* [PATCH v2 2/6] header file for DRBG
2014-03-17 7:34 ` [PATCH v2 " Stephan Mueller
@ 2014-03-17 7:35 ` Stephan Mueller
2014-03-17 7:35 ` [PATCH v2 3/6] DRBG kernel configuration options Stephan Mueller
2014-04-11 18:07 ` [PATCH v4 2/6] header file for DRBG Stephan Mueller
2014-03-19 7:51 ` [PATCH v2 1/6] SP800-90A Deterministic Random Bit Generator Stephan Mueller
` (3 subsequent siblings)
4 siblings, 2 replies; 29+ messages in thread
From: Stephan Mueller @ 2014-03-17 7:35 UTC (permalink / raw)
To: linux-kernel, linux-crypto; +Cc: aquini, jeremy.wayne.powell
The header file includes the definition of:
* DRBG data structures with
- struct drbg_state as main structure
- struct drbg_core referencing the backend ciphers
- struct drbg_state_ops callbach handlers for specific code
supporting the Hash, HMAC, CTR DRBG implementations
- struct drbg_string defining a linked list for input data
- struct drbg_test_data holding the test "entropy" data for CAVS
testing and testmgr.c
- struct drbg_gen allowing test data, additional information
string and personalization string data to be funneled through
the kernel crypto API -- the DRBG requires additional
parameters when invoking the reset and random number
generation requests than intended by the kernel crypto API
* wrapper function to the kernel crypto API functions using struct
drbg_gen to pass through all data needed for DRBG
* wrapper functions to kernel crypto API functions usable for testing
code to inject test_data into the DRBG as needed by CAVS testing and
testmgr.c.
* DRBG flags required for the operation of the DRBG and for selecting
the particular DRBG type and backend cipher
* getter functions for data from struct drbg_core
Changes to v1:
* Changes due to modification of drbg.c as documented in PATCH 1
* Fix coding style and apply scripts/checkpatch.pl
Signed-off-by: Stephan Mueller <smueller@chronox.de>
---
create mode 100644 include/crypto/drbg.h
diff --git a/include/crypto/drbg.h b/include/crypto/drbg.h
new file mode 100644
index 0000000..f52e7ca
--- /dev/null
+++ b/include/crypto/drbg.h
@@ -0,0 +1,292 @@
+/*
+ * DRBG based on NIST SP800-90A
+ *
+ * Copyright Stephan Mueller <smueller@chronox.de>, 2014
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, and the entire permission notice in its entirety,
+ * including the disclaimer of warranties.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote
+ * products derived from this software without specific prior
+ * written permission.
+ *
+ * ALTERNATIVELY, this product may be distributed under the terms of
+ * the GNU General Public License, in which case the provisions of the GPL are
+ * required INSTEAD OF the above restrictions. (This clause is
+ * necessary due to a potential bad interaction between the GPL and
+ * the restrictions contained in a BSD-style copyright.)
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF
+ * WHICH ARE HEREBY DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+ * USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ */
+
+#ifndef _DRBG_H
+#define _DRBG_H
+
+
+#include <linux/random.h>
+#include <linux/scatterlist.h>
+#include <crypto/hash.h>
+#include <linux/module.h>
+#include <linux/crypto.h>
+#include <linux/slab.h> /* needed for kzalloc */
+#include <crypto/internal/rng.h>
+#include <crypto/rng.h>
+#include <linux/fips.h>
+#include <linux/spinlock.h>
+
+/*
+ * Concatenation Helper and string operation helper
+ *
+ * SP800-90A requires the concatenation of different data. To avoid copying
+ * buffers around or allocate additional memory, the following data structure
+ * is used to point to the original memory with its size. In addition, it
+ * is used to build a linked list. The linked list defines the concatenation
+ * of individual buffers. The order of memory block referenced in that
+ * linked list determines the order of concatenation.
+ */
+
+struct drbg_string {
+ const unsigned char *buf;
+ size_t len;
+ struct drbg_string *next;
+};
+
+static inline void drbg_string_fill(struct drbg_string *string,
+ const unsigned char *buf, size_t len)
+{
+ string->buf = buf;
+ string->len = len;
+ string->next = NULL;
+}
+
+struct drbg_state;
+typedef uint32_t drbg_flag_t;
+
+struct drbg_core {
+ drbg_flag_t flags; /* flags for the cipher */
+ __u8 statelen; /* maximum state length */
+ __u8 max_addtllen; /* maximum length of personalization string or
+ additional input string -- exponent for base
+ 2 */
+ __u8 max_bits; /* maximum bits per RNG request -- exponent for
+ base 2*/
+ __u8 max_req; /* maximum number of requests -- exponent for
+ base 2 */
+ __u8 blocklen_bytes; /* block size of output in bytes */
+ char cra_name[CRYPTO_MAX_ALG_NAME]; /* mapping to kernel crypto API */
+ char cra_driver_name[CRYPTO_MAX_ALG_NAME]; /* mapping to kernel crypto
+ * API */
+ char backend_cra_name[CRYPTO_MAX_ALG_NAME]; /* kernel crypto API
+ * backend cipher name */
+};
+
+struct drbg_state_ops {
+ int (*update)(struct drbg_state *drbg, struct drbg_string *seed,
+ int reseed);
+ unsigned int (*generate)(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl);
+ int (*crypto_init)(struct drbg_state *drbg);
+ int (*crypto_fini)(struct drbg_state *drbg);
+
+};
+
+struct drbg_test_data {
+ struct drbg_string *testentropy; /* TEST PARAMETER: test entropy */
+};
+
+struct drbg_state {
+ spinlock_t drbg_lock; /* lock around DRBG */
+ unsigned char *V; /* internal state 10.1.1.1 1a) */
+ unsigned char *C; /* hash: static value 10.1.1.1 1b)
+ * hmac / ctr: key */
+ size_t reseed_ctr; /* Number of RNG requests since last reseed --
+ * 10.1.1.1 1c) */
+ unsigned char *scratchpad; /* some memory the DRBG can use for its
+ * operation -- allocated during init */
+ void *priv_data; /* Data needed for specific cipher
+ * implementation */
+ bool seeded; /* DRBG fully seeded? */
+ bool pr; /* Prediction resistance enabled? */
+#ifdef CONFIG_CRYPTO_FIPS
+ bool fips_primed; /* Continuous test primed? */
+ unsigned char *prev; /* previous output value of DRBG_BLOCKLEN for
+ * FIPS 140-2 continuous test */
+#endif
+ const struct drbg_state_ops *d_ops;
+ const struct drbg_core *core;
+ struct drbg_test_data *test_data;
+};
+
+/* helper functions */
+static inline __u8 drbg_statelen(struct drbg_state *drbg)
+{
+ if (drbg && drbg->core)
+ return drbg->core->statelen;
+ return 0;
+}
+
+static inline __u8 drbg_blocklen(struct drbg_state *drbg)
+{
+ if (drbg && drbg->core)
+ return drbg->core->blocklen_bytes;
+ return 0;
+}
+
+static inline __u8 drbg_keylen(struct drbg_state *drbg)
+{
+ if (drbg && drbg->core)
+ return (drbg->core->statelen - drbg->core->blocklen_bytes);
+ return 0;
+}
+
+static inline size_t drbg_max_request_bytes(struct drbg_state *drbg)
+{
+ /* max_bits is in bits, but buflen is in bytes */
+ return (1 << (drbg->core->max_bits - 3));
+}
+
+static inline size_t drbg_max_addtl(struct drbg_state *drbg)
+{
+ return (1UL<<(drbg->core->max_addtllen));
+}
+
+static inline size_t drbg_max_requests(struct drbg_state *drbg)
+{
+ return (1UL<<(drbg->core->max_req));
+}
+
+/* kernel crypto API input data structure for DRBG generate in case dlen
+ * is set to 0 */
+struct drbg_gen {
+ unsigned char *outbuf; /* output buffer for random numbers */
+ unsigned int outlen; /* size of output buffer */
+ struct drbg_string *addtl; /* input buffer for
+ * additional information string */
+ struct drbg_test_data *test_data; /* test data */
+};
+
+/*
+ * This is a wrapper to the kernel crypto API function of
+ * crypto_rng_get_bytes() to allow the caller to provide additional data
+ *
+ * @drng DRBG handle -- see crypto_rng_get_bytes
+ * @outbuf output buffer -- see crypto_rng_get_bytes
+ * @outlen length of output buffer -- see crypto_rng_get_bytes
+ * @addtl_input additional information string input buffer
+ * @addtllen length of additional information string buffer
+ *
+ * return
+ * see crypto_rng_get_bytes
+ */
+static inline int crypto_drbg_get_bytes_addtl(struct crypto_rng *drng,
+ unsigned char *outbuf, unsigned int outlen,
+ struct drbg_string *addtl)
+{
+ int ret;
+ struct drbg_gen genbuf;
+ genbuf.outbuf = outbuf;
+ genbuf.outlen = outlen;
+ genbuf.addtl = addtl;
+ genbuf.test_data = NULL;
+ ret = crypto_rng_get_bytes(drng, (u8 *)&genbuf, 0);
+ return ret;
+}
+
+/*
+ * TEST code
+ *
+ * This is a wrapper to the kernel crypto API function of
+ * crypto_rng_get_bytes() to allow the caller to provide additional data and
+ * allow furnishing of test_data
+ *
+ * @drng DRBG handle -- see crypto_rng_get_bytes
+ * @outbuf output buffer -- see crypto_rng_get_bytes
+ * @outlen length of output buffer -- see crypto_rng_get_bytes
+ * @addtl_input additional information string input buffer
+ * @addtllen length of additional information string buffer
+ * @test_data filled test data
+ *
+ * return
+ * see crypto_rng_get_bytes
+ */
+static inline int crypto_drbg_get_bytes_addtl_test(struct crypto_rng *drng,
+ unsigned char *outbuf, unsigned int outlen,
+ struct drbg_string *addtl,
+ struct drbg_test_data *test_data)
+{
+ int ret;
+ struct drbg_gen genbuf;
+ genbuf.outbuf = outbuf;
+ genbuf.outlen = outlen;
+ genbuf.addtl = addtl;
+ genbuf.test_data = test_data;
+ ret = crypto_rng_get_bytes(drng, (u8 *)&genbuf, 0);
+ return ret;
+}
+
+/*
+ * TEST code
+ *
+ * This is a wrapper to the kernel crypto API function of
+ * crypto_rng_reset() to allow the caller to provide test_data
+ *
+ * @drng DRBG handle -- see crypto_rng_reset
+ * @pers personalization string input buffer
+ * @perslen length of additional information string buffer
+ * @test_data filled test data
+ *
+ * return
+ * see crypto_rng_reset
+ */
+static inline int crypto_drbg_reset_test(struct crypto_rng *drng,
+ struct drbg_string *pers,
+ struct drbg_test_data *test_data)
+{
+ int ret;
+ struct drbg_gen genbuf;
+ genbuf.outbuf = NULL;
+ genbuf.outlen = 0;
+ genbuf.addtl = pers;
+ genbuf.test_data = test_data;
+ ret = crypto_rng_reset(drng, (u8 *)&genbuf, 0);
+ return ret;
+}
+
+/* DRBG type flags */
+#define DRBG_CTR ((drbg_flag_t)1<<0)
+#define DRBG_HMAC ((drbg_flag_t)1<<1)
+#define DRBG_HASH ((drbg_flag_t)1<<2)
+#define DRBG_TYPE_MASK (DRBG_CTR | DRBG_HMAC | DRBG_HASH)
+/* DRBG strength flags */
+#define DRBG_STRENGTH128 ((drbg_flag_t)1<<3)
+#define DRBG_STRENGTH192 ((drbg_flag_t)1<<4)
+#define DRBG_STRENGTH256 ((drbg_flag_t)1<<5)
+#define DRBG_STRENGTH_MASK (DRBG_STRENGTH128 | DRBG_STRENGTH192 | \
+ DRBG_STRENGTH256)
+
+enum drbg_prefixes {
+ DRBG_PREFIX0 = 0x00,
+ DRBG_PREFIX1,
+ DRBG_PREFIX2,
+ DRBG_PREFIX3
+};
+
+#endif /* _DRBG_H */
^ permalink raw reply related [flat|nested] 29+ messages in thread* [PATCH v2 3/6] DRBG kernel configuration options
2014-03-17 7:35 ` [PATCH v2 2/6] header file for DRBG Stephan Mueller
@ 2014-03-17 7:35 ` Stephan Mueller
2014-03-17 7:37 ` [PATCH v2 4/6] compile the DRBG code Stephan Mueller
2014-04-11 18:07 ` [PATCH v4 2/6] header file for DRBG Stephan Mueller
1 sibling, 1 reply; 29+ messages in thread
From: Stephan Mueller @ 2014-03-17 7:35 UTC (permalink / raw)
To: linux-kernel, linux-crypto; +Cc: aquini, jeremy.wayne.powell
The different DRBG types of CTR, Hash, HMAC can be enabled or disabled
at compile time. At least one DRBG type shall be selected.
The default is the HMAC DRBG as its code base is smallest.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
---
diff --git a/crypto/Kconfig b/crypto/Kconfig
index 7bcb70d..2cdf9c6 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -23,7 +23,7 @@ comment "Crypto core or helper"
config CRYPTO_FIPS
bool "FIPS 200 compliance"
- depends on CRYPTO_ANSI_CPRNG && !CRYPTO_MANAGER_DISABLE_TESTS
+ depends on (CRYPTO_ANSI_CPRNG || CRYTPO_DRBG) && !CRYPTO_MANAGER_DISABLE_TESTS
help
This options enables the fips boot option which is
required if you want to system to operate in a FIPS 200
@@ -1380,6 +1380,40 @@ config CRYPTO_ANSI_CPRNG
ANSI X9.31 A.2.4. Note that this option must be enabled if
CRYPTO_FIPS is selected
+menuconfig CRYTPO_DRBG
+ tristate "NIST SP800-90A DRBG"
+ depends on CRYPTO
+ select CRYPTO_RNG
+ help
+ NIST SP800-90A compliant DRBG. In the following submenu, one or
+ more of the DRBG types must be selected.
+
+if CRYTPO_DRBG
+
+config CRYPTO_DRBG_HMAC
+ bool "Enable HMAC DRBG"
+ default y
+ depends on CRYTPO_DRBG
+ select CRYPTO_HMAC
+ help
+ Enable the HMAC DRBG variant as defined in NIST SP800-90A.
+
+config CRYPTO_DRBG_HASH
+ bool "Enable Hash DRBG"
+ depends on CRYTPO_DRBG
+ select CRYPTO_HASH
+ help
+ Enable the Hash DRBG variant as defined in NIST SP800-90A.
+
+config CRYPTO_DRBG_CTR
+ bool "Enable CTR DRBG"
+ depends on CRYTPO_DRBG
+ select CRYPTO_AES
+ help
+ Enable the CTR DRBG variant as defined in NIST SP800-90A.
+
+endif #CRYTPO_DRBG
+
config CRYPTO_USER_API
tristate
--
1.8.5.3
^ permalink raw reply related [flat|nested] 29+ messages in thread
* [PATCH v2 4/6] compile the DRBG code
2014-03-17 7:35 ` [PATCH v2 3/6] DRBG kernel configuration options Stephan Mueller
@ 2014-03-17 7:37 ` Stephan Mueller
2014-03-17 7:38 ` [PATCH v2 5/6] DRBG testmgr test vectors Stephan Mueller
0 siblings, 1 reply; 29+ messages in thread
From: Stephan Mueller @ 2014-03-17 7:37 UTC (permalink / raw)
To: linux-kernel, linux-crypto; +Cc: aquini, jeremy.wayne.powell
Signed-off-by: Stephan Mueller <smueller@chronox.de>
---
diff --git a/crypto/Makefile b/crypto/Makefile
index b29402a..0d63373 100644
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -92,6 +92,7 @@ obj-$(CONFIG_CRYPTO_842) += 842.o
obj-$(CONFIG_CRYPTO_RNG2) += rng.o
obj-$(CONFIG_CRYPTO_RNG2) += krng.o
obj-$(CONFIG_CRYPTO_ANSI_CPRNG) += ansi_cprng.o
+obj-$(CONFIG_CRYTPO_DRBG) += drbg.o
obj-$(CONFIG_CRYPTO_TEST) += tcrypt.o
obj-$(CONFIG_CRYPTO_GHASH) += ghash-generic.o
obj-$(CONFIG_CRYPTO_USER_API) += af_alg.o
--
1.8.5.3
^ permalink raw reply related [flat|nested] 29+ messages in thread
* [PATCH v2 5/6] DRBG testmgr test vectors
2014-03-17 7:37 ` [PATCH v2 4/6] compile the DRBG code Stephan Mueller
@ 2014-03-17 7:38 ` Stephan Mueller
2014-03-17 7:39 ` [PATCH v2 6/6] Add DRBG test code to testmgr Stephan Mueller
0 siblings, 1 reply; 29+ messages in thread
From: Stephan Mueller @ 2014-03-17 7:38 UTC (permalink / raw)
To: linux-kernel, linux-crypto; +Cc: aquini, jeremy.wayne.powell
All types of the DRBG (CTR, HMAC, Hash) are covered with test vectors.
In addition, all permutations of use cases of the DRBG are covered:
* with and without predition resistance
* with and without additional information string
* with and without personalization string
As the DRBG implementation is agnositc of the specific backend cipher,
only test vectors for one specific backend cipher is used. For example:
the Hash DRBG uses the same code paths irrespectively of using SHA-256
or SHA-512. Thus, the test vectors for SHA-256 cover the testing of all
DRBG code paths of SHA-512.
Changes to v1:
* Fix coding style and apply scripts/checkpatch.pl
Signed-off-by: Stephan Mueller <smueller@chronox.de>
---
diff --git a/crypto/testmgr.h b/crypto/testmgr.h
index 7d44aa3..1f48312 100644
--- a/crypto/testmgr.h
+++ b/crypto/testmgr.h
@@ -92,6 +92,29 @@ struct cprng_testvec {
unsigned short loops;
};
+struct drbg_testvec {
+ unsigned char *entropy; /* entropy string for initialization -- this
+ * string is a concatenation of the entropy
+ * and nonce variable from CAVS */
+ size_t entropylen; /* length of entropy and nonce variable */
+ unsigned char *entpra; /* for prediction resistance: entropy for
+ * first reseeding */
+ unsigned char *entprb; /* for prediction resistance: entropy for
+ * second reseeding */
+ size_t entprlen; /* length of prediction resistance entropy */
+ unsigned char *addtla; /* additional input string for first random
+ * value */
+ unsigned char *addtlb; /* additional input string for second random
+ * value */
+ size_t addtllen; /* length of additional input string */
+ unsigned char *pers; /* personalization string */
+ size_t perslen; /* personalization string length */
+ unsigned char *expected; /* expected random value -- for CAVS test,
+ this value does not apply and the memcmp
+ in drbg_cavs_test does not apply either*/
+ size_t expectedlen; /* length of expected random value */
+};
+
static char zeroed_string[48];
/*
@@ -19162,6 +19185,834 @@ static struct cprng_testvec ansi_cprng_aes_tv_template[] = {
},
};
+/*
+ * SP800-90A DRBG Test vectors from
+ * http://csrc.nist.gov/groups/STM/cavp/documents/drbg/drbgtestvectors.zip
+ *
+ * Test vectors for DRBG with prediction resistance. All types of DRBGs
+ * (Hash, HMAC, CTR) are tested with all permutations of use cases (w/ and
+ * w/o personalization string, w/ and w/o additional input string).
+ */
+static struct drbg_testvec drbg_pr_sha256_tv_template[] = {
+ {
+ .entropy = (unsigned char *)
+ "\x72\x88\x4c\xcd\x6c\x85\x57\x70\xf7\x0b\x8b\x86"
+ "\xc1\xeb\xd2\x4e\x36\x14\xab\x18\xc4\x9c\xc9\xcf"
+ "\x1a\xe8\xf7\x7b\x02\x49\x73\xd7\xf1\x42\x7d\xc6"
+ "\x3f\x29\x2d\xec\xd3\x66\x51\x3f\x1d\x8d\x5b\x4e",
+ .entropylen = 48,
+ .entpra = (unsigned char *)
+ "\x38\x9c\x91\xfa\xc2\xa3\x46\x89\x56\x08\x3f\x62"
+ "\x73\xd5\x22\xa9\x29\x63\x3a\x1d\xe5\x5d\x5e\x4f"
+ "\x67\xb0\x67\x7a\x5e\x9e\x0c\x62",
+ .entprb = (unsigned char *)
+ "\xb2\x8f\x36\xb2\xf6\x8d\x39\x13\xfa\x6c\x66\xcf"
+ "\x62\x8a\x7e\x8c\x12\x33\x71\x9c\x69\xe4\xa5\xf0"
+ "\x8c\xee\xeb\x9c\xf5\x31\x98\x31",
+ .entprlen = 32,
+ .expected = (unsigned char *)
+ "\x52\x7b\xa3\xad\x71\x77\xa4\x49\x42\x04\x61\xc7"
+ "\xf0\xaf\xa5\xfd\xd3\xb3\x0d\x6a\x61\xba\x35\x49"
+ "\xbb\xaa\xaf\xe4\x25\x7d\xb5\x48\xaf\x5c\x18\x3d"
+ "\x33\x8d\x9d\x45\xdf\x98\xd5\x94\xa8\xda\x92\xfe"
+ "\xc4\x3c\x94\x2a\xcf\x7f\x7b\xf2\xeb\x28\xa9\xf1"
+ "\xe0\x86\x30\xa8\xfe\xf2\x48\x90\x91\x0c\x75\xb5"
+ "\x3c\x00\xf0\x4d\x09\x4f\x40\xa7\xa2\x8c\x52\xdf"
+ "\x52\xef\x17\xbf\x3d\xd1\xa2\x31\xb4\xb8\xdc\xe6"
+ "\x5b\x0d\x1f\x78\x36\xb4\xe6\x4b\xa7\x11\x25\xd5"
+ "\x94\xc6\x97\x36\xab\xf0\xe5\x31\x28\x6a\xbb\xce"
+ "\x30\x81\xa6\x8f\x27\x14\xf8\x1c",
+ .expectedlen = 128,
+ .addtla = NULL,
+ .addtlb = NULL,
+ .addtllen = 0,
+ .pers = NULL,
+ .perslen = 0,
+ }, {
+ .entropy = (unsigned char *)
+ "\x5d\xf2\x14\xbc\xf6\xb5\x4e\x0b\xf0\x0d\x6f\x2d"
+ "\xe2\x01\x66\x7b\xd0\xa4\x73\xa4\x21\xdd\xb0\xc0"
+ "\x51\x79\x09\xf4\xea\xa9\x08\xfa\xa6\x67\xe0\xe1"
+ "\xd1\x88\xa8\xad\xee\x69\x74\xb3\x55\x06\x9b\xf6",
+ .entropylen = 48,
+ .entpra = (unsigned char *)
+ "\xef\x48\x06\xa2\xc2\x45\xf1\x44\xfa\x34\x2c\xeb"
+ "\x8d\x78\x3c\x09\x8f\x34\x72\x20\xf2\xe7\xfd\x13"
+ "\x76\x0a\xf6\xdc\x3c\xf5\xc0\x15",
+ .entprb = (unsigned char *)
+ "\x4b\xbe\xe5\x24\xed\x6a\x2d\x0c\xdb\x73\x5e\x09"
+ "\xf9\xad\x67\x7c\x51\x47\x8b\x6b\x30\x2a\xc6\xde"
+ "\x76\xaa\x55\x04\x8b\x0a\x72\x95",
+ .entprlen = 32,
+ .expected = (unsigned char *)
+ "\x3b\x14\x71\x99\xa1\xda\xa0\x42\xe6\xc8\x85\x32"
+ "\x70\x20\x32\x53\x9a\xbe\xd1\x1e\x15\xef\xfb\x4c"
+ "\x25\x6e\x19\x3a\xf0\xb9\xcb\xde\xf0\x3b\xc6\x18"
+ "\x4d\x85\x5a\x9b\xf1\xe3\xc2\x23\x03\x93\x08\xdb"
+ "\xa7\x07\x4b\x33\x78\x40\x4d\xeb\x24\xf5\x6e\x81"
+ "\x4a\x1b\x6e\xa3\x94\x52\x43\xb0\xaf\x2e\x21\xf4"
+ "\x42\x46\x8e\x90\xed\x34\x21\x75\xea\xda\x67\xb6"
+ "\xe4\xf6\xff\xc6\x31\x6c\x9a\x5a\xdb\xb3\x97\x13"
+ "\x09\xd3\x20\x98\x33\x2d\x6d\xd7\xb5\x6a\xa8\xa9"
+ "\x9a\x5b\xd6\x87\x52\xa1\x89\x2b\x4b\x9c\x64\x60"
+ "\x50\x47\xa3\x63\x81\x16\xaf\x19",
+ .expectedlen = 128,
+ .addtla = (unsigned char *)
+ "\xbe\x13\xdb\x2a\xe9\xa8\xfe\x09\x97\xe1\xce\x5d"
+ "\xe8\xbb\xc0\x7c\x4f\xcb\x62\x19\x3f\x0f\xd2\xad"
+ "\xa9\xd0\x1d\x59\x02\xc4\xff\x70",
+ .addtlb = (unsigned char *)
+ "\x6f\x96\x13\xe2\xa7\xf5\x6c\xfe\xdf\x66\xe3\x31"
+ "\x63\x76\xbf\x20\x27\x06\x49\xf1\xf3\x01\x77\x41"
+ "\x9f\xeb\xe4\x38\xfe\x67\x00\xcd",
+ .addtllen = 32,
+ .pers = NULL,
+ .perslen = 0,
+ }, {
+ .entropy = (unsigned char *)
+ "\xc6\x1c\xaf\x83\xa2\x56\x38\xf9\xb0\xbc\xd9\x85"
+ "\xf5\x2e\xc4\x46\x9c\xe1\xb9\x40\x98\x70\x10\x72"
+ "\xd7\x7d\x15\x85\xa1\x83\x5a\x97\xdf\xc8\xa8\xe8"
+ "\x03\x4c\xcb\x70\x35\x8b\x90\x94\x46\x8a\x6e\xa1",
+ .entropylen = 48,
+ .entpra = (unsigned char *)
+ "\xc9\x05\xa4\xcf\x28\x80\x4b\x93\x0f\x8b\xc6\xf9"
+ "\x09\x41\x58\x74\xe9\xec\x28\xc7\x53\x0a\x73\x60"
+ "\xba\x0a\xde\x57\x5b\x4b\x9f\x29",
+ .entprb = (unsigned char *)
+ "\x4f\x31\xd2\xeb\xac\xfa\xa8\xe2\x01\x7d\xf3\xbd"
+ "\x42\xbd\x20\xa0\x30\x65\x74\xd5\x5d\xd2\xad\xa4"
+ "\xa9\xeb\x1f\x4d\xf6\xfd\xb8\x26",
+ .entprlen = 32,
+ .expected = (unsigned char *)
+ "\xf6\x13\x05\xcb\x83\x60\x16\x42\x49\x1d\xc6\x25"
+ "\x3b\x8c\x31\xa3\xbe\x8b\xbd\x1c\xe2\xec\x1d\xde"
+ "\xbb\xbf\xa1\xac\xa8\x9f\x50\xce\x69\xce\xef\xd5"
+ "\xd6\xf2\xef\x6a\xf7\x81\x38\xdf\xbc\xa7\x5a\xb9"
+ "\xb2\x42\x65\xab\xe4\x86\x8d\x2d\x9d\x59\x99\x2c"
+ "\x5a\x0d\x71\x55\x98\xa4\x45\xc2\x8d\xdb\x05\x5e"
+ "\x50\x21\xf7\xcd\xe8\x98\x43\xce\x57\x74\x63\x4c"
+ "\xf3\xb1\xa5\x14\x1e\x9e\x01\xeb\x54\xd9\x56\xae"
+ "\xbd\xb6\x6f\x1a\x47\x6b\x3b\x44\xe4\xa2\xe9\x3c"
+ "\x6c\x83\x12\x30\xb8\x78\x7f\x8e\x54\x82\xd4\xfe"
+ "\x90\x35\x0d\x4c\x4d\x85\xe7\x13",
+ .expectedlen = 128,
+ .addtla = NULL,
+ .addtlb = NULL,
+ .addtllen = 0,
+ .pers = (unsigned char *)
+ "\xa5\xbf\xac\x4f\x71\xa1\xbb\x67\x94\xc6\x50\xc7"
+ "\x2a\x45\x9e\x10\xa8\xed\xf7\x52\x4f\xfe\x21\x90"
+ "\xa4\x1b\xe1\xe2\x53\xcc\x61\x47",
+ .perslen = 32,
+ }, {
+ .entropy = (unsigned char *)
+ "\xb6\xc1\x8d\xdf\x99\x54\xbe\x95\x10\x48\xd9\xf6"
+ "\xd7\x48\xa8\x73\x2d\x74\xde\x1e\xde\x57\x7e\xf4"
+ "\x7b\x7b\x64\xef\x88\x7a\xa8\x10\x4b\xe1\xc1\x87"
+ "\xbb\x0b\xe1\x39\x39\x50\xaf\x68\x9c\xa2\xbf\x5e",
+ .entropylen = 48,
+ .entpra = (unsigned char *)
+ "\xdc\x81\x0a\x01\x58\xa7\x2e\xce\xee\x48\x8c\x7c"
+ "\x77\x9e\x3c\xf1\x17\x24\x7a\xbb\xab\x9f\xca\x12"
+ "\x19\xaf\x97\x2d\x5f\xf9\xff\xfc",
+ .entprb = (unsigned char *)
+ "\xaf\xfc\x4f\x98\x8b\x93\x95\xc1\xb5\x8b\x7f\x73"
+ "\x6d\xa6\xbe\x6d\x33\xeb\x2c\x82\xb1\xaf\xc1\xb6"
+ "\xb6\x05\xe2\x44\xaa\xfd\xe7\xdb",
+ .entprlen = 32,
+ .expected = (unsigned char *)
+ "\x51\x79\xde\x1c\x0f\x58\xf3\xf4\xc9\x57\x2e\x31"
+ "\xa7\x09\xa1\x53\x64\x63\xa2\xc5\x1d\x84\x88\x65"
+ "\x01\x1b\xc6\x16\x3c\x49\x5b\x42\x8e\x53\xf5\x18"
+ "\xad\x94\x12\x0d\x4f\x55\xcc\x45\x5c\x98\x0f\x42"
+ "\x28\x2f\x47\x11\xf9\xc4\x01\x97\x6b\xa0\x94\x50"
+ "\xa9\xd1\x5e\x06\x54\x3f\xdf\xbb\xc4\x98\xee\x8b"
+ "\xba\xa9\xfa\x49\xee\x1d\xdc\xfb\x50\xf6\x51\x9f"
+ "\x6c\x4a\x9a\x6f\x63\xa2\x7d\xad\xaf\x3a\x24\xa0"
+ "\xd9\x9f\x07\xeb\x15\xee\x26\xe0\xd5\x63\x39\xda"
+ "\x3c\x59\xd6\x33\x6c\x02\xe8\x05\x71\x46\x68\x44"
+ "\x63\x4a\x68\x72\xe9\xf5\x55\xfe",
+ .expectedlen = 128,
+ .addtla = (unsigned char *)
+ "\x15\x20\x2f\xf6\x98\x28\x63\xa2\xc4\x4e\xbb\x6c"
+ "\xb2\x25\x92\x61\x79\xc9\x22\xc4\x61\x54\x96\xff"
+ "\x4a\x85\xca\x80\xfe\x0d\x1c\xd0",
+ .addtlb = (unsigned char *)
+ "\xde\x29\x8e\x03\x42\x61\xa3\x28\x5e\xc8\x80\xc2"
+ "\x6d\xbf\xad\x13\xe1\x8d\x2a\xc7\xe8\xc7\x18\x89"
+ "\x42\x58\x9e\xd6\xcc\xad\x7b\x1e",
+ .addtllen = 32,
+ .pers = (unsigned char *)
+ "\x84\xc3\x73\x9e\xce\xb3\xbc\x89\xf7\x62\xb3\xe1"
+ "\xd7\x48\x45\x8a\xa9\xcc\xe9\xed\xd5\x81\x84\x52"
+ "\x82\x4c\xdc\x19\xb8\xf8\x92\x5c",
+ .perslen = 32,
+ },
+};
+
+static struct drbg_testvec drbg_pr_hmac_sha256_tv_template[] = {
+ {
+ .entropy = (unsigned char *)
+ "\x99\x69\xe5\x4b\x47\x03\xff\x31\x78\x5b\x87\x9a"
+ "\x7e\x5c\x0e\xae\x0d\x3e\x30\x95\x59\xe9\xfe\x96"
+ "\xb0\x67\x6d\x49\xd5\x91\xea\x4d\x07\xd2\x0d\x46"
+ "\xd0\x64\x75\x7d\x30\x23\xca\xc2\x37\x61\x27\xab",
+ .entropylen = 48,
+ .entpra = (unsigned char *)
+ "\xc6\x0f\x29\x99\x10\x0f\x73\x8c\x10\xf7\x47\x92"
+ "\x67\x6a\x3f\xc4\xa2\x62\xd1\x37\x21\x79\x80\x46"
+ "\xe2\x9a\x29\x51\x81\x56\x9f\x54",
+ .entprb = (unsigned char *)
+ "\xc1\x1d\x45\x24\xc9\x07\x1b\xd3\x09\x60\x15\xfc"
+ "\xf7\xbc\x24\xa6\x07\xf2\x2f\xa0\x65\xc9\x37\x65"
+ "\x8a\x2a\x77\xa8\x69\x90\x89\xf4",
+ .entprlen = 32,
+ .expected = (unsigned char *)
+ "\xab\xc0\x15\x85\x60\x94\x80\x3a\x93\x8d\xff\xd2"
+ "\x0d\xa9\x48\x43\x87\x0e\xf9\x35\xb8\x2c\xfe\xc1"
+ "\x77\x06\xb8\xf5\x51\xb8\x38\x50\x44\x23\x5d\xd4"
+ "\x4b\x59\x9f\x94\xb3\x9b\xe7\x8d\xd4\x76\xe0\xcf"
+ "\x11\x30\x9c\x99\x5a\x73\x34\xe0\xa7\x8b\x37\xbc"
+ "\x95\x86\x23\x50\x86\xfa\x3b\x63\x7b\xa9\x1c\xf8"
+ "\xfb\x65\xef\xa2\x2a\x58\x9c\x13\x75\x31\xaa\x7b"
+ "\x2d\x4e\x26\x07\xaa\xc2\x72\x92\xb0\x1c\x69\x8e"
+ "\x6e\x01\xae\x67\x9e\xb8\x7c\x01\xa8\x9c\x74\x22"
+ "\xd4\x37\x2d\x6d\x75\x4a\xba\xbb\x4b\xf8\x96\xfc"
+ "\xb1\xcd\x09\xd6\x92\xd0\x28\x3f",
+ .expectedlen = 128,
+ .addtla = NULL,
+ .addtlb = NULL,
+ .addtllen = 0,
+ .pers = NULL,
+ .perslen = 0,
+ }, {
+ .entropy = (unsigned char *)
+ "\xb9\x1f\xe9\xef\xdd\x9b\x7d\x20\xb6\xec\xe0\x2f"
+ "\xdb\x76\x24\xce\x41\xc8\x3a\x4a\x12\x7f\x3e\x2f"
+ "\xae\x05\x99\xea\xb5\x06\x71\x0d\x0c\x4c\xb4\x05"
+ "\x26\xc6\xbd\xf5\x7f\x2a\x3d\xf2\xb5\x49\x7b\xda",
+ .entropylen = 48,
+ .entpra = (unsigned char *)
+ "\xef\x67\x50\x9c\xa7\x7d\xdf\xb7\x2d\x81\x01\xa4"
+ "\x62\x81\x6a\x69\x5b\xb3\x37\x45\xa7\x34\x8e\x26"
+ "\x46\xd9\x26\xa2\x19\xd4\x94\x43",
+ .entprb = (unsigned char *)
+ "\x97\x75\x53\x53\xba\xb4\xa6\xb2\x91\x60\x71\x79"
+ "\xd1\x6b\x4a\x24\x9a\x34\x66\xcc\x33\xab\x07\x98"
+ "\x51\x78\x72\xb2\x79\xfd\x2c\xff",
+ .entprlen = 32,
+ .expected = (unsigned char *)
+ "\x9c\xdc\x63\x8a\x19\x23\x22\x66\x0c\xc5\xb9\xd7"
+ "\xfb\x2a\xb0\x31\xe3\x8a\x36\xa8\x5a\xa8\x14\xda"
+ "\x1e\xa9\xcc\xfe\xb8\x26\x44\x83\x9f\xf6\xff\xaa"
+ "\xc8\x98\xb8\x30\x35\x3b\x3d\x36\xd2\x49\xd4\x40"
+ "\x62\x0a\x65\x10\x76\x55\xef\xc0\x95\x9c\xa7\xda"
+ "\x3f\xcf\xb7\x7b\xc6\xe1\x28\x52\xfc\x0c\xe2\x37"
+ "\x0d\x83\xa7\x51\x4b\x31\x47\x3c\xe1\x3c\xae\x70"
+ "\x01\xc8\xa3\xd3\xc2\xac\x77\x9c\xd1\x68\x77\x9b"
+ "\x58\x27\x3b\xa5\x0f\xc2\x7a\x8b\x04\x65\x62\xd5"
+ "\xe8\xd6\xfe\x2a\xaf\xd3\xd3\xfe\xbd\x18\xfb\xcd"
+ "\xcd\x66\xb5\x01\x69\x66\xa0\x3c",
+ .expectedlen = 128,
+ .addtla = (unsigned char *)
+ "\x17\xc1\x56\xcb\xcc\x50\xd6\x03\x7d\x45\x76\xa3"
+ "\x75\x76\xc1\x4a\x66\x1b\x2e\xdf\xb0\x2e\x7d\x56"
+ "\x6d\x99\x3b\xc6\x58\xda\x03\xf6",
+ .addtlb = (unsigned char *)
+ "\x7c\x7b\x4a\x4b\x32\x5e\x6f\x67\x34\xf5\x21\x4c"
+ "\xf9\x96\xf9\xbf\x1c\x8c\x81\xd3\x9b\x60\x6a\x44"
+ "\xc6\x03\xa2\xfb\x13\x20\x19\xb7",
+ .addtllen = 32,
+ .pers = NULL,
+ .perslen = 0,
+ }, {
+ .entropy = (unsigned char *)
+ "\x13\x54\x96\xfc\x1b\x7d\x28\xf3\x18\xc9\xa7\x89"
+ "\xb6\xb3\xc8\x72\xac\x00\xd4\x59\x36\x25\x05\xaf"
+ "\xa5\xdb\x96\xcb\x3c\x58\x46\x87\xa5\xaa\xbf\x20"
+ "\x3b\xfe\x23\x0e\xd1\xc7\x41\x0f\x3f\xc9\xb3\x67",
+ .entropylen = 48,
+ .entpra = (unsigned char *)
+ "\xe2\xbd\xb7\x48\x08\x06\xf3\xe1\x93\x3c\xac\x79"
+ "\xa7\x2b\x11\xda\xe3\x2e\xe1\x91\xa5\x02\x19\x57"
+ "\x20\x28\xad\xf2\x60\xd7\xcd\x45",
+ .entprb = (unsigned char *)
+ "\x8b\xd4\x69\xfc\xff\x59\x95\x95\xc6\x51\xde\x71"
+ "\x68\x5f\xfc\xf9\x4a\xab\xec\x5a\xcb\xbe\xd3\x66"
+ "\x1f\xfa\x74\xd3\xac\xa6\x74\x60",
+ .entprlen = 32,
+ .expected = (unsigned char *)
+ "\x1f\x9e\xaf\xe4\xd2\x46\xb7\x47\x41\x4c\x65\x99"
+ "\x01\xe9\x3b\xbb\x83\x0c\x0a\xb0\xc1\x3a\xe2\xb3"
+ "\x31\x4e\xeb\x93\x73\xee\x0b\x26\xc2\x63\xa5\x75"
+ "\x45\x99\xd4\x5c\x9f\xa1\xd4\x45\x87\x6b\x20\x61"
+ "\x40\xea\x78\xa5\x32\xdf\x9e\x66\x17\xaf\xb1\x88"
+ "\x9e\x2e\x23\xdd\xc1\xda\x13\x97\x88\xa5\xb6\x5e"
+ "\x90\x14\x4e\xef\x13\xab\x5c\xd9\x2c\x97\x9e\x7c"
+ "\xd7\xf8\xce\xea\x81\xf5\xcd\x71\x15\x49\x44\xce"
+ "\x83\xb6\x05\xfb\x7d\x30\xb5\x57\x2c\x31\x4f\xfc"
+ "\xfe\x80\xb6\xc0\x13\x0c\x5b\x9b\x2e\x8f\x3d\xfc"
+ "\xc2\xa3\x0c\x11\x1b\x80\x5f\xf3",
+ .expectedlen = 128,
+ .addtla = NULL,
+ .addtlb = NULL,
+ .addtllen = 0,
+ .pers = (unsigned char *)
+ "\x64\xb6\xfc\x60\xbc\x61\x76\x23\x6d\x3f\x4a\x0f"
+ "\xe1\xb4\xd5\x20\x9e\x70\xdd\x03\x53\x6d\xbf\xce"
+ "\xcd\x56\x80\xbc\xb8\x15\xc8\xaa",
+ .perslen = 32,
+ }, {
+ .entropy = (unsigned char *)
+ "\xc7\xcc\xbc\x67\x7e\x21\x66\x1e\x27\x2b\x63\xdd"
+ "\x3a\x78\xdc\xdf\x66\x6d\x3f\x24\xae\xcf\x37\x01"
+ "\xa9\x0d\x89\x8a\xa7\xdc\x81\x58\xae\xb2\x10\x15"
+ "\x7e\x18\x44\x6d\x13\xea\xdf\x37\x85\xfe\x81\xfb",
+ .entropylen = 48,
+ .entpra = (unsigned char *)
+ "\x7b\xa1\x91\x5b\x3c\x04\xc4\x1b\x1d\x19\x2f\x1a"
+ "\x18\x81\x60\x3c\x6c\x62\x91\xb7\xe9\xf5\xcb\x96"
+ "\xbb\x81\x6a\xcc\xb5\xae\x55\xb6",
+ .entprb = (unsigned char *)
+ "\x99\x2c\xc7\x78\x7e\x3b\x88\x12\xef\xbe\xd3\xd2"
+ "\x7d\x2a\xa5\x86\xda\x8d\x58\x73\x4a\x0a\xb2\x2e"
+ "\xbb\x4c\x7e\xe3\x9a\xb6\x81\xc1",
+ .entprlen = 32,
+ .expected = (unsigned char *)
+ "\x95\x6f\x95\xfc\x3b\xb7\xfe\x3e\xd0\x4e\x1a\x14"
+ "\x6c\x34\x7f\x7b\x1d\x0d\x63\x5e\x48\x9c\x69\xe6"
+ "\x46\x07\xd2\x87\xf3\x86\x52\x3d\x98\x27\x5e\xd7"
+ "\x54\xe7\x75\x50\x4f\xfb\x4d\xfd\xac\x2f\x4b\x77"
+ "\xcf\x9e\x8e\xcc\x16\xa2\x24\xcd\x53\xde\x3e\xc5"
+ "\x55\x5d\xd5\x26\x3f\x89\xdf\xca\x8b\x4e\x1e\xb6"
+ "\x88\x78\x63\x5c\xa2\x63\x98\x4e\x6f\x25\x59\xb1"
+ "\x5f\x2b\x23\xb0\x4b\xa5\x18\x5d\xc2\x15\x74\x40"
+ "\x59\x4c\xb4\x1e\xcf\x9a\x36\xfd\x43\xe2\x03\xb8"
+ "\x59\x91\x30\x89\x2a\xc8\x5a\x43\x23\x7c\x73\x72"
+ "\xda\x3f\xad\x2b\xba\x00\x6b\xd1",
+ .expectedlen = 128,
+ .addtla = (unsigned char *)
+ "\x18\xe8\x17\xff\xef\x39\xc7\x41\x5c\x73\x03\x03"
+ "\xf6\x3d\xe8\x5f\xc8\xab\xe4\xab\x0f\xad\xe8\xd6"
+ "\x86\x88\x55\x28\xc1\x69\xdd\x76",
+ .addtlb = (unsigned char *)
+ "\xac\x07\xfc\xbe\x87\x0e\xd3\xea\x1f\x7e\xb8\xe7"
+ "\x9d\xec\xe8\xe7\xbc\xf3\x18\x25\x77\x35\x4a\xaa"
+ "\x00\x99\x2a\xdd\x0a\x00\x50\x82",
+ .addtllen = 32,
+ .pers = (unsigned char *)
+ "\xbc\x55\xab\x3c\xf6\x52\xb0\x11\x3d\x7b\x90\xb8"
+ "\x24\xc9\x26\x4e\x5a\x1e\x77\x0d\x3d\x58\x4a\xda"
+ "\xd1\x81\xe9\xf8\xeb\x30\x8f\x6f",
+ .perslen = 32,
+ },
+};
+
+static struct drbg_testvec drbg_pr_ctr_aes128_tv_template[] = {
+ {
+ .entropy = (unsigned char *)
+ "\xd1\x44\xc6\x61\x81\x6d\xca\x9d\x15\x28\x8a\x42"
+ "\x94\xd7\x28\x9c\x43\x77\x19\x29\x1a\x6d\xc3\xa2",
+ .entropylen = 24,
+ .entpra = (unsigned char *)
+ "\x96\xd8\x9e\x45\x32\xc9\xd2\x08\x7a\x6d\x97\x15"
+ "\xb4\xec\x80\xb1",
+ .entprb = (unsigned char *)
+ "\x8b\xb6\x72\xb5\x24\x0b\x98\x65\x95\x95\xe9\xc9"
+ "\x28\x07\xeb\xc2",
+ .entprlen = 16,
+ .expected = (unsigned char *)
+ "\x70\x19\xd0\x4c\x45\x78\xd6\x68\xa9\x9a\xaa\xfe"
+ "\xc1\xdf\x27\x9a\x1c\x0d\x0d\xf7\x24\x75\x46\xcc"
+ "\x77\x6b\xdf\x89\xc6\x94\xdc\x74\x50\x10\x70\x18"
+ "\x9b\xdc\x96\xb4\x89\x23\x40\x1a\xce\x09\x87\xce"
+ "\xd2\xf3\xd5\xe4\x51\x67\x74\x11\x5a\xcc\x8b\x3b"
+ "\x8a\xf1\x23\xa8",
+ .expectedlen = 64,
+ .addtla = NULL,
+ .addtlb = NULL,
+ .addtllen = 0,
+ .pers = NULL,
+ .perslen = 0,
+ }, {
+ .entropy = (unsigned char *)
+ "\x8e\x83\xe0\xeb\x37\xea\x3e\x53\x5e\x17\x6e\x77"
+ "\xbd\xb1\x53\x90\xfc\xdc\xc1\x3c\x9a\x88\x22\x94",
+ .entropylen = 24,
+ .entpra = (unsigned char *)
+ "\x6a\x85\xe7\x37\xc8\xf1\x04\x31\x98\x4f\xc8\x73"
+ "\x67\xd1\x08\xf8",
+ .entprb = (unsigned char *)
+ "\xd7\xa4\x68\xe2\x12\x74\xc3\xd9\xf1\xb7\x05\xbc"
+ "\xd4\xba\x04\x58",
+ .entprlen = 16,
+ .expected = (unsigned char *)
+ "\x78\xd6\xa6\x70\xff\xd1\x82\xf5\xa2\x88\x7f\x6d"
+ "\x3d\x8c\x39\xb1\xa8\xcb\x2c\x91\xab\x14\x7e\xbc"
+ "\x95\x45\x9f\x24\xb8\x20\xac\x21\x23\xdb\x72\xd7"
+ "\x12\x8d\x48\x95\xf3\x19\x0c\x43\xc6\x19\x45\xfc"
+ "\x8b\xac\x40\x29\x73\x00\x03\x45\x5e\x12\xff\x0c"
+ "\xc1\x02\x41\x82",
+ .expectedlen = 64,
+ .addtla = (unsigned char *)
+ "\xa2\xd9\x38\xcf\x8b\x29\x67\x5b\x65\x62\x6f\xe8"
+ "\xeb\xb3\x01\x76",
+ .addtlb = (unsigned char *)
+ "\x59\x63\x1e\x81\x8a\x14\xa8\xbb\xa1\xb8\x41\x25"
+ "\xd0\x7f\xcc\x43",
+ .addtllen = 16,
+ .pers = NULL,
+ .perslen = 0,
+ }, {
+ .entropy = (unsigned char *)
+ "\x04\xd9\x49\xa6\xdc\xe8\x6e\xbb\xf1\x08\x77\x2b"
+ "\x9e\x08\xca\x92\x65\x16\xda\x99\xa2\x59\xf3\xe8",
+ .entropylen = 24,
+ .entpra = (unsigned char *)
+ "\x38\x7e\x3f\x6b\x51\x70\x7b\x20\xec\x53\xd0\x66"
+ "\xc3\x0f\xe3\xb0",
+ .entprb = (unsigned char *)
+ "\xe0\x86\xa6\xaa\x5f\x72\x2f\xad\xf7\xef\x06\xb8"
+ "\xd6\x9c\x9d\xe8",
+ .entprlen = 16,
+ .expected = (unsigned char *)
+ "\xc9\x0a\xaf\x85\x89\x71\x44\x66\x4f\x25\x0b\x2b"
+ "\xde\xd8\xfa\xff\x52\x5a\x1b\x32\x5e\x41\x7a\x10"
+ "\x1f\xef\x1e\x62\x23\xe9\x20\x30\xc9\x0d\xad\x69"
+ "\xb4\x9c\x5b\xf4\x87\x42\xd5\xae\x5e\x5e\x43\xcc"
+ "\xd9\xfd\x0b\x93\x4a\xe3\xd4\x06\x37\x36\x0f\x3f"
+ "\x72\x82\x0c\xcf",
+ .expectedlen = 64,
+ .addtla = NULL,
+ .addtlb = NULL,
+ .addtllen = 0,
+ .pers = (unsigned char *)
+ "\xbf\xa4\x9a\x8f\x7b\xd8\xb1\x7a\x9d\xfa\x45\xed"
+ "\x21\x52\xb3\xad",
+ .perslen = 16,
+ }, {
+ .entropy = (unsigned char *)
+ "\x92\x89\x8f\x31\xfa\x1c\xff\x6d\x18\x2f\x26\x06"
+ "\x43\xdf\xf8\x18\xc2\xa4\xd9\x72\xc3\xb9\xb6\x97",
+ .entropylen = 24,
+ .entpra = (unsigned char *)
+ "\x20\x72\x8a\x06\xf8\x6f\x8d\xd4\x41\xe2\x72\xb7"
+ "\xc4\x2c\xe8\x10",
+ .entprb = (unsigned char *)
+ "\x3d\xb0\xf0\x94\xf3\x05\x50\x33\x17\x86\x3e\x22"
+ "\x08\xf7\xa5\x01",
+ .entprlen = 16,
+ .expected = (unsigned char *)
+ "\x5a\x35\x39\x87\x0f\x4d\x22\xa4\x09\x24\xee\x71"
+ "\xc9\x6f\xac\x72\x0a\xd6\xf0\x88\x82\xd0\x83\x28"
+ "\x73\xec\x3f\x93\xd8\xab\x45\x23\xf0\x7e\xac\x45"
+ "\x14\x5e\x93\x9f\xb1\xd6\x76\x43\x3d\xb6\xe8\x08"
+ "\x88\xf6\xda\x89\x08\x77\x42\xfe\x1a\xf4\x3f\xc4"
+ "\x23\xc5\x1f\x68",
+ .expectedlen = 64,
+ .addtla = (unsigned char *)
+ "\x1a\x40\xfa\xe3\xcc\x6c\x7c\xa0\xf8\xda\xba\x59"
+ "\x23\x6d\xad\x1d",
+ .addtlb = (unsigned char *)
+ "\x9f\x72\x76\x6c\xc7\x46\xe5\xed\x2e\x53\x20\x12"
+ "\xbc\x59\x31\x8c",
+ .addtllen = 16,
+ .pers = (unsigned char *)
+ "\xea\x65\xee\x60\x26\x4e\x7e\xb6\x0e\x82\x68\xc4"
+ "\x37\x3c\x5c\x0b",
+ .perslen = 16,
+ },
+};
+
+/*
+ * SP800-90A DRBG Test vectors from
+ * http://csrc.nist.gov/groups/STM/cavp/documents/drbg/drbgtestvectors.zip
+ *
+ * Test vectors for DRBG without prediction resistance. All types of DRBGs
+ * (Hash, HMAC, CTR) are tested with all permutations of use cases (w/ and
+ * w/o personalization string, w/ and w/o additional input string).
+ */
+static struct drbg_testvec drbg_nopr_sha256_tv_template[] = {
+ {
+ .entropy = (unsigned char *)
+ "\xa6\x5a\xd0\xf3\x45\xdb\x4e\x0e\xff\xe8\x75\xc3"
+ "\xa2\xe7\x1f\x42\xc7\x12\x9d\x62\x0f\xf5\xc1\x19"
+ "\xa9\xef\x55\xf0\x51\x85\xe0\xfb\x85\x81\xf9\x31"
+ "\x75\x17\x27\x6e\x06\xe9\x60\x7d\xdb\xcb\xcc\x2e",
+ .entropylen = 48,
+ .expected = (unsigned char *)
+ "\xd3\xe1\x60\xc3\x5b\x99\xf3\x40\xb2\x62\x82\x64"
+ "\xd1\x75\x10\x60\xe0\x04\x5d\xa3\x83\xff\x57\xa5"
+ "\x7d\x73\xa6\x73\xd2\xb8\xd8\x0d\xaa\xf6\xa6\xc3"
+ "\x5a\x91\xbb\x45\x79\xd7\x3f\xd0\xc8\xfe\xd1\x11"
+ "\xb0\x39\x13\x06\x82\x8a\xdf\xed\x52\x8f\x01\x81"
+ "\x21\xb3\xfe\xbd\xc3\x43\xe7\x97\xb8\x7d\xbb\x63"
+ "\xdb\x13\x33\xde\xd9\xd1\xec\xe1\x77\xcf\xa6\xb7"
+ "\x1f\xe8\xab\x1d\xa4\x66\x24\xed\x64\x15\xe5\x1c"
+ "\xcd\xe2\xc7\xca\x86\xe2\x83\x99\x0e\xea\xeb\x91"
+ "\x12\x04\x15\x52\x8b\x22\x95\x91\x02\x81\xb0\x2d"
+ "\xd4\x31\xf4\xc9\xf7\x04\x27\xdf",
+ .expectedlen = 128,
+ .addtla = NULL,
+ .addtlb = NULL,
+ .addtllen = 0,
+ .pers = NULL,
+ .perslen = 0,
+ }, {
+ .entropy = (unsigned char *)
+ "\x73\xd3\xfb\xa3\x94\x5f\x2b\x5f\xb9\x8f\xf6\x9c"
+ "\x8a\x93\x17\xae\x19\xc3\x4c\xc3\xd6\xca\xa3\x2d"
+ "\x16\xfc\x42\xd2\x2d\xd5\x6f\x56\xcc\x1d\x30\xff"
+ "\x9e\x06\x3e\x09\xce\x58\xe6\x9a\x35\xb3\xa6\x56",
+ .entropylen = 48,
+ .expected = (unsigned char *)
+ "\x71\x7b\x93\x46\x1a\x40\xaa\x35\xa4\xaa\xc5\xe7"
+ "\x6d\x5b\x5b\x8a\xa0\xdf\x39\x7d\xae\x71\x58\x5b"
+ "\x3c\x7c\xb4\xf0\x89\xfa\x4a\x8c\xa9\x5c\x54\xc0"
+ "\x40\xdf\xbc\xce\x26\x81\x34\xf8\xba\x7d\x1c\xe8"
+ "\xad\x21\xe0\x74\xcf\x48\x84\x30\x1f\xa1\xd5\x4f"
+ "\x81\x42\x2f\xf4\xdb\x0b\x23\xf8\x73\x27\xb8\x1d"
+ "\x42\xf8\x44\x58\xd8\x5b\x29\x27\x0a\xf8\x69\x59"
+ "\xb5\x78\x44\xeb\x9e\xe0\x68\x6f\x42\x9a\xb0\x5b"
+ "\xe0\x4e\xcb\x6a\xaa\xe2\xd2\xd5\x33\x25\x3e\xe0"
+ "\x6c\xc7\x6a\x07\xa5\x03\x83\x9f\xe2\x8b\xd1\x1c"
+ "\x70\xa8\x07\x59\x97\xeb\xf6\xbe",
+ .expectedlen = 128,
+ .addtla = (unsigned char *)
+ "\xf4\xd5\x98\x3d\xa8\xfc\xfa\x37\xb7\x54\x67\x73"
+ "\xc7\xc3\xdd\x47\x34\x71\x02\x5d\xc1\xa0\xd3\x10"
+ "\xc1\x8b\xbd\xf5\x66\x34\x6f\xdd",
+ .addtlb = (unsigned char *)
+ "\xf7\x9e\x6a\x56\x0e\x73\xe9\xd9\x7a\xd1\x69\xe0"
+ "\x6f\x8c\x55\x1c\x44\xd1\xce\x6f\x28\xcc\xa4\x4d"
+ "\xa8\xc0\x85\xd1\x5a\x0c\x59\x40",
+ .addtllen = 32,
+ .pers = NULL,
+ .perslen = 0,
+ }, {
+ .entropy = (unsigned char *)
+ "\x2a\x85\xa9\x8b\xd0\xda\x83\xd6\xad\xab\x9f\xbb"
+ "\x54\x31\x15\x95\x1c\x4d\x49\x9f\x6a\x15\xf6\xe4"
+ "\x15\x50\x88\x06\x29\x0d\xed\x8d\xb9\x6f\x96\xe1"
+ "\x83\x9f\xf7\x88\xda\x84\xbf\x44\x28\xd9\x1d\xaa",
+ .entropylen = 48,
+ .expected = (unsigned char *)
+ "\x2d\x55\xde\xc9\xed\x05\x47\x07\x3d\x04\xfc\x28"
+ "\x0f\x92\xf0\x4d\xd8\x00\x32\x47\x0a\x1b\x1c\x4b"
+ "\xef\xd9\x97\xa1\x17\x67\xda\x26\x6c\xfe\x76\x46"
+ "\x6f\xbc\x6d\x82\x4e\x83\x8a\x98\x66\x6c\x01\xb6"
+ "\xe6\x64\xe0\x08\x10\x6f\xd3\x5d\x90\xe7\x0d\x72"
+ "\xa6\xa7\xe3\xbb\x98\x11\x12\x56\x23\xc2\x6d\xd1"
+ "\xc8\xa8\x7a\x39\xf3\x34\xe3\xb8\xf8\x66\x00\x77"
+ "\x7d\xcf\x3c\x3e\xfa\xc9\x0f\xaf\xe0\x24\xfa\xe9"
+ "\x84\xf9\x6a\x01\xf6\x35\xdb\x5c\xab\x2a\xef\x4e"
+ "\xac\xab\x55\xb8\x9b\xef\x98\x68\xaf\x51\xd8\x16"
+ "\xa5\x5e\xae\xf9\x1e\xd2\xdb\xe6",
+ .expectedlen = 128,
+ .addtla = NULL,
+ .addtlb = NULL,
+ .addtllen = 0,
+ .pers = (unsigned char *)
+ "\xa8\x80\xec\x98\x30\x98\x15\xd2\xc6\xc4\x68\xf1"
+ "\x3a\x1c\xbf\xce\x6a\x40\x14\xeb\x36\x99\x53\xda"
+ "\x57\x6b\xce\xa4\x1c\x66\x3d\xbc",
+ .perslen = 32,
+ }, {
+ .entropy = (unsigned char *)
+ "\x69\xed\x82\xa9\xc5\x7b\xbf\xe5\x1d\x2f\xcb\x7a"
+ "\xd3\x50\x7d\x96\xb4\xb9\x2b\x50\x77\x51\x27\x74"
+ "\x33\x74\xba\xf1\x30\xdf\x8e\xdf\x87\x1d\x87\xbc"
+ "\x96\xb2\xc3\xa7\xed\x60\x5e\x61\x4e\x51\x29\x1a",
+ .entropylen = 48,
+ .expected = (unsigned char *)
+ "\xa5\x71\x24\x31\x11\xfe\x13\xe1\xa8\x24\x12\xfb"
+ "\x37\xa1\x27\xa5\xab\x77\xa1\x9f\xae\x8f\xaf\x13"
+ "\x93\xf7\x53\x85\x91\xb6\x1b\xab\xd4\x6b\xea\xb6"
+ "\xef\xda\x4c\x90\x6e\xef\x5f\xde\xe1\xc7\x10\x36"
+ "\xd5\x67\xbd\x14\xb6\x89\x21\x0c\xc9\x92\x65\x64"
+ "\xd0\xf3\x23\xe0\x7f\xd1\xe8\x75\xc2\x85\x06\xea"
+ "\xca\xc0\xcb\x79\x2d\x29\x82\xfc\xaa\x9a\xc6\x95"
+ "\x7e\xdc\x88\x65\xba\xec\x0e\x16\x87\xec\xa3\x9e"
+ "\xd8\x8c\x80\xab\x3a\x64\xe0\xcb\x0e\x45\x98\xdd"
+ "\x7c\x6c\x6c\x26\x11\x13\xc8\xce\xa9\x47\xa6\x06"
+ "\x57\xa2\x66\xbb\x2d\x7f\xf3\xc1",
+ .expectedlen = 128,
+ .addtla = (unsigned char *)
+ "\x74\xd3\x6d\xda\xe8\xd6\x86\x5f\x63\x01\xfd\xf2"
+ "\x7d\x06\x29\x6d\x94\xd1\x66\xf0\xd2\x72\x67\x4e"
+ "\x77\xc5\x3d\x9e\x03\xe3\xa5\x78",
+ .addtlb = (unsigned char *)
+ "\xf6\xb6\x3d\xf0\x7c\x26\x04\xc5\x8b\xcd\x3e\x6a"
+ "\x9f\x9c\x3a\x2e\xdb\x47\x87\xe5\x8e\x00\x5e\x2b"
+ "\x74\x7f\xa6\xf6\x80\xcd\x9b\x21",
+ .addtllen = 32,
+ .pers = (unsigned char *)
+ "\x74\xa6\xe0\x08\xf9\x27\xee\x1d\x6e\x3c\x28\x20"
+ "\x87\xdd\xd7\x54\x31\x47\x78\x4b\xe5\x6d\xa3\x73"
+ "\xa9\x65\xb1\x10\xc1\xdc\x77\x7c",
+ .perslen = 32,
+ },
+};
+
+static struct drbg_testvec drbg_nopr_hmac_sha256_tv_template[] = {
+ {
+ .entropy = (unsigned char *)
+ "\xca\x85\x19\x11\x34\x93\x84\xbf\xfe\x89\xde\x1c"
+ "\xbd\xc4\x6e\x68\x31\xe4\x4d\x34\xa4\xfb\x93\x5e"
+ "\xe2\x85\xdd\x14\xb7\x1a\x74\x88\x65\x9b\xa9\x6c"
+ "\x60\x1d\xc6\x9f\xc9\x02\x94\x08\x05\xec\x0c\xa8",
+ .entropylen = 48,
+ .expected = (unsigned char *)
+ "\xe5\x28\xe9\xab\xf2\xde\xce\x54\xd4\x7c\x7e\x75"
+ "\xe5\xfe\x30\x21\x49\xf8\x17\xea\x9f\xb4\xbe\xe6"
+ "\xf4\x19\x96\x97\xd0\x4d\x5b\x89\xd5\x4f\xbb\x97"
+ "\x8a\x15\xb5\xc4\x43\xc9\xec\x21\x03\x6d\x24\x60"
+ "\xb6\xf7\x3e\xba\xd0\xdc\x2a\xba\x6e\x62\x4a\xbf"
+ "\x07\x74\x5b\xc1\x07\x69\x4b\xb7\x54\x7b\xb0\x99"
+ "\x5f\x70\xde\x25\xd6\xb2\x9e\x2d\x30\x11\xbb\x19"
+ "\xd2\x76\x76\xc0\x71\x62\xc8\xb5\xcc\xde\x06\x68"
+ "\x96\x1d\xf8\x68\x03\x48\x2c\xb3\x7e\xd6\xd5\xc0"
+ "\xbb\x8d\x50\xcf\x1f\x50\xd4\x76\xaa\x04\x58\xbd"
+ "\xab\xa8\x06\xf4\x8b\xe9\xdc\xb8",
+ .expectedlen = 128,
+ .addtla = NULL,
+ .addtlb = NULL,
+ .addtllen = 0,
+ .pers = NULL,
+ .perslen = 0,
+ }, {
+ .entropy = (unsigned char *)
+ "\xf9\x7a\x3c\xfd\x91\xfa\xa0\x46\xb9\xe6\x1b\x94"
+ "\x93\xd4\x36\xc4\x93\x1f\x60\x4b\x22\xf1\x08\x15"
+ "\x21\xb3\x41\x91\x51\xe8\xff\x06\x11\xf3\xa7\xd4"
+ "\x35\x95\x35\x7d\x58\x12\x0b\xd1\xe2\xdd\x8a\xed",
+ .entropylen = 48,
+ .expected = (unsigned char *)
+ "\xc6\x87\x1c\xff\x08\x24\xfe\x55\xea\x76\x89\xa5"
+ "\x22\x29\x88\x67\x30\x45\x0e\x5d\x36\x2d\xa5\xbf"
+ "\x59\x0d\xcf\x9a\xcd\x67\xfe\xd4\xcb\x32\x10\x7d"
+ "\xf5\xd0\x39\x69\xa6\x6b\x1f\x64\x94\xfd\xf5\xd6"
+ "\x3d\x5b\x4d\x0d\x34\xea\x73\x99\xa0\x7d\x01\x16"
+ "\x12\x6d\x0d\x51\x8c\x7c\x55\xba\x46\xe1\x2f\x62"
+ "\xef\xc8\xfe\x28\xa5\x1c\x9d\x42\x8e\x6d\x37\x1d"
+ "\x73\x97\xab\x31\x9f\xc7\x3d\xed\x47\x22\xe5\xb4"
+ "\xf3\x00\x04\x03\x2a\x61\x28\xdf\x5e\x74\x97\xec"
+ "\xf8\x2c\xa7\xb0\xa5\x0e\x86\x7e\xf6\x72\x8a\x4f"
+ "\x50\x9a\x8c\x85\x90\x87\x03\x9c",
+ .expectedlen = 128,
+ .addtla = (unsigned char *)
+ "\x51\x72\x89\xaf\xe4\x44\xa0\xfe\x5e\xd1\xa4\x1d"
+ "\xbb\xb5\xeb\x17\x15\x00\x79\xbd\xd3\x1e\x29\xcf"
+ "\x2f\xf3\x00\x34\xd8\x26\x8e\x3b",
+ .addtlb = (unsigned char *)
+ "\x88\x02\x8d\x29\xef\x80\xb4\xe6\xf0\xfe\x12\xf9"
+ "\x1d\x74\x49\xfe\x75\x06\x26\x82\xe8\x9c\x57\x14"
+ "\x40\xc0\xc9\xb5\x2c\x42\xa6\xe0",
+ .addtllen = 32,
+ .pers = NULL,
+ .perslen = 0,
+ }, {
+ .entropy = (unsigned char *)
+ "\x8d\xf0\x13\xb4\xd1\x03\x52\x30\x73\x91\x7d\xdf"
+ "\x6a\x86\x97\x93\x05\x9e\x99\x43\xfc\x86\x54\x54"
+ "\x9e\x7a\xb2\x2f\x7c\x29\xf1\x22\xda\x26\x25\xaf"
+ "\x2d\xdd\x4a\xbc\xce\x3c\xf4\xfa\x46\x59\xd8\x4e",
+ .entropylen = 48,
+ .expected = (unsigned char *)
+ "\xb9\x1c\xba\x4c\xc8\x4f\xa2\x5d\xf8\x61\x0b\x81"
+ "\xb6\x41\x40\x27\x68\xa2\x09\x72\x34\x93\x2e\x37"
+ "\xd5\x90\xb1\x15\x4c\xbd\x23\xf9\x74\x52\xe3\x10"
+ "\xe2\x91\xc4\x51\x46\x14\x7f\x0d\xa2\xd8\x17\x61"
+ "\xfe\x90\xfb\xa6\x4f\x94\x41\x9c\x0f\x66\x2b\x28"
+ "\xc1\xed\x94\xda\x48\x7b\xb7\xe7\x3e\xec\x79\x8f"
+ "\xbc\xf9\x81\xb7\x91\xd1\xbe\x4f\x17\x7a\x89\x07"
+ "\xaa\x3c\x40\x16\x43\xa5\xb6\x2b\x87\xb8\x9d\x66"
+ "\xb3\xa6\x0e\x40\xd4\xa8\xe4\xe9\xd8\x2a\xf6\xd2"
+ "\x70\x0e\x6f\x53\x5c\xdb\x51\xf7\x5c\x32\x17\x29"
+ "\x10\x37\x41\x03\x0c\xcc\x3a\x56",
+ .expectedlen = 128,
+ .addtla = NULL,
+ .addtlb = NULL,
+ .addtllen = 0,
+ .pers = (unsigned char *)
+ "\xb5\x71\xe6\x6d\x7c\x33\x8b\xc0\x7b\x76\xad\x37"
+ "\x57\xbb\x2f\x94\x52\xbf\x7e\x07\x43\x7a\xe8\x58"
+ "\x1c\xe7\xbc\x7c\x3a\xc6\x51\xa9",
+ .perslen = 32,
+ }, {
+ .entropy = (unsigned char *)
+ "\xc2\xa5\x66\xa9\xa1\x81\x7b\x15\xc5\xc3\xb7\x78"
+ "\x17\x7a\xc8\x7c\x24\xe7\x97\xbe\x0a\x84\x5f\x11"
+ "\xc2\xfe\x39\x9d\xd3\x77\x32\xf2\xcb\x18\x94\xeb"
+ "\x2b\x97\xb3\xc5\x6e\x62\x83\x29\x51\x6f\x86\xec",
+ .entropylen = 48,
+ .expected = (unsigned char *)
+ "\xb3\xa3\x69\x8d\x77\x76\x99\xa0\xdd\x9f\xa3\xf0"
+ "\xa9\xfa\x57\x83\x2d\x3c\xef\xac\x5d\xf2\x44\x37"
+ "\xc6\xd7\x3a\x0f\xe4\x10\x40\xf1\x72\x90\x38\xae"
+ "\xf1\xe9\x26\x35\x2e\xa5\x9d\xe1\x20\xbf\xb7\xb0"
+ "\x73\x18\x3a\x34\x10\x6e\xfe\xd6\x27\x8f\xf8\xad"
+ "\x84\x4b\xa0\x44\x81\x15\xdf\xdd\xf3\x31\x9a\x82"
+ "\xde\x6b\xb1\x1d\x80\xbd\x87\x1a\x9a\xcd\x35\xc7"
+ "\x36\x45\xe1\x27\x0f\xb9\xfe\x4f\xa8\x8e\xc0\xe4"
+ "\x65\x40\x9e\xa0\xcb\xa8\x09\xfe\x2f\x45\xe0\x49"
+ "\x43\xa2\xe3\x96\xbb\xb7\xdd\x2f\x4e\x07\x95\x30"
+ "\x35\x24\xcc\x9c\xc5\xea\x54\xa1",
+ .expectedlen = 128,
+ .addtla = (unsigned char *)
+ "\x41\x3d\xd8\x3f\xe5\x68\x35\xab\xd4\x78\xcb\x96"
+ "\x93\xd6\x76\x35\x90\x1c\x40\x23\x9a\x26\x64\x62"
+ "\xd3\x13\x3b\x83\xe4\x9c\x82\x0b",
+ .addtlb = (unsigned char *)
+ "\xd5\xc4\xa7\x1f\x9d\x6d\x95\xa1\xbe\xdf\x0b\xd2"
+ "\x24\x7c\x27\x7d\x1f\x84\xa4\xe5\x7a\x4a\x88\x25"
+ "\xb8\x2a\x2d\x09\x7d\xe6\x3e\xf1",
+ .addtllen = 32,
+ .pers = (unsigned char *)
+ "\x13\xce\x4d\x8d\xd2\xdb\x97\x96\xf9\x41\x56\xc8"
+ "\xe8\xf0\x76\x9b\x0a\xa1\xc8\x2c\x13\x23\xb6\x15"
+ "\x36\x60\x3b\xca\x37\xc9\xee\x29",
+ .perslen = 32,
+ },
+};
+
+static struct drbg_testvec drbg_nopr_ctr_aes192_tv_template[] = {
+ {
+ .entropy = (unsigned char *)
+ "\xc3\x5c\x2f\xa2\xa8\x9d\x52\xa1\x1f\xa3\x2a\xa9"
+ "\x6c\x95\xb8\xf1\xc9\xa8\xf9\xcb\x24\x5a\x8b\x40"
+ "\xf3\xa6\xe5\xa7\xfb\xd9\xd3\xc6\x8e\x27\x7b\xa9"
+ "\xac\x9b\xbb\x00",
+ .entropylen = 40,
+ .expected = (unsigned char *)
+ "\x8c\x2e\x72\xab\xfd\x9b\xb8\x28\x4d\xb7\x9e\x17"
+ "\xa4\x3a\x31\x46\xcd\x76\x94\xe3\x52\x49\xfc\x33"
+ "\x83\x91\x4a\x71\x17\xf4\x13\x68\xe6\xd4\xf1\x48"
+ "\xff\x49\xbf\x29\x07\x6b\x50\x15\xc5\x9f\x45\x79"
+ "\x45\x66\x2e\x3d\x35\x03\x84\x3f\x4a\xa5\xa3\xdf"
+ "\x9a\x9d\xf1\x0d",
+ .expectedlen = 64,
+ .addtla = NULL,
+ .addtlb = NULL,
+ .addtllen = 0,
+ .pers = NULL,
+ .perslen = 0,
+ },
+};
+
+static struct drbg_testvec drbg_nopr_ctr_aes256_tv_template[] = {
+ {
+ .entropy = (unsigned char *)
+ "\x36\x40\x19\x40\xfa\x8b\x1f\xba\x91\xa1\x66\x1f"
+ "\x21\x1d\x78\xa0\xb9\x38\x9a\x74\xe5\xbc\xcf\xec"
+ "\xe8\xd7\x66\xaf\x1a\x6d\x3b\x14\x49\x6f\x25\xb0"
+ "\xf1\x30\x1b\x4f\x50\x1b\xe3\x03\x80\xa1\x37\xeb",
+ .entropylen = 48,
+ .expected = (unsigned char *)
+ "\x58\x62\xeb\x38\xbd\x55\x8d\xd9\x78\xa6\x96\xe6"
+ "\xdf\x16\x47\x82\xdd\xd8\x87\xe7\xe9\xa6\xc9\xf3"
+ "\xf1\xfb\xaf\xb7\x89\x41\xb5\x35\xa6\x49\x12\xdf"
+ "\xd2\x24\xc6\xdc\x74\x54\xe5\x25\x0b\x3d\x97\x16"
+ "\x5e\x16\x26\x0c\x2f\xaf\x1c\xc7\x73\x5c\xb7\x5f"
+ "\xb4\xf0\x7e\x1d",
+ .expectedlen = 64,
+ .addtla = NULL,
+ .addtlb = NULL,
+ .addtllen = 0,
+ .pers = NULL,
+ .perslen = 0,
+ },
+};
+
+static struct drbg_testvec drbg_nopr_ctr_aes128_tv_template[] = {
+ {
+ .entropy = (unsigned char *)
+ "\x87\xe1\xc5\x32\x99\x7f\x57\xa3\x5c\x28\x6d\xe8"
+ "\x64\xbf\xf2\x64\xa3\x9e\x98\xdb\x6c\x10\x78\x7f",
+ .entropylen = 24,
+ .expected = (unsigned char *)
+ "\x2c\x14\x7e\x24\x11\x9a\xd8\xd4\xb2\xed\x61\xc1"
+ "\x53\xd0\x50\xc9\x24\xff\x59\x75\x15\xf1\x17\x3a"
+ "\x3d\xf4\x4b\x2c\x84\x28\xef\x89\x0e\xb9\xde\xf3"
+ "\xe4\x78\x04\xb2\xfd\x9b\x35\x7f\xe1\x3f\x8a\x3e"
+ "\x10\xc8\x67\x0a\xf9\xdf\x2d\x6c\x96\xfb\xb2\xb8"
+ "\xcb\x2d\xd6\xb0",
+ .expectedlen = 64,
+ .addtla = NULL,
+ .addtlb = NULL,
+ .addtllen = 0,
+ .pers = NULL,
+ .perslen = 0,
+ }, {
+ .entropy = (unsigned char *)
+ "\x71\xbd\xce\x35\x42\x7d\x20\xbf\x58\xcf\x17\x74"
+ "\xce\x72\xd8\x33\x34\x50\x2d\x8f\x5b\x14\xc4\xdd",
+ .entropylen = 24,
+ .expected = (unsigned char *)
+ "\x97\x33\xe8\x20\x12\xe2\x7b\xa1\x46\x8f\xf2\x34"
+ "\xb3\xc9\xb6\x6b\x20\xb2\x4f\xee\x27\xd8\x0b\x21"
+ "\x8c\xff\x63\x73\x69\x29\xfb\xf3\x85\xcd\x88\x8e"
+ "\x43\x2c\x71\x8b\xa2\x55\xd2\x0f\x1d\x7f\xe3\xe1"
+ "\x2a\xa3\xe9\x2c\x25\x89\xc7\x14\x52\x99\x56\xcc"
+ "\xc3\xdf\xb3\x81",
+ .expectedlen = 64,
+ .addtla = (unsigned char *)
+ "\x66\xef\x42\xd6\x9a\x8c\x3d\x6d\x4a\x9e\x95\xa6"
+ "\x91\x4d\x81\x56",
+ .addtlb = (unsigned char *)
+ "\xe3\x18\x83\xd9\x4b\x5e\xc4\xcc\xaa\x61\x2f\xbb"
+ "\x4a\x55\xd1\xc6",
+ .addtllen = 16,
+ .pers = NULL,
+ .perslen = 0,
+ }, {
+ .entropy = (unsigned char *)
+ "\xca\x4b\x1e\xfa\x75\xbd\x69\x36\x38\x73\xb8\xf9"
+ "\xdb\x4d\x35\x0e\x47\xbf\x6c\x37\x72\xfd\xf7\xa9",
+ .entropylen = 24,
+ .expected = (unsigned char *)
+ "\x59\xc3\x19\x79\x1b\xb1\xf3\x0e\xe9\x34\xae\x6e"
+ "\x8b\x1f\xad\x1f\x74\xca\x25\x45\x68\xb8\x7f\x75"
+ "\x12\xf8\xf2\xab\x4c\x23\x01\x03\x05\xe1\x70\xee"
+ "\x75\xd8\xcb\xeb\x23\x4c\x7a\x23\x6e\x12\x27\xdb"
+ "\x6f\x7a\xac\x3c\x44\xb7\x87\x4b\x65\x56\x74\x45"
+ "\x34\x30\x0c\x3d",
+ .expectedlen = 64,
+ .addtla = NULL,
+ .addtlb = NULL,
+ .addtllen = 0,
+ .pers = (unsigned char *)
+ "\xeb\xaa\x60\x2c\x4d\xbe\x33\xff\x1b\xef\xbf\x0a"
+ "\x0b\xc6\x97\x54",
+ .perslen = 16,
+ }, {
+ .entropy = (unsigned char *)
+ "\xc0\x70\x1f\x92\x50\x75\x8f\xcd\xf2\xbe\x73\x98"
+ "\x80\xdb\x66\xeb\x14\x68\xb4\xa5\x87\x9c\x2d\xa6",
+ .entropylen = 24,
+ .expected = (unsigned char *)
+ "\x97\xc0\xc0\xe5\xa0\xcc\xf2\x4f\x33\x63\x48\x8a"
+ "\xdb\x13\x0a\x35\x89\xbf\x80\x65\x62\xee\x13\x95"
+ "\x7c\x33\xd3\x7d\xf4\x07\x77\x7a\x2b\x65\x0b\x5f"
+ "\x45\x5c\x13\xf1\x90\x77\x7f\xc5\x04\x3f\xcc\x1a"
+ "\x38\xf8\xcd\x1b\xbb\xd5\x57\xd1\x4a\x4c\x2e\x8a"
+ "\x2b\x49\x1e\x5c",
+ .expectedlen = 64,
+ .addtla = (unsigned char *)
+ "\xf9\x01\xf8\x16\x7a\x1d\xff\xde\x8e\x3c\x83\xe2"
+ "\x44\x85\xe7\xfe",
+ .addtlb = (unsigned char *)
+ "\x17\x1c\x09\x38\xc2\x38\x9f\x97\x87\x60\x55\xb4"
+ "\x82\x16\x62\x7f",
+ .addtllen = 16,
+ .pers = (unsigned char *)
+ "\x80\x08\xae\xe8\xe9\x69\x40\xc5\x08\x73\xc7\x9f"
+ "\x8e\xcf\xe0\x02",
+ .perslen = 16,
+ },
+};
+
/* Cast5 test vectors from RFC 2144 */
#define CAST5_ENC_TEST_VECTORS 4
#define CAST5_DEC_TEST_VECTORS 4
^ permalink raw reply related [flat|nested] 29+ messages in thread* [PATCH v2 6/6] Add DRBG test code to testmgr
2014-03-17 7:38 ` [PATCH v2 5/6] DRBG testmgr test vectors Stephan Mueller
@ 2014-03-17 7:39 ` Stephan Mueller
0 siblings, 0 replies; 29+ messages in thread
From: Stephan Mueller @ 2014-03-17 7:39 UTC (permalink / raw)
To: linux-kernel, linux-crypto; +Cc: aquini, jeremy.wayne.powell
The DRBG test code implements the CAVS test approach.
As discussed for the test vectors, all DRBG types are covered with
testing. However, not every backend cipher is covered with testing. To
prevent the testmgr from logging missing testing, the NULL test is
registered for all backend ciphers not covered with specific test cases.
All currently implemented DRBG types and backend ciphers are definined
in SP800-90A. Therefore, the fips_allowed flag is set for all.
Changes to v1:
* Changes due to modification of drbg.c as documented in PATCH 1
* Fix coding style and apply scripts/checkpatch.pl
Signed-off-by: Stephan Mueller <smueller@chronox.de>
---
diff --git a/crypto/testmgr.c b/crypto/testmgr.c
index 7795550..baa6cb7 100644
--- a/crypto/testmgr.c
+++ b/crypto/testmgr.c
@@ -27,6 +27,7 @@
#include <linux/slab.h>
#include <linux/string.h>
#include <crypto/rng.h>
+#include <crypto/drbg.h>
#include "internal.h"
@@ -108,6 +109,11 @@ struct cprng_test_suite {
unsigned int count;
};
+struct drbg_test_suite {
+ struct drbg_testvec *vecs;
+ unsigned int count;
+};
+
struct alg_test_desc {
const char *alg;
int (*test)(const struct alg_test_desc *desc, const char *driver,
@@ -121,6 +127,7 @@ struct alg_test_desc {
struct pcomp_test_suite pcomp;
struct hash_test_suite hash;
struct cprng_test_suite cprng;
+ struct drbg_test_suite drbg;
} suite;
};
@@ -1712,6 +1719,101 @@ static int alg_test_cprng(const struct alg_test_desc *desc, const char *driver,
return err;
}
+
+static int drbg_cavs_test(struct drbg_testvec *test, int pr,
+ const char *driver, u32 type, u32 mask)
+{
+ int ret = -EAGAIN;
+ struct crypto_rng *drng;
+ struct drbg_test_data test_data;
+ struct drbg_string addtl, pers, testentropy;
+ unsigned char *buf = kzalloc(test->expectedlen, GFP_KERNEL);
+
+ if (!buf)
+ return -ENOMEM;
+
+ drng = crypto_alloc_rng(driver, type, mask);
+ if (IS_ERR(drng)) {
+ printk(KERN_ERR "alg: drbg: could not allocate DRNG handle for"
+ "%s\n", driver);
+ kzfree(buf);
+ return -ENOMEM;
+ }
+
+ test_data.testentropy = &testentropy;
+ drbg_string_fill(&testentropy, test->entropy, test->entropylen);
+ drbg_string_fill(&pers, test->pers, test->perslen);
+ ret = crypto_drbg_reset_test(drng, &pers, &test_data);
+ if (ret) {
+ printk(KERN_ERR "alg: drbg: Failed to reset rng\n");
+ goto outbuf;
+ }
+
+ drbg_string_fill(&addtl, test->addtla, test->addtllen);
+ if (pr) {
+ drbg_string_fill(&testentropy, test->entpra, test->entprlen);
+ ret = crypto_drbg_get_bytes_addtl_test(drng,
+ buf, test->expectedlen, &addtl, &test_data);
+ } else {
+ ret = crypto_drbg_get_bytes_addtl(drng,
+ buf, test->expectedlen, &addtl);
+ }
+ if (ret <= 0) {
+ printk(KERN_ERR "alg: drbg: could not obtain random data for"
+ "driver %s\n", driver);
+ goto outbuf;
+ }
+
+ drbg_string_fill(&addtl, test->addtlb, test->addtllen);
+ if (pr) {
+ drbg_string_fill(&testentropy, test->entprb, test->entprlen);
+ ret = crypto_drbg_get_bytes_addtl_test(drng,
+ buf, test->expectedlen, &addtl, &test_data);
+ } else {
+ ret = crypto_drbg_get_bytes_addtl(drng,
+ buf, test->expectedlen, &addtl);
+ }
+ if (ret <= 0) {
+ printk(KERN_ERR "alg: drbg: could not obtain random data for"
+ "driver %s\n", driver);
+ goto outbuf;
+ }
+
+ ret = memcmp(test->expected, buf, test->expectedlen);
+
+outbuf:
+ crypto_free_rng(drng);
+ kzfree(buf);
+ return ret;
+}
+
+
+static int alg_test_drbg(const struct alg_test_desc *desc, const char *driver,
+ u32 type, u32 mask)
+{
+ int err = 0;
+ int pr = 0;
+ int i = 0;
+ struct drbg_testvec *template = desc->suite.drbg.vecs;
+ unsigned int tcount = desc->suite.drbg.count;
+
+ if ((0 == memcmp(driver, "drbg(pr(", 8)) ||
+ (0 == memcmp(driver, "drbg_pr_", 8)))
+ pr = 1;
+
+ for (i = 0; i < tcount; i++) {
+ err = drbg_cavs_test(&template[i], pr, driver, type, mask);
+ if (err) {
+ printk(KERN_ERR "alg: drbg: Test %d failed for %s\n",
+ i, driver);
+ err = -EINVAL;
+ break;
+ }
+ }
+ return err;
+
+}
+
static int alg_test_null(const struct alg_test_desc *desc,
const char *driver, u32 type, u32 mask)
{
@@ -2273,6 +2375,171 @@ static const struct alg_test_desc alg_test_descs[] = {
.alg = "digest_null",
.test = alg_test_null,
}, {
+ .alg = "drbg(nopr(ctr(aes128)))",
+ .test = alg_test_drbg,
+ .fips_allowed = 1,
+ .suite = {
+ .drbg = {
+ .vecs = drbg_nopr_ctr_aes128_tv_template,
+ .count = ARRAY_SIZE(drbg_nopr_ctr_aes128_tv_template)
+ }
+ }
+ }, {
+ .alg = "drbg(nopr(ctr(aes192)))",
+ .test = alg_test_drbg,
+ .fips_allowed = 1,
+ .suite = {
+ .drbg = {
+ .vecs = drbg_nopr_ctr_aes192_tv_template,
+ .count = ARRAY_SIZE(drbg_nopr_ctr_aes192_tv_template)
+ }
+ }
+ }, {
+ .alg = "drbg(nopr(ctr(aes256)))",
+ .test = alg_test_drbg,
+ .fips_allowed = 1,
+ .suite = {
+ .drbg = {
+ .vecs = drbg_nopr_ctr_aes256_tv_template,
+ .count = ARRAY_SIZE(drbg_nopr_ctr_aes256_tv_template)
+ }
+ }
+ }, {
+ /* There is no need to specifically test the DRBG with every
+ * backend cipher -- covered by drbg(nopr(hmac(sha256))) test */
+ .alg = "drbg(nopr(hmac(sha1)))",
+ .fips_allowed = 1,
+ .test = alg_test_null,
+ }, {
+ .alg = "drbg(nopr(hmac(sha256)))",
+ .test = alg_test_drbg,
+ .fips_allowed = 1,
+ .suite = {
+ .drbg = {
+ .vecs = drbg_nopr_hmac_sha256_tv_template,
+ .count =
+ ARRAY_SIZE(drbg_nopr_hmac_sha256_tv_template)
+ }
+ }
+ }, {
+ /* There is no need to specifically test the DRBG with every
+ * backend cipher -- covered by drbg(nopr(hmac(sha256))) test */
+ .alg = "drbg(nopr(hmac(sha384)))",
+ .fips_allowed = 1,
+ .test = alg_test_null,
+ }, {
+ /* There is no need to specifically test the DRBG with every
+ * backend cipher -- covered by drbg(nopr(hmac(sha256))) test */
+ .alg = "drbg(nopr(hmac(sha512)))",
+ .test = alg_test_null,
+ .fips_allowed = 1,
+ }, {
+ /* There is no need to specifically test the DRBG with every
+ * backend cipher -- covered by drbg(nopr(sha256)) test */
+ .alg = "drbg(nopr(sha1))",
+ .fips_allowed = 1,
+ .test = alg_test_null,
+ }, {
+ .alg = "drbg(nopr(sha256))",
+ .test = alg_test_drbg,
+ .fips_allowed = 1,
+ .suite = {
+ .drbg = {
+ .vecs = drbg_nopr_sha256_tv_template,
+ .count = ARRAY_SIZE(drbg_nopr_sha256_tv_template)
+ }
+ }
+ }, {
+ /* There is no need to specifically test the DRBG with every
+ * backend cipher -- covered by drbg(nopr(sha256)) test */
+ .alg = "drbg(nopr(sha384))",
+ .fips_allowed = 1,
+ .test = alg_test_null,
+ }, {
+ /* There is no need to specifically test the DRBG with every
+ * backend cipher -- covered by drbg(nopr(sha256)) test */
+ .alg = "drbg(nopr(sha512))",
+ .fips_allowed = 1,
+ .test = alg_test_null,
+ }, {
+ .alg = "drbg(pr(ctr(aes128)))",
+ .test = alg_test_drbg,
+ .fips_allowed = 1,
+ .suite = {
+ .drbg = {
+ .vecs = drbg_pr_ctr_aes128_tv_template,
+ .count = ARRAY_SIZE(drbg_pr_ctr_aes128_tv_template)
+ }
+ }
+ }, {
+ /* There is no need to specifically test the DRBG with every
+ * backend cipher -- covered by drbg(pr(aes128)) test */
+ .alg = "drbg(pr(ctr(aes192)))",
+ .fips_allowed = 1,
+ .test = alg_test_null,
+ }, {
+ /* There is no need to specifically test the DRBG with every
+ * backend cipher -- covered by drbg(pr(aes128)) test */
+ .alg = "drbg(pr(ctr(aes256)))",
+ .fips_allowed = 1,
+ .test = alg_test_null,
+ }, {
+ /* There is no need to specifically test the DRBG with every
+ * backend cipher -- covered by drbg(pr(hmac(sha256))) test */
+ .alg = "drbg(pr(hmac(sha1)))",
+ .fips_allowed = 1,
+ .test = alg_test_null,
+ }, {
+ .alg = "drbg(pr(hmac(sha256)))",
+ .test = alg_test_drbg,
+ .fips_allowed = 1,
+ .suite = {
+ .drbg = {
+ .vecs = drbg_pr_hmac_sha256_tv_template,
+ .count = ARRAY_SIZE(drbg_pr_hmac_sha256_tv_template)
+ }
+ }
+ }, {
+ /* There is no need to specifically test the DRBG with every
+ * backend cipher -- covered by drbg(pr(hmac(sha256))) test */
+ .alg = "drbg(pr(hmac(sha384)))",
+ .fips_allowed = 1,
+ .test = alg_test_null,
+ }, {
+ /* There is no need to specifically test the DRBG with every
+ * backend cipher -- covered by drbg(pr(hmac(sha256))) test */
+ .alg = "drbg(pr(hmac(sha512)))",
+ .test = alg_test_null,
+ .fips_allowed = 1,
+ }, {
+ /* There is no need to specifically test the DRBG with every
+ * backend cipher -- covered by drbg(pr(sha256)) test */
+ .alg = "drbg(pr(sha1))",
+ .fips_allowed = 1,
+ .test = alg_test_null,
+ }, {
+ .alg = "drbg(pr(sha256))",
+ .test = alg_test_drbg,
+ .fips_allowed = 1,
+ .suite = {
+ .drbg = {
+ .vecs = drbg_pr_sha256_tv_template,
+ .count = ARRAY_SIZE(drbg_pr_sha256_tv_template)
+ }
+ }
+ }, {
+ /* There is no need to specifically test the DRBG with every
+ * backend cipher -- covered by drbg(pr(sha256)) test */
+ .alg = "drbg(pr(sha384))",
+ .fips_allowed = 1,
+ .test = alg_test_null,
+ }, {
+ /* There is no need to specifically test the DRBG with every
+ * backend cipher -- covered by drbg(pr(sha256)) test */
+ .alg = "drbg(pr(sha512))",
+ .fips_allowed = 1,
+ .test = alg_test_null,
+ }, {
.alg = "ecb(__aes-aesni)",
.test = alg_test_null,
.fips_allowed = 1,
^ permalink raw reply related [flat|nested] 29+ messages in thread
* [PATCH v4 2/6] header file for DRBG
2014-03-17 7:35 ` [PATCH v2 2/6] header file for DRBG Stephan Mueller
2014-03-17 7:35 ` [PATCH v2 3/6] DRBG kernel configuration options Stephan Mueller
@ 2014-04-11 18:07 ` Stephan Mueller
1 sibling, 0 replies; 29+ messages in thread
From: Stephan Mueller @ 2014-04-11 18:07 UTC (permalink / raw)
To: linux-kernel, linux-crypto; +Cc: aquini, jeremy.wayne.powell, clemens, pwalten
Changes v4:
* change return codes of generate functions to signed int to convey error
codes and to match the kernel crypto API expecations on the generate
function.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
---
create mode 100644 include/crypto/drbg.h
diff --git a/include/crypto/drbg.h b/include/crypto/drbg.h
new file mode 100644
index 0000000..3fe1613
--- /dev/null
+++ b/include/crypto/drbg.h
@@ -0,0 +1,292 @@
+/*
+ * DRBG based on NIST SP800-90A
+ *
+ * Copyright Stephan Mueller <smueller@chronox.de>, 2014
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, and the entire permission notice in its entirety,
+ * including the disclaimer of warranties.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote
+ * products derived from this software without specific prior
+ * written permission.
+ *
+ * ALTERNATIVELY, this product may be distributed under the terms of
+ * the GNU General Public License, in which case the provisions of the GPL are
+ * required INSTEAD OF the above restrictions. (This clause is
+ * necessary due to a potential bad interaction between the GPL and
+ * the restrictions contained in a BSD-style copyright.)
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF
+ * WHICH ARE HEREBY DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+ * USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ */
+
+#ifndef _DRBG_H
+#define _DRBG_H
+
+
+#include <linux/random.h>
+#include <linux/scatterlist.h>
+#include <crypto/hash.h>
+#include <linux/module.h>
+#include <linux/crypto.h>
+#include <linux/slab.h> /* needed for kzalloc */
+#include <crypto/internal/rng.h>
+#include <crypto/rng.h>
+#include <linux/fips.h>
+#include <linux/spinlock.h>
+
+/*
+ * Concatenation Helper and string operation helper
+ *
+ * SP800-90A requires the concatenation of different data. To avoid copying
+ * buffers around or allocate additional memory, the following data structure
+ * is used to point to the original memory with its size. In addition, it
+ * is used to build a linked list. The linked list defines the concatenation
+ * of individual buffers. The order of memory block referenced in that
+ * linked list determines the order of concatenation.
+ */
+
+struct drbg_string {
+ const unsigned char *buf;
+ size_t len;
+ struct drbg_string *next;
+};
+
+static inline void drbg_string_fill(struct drbg_string *string,
+ const unsigned char *buf, size_t len)
+{
+ string->buf = buf;
+ string->len = len;
+ string->next = NULL;
+}
+
+struct drbg_state;
+typedef uint32_t drbg_flag_t;
+
+struct drbg_core {
+ drbg_flag_t flags; /* flags for the cipher */
+ __u8 statelen; /* maximum state length */
+ __u8 max_addtllen; /* maximum length of personalization string or
+ additional input string -- exponent for base
+ 2 */
+ __u8 max_bits; /* maximum bits per RNG request -- exponent for
+ base 2*/
+ __u8 max_req; /* maximum number of requests -- exponent for
+ base 2 */
+ __u8 blocklen_bytes; /* block size of output in bytes */
+ char cra_name[CRYPTO_MAX_ALG_NAME]; /* mapping to kernel crypto API */
+ char cra_driver_name[CRYPTO_MAX_ALG_NAME]; /* mapping to kernel crypto
+ * API */
+ char backend_cra_name[CRYPTO_MAX_ALG_NAME]; /* kernel crypto API
+ * backend cipher name */
+};
+
+struct drbg_state_ops {
+ int (*update)(struct drbg_state *drbg, struct drbg_string *seed,
+ int reseed);
+ int (*generate)(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl);
+ int (*crypto_init)(struct drbg_state *drbg);
+ int (*crypto_fini)(struct drbg_state *drbg);
+
+};
+
+struct drbg_test_data {
+ struct drbg_string *testentropy; /* TEST PARAMETER: test entropy */
+};
+
+struct drbg_state {
+ spinlock_t drbg_lock; /* lock around DRBG */
+ unsigned char *V; /* internal state 10.1.1.1 1a) */
+ unsigned char *C; /* hash: static value 10.1.1.1 1b)
+ * hmac / ctr: key */
+ size_t reseed_ctr; /* Number of RNG requests since last reseed --
+ * 10.1.1.1 1c) */
+ unsigned char *scratchpad; /* some memory the DRBG can use for its
+ * operation -- allocated during init */
+ void *priv_data; /* Data needed for specific cipher
+ * implementation */
+ bool seeded; /* DRBG fully seeded? */
+ bool pr; /* Prediction resistance enabled? */
+#ifdef CONFIG_CRYPTO_FIPS
+ bool fips_primed; /* Continuous test primed? */
+ unsigned char *prev; /* previous output value of DRBG_BLOCKLEN for
+ * FIPS 140-2 continuous test */
+#endif
+ const struct drbg_state_ops *d_ops;
+ const struct drbg_core *core;
+ struct drbg_test_data *test_data;
+};
+
+/* helper functions */
+static inline __u8 drbg_statelen(struct drbg_state *drbg)
+{
+ if (drbg && drbg->core)
+ return drbg->core->statelen;
+ return 0;
+}
+
+static inline __u8 drbg_blocklen(struct drbg_state *drbg)
+{
+ if (drbg && drbg->core)
+ return drbg->core->blocklen_bytes;
+ return 0;
+}
+
+static inline __u8 drbg_keylen(struct drbg_state *drbg)
+{
+ if (drbg && drbg->core)
+ return (drbg->core->statelen - drbg->core->blocklen_bytes);
+ return 0;
+}
+
+static inline size_t drbg_max_request_bytes(struct drbg_state *drbg)
+{
+ /* max_bits is in bits, but buflen is in bytes */
+ return (1 << (drbg->core->max_bits - 3));
+}
+
+static inline size_t drbg_max_addtl(struct drbg_state *drbg)
+{
+ return (1UL<<(drbg->core->max_addtllen));
+}
+
+static inline size_t drbg_max_requests(struct drbg_state *drbg)
+{
+ return (1UL<<(drbg->core->max_req));
+}
+
+/* kernel crypto API input data structure for DRBG generate in case dlen
+ * is set to 0 */
+struct drbg_gen {
+ unsigned char *outbuf; /* output buffer for random numbers */
+ unsigned int outlen; /* size of output buffer */
+ struct drbg_string *addtl; /* input buffer for
+ * additional information string */
+ struct drbg_test_data *test_data; /* test data */
+};
+
+/*
+ * This is a wrapper to the kernel crypto API function of
+ * crypto_rng_get_bytes() to allow the caller to provide additional data
+ *
+ * @drng DRBG handle -- see crypto_rng_get_bytes
+ * @outbuf output buffer -- see crypto_rng_get_bytes
+ * @outlen length of output buffer -- see crypto_rng_get_bytes
+ * @addtl_input additional information string input buffer
+ * @addtllen length of additional information string buffer
+ *
+ * return
+ * see crypto_rng_get_bytes
+ */
+static inline int crypto_drbg_get_bytes_addtl(struct crypto_rng *drng,
+ unsigned char *outbuf, unsigned int outlen,
+ struct drbg_string *addtl)
+{
+ int ret;
+ struct drbg_gen genbuf;
+ genbuf.outbuf = outbuf;
+ genbuf.outlen = outlen;
+ genbuf.addtl = addtl;
+ genbuf.test_data = NULL;
+ ret = crypto_rng_get_bytes(drng, (u8 *)&genbuf, 0);
+ return ret;
+}
+
+/*
+ * TEST code
+ *
+ * This is a wrapper to the kernel crypto API function of
+ * crypto_rng_get_bytes() to allow the caller to provide additional data and
+ * allow furnishing of test_data
+ *
+ * @drng DRBG handle -- see crypto_rng_get_bytes
+ * @outbuf output buffer -- see crypto_rng_get_bytes
+ * @outlen length of output buffer -- see crypto_rng_get_bytes
+ * @addtl_input additional information string input buffer
+ * @addtllen length of additional information string buffer
+ * @test_data filled test data
+ *
+ * return
+ * see crypto_rng_get_bytes
+ */
+static inline int crypto_drbg_get_bytes_addtl_test(struct crypto_rng *drng,
+ unsigned char *outbuf, unsigned int outlen,
+ struct drbg_string *addtl,
+ struct drbg_test_data *test_data)
+{
+ int ret;
+ struct drbg_gen genbuf;
+ genbuf.outbuf = outbuf;
+ genbuf.outlen = outlen;
+ genbuf.addtl = addtl;
+ genbuf.test_data = test_data;
+ ret = crypto_rng_get_bytes(drng, (u8 *)&genbuf, 0);
+ return ret;
+}
+
+/*
+ * TEST code
+ *
+ * This is a wrapper to the kernel crypto API function of
+ * crypto_rng_reset() to allow the caller to provide test_data
+ *
+ * @drng DRBG handle -- see crypto_rng_reset
+ * @pers personalization string input buffer
+ * @perslen length of additional information string buffer
+ * @test_data filled test data
+ *
+ * return
+ * see crypto_rng_reset
+ */
+static inline int crypto_drbg_reset_test(struct crypto_rng *drng,
+ struct drbg_string *pers,
+ struct drbg_test_data *test_data)
+{
+ int ret;
+ struct drbg_gen genbuf;
+ genbuf.outbuf = NULL;
+ genbuf.outlen = 0;
+ genbuf.addtl = pers;
+ genbuf.test_data = test_data;
+ ret = crypto_rng_reset(drng, (u8 *)&genbuf, 0);
+ return ret;
+}
+
+/* DRBG type flags */
+#define DRBG_CTR ((drbg_flag_t)1<<0)
+#define DRBG_HMAC ((drbg_flag_t)1<<1)
+#define DRBG_HASH ((drbg_flag_t)1<<2)
+#define DRBG_TYPE_MASK (DRBG_CTR | DRBG_HMAC | DRBG_HASH)
+/* DRBG strength flags */
+#define DRBG_STRENGTH128 ((drbg_flag_t)1<<3)
+#define DRBG_STRENGTH192 ((drbg_flag_t)1<<4)
+#define DRBG_STRENGTH256 ((drbg_flag_t)1<<5)
+#define DRBG_STRENGTH_MASK (DRBG_STRENGTH128 | DRBG_STRENGTH192 | \
+ DRBG_STRENGTH256)
+
+enum drbg_prefixes {
+ DRBG_PREFIX0 = 0x00,
+ DRBG_PREFIX1,
+ DRBG_PREFIX2,
+ DRBG_PREFIX3
+};
+
+#endif /* _DRBG_H */
^ permalink raw reply related [flat|nested] 29+ messages in thread
* Re: [PATCH v2 1/6] SP800-90A Deterministic Random Bit Generator
2014-03-17 7:34 ` [PATCH v2 " Stephan Mueller
2014-03-17 7:35 ` [PATCH v2 2/6] header file for DRBG Stephan Mueller
@ 2014-03-19 7:51 ` Stephan Mueller
2014-03-20 8:12 ` Clemens Ladisch
` (2 subsequent siblings)
4 siblings, 0 replies; 29+ messages in thread
From: Stephan Mueller @ 2014-03-19 7:51 UTC (permalink / raw)
To: linux-kernel, linux-crypto; +Cc: aquini, jeremy.wayne.powell
Am Montag, 17. März 2014, 08:34:06 schrieb Stephan Mueller:
> +static int drbg_seed(struct drbg_state *drbg, struct drbg_string *pers,
> + bool reseed)
> +{
> + int ret = 0;
> + unsigned char *entropy = NULL;
> + size_t entropylen = 0;
> + struct drbg_string data1;
> + struct drbg_string *data2;
> +
> + /* 9.1 / 9.2 / 9.3.1 step 3 */
> + if (pers && pers->len > (drbg_max_addtl(drbg)))
> + return -EINVAL;
> +
> + if (drbg->test_data) {
> + data1.buf = drbg->test_data->testentropy->buf;
> + data1.len = drbg->test_data->testentropy->len;
> + data1.next = NULL;
> + } else {
> + /* Gather entropy equal to the security strength of the DRBG.
> + * With a derivation function, a nonce is required in addition
> + * to the entropy. A nonce must be at least 1/2 of the
security
> + * strength of the DRBG in size. Thus, entropy * nonce is 3/2
> + * of the strength. The consideration of a nonce is only
> + * applicable during initial seeding. */
> + entropylen = (drbg_sec_strength(drbg->core->flags) / 8);
drbg_sec_strength returns the strength in bytes, thus the division by 8 must
be removed
> + if (!entropylen)
> + return -EFAULT;
> + if (!reseed)
> + /* make sure we round up strength/2 in
> + * case it is not divisible by 2 */
> + entropylen = ((entropylen + 1) / 2) * 3;
> +
> + entropy = kzalloc(entropylen, GFP_KERNEL);
> + if (!entropy)
> + return -ENOMEM;
> + get_random_bytes(entropy, entropylen);
> + drbg_string_fill(&data1, entropy, entropylen);
> + }
> +
> + /* concatenation of entropy with personalization str / addtl input) */
> + if (pers && 0 < pers->len) {
> + data2 = pers;
> + data2->next = NULL;
> + data1.next = data2;
> + }
> +
> + ret = drbg->d_ops->update(drbg, &data1, reseed);
> + if (ret)
> + goto out;
> +
> + drbg->seeded = true;
> + /* 10.1.1.2 / 10.1.1.3 step 5 */
> + drbg->reseed_ctr = 1;
> +
> +out:
> + if (entropy)
> + kzfree(entropy);
> + return ret;
> +}
> +
[...]
> +static unsigned int drbg_generate(struct drbg_state *drbg,
> + unsigned char *buf, unsigned int buflen,
> + struct drbg_string *addtl)
> +{
> + unsigned int len = 0;
> + struct drbg_state *shadow = NULL;
> +
> + if (0 == buflen || !buf)
> + return 0;
> + if (addtl && NULL == addtl->buf && 0 < addtl->len)
> + return 0;
> +
> + if (drbg_make_shadow(drbg, &shadow))
> + return 0;
> + /* 9.3.1 step 2 */
> + if (buflen > (drbg_max_request_bytes(shadow)))
> + goto err;
> + /* 9.3.1 step 3 is implicit with the chosen DRBG */
> + /* 9.3.1 step 4 */
> + if (addtl && addtl->len > (drbg_max_addtl(shadow)))
> + goto err;
> + /* 9.3.1 step 5 is implicit with the chosen DRBG */
> + /* 9.3.1 step 6 and 9 supplemented by 9.3.2 step c -- the spec is a
> + * bit convoluted here, we make it simpler */
> + if ((drbg_max_requests(shadow)) < shadow->reseed_ctr)
> + shadow->seeded = false;
> +
> + /* allocate cipher handle */
> + if (shadow->d_ops->crypto_init && shadow->d_ops->crypto_init(shadow))
> + goto err;
> +
> + if (shadow->pr || !shadow->seeded) {
> + /* 9.3.1 steps 7.1 through 7.3 */
> + if (drbg_seed(shadow, addtl, true))
> + goto err;
> + /* 9.3.1 step 7.4 */
> + addtl = NULL;
> + }
> + /* 9.3.1 step 8 and 10 */
> + len = drbg->d_ops->generate(shadow, buf, buflen, addtl);
This needs to be shadow->d_ops
> +
> + /* 10.1.1.4 step 6, 10.1.2.5 step 7, 10.2.1.5.2 step 7 */
> + shadow->reseed_ctr++;
> +
> +err:
> + if (shadow->d_ops->crypto_fini)
> + shadow->d_ops->crypto_fini(shadow);
> + drbg_restore_shadow(drbg, &shadow);
> + return len;
> +}
Ciao
Stephan
^ permalink raw reply [flat|nested] 29+ messages in thread* Re: [PATCH v2 1/6] SP800-90A Deterministic Random Bit Generator
2014-03-17 7:34 ` [PATCH v2 " Stephan Mueller
2014-03-17 7:35 ` [PATCH v2 2/6] header file for DRBG Stephan Mueller
2014-03-19 7:51 ` [PATCH v2 1/6] SP800-90A Deterministic Random Bit Generator Stephan Mueller
@ 2014-03-20 8:12 ` Clemens Ladisch
2014-03-20 13:30 ` Stephan Mueller
2014-03-27 19:53 ` [PATCH v3 " Stephan Mueller
2014-03-27 19:56 ` Stephan Mueller
4 siblings, 1 reply; 29+ messages in thread
From: Clemens Ladisch @ 2014-03-20 8:12 UTC (permalink / raw)
To: Stephan Mueller, linux-kernel, linux-crypto; +Cc: aquini, jeremy.wayne.powell
Stephan Mueller wrote:
> This is a clean-room implementation of the DRBG defined in SP800-90A.
Why? I guess it's for certification?
> +static bool drbg_fips_continuous_test(struct drbg_state *drbg,
> + unsigned char *buf)
> ...
> + ret = memcmp(drbg->prev, buf, drbg_blocklen(drbg));
> + ...
> + /* invert the memcmp result, because the test shall pass when the
> + * two compared values do not match */
> + if (ret)
> + return true;
> + else
> + return false;
This looks strange. The return value of memcmp() is not really
a boolean, and the code appears not to match the comment because the
numeric value of ret is not actually inverted. How about this:
ret = memcmp(...);
...
/* the test shall pass when the compared values are not equal */
return ret != 0;
Regards,
Clemens
^ permalink raw reply [flat|nested] 29+ messages in thread
* Re: [PATCH v2 1/6] SP800-90A Deterministic Random Bit Generator
2014-03-20 8:12 ` Clemens Ladisch
@ 2014-03-20 13:30 ` Stephan Mueller
0 siblings, 0 replies; 29+ messages in thread
From: Stephan Mueller @ 2014-03-20 13:30 UTC (permalink / raw)
To: Clemens Ladisch; +Cc: linux-kernel, linux-crypto, aquini, jeremy.wayne.powell
Am Donnerstag, 20. März 2014, 09:12:55 schrieb Clemens Ladisch:
Hi Clemens,
> Stephan Mueller wrote:
> > This is a clean-room implementation of the DRBG defined in SP800-90A.
>
> Why? I guess it's for certification?
As per SP800-131A, the ANSI X9.31 DRNG is sunset by the end of 2014 and not
allowed to be used in FIPS 140-2 compliant environments. The kernel crypto API
implements an ANSI X9.31 DRNG in crypto/ansi_cprng.c as the only DRNG that
complies with FIPS 140-2 at this time.
Without a replacement for this ANSI X9.31 DRNG, the kernel will not have an
FIPS 140-2 approved DRNG any more starting from 2015.
>
> > +static bool drbg_fips_continuous_test(struct drbg_state *drbg,
> > + unsigned char *buf)
> > ...
> > + ret = memcmp(drbg->prev, buf, drbg_blocklen(drbg));
> > + ...
> > + /* invert the memcmp result, because the test shall pass when the
> > + * two compared values do not match */
> > + if (ret)
> > + return true;
> > + else
> > + return false;
>
> This looks strange. The return value of memcmp() is not really
> a boolean, and the code appears not to match the comment because the
> numeric value of ret is not actually inverted. How about this:
Correct, the comment does not match the code as I had invered the logic of
drbg_fips_continuous_test as per Rafael's comment. Yet, I did not update the
comment.
>
> ret = memcmp(...);
> ...
> /* the test shall pass when the compared values are not equal */
> return ret != 0;
I will add that change.
>
>
> Regards,
> Clemens
Thanks
Stephan
--
| Cui bono? |
^ permalink raw reply [flat|nested] 29+ messages in thread
* [PATCH v3 1/6] SP800-90A Deterministic Random Bit Generator
2014-03-17 7:34 ` [PATCH v2 " Stephan Mueller
` (2 preceding siblings ...)
2014-03-20 8:12 ` Clemens Ladisch
@ 2014-03-27 19:53 ` Stephan Mueller
2014-03-27 19:56 ` Stephan Mueller
4 siblings, 0 replies; 29+ messages in thread
From: Stephan Mueller @ 2014-03-27 19:53 UTC (permalink / raw)
To: linux-kernel, linux-crypto; +Cc: aquini, jeremy.wayne.powell, clemens, pwalten
Changes v3:
* fix invocation of drbg_sec_strength to determine the amount of seed needed
for the DRBG. The function returns information as a byte value, but the
invoker assumed a bit value.
* change default value returned by drbg_sec_strength to be the maximum entropy
defined by SP800-90A to catch erroneous invocations of the function.
* Fix invocaction of d_ops in drbg_generate: drbg->d_ops ==> shadow->d_ops
* Make return of drbg_fips_continuous_test cleaner as suggested by
Clemens Ladisch
* Fix comments on how to invoke the DRBG at the beginning of the file
* drbg_ctr_df: replace the for loop for calculation of padlen that used to
call up to 16 modulo operations with one modulo operation
* drbg_ctr_df: replace plain integer values with sizeof() to make code clearer
* drbg_hash_hashgen: replace memset() on drbg->scratchpad with memset()
on src/dst pointers to make code clearer
* as recommended by Peter Waltenberg: add re-invocation of self tests as
required by 11.3.3 -- the tests are commented out because they make no
mathematical sense. However, if a FIPS 140-2 validation requires these
tests, the code just needs to be activated.
* as recommended by Peter Waltenberg: add error path tests as required by
11.3.2 -- see new function of drbg_healthcheck_sanity
* add debug printk
* perform testing in FIPS 140-2 mode
* as recommended by Peter Waltenberg: add drbg_generate_long to generate
arbitrary long strings
Signed-off-by: Stephan Mueller <smueller@chronox.de>
---
create mode 100644 crypto/drbg.c
diff --git a/crypto/drbg.c b/crypto/drbg.c
new file mode 100644
index 0000000..6c866ef
--- /dev/null
+++ b/crypto/drbg.c
@@ -0,0 +1,1975 @@
+/*
+ * DRBG: Deterministic Random Bits Generator
+ * Based on NIST Recommended DRBG from NIST SP800-90A with the following
+ * properties:
+ * * CTR DRBG with DF with AES-128, AES-192, AES-256 cores
+ * * Hash DRBG with DF with SHA-1, SHA-256, SHA-384, SHA-512 cores
+ * * HMAC DRBG with DF with SHA-1, SHA-256, SHA-384, SHA-512 cores
+ * * with and without prediction resistance
+ *
+ * Copyright Stephan Mueller <smueller@chronox.de>, 2014
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, and the entire permission notice in its entirety,
+ * including the disclaimer of warranties.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote
+ * products derived from this software without specific prior
+ * written permission.
+ *
+ * ALTERNATIVELY, this product may be distributed under the terms of
+ * the GNU General Public License, in which case the provisions of the GPL are
+ * required INSTEAD OF the above restrictions. (This clause is
+ * necessary due to a potential bad interaction between the GPL and
+ * the restrictions contained in a BSD-style copyright.)
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF
+ * WHICH ARE HEREBY DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+ * USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * DRBG Usage
+ * ==========
+ * The SP 800-90A DRBG allows the user to specify a personalization string
+ * for initialization as well as an additional information string for each
+ * random number request. The following code fragments show how a caller
+ * uses the kernel crypto API to use the full functionality of the DRBG.
+ *
+ * Usage without any additional data
+ * ---------------------------------
+ * struct crypto_rng *drng;
+ * int err;
+ * char data[DATALEN];
+ *
+ * drng = crypto_alloc_rng(drng_name, 0, 0);
+ * err = crypto_rng_get_bytes(drng, &data, DATALEN);
+ * crypto_free_rng(drng);
+ *
+ *
+ * Usage with personalization string during initialization
+ * -------------------------------------------------------
+ * struct crypto_rng *drng;
+ * int err;
+ * char data[DATALEN];
+ * struct drbg_string pers;
+ * char personalization[11] = "some-string";
+ *
+ * drbg_string_fill(&pers, personalization, strlen(personalization));
+ * drng = crypto_alloc_rng(drng_name, 0, 0);
+ * // The reset completely re-initializes the DRBG with the provided
+ * // personalization string
+ * err = crypto_rng_reset(drng, &personalization, strlen(personalization));
+ * err = crypto_rng_get_bytes(drng, &data, DATALEN);
+ * crypto_free_rng(drng);
+ *
+ *
+ * Usage with additional information string during random number request
+ * ---------------------------------------------------------------------
+ * struct crypto_rng *drng;
+ * int err;
+ * char data[DATALEN];
+ * char addtl_string[11] = "some-string";
+ * string drbg_string addtl;
+ *
+ * drbg_string_fill(&addtl, addtl_string, strlen(addtl_string));
+ * drng = crypto_alloc_rng(drng_name, 0, 0);
+ * // The following call is a wrapper to crypto_rng_get_bytes() and returns
+ * // the same error codes.
+ * err = crypto_drbg_get_bytes_addtl(drng, &data, DATALEN, &addtl);
+ * crypto_free_rng(drng);
+ *
+ *
+ * Usage with personalization and additional information strings
+ * -------------------------------------------------------------
+ * Just mix both scenarios above.
+ */
+
+#include <crypto/drbg.h>
+
+#if !defined(CONFIG_CRYPTO_DRBG_HASH) && \
+ !defined(CONFIG_CRYPTO_DRBG_HMAC) && \
+ !defined(CONFIG_CRYPTO_DRBG_CTR)
+#warning "The DRBG code is useless without compiling at least one DRBG type"
+#endif
+
+/***************************************************************
+ * Backend cipher definitions available to DRBG
+ ***************************************************************/
+
+const struct drbg_core cores[] = {
+ /* Hash DRBGs */
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+ {
+ .flags = DRBG_HASH | DRBG_STRENGTH128,
+ .statelen = 55, /* 440 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 20,
+ .cra_name = "sha1",
+ .cra_driver_name = "sha1",
+ .backend_cra_name = "sha1",
+ }, {
+ .flags = DRBG_HASH | DRBG_STRENGTH256,
+ .statelen = 55, /* 440 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 32,
+ .cra_name = "sha256",
+ .cra_driver_name = "sha256",
+ .backend_cra_name = "sha256",
+ }, {
+ .flags = DRBG_HASH | DRBG_STRENGTH256,
+ .statelen = 111, /* 888 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 48,
+ .cra_name = "sha384",
+ .cra_driver_name = "sha384",
+ .backend_cra_name = "sha384",
+ }, {
+ .flags = DRBG_HASH | DRBG_STRENGTH256,
+ .statelen = 111, /* 888 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 64,
+ .cra_name = "sha512",
+ .cra_driver_name = "sha512",
+ .backend_cra_name = "sha512",
+ },
+#endif /* CONFIG_CRYPTO_DRBG_HASH */
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+ {
+ /* HMAC DRBGs */
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 20, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 20,
+ .cra_name = "hmac(sha1)",
+ .cra_driver_name = "hmac_sha1",
+ .backend_cra_name = "hmac(sha1)",
+ }, {
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 32, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 32,
+ .cra_name = "hmac(sha256)",
+ .cra_driver_name = "hmac_sha256",
+ .backend_cra_name = "hmac(sha256)",
+ }, {
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 48, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 48,
+ .cra_name = "hmac(sha384)",
+ .cra_driver_name = "hmac_sha384",
+ .backend_cra_name = "hmac(sha384)",
+ }, {
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 64, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 64,
+ .cra_name = "hmac(sha512)",
+ .cra_driver_name = "hmac_sha512",
+ .backend_cra_name = "hmac(sha512)",
+ },
+#endif /* CONFIG_CRYPTO_DRBG_HMAC */
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+ {
+ /* block ciphers */
+ .flags = DRBG_CTR | DRBG_STRENGTH128,
+ .statelen = 32, /* 256 bits as defined in 10.2.1 */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 16,
+ .cra_name = "ctr(aes128)",
+ .cra_driver_name = "ctr_aes128",
+ .backend_cra_name = "ecb(aes)",
+ }, {
+ /* block ciphers */
+ .flags = DRBG_CTR | DRBG_STRENGTH192,
+ .statelen = 40, /* 320 bits as defined in 10.2.1 */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 16,
+ .cra_name = "ctr(aes192)",
+ .cra_driver_name = "ctr_aes192",
+ .backend_cra_name = "ecb(aes)",
+ }, {
+ /* block ciphers */
+ .flags = DRBG_CTR | DRBG_STRENGTH256,
+ .statelen = 48, /* 384 bits as defined in 10.2.1 */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 16,
+ .cra_name = "ctr(aes256)",
+ .cra_driver_name = "ctr_aes256",
+ .backend_cra_name = "ecb(aes)",
+ },
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+};
+
+/******************************************************************
+ * Generic helper functions
+ ******************************************************************/
+
+/*
+ * Return strength of DRBG according to SP800-90A section 8.4
+ *
+ * @flags DRBG flags reference
+ *
+ * Return: normalized strength in *bytes* value or 32 as default
+ * to counter programming errors
+ */
+static inline unsigned short drbg_sec_strength(drbg_flag_t flags)
+{
+ switch (flags & DRBG_STRENGTH_MASK) {
+ case DRBG_STRENGTH128:
+ return 16;
+ case DRBG_STRENGTH192:
+ return 24;
+ case DRBG_STRENGTH256:
+ return 32;
+ default:
+ return 32;
+ }
+}
+
+/*
+ * FIPS 140-2 continuous self test
+ * The test is performed on the result of one round of the output
+ * function. Thus, the function implicitly knows the size of the
+ * buffer.
+ *
+ * The FIPS test can be called in an endless loop until it returns
+ * true. Although the code looks like a potential for a deadlock, it
+ * is not the case, because returning a false cannot mathematically
+ * occur (except once when a reseed took place and the updated state
+ * would is now set up such that the generation of new value returns
+ * an identical one -- this is most unlikely and would happen only once).
+ * Thus, if this function repeatedly returns false and thus would cause
+ * a deadlock, the integrity of the entire kernel is lost.
+ *
+ * @drbg DRBG handle
+ * @buf output buffer of random data to be checked
+ *
+ * return:
+ * true on success
+ * false on error
+ */
+static bool drbg_fips_continuous_test(struct drbg_state *drbg,
+ unsigned char *buf)
+{
+#ifdef CONFIG_CRYPTO_FIPS
+ int ret = 0;
+ /* skip test if we test the overall system */
+ if (drbg->test_data)
+ return true;
+ /* only perform test in FIPS mode */
+ if (0 == fips_enabled)
+ return true;
+ if (!drbg->fips_primed) {
+ /* Priming of FIPS test */
+ memcpy(drbg->prev, buf, drbg_blocklen(drbg));
+ drbg->fips_primed = true;
+ /* return false due to priming, i.e. another round is needed */
+ return false;
+ }
+ ret = memcmp(drbg->prev, buf, drbg_blocklen(drbg));
+ memcpy(drbg->prev, buf, drbg_blocklen(drbg));
+ /* the test shall pass when the two compared values are not equal */
+ return ret != 0;
+#else
+ return true;
+#endif /* CONFIG_CRYPTO_FIPS */
+}
+
+/*
+ * Convert an integer into a byte representation of this integer.
+ * The byte representation is big-endian
+ *
+ * @buf buffer holding the converted integer
+ * @val value to be converted
+ * @buflen length of buffer
+ */
+#if (defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_CTR))
+static inline void drbg_int2byte(unsigned char *buf, uint64_t val,
+ size_t buflen)
+{
+ unsigned char *byte;
+ uint64_t i;
+
+ byte = buf + (buflen - 1);
+ for (i = 0; i < buflen; i++)
+ *(byte--) = val >> (i * 8) & 0xff;
+}
+
+/*
+ * Increment buffer
+ *
+ * @dst buffer to increment
+ * @add value to add
+ */
+static inline void drbg_add_buf(unsigned char *dst, size_t dstlen,
+ unsigned char *add, size_t addlen)
+{
+ /* implied: dstlen > addlen */
+ unsigned char *dstptr, *addptr;
+ unsigned int remainder = 0;
+ size_t len = addlen;
+
+ dstptr = dst + (dstlen-1);
+ addptr = add + (addlen-1);
+ while (len) {
+ remainder += *dstptr + *addptr;
+ *dstptr = remainder & 0xff;
+ remainder >>= 8;
+ len--; dstptr--; addptr--;
+ }
+ len = dstlen - addlen;
+ while (len && remainder > 0) {
+ remainder = *dstptr + 1;
+ *dstptr = remainder & 0xff;
+ remainder >>= 8;
+ len--; dstptr--;
+ }
+}
+#endif /* defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_CTR) */
+
+/******************************************************************
+ * CTR DRBG callback functions
+ ******************************************************************/
+
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+static int drbg_kcapi_sym(struct drbg_state *drbg, unsigned char *key,
+ unsigned char *outval, struct drbg_string *in);
+static int drbg_init_sym_kernel(struct drbg_state *drbg);
+static int drbg_fini_sym_kernel(struct drbg_state *drbg);
+
+/* BCC function for CTR DRBG as defined in 10.4.3 */
+static int drbg_ctr_bcc(struct drbg_state *drbg,
+ unsigned char *out, unsigned char *key,
+ struct drbg_string *in)
+{
+ int ret = -EFAULT;
+ struct drbg_string *curr = in;
+ size_t inpos = curr->len;
+ const unsigned char *pos = curr->buf;
+ struct drbg_string data;
+
+ drbg_string_fill(&data, out, drbg_blocklen(drbg));
+
+ /* 10.4.3 step 1 */
+ memset(out, 0, drbg_blocklen(drbg));
+
+ /* 10.4.3 step 2 / 4 */
+ while (inpos) {
+ short cnt = 0;
+ /* 10.4.3 step 4.1 */
+ for (cnt = 0; cnt < drbg_blocklen(drbg); cnt++) {
+ out[cnt] ^= *pos;
+ pos++; inpos--;
+ /* the following branch implements the linked list
+ * iteration. If we are at the end of the current data
+ * set, we have to start using the next data set if
+ * available -- the inpos value always points to the
+ * current byte and will be zero if we have processed
+ * the last byte of the last linked list member */
+ if (0 == inpos) {
+ curr = curr->next;
+ if (NULL != curr) {
+ pos = curr->buf;
+ inpos = curr->len;
+ } else {
+ inpos = 0;
+ break;
+ }
+ }
+ }
+ /* 10.4.3 step 4.2 */
+ ret = drbg_kcapi_sym(drbg, key, out, &data);
+ if (ret)
+ return ret;
+ /* 10.4.3 step 2 */
+ }
+ return 0;
+}
+
+/*
+ * scratchpad usage: drbg_ctr_update is interlinked with drbg_ctr_df
+ * (and drbg_ctr_bcc, but this function does not need any temporary buffers),
+ * the scratchpad is used as follows:
+ * drbg_ctr_update:
+ * temp
+ * start: drbg->scratchpad
+ * length: drbg_statelen(drbg) + drbg_blocklen(drbg)
+ * note: the cipher writing into this variable works
+ * blocklen-wise. Now, when the statelen is not a multiple
+ * of blocklen, the generateion loop below "spills over"
+ * by at most blocklen. Thus, we need to give sufficient
+ * memory.
+ * df_data
+ * start: drbg->scratchpad +
+ * drbg_statelen(drbg) + drbg_blocklen(drbg)
+ * length: drbg_statelen(drbg)
+ *
+ * drbg_ctr_df:
+ * pad
+ * start: df_data + drbg_statelen(drbg)
+ * length: drbg_blocklen(drbg)
+ * iv
+ * start: pad + drbg_blocklen(drbg)
+ * length: drbg_blocklen(drbg)
+ * temp
+ * start: iv + drbg_blocklen(drbg)
+ * length: (drbg_keylen(drbg) + drbg_blocklen(drbg) ==
+ * drbg_statelen(drbg))
+ */
+
+/* Derivation Function for CTR DRBG as defined in 10.4.2 */
+static int drbg_ctr_df(struct drbg_state *drbg,
+ unsigned char *df_data, size_t bytes_to_return,
+ struct drbg_string *addtl)
+{
+ int ret = -EFAULT;
+ unsigned char L_N[8];
+ /* S3 is input */
+ struct drbg_string S1, S2, S4, cipherin;
+ struct drbg_string *tempstr = addtl;
+ unsigned char *pad = df_data + drbg_statelen(drbg);
+ unsigned char *iv = pad + drbg_blocklen(drbg);
+ unsigned char *temp = iv + drbg_blocklen(drbg);
+ size_t padlen = 0;
+ unsigned int templen = 0;
+ /* 10.4.2 step 7 */
+ unsigned int i = 0;
+ /* 10.4.2 step 8 */
+ unsigned char *K = (unsigned char *)
+ "\x00\x01\x02\x03\x04\x05\x06\x07"
+ "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f"
+ "\x10\x11\x12\x13\x14\x15\x16\x17"
+ "\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f";
+ unsigned char *X;
+ size_t generated_len = 0;
+ size_t inputlen = 0;
+
+ memset(pad, 0, drbg_blocklen(drbg));
+ memset(iv, 0, drbg_blocklen(drbg));
+ memset(temp, 0, drbg_statelen(drbg));
+
+ /* 10.4.2 step 1 is implicit as we work byte-wise */
+
+ /* 10.4.2 step 2 */
+ if ((512/8) < bytes_to_return)
+ return -EINVAL;
+
+ /* 10.4.2 step 2 -- calculate the entire length of all input data */
+ for (; NULL != tempstr; tempstr = tempstr->next)
+ inputlen += tempstr->len;
+ drbg_int2byte(&L_N[0], inputlen, 4);
+
+ /* 10.4.2 step 3 */
+ drbg_int2byte(&L_N[4], bytes_to_return, 4);
+
+ /* 10.4.2 step 5: length is L_N, input_string, one byte, padding */
+ padlen = (inputlen + sizeof(L_N) + 1) % (drbg_blocklen(drbg));
+ /* wrap the padlen appropriately */
+ if (padlen)
+ padlen = drbg_blocklen(drbg) - padlen;
+ /* pad / padlen contains the 0x80 byte and the following zero bytes, so
+ * add one for byte for 0x80 */
+ padlen++;
+ pad[0] = 0x80;
+
+ /* 10.4.2 step 4 -- first fill the linked list and then order it */
+ drbg_string_fill(&S1, iv, drbg_blocklen(drbg));
+ drbg_string_fill(&S2, L_N, sizeof(L_N));
+ drbg_string_fill(&S4, pad, padlen);
+ S1.next = &S2;
+ S2.next = addtl;
+ /* splice in addtl between S2 and S4 -- we place S4 at the end of the
+ * input data chain */
+ tempstr = addtl;
+ for (; NULL != tempstr; tempstr = tempstr->next)
+ if (NULL == tempstr->next)
+ break;
+ tempstr->next = &S4;
+
+ /* 10.4.2 step 9 */
+ while (templen < (drbg_keylen(drbg) + (drbg_blocklen(drbg)))) {
+ /* 10.4.2 step 9.1 - the padding is implicit as the buffer
+ * holds zeros after allocation -- even the increment of i
+ * is irrelevant as the increment remains within length of i */
+ drbg_int2byte(iv, i, 4);
+ /* 10.4.2 step 9.2 -- BCC and concatenation with temp */
+ ret = drbg_ctr_bcc(drbg, temp + templen, K, &S1);
+ if (ret)
+ goto out;
+ /* 10.4.2 step 9.3 */
+ i++;
+ templen += drbg_blocklen(drbg);
+ }
+
+ /* 10.4.2 step 11 */
+ /* implicit key len with seedlen - blocklen according to table 3 */
+ X = temp + (drbg_keylen(drbg));
+ drbg_string_fill(&cipherin, X, drbg_blocklen(drbg));
+
+ /* 10.4.2 step 12: overwriting of outval */
+
+ /* 10.4.2 step 13 */
+ while (generated_len < bytes_to_return) {
+ short blocklen = 0;
+ /* 10.4.2 step 13.1 */
+ /* the truncation of the key length is implicit as the key
+ * is only drbg_blocklen in size -- check for the implementation
+ * of the cipher function callback */
+ ret = drbg_kcapi_sym(drbg, temp, X, &cipherin);
+ if (ret)
+ goto out;
+ blocklen = (drbg_blocklen(drbg) <
+ (bytes_to_return - generated_len)) ?
+ drbg_blocklen(drbg) :
+ (bytes_to_return - generated_len);
+ /* 10.4.2 step 13.2 and 14 */
+ memcpy(df_data + generated_len, X, blocklen);
+ generated_len += blocklen;
+ }
+
+ ret = 0;
+
+out:
+ memset(iv, 0, drbg_blocklen(drbg));
+ memset(temp, 0, drbg_statelen(drbg));
+ memset(pad, 0, drbg_blocklen(drbg));
+ return ret;
+}
+
+/* update function of CTR DRBG as defined in 10.2.1.2 */
+static int drbg_ctr_update(struct drbg_state *drbg,
+ struct drbg_string *addtl, int reseed)
+{
+ int ret = -EFAULT;
+ /* 10.2.1.2 step 1 */
+ unsigned char *temp = drbg->scratchpad;
+ unsigned char *df_data = drbg->scratchpad + drbg_statelen(drbg) +
+ drbg_blocklen(drbg);
+ unsigned char *temp_p, *df_data_p; /* pointer to iterate over buffers */
+ unsigned int len = 0;
+ struct drbg_string cipherin;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ memset(temp, 0, drbg_statelen(drbg) + drbg_blocklen(drbg));
+ memset(df_data, 0, drbg_statelen(drbg));
+
+ /* 10.2.1.3.2 step 2 and 10.2.1.4.2 step 2 */
+ if (addtl && 0 < addtl->len) {
+ ret = drbg_ctr_df(drbg, df_data, drbg_statelen(drbg),
+ addtl);
+ if (ret)
+ goto out;
+ }
+
+ drbg_string_fill(&cipherin, drbg->V, drbg_blocklen(drbg));
+ /* 10.2.1.3.2 step 2 and 3 -- are already covered as we memset(0)
+ * all memory during initialization */
+ while (len < (drbg_statelen(drbg))) {
+ /* 10.2.1.2 step 2.1 */
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ /* 10.2.1.2 step 2.2 */
+ /* using target of temp + len: 10.2.1.2 step 2.3 and 3 */
+ ret = drbg_kcapi_sym(drbg, drbg->C, temp + len, &cipherin);
+ if (ret)
+ goto out;
+ /* 10.2.1.2 step 2.3 and 3 */
+ len += drbg_blocklen(drbg);
+ }
+
+ /* 10.2.1.2 step 4 */
+ temp_p = temp;
+ df_data_p = df_data;
+ for (len = 0; len < drbg_statelen(drbg); len++) {
+ *temp_p ^= *df_data_p;
+ df_data_p++; temp_p++;
+ }
+
+ /* 10.2.1.2 step 5 */
+ memcpy(drbg->C, temp, drbg_keylen(drbg));
+ /* 10.2.1.2 step 6 */
+ memcpy(drbg->V, temp + drbg_keylen(drbg), drbg_blocklen(drbg));
+ ret = 0;
+
+out:
+ memset(temp, 0, drbg_statelen(drbg) + drbg_blocklen(drbg));
+ memset(df_data, 0, drbg_statelen(drbg));
+ return ret;
+}
+
+/*
+ * scratchpad use: drbg_ctr_update is called independently from
+ * drbg_ctr_extract_bytes. Therefore, the scratchpad is reused
+ */
+/* Generate function of CTR DRBG as defined in 10.2.1.5.2 */
+static unsigned int drbg_ctr_generate(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ unsigned int len = 0;
+ struct drbg_string data;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+
+ /* 10.2.1.5.2 step 2 */
+ if (addtl && 0 < addtl->len) {
+ addtl->next = NULL;
+ if (drbg_ctr_update(drbg, addtl, 1))
+ return 0;
+ }
+
+ /* 10.2.1.5.2 step 4.1 */
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ drbg_string_fill(&data, drbg->V, drbg_blocklen(drbg));
+ while (len < buflen) {
+ unsigned int outlen = 0;
+ /* 10.2.1.5.2 step 4.2 */
+ if (drbg_kcapi_sym(drbg, drbg->C, drbg->scratchpad, &data)) {
+ len = 0;
+ goto out;
+ }
+ outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
+ drbg_blocklen(drbg) : (buflen - len);
+ if (!drbg_fips_continuous_test(drbg, drbg->scratchpad)) {
+ /* 10.2.1.5.2 step 6 */
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ continue;
+ }
+ /* 10.2.1.5.2 step 4.3 */
+ memcpy(buf + len, drbg->scratchpad, outlen);
+ len += outlen;
+ /* 10.2.1.5.2 step 6 */
+ if (len < buflen)
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ }
+
+ /* 10.2.1.5.2 step 6 */
+ /*TODO the DF function is called again since according to step
+ * 2, the "additional_input" after step 2 is the output of the DF
+ * function -- when we save the DF output as a replacement
+ * for the addtl_input data, we do not need to call the DF again here */
+ if (addtl)
+ addtl->next = NULL;
+ if (drbg_ctr_update(drbg, addtl, 1))
+ return 0;
+
+out:
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ return len;
+}
+
+static struct drbg_state_ops drbg_ctr_ops = {
+ .update = drbg_ctr_update,
+ .generate = drbg_ctr_generate,
+ .crypto_init = drbg_init_sym_kernel,
+ .crypto_fini = drbg_fini_sym_kernel,
+};
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+
+/******************************************************************
+ * HMAC DRBG callback functions
+ ******************************************************************/
+
+#if defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_HMAC)
+static int drbg_kcapi_hash(struct drbg_state *drbg, unsigned char *key,
+ unsigned char *outval, struct drbg_string *in);
+static int drbg_init_hash_kernel(struct drbg_state *drbg);
+static int drbg_fini_hash_kernel(struct drbg_state *drbg);
+#endif /* (CONFIG_CRYPTO_DRBG_HASH || CONFIG_CRYPTO_DRBG_HMAC) */
+
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+/* update function of HMAC DRBG as defined in 10.1.2.2 */
+static int drbg_hmac_update(struct drbg_state *drbg, struct drbg_string *seed,
+ int reseed)
+{
+ int ret = -EFAULT;
+ int i = 0;
+ struct drbg_string seed1, seed2, cipherin;
+
+ if (!reseed) {
+ /* 10.1.2.3 step 2 already implicitly covered with
+ * the initial memset(0) of drbg->C */
+ memset(drbg->C, 0, drbg_statelen(drbg));
+ memset(drbg->V, 1, drbg_statelen(drbg));
+ }
+
+ /* build linked list which implements the concatenation and fill
+ * first part*/
+ drbg_string_fill(&seed1, drbg->V, drbg_statelen(drbg));
+ /* buffer will be filled in for loop below with one byte */
+ drbg_string_fill(&seed2, NULL, 1);
+ seed1.next = &seed2;
+ /* seed may be NULL */
+ seed2.next = seed;
+
+ drbg_string_fill(&cipherin, drbg->V, drbg_statelen(drbg));
+ /* we execute two rounds of V/K massaging */
+ for (i = 2; 0 < i; i--) {
+ /* first round uses 0x0, second 0x1 */
+ unsigned char prefix = DRBG_PREFIX0;
+ if (1 == i)
+ prefix = DRBG_PREFIX1;
+ /* 10.1.2.2 step 1 and 4 -- concatenation and HMAC for key */
+ seed2.buf = &prefix;
+ ret = drbg_kcapi_hash(drbg, drbg->C, drbg->C, &seed1);
+ if (ret)
+ return ret;
+
+ /* 10.1.2.2 step 2 and 5 -- HMAC for V */
+ ret = drbg_kcapi_hash(drbg, drbg->C, drbg->V, &cipherin);
+ if (ret)
+ return ret;
+
+ /* 10.1.2.2 step 3 */
+ if (!seed || 0 == seed->len)
+ return ret;
+ }
+
+ return 0;
+}
+
+/* generate function of HMAC DRBG as defined in 10.1.2.5 */
+static unsigned int drbg_hmac_generate(struct drbg_state *drbg,
+ unsigned char *buf,
+ unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ unsigned int len = 0;
+ struct drbg_string data;
+
+ /* 10.1.2.5 step 2 */
+ if (addtl && 0 < addtl->len) {
+ addtl->next = NULL;
+ if (drbg_hmac_update(drbg, addtl, 1))
+ return 0;
+ }
+
+ drbg_string_fill(&data, drbg->V, drbg_statelen(drbg));
+ while (len < buflen) {
+ unsigned int outlen = 0;
+ /* 10.1.2.5 step 4.1 */
+ if (drbg_kcapi_hash(drbg, drbg->C, drbg->V, &data))
+ return 0;
+ outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
+ drbg_blocklen(drbg) : (buflen - len);
+ if (!drbg_fips_continuous_test(drbg, drbg->V))
+ continue;
+
+ /* 10.1.2.5 step 4.2 */
+ memcpy(buf + len, drbg->V, outlen);
+ len += outlen;
+ }
+
+ /* 10.1.2.5 step 6 */
+ if (addtl)
+ addtl->next = NULL;
+ if (drbg_hmac_update(drbg, addtl, 1))
+ return 0;
+
+ return len;
+}
+
+static struct drbg_state_ops drbg_hmac_ops = {
+ .update = drbg_hmac_update,
+ .generate = drbg_hmac_generate,
+ .crypto_init = drbg_init_hash_kernel,
+ .crypto_fini = drbg_fini_hash_kernel,
+
+};
+#endif /* CONFIG_CRYPTO_DRBG_HMAC */
+
+/******************************************************************
+ * Hash DRBG callback functions
+ ******************************************************************/
+
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+/*
+ * scratchpad usage: as drbg_hash_update and drbg_hash_df are used
+ * interlinked, the scratchpad is used as follows:
+ * drbg_hash_update
+ * start: drbg->scratchpad
+ * length: drbg_statelen(drbg)
+ * drbg_hash_df:
+ * start: drbg->scratchpad + drbg_statelen(drbg)
+ * length: drbg_blocklen(drbg)
+ */
+/* Derivation Function for Hash DRBG as defined in 10.4.1 */
+static int drbg_hash_df(struct drbg_state *drbg,
+ unsigned char *outval, size_t outlen,
+ struct drbg_string *entropy)
+{
+ int ret = 0;
+ size_t len = 0;
+ unsigned char input[5];
+ unsigned char *tmp = drbg->scratchpad + drbg_statelen(drbg);
+ struct drbg_string data1;
+
+ memset(tmp, 0, drbg_blocklen(drbg));
+
+ /* 10.4.1 step 3 */
+ input[0] = 1;
+ drbg_int2byte(&input[1], (outlen * 8), 4);
+
+ /* 10.4.1 step 4.1 -- concatenation of data for input into hash */
+ drbg_string_fill(&data1, input, 5);
+ data1.next = entropy;
+
+ /* 10.4.1 step 4 */
+ while (len < outlen) {
+ short blocklen = 0;
+ /* 10.4.1 step 4.1 */
+ ret = drbg_kcapi_hash(drbg, NULL, tmp, &data1);
+ if (ret)
+ goto out;
+ /* 10.4.1 step 4.2 */
+ input[0]++;
+ blocklen = (drbg_blocklen(drbg) < (outlen - len)) ?
+ drbg_blocklen(drbg) : (outlen - len);
+ memcpy(outval + len, tmp, blocklen);
+ len += blocklen;
+ }
+
+out:
+ memset(tmp, 0, drbg_blocklen(drbg));
+ return ret;
+}
+
+/* update function for Hash DRBG as defined in 10.1.1.2 / 10.1.1.3 */
+static int drbg_hash_update(struct drbg_state *drbg, struct drbg_string *seed,
+ int reseed)
+{
+ int ret = 0;
+ struct drbg_string data1, data2;
+ unsigned char *V = drbg->scratchpad;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ memset(drbg->scratchpad, 0, drbg_statelen(drbg));
+ if (!seed)
+ return -EINVAL;
+
+ if (reseed) {
+ /* 10.1.1.3 step 1: string length is concatenation of
+ * 1 byte, V and seed (which is concatenated entropy/addtl
+ * input)
+ */
+ memcpy(V, drbg->V, drbg_statelen(drbg));
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, V, drbg_statelen(drbg));
+ data1.next = &data2;
+ data2.next = seed;
+ } else {
+ drbg_string_fill(&data1, seed->buf, seed->len);
+ data1.next = seed->next;
+ }
+
+ /* 10.1.1.2 / 10.1.1.3 step 2 and 3 */
+ ret = drbg_hash_df(drbg, drbg->V, drbg_statelen(drbg), &data1);
+ if (ret)
+ goto out;
+
+ /* 10.1.1.2 / 10.1.1.3 step 4 -- concatenation */
+ prefix = DRBG_PREFIX0;
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, drbg->V, drbg_statelen(drbg));
+ data1.next = &data2;
+ /* 10.1.1.2 / 10.1.1.3 step 4 -- df operation */
+ ret = drbg_hash_df(drbg, drbg->C, drbg_statelen(drbg), &data1);
+
+out:
+ memset(drbg->scratchpad, 0, drbg_statelen(drbg));
+ return ret;
+}
+
+/* processing of additional information string for Hash DRBG */
+static int drbg_hash_process_addtl(struct drbg_state *drbg,
+ struct drbg_string *addtl)
+{
+ int ret = 0;
+ struct drbg_string data1, data2;
+ struct drbg_string *data3;
+ unsigned char prefix = DRBG_PREFIX2;
+
+ /* this is value w as per documentation */
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+
+ /* 10.1.1.4 step 2 */
+ if (!addtl || 0 == addtl->len)
+ return 0;
+
+ /* 10.1.1.4 step 2a -- concatenation */
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, drbg->V, drbg_statelen(drbg));
+ data3 = addtl;
+ data1.next = &data2;
+ data2.next = data3;
+ data3->next = NULL;
+ /* 10.1.1.4 step 2a -- cipher invocation */
+ ret = drbg_kcapi_hash(drbg, NULL, drbg->scratchpad, &data1);
+ if (ret)
+ goto out;
+
+ /* 10.1.1.4 step 2b */
+ drbg_add_buf(drbg->V, drbg_statelen(drbg),
+ drbg->scratchpad, drbg_blocklen(drbg));
+
+out:
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ return ret;
+}
+
+/*
+ * Hashgen defined in 10.1.1.4
+ */
+static unsigned int drbg_hash_hashgen(struct drbg_state *drbg,
+ unsigned char *buf,
+ unsigned int buflen)
+{
+ unsigned int len = 0;
+ unsigned char *src = drbg->scratchpad;
+ unsigned char *dst = drbg->scratchpad + drbg_statelen(drbg);
+ struct drbg_string data;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ /* use the scratchpad as a lookaside buffer */
+ memset(src, 0, drbg_statelen(drbg));
+ memset(dst, 0, drbg_blocklen(drbg));
+
+ /* 10.1.1.4 step hashgen 2 */
+ memcpy(src, drbg->V, drbg_statelen(drbg));
+
+ drbg_string_fill(&data, src, drbg_statelen(drbg));
+ while (len < buflen) {
+ unsigned int outlen = 0;
+ /* 10.1.1.4 step hashgen 4.1 */
+ if (drbg_kcapi_hash(drbg, NULL, dst, &data)) {
+ len = 0;
+ goto out;
+ }
+ outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
+ drbg_blocklen(drbg) : (buflen - len);
+ if (!drbg_fips_continuous_test(drbg, dst)) {
+ drbg_add_buf(src, drbg_statelen(drbg), &prefix, 1);
+ continue;
+ }
+ /* 10.1.1.4 step hashgen 4.2 */
+ memcpy(buf + len, dst, outlen);
+ len += outlen;
+ /* 10.1.1.4 hashgen step 4.3 */
+ if (len < buflen)
+ drbg_add_buf(src, drbg_statelen(drbg), &prefix, 1);
+ }
+
+out:
+ memset(drbg->scratchpad, 0,
+ (drbg_statelen(drbg) + drbg_blocklen(drbg)));
+ return len;
+}
+
+/* generate function for Hash DRBG as defined in 10.1.1.4 */
+static unsigned int drbg_hash_generate(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ unsigned int len = 0;
+ unsigned char req[8];
+ unsigned char prefix = DRBG_PREFIX3;
+ struct drbg_string data1, data2;
+
+ /*
+ * scratchpad usage: drbg_hash_process_addtl uses the scratchpad, but
+ * fully completes before returning. Thus, we can reuse the scratchpad
+ */
+ /* 10.1.1.4 step 2 */
+ if (drbg_hash_process_addtl(drbg, addtl))
+ return 0;
+ /* 10.1.1.4 step 3 -- invocation of the Hashgen function defined in
+ * 10.1.1.4 */
+ len = drbg_hash_hashgen(drbg, buf, buflen);
+
+ /* this is the value H as documented in 10.1.1.4 */
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ /* 10.1.1.4 step 4 */
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, drbg->V, drbg_statelen(drbg));
+ data1.next = &data2;
+ if (drbg_kcapi_hash(drbg, NULL, drbg->scratchpad, &data1)) {
+ len = 0;
+ goto out;
+ }
+
+ /* 10.1.1.4 step 5 */
+ drbg_add_buf(drbg->V, drbg_statelen(drbg),
+ drbg->scratchpad, drbg_blocklen(drbg));
+ drbg_add_buf(drbg->V, drbg_statelen(drbg),
+ drbg->C, drbg_statelen(drbg));
+ drbg_int2byte(req, drbg->reseed_ctr, sizeof(req));
+ drbg_add_buf(drbg->V, drbg_statelen(drbg), req, 8);
+
+out:
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ return len;
+}
+
+/*
+ * scratchpad usage: as update and generate are used isolated, both
+ * can use the scratchpad
+ */
+static struct drbg_state_ops drbg_hash_ops = {
+ .update = drbg_hash_update,
+ .generate = drbg_hash_generate,
+ .crypto_init = drbg_init_hash_kernel,
+ .crypto_fini = drbg_fini_hash_kernel,
+};
+#endif /* CONFIG_CRYPTO_DRBG_HASH */
+
+/******************************************************************
+ * Functions common for DRBG implementations
+ ******************************************************************/
+
+/*
+ * Seeding or reseeding of the DRBG
+ *
+ * @drbg: DRBG state struct
+ * @pers: personalization / additional information buffer
+ * @reseed: 0 for initial seed process, 1 for reseeding
+ *
+ * return:
+ * 0 on success
+ * error value otherwise
+ */
+static int drbg_seed(struct drbg_state *drbg, struct drbg_string *pers,
+ bool reseed)
+{
+ int ret = 0;
+ unsigned char *entropy = NULL;
+ size_t entropylen = 0;
+ struct drbg_string data1;
+ struct drbg_string *data2;
+
+ /* 9.1 / 9.2 / 9.3.1 step 3 */
+ if (pers && pers->len > (drbg_max_addtl(drbg))) {
+ pr_devel("DRBG: personalization string too long %lu\n",
+ pers->len);
+ return -EINVAL;
+ }
+
+ if (drbg->test_data && drbg->test_data->testentropy) {
+ drbg_string_fill(&data1, drbg->test_data->testentropy->buf,
+ drbg->test_data->testentropy->len);
+ pr_devel("DRBG: using test entropy\n");
+ } else {
+ /* Gather entropy equal to the security strength of the DRBG.
+ * With a derivation function, a nonce is required in addition
+ * to the entropy. A nonce must be at least 1/2 of the security
+ * strength of the DRBG in size. Thus, entropy * nonce is 3/2
+ * of the strength. The consideration of a nonce is only
+ * applicable during initial seeding. */
+ entropylen = drbg_sec_strength(drbg->core->flags);
+ if (!entropylen)
+ return -EFAULT;
+ if (!reseed)
+ /* make sure we round up strength/2 in
+ * case it is not divisible by 2 */
+ entropylen = ((entropylen + 1) / 2) * 3;
+ pr_devel("DRBG: (re)seeding with %zu bytes of entropy\n",
+ entropylen);
+ entropy = kzalloc(entropylen, GFP_KERNEL);
+ if (!entropy)
+ return -ENOMEM;
+ get_random_bytes(entropy, entropylen);
+ drbg_string_fill(&data1, entropy, entropylen);
+ }
+
+ /* concatenation of entropy with personalization str / addtl input) */
+ if (pers && 0 < pers->len) {
+ data2 = pers;
+ data2->next = NULL;
+ data1.next = data2;
+ pr_devel("DRBG: using personalization string\n");
+ }
+
+ ret = drbg->d_ops->update(drbg, &data1, reseed);
+ if (ret)
+ goto out;
+
+ drbg->seeded = true;
+ /* 10.1.1.2 / 10.1.1.3 step 5 */
+ drbg->reseed_ctr = 1;
+
+out:
+ if (entropy)
+ kzfree(entropy);
+ return ret;
+}
+
+/*
+ * Free all substructures in a DRBG state without the DRBG state structure
+ */
+static inline void drbg_dealloc_state(struct drbg_state *drbg)
+{
+ if (!drbg)
+ return;
+ if (drbg->V)
+ kzfree(drbg->V);
+ drbg->V = NULL;
+ if (drbg->C)
+ kzfree(drbg->C);
+ drbg->C = NULL;
+ if (drbg->scratchpad)
+ kzfree(drbg->scratchpad);
+ drbg->scratchpad = NULL;
+ drbg->reseed_ctr = 0;
+#ifdef CONFIG_CRYPTO_FIPS
+ if (drbg->prev)
+ kzfree(drbg->prev);
+ drbg->prev = NULL;
+ drbg->fips_primed = false;
+#endif
+}
+
+/*
+ * Allocate all sub-structures for a DRBG state
+ * The DRBG state structure must already be allocated
+ */
+static inline int drbg_alloc_state(struct drbg_state *drbg)
+{
+ int ret = -ENOMEM;
+ unsigned int sb_size = 0;
+
+ if (!drbg)
+ return -EINVAL;
+
+ drbg->V = kzalloc(drbg_statelen(drbg), GFP_KERNEL);
+ if (!drbg->V)
+ goto err;
+ drbg->C = kzalloc(drbg_statelen(drbg), GFP_KERNEL);
+ if (!drbg->C)
+ goto err;
+#ifdef CONFIG_CRYPTO_FIPS
+ drbg->prev = kzalloc(drbg_blocklen(drbg), GFP_KERNEL);
+ if (!drbg->prev)
+ goto err;
+ drbg->fips_primed = false;
+#endif
+ /* scratchpad is only generated for CTR and Hash */
+ if (drbg->core->flags & DRBG_HMAC)
+ sb_size = 0;
+ else if (drbg->core->flags & DRBG_CTR)
+ sb_size = drbg_statelen(drbg) + drbg_blocklen(drbg) + /* temp */
+ drbg_statelen(drbg) + /* df_data */
+ drbg_blocklen(drbg) + /* pad */
+ drbg_blocklen(drbg) + /* iv */
+ drbg_statelen(drbg); /* temp */
+ else
+ sb_size = drbg_statelen(drbg) + drbg_blocklen(drbg);
+
+ if (0 < sb_size) {
+ drbg->scratchpad = kzalloc(sb_size, GFP_KERNEL);
+ if (!drbg->scratchpad)
+ goto err;
+ }
+ spin_lock_init(&drbg->drbg_lock);
+ return 0;
+
+err:
+ drbg_dealloc_state(drbg);
+ return ret;
+}
+
+/*
+ * Strategy to avoid holding long term locks: generate a shadow copy of DRBG
+ * and perform all operations on this shadow copy. After finishing, restore
+ * the updated state of the shadow copy into original drbg state. This way,
+ * only the read and write operations of the original drbg state must be
+ * locked
+ */
+
+/*
+ * Copy the DRBG state
+ */
+static inline void drbg_copy_drbg(struct drbg_state *src,
+ struct drbg_state *dst)
+{
+ if (!src || !dst)
+ return;
+ memcpy(dst->V, src->V, drbg_statelen(src));
+ memcpy(dst->C, src->C, drbg_statelen(src));
+ dst->reseed_ctr = src->reseed_ctr;
+ /* no copy of scratchpad */
+ /* priv_data is initialized with call to crypto_init */
+ /* d_ops are set outside, as the struct is const */
+ dst->seeded = src->seeded;
+ dst->pr = src->pr;
+#ifdef CONFIG_CRYPTO_FIPS
+ dst->fips_primed = src->fips_primed;
+ memcpy(dst->prev, src->prev, drbg_blocklen(src));
+#endif
+ /* test_data is set outside, as the struct is const */
+}
+/*
+ * Generate shadow copy of the DRBG state
+ */
+static int drbg_make_shadow(struct drbg_state *drbg, struct drbg_state **shadow)
+{
+ int ret = -ENOMEM;
+ struct drbg_state *tmp = NULL;
+
+ /* some sanity checks */
+ if (!drbg || !drbg->core || !drbg->V || !drbg->C) {
+ pr_devel("DRBG: attempt to generate shadow copy for "
+ "uninitialized DRBG state rejected\n");
+ return -EINVAL;
+ }
+ /* HMAC does not have a scratchpad */
+ if (!(drbg->core->flags & DRBG_HMAC) && NULL == drbg->scratchpad)
+ return -EINVAL;
+
+ tmp = kzalloc(sizeof(struct drbg_state), GFP_KERNEL);
+ if (!tmp)
+ return -ENOMEM;
+ /* read-only data */
+ tmp->core = drbg->core;
+
+ ret = drbg_alloc_state(tmp);
+ if (ret)
+ goto err;
+
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg_copy_drbg(drbg, tmp);
+ tmp->d_ops = drbg->d_ops;
+ /* only make a link to the test buffer, as we only read that data */
+ tmp->test_data = drbg->test_data;
+ spin_unlock_bh(&drbg->drbg_lock);
+ *shadow = tmp;
+ return 0;
+
+err:
+ if (tmp)
+ kzfree(tmp);
+ return ret;
+}
+
+/*
+ * Restore shadow state into original DRBG state
+ */
+static void drbg_restore_shadow(struct drbg_state *drbg,
+ struct drbg_state **shadow)
+{
+ struct drbg_state *tmp = *shadow;
+
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg_copy_drbg(tmp, drbg);
+ spin_unlock_bh(&drbg->drbg_lock);
+ drbg_dealloc_state(tmp);
+ kzfree(tmp);
+ *shadow = NULL;
+}
+
+/*************************************************************************
+ * DRBG interface functions
+ *************************************************************************/
+
+/*
+ * DRBG generate function as required by SP800-90A - this function
+ * generates random numbers
+ *
+ * @drbg DRBG state handle
+ * @buf Buffer where to store the random numbers -- the buffer must already
+ * be pre-allocated by caller
+ * @buflen Length of output buffer - this value defines the number of random
+ * bytes pulled from DRBG
+ * @addtl Additional input that is mixed into state, may be NULL -- note
+ * the entropy is pulled by the DRBG internally unconditionally
+ * as defined in SP800-90A. The additional input is mixed into
+ * the state in addition to the pulled entropy.
+ *
+ * return: generated number of bytes
+ */
+static unsigned int drbg_generate(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ unsigned int len = 0;
+ struct drbg_state *shadow = NULL;
+
+ if (0 == buflen || !buf) {
+ pr_devel("DRBG: no buffer provided\n");
+ return 0;
+ }
+ if (addtl && NULL == addtl->buf && 0 < addtl->len) {
+ pr_devel("DRBG: wrong format of additional information\n");
+ return 0;
+ }
+
+ if (drbg_make_shadow(drbg, &shadow)) {
+ pr_devel("DRBG: shadow copy cannot be generated\n");
+ return 0;
+ }
+ /* 9.3.1 step 2 */
+ if (buflen > (drbg_max_request_bytes(shadow))) {
+ pr_devel("DRBG: requested random numbers too large %u\n",
+ buflen);
+ goto err;
+ }
+ /* 9.3.1 step 3 is implicit with the chosen DRBG */
+ /* 9.3.1 step 4 */
+ if (addtl && addtl->len > (drbg_max_addtl(shadow))) {
+ pr_devel("DRBG: additional information string too long %zu\n",
+ addtl->len);
+ goto err;
+ }
+ /* 9.3.1 step 5 is implicit with the chosen DRBG */
+ /* 9.3.1 step 6 and 9 supplemented by 9.3.2 step c -- the spec is a
+ * bit convoluted here, we make it simpler */
+ if ((drbg_max_requests(shadow)) < shadow->reseed_ctr)
+ shadow->seeded = false;
+
+ /* allocate cipher handle */
+ if (shadow->d_ops->crypto_init && shadow->d_ops->crypto_init(shadow))
+ goto err;
+
+ if (shadow->pr || !shadow->seeded) {
+ pr_devel("DRBG: reseeding before generation (prediction "
+ "resistance: %s, state %s)\n",
+ drbg->pr ? "true" : "false",
+ drbg->seeded ? "seeded" : "unseeded");
+ /* 9.3.1 steps 7.1 through 7.3 */
+ if (drbg_seed(shadow, addtl, true))
+ goto err;
+ /* 9.3.1 step 7.4 */
+ addtl = NULL;
+ }
+ /* 9.3.1 step 8 and 10 */
+ len = shadow->d_ops->generate(shadow, buf, buflen, addtl);
+
+ /* 10.1.1.4 step 6, 10.1.2.5 step 7, 10.2.1.5.2 step 7 */
+ shadow->reseed_ctr++;
+
+ /* 11.3.3 -- re-perform self tests after some generated random
+ * numbers, the chosen value after which self test is performed
+ * is arbitrary, but it should be reasonable */
+ /* Here we do not perform the self tests because of the following
+ * reasons: it is mathematically impossible that the initial self tests
+ * were successfully and the following are not. If the initial would
+ * pass and the following would not, the kernel integrity is violated.
+ * In this case, the entire kernel operation is questionable and it
+ * is unlikely that the integrity violation only affects to the
+ * correct operation of the DRBG.
+ */
+#if 0
+ if (shadow->reseed_ctr && !(shadow->reseed_ctr % 4096)) {
+ int err = 0;
+ pr_devel("DRBG: start to perform self test\n");
+ if (drbg->core->flags & DRBG_HMAC)
+ err = alg_test("drbg(pr(hmac(sha256)))",
+ "drbg(pr(hmac(sha256)))", 0, 0);
+ else if (drbg->core->flags & DRBG_CTR)
+ err = alg_test("drbg(pr(ctr(aes128)))",
+ "drbg(pr(ctr(aes128)))", 0, 0);
+ else
+ err = alg_test("drbg(pr(sha256))",
+ "drbg(pr(sha256))", 0, 0);
+ if (err) {
+ pr_err("DRBG: periodical self test failed\n");
+ /* uninstantiate implies that from now on, only errors
+ * are returned when reusing this DRBG cipher handle */
+ drbg_uninstantiate(drbg);
+ drbg_dealloc_state(shadow);
+ kzfree(shadow);
+ return 0;
+ } else {
+ pr_devel("DRBG: self test successful\n");
+ }
+ }
+#endif
+
+err:
+ if (shadow->d_ops->crypto_fini)
+ shadow->d_ops->crypto_fini(shadow);
+ drbg_restore_shadow(drbg, &shadow);
+ return len;
+}
+
+/*
+ * Wrapper around drbg_generate which can pull arbitrary long strings
+ * from the DRBG without hitting the maximum request limitation.
+ *
+ * Parameters: see drbg_generate
+ * Return codes: see drbg_generate -- if one drbg_generate request fails,
+ * the entire drbg_generate_long request fails
+ */
+static unsigned int drbg_generate_long(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ unsigned int len = 0;
+ unsigned int slice = 0;
+ do {
+ unsigned int tmplen = 0;
+ unsigned int chunk = 0;
+ slice = ((buflen - len) / drbg_max_request_bytes(drbg));
+ chunk = slice ? drbg_max_request_bytes(drbg) : (buflen - len);
+ tmplen = drbg_generate(drbg, buf + len, chunk, addtl);
+ if (!tmplen)
+ return 0;
+ len += tmplen;
+ } while (slice > 0);
+ return len;
+}
+
+/*
+ * DRBG instantiation function as required by SP800-90A - this function
+ * sets up the DRBG handle, performs the initial seeding and all sanity
+ * checks required by SP800-90A
+ *
+ * @drbg memory of state -- if NULL, new memory is allocated
+ * @pers Personalization string that is mixed into state, may be NULL -- note
+ * the entropy is pulled by the DRBG internally unconditionally
+ * as defined in SP800-90A. The additional input is mixed into
+ * the state in addition to the pulled entropy.
+ * @coreref reference to core
+ * @pr prediction resistance enabled
+ *
+ * return
+ * 0 on success
+ * error value otherwise
+ */
+static int drbg_instantiate(struct drbg_state *drbg, struct drbg_string *pers,
+ int coreref, bool pr)
+{
+ int ret = -ENOMEM;
+
+ pr_devel("DRBG: Initializing DRBG core %d with prediction resistance "
+ "%s\n", coreref, pr ? "enabled" : "disabled");
+ drbg->core = &cores[coreref];
+ drbg->pr = pr;
+ drbg->seeded = false;
+ switch (drbg->core->flags & DRBG_TYPE_MASK) {
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+ case DRBG_HMAC:
+ drbg->d_ops = &drbg_hmac_ops;
+ break;
+#endif /* CONFIG_CRYPTO_DRBG_HMAC */
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+ case DRBG_HASH:
+ drbg->d_ops = &drbg_hash_ops;
+ break;
+#endif /* CONFIG_CRYPTO_DRBG_HASH */
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+ case DRBG_CTR:
+ drbg->d_ops = &drbg_ctr_ops;
+ break;
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ /* 9.1 step 1 is implicit with the selected DRBG type -- see
+ * drbg_sec_strength() */
+
+ /* 9.1 step 2 is implicit as caller can select prediction resistance
+ * and the flag is copied into drbg->flags --
+ * all DRBG types support prediction resistance */
+
+ /* 9.1 step 4 is implicit in drbg_sec_strength */
+
+ /* no allocation of drbg as this is done by the kernel crypto API */
+ ret = drbg_alloc_state(drbg);
+ if (ret)
+ return ret;
+
+ ret = -EFAULT;
+ /* allocate cipher handle */
+ if (drbg->d_ops->crypto_init && drbg->d_ops->crypto_init(drbg))
+ goto err;
+ /* 9.1 step 6 through 11 */
+ ret = drbg_seed(drbg, pers, false);
+ /* deallocate cipher handle */
+ if (drbg->d_ops->crypto_fini)
+ drbg->d_ops->crypto_fini(drbg);
+ if (ret)
+ goto err;
+
+ return 0;
+
+err:
+ drbg_dealloc_state(drbg);
+ return ret;
+}
+
+/*
+ * DRBG uninstantiate function as required by SP800-90A - this function
+ * frees all buffers and the DRBG handle
+ *
+ * @drbg DRBG state handle
+ *
+ * return
+ * 0 on success
+ */
+static int drbg_uninstantiate(struct drbg_state *drbg)
+{
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg_dealloc_state(drbg);
+ /* no scrubbing of test_data -- this shall survive an uninstantiate */
+ spin_unlock_bh(&drbg->drbg_lock);
+ /* no freeing of drbg as this is done by the kernel crypto API */
+ return 0;
+}
+
+/*
+ * Helper function for setting the test data in the DRBG
+ *
+ * @drbg DRBG state handle
+ * @test_data test data to sets
+ */
+static inline void drbg_set_testdata(struct drbg_state *drbg,
+ struct drbg_test_data *test_data)
+{
+ if (!test_data || !test_data->testentropy)
+ return;
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg->test_data = test_data;
+ spin_unlock_bh(&drbg->drbg_lock);
+}
+
+/***************************************************************
+ * Kernel crypto APi cipher invocations requested by DRBG
+ ***************************************************************/
+
+#if defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_HMAC)
+struct sdesc {
+ struct shash_desc shash;
+ char ctx[];
+};
+
+static int drbg_init_hash_kernel(struct drbg_state *drbg)
+{
+ struct sdesc *sdesc;
+ struct crypto_shash *tfm;
+
+ tfm = crypto_alloc_shash(drbg->core->backend_cra_name, 0, 0);
+ if (IS_ERR(tfm)) {
+ pr_info("drbg: could not allocate digest TFM handle\n");
+ return PTR_ERR(tfm);
+ }
+ BUG_ON(drbg_blocklen(drbg) != crypto_shash_digestsize(tfm));
+ sdesc = kzalloc(sizeof(struct shash_desc) + crypto_shash_descsize(tfm),
+ GFP_KERNEL);
+ if (!sdesc) {
+ crypto_free_shash(tfm);
+ return -ENOMEM;
+ }
+
+ sdesc->shash.tfm = tfm;
+ sdesc->shash.flags = 0;
+ drbg->priv_data = sdesc;
+ return 0;
+}
+
+static int drbg_fini_hash_kernel(struct drbg_state *drbg)
+{
+ struct sdesc *sdesc = (struct sdesc *)drbg->priv_data;
+ if (sdesc) {
+ crypto_free_shash(sdesc->shash.tfm);
+ kzfree(sdesc);
+ }
+ drbg->priv_data = NULL;
+ return 0;
+}
+
+static int drbg_kcapi_hash(struct drbg_state *drbg, unsigned char *key,
+ unsigned char *outval, struct drbg_string *in)
+{
+ struct sdesc *sdesc = (struct sdesc *)drbg->priv_data;
+
+ if (key)
+ crypto_shash_setkey(sdesc->shash.tfm, key, drbg_statelen(drbg));
+ crypto_shash_init(&sdesc->shash);
+ for (; NULL != in; in = in->next)
+ crypto_shash_update(&sdesc->shash, in->buf, in->len);
+ return crypto_shash_final(&sdesc->shash, outval);
+}
+#endif /* (CONFIG_CRYPTO_DRBG_HASH || CONFIG_CRYPTO_DRBG_HMAC) */
+
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+static int drbg_init_sym_kernel(struct drbg_state *drbg)
+{
+ int ret = 0;
+ struct crypto_blkcipher *tfm;
+
+ tfm = crypto_alloc_blkcipher(drbg->core->backend_cra_name, 0, 0);
+ if (IS_ERR(tfm)) {
+ pr_info("drbg: could not allocate cipher TFM handle\n");
+ return PTR_ERR(tfm);
+ }
+ drbg->priv_data = tfm;
+ return ret;
+}
+
+static int drbg_fini_sym_kernel(struct drbg_state *drbg)
+{
+ struct crypto_blkcipher *tfm =
+ (struct crypto_blkcipher *)drbg->priv_data;
+ if (tfm)
+ crypto_free_blkcipher(tfm);
+ drbg->priv_data = NULL;
+ return 0;
+}
+
+static int drbg_kcapi_sym(struct drbg_state *drbg, unsigned char *key,
+ unsigned char *outval, struct drbg_string *in)
+{
+ int ret = 0;
+ struct scatterlist sg_in, sg_out;
+ struct blkcipher_desc desc;
+ struct crypto_blkcipher *tfm =
+ (struct crypto_blkcipher *)drbg->priv_data;
+
+ desc.tfm = tfm;
+ desc.flags = 0;
+ crypto_blkcipher_setkey(tfm, key, (drbg_keylen(drbg)));
+ /* in is only component */
+ sg_init_one(&sg_in, in->buf, in->len);
+ sg_init_one(&sg_out, outval, drbg_blocklen(drbg));
+ ret = crypto_blkcipher_encrypt(&desc, &sg_out, &sg_in, in->len);
+
+ return ret;
+}
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+
+/***************************************************************
+ * Kernel crypto API interface to register DRBG
+ ***************************************************************/
+
+/*
+ * Look up the DRBG flags by given kernel crypto API cra_name
+ * The code uses the cores definition to do this
+ *
+ * @cra_name kernel crypto API cra_name
+ * @coreref reference to integer which is filled with the pointer to
+ * the applicable core
+ * @pr reference for setting prediction resistance
+ *
+ * return: flags
+ */
+static inline void drbg_convert_tfm_core(const char *cra_name,
+ int *coreref, bool *pr)
+{
+ int i = 0;
+ size_t start = 0;
+ int len = 0;
+
+ *pr = true;
+ /* disassemble the names */
+ if (0 == memcmp(cra_name, "drbg(nopr(", 10)) {
+ start = 10;
+ *pr = false;
+ } else if (0 == memcmp(cra_name, "drbg(pr(", 8)) {
+ start = 8;
+ } else {
+ return;
+ }
+
+ /* remove the first part and the closing parenthesis */
+ len = strlen(cra_name) - start - 2;
+ for (i = 0; ARRAY_SIZE(cores) > i; i++) {
+ if (0 == memcmp(cra_name + start, cores[i].cra_name, len)) {
+ *coreref = i;
+ return;
+ }
+ }
+}
+
+/*
+ * Initialize one DRBG invoked by the kernel crypto API
+ *
+ * Function uses the kernel crypto API cra_name to look up
+ * the flags to instantiate the DRBG
+ */
+static int drbg_kcapi_init(struct crypto_tfm *tfm)
+{
+ struct drbg_state *drbg = crypto_tfm_ctx(tfm);
+ bool pr = false;
+ int coreref = 0;
+
+ drbg_convert_tfm_core(crypto_tfm_alg_name(tfm), &coreref, &pr);
+ /* when personalization string is needed, the caller must call reset
+ * and provide the personalization string as seed information */
+ return drbg_instantiate(drbg, NULL, coreref, pr);
+}
+
+static void drbg_kcapi_cleanup(struct crypto_tfm *tfm)
+{
+ drbg_uninstantiate(crypto_tfm_ctx(tfm));
+}
+
+/*
+ * Generate random numbers invoked by the kernel crypto API:
+ * The API of the kernel crypto API is extended as follows:
+ *
+ * If dlen is larger than zero, rdata is interpreted as the output buffer
+ * where random data is to be stored.
+ *
+ * If dlen is zero, rdata is interpreted as a pointer to a struct drbg_gen
+ * which holds the additional information string that is used for the
+ * DRBG generation process. The output buffer that is to be used to store
+ * data is also pointed to by struct drbg_gen.
+ *
+ */
+static int drbg_kcapi_random(struct crypto_rng *tfm, u8 *rdata,
+ unsigned int dlen)
+{
+ struct drbg_state *drbg = crypto_rng_ctx(tfm);
+ if (0 < dlen) {
+ return drbg_generate_long(drbg, rdata, dlen, NULL);
+ } else {
+ struct drbg_gen *data = (struct drbg_gen *)rdata;
+ /* catch NULL pointer */
+ if (!data)
+ return 0;
+ drbg_set_testdata(drbg, data->test_data);
+ return drbg_generate_long(drbg, data->outbuf, data->outlen,
+ data->addtl);
+ }
+}
+
+/*
+ * Reset the DRBG invoked by the kernel crypto API
+ * The reset implies a full re-initialization of the DRBG. Similar to the
+ * generate function of drbg_kcapi_random, this function extends the
+ * kernel crypto API interface with struct drbg_gen
+ */
+static int drbg_kcapi_reset(struct crypto_rng *tfm, u8 *seed, unsigned int slen)
+{
+ struct drbg_state *drbg = crypto_rng_ctx(tfm);
+ struct crypto_tfm *tfm_base = crypto_rng_tfm(tfm);
+ bool pr = false;
+ struct drbg_string seed_string;
+ int coreref = 0;
+
+ drbg_uninstantiate(drbg);
+ drbg_convert_tfm_core(crypto_tfm_alg_name(tfm_base), &coreref, &pr);
+ if (0 < slen) {
+ drbg_string_fill(&seed_string, seed, slen);
+ return drbg_instantiate(drbg, &seed_string, coreref, pr);
+ } else {
+ struct drbg_gen *data = (struct drbg_gen *)seed;
+ /* allow invocation of API call with NULL, 0 */
+ if (!data)
+ return drbg_instantiate(drbg, NULL, coreref, pr);
+ drbg_set_testdata(drbg, data->test_data);
+ return drbg_instantiate(drbg, data->addtl, coreref, pr);
+ }
+}
+
+/***************************************************************
+ * Kernel module: code to load the module
+ ***************************************************************/
+
+/*
+ * Tests as defined in 11.3.2 in addition to the cipher tests: testing
+ * of the error handling.
+ *
+ * Note, testing of failing seed source as defined in 11.3.2 is not applicable
+ * as seed source of get_random_bytes does not fail.
+ * Note, testing the reseed counter is not done as an automatic reseeding
+ * is performed in drbg_generate when the reseed counter is too large.
+ */
+static inline int __init drbg_healthcheck_sanity(void)
+{
+#ifdef CONFIG_CRYPTO_FIPS
+ unsigned int len = 0;
+#define OUTBUFLEN 16
+ unsigned char buf[OUTBUFLEN];
+ struct drbg_state *drbg = NULL;
+ int ret = -EFAULT;
+ int rc = -EFAULT;
+ bool pr = false;
+ int coreref = 0;
+ struct drbg_string addtl;
+ size_t max_addtllen, max_request_bytes;
+
+ /* only perform test in FIPS mode */
+ if (0 == fips_enabled)
+ return 0;
+
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+ drbg_convert_tfm_core("drbg(nopr(ctr(aes128)))", &coreref, &pr);
+#elif CONFIG_CRYPTO_DRBG_HASH
+ drbg_convert_tfm_core("drbg(nopr(sha256)", &coreref, &pr);
+#else
+ drbg_convert_tfm_core("drbg(nopr(hmac(sha256)))", &coreref, &pr);
+#endif
+
+ drbg = kzalloc(sizeof(struct drbg_state), GFP_KERNEL);
+ if (!drbg)
+ return -ENOMEM;
+
+ /* if the following tests fail, it is likely that there is a buffer
+ * overflow as buf is much smaller than the requested or provided
+ * string lengths -- in case the error handling does not succeed
+ * we may get an OOPS. And we want to get an OOPS as this is a
+ * grave bug */
+
+ /* get a valid instance of DRBG for following tests */
+ ret = drbg_instantiate(drbg, NULL, coreref, pr);
+ if (ret)
+ goto outbuf;
+ max_addtllen = drbg_max_addtl(drbg);
+ max_request_bytes = drbg_max_request_bytes(drbg);
+ drbg_string_fill(&addtl, buf, max_addtllen + 1);
+ /* overflow addtllen with additonal info string */
+ len = drbg_generate(drbg, buf, OUTBUFLEN, &addtl);
+ if (len)
+ goto outdrbg;
+ /* overflow max_bits */
+ len = drbg_generate(drbg, buf, (max_request_bytes + 1), NULL);
+ if (len)
+ goto outdrbg;
+ drbg_uninstantiate(drbg);
+
+ /* overflow max addtllen with personalization string */
+ ret = drbg_instantiate(drbg, &addtl, coreref, pr);
+ if (0 == ret)
+ goto outdrbg;
+ /* test uninstantated DRBG */
+ len = drbg_generate(drbg, buf, (max_request_bytes + 1), NULL);
+ if (!len)
+ /* all tests passed */
+ rc = 0;
+
+ pr_devel("DRBG: Sanity tests for failure code paths successfully "
+ "completed\n");
+outdrbg:
+ drbg_uninstantiate(drbg);
+outbuf:
+ kzfree(drbg);
+ return rc;
+#else /* CONFIG_CRYPTO_FIPS */
+ return 0;
+#endif /* CONFIG_CRYPTO_FIPS */
+}
+
+
+static struct crypto_alg drbg_algs[22];
+
+/*
+ * Fill the array drbg_algs used to register the different DRBGs
+ * with the kernel crypto API. To fill the array, the information
+ * from cores[] is used.
+ */
+static inline void __init drbg_fill_array(unsigned long i, unsigned long j,
+ int pr)
+{
+ int pos = 0;
+
+ memset(&drbg_algs[i], 0, sizeof(struct crypto_alg));
+ if (pr) {
+ memcpy(drbg_algs[i].cra_name, "drbg(pr(", 8);
+ memcpy(drbg_algs[i].cra_driver_name, "drbg_pr_", 8);
+ pos = 8;
+ } else {
+ memcpy(drbg_algs[i].cra_name, "drbg(nopr(", 10);
+ memcpy(drbg_algs[i].cra_driver_name, "drbg_nopr_", 10);
+ pos = 10;
+ }
+ memcpy(drbg_algs[i].cra_name + pos, cores[j].cra_name,
+ strlen(cores[j].cra_name));
+ memcpy(drbg_algs[i].cra_name + pos + strlen(cores[j].cra_name), "))",
+ 2);
+ memcpy(drbg_algs[i].cra_driver_name + pos,
+ cores[j].cra_driver_name, strlen(cores[j].cra_driver_name));
+ drbg_algs[i].cra_priority = 100;
+ drbg_algs[i].cra_flags = CRYPTO_ALG_TYPE_RNG;
+ drbg_algs[i].cra_ctxsize = sizeof(struct drbg_state);
+ drbg_algs[i].cra_type = &crypto_rng_type;
+ drbg_algs[i].cra_module = THIS_MODULE;
+ drbg_algs[i].cra_init = drbg_kcapi_init;
+ drbg_algs[i].cra_exit = drbg_kcapi_cleanup;
+ drbg_algs[i].cra_u.rng.rng_make_random = drbg_kcapi_random;
+ drbg_algs[i].cra_u.rng.rng_reset = drbg_kcapi_reset;
+ drbg_algs[i].cra_u.rng.seedsize = 0;
+}
+
+static int __init drbg_init(void)
+{
+ unsigned int i = 0; /* pointer to drbg_algs */
+ unsigned int j = 0; /* pointer to cores */
+ int ret = -EFAULT;
+
+ ret = drbg_healthcheck_sanity();
+ if (ret)
+ return ret;
+
+ if (ARRAY_SIZE(cores) * 2 > ARRAY_SIZE(drbg_algs))
+ pr_info("drbg: Not all available DRBGs registered"
+ "(slots needed: %lu, slots available: %lu)\n",
+ ARRAY_SIZE(cores) * 2, ARRAY_SIZE(drbg_algs));
+
+ /* each DRBG definition can be used with PR and without PR, thus
+ * we instantiate each DRBG in cores[] twice */
+ for (j = 0; ARRAY_SIZE(cores) > j; j++) {
+ drbg_fill_array(i, j, 1);
+ i++;
+ drbg_fill_array(i, j, 0);
+ i++;
+ }
+ return crypto_register_algs(drbg_algs, (ARRAY_SIZE(cores) * 2));
+}
+
+void __exit drbg_exit(void)
+{
+ crypto_unregister_algs(drbg_algs, (ARRAY_SIZE(cores) * 2));
+}
+
+module_init(drbg_init);
+module_exit(drbg_exit);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Stephan Mueller <smueller@chronox.de>");
+MODULE_DESCRIPTION("NIST SP800-90A Deterministic Random Bit Generator (DRBG) using following cores:"
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+"HMAC "
+#endif
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+"Hash "
+#endif
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+"CTR"
+#endif
+);
^ permalink raw reply related [flat|nested] 29+ messages in thread* [PATCH v3 1/6] SP800-90A Deterministic Random Bit Generator
2014-03-17 7:34 ` [PATCH v2 " Stephan Mueller
` (3 preceding siblings ...)
2014-03-27 19:53 ` [PATCH v3 " Stephan Mueller
@ 2014-03-27 19:56 ` Stephan Mueller
2014-04-11 18:07 ` [PATCH v4 " Stephan Mueller
4 siblings, 1 reply; 29+ messages in thread
From: Stephan Mueller @ 2014-03-27 19:56 UTC (permalink / raw)
To: linux-kernel, linux-crypto; +Cc: aquini, jeremy.wayne.powell, clemens, pwalten
Changes v3:
* fix invocation of drbg_sec_strength to determine the amount of seed needed
for the DRBG. The function returns information as a byte value, but the
invoker assumed a bit value.
* change default value returned by drbg_sec_strength to be the maximum entropy
defined by SP800-90A to catch erroneous invocations of the function.
* Fix invocaction of d_ops in drbg_generate: drbg->d_ops ==> shadow->d_ops
* Make return of drbg_fips_continuous_test cleaner as suggested by
Clemens Ladisch
* Fix comments on how to invoke the DRBG at the beginning of the file
* drbg_ctr_df: replace the for loop for calculation of padlen that used to
call up to 16 modulo operations with one modulo operation
* drbg_ctr_df: replace plain integer values with sizeof() to make code clearer
* drbg_hash_hashgen: replace memset() on drbg->scratchpad with memset()
on src/dst pointers to make code clearer
* as recommended by Peter Waltenberg: add re-invocation of self tests as
required by 11.3.3 -- the tests are commented out because they make no
mathematical sense. However, if a FIPS 140-2 validation requires these
tests, the code just needs to be activated.
* as recommended by Peter Waltenberg: add error path tests as required by
11.3.2 -- see new function of drbg_healthcheck_sanity
* add debug printk
* perform testing in FIPS 140-2 mode
* as recommended by Peter Waltenberg: add drbg_generate_long to generate
arbitrary long strings
Signed-off-by: Stephan Mueller <smueller@chronox.de>
---
create mode 100644 crypto/drbg.c
diff --git a/crypto/drbg.c b/crypto/drbg.c
new file mode 100644
index 0000000..6c866ef
--- /dev/null
+++ b/crypto/drbg.c
@@ -0,0 +1,1975 @@
+/*
+ * DRBG: Deterministic Random Bits Generator
+ * Based on NIST Recommended DRBG from NIST SP800-90A with the following
+ * properties:
+ * * CTR DRBG with DF with AES-128, AES-192, AES-256 cores
+ * * Hash DRBG with DF with SHA-1, SHA-256, SHA-384, SHA-512 cores
+ * * HMAC DRBG with DF with SHA-1, SHA-256, SHA-384, SHA-512 cores
+ * * with and without prediction resistance
+ *
+ * Copyright Stephan Mueller <smueller@chronox.de>, 2014
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, and the entire permission notice in its entirety,
+ * including the disclaimer of warranties.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote
+ * products derived from this software without specific prior
+ * written permission.
+ *
+ * ALTERNATIVELY, this product may be distributed under the terms of
+ * the GNU General Public License, in which case the provisions of the GPL are
+ * required INSTEAD OF the above restrictions. (This clause is
+ * necessary due to a potential bad interaction between the GPL and
+ * the restrictions contained in a BSD-style copyright.)
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF
+ * WHICH ARE HEREBY DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+ * USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * DRBG Usage
+ * ==========
+ * The SP 800-90A DRBG allows the user to specify a personalization string
+ * for initialization as well as an additional information string for each
+ * random number request. The following code fragments show how a caller
+ * uses the kernel crypto API to use the full functionality of the DRBG.
+ *
+ * Usage without any additional data
+ * ---------------------------------
+ * struct crypto_rng *drng;
+ * int err;
+ * char data[DATALEN];
+ *
+ * drng = crypto_alloc_rng(drng_name, 0, 0);
+ * err = crypto_rng_get_bytes(drng, &data, DATALEN);
+ * crypto_free_rng(drng);
+ *
+ *
+ * Usage with personalization string during initialization
+ * -------------------------------------------------------
+ * struct crypto_rng *drng;
+ * int err;
+ * char data[DATALEN];
+ * struct drbg_string pers;
+ * char personalization[11] = "some-string";
+ *
+ * drbg_string_fill(&pers, personalization, strlen(personalization));
+ * drng = crypto_alloc_rng(drng_name, 0, 0);
+ * // The reset completely re-initializes the DRBG with the provided
+ * // personalization string
+ * err = crypto_rng_reset(drng, &personalization, strlen(personalization));
+ * err = crypto_rng_get_bytes(drng, &data, DATALEN);
+ * crypto_free_rng(drng);
+ *
+ *
+ * Usage with additional information string during random number request
+ * ---------------------------------------------------------------------
+ * struct crypto_rng *drng;
+ * int err;
+ * char data[DATALEN];
+ * char addtl_string[11] = "some-string";
+ * string drbg_string addtl;
+ *
+ * drbg_string_fill(&addtl, addtl_string, strlen(addtl_string));
+ * drng = crypto_alloc_rng(drng_name, 0, 0);
+ * // The following call is a wrapper to crypto_rng_get_bytes() and returns
+ * // the same error codes.
+ * err = crypto_drbg_get_bytes_addtl(drng, &data, DATALEN, &addtl);
+ * crypto_free_rng(drng);
+ *
+ *
+ * Usage with personalization and additional information strings
+ * -------------------------------------------------------------
+ * Just mix both scenarios above.
+ */
+
+#include <crypto/drbg.h>
+
+#if !defined(CONFIG_CRYPTO_DRBG_HASH) && \
+ !defined(CONFIG_CRYPTO_DRBG_HMAC) && \
+ !defined(CONFIG_CRYPTO_DRBG_CTR)
+#warning "The DRBG code is useless without compiling at least one DRBG type"
+#endif
+
+/***************************************************************
+ * Backend cipher definitions available to DRBG
+ ***************************************************************/
+
+const struct drbg_core cores[] = {
+ /* Hash DRBGs */
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+ {
+ .flags = DRBG_HASH | DRBG_STRENGTH128,
+ .statelen = 55, /* 440 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 20,
+ .cra_name = "sha1",
+ .cra_driver_name = "sha1",
+ .backend_cra_name = "sha1",
+ }, {
+ .flags = DRBG_HASH | DRBG_STRENGTH256,
+ .statelen = 55, /* 440 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 32,
+ .cra_name = "sha256",
+ .cra_driver_name = "sha256",
+ .backend_cra_name = "sha256",
+ }, {
+ .flags = DRBG_HASH | DRBG_STRENGTH256,
+ .statelen = 111, /* 888 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 48,
+ .cra_name = "sha384",
+ .cra_driver_name = "sha384",
+ .backend_cra_name = "sha384",
+ }, {
+ .flags = DRBG_HASH | DRBG_STRENGTH256,
+ .statelen = 111, /* 888 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 64,
+ .cra_name = "sha512",
+ .cra_driver_name = "sha512",
+ .backend_cra_name = "sha512",
+ },
+#endif /* CONFIG_CRYPTO_DRBG_HASH */
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+ {
+ /* HMAC DRBGs */
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 20, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 20,
+ .cra_name = "hmac(sha1)",
+ .cra_driver_name = "hmac_sha1",
+ .backend_cra_name = "hmac(sha1)",
+ }, {
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 32, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 32,
+ .cra_name = "hmac(sha256)",
+ .cra_driver_name = "hmac_sha256",
+ .backend_cra_name = "hmac(sha256)",
+ }, {
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 48, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 48,
+ .cra_name = "hmac(sha384)",
+ .cra_driver_name = "hmac_sha384",
+ .backend_cra_name = "hmac(sha384)",
+ }, {
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 64, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 64,
+ .cra_name = "hmac(sha512)",
+ .cra_driver_name = "hmac_sha512",
+ .backend_cra_name = "hmac(sha512)",
+ },
+#endif /* CONFIG_CRYPTO_DRBG_HMAC */
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+ {
+ /* block ciphers */
+ .flags = DRBG_CTR | DRBG_STRENGTH128,
+ .statelen = 32, /* 256 bits as defined in 10.2.1 */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 16,
+ .cra_name = "ctr(aes128)",
+ .cra_driver_name = "ctr_aes128",
+ .backend_cra_name = "ecb(aes)",
+ }, {
+ /* block ciphers */
+ .flags = DRBG_CTR | DRBG_STRENGTH192,
+ .statelen = 40, /* 320 bits as defined in 10.2.1 */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 16,
+ .cra_name = "ctr(aes192)",
+ .cra_driver_name = "ctr_aes192",
+ .backend_cra_name = "ecb(aes)",
+ }, {
+ /* block ciphers */
+ .flags = DRBG_CTR | DRBG_STRENGTH256,
+ .statelen = 48, /* 384 bits as defined in 10.2.1 */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 16,
+ .cra_name = "ctr(aes256)",
+ .cra_driver_name = "ctr_aes256",
+ .backend_cra_name = "ecb(aes)",
+ },
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+};
+
+/******************************************************************
+ * Generic helper functions
+ ******************************************************************/
+
+/*
+ * Return strength of DRBG according to SP800-90A section 8.4
+ *
+ * @flags DRBG flags reference
+ *
+ * Return: normalized strength in *bytes* value or 32 as default
+ * to counter programming errors
+ */
+static inline unsigned short drbg_sec_strength(drbg_flag_t flags)
+{
+ switch (flags & DRBG_STRENGTH_MASK) {
+ case DRBG_STRENGTH128:
+ return 16;
+ case DRBG_STRENGTH192:
+ return 24;
+ case DRBG_STRENGTH256:
+ return 32;
+ default:
+ return 32;
+ }
+}
+
+/*
+ * FIPS 140-2 continuous self test
+ * The test is performed on the result of one round of the output
+ * function. Thus, the function implicitly knows the size of the
+ * buffer.
+ *
+ * The FIPS test can be called in an endless loop until it returns
+ * true. Although the code looks like a potential for a deadlock, it
+ * is not the case, because returning a false cannot mathematically
+ * occur (except once when a reseed took place and the updated state
+ * would is now set up such that the generation of new value returns
+ * an identical one -- this is most unlikely and would happen only once).
+ * Thus, if this function repeatedly returns false and thus would cause
+ * a deadlock, the integrity of the entire kernel is lost.
+ *
+ * @drbg DRBG handle
+ * @buf output buffer of random data to be checked
+ *
+ * return:
+ * true on success
+ * false on error
+ */
+static bool drbg_fips_continuous_test(struct drbg_state *drbg,
+ unsigned char *buf)
+{
+#ifdef CONFIG_CRYPTO_FIPS
+ int ret = 0;
+ /* skip test if we test the overall system */
+ if (drbg->test_data)
+ return true;
+ /* only perform test in FIPS mode */
+ if (0 == fips_enabled)
+ return true;
+ if (!drbg->fips_primed) {
+ /* Priming of FIPS test */
+ memcpy(drbg->prev, buf, drbg_blocklen(drbg));
+ drbg->fips_primed = true;
+ /* return false due to priming, i.e. another round is needed */
+ return false;
+ }
+ ret = memcmp(drbg->prev, buf, drbg_blocklen(drbg));
+ memcpy(drbg->prev, buf, drbg_blocklen(drbg));
+ /* the test shall pass when the two compared values are not equal */
+ return ret != 0;
+#else
+ return true;
+#endif /* CONFIG_CRYPTO_FIPS */
+}
+
+/*
+ * Convert an integer into a byte representation of this integer.
+ * The byte representation is big-endian
+ *
+ * @buf buffer holding the converted integer
+ * @val value to be converted
+ * @buflen length of buffer
+ */
+#if (defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_CTR))
+static inline void drbg_int2byte(unsigned char *buf, uint64_t val,
+ size_t buflen)
+{
+ unsigned char *byte;
+ uint64_t i;
+
+ byte = buf + (buflen - 1);
+ for (i = 0; i < buflen; i++)
+ *(byte--) = val >> (i * 8) & 0xff;
+}
+
+/*
+ * Increment buffer
+ *
+ * @dst buffer to increment
+ * @add value to add
+ */
+static inline void drbg_add_buf(unsigned char *dst, size_t dstlen,
+ unsigned char *add, size_t addlen)
+{
+ /* implied: dstlen > addlen */
+ unsigned char *dstptr, *addptr;
+ unsigned int remainder = 0;
+ size_t len = addlen;
+
+ dstptr = dst + (dstlen-1);
+ addptr = add + (addlen-1);
+ while (len) {
+ remainder += *dstptr + *addptr;
+ *dstptr = remainder & 0xff;
+ remainder >>= 8;
+ len--; dstptr--; addptr--;
+ }
+ len = dstlen - addlen;
+ while (len && remainder > 0) {
+ remainder = *dstptr + 1;
+ *dstptr = remainder & 0xff;
+ remainder >>= 8;
+ len--; dstptr--;
+ }
+}
+#endif /* defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_CTR) */
+
+/******************************************************************
+ * CTR DRBG callback functions
+ ******************************************************************/
+
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+static int drbg_kcapi_sym(struct drbg_state *drbg, unsigned char *key,
+ unsigned char *outval, struct drbg_string *in);
+static int drbg_init_sym_kernel(struct drbg_state *drbg);
+static int drbg_fini_sym_kernel(struct drbg_state *drbg);
+
+/* BCC function for CTR DRBG as defined in 10.4.3 */
+static int drbg_ctr_bcc(struct drbg_state *drbg,
+ unsigned char *out, unsigned char *key,
+ struct drbg_string *in)
+{
+ int ret = -EFAULT;
+ struct drbg_string *curr = in;
+ size_t inpos = curr->len;
+ const unsigned char *pos = curr->buf;
+ struct drbg_string data;
+
+ drbg_string_fill(&data, out, drbg_blocklen(drbg));
+
+ /* 10.4.3 step 1 */
+ memset(out, 0, drbg_blocklen(drbg));
+
+ /* 10.4.3 step 2 / 4 */
+ while (inpos) {
+ short cnt = 0;
+ /* 10.4.3 step 4.1 */
+ for (cnt = 0; cnt < drbg_blocklen(drbg); cnt++) {
+ out[cnt] ^= *pos;
+ pos++; inpos--;
+ /* the following branch implements the linked list
+ * iteration. If we are at the end of the current data
+ * set, we have to start using the next data set if
+ * available -- the inpos value always points to the
+ * current byte and will be zero if we have processed
+ * the last byte of the last linked list member */
+ if (0 == inpos) {
+ curr = curr->next;
+ if (NULL != curr) {
+ pos = curr->buf;
+ inpos = curr->len;
+ } else {
+ inpos = 0;
+ break;
+ }
+ }
+ }
+ /* 10.4.3 step 4.2 */
+ ret = drbg_kcapi_sym(drbg, key, out, &data);
+ if (ret)
+ return ret;
+ /* 10.4.3 step 2 */
+ }
+ return 0;
+}
+
+/*
+ * scratchpad usage: drbg_ctr_update is interlinked with drbg_ctr_df
+ * (and drbg_ctr_bcc, but this function does not need any temporary buffers),
+ * the scratchpad is used as follows:
+ * drbg_ctr_update:
+ * temp
+ * start: drbg->scratchpad
+ * length: drbg_statelen(drbg) + drbg_blocklen(drbg)
+ * note: the cipher writing into this variable works
+ * blocklen-wise. Now, when the statelen is not a multiple
+ * of blocklen, the generateion loop below "spills over"
+ * by at most blocklen. Thus, we need to give sufficient
+ * memory.
+ * df_data
+ * start: drbg->scratchpad +
+ * drbg_statelen(drbg) + drbg_blocklen(drbg)
+ * length: drbg_statelen(drbg)
+ *
+ * drbg_ctr_df:
+ * pad
+ * start: df_data + drbg_statelen(drbg)
+ * length: drbg_blocklen(drbg)
+ * iv
+ * start: pad + drbg_blocklen(drbg)
+ * length: drbg_blocklen(drbg)
+ * temp
+ * start: iv + drbg_blocklen(drbg)
+ * length: (drbg_keylen(drbg) + drbg_blocklen(drbg) ==
+ * drbg_statelen(drbg))
+ */
+
+/* Derivation Function for CTR DRBG as defined in 10.4.2 */
+static int drbg_ctr_df(struct drbg_state *drbg,
+ unsigned char *df_data, size_t bytes_to_return,
+ struct drbg_string *addtl)
+{
+ int ret = -EFAULT;
+ unsigned char L_N[8];
+ /* S3 is input */
+ struct drbg_string S1, S2, S4, cipherin;
+ struct drbg_string *tempstr = addtl;
+ unsigned char *pad = df_data + drbg_statelen(drbg);
+ unsigned char *iv = pad + drbg_blocklen(drbg);
+ unsigned char *temp = iv + drbg_blocklen(drbg);
+ size_t padlen = 0;
+ unsigned int templen = 0;
+ /* 10.4.2 step 7 */
+ unsigned int i = 0;
+ /* 10.4.2 step 8 */
+ unsigned char *K = (unsigned char *)
+ "\x00\x01\x02\x03\x04\x05\x06\x07"
+ "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f"
+ "\x10\x11\x12\x13\x14\x15\x16\x17"
+ "\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f";
+ unsigned char *X;
+ size_t generated_len = 0;
+ size_t inputlen = 0;
+
+ memset(pad, 0, drbg_blocklen(drbg));
+ memset(iv, 0, drbg_blocklen(drbg));
+ memset(temp, 0, drbg_statelen(drbg));
+
+ /* 10.4.2 step 1 is implicit as we work byte-wise */
+
+ /* 10.4.2 step 2 */
+ if ((512/8) < bytes_to_return)
+ return -EINVAL;
+
+ /* 10.4.2 step 2 -- calculate the entire length of all input data */
+ for (; NULL != tempstr; tempstr = tempstr->next)
+ inputlen += tempstr->len;
+ drbg_int2byte(&L_N[0], inputlen, 4);
+
+ /* 10.4.2 step 3 */
+ drbg_int2byte(&L_N[4], bytes_to_return, 4);
+
+ /* 10.4.2 step 5: length is L_N, input_string, one byte, padding */
+ padlen = (inputlen + sizeof(L_N) + 1) % (drbg_blocklen(drbg));
+ /* wrap the padlen appropriately */
+ if (padlen)
+ padlen = drbg_blocklen(drbg) - padlen;
+ /* pad / padlen contains the 0x80 byte and the following zero bytes, so
+ * add one for byte for 0x80 */
+ padlen++;
+ pad[0] = 0x80;
+
+ /* 10.4.2 step 4 -- first fill the linked list and then order it */
+ drbg_string_fill(&S1, iv, drbg_blocklen(drbg));
+ drbg_string_fill(&S2, L_N, sizeof(L_N));
+ drbg_string_fill(&S4, pad, padlen);
+ S1.next = &S2;
+ S2.next = addtl;
+ /* splice in addtl between S2 and S4 -- we place S4 at the end of the
+ * input data chain */
+ tempstr = addtl;
+ for (; NULL != tempstr; tempstr = tempstr->next)
+ if (NULL == tempstr->next)
+ break;
+ tempstr->next = &S4;
+
+ /* 10.4.2 step 9 */
+ while (templen < (drbg_keylen(drbg) + (drbg_blocklen(drbg)))) {
+ /* 10.4.2 step 9.1 - the padding is implicit as the buffer
+ * holds zeros after allocation -- even the increment of i
+ * is irrelevant as the increment remains within length of i */
+ drbg_int2byte(iv, i, 4);
+ /* 10.4.2 step 9.2 -- BCC and concatenation with temp */
+ ret = drbg_ctr_bcc(drbg, temp + templen, K, &S1);
+ if (ret)
+ goto out;
+ /* 10.4.2 step 9.3 */
+ i++;
+ templen += drbg_blocklen(drbg);
+ }
+
+ /* 10.4.2 step 11 */
+ /* implicit key len with seedlen - blocklen according to table 3 */
+ X = temp + (drbg_keylen(drbg));
+ drbg_string_fill(&cipherin, X, drbg_blocklen(drbg));
+
+ /* 10.4.2 step 12: overwriting of outval */
+
+ /* 10.4.2 step 13 */
+ while (generated_len < bytes_to_return) {
+ short blocklen = 0;
+ /* 10.4.2 step 13.1 */
+ /* the truncation of the key length is implicit as the key
+ * is only drbg_blocklen in size -- check for the implementation
+ * of the cipher function callback */
+ ret = drbg_kcapi_sym(drbg, temp, X, &cipherin);
+ if (ret)
+ goto out;
+ blocklen = (drbg_blocklen(drbg) <
+ (bytes_to_return - generated_len)) ?
+ drbg_blocklen(drbg) :
+ (bytes_to_return - generated_len);
+ /* 10.4.2 step 13.2 and 14 */
+ memcpy(df_data + generated_len, X, blocklen);
+ generated_len += blocklen;
+ }
+
+ ret = 0;
+
+out:
+ memset(iv, 0, drbg_blocklen(drbg));
+ memset(temp, 0, drbg_statelen(drbg));
+ memset(pad, 0, drbg_blocklen(drbg));
+ return ret;
+}
+
+/* update function of CTR DRBG as defined in 10.2.1.2 */
+static int drbg_ctr_update(struct drbg_state *drbg,
+ struct drbg_string *addtl, int reseed)
+{
+ int ret = -EFAULT;
+ /* 10.2.1.2 step 1 */
+ unsigned char *temp = drbg->scratchpad;
+ unsigned char *df_data = drbg->scratchpad + drbg_statelen(drbg) +
+ drbg_blocklen(drbg);
+ unsigned char *temp_p, *df_data_p; /* pointer to iterate over buffers */
+ unsigned int len = 0;
+ struct drbg_string cipherin;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ memset(temp, 0, drbg_statelen(drbg) + drbg_blocklen(drbg));
+ memset(df_data, 0, drbg_statelen(drbg));
+
+ /* 10.2.1.3.2 step 2 and 10.2.1.4.2 step 2 */
+ if (addtl && 0 < addtl->len) {
+ ret = drbg_ctr_df(drbg, df_data, drbg_statelen(drbg),
+ addtl);
+ if (ret)
+ goto out;
+ }
+
+ drbg_string_fill(&cipherin, drbg->V, drbg_blocklen(drbg));
+ /* 10.2.1.3.2 step 2 and 3 -- are already covered as we memset(0)
+ * all memory during initialization */
+ while (len < (drbg_statelen(drbg))) {
+ /* 10.2.1.2 step 2.1 */
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ /* 10.2.1.2 step 2.2 */
+ /* using target of temp + len: 10.2.1.2 step 2.3 and 3 */
+ ret = drbg_kcapi_sym(drbg, drbg->C, temp + len, &cipherin);
+ if (ret)
+ goto out;
+ /* 10.2.1.2 step 2.3 and 3 */
+ len += drbg_blocklen(drbg);
+ }
+
+ /* 10.2.1.2 step 4 */
+ temp_p = temp;
+ df_data_p = df_data;
+ for (len = 0; len < drbg_statelen(drbg); len++) {
+ *temp_p ^= *df_data_p;
+ df_data_p++; temp_p++;
+ }
+
+ /* 10.2.1.2 step 5 */
+ memcpy(drbg->C, temp, drbg_keylen(drbg));
+ /* 10.2.1.2 step 6 */
+ memcpy(drbg->V, temp + drbg_keylen(drbg), drbg_blocklen(drbg));
+ ret = 0;
+
+out:
+ memset(temp, 0, drbg_statelen(drbg) + drbg_blocklen(drbg));
+ memset(df_data, 0, drbg_statelen(drbg));
+ return ret;
+}
+
+/*
+ * scratchpad use: drbg_ctr_update is called independently from
+ * drbg_ctr_extract_bytes. Therefore, the scratchpad is reused
+ */
+/* Generate function of CTR DRBG as defined in 10.2.1.5.2 */
+static unsigned int drbg_ctr_generate(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ unsigned int len = 0;
+ struct drbg_string data;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+
+ /* 10.2.1.5.2 step 2 */
+ if (addtl && 0 < addtl->len) {
+ addtl->next = NULL;
+ if (drbg_ctr_update(drbg, addtl, 1))
+ return 0;
+ }
+
+ /* 10.2.1.5.2 step 4.1 */
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ drbg_string_fill(&data, drbg->V, drbg_blocklen(drbg));
+ while (len < buflen) {
+ unsigned int outlen = 0;
+ /* 10.2.1.5.2 step 4.2 */
+ if (drbg_kcapi_sym(drbg, drbg->C, drbg->scratchpad, &data)) {
+ len = 0;
+ goto out;
+ }
+ outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
+ drbg_blocklen(drbg) : (buflen - len);
+ if (!drbg_fips_continuous_test(drbg, drbg->scratchpad)) {
+ /* 10.2.1.5.2 step 6 */
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ continue;
+ }
+ /* 10.2.1.5.2 step 4.3 */
+ memcpy(buf + len, drbg->scratchpad, outlen);
+ len += outlen;
+ /* 10.2.1.5.2 step 6 */
+ if (len < buflen)
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ }
+
+ /* 10.2.1.5.2 step 6 */
+ /*TODO the DF function is called again since according to step
+ * 2, the "additional_input" after step 2 is the output of the DF
+ * function -- when we save the DF output as a replacement
+ * for the addtl_input data, we do not need to call the DF again here */
+ if (addtl)
+ addtl->next = NULL;
+ if (drbg_ctr_update(drbg, addtl, 1))
+ return 0;
+
+out:
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ return len;
+}
+
+static struct drbg_state_ops drbg_ctr_ops = {
+ .update = drbg_ctr_update,
+ .generate = drbg_ctr_generate,
+ .crypto_init = drbg_init_sym_kernel,
+ .crypto_fini = drbg_fini_sym_kernel,
+};
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+
+/******************************************************************
+ * HMAC DRBG callback functions
+ ******************************************************************/
+
+#if defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_HMAC)
+static int drbg_kcapi_hash(struct drbg_state *drbg, unsigned char *key,
+ unsigned char *outval, struct drbg_string *in);
+static int drbg_init_hash_kernel(struct drbg_state *drbg);
+static int drbg_fini_hash_kernel(struct drbg_state *drbg);
+#endif /* (CONFIG_CRYPTO_DRBG_HASH || CONFIG_CRYPTO_DRBG_HMAC) */
+
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+/* update function of HMAC DRBG as defined in 10.1.2.2 */
+static int drbg_hmac_update(struct drbg_state *drbg, struct drbg_string *seed,
+ int reseed)
+{
+ int ret = -EFAULT;
+ int i = 0;
+ struct drbg_string seed1, seed2, cipherin;
+
+ if (!reseed) {
+ /* 10.1.2.3 step 2 already implicitly covered with
+ * the initial memset(0) of drbg->C */
+ memset(drbg->C, 0, drbg_statelen(drbg));
+ memset(drbg->V, 1, drbg_statelen(drbg));
+ }
+
+ /* build linked list which implements the concatenation and fill
+ * first part*/
+ drbg_string_fill(&seed1, drbg->V, drbg_statelen(drbg));
+ /* buffer will be filled in for loop below with one byte */
+ drbg_string_fill(&seed2, NULL, 1);
+ seed1.next = &seed2;
+ /* seed may be NULL */
+ seed2.next = seed;
+
+ drbg_string_fill(&cipherin, drbg->V, drbg_statelen(drbg));
+ /* we execute two rounds of V/K massaging */
+ for (i = 2; 0 < i; i--) {
+ /* first round uses 0x0, second 0x1 */
+ unsigned char prefix = DRBG_PREFIX0;
+ if (1 == i)
+ prefix = DRBG_PREFIX1;
+ /* 10.1.2.2 step 1 and 4 -- concatenation and HMAC for key */
+ seed2.buf = &prefix;
+ ret = drbg_kcapi_hash(drbg, drbg->C, drbg->C, &seed1);
+ if (ret)
+ return ret;
+
+ /* 10.1.2.2 step 2 and 5 -- HMAC for V */
+ ret = drbg_kcapi_hash(drbg, drbg->C, drbg->V, &cipherin);
+ if (ret)
+ return ret;
+
+ /* 10.1.2.2 step 3 */
+ if (!seed || 0 == seed->len)
+ return ret;
+ }
+
+ return 0;
+}
+
+/* generate function of HMAC DRBG as defined in 10.1.2.5 */
+static unsigned int drbg_hmac_generate(struct drbg_state *drbg,
+ unsigned char *buf,
+ unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ unsigned int len = 0;
+ struct drbg_string data;
+
+ /* 10.1.2.5 step 2 */
+ if (addtl && 0 < addtl->len) {
+ addtl->next = NULL;
+ if (drbg_hmac_update(drbg, addtl, 1))
+ return 0;
+ }
+
+ drbg_string_fill(&data, drbg->V, drbg_statelen(drbg));
+ while (len < buflen) {
+ unsigned int outlen = 0;
+ /* 10.1.2.5 step 4.1 */
+ if (drbg_kcapi_hash(drbg, drbg->C, drbg->V, &data))
+ return 0;
+ outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
+ drbg_blocklen(drbg) : (buflen - len);
+ if (!drbg_fips_continuous_test(drbg, drbg->V))
+ continue;
+
+ /* 10.1.2.5 step 4.2 */
+ memcpy(buf + len, drbg->V, outlen);
+ len += outlen;
+ }
+
+ /* 10.1.2.5 step 6 */
+ if (addtl)
+ addtl->next = NULL;
+ if (drbg_hmac_update(drbg, addtl, 1))
+ return 0;
+
+ return len;
+}
+
+static struct drbg_state_ops drbg_hmac_ops = {
+ .update = drbg_hmac_update,
+ .generate = drbg_hmac_generate,
+ .crypto_init = drbg_init_hash_kernel,
+ .crypto_fini = drbg_fini_hash_kernel,
+
+};
+#endif /* CONFIG_CRYPTO_DRBG_HMAC */
+
+/******************************************************************
+ * Hash DRBG callback functions
+ ******************************************************************/
+
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+/*
+ * scratchpad usage: as drbg_hash_update and drbg_hash_df are used
+ * interlinked, the scratchpad is used as follows:
+ * drbg_hash_update
+ * start: drbg->scratchpad
+ * length: drbg_statelen(drbg)
+ * drbg_hash_df:
+ * start: drbg->scratchpad + drbg_statelen(drbg)
+ * length: drbg_blocklen(drbg)
+ */
+/* Derivation Function for Hash DRBG as defined in 10.4.1 */
+static int drbg_hash_df(struct drbg_state *drbg,
+ unsigned char *outval, size_t outlen,
+ struct drbg_string *entropy)
+{
+ int ret = 0;
+ size_t len = 0;
+ unsigned char input[5];
+ unsigned char *tmp = drbg->scratchpad + drbg_statelen(drbg);
+ struct drbg_string data1;
+
+ memset(tmp, 0, drbg_blocklen(drbg));
+
+ /* 10.4.1 step 3 */
+ input[0] = 1;
+ drbg_int2byte(&input[1], (outlen * 8), 4);
+
+ /* 10.4.1 step 4.1 -- concatenation of data for input into hash */
+ drbg_string_fill(&data1, input, 5);
+ data1.next = entropy;
+
+ /* 10.4.1 step 4 */
+ while (len < outlen) {
+ short blocklen = 0;
+ /* 10.4.1 step 4.1 */
+ ret = drbg_kcapi_hash(drbg, NULL, tmp, &data1);
+ if (ret)
+ goto out;
+ /* 10.4.1 step 4.2 */
+ input[0]++;
+ blocklen = (drbg_blocklen(drbg) < (outlen - len)) ?
+ drbg_blocklen(drbg) : (outlen - len);
+ memcpy(outval + len, tmp, blocklen);
+ len += blocklen;
+ }
+
+out:
+ memset(tmp, 0, drbg_blocklen(drbg));
+ return ret;
+}
+
+/* update function for Hash DRBG as defined in 10.1.1.2 / 10.1.1.3 */
+static int drbg_hash_update(struct drbg_state *drbg, struct drbg_string *seed,
+ int reseed)
+{
+ int ret = 0;
+ struct drbg_string data1, data2;
+ unsigned char *V = drbg->scratchpad;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ memset(drbg->scratchpad, 0, drbg_statelen(drbg));
+ if (!seed)
+ return -EINVAL;
+
+ if (reseed) {
+ /* 10.1.1.3 step 1: string length is concatenation of
+ * 1 byte, V and seed (which is concatenated entropy/addtl
+ * input)
+ */
+ memcpy(V, drbg->V, drbg_statelen(drbg));
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, V, drbg_statelen(drbg));
+ data1.next = &data2;
+ data2.next = seed;
+ } else {
+ drbg_string_fill(&data1, seed->buf, seed->len);
+ data1.next = seed->next;
+ }
+
+ /* 10.1.1.2 / 10.1.1.3 step 2 and 3 */
+ ret = drbg_hash_df(drbg, drbg->V, drbg_statelen(drbg), &data1);
+ if (ret)
+ goto out;
+
+ /* 10.1.1.2 / 10.1.1.3 step 4 -- concatenation */
+ prefix = DRBG_PREFIX0;
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, drbg->V, drbg_statelen(drbg));
+ data1.next = &data2;
+ /* 10.1.1.2 / 10.1.1.3 step 4 -- df operation */
+ ret = drbg_hash_df(drbg, drbg->C, drbg_statelen(drbg), &data1);
+
+out:
+ memset(drbg->scratchpad, 0, drbg_statelen(drbg));
+ return ret;
+}
+
+/* processing of additional information string for Hash DRBG */
+static int drbg_hash_process_addtl(struct drbg_state *drbg,
+ struct drbg_string *addtl)
+{
+ int ret = 0;
+ struct drbg_string data1, data2;
+ struct drbg_string *data3;
+ unsigned char prefix = DRBG_PREFIX2;
+
+ /* this is value w as per documentation */
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+
+ /* 10.1.1.4 step 2 */
+ if (!addtl || 0 == addtl->len)
+ return 0;
+
+ /* 10.1.1.4 step 2a -- concatenation */
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, drbg->V, drbg_statelen(drbg));
+ data3 = addtl;
+ data1.next = &data2;
+ data2.next = data3;
+ data3->next = NULL;
+ /* 10.1.1.4 step 2a -- cipher invocation */
+ ret = drbg_kcapi_hash(drbg, NULL, drbg->scratchpad, &data1);
+ if (ret)
+ goto out;
+
+ /* 10.1.1.4 step 2b */
+ drbg_add_buf(drbg->V, drbg_statelen(drbg),
+ drbg->scratchpad, drbg_blocklen(drbg));
+
+out:
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ return ret;
+}
+
+/*
+ * Hashgen defined in 10.1.1.4
+ */
+static unsigned int drbg_hash_hashgen(struct drbg_state *drbg,
+ unsigned char *buf,
+ unsigned int buflen)
+{
+ unsigned int len = 0;
+ unsigned char *src = drbg->scratchpad;
+ unsigned char *dst = drbg->scratchpad + drbg_statelen(drbg);
+ struct drbg_string data;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ /* use the scratchpad as a lookaside buffer */
+ memset(src, 0, drbg_statelen(drbg));
+ memset(dst, 0, drbg_blocklen(drbg));
+
+ /* 10.1.1.4 step hashgen 2 */
+ memcpy(src, drbg->V, drbg_statelen(drbg));
+
+ drbg_string_fill(&data, src, drbg_statelen(drbg));
+ while (len < buflen) {
+ unsigned int outlen = 0;
+ /* 10.1.1.4 step hashgen 4.1 */
+ if (drbg_kcapi_hash(drbg, NULL, dst, &data)) {
+ len = 0;
+ goto out;
+ }
+ outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
+ drbg_blocklen(drbg) : (buflen - len);
+ if (!drbg_fips_continuous_test(drbg, dst)) {
+ drbg_add_buf(src, drbg_statelen(drbg), &prefix, 1);
+ continue;
+ }
+ /* 10.1.1.4 step hashgen 4.2 */
+ memcpy(buf + len, dst, outlen);
+ len += outlen;
+ /* 10.1.1.4 hashgen step 4.3 */
+ if (len < buflen)
+ drbg_add_buf(src, drbg_statelen(drbg), &prefix, 1);
+ }
+
+out:
+ memset(drbg->scratchpad, 0,
+ (drbg_statelen(drbg) + drbg_blocklen(drbg)));
+ return len;
+}
+
+/* generate function for Hash DRBG as defined in 10.1.1.4 */
+static unsigned int drbg_hash_generate(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ unsigned int len = 0;
+ unsigned char req[8];
+ unsigned char prefix = DRBG_PREFIX3;
+ struct drbg_string data1, data2;
+
+ /*
+ * scratchpad usage: drbg_hash_process_addtl uses the scratchpad, but
+ * fully completes before returning. Thus, we can reuse the scratchpad
+ */
+ /* 10.1.1.4 step 2 */
+ if (drbg_hash_process_addtl(drbg, addtl))
+ return 0;
+ /* 10.1.1.4 step 3 -- invocation of the Hashgen function defined in
+ * 10.1.1.4 */
+ len = drbg_hash_hashgen(drbg, buf, buflen);
+
+ /* this is the value H as documented in 10.1.1.4 */
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ /* 10.1.1.4 step 4 */
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, drbg->V, drbg_statelen(drbg));
+ data1.next = &data2;
+ if (drbg_kcapi_hash(drbg, NULL, drbg->scratchpad, &data1)) {
+ len = 0;
+ goto out;
+ }
+
+ /* 10.1.1.4 step 5 */
+ drbg_add_buf(drbg->V, drbg_statelen(drbg),
+ drbg->scratchpad, drbg_blocklen(drbg));
+ drbg_add_buf(drbg->V, drbg_statelen(drbg),
+ drbg->C, drbg_statelen(drbg));
+ drbg_int2byte(req, drbg->reseed_ctr, sizeof(req));
+ drbg_add_buf(drbg->V, drbg_statelen(drbg), req, 8);
+
+out:
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ return len;
+}
+
+/*
+ * scratchpad usage: as update and generate are used isolated, both
+ * can use the scratchpad
+ */
+static struct drbg_state_ops drbg_hash_ops = {
+ .update = drbg_hash_update,
+ .generate = drbg_hash_generate,
+ .crypto_init = drbg_init_hash_kernel,
+ .crypto_fini = drbg_fini_hash_kernel,
+};
+#endif /* CONFIG_CRYPTO_DRBG_HASH */
+
+/******************************************************************
+ * Functions common for DRBG implementations
+ ******************************************************************/
+
+/*
+ * Seeding or reseeding of the DRBG
+ *
+ * @drbg: DRBG state struct
+ * @pers: personalization / additional information buffer
+ * @reseed: 0 for initial seed process, 1 for reseeding
+ *
+ * return:
+ * 0 on success
+ * error value otherwise
+ */
+static int drbg_seed(struct drbg_state *drbg, struct drbg_string *pers,
+ bool reseed)
+{
+ int ret = 0;
+ unsigned char *entropy = NULL;
+ size_t entropylen = 0;
+ struct drbg_string data1;
+ struct drbg_string *data2;
+
+ /* 9.1 / 9.2 / 9.3.1 step 3 */
+ if (pers && pers->len > (drbg_max_addtl(drbg))) {
+ pr_devel("DRBG: personalization string too long %lu\n",
+ pers->len);
+ return -EINVAL;
+ }
+
+ if (drbg->test_data && drbg->test_data->testentropy) {
+ drbg_string_fill(&data1, drbg->test_data->testentropy->buf,
+ drbg->test_data->testentropy->len);
+ pr_devel("DRBG: using test entropy\n");
+ } else {
+ /* Gather entropy equal to the security strength of the DRBG.
+ * With a derivation function, a nonce is required in addition
+ * to the entropy. A nonce must be at least 1/2 of the security
+ * strength of the DRBG in size. Thus, entropy * nonce is 3/2
+ * of the strength. The consideration of a nonce is only
+ * applicable during initial seeding. */
+ entropylen = drbg_sec_strength(drbg->core->flags);
+ if (!entropylen)
+ return -EFAULT;
+ if (!reseed)
+ /* make sure we round up strength/2 in
+ * case it is not divisible by 2 */
+ entropylen = ((entropylen + 1) / 2) * 3;
+ pr_devel("DRBG: (re)seeding with %zu bytes of entropy\n",
+ entropylen);
+ entropy = kzalloc(entropylen, GFP_KERNEL);
+ if (!entropy)
+ return -ENOMEM;
+ get_random_bytes(entropy, entropylen);
+ drbg_string_fill(&data1, entropy, entropylen);
+ }
+
+ /* concatenation of entropy with personalization str / addtl input) */
+ if (pers && 0 < pers->len) {
+ data2 = pers;
+ data2->next = NULL;
+ data1.next = data2;
+ pr_devel("DRBG: using personalization string\n");
+ }
+
+ ret = drbg->d_ops->update(drbg, &data1, reseed);
+ if (ret)
+ goto out;
+
+ drbg->seeded = true;
+ /* 10.1.1.2 / 10.1.1.3 step 5 */
+ drbg->reseed_ctr = 1;
+
+out:
+ if (entropy)
+ kzfree(entropy);
+ return ret;
+}
+
+/*
+ * Free all substructures in a DRBG state without the DRBG state structure
+ */
+static inline void drbg_dealloc_state(struct drbg_state *drbg)
+{
+ if (!drbg)
+ return;
+ if (drbg->V)
+ kzfree(drbg->V);
+ drbg->V = NULL;
+ if (drbg->C)
+ kzfree(drbg->C);
+ drbg->C = NULL;
+ if (drbg->scratchpad)
+ kzfree(drbg->scratchpad);
+ drbg->scratchpad = NULL;
+ drbg->reseed_ctr = 0;
+#ifdef CONFIG_CRYPTO_FIPS
+ if (drbg->prev)
+ kzfree(drbg->prev);
+ drbg->prev = NULL;
+ drbg->fips_primed = false;
+#endif
+}
+
+/*
+ * Allocate all sub-structures for a DRBG state
+ * The DRBG state structure must already be allocated
+ */
+static inline int drbg_alloc_state(struct drbg_state *drbg)
+{
+ int ret = -ENOMEM;
+ unsigned int sb_size = 0;
+
+ if (!drbg)
+ return -EINVAL;
+
+ drbg->V = kzalloc(drbg_statelen(drbg), GFP_KERNEL);
+ if (!drbg->V)
+ goto err;
+ drbg->C = kzalloc(drbg_statelen(drbg), GFP_KERNEL);
+ if (!drbg->C)
+ goto err;
+#ifdef CONFIG_CRYPTO_FIPS
+ drbg->prev = kzalloc(drbg_blocklen(drbg), GFP_KERNEL);
+ if (!drbg->prev)
+ goto err;
+ drbg->fips_primed = false;
+#endif
+ /* scratchpad is only generated for CTR and Hash */
+ if (drbg->core->flags & DRBG_HMAC)
+ sb_size = 0;
+ else if (drbg->core->flags & DRBG_CTR)
+ sb_size = drbg_statelen(drbg) + drbg_blocklen(drbg) + /* temp */
+ drbg_statelen(drbg) + /* df_data */
+ drbg_blocklen(drbg) + /* pad */
+ drbg_blocklen(drbg) + /* iv */
+ drbg_statelen(drbg); /* temp */
+ else
+ sb_size = drbg_statelen(drbg) + drbg_blocklen(drbg);
+
+ if (0 < sb_size) {
+ drbg->scratchpad = kzalloc(sb_size, GFP_KERNEL);
+ if (!drbg->scratchpad)
+ goto err;
+ }
+ spin_lock_init(&drbg->drbg_lock);
+ return 0;
+
+err:
+ drbg_dealloc_state(drbg);
+ return ret;
+}
+
+/*
+ * Strategy to avoid holding long term locks: generate a shadow copy of DRBG
+ * and perform all operations on this shadow copy. After finishing, restore
+ * the updated state of the shadow copy into original drbg state. This way,
+ * only the read and write operations of the original drbg state must be
+ * locked
+ */
+
+/*
+ * Copy the DRBG state
+ */
+static inline void drbg_copy_drbg(struct drbg_state *src,
+ struct drbg_state *dst)
+{
+ if (!src || !dst)
+ return;
+ memcpy(dst->V, src->V, drbg_statelen(src));
+ memcpy(dst->C, src->C, drbg_statelen(src));
+ dst->reseed_ctr = src->reseed_ctr;
+ /* no copy of scratchpad */
+ /* priv_data is initialized with call to crypto_init */
+ /* d_ops are set outside, as the struct is const */
+ dst->seeded = src->seeded;
+ dst->pr = src->pr;
+#ifdef CONFIG_CRYPTO_FIPS
+ dst->fips_primed = src->fips_primed;
+ memcpy(dst->prev, src->prev, drbg_blocklen(src));
+#endif
+ /* test_data is set outside, as the struct is const */
+}
+/*
+ * Generate shadow copy of the DRBG state
+ */
+static int drbg_make_shadow(struct drbg_state *drbg, struct drbg_state **shadow)
+{
+ int ret = -ENOMEM;
+ struct drbg_state *tmp = NULL;
+
+ /* some sanity checks */
+ if (!drbg || !drbg->core || !drbg->V || !drbg->C) {
+ pr_devel("DRBG: attempt to generate shadow copy for "
+ "uninitialized DRBG state rejected\n");
+ return -EINVAL;
+ }
+ /* HMAC does not have a scratchpad */
+ if (!(drbg->core->flags & DRBG_HMAC) && NULL == drbg->scratchpad)
+ return -EINVAL;
+
+ tmp = kzalloc(sizeof(struct drbg_state), GFP_KERNEL);
+ if (!tmp)
+ return -ENOMEM;
+ /* read-only data */
+ tmp->core = drbg->core;
+
+ ret = drbg_alloc_state(tmp);
+ if (ret)
+ goto err;
+
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg_copy_drbg(drbg, tmp);
+ tmp->d_ops = drbg->d_ops;
+ /* only make a link to the test buffer, as we only read that data */
+ tmp->test_data = drbg->test_data;
+ spin_unlock_bh(&drbg->drbg_lock);
+ *shadow = tmp;
+ return 0;
+
+err:
+ if (tmp)
+ kzfree(tmp);
+ return ret;
+}
+
+/*
+ * Restore shadow state into original DRBG state
+ */
+static void drbg_restore_shadow(struct drbg_state *drbg,
+ struct drbg_state **shadow)
+{
+ struct drbg_state *tmp = *shadow;
+
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg_copy_drbg(tmp, drbg);
+ spin_unlock_bh(&drbg->drbg_lock);
+ drbg_dealloc_state(tmp);
+ kzfree(tmp);
+ *shadow = NULL;
+}
+
+/*************************************************************************
+ * DRBG interface functions
+ *************************************************************************/
+
+/*
+ * DRBG generate function as required by SP800-90A - this function
+ * generates random numbers
+ *
+ * @drbg DRBG state handle
+ * @buf Buffer where to store the random numbers -- the buffer must already
+ * be pre-allocated by caller
+ * @buflen Length of output buffer - this value defines the number of random
+ * bytes pulled from DRBG
+ * @addtl Additional input that is mixed into state, may be NULL -- note
+ * the entropy is pulled by the DRBG internally unconditionally
+ * as defined in SP800-90A. The additional input is mixed into
+ * the state in addition to the pulled entropy.
+ *
+ * return: generated number of bytes
+ */
+static unsigned int drbg_generate(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ unsigned int len = 0;
+ struct drbg_state *shadow = NULL;
+
+ if (0 == buflen || !buf) {
+ pr_devel("DRBG: no buffer provided\n");
+ return 0;
+ }
+ if (addtl && NULL == addtl->buf && 0 < addtl->len) {
+ pr_devel("DRBG: wrong format of additional information\n");
+ return 0;
+ }
+
+ if (drbg_make_shadow(drbg, &shadow)) {
+ pr_devel("DRBG: shadow copy cannot be generated\n");
+ return 0;
+ }
+ /* 9.3.1 step 2 */
+ if (buflen > (drbg_max_request_bytes(shadow))) {
+ pr_devel("DRBG: requested random numbers too large %u\n",
+ buflen);
+ goto err;
+ }
+ /* 9.3.1 step 3 is implicit with the chosen DRBG */
+ /* 9.3.1 step 4 */
+ if (addtl && addtl->len > (drbg_max_addtl(shadow))) {
+ pr_devel("DRBG: additional information string too long %zu\n",
+ addtl->len);
+ goto err;
+ }
+ /* 9.3.1 step 5 is implicit with the chosen DRBG */
+ /* 9.3.1 step 6 and 9 supplemented by 9.3.2 step c -- the spec is a
+ * bit convoluted here, we make it simpler */
+ if ((drbg_max_requests(shadow)) < shadow->reseed_ctr)
+ shadow->seeded = false;
+
+ /* allocate cipher handle */
+ if (shadow->d_ops->crypto_init && shadow->d_ops->crypto_init(shadow))
+ goto err;
+
+ if (shadow->pr || !shadow->seeded) {
+ pr_devel("DRBG: reseeding before generation (prediction "
+ "resistance: %s, state %s)\n",
+ drbg->pr ? "true" : "false",
+ drbg->seeded ? "seeded" : "unseeded");
+ /* 9.3.1 steps 7.1 through 7.3 */
+ if (drbg_seed(shadow, addtl, true))
+ goto err;
+ /* 9.3.1 step 7.4 */
+ addtl = NULL;
+ }
+ /* 9.3.1 step 8 and 10 */
+ len = shadow->d_ops->generate(shadow, buf, buflen, addtl);
+
+ /* 10.1.1.4 step 6, 10.1.2.5 step 7, 10.2.1.5.2 step 7 */
+ shadow->reseed_ctr++;
+
+ /* 11.3.3 -- re-perform self tests after some generated random
+ * numbers, the chosen value after which self test is performed
+ * is arbitrary, but it should be reasonable */
+ /* Here we do not perform the self tests because of the following
+ * reasons: it is mathematically impossible that the initial self tests
+ * were successfully and the following are not. If the initial would
+ * pass and the following would not, the kernel integrity is violated.
+ * In this case, the entire kernel operation is questionable and it
+ * is unlikely that the integrity violation only affects to the
+ * correct operation of the DRBG.
+ */
+#if 0
+ if (shadow->reseed_ctr && !(shadow->reseed_ctr % 4096)) {
+ int err = 0;
+ pr_devel("DRBG: start to perform self test\n");
+ if (drbg->core->flags & DRBG_HMAC)
+ err = alg_test("drbg(pr(hmac(sha256)))",
+ "drbg(pr(hmac(sha256)))", 0, 0);
+ else if (drbg->core->flags & DRBG_CTR)
+ err = alg_test("drbg(pr(ctr(aes128)))",
+ "drbg(pr(ctr(aes128)))", 0, 0);
+ else
+ err = alg_test("drbg(pr(sha256))",
+ "drbg(pr(sha256))", 0, 0);
+ if (err) {
+ pr_err("DRBG: periodical self test failed\n");
+ /* uninstantiate implies that from now on, only errors
+ * are returned when reusing this DRBG cipher handle */
+ drbg_uninstantiate(drbg);
+ drbg_dealloc_state(shadow);
+ kzfree(shadow);
+ return 0;
+ } else {
+ pr_devel("DRBG: self test successful\n");
+ }
+ }
+#endif
+
+err:
+ if (shadow->d_ops->crypto_fini)
+ shadow->d_ops->crypto_fini(shadow);
+ drbg_restore_shadow(drbg, &shadow);
+ return len;
+}
+
+/*
+ * Wrapper around drbg_generate which can pull arbitrary long strings
+ * from the DRBG without hitting the maximum request limitation.
+ *
+ * Parameters: see drbg_generate
+ * Return codes: see drbg_generate -- if one drbg_generate request fails,
+ * the entire drbg_generate_long request fails
+ */
+static unsigned int drbg_generate_long(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ unsigned int len = 0;
+ unsigned int slice = 0;
+ do {
+ unsigned int tmplen = 0;
+ unsigned int chunk = 0;
+ slice = ((buflen - len) / drbg_max_request_bytes(drbg));
+ chunk = slice ? drbg_max_request_bytes(drbg) : (buflen - len);
+ tmplen = drbg_generate(drbg, buf + len, chunk, addtl);
+ if (!tmplen)
+ return 0;
+ len += tmplen;
+ } while (slice > 0);
+ return len;
+}
+
+/*
+ * DRBG instantiation function as required by SP800-90A - this function
+ * sets up the DRBG handle, performs the initial seeding and all sanity
+ * checks required by SP800-90A
+ *
+ * @drbg memory of state -- if NULL, new memory is allocated
+ * @pers Personalization string that is mixed into state, may be NULL -- note
+ * the entropy is pulled by the DRBG internally unconditionally
+ * as defined in SP800-90A. The additional input is mixed into
+ * the state in addition to the pulled entropy.
+ * @coreref reference to core
+ * @pr prediction resistance enabled
+ *
+ * return
+ * 0 on success
+ * error value otherwise
+ */
+static int drbg_instantiate(struct drbg_state *drbg, struct drbg_string *pers,
+ int coreref, bool pr)
+{
+ int ret = -ENOMEM;
+
+ pr_devel("DRBG: Initializing DRBG core %d with prediction resistance "
+ "%s\n", coreref, pr ? "enabled" : "disabled");
+ drbg->core = &cores[coreref];
+ drbg->pr = pr;
+ drbg->seeded = false;
+ switch (drbg->core->flags & DRBG_TYPE_MASK) {
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+ case DRBG_HMAC:
+ drbg->d_ops = &drbg_hmac_ops;
+ break;
+#endif /* CONFIG_CRYPTO_DRBG_HMAC */
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+ case DRBG_HASH:
+ drbg->d_ops = &drbg_hash_ops;
+ break;
+#endif /* CONFIG_CRYPTO_DRBG_HASH */
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+ case DRBG_CTR:
+ drbg->d_ops = &drbg_ctr_ops;
+ break;
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ /* 9.1 step 1 is implicit with the selected DRBG type -- see
+ * drbg_sec_strength() */
+
+ /* 9.1 step 2 is implicit as caller can select prediction resistance
+ * and the flag is copied into drbg->flags --
+ * all DRBG types support prediction resistance */
+
+ /* 9.1 step 4 is implicit in drbg_sec_strength */
+
+ /* no allocation of drbg as this is done by the kernel crypto API */
+ ret = drbg_alloc_state(drbg);
+ if (ret)
+ return ret;
+
+ ret = -EFAULT;
+ /* allocate cipher handle */
+ if (drbg->d_ops->crypto_init && drbg->d_ops->crypto_init(drbg))
+ goto err;
+ /* 9.1 step 6 through 11 */
+ ret = drbg_seed(drbg, pers, false);
+ /* deallocate cipher handle */
+ if (drbg->d_ops->crypto_fini)
+ drbg->d_ops->crypto_fini(drbg);
+ if (ret)
+ goto err;
+
+ return 0;
+
+err:
+ drbg_dealloc_state(drbg);
+ return ret;
+}
+
+/*
+ * DRBG uninstantiate function as required by SP800-90A - this function
+ * frees all buffers and the DRBG handle
+ *
+ * @drbg DRBG state handle
+ *
+ * return
+ * 0 on success
+ */
+static int drbg_uninstantiate(struct drbg_state *drbg)
+{
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg_dealloc_state(drbg);
+ /* no scrubbing of test_data -- this shall survive an uninstantiate */
+ spin_unlock_bh(&drbg->drbg_lock);
+ /* no freeing of drbg as this is done by the kernel crypto API */
+ return 0;
+}
+
+/*
+ * Helper function for setting the test data in the DRBG
+ *
+ * @drbg DRBG state handle
+ * @test_data test data to sets
+ */
+static inline void drbg_set_testdata(struct drbg_state *drbg,
+ struct drbg_test_data *test_data)
+{
+ if (!test_data || !test_data->testentropy)
+ return;
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg->test_data = test_data;
+ spin_unlock_bh(&drbg->drbg_lock);
+}
+
+/***************************************************************
+ * Kernel crypto APi cipher invocations requested by DRBG
+ ***************************************************************/
+
+#if defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_HMAC)
+struct sdesc {
+ struct shash_desc shash;
+ char ctx[];
+};
+
+static int drbg_init_hash_kernel(struct drbg_state *drbg)
+{
+ struct sdesc *sdesc;
+ struct crypto_shash *tfm;
+
+ tfm = crypto_alloc_shash(drbg->core->backend_cra_name, 0, 0);
+ if (IS_ERR(tfm)) {
+ pr_info("drbg: could not allocate digest TFM handle\n");
+ return PTR_ERR(tfm);
+ }
+ BUG_ON(drbg_blocklen(drbg) != crypto_shash_digestsize(tfm));
+ sdesc = kzalloc(sizeof(struct shash_desc) + crypto_shash_descsize(tfm),
+ GFP_KERNEL);
+ if (!sdesc) {
+ crypto_free_shash(tfm);
+ return -ENOMEM;
+ }
+
+ sdesc->shash.tfm = tfm;
+ sdesc->shash.flags = 0;
+ drbg->priv_data = sdesc;
+ return 0;
+}
+
+static int drbg_fini_hash_kernel(struct drbg_state *drbg)
+{
+ struct sdesc *sdesc = (struct sdesc *)drbg->priv_data;
+ if (sdesc) {
+ crypto_free_shash(sdesc->shash.tfm);
+ kzfree(sdesc);
+ }
+ drbg->priv_data = NULL;
+ return 0;
+}
+
+static int drbg_kcapi_hash(struct drbg_state *drbg, unsigned char *key,
+ unsigned char *outval, struct drbg_string *in)
+{
+ struct sdesc *sdesc = (struct sdesc *)drbg->priv_data;
+
+ if (key)
+ crypto_shash_setkey(sdesc->shash.tfm, key, drbg_statelen(drbg));
+ crypto_shash_init(&sdesc->shash);
+ for (; NULL != in; in = in->next)
+ crypto_shash_update(&sdesc->shash, in->buf, in->len);
+ return crypto_shash_final(&sdesc->shash, outval);
+}
+#endif /* (CONFIG_CRYPTO_DRBG_HASH || CONFIG_CRYPTO_DRBG_HMAC) */
+
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+static int drbg_init_sym_kernel(struct drbg_state *drbg)
+{
+ int ret = 0;
+ struct crypto_blkcipher *tfm;
+
+ tfm = crypto_alloc_blkcipher(drbg->core->backend_cra_name, 0, 0);
+ if (IS_ERR(tfm)) {
+ pr_info("drbg: could not allocate cipher TFM handle\n");
+ return PTR_ERR(tfm);
+ }
+ drbg->priv_data = tfm;
+ return ret;
+}
+
+static int drbg_fini_sym_kernel(struct drbg_state *drbg)
+{
+ struct crypto_blkcipher *tfm =
+ (struct crypto_blkcipher *)drbg->priv_data;
+ if (tfm)
+ crypto_free_blkcipher(tfm);
+ drbg->priv_data = NULL;
+ return 0;
+}
+
+static int drbg_kcapi_sym(struct drbg_state *drbg, unsigned char *key,
+ unsigned char *outval, struct drbg_string *in)
+{
+ int ret = 0;
+ struct scatterlist sg_in, sg_out;
+ struct blkcipher_desc desc;
+ struct crypto_blkcipher *tfm =
+ (struct crypto_blkcipher *)drbg->priv_data;
+
+ desc.tfm = tfm;
+ desc.flags = 0;
+ crypto_blkcipher_setkey(tfm, key, (drbg_keylen(drbg)));
+ /* in is only component */
+ sg_init_one(&sg_in, in->buf, in->len);
+ sg_init_one(&sg_out, outval, drbg_blocklen(drbg));
+ ret = crypto_blkcipher_encrypt(&desc, &sg_out, &sg_in, in->len);
+
+ return ret;
+}
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+
+/***************************************************************
+ * Kernel crypto API interface to register DRBG
+ ***************************************************************/
+
+/*
+ * Look up the DRBG flags by given kernel crypto API cra_name
+ * The code uses the cores definition to do this
+ *
+ * @cra_name kernel crypto API cra_name
+ * @coreref reference to integer which is filled with the pointer to
+ * the applicable core
+ * @pr reference for setting prediction resistance
+ *
+ * return: flags
+ */
+static inline void drbg_convert_tfm_core(const char *cra_name,
+ int *coreref, bool *pr)
+{
+ int i = 0;
+ size_t start = 0;
+ int len = 0;
+
+ *pr = true;
+ /* disassemble the names */
+ if (0 == memcmp(cra_name, "drbg(nopr(", 10)) {
+ start = 10;
+ *pr = false;
+ } else if (0 == memcmp(cra_name, "drbg(pr(", 8)) {
+ start = 8;
+ } else {
+ return;
+ }
+
+ /* remove the first part and the closing parenthesis */
+ len = strlen(cra_name) - start - 2;
+ for (i = 0; ARRAY_SIZE(cores) > i; i++) {
+ if (0 == memcmp(cra_name + start, cores[i].cra_name, len)) {
+ *coreref = i;
+ return;
+ }
+ }
+}
+
+/*
+ * Initialize one DRBG invoked by the kernel crypto API
+ *
+ * Function uses the kernel crypto API cra_name to look up
+ * the flags to instantiate the DRBG
+ */
+static int drbg_kcapi_init(struct crypto_tfm *tfm)
+{
+ struct drbg_state *drbg = crypto_tfm_ctx(tfm);
+ bool pr = false;
+ int coreref = 0;
+
+ drbg_convert_tfm_core(crypto_tfm_alg_name(tfm), &coreref, &pr);
+ /* when personalization string is needed, the caller must call reset
+ * and provide the personalization string as seed information */
+ return drbg_instantiate(drbg, NULL, coreref, pr);
+}
+
+static void drbg_kcapi_cleanup(struct crypto_tfm *tfm)
+{
+ drbg_uninstantiate(crypto_tfm_ctx(tfm));
+}
+
+/*
+ * Generate random numbers invoked by the kernel crypto API:
+ * The API of the kernel crypto API is extended as follows:
+ *
+ * If dlen is larger than zero, rdata is interpreted as the output buffer
+ * where random data is to be stored.
+ *
+ * If dlen is zero, rdata is interpreted as a pointer to a struct drbg_gen
+ * which holds the additional information string that is used for the
+ * DRBG generation process. The output buffer that is to be used to store
+ * data is also pointed to by struct drbg_gen.
+ *
+ */
+static int drbg_kcapi_random(struct crypto_rng *tfm, u8 *rdata,
+ unsigned int dlen)
+{
+ struct drbg_state *drbg = crypto_rng_ctx(tfm);
+ if (0 < dlen) {
+ return drbg_generate_long(drbg, rdata, dlen, NULL);
+ } else {
+ struct drbg_gen *data = (struct drbg_gen *)rdata;
+ /* catch NULL pointer */
+ if (!data)
+ return 0;
+ drbg_set_testdata(drbg, data->test_data);
+ return drbg_generate_long(drbg, data->outbuf, data->outlen,
+ data->addtl);
+ }
+}
+
+/*
+ * Reset the DRBG invoked by the kernel crypto API
+ * The reset implies a full re-initialization of the DRBG. Similar to the
+ * generate function of drbg_kcapi_random, this function extends the
+ * kernel crypto API interface with struct drbg_gen
+ */
+static int drbg_kcapi_reset(struct crypto_rng *tfm, u8 *seed, unsigned int slen)
+{
+ struct drbg_state *drbg = crypto_rng_ctx(tfm);
+ struct crypto_tfm *tfm_base = crypto_rng_tfm(tfm);
+ bool pr = false;
+ struct drbg_string seed_string;
+ int coreref = 0;
+
+ drbg_uninstantiate(drbg);
+ drbg_convert_tfm_core(crypto_tfm_alg_name(tfm_base), &coreref, &pr);
+ if (0 < slen) {
+ drbg_string_fill(&seed_string, seed, slen);
+ return drbg_instantiate(drbg, &seed_string, coreref, pr);
+ } else {
+ struct drbg_gen *data = (struct drbg_gen *)seed;
+ /* allow invocation of API call with NULL, 0 */
+ if (!data)
+ return drbg_instantiate(drbg, NULL, coreref, pr);
+ drbg_set_testdata(drbg, data->test_data);
+ return drbg_instantiate(drbg, data->addtl, coreref, pr);
+ }
+}
+
+/***************************************************************
+ * Kernel module: code to load the module
+ ***************************************************************/
+
+/*
+ * Tests as defined in 11.3.2 in addition to the cipher tests: testing
+ * of the error handling.
+ *
+ * Note, testing of failing seed source as defined in 11.3.2 is not applicable
+ * as seed source of get_random_bytes does not fail.
+ * Note, testing the reseed counter is not done as an automatic reseeding
+ * is performed in drbg_generate when the reseed counter is too large.
+ */
+static inline int __init drbg_healthcheck_sanity(void)
+{
+#ifdef CONFIG_CRYPTO_FIPS
+ unsigned int len = 0;
+#define OUTBUFLEN 16
+ unsigned char buf[OUTBUFLEN];
+ struct drbg_state *drbg = NULL;
+ int ret = -EFAULT;
+ int rc = -EFAULT;
+ bool pr = false;
+ int coreref = 0;
+ struct drbg_string addtl;
+ size_t max_addtllen, max_request_bytes;
+
+ /* only perform test in FIPS mode */
+ if (0 == fips_enabled)
+ return 0;
+
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+ drbg_convert_tfm_core("drbg(nopr(ctr(aes128)))", &coreref, &pr);
+#elif CONFIG_CRYPTO_DRBG_HASH
+ drbg_convert_tfm_core("drbg(nopr(sha256)", &coreref, &pr);
+#else
+ drbg_convert_tfm_core("drbg(nopr(hmac(sha256)))", &coreref, &pr);
+#endif
+
+ drbg = kzalloc(sizeof(struct drbg_state), GFP_KERNEL);
+ if (!drbg)
+ return -ENOMEM;
+
+ /* if the following tests fail, it is likely that there is a buffer
+ * overflow as buf is much smaller than the requested or provided
+ * string lengths -- in case the error handling does not succeed
+ * we may get an OOPS. And we want to get an OOPS as this is a
+ * grave bug */
+
+ /* get a valid instance of DRBG for following tests */
+ ret = drbg_instantiate(drbg, NULL, coreref, pr);
+ if (ret)
+ goto outbuf;
+ max_addtllen = drbg_max_addtl(drbg);
+ max_request_bytes = drbg_max_request_bytes(drbg);
+ drbg_string_fill(&addtl, buf, max_addtllen + 1);
+ /* overflow addtllen with additonal info string */
+ len = drbg_generate(drbg, buf, OUTBUFLEN, &addtl);
+ if (len)
+ goto outdrbg;
+ /* overflow max_bits */
+ len = drbg_generate(drbg, buf, (max_request_bytes + 1), NULL);
+ if (len)
+ goto outdrbg;
+ drbg_uninstantiate(drbg);
+
+ /* overflow max addtllen with personalization string */
+ ret = drbg_instantiate(drbg, &addtl, coreref, pr);
+ if (0 == ret)
+ goto outdrbg;
+ /* test uninstantated DRBG */
+ len = drbg_generate(drbg, buf, (max_request_bytes + 1), NULL);
+ if (!len)
+ /* all tests passed */
+ rc = 0;
+
+ pr_devel("DRBG: Sanity tests for failure code paths successfully "
+ "completed\n");
+outdrbg:
+ drbg_uninstantiate(drbg);
+outbuf:
+ kzfree(drbg);
+ return rc;
+#else /* CONFIG_CRYPTO_FIPS */
+ return 0;
+#endif /* CONFIG_CRYPTO_FIPS */
+}
+
+
+static struct crypto_alg drbg_algs[22];
+
+/*
+ * Fill the array drbg_algs used to register the different DRBGs
+ * with the kernel crypto API. To fill the array, the information
+ * from cores[] is used.
+ */
+static inline void __init drbg_fill_array(unsigned long i, unsigned long j,
+ int pr)
+{
+ int pos = 0;
+
+ memset(&drbg_algs[i], 0, sizeof(struct crypto_alg));
+ if (pr) {
+ memcpy(drbg_algs[i].cra_name, "drbg(pr(", 8);
+ memcpy(drbg_algs[i].cra_driver_name, "drbg_pr_", 8);
+ pos = 8;
+ } else {
+ memcpy(drbg_algs[i].cra_name, "drbg(nopr(", 10);
+ memcpy(drbg_algs[i].cra_driver_name, "drbg_nopr_", 10);
+ pos = 10;
+ }
+ memcpy(drbg_algs[i].cra_name + pos, cores[j].cra_name,
+ strlen(cores[j].cra_name));
+ memcpy(drbg_algs[i].cra_name + pos + strlen(cores[j].cra_name), "))",
+ 2);
+ memcpy(drbg_algs[i].cra_driver_name + pos,
+ cores[j].cra_driver_name, strlen(cores[j].cra_driver_name));
+ drbg_algs[i].cra_priority = 100;
+ drbg_algs[i].cra_flags = CRYPTO_ALG_TYPE_RNG;
+ drbg_algs[i].cra_ctxsize = sizeof(struct drbg_state);
+ drbg_algs[i].cra_type = &crypto_rng_type;
+ drbg_algs[i].cra_module = THIS_MODULE;
+ drbg_algs[i].cra_init = drbg_kcapi_init;
+ drbg_algs[i].cra_exit = drbg_kcapi_cleanup;
+ drbg_algs[i].cra_u.rng.rng_make_random = drbg_kcapi_random;
+ drbg_algs[i].cra_u.rng.rng_reset = drbg_kcapi_reset;
+ drbg_algs[i].cra_u.rng.seedsize = 0;
+}
+
+static int __init drbg_init(void)
+{
+ unsigned int i = 0; /* pointer to drbg_algs */
+ unsigned int j = 0; /* pointer to cores */
+ int ret = -EFAULT;
+
+ ret = drbg_healthcheck_sanity();
+ if (ret)
+ return ret;
+
+ if (ARRAY_SIZE(cores) * 2 > ARRAY_SIZE(drbg_algs))
+ pr_info("drbg: Not all available DRBGs registered"
+ "(slots needed: %lu, slots available: %lu)\n",
+ ARRAY_SIZE(cores) * 2, ARRAY_SIZE(drbg_algs));
+
+ /* each DRBG definition can be used with PR and without PR, thus
+ * we instantiate each DRBG in cores[] twice */
+ for (j = 0; ARRAY_SIZE(cores) > j; j++) {
+ drbg_fill_array(i, j, 1);
+ i++;
+ drbg_fill_array(i, j, 0);
+ i++;
+ }
+ return crypto_register_algs(drbg_algs, (ARRAY_SIZE(cores) * 2));
+}
+
+void __exit drbg_exit(void)
+{
+ crypto_unregister_algs(drbg_algs, (ARRAY_SIZE(cores) * 2));
+}
+
+module_init(drbg_init);
+module_exit(drbg_exit);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Stephan Mueller <smueller@chronox.de>");
+MODULE_DESCRIPTION("NIST SP800-90A Deterministic Random Bit Generator (DRBG) using following cores:"
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+"HMAC "
+#endif
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+"Hash "
+#endif
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+"CTR"
+#endif
+);
^ permalink raw reply related [flat|nested] 29+ messages in thread* [PATCH v4 1/6] SP800-90A Deterministic Random Bit Generator
2014-03-27 19:56 ` Stephan Mueller
@ 2014-04-11 18:07 ` Stephan Mueller
2014-04-11 18:20 ` Joe Perches
2014-04-15 5:35 ` [PATCH v5 " Stephan Mueller
0 siblings, 2 replies; 29+ messages in thread
From: Stephan Mueller @ 2014-04-11 18:07 UTC (permalink / raw)
To: linux-kernel, linux-crypto; +Cc: aquini, jeremy.wayne.powell, clemens, pwalten
Changes v4:
* change return codes of generate functions to signed int to convey error
codes and to match the kernel crypto API expecations on the generate
function.
* add BUG_ON throughout drbg_healthcheck_sanity() since any failure should
should be caugth to prevent the DRBG from operating
* change layout of debugging printk
Signed-off-by: Stephan Mueller <smueller@chronox.de>
---
create mode 100644 crypto/drbg.c
diff --git a/crypto/drbg.c b/crypto/drbg.c
new file mode 100644
index 0000000..98e3fe3
--- /dev/null
+++ b/crypto/drbg.c
@@ -0,0 +1,1997 @@
+/*
+ * DRBG: Deterministic Random Bits Generator
+ * Based on NIST Recommended DRBG from NIST SP800-90A with the following
+ * properties:
+ * * CTR DRBG with DF with AES-128, AES-192, AES-256 cores
+ * * Hash DRBG with DF with SHA-1, SHA-256, SHA-384, SHA-512 cores
+ * * HMAC DRBG with DF with SHA-1, SHA-256, SHA-384, SHA-512 cores
+ * * with and without prediction resistance
+ *
+ * Copyright Stephan Mueller <smueller@chronox.de>, 2014
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, and the entire permission notice in its entirety,
+ * including the disclaimer of warranties.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote
+ * products derived from this software without specific prior
+ * written permission.
+ *
+ * ALTERNATIVELY, this product may be distributed under the terms of
+ * the GNU General Public License, in which case the provisions of the GPL are
+ * required INSTEAD OF the above restrictions. (This clause is
+ * necessary due to a potential bad interaction between the GPL and
+ * the restrictions contained in a BSD-style copyright.)
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF
+ * WHICH ARE HEREBY DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+ * USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * DRBG Usage
+ * ==========
+ * The SP 800-90A DRBG allows the user to specify a personalization string
+ * for initialization as well as an additional information string for each
+ * random number request. The following code fragments show how a caller
+ * uses the kernel crypto API to use the full functionality of the DRBG.
+ *
+ * Usage without any additional data
+ * ---------------------------------
+ * struct crypto_rng *drng;
+ * int err;
+ * char data[DATALEN];
+ *
+ * drng = crypto_alloc_rng(drng_name, 0, 0);
+ * err = crypto_rng_get_bytes(drng, &data, DATALEN);
+ * crypto_free_rng(drng);
+ *
+ *
+ * Usage with personalization string during initialization
+ * -------------------------------------------------------
+ * struct crypto_rng *drng;
+ * int err;
+ * char data[DATALEN];
+ * struct drbg_string pers;
+ * char personalization[11] = "some-string";
+ *
+ * drbg_string_fill(&pers, personalization, strlen(personalization));
+ * drng = crypto_alloc_rng(drng_name, 0, 0);
+ * // The reset completely re-initializes the DRBG with the provided
+ * // personalization string
+ * err = crypto_rng_reset(drng, &personalization, strlen(personalization));
+ * err = crypto_rng_get_bytes(drng, &data, DATALEN);
+ * crypto_free_rng(drng);
+ *
+ *
+ * Usage with additional information string during random number request
+ * ---------------------------------------------------------------------
+ * struct crypto_rng *drng;
+ * int err;
+ * char data[DATALEN];
+ * char addtl_string[11] = "some-string";
+ * string drbg_string addtl;
+ *
+ * drbg_string_fill(&addtl, addtl_string, strlen(addtl_string));
+ * drng = crypto_alloc_rng(drng_name, 0, 0);
+ * // The following call is a wrapper to crypto_rng_get_bytes() and returns
+ * // the same error codes.
+ * err = crypto_drbg_get_bytes_addtl(drng, &data, DATALEN, &addtl);
+ * crypto_free_rng(drng);
+ *
+ *
+ * Usage with personalization and additional information strings
+ * -------------------------------------------------------------
+ * Just mix both scenarios above.
+ */
+
+#include <crypto/drbg.h>
+
+#if !defined(CONFIG_CRYPTO_DRBG_HASH) && \
+ !defined(CONFIG_CRYPTO_DRBG_HMAC) && \
+ !defined(CONFIG_CRYPTO_DRBG_CTR)
+#warning "The DRBG code is useless without compiling at least one DRBG type"
+#endif
+
+/***************************************************************
+ * Backend cipher definitions available to DRBG
+ ***************************************************************/
+
+const struct drbg_core cores[] = {
+ /* Hash DRBGs */
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+ {
+ .flags = DRBG_HASH | DRBG_STRENGTH128,
+ .statelen = 55, /* 440 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 20,
+ .cra_name = "sha1",
+ .cra_driver_name = "sha1",
+ .backend_cra_name = "sha1",
+ }, {
+ .flags = DRBG_HASH | DRBG_STRENGTH256,
+ .statelen = 55, /* 440 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 32,
+ .cra_name = "sha256",
+ .cra_driver_name = "sha256",
+ .backend_cra_name = "sha256",
+ }, {
+ .flags = DRBG_HASH | DRBG_STRENGTH256,
+ .statelen = 111, /* 888 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 48,
+ .cra_name = "sha384",
+ .cra_driver_name = "sha384",
+ .backend_cra_name = "sha384",
+ }, {
+ .flags = DRBG_HASH | DRBG_STRENGTH256,
+ .statelen = 111, /* 888 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 64,
+ .cra_name = "sha512",
+ .cra_driver_name = "sha512",
+ .backend_cra_name = "sha512",
+ },
+#endif /* CONFIG_CRYPTO_DRBG_HASH */
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+ {
+ /* HMAC DRBGs */
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 20, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 20,
+ .cra_name = "hmac(sha1)",
+ .cra_driver_name = "hmac_sha1",
+ .backend_cra_name = "hmac(sha1)",
+ }, {
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 32, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 32,
+ .cra_name = "hmac(sha256)",
+ .cra_driver_name = "hmac_sha256",
+ .backend_cra_name = "hmac(sha256)",
+ }, {
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 48, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 48,
+ .cra_name = "hmac(sha384)",
+ .cra_driver_name = "hmac_sha384",
+ .backend_cra_name = "hmac(sha384)",
+ }, {
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 64, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 64,
+ .cra_name = "hmac(sha512)",
+ .cra_driver_name = "hmac_sha512",
+ .backend_cra_name = "hmac(sha512)",
+ },
+#endif /* CONFIG_CRYPTO_DRBG_HMAC */
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+ {
+ /* block ciphers */
+ .flags = DRBG_CTR | DRBG_STRENGTH128,
+ .statelen = 32, /* 256 bits as defined in 10.2.1 */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 16,
+ .cra_name = "ctr(aes128)",
+ .cra_driver_name = "ctr_aes128",
+ .backend_cra_name = "ecb(aes)",
+ }, {
+ /* block ciphers */
+ .flags = DRBG_CTR | DRBG_STRENGTH192,
+ .statelen = 40, /* 320 bits as defined in 10.2.1 */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 16,
+ .cra_name = "ctr(aes192)",
+ .cra_driver_name = "ctr_aes192",
+ .backend_cra_name = "ecb(aes)",
+ }, {
+ /* block ciphers */
+ .flags = DRBG_CTR | DRBG_STRENGTH256,
+ .statelen = 48, /* 384 bits as defined in 10.2.1 */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 16,
+ .cra_name = "ctr(aes256)",
+ .cra_driver_name = "ctr_aes256",
+ .backend_cra_name = "ecb(aes)",
+ },
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+};
+
+/******************************************************************
+ * Generic helper functions
+ ******************************************************************/
+
+/*
+ * Return strength of DRBG according to SP800-90A section 8.4
+ *
+ * @flags DRBG flags reference
+ *
+ * Return: normalized strength in *bytes* value or 32 as default
+ * to counter programming errors
+ */
+static inline unsigned short drbg_sec_strength(drbg_flag_t flags)
+{
+ switch (flags & DRBG_STRENGTH_MASK) {
+ case DRBG_STRENGTH128:
+ return 16;
+ case DRBG_STRENGTH192:
+ return 24;
+ case DRBG_STRENGTH256:
+ return 32;
+ default:
+ return 32;
+ }
+}
+
+/*
+ * FIPS 140-2 continuous self test
+ * The test is performed on the result of one round of the output
+ * function. Thus, the function implicitly knows the size of the
+ * buffer.
+ *
+ * The FIPS test can be called in an endless loop until it returns
+ * true. Although the code looks like a potential for a deadlock, it
+ * is not the case, because returning a false cannot mathematically
+ * occur (except once when a reseed took place and the updated state
+ * would is now set up such that the generation of new value returns
+ * an identical one -- this is most unlikely and would happen only once).
+ * Thus, if this function repeatedly returns false and thus would cause
+ * a deadlock, the integrity of the entire kernel is lost.
+ *
+ * @drbg DRBG handle
+ * @buf output buffer of random data to be checked
+ *
+ * return:
+ * true on success
+ * false on error
+ */
+static bool drbg_fips_continuous_test(struct drbg_state *drbg,
+ unsigned char *buf)
+{
+#ifdef CONFIG_CRYPTO_FIPS
+ int ret = 0;
+ /* skip test if we test the overall system */
+ if (drbg->test_data)
+ return true;
+ /* only perform test in FIPS mode */
+ if (0 == fips_enabled)
+ return true;
+ if (!drbg->fips_primed) {
+ /* Priming of FIPS test */
+ memcpy(drbg->prev, buf, drbg_blocklen(drbg));
+ drbg->fips_primed = true;
+ /* return false due to priming, i.e. another round is needed */
+ return false;
+ }
+ ret = memcmp(drbg->prev, buf, drbg_blocklen(drbg));
+ memcpy(drbg->prev, buf, drbg_blocklen(drbg));
+ /* the test shall pass when the two compared values are not equal */
+ return ret != 0;
+#else
+ return true;
+#endif /* CONFIG_CRYPTO_FIPS */
+}
+
+/*
+ * Convert an integer into a byte representation of this integer.
+ * The byte representation is big-endian
+ *
+ * @buf buffer holding the converted integer
+ * @val value to be converted
+ * @buflen length of buffer
+ */
+#if (defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_CTR))
+static inline void drbg_int2byte(unsigned char *buf, uint64_t val,
+ size_t buflen)
+{
+ unsigned char *byte;
+ uint64_t i;
+
+ byte = buf + (buflen - 1);
+ for (i = 0; i < buflen; i++)
+ *(byte--) = val >> (i * 8) & 0xff;
+}
+
+/*
+ * Increment buffer
+ *
+ * @dst buffer to increment
+ * @add value to add
+ */
+static inline void drbg_add_buf(unsigned char *dst, size_t dstlen,
+ unsigned char *add, size_t addlen)
+{
+ /* implied: dstlen > addlen */
+ unsigned char *dstptr, *addptr;
+ unsigned int remainder = 0;
+ size_t len = addlen;
+
+ dstptr = dst + (dstlen-1);
+ addptr = add + (addlen-1);
+ while (len) {
+ remainder += *dstptr + *addptr;
+ *dstptr = remainder & 0xff;
+ remainder >>= 8;
+ len--; dstptr--; addptr--;
+ }
+ len = dstlen - addlen;
+ while (len && remainder > 0) {
+ remainder = *dstptr + 1;
+ *dstptr = remainder & 0xff;
+ remainder >>= 8;
+ len--; dstptr--;
+ }
+}
+#endif /* defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_CTR) */
+
+/******************************************************************
+ * CTR DRBG callback functions
+ ******************************************************************/
+
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+static int drbg_kcapi_sym(struct drbg_state *drbg, unsigned char *key,
+ unsigned char *outval, struct drbg_string *in);
+static int drbg_init_sym_kernel(struct drbg_state *drbg);
+static int drbg_fini_sym_kernel(struct drbg_state *drbg);
+
+/* BCC function for CTR DRBG as defined in 10.4.3 */
+static int drbg_ctr_bcc(struct drbg_state *drbg,
+ unsigned char *out, unsigned char *key,
+ struct drbg_string *in)
+{
+ int ret = -EFAULT;
+ struct drbg_string *curr = in;
+ size_t inpos = curr->len;
+ const unsigned char *pos = curr->buf;
+ struct drbg_string data;
+
+ drbg_string_fill(&data, out, drbg_blocklen(drbg));
+
+ /* 10.4.3 step 1 */
+ memset(out, 0, drbg_blocklen(drbg));
+
+ /* 10.4.3 step 2 / 4 */
+ while (inpos) {
+ short cnt = 0;
+ /* 10.4.3 step 4.1 */
+ for (cnt = 0; cnt < drbg_blocklen(drbg); cnt++) {
+ out[cnt] ^= *pos;
+ pos++; inpos--;
+ /* the following branch implements the linked list
+ * iteration. If we are at the end of the current data
+ * set, we have to start using the next data set if
+ * available -- the inpos value always points to the
+ * current byte and will be zero if we have processed
+ * the last byte of the last linked list member */
+ if (0 == inpos) {
+ curr = curr->next;
+ if (NULL != curr) {
+ pos = curr->buf;
+ inpos = curr->len;
+ } else {
+ inpos = 0;
+ break;
+ }
+ }
+ }
+ /* 10.4.3 step 4.2 */
+ ret = drbg_kcapi_sym(drbg, key, out, &data);
+ if (ret)
+ return ret;
+ /* 10.4.3 step 2 */
+ }
+ return 0;
+}
+
+/*
+ * scratchpad usage: drbg_ctr_update is interlinked with drbg_ctr_df
+ * (and drbg_ctr_bcc, but this function does not need any temporary buffers),
+ * the scratchpad is used as follows:
+ * drbg_ctr_update:
+ * temp
+ * start: drbg->scratchpad
+ * length: drbg_statelen(drbg) + drbg_blocklen(drbg)
+ * note: the cipher writing into this variable works
+ * blocklen-wise. Now, when the statelen is not a multiple
+ * of blocklen, the generateion loop below "spills over"
+ * by at most blocklen. Thus, we need to give sufficient
+ * memory.
+ * df_data
+ * start: drbg->scratchpad +
+ * drbg_statelen(drbg) + drbg_blocklen(drbg)
+ * length: drbg_statelen(drbg)
+ *
+ * drbg_ctr_df:
+ * pad
+ * start: df_data + drbg_statelen(drbg)
+ * length: drbg_blocklen(drbg)
+ * iv
+ * start: pad + drbg_blocklen(drbg)
+ * length: drbg_blocklen(drbg)
+ * temp
+ * start: iv + drbg_blocklen(drbg)
+ * length: (drbg_keylen(drbg) + drbg_blocklen(drbg) ==
+ * drbg_statelen(drbg))
+ */
+
+/* Derivation Function for CTR DRBG as defined in 10.4.2 */
+static int drbg_ctr_df(struct drbg_state *drbg,
+ unsigned char *df_data, size_t bytes_to_return,
+ struct drbg_string *addtl)
+{
+ int ret = -EFAULT;
+ unsigned char L_N[8];
+ /* S3 is input */
+ struct drbg_string S1, S2, S4, cipherin;
+ struct drbg_string *tempstr = addtl;
+ unsigned char *pad = df_data + drbg_statelen(drbg);
+ unsigned char *iv = pad + drbg_blocklen(drbg);
+ unsigned char *temp = iv + drbg_blocklen(drbg);
+ size_t padlen = 0;
+ unsigned int templen = 0;
+ /* 10.4.2 step 7 */
+ unsigned int i = 0;
+ /* 10.4.2 step 8 */
+ unsigned char *K = (unsigned char *)
+ "\x00\x01\x02\x03\x04\x05\x06\x07"
+ "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f"
+ "\x10\x11\x12\x13\x14\x15\x16\x17"
+ "\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f";
+ unsigned char *X;
+ size_t generated_len = 0;
+ size_t inputlen = 0;
+
+ memset(pad, 0, drbg_blocklen(drbg));
+ memset(iv, 0, drbg_blocklen(drbg));
+ memset(temp, 0, drbg_statelen(drbg));
+
+ /* 10.4.2 step 1 is implicit as we work byte-wise */
+
+ /* 10.4.2 step 2 */
+ if ((512/8) < bytes_to_return)
+ return -EINVAL;
+
+ /* 10.4.2 step 2 -- calculate the entire length of all input data */
+ for (; NULL != tempstr; tempstr = tempstr->next)
+ inputlen += tempstr->len;
+ drbg_int2byte(&L_N[0], inputlen, 4);
+
+ /* 10.4.2 step 3 */
+ drbg_int2byte(&L_N[4], bytes_to_return, 4);
+
+ /* 10.4.2 step 5: length is L_N, input_string, one byte, padding */
+ padlen = (inputlen + sizeof(L_N) + 1) % (drbg_blocklen(drbg));
+ /* wrap the padlen appropriately */
+ if (padlen)
+ padlen = drbg_blocklen(drbg) - padlen;
+ /* pad / padlen contains the 0x80 byte and the following zero bytes, so
+ * add one for byte for 0x80 */
+ padlen++;
+ pad[0] = 0x80;
+
+ /* 10.4.2 step 4 -- first fill the linked list and then order it */
+ drbg_string_fill(&S1, iv, drbg_blocklen(drbg));
+ drbg_string_fill(&S2, L_N, sizeof(L_N));
+ drbg_string_fill(&S4, pad, padlen);
+ S1.next = &S2;
+ S2.next = addtl;
+ /* splice in addtl between S2 and S4 -- we place S4 at the end of the
+ * input data chain */
+ tempstr = addtl;
+ for (; NULL != tempstr; tempstr = tempstr->next)
+ if (NULL == tempstr->next)
+ break;
+ tempstr->next = &S4;
+
+ /* 10.4.2 step 9 */
+ while (templen < (drbg_keylen(drbg) + (drbg_blocklen(drbg)))) {
+ /* 10.4.2 step 9.1 - the padding is implicit as the buffer
+ * holds zeros after allocation -- even the increment of i
+ * is irrelevant as the increment remains within length of i */
+ drbg_int2byte(iv, i, 4);
+ /* 10.4.2 step 9.2 -- BCC and concatenation with temp */
+ ret = drbg_ctr_bcc(drbg, temp + templen, K, &S1);
+ if (ret)
+ goto out;
+ /* 10.4.2 step 9.3 */
+ i++;
+ templen += drbg_blocklen(drbg);
+ }
+
+ /* 10.4.2 step 11 */
+ /* implicit key len with seedlen - blocklen according to table 3 */
+ X = temp + (drbg_keylen(drbg));
+ drbg_string_fill(&cipherin, X, drbg_blocklen(drbg));
+
+ /* 10.4.2 step 12: overwriting of outval */
+
+ /* 10.4.2 step 13 */
+ while (generated_len < bytes_to_return) {
+ short blocklen = 0;
+ /* 10.4.2 step 13.1 */
+ /* the truncation of the key length is implicit as the key
+ * is only drbg_blocklen in size -- check for the implementation
+ * of the cipher function callback */
+ ret = drbg_kcapi_sym(drbg, temp, X, &cipherin);
+ if (ret)
+ goto out;
+ blocklen = (drbg_blocklen(drbg) <
+ (bytes_to_return - generated_len)) ?
+ drbg_blocklen(drbg) :
+ (bytes_to_return - generated_len);
+ /* 10.4.2 step 13.2 and 14 */
+ memcpy(df_data + generated_len, X, blocklen);
+ generated_len += blocklen;
+ }
+
+ ret = 0;
+
+out:
+ memset(iv, 0, drbg_blocklen(drbg));
+ memset(temp, 0, drbg_statelen(drbg));
+ memset(pad, 0, drbg_blocklen(drbg));
+ return ret;
+}
+
+/* update function of CTR DRBG as defined in 10.2.1.2 */
+static int drbg_ctr_update(struct drbg_state *drbg,
+ struct drbg_string *addtl, int reseed)
+{
+ int ret = -EFAULT;
+ /* 10.2.1.2 step 1 */
+ unsigned char *temp = drbg->scratchpad;
+ unsigned char *df_data = drbg->scratchpad + drbg_statelen(drbg) +
+ drbg_blocklen(drbg);
+ unsigned char *temp_p, *df_data_p; /* pointer to iterate over buffers */
+ unsigned int len = 0;
+ struct drbg_string cipherin;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ memset(temp, 0, drbg_statelen(drbg) + drbg_blocklen(drbg));
+ memset(df_data, 0, drbg_statelen(drbg));
+
+ /* 10.2.1.3.2 step 2 and 10.2.1.4.2 step 2 */
+ if (addtl && 0 < addtl->len) {
+ ret = drbg_ctr_df(drbg, df_data, drbg_statelen(drbg),
+ addtl);
+ if (ret)
+ goto out;
+ }
+
+ drbg_string_fill(&cipherin, drbg->V, drbg_blocklen(drbg));
+ /* 10.2.1.3.2 step 2 and 3 -- are already covered as we memset(0)
+ * all memory during initialization */
+ while (len < (drbg_statelen(drbg))) {
+ /* 10.2.1.2 step 2.1 */
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ /* 10.2.1.2 step 2.2 */
+ /* using target of temp + len: 10.2.1.2 step 2.3 and 3 */
+ ret = drbg_kcapi_sym(drbg, drbg->C, temp + len, &cipherin);
+ if (ret)
+ goto out;
+ /* 10.2.1.2 step 2.3 and 3 */
+ len += drbg_blocklen(drbg);
+ }
+
+ /* 10.2.1.2 step 4 */
+ temp_p = temp;
+ df_data_p = df_data;
+ for (len = 0; len < drbg_statelen(drbg); len++) {
+ *temp_p ^= *df_data_p;
+ df_data_p++; temp_p++;
+ }
+
+ /* 10.2.1.2 step 5 */
+ memcpy(drbg->C, temp, drbg_keylen(drbg));
+ /* 10.2.1.2 step 6 */
+ memcpy(drbg->V, temp + drbg_keylen(drbg), drbg_blocklen(drbg));
+ ret = 0;
+
+out:
+ memset(temp, 0, drbg_statelen(drbg) + drbg_blocklen(drbg));
+ memset(df_data, 0, drbg_statelen(drbg));
+ return ret;
+}
+
+/*
+ * scratchpad use: drbg_ctr_update is called independently from
+ * drbg_ctr_extract_bytes. Therefore, the scratchpad is reused
+ */
+/* Generate function of CTR DRBG as defined in 10.2.1.5.2 */
+static int drbg_ctr_generate(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ int len = 0;
+ int ret = 0;
+ struct drbg_string data;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+
+ /* 10.2.1.5.2 step 2 */
+ if (addtl && 0 < addtl->len) {
+ addtl->next = NULL;
+ ret = drbg_ctr_update(drbg, addtl, 1);
+ if (ret)
+ return 0;
+ }
+
+ /* 10.2.1.5.2 step 4.1 */
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ drbg_string_fill(&data, drbg->V, drbg_blocklen(drbg));
+ while (len < buflen) {
+ int outlen = 0;
+ /* 10.2.1.5.2 step 4.2 */
+ ret = drbg_kcapi_sym(drbg, drbg->C, drbg->scratchpad, &data);
+ if (ret) {
+ len = ret;
+ goto out;
+ }
+ outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
+ drbg_blocklen(drbg) : (buflen - len);
+ if (!drbg_fips_continuous_test(drbg, drbg->scratchpad)) {
+ /* 10.2.1.5.2 step 6 */
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ continue;
+ }
+ /* 10.2.1.5.2 step 4.3 */
+ memcpy(buf + len, drbg->scratchpad, outlen);
+ len += outlen;
+ /* 10.2.1.5.2 step 6 */
+ if (len < buflen)
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ }
+
+ /* 10.2.1.5.2 step 6 */
+ /*TODO the DF function is called again since according to step
+ * 2, the "additional_input" after step 2 is the output of the DF
+ * function -- when we save the DF output as a replacement
+ * for the addtl_input data, we do not need to call the DF again here */
+ if (addtl)
+ addtl->next = NULL;
+ ret = drbg_ctr_update(drbg, addtl, 1);
+ if (ret)
+ len = ret;
+
+out:
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ return len;
+}
+
+static struct drbg_state_ops drbg_ctr_ops = {
+ .update = drbg_ctr_update,
+ .generate = drbg_ctr_generate,
+ .crypto_init = drbg_init_sym_kernel,
+ .crypto_fini = drbg_fini_sym_kernel,
+};
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+
+/******************************************************************
+ * HMAC DRBG callback functions
+ ******************************************************************/
+
+#if defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_HMAC)
+static int drbg_kcapi_hash(struct drbg_state *drbg, unsigned char *key,
+ unsigned char *outval, struct drbg_string *in);
+static int drbg_init_hash_kernel(struct drbg_state *drbg);
+static int drbg_fini_hash_kernel(struct drbg_state *drbg);
+#endif /* (CONFIG_CRYPTO_DRBG_HASH || CONFIG_CRYPTO_DRBG_HMAC) */
+
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+/* update function of HMAC DRBG as defined in 10.1.2.2 */
+static int drbg_hmac_update(struct drbg_state *drbg, struct drbg_string *seed,
+ int reseed)
+{
+ int ret = -EFAULT;
+ int i = 0;
+ struct drbg_string seed1, seed2, cipherin;
+
+ if (!reseed) {
+ /* 10.1.2.3 step 2 already implicitly covered with
+ * the initial memset(0) of drbg->C */
+ memset(drbg->C, 0, drbg_statelen(drbg));
+ memset(drbg->V, 1, drbg_statelen(drbg));
+ }
+
+ /* build linked list which implements the concatenation and fill
+ * first part*/
+ drbg_string_fill(&seed1, drbg->V, drbg_statelen(drbg));
+ /* buffer will be filled in for loop below with one byte */
+ drbg_string_fill(&seed2, NULL, 1);
+ seed1.next = &seed2;
+ /* seed may be NULL */
+ seed2.next = seed;
+
+ drbg_string_fill(&cipherin, drbg->V, drbg_statelen(drbg));
+ /* we execute two rounds of V/K massaging */
+ for (i = 2; 0 < i; i--) {
+ /* first round uses 0x0, second 0x1 */
+ unsigned char prefix = DRBG_PREFIX0;
+ if (1 == i)
+ prefix = DRBG_PREFIX1;
+ /* 10.1.2.2 step 1 and 4 -- concatenation and HMAC for key */
+ seed2.buf = &prefix;
+ ret = drbg_kcapi_hash(drbg, drbg->C, drbg->C, &seed1);
+ if (ret)
+ return ret;
+
+ /* 10.1.2.2 step 2 and 5 -- HMAC for V */
+ ret = drbg_kcapi_hash(drbg, drbg->C, drbg->V, &cipherin);
+ if (ret)
+ return ret;
+
+ /* 10.1.2.2 step 3 */
+ if (!seed || 0 == seed->len)
+ return ret;
+ }
+
+ return 0;
+}
+
+/* generate function of HMAC DRBG as defined in 10.1.2.5 */
+static int drbg_hmac_generate(struct drbg_state *drbg,
+ unsigned char *buf,
+ unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ int len = 0;
+ int ret = 0;
+ struct drbg_string data;
+
+ /* 10.1.2.5 step 2 */
+ if (addtl && 0 < addtl->len) {
+ addtl->next = NULL;
+ ret = drbg_hmac_update(drbg, addtl, 1);
+ if (ret)
+ return ret;
+ }
+
+ drbg_string_fill(&data, drbg->V, drbg_statelen(drbg));
+ while (len < buflen) {
+ unsigned int outlen = 0;
+ /* 10.1.2.5 step 4.1 */
+ ret = drbg_kcapi_hash(drbg, drbg->C, drbg->V, &data);
+ if (ret)
+ return ret;
+ outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
+ drbg_blocklen(drbg) : (buflen - len);
+ if (!drbg_fips_continuous_test(drbg, drbg->V))
+ continue;
+
+ /* 10.1.2.5 step 4.2 */
+ memcpy(buf + len, drbg->V, outlen);
+ len += outlen;
+ }
+
+ /* 10.1.2.5 step 6 */
+ if (addtl)
+ addtl->next = NULL;
+ ret = drbg_hmac_update(drbg, addtl, 1);
+ if (ret)
+ return ret;
+
+ return len;
+}
+
+static struct drbg_state_ops drbg_hmac_ops = {
+ .update = drbg_hmac_update,
+ .generate = drbg_hmac_generate,
+ .crypto_init = drbg_init_hash_kernel,
+ .crypto_fini = drbg_fini_hash_kernel,
+
+};
+#endif /* CONFIG_CRYPTO_DRBG_HMAC */
+
+/******************************************************************
+ * Hash DRBG callback functions
+ ******************************************************************/
+
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+/*
+ * scratchpad usage: as drbg_hash_update and drbg_hash_df are used
+ * interlinked, the scratchpad is used as follows:
+ * drbg_hash_update
+ * start: drbg->scratchpad
+ * length: drbg_statelen(drbg)
+ * drbg_hash_df:
+ * start: drbg->scratchpad + drbg_statelen(drbg)
+ * length: drbg_blocklen(drbg)
+ */
+/* Derivation Function for Hash DRBG as defined in 10.4.1 */
+static int drbg_hash_df(struct drbg_state *drbg,
+ unsigned char *outval, size_t outlen,
+ struct drbg_string *entropy)
+{
+ int ret = 0;
+ size_t len = 0;
+ unsigned char input[5];
+ unsigned char *tmp = drbg->scratchpad + drbg_statelen(drbg);
+ struct drbg_string data1;
+
+ memset(tmp, 0, drbg_blocklen(drbg));
+
+ /* 10.4.1 step 3 */
+ input[0] = 1;
+ drbg_int2byte(&input[1], (outlen * 8), 4);
+
+ /* 10.4.1 step 4.1 -- concatenation of data for input into hash */
+ drbg_string_fill(&data1, input, 5);
+ data1.next = entropy;
+
+ /* 10.4.1 step 4 */
+ while (len < outlen) {
+ short blocklen = 0;
+ /* 10.4.1 step 4.1 */
+ ret = drbg_kcapi_hash(drbg, NULL, tmp, &data1);
+ if (ret)
+ goto out;
+ /* 10.4.1 step 4.2 */
+ input[0]++;
+ blocklen = (drbg_blocklen(drbg) < (outlen - len)) ?
+ drbg_blocklen(drbg) : (outlen - len);
+ memcpy(outval + len, tmp, blocklen);
+ len += blocklen;
+ }
+
+out:
+ memset(tmp, 0, drbg_blocklen(drbg));
+ return ret;
+}
+
+/* update function for Hash DRBG as defined in 10.1.1.2 / 10.1.1.3 */
+static int drbg_hash_update(struct drbg_state *drbg, struct drbg_string *seed,
+ int reseed)
+{
+ int ret = 0;
+ struct drbg_string data1, data2;
+ unsigned char *V = drbg->scratchpad;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ memset(drbg->scratchpad, 0, drbg_statelen(drbg));
+ if (!seed)
+ return -EINVAL;
+
+ if (reseed) {
+ /* 10.1.1.3 step 1: string length is concatenation of
+ * 1 byte, V and seed (which is concatenated entropy/addtl
+ * input)
+ */
+ memcpy(V, drbg->V, drbg_statelen(drbg));
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, V, drbg_statelen(drbg));
+ data1.next = &data2;
+ data2.next = seed;
+ } else {
+ drbg_string_fill(&data1, seed->buf, seed->len);
+ data1.next = seed->next;
+ }
+
+ /* 10.1.1.2 / 10.1.1.3 step 2 and 3 */
+ ret = drbg_hash_df(drbg, drbg->V, drbg_statelen(drbg), &data1);
+ if (ret)
+ goto out;
+
+ /* 10.1.1.2 / 10.1.1.3 step 4 -- concatenation */
+ prefix = DRBG_PREFIX0;
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, drbg->V, drbg_statelen(drbg));
+ data1.next = &data2;
+ /* 10.1.1.2 / 10.1.1.3 step 4 -- df operation */
+ ret = drbg_hash_df(drbg, drbg->C, drbg_statelen(drbg), &data1);
+
+out:
+ memset(drbg->scratchpad, 0, drbg_statelen(drbg));
+ return ret;
+}
+
+/* processing of additional information string for Hash DRBG */
+static int drbg_hash_process_addtl(struct drbg_state *drbg,
+ struct drbg_string *addtl)
+{
+ int ret = 0;
+ struct drbg_string data1, data2;
+ struct drbg_string *data3;
+ unsigned char prefix = DRBG_PREFIX2;
+
+ /* this is value w as per documentation */
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+
+ /* 10.1.1.4 step 2 */
+ if (!addtl || 0 == addtl->len)
+ return 0;
+
+ /* 10.1.1.4 step 2a -- concatenation */
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, drbg->V, drbg_statelen(drbg));
+ data3 = addtl;
+ data1.next = &data2;
+ data2.next = data3;
+ data3->next = NULL;
+ /* 10.1.1.4 step 2a -- cipher invocation */
+ ret = drbg_kcapi_hash(drbg, NULL, drbg->scratchpad, &data1);
+ if (ret)
+ goto out;
+
+ /* 10.1.1.4 step 2b */
+ drbg_add_buf(drbg->V, drbg_statelen(drbg),
+ drbg->scratchpad, drbg_blocklen(drbg));
+
+out:
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ return ret;
+}
+
+/*
+ * Hashgen defined in 10.1.1.4
+ */
+static int drbg_hash_hashgen(struct drbg_state *drbg,
+ unsigned char *buf,
+ unsigned int buflen)
+{
+ int len = 0;
+ int ret = 0;
+ unsigned char *src = drbg->scratchpad;
+ unsigned char *dst = drbg->scratchpad + drbg_statelen(drbg);
+ struct drbg_string data;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ /* use the scratchpad as a lookaside buffer */
+ memset(src, 0, drbg_statelen(drbg));
+ memset(dst, 0, drbg_blocklen(drbg));
+
+ /* 10.1.1.4 step hashgen 2 */
+ memcpy(src, drbg->V, drbg_statelen(drbg));
+
+ drbg_string_fill(&data, src, drbg_statelen(drbg));
+ while (len < buflen) {
+ unsigned int outlen = 0;
+ /* 10.1.1.4 step hashgen 4.1 */
+ ret = drbg_kcapi_hash(drbg, NULL, dst, &data);
+ if (ret) {
+ len = ret;
+ goto out;
+ }
+ outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
+ drbg_blocklen(drbg) : (buflen - len);
+ if (!drbg_fips_continuous_test(drbg, dst)) {
+ drbg_add_buf(src, drbg_statelen(drbg), &prefix, 1);
+ continue;
+ }
+ /* 10.1.1.4 step hashgen 4.2 */
+ memcpy(buf + len, dst, outlen);
+ len += outlen;
+ /* 10.1.1.4 hashgen step 4.3 */
+ if (len < buflen)
+ drbg_add_buf(src, drbg_statelen(drbg), &prefix, 1);
+ }
+
+out:
+ memset(drbg->scratchpad, 0,
+ (drbg_statelen(drbg) + drbg_blocklen(drbg)));
+ return len;
+}
+
+/* generate function for Hash DRBG as defined in 10.1.1.4 */
+static int drbg_hash_generate(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ int len = 0;
+ int ret = 0;
+ unsigned char req[8];
+ unsigned char prefix = DRBG_PREFIX3;
+ struct drbg_string data1, data2;
+
+ /*
+ * scratchpad usage: drbg_hash_process_addtl uses the scratchpad, but
+ * fully completes before returning. Thus, we can reuse the scratchpad
+ */
+ /* 10.1.1.4 step 2 */
+ ret = drbg_hash_process_addtl(drbg, addtl);
+ if (ret)
+ return ret;
+ /* 10.1.1.4 step 3 -- invocation of the Hashgen function defined in
+ * 10.1.1.4 */
+ len = drbg_hash_hashgen(drbg, buf, buflen);
+
+ /* this is the value H as documented in 10.1.1.4 */
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ /* 10.1.1.4 step 4 */
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, drbg->V, drbg_statelen(drbg));
+ data1.next = &data2;
+ ret = drbg_kcapi_hash(drbg, NULL, drbg->scratchpad, &data1);
+ if (ret) {
+ len = ret;
+ goto out;
+ }
+
+ /* 10.1.1.4 step 5 */
+ drbg_add_buf(drbg->V, drbg_statelen(drbg),
+ drbg->scratchpad, drbg_blocklen(drbg));
+ drbg_add_buf(drbg->V, drbg_statelen(drbg),
+ drbg->C, drbg_statelen(drbg));
+ drbg_int2byte(req, drbg->reseed_ctr, sizeof(req));
+ drbg_add_buf(drbg->V, drbg_statelen(drbg), req, 8);
+
+out:
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ return len;
+}
+
+/*
+ * scratchpad usage: as update and generate are used isolated, both
+ * can use the scratchpad
+ */
+static struct drbg_state_ops drbg_hash_ops = {
+ .update = drbg_hash_update,
+ .generate = drbg_hash_generate,
+ .crypto_init = drbg_init_hash_kernel,
+ .crypto_fini = drbg_fini_hash_kernel,
+};
+#endif /* CONFIG_CRYPTO_DRBG_HASH */
+
+/******************************************************************
+ * Functions common for DRBG implementations
+ ******************************************************************/
+
+/*
+ * Seeding or reseeding of the DRBG
+ *
+ * @drbg: DRBG state struct
+ * @pers: personalization / additional information buffer
+ * @reseed: 0 for initial seed process, 1 for reseeding
+ *
+ * return:
+ * 0 on success
+ * error value otherwise
+ */
+static int drbg_seed(struct drbg_state *drbg, struct drbg_string *pers,
+ bool reseed)
+{
+ int ret = 0;
+ unsigned char *entropy = NULL;
+ size_t entropylen = 0;
+ struct drbg_string data1;
+ struct drbg_string *data2;
+
+ /* 9.1 / 9.2 / 9.3.1 step 3 */
+ if (pers && pers->len > (drbg_max_addtl(drbg))) {
+ pr_devel("DRBG: personalization string too long %lu\n",
+ pers->len);
+ return -EINVAL;
+ }
+
+ if (drbg->test_data && drbg->test_data->testentropy) {
+ drbg_string_fill(&data1, drbg->test_data->testentropy->buf,
+ drbg->test_data->testentropy->len);
+ pr_devel("DRBG: using test entropy\n");
+ } else {
+ /* Gather entropy equal to the security strength of the DRBG.
+ * With a derivation function, a nonce is required in addition
+ * to the entropy. A nonce must be at least 1/2 of the security
+ * strength of the DRBG in size. Thus, entropy * nonce is 3/2
+ * of the strength. The consideration of a nonce is only
+ * applicable during initial seeding. */
+ entropylen = drbg_sec_strength(drbg->core->flags);
+ if (!entropylen)
+ return -EFAULT;
+ if (!reseed)
+ /* make sure we round up strength/2 in
+ * case it is not divisible by 2 */
+ entropylen = ((entropylen + 1) / 2) * 3;
+ pr_devel("DRBG: (re)seeding with %zu bytes of entropy\n",
+ entropylen);
+ entropy = kzalloc(entropylen, GFP_KERNEL);
+ if (!entropy)
+ return -ENOMEM;
+ get_random_bytes(entropy, entropylen);
+ drbg_string_fill(&data1, entropy, entropylen);
+ }
+
+ /* concatenation of entropy with personalization str / addtl input) */
+ if (pers && 0 < pers->len) {
+ data2 = pers;
+ data2->next = NULL;
+ data1.next = data2;
+ pr_devel("DRBG: using personalization string\n");
+ }
+
+ ret = drbg->d_ops->update(drbg, &data1, reseed);
+ if (ret)
+ goto out;
+
+ drbg->seeded = true;
+ /* 10.1.1.2 / 10.1.1.3 step 5 */
+ drbg->reseed_ctr = 1;
+
+out:
+ if (entropy)
+ kzfree(entropy);
+ return ret;
+}
+
+/*
+ * Free all substructures in a DRBG state without the DRBG state structure
+ */
+static inline void drbg_dealloc_state(struct drbg_state *drbg)
+{
+ if (!drbg)
+ return;
+ if (drbg->V)
+ kzfree(drbg->V);
+ drbg->V = NULL;
+ if (drbg->C)
+ kzfree(drbg->C);
+ drbg->C = NULL;
+ if (drbg->scratchpad)
+ kzfree(drbg->scratchpad);
+ drbg->scratchpad = NULL;
+ drbg->reseed_ctr = 0;
+#ifdef CONFIG_CRYPTO_FIPS
+ if (drbg->prev)
+ kzfree(drbg->prev);
+ drbg->prev = NULL;
+ drbg->fips_primed = false;
+#endif
+}
+
+/*
+ * Allocate all sub-structures for a DRBG state
+ * The DRBG state structure must already be allocated
+ */
+static inline int drbg_alloc_state(struct drbg_state *drbg)
+{
+ int ret = -ENOMEM;
+ unsigned int sb_size = 0;
+
+ if (!drbg)
+ return -EINVAL;
+
+ drbg->V = kzalloc(drbg_statelen(drbg), GFP_KERNEL);
+ if (!drbg->V)
+ goto err;
+ drbg->C = kzalloc(drbg_statelen(drbg), GFP_KERNEL);
+ if (!drbg->C)
+ goto err;
+#ifdef CONFIG_CRYPTO_FIPS
+ drbg->prev = kzalloc(drbg_blocklen(drbg), GFP_KERNEL);
+ if (!drbg->prev)
+ goto err;
+ drbg->fips_primed = false;
+#endif
+ /* scratchpad is only generated for CTR and Hash */
+ if (drbg->core->flags & DRBG_HMAC)
+ sb_size = 0;
+ else if (drbg->core->flags & DRBG_CTR)
+ sb_size = drbg_statelen(drbg) + drbg_blocklen(drbg) + /* temp */
+ drbg_statelen(drbg) + /* df_data */
+ drbg_blocklen(drbg) + /* pad */
+ drbg_blocklen(drbg) + /* iv */
+ drbg_statelen(drbg); /* temp */
+ else
+ sb_size = drbg_statelen(drbg) + drbg_blocklen(drbg);
+
+ if (0 < sb_size) {
+ drbg->scratchpad = kzalloc(sb_size, GFP_KERNEL);
+ if (!drbg->scratchpad)
+ goto err;
+ }
+ spin_lock_init(&drbg->drbg_lock);
+ return 0;
+
+err:
+ drbg_dealloc_state(drbg);
+ return ret;
+}
+
+/*
+ * Strategy to avoid holding long term locks: generate a shadow copy of DRBG
+ * and perform all operations on this shadow copy. After finishing, restore
+ * the updated state of the shadow copy into original drbg state. This way,
+ * only the read and write operations of the original drbg state must be
+ * locked
+ */
+
+/*
+ * Copy the DRBG state
+ */
+static inline void drbg_copy_drbg(struct drbg_state *src,
+ struct drbg_state *dst)
+{
+ if (!src || !dst)
+ return;
+ memcpy(dst->V, src->V, drbg_statelen(src));
+ memcpy(dst->C, src->C, drbg_statelen(src));
+ dst->reseed_ctr = src->reseed_ctr;
+ /* no copy of scratchpad */
+ /* priv_data is initialized with call to crypto_init */
+ /* d_ops and core are set outside, as these parameters are const */
+ dst->seeded = src->seeded;
+ dst->pr = src->pr;
+#ifdef CONFIG_CRYPTO_FIPS
+ dst->fips_primed = src->fips_primed;
+ memcpy(dst->prev, src->prev, drbg_blocklen(src));
+#endif
+ /* test_data is set outside to prevent it being copied back */
+}
+/*
+ * Generate shadow copy of the DRBG state
+ */
+static int drbg_make_shadow(struct drbg_state *drbg, struct drbg_state **shadow)
+{
+ int ret = -ENOMEM;
+ struct drbg_state *tmp = NULL;
+
+ /* some sanity checks */
+ if (!drbg || !drbg->core || !drbg->V || !drbg->C) {
+ pr_devel("DRBG: attempt to generate shadow copy for "
+ "uninitialized DRBG state rejected\n");
+ return -EINVAL;
+ }
+ /* HMAC does not have a scratchpad */
+ if (!(drbg->core->flags & DRBG_HMAC) && NULL == drbg->scratchpad)
+ return -EINVAL;
+
+ tmp = kzalloc(sizeof(struct drbg_state), GFP_KERNEL);
+ if (!tmp)
+ return -ENOMEM;
+
+ /* read-only data as they are defined as const, no lock needed */
+ tmp->core = drbg->core;
+ tmp->d_ops = drbg->d_ops;
+
+ ret = drbg_alloc_state(tmp);
+ if (ret)
+ goto err;
+
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg_copy_drbg(drbg, tmp);
+ /* only make a link to the test buffer, as we only read that data */
+ tmp->test_data = drbg->test_data;
+ spin_unlock_bh(&drbg->drbg_lock);
+ *shadow = tmp;
+ return 0;
+
+err:
+ if (tmp)
+ kzfree(tmp);
+ return ret;
+}
+
+/*
+ * Restore shadow state into original DRBG state
+ */
+static void drbg_restore_shadow(struct drbg_state *drbg,
+ struct drbg_state **shadow)
+{
+ struct drbg_state *tmp = *shadow;
+
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg_copy_drbg(tmp, drbg);
+ spin_unlock_bh(&drbg->drbg_lock);
+ drbg_dealloc_state(tmp);
+ kzfree(tmp);
+ *shadow = NULL;
+}
+
+/*************************************************************************
+ * DRBG interface functions
+ *************************************************************************/
+
+/*
+ * DRBG generate function as required by SP800-90A - this function
+ * generates random numbers
+ *
+ * @drbg DRBG state handle
+ * @buf Buffer where to store the random numbers -- the buffer must already
+ * be pre-allocated by caller
+ * @buflen Length of output buffer - this value defines the number of random
+ * bytes pulled from DRBG
+ * @addtl Additional input that is mixed into state, may be NULL -- note
+ * the entropy is pulled by the DRBG internally unconditionally
+ * as defined in SP800-90A. The additional input is mixed into
+ * the state in addition to the pulled entropy.
+ *
+ * return: generated number of bytes
+ */
+static int drbg_generate(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ int len = 0;
+ struct drbg_state *shadow = NULL;
+
+ if (0 == buflen || !buf) {
+ pr_devel("DRBG: no output buffer provided\n");
+ return -EINVAL;
+ }
+ if (addtl && NULL == addtl->buf && 0 < addtl->len) {
+ pr_devel("DRBG: wrong format of additional information\n");
+ return -EINVAL;
+ }
+
+ len = drbg_make_shadow(drbg, &shadow);
+ if (len) {
+ pr_devel("DRBG: shadow copy cannot be generated\n");
+ return len;
+ }
+ /* 9.3.1 step 2 */
+ len = -EINVAL;
+ if (buflen > (drbg_max_request_bytes(shadow))) {
+ pr_devel("DRBG: requested random numbers too large %u\n",
+ buflen);
+ goto err;
+ }
+ /* 9.3.1 step 3 is implicit with the chosen DRBG */
+ /* 9.3.1 step 4 */
+ if (addtl && addtl->len > (drbg_max_addtl(shadow))) {
+ pr_devel("DRBG: additional information string too long %zu\n",
+ addtl->len);
+ goto err;
+ }
+ /* 9.3.1 step 5 is implicit with the chosen DRBG */
+ /* 9.3.1 step 6 and 9 supplemented by 9.3.2 step c -- the spec is a
+ * bit convoluted here, we make it simpler */
+ if ((drbg_max_requests(shadow)) < shadow->reseed_ctr)
+ shadow->seeded = false;
+
+ /* allocate cipher handle */
+ if (shadow->d_ops->crypto_init) {
+ len = shadow->d_ops->crypto_init(shadow);
+ if (len)
+ goto err;
+ }
+
+ if (shadow->pr || !shadow->seeded) {
+ pr_devel("DRBG: reseeding before generation (prediction "
+ "resistance: %s, state %s)\n",
+ drbg->pr ? "true" : "false",
+ drbg->seeded ? "seeded" : "unseeded");
+ /* 9.3.1 steps 7.1 through 7.3 */
+ len = drbg_seed(shadow, addtl, true);
+ if (len)
+ goto err;
+ /* 9.3.1 step 7.4 */
+ addtl = NULL;
+ }
+ /* 9.3.1 step 8 and 10 */
+ len = shadow->d_ops->generate(shadow, buf, buflen, addtl);
+
+ /* 10.1.1.4 step 6, 10.1.2.5 step 7, 10.2.1.5.2 step 7 */
+ shadow->reseed_ctr++;
+ if (0 >= len)
+ goto err;
+
+ /* 11.3.3 -- re-perform self tests after some generated random
+ * numbers, the chosen value after which self test is performed
+ * is arbitrary, but it should be reasonable */
+ /* Here we do not perform the self tests because of the following
+ * reasons: it is mathematically impossible that the initial self tests
+ * were successfully and the following are not. If the initial would
+ * pass and the following would not, the kernel integrity is violated.
+ * In this case, the entire kernel operation is questionable and it
+ * is unlikely that the integrity violation only affects to the
+ * correct operation of the DRBG.
+ */
+#if 0
+ if (shadow->reseed_ctr && !(shadow->reseed_ctr % 4096)) {
+ int err = 0;
+ pr_devel("DRBG: start to perform self test\n");
+ if (drbg->core->flags & DRBG_HMAC)
+ err = alg_test("drbg(pr(hmac(sha256)))",
+ "drbg(pr(hmac(sha256)))", 0, 0);
+ else if (drbg->core->flags & DRBG_CTR)
+ err = alg_test("drbg(pr(ctr(aes128)))",
+ "drbg(pr(ctr(aes128)))", 0, 0);
+ else
+ err = alg_test("drbg(pr(sha256))",
+ "drbg(pr(sha256))", 0, 0);
+ if (err) {
+ pr_err("DRBG: periodical self test failed\n");
+ /* uninstantiate implies that from now on, only errors
+ * are returned when reusing this DRBG cipher handle */
+ drbg_uninstantiate(drbg);
+ drbg_dealloc_state(shadow);
+ kzfree(shadow);
+ return 0;
+ } else {
+ pr_devel("DRBG: self test successful\n");
+ }
+ }
+#endif
+
+err:
+ if (shadow->d_ops->crypto_fini)
+ shadow->d_ops->crypto_fini(shadow);
+ drbg_restore_shadow(drbg, &shadow);
+ return len;
+}
+
+/*
+ * Wrapper around drbg_generate which can pull arbitrary long strings
+ * from the DRBG without hitting the maximum request limitation.
+ *
+ * Parameters: see drbg_generate
+ * Return codes: see drbg_generate -- if one drbg_generate request fails,
+ * the entire drbg_generate_long request fails
+ */
+static int drbg_generate_long(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ int len = 0;
+ unsigned int slice = 0;
+ do {
+ int tmplen = 0;
+ unsigned int chunk = 0;
+ slice = ((buflen - len) / drbg_max_request_bytes(drbg));
+ chunk = slice ? drbg_max_request_bytes(drbg) : (buflen - len);
+ tmplen = drbg_generate(drbg, buf + len, chunk, addtl);
+ if (0 >= tmplen)
+ return tmplen;
+ len += tmplen;
+ } while (slice > 0);
+ return len;
+}
+
+/*
+ * DRBG instantiation function as required by SP800-90A - this function
+ * sets up the DRBG handle, performs the initial seeding and all sanity
+ * checks required by SP800-90A
+ *
+ * @drbg memory of state -- if NULL, new memory is allocated
+ * @pers Personalization string that is mixed into state, may be NULL -- note
+ * the entropy is pulled by the DRBG internally unconditionally
+ * as defined in SP800-90A. The additional input is mixed into
+ * the state in addition to the pulled entropy.
+ * @coreref reference to core
+ * @pr prediction resistance enabled
+ *
+ * return
+ * 0 on success
+ * error value otherwise
+ */
+static int drbg_instantiate(struct drbg_state *drbg, struct drbg_string *pers,
+ int coreref, bool pr)
+{
+ int ret = -ENOMEM;
+
+ pr_devel("DRBG: Initializing DRBG core %d with prediction resistance "
+ "%s\n", coreref, pr ? "enabled" : "disabled");
+ drbg->core = &cores[coreref];
+ drbg->pr = pr;
+ drbg->seeded = false;
+ switch (drbg->core->flags & DRBG_TYPE_MASK) {
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+ case DRBG_HMAC:
+ drbg->d_ops = &drbg_hmac_ops;
+ break;
+#endif /* CONFIG_CRYPTO_DRBG_HMAC */
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+ case DRBG_HASH:
+ drbg->d_ops = &drbg_hash_ops;
+ break;
+#endif /* CONFIG_CRYPTO_DRBG_HASH */
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+ case DRBG_CTR:
+ drbg->d_ops = &drbg_ctr_ops;
+ break;
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ /* 9.1 step 1 is implicit with the selected DRBG type -- see
+ * drbg_sec_strength() */
+
+ /* 9.1 step 2 is implicit as caller can select prediction resistance
+ * and the flag is copied into drbg->flags --
+ * all DRBG types support prediction resistance */
+
+ /* 9.1 step 4 is implicit in drbg_sec_strength */
+
+ /* no allocation of drbg as this is done by the kernel crypto API */
+ ret = drbg_alloc_state(drbg);
+ if (ret)
+ return ret;
+
+ ret = -EFAULT;
+ /* allocate cipher handle */
+ if (drbg->d_ops->crypto_init && drbg->d_ops->crypto_init(drbg))
+ goto err;
+ /* 9.1 step 6 through 11 */
+ ret = drbg_seed(drbg, pers, false);
+ /* deallocate cipher handle */
+ if (drbg->d_ops->crypto_fini)
+ drbg->d_ops->crypto_fini(drbg);
+ if (ret)
+ goto err;
+
+ return 0;
+
+err:
+ drbg_dealloc_state(drbg);
+ return ret;
+}
+
+/*
+ * DRBG uninstantiate function as required by SP800-90A - this function
+ * frees all buffers and the DRBG handle
+ *
+ * @drbg DRBG state handle
+ *
+ * return
+ * 0 on success
+ */
+static int drbg_uninstantiate(struct drbg_state *drbg)
+{
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg_dealloc_state(drbg);
+ /* no scrubbing of test_data -- this shall survive an uninstantiate */
+ spin_unlock_bh(&drbg->drbg_lock);
+ /* no freeing of drbg as this is done by the kernel crypto API */
+ return 0;
+}
+
+/*
+ * Helper function for setting the test data in the DRBG
+ *
+ * @drbg DRBG state handle
+ * @test_data test data to sets
+ */
+static inline void drbg_set_testdata(struct drbg_state *drbg,
+ struct drbg_test_data *test_data)
+{
+ if (!test_data || !test_data->testentropy)
+ return;
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg->test_data = test_data;
+ spin_unlock_bh(&drbg->drbg_lock);
+}
+
+/***************************************************************
+ * Kernel crypto APi cipher invocations requested by DRBG
+ ***************************************************************/
+
+#if defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_HMAC)
+struct sdesc {
+ struct shash_desc shash;
+ char ctx[];
+};
+
+static int drbg_init_hash_kernel(struct drbg_state *drbg)
+{
+ struct sdesc *sdesc;
+ struct crypto_shash *tfm;
+
+ tfm = crypto_alloc_shash(drbg->core->backend_cra_name, 0, 0);
+ if (IS_ERR(tfm)) {
+ pr_info("DRBG: could not allocate digest TFM handle\n");
+ return PTR_ERR(tfm);
+ }
+ BUG_ON(drbg_blocklen(drbg) != crypto_shash_digestsize(tfm));
+ sdesc = kzalloc(sizeof(struct shash_desc) + crypto_shash_descsize(tfm),
+ GFP_KERNEL);
+ if (!sdesc) {
+ crypto_free_shash(tfm);
+ return -ENOMEM;
+ }
+
+ sdesc->shash.tfm = tfm;
+ sdesc->shash.flags = 0;
+ drbg->priv_data = sdesc;
+ return 0;
+}
+
+static int drbg_fini_hash_kernel(struct drbg_state *drbg)
+{
+ struct sdesc *sdesc = (struct sdesc *)drbg->priv_data;
+ if (sdesc) {
+ crypto_free_shash(sdesc->shash.tfm);
+ kzfree(sdesc);
+ }
+ drbg->priv_data = NULL;
+ return 0;
+}
+
+static int drbg_kcapi_hash(struct drbg_state *drbg, unsigned char *key,
+ unsigned char *outval, struct drbg_string *in)
+{
+ struct sdesc *sdesc = (struct sdesc *)drbg->priv_data;
+
+ if (key)
+ crypto_shash_setkey(sdesc->shash.tfm, key, drbg_statelen(drbg));
+ crypto_shash_init(&sdesc->shash);
+ for (; NULL != in; in = in->next)
+ crypto_shash_update(&sdesc->shash, in->buf, in->len);
+ return crypto_shash_final(&sdesc->shash, outval);
+}
+#endif /* (CONFIG_CRYPTO_DRBG_HASH || CONFIG_CRYPTO_DRBG_HMAC) */
+
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+static int drbg_init_sym_kernel(struct drbg_state *drbg)
+{
+ int ret = 0;
+ struct crypto_blkcipher *tfm;
+
+ tfm = crypto_alloc_blkcipher(drbg->core->backend_cra_name, 0, 0);
+ if (IS_ERR(tfm)) {
+ pr_info("DRBG: could not allocate cipher TFM handle\n");
+ return PTR_ERR(tfm);
+ }
+ BUG_ON(drbg_blocklen(drbg) != crypto_blkcipher_blocksize(tfm));
+ drbg->priv_data = tfm;
+ return ret;
+}
+
+static int drbg_fini_sym_kernel(struct drbg_state *drbg)
+{
+ struct crypto_blkcipher *tfm =
+ (struct crypto_blkcipher *)drbg->priv_data;
+ if (tfm)
+ crypto_free_blkcipher(tfm);
+ drbg->priv_data = NULL;
+ return 0;
+}
+
+static int drbg_kcapi_sym(struct drbg_state *drbg, unsigned char *key,
+ unsigned char *outval, struct drbg_string *in)
+{
+ int ret = 0;
+ struct scatterlist sg_in, sg_out;
+ struct blkcipher_desc desc;
+ struct crypto_blkcipher *tfm =
+ (struct crypto_blkcipher *)drbg->priv_data;
+
+ desc.tfm = tfm;
+ desc.flags = 0;
+ crypto_blkcipher_setkey(tfm, key, (drbg_keylen(drbg)));
+ /* in is only component */
+ sg_init_one(&sg_in, in->buf, in->len);
+ sg_init_one(&sg_out, outval, drbg_blocklen(drbg));
+ ret = crypto_blkcipher_encrypt(&desc, &sg_out, &sg_in, in->len);
+
+ return ret;
+}
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+
+/***************************************************************
+ * Kernel crypto API interface to register DRBG
+ ***************************************************************/
+
+/*
+ * Look up the DRBG flags by given kernel crypto API cra_name
+ * The code uses the cores definition to do this
+ *
+ * @cra_name kernel crypto API cra_name
+ * @coreref reference to integer which is filled with the pointer to
+ * the applicable core
+ * @pr reference for setting prediction resistance
+ *
+ * return: flags
+ */
+static inline void drbg_convert_tfm_core(const char *cra_name,
+ int *coreref, bool *pr)
+{
+ int i = 0;
+ size_t start = 0;
+ int len = 0;
+
+ *pr = true;
+ /* disassemble the names */
+ if (0 == memcmp(cra_name, "drbg(nopr(", 10)) {
+ start = 10;
+ *pr = false;
+ } else if (0 == memcmp(cra_name, "drbg(pr(", 8)) {
+ start = 8;
+ } else {
+ return;
+ }
+
+ /* remove the first part and the closing parenthesis */
+ len = strlen(cra_name) - start - 2;
+ for (i = 0; ARRAY_SIZE(cores) > i; i++) {
+ if (0 == memcmp(cra_name + start, cores[i].cra_name, len)) {
+ *coreref = i;
+ return;
+ }
+ }
+}
+
+/*
+ * Initialize one DRBG invoked by the kernel crypto API
+ *
+ * Function uses the kernel crypto API cra_name to look up
+ * the flags to instantiate the DRBG
+ */
+static int drbg_kcapi_init(struct crypto_tfm *tfm)
+{
+ struct drbg_state *drbg = crypto_tfm_ctx(tfm);
+ bool pr = false;
+ int coreref = 0;
+
+ drbg_convert_tfm_core(crypto_tfm_alg_name(tfm), &coreref, &pr);
+ /* when personalization string is needed, the caller must call reset
+ * and provide the personalization string as seed information */
+ return drbg_instantiate(drbg, NULL, coreref, pr);
+}
+
+static void drbg_kcapi_cleanup(struct crypto_tfm *tfm)
+{
+ drbg_uninstantiate(crypto_tfm_ctx(tfm));
+}
+
+/*
+ * Generate random numbers invoked by the kernel crypto API:
+ * The API of the kernel crypto API is extended as follows:
+ *
+ * If dlen is larger than zero, rdata is interpreted as the output buffer
+ * where random data is to be stored.
+ *
+ * If dlen is zero, rdata is interpreted as a pointer to a struct drbg_gen
+ * which holds the additional information string that is used for the
+ * DRBG generation process. The output buffer that is to be used to store
+ * data is also pointed to by struct drbg_gen.
+ *
+ */
+static int drbg_kcapi_random(struct crypto_rng *tfm, u8 *rdata,
+ unsigned int dlen)
+{
+ struct drbg_state *drbg = crypto_rng_ctx(tfm);
+ if (0 < dlen) {
+ return drbg_generate_long(drbg, rdata, dlen, NULL);
+ } else {
+ struct drbg_gen *data = (struct drbg_gen *)rdata;
+ /* catch NULL pointer */
+ if (!data)
+ return 0;
+ drbg_set_testdata(drbg, data->test_data);
+ return drbg_generate_long(drbg, data->outbuf, data->outlen,
+ data->addtl);
+ }
+}
+
+/*
+ * Reset the DRBG invoked by the kernel crypto API
+ * The reset implies a full re-initialization of the DRBG. Similar to the
+ * generate function of drbg_kcapi_random, this function extends the
+ * kernel crypto API interface with struct drbg_gen
+ */
+static int drbg_kcapi_reset(struct crypto_rng *tfm, u8 *seed, unsigned int slen)
+{
+ struct drbg_state *drbg = crypto_rng_ctx(tfm);
+ struct crypto_tfm *tfm_base = crypto_rng_tfm(tfm);
+ bool pr = false;
+ struct drbg_string seed_string;
+ int coreref = 0;
+
+ drbg_uninstantiate(drbg);
+ drbg_convert_tfm_core(crypto_tfm_alg_name(tfm_base), &coreref, &pr);
+ if (0 < slen) {
+ drbg_string_fill(&seed_string, seed, slen);
+ return drbg_instantiate(drbg, &seed_string, coreref, pr);
+ } else {
+ struct drbg_gen *data = (struct drbg_gen *)seed;
+ /* allow invocation of API call with NULL, 0 */
+ if (!data)
+ return drbg_instantiate(drbg, NULL, coreref, pr);
+ drbg_set_testdata(drbg, data->test_data);
+ return drbg_instantiate(drbg, data->addtl, coreref, pr);
+ }
+}
+
+/***************************************************************
+ * Kernel module: code to load the module
+ ***************************************************************/
+
+/*
+ * Tests as defined in 11.3.2 in addition to the cipher tests: testing
+ * of the error handling.
+ *
+ * Note, testing of failing seed source as defined in 11.3.2 is not applicable
+ * as seed source of get_random_bytes does not fail.
+ * Note, testing the reseed counter is not done as an automatic reseeding
+ * is performed in drbg_generate when the reseed counter is too large.
+ */
+static inline int __init drbg_healthcheck_sanity(void)
+{
+#ifdef CONFIG_CRYPTO_FIPS
+ unsigned int len = 0;
+#define OUTBUFLEN 16
+ unsigned char buf[OUTBUFLEN];
+ struct drbg_state *drbg = NULL;
+ int ret = -EFAULT;
+ int rc = -EFAULT;
+ bool pr = false;
+ int coreref = 0;
+ struct drbg_string addtl;
+ size_t max_addtllen, max_request_bytes;
+
+ /* only perform test in FIPS mode */
+ if (0 == fips_enabled)
+ return 0;
+
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+ drbg_convert_tfm_core("drbg(nopr(ctr(aes128)))", &coreref, &pr);
+#elif CONFIG_CRYPTO_DRBG_HASH
+ drbg_convert_tfm_core("drbg(nopr(sha256)", &coreref, &pr);
+#else
+ drbg_convert_tfm_core("drbg(nopr(hmac(sha256)))", &coreref, &pr);
+#endif
+
+ drbg = kzalloc(sizeof(struct drbg_state), GFP_KERNEL);
+ if (!drbg)
+ return -ENOMEM;
+
+ /* if the following tests fail, it is likely that there is a buffer
+ * overflow as buf is much smaller than the requested or provided
+ * string lengths -- in case the error handling does not succeed
+ * we may get an OOPS. And we want to get an OOPS as this is a
+ * grave bug */
+
+ /* get a valid instance of DRBG for following tests */
+ ret = drbg_instantiate(drbg, NULL, coreref, pr);
+ if (ret) {
+ rc = ret;
+ goto outbuf;
+ }
+ max_addtllen = drbg_max_addtl(drbg);
+ max_request_bytes = drbg_max_request_bytes(drbg);
+ drbg_string_fill(&addtl, buf, max_addtllen + 1);
+ /* overflow addtllen with additonal info string */
+ len = drbg_generate(drbg, buf, OUTBUFLEN, &addtl);
+ BUG_ON(0 < len);
+ /* overflow max_bits */
+ len = drbg_generate(drbg, buf, (max_request_bytes + 1), NULL);
+ BUG_ON(0 < len);
+ drbg_uninstantiate(drbg);
+
+ /* overflow max addtllen with personalization string */
+ ret = drbg_instantiate(drbg, &addtl, coreref, pr);
+ BUG_ON(0 == ret);
+ /* test uninstantated DRBG */
+ len = drbg_generate(drbg, buf, (max_request_bytes + 1), NULL);
+ BUG_ON(0 < len);
+ /* all tests passed */
+ rc = 0;
+
+ pr_devel("DRBG: Sanity tests for failure code paths successfully "
+ "completed\n");
+outdrbg:
+ drbg_uninstantiate(drbg);
+outbuf:
+ kzfree(drbg);
+ return rc;
+#else /* CONFIG_CRYPTO_FIPS */
+ return 0;
+#endif /* CONFIG_CRYPTO_FIPS */
+}
+
+
+static struct crypto_alg drbg_algs[22];
+
+/*
+ * Fill the array drbg_algs used to register the different DRBGs
+ * with the kernel crypto API. To fill the array, the information
+ * from cores[] is used.
+ */
+static inline void __init drbg_fill_array(unsigned long i, unsigned long j,
+ int pr)
+{
+ int pos = 0;
+
+ memset(&drbg_algs[i], 0, sizeof(struct crypto_alg));
+ if (pr) {
+ memcpy(drbg_algs[i].cra_name, "drbg(pr(", 8);
+ memcpy(drbg_algs[i].cra_driver_name, "drbg_pr_", 8);
+ pos = 8;
+ } else {
+ memcpy(drbg_algs[i].cra_name, "drbg(nopr(", 10);
+ memcpy(drbg_algs[i].cra_driver_name, "drbg_nopr_", 10);
+ pos = 10;
+ }
+ memcpy(drbg_algs[i].cra_name + pos, cores[j].cra_name,
+ strlen(cores[j].cra_name));
+ memcpy(drbg_algs[i].cra_name + pos + strlen(cores[j].cra_name), "))",
+ 2);
+ memcpy(drbg_algs[i].cra_driver_name + pos,
+ cores[j].cra_driver_name, strlen(cores[j].cra_driver_name));
+ drbg_algs[i].cra_priority = 100;
+ drbg_algs[i].cra_flags = CRYPTO_ALG_TYPE_RNG;
+ drbg_algs[i].cra_ctxsize = sizeof(struct drbg_state);
+ drbg_algs[i].cra_type = &crypto_rng_type;
+ drbg_algs[i].cra_module = THIS_MODULE;
+ drbg_algs[i].cra_init = drbg_kcapi_init;
+ drbg_algs[i].cra_exit = drbg_kcapi_cleanup;
+ drbg_algs[i].cra_u.rng.rng_make_random = drbg_kcapi_random;
+ drbg_algs[i].cra_u.rng.rng_reset = drbg_kcapi_reset;
+ drbg_algs[i].cra_u.rng.seedsize = 0;
+}
+
+static int __init drbg_init(void)
+{
+ unsigned int i = 0; /* pointer to drbg_algs */
+ unsigned int j = 0; /* pointer to cores */
+ int ret = -EFAULT;
+
+ ret = drbg_healthcheck_sanity();
+ if (ret)
+ return ret;
+
+ if (ARRAY_SIZE(cores) * 2 > ARRAY_SIZE(drbg_algs))
+ pr_info("DRBG: Not all available DRBGs registered"
+ "(slots needed: %lu, slots available: %lu)\n",
+ ARRAY_SIZE(cores) * 2, ARRAY_SIZE(drbg_algs));
+
+ /* each DRBG definition can be used with PR and without PR, thus
+ * we instantiate each DRBG in cores[] twice */
+ for (j = 0; ARRAY_SIZE(cores) > j; j++) {
+ drbg_fill_array(i, j, 1);
+ i++;
+ drbg_fill_array(i, j, 0);
+ i++;
+ }
+ return crypto_register_algs(drbg_algs, (ARRAY_SIZE(cores) * 2));
+}
+
+void __exit drbg_exit(void)
+{
+ crypto_unregister_algs(drbg_algs, (ARRAY_SIZE(cores) * 2));
+}
+
+module_init(drbg_init);
+module_exit(drbg_exit);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Stephan Mueller <smueller@chronox.de>");
+MODULE_DESCRIPTION("NIST SP800-90A Deterministic Random Bit Generator (DRBG) using following cores:"
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+"HMAC "
+#endif
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+"Hash "
+#endif
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+"CTR"
+#endif
+);
^ permalink raw reply related [flat|nested] 29+ messages in thread* Re: [PATCH v4 1/6] SP800-90A Deterministic Random Bit Generator
2014-04-11 18:07 ` [PATCH v4 " Stephan Mueller
@ 2014-04-11 18:20 ` Joe Perches
2014-04-11 19:24 ` Stephan Mueller
2014-04-15 5:35 ` [PATCH v5 " Stephan Mueller
1 sibling, 1 reply; 29+ messages in thread
From: Joe Perches @ 2014-04-11 18:20 UTC (permalink / raw)
To: Stephan Mueller
Cc: linux-kernel, linux-crypto, aquini, jeremy.wayne.powell, clemens,
pwalten
On Fri, 2014-04-11 at 20:07 +0200, Stephan Mueller wrote:
> Changes v4:
> * change return codes of generate functions to signed int to convey error
> codes and to match the kernel crypto API expecations on the generate
> function.
> * add BUG_ON throughout drbg_healthcheck_sanity() since any failure should
> should be caugth to prevent the DRBG from operating
> * change layout of debugging printk
It looks like const could be used a bit more often.
For instance:
perhaps uses of key could be changed to const unsigned char *key
> diff --git a/crypto/drbg.c b/crypto/drbg.c
[]
> +#ifdef CONFIG_CRYPTO_DRBG_CTR
> +static int drbg_kcapi_sym(struct drbg_state *drbg, unsigned char *key,
> + unsigned char *outval, struct drbg_string *in);
[]
> +/* BCC function for CTR DRBG as defined in 10.4.3 */
> +static int drbg_ctr_bcc(struct drbg_state *drbg,
> + unsigned char *out, unsigned char *key,
> + struct drbg_string *in)
[]
> +/* Derivation Function for CTR DRBG as defined in 10.4.2 */
> +static int drbg_ctr_df(struct drbg_state *drbg,
> + unsigned char *df_data, size_t bytes_to_return,
> + struct drbg_string *addtl)
> +{
[]
> + unsigned char *K = (unsigned char *)
> + "\x00\x01\x02\x03\x04\x05\x06\x07"
> + "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f"
> + "\x10\x11\x12\x13\x14\x15\x16\x17"
> + "\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f";
^ permalink raw reply [flat|nested] 29+ messages in thread* Re: [PATCH v4 1/6] SP800-90A Deterministic Random Bit Generator
2014-04-11 18:20 ` Joe Perches
@ 2014-04-11 19:24 ` Stephan Mueller
0 siblings, 0 replies; 29+ messages in thread
From: Stephan Mueller @ 2014-04-11 19:24 UTC (permalink / raw)
To: Joe Perches
Cc: linux-kernel, linux-crypto, aquini, jeremy.wayne.powell, clemens,
pwalten
Am Freitag, 11. April 2014, 11:20:21 schrieb Joe Perches:
Hi Joe,
>
> It looks like const could be used a bit more often.
>
> For instance:
> perhaps uses of key could be changed to const unsigned char *key
Good point. I will try to find areas where const can be used. However, due to
the use of a linked list approach with struct drbg_string, using const will
remain limited.
Ciao
Stephan
--
| Cui bono? |
^ permalink raw reply [flat|nested] 29+ messages in thread
* [PATCH v5 1/6] SP800-90A Deterministic Random Bit Generator
2014-04-11 18:07 ` [PATCH v4 " Stephan Mueller
2014-04-11 18:20 ` Joe Perches
@ 2014-04-15 5:35 ` Stephan Mueller
2014-04-15 5:51 ` Joe Perches
2014-04-26 20:13 ` [PATCH v6 " Stephan Mueller
1 sibling, 2 replies; 29+ messages in thread
From: Stephan Mueller @ 2014-04-15 5:35 UTC (permalink / raw)
To: linux-kernel, linux-crypto
Cc: aquini, jeremy.wayne.powell, clemens, pwalten, joe
Changes v5:
* make numerous character buffer pointers and drbg_string pointers const
as suggested by Joe Perches
Signed-off-by: Stephan Mueller <smueller@chronox.de>
---
create mode 100644 crypto/drbg.c
diff --git a/crypto/drbg.c b/crypto/drbg.c
new file mode 100644
index 0000000..1097d13
--- /dev/null
+++ b/crypto/drbg.c
@@ -0,0 +1,1997 @@
+/*
+ * DRBG: Deterministic Random Bits Generator
+ * Based on NIST Recommended DRBG from NIST SP800-90A with the following
+ * properties:
+ * * CTR DRBG with DF with AES-128, AES-192, AES-256 cores
+ * * Hash DRBG with DF with SHA-1, SHA-256, SHA-384, SHA-512 cores
+ * * HMAC DRBG with DF with SHA-1, SHA-256, SHA-384, SHA-512 cores
+ * * with and without prediction resistance
+ *
+ * Copyright Stephan Mueller <smueller@chronox.de>, 2014
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, and the entire permission notice in its entirety,
+ * including the disclaimer of warranties.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote
+ * products derived from this software without specific prior
+ * written permission.
+ *
+ * ALTERNATIVELY, this product may be distributed under the terms of
+ * the GNU General Public License, in which case the provisions of the GPL are
+ * required INSTEAD OF the above restrictions. (This clause is
+ * necessary due to a potential bad interaction between the GPL and
+ * the restrictions contained in a BSD-style copyright.)
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF
+ * WHICH ARE HEREBY DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+ * USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * DRBG Usage
+ * ==========
+ * The SP 800-90A DRBG allows the user to specify a personalization string
+ * for initialization as well as an additional information string for each
+ * random number request. The following code fragments show how a caller
+ * uses the kernel crypto API to use the full functionality of the DRBG.
+ *
+ * Usage without any additional data
+ * ---------------------------------
+ * struct crypto_rng *drng;
+ * int err;
+ * char data[DATALEN];
+ *
+ * drng = crypto_alloc_rng(drng_name, 0, 0);
+ * err = crypto_rng_get_bytes(drng, &data, DATALEN);
+ * crypto_free_rng(drng);
+ *
+ *
+ * Usage with personalization string during initialization
+ * -------------------------------------------------------
+ * struct crypto_rng *drng;
+ * int err;
+ * char data[DATALEN];
+ * struct drbg_string pers;
+ * char personalization[11] = "some-string";
+ *
+ * drbg_string_fill(&pers, personalization, strlen(personalization));
+ * drng = crypto_alloc_rng(drng_name, 0, 0);
+ * // The reset completely re-initializes the DRBG with the provided
+ * // personalization string
+ * err = crypto_rng_reset(drng, &personalization, strlen(personalization));
+ * err = crypto_rng_get_bytes(drng, &data, DATALEN);
+ * crypto_free_rng(drng);
+ *
+ *
+ * Usage with additional information string during random number request
+ * ---------------------------------------------------------------------
+ * struct crypto_rng *drng;
+ * int err;
+ * char data[DATALEN];
+ * char addtl_string[11] = "some-string";
+ * string drbg_string addtl;
+ *
+ * drbg_string_fill(&addtl, addtl_string, strlen(addtl_string));
+ * drng = crypto_alloc_rng(drng_name, 0, 0);
+ * // The following call is a wrapper to crypto_rng_get_bytes() and returns
+ * // the same error codes.
+ * err = crypto_drbg_get_bytes_addtl(drng, &data, DATALEN, &addtl);
+ * crypto_free_rng(drng);
+ *
+ *
+ * Usage with personalization and additional information strings
+ * -------------------------------------------------------------
+ * Just mix both scenarios above.
+ */
+
+#include <crypto/drbg.h>
+
+#if !defined(CONFIG_CRYPTO_DRBG_HASH) && \
+ !defined(CONFIG_CRYPTO_DRBG_HMAC) && \
+ !defined(CONFIG_CRYPTO_DRBG_CTR)
+#warning "The DRBG code is useless without compiling at least one DRBG type"
+#endif
+
+/***************************************************************
+ * Backend cipher definitions available to DRBG
+ ***************************************************************/
+
+const struct drbg_core cores[] = {
+ /* Hash DRBGs */
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+ {
+ .flags = DRBG_HASH | DRBG_STRENGTH128,
+ .statelen = 55, /* 440 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 20,
+ .cra_name = "sha1",
+ .cra_driver_name = "sha1",
+ .backend_cra_name = "sha1",
+ }, {
+ .flags = DRBG_HASH | DRBG_STRENGTH256,
+ .statelen = 55, /* 440 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 32,
+ .cra_name = "sha256",
+ .cra_driver_name = "sha256",
+ .backend_cra_name = "sha256",
+ }, {
+ .flags = DRBG_HASH | DRBG_STRENGTH256,
+ .statelen = 111, /* 888 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 48,
+ .cra_name = "sha384",
+ .cra_driver_name = "sha384",
+ .backend_cra_name = "sha384",
+ }, {
+ .flags = DRBG_HASH | DRBG_STRENGTH256,
+ .statelen = 111, /* 888 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 64,
+ .cra_name = "sha512",
+ .cra_driver_name = "sha512",
+ .backend_cra_name = "sha512",
+ },
+#endif /* CONFIG_CRYPTO_DRBG_HASH */
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+ {
+ /* HMAC DRBGs */
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 20, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 20,
+ .cra_name = "hmac(sha1)",
+ .cra_driver_name = "hmac_sha1",
+ .backend_cra_name = "hmac(sha1)",
+ }, {
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 32, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 32,
+ .cra_name = "hmac(sha256)",
+ .cra_driver_name = "hmac_sha256",
+ .backend_cra_name = "hmac(sha256)",
+ }, {
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 48, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 48,
+ .cra_name = "hmac(sha384)",
+ .cra_driver_name = "hmac_sha384",
+ .backend_cra_name = "hmac(sha384)",
+ }, {
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 64, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 64,
+ .cra_name = "hmac(sha512)",
+ .cra_driver_name = "hmac_sha512",
+ .backend_cra_name = "hmac(sha512)",
+ },
+#endif /* CONFIG_CRYPTO_DRBG_HMAC */
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+ {
+ /* block ciphers */
+ .flags = DRBG_CTR | DRBG_STRENGTH128,
+ .statelen = 32, /* 256 bits as defined in 10.2.1 */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 16,
+ .cra_name = "ctr(aes128)",
+ .cra_driver_name = "ctr_aes128",
+ .backend_cra_name = "ecb(aes)",
+ }, {
+ /* block ciphers */
+ .flags = DRBG_CTR | DRBG_STRENGTH192,
+ .statelen = 40, /* 320 bits as defined in 10.2.1 */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 16,
+ .cra_name = "ctr(aes192)",
+ .cra_driver_name = "ctr_aes192",
+ .backend_cra_name = "ecb(aes)",
+ }, {
+ /* block ciphers */
+ .flags = DRBG_CTR | DRBG_STRENGTH256,
+ .statelen = 48, /* 384 bits as defined in 10.2.1 */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 16,
+ .cra_name = "ctr(aes256)",
+ .cra_driver_name = "ctr_aes256",
+ .backend_cra_name = "ecb(aes)",
+ },
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+};
+
+/******************************************************************
+ * Generic helper functions
+ ******************************************************************/
+
+/*
+ * Return strength of DRBG according to SP800-90A section 8.4
+ *
+ * @flags DRBG flags reference
+ *
+ * Return: normalized strength in *bytes* value or 32 as default
+ * to counter programming errors
+ */
+static inline unsigned short drbg_sec_strength(drbg_flag_t flags)
+{
+ switch (flags & DRBG_STRENGTH_MASK) {
+ case DRBG_STRENGTH128:
+ return 16;
+ case DRBG_STRENGTH192:
+ return 24;
+ case DRBG_STRENGTH256:
+ return 32;
+ default:
+ return 32;
+ }
+}
+
+/*
+ * FIPS 140-2 continuous self test
+ * The test is performed on the result of one round of the output
+ * function. Thus, the function implicitly knows the size of the
+ * buffer.
+ *
+ * The FIPS test can be called in an endless loop until it returns
+ * true. Although the code looks like a potential for a deadlock, it
+ * is not the case, because returning a false cannot mathematically
+ * occur (except once when a reseed took place and the updated state
+ * would is now set up such that the generation of new value returns
+ * an identical one -- this is most unlikely and would happen only once).
+ * Thus, if this function repeatedly returns false and thus would cause
+ * a deadlock, the integrity of the entire kernel is lost.
+ *
+ * @drbg DRBG handle
+ * @buf output buffer of random data to be checked
+ *
+ * return:
+ * true on success
+ * false on error
+ */
+static bool drbg_fips_continuous_test(struct drbg_state *drbg,
+ const unsigned char *buf)
+{
+#ifdef CONFIG_CRYPTO_FIPS
+ int ret = 0;
+ /* skip test if we test the overall system */
+ if (drbg->test_data)
+ return true;
+ /* only perform test in FIPS mode */
+ if (0 == fips_enabled)
+ return true;
+ if (!drbg->fips_primed) {
+ /* Priming of FIPS test */
+ memcpy(drbg->prev, buf, drbg_blocklen(drbg));
+ drbg->fips_primed = true;
+ /* return false due to priming, i.e. another round is needed */
+ return false;
+ }
+ ret = memcmp(drbg->prev, buf, drbg_blocklen(drbg));
+ memcpy(drbg->prev, buf, drbg_blocklen(drbg));
+ /* the test shall pass when the two compared values are not equal */
+ return ret != 0;
+#else
+ return true;
+#endif /* CONFIG_CRYPTO_FIPS */
+}
+
+/*
+ * Convert an integer into a byte representation of this integer.
+ * The byte representation is big-endian
+ *
+ * @buf buffer holding the converted integer
+ * @val value to be converted
+ * @buflen length of buffer
+ */
+#if (defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_CTR))
+static inline void drbg_int2byte(unsigned char *buf, uint64_t val,
+ size_t buflen)
+{
+ unsigned char *byte;
+ uint64_t i;
+
+ byte = buf + (buflen - 1);
+ for (i = 0; i < buflen; i++)
+ *(byte--) = val >> (i * 8) & 0xff;
+}
+
+/*
+ * Increment buffer
+ *
+ * @dst buffer to increment
+ * @add value to add
+ */
+static inline void drbg_add_buf(unsigned char *dst, size_t dstlen,
+ const unsigned char *add, size_t addlen)
+{
+ /* implied: dstlen > addlen */
+ unsigned char *dstptr;
+ const unsigned char *addptr;
+ unsigned int remainder = 0;
+ size_t len = addlen;
+
+ dstptr = dst + (dstlen-1);
+ addptr = add + (addlen-1);
+ while (len) {
+ remainder += *dstptr + *addptr;
+ *dstptr = remainder & 0xff;
+ remainder >>= 8;
+ len--; dstptr--; addptr--;
+ }
+ len = dstlen - addlen;
+ while (len && remainder > 0) {
+ remainder = *dstptr + 1;
+ *dstptr = remainder & 0xff;
+ remainder >>= 8;
+ len--; dstptr--;
+ }
+}
+#endif /* defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_CTR) */
+
+/******************************************************************
+ * CTR DRBG callback functions
+ ******************************************************************/
+
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+static int drbg_kcapi_sym(struct drbg_state *drbg, const unsigned char *key,
+ unsigned char *outval, const struct drbg_string *in);
+static int drbg_init_sym_kernel(struct drbg_state *drbg);
+static int drbg_fini_sym_kernel(struct drbg_state *drbg);
+
+/* BCC function for CTR DRBG as defined in 10.4.3 */
+static int drbg_ctr_bcc(struct drbg_state *drbg,
+ unsigned char *out, const unsigned char *key,
+ struct drbg_string *in)
+{
+ int ret = -EFAULT;
+ struct drbg_string *curr = in;
+ size_t inpos = curr->len;
+ const unsigned char *pos = curr->buf;
+ struct drbg_string data;
+
+ drbg_string_fill(&data, out, drbg_blocklen(drbg));
+
+ /* 10.4.3 step 1 */
+ memset(out, 0, drbg_blocklen(drbg));
+
+ /* 10.4.3 step 2 / 4 */
+ while (inpos) {
+ short cnt = 0;
+ /* 10.4.3 step 4.1 */
+ for (cnt = 0; cnt < drbg_blocklen(drbg); cnt++) {
+ out[cnt] ^= *pos;
+ pos++; inpos--;
+ /* the following branch implements the linked list
+ * iteration. If we are at the end of the current data
+ * set, we have to start using the next data set if
+ * available -- the inpos value always points to the
+ * current byte and will be zero if we have processed
+ * the last byte of the last linked list member */
+ if (0 == inpos) {
+ curr = curr->next;
+ if (NULL != curr) {
+ pos = curr->buf;
+ inpos = curr->len;
+ } else {
+ inpos = 0;
+ break;
+ }
+ }
+ }
+ /* 10.4.3 step 4.2 */
+ ret = drbg_kcapi_sym(drbg, key, out, &data);
+ if (ret)
+ return ret;
+ /* 10.4.3 step 2 */
+ }
+ return 0;
+}
+
+/*
+ * scratchpad usage: drbg_ctr_update is interlinked with drbg_ctr_df
+ * (and drbg_ctr_bcc, but this function does not need any temporary buffers),
+ * the scratchpad is used as follows:
+ * drbg_ctr_update:
+ * temp
+ * start: drbg->scratchpad
+ * length: drbg_statelen(drbg) + drbg_blocklen(drbg)
+ * note: the cipher writing into this variable works
+ * blocklen-wise. Now, when the statelen is not a multiple
+ * of blocklen, the generateion loop below "spills over"
+ * by at most blocklen. Thus, we need to give sufficient
+ * memory.
+ * df_data
+ * start: drbg->scratchpad +
+ * drbg_statelen(drbg) + drbg_blocklen(drbg)
+ * length: drbg_statelen(drbg)
+ *
+ * drbg_ctr_df:
+ * pad
+ * start: df_data + drbg_statelen(drbg)
+ * length: drbg_blocklen(drbg)
+ * iv
+ * start: pad + drbg_blocklen(drbg)
+ * length: drbg_blocklen(drbg)
+ * temp
+ * start: iv + drbg_blocklen(drbg)
+ * length: (drbg_keylen(drbg) + drbg_blocklen(drbg) ==
+ * drbg_statelen(drbg))
+ */
+
+/* Derivation Function for CTR DRBG as defined in 10.4.2 */
+static int drbg_ctr_df(struct drbg_state *drbg,
+ unsigned char *df_data, size_t bytes_to_return,
+ struct drbg_string *addtl)
+{
+ int ret = -EFAULT;
+ unsigned char L_N[8];
+ /* S3 is input */
+ struct drbg_string S1, S2, S4, cipherin;
+ struct drbg_string *tempstr = addtl;
+ unsigned char *pad = df_data + drbg_statelen(drbg);
+ unsigned char *iv = pad + drbg_blocklen(drbg);
+ unsigned char *temp = iv + drbg_blocklen(drbg);
+ size_t padlen = 0;
+ unsigned int templen = 0;
+ /* 10.4.2 step 7 */
+ unsigned int i = 0;
+ /* 10.4.2 step 8 */
+ const unsigned char *K = (unsigned char *)
+ "\x00\x01\x02\x03\x04\x05\x06\x07"
+ "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f"
+ "\x10\x11\x12\x13\x14\x15\x16\x17"
+ "\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f";
+ unsigned char *X;
+ size_t generated_len = 0;
+ size_t inputlen = 0;
+
+ memset(pad, 0, drbg_blocklen(drbg));
+ memset(iv, 0, drbg_blocklen(drbg));
+ memset(temp, 0, drbg_statelen(drbg));
+
+ /* 10.4.2 step 1 is implicit as we work byte-wise */
+
+ /* 10.4.2 step 2 */
+ if ((512/8) < bytes_to_return)
+ return -EINVAL;
+
+ /* 10.4.2 step 2 -- calculate the entire length of all input data */
+ for (; NULL != tempstr; tempstr = tempstr->next)
+ inputlen += tempstr->len;
+ drbg_int2byte(&L_N[0], inputlen, 4);
+
+ /* 10.4.2 step 3 */
+ drbg_int2byte(&L_N[4], bytes_to_return, 4);
+
+ /* 10.4.2 step 5: length is L_N, input_string, one byte, padding */
+ padlen = (inputlen + sizeof(L_N) + 1) % (drbg_blocklen(drbg));
+ /* wrap the padlen appropriately */
+ if (padlen)
+ padlen = drbg_blocklen(drbg) - padlen;
+ /* pad / padlen contains the 0x80 byte and the following zero bytes, so
+ * add one for byte for 0x80 */
+ padlen++;
+ pad[0] = 0x80;
+
+ /* 10.4.2 step 4 -- first fill the linked list and then order it */
+ drbg_string_fill(&S1, iv, drbg_blocklen(drbg));
+ drbg_string_fill(&S2, L_N, sizeof(L_N));
+ drbg_string_fill(&S4, pad, padlen);
+ S1.next = &S2;
+ S2.next = addtl;
+ /* splice in addtl between S2 and S4 -- we place S4 at the end of the
+ * input data chain */
+ tempstr = addtl;
+ for (; NULL != tempstr; tempstr = tempstr->next)
+ if (NULL == tempstr->next)
+ break;
+ tempstr->next = &S4;
+
+ /* 10.4.2 step 9 */
+ while (templen < (drbg_keylen(drbg) + (drbg_blocklen(drbg)))) {
+ /* 10.4.2 step 9.1 - the padding is implicit as the buffer
+ * holds zeros after allocation -- even the increment of i
+ * is irrelevant as the increment remains within length of i */
+ drbg_int2byte(iv, i, 4);
+ /* 10.4.2 step 9.2 -- BCC and concatenation with temp */
+ ret = drbg_ctr_bcc(drbg, temp + templen, K, &S1);
+ if (ret)
+ goto out;
+ /* 10.4.2 step 9.3 */
+ i++;
+ templen += drbg_blocklen(drbg);
+ }
+
+ /* 10.4.2 step 11 */
+ /* implicit key len with seedlen - blocklen according to table 3 */
+ X = temp + (drbg_keylen(drbg));
+ drbg_string_fill(&cipherin, X, drbg_blocklen(drbg));
+
+ /* 10.4.2 step 12: overwriting of outval */
+
+ /* 10.4.2 step 13 */
+ while (generated_len < bytes_to_return) {
+ short blocklen = 0;
+ /* 10.4.2 step 13.1 */
+ /* the truncation of the key length is implicit as the key
+ * is only drbg_blocklen in size -- check for the implementation
+ * of the cipher function callback */
+ ret = drbg_kcapi_sym(drbg, temp, X, &cipherin);
+ if (ret)
+ goto out;
+ blocklen = (drbg_blocklen(drbg) <
+ (bytes_to_return - generated_len)) ?
+ drbg_blocklen(drbg) :
+ (bytes_to_return - generated_len);
+ /* 10.4.2 step 13.2 and 14 */
+ memcpy(df_data + generated_len, X, blocklen);
+ generated_len += blocklen;
+ }
+
+ ret = 0;
+
+out:
+ memset(iv, 0, drbg_blocklen(drbg));
+ memset(temp, 0, drbg_statelen(drbg));
+ memset(pad, 0, drbg_blocklen(drbg));
+ return ret;
+}
+
+/* update function of CTR DRBG as defined in 10.2.1.2 */
+static int drbg_ctr_update(struct drbg_state *drbg,
+ struct drbg_string *addtl, int reseed)
+{
+ int ret = -EFAULT;
+ /* 10.2.1.2 step 1 */
+ unsigned char *temp = drbg->scratchpad;
+ unsigned char *df_data = drbg->scratchpad + drbg_statelen(drbg) +
+ drbg_blocklen(drbg);
+ unsigned char *temp_p, *df_data_p; /* pointer to iterate over buffers */
+ unsigned int len = 0;
+ struct drbg_string cipherin;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ memset(temp, 0, drbg_statelen(drbg) + drbg_blocklen(drbg));
+ memset(df_data, 0, drbg_statelen(drbg));
+
+ /* 10.2.1.3.2 step 2 and 10.2.1.4.2 step 2 */
+ if (addtl && 0 < addtl->len) {
+ ret = drbg_ctr_df(drbg, df_data, drbg_statelen(drbg),
+ addtl);
+ if (ret)
+ goto out;
+ }
+
+ drbg_string_fill(&cipherin, drbg->V, drbg_blocklen(drbg));
+ /* 10.2.1.3.2 step 2 and 3 -- are already covered as we memset(0)
+ * all memory during initialization */
+ while (len < (drbg_statelen(drbg))) {
+ /* 10.2.1.2 step 2.1 */
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ /* 10.2.1.2 step 2.2 */
+ /* using target of temp + len: 10.2.1.2 step 2.3 and 3 */
+ ret = drbg_kcapi_sym(drbg, drbg->C, temp + len, &cipherin);
+ if (ret)
+ goto out;
+ /* 10.2.1.2 step 2.3 and 3 */
+ len += drbg_blocklen(drbg);
+ }
+
+ /* 10.2.1.2 step 4 */
+ temp_p = temp;
+ df_data_p = df_data;
+ for (len = 0; len < drbg_statelen(drbg); len++) {
+ *temp_p ^= *df_data_p;
+ df_data_p++; temp_p++;
+ }
+
+ /* 10.2.1.2 step 5 */
+ memcpy(drbg->C, temp, drbg_keylen(drbg));
+ /* 10.2.1.2 step 6 */
+ memcpy(drbg->V, temp + drbg_keylen(drbg), drbg_blocklen(drbg));
+ ret = 0;
+
+out:
+ memset(temp, 0, drbg_statelen(drbg) + drbg_blocklen(drbg));
+ memset(df_data, 0, drbg_statelen(drbg));
+ return ret;
+}
+
+/*
+ * scratchpad use: drbg_ctr_update is called independently from
+ * drbg_ctr_extract_bytes. Therefore, the scratchpad is reused
+ */
+/* Generate function of CTR DRBG as defined in 10.2.1.5.2 */
+static int drbg_ctr_generate(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ int len = 0;
+ int ret = 0;
+ struct drbg_string data;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+
+ /* 10.2.1.5.2 step 2 */
+ if (addtl && 0 < addtl->len) {
+ addtl->next = NULL;
+ ret = drbg_ctr_update(drbg, addtl, 1);
+ if (ret)
+ return 0;
+ }
+
+ /* 10.2.1.5.2 step 4.1 */
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ drbg_string_fill(&data, drbg->V, drbg_blocklen(drbg));
+ while (len < buflen) {
+ int outlen = 0;
+ /* 10.2.1.5.2 step 4.2 */
+ ret = drbg_kcapi_sym(drbg, drbg->C, drbg->scratchpad, &data);
+ if (ret) {
+ len = ret;
+ goto out;
+ }
+ outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
+ drbg_blocklen(drbg) : (buflen - len);
+ if (!drbg_fips_continuous_test(drbg, drbg->scratchpad)) {
+ /* 10.2.1.5.2 step 6 */
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ continue;
+ }
+ /* 10.2.1.5.2 step 4.3 */
+ memcpy(buf + len, drbg->scratchpad, outlen);
+ len += outlen;
+ /* 10.2.1.5.2 step 6 */
+ if (len < buflen)
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ }
+
+ /* 10.2.1.5.2 step 6 */
+ /*TODO the DF function is called again since according to step
+ * 2, the "additional_input" after step 2 is the output of the DF
+ * function -- when we save the DF output as a replacement
+ * for the addtl_input data, we do not need to call the DF again here */
+ if (addtl)
+ addtl->next = NULL;
+ ret = drbg_ctr_update(drbg, addtl, 1);
+ if (ret)
+ len = ret;
+
+out:
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ return len;
+}
+
+static struct drbg_state_ops drbg_ctr_ops = {
+ .update = drbg_ctr_update,
+ .generate = drbg_ctr_generate,
+ .crypto_init = drbg_init_sym_kernel,
+ .crypto_fini = drbg_fini_sym_kernel,
+};
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+
+/******************************************************************
+ * HMAC DRBG callback functions
+ ******************************************************************/
+
+#if defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_HMAC)
+static int drbg_kcapi_hash(struct drbg_state *drbg, const unsigned char *key,
+ unsigned char *outval, const struct drbg_string *in);
+static int drbg_init_hash_kernel(struct drbg_state *drbg);
+static int drbg_fini_hash_kernel(struct drbg_state *drbg);
+#endif /* (CONFIG_CRYPTO_DRBG_HASH || CONFIG_CRYPTO_DRBG_HMAC) */
+
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+/* update function of HMAC DRBG as defined in 10.1.2.2 */
+static int drbg_hmac_update(struct drbg_state *drbg,
+ struct drbg_string *seed, int reseed)
+{
+ int ret = -EFAULT;
+ int i = 0;
+ struct drbg_string seed1, seed2, cipherin;
+
+ if (!reseed) {
+ /* 10.1.2.3 step 2 already implicitly covered with
+ * the initial memset(0) of drbg->C */
+ memset(drbg->C, 0, drbg_statelen(drbg));
+ memset(drbg->V, 1, drbg_statelen(drbg));
+ }
+
+ /* build linked list which implements the concatenation and fill
+ * first part*/
+ drbg_string_fill(&seed1, drbg->V, drbg_statelen(drbg));
+ /* buffer will be filled in for loop below with one byte */
+ drbg_string_fill(&seed2, NULL, 1);
+ seed1.next = &seed2;
+ /* seed may be NULL */
+ seed2.next = seed;
+
+ drbg_string_fill(&cipherin, drbg->V, drbg_statelen(drbg));
+ /* we execute two rounds of V/K massaging */
+ for (i = 2; 0 < i; i--) {
+ /* first round uses 0x0, second 0x1 */
+ unsigned char prefix = DRBG_PREFIX0;
+ if (1 == i)
+ prefix = DRBG_PREFIX1;
+ /* 10.1.2.2 step 1 and 4 -- concatenation and HMAC for key */
+ seed2.buf = &prefix;
+ ret = drbg_kcapi_hash(drbg, drbg->C, drbg->C, &seed1);
+ if (ret)
+ return ret;
+
+ /* 10.1.2.2 step 2 and 5 -- HMAC for V */
+ ret = drbg_kcapi_hash(drbg, drbg->C, drbg->V, &cipherin);
+ if (ret)
+ return ret;
+
+ /* 10.1.2.2 step 3 */
+ if (!seed || 0 == seed->len)
+ return ret;
+ }
+
+ return 0;
+}
+
+/* generate function of HMAC DRBG as defined in 10.1.2.5 */
+static int drbg_hmac_generate(struct drbg_state *drbg,
+ unsigned char *buf,
+ unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ int len = 0;
+ int ret = 0;
+ struct drbg_string data;
+
+ /* 10.1.2.5 step 2 */
+ if (addtl && 0 < addtl->len) {
+ addtl->next = NULL;
+ ret = drbg_hmac_update(drbg, addtl, 1);
+ if (ret)
+ return ret;
+ }
+
+ drbg_string_fill(&data, drbg->V, drbg_statelen(drbg));
+ while (len < buflen) {
+ unsigned int outlen = 0;
+ /* 10.1.2.5 step 4.1 */
+ ret = drbg_kcapi_hash(drbg, drbg->C, drbg->V, &data);
+ if (ret)
+ return ret;
+ outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
+ drbg_blocklen(drbg) : (buflen - len);
+ if (!drbg_fips_continuous_test(drbg, drbg->V))
+ continue;
+
+ /* 10.1.2.5 step 4.2 */
+ memcpy(buf + len, drbg->V, outlen);
+ len += outlen;
+ }
+
+ /* 10.1.2.5 step 6 */
+ if (addtl)
+ addtl->next = NULL;
+ ret = drbg_hmac_update(drbg, addtl, 1);
+ if (ret)
+ return ret;
+
+ return len;
+}
+
+static struct drbg_state_ops drbg_hmac_ops = {
+ .update = drbg_hmac_update,
+ .generate = drbg_hmac_generate,
+ .crypto_init = drbg_init_hash_kernel,
+ .crypto_fini = drbg_fini_hash_kernel,
+
+};
+#endif /* CONFIG_CRYPTO_DRBG_HMAC */
+
+/******************************************************************
+ * Hash DRBG callback functions
+ ******************************************************************/
+
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+/*
+ * scratchpad usage: as drbg_hash_update and drbg_hash_df are used
+ * interlinked, the scratchpad is used as follows:
+ * drbg_hash_update
+ * start: drbg->scratchpad
+ * length: drbg_statelen(drbg)
+ * drbg_hash_df:
+ * start: drbg->scratchpad + drbg_statelen(drbg)
+ * length: drbg_blocklen(drbg)
+ */
+/* Derivation Function for Hash DRBG as defined in 10.4.1 */
+static int drbg_hash_df(struct drbg_state *drbg,
+ unsigned char *outval, size_t outlen,
+ struct drbg_string *entropy)
+{
+ int ret = 0;
+ size_t len = 0;
+ unsigned char input[5];
+ unsigned char *tmp = drbg->scratchpad + drbg_statelen(drbg);
+ struct drbg_string data1;
+
+ memset(tmp, 0, drbg_blocklen(drbg));
+
+ /* 10.4.1 step 3 */
+ input[0] = 1;
+ drbg_int2byte(&input[1], (outlen * 8), 4);
+
+ /* 10.4.1 step 4.1 -- concatenation of data for input into hash */
+ drbg_string_fill(&data1, input, 5);
+ data1.next = entropy;
+
+ /* 10.4.1 step 4 */
+ while (len < outlen) {
+ short blocklen = 0;
+ /* 10.4.1 step 4.1 */
+ ret = drbg_kcapi_hash(drbg, NULL, tmp, &data1);
+ if (ret)
+ goto out;
+ /* 10.4.1 step 4.2 */
+ input[0]++;
+ blocklen = (drbg_blocklen(drbg) < (outlen - len)) ?
+ drbg_blocklen(drbg) : (outlen - len);
+ memcpy(outval + len, tmp, blocklen);
+ len += blocklen;
+ }
+
+out:
+ memset(tmp, 0, drbg_blocklen(drbg));
+ return ret;
+}
+
+/* update function for Hash DRBG as defined in 10.1.1.2 / 10.1.1.3 */
+static int drbg_hash_update(struct drbg_state *drbg, struct drbg_string *seed,
+ int reseed)
+{
+ int ret = 0;
+ struct drbg_string data1, data2;
+ unsigned char *V = drbg->scratchpad;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ memset(drbg->scratchpad, 0, drbg_statelen(drbg));
+ if (!seed)
+ return -EINVAL;
+
+ if (reseed) {
+ /* 10.1.1.3 step 1: string length is concatenation of
+ * 1 byte, V and seed (which is concatenated entropy/addtl
+ * input)
+ */
+ memcpy(V, drbg->V, drbg_statelen(drbg));
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, V, drbg_statelen(drbg));
+ data1.next = &data2;
+ data2.next = seed;
+ } else {
+ drbg_string_fill(&data1, seed->buf, seed->len);
+ data1.next = seed->next;
+ }
+
+ /* 10.1.1.2 / 10.1.1.3 step 2 and 3 */
+ ret = drbg_hash_df(drbg, drbg->V, drbg_statelen(drbg), &data1);
+ if (ret)
+ goto out;
+
+ /* 10.1.1.2 / 10.1.1.3 step 4 -- concatenation */
+ prefix = DRBG_PREFIX0;
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, drbg->V, drbg_statelen(drbg));
+ data1.next = &data2;
+ /* 10.1.1.2 / 10.1.1.3 step 4 -- df operation */
+ ret = drbg_hash_df(drbg, drbg->C, drbg_statelen(drbg), &data1);
+
+out:
+ memset(drbg->scratchpad, 0, drbg_statelen(drbg));
+ return ret;
+}
+
+/* processing of additional information string for Hash DRBG */
+static int drbg_hash_process_addtl(struct drbg_state *drbg,
+ struct drbg_string *addtl)
+{
+ int ret = 0;
+ struct drbg_string data1, data2;
+ struct drbg_string *data3;
+ unsigned char prefix = DRBG_PREFIX2;
+
+ /* this is value w as per documentation */
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+
+ /* 10.1.1.4 step 2 */
+ if (!addtl || 0 == addtl->len)
+ return 0;
+
+ /* 10.1.1.4 step 2a -- concatenation */
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, drbg->V, drbg_statelen(drbg));
+ data3 = addtl;
+ data1.next = &data2;
+ data2.next = data3;
+ data3->next = NULL;
+ /* 10.1.1.4 step 2a -- cipher invocation */
+ ret = drbg_kcapi_hash(drbg, NULL, drbg->scratchpad, &data1);
+ if (ret)
+ goto out;
+
+ /* 10.1.1.4 step 2b */
+ drbg_add_buf(drbg->V, drbg_statelen(drbg),
+ drbg->scratchpad, drbg_blocklen(drbg));
+
+out:
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ return ret;
+}
+
+/*
+ * Hashgen defined in 10.1.1.4
+ */
+static int drbg_hash_hashgen(struct drbg_state *drbg,
+ unsigned char *buf,
+ unsigned int buflen)
+{
+ int len = 0;
+ int ret = 0;
+ unsigned char *src = drbg->scratchpad;
+ unsigned char *dst = drbg->scratchpad + drbg_statelen(drbg);
+ struct drbg_string data;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ /* use the scratchpad as a lookaside buffer */
+ memset(src, 0, drbg_statelen(drbg));
+ memset(dst, 0, drbg_blocklen(drbg));
+
+ /* 10.1.1.4 step hashgen 2 */
+ memcpy(src, drbg->V, drbg_statelen(drbg));
+
+ drbg_string_fill(&data, src, drbg_statelen(drbg));
+ while (len < buflen) {
+ unsigned int outlen = 0;
+ /* 10.1.1.4 step hashgen 4.1 */
+ ret = drbg_kcapi_hash(drbg, NULL, dst, &data);
+ if (ret) {
+ len = ret;
+ goto out;
+ }
+ outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
+ drbg_blocklen(drbg) : (buflen - len);
+ if (!drbg_fips_continuous_test(drbg, dst)) {
+ drbg_add_buf(src, drbg_statelen(drbg), &prefix, 1);
+ continue;
+ }
+ /* 10.1.1.4 step hashgen 4.2 */
+ memcpy(buf + len, dst, outlen);
+ len += outlen;
+ /* 10.1.1.4 hashgen step 4.3 */
+ if (len < buflen)
+ drbg_add_buf(src, drbg_statelen(drbg), &prefix, 1);
+ }
+
+out:
+ memset(drbg->scratchpad, 0,
+ (drbg_statelen(drbg) + drbg_blocklen(drbg)));
+ return len;
+}
+
+/* generate function for Hash DRBG as defined in 10.1.1.4 */
+static int drbg_hash_generate(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ int len = 0;
+ int ret = 0;
+ unsigned char req[8];
+ unsigned char prefix = DRBG_PREFIX3;
+ struct drbg_string data1, data2;
+
+ /*
+ * scratchpad usage: drbg_hash_process_addtl uses the scratchpad, but
+ * fully completes before returning. Thus, we can reuse the scratchpad
+ */
+ /* 10.1.1.4 step 2 */
+ ret = drbg_hash_process_addtl(drbg, addtl);
+ if (ret)
+ return ret;
+ /* 10.1.1.4 step 3 -- invocation of the Hashgen function defined in
+ * 10.1.1.4 */
+ len = drbg_hash_hashgen(drbg, buf, buflen);
+
+ /* this is the value H as documented in 10.1.1.4 */
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ /* 10.1.1.4 step 4 */
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, drbg->V, drbg_statelen(drbg));
+ data1.next = &data2;
+ ret = drbg_kcapi_hash(drbg, NULL, drbg->scratchpad, &data1);
+ if (ret) {
+ len = ret;
+ goto out;
+ }
+
+ /* 10.1.1.4 step 5 */
+ drbg_add_buf(drbg->V, drbg_statelen(drbg),
+ drbg->scratchpad, drbg_blocklen(drbg));
+ drbg_add_buf(drbg->V, drbg_statelen(drbg),
+ drbg->C, drbg_statelen(drbg));
+ drbg_int2byte(req, drbg->reseed_ctr, sizeof(req));
+ drbg_add_buf(drbg->V, drbg_statelen(drbg), req, 8);
+
+out:
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ return len;
+}
+
+/*
+ * scratchpad usage: as update and generate are used isolated, both
+ * can use the scratchpad
+ */
+static struct drbg_state_ops drbg_hash_ops = {
+ .update = drbg_hash_update,
+ .generate = drbg_hash_generate,
+ .crypto_init = drbg_init_hash_kernel,
+ .crypto_fini = drbg_fini_hash_kernel,
+};
+#endif /* CONFIG_CRYPTO_DRBG_HASH */
+
+/******************************************************************
+ * Functions common for DRBG implementations
+ ******************************************************************/
+
+/*
+ * Seeding or reseeding of the DRBG
+ *
+ * @drbg: DRBG state struct
+ * @pers: personalization / additional information buffer
+ * @reseed: 0 for initial seed process, 1 for reseeding
+ *
+ * return:
+ * 0 on success
+ * error value otherwise
+ */
+static int drbg_seed(struct drbg_state *drbg, struct drbg_string *pers,
+ bool reseed)
+{
+ int ret = 0;
+ unsigned char *entropy = NULL;
+ size_t entropylen = 0;
+ struct drbg_string data1;
+
+ /* 9.1 / 9.2 / 9.3.1 step 3 */
+ if (pers && pers->len > (drbg_max_addtl(drbg))) {
+ pr_devel("DRBG: personalization string too long %lu\n",
+ pers->len);
+ return -EINVAL;
+ }
+
+ if (drbg->test_data && drbg->test_data->testentropy) {
+ drbg_string_fill(&data1, drbg->test_data->testentropy->buf,
+ drbg->test_data->testentropy->len);
+ pr_devel("DRBG: using test entropy\n");
+ } else {
+ /* Gather entropy equal to the security strength of the DRBG.
+ * With a derivation function, a nonce is required in addition
+ * to the entropy. A nonce must be at least 1/2 of the security
+ * strength of the DRBG in size. Thus, entropy * nonce is 3/2
+ * of the strength. The consideration of a nonce is only
+ * applicable during initial seeding. */
+ entropylen = drbg_sec_strength(drbg->core->flags);
+ if (!entropylen)
+ return -EFAULT;
+ if (!reseed)
+ /* make sure we round up strength/2 in
+ * case it is not divisible by 2 */
+ entropylen = ((entropylen + 1) / 2) * 3;
+ pr_devel("DRBG: (re)seeding with %zu bytes of entropy\n",
+ entropylen);
+ entropy = kzalloc(entropylen, GFP_KERNEL);
+ if (!entropy)
+ return -ENOMEM;
+ get_random_bytes(entropy, entropylen);
+ drbg_string_fill(&data1, entropy, entropylen);
+ }
+
+ /* concatenation of entropy with personalization str / addtl input)
+ * the variable pers is directly handed by the caller, check its
+ * contents whether it is appropriate */
+ if (pers && pers->buf && 0 < pers->len && NULL == pers->next) {
+ data1.next = pers;
+ pr_devel("DRBG: using personalization string\n");
+ }
+
+ ret = drbg->d_ops->update(drbg, &data1, reseed);
+ if (ret)
+ goto out;
+
+ drbg->seeded = true;
+ /* 10.1.1.2 / 10.1.1.3 step 5 */
+ drbg->reseed_ctr = 1;
+
+out:
+ if (entropy)
+ kzfree(entropy);
+ return ret;
+}
+
+/*
+ * Free all substructures in a DRBG state without the DRBG state structure
+ */
+static inline void drbg_dealloc_state(struct drbg_state *drbg)
+{
+ if (!drbg)
+ return;
+ if (drbg->V)
+ kzfree(drbg->V);
+ drbg->V = NULL;
+ if (drbg->C)
+ kzfree(drbg->C);
+ drbg->C = NULL;
+ if (drbg->scratchpad)
+ kzfree(drbg->scratchpad);
+ drbg->scratchpad = NULL;
+ drbg->reseed_ctr = 0;
+#ifdef CONFIG_CRYPTO_FIPS
+ if (drbg->prev)
+ kzfree(drbg->prev);
+ drbg->prev = NULL;
+ drbg->fips_primed = false;
+#endif
+}
+
+/*
+ * Allocate all sub-structures for a DRBG state
+ * The DRBG state structure must already be allocated
+ */
+static inline int drbg_alloc_state(struct drbg_state *drbg)
+{
+ int ret = -ENOMEM;
+ unsigned int sb_size = 0;
+
+ if (!drbg)
+ return -EINVAL;
+
+ drbg->V = kzalloc(drbg_statelen(drbg), GFP_KERNEL);
+ if (!drbg->V)
+ goto err;
+ drbg->C = kzalloc(drbg_statelen(drbg), GFP_KERNEL);
+ if (!drbg->C)
+ goto err;
+#ifdef CONFIG_CRYPTO_FIPS
+ drbg->prev = kzalloc(drbg_blocklen(drbg), GFP_KERNEL);
+ if (!drbg->prev)
+ goto err;
+ drbg->fips_primed = false;
+#endif
+ /* scratchpad is only generated for CTR and Hash */
+ if (drbg->core->flags & DRBG_HMAC)
+ sb_size = 0;
+ else if (drbg->core->flags & DRBG_CTR)
+ sb_size = drbg_statelen(drbg) + drbg_blocklen(drbg) + /* temp */
+ drbg_statelen(drbg) + /* df_data */
+ drbg_blocklen(drbg) + /* pad */
+ drbg_blocklen(drbg) + /* iv */
+ drbg_statelen(drbg); /* temp */
+ else
+ sb_size = drbg_statelen(drbg) + drbg_blocklen(drbg);
+
+ if (0 < sb_size) {
+ drbg->scratchpad = kzalloc(sb_size, GFP_KERNEL);
+ if (!drbg->scratchpad)
+ goto err;
+ }
+ spin_lock_init(&drbg->drbg_lock);
+ return 0;
+
+err:
+ drbg_dealloc_state(drbg);
+ return ret;
+}
+
+/*
+ * Strategy to avoid holding long term locks: generate a shadow copy of DRBG
+ * and perform all operations on this shadow copy. After finishing, restore
+ * the updated state of the shadow copy into original drbg state. This way,
+ * only the read and write operations of the original drbg state must be
+ * locked
+ */
+
+/*
+ * Copy the DRBG state
+ */
+static inline void drbg_copy_drbg(struct drbg_state *src,
+ struct drbg_state *dst)
+{
+ if (!src || !dst)
+ return;
+ memcpy(dst->V, src->V, drbg_statelen(src));
+ memcpy(dst->C, src->C, drbg_statelen(src));
+ dst->reseed_ctr = src->reseed_ctr;
+ /* no copy of scratchpad */
+ /* priv_data is initialized with call to crypto_init */
+ /* d_ops and core are set outside, as these parameters are const */
+ dst->seeded = src->seeded;
+ dst->pr = src->pr;
+#ifdef CONFIG_CRYPTO_FIPS
+ dst->fips_primed = src->fips_primed;
+ memcpy(dst->prev, src->prev, drbg_blocklen(src));
+#endif
+ /* test_data is set outside to prevent it being copied back */
+}
+/*
+ * Generate shadow copy of the DRBG state
+ */
+static int drbg_make_shadow(struct drbg_state *drbg, struct drbg_state **shadow)
+{
+ int ret = -ENOMEM;
+ struct drbg_state *tmp = NULL;
+
+ /* some sanity checks */
+ if (!drbg || !drbg->core || !drbg->V || !drbg->C) {
+ pr_devel("DRBG: attempt to generate shadow copy for "
+ "uninitialized DRBG state rejected\n");
+ return -EINVAL;
+ }
+ /* HMAC does not have a scratchpad */
+ if (!(drbg->core->flags & DRBG_HMAC) && NULL == drbg->scratchpad)
+ return -EINVAL;
+
+ tmp = kzalloc(sizeof(struct drbg_state), GFP_KERNEL);
+ if (!tmp)
+ return -ENOMEM;
+
+ /* read-only data as they are defined as const, no lock needed */
+ tmp->core = drbg->core;
+ tmp->d_ops = drbg->d_ops;
+
+ ret = drbg_alloc_state(tmp);
+ if (ret)
+ goto err;
+
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg_copy_drbg(drbg, tmp);
+ /* only make a link to the test buffer, as we only read that data */
+ tmp->test_data = drbg->test_data;
+ spin_unlock_bh(&drbg->drbg_lock);
+ *shadow = tmp;
+ return 0;
+
+err:
+ if (tmp)
+ kzfree(tmp);
+ return ret;
+}
+
+/*
+ * Restore shadow state into original DRBG state
+ */
+static void drbg_restore_shadow(struct drbg_state *drbg,
+ struct drbg_state **shadow)
+{
+ struct drbg_state *tmp = *shadow;
+
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg_copy_drbg(tmp, drbg);
+ spin_unlock_bh(&drbg->drbg_lock);
+ drbg_dealloc_state(tmp);
+ kzfree(tmp);
+ *shadow = NULL;
+}
+
+/*************************************************************************
+ * DRBG interface functions
+ *************************************************************************/
+
+/*
+ * DRBG generate function as required by SP800-90A - this function
+ * generates random numbers
+ *
+ * @drbg DRBG state handle
+ * @buf Buffer where to store the random numbers -- the buffer must already
+ * be pre-allocated by caller
+ * @buflen Length of output buffer - this value defines the number of random
+ * bytes pulled from DRBG
+ * @addtl Additional input that is mixed into state, may be NULL -- note
+ * the entropy is pulled by the DRBG internally unconditionally
+ * as defined in SP800-90A. The additional input is mixed into
+ * the state in addition to the pulled entropy.
+ *
+ * return: generated number of bytes
+ */
+static int drbg_generate(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ int len = 0;
+ struct drbg_state *shadow = NULL;
+
+ if (0 == buflen || !buf) {
+ pr_devel("DRBG: no output buffer provided\n");
+ return -EINVAL;
+ }
+ if (addtl && NULL == addtl->buf && 0 < addtl->len) {
+ pr_devel("DRBG: wrong format of additional information\n");
+ return -EINVAL;
+ }
+
+ len = drbg_make_shadow(drbg, &shadow);
+ if (len) {
+ pr_devel("DRBG: shadow copy cannot be generated\n");
+ return len;
+ }
+ /* 9.3.1 step 2 */
+ len = -EINVAL;
+ if (buflen > (drbg_max_request_bytes(shadow))) {
+ pr_devel("DRBG: requested random numbers too large %u\n",
+ buflen);
+ goto err;
+ }
+ /* 9.3.1 step 3 is implicit with the chosen DRBG */
+ /* 9.3.1 step 4 */
+ if (addtl && addtl->len > (drbg_max_addtl(shadow))) {
+ pr_devel("DRBG: additional information string too long %zu\n",
+ addtl->len);
+ goto err;
+ }
+ /* 9.3.1 step 5 is implicit with the chosen DRBG */
+ /* 9.3.1 step 6 and 9 supplemented by 9.3.2 step c -- the spec is a
+ * bit convoluted here, we make it simpler */
+ if ((drbg_max_requests(shadow)) < shadow->reseed_ctr)
+ shadow->seeded = false;
+
+ /* allocate cipher handle */
+ if (shadow->d_ops->crypto_init) {
+ len = shadow->d_ops->crypto_init(shadow);
+ if (len)
+ goto err;
+ }
+
+ if (shadow->pr || !shadow->seeded) {
+ pr_devel("DRBG: reseeding before generation (prediction "
+ "resistance: %s, state %s)\n",
+ drbg->pr ? "true" : "false",
+ drbg->seeded ? "seeded" : "unseeded");
+ /* 9.3.1 steps 7.1 through 7.3 */
+ len = drbg_seed(shadow, addtl, true);
+ if (len)
+ goto err;
+ /* 9.3.1 step 7.4 */
+ addtl = NULL;
+ }
+ /* 9.3.1 step 8 and 10 */
+ len = shadow->d_ops->generate(shadow, buf, buflen, addtl);
+
+ /* 10.1.1.4 step 6, 10.1.2.5 step 7, 10.2.1.5.2 step 7 */
+ shadow->reseed_ctr++;
+ if (0 >= len)
+ goto err;
+
+ /* 11.3.3 -- re-perform self tests after some generated random
+ * numbers, the chosen value after which self test is performed
+ * is arbitrary, but it should be reasonable */
+ /* Here we do not perform the self tests because of the following
+ * reasons: it is mathematically impossible that the initial self tests
+ * were successfully and the following are not. If the initial would
+ * pass and the following would not, the kernel integrity is violated.
+ * In this case, the entire kernel operation is questionable and it
+ * is unlikely that the integrity violation only affects to the
+ * correct operation of the DRBG.
+ */
+#if 0
+ if (shadow->reseed_ctr && !(shadow->reseed_ctr % 4096)) {
+ int err = 0;
+ pr_devel("DRBG: start to perform self test\n");
+ if (drbg->core->flags & DRBG_HMAC)
+ err = alg_test("drbg(pr(hmac(sha256)))",
+ "drbg(pr(hmac(sha256)))", 0, 0);
+ else if (drbg->core->flags & DRBG_CTR)
+ err = alg_test("drbg(pr(ctr(aes128)))",
+ "drbg(pr(ctr(aes128)))", 0, 0);
+ else
+ err = alg_test("drbg(pr(sha256))",
+ "drbg(pr(sha256))", 0, 0);
+ if (err) {
+ pr_err("DRBG: periodical self test failed\n");
+ /* uninstantiate implies that from now on, only errors
+ * are returned when reusing this DRBG cipher handle */
+ drbg_uninstantiate(drbg);
+ drbg_dealloc_state(shadow);
+ kzfree(shadow);
+ return 0;
+ } else {
+ pr_devel("DRBG: self test successful\n");
+ }
+ }
+#endif
+
+err:
+ if (shadow->d_ops->crypto_fini)
+ shadow->d_ops->crypto_fini(shadow);
+ drbg_restore_shadow(drbg, &shadow);
+ return len;
+}
+
+/*
+ * Wrapper around drbg_generate which can pull arbitrary long strings
+ * from the DRBG without hitting the maximum request limitation.
+ *
+ * Parameters: see drbg_generate
+ * Return codes: see drbg_generate -- if one drbg_generate request fails,
+ * the entire drbg_generate_long request fails
+ */
+static int drbg_generate_long(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ int len = 0;
+ unsigned int slice = 0;
+ do {
+ int tmplen = 0;
+ unsigned int chunk = 0;
+ slice = ((buflen - len) / drbg_max_request_bytes(drbg));
+ chunk = slice ? drbg_max_request_bytes(drbg) : (buflen - len);
+ tmplen = drbg_generate(drbg, buf + len, chunk, addtl);
+ if (0 >= tmplen)
+ return tmplen;
+ len += tmplen;
+ } while (slice > 0);
+ return len;
+}
+
+/*
+ * DRBG instantiation function as required by SP800-90A - this function
+ * sets up the DRBG handle, performs the initial seeding and all sanity
+ * checks required by SP800-90A
+ *
+ * @drbg memory of state -- if NULL, new memory is allocated
+ * @pers Personalization string that is mixed into state, may be NULL -- note
+ * the entropy is pulled by the DRBG internally unconditionally
+ * as defined in SP800-90A. The additional input is mixed into
+ * the state in addition to the pulled entropy.
+ * @coreref reference to core
+ * @pr prediction resistance enabled
+ *
+ * return
+ * 0 on success
+ * error value otherwise
+ */
+static int drbg_instantiate(struct drbg_state *drbg, struct drbg_string *pers,
+ int coreref, bool pr)
+{
+ int ret = -ENOMEM;
+
+ pr_devel("DRBG: Initializing DRBG core %d with prediction resistance "
+ "%s\n", coreref, pr ? "enabled" : "disabled");
+ drbg->core = &cores[coreref];
+ drbg->pr = pr;
+ drbg->seeded = false;
+ switch (drbg->core->flags & DRBG_TYPE_MASK) {
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+ case DRBG_HMAC:
+ drbg->d_ops = &drbg_hmac_ops;
+ break;
+#endif /* CONFIG_CRYPTO_DRBG_HMAC */
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+ case DRBG_HASH:
+ drbg->d_ops = &drbg_hash_ops;
+ break;
+#endif /* CONFIG_CRYPTO_DRBG_HASH */
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+ case DRBG_CTR:
+ drbg->d_ops = &drbg_ctr_ops;
+ break;
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ /* 9.1 step 1 is implicit with the selected DRBG type -- see
+ * drbg_sec_strength() */
+
+ /* 9.1 step 2 is implicit as caller can select prediction resistance
+ * and the flag is copied into drbg->flags --
+ * all DRBG types support prediction resistance */
+
+ /* 9.1 step 4 is implicit in drbg_sec_strength */
+
+ /* no allocation of drbg as this is done by the kernel crypto API */
+ ret = drbg_alloc_state(drbg);
+ if (ret)
+ return ret;
+
+ ret = -EFAULT;
+ /* allocate cipher handle */
+ if (drbg->d_ops->crypto_init && drbg->d_ops->crypto_init(drbg))
+ goto err;
+ /* 9.1 step 6 through 11 */
+ ret = drbg_seed(drbg, pers, false);
+ /* deallocate cipher handle */
+ if (drbg->d_ops->crypto_fini)
+ drbg->d_ops->crypto_fini(drbg);
+ if (ret)
+ goto err;
+
+ return 0;
+
+err:
+ drbg_dealloc_state(drbg);
+ return ret;
+}
+
+/*
+ * DRBG uninstantiate function as required by SP800-90A - this function
+ * frees all buffers and the DRBG handle
+ *
+ * @drbg DRBG state handle
+ *
+ * return
+ * 0 on success
+ */
+static int drbg_uninstantiate(struct drbg_state *drbg)
+{
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg_dealloc_state(drbg);
+ /* no scrubbing of test_data -- this shall survive an uninstantiate */
+ spin_unlock_bh(&drbg->drbg_lock);
+ /* no freeing of drbg as this is done by the kernel crypto API */
+ return 0;
+}
+
+/*
+ * Helper function for setting the test data in the DRBG
+ *
+ * @drbg DRBG state handle
+ * @test_data test data to sets
+ */
+static inline void drbg_set_testdata(struct drbg_state *drbg,
+ struct drbg_test_data *test_data)
+{
+ if (!test_data || !test_data->testentropy)
+ return;
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg->test_data = test_data;
+ spin_unlock_bh(&drbg->drbg_lock);
+}
+
+/***************************************************************
+ * Kernel crypto APi cipher invocations requested by DRBG
+ ***************************************************************/
+
+#if defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_HMAC)
+struct sdesc {
+ struct shash_desc shash;
+ char ctx[];
+};
+
+static int drbg_init_hash_kernel(struct drbg_state *drbg)
+{
+ struct sdesc *sdesc;
+ struct crypto_shash *tfm;
+
+ tfm = crypto_alloc_shash(drbg->core->backend_cra_name, 0, 0);
+ if (IS_ERR(tfm)) {
+ pr_info("DRBG: could not allocate digest TFM handle\n");
+ return PTR_ERR(tfm);
+ }
+ BUG_ON(drbg_blocklen(drbg) != crypto_shash_digestsize(tfm));
+ sdesc = kzalloc(sizeof(struct shash_desc) + crypto_shash_descsize(tfm),
+ GFP_KERNEL);
+ if (!sdesc) {
+ crypto_free_shash(tfm);
+ return -ENOMEM;
+ }
+
+ sdesc->shash.tfm = tfm;
+ sdesc->shash.flags = 0;
+ drbg->priv_data = sdesc;
+ return 0;
+}
+
+static int drbg_fini_hash_kernel(struct drbg_state *drbg)
+{
+ struct sdesc *sdesc = (struct sdesc *)drbg->priv_data;
+ if (sdesc) {
+ crypto_free_shash(sdesc->shash.tfm);
+ kzfree(sdesc);
+ }
+ drbg->priv_data = NULL;
+ return 0;
+}
+
+static int drbg_kcapi_hash(struct drbg_state *drbg, const unsigned char *key,
+ unsigned char *outval, const struct drbg_string *in)
+{
+ struct sdesc *sdesc = (struct sdesc *)drbg->priv_data;
+
+ if (key)
+ crypto_shash_setkey(sdesc->shash.tfm, key, drbg_statelen(drbg));
+ crypto_shash_init(&sdesc->shash);
+ for (; NULL != in; in = in->next)
+ crypto_shash_update(&sdesc->shash, in->buf, in->len);
+ return crypto_shash_final(&sdesc->shash, outval);
+}
+#endif /* (CONFIG_CRYPTO_DRBG_HASH || CONFIG_CRYPTO_DRBG_HMAC) */
+
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+static int drbg_init_sym_kernel(struct drbg_state *drbg)
+{
+ int ret = 0;
+ struct crypto_blkcipher *tfm;
+
+ tfm = crypto_alloc_blkcipher(drbg->core->backend_cra_name, 0, 0);
+ if (IS_ERR(tfm)) {
+ pr_info("DRBG: could not allocate cipher TFM handle\n");
+ return PTR_ERR(tfm);
+ }
+ BUG_ON(drbg_blocklen(drbg) != crypto_blkcipher_blocksize(tfm));
+ drbg->priv_data = tfm;
+ return ret;
+}
+
+static int drbg_fini_sym_kernel(struct drbg_state *drbg)
+{
+ struct crypto_blkcipher *tfm =
+ (struct crypto_blkcipher *)drbg->priv_data;
+ if (tfm)
+ crypto_free_blkcipher(tfm);
+ drbg->priv_data = NULL;
+ return 0;
+}
+
+static int drbg_kcapi_sym(struct drbg_state *drbg, const unsigned char *key,
+ unsigned char *outval, const struct drbg_string *in)
+{
+ int ret = 0;
+ struct scatterlist sg_in, sg_out;
+ struct blkcipher_desc desc;
+ struct crypto_blkcipher *tfm =
+ (struct crypto_blkcipher *)drbg->priv_data;
+
+ desc.tfm = tfm;
+ desc.flags = 0;
+ crypto_blkcipher_setkey(tfm, key, (drbg_keylen(drbg)));
+ /* in is only component */
+ sg_init_one(&sg_in, in->buf, in->len);
+ sg_init_one(&sg_out, outval, drbg_blocklen(drbg));
+ ret = crypto_blkcipher_encrypt(&desc, &sg_out, &sg_in, in->len);
+
+ return ret;
+}
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+
+/***************************************************************
+ * Kernel crypto API interface to register DRBG
+ ***************************************************************/
+
+/*
+ * Look up the DRBG flags by given kernel crypto API cra_name
+ * The code uses the cores definition to do this
+ *
+ * @cra_name kernel crypto API cra_name
+ * @coreref reference to integer which is filled with the pointer to
+ * the applicable core
+ * @pr reference for setting prediction resistance
+ *
+ * return: flags
+ */
+static inline void drbg_convert_tfm_core(const char *cra_name,
+ int *coreref, bool *pr)
+{
+ int i = 0;
+ size_t start = 0;
+ int len = 0;
+
+ *pr = true;
+ /* disassemble the names */
+ if (0 == memcmp(cra_name, "drbg(nopr(", 10)) {
+ start = 10;
+ *pr = false;
+ } else if (0 == memcmp(cra_name, "drbg(pr(", 8)) {
+ start = 8;
+ } else {
+ return;
+ }
+
+ /* remove the first part and the closing parenthesis */
+ len = strlen(cra_name) - start - 2;
+ for (i = 0; ARRAY_SIZE(cores) > i; i++) {
+ if (0 == memcmp(cra_name + start, cores[i].cra_name, len)) {
+ *coreref = i;
+ return;
+ }
+ }
+}
+
+/*
+ * Initialize one DRBG invoked by the kernel crypto API
+ *
+ * Function uses the kernel crypto API cra_name to look up
+ * the flags to instantiate the DRBG
+ */
+static int drbg_kcapi_init(struct crypto_tfm *tfm)
+{
+ struct drbg_state *drbg = crypto_tfm_ctx(tfm);
+ bool pr = false;
+ int coreref = 0;
+
+ drbg_convert_tfm_core(crypto_tfm_alg_name(tfm), &coreref, &pr);
+ /* when personalization string is needed, the caller must call reset
+ * and provide the personalization string as seed information */
+ return drbg_instantiate(drbg, NULL, coreref, pr);
+}
+
+static void drbg_kcapi_cleanup(struct crypto_tfm *tfm)
+{
+ drbg_uninstantiate(crypto_tfm_ctx(tfm));
+}
+
+/*
+ * Generate random numbers invoked by the kernel crypto API:
+ * The API of the kernel crypto API is extended as follows:
+ *
+ * If dlen is larger than zero, rdata is interpreted as the output buffer
+ * where random data is to be stored.
+ *
+ * If dlen is zero, rdata is interpreted as a pointer to a struct drbg_gen
+ * which holds the additional information string that is used for the
+ * DRBG generation process. The output buffer that is to be used to store
+ * data is also pointed to by struct drbg_gen.
+ *
+ */
+static int drbg_kcapi_random(struct crypto_rng *tfm, u8 *rdata,
+ unsigned int dlen)
+{
+ struct drbg_state *drbg = crypto_rng_ctx(tfm);
+ if (0 < dlen) {
+ return drbg_generate_long(drbg, rdata, dlen, NULL);
+ } else {
+ struct drbg_gen *data = (struct drbg_gen *)rdata;
+ /* catch NULL pointer */
+ if (!data)
+ return 0;
+ drbg_set_testdata(drbg, data->test_data);
+ return drbg_generate_long(drbg, data->outbuf, data->outlen,
+ data->addtl);
+ }
+}
+
+/*
+ * Reset the DRBG invoked by the kernel crypto API
+ * The reset implies a full re-initialization of the DRBG. Similar to the
+ * generate function of drbg_kcapi_random, this function extends the
+ * kernel crypto API interface with struct drbg_gen
+ */
+static int drbg_kcapi_reset(struct crypto_rng *tfm, u8 *seed, unsigned int slen)
+{
+ struct drbg_state *drbg = crypto_rng_ctx(tfm);
+ struct crypto_tfm *tfm_base = crypto_rng_tfm(tfm);
+ bool pr = false;
+ struct drbg_string seed_string;
+ int coreref = 0;
+
+ drbg_uninstantiate(drbg);
+ drbg_convert_tfm_core(crypto_tfm_alg_name(tfm_base), &coreref, &pr);
+ if (0 < slen) {
+ drbg_string_fill(&seed_string, seed, slen);
+ return drbg_instantiate(drbg, &seed_string, coreref, pr);
+ } else {
+ struct drbg_gen *data = (struct drbg_gen *)seed;
+ /* allow invocation of API call with NULL, 0 */
+ if (!data)
+ return drbg_instantiate(drbg, NULL, coreref, pr);
+ drbg_set_testdata(drbg, data->test_data);
+ return drbg_instantiate(drbg, data->addtl, coreref, pr);
+ }
+}
+
+/***************************************************************
+ * Kernel module: code to load the module
+ ***************************************************************/
+
+/*
+ * Tests as defined in 11.3.2 in addition to the cipher tests: testing
+ * of the error handling.
+ *
+ * Note, testing of failing seed source as defined in 11.3.2 is not applicable
+ * as seed source of get_random_bytes does not fail.
+ * Note, testing the reseed counter is not done as an automatic reseeding
+ * is performed in drbg_generate when the reseed counter is too large.
+ */
+static inline int __init drbg_healthcheck_sanity(void)
+{
+#ifdef CONFIG_CRYPTO_FIPS
+ unsigned int len = 0;
+#define OUTBUFLEN 16
+ unsigned char buf[OUTBUFLEN];
+ struct drbg_state *drbg = NULL;
+ int ret = -EFAULT;
+ int rc = -EFAULT;
+ bool pr = false;
+ int coreref = 0;
+ struct drbg_string addtl;
+ size_t max_addtllen, max_request_bytes;
+
+ /* only perform test in FIPS mode */
+ if (0 == fips_enabled)
+ return 0;
+
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+ drbg_convert_tfm_core("drbg(nopr(ctr(aes128)))", &coreref, &pr);
+#elif CONFIG_CRYPTO_DRBG_HASH
+ drbg_convert_tfm_core("drbg(nopr(sha256)", &coreref, &pr);
+#else
+ drbg_convert_tfm_core("drbg(nopr(hmac(sha256)))", &coreref, &pr);
+#endif
+
+ drbg = kzalloc(sizeof(struct drbg_state), GFP_KERNEL);
+ if (!drbg)
+ return -ENOMEM;
+
+ /* if the following tests fail, it is likely that there is a buffer
+ * overflow as buf is much smaller than the requested or provided
+ * string lengths -- in case the error handling does not succeed
+ * we may get an OOPS. And we want to get an OOPS as this is a
+ * grave bug */
+
+ /* get a valid instance of DRBG for following tests */
+ ret = drbg_instantiate(drbg, NULL, coreref, pr);
+ if (ret) {
+ rc = ret;
+ goto outbuf;
+ }
+ max_addtllen = drbg_max_addtl(drbg);
+ max_request_bytes = drbg_max_request_bytes(drbg);
+ drbg_string_fill(&addtl, buf, max_addtllen + 1);
+ /* overflow addtllen with additonal info string */
+ len = drbg_generate(drbg, buf, OUTBUFLEN, &addtl);
+ BUG_ON(0 < len);
+ /* overflow max_bits */
+ len = drbg_generate(drbg, buf, (max_request_bytes + 1), NULL);
+ BUG_ON(0 < len);
+ drbg_uninstantiate(drbg);
+
+ /* overflow max addtllen with personalization string */
+ ret = drbg_instantiate(drbg, &addtl, coreref, pr);
+ BUG_ON(0 == ret);
+ /* test uninstantated DRBG */
+ len = drbg_generate(drbg, buf, (max_request_bytes + 1), NULL);
+ BUG_ON(0 < len);
+ /* all tests passed */
+ rc = 0;
+
+ pr_devel("DRBG: Sanity tests for failure code paths successfully "
+ "completed\n");
+
+ drbg_uninstantiate(drbg);
+outbuf:
+ kzfree(drbg);
+ return rc;
+#else /* CONFIG_CRYPTO_FIPS */
+ return 0;
+#endif /* CONFIG_CRYPTO_FIPS */
+}
+
+
+static struct crypto_alg drbg_algs[22];
+
+/*
+ * Fill the array drbg_algs used to register the different DRBGs
+ * with the kernel crypto API. To fill the array, the information
+ * from cores[] is used.
+ */
+static inline void __init drbg_fill_array(unsigned long i, unsigned long j,
+ int pr)
+{
+ int pos = 0;
+
+ memset(&drbg_algs[i], 0, sizeof(struct crypto_alg));
+ if (pr) {
+ memcpy(drbg_algs[i].cra_name, "drbg(pr(", 8);
+ memcpy(drbg_algs[i].cra_driver_name, "drbg_pr_", 8);
+ pos = 8;
+ } else {
+ memcpy(drbg_algs[i].cra_name, "drbg(nopr(", 10);
+ memcpy(drbg_algs[i].cra_driver_name, "drbg_nopr_", 10);
+ pos = 10;
+ }
+ memcpy(drbg_algs[i].cra_name + pos, cores[j].cra_name,
+ strlen(cores[j].cra_name));
+ memcpy(drbg_algs[i].cra_name + pos + strlen(cores[j].cra_name), "))",
+ 2);
+ memcpy(drbg_algs[i].cra_driver_name + pos,
+ cores[j].cra_driver_name, strlen(cores[j].cra_driver_name));
+ drbg_algs[i].cra_priority = 100;
+ drbg_algs[i].cra_flags = CRYPTO_ALG_TYPE_RNG;
+ drbg_algs[i].cra_ctxsize = sizeof(struct drbg_state);
+ drbg_algs[i].cra_type = &crypto_rng_type;
+ drbg_algs[i].cra_module = THIS_MODULE;
+ drbg_algs[i].cra_init = drbg_kcapi_init;
+ drbg_algs[i].cra_exit = drbg_kcapi_cleanup;
+ drbg_algs[i].cra_u.rng.rng_make_random = drbg_kcapi_random;
+ drbg_algs[i].cra_u.rng.rng_reset = drbg_kcapi_reset;
+ drbg_algs[i].cra_u.rng.seedsize = 0;
+}
+
+static int __init drbg_init(void)
+{
+ unsigned int i = 0; /* pointer to drbg_algs */
+ unsigned int j = 0; /* pointer to cores */
+ int ret = -EFAULT;
+
+ ret = drbg_healthcheck_sanity();
+ if (ret)
+ return ret;
+
+ if (ARRAY_SIZE(cores) * 2 > ARRAY_SIZE(drbg_algs))
+ pr_info("DRBG: Not all available DRBGs registered"
+ "(slots needed: %lu, slots available: %lu)\n",
+ ARRAY_SIZE(cores) * 2, ARRAY_SIZE(drbg_algs));
+
+ /* each DRBG definition can be used with PR and without PR, thus
+ * we instantiate each DRBG in cores[] twice */
+ for (j = 0; ARRAY_SIZE(cores) > j; j++) {
+ drbg_fill_array(i, j, 1);
+ i++;
+ drbg_fill_array(i, j, 0);
+ i++;
+ }
+ return crypto_register_algs(drbg_algs, (ARRAY_SIZE(cores) * 2));
+}
+
+void __exit drbg_exit(void)
+{
+ crypto_unregister_algs(drbg_algs, (ARRAY_SIZE(cores) * 2));
+}
+
+module_init(drbg_init);
+module_exit(drbg_exit);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Stephan Mueller <smueller@chronox.de>");
+MODULE_DESCRIPTION("NIST SP800-90A Deterministic Random Bit Generator (DRBG) using following cores:"
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+"HMAC "
+#endif
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+"Hash "
+#endif
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+"CTR"
+#endif
+);
^ permalink raw reply related [flat|nested] 29+ messages in thread* Re: [PATCH v5 1/6] SP800-90A Deterministic Random Bit Generator
2014-04-15 5:35 ` [PATCH v5 " Stephan Mueller
@ 2014-04-15 5:51 ` Joe Perches
2014-04-15 6:08 ` Stephan Mueller
2014-04-26 20:13 ` [PATCH v6 " Stephan Mueller
1 sibling, 1 reply; 29+ messages in thread
From: Joe Perches @ 2014-04-15 5:51 UTC (permalink / raw)
To: Stephan Mueller
Cc: linux-kernel, linux-crypto, aquini, jeremy.wayne.powell, clemens,
pwalten
On Tue, 2014-04-15 at 07:35 +0200, Stephan Mueller wrote:
> diff --git a/crypto/drbg.c b/crypto/drbg.c
[]
> @@ -0,0 +1,1997 @@
[]
> +/***************************************************************
> + * Backend cipher definitions available to DRBG
> + ***************************************************************/
> +
> +const struct drbg_core cores[] = {
cores isn't a very good global name.
I presume this should be static.
^ permalink raw reply [flat|nested] 29+ messages in thread* Re: [PATCH v5 1/6] SP800-90A Deterministic Random Bit Generator
2014-04-15 5:51 ` Joe Perches
@ 2014-04-15 6:08 ` Stephan Mueller
0 siblings, 0 replies; 29+ messages in thread
From: Stephan Mueller @ 2014-04-15 6:08 UTC (permalink / raw)
To: Joe Perches
Cc: linux-kernel, linux-crypto, aquini, jeremy.wayne.powell, clemens,
pwalten
Am Montag, 14. April 2014, 22:51:05 schrieb Joe Perches:
Hi Joe,
> On Tue, 2014-04-15 at 07:35 +0200, Stephan Mueller wrote:
> > diff --git a/crypto/drbg.c b/crypto/drbg.c
>
> []
>
> > @@ -0,0 +1,1997 @@
>
> []
>
> > +/***************************************************************
> > + * Backend cipher definitions available to DRBG
> > + ***************************************************************/
> > +
> > +const struct drbg_core cores[] = {
>
> cores isn't a very good global name.
> I presume this should be static.
Agreed. static added and renamed to drbg_cores. I will wait a few days before
releasing a new version. Maybe other comments show up.
Thanks for the review.
Ciao
Stephan
--
| Cui bono? |
^ permalink raw reply [flat|nested] 29+ messages in thread
* [PATCH v6 1/6] SP800-90A Deterministic Random Bit Generator
2014-04-15 5:35 ` [PATCH v5 " Stephan Mueller
2014-04-15 5:51 ` Joe Perches
@ 2014-04-26 20:13 ` Stephan Mueller
2014-05-20 21:32 ` Rafael Aquini
1 sibling, 1 reply; 29+ messages in thread
From: Stephan Mueller @ 2014-04-26 20:13 UTC (permalink / raw)
To: linux-kernel, linux-crypto
Cc: aquini, jeremy.wayne.powell, clemens, pwalten, joe
Changes v6:
* change name of array cores to drbg_cores as suggested by Joe Perches
* make drbg_cores static as suggested by Joe Perches
* catch possible programming error regarding array overflow in drbg_algs gracefully
Signed-off-by: Stephan Mueller <smueller@chronox.de>
---
create mode 100644 crypto/drbg.c
diff --git a/crypto/drbg.c b/crypto/drbg.c
new file mode 100644
index 0000000..cee4e1a
--- /dev/null
+++ b/crypto/drbg.c
@@ -0,0 +1,2001 @@
+/*
+ * DRBG: Deterministic Random Bits Generator
+ * Based on NIST Recommended DRBG from NIST SP800-90A with the following
+ * properties:
+ * * CTR DRBG with DF with AES-128, AES-192, AES-256 cores
+ * * Hash DRBG with DF with SHA-1, SHA-256, SHA-384, SHA-512 cores
+ * * HMAC DRBG with DF with SHA-1, SHA-256, SHA-384, SHA-512 cores
+ * * with and without prediction resistance
+ *
+ * Copyright Stephan Mueller <smueller@chronox.de>, 2014
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, and the entire permission notice in its entirety,
+ * including the disclaimer of warranties.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote
+ * products derived from this software without specific prior
+ * written permission.
+ *
+ * ALTERNATIVELY, this product may be distributed under the terms of
+ * the GNU General Public License, in which case the provisions of the GPL are
+ * required INSTEAD OF the above restrictions. (This clause is
+ * necessary due to a potential bad interaction between the GPL and
+ * the restrictions contained in a BSD-style copyright.)
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF
+ * WHICH ARE HEREBY DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+ * USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * DRBG Usage
+ * ==========
+ * The SP 800-90A DRBG allows the user to specify a personalization string
+ * for initialization as well as an additional information string for each
+ * random number request. The following code fragments show how a caller
+ * uses the kernel crypto API to use the full functionality of the DRBG.
+ *
+ * Usage without any additional data
+ * ---------------------------------
+ * struct crypto_rng *drng;
+ * int err;
+ * char data[DATALEN];
+ *
+ * drng = crypto_alloc_rng(drng_name, 0, 0);
+ * err = crypto_rng_get_bytes(drng, &data, DATALEN);
+ * crypto_free_rng(drng);
+ *
+ *
+ * Usage with personalization string during initialization
+ * -------------------------------------------------------
+ * struct crypto_rng *drng;
+ * int err;
+ * char data[DATALEN];
+ * struct drbg_string pers;
+ * char personalization[11] = "some-string";
+ *
+ * drbg_string_fill(&pers, personalization, strlen(personalization));
+ * drng = crypto_alloc_rng(drng_name, 0, 0);
+ * // The reset completely re-initializes the DRBG with the provided
+ * // personalization string
+ * err = crypto_rng_reset(drng, &personalization, strlen(personalization));
+ * err = crypto_rng_get_bytes(drng, &data, DATALEN);
+ * crypto_free_rng(drng);
+ *
+ *
+ * Usage with additional information string during random number request
+ * ---------------------------------------------------------------------
+ * struct crypto_rng *drng;
+ * int err;
+ * char data[DATALEN];
+ * char addtl_string[11] = "some-string";
+ * string drbg_string addtl;
+ *
+ * drbg_string_fill(&addtl, addtl_string, strlen(addtl_string));
+ * drng = crypto_alloc_rng(drng_name, 0, 0);
+ * // The following call is a wrapper to crypto_rng_get_bytes() and returns
+ * // the same error codes.
+ * err = crypto_drbg_get_bytes_addtl(drng, &data, DATALEN, &addtl);
+ * crypto_free_rng(drng);
+ *
+ *
+ * Usage with personalization and additional information strings
+ * -------------------------------------------------------------
+ * Just mix both scenarios above.
+ */
+
+#include <crypto/drbg.h>
+
+#if !defined(CONFIG_CRYPTO_DRBG_HASH) && \
+ !defined(CONFIG_CRYPTO_DRBG_HMAC) && \
+ !defined(CONFIG_CRYPTO_DRBG_CTR)
+#warning "The DRBG code is useless without compiling at least one DRBG type"
+#endif
+
+/***************************************************************
+ * Backend cipher definitions available to DRBG
+ ***************************************************************/
+
+static const struct drbg_core drbg_cores[] = {
+ /* Hash DRBGs */
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+ {
+ .flags = DRBG_HASH | DRBG_STRENGTH128,
+ .statelen = 55, /* 440 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 20,
+ .cra_name = "sha1",
+ .cra_driver_name = "sha1",
+ .backend_cra_name = "sha1",
+ }, {
+ .flags = DRBG_HASH | DRBG_STRENGTH256,
+ .statelen = 55, /* 440 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 32,
+ .cra_name = "sha256",
+ .cra_driver_name = "sha256",
+ .backend_cra_name = "sha256",
+ }, {
+ .flags = DRBG_HASH | DRBG_STRENGTH256,
+ .statelen = 111, /* 888 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 48,
+ .cra_name = "sha384",
+ .cra_driver_name = "sha384",
+ .backend_cra_name = "sha384",
+ }, {
+ .flags = DRBG_HASH | DRBG_STRENGTH256,
+ .statelen = 111, /* 888 bits */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 64,
+ .cra_name = "sha512",
+ .cra_driver_name = "sha512",
+ .backend_cra_name = "sha512",
+ },
+#endif /* CONFIG_CRYPTO_DRBG_HASH */
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+ {
+ /* HMAC DRBGs */
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 20, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 20,
+ .cra_name = "hmac(sha1)",
+ .cra_driver_name = "hmac_sha1",
+ .backend_cra_name = "hmac(sha1)",
+ }, {
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 32, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 32,
+ .cra_name = "hmac(sha256)",
+ .cra_driver_name = "hmac_sha256",
+ .backend_cra_name = "hmac(sha256)",
+ }, {
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 48, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 48,
+ .cra_name = "hmac(sha384)",
+ .cra_driver_name = "hmac_sha384",
+ .backend_cra_name = "hmac(sha384)",
+ }, {
+ .flags = DRBG_HMAC | DRBG_STRENGTH256,
+ .statelen = 64, /* block length of cipher */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 64,
+ .cra_name = "hmac(sha512)",
+ .cra_driver_name = "hmac_sha512",
+ .backend_cra_name = "hmac(sha512)",
+ },
+#endif /* CONFIG_CRYPTO_DRBG_HMAC */
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+ {
+ /* block ciphers */
+ .flags = DRBG_CTR | DRBG_STRENGTH128,
+ .statelen = 32, /* 256 bits as defined in 10.2.1 */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 16,
+ .cra_name = "ctr(aes128)",
+ .cra_driver_name = "ctr_aes128",
+ .backend_cra_name = "ecb(aes)",
+ }, {
+ /* block ciphers */
+ .flags = DRBG_CTR | DRBG_STRENGTH192,
+ .statelen = 40, /* 320 bits as defined in 10.2.1 */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 16,
+ .cra_name = "ctr(aes192)",
+ .cra_driver_name = "ctr_aes192",
+ .backend_cra_name = "ecb(aes)",
+ }, {
+ /* block ciphers */
+ .flags = DRBG_CTR | DRBG_STRENGTH256,
+ .statelen = 48, /* 384 bits as defined in 10.2.1 */
+ .max_addtllen = 35,
+ .max_bits = 19,
+ .max_req = 48,
+ .blocklen_bytes = 16,
+ .cra_name = "ctr(aes256)",
+ .cra_driver_name = "ctr_aes256",
+ .backend_cra_name = "ecb(aes)",
+ },
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+};
+
+/******************************************************************
+ * Generic helper functions
+ ******************************************************************/
+
+/*
+ * Return strength of DRBG according to SP800-90A section 8.4
+ *
+ * @flags DRBG flags reference
+ *
+ * Return: normalized strength in *bytes* value or 32 as default
+ * to counter programming errors
+ */
+static inline unsigned short drbg_sec_strength(drbg_flag_t flags)
+{
+ switch (flags & DRBG_STRENGTH_MASK) {
+ case DRBG_STRENGTH128:
+ return 16;
+ case DRBG_STRENGTH192:
+ return 24;
+ case DRBG_STRENGTH256:
+ return 32;
+ default:
+ return 32;
+ }
+}
+
+/*
+ * FIPS 140-2 continuous self test
+ * The test is performed on the result of one round of the output
+ * function. Thus, the function implicitly knows the size of the
+ * buffer.
+ *
+ * The FIPS test can be called in an endless loop until it returns
+ * true. Although the code looks like a potential for a deadlock, it
+ * is not the case, because returning a false cannot mathematically
+ * occur (except once when a reseed took place and the updated state
+ * would is now set up such that the generation of new value returns
+ * an identical one -- this is most unlikely and would happen only once).
+ * Thus, if this function repeatedly returns false and thus would cause
+ * a deadlock, the integrity of the entire kernel is lost.
+ *
+ * @drbg DRBG handle
+ * @buf output buffer of random data to be checked
+ *
+ * return:
+ * true on success
+ * false on error
+ */
+static bool drbg_fips_continuous_test(struct drbg_state *drbg,
+ const unsigned char *buf)
+{
+#ifdef CONFIG_CRYPTO_FIPS
+ int ret = 0;
+ /* skip test if we test the overall system */
+ if (drbg->test_data)
+ return true;
+ /* only perform test in FIPS mode */
+ if (0 == fips_enabled)
+ return true;
+ if (!drbg->fips_primed) {
+ /* Priming of FIPS test */
+ memcpy(drbg->prev, buf, drbg_blocklen(drbg));
+ drbg->fips_primed = true;
+ /* return false due to priming, i.e. another round is needed */
+ return false;
+ }
+ ret = memcmp(drbg->prev, buf, drbg_blocklen(drbg));
+ memcpy(drbg->prev, buf, drbg_blocklen(drbg));
+ /* the test shall pass when the two compared values are not equal */
+ return ret != 0;
+#else
+ return true;
+#endif /* CONFIG_CRYPTO_FIPS */
+}
+
+/*
+ * Convert an integer into a byte representation of this integer.
+ * The byte representation is big-endian
+ *
+ * @buf buffer holding the converted integer
+ * @val value to be converted
+ * @buflen length of buffer
+ */
+#if (defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_CTR))
+static inline void drbg_int2byte(unsigned char *buf, uint64_t val,
+ size_t buflen)
+{
+ unsigned char *byte;
+ uint64_t i;
+
+ byte = buf + (buflen - 1);
+ for (i = 0; i < buflen; i++)
+ *(byte--) = val >> (i * 8) & 0xff;
+}
+
+/*
+ * Increment buffer
+ *
+ * @dst buffer to increment
+ * @add value to add
+ */
+static inline void drbg_add_buf(unsigned char *dst, size_t dstlen,
+ const unsigned char *add, size_t addlen)
+{
+ /* implied: dstlen > addlen */
+ unsigned char *dstptr;
+ const unsigned char *addptr;
+ unsigned int remainder = 0;
+ size_t len = addlen;
+
+ dstptr = dst + (dstlen-1);
+ addptr = add + (addlen-1);
+ while (len) {
+ remainder += *dstptr + *addptr;
+ *dstptr = remainder & 0xff;
+ remainder >>= 8;
+ len--; dstptr--; addptr--;
+ }
+ len = dstlen - addlen;
+ while (len && remainder > 0) {
+ remainder = *dstptr + 1;
+ *dstptr = remainder & 0xff;
+ remainder >>= 8;
+ len--; dstptr--;
+ }
+}
+#endif /* defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_CTR) */
+
+/******************************************************************
+ * CTR DRBG callback functions
+ ******************************************************************/
+
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+static int drbg_kcapi_sym(struct drbg_state *drbg, const unsigned char *key,
+ unsigned char *outval, const struct drbg_string *in);
+static int drbg_init_sym_kernel(struct drbg_state *drbg);
+static int drbg_fini_sym_kernel(struct drbg_state *drbg);
+
+/* BCC function for CTR DRBG as defined in 10.4.3 */
+static int drbg_ctr_bcc(struct drbg_state *drbg,
+ unsigned char *out, const unsigned char *key,
+ struct drbg_string *in)
+{
+ int ret = -EFAULT;
+ struct drbg_string *curr = in;
+ size_t inpos = curr->len;
+ const unsigned char *pos = curr->buf;
+ struct drbg_string data;
+
+ drbg_string_fill(&data, out, drbg_blocklen(drbg));
+
+ /* 10.4.3 step 1 */
+ memset(out, 0, drbg_blocklen(drbg));
+
+ /* 10.4.3 step 2 / 4 */
+ while (inpos) {
+ short cnt = 0;
+ /* 10.4.3 step 4.1 */
+ for (cnt = 0; cnt < drbg_blocklen(drbg); cnt++) {
+ out[cnt] ^= *pos;
+ pos++; inpos--;
+ /* the following branch implements the linked list
+ * iteration. If we are at the end of the current data
+ * set, we have to start using the next data set if
+ * available -- the inpos value always points to the
+ * current byte and will be zero if we have processed
+ * the last byte of the last linked list member */
+ if (0 == inpos) {
+ curr = curr->next;
+ if (NULL != curr) {
+ pos = curr->buf;
+ inpos = curr->len;
+ } else {
+ inpos = 0;
+ break;
+ }
+ }
+ }
+ /* 10.4.3 step 4.2 */
+ ret = drbg_kcapi_sym(drbg, key, out, &data);
+ if (ret)
+ return ret;
+ /* 10.4.3 step 2 */
+ }
+ return 0;
+}
+
+/*
+ * scratchpad usage: drbg_ctr_update is interlinked with drbg_ctr_df
+ * (and drbg_ctr_bcc, but this function does not need any temporary buffers),
+ * the scratchpad is used as follows:
+ * drbg_ctr_update:
+ * temp
+ * start: drbg->scratchpad
+ * length: drbg_statelen(drbg) + drbg_blocklen(drbg)
+ * note: the cipher writing into this variable works
+ * blocklen-wise. Now, when the statelen is not a multiple
+ * of blocklen, the generateion loop below "spills over"
+ * by at most blocklen. Thus, we need to give sufficient
+ * memory.
+ * df_data
+ * start: drbg->scratchpad +
+ * drbg_statelen(drbg) + drbg_blocklen(drbg)
+ * length: drbg_statelen(drbg)
+ *
+ * drbg_ctr_df:
+ * pad
+ * start: df_data + drbg_statelen(drbg)
+ * length: drbg_blocklen(drbg)
+ * iv
+ * start: pad + drbg_blocklen(drbg)
+ * length: drbg_blocklen(drbg)
+ * temp
+ * start: iv + drbg_blocklen(drbg)
+ * length: (drbg_keylen(drbg) + drbg_blocklen(drbg) ==
+ * drbg_statelen(drbg))
+ */
+
+/* Derivation Function for CTR DRBG as defined in 10.4.2 */
+static int drbg_ctr_df(struct drbg_state *drbg,
+ unsigned char *df_data, size_t bytes_to_return,
+ struct drbg_string *addtl)
+{
+ int ret = -EFAULT;
+ unsigned char L_N[8];
+ /* S3 is input */
+ struct drbg_string S1, S2, S4, cipherin;
+ struct drbg_string *tempstr = addtl;
+ unsigned char *pad = df_data + drbg_statelen(drbg);
+ unsigned char *iv = pad + drbg_blocklen(drbg);
+ unsigned char *temp = iv + drbg_blocklen(drbg);
+ size_t padlen = 0;
+ unsigned int templen = 0;
+ /* 10.4.2 step 7 */
+ unsigned int i = 0;
+ /* 10.4.2 step 8 */
+ const unsigned char *K = (unsigned char *)
+ "\x00\x01\x02\x03\x04\x05\x06\x07"
+ "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f"
+ "\x10\x11\x12\x13\x14\x15\x16\x17"
+ "\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f";
+ unsigned char *X;
+ size_t generated_len = 0;
+ size_t inputlen = 0;
+
+ memset(pad, 0, drbg_blocklen(drbg));
+ memset(iv, 0, drbg_blocklen(drbg));
+ memset(temp, 0, drbg_statelen(drbg));
+
+ /* 10.4.2 step 1 is implicit as we work byte-wise */
+
+ /* 10.4.2 step 2 */
+ if ((512/8) < bytes_to_return)
+ return -EINVAL;
+
+ /* 10.4.2 step 2 -- calculate the entire length of all input data */
+ for (; NULL != tempstr; tempstr = tempstr->next)
+ inputlen += tempstr->len;
+ drbg_int2byte(&L_N[0], inputlen, 4);
+
+ /* 10.4.2 step 3 */
+ drbg_int2byte(&L_N[4], bytes_to_return, 4);
+
+ /* 10.4.2 step 5: length is L_N, input_string, one byte, padding */
+ padlen = (inputlen + sizeof(L_N) + 1) % (drbg_blocklen(drbg));
+ /* wrap the padlen appropriately */
+ if (padlen)
+ padlen = drbg_blocklen(drbg) - padlen;
+ /* pad / padlen contains the 0x80 byte and the following zero bytes, so
+ * add one for byte for 0x80 */
+ padlen++;
+ pad[0] = 0x80;
+
+ /* 10.4.2 step 4 -- first fill the linked list and then order it */
+ drbg_string_fill(&S1, iv, drbg_blocklen(drbg));
+ drbg_string_fill(&S2, L_N, sizeof(L_N));
+ drbg_string_fill(&S4, pad, padlen);
+ S1.next = &S2;
+ S2.next = addtl;
+ /* splice in addtl between S2 and S4 -- we place S4 at the end of the
+ * input data chain */
+ tempstr = addtl;
+ for (; NULL != tempstr; tempstr = tempstr->next)
+ if (NULL == tempstr->next)
+ break;
+ tempstr->next = &S4;
+
+ /* 10.4.2 step 9 */
+ while (templen < (drbg_keylen(drbg) + (drbg_blocklen(drbg)))) {
+ /* 10.4.2 step 9.1 - the padding is implicit as the buffer
+ * holds zeros after allocation -- even the increment of i
+ * is irrelevant as the increment remains within length of i */
+ drbg_int2byte(iv, i, 4);
+ /* 10.4.2 step 9.2 -- BCC and concatenation with temp */
+ ret = drbg_ctr_bcc(drbg, temp + templen, K, &S1);
+ if (ret)
+ goto out;
+ /* 10.4.2 step 9.3 */
+ i++;
+ templen += drbg_blocklen(drbg);
+ }
+
+ /* 10.4.2 step 11 */
+ /* implicit key len with seedlen - blocklen according to table 3 */
+ X = temp + (drbg_keylen(drbg));
+ drbg_string_fill(&cipherin, X, drbg_blocklen(drbg));
+
+ /* 10.4.2 step 12: overwriting of outval */
+
+ /* 10.4.2 step 13 */
+ while (generated_len < bytes_to_return) {
+ short blocklen = 0;
+ /* 10.4.2 step 13.1 */
+ /* the truncation of the key length is implicit as the key
+ * is only drbg_blocklen in size -- check for the implementation
+ * of the cipher function callback */
+ ret = drbg_kcapi_sym(drbg, temp, X, &cipherin);
+ if (ret)
+ goto out;
+ blocklen = (drbg_blocklen(drbg) <
+ (bytes_to_return - generated_len)) ?
+ drbg_blocklen(drbg) :
+ (bytes_to_return - generated_len);
+ /* 10.4.2 step 13.2 and 14 */
+ memcpy(df_data + generated_len, X, blocklen);
+ generated_len += blocklen;
+ }
+
+ ret = 0;
+
+out:
+ memset(iv, 0, drbg_blocklen(drbg));
+ memset(temp, 0, drbg_statelen(drbg));
+ memset(pad, 0, drbg_blocklen(drbg));
+ return ret;
+}
+
+/* update function of CTR DRBG as defined in 10.2.1.2 */
+static int drbg_ctr_update(struct drbg_state *drbg,
+ struct drbg_string *addtl, int reseed)
+{
+ int ret = -EFAULT;
+ /* 10.2.1.2 step 1 */
+ unsigned char *temp = drbg->scratchpad;
+ unsigned char *df_data = drbg->scratchpad + drbg_statelen(drbg) +
+ drbg_blocklen(drbg);
+ unsigned char *temp_p, *df_data_p; /* pointer to iterate over buffers */
+ unsigned int len = 0;
+ struct drbg_string cipherin;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ memset(temp, 0, drbg_statelen(drbg) + drbg_blocklen(drbg));
+ memset(df_data, 0, drbg_statelen(drbg));
+
+ /* 10.2.1.3.2 step 2 and 10.2.1.4.2 step 2 */
+ if (addtl && 0 < addtl->len) {
+ ret = drbg_ctr_df(drbg, df_data, drbg_statelen(drbg),
+ addtl);
+ if (ret)
+ goto out;
+ }
+
+ drbg_string_fill(&cipherin, drbg->V, drbg_blocklen(drbg));
+ /* 10.2.1.3.2 step 2 and 3 -- are already covered as we memset(0)
+ * all memory during initialization */
+ while (len < (drbg_statelen(drbg))) {
+ /* 10.2.1.2 step 2.1 */
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ /* 10.2.1.2 step 2.2 */
+ /* using target of temp + len: 10.2.1.2 step 2.3 and 3 */
+ ret = drbg_kcapi_sym(drbg, drbg->C, temp + len, &cipherin);
+ if (ret)
+ goto out;
+ /* 10.2.1.2 step 2.3 and 3 */
+ len += drbg_blocklen(drbg);
+ }
+
+ /* 10.2.1.2 step 4 */
+ temp_p = temp;
+ df_data_p = df_data;
+ for (len = 0; len < drbg_statelen(drbg); len++) {
+ *temp_p ^= *df_data_p;
+ df_data_p++; temp_p++;
+ }
+
+ /* 10.2.1.2 step 5 */
+ memcpy(drbg->C, temp, drbg_keylen(drbg));
+ /* 10.2.1.2 step 6 */
+ memcpy(drbg->V, temp + drbg_keylen(drbg), drbg_blocklen(drbg));
+ ret = 0;
+
+out:
+ memset(temp, 0, drbg_statelen(drbg) + drbg_blocklen(drbg));
+ memset(df_data, 0, drbg_statelen(drbg));
+ return ret;
+}
+
+/*
+ * scratchpad use: drbg_ctr_update is called independently from
+ * drbg_ctr_extract_bytes. Therefore, the scratchpad is reused
+ */
+/* Generate function of CTR DRBG as defined in 10.2.1.5.2 */
+static int drbg_ctr_generate(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ int len = 0;
+ int ret = 0;
+ struct drbg_string data;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+
+ /* 10.2.1.5.2 step 2 */
+ if (addtl && 0 < addtl->len) {
+ addtl->next = NULL;
+ ret = drbg_ctr_update(drbg, addtl, 1);
+ if (ret)
+ return 0;
+ }
+
+ /* 10.2.1.5.2 step 4.1 */
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ drbg_string_fill(&data, drbg->V, drbg_blocklen(drbg));
+ while (len < buflen) {
+ int outlen = 0;
+ /* 10.2.1.5.2 step 4.2 */
+ ret = drbg_kcapi_sym(drbg, drbg->C, drbg->scratchpad, &data);
+ if (ret) {
+ len = ret;
+ goto out;
+ }
+ outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
+ drbg_blocklen(drbg) : (buflen - len);
+ if (!drbg_fips_continuous_test(drbg, drbg->scratchpad)) {
+ /* 10.2.1.5.2 step 6 */
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ continue;
+ }
+ /* 10.2.1.5.2 step 4.3 */
+ memcpy(buf + len, drbg->scratchpad, outlen);
+ len += outlen;
+ /* 10.2.1.5.2 step 6 */
+ if (len < buflen)
+ drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
+ }
+
+ /* 10.2.1.5.2 step 6 */
+ /*TODO the DF function is called again since according to step
+ * 2, the "additional_input" after step 2 is the output of the DF
+ * function -- when we save the DF output as a replacement
+ * for the addtl_input data, we do not need to call the DF again here */
+ if (addtl)
+ addtl->next = NULL;
+ ret = drbg_ctr_update(drbg, addtl, 1);
+ if (ret)
+ len = ret;
+
+out:
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ return len;
+}
+
+static struct drbg_state_ops drbg_ctr_ops = {
+ .update = drbg_ctr_update,
+ .generate = drbg_ctr_generate,
+ .crypto_init = drbg_init_sym_kernel,
+ .crypto_fini = drbg_fini_sym_kernel,
+};
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+
+/******************************************************************
+ * HMAC DRBG callback functions
+ ******************************************************************/
+
+#if defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_HMAC)
+static int drbg_kcapi_hash(struct drbg_state *drbg, const unsigned char *key,
+ unsigned char *outval, const struct drbg_string *in);
+static int drbg_init_hash_kernel(struct drbg_state *drbg);
+static int drbg_fini_hash_kernel(struct drbg_state *drbg);
+#endif /* (CONFIG_CRYPTO_DRBG_HASH || CONFIG_CRYPTO_DRBG_HMAC) */
+
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+/* update function of HMAC DRBG as defined in 10.1.2.2 */
+static int drbg_hmac_update(struct drbg_state *drbg,
+ struct drbg_string *seed, int reseed)
+{
+ int ret = -EFAULT;
+ int i = 0;
+ struct drbg_string seed1, seed2, cipherin;
+
+ if (!reseed) {
+ /* 10.1.2.3 step 2 already implicitly covered with
+ * the initial memset(0) of drbg->C */
+ memset(drbg->C, 0, drbg_statelen(drbg));
+ memset(drbg->V, 1, drbg_statelen(drbg));
+ }
+
+ /* build linked list which implements the concatenation and fill
+ * first part*/
+ drbg_string_fill(&seed1, drbg->V, drbg_statelen(drbg));
+ /* buffer will be filled in for loop below with one byte */
+ drbg_string_fill(&seed2, NULL, 1);
+ seed1.next = &seed2;
+ /* seed may be NULL */
+ seed2.next = seed;
+
+ drbg_string_fill(&cipherin, drbg->V, drbg_statelen(drbg));
+ /* we execute two rounds of V/K massaging */
+ for (i = 2; 0 < i; i--) {
+ /* first round uses 0x0, second 0x1 */
+ unsigned char prefix = DRBG_PREFIX0;
+ if (1 == i)
+ prefix = DRBG_PREFIX1;
+ /* 10.1.2.2 step 1 and 4 -- concatenation and HMAC for key */
+ seed2.buf = &prefix;
+ ret = drbg_kcapi_hash(drbg, drbg->C, drbg->C, &seed1);
+ if (ret)
+ return ret;
+
+ /* 10.1.2.2 step 2 and 5 -- HMAC for V */
+ ret = drbg_kcapi_hash(drbg, drbg->C, drbg->V, &cipherin);
+ if (ret)
+ return ret;
+
+ /* 10.1.2.2 step 3 */
+ if (!seed || 0 == seed->len)
+ return ret;
+ }
+
+ return 0;
+}
+
+/* generate function of HMAC DRBG as defined in 10.1.2.5 */
+static int drbg_hmac_generate(struct drbg_state *drbg,
+ unsigned char *buf,
+ unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ int len = 0;
+ int ret = 0;
+ struct drbg_string data;
+
+ /* 10.1.2.5 step 2 */
+ if (addtl && 0 < addtl->len) {
+ addtl->next = NULL;
+ ret = drbg_hmac_update(drbg, addtl, 1);
+ if (ret)
+ return ret;
+ }
+
+ drbg_string_fill(&data, drbg->V, drbg_statelen(drbg));
+ while (len < buflen) {
+ unsigned int outlen = 0;
+ /* 10.1.2.5 step 4.1 */
+ ret = drbg_kcapi_hash(drbg, drbg->C, drbg->V, &data);
+ if (ret)
+ return ret;
+ outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
+ drbg_blocklen(drbg) : (buflen - len);
+ if (!drbg_fips_continuous_test(drbg, drbg->V))
+ continue;
+
+ /* 10.1.2.5 step 4.2 */
+ memcpy(buf + len, drbg->V, outlen);
+ len += outlen;
+ }
+
+ /* 10.1.2.5 step 6 */
+ if (addtl)
+ addtl->next = NULL;
+ ret = drbg_hmac_update(drbg, addtl, 1);
+ if (ret)
+ return ret;
+
+ return len;
+}
+
+static struct drbg_state_ops drbg_hmac_ops = {
+ .update = drbg_hmac_update,
+ .generate = drbg_hmac_generate,
+ .crypto_init = drbg_init_hash_kernel,
+ .crypto_fini = drbg_fini_hash_kernel,
+
+};
+#endif /* CONFIG_CRYPTO_DRBG_HMAC */
+
+/******************************************************************
+ * Hash DRBG callback functions
+ ******************************************************************/
+
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+/*
+ * scratchpad usage: as drbg_hash_update and drbg_hash_df are used
+ * interlinked, the scratchpad is used as follows:
+ * drbg_hash_update
+ * start: drbg->scratchpad
+ * length: drbg_statelen(drbg)
+ * drbg_hash_df:
+ * start: drbg->scratchpad + drbg_statelen(drbg)
+ * length: drbg_blocklen(drbg)
+ */
+/* Derivation Function for Hash DRBG as defined in 10.4.1 */
+static int drbg_hash_df(struct drbg_state *drbg,
+ unsigned char *outval, size_t outlen,
+ struct drbg_string *entropy)
+{
+ int ret = 0;
+ size_t len = 0;
+ unsigned char input[5];
+ unsigned char *tmp = drbg->scratchpad + drbg_statelen(drbg);
+ struct drbg_string data1;
+
+ memset(tmp, 0, drbg_blocklen(drbg));
+
+ /* 10.4.1 step 3 */
+ input[0] = 1;
+ drbg_int2byte(&input[1], (outlen * 8), 4);
+
+ /* 10.4.1 step 4.1 -- concatenation of data for input into hash */
+ drbg_string_fill(&data1, input, 5);
+ data1.next = entropy;
+
+ /* 10.4.1 step 4 */
+ while (len < outlen) {
+ short blocklen = 0;
+ /* 10.4.1 step 4.1 */
+ ret = drbg_kcapi_hash(drbg, NULL, tmp, &data1);
+ if (ret)
+ goto out;
+ /* 10.4.1 step 4.2 */
+ input[0]++;
+ blocklen = (drbg_blocklen(drbg) < (outlen - len)) ?
+ drbg_blocklen(drbg) : (outlen - len);
+ memcpy(outval + len, tmp, blocklen);
+ len += blocklen;
+ }
+
+out:
+ memset(tmp, 0, drbg_blocklen(drbg));
+ return ret;
+}
+
+/* update function for Hash DRBG as defined in 10.1.1.2 / 10.1.1.3 */
+static int drbg_hash_update(struct drbg_state *drbg, struct drbg_string *seed,
+ int reseed)
+{
+ int ret = 0;
+ struct drbg_string data1, data2;
+ unsigned char *V = drbg->scratchpad;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ memset(drbg->scratchpad, 0, drbg_statelen(drbg));
+ if (!seed)
+ return -EINVAL;
+
+ if (reseed) {
+ /* 10.1.1.3 step 1: string length is concatenation of
+ * 1 byte, V and seed (which is concatenated entropy/addtl
+ * input)
+ */
+ memcpy(V, drbg->V, drbg_statelen(drbg));
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, V, drbg_statelen(drbg));
+ data1.next = &data2;
+ data2.next = seed;
+ } else {
+ drbg_string_fill(&data1, seed->buf, seed->len);
+ data1.next = seed->next;
+ }
+
+ /* 10.1.1.2 / 10.1.1.3 step 2 and 3 */
+ ret = drbg_hash_df(drbg, drbg->V, drbg_statelen(drbg), &data1);
+ if (ret)
+ goto out;
+
+ /* 10.1.1.2 / 10.1.1.3 step 4 -- concatenation */
+ prefix = DRBG_PREFIX0;
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, drbg->V, drbg_statelen(drbg));
+ data1.next = &data2;
+ /* 10.1.1.2 / 10.1.1.3 step 4 -- df operation */
+ ret = drbg_hash_df(drbg, drbg->C, drbg_statelen(drbg), &data1);
+
+out:
+ memset(drbg->scratchpad, 0, drbg_statelen(drbg));
+ return ret;
+}
+
+/* processing of additional information string for Hash DRBG */
+static int drbg_hash_process_addtl(struct drbg_state *drbg,
+ struct drbg_string *addtl)
+{
+ int ret = 0;
+ struct drbg_string data1, data2;
+ struct drbg_string *data3;
+ unsigned char prefix = DRBG_PREFIX2;
+
+ /* this is value w as per documentation */
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+
+ /* 10.1.1.4 step 2 */
+ if (!addtl || 0 == addtl->len)
+ return 0;
+
+ /* 10.1.1.4 step 2a -- concatenation */
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, drbg->V, drbg_statelen(drbg));
+ data3 = addtl;
+ data1.next = &data2;
+ data2.next = data3;
+ data3->next = NULL;
+ /* 10.1.1.4 step 2a -- cipher invocation */
+ ret = drbg_kcapi_hash(drbg, NULL, drbg->scratchpad, &data1);
+ if (ret)
+ goto out;
+
+ /* 10.1.1.4 step 2b */
+ drbg_add_buf(drbg->V, drbg_statelen(drbg),
+ drbg->scratchpad, drbg_blocklen(drbg));
+
+out:
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ return ret;
+}
+
+/*
+ * Hashgen defined in 10.1.1.4
+ */
+static int drbg_hash_hashgen(struct drbg_state *drbg,
+ unsigned char *buf,
+ unsigned int buflen)
+{
+ int len = 0;
+ int ret = 0;
+ unsigned char *src = drbg->scratchpad;
+ unsigned char *dst = drbg->scratchpad + drbg_statelen(drbg);
+ struct drbg_string data;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ /* use the scratchpad as a lookaside buffer */
+ memset(src, 0, drbg_statelen(drbg));
+ memset(dst, 0, drbg_blocklen(drbg));
+
+ /* 10.1.1.4 step hashgen 2 */
+ memcpy(src, drbg->V, drbg_statelen(drbg));
+
+ drbg_string_fill(&data, src, drbg_statelen(drbg));
+ while (len < buflen) {
+ unsigned int outlen = 0;
+ /* 10.1.1.4 step hashgen 4.1 */
+ ret = drbg_kcapi_hash(drbg, NULL, dst, &data);
+ if (ret) {
+ len = ret;
+ goto out;
+ }
+ outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
+ drbg_blocklen(drbg) : (buflen - len);
+ if (!drbg_fips_continuous_test(drbg, dst)) {
+ drbg_add_buf(src, drbg_statelen(drbg), &prefix, 1);
+ continue;
+ }
+ /* 10.1.1.4 step hashgen 4.2 */
+ memcpy(buf + len, dst, outlen);
+ len += outlen;
+ /* 10.1.1.4 hashgen step 4.3 */
+ if (len < buflen)
+ drbg_add_buf(src, drbg_statelen(drbg), &prefix, 1);
+ }
+
+out:
+ memset(drbg->scratchpad, 0,
+ (drbg_statelen(drbg) + drbg_blocklen(drbg)));
+ return len;
+}
+
+/* generate function for Hash DRBG as defined in 10.1.1.4 */
+static int drbg_hash_generate(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ int len = 0;
+ int ret = 0;
+ unsigned char req[8];
+ unsigned char prefix = DRBG_PREFIX3;
+ struct drbg_string data1, data2;
+
+ /*
+ * scratchpad usage: drbg_hash_process_addtl uses the scratchpad, but
+ * fully completes before returning. Thus, we can reuse the scratchpad
+ */
+ /* 10.1.1.4 step 2 */
+ ret = drbg_hash_process_addtl(drbg, addtl);
+ if (ret)
+ return ret;
+ /* 10.1.1.4 step 3 -- invocation of the Hashgen function defined in
+ * 10.1.1.4 */
+ len = drbg_hash_hashgen(drbg, buf, buflen);
+
+ /* this is the value H as documented in 10.1.1.4 */
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ /* 10.1.1.4 step 4 */
+ drbg_string_fill(&data1, &prefix, 1);
+ drbg_string_fill(&data2, drbg->V, drbg_statelen(drbg));
+ data1.next = &data2;
+ ret = drbg_kcapi_hash(drbg, NULL, drbg->scratchpad, &data1);
+ if (ret) {
+ len = ret;
+ goto out;
+ }
+
+ /* 10.1.1.4 step 5 */
+ drbg_add_buf(drbg->V, drbg_statelen(drbg),
+ drbg->scratchpad, drbg_blocklen(drbg));
+ drbg_add_buf(drbg->V, drbg_statelen(drbg),
+ drbg->C, drbg_statelen(drbg));
+ drbg_int2byte(req, drbg->reseed_ctr, sizeof(req));
+ drbg_add_buf(drbg->V, drbg_statelen(drbg), req, 8);
+
+out:
+ memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
+ return len;
+}
+
+/*
+ * scratchpad usage: as update and generate are used isolated, both
+ * can use the scratchpad
+ */
+static struct drbg_state_ops drbg_hash_ops = {
+ .update = drbg_hash_update,
+ .generate = drbg_hash_generate,
+ .crypto_init = drbg_init_hash_kernel,
+ .crypto_fini = drbg_fini_hash_kernel,
+};
+#endif /* CONFIG_CRYPTO_DRBG_HASH */
+
+/******************************************************************
+ * Functions common for DRBG implementations
+ ******************************************************************/
+
+/*
+ * Seeding or reseeding of the DRBG
+ *
+ * @drbg: DRBG state struct
+ * @pers: personalization / additional information buffer
+ * @reseed: 0 for initial seed process, 1 for reseeding
+ *
+ * return:
+ * 0 on success
+ * error value otherwise
+ */
+static int drbg_seed(struct drbg_state *drbg, struct drbg_string *pers,
+ bool reseed)
+{
+ int ret = 0;
+ unsigned char *entropy = NULL;
+ size_t entropylen = 0;
+ struct drbg_string data1;
+
+ /* 9.1 / 9.2 / 9.3.1 step 3 */
+ if (pers && pers->len > (drbg_max_addtl(drbg))) {
+ pr_devel("DRBG: personalization string too long %lu\n",
+ pers->len);
+ return -EINVAL;
+ }
+
+ if (drbg->test_data && drbg->test_data->testentropy) {
+ drbg_string_fill(&data1, drbg->test_data->testentropy->buf,
+ drbg->test_data->testentropy->len);
+ pr_devel("DRBG: using test entropy\n");
+ } else {
+ /* Gather entropy equal to the security strength of the DRBG.
+ * With a derivation function, a nonce is required in addition
+ * to the entropy. A nonce must be at least 1/2 of the security
+ * strength of the DRBG in size. Thus, entropy * nonce is 3/2
+ * of the strength. The consideration of a nonce is only
+ * applicable during initial seeding. */
+ entropylen = drbg_sec_strength(drbg->core->flags);
+ if (!entropylen)
+ return -EFAULT;
+ if (!reseed)
+ /* make sure we round up strength/2 in
+ * case it is not divisible by 2 */
+ entropylen = ((entropylen + 1) / 2) * 3;
+ pr_devel("DRBG: (re)seeding with %zu bytes of entropy\n",
+ entropylen);
+ entropy = kzalloc(entropylen, GFP_KERNEL);
+ if (!entropy)
+ return -ENOMEM;
+ get_random_bytes(entropy, entropylen);
+ drbg_string_fill(&data1, entropy, entropylen);
+ }
+
+ /* concatenation of entropy with personalization str / addtl input)
+ * the variable pers is directly handed by the caller, check its
+ * contents whether it is appropriate */
+ if (pers && pers->buf && 0 < pers->len && NULL == pers->next) {
+ data1.next = pers;
+ pr_devel("DRBG: using personalization string\n");
+ }
+
+ ret = drbg->d_ops->update(drbg, &data1, reseed);
+ if (ret)
+ goto out;
+
+ drbg->seeded = true;
+ /* 10.1.1.2 / 10.1.1.3 step 5 */
+ drbg->reseed_ctr = 1;
+
+out:
+ if (entropy)
+ kzfree(entropy);
+ return ret;
+}
+
+/*
+ * Free all substructures in a DRBG state without the DRBG state structure
+ */
+static inline void drbg_dealloc_state(struct drbg_state *drbg)
+{
+ if (!drbg)
+ return;
+ if (drbg->V)
+ kzfree(drbg->V);
+ drbg->V = NULL;
+ if (drbg->C)
+ kzfree(drbg->C);
+ drbg->C = NULL;
+ if (drbg->scratchpad)
+ kzfree(drbg->scratchpad);
+ drbg->scratchpad = NULL;
+ drbg->reseed_ctr = 0;
+#ifdef CONFIG_CRYPTO_FIPS
+ if (drbg->prev)
+ kzfree(drbg->prev);
+ drbg->prev = NULL;
+ drbg->fips_primed = false;
+#endif
+}
+
+/*
+ * Allocate all sub-structures for a DRBG state
+ * The DRBG state structure must already be allocated
+ */
+static inline int drbg_alloc_state(struct drbg_state *drbg)
+{
+ int ret = -ENOMEM;
+ unsigned int sb_size = 0;
+
+ if (!drbg)
+ return -EINVAL;
+
+ drbg->V = kzalloc(drbg_statelen(drbg), GFP_KERNEL);
+ if (!drbg->V)
+ goto err;
+ drbg->C = kzalloc(drbg_statelen(drbg), GFP_KERNEL);
+ if (!drbg->C)
+ goto err;
+#ifdef CONFIG_CRYPTO_FIPS
+ drbg->prev = kzalloc(drbg_blocklen(drbg), GFP_KERNEL);
+ if (!drbg->prev)
+ goto err;
+ drbg->fips_primed = false;
+#endif
+ /* scratchpad is only generated for CTR and Hash */
+ if (drbg->core->flags & DRBG_HMAC)
+ sb_size = 0;
+ else if (drbg->core->flags & DRBG_CTR)
+ sb_size = drbg_statelen(drbg) + drbg_blocklen(drbg) + /* temp */
+ drbg_statelen(drbg) + /* df_data */
+ drbg_blocklen(drbg) + /* pad */
+ drbg_blocklen(drbg) + /* iv */
+ drbg_statelen(drbg); /* temp */
+ else
+ sb_size = drbg_statelen(drbg) + drbg_blocklen(drbg);
+
+ if (0 < sb_size) {
+ drbg->scratchpad = kzalloc(sb_size, GFP_KERNEL);
+ if (!drbg->scratchpad)
+ goto err;
+ }
+ spin_lock_init(&drbg->drbg_lock);
+ return 0;
+
+err:
+ drbg_dealloc_state(drbg);
+ return ret;
+}
+
+/*
+ * Strategy to avoid holding long term locks: generate a shadow copy of DRBG
+ * and perform all operations on this shadow copy. After finishing, restore
+ * the updated state of the shadow copy into original drbg state. This way,
+ * only the read and write operations of the original drbg state must be
+ * locked
+ */
+
+/*
+ * Copy the DRBG state
+ */
+static inline void drbg_copy_drbg(struct drbg_state *src,
+ struct drbg_state *dst)
+{
+ if (!src || !dst)
+ return;
+ memcpy(dst->V, src->V, drbg_statelen(src));
+ memcpy(dst->C, src->C, drbg_statelen(src));
+ dst->reseed_ctr = src->reseed_ctr;
+ /* no copy of scratchpad */
+ /* priv_data is initialized with call to crypto_init */
+ /* d_ops and core are set outside, as these parameters are const */
+ dst->seeded = src->seeded;
+ dst->pr = src->pr;
+#ifdef CONFIG_CRYPTO_FIPS
+ dst->fips_primed = src->fips_primed;
+ memcpy(dst->prev, src->prev, drbg_blocklen(src));
+#endif
+ /* test_data is set outside to prevent it being copied back */
+}
+/*
+ * Generate shadow copy of the DRBG state
+ */
+static int drbg_make_shadow(struct drbg_state *drbg, struct drbg_state **shadow)
+{
+ int ret = -ENOMEM;
+ struct drbg_state *tmp = NULL;
+
+ /* some sanity checks */
+ if (!drbg || !drbg->core || !drbg->V || !drbg->C) {
+ pr_devel("DRBG: attempt to generate shadow copy for "
+ "uninitialized DRBG state rejected\n");
+ return -EINVAL;
+ }
+ /* HMAC does not have a scratchpad */
+ if (!(drbg->core->flags & DRBG_HMAC) && NULL == drbg->scratchpad)
+ return -EINVAL;
+
+ tmp = kzalloc(sizeof(struct drbg_state), GFP_KERNEL);
+ if (!tmp)
+ return -ENOMEM;
+
+ /* read-only data as they are defined as const, no lock needed */
+ tmp->core = drbg->core;
+ tmp->d_ops = drbg->d_ops;
+
+ ret = drbg_alloc_state(tmp);
+ if (ret)
+ goto err;
+
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg_copy_drbg(drbg, tmp);
+ /* only make a link to the test buffer, as we only read that data */
+ tmp->test_data = drbg->test_data;
+ spin_unlock_bh(&drbg->drbg_lock);
+ *shadow = tmp;
+ return 0;
+
+err:
+ if (tmp)
+ kzfree(tmp);
+ return ret;
+}
+
+/*
+ * Restore shadow state into original DRBG state
+ */
+static void drbg_restore_shadow(struct drbg_state *drbg,
+ struct drbg_state **shadow)
+{
+ struct drbg_state *tmp = *shadow;
+
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg_copy_drbg(tmp, drbg);
+ spin_unlock_bh(&drbg->drbg_lock);
+ drbg_dealloc_state(tmp);
+ kzfree(tmp);
+ *shadow = NULL;
+}
+
+/*************************************************************************
+ * DRBG interface functions
+ *************************************************************************/
+
+/*
+ * DRBG generate function as required by SP800-90A - this function
+ * generates random numbers
+ *
+ * @drbg DRBG state handle
+ * @buf Buffer where to store the random numbers -- the buffer must already
+ * be pre-allocated by caller
+ * @buflen Length of output buffer - this value defines the number of random
+ * bytes pulled from DRBG
+ * @addtl Additional input that is mixed into state, may be NULL -- note
+ * the entropy is pulled by the DRBG internally unconditionally
+ * as defined in SP800-90A. The additional input is mixed into
+ * the state in addition to the pulled entropy.
+ *
+ * return: generated number of bytes
+ */
+static int drbg_generate(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ int len = 0;
+ struct drbg_state *shadow = NULL;
+
+ if (0 == buflen || !buf) {
+ pr_devel("DRBG: no output buffer provided\n");
+ return -EINVAL;
+ }
+ if (addtl && NULL == addtl->buf && 0 < addtl->len) {
+ pr_devel("DRBG: wrong format of additional information\n");
+ return -EINVAL;
+ }
+
+ len = drbg_make_shadow(drbg, &shadow);
+ if (len) {
+ pr_devel("DRBG: shadow copy cannot be generated\n");
+ return len;
+ }
+ /* 9.3.1 step 2 */
+ len = -EINVAL;
+ if (buflen > (drbg_max_request_bytes(shadow))) {
+ pr_devel("DRBG: requested random numbers too large %u\n",
+ buflen);
+ goto err;
+ }
+ /* 9.3.1 step 3 is implicit with the chosen DRBG */
+ /* 9.3.1 step 4 */
+ if (addtl && addtl->len > (drbg_max_addtl(shadow))) {
+ pr_devel("DRBG: additional information string too long %zu\n",
+ addtl->len);
+ goto err;
+ }
+ /* 9.3.1 step 5 is implicit with the chosen DRBG */
+ /* 9.3.1 step 6 and 9 supplemented by 9.3.2 step c -- the spec is a
+ * bit convoluted here, we make it simpler */
+ if ((drbg_max_requests(shadow)) < shadow->reseed_ctr)
+ shadow->seeded = false;
+
+ /* allocate cipher handle */
+ if (shadow->d_ops->crypto_init) {
+ len = shadow->d_ops->crypto_init(shadow);
+ if (len)
+ goto err;
+ }
+
+ if (shadow->pr || !shadow->seeded) {
+ pr_devel("DRBG: reseeding before generation (prediction "
+ "resistance: %s, state %s)\n",
+ drbg->pr ? "true" : "false",
+ drbg->seeded ? "seeded" : "unseeded");
+ /* 9.3.1 steps 7.1 through 7.3 */
+ len = drbg_seed(shadow, addtl, true);
+ if (len)
+ goto err;
+ /* 9.3.1 step 7.4 */
+ addtl = NULL;
+ }
+ /* 9.3.1 step 8 and 10 */
+ len = shadow->d_ops->generate(shadow, buf, buflen, addtl);
+
+ /* 10.1.1.4 step 6, 10.1.2.5 step 7, 10.2.1.5.2 step 7 */
+ shadow->reseed_ctr++;
+ if (0 >= len)
+ goto err;
+
+ /* 11.3.3 -- re-perform self tests after some generated random
+ * numbers, the chosen value after which self test is performed
+ * is arbitrary, but it should be reasonable */
+ /* Here we do not perform the self tests because of the following
+ * reasons: it is mathematically impossible that the initial self tests
+ * were successfully and the following are not. If the initial would
+ * pass and the following would not, the kernel integrity is violated.
+ * In this case, the entire kernel operation is questionable and it
+ * is unlikely that the integrity violation only affects to the
+ * correct operation of the DRBG.
+ */
+#if 0
+ if (shadow->reseed_ctr && !(shadow->reseed_ctr % 4096)) {
+ int err = 0;
+ pr_devel("DRBG: start to perform self test\n");
+ if (drbg->core->flags & DRBG_HMAC)
+ err = alg_test("drbg(pr(hmac(sha256)))",
+ "drbg(pr(hmac(sha256)))", 0, 0);
+ else if (drbg->core->flags & DRBG_CTR)
+ err = alg_test("drbg(pr(ctr(aes128)))",
+ "drbg(pr(ctr(aes128)))", 0, 0);
+ else
+ err = alg_test("drbg(pr(sha256))",
+ "drbg(pr(sha256))", 0, 0);
+ if (err) {
+ pr_err("DRBG: periodical self test failed\n");
+ /* uninstantiate implies that from now on, only errors
+ * are returned when reusing this DRBG cipher handle */
+ drbg_uninstantiate(drbg);
+ drbg_dealloc_state(shadow);
+ kzfree(shadow);
+ return 0;
+ } else {
+ pr_devel("DRBG: self test successful\n");
+ }
+ }
+#endif
+
+err:
+ if (shadow->d_ops->crypto_fini)
+ shadow->d_ops->crypto_fini(shadow);
+ drbg_restore_shadow(drbg, &shadow);
+ return len;
+}
+
+/*
+ * Wrapper around drbg_generate which can pull arbitrary long strings
+ * from the DRBG without hitting the maximum request limitation.
+ *
+ * Parameters: see drbg_generate
+ * Return codes: see drbg_generate -- if one drbg_generate request fails,
+ * the entire drbg_generate_long request fails
+ */
+static int drbg_generate_long(struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ int len = 0;
+ unsigned int slice = 0;
+ do {
+ int tmplen = 0;
+ unsigned int chunk = 0;
+ slice = ((buflen - len) / drbg_max_request_bytes(drbg));
+ chunk = slice ? drbg_max_request_bytes(drbg) : (buflen - len);
+ tmplen = drbg_generate(drbg, buf + len, chunk, addtl);
+ if (0 >= tmplen)
+ return tmplen;
+ len += tmplen;
+ } while (slice > 0);
+ return len;
+}
+
+/*
+ * DRBG instantiation function as required by SP800-90A - this function
+ * sets up the DRBG handle, performs the initial seeding and all sanity
+ * checks required by SP800-90A
+ *
+ * @drbg memory of state -- if NULL, new memory is allocated
+ * @pers Personalization string that is mixed into state, may be NULL -- note
+ * the entropy is pulled by the DRBG internally unconditionally
+ * as defined in SP800-90A. The additional input is mixed into
+ * the state in addition to the pulled entropy.
+ * @coreref reference to core
+ * @pr prediction resistance enabled
+ *
+ * return
+ * 0 on success
+ * error value otherwise
+ */
+static int drbg_instantiate(struct drbg_state *drbg, struct drbg_string *pers,
+ int coreref, bool pr)
+{
+ int ret = -ENOMEM;
+
+ pr_devel("DRBG: Initializing DRBG core %d with prediction resistance "
+ "%s\n", coreref, pr ? "enabled" : "disabled");
+ drbg->core = &drbg_cores[coreref];
+ drbg->pr = pr;
+ drbg->seeded = false;
+ switch (drbg->core->flags & DRBG_TYPE_MASK) {
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+ case DRBG_HMAC:
+ drbg->d_ops = &drbg_hmac_ops;
+ break;
+#endif /* CONFIG_CRYPTO_DRBG_HMAC */
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+ case DRBG_HASH:
+ drbg->d_ops = &drbg_hash_ops;
+ break;
+#endif /* CONFIG_CRYPTO_DRBG_HASH */
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+ case DRBG_CTR:
+ drbg->d_ops = &drbg_ctr_ops;
+ break;
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ /* 9.1 step 1 is implicit with the selected DRBG type -- see
+ * drbg_sec_strength() */
+
+ /* 9.1 step 2 is implicit as caller can select prediction resistance
+ * and the flag is copied into drbg->flags --
+ * all DRBG types support prediction resistance */
+
+ /* 9.1 step 4 is implicit in drbg_sec_strength */
+
+ /* no allocation of drbg as this is done by the kernel crypto API */
+ ret = drbg_alloc_state(drbg);
+ if (ret)
+ return ret;
+
+ ret = -EFAULT;
+ /* allocate cipher handle */
+ if (drbg->d_ops->crypto_init && drbg->d_ops->crypto_init(drbg))
+ goto err;
+ /* 9.1 step 6 through 11 */
+ ret = drbg_seed(drbg, pers, false);
+ /* deallocate cipher handle */
+ if (drbg->d_ops->crypto_fini)
+ drbg->d_ops->crypto_fini(drbg);
+ if (ret)
+ goto err;
+
+ return 0;
+
+err:
+ drbg_dealloc_state(drbg);
+ return ret;
+}
+
+/*
+ * DRBG uninstantiate function as required by SP800-90A - this function
+ * frees all buffers and the DRBG handle
+ *
+ * @drbg DRBG state handle
+ *
+ * return
+ * 0 on success
+ */
+static int drbg_uninstantiate(struct drbg_state *drbg)
+{
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg_dealloc_state(drbg);
+ /* no scrubbing of test_data -- this shall survive an uninstantiate */
+ spin_unlock_bh(&drbg->drbg_lock);
+ /* no freeing of drbg as this is done by the kernel crypto API */
+ return 0;
+}
+
+/*
+ * Helper function for setting the test data in the DRBG
+ *
+ * @drbg DRBG state handle
+ * @test_data test data to sets
+ */
+static inline void drbg_set_testdata(struct drbg_state *drbg,
+ struct drbg_test_data *test_data)
+{
+ if (!test_data || !test_data->testentropy)
+ return;
+ spin_lock_bh(&drbg->drbg_lock);
+ drbg->test_data = test_data;
+ spin_unlock_bh(&drbg->drbg_lock);
+}
+
+/***************************************************************
+ * Kernel crypto APi cipher invocations requested by DRBG
+ ***************************************************************/
+
+#if defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_HMAC)
+struct sdesc {
+ struct shash_desc shash;
+ char ctx[];
+};
+
+static int drbg_init_hash_kernel(struct drbg_state *drbg)
+{
+ struct sdesc *sdesc;
+ struct crypto_shash *tfm;
+
+ tfm = crypto_alloc_shash(drbg->core->backend_cra_name, 0, 0);
+ if (IS_ERR(tfm)) {
+ pr_info("DRBG: could not allocate digest TFM handle\n");
+ return PTR_ERR(tfm);
+ }
+ BUG_ON(drbg_blocklen(drbg) != crypto_shash_digestsize(tfm));
+ sdesc = kzalloc(sizeof(struct shash_desc) + crypto_shash_descsize(tfm),
+ GFP_KERNEL);
+ if (!sdesc) {
+ crypto_free_shash(tfm);
+ return -ENOMEM;
+ }
+
+ sdesc->shash.tfm = tfm;
+ sdesc->shash.flags = 0;
+ drbg->priv_data = sdesc;
+ return 0;
+}
+
+static int drbg_fini_hash_kernel(struct drbg_state *drbg)
+{
+ struct sdesc *sdesc = (struct sdesc *)drbg->priv_data;
+ if (sdesc) {
+ crypto_free_shash(sdesc->shash.tfm);
+ kzfree(sdesc);
+ }
+ drbg->priv_data = NULL;
+ return 0;
+}
+
+static int drbg_kcapi_hash(struct drbg_state *drbg, const unsigned char *key,
+ unsigned char *outval, const struct drbg_string *in)
+{
+ struct sdesc *sdesc = (struct sdesc *)drbg->priv_data;
+
+ if (key)
+ crypto_shash_setkey(sdesc->shash.tfm, key, drbg_statelen(drbg));
+ crypto_shash_init(&sdesc->shash);
+ for (; NULL != in; in = in->next)
+ crypto_shash_update(&sdesc->shash, in->buf, in->len);
+ return crypto_shash_final(&sdesc->shash, outval);
+}
+#endif /* (CONFIG_CRYPTO_DRBG_HASH || CONFIG_CRYPTO_DRBG_HMAC) */
+
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+static int drbg_init_sym_kernel(struct drbg_state *drbg)
+{
+ int ret = 0;
+ struct crypto_blkcipher *tfm;
+
+ tfm = crypto_alloc_blkcipher(drbg->core->backend_cra_name, 0, 0);
+ if (IS_ERR(tfm)) {
+ pr_info("DRBG: could not allocate cipher TFM handle\n");
+ return PTR_ERR(tfm);
+ }
+ BUG_ON(drbg_blocklen(drbg) != crypto_blkcipher_blocksize(tfm));
+ drbg->priv_data = tfm;
+ return ret;
+}
+
+static int drbg_fini_sym_kernel(struct drbg_state *drbg)
+{
+ struct crypto_blkcipher *tfm =
+ (struct crypto_blkcipher *)drbg->priv_data;
+ if (tfm)
+ crypto_free_blkcipher(tfm);
+ drbg->priv_data = NULL;
+ return 0;
+}
+
+static int drbg_kcapi_sym(struct drbg_state *drbg, const unsigned char *key,
+ unsigned char *outval, const struct drbg_string *in)
+{
+ int ret = 0;
+ struct scatterlist sg_in, sg_out;
+ struct blkcipher_desc desc;
+ struct crypto_blkcipher *tfm =
+ (struct crypto_blkcipher *)drbg->priv_data;
+
+ desc.tfm = tfm;
+ desc.flags = 0;
+ crypto_blkcipher_setkey(tfm, key, (drbg_keylen(drbg)));
+ /* in is only component */
+ sg_init_one(&sg_in, in->buf, in->len);
+ sg_init_one(&sg_out, outval, drbg_blocklen(drbg));
+ ret = crypto_blkcipher_encrypt(&desc, &sg_out, &sg_in, in->len);
+
+ return ret;
+}
+#endif /* CONFIG_CRYPTO_DRBG_CTR */
+
+/***************************************************************
+ * Kernel crypto API interface to register DRBG
+ ***************************************************************/
+
+/*
+ * Look up the DRBG flags by given kernel crypto API cra_name
+ * The code uses the drbg_cores definition to do this
+ *
+ * @cra_name kernel crypto API cra_name
+ * @coreref reference to integer which is filled with the pointer to
+ * the applicable core
+ * @pr reference for setting prediction resistance
+ *
+ * return: flags
+ */
+static inline void drbg_convert_tfm_core(const char *cra_name,
+ int *coreref, bool *pr)
+{
+ int i = 0;
+ size_t start = 0;
+ int len = 0;
+
+ *pr = true;
+ /* disassemble the names */
+ if (0 == memcmp(cra_name, "drbg(nopr(", 10)) {
+ start = 10;
+ *pr = false;
+ } else if (0 == memcmp(cra_name, "drbg(pr(", 8)) {
+ start = 8;
+ } else {
+ return;
+ }
+
+ /* remove the first part and the closing parenthesis */
+ len = strlen(cra_name) - start - 2;
+ for (i = 0; ARRAY_SIZE(drbg_cores) > i; i++) {
+ if (0 == memcmp(cra_name + start,
+ drbg_cores[i].cra_name, len)) {
+ *coreref = i;
+ return;
+ }
+ }
+}
+
+/*
+ * Initialize one DRBG invoked by the kernel crypto API
+ *
+ * Function uses the kernel crypto API cra_name to look up
+ * the flags to instantiate the DRBG
+ */
+static int drbg_kcapi_init(struct crypto_tfm *tfm)
+{
+ struct drbg_state *drbg = crypto_tfm_ctx(tfm);
+ bool pr = false;
+ int coreref = 0;
+
+ drbg_convert_tfm_core(crypto_tfm_alg_name(tfm), &coreref, &pr);
+ /* when personalization string is needed, the caller must call reset
+ * and provide the personalization string as seed information */
+ return drbg_instantiate(drbg, NULL, coreref, pr);
+}
+
+static void drbg_kcapi_cleanup(struct crypto_tfm *tfm)
+{
+ drbg_uninstantiate(crypto_tfm_ctx(tfm));
+}
+
+/*
+ * Generate random numbers invoked by the kernel crypto API:
+ * The API of the kernel crypto API is extended as follows:
+ *
+ * If dlen is larger than zero, rdata is interpreted as the output buffer
+ * where random data is to be stored.
+ *
+ * If dlen is zero, rdata is interpreted as a pointer to a struct drbg_gen
+ * which holds the additional information string that is used for the
+ * DRBG generation process. The output buffer that is to be used to store
+ * data is also pointed to by struct drbg_gen.
+ *
+ */
+static int drbg_kcapi_random(struct crypto_rng *tfm, u8 *rdata,
+ unsigned int dlen)
+{
+ struct drbg_state *drbg = crypto_rng_ctx(tfm);
+ if (0 < dlen) {
+ return drbg_generate_long(drbg, rdata, dlen, NULL);
+ } else {
+ struct drbg_gen *data = (struct drbg_gen *)rdata;
+ /* catch NULL pointer */
+ if (!data)
+ return 0;
+ drbg_set_testdata(drbg, data->test_data);
+ return drbg_generate_long(drbg, data->outbuf, data->outlen,
+ data->addtl);
+ }
+}
+
+/*
+ * Reset the DRBG invoked by the kernel crypto API
+ * The reset implies a full re-initialization of the DRBG. Similar to the
+ * generate function of drbg_kcapi_random, this function extends the
+ * kernel crypto API interface with struct drbg_gen
+ */
+static int drbg_kcapi_reset(struct crypto_rng *tfm, u8 *seed, unsigned int slen)
+{
+ struct drbg_state *drbg = crypto_rng_ctx(tfm);
+ struct crypto_tfm *tfm_base = crypto_rng_tfm(tfm);
+ bool pr = false;
+ struct drbg_string seed_string;
+ int coreref = 0;
+
+ drbg_uninstantiate(drbg);
+ drbg_convert_tfm_core(crypto_tfm_alg_name(tfm_base), &coreref, &pr);
+ if (0 < slen) {
+ drbg_string_fill(&seed_string, seed, slen);
+ return drbg_instantiate(drbg, &seed_string, coreref, pr);
+ } else {
+ struct drbg_gen *data = (struct drbg_gen *)seed;
+ /* allow invocation of API call with NULL, 0 */
+ if (!data)
+ return drbg_instantiate(drbg, NULL, coreref, pr);
+ drbg_set_testdata(drbg, data->test_data);
+ return drbg_instantiate(drbg, data->addtl, coreref, pr);
+ }
+}
+
+/***************************************************************
+ * Kernel module: code to load the module
+ ***************************************************************/
+
+/*
+ * Tests as defined in 11.3.2 in addition to the cipher tests: testing
+ * of the error handling.
+ *
+ * Note, testing of failing seed source as defined in 11.3.2 is not applicable
+ * as seed source of get_random_bytes does not fail.
+ * Note, testing the reseed counter is not done as an automatic reseeding
+ * is performed in drbg_generate when the reseed counter is too large.
+ */
+static inline int __init drbg_healthcheck_sanity(void)
+{
+#ifdef CONFIG_CRYPTO_FIPS
+ unsigned int len = 0;
+#define OUTBUFLEN 16
+ unsigned char buf[OUTBUFLEN];
+ struct drbg_state *drbg = NULL;
+ int ret = -EFAULT;
+ int rc = -EFAULT;
+ bool pr = false;
+ int coreref = 0;
+ struct drbg_string addtl;
+ size_t max_addtllen, max_request_bytes;
+
+ /* only perform test in FIPS mode */
+ if (0 == fips_enabled)
+ return 0;
+
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+ drbg_convert_tfm_core("drbg(nopr(ctr(aes128)))", &coreref, &pr);
+#elif CONFIG_CRYPTO_DRBG_HASH
+ drbg_convert_tfm_core("drbg(nopr(sha256)", &coreref, &pr);
+#else
+ drbg_convert_tfm_core("drbg(nopr(hmac(sha256)))", &coreref, &pr);
+#endif
+
+ drbg = kzalloc(sizeof(struct drbg_state), GFP_KERNEL);
+ if (!drbg)
+ return -ENOMEM;
+
+ /* if the following tests fail, it is likely that there is a buffer
+ * overflow as buf is much smaller than the requested or provided
+ * string lengths -- in case the error handling does not succeed
+ * we may get an OOPS. And we want to get an OOPS as this is a
+ * grave bug */
+
+ /* get a valid instance of DRBG for following tests */
+ ret = drbg_instantiate(drbg, NULL, coreref, pr);
+ if (ret) {
+ rc = ret;
+ goto outbuf;
+ }
+ max_addtllen = drbg_max_addtl(drbg);
+ max_request_bytes = drbg_max_request_bytes(drbg);
+ drbg_string_fill(&addtl, buf, max_addtllen + 1);
+ /* overflow addtllen with additonal info string */
+ len = drbg_generate(drbg, buf, OUTBUFLEN, &addtl);
+ BUG_ON(0 < len);
+ /* overflow max_bits */
+ len = drbg_generate(drbg, buf, (max_request_bytes + 1), NULL);
+ BUG_ON(0 < len);
+ drbg_uninstantiate(drbg);
+
+ /* overflow max addtllen with personalization string */
+ ret = drbg_instantiate(drbg, &addtl, coreref, pr);
+ BUG_ON(0 == ret);
+ /* test uninstantated DRBG */
+ len = drbg_generate(drbg, buf, (max_request_bytes + 1), NULL);
+ BUG_ON(0 < len);
+ /* all tests passed */
+ rc = 0;
+
+ pr_devel("DRBG: Sanity tests for failure code paths successfully "
+ "completed\n");
+
+ drbg_uninstantiate(drbg);
+outbuf:
+ kzfree(drbg);
+ return rc;
+#else /* CONFIG_CRYPTO_FIPS */
+ return 0;
+#endif /* CONFIG_CRYPTO_FIPS */
+}
+
+
+static struct crypto_alg drbg_algs[22];
+
+/*
+ * Fill the array drbg_algs used to register the different DRBGs
+ * with the kernel crypto API. To fill the array, the information
+ * from drbg_cores[] is used.
+ */
+static inline void __init drbg_fill_array(unsigned long i, unsigned long j,
+ int pr)
+{
+ int pos = 0;
+
+ memset(&drbg_algs[i], 0, sizeof(struct crypto_alg));
+ if (pr) {
+ memcpy(drbg_algs[i].cra_name, "drbg(pr(", 8);
+ memcpy(drbg_algs[i].cra_driver_name, "drbg_pr_", 8);
+ pos = 8;
+ } else {
+ memcpy(drbg_algs[i].cra_name, "drbg(nopr(", 10);
+ memcpy(drbg_algs[i].cra_driver_name, "drbg_nopr_", 10);
+ pos = 10;
+ }
+ memcpy(drbg_algs[i].cra_name + pos, drbg_cores[j].cra_name,
+ strlen(drbg_cores[j].cra_name));
+ memcpy(drbg_algs[i].cra_name + pos + strlen(drbg_cores[j].cra_name),
+ "))", 2);
+ memcpy(drbg_algs[i].cra_driver_name + pos,
+ drbg_cores[j].cra_driver_name,
+ strlen(drbg_cores[j].cra_driver_name));
+ drbg_algs[i].cra_priority = 100;
+ drbg_algs[i].cra_flags = CRYPTO_ALG_TYPE_RNG;
+ drbg_algs[i].cra_ctxsize = sizeof(struct drbg_state);
+ drbg_algs[i].cra_type = &crypto_rng_type;
+ drbg_algs[i].cra_module = THIS_MODULE;
+ drbg_algs[i].cra_init = drbg_kcapi_init;
+ drbg_algs[i].cra_exit = drbg_kcapi_cleanup;
+ drbg_algs[i].cra_u.rng.rng_make_random = drbg_kcapi_random;
+ drbg_algs[i].cra_u.rng.rng_reset = drbg_kcapi_reset;
+ drbg_algs[i].cra_u.rng.seedsize = 0;
+}
+
+static int __init drbg_init(void)
+{
+ unsigned int i = 0; /* pointer to drbg_algs */
+ unsigned int j = 0; /* pointer to drbg_cores */
+ int ret = -EFAULT;
+
+ ret = drbg_healthcheck_sanity();
+ if (ret)
+ return ret;
+
+ if (ARRAY_SIZE(drbg_cores) * 2 > ARRAY_SIZE(drbg_algs)) {
+ pr_info("DRBG: Cannot register all DRBG types"
+ "(slots needed: %lu, slots available: %lu)\n",
+ ARRAY_SIZE(drbg_cores) * 2, ARRAY_SIZE(drbg_algs));
+ return ret;
+ }
+
+ /* each DRBG definition can be used with PR and without PR, thus
+ * we instantiate each DRBG in drbg_cores[] twice */
+ for (j = 0; ARRAY_SIZE(drbg_cores) > j; j++) {
+ drbg_fill_array(i, j, 1);
+ i++;
+ drbg_fill_array(i, j, 0);
+ i++;
+ }
+ return crypto_register_algs(drbg_algs, (ARRAY_SIZE(drbg_cores) * 2));
+}
+
+void __exit drbg_exit(void)
+{
+ crypto_unregister_algs(drbg_algs, (ARRAY_SIZE(drbg_cores) * 2));
+}
+
+module_init(drbg_init);
+module_exit(drbg_exit);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Stephan Mueller <smueller@chronox.de>");
+MODULE_DESCRIPTION("NIST SP800-90A Deterministic Random Bit Generator (DRBG) using following cores:"
+#ifdef CONFIG_CRYPTO_DRBG_HMAC
+"HMAC "
+#endif
+#ifdef CONFIG_CRYPTO_DRBG_HASH
+"Hash "
+#endif
+#ifdef CONFIG_CRYPTO_DRBG_CTR
+"CTR"
+#endif
+);
^ permalink raw reply related [flat|nested] 29+ messages in thread* Re: [PATCH v6 1/6] SP800-90A Deterministic Random Bit Generator
2014-04-26 20:13 ` [PATCH v6 " Stephan Mueller
@ 2014-05-20 21:32 ` Rafael Aquini
0 siblings, 0 replies; 29+ messages in thread
From: Rafael Aquini @ 2014-05-20 21:32 UTC (permalink / raw)
To: Stephan Mueller
Cc: linux-kernel, linux-crypto, jeremy.wayne.powell, clemens, pwalten, joe
On Sat, Apr 26, 2014 at 10:13:08PM +0200, Stephan Mueller wrote:
> Changes v6:
> * change name of array cores to drbg_cores as suggested by Joe Perches
> * make drbg_cores static as suggested by Joe Perches
> * catch possible programming error regarding array overflow in drbg_algs gracefully
>
> Signed-off-by: Stephan Mueller <smueller@chronox.de>
> ---
> create mode 100644 crypto/drbg.c
>
> diff --git a/crypto/drbg.c b/crypto/drbg.c
> new file mode 100644
> index 0000000..cee4e1a
> --- /dev/null
> +++ b/crypto/drbg.c
> @@ -0,0 +1,2001 @@
> +/*
> + * DRBG: Deterministic Random Bits Generator
> + * Based on NIST Recommended DRBG from NIST SP800-90A with the following
> + * properties:
> + * * CTR DRBG with DF with AES-128, AES-192, AES-256 cores
> + * * Hash DRBG with DF with SHA-1, SHA-256, SHA-384, SHA-512 cores
> + * * HMAC DRBG with DF with SHA-1, SHA-256, SHA-384, SHA-512 cores
> + * * with and without prediction resistance
> + *
> + * Copyright Stephan Mueller <smueller@chronox.de>, 2014
> + *
> + * Redistribution and use in source and binary forms, with or without
> + * modification, are permitted provided that the following conditions
> + * are met:
> + * 1. Redistributions of source code must retain the above copyright
> + * notice, and the entire permission notice in its entirety,
> + * including the disclaimer of warranties.
> + * 2. Redistributions in binary form must reproduce the above copyright
> + * notice, this list of conditions and the following disclaimer in the
> + * documentation and/or other materials provided with the distribution.
> + * 3. The name of the author may not be used to endorse or promote
> + * products derived from this software without specific prior
> + * written permission.
> + *
> + * ALTERNATIVELY, this product may be distributed under the terms of
> + * the GNU General Public License, in which case the provisions of the GPL are
> + * required INSTEAD OF the above restrictions. (This clause is
> + * necessary due to a potential bad interaction between the GPL and
> + * the restrictions contained in a BSD-style copyright.)
> + *
> + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
> + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
> + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF
> + * WHICH ARE HEREBY DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE
> + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
> + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
> + * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
> + * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
> + * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
> + * USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH
> + * DAMAGE.
> + *
> + * DRBG Usage
> + * ==========
> + * The SP 800-90A DRBG allows the user to specify a personalization string
> + * for initialization as well as an additional information string for each
> + * random number request. The following code fragments show how a caller
> + * uses the kernel crypto API to use the full functionality of the DRBG.
> + *
> + * Usage without any additional data
> + * ---------------------------------
> + * struct crypto_rng *drng;
> + * int err;
> + * char data[DATALEN];
> + *
> + * drng = crypto_alloc_rng(drng_name, 0, 0);
> + * err = crypto_rng_get_bytes(drng, &data, DATALEN);
> + * crypto_free_rng(drng);
> + *
> + *
> + * Usage with personalization string during initialization
> + * -------------------------------------------------------
> + * struct crypto_rng *drng;
> + * int err;
> + * char data[DATALEN];
> + * struct drbg_string pers;
> + * char personalization[11] = "some-string";
> + *
> + * drbg_string_fill(&pers, personalization, strlen(personalization));
> + * drng = crypto_alloc_rng(drng_name, 0, 0);
> + * // The reset completely re-initializes the DRBG with the provided
> + * // personalization string
> + * err = crypto_rng_reset(drng, &personalization, strlen(personalization));
> + * err = crypto_rng_get_bytes(drng, &data, DATALEN);
> + * crypto_free_rng(drng);
> + *
> + *
> + * Usage with additional information string during random number request
> + * ---------------------------------------------------------------------
> + * struct crypto_rng *drng;
> + * int err;
> + * char data[DATALEN];
> + * char addtl_string[11] = "some-string";
> + * string drbg_string addtl;
> + *
> + * drbg_string_fill(&addtl, addtl_string, strlen(addtl_string));
> + * drng = crypto_alloc_rng(drng_name, 0, 0);
> + * // The following call is a wrapper to crypto_rng_get_bytes() and returns
> + * // the same error codes.
> + * err = crypto_drbg_get_bytes_addtl(drng, &data, DATALEN, &addtl);
> + * crypto_free_rng(drng);
> + *
> + *
> + * Usage with personalization and additional information strings
> + * -------------------------------------------------------------
> + * Just mix both scenarios above.
> + */
> +
> +#include <crypto/drbg.h>
> +
> +#if !defined(CONFIG_CRYPTO_DRBG_HASH) && \
> + !defined(CONFIG_CRYPTO_DRBG_HMAC) && \
> + !defined(CONFIG_CRYPTO_DRBG_CTR)
> +#warning "The DRBG code is useless without compiling at least one DRBG type"
> +#endif
> +
> +/***************************************************************
> + * Backend cipher definitions available to DRBG
> + ***************************************************************/
> +
> +static const struct drbg_core drbg_cores[] = {
> + /* Hash DRBGs */
> +#ifdef CONFIG_CRYPTO_DRBG_HASH
> + {
> + .flags = DRBG_HASH | DRBG_STRENGTH128,
> + .statelen = 55, /* 440 bits */
> + .max_addtllen = 35,
> + .max_bits = 19,
> + .max_req = 48,
> + .blocklen_bytes = 20,
> + .cra_name = "sha1",
> + .cra_driver_name = "sha1",
> + .backend_cra_name = "sha1",
> + }, {
> + .flags = DRBG_HASH | DRBG_STRENGTH256,
> + .statelen = 55, /* 440 bits */
> + .max_addtllen = 35,
> + .max_bits = 19,
> + .max_req = 48,
> + .blocklen_bytes = 32,
> + .cra_name = "sha256",
> + .cra_driver_name = "sha256",
> + .backend_cra_name = "sha256",
> + }, {
> + .flags = DRBG_HASH | DRBG_STRENGTH256,
> + .statelen = 111, /* 888 bits */
> + .max_addtllen = 35,
> + .max_bits = 19,
> + .max_req = 48,
> + .blocklen_bytes = 48,
> + .cra_name = "sha384",
> + .cra_driver_name = "sha384",
> + .backend_cra_name = "sha384",
> + }, {
> + .flags = DRBG_HASH | DRBG_STRENGTH256,
> + .statelen = 111, /* 888 bits */
> + .max_addtllen = 35,
> + .max_bits = 19,
> + .max_req = 48,
> + .blocklen_bytes = 64,
> + .cra_name = "sha512",
> + .cra_driver_name = "sha512",
> + .backend_cra_name = "sha512",
> + },
> +#endif /* CONFIG_CRYPTO_DRBG_HASH */
> +#ifdef CONFIG_CRYPTO_DRBG_HMAC
> + {
> + /* HMAC DRBGs */
> + .flags = DRBG_HMAC | DRBG_STRENGTH256,
> + .statelen = 20, /* block length of cipher */
> + .max_addtllen = 35,
> + .max_bits = 19,
> + .max_req = 48,
> + .blocklen_bytes = 20,
> + .cra_name = "hmac(sha1)",
> + .cra_driver_name = "hmac_sha1",
> + .backend_cra_name = "hmac(sha1)",
> + }, {
> + .flags = DRBG_HMAC | DRBG_STRENGTH256,
> + .statelen = 32, /* block length of cipher */
> + .max_addtllen = 35,
> + .max_bits = 19,
> + .max_req = 48,
> + .blocklen_bytes = 32,
> + .cra_name = "hmac(sha256)",
> + .cra_driver_name = "hmac_sha256",
> + .backend_cra_name = "hmac(sha256)",
> + }, {
> + .flags = DRBG_HMAC | DRBG_STRENGTH256,
> + .statelen = 48, /* block length of cipher */
> + .max_addtllen = 35,
> + .max_bits = 19,
> + .max_req = 48,
> + .blocklen_bytes = 48,
> + .cra_name = "hmac(sha384)",
> + .cra_driver_name = "hmac_sha384",
> + .backend_cra_name = "hmac(sha384)",
> + }, {
> + .flags = DRBG_HMAC | DRBG_STRENGTH256,
> + .statelen = 64, /* block length of cipher */
> + .max_addtllen = 35,
> + .max_bits = 19,
> + .max_req = 48,
> + .blocklen_bytes = 64,
> + .cra_name = "hmac(sha512)",
> + .cra_driver_name = "hmac_sha512",
> + .backend_cra_name = "hmac(sha512)",
> + },
> +#endif /* CONFIG_CRYPTO_DRBG_HMAC */
> +#ifdef CONFIG_CRYPTO_DRBG_CTR
> + {
> + /* block ciphers */
> + .flags = DRBG_CTR | DRBG_STRENGTH128,
> + .statelen = 32, /* 256 bits as defined in 10.2.1 */
> + .max_addtllen = 35,
> + .max_bits = 19,
> + .max_req = 48,
> + .blocklen_bytes = 16,
> + .cra_name = "ctr(aes128)",
> + .cra_driver_name = "ctr_aes128",
> + .backend_cra_name = "ecb(aes)",
> + }, {
> + /* block ciphers */
> + .flags = DRBG_CTR | DRBG_STRENGTH192,
> + .statelen = 40, /* 320 bits as defined in 10.2.1 */
> + .max_addtllen = 35,
> + .max_bits = 19,
> + .max_req = 48,
> + .blocklen_bytes = 16,
> + .cra_name = "ctr(aes192)",
> + .cra_driver_name = "ctr_aes192",
> + .backend_cra_name = "ecb(aes)",
> + }, {
> + /* block ciphers */
> + .flags = DRBG_CTR | DRBG_STRENGTH256,
> + .statelen = 48, /* 384 bits as defined in 10.2.1 */
> + .max_addtllen = 35,
> + .max_bits = 19,
> + .max_req = 48,
> + .blocklen_bytes = 16,
> + .cra_name = "ctr(aes256)",
> + .cra_driver_name = "ctr_aes256",
> + .backend_cra_name = "ecb(aes)",
> + },
> +#endif /* CONFIG_CRYPTO_DRBG_CTR */
> +};
> +
> +/******************************************************************
> + * Generic helper functions
> + ******************************************************************/
> +
> +/*
> + * Return strength of DRBG according to SP800-90A section 8.4
> + *
> + * @flags DRBG flags reference
> + *
> + * Return: normalized strength in *bytes* value or 32 as default
> + * to counter programming errors
> + */
> +static inline unsigned short drbg_sec_strength(drbg_flag_t flags)
> +{
> + switch (flags & DRBG_STRENGTH_MASK) {
> + case DRBG_STRENGTH128:
> + return 16;
> + case DRBG_STRENGTH192:
> + return 24;
> + case DRBG_STRENGTH256:
> + return 32;
> + default:
> + return 32;
> + }
> +}
> +
> +/*
> + * FIPS 140-2 continuous self test
> + * The test is performed on the result of one round of the output
> + * function. Thus, the function implicitly knows the size of the
> + * buffer.
> + *
> + * The FIPS test can be called in an endless loop until it returns
> + * true. Although the code looks like a potential for a deadlock, it
> + * is not the case, because returning a false cannot mathematically
> + * occur (except once when a reseed took place and the updated state
> + * would is now set up such that the generation of new value returns
> + * an identical one -- this is most unlikely and would happen only once).
> + * Thus, if this function repeatedly returns false and thus would cause
> + * a deadlock, the integrity of the entire kernel is lost.
> + *
> + * @drbg DRBG handle
> + * @buf output buffer of random data to be checked
> + *
> + * return:
> + * true on success
> + * false on error
> + */
> +static bool drbg_fips_continuous_test(struct drbg_state *drbg,
> + const unsigned char *buf)
> +{
> +#ifdef CONFIG_CRYPTO_FIPS
> + int ret = 0;
> + /* skip test if we test the overall system */
> + if (drbg->test_data)
> + return true;
> + /* only perform test in FIPS mode */
> + if (0 == fips_enabled)
> + return true;
> + if (!drbg->fips_primed) {
> + /* Priming of FIPS test */
> + memcpy(drbg->prev, buf, drbg_blocklen(drbg));
> + drbg->fips_primed = true;
> + /* return false due to priming, i.e. another round is needed */
> + return false;
> + }
> + ret = memcmp(drbg->prev, buf, drbg_blocklen(drbg));
> + memcpy(drbg->prev, buf, drbg_blocklen(drbg));
> + /* the test shall pass when the two compared values are not equal */
> + return ret != 0;
> +#else
> + return true;
> +#endif /* CONFIG_CRYPTO_FIPS */
> +}
> +
> +/*
> + * Convert an integer into a byte representation of this integer.
> + * The byte representation is big-endian
> + *
> + * @buf buffer holding the converted integer
> + * @val value to be converted
> + * @buflen length of buffer
> + */
> +#if (defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_CTR))
> +static inline void drbg_int2byte(unsigned char *buf, uint64_t val,
> + size_t buflen)
> +{
> + unsigned char *byte;
> + uint64_t i;
> +
> + byte = buf + (buflen - 1);
> + for (i = 0; i < buflen; i++)
> + *(byte--) = val >> (i * 8) & 0xff;
> +}
> +
> +/*
> + * Increment buffer
> + *
> + * @dst buffer to increment
> + * @add value to add
> + */
> +static inline void drbg_add_buf(unsigned char *dst, size_t dstlen,
> + const unsigned char *add, size_t addlen)
> +{
> + /* implied: dstlen > addlen */
> + unsigned char *dstptr;
> + const unsigned char *addptr;
> + unsigned int remainder = 0;
> + size_t len = addlen;
> +
> + dstptr = dst + (dstlen-1);
> + addptr = add + (addlen-1);
> + while (len) {
> + remainder += *dstptr + *addptr;
> + *dstptr = remainder & 0xff;
> + remainder >>= 8;
> + len--; dstptr--; addptr--;
> + }
> + len = dstlen - addlen;
> + while (len && remainder > 0) {
> + remainder = *dstptr + 1;
> + *dstptr = remainder & 0xff;
> + remainder >>= 8;
> + len--; dstptr--;
> + }
> +}
> +#endif /* defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_CTR) */
> +
> +/******************************************************************
> + * CTR DRBG callback functions
> + ******************************************************************/
> +
> +#ifdef CONFIG_CRYPTO_DRBG_CTR
> +static int drbg_kcapi_sym(struct drbg_state *drbg, const unsigned char *key,
> + unsigned char *outval, const struct drbg_string *in);
> +static int drbg_init_sym_kernel(struct drbg_state *drbg);
> +static int drbg_fini_sym_kernel(struct drbg_state *drbg);
> +
> +/* BCC function for CTR DRBG as defined in 10.4.3 */
> +static int drbg_ctr_bcc(struct drbg_state *drbg,
> + unsigned char *out, const unsigned char *key,
> + struct drbg_string *in)
> +{
> + int ret = -EFAULT;
> + struct drbg_string *curr = in;
> + size_t inpos = curr->len;
> + const unsigned char *pos = curr->buf;
> + struct drbg_string data;
> +
> + drbg_string_fill(&data, out, drbg_blocklen(drbg));
> +
> + /* 10.4.3 step 1 */
> + memset(out, 0, drbg_blocklen(drbg));
> +
> + /* 10.4.3 step 2 / 4 */
> + while (inpos) {
> + short cnt = 0;
> + /* 10.4.3 step 4.1 */
> + for (cnt = 0; cnt < drbg_blocklen(drbg); cnt++) {
> + out[cnt] ^= *pos;
> + pos++; inpos--;
> + /* the following branch implements the linked list
> + * iteration. If we are at the end of the current data
> + * set, we have to start using the next data set if
> + * available -- the inpos value always points to the
> + * current byte and will be zero if we have processed
> + * the last byte of the last linked list member */
> + if (0 == inpos) {
> + curr = curr->next;
> + if (NULL != curr) {
> + pos = curr->buf;
> + inpos = curr->len;
> + } else {
> + inpos = 0;
> + break;
> + }
> + }
> + }
> + /* 10.4.3 step 4.2 */
> + ret = drbg_kcapi_sym(drbg, key, out, &data);
> + if (ret)
> + return ret;
> + /* 10.4.3 step 2 */
> + }
> + return 0;
> +}
> +
> +/*
> + * scratchpad usage: drbg_ctr_update is interlinked with drbg_ctr_df
> + * (and drbg_ctr_bcc, but this function does not need any temporary buffers),
> + * the scratchpad is used as follows:
> + * drbg_ctr_update:
> + * temp
> + * start: drbg->scratchpad
> + * length: drbg_statelen(drbg) + drbg_blocklen(drbg)
> + * note: the cipher writing into this variable works
> + * blocklen-wise. Now, when the statelen is not a multiple
> + * of blocklen, the generateion loop below "spills over"
> + * by at most blocklen. Thus, we need to give sufficient
> + * memory.
> + * df_data
> + * start: drbg->scratchpad +
> + * drbg_statelen(drbg) + drbg_blocklen(drbg)
> + * length: drbg_statelen(drbg)
> + *
> + * drbg_ctr_df:
> + * pad
> + * start: df_data + drbg_statelen(drbg)
> + * length: drbg_blocklen(drbg)
> + * iv
> + * start: pad + drbg_blocklen(drbg)
> + * length: drbg_blocklen(drbg)
> + * temp
> + * start: iv + drbg_blocklen(drbg)
> + * length: (drbg_keylen(drbg) + drbg_blocklen(drbg) ==
> + * drbg_statelen(drbg))
> + */
> +
> +/* Derivation Function for CTR DRBG as defined in 10.4.2 */
> +static int drbg_ctr_df(struct drbg_state *drbg,
> + unsigned char *df_data, size_t bytes_to_return,
> + struct drbg_string *addtl)
> +{
> + int ret = -EFAULT;
> + unsigned char L_N[8];
> + /* S3 is input */
> + struct drbg_string S1, S2, S4, cipherin;
> + struct drbg_string *tempstr = addtl;
> + unsigned char *pad = df_data + drbg_statelen(drbg);
> + unsigned char *iv = pad + drbg_blocklen(drbg);
> + unsigned char *temp = iv + drbg_blocklen(drbg);
> + size_t padlen = 0;
> + unsigned int templen = 0;
> + /* 10.4.2 step 7 */
> + unsigned int i = 0;
> + /* 10.4.2 step 8 */
> + const unsigned char *K = (unsigned char *)
> + "\x00\x01\x02\x03\x04\x05\x06\x07"
> + "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f"
> + "\x10\x11\x12\x13\x14\x15\x16\x17"
> + "\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f";
> + unsigned char *X;
> + size_t generated_len = 0;
> + size_t inputlen = 0;
> +
> + memset(pad, 0, drbg_blocklen(drbg));
> + memset(iv, 0, drbg_blocklen(drbg));
> + memset(temp, 0, drbg_statelen(drbg));
> +
> + /* 10.4.2 step 1 is implicit as we work byte-wise */
> +
> + /* 10.4.2 step 2 */
> + if ((512/8) < bytes_to_return)
> + return -EINVAL;
> +
> + /* 10.4.2 step 2 -- calculate the entire length of all input data */
> + for (; NULL != tempstr; tempstr = tempstr->next)
> + inputlen += tempstr->len;
> + drbg_int2byte(&L_N[0], inputlen, 4);
> +
> + /* 10.4.2 step 3 */
> + drbg_int2byte(&L_N[4], bytes_to_return, 4);
> +
> + /* 10.4.2 step 5: length is L_N, input_string, one byte, padding */
> + padlen = (inputlen + sizeof(L_N) + 1) % (drbg_blocklen(drbg));
> + /* wrap the padlen appropriately */
> + if (padlen)
> + padlen = drbg_blocklen(drbg) - padlen;
> + /* pad / padlen contains the 0x80 byte and the following zero bytes, so
> + * add one for byte for 0x80 */
weird multiline commentary style above, better switch to the standard:
/*
* line a
* line b
*/
> + padlen++;
> + pad[0] = 0x80;
> +
> + /* 10.4.2 step 4 -- first fill the linked list and then order it */
> + drbg_string_fill(&S1, iv, drbg_blocklen(drbg));
> + drbg_string_fill(&S2, L_N, sizeof(L_N));
> + drbg_string_fill(&S4, pad, padlen);
> + S1.next = &S2;
> + S2.next = addtl;
> + /* splice in addtl between S2 and S4 -- we place S4 at the end of the
> + * input data chain */
ditto
> + tempstr = addtl;
> + for (; NULL != tempstr; tempstr = tempstr->next)
> + if (NULL == tempstr->next)
> + break;
> + tempstr->next = &S4;
> +
> + /* 10.4.2 step 9 */
> + while (templen < (drbg_keylen(drbg) + (drbg_blocklen(drbg)))) {
> + /* 10.4.2 step 9.1 - the padding is implicit as the buffer
> + * holds zeros after allocation -- even the increment of i
> + * is irrelevant as the increment remains within length of i */
ditto
> + drbg_int2byte(iv, i, 4);
> + /* 10.4.2 step 9.2 -- BCC and concatenation with temp */
> + ret = drbg_ctr_bcc(drbg, temp + templen, K, &S1);
> + if (ret)
> + goto out;
> + /* 10.4.2 step 9.3 */
> + i++;
> + templen += drbg_blocklen(drbg);
> + }
> +
> + /* 10.4.2 step 11 */
> + /* implicit key len with seedlen - blocklen according to table 3 */
ditto
> + X = temp + (drbg_keylen(drbg));
> + drbg_string_fill(&cipherin, X, drbg_blocklen(drbg));
> +
> + /* 10.4.2 step 12: overwriting of outval */
> +
> + /* 10.4.2 step 13 */
ditto
Well, I won't go down pointing to every single occurrence of
new-and-out-of-standard multiline comments. Yeah, these are nitpicks,
but coding style is something we must strive to keep consistent accross
such big project as the linux kernel. Please, review your code and
adjust its style according to Documentation/CodingStyle.
Also, please consider doing a fresh re-submission of all your patches
(with respecting changelogs) as it's getting confusing to identify what
needs reviewer follow up on this thread.
Regards!
-- Rafael
> + while (generated_len < bytes_to_return) {
> + short blocklen = 0;
> + /* 10.4.2 step 13.1 */
> + /* the truncation of the key length is implicit as the key
> + * is only drbg_blocklen in size -- check for the implementation
> + * of the cipher function callback */
> + ret = drbg_kcapi_sym(drbg, temp, X, &cipherin);
> + if (ret)
> + goto out;
> + blocklen = (drbg_blocklen(drbg) <
> + (bytes_to_return - generated_len)) ?
> + drbg_blocklen(drbg) :
> + (bytes_to_return - generated_len);
> + /* 10.4.2 step 13.2 and 14 */
> + memcpy(df_data + generated_len, X, blocklen);
> + generated_len += blocklen;
> + }
> +
> + ret = 0;
> +
> +out:
> + memset(iv, 0, drbg_blocklen(drbg));
> + memset(temp, 0, drbg_statelen(drbg));
> + memset(pad, 0, drbg_blocklen(drbg));
> + return ret;
> +}
> +
> +/* update function of CTR DRBG as defined in 10.2.1.2 */
> +static int drbg_ctr_update(struct drbg_state *drbg,
> + struct drbg_string *addtl, int reseed)
> +{
> + int ret = -EFAULT;
> + /* 10.2.1.2 step 1 */
> + unsigned char *temp = drbg->scratchpad;
> + unsigned char *df_data = drbg->scratchpad + drbg_statelen(drbg) +
> + drbg_blocklen(drbg);
> + unsigned char *temp_p, *df_data_p; /* pointer to iterate over buffers */
> + unsigned int len = 0;
> + struct drbg_string cipherin;
> + unsigned char prefix = DRBG_PREFIX1;
> +
> + memset(temp, 0, drbg_statelen(drbg) + drbg_blocklen(drbg));
> + memset(df_data, 0, drbg_statelen(drbg));
> +
> + /* 10.2.1.3.2 step 2 and 10.2.1.4.2 step 2 */
> + if (addtl && 0 < addtl->len) {
> + ret = drbg_ctr_df(drbg, df_data, drbg_statelen(drbg),
> + addtl);
> + if (ret)
> + goto out;
> + }
> +
> + drbg_string_fill(&cipherin, drbg->V, drbg_blocklen(drbg));
> + /* 10.2.1.3.2 step 2 and 3 -- are already covered as we memset(0)
> + * all memory during initialization */
> + while (len < (drbg_statelen(drbg))) {
> + /* 10.2.1.2 step 2.1 */
> + drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
> + /* 10.2.1.2 step 2.2 */
> + /* using target of temp + len: 10.2.1.2 step 2.3 and 3 */
> + ret = drbg_kcapi_sym(drbg, drbg->C, temp + len, &cipherin);
> + if (ret)
> + goto out;
> + /* 10.2.1.2 step 2.3 and 3 */
> + len += drbg_blocklen(drbg);
> + }
> +
> + /* 10.2.1.2 step 4 */
> + temp_p = temp;
> + df_data_p = df_data;
> + for (len = 0; len < drbg_statelen(drbg); len++) {
> + *temp_p ^= *df_data_p;
> + df_data_p++; temp_p++;
> + }
> +
> + /* 10.2.1.2 step 5 */
> + memcpy(drbg->C, temp, drbg_keylen(drbg));
> + /* 10.2.1.2 step 6 */
> + memcpy(drbg->V, temp + drbg_keylen(drbg), drbg_blocklen(drbg));
> + ret = 0;
> +
> +out:
> + memset(temp, 0, drbg_statelen(drbg) + drbg_blocklen(drbg));
> + memset(df_data, 0, drbg_statelen(drbg));
> + return ret;
> +}
> +
> +/*
> + * scratchpad use: drbg_ctr_update is called independently from
> + * drbg_ctr_extract_bytes. Therefore, the scratchpad is reused
> + */
> +/* Generate function of CTR DRBG as defined in 10.2.1.5.2 */
> +static int drbg_ctr_generate(struct drbg_state *drbg,
> + unsigned char *buf, unsigned int buflen,
> + struct drbg_string *addtl)
> +{
> + int len = 0;
> + int ret = 0;
> + struct drbg_string data;
> + unsigned char prefix = DRBG_PREFIX1;
> +
> + memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
> +
> + /* 10.2.1.5.2 step 2 */
> + if (addtl && 0 < addtl->len) {
> + addtl->next = NULL;
> + ret = drbg_ctr_update(drbg, addtl, 1);
> + if (ret)
> + return 0;
> + }
> +
> + /* 10.2.1.5.2 step 4.1 */
> + drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
> + drbg_string_fill(&data, drbg->V, drbg_blocklen(drbg));
> + while (len < buflen) {
> + int outlen = 0;
> + /* 10.2.1.5.2 step 4.2 */
> + ret = drbg_kcapi_sym(drbg, drbg->C, drbg->scratchpad, &data);
> + if (ret) {
> + len = ret;
> + goto out;
> + }
> + outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
> + drbg_blocklen(drbg) : (buflen - len);
> + if (!drbg_fips_continuous_test(drbg, drbg->scratchpad)) {
> + /* 10.2.1.5.2 step 6 */
> + drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
> + continue;
> + }
> + /* 10.2.1.5.2 step 4.3 */
> + memcpy(buf + len, drbg->scratchpad, outlen);
> + len += outlen;
> + /* 10.2.1.5.2 step 6 */
> + if (len < buflen)
> + drbg_add_buf(drbg->V, drbg_blocklen(drbg), &prefix, 1);
> + }
> +
> + /* 10.2.1.5.2 step 6 */
> + /*TODO the DF function is called again since according to step
> + * 2, the "additional_input" after step 2 is the output of the DF
> + * function -- when we save the DF output as a replacement
> + * for the addtl_input data, we do not need to call the DF again here */
> + if (addtl)
> + addtl->next = NULL;
> + ret = drbg_ctr_update(drbg, addtl, 1);
> + if (ret)
> + len = ret;
> +
> +out:
> + memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
> + return len;
> +}
> +
> +static struct drbg_state_ops drbg_ctr_ops = {
> + .update = drbg_ctr_update,
> + .generate = drbg_ctr_generate,
> + .crypto_init = drbg_init_sym_kernel,
> + .crypto_fini = drbg_fini_sym_kernel,
> +};
> +#endif /* CONFIG_CRYPTO_DRBG_CTR */
> +
> +/******************************************************************
> + * HMAC DRBG callback functions
> + ******************************************************************/
> +
> +#if defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_HMAC)
> +static int drbg_kcapi_hash(struct drbg_state *drbg, const unsigned char *key,
> + unsigned char *outval, const struct drbg_string *in);
> +static int drbg_init_hash_kernel(struct drbg_state *drbg);
> +static int drbg_fini_hash_kernel(struct drbg_state *drbg);
> +#endif /* (CONFIG_CRYPTO_DRBG_HASH || CONFIG_CRYPTO_DRBG_HMAC) */
> +
> +#ifdef CONFIG_CRYPTO_DRBG_HMAC
> +/* update function of HMAC DRBG as defined in 10.1.2.2 */
> +static int drbg_hmac_update(struct drbg_state *drbg,
> + struct drbg_string *seed, int reseed)
> +{
> + int ret = -EFAULT;
> + int i = 0;
> + struct drbg_string seed1, seed2, cipherin;
> +
> + if (!reseed) {
> + /* 10.1.2.3 step 2 already implicitly covered with
> + * the initial memset(0) of drbg->C */
> + memset(drbg->C, 0, drbg_statelen(drbg));
> + memset(drbg->V, 1, drbg_statelen(drbg));
> + }
> +
> + /* build linked list which implements the concatenation and fill
> + * first part*/
> + drbg_string_fill(&seed1, drbg->V, drbg_statelen(drbg));
> + /* buffer will be filled in for loop below with one byte */
> + drbg_string_fill(&seed2, NULL, 1);
> + seed1.next = &seed2;
> + /* seed may be NULL */
> + seed2.next = seed;
> +
> + drbg_string_fill(&cipherin, drbg->V, drbg_statelen(drbg));
> + /* we execute two rounds of V/K massaging */
> + for (i = 2; 0 < i; i--) {
> + /* first round uses 0x0, second 0x1 */
> + unsigned char prefix = DRBG_PREFIX0;
> + if (1 == i)
> + prefix = DRBG_PREFIX1;
> + /* 10.1.2.2 step 1 and 4 -- concatenation and HMAC for key */
> + seed2.buf = &prefix;
> + ret = drbg_kcapi_hash(drbg, drbg->C, drbg->C, &seed1);
> + if (ret)
> + return ret;
> +
> + /* 10.1.2.2 step 2 and 5 -- HMAC for V */
> + ret = drbg_kcapi_hash(drbg, drbg->C, drbg->V, &cipherin);
> + if (ret)
> + return ret;
> +
> + /* 10.1.2.2 step 3 */
> + if (!seed || 0 == seed->len)
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +/* generate function of HMAC DRBG as defined in 10.1.2.5 */
> +static int drbg_hmac_generate(struct drbg_state *drbg,
> + unsigned char *buf,
> + unsigned int buflen,
> + struct drbg_string *addtl)
> +{
> + int len = 0;
> + int ret = 0;
> + struct drbg_string data;
> +
> + /* 10.1.2.5 step 2 */
> + if (addtl && 0 < addtl->len) {
> + addtl->next = NULL;
> + ret = drbg_hmac_update(drbg, addtl, 1);
> + if (ret)
> + return ret;
> + }
> +
> + drbg_string_fill(&data, drbg->V, drbg_statelen(drbg));
> + while (len < buflen) {
> + unsigned int outlen = 0;
> + /* 10.1.2.5 step 4.1 */
> + ret = drbg_kcapi_hash(drbg, drbg->C, drbg->V, &data);
> + if (ret)
> + return ret;
> + outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
> + drbg_blocklen(drbg) : (buflen - len);
> + if (!drbg_fips_continuous_test(drbg, drbg->V))
> + continue;
> +
> + /* 10.1.2.5 step 4.2 */
> + memcpy(buf + len, drbg->V, outlen);
> + len += outlen;
> + }
> +
> + /* 10.1.2.5 step 6 */
> + if (addtl)
> + addtl->next = NULL;
> + ret = drbg_hmac_update(drbg, addtl, 1);
> + if (ret)
> + return ret;
> +
> + return len;
> +}
> +
> +static struct drbg_state_ops drbg_hmac_ops = {
> + .update = drbg_hmac_update,
> + .generate = drbg_hmac_generate,
> + .crypto_init = drbg_init_hash_kernel,
> + .crypto_fini = drbg_fini_hash_kernel,
> +
> +};
> +#endif /* CONFIG_CRYPTO_DRBG_HMAC */
> +
> +/******************************************************************
> + * Hash DRBG callback functions
> + ******************************************************************/
> +
> +#ifdef CONFIG_CRYPTO_DRBG_HASH
> +/*
> + * scratchpad usage: as drbg_hash_update and drbg_hash_df are used
> + * interlinked, the scratchpad is used as follows:
> + * drbg_hash_update
> + * start: drbg->scratchpad
> + * length: drbg_statelen(drbg)
> + * drbg_hash_df:
> + * start: drbg->scratchpad + drbg_statelen(drbg)
> + * length: drbg_blocklen(drbg)
> + */
> +/* Derivation Function for Hash DRBG as defined in 10.4.1 */
> +static int drbg_hash_df(struct drbg_state *drbg,
> + unsigned char *outval, size_t outlen,
> + struct drbg_string *entropy)
> +{
> + int ret = 0;
> + size_t len = 0;
> + unsigned char input[5];
> + unsigned char *tmp = drbg->scratchpad + drbg_statelen(drbg);
> + struct drbg_string data1;
> +
> + memset(tmp, 0, drbg_blocklen(drbg));
> +
> + /* 10.4.1 step 3 */
> + input[0] = 1;
> + drbg_int2byte(&input[1], (outlen * 8), 4);
> +
> + /* 10.4.1 step 4.1 -- concatenation of data for input into hash */
> + drbg_string_fill(&data1, input, 5);
> + data1.next = entropy;
> +
> + /* 10.4.1 step 4 */
> + while (len < outlen) {
> + short blocklen = 0;
> + /* 10.4.1 step 4.1 */
> + ret = drbg_kcapi_hash(drbg, NULL, tmp, &data1);
> + if (ret)
> + goto out;
> + /* 10.4.1 step 4.2 */
> + input[0]++;
> + blocklen = (drbg_blocklen(drbg) < (outlen - len)) ?
> + drbg_blocklen(drbg) : (outlen - len);
> + memcpy(outval + len, tmp, blocklen);
> + len += blocklen;
> + }
> +
> +out:
> + memset(tmp, 0, drbg_blocklen(drbg));
> + return ret;
> +}
> +
> +/* update function for Hash DRBG as defined in 10.1.1.2 / 10.1.1.3 */
> +static int drbg_hash_update(struct drbg_state *drbg, struct drbg_string *seed,
> + int reseed)
> +{
> + int ret = 0;
> + struct drbg_string data1, data2;
> + unsigned char *V = drbg->scratchpad;
> + unsigned char prefix = DRBG_PREFIX1;
> +
> + memset(drbg->scratchpad, 0, drbg_statelen(drbg));
> + if (!seed)
> + return -EINVAL;
> +
> + if (reseed) {
> + /* 10.1.1.3 step 1: string length is concatenation of
> + * 1 byte, V and seed (which is concatenated entropy/addtl
> + * input)
> + */
> + memcpy(V, drbg->V, drbg_statelen(drbg));
> + drbg_string_fill(&data1, &prefix, 1);
> + drbg_string_fill(&data2, V, drbg_statelen(drbg));
> + data1.next = &data2;
> + data2.next = seed;
> + } else {
> + drbg_string_fill(&data1, seed->buf, seed->len);
> + data1.next = seed->next;
> + }
> +
> + /* 10.1.1.2 / 10.1.1.3 step 2 and 3 */
> + ret = drbg_hash_df(drbg, drbg->V, drbg_statelen(drbg), &data1);
> + if (ret)
> + goto out;
> +
> + /* 10.1.1.2 / 10.1.1.3 step 4 -- concatenation */
> + prefix = DRBG_PREFIX0;
> + drbg_string_fill(&data1, &prefix, 1);
> + drbg_string_fill(&data2, drbg->V, drbg_statelen(drbg));
> + data1.next = &data2;
> + /* 10.1.1.2 / 10.1.1.3 step 4 -- df operation */
> + ret = drbg_hash_df(drbg, drbg->C, drbg_statelen(drbg), &data1);
> +
> +out:
> + memset(drbg->scratchpad, 0, drbg_statelen(drbg));
> + return ret;
> +}
> +
> +/* processing of additional information string for Hash DRBG */
> +static int drbg_hash_process_addtl(struct drbg_state *drbg,
> + struct drbg_string *addtl)
> +{
> + int ret = 0;
> + struct drbg_string data1, data2;
> + struct drbg_string *data3;
> + unsigned char prefix = DRBG_PREFIX2;
> +
> + /* this is value w as per documentation */
> + memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
> +
> + /* 10.1.1.4 step 2 */
> + if (!addtl || 0 == addtl->len)
> + return 0;
> +
> + /* 10.1.1.4 step 2a -- concatenation */
> + drbg_string_fill(&data1, &prefix, 1);
> + drbg_string_fill(&data2, drbg->V, drbg_statelen(drbg));
> + data3 = addtl;
> + data1.next = &data2;
> + data2.next = data3;
> + data3->next = NULL;
> + /* 10.1.1.4 step 2a -- cipher invocation */
> + ret = drbg_kcapi_hash(drbg, NULL, drbg->scratchpad, &data1);
> + if (ret)
> + goto out;
> +
> + /* 10.1.1.4 step 2b */
> + drbg_add_buf(drbg->V, drbg_statelen(drbg),
> + drbg->scratchpad, drbg_blocklen(drbg));
> +
> +out:
> + memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
> + return ret;
> +}
> +
> +/*
> + * Hashgen defined in 10.1.1.4
> + */
> +static int drbg_hash_hashgen(struct drbg_state *drbg,
> + unsigned char *buf,
> + unsigned int buflen)
> +{
> + int len = 0;
> + int ret = 0;
> + unsigned char *src = drbg->scratchpad;
> + unsigned char *dst = drbg->scratchpad + drbg_statelen(drbg);
> + struct drbg_string data;
> + unsigned char prefix = DRBG_PREFIX1;
> +
> + /* use the scratchpad as a lookaside buffer */
> + memset(src, 0, drbg_statelen(drbg));
> + memset(dst, 0, drbg_blocklen(drbg));
> +
> + /* 10.1.1.4 step hashgen 2 */
> + memcpy(src, drbg->V, drbg_statelen(drbg));
> +
> + drbg_string_fill(&data, src, drbg_statelen(drbg));
> + while (len < buflen) {
> + unsigned int outlen = 0;
> + /* 10.1.1.4 step hashgen 4.1 */
> + ret = drbg_kcapi_hash(drbg, NULL, dst, &data);
> + if (ret) {
> + len = ret;
> + goto out;
> + }
> + outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
> + drbg_blocklen(drbg) : (buflen - len);
> + if (!drbg_fips_continuous_test(drbg, dst)) {
> + drbg_add_buf(src, drbg_statelen(drbg), &prefix, 1);
> + continue;
> + }
> + /* 10.1.1.4 step hashgen 4.2 */
> + memcpy(buf + len, dst, outlen);
> + len += outlen;
> + /* 10.1.1.4 hashgen step 4.3 */
> + if (len < buflen)
> + drbg_add_buf(src, drbg_statelen(drbg), &prefix, 1);
> + }
> +
> +out:
> + memset(drbg->scratchpad, 0,
> + (drbg_statelen(drbg) + drbg_blocklen(drbg)));
> + return len;
> +}
> +
> +/* generate function for Hash DRBG as defined in 10.1.1.4 */
> +static int drbg_hash_generate(struct drbg_state *drbg,
> + unsigned char *buf, unsigned int buflen,
> + struct drbg_string *addtl)
> +{
> + int len = 0;
> + int ret = 0;
> + unsigned char req[8];
> + unsigned char prefix = DRBG_PREFIX3;
> + struct drbg_string data1, data2;
> +
> + /*
> + * scratchpad usage: drbg_hash_process_addtl uses the scratchpad, but
> + * fully completes before returning. Thus, we can reuse the scratchpad
> + */
> + /* 10.1.1.4 step 2 */
> + ret = drbg_hash_process_addtl(drbg, addtl);
> + if (ret)
> + return ret;
> + /* 10.1.1.4 step 3 -- invocation of the Hashgen function defined in
> + * 10.1.1.4 */
> + len = drbg_hash_hashgen(drbg, buf, buflen);
> +
> + /* this is the value H as documented in 10.1.1.4 */
> + memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
> + /* 10.1.1.4 step 4 */
> + drbg_string_fill(&data1, &prefix, 1);
> + drbg_string_fill(&data2, drbg->V, drbg_statelen(drbg));
> + data1.next = &data2;
> + ret = drbg_kcapi_hash(drbg, NULL, drbg->scratchpad, &data1);
> + if (ret) {
> + len = ret;
> + goto out;
> + }
> +
> + /* 10.1.1.4 step 5 */
> + drbg_add_buf(drbg->V, drbg_statelen(drbg),
> + drbg->scratchpad, drbg_blocklen(drbg));
> + drbg_add_buf(drbg->V, drbg_statelen(drbg),
> + drbg->C, drbg_statelen(drbg));
> + drbg_int2byte(req, drbg->reseed_ctr, sizeof(req));
> + drbg_add_buf(drbg->V, drbg_statelen(drbg), req, 8);
> +
> +out:
> + memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
> + return len;
> +}
> +
> +/*
> + * scratchpad usage: as update and generate are used isolated, both
> + * can use the scratchpad
> + */
> +static struct drbg_state_ops drbg_hash_ops = {
> + .update = drbg_hash_update,
> + .generate = drbg_hash_generate,
> + .crypto_init = drbg_init_hash_kernel,
> + .crypto_fini = drbg_fini_hash_kernel,
> +};
> +#endif /* CONFIG_CRYPTO_DRBG_HASH */
> +
> +/******************************************************************
> + * Functions common for DRBG implementations
> + ******************************************************************/
> +
> +/*
> + * Seeding or reseeding of the DRBG
> + *
> + * @drbg: DRBG state struct
> + * @pers: personalization / additional information buffer
> + * @reseed: 0 for initial seed process, 1 for reseeding
> + *
> + * return:
> + * 0 on success
> + * error value otherwise
> + */
> +static int drbg_seed(struct drbg_state *drbg, struct drbg_string *pers,
> + bool reseed)
> +{
> + int ret = 0;
> + unsigned char *entropy = NULL;
> + size_t entropylen = 0;
> + struct drbg_string data1;
> +
> + /* 9.1 / 9.2 / 9.3.1 step 3 */
> + if (pers && pers->len > (drbg_max_addtl(drbg))) {
> + pr_devel("DRBG: personalization string too long %lu\n",
> + pers->len);
> + return -EINVAL;
> + }
> +
> + if (drbg->test_data && drbg->test_data->testentropy) {
> + drbg_string_fill(&data1, drbg->test_data->testentropy->buf,
> + drbg->test_data->testentropy->len);
> + pr_devel("DRBG: using test entropy\n");
> + } else {
> + /* Gather entropy equal to the security strength of the DRBG.
> + * With a derivation function, a nonce is required in addition
> + * to the entropy. A nonce must be at least 1/2 of the security
> + * strength of the DRBG in size. Thus, entropy * nonce is 3/2
> + * of the strength. The consideration of a nonce is only
> + * applicable during initial seeding. */
> + entropylen = drbg_sec_strength(drbg->core->flags);
> + if (!entropylen)
> + return -EFAULT;
> + if (!reseed)
> + /* make sure we round up strength/2 in
> + * case it is not divisible by 2 */
> + entropylen = ((entropylen + 1) / 2) * 3;
> + pr_devel("DRBG: (re)seeding with %zu bytes of entropy\n",
> + entropylen);
> + entropy = kzalloc(entropylen, GFP_KERNEL);
> + if (!entropy)
> + return -ENOMEM;
> + get_random_bytes(entropy, entropylen);
> + drbg_string_fill(&data1, entropy, entropylen);
> + }
> +
> + /* concatenation of entropy with personalization str / addtl input)
> + * the variable pers is directly handed by the caller, check its
> + * contents whether it is appropriate */
> + if (pers && pers->buf && 0 < pers->len && NULL == pers->next) {
> + data1.next = pers;
> + pr_devel("DRBG: using personalization string\n");
> + }
> +
> + ret = drbg->d_ops->update(drbg, &data1, reseed);
> + if (ret)
> + goto out;
> +
> + drbg->seeded = true;
> + /* 10.1.1.2 / 10.1.1.3 step 5 */
> + drbg->reseed_ctr = 1;
> +
> +out:
> + if (entropy)
> + kzfree(entropy);
> + return ret;
> +}
> +
> +/*
> + * Free all substructures in a DRBG state without the DRBG state structure
> + */
> +static inline void drbg_dealloc_state(struct drbg_state *drbg)
> +{
> + if (!drbg)
> + return;
> + if (drbg->V)
> + kzfree(drbg->V);
> + drbg->V = NULL;
> + if (drbg->C)
> + kzfree(drbg->C);
> + drbg->C = NULL;
> + if (drbg->scratchpad)
> + kzfree(drbg->scratchpad);
> + drbg->scratchpad = NULL;
> + drbg->reseed_ctr = 0;
> +#ifdef CONFIG_CRYPTO_FIPS
> + if (drbg->prev)
> + kzfree(drbg->prev);
> + drbg->prev = NULL;
> + drbg->fips_primed = false;
> +#endif
> +}
> +
> +/*
> + * Allocate all sub-structures for a DRBG state
> + * The DRBG state structure must already be allocated
> + */
> +static inline int drbg_alloc_state(struct drbg_state *drbg)
> +{
> + int ret = -ENOMEM;
> + unsigned int sb_size = 0;
> +
> + if (!drbg)
> + return -EINVAL;
> +
> + drbg->V = kzalloc(drbg_statelen(drbg), GFP_KERNEL);
> + if (!drbg->V)
> + goto err;
> + drbg->C = kzalloc(drbg_statelen(drbg), GFP_KERNEL);
> + if (!drbg->C)
> + goto err;
> +#ifdef CONFIG_CRYPTO_FIPS
> + drbg->prev = kzalloc(drbg_blocklen(drbg), GFP_KERNEL);
> + if (!drbg->prev)
> + goto err;
> + drbg->fips_primed = false;
> +#endif
> + /* scratchpad is only generated for CTR and Hash */
> + if (drbg->core->flags & DRBG_HMAC)
> + sb_size = 0;
> + else if (drbg->core->flags & DRBG_CTR)
> + sb_size = drbg_statelen(drbg) + drbg_blocklen(drbg) + /* temp */
> + drbg_statelen(drbg) + /* df_data */
> + drbg_blocklen(drbg) + /* pad */
> + drbg_blocklen(drbg) + /* iv */
> + drbg_statelen(drbg); /* temp */
> + else
> + sb_size = drbg_statelen(drbg) + drbg_blocklen(drbg);
> +
> + if (0 < sb_size) {
> + drbg->scratchpad = kzalloc(sb_size, GFP_KERNEL);
> + if (!drbg->scratchpad)
> + goto err;
> + }
> + spin_lock_init(&drbg->drbg_lock);
> + return 0;
> +
> +err:
> + drbg_dealloc_state(drbg);
> + return ret;
> +}
> +
> +/*
> + * Strategy to avoid holding long term locks: generate a shadow copy of DRBG
> + * and perform all operations on this shadow copy. After finishing, restore
> + * the updated state of the shadow copy into original drbg state. This way,
> + * only the read and write operations of the original drbg state must be
> + * locked
> + */
> +
> +/*
> + * Copy the DRBG state
> + */
> +static inline void drbg_copy_drbg(struct drbg_state *src,
> + struct drbg_state *dst)
> +{
> + if (!src || !dst)
> + return;
> + memcpy(dst->V, src->V, drbg_statelen(src));
> + memcpy(dst->C, src->C, drbg_statelen(src));
> + dst->reseed_ctr = src->reseed_ctr;
> + /* no copy of scratchpad */
> + /* priv_data is initialized with call to crypto_init */
> + /* d_ops and core are set outside, as these parameters are const */
> + dst->seeded = src->seeded;
> + dst->pr = src->pr;
> +#ifdef CONFIG_CRYPTO_FIPS
> + dst->fips_primed = src->fips_primed;
> + memcpy(dst->prev, src->prev, drbg_blocklen(src));
> +#endif
> + /* test_data is set outside to prevent it being copied back */
> +}
> +/*
> + * Generate shadow copy of the DRBG state
> + */
> +static int drbg_make_shadow(struct drbg_state *drbg, struct drbg_state **shadow)
> +{
> + int ret = -ENOMEM;
> + struct drbg_state *tmp = NULL;
> +
> + /* some sanity checks */
> + if (!drbg || !drbg->core || !drbg->V || !drbg->C) {
> + pr_devel("DRBG: attempt to generate shadow copy for "
> + "uninitialized DRBG state rejected\n");
> + return -EINVAL;
> + }
> + /* HMAC does not have a scratchpad */
> + if (!(drbg->core->flags & DRBG_HMAC) && NULL == drbg->scratchpad)
> + return -EINVAL;
> +
> + tmp = kzalloc(sizeof(struct drbg_state), GFP_KERNEL);
> + if (!tmp)
> + return -ENOMEM;
> +
> + /* read-only data as they are defined as const, no lock needed */
> + tmp->core = drbg->core;
> + tmp->d_ops = drbg->d_ops;
> +
> + ret = drbg_alloc_state(tmp);
> + if (ret)
> + goto err;
> +
> + spin_lock_bh(&drbg->drbg_lock);
> + drbg_copy_drbg(drbg, tmp);
> + /* only make a link to the test buffer, as we only read that data */
> + tmp->test_data = drbg->test_data;
> + spin_unlock_bh(&drbg->drbg_lock);
> + *shadow = tmp;
> + return 0;
> +
> +err:
> + if (tmp)
> + kzfree(tmp);
> + return ret;
> +}
> +
> +/*
> + * Restore shadow state into original DRBG state
> + */
> +static void drbg_restore_shadow(struct drbg_state *drbg,
> + struct drbg_state **shadow)
> +{
> + struct drbg_state *tmp = *shadow;
> +
> + spin_lock_bh(&drbg->drbg_lock);
> + drbg_copy_drbg(tmp, drbg);
> + spin_unlock_bh(&drbg->drbg_lock);
> + drbg_dealloc_state(tmp);
> + kzfree(tmp);
> + *shadow = NULL;
> +}
> +
> +/*************************************************************************
> + * DRBG interface functions
> + *************************************************************************/
> +
> +/*
> + * DRBG generate function as required by SP800-90A - this function
> + * generates random numbers
> + *
> + * @drbg DRBG state handle
> + * @buf Buffer where to store the random numbers -- the buffer must already
> + * be pre-allocated by caller
> + * @buflen Length of output buffer - this value defines the number of random
> + * bytes pulled from DRBG
> + * @addtl Additional input that is mixed into state, may be NULL -- note
> + * the entropy is pulled by the DRBG internally unconditionally
> + * as defined in SP800-90A. The additional input is mixed into
> + * the state in addition to the pulled entropy.
> + *
> + * return: generated number of bytes
> + */
> +static int drbg_generate(struct drbg_state *drbg,
> + unsigned char *buf, unsigned int buflen,
> + struct drbg_string *addtl)
> +{
> + int len = 0;
> + struct drbg_state *shadow = NULL;
> +
> + if (0 == buflen || !buf) {
> + pr_devel("DRBG: no output buffer provided\n");
> + return -EINVAL;
> + }
> + if (addtl && NULL == addtl->buf && 0 < addtl->len) {
> + pr_devel("DRBG: wrong format of additional information\n");
> + return -EINVAL;
> + }
> +
> + len = drbg_make_shadow(drbg, &shadow);
> + if (len) {
> + pr_devel("DRBG: shadow copy cannot be generated\n");
> + return len;
> + }
> + /* 9.3.1 step 2 */
> + len = -EINVAL;
> + if (buflen > (drbg_max_request_bytes(shadow))) {
> + pr_devel("DRBG: requested random numbers too large %u\n",
> + buflen);
> + goto err;
> + }
> + /* 9.3.1 step 3 is implicit with the chosen DRBG */
> + /* 9.3.1 step 4 */
> + if (addtl && addtl->len > (drbg_max_addtl(shadow))) {
> + pr_devel("DRBG: additional information string too long %zu\n",
> + addtl->len);
> + goto err;
> + }
> + /* 9.3.1 step 5 is implicit with the chosen DRBG */
> + /* 9.3.1 step 6 and 9 supplemented by 9.3.2 step c -- the spec is a
> + * bit convoluted here, we make it simpler */
> + if ((drbg_max_requests(shadow)) < shadow->reseed_ctr)
> + shadow->seeded = false;
> +
> + /* allocate cipher handle */
> + if (shadow->d_ops->crypto_init) {
> + len = shadow->d_ops->crypto_init(shadow);
> + if (len)
> + goto err;
> + }
> +
> + if (shadow->pr || !shadow->seeded) {
> + pr_devel("DRBG: reseeding before generation (prediction "
> + "resistance: %s, state %s)\n",
> + drbg->pr ? "true" : "false",
> + drbg->seeded ? "seeded" : "unseeded");
> + /* 9.3.1 steps 7.1 through 7.3 */
> + len = drbg_seed(shadow, addtl, true);
> + if (len)
> + goto err;
> + /* 9.3.1 step 7.4 */
> + addtl = NULL;
> + }
> + /* 9.3.1 step 8 and 10 */
> + len = shadow->d_ops->generate(shadow, buf, buflen, addtl);
> +
> + /* 10.1.1.4 step 6, 10.1.2.5 step 7, 10.2.1.5.2 step 7 */
> + shadow->reseed_ctr++;
> + if (0 >= len)
> + goto err;
> +
> + /* 11.3.3 -- re-perform self tests after some generated random
> + * numbers, the chosen value after which self test is performed
> + * is arbitrary, but it should be reasonable */
> + /* Here we do not perform the self tests because of the following
> + * reasons: it is mathematically impossible that the initial self tests
> + * were successfully and the following are not. If the initial would
> + * pass and the following would not, the kernel integrity is violated.
> + * In this case, the entire kernel operation is questionable and it
> + * is unlikely that the integrity violation only affects to the
> + * correct operation of the DRBG.
> + */
> +#if 0
> + if (shadow->reseed_ctr && !(shadow->reseed_ctr % 4096)) {
> + int err = 0;
> + pr_devel("DRBG: start to perform self test\n");
> + if (drbg->core->flags & DRBG_HMAC)
> + err = alg_test("drbg(pr(hmac(sha256)))",
> + "drbg(pr(hmac(sha256)))", 0, 0);
> + else if (drbg->core->flags & DRBG_CTR)
> + err = alg_test("drbg(pr(ctr(aes128)))",
> + "drbg(pr(ctr(aes128)))", 0, 0);
> + else
> + err = alg_test("drbg(pr(sha256))",
> + "drbg(pr(sha256))", 0, 0);
> + if (err) {
> + pr_err("DRBG: periodical self test failed\n");
> + /* uninstantiate implies that from now on, only errors
> + * are returned when reusing this DRBG cipher handle */
> + drbg_uninstantiate(drbg);
> + drbg_dealloc_state(shadow);
> + kzfree(shadow);
> + return 0;
> + } else {
> + pr_devel("DRBG: self test successful\n");
> + }
> + }
> +#endif
> +
> +err:
> + if (shadow->d_ops->crypto_fini)
> + shadow->d_ops->crypto_fini(shadow);
> + drbg_restore_shadow(drbg, &shadow);
> + return len;
> +}
> +
> +/*
> + * Wrapper around drbg_generate which can pull arbitrary long strings
> + * from the DRBG without hitting the maximum request limitation.
> + *
> + * Parameters: see drbg_generate
> + * Return codes: see drbg_generate -- if one drbg_generate request fails,
> + * the entire drbg_generate_long request fails
> + */
> +static int drbg_generate_long(struct drbg_state *drbg,
> + unsigned char *buf, unsigned int buflen,
> + struct drbg_string *addtl)
> +{
> + int len = 0;
> + unsigned int slice = 0;
> + do {
> + int tmplen = 0;
> + unsigned int chunk = 0;
> + slice = ((buflen - len) / drbg_max_request_bytes(drbg));
> + chunk = slice ? drbg_max_request_bytes(drbg) : (buflen - len);
> + tmplen = drbg_generate(drbg, buf + len, chunk, addtl);
> + if (0 >= tmplen)
> + return tmplen;
> + len += tmplen;
> + } while (slice > 0);
> + return len;
> +}
> +
> +/*
> + * DRBG instantiation function as required by SP800-90A - this function
> + * sets up the DRBG handle, performs the initial seeding and all sanity
> + * checks required by SP800-90A
> + *
> + * @drbg memory of state -- if NULL, new memory is allocated
> + * @pers Personalization string that is mixed into state, may be NULL -- note
> + * the entropy is pulled by the DRBG internally unconditionally
> + * as defined in SP800-90A. The additional input is mixed into
> + * the state in addition to the pulled entropy.
> + * @coreref reference to core
> + * @pr prediction resistance enabled
> + *
> + * return
> + * 0 on success
> + * error value otherwise
> + */
> +static int drbg_instantiate(struct drbg_state *drbg, struct drbg_string *pers,
> + int coreref, bool pr)
> +{
> + int ret = -ENOMEM;
> +
> + pr_devel("DRBG: Initializing DRBG core %d with prediction resistance "
> + "%s\n", coreref, pr ? "enabled" : "disabled");
> + drbg->core = &drbg_cores[coreref];
> + drbg->pr = pr;
> + drbg->seeded = false;
> + switch (drbg->core->flags & DRBG_TYPE_MASK) {
> +#ifdef CONFIG_CRYPTO_DRBG_HMAC
> + case DRBG_HMAC:
> + drbg->d_ops = &drbg_hmac_ops;
> + break;
> +#endif /* CONFIG_CRYPTO_DRBG_HMAC */
> +#ifdef CONFIG_CRYPTO_DRBG_HASH
> + case DRBG_HASH:
> + drbg->d_ops = &drbg_hash_ops;
> + break;
> +#endif /* CONFIG_CRYPTO_DRBG_HASH */
> +#ifdef CONFIG_CRYPTO_DRBG_CTR
> + case DRBG_CTR:
> + drbg->d_ops = &drbg_ctr_ops;
> + break;
> +#endif /* CONFIG_CRYPTO_DRBG_CTR */
> + default:
> + return -EOPNOTSUPP;
> + }
> +
> + /* 9.1 step 1 is implicit with the selected DRBG type -- see
> + * drbg_sec_strength() */
> +
> + /* 9.1 step 2 is implicit as caller can select prediction resistance
> + * and the flag is copied into drbg->flags --
> + * all DRBG types support prediction resistance */
> +
> + /* 9.1 step 4 is implicit in drbg_sec_strength */
> +
> + /* no allocation of drbg as this is done by the kernel crypto API */
> + ret = drbg_alloc_state(drbg);
> + if (ret)
> + return ret;
> +
> + ret = -EFAULT;
> + /* allocate cipher handle */
> + if (drbg->d_ops->crypto_init && drbg->d_ops->crypto_init(drbg))
> + goto err;
> + /* 9.1 step 6 through 11 */
> + ret = drbg_seed(drbg, pers, false);
> + /* deallocate cipher handle */
> + if (drbg->d_ops->crypto_fini)
> + drbg->d_ops->crypto_fini(drbg);
> + if (ret)
> + goto err;
> +
> + return 0;
> +
> +err:
> + drbg_dealloc_state(drbg);
> + return ret;
> +}
> +
> +/*
> + * DRBG uninstantiate function as required by SP800-90A - this function
> + * frees all buffers and the DRBG handle
> + *
> + * @drbg DRBG state handle
> + *
> + * return
> + * 0 on success
> + */
> +static int drbg_uninstantiate(struct drbg_state *drbg)
> +{
> + spin_lock_bh(&drbg->drbg_lock);
> + drbg_dealloc_state(drbg);
> + /* no scrubbing of test_data -- this shall survive an uninstantiate */
> + spin_unlock_bh(&drbg->drbg_lock);
> + /* no freeing of drbg as this is done by the kernel crypto API */
> + return 0;
> +}
> +
> +/*
> + * Helper function for setting the test data in the DRBG
> + *
> + * @drbg DRBG state handle
> + * @test_data test data to sets
> + */
> +static inline void drbg_set_testdata(struct drbg_state *drbg,
> + struct drbg_test_data *test_data)
> +{
> + if (!test_data || !test_data->testentropy)
> + return;
> + spin_lock_bh(&drbg->drbg_lock);
> + drbg->test_data = test_data;
> + spin_unlock_bh(&drbg->drbg_lock);
> +}
> +
> +/***************************************************************
> + * Kernel crypto APi cipher invocations requested by DRBG
> + ***************************************************************/
> +
> +#if defined(CONFIG_CRYPTO_DRBG_HASH) || defined(CONFIG_CRYPTO_DRBG_HMAC)
> +struct sdesc {
> + struct shash_desc shash;
> + char ctx[];
> +};
> +
> +static int drbg_init_hash_kernel(struct drbg_state *drbg)
> +{
> + struct sdesc *sdesc;
> + struct crypto_shash *tfm;
> +
> + tfm = crypto_alloc_shash(drbg->core->backend_cra_name, 0, 0);
> + if (IS_ERR(tfm)) {
> + pr_info("DRBG: could not allocate digest TFM handle\n");
> + return PTR_ERR(tfm);
> + }
> + BUG_ON(drbg_blocklen(drbg) != crypto_shash_digestsize(tfm));
> + sdesc = kzalloc(sizeof(struct shash_desc) + crypto_shash_descsize(tfm),
> + GFP_KERNEL);
> + if (!sdesc) {
> + crypto_free_shash(tfm);
> + return -ENOMEM;
> + }
> +
> + sdesc->shash.tfm = tfm;
> + sdesc->shash.flags = 0;
> + drbg->priv_data = sdesc;
> + return 0;
> +}
> +
> +static int drbg_fini_hash_kernel(struct drbg_state *drbg)
> +{
> + struct sdesc *sdesc = (struct sdesc *)drbg->priv_data;
> + if (sdesc) {
> + crypto_free_shash(sdesc->shash.tfm);
> + kzfree(sdesc);
> + }
> + drbg->priv_data = NULL;
> + return 0;
> +}
> +
> +static int drbg_kcapi_hash(struct drbg_state *drbg, const unsigned char *key,
> + unsigned char *outval, const struct drbg_string *in)
> +{
> + struct sdesc *sdesc = (struct sdesc *)drbg->priv_data;
> +
> + if (key)
> + crypto_shash_setkey(sdesc->shash.tfm, key, drbg_statelen(drbg));
> + crypto_shash_init(&sdesc->shash);
> + for (; NULL != in; in = in->next)
> + crypto_shash_update(&sdesc->shash, in->buf, in->len);
> + return crypto_shash_final(&sdesc->shash, outval);
> +}
> +#endif /* (CONFIG_CRYPTO_DRBG_HASH || CONFIG_CRYPTO_DRBG_HMAC) */
> +
> +#ifdef CONFIG_CRYPTO_DRBG_CTR
> +static int drbg_init_sym_kernel(struct drbg_state *drbg)
> +{
> + int ret = 0;
> + struct crypto_blkcipher *tfm;
> +
> + tfm = crypto_alloc_blkcipher(drbg->core->backend_cra_name, 0, 0);
> + if (IS_ERR(tfm)) {
> + pr_info("DRBG: could not allocate cipher TFM handle\n");
> + return PTR_ERR(tfm);
> + }
> + BUG_ON(drbg_blocklen(drbg) != crypto_blkcipher_blocksize(tfm));
> + drbg->priv_data = tfm;
> + return ret;
> +}
> +
> +static int drbg_fini_sym_kernel(struct drbg_state *drbg)
> +{
> + struct crypto_blkcipher *tfm =
> + (struct crypto_blkcipher *)drbg->priv_data;
> + if (tfm)
> + crypto_free_blkcipher(tfm);
> + drbg->priv_data = NULL;
> + return 0;
> +}
> +
> +static int drbg_kcapi_sym(struct drbg_state *drbg, const unsigned char *key,
> + unsigned char *outval, const struct drbg_string *in)
> +{
> + int ret = 0;
> + struct scatterlist sg_in, sg_out;
> + struct blkcipher_desc desc;
> + struct crypto_blkcipher *tfm =
> + (struct crypto_blkcipher *)drbg->priv_data;
> +
> + desc.tfm = tfm;
> + desc.flags = 0;
> + crypto_blkcipher_setkey(tfm, key, (drbg_keylen(drbg)));
> + /* in is only component */
> + sg_init_one(&sg_in, in->buf, in->len);
> + sg_init_one(&sg_out, outval, drbg_blocklen(drbg));
> + ret = crypto_blkcipher_encrypt(&desc, &sg_out, &sg_in, in->len);
> +
> + return ret;
> +}
> +#endif /* CONFIG_CRYPTO_DRBG_CTR */
> +
> +/***************************************************************
> + * Kernel crypto API interface to register DRBG
> + ***************************************************************/
> +
> +/*
> + * Look up the DRBG flags by given kernel crypto API cra_name
> + * The code uses the drbg_cores definition to do this
> + *
> + * @cra_name kernel crypto API cra_name
> + * @coreref reference to integer which is filled with the pointer to
> + * the applicable core
> + * @pr reference for setting prediction resistance
> + *
> + * return: flags
> + */
> +static inline void drbg_convert_tfm_core(const char *cra_name,
> + int *coreref, bool *pr)
> +{
> + int i = 0;
> + size_t start = 0;
> + int len = 0;
> +
> + *pr = true;
> + /* disassemble the names */
> + if (0 == memcmp(cra_name, "drbg(nopr(", 10)) {
> + start = 10;
> + *pr = false;
> + } else if (0 == memcmp(cra_name, "drbg(pr(", 8)) {
> + start = 8;
> + } else {
> + return;
> + }
> +
> + /* remove the first part and the closing parenthesis */
> + len = strlen(cra_name) - start - 2;
> + for (i = 0; ARRAY_SIZE(drbg_cores) > i; i++) {
> + if (0 == memcmp(cra_name + start,
> + drbg_cores[i].cra_name, len)) {
> + *coreref = i;
> + return;
> + }
> + }
> +}
> +
> +/*
> + * Initialize one DRBG invoked by the kernel crypto API
> + *
> + * Function uses the kernel crypto API cra_name to look up
> + * the flags to instantiate the DRBG
> + */
> +static int drbg_kcapi_init(struct crypto_tfm *tfm)
> +{
> + struct drbg_state *drbg = crypto_tfm_ctx(tfm);
> + bool pr = false;
> + int coreref = 0;
> +
> + drbg_convert_tfm_core(crypto_tfm_alg_name(tfm), &coreref, &pr);
> + /* when personalization string is needed, the caller must call reset
> + * and provide the personalization string as seed information */
> + return drbg_instantiate(drbg, NULL, coreref, pr);
> +}
> +
> +static void drbg_kcapi_cleanup(struct crypto_tfm *tfm)
> +{
> + drbg_uninstantiate(crypto_tfm_ctx(tfm));
> +}
> +
> +/*
> + * Generate random numbers invoked by the kernel crypto API:
> + * The API of the kernel crypto API is extended as follows:
> + *
> + * If dlen is larger than zero, rdata is interpreted as the output buffer
> + * where random data is to be stored.
> + *
> + * If dlen is zero, rdata is interpreted as a pointer to a struct drbg_gen
> + * which holds the additional information string that is used for the
> + * DRBG generation process. The output buffer that is to be used to store
> + * data is also pointed to by struct drbg_gen.
> + *
> + */
> +static int drbg_kcapi_random(struct crypto_rng *tfm, u8 *rdata,
> + unsigned int dlen)
> +{
> + struct drbg_state *drbg = crypto_rng_ctx(tfm);
> + if (0 < dlen) {
> + return drbg_generate_long(drbg, rdata, dlen, NULL);
> + } else {
> + struct drbg_gen *data = (struct drbg_gen *)rdata;
> + /* catch NULL pointer */
> + if (!data)
> + return 0;
> + drbg_set_testdata(drbg, data->test_data);
> + return drbg_generate_long(drbg, data->outbuf, data->outlen,
> + data->addtl);
> + }
> +}
> +
> +/*
> + * Reset the DRBG invoked by the kernel crypto API
> + * The reset implies a full re-initialization of the DRBG. Similar to the
> + * generate function of drbg_kcapi_random, this function extends the
> + * kernel crypto API interface with struct drbg_gen
> + */
> +static int drbg_kcapi_reset(struct crypto_rng *tfm, u8 *seed, unsigned int slen)
> +{
> + struct drbg_state *drbg = crypto_rng_ctx(tfm);
> + struct crypto_tfm *tfm_base = crypto_rng_tfm(tfm);
> + bool pr = false;
> + struct drbg_string seed_string;
> + int coreref = 0;
> +
> + drbg_uninstantiate(drbg);
> + drbg_convert_tfm_core(crypto_tfm_alg_name(tfm_base), &coreref, &pr);
> + if (0 < slen) {
> + drbg_string_fill(&seed_string, seed, slen);
> + return drbg_instantiate(drbg, &seed_string, coreref, pr);
> + } else {
> + struct drbg_gen *data = (struct drbg_gen *)seed;
> + /* allow invocation of API call with NULL, 0 */
> + if (!data)
> + return drbg_instantiate(drbg, NULL, coreref, pr);
> + drbg_set_testdata(drbg, data->test_data);
> + return drbg_instantiate(drbg, data->addtl, coreref, pr);
> + }
> +}
> +
> +/***************************************************************
> + * Kernel module: code to load the module
> + ***************************************************************/
> +
> +/*
> + * Tests as defined in 11.3.2 in addition to the cipher tests: testing
> + * of the error handling.
> + *
> + * Note, testing of failing seed source as defined in 11.3.2 is not applicable
> + * as seed source of get_random_bytes does not fail.
> + * Note, testing the reseed counter is not done as an automatic reseeding
> + * is performed in drbg_generate when the reseed counter is too large.
> + */
> +static inline int __init drbg_healthcheck_sanity(void)
> +{
> +#ifdef CONFIG_CRYPTO_FIPS
> + unsigned int len = 0;
> +#define OUTBUFLEN 16
> + unsigned char buf[OUTBUFLEN];
> + struct drbg_state *drbg = NULL;
> + int ret = -EFAULT;
> + int rc = -EFAULT;
> + bool pr = false;
> + int coreref = 0;
> + struct drbg_string addtl;
> + size_t max_addtllen, max_request_bytes;
> +
> + /* only perform test in FIPS mode */
> + if (0 == fips_enabled)
> + return 0;
> +
> +#ifdef CONFIG_CRYPTO_DRBG_CTR
> + drbg_convert_tfm_core("drbg(nopr(ctr(aes128)))", &coreref, &pr);
> +#elif CONFIG_CRYPTO_DRBG_HASH
> + drbg_convert_tfm_core("drbg(nopr(sha256)", &coreref, &pr);
> +#else
> + drbg_convert_tfm_core("drbg(nopr(hmac(sha256)))", &coreref, &pr);
> +#endif
> +
> + drbg = kzalloc(sizeof(struct drbg_state), GFP_KERNEL);
> + if (!drbg)
> + return -ENOMEM;
> +
> + /* if the following tests fail, it is likely that there is a buffer
> + * overflow as buf is much smaller than the requested or provided
> + * string lengths -- in case the error handling does not succeed
> + * we may get an OOPS. And we want to get an OOPS as this is a
> + * grave bug */
> +
> + /* get a valid instance of DRBG for following tests */
> + ret = drbg_instantiate(drbg, NULL, coreref, pr);
> + if (ret) {
> + rc = ret;
> + goto outbuf;
> + }
> + max_addtllen = drbg_max_addtl(drbg);
> + max_request_bytes = drbg_max_request_bytes(drbg);
> + drbg_string_fill(&addtl, buf, max_addtllen + 1);
> + /* overflow addtllen with additonal info string */
> + len = drbg_generate(drbg, buf, OUTBUFLEN, &addtl);
> + BUG_ON(0 < len);
> + /* overflow max_bits */
> + len = drbg_generate(drbg, buf, (max_request_bytes + 1), NULL);
> + BUG_ON(0 < len);
> + drbg_uninstantiate(drbg);
> +
> + /* overflow max addtllen with personalization string */
> + ret = drbg_instantiate(drbg, &addtl, coreref, pr);
> + BUG_ON(0 == ret);
> + /* test uninstantated DRBG */
> + len = drbg_generate(drbg, buf, (max_request_bytes + 1), NULL);
> + BUG_ON(0 < len);
> + /* all tests passed */
> + rc = 0;
> +
> + pr_devel("DRBG: Sanity tests for failure code paths successfully "
> + "completed\n");
> +
> + drbg_uninstantiate(drbg);
> +outbuf:
> + kzfree(drbg);
> + return rc;
> +#else /* CONFIG_CRYPTO_FIPS */
> + return 0;
> +#endif /* CONFIG_CRYPTO_FIPS */
> +}
> +
> +
> +static struct crypto_alg drbg_algs[22];
> +
> +/*
> + * Fill the array drbg_algs used to register the different DRBGs
> + * with the kernel crypto API. To fill the array, the information
> + * from drbg_cores[] is used.
> + */
> +static inline void __init drbg_fill_array(unsigned long i, unsigned long j,
> + int pr)
> +{
> + int pos = 0;
> +
> + memset(&drbg_algs[i], 0, sizeof(struct crypto_alg));
> + if (pr) {
> + memcpy(drbg_algs[i].cra_name, "drbg(pr(", 8);
> + memcpy(drbg_algs[i].cra_driver_name, "drbg_pr_", 8);
> + pos = 8;
> + } else {
> + memcpy(drbg_algs[i].cra_name, "drbg(nopr(", 10);
> + memcpy(drbg_algs[i].cra_driver_name, "drbg_nopr_", 10);
> + pos = 10;
> + }
> + memcpy(drbg_algs[i].cra_name + pos, drbg_cores[j].cra_name,
> + strlen(drbg_cores[j].cra_name));
> + memcpy(drbg_algs[i].cra_name + pos + strlen(drbg_cores[j].cra_name),
> + "))", 2);
> + memcpy(drbg_algs[i].cra_driver_name + pos,
> + drbg_cores[j].cra_driver_name,
> + strlen(drbg_cores[j].cra_driver_name));
> + drbg_algs[i].cra_priority = 100;
> + drbg_algs[i].cra_flags = CRYPTO_ALG_TYPE_RNG;
> + drbg_algs[i].cra_ctxsize = sizeof(struct drbg_state);
> + drbg_algs[i].cra_type = &crypto_rng_type;
> + drbg_algs[i].cra_module = THIS_MODULE;
> + drbg_algs[i].cra_init = drbg_kcapi_init;
> + drbg_algs[i].cra_exit = drbg_kcapi_cleanup;
> + drbg_algs[i].cra_u.rng.rng_make_random = drbg_kcapi_random;
> + drbg_algs[i].cra_u.rng.rng_reset = drbg_kcapi_reset;
> + drbg_algs[i].cra_u.rng.seedsize = 0;
> +}
> +
> +static int __init drbg_init(void)
> +{
> + unsigned int i = 0; /* pointer to drbg_algs */
> + unsigned int j = 0; /* pointer to drbg_cores */
> + int ret = -EFAULT;
> +
> + ret = drbg_healthcheck_sanity();
> + if (ret)
> + return ret;
> +
> + if (ARRAY_SIZE(drbg_cores) * 2 > ARRAY_SIZE(drbg_algs)) {
> + pr_info("DRBG: Cannot register all DRBG types"
> + "(slots needed: %lu, slots available: %lu)\n",
> + ARRAY_SIZE(drbg_cores) * 2, ARRAY_SIZE(drbg_algs));
> + return ret;
> + }
> +
> + /* each DRBG definition can be used with PR and without PR, thus
> + * we instantiate each DRBG in drbg_cores[] twice */
> + for (j = 0; ARRAY_SIZE(drbg_cores) > j; j++) {
> + drbg_fill_array(i, j, 1);
> + i++;
> + drbg_fill_array(i, j, 0);
> + i++;
> + }
> + return crypto_register_algs(drbg_algs, (ARRAY_SIZE(drbg_cores) * 2));
> +}
> +
> +void __exit drbg_exit(void)
> +{
> + crypto_unregister_algs(drbg_algs, (ARRAY_SIZE(drbg_cores) * 2));
> +}
> +
> +module_init(drbg_init);
> +module_exit(drbg_exit);
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Stephan Mueller <smueller@chronox.de>");
> +MODULE_DESCRIPTION("NIST SP800-90A Deterministic Random Bit Generator (DRBG) using following cores:"
> +#ifdef CONFIG_CRYPTO_DRBG_HMAC
> +"HMAC "
> +#endif
> +#ifdef CONFIG_CRYPTO_DRBG_HASH
> +"Hash "
> +#endif
> +#ifdef CONFIG_CRYPTO_DRBG_CTR
> +"CTR"
> +#endif
> +);
>
^ permalink raw reply [flat|nested] 29+ messages in thread