* [Patch v3 4/7] KEYS: trusted: Add generic trusted keys framework
2019-10-31 13:58 [Patch v3 0/7] Introduce TEE based Trusted Keys support Sumit Garg
` (2 preceding siblings ...)
2019-10-31 13:58 ` [Patch v3 3/7] tee: add private login method for kernel clients Sumit Garg
@ 2019-10-31 13:58 ` Sumit Garg
2019-10-31 13:58 ` [Patch v3 5/7] KEYS: trusted: Introduce TEE based Trusted Keys Sumit Garg
` (2 subsequent siblings)
6 siblings, 0 replies; 13+ messages in thread
From: Sumit Garg @ 2019-10-31 13:58 UTC (permalink / raw)
To: jens.wiklander, jarkko.sakkinen, dhowells
Cc: corbet, jejb, zohar, jmorris, serge, casey, ard.biesheuvel,
daniel.thompson, stuart.yoder, janne.karhunen, keyrings,
linux-integrity, linux-security-module, linux-doc, linux-kernel,
linux-arm-kernel, tee-dev, Sumit Garg
Current trusted keys framework is tightly coupled to use TPM device as
an underlying implementation which makes it difficult for implementations
like Trusted Execution Environment (TEE) etc. to provide trusked keys
support in case platform doesn't posses a TPM device.
So this patch tries to add generic trusted keys framework where underlying
implemtations like TPM, TEE etc. could be easily plugged-in.
Suggested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
---
include/keys/trusted-type.h | 45 ++++
include/keys/trusted_tpm.h | 15 --
security/keys/trusted-keys/Makefile | 1 +
security/keys/trusted-keys/trusted_common.c | 343 +++++++++++++++++++++++++++
security/keys/trusted-keys/trusted_tpm1.c | 345 +++++-----------------------
5 files changed, 447 insertions(+), 302 deletions(-)
create mode 100644 security/keys/trusted-keys/trusted_common.c
diff --git a/include/keys/trusted-type.h b/include/keys/trusted-type.h
index a94c03a..5559010 100644
--- a/include/keys/trusted-type.h
+++ b/include/keys/trusted-type.h
@@ -40,6 +40,51 @@ struct trusted_key_options {
uint32_t policyhandle;
};
+struct trusted_key_ops {
+ /*
+ * flag to indicate if trusted key implementation supports migration
+ * or not.
+ */
+ unsigned char migratable;
+
+ /* trusted key init */
+ int (*init)(void);
+
+ /* seal a trusted key */
+ int (*seal)(struct trusted_key_payload *p, char *datablob);
+
+ /* unseal a trusted key */
+ int (*unseal)(struct trusted_key_payload *p, char *datablob);
+
+ /* get random trusted key */
+ int (*get_random)(unsigned char *key, size_t key_len);
+
+ /* trusted key cleanup */
+ void (*cleanup)(void);
+};
+
extern struct key_type key_type_trusted;
+#if defined(CONFIG_TCG_TPM)
+extern struct trusted_key_ops tpm_trusted_key_ops;
+#endif
+
+#define TRUSTED_DEBUG 0
+
+#if TRUSTED_DEBUG
+static inline void dump_payload(struct trusted_key_payload *p)
+{
+ pr_info("trusted_key: key_len %d\n", p->key_len);
+ print_hex_dump(KERN_INFO, "key ", DUMP_PREFIX_NONE,
+ 16, 1, p->key, p->key_len, 0);
+ pr_info("trusted_key: bloblen %d\n", p->blob_len);
+ print_hex_dump(KERN_INFO, "blob ", DUMP_PREFIX_NONE,
+ 16, 1, p->blob, p->blob_len, 0);
+ pr_info("trusted_key: migratable %d\n", p->migratable);
+}
+#else
+static inline void dump_payload(struct trusted_key_payload *p)
+{
+}
+#endif
#endif /* _KEYS_TRUSTED_TYPE_H */
diff --git a/include/keys/trusted_tpm.h b/include/keys/trusted_tpm.h
index a56d8e1..5753231 100644
--- a/include/keys/trusted_tpm.h
+++ b/include/keys/trusted_tpm.h
@@ -60,17 +60,6 @@ static inline void dump_options(struct trusted_key_options *o)
16, 1, o->pcrinfo, o->pcrinfo_len, 0);
}
-static inline void dump_payload(struct trusted_key_payload *p)
-{
- pr_info("trusted_key: key_len %d\n", p->key_len);
- print_hex_dump(KERN_INFO, "key ", DUMP_PREFIX_NONE,
- 16, 1, p->key, p->key_len, 0);
- pr_info("trusted_key: bloblen %d\n", p->blob_len);
- print_hex_dump(KERN_INFO, "blob ", DUMP_PREFIX_NONE,
- 16, 1, p->blob, p->blob_len, 0);
- pr_info("trusted_key: migratable %d\n", p->migratable);
-}
-
static inline void dump_sess(struct osapsess *s)
{
print_hex_dump(KERN_INFO, "trusted-key: handle ", DUMP_PREFIX_NONE,
@@ -96,10 +85,6 @@ static inline void dump_options(struct trusted_key_options *o)
{
}
-static inline void dump_payload(struct trusted_key_payload *p)
-{
-}
-
static inline void dump_sess(struct osapsess *s)
{
}
diff --git a/security/keys/trusted-keys/Makefile b/security/keys/trusted-keys/Makefile
index 7b73ceb..2b1085b 100644
--- a/security/keys/trusted-keys/Makefile
+++ b/security/keys/trusted-keys/Makefile
@@ -4,5 +4,6 @@
#
obj-$(CONFIG_TRUSTED_KEYS) += trusted.o
+trusted-y += trusted_common.o
trusted-y += trusted_tpm1.o
trusted-y += trusted_tpm2.o
diff --git a/security/keys/trusted-keys/trusted_common.c b/security/keys/trusted-keys/trusted_common.c
new file mode 100644
index 0000000..8f00fde
--- /dev/null
+++ b/security/keys/trusted-keys/trusted_common.c
@@ -0,0 +1,343 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2010 IBM Corporation
+ * Copyright (c) 2019, Linaro Limited
+ *
+ * Author:
+ * David Safford <safford@us.ibm.com>
+ * Added generic trusted key framework: Sumit Garg <sumit.garg@linaro.org>
+ *
+ * See Documentation/security/keys/trusted-encrypted.rst
+ */
+
+#include <keys/user-type.h>
+#include <keys/trusted-type.h>
+#include <linux/capability.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/key-type.h>
+#include <linux/module.h>
+#include <linux/parser.h>
+#include <linux/rcupdate.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/uaccess.h>
+
+static struct trusted_key_ops *available_tk_ops[] = {
+#if defined(CONFIG_TCG_TPM)
+ &tpm_trusted_key_ops,
+#endif
+};
+static struct trusted_key_ops *tk_ops;
+
+enum {
+ Opt_err,
+ Opt_new, Opt_load, Opt_update,
+};
+
+static const match_table_t key_tokens = {
+ {Opt_new, "new"},
+ {Opt_load, "load"},
+ {Opt_update, "update"},
+ {Opt_err, NULL}
+};
+
+/*
+ * datablob_parse - parse the keyctl data and fill in the
+ * payload structure
+ *
+ * On success returns 0, otherwise -EINVAL.
+ */
+static int datablob_parse(char *datablob, struct trusted_key_payload *p)
+{
+ substring_t args[MAX_OPT_ARGS];
+ long keylen;
+ int ret = -EINVAL;
+ int key_cmd;
+ char *c;
+
+ /* main command */
+ c = strsep(&datablob, " \t");
+ if (!c)
+ return -EINVAL;
+ key_cmd = match_token(c, key_tokens, args);
+ switch (key_cmd) {
+ case Opt_new:
+ /* first argument is key size */
+ c = strsep(&datablob, " \t");
+ if (!c)
+ return -EINVAL;
+ ret = kstrtol(c, 10, &keylen);
+ if (ret < 0 || keylen < MIN_KEY_SIZE || keylen > MAX_KEY_SIZE)
+ return -EINVAL;
+ p->key_len = keylen;
+ ret = Opt_new;
+ break;
+ case Opt_load:
+ /* first argument is sealed blob */
+ c = strsep(&datablob, " \t");
+ if (!c)
+ return -EINVAL;
+ p->blob_len = strlen(c) / 2;
+ if (p->blob_len > MAX_BLOB_SIZE)
+ return -EINVAL;
+ ret = hex2bin(p->blob, c, p->blob_len);
+ if (ret < 0)
+ return -EINVAL;
+ ret = Opt_load;
+ break;
+ case Opt_update:
+ ret = Opt_update;
+ break;
+ case Opt_err:
+ return -EINVAL;
+ }
+ return ret;
+}
+
+static struct trusted_key_payload *trusted_payload_alloc(struct key *key)
+{
+ struct trusted_key_payload *p = NULL;
+ int ret;
+
+ ret = key_payload_reserve(key, sizeof(*p));
+ if (ret < 0)
+ return p;
+ p = kzalloc(sizeof(*p), GFP_KERNEL);
+
+ p->migratable = tk_ops->migratable;
+
+ return p;
+}
+
+/*
+ * trusted_instantiate - create a new trusted key
+ *
+ * Unseal an existing trusted blob or, for a new key, get a
+ * random key, then seal and create a trusted key-type key,
+ * adding it to the specified keyring.
+ *
+ * On success, return 0. Otherwise return errno.
+ */
+static int trusted_instantiate(struct key *key,
+ struct key_preparsed_payload *prep)
+{
+ struct trusted_key_payload *payload = NULL;
+ size_t datalen = prep->datalen;
+ char *datablob;
+ int ret = 0;
+ int key_cmd;
+ size_t key_len;
+
+ if (datalen <= 0 || datalen > 32767 || !prep->data)
+ return -EINVAL;
+
+ datablob = kmalloc(datalen + 1, GFP_KERNEL);
+ if (!datablob)
+ return -ENOMEM;
+ memcpy(datablob, prep->data, datalen);
+ datablob[datalen] = '\0';
+
+ payload = trusted_payload_alloc(key);
+ if (!payload) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ key_cmd = datablob_parse(datablob, payload);
+ if (key_cmd < 0) {
+ ret = key_cmd;
+ goto out;
+ }
+
+ dump_payload(payload);
+
+ switch (key_cmd) {
+ case Opt_load:
+ ret = tk_ops->unseal(payload, datablob);
+ dump_payload(payload);
+ if (ret < 0)
+ pr_info("trusted_key: key_unseal failed (%d)\n", ret);
+ break;
+ case Opt_new:
+ key_len = payload->key_len;
+ ret = tk_ops->get_random(payload->key, key_len);
+ if (ret != key_len) {
+ pr_info("trusted_key: key_create failed (%d)\n", ret);
+ goto out;
+ }
+
+ ret = tk_ops->seal(payload, datablob);
+ if (ret < 0)
+ pr_info("trusted_key: key_seal failed (%d)\n", ret);
+ break;
+ default:
+ ret = -EINVAL;
+ }
+out:
+ kzfree(datablob);
+ if (!ret)
+ rcu_assign_keypointer(key, payload);
+ else
+ kzfree(payload);
+ return ret;
+}
+
+static void trusted_rcu_free(struct rcu_head *rcu)
+{
+ struct trusted_key_payload *p;
+
+ p = container_of(rcu, struct trusted_key_payload, rcu);
+ kzfree(p);
+}
+
+/*
+ * trusted_update - reseal an existing key with new PCR values
+ */
+static int trusted_update(struct key *key, struct key_preparsed_payload *prep)
+{
+ struct trusted_key_payload *p;
+ struct trusted_key_payload *new_p;
+ size_t datalen = prep->datalen;
+ char *datablob;
+ int ret = 0;
+
+ if (key_is_negative(key))
+ return -ENOKEY;
+ p = key->payload.data[0];
+ if (!p->migratable)
+ return -EPERM;
+ if (datalen <= 0 || datalen > 32767 || !prep->data)
+ return -EINVAL;
+
+ datablob = kmalloc(datalen + 1, GFP_KERNEL);
+ if (!datablob)
+ return -ENOMEM;
+
+ new_p = trusted_payload_alloc(key);
+ if (!new_p) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ memcpy(datablob, prep->data, datalen);
+ datablob[datalen] = '\0';
+ ret = datablob_parse(datablob, new_p);
+ if (ret != Opt_update) {
+ ret = -EINVAL;
+ kzfree(new_p);
+ goto out;
+ }
+
+ /* copy old key values, and reseal with new pcrs */
+ new_p->migratable = p->migratable;
+ new_p->key_len = p->key_len;
+ memcpy(new_p->key, p->key, p->key_len);
+ dump_payload(p);
+ dump_payload(new_p);
+
+ ret = tk_ops->seal(new_p, datablob);
+ if (ret < 0) {
+ pr_info("trusted_key: key_seal failed (%d)\n", ret);
+ kzfree(new_p);
+ goto out;
+ }
+
+ rcu_assign_keypointer(key, new_p);
+ call_rcu(&p->rcu, trusted_rcu_free);
+out:
+ kzfree(datablob);
+ return ret;
+}
+
+/*
+ * trusted_read - copy the sealed blob data to userspace in hex.
+ * On success, return to userspace the trusted key datablob size.
+ */
+static long trusted_read(const struct key *key, char __user *buffer,
+ size_t buflen)
+{
+ const struct trusted_key_payload *p;
+ char *ascii_buf;
+ char *bufp;
+ int i;
+
+ p = dereference_key_locked(key);
+ if (!p)
+ return -EINVAL;
+
+ if (buffer && buflen >= 2 * p->blob_len) {
+ ascii_buf = kmalloc_array(2, p->blob_len, GFP_KERNEL);
+ if (!ascii_buf)
+ return -ENOMEM;
+
+ bufp = ascii_buf;
+ for (i = 0; i < p->blob_len; i++)
+ bufp = hex_byte_pack(bufp, p->blob[i]);
+ if (copy_to_user(buffer, ascii_buf, 2 * p->blob_len) != 0) {
+ kzfree(ascii_buf);
+ return -EFAULT;
+ }
+ kzfree(ascii_buf);
+ }
+ return 2 * p->blob_len;
+}
+
+/*
+ * trusted_destroy - clear and free the key's payload
+ */
+static void trusted_destroy(struct key *key)
+{
+ kzfree(key->payload.data[0]);
+}
+
+struct key_type key_type_trusted = {
+ .name = "trusted",
+ .instantiate = trusted_instantiate,
+ .update = trusted_update,
+ .destroy = trusted_destroy,
+ .describe = user_describe,
+ .read = trusted_read,
+};
+EXPORT_SYMBOL_GPL(key_type_trusted);
+
+static int __init init_trusted(void)
+{
+ int i, ret = 0;
+
+ for (i = 0; i < sizeof(available_tk_ops); i++) {
+ tk_ops = available_tk_ops[i];
+
+ if (!(tk_ops && tk_ops->init && tk_ops->seal &&
+ tk_ops->unseal && tk_ops->get_random))
+ continue;
+
+ ret = tk_ops->init();
+ if (ret) {
+ if (tk_ops->cleanup)
+ tk_ops->cleanup();
+ } else {
+ break;
+ }
+ }
+
+ /*
+ * encrypted_keys.ko depends on successful load of this module even if
+ * trusted key implementation is not found.
+ */
+ if (ret == -ENODEV)
+ return 0;
+
+ return ret;
+}
+
+static void __exit cleanup_trusted(void)
+{
+ if (tk_ops->cleanup)
+ tk_ops->cleanup();
+}
+
+late_initcall(init_trusted);
+module_exit(cleanup_trusted);
+
+MODULE_LICENSE("GPL");
diff --git a/security/keys/trusted-keys/trusted_tpm1.c b/security/keys/trusted-keys/trusted_tpm1.c
index d2c5ec1..32fd1ea 100644
--- a/security/keys/trusted-keys/trusted_tpm1.c
+++ b/security/keys/trusted-keys/trusted_tpm1.c
@@ -1,29 +1,26 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2010 IBM Corporation
+ * Copyright (c) 2019, Linaro Limited
*
* Author:
* David Safford <safford@us.ibm.com>
+ * Switch to generic trusted key framework: Sumit Garg <sumit.garg@linaro.org>
*
* See Documentation/security/keys/trusted-encrypted.rst
*/
#include <crypto/hash_info.h>
-#include <linux/uaccess.h>
-#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/parser.h>
#include <linux/string.h>
#include <linux/err.h>
-#include <keys/user-type.h>
#include <keys/trusted-type.h>
#include <linux/key-type.h>
-#include <linux/rcupdate.h>
#include <linux/crypto.h>
#include <crypto/hash.h>
#include <crypto/sha.h>
-#include <linux/capability.h>
#include <linux/tpm.h>
#include <linux/tpm_command.h>
@@ -703,7 +700,6 @@ static int key_unseal(struct trusted_key_payload *p,
enum {
Opt_err,
- Opt_new, Opt_load, Opt_update,
Opt_keyhandle, Opt_keyauth, Opt_blobauth,
Opt_pcrinfo, Opt_pcrlock, Opt_migratable,
Opt_hash,
@@ -712,9 +708,6 @@ enum {
};
static const match_table_t key_tokens = {
- {Opt_new, "new"},
- {Opt_load, "load"},
- {Opt_update, "update"},
{Opt_keyhandle, "keyhandle=%s"},
{Opt_keyauth, "keyauth=%s"},
{Opt_blobauth, "blobauth=%s"},
@@ -841,71 +834,6 @@ static int getoptions(char *c, struct trusted_key_payload *pay,
return 0;
}
-/*
- * datablob_parse - parse the keyctl data and fill in the
- * payload and options structures
- *
- * On success returns 0, otherwise -EINVAL.
- */
-static int datablob_parse(char *datablob, struct trusted_key_payload *p,
- struct trusted_key_options *o)
-{
- substring_t args[MAX_OPT_ARGS];
- long keylen;
- int ret = -EINVAL;
- int key_cmd;
- char *c;
-
- /* main command */
- c = strsep(&datablob, " \t");
- if (!c)
- return -EINVAL;
- key_cmd = match_token(c, key_tokens, args);
- switch (key_cmd) {
- case Opt_new:
- /* first argument is key size */
- c = strsep(&datablob, " \t");
- if (!c)
- return -EINVAL;
- ret = kstrtol(c, 10, &keylen);
- if (ret < 0 || keylen < MIN_KEY_SIZE || keylen > MAX_KEY_SIZE)
- return -EINVAL;
- p->key_len = keylen;
- ret = getoptions(datablob, p, o);
- if (ret < 0)
- return ret;
- ret = Opt_new;
- break;
- case Opt_load:
- /* first argument is sealed blob */
- c = strsep(&datablob, " \t");
- if (!c)
- return -EINVAL;
- p->blob_len = strlen(c) / 2;
- if (p->blob_len > MAX_BLOB_SIZE)
- return -EINVAL;
- ret = hex2bin(p->blob, c, p->blob_len);
- if (ret < 0)
- return -EINVAL;
- ret = getoptions(datablob, p, o);
- if (ret < 0)
- return ret;
- ret = Opt_load;
- break;
- case Opt_update:
- /* all arguments are options */
- ret = getoptions(datablob, p, o);
- if (ret < 0)
- return ret;
- ret = Opt_update;
- break;
- case Opt_err:
- return -EINVAL;
- break;
- }
- return ret;
-}
-
static struct trusted_key_options *trusted_options_alloc(void)
{
struct trusted_key_options *options;
@@ -926,258 +854,99 @@ static struct trusted_key_options *trusted_options_alloc(void)
return options;
}
-static struct trusted_key_payload *trusted_payload_alloc(struct key *key)
+static int tpm_tk_seal(struct trusted_key_payload *p, char *datablob)
{
- struct trusted_key_payload *p = NULL;
- int ret;
-
- ret = key_payload_reserve(key, sizeof *p);
- if (ret < 0)
- return p;
- p = kzalloc(sizeof *p, GFP_KERNEL);
- if (p)
- p->migratable = 1; /* migratable by default */
- return p;
-}
-
-/*
- * trusted_instantiate - create a new trusted key
- *
- * Unseal an existing trusted blob or, for a new key, get a
- * random key, then seal and create a trusted key-type key,
- * adding it to the specified keyring.
- *
- * On success, return 0. Otherwise return errno.
- */
-static int trusted_instantiate(struct key *key,
- struct key_preparsed_payload *prep)
-{
- struct trusted_key_payload *payload = NULL;
struct trusted_key_options *options = NULL;
- size_t datalen = prep->datalen;
- char *datablob;
int ret = 0;
- int key_cmd;
- size_t key_len;
int tpm2;
tpm2 = tpm_is_tpm2(chip);
if (tpm2 < 0)
return tpm2;
- if (datalen <= 0 || datalen > 32767 || !prep->data)
- return -EINVAL;
-
- datablob = kmalloc(datalen + 1, GFP_KERNEL);
- if (!datablob)
- return -ENOMEM;
- memcpy(datablob, prep->data, datalen);
- datablob[datalen] = '\0';
-
options = trusted_options_alloc();
- if (!options) {
- ret = -ENOMEM;
- goto out;
- }
- payload = trusted_payload_alloc(key);
- if (!payload) {
- ret = -ENOMEM;
- goto out;
- }
+ if (!options)
+ return -ENOMEM;
- key_cmd = datablob_parse(datablob, payload, options);
- if (key_cmd < 0) {
- ret = key_cmd;
+ ret = getoptions(datablob, p, options);
+ if (ret < 0)
goto out;
- }
+ dump_options(options);
if (!options->keyhandle) {
ret = -EINVAL;
goto out;
}
- dump_payload(payload);
- dump_options(options);
+ if (tpm2)
+ ret = tpm2_seal_trusted(chip, p, options);
+ else
+ ret = key_seal(p, options);
+ if (ret < 0) {
+ pr_info("tpm_trusted_key: key_seal failed (%d)\n", ret);
+ goto out;
+ }
- switch (key_cmd) {
- case Opt_load:
- if (tpm2)
- ret = tpm2_unseal_trusted(chip, payload, options);
- else
- ret = key_unseal(payload, options);
- dump_payload(payload);
- dump_options(options);
- if (ret < 0)
- pr_info("trusted_key: key_unseal failed (%d)\n", ret);
- break;
- case Opt_new:
- key_len = payload->key_len;
- ret = tpm_get_random(chip, payload->key, key_len);
- if (ret != key_len) {
- pr_info("trusted_key: key_create failed (%d)\n", ret);
+ if (options->pcrlock) {
+ ret = pcrlock(options->pcrlock);
+ if (ret < 0) {
+ pr_info("tpm_trusted_key: pcrlock failed (%d)\n", ret);
goto out;
}
- if (tpm2)
- ret = tpm2_seal_trusted(chip, payload, options);
- else
- ret = key_seal(payload, options);
- if (ret < 0)
- pr_info("trusted_key: key_seal failed (%d)\n", ret);
- break;
- default:
- ret = -EINVAL;
- goto out;
}
- if (!ret && options->pcrlock)
- ret = pcrlock(options->pcrlock);
out:
- kzfree(datablob);
kzfree(options);
- if (!ret)
- rcu_assign_keypointer(key, payload);
- else
- kzfree(payload);
return ret;
}
-static void trusted_rcu_free(struct rcu_head *rcu)
-{
- struct trusted_key_payload *p;
-
- p = container_of(rcu, struct trusted_key_payload, rcu);
- kzfree(p);
-}
-
-/*
- * trusted_update - reseal an existing key with new PCR values
- */
-static int trusted_update(struct key *key, struct key_preparsed_payload *prep)
+static int tpm_tk_unseal(struct trusted_key_payload *p, char *datablob)
{
- struct trusted_key_payload *p;
- struct trusted_key_payload *new_p;
- struct trusted_key_options *new_o;
- size_t datalen = prep->datalen;
- char *datablob;
+ struct trusted_key_options *options = NULL;
int ret = 0;
+ int tpm2;
- if (key_is_negative(key))
- return -ENOKEY;
- p = key->payload.data[0];
- if (!p->migratable)
- return -EPERM;
- if (datalen <= 0 || datalen > 32767 || !prep->data)
- return -EINVAL;
+ tpm2 = tpm_is_tpm2(chip);
+ if (tpm2 < 0)
+ return tpm2;
- datablob = kmalloc(datalen + 1, GFP_KERNEL);
- if (!datablob)
+ options = trusted_options_alloc();
+ if (!options)
return -ENOMEM;
- new_o = trusted_options_alloc();
- if (!new_o) {
- ret = -ENOMEM;
- goto out;
- }
- new_p = trusted_payload_alloc(key);
- if (!new_p) {
- ret = -ENOMEM;
- goto out;
- }
- memcpy(datablob, prep->data, datalen);
- datablob[datalen] = '\0';
- ret = datablob_parse(datablob, new_p, new_o);
- if (ret != Opt_update) {
- ret = -EINVAL;
- kzfree(new_p);
+ ret = getoptions(datablob, p, options);
+ if (ret < 0)
goto out;
- }
+ dump_options(options);
- if (!new_o->keyhandle) {
+ if (!options->keyhandle) {
ret = -EINVAL;
- kzfree(new_p);
goto out;
}
- /* copy old key values, and reseal with new pcrs */
- new_p->migratable = p->migratable;
- new_p->key_len = p->key_len;
- memcpy(new_p->key, p->key, p->key_len);
- dump_payload(p);
- dump_payload(new_p);
+ if (tpm2)
+ ret = tpm2_unseal_trusted(chip, p, options);
+ else
+ ret = key_unseal(p, options);
+ if (ret < 0)
+ pr_info("tpm_trusted_key: key_unseal failed (%d)\n", ret);
- ret = key_seal(new_p, new_o);
- if (ret < 0) {
- pr_info("trusted_key: key_seal failed (%d)\n", ret);
- kzfree(new_p);
- goto out;
- }
- if (new_o->pcrlock) {
- ret = pcrlock(new_o->pcrlock);
+ if (options->pcrlock) {
+ ret = pcrlock(options->pcrlock);
if (ret < 0) {
- pr_info("trusted_key: pcrlock failed (%d)\n", ret);
- kzfree(new_p);
+ pr_info("tpm_trusted_key: pcrlock failed (%d)\n", ret);
goto out;
}
}
- rcu_assign_keypointer(key, new_p);
- call_rcu(&p->rcu, trusted_rcu_free);
out:
- kzfree(datablob);
- kzfree(new_o);
+ kzfree(options);
return ret;
}
-/*
- * trusted_read - copy the sealed blob data to userspace in hex.
- * On success, return to userspace the trusted key datablob size.
- */
-static long trusted_read(const struct key *key, char __user *buffer,
- size_t buflen)
-{
- const struct trusted_key_payload *p;
- char *ascii_buf;
- char *bufp;
- int i;
-
- p = dereference_key_locked(key);
- if (!p)
- return -EINVAL;
-
- if (buffer && buflen >= 2 * p->blob_len) {
- ascii_buf = kmalloc_array(2, p->blob_len, GFP_KERNEL);
- if (!ascii_buf)
- return -ENOMEM;
-
- bufp = ascii_buf;
- for (i = 0; i < p->blob_len; i++)
- bufp = hex_byte_pack(bufp, p->blob[i]);
- if (copy_to_user(buffer, ascii_buf, 2 * p->blob_len) != 0) {
- kzfree(ascii_buf);
- return -EFAULT;
- }
- kzfree(ascii_buf);
- }
- return 2 * p->blob_len;
-}
-
-/*
- * trusted_destroy - clear and free the key's payload
- */
-static void trusted_destroy(struct key *key)
+int tpm_tk_get_random(unsigned char *key, size_t key_len)
{
- kzfree(key->payload.data[0]);
+ return tpm_get_random(chip, key, key_len);
}
-struct key_type key_type_trusted = {
- .name = "trusted",
- .instantiate = trusted_instantiate,
- .update = trusted_update,
- .destroy = trusted_destroy,
- .describe = user_describe,
- .read = trusted_read,
-};
-
-EXPORT_SYMBOL_GPL(key_type_trusted);
-
static void trusted_shash_release(void)
{
if (hashalg)
@@ -1192,14 +961,14 @@ static int __init trusted_shash_alloc(void)
hmacalg = crypto_alloc_shash(hmac_alg, 0, 0);
if (IS_ERR(hmacalg)) {
- pr_info("trusted_key: could not allocate crypto %s\n",
+ pr_info("tpm_trusted_key: could not allocate crypto %s\n",
hmac_alg);
return PTR_ERR(hmacalg);
}
hashalg = crypto_alloc_shash(hash_alg, 0, 0);
if (IS_ERR(hashalg)) {
- pr_info("trusted_key: could not allocate crypto %s\n",
+ pr_info("tpm_trusted_key: could not allocate crypto %s\n",
hash_alg);
ret = PTR_ERR(hashalg);
goto hashalg_fail;
@@ -1227,16 +996,13 @@ static int __init init_digests(void)
return 0;
}
-static int __init init_trusted(void)
+static int __init init_tpm_trusted(void)
{
int ret;
- /* encrypted_keys.ko depends on successful load of this module even if
- * TPM is not used.
- */
chip = tpm_default_chip();
if (!chip)
- return 0;
+ return -ENODEV;
ret = init_digests();
if (ret < 0)
@@ -1257,7 +1023,7 @@ static int __init init_trusted(void)
return ret;
}
-static void __exit cleanup_trusted(void)
+static void __exit cleanup_tpm_trusted(void)
{
if (chip) {
put_device(&chip->dev);
@@ -1267,7 +1033,12 @@ static void __exit cleanup_trusted(void)
}
}
-late_initcall(init_trusted);
-module_exit(cleanup_trusted);
-
-MODULE_LICENSE("GPL");
+struct trusted_key_ops tpm_trusted_key_ops = {
+ .migratable = 1, /* migratable by default */
+ .init = init_tpm_trusted,
+ .seal = tpm_tk_seal,
+ .unseal = tpm_tk_unseal,
+ .get_random = tpm_tk_get_random,
+ .cleanup = cleanup_tpm_trusted,
+};
+EXPORT_SYMBOL_GPL(tpm_trusted_key_ops);
--
2.7.4
^ permalink raw reply related [flat|nested] 13+ messages in thread* [Patch v3 5/7] KEYS: trusted: Introduce TEE based Trusted Keys
2019-10-31 13:58 [Patch v3 0/7] Introduce TEE based Trusted Keys support Sumit Garg
` (3 preceding siblings ...)
2019-10-31 13:58 ` [Patch v3 4/7] KEYS: trusted: Add generic trusted keys framework Sumit Garg
@ 2019-10-31 13:58 ` Sumit Garg
2019-10-31 13:58 ` [Patch v3 6/7] doc: keys: Document usage of " Sumit Garg
2019-10-31 13:58 ` [Patch v3 7/7] MAINTAINERS: Add entry for " Sumit Garg
6 siblings, 0 replies; 13+ messages in thread
From: Sumit Garg @ 2019-10-31 13:58 UTC (permalink / raw)
To: jens.wiklander, jarkko.sakkinen, dhowells
Cc: corbet, jejb, zohar, jmorris, serge, casey, ard.biesheuvel,
daniel.thompson, stuart.yoder, janne.karhunen, keyrings,
linux-integrity, linux-security-module, linux-doc, linux-kernel,
linux-arm-kernel, tee-dev, Sumit Garg
Add support for TEE based trusted keys where TEE provides the functionality
to seal and unseal trusted keys using hardware unique key.
Refer to Documentation/tee.txt for detailed information about TEE.
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
---
include/keys/trusted-type.h | 3 +
include/keys/trusted_tee.h | 66 +++++++
security/keys/Kconfig | 3 +
security/keys/trusted-keys/Makefile | 1 +
security/keys/trusted-keys/trusted_common.c | 3 +
security/keys/trusted-keys/trusted_tee.c | 282 ++++++++++++++++++++++++++++
6 files changed, 358 insertions(+)
create mode 100644 include/keys/trusted_tee.h
create mode 100644 security/keys/trusted-keys/trusted_tee.c
diff --git a/include/keys/trusted-type.h b/include/keys/trusted-type.h
index 5559010..e0df5df 100644
--- a/include/keys/trusted-type.h
+++ b/include/keys/trusted-type.h
@@ -67,6 +67,9 @@ extern struct key_type key_type_trusted;
#if defined(CONFIG_TCG_TPM)
extern struct trusted_key_ops tpm_trusted_key_ops;
#endif
+#if defined(CONFIG_TEE)
+extern struct trusted_key_ops tee_trusted_key_ops;
+#endif
#define TRUSTED_DEBUG 0
diff --git a/include/keys/trusted_tee.h b/include/keys/trusted_tee.h
new file mode 100644
index 0000000..ab58ffd
--- /dev/null
+++ b/include/keys/trusted_tee.h
@@ -0,0 +1,66 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019 Linaro Ltd.
+ *
+ * Author:
+ * Sumit Garg <sumit.garg@linaro.org>
+ */
+
+#ifndef __TEE_TRUSTED_KEY_H
+#define __TEE_TRUSTED_KEY_H
+
+#include <linux/tee_drv.h>
+
+#define DRIVER_NAME "tee-trusted-key"
+
+/*
+ * Get random data for symmetric key
+ *
+ * [out] memref[0] Random data
+ *
+ * Result:
+ * TEE_SUCCESS - Invoke command success
+ * TEE_ERROR_BAD_PARAMETERS - Incorrect input param
+ */
+#define TA_CMD_GET_RANDOM 0x0
+
+/*
+ * Seal trusted key using hardware unique key
+ *
+ * [in] memref[0] Plain key
+ * [out] memref[1] Sealed key datablob
+ *
+ * Result:
+ * TEE_SUCCESS - Invoke command success
+ * TEE_ERROR_BAD_PARAMETERS - Incorrect input param
+ */
+#define TA_CMD_SEAL 0x1
+
+/*
+ * Unseal trusted key using hardware unique key
+ *
+ * [in] memref[0] Sealed key datablob
+ * [out] memref[1] Plain key
+ *
+ * Result:
+ * TEE_SUCCESS - Invoke command success
+ * TEE_ERROR_BAD_PARAMETERS - Incorrect input param
+ */
+#define TA_CMD_UNSEAL 0x2
+
+/**
+ * struct trusted_key_private - TEE Trusted key private data
+ * @dev: TEE based Trusted key device.
+ * @ctx: TEE context handler.
+ * @session_id: Trusted key TA session identifier.
+ * @shm_pool: Memory pool shared with TEE device.
+ */
+struct trusted_key_private {
+ struct device *dev;
+ struct tee_context *ctx;
+ u32 session_id;
+ u32 data_rate;
+ struct tee_shm *shm_pool;
+};
+
+#endif
diff --git a/security/keys/Kconfig b/security/keys/Kconfig
index dd31343..0d5e37c 100644
--- a/security/keys/Kconfig
+++ b/security/keys/Kconfig
@@ -88,6 +88,9 @@ config TRUSTED_KEYS
if the boot PCRs and other criteria match. Userspace will only ever
see encrypted blobs.
+ It also provides support for alternative TEE based Trusted keys
+ generation and sealing in case TPM isn't present.
+
If you are unsure as to whether this is required, answer N.
config ENCRYPTED_KEYS
diff --git a/security/keys/trusted-keys/Makefile b/security/keys/trusted-keys/Makefile
index 2b1085b..ea937d3 100644
--- a/security/keys/trusted-keys/Makefile
+++ b/security/keys/trusted-keys/Makefile
@@ -7,3 +7,4 @@ obj-$(CONFIG_TRUSTED_KEYS) += trusted.o
trusted-y += trusted_common.o
trusted-y += trusted_tpm1.o
trusted-y += trusted_tpm2.o
+trusted-y += trusted_tee.o
diff --git a/security/keys/trusted-keys/trusted_common.c b/security/keys/trusted-keys/trusted_common.c
index 8f00fde..a0a171f 100644
--- a/security/keys/trusted-keys/trusted_common.c
+++ b/security/keys/trusted-keys/trusted_common.c
@@ -27,6 +27,9 @@ static struct trusted_key_ops *available_tk_ops[] = {
#if defined(CONFIG_TCG_TPM)
&tpm_trusted_key_ops,
#endif
+#if defined(CONFIG_TEE)
+ &tee_trusted_key_ops,
+#endif
};
static struct trusted_key_ops *tk_ops;
diff --git a/security/keys/trusted-keys/trusted_tee.c b/security/keys/trusted-keys/trusted_tee.c
new file mode 100644
index 0000000..724a73c
--- /dev/null
+++ b/security/keys/trusted-keys/trusted_tee.c
@@ -0,0 +1,282 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 Linaro Ltd.
+ *
+ * Author:
+ * Sumit Garg <sumit.garg@linaro.org>
+ */
+
+#include <linux/err.h>
+#include <linux/key-type.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/uuid.h>
+
+#include <keys/trusted-type.h>
+#include <keys/trusted_tee.h>
+
+static struct trusted_key_private pvt_data;
+
+/*
+ * Have the TEE seal(encrypt) the symmetric key
+ */
+static int tee_key_seal(struct trusted_key_payload *p, char *datablob)
+{
+ int ret = 0;
+ struct tee_ioctl_invoke_arg inv_arg;
+ struct tee_param param[4];
+ struct tee_shm *reg_shm_in = NULL, *reg_shm_out = NULL;
+
+ memset(&inv_arg, 0, sizeof(inv_arg));
+ memset(¶m, 0, sizeof(param));
+
+ reg_shm_in = tee_shm_register(pvt_data.ctx, (unsigned long)p->key,
+ p->key_len, TEE_SHM_DMA_BUF |
+ TEE_SHM_KERNEL_MAPPED);
+ if (IS_ERR(reg_shm_in)) {
+ dev_err(pvt_data.dev, "key shm register failed\n");
+ return PTR_ERR(reg_shm_in);
+ }
+
+ reg_shm_out = tee_shm_register(pvt_data.ctx, (unsigned long)p->blob,
+ sizeof(p->blob), TEE_SHM_DMA_BUF |
+ TEE_SHM_KERNEL_MAPPED);
+ if (IS_ERR(reg_shm_out)) {
+ dev_err(pvt_data.dev, "blob shm register failed\n");
+ ret = PTR_ERR(reg_shm_out);
+ goto out;
+ }
+
+ inv_arg.func = TA_CMD_SEAL;
+ inv_arg.session = pvt_data.session_id;
+ inv_arg.num_params = 4;
+
+ param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT;
+ param[0].u.memref.shm = reg_shm_in;
+ param[0].u.memref.size = p->key_len;
+ param[0].u.memref.shm_offs = 0;
+ param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT;
+ param[1].u.memref.shm = reg_shm_out;
+ param[1].u.memref.size = sizeof(p->blob);
+ param[1].u.memref.shm_offs = 0;
+
+ ret = tee_client_invoke_func(pvt_data.ctx, &inv_arg, param);
+ if ((ret < 0) || (inv_arg.ret != 0)) {
+ dev_err(pvt_data.dev, "TA_CMD_SEAL invoke err: %x\n",
+ inv_arg.ret);
+ ret = -EFAULT;
+ } else {
+ p->blob_len = param[1].u.memref.size;
+ }
+
+out:
+ if (reg_shm_out)
+ tee_shm_free(reg_shm_out);
+ if (reg_shm_in)
+ tee_shm_free(reg_shm_in);
+
+ return ret;
+}
+
+/*
+ * Have the TEE unseal(decrypt) the symmetric key
+ */
+static int tee_key_unseal(struct trusted_key_payload *p, char *datablob)
+{
+ int ret = 0;
+ struct tee_ioctl_invoke_arg inv_arg;
+ struct tee_param param[4];
+ struct tee_shm *reg_shm_in = NULL, *reg_shm_out = NULL;
+
+ memset(&inv_arg, 0, sizeof(inv_arg));
+ memset(¶m, 0, sizeof(param));
+
+ reg_shm_in = tee_shm_register(pvt_data.ctx, (unsigned long)p->blob,
+ p->blob_len, TEE_SHM_DMA_BUF |
+ TEE_SHM_KERNEL_MAPPED);
+ if (IS_ERR(reg_shm_in)) {
+ dev_err(pvt_data.dev, "blob shm register failed\n");
+ return PTR_ERR(reg_shm_in);
+ }
+
+ reg_shm_out = tee_shm_register(pvt_data.ctx, (unsigned long)p->key,
+ sizeof(p->key), TEE_SHM_DMA_BUF |
+ TEE_SHM_KERNEL_MAPPED);
+ if (IS_ERR(reg_shm_out)) {
+ dev_err(pvt_data.dev, "key shm register failed\n");
+ ret = PTR_ERR(reg_shm_out);
+ goto out;
+ }
+
+ inv_arg.func = TA_CMD_UNSEAL;
+ inv_arg.session = pvt_data.session_id;
+ inv_arg.num_params = 4;
+
+ param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT;
+ param[0].u.memref.shm = reg_shm_in;
+ param[0].u.memref.size = p->blob_len;
+ param[0].u.memref.shm_offs = 0;
+ param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT;
+ param[1].u.memref.shm = reg_shm_out;
+ param[1].u.memref.size = sizeof(p->key);
+ param[1].u.memref.shm_offs = 0;
+
+ ret = tee_client_invoke_func(pvt_data.ctx, &inv_arg, param);
+ if ((ret < 0) || (inv_arg.ret != 0)) {
+ dev_err(pvt_data.dev, "TA_CMD_UNSEAL invoke err: %x\n",
+ inv_arg.ret);
+ ret = -EFAULT;
+ } else {
+ p->key_len = param[1].u.memref.size;
+ }
+
+out:
+ if (reg_shm_out)
+ tee_shm_free(reg_shm_out);
+ if (reg_shm_in)
+ tee_shm_free(reg_shm_in);
+
+ return ret;
+}
+
+/*
+ * Have the TEE generate random symmetric key
+ */
+static int tee_get_random(unsigned char *key, size_t key_len)
+{
+ int ret = 0;
+ struct tee_ioctl_invoke_arg inv_arg;
+ struct tee_param param[4];
+ struct tee_shm *reg_shm = NULL;
+
+ memset(&inv_arg, 0, sizeof(inv_arg));
+ memset(¶m, 0, sizeof(param));
+
+ reg_shm = tee_shm_register(pvt_data.ctx, (unsigned long)key, key_len,
+ TEE_SHM_DMA_BUF | TEE_SHM_KERNEL_MAPPED);
+ if (IS_ERR(reg_shm)) {
+ dev_err(pvt_data.dev, "random key shm register failed\n");
+ return PTR_ERR(reg_shm);
+ }
+
+ inv_arg.func = TA_CMD_GET_RANDOM;
+ inv_arg.session = pvt_data.session_id;
+ inv_arg.num_params = 4;
+
+ param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT;
+ param[0].u.memref.shm = reg_shm;
+ param[0].u.memref.size = key_len;
+ param[0].u.memref.shm_offs = 0;
+
+ ret = tee_client_invoke_func(pvt_data.ctx, &inv_arg, param);
+ if ((ret < 0) || (inv_arg.ret != 0)) {
+ dev_err(pvt_data.dev, "TA_CMD_GET_RANDOM invoke err: %x\n",
+ inv_arg.ret);
+ ret = -EFAULT;
+ } else {
+ ret = param[0].u.memref.size;
+ }
+
+ tee_shm_free(reg_shm);
+
+ return ret;
+}
+
+static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
+{
+ if (ver->impl_id == TEE_IMPL_ID_OPTEE)
+ return 1;
+ else
+ return 0;
+}
+
+static int trusted_key_probe(struct device *dev)
+{
+ struct tee_client_device *rng_device = to_tee_client_device(dev);
+ int ret = 0, err = -ENODEV;
+ struct tee_ioctl_open_session_arg sess_arg;
+
+ memset(&sess_arg, 0, sizeof(sess_arg));
+
+ /* Open context with TEE driver */
+ pvt_data.ctx = tee_client_open_context(NULL, optee_ctx_match, NULL,
+ NULL);
+ if (IS_ERR(pvt_data.ctx))
+ return -ENODEV;
+
+ /* Open session with hwrng Trusted App */
+ memcpy(sess_arg.uuid, rng_device->id.uuid.b, TEE_IOCTL_UUID_LEN);
+ sess_arg.clnt_login = TEE_IOCTL_LOGIN_REE_KERNEL;
+ sess_arg.num_params = 0;
+
+ ret = tee_client_open_session(pvt_data.ctx, &sess_arg, NULL);
+ if ((ret < 0) || (sess_arg.ret != 0)) {
+ dev_err(dev, "tee_client_open_session failed, err: %x\n",
+ sess_arg.ret);
+ err = -EINVAL;
+ goto out_ctx;
+ }
+ pvt_data.session_id = sess_arg.session;
+
+ ret = register_key_type(&key_type_trusted);
+ if (ret < 0)
+ goto out_sess;
+
+ pvt_data.dev = dev;
+
+ return 0;
+
+out_sess:
+ tee_client_close_session(pvt_data.ctx, pvt_data.session_id);
+out_ctx:
+ tee_client_close_context(pvt_data.ctx);
+
+ return err;
+}
+
+static int trusted_key_remove(struct device *dev)
+{
+ unregister_key_type(&key_type_trusted);
+ tee_client_close_session(pvt_data.ctx, pvt_data.session_id);
+ tee_client_close_context(pvt_data.ctx);
+
+ return 0;
+}
+
+static const struct tee_client_device_id trusted_key_id_table[] = {
+ {UUID_INIT(0xf04a0fe7, 0x1f5d, 0x4b9b,
+ 0xab, 0xf7, 0x61, 0x9b, 0x85, 0xb4, 0xce, 0x8c)},
+ {}
+};
+
+MODULE_DEVICE_TABLE(tee, trusted_key_id_table);
+
+static struct tee_client_driver trusted_key_driver = {
+ .id_table = trusted_key_id_table,
+ .driver = {
+ .name = DRIVER_NAME,
+ .bus = &tee_bus_type,
+ .probe = trusted_key_probe,
+ .remove = trusted_key_remove,
+ },
+};
+
+static int __init init_tee_trusted(void)
+{
+ return driver_register(&trusted_key_driver.driver);
+}
+
+static void __exit cleanup_tee_trusted(void)
+{
+ driver_unregister(&trusted_key_driver.driver);
+}
+
+struct trusted_key_ops tee_trusted_key_ops = {
+ .migratable = 0, /* non-migratable */
+ .init = init_tee_trusted,
+ .seal = tee_key_seal,
+ .unseal = tee_key_unseal,
+ .get_random = tee_get_random,
+ .cleanup = cleanup_tee_trusted,
+};
+EXPORT_SYMBOL_GPL(tee_trusted_key_ops);
--
2.7.4
^ permalink raw reply related [flat|nested] 13+ messages in thread