[RFC PATCH v2 0/4] crypto: (ec)dh - add privkey generation support

[RFC PATCH v2 0/4] crypto: (ec)dh - add privkey generation support

[Tudor Ambarus]

Hi,

This is an RFC to discuss how to support private key generation for dh and ecdh.

This is helpful in a user-space to kernel (ec)dh offload because the keys are
generated in kernel and never revealed to user-space.

Private key generation is also helpful to implement forward secrecy.
A public/private key system demonstrates the property of forward secrecy if it
creates new key pairs for each communication session. These key pairs are
generated on an as-needed basis and are destroyed after the session is over.
If an attacker were to record previous encrypted session data, they wouldn't be
able to decrypt it with possession of a long-term key.

There are crypto accelerators that are capable of generating and retaining
private keys without revealing them to software. This patch set is a
prerequisite for hardware private key generation support.

Changes in v2:
 - free dh params in case of error
 - code defensively in testmgr: use sizeof(*ptr) while in memcpy

v1 can be found at:
http://www.mail-archive.com/linux-crypto@vger.kernel.org/msg25176.html

Tudor Ambarus (4):
  crypto: ecc - add privkey generation support
  crypto: ecdh - allow user to provide NULL privkey
  crypto: dh - allow user to provide NULL privkey
  crypto: testmgr - add genkey kpp test

 crypto/dh.c      |  21 ++++++++
 crypto/ecc.c     |  20 +++++++
 crypto/ecc.h     |  14 +++++
 crypto/ecdh.c    |   4 ++
 crypto/testmgr.c |  76 +++++++++++++++++++++++----
 crypto/testmgr.h | 155 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 6 files changed, 279 insertions(+), 11 deletions(-)

-- 
2.7.4

[RFC PATCH v2 1/4] crypto: ecc - add privkey generation support

[Tudor Ambarus]

Add support for generating ecc private keys.

Generation of ecc private keys is helpful in a user-space to kernel
ecdh offload because the keys are not revealed to user-space. Private
key generation is also helpful to implement forward secrecy.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
---
 crypto/ecc.c | 20 ++++++++++++++++++++
 crypto/ecc.h | 14 ++++++++++++++
 2 files changed, 34 insertions(+)

diff --git a/crypto/ecc.c b/crypto/ecc.c
index 414c78a..a591907 100644
--- a/crypto/ecc.c
+++ b/crypto/ecc.c
@@ -927,6 +927,26 @@ int ecc_is_key_valid(unsigned int curve_id, unsigned int ndigits,
 	return 0;
 }
 
+int ecc_gen_privkey(unsigned int curve_id, unsigned int ndigits, u64 *privkey)
+{
+	const struct ecc_curve *curve = ecc_get_curve(curve_id);
+	u64 priv[ndigits];
+	unsigned int nbytes = ndigits << ECC_DIGITS_TO_BYTES_SHIFT;
+
+	get_random_bytes(priv, nbytes);
+
+	if (vli_is_zero(priv, ndigits))
+		return -EINVAL;
+
+	/* Make sure the private key is in the range [1, n-1]. */
+	if (vli_cmp(curve->n, priv, ndigits) != 1)
+		return -EINVAL;
+
+	ecc_swap_digits(priv, privkey, ndigits);
+
+	return 0;
+}
+
 int ecdh_make_pub_key(unsigned int curve_id, unsigned int ndigits,
 		      const u8 *private_key, unsigned int private_key_len,
 		      u8 *public_key, unsigned int public_key_len)
diff --git a/crypto/ecc.h b/crypto/ecc.h
index 663d598..b94b7ce 100644
--- a/crypto/ecc.h
+++ b/crypto/ecc.h
@@ -44,6 +44,20 @@ int ecc_is_key_valid(unsigned int curve_id, unsigned int ndigits,
 		     const u8 *private_key, unsigned int private_key_len);
 
 /**
+ * ecc_gen_privkey() -  Generates an ECC private key.
+ * The private key is a random integer in the range 0 < random < n, where n is a
+ * prime that is the order of the cyclic subgroup generated by the distinguished
+ * point G.
+ * @curve_id:		id representing the curve to use
+ * @ndigits:		curve number of digits
+ * @private_key:	buffer for storing the generated private key
+ *
+ * Returns 0 if the private key was generated successfully, a negative value
+ * if an error occurred.
+ */
+int ecc_gen_privkey(unsigned int curve_id, unsigned int ndigits, u64 *privkey);
+
+/**
  * ecdh_make_pub_key() - Compute an ECC public key
  *
  * @curve_id:		id representing the curve to use
-- 
2.7.4

[RFC PATCH v2 2/4] crypto: ecdh - allow user to provide NULL privkey

[Tudor Ambarus]

If the user provides a NULL ecc private key, the kernel will
generate it and further use it for ecdh.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
---
 crypto/ecdh.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/crypto/ecdh.c b/crypto/ecdh.c
index 63ca337..f28f5b5 100644
--- a/crypto/ecdh.c
+++ b/crypto/ecdh.c
@@ -55,6 +55,10 @@ static int ecdh_set_secret(struct crypto_kpp *tfm, const void *buf,
 	ctx->curve_id = params.curve_id;
 	ctx->ndigits = ndigits;
 
+	if (!params.key || !params.key_size)
+		return ecc_gen_privkey(ctx->curve_id, ctx->ndigits,
+				       ctx->private_key);
+
 	if (ecc_is_key_valid(ctx->curve_id, ctx->ndigits,
 			     (const u8 *)params.key, params.key_size) < 0)
 		return -EINVAL;
-- 
2.7.4

[RFC PATCH v2 3/4] crypto: dh - allow user to provide NULL privkey

[Tudor Ambarus]

If the user provides a NULL private key, the kernel will
generate it and further use it for dh.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
---
 crypto/dh.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/crypto/dh.c b/crypto/dh.c
index 87e3542..7b4ac5b 100644
--- a/crypto/dh.c
+++ b/crypto/dh.c
@@ -83,7 +83,9 @@ static int dh_set_secret(struct crypto_kpp *tfm, const void *buf,
 			 unsigned int len)
 {
 	struct dh_ctx *ctx = dh_get_ctx(tfm);
+	u8 *rndbuf = NULL;
 	struct dh params;
+	int maxsize;
 
 	if (crypto_dh_decode_key(buf, len, &params) < 0)
 		return -EINVAL;
@@ -91,7 +93,26 @@ static int dh_set_secret(struct crypto_kpp *tfm, const void *buf,
 	if (dh_set_params(ctx, &params) < 0)
 		return -EINVAL;
 
+	if (!params.key || !params.key_size) {
+		maxsize = crypto_kpp_maxsize(tfm);
+		if (maxsize < 0) {
+			dh_clear_params(ctx);
+			return maxsize;
+		}
+
+		rndbuf = kmalloc(maxsize, GFP_KERNEL);
+		if (!rndbuf) {
+			dh_clear_params(ctx);
+			return -ENOMEM;
+		}
+
+		get_random_bytes(rndbuf, maxsize);
+		params.key = rndbuf;
+		params.key_size = maxsize;
+	}
+
 	ctx->xa = mpi_read_raw_data(params.key, params.key_size);
+	kzfree(rndbuf);
 	if (!ctx->xa) {
 		dh_clear_params(ctx);
 		return -EINVAL;
-- 
2.7.4

[RFC PATCH v2 4/4] crypto: testmgr - add genkey kpp test

[Tudor Ambarus]

The test considers a party that already has a private-public
key pair and a party that provides a NULL key. The kernel will
generate the private-public key pair for the latter, computes
the shared secret on both ends and verifies it it's the same.

The explicit private-public key pairs were copied from
the previous test vectors.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
---
 crypto/testmgr.c |  76 +++++++++++++++++++++++----
 crypto/testmgr.h | 155 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 220 insertions(+), 11 deletions(-)

diff --git a/crypto/testmgr.c b/crypto/testmgr.c
index 6f5f3ed..faf5fd8 100644
--- a/crypto/testmgr.c
+++ b/crypto/testmgr.c
@@ -1997,6 +1997,9 @@ static int do_test_kpp(struct crypto_kpp *tfm, const struct kpp_testvec *vec,
 	struct kpp_request *req;
 	void *input_buf = NULL;
 	void *output_buf = NULL;
+	void *a_public = NULL;
+	void *a_ss = NULL;
+	void *shared_secret = NULL;
 	struct tcrypt_result result;
 	unsigned int out_len_max;
 	int err = -ENOMEM;
@@ -2026,20 +2029,31 @@ static int do_test_kpp(struct crypto_kpp *tfm, const struct kpp_testvec *vec,
 	kpp_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
 				 tcrypt_complete, &result);
 
-	/* Compute public key */
+	/* Compute party A's public key */
 	err = wait_async_op(&result, crypto_kpp_generate_public_key(req));
 	if (err) {
-		pr_err("alg: %s: generate public key test failed. err %d\n",
+		pr_err("alg: %s: Party A: generate public key test failed. err %d\n",
 		       alg, err);
 		goto free_output;
 	}
-	/* Verify calculated public key */
-	if (memcmp(vec->expected_a_public, sg_virt(req->dst),
-		   vec->expected_a_public_size)) {
-		pr_err("alg: %s: generate public key test failed. Invalid output\n",
-		       alg);
-		err = -EINVAL;
-		goto free_output;
+
+	if (vec->genkey) {
+		/* Save party A's public key */
+		a_public = kzalloc(out_len_max, GFP_KERNEL);
+		if (!a_public) {
+			err = -ENOMEM;
+			goto free_output;
+		}
+		memcpy(a_public, sg_virt(req->dst), sizeof(*a_public));
+	} else {
+		/* Verify calculated public key */
+		if (memcmp(vec->expected_a_public, sg_virt(req->dst),
+			   vec->expected_a_public_size)) {
+			pr_err("alg: %s: Party A: generate public key test failed. Invalid output\n",
+			       alg);
+			err = -EINVAL;
+			goto free_output;
+		}
 	}
 
 	/* Calculate shared secret key by using counter part (b) public key. */
@@ -2058,15 +2072,53 @@ static int do_test_kpp(struct crypto_kpp *tfm, const struct kpp_testvec *vec,
 				 tcrypt_complete, &result);
 	err = wait_async_op(&result, crypto_kpp_compute_shared_secret(req));
 	if (err) {
-		pr_err("alg: %s: compute shard secret test failed. err %d\n",
+		pr_err("alg: %s: Party A: compute shared secret test failed. err %d\n",
 		       alg, err);
 		goto free_all;
 	}
+
+	if (vec->genkey) {
+		/* Save the shared secret obtained by party A */
+		a_ss = kzalloc(vec->expected_ss_size, GFP_KERNEL);
+		if (!a_ss) {
+			err = -ENOMEM;
+			goto free_all;
+		}
+		memcpy(a_ss, sg_virt(req->dst), sizeof(*a_ss));
+
+		/*
+		 * Calculate party B's shared secret by using party A's
+		 * public key.
+		 */
+		err = crypto_kpp_set_secret(tfm, vec->b_secret,
+					    vec->b_secret_size);
+		if (err < 0)
+			goto free_all;
+
+		sg_init_one(&src, a_public, vec->expected_a_public_size);
+		sg_init_one(&dst, output_buf, out_len_max);
+		kpp_request_set_input(req, &src, vec->expected_a_public_size);
+		kpp_request_set_output(req, &dst, out_len_max);
+		kpp_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
+					 tcrypt_complete, &result);
+		err = wait_async_op(&result,
+				    crypto_kpp_compute_shared_secret(req));
+		if (err) {
+			pr_err("alg: %s: Party B: compute shared secret failed. err %d\n",
+			       alg, err);
+			goto free_all;
+		}
+
+		shared_secret = a_ss;
+	} else {
+		shared_secret = (void *)vec->expected_ss;
+	}
+
 	/*
 	 * verify shared secret from which the user will derive
 	 * secret key by executing whatever hash it has chosen
 	 */
-	if (memcmp(vec->expected_ss, sg_virt(req->dst),
+	if (memcmp(shared_secret, sg_virt(req->dst),
 		   vec->expected_ss_size)) {
 		pr_err("alg: %s: compute shared secret test failed. Invalid output\n",
 		       alg);
@@ -2074,8 +2126,10 @@ static int do_test_kpp(struct crypto_kpp *tfm, const struct kpp_testvec *vec,
 	}
 
 free_all:
+	kfree(a_ss);
 	kfree(input_buf);
 free_output:
+	kfree(a_public);
 	kfree(output_buf);
 free_req:
 	kpp_request_free(req);
diff --git a/crypto/testmgr.h b/crypto/testmgr.h
index 4293573..a6c6b24 100644
--- a/crypto/testmgr.h
+++ b/crypto/testmgr.h
@@ -137,13 +137,16 @@ struct akcipher_testvec {
 
 struct kpp_testvec {
 	const unsigned char *secret;
+	const unsigned char *b_secret;
 	const unsigned char *b_public;
 	const unsigned char *expected_a_public;
 	const unsigned char *expected_ss;
 	unsigned short secret_size;
+	unsigned short b_secret_size;
 	unsigned short b_public_size;
 	unsigned short expected_a_public_size;
 	unsigned short expected_ss_size;
+	bool genkey;
 };
 
 static const char zeroed_string[48];
@@ -752,6 +755,114 @@ static const struct kpp_testvec dh_tv_template[] = {
 	.b_public_size = 256,
 	.expected_a_public_size = 256,
 	.expected_ss_size = 256,
+	},
+	{
+	.secret =
+#ifdef __LITTLE_ENDIAN
+	"\x01\x00" /* type */
+	"\x11\x01" /* len */
+	"\x00\x00\x00\x00" /* key_size */
+	"\x00\x01\x00\x00" /* p_size */
+	"\x01\x00\x00\x00" /* g_size */
+#else
+	"\x00\x01" /* type */
+	"\x01\x11" /* len */
+	"\x00\x00\x00\x00" /* key_size */
+	"\x00\x00\x01\x00" /* p_size */
+	"\x00\x00\x00\x01" /* g_size */
+#endif
+	/* p */
+	"\xb9\x36\x3a\xf1\x82\x1f\x60\xd3\x22\x47\xb8\xbc\x2d\x22\x6b\x81"
+	"\x7f\xe8\x20\x06\x09\x23\x73\x49\x9a\x59\x8b\x35\x25\xf8\x31\xbc"
+	"\x7d\xa8\x1c\x9d\x56\x0d\x1a\xf7\x4b\x4f\x96\xa4\x35\x77\x6a\x89"
+	"\xab\x42\x00\x49\x21\x71\xed\x28\x16\x1d\x87\x5a\x10\xa7\x9c\x64"
+	"\x94\xd4\x87\x3d\x28\xef\x44\xfe\x4b\xe2\xb4\x15\x8c\x82\xa6\xf3"
+	"\x50\x5f\xa8\xe8\xa2\x60\xe7\x00\x86\x78\x05\xd4\x78\x19\xa1\x98"
+	"\x62\x4e\x4a\x00\x78\x56\x96\xe6\xcf\xd7\x10\x1b\x74\x5d\xd0\x26"
+	"\x61\xdb\x6b\x32\x09\x51\xd8\xa5\xfd\x54\x16\x71\x01\xb3\x39\xe6"
+	"\x4e\x69\xb1\xd7\x06\x8f\xd6\x1e\xdc\x72\x25\x26\x74\xc8\x41\x06"
+	"\x5c\xd1\x26\x5c\xb0\x2f\xf9\x59\x13\xc1\x2a\x0f\x78\xea\x7b\xf7"
+	"\xbd\x59\xa0\x90\x1d\xfc\x33\x5b\x4c\xbf\x05\x9c\x3a\x3f\x69\xa2"
+	"\x45\x61\x4e\x10\x6a\xb3\x17\xc5\x68\x30\xfb\x07\x5f\x34\xc6\xfb"
+	"\x73\x07\x3c\x70\xf6\xae\xe7\x72\x84\xc3\x18\x81\x8f\xe8\x11\x1f"
+	"\x3d\x83\x83\x01\x2a\x14\x73\xbf\x32\x32\x2e\xc9\x4d\xdb\x2a\xca"
+	"\xee\x71\xf9\xda\xad\xe8\x82\x0b\x4d\x0c\x1f\xb6\x1d\xef\x00\x67"
+	"\x74\x3d\x95\xe0\xb7\xc4\x30\x8a\x24\x87\x12\x47\x27\x70\x0d\x73"
+	/* g */
+	"\x02",
+	.b_secret =
+#ifdef __LITTLE_ENDIAN
+	"\x01\x00" /* type */
+	"\x11\x02" /* len */
+	"\x00\x01\x00\x00" /* key_size */
+	"\x00\x01\x00\x00" /* p_size */
+	"\x01\x00\x00\x00" /* g_size */
+#else
+	"\x00\x01" /* type */
+	"\x02\x11" /* len */
+	"\x00\x00\x01\x00" /* key_size */
+	"\x00\x00\x01\x00" /* p_size */
+	"\x00\x00\x00\x01" /* g_size */
+#endif
+	/* xa */
+	"\x4d\x75\xa8\x6e\xba\x23\x3a\x0c\x63\x56\xc8\xc9\x5a\xa7\xd6\x0e"
+	"\xed\xae\x40\x78\x87\x47\x5f\xe0\xa7\x7b\xba\x84\x88\x67\x4e\xe5"
+	"\x3c\xcc\x5c\x6a\xe7\x4a\x20\xec\xbe\xcb\xf5\x52\x62\x9f\x37\x80"
+	"\x0c\x72\x7b\x83\x66\xa4\xf6\x7f\x95\x97\x1c\x6a\x5c\x7e\xf1\x67"
+	"\x37\xb3\x93\x39\x3d\x0b\x55\x35\xd9\xe5\x22\x04\x9f\xf8\xc1\x04"
+	"\xce\x13\xa5\xac\xe1\x75\x05\xd1\x2b\x53\xa2\x84\xef\xb1\x18\xf4"
+	"\x66\xdd\xea\xe6\x24\x69\x5a\x49\xe0\x7a\xd8\xdf\x1b\xb7\xf1\x6d"
+	"\x9b\x50\x2c\xc8\x1c\x1c\xa3\xb4\x37\xfb\x66\x3f\x67\x71\x73\xa9"
+	"\xff\x5f\xd9\xa2\x25\x6e\x25\x1b\x26\x54\xbf\x0c\xc6\xdb\xea\x0a"
+	"\x52\x6c\x16\x7c\x27\x68\x15\x71\x58\x73\x9d\xe6\xc2\x80\xaa\x97"
+	"\x31\x66\xfb\xa6\xfb\xfd\xd0\x9c\x1d\xbe\x81\x48\xf5\x9a\x32\xf1"
+	"\x69\x62\x18\x78\xae\x72\x36\xe6\x94\x27\xd1\xff\x18\x4f\x28\x6a"
+	"\x16\xbd\x6a\x60\xee\xe5\xf9\x6d\x16\xe4\xb8\xa6\x41\x9b\x23\x7e"
+	"\xf7\x9d\xd1\x1d\x03\x15\x66\x3a\xcf\xb6\x2c\x13\x96\x2c\x52\x21"
+	"\xe4\x2d\x48\x7a\x8a\x5d\xb2\x88\xed\x98\x61\x79\x8b\x6a\x1e\x5f"
+	"\xd0\x8a\x2d\x99\x5a\x2b\x0f\xbc\xef\x53\x8f\x32\xc1\xa2\x99\x26"
+	/* p */
+	"\xb9\x36\x3a\xf1\x82\x1f\x60\xd3\x22\x47\xb8\xbc\x2d\x22\x6b\x81"
+	"\x7f\xe8\x20\x06\x09\x23\x73\x49\x9a\x59\x8b\x35\x25\xf8\x31\xbc"
+	"\x7d\xa8\x1c\x9d\x56\x0d\x1a\xf7\x4b\x4f\x96\xa4\x35\x77\x6a\x89"
+	"\xab\x42\x00\x49\x21\x71\xed\x28\x16\x1d\x87\x5a\x10\xa7\x9c\x64"
+	"\x94\xd4\x87\x3d\x28\xef\x44\xfe\x4b\xe2\xb4\x15\x8c\x82\xa6\xf3"
+	"\x50\x5f\xa8\xe8\xa2\x60\xe7\x00\x86\x78\x05\xd4\x78\x19\xa1\x98"
+	"\x62\x4e\x4a\x00\x78\x56\x96\xe6\xcf\xd7\x10\x1b\x74\x5d\xd0\x26"
+	"\x61\xdb\x6b\x32\x09\x51\xd8\xa5\xfd\x54\x16\x71\x01\xb3\x39\xe6"
+	"\x4e\x69\xb1\xd7\x06\x8f\xd6\x1e\xdc\x72\x25\x26\x74\xc8\x41\x06"
+	"\x5c\xd1\x26\x5c\xb0\x2f\xf9\x59\x13\xc1\x2a\x0f\x78\xea\x7b\xf7"
+	"\xbd\x59\xa0\x90\x1d\xfc\x33\x5b\x4c\xbf\x05\x9c\x3a\x3f\x69\xa2"
+	"\x45\x61\x4e\x10\x6a\xb3\x17\xc5\x68\x30\xfb\x07\x5f\x34\xc6\xfb"
+	"\x73\x07\x3c\x70\xf6\xae\xe7\x72\x84\xc3\x18\x81\x8f\xe8\x11\x1f"
+	"\x3d\x83\x83\x01\x2a\x14\x73\xbf\x32\x32\x2e\xc9\x4d\xdb\x2a\xca"
+	"\xee\x71\xf9\xda\xad\xe8\x82\x0b\x4d\x0c\x1f\xb6\x1d\xef\x00\x67"
+	"\x74\x3d\x95\xe0\xb7\xc4\x30\x8a\x24\x87\x12\x47\x27\x70\x0d\x73"
+	/* g */
+	"\x02",
+	.b_public =
+	"\x90\x89\xe4\x82\xd6\x0a\xcf\x1a\xae\xce\x1b\x66\xa7\x19\x71\x18"
+	"\x8f\x95\x4b\x5b\x80\x45\x4a\x5a\x43\x99\x4d\x37\xcf\xa3\xa7\x28"
+	"\x9c\xc7\x73\xf1\xb2\x17\xf6\x99\xe3\x6b\x56\xcb\x3e\x35\x60\x7d"
+	"\x65\xc7\x84\x6b\x3e\x60\xee\xcd\xd2\x70\xe7\xc9\x32\x1c\xf0\xb4"
+	"\xf9\x52\xd9\x88\x75\xfd\x40\x2c\xa7\xbe\x19\x1c\x0a\xae\x93\xe1"
+	"\x71\xc7\xcd\x4f\x33\x5c\x10\x7d\x39\x56\xfc\x73\x84\xb2\x67\xc3"
+	"\x77\x26\x20\x97\x2b\xf8\x13\x43\x93\x9c\x9a\xa4\x08\xc7\x34\x83"
+	"\xe6\x98\x61\xe7\x16\x30\x2c\xb1\xdb\x2a\xb2\xcc\xc3\x02\xa5\x3c"
+	"\x71\x50\x14\x83\xc7\xbb\xa4\xbe\x98\x1b\xfe\xcb\x43\xe9\x97\x62"
+	"\xd6\xf0\x8c\xcb\x1c\xba\x1e\xa8\xa6\xa6\x50\xfc\x85\x7d\x47\xbf"
+	"\xf4\x3e\x23\xd3\x5f\xb2\x71\x3e\x40\x94\xaa\x87\x83\x2c\x6c\x8e"
+	"\x60\xfd\xdd\xf7\xf4\x76\x03\xd3\x1d\xec\x18\x51\xa3\xf2\x44\x1a"
+	"\x3f\xb4\x7c\x18\x0d\x68\x65\x92\x54\x0d\x2d\x81\x16\xf1\x84\x66"
+	"\x89\x92\xd0\x1a\x5e\x1f\x42\x46\x5b\xe5\x83\x86\x80\xd9\xcd\x3a"
+	"\x5a\x2f\xb9\x59\x9b\xe4\x43\x84\x64\xf3\x09\x1a\x0a\xa2\x64\x0f"
+	"\x77\x4e\x8d\x8b\xe6\x88\xd1\xfc\xaf\x8f\xdf\x1d\xbc\x31\xb3\xbd",
+	.secret_size = 273,
+	.b_secret_size = 529,
+	.b_public_size = 256,
+	.expected_a_public_size = 256,
+	.expected_ss_size = 256,
+	.genkey = true,
 	}
 };
 
@@ -840,6 +951,50 @@ static const struct kpp_testvec ecdh_tv_template[] = {
 	.b_public_size = 64,
 	.expected_a_public_size = 64,
 	.expected_ss_size = 32
+	}, {
+	.secret =
+#ifdef __LITTLE_ENDIAN
+	"\x02\x00" /* type */
+	"\x08\x00" /* len */
+	"\x02\x00" /* curve_id */
+	"\x00\x00", /* key_size */
+#else
+	"\x00\x02" /* type */
+	"\x00\x08" /* len */
+	"\x00\x02" /* curve_id */
+	"\x00\x00", /* key_size */
+#endif
+	.b_secret =
+#ifdef __LITTLE_ENDIAN
+	"\x02\x00" /* type */
+	"\x28\x00" /* len */
+	"\x02\x00" /* curve_id */
+	"\x20\x00" /* key_size */
+#else
+	"\x00\x02" /* type */
+	"\x00\x28" /* len */
+	"\x00\x02" /* curve_id */
+	"\x00\x20" /* key_size */
+#endif
+	"\x24\xd1\x21\xeb\xe5\xcf\x2d\x83"
+	"\xf6\x62\x1b\x6e\x43\x84\x3a\xa3"
+	"\x8b\xe0\x86\xc3\x20\x19\xda\x92"
+	"\x50\x53\x03\xe1\xc0\xea\xb8\x82",
+	.b_public =
+	"\x1a\x7f\xeb\x52\x00\xbd\x3c\x31"
+	"\x7d\xb6\x70\xc1\x86\xa6\xc7\xc4"
+	"\x3b\xc5\x5f\x6c\x6f\x58\x3c\xf5"
+	"\xb6\x63\x82\x77\x33\x24\xa1\x5f"
+	"\x6a\xca\x43\x6f\xf7\x7e\xff\x02"
+	"\x37\x08\xcc\x40\x5e\x7a\xfd\x6a"
+	"\x6a\x02\x6e\x41\x87\x68\x38\x77"
+	"\xfa\xa9\x44\x43\x2d\xef\x09\xdf",
+	.secret_size = 8,
+	.b_secret_size = 40,
+	.b_public_size = 64,
+	.expected_a_public_size = 64,
+	.expected_ss_size = 32,
+	.genkey = true,
 	}
 };
 
-- 
2.7.4

Re: [RFC PATCH v2 4/4] crypto: testmgr - add genkey kpp test

[Tudor Ambarus]

On 17.05.2017 18:26, Tudor Ambarus wrote:
> The test considers a party that already has a private-public
> key pair and a party that provides a NULL key. The kernel will
> generate the private-public key pair for the latter, computes
> the shared secret on both ends and verifies it it's the same.
> 
> The explicit private-public key pairs were copied from
> the previous test vectors.
> 
> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
> ---
>   crypto/testmgr.c |  76 +++++++++++++++++++++++----
>   crypto/testmgr.h | 155 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
>   2 files changed, 220 insertions(+), 11 deletions(-)
> 
> diff --git a/crypto/testmgr.c b/crypto/testmgr.c
> index 6f5f3ed..faf5fd8 100644
> --- a/crypto/testmgr.c
> +++ b/crypto/testmgr.c
> @@ -1997,6 +1997,9 @@ static int do_test_kpp(struct crypto_kpp *tfm, const struct kpp_testvec *vec,
>   	struct kpp_request *req;
>   	void *input_buf = NULL;
>   	void *output_buf = NULL;
> +	void *a_public = NULL;
> +	void *a_ss = NULL;
> +	void *shared_secret = NULL;
>   	struct tcrypt_result result;
>   	unsigned int out_len_max;
>   	int err = -ENOMEM;
> @@ -2026,20 +2029,31 @@ static int do_test_kpp(struct crypto_kpp *tfm, const struct kpp_testvec *vec,
>   	kpp_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
>   				 tcrypt_complete, &result);
>   
> -	/* Compute public key */
> +	/* Compute party A's public key */
>   	err = wait_async_op(&result, crypto_kpp_generate_public_key(req));
>   	if (err) {
> -		pr_err("alg: %s: generate public key test failed. err %d\n",
> +		pr_err("alg: %s: Party A: generate public key test failed. err %d\n",
>   		       alg, err);
>   		goto free_output;
>   	}
> -	/* Verify calculated public key */
> -	if (memcmp(vec->expected_a_public, sg_virt(req->dst),
> -		   vec->expected_a_public_size)) {
> -		pr_err("alg: %s: generate public key test failed. Invalid output\n",
> -		       alg);
> -		err = -EINVAL;
> -		goto free_output;
> +
> +	if (vec->genkey) {
> +		/* Save party A's public key */
> +		a_public = kzalloc(out_len_max, GFP_KERNEL);
> +		if (!a_public) {
> +			err = -ENOMEM;
> +			goto free_output;
> +		}
> +		memcpy(a_public, sg_virt(req->dst), sizeof(*a_public));

The size is wrong, I'll correct it in the next version.

Re: [RFC PATCH v2 1/4] crypto: ecc - add privkey generation support

[Stephan Müller]

Am Mittwoch, 17. Mai 2017, 17:26:50 CEST schrieb Tudor Ambarus:

Hi Tudor,

> Add support for generating ecc private keys.
> 
> Generation of ecc private keys is helpful in a user-space to kernel
> ecdh offload because the keys are not revealed to user-space. Private
> key generation is also helpful to implement forward secrecy.
> 
> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
> ---
>  crypto/ecc.c | 20 ++++++++++++++++++++
>  crypto/ecc.h | 14 ++++++++++++++
>  2 files changed, 34 insertions(+)
> 
> diff --git a/crypto/ecc.c b/crypto/ecc.c
> index 414c78a..a591907 100644
> --- a/crypto/ecc.c
> +++ b/crypto/ecc.c
> @@ -927,6 +927,26 @@ int ecc_is_key_valid(unsigned int curve_id, unsigned
> int ndigits, return 0;
>  }
> 
> +int ecc_gen_privkey(unsigned int curve_id, unsigned int ndigits, u64
> *privkey) +{
> +	const struct ecc_curve *curve = ecc_get_curve(curve_id);

Shouldn't there be a check that a curve is selected? I.e. a check for an error 
should be added?

> +	u64 priv[ndigits];

Shouldn't there be a size check of ndigits?

> +	unsigned int nbytes = ndigits << ECC_DIGITS_TO_BYTES_SHIFT;
> +
> +	get_random_bytes(priv, nbytes);

Can you please use crypto_get_default_rng / crypto_rng_get_bytes / 
crypto_put_default_rng?
> +
> +	if (vli_is_zero(priv, ndigits))
> +		return -EINVAL;
> +
> +	/* Make sure the private key is in the range [1, n-1]. */
> +	if (vli_cmp(curve->n, priv, ndigits) != 1)
> +		return -EINVAL;
> +
> +	ecc_swap_digits(priv, privkey, ndigits);

Is a byteswap faster than a copy operation by looping through priv/privkey and 
simply assinging the value?
> +
> +	return 0;
> +}
> +
>  int ecdh_make_pub_key(unsigned int curve_id, unsigned int ndigits,
>  		      const u8 *private_key, unsigned int private_key_len,
>  		      u8 *public_key, unsigned int public_key_len)
> diff --git a/crypto/ecc.h b/crypto/ecc.h
> index 663d598..b94b7ce 100644
> --- a/crypto/ecc.h
> +++ b/crypto/ecc.h
> @@ -44,6 +44,20 @@ int ecc_is_key_valid(unsigned int curve_id, unsigned int
> ndigits, const u8 *private_key, unsigned int private_key_len);
> 
>  /**
> + * ecc_gen_privkey() -  Generates an ECC private key.
> + * The private key is a random integer in the range 0 < random < n, where n
> is a + * prime that is the order of the cyclic subgroup generated by the
> distinguished + * point G.
> + * @curve_id:		id representing the curve to use
> + * @ndigits:		curve number of digits
> + * @private_key:	buffer for storing the generated private key
> + *
> + * Returns 0 if the private key was generated successfully, a negative
> value + * if an error occurred.
> + */
> +int ecc_gen_privkey(unsigned int curve_id, unsigned int ndigits, u64
> *privkey); +
> +/**
>   * ecdh_make_pub_key() - Compute an ECC public key
>   *
>   * @curve_id:		id representing the curve to use


Ciao
Stephan

Re: [RFC PATCH v2 3/4] crypto: dh - allow user to provide NULL privkey

[Stephan Müller]

Am Mittwoch, 17. Mai 2017, 17:26:52 CEST schrieb Tudor Ambarus:

Hi Tudor,

> If the user provides a NULL private key, the kernel will
> generate it and further use it for dh.
> 
> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
> ---
>  crypto/dh.c | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
> 
> diff --git a/crypto/dh.c b/crypto/dh.c
> index 87e3542..7b4ac5b 100644
> --- a/crypto/dh.c
> +++ b/crypto/dh.c
> @@ -83,7 +83,9 @@ static int dh_set_secret(struct crypto_kpp *tfm, const
> void *buf, unsigned int len)
>  {
>  	struct dh_ctx *ctx = dh_get_ctx(tfm);
> +	u8 *rndbuf = NULL;
>  	struct dh params;
> +	int maxsize;
> 
>  	if (crypto_dh_decode_key(buf, len, &params) < 0)
>  		return -EINVAL;
> @@ -91,7 +93,26 @@ static int dh_set_secret(struct crypto_kpp *tfm, const
> void *buf, if (dh_set_params(ctx, &params) < 0)
>  		return -EINVAL;
> 
> +	if (!params.key || !params.key_size) {
> +		maxsize = crypto_kpp_maxsize(tfm);
> +		if (maxsize < 0) {
> +			dh_clear_params(ctx);
> +			return maxsize;
> +		}
> +
> +		rndbuf = kmalloc(maxsize, GFP_KERNEL);
> +		if (!rndbuf) {
> +			dh_clear_params(ctx);
> +			return -ENOMEM;
> +		}
> +
> +		get_random_bytes(rndbuf, maxsize);

Could you please use again the kernel crypto API RNG as mentioned for ECC?


> +		params.key = rndbuf;
> +		params.key_size = maxsize;
> +	}
> +
>  	ctx->xa = mpi_read_raw_data(params.key, params.key_size);
> +	kzfree(rndbuf);
>  	if (!ctx->xa) {
>  		dh_clear_params(ctx);
>  		return -EINVAL;


Ciao
Stephan

Re: [RFC PATCH v2 4/4] crypto: testmgr - add genkey kpp test

[Stephan Müller]

Am Mittwoch, 17. Mai 2017, 17:26:53 CEST schrieb Tudor Ambarus:

Hi Tudor,

> The test considers a party that already has a private-public
> key pair and a party that provides a NULL key. The kernel will
> generate the private-public key pair for the latter, computes
> the shared secret on both ends and verifies it it's the same.
> 
> The explicit private-public key pairs were copied from
> the previous test vectors.
> 
> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
> ---
>  crypto/testmgr.c |  76 +++++++++++++++++++++++----
>  crypto/testmgr.h | 155
> +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed,
> 220 insertions(+), 11 deletions(-)
> 
> diff --git a/crypto/testmgr.c b/crypto/testmgr.c
> index 6f5f3ed..faf5fd8 100644
> --- a/crypto/testmgr.c
> +++ b/crypto/testmgr.c
> @@ -1997,6 +1997,9 @@ static int do_test_kpp(struct crypto_kpp *tfm, const
> struct kpp_testvec *vec, struct kpp_request *req;
>  	void *input_buf = NULL;
>  	void *output_buf = NULL;
> +	void *a_public = NULL;
> +	void *a_ss = NULL;
> +	void *shared_secret = NULL;
>  	struct tcrypt_result result;
>  	unsigned int out_len_max;
>  	int err = -ENOMEM;
> @@ -2026,20 +2029,31 @@ static int do_test_kpp(struct crypto_kpp *tfm, const
> struct kpp_testvec *vec, kpp_request_set_callback(req,
> CRYPTO_TFM_REQ_MAY_BACKLOG,
>  				 tcrypt_complete, &result);
> 
> -	/* Compute public key */
> +	/* Compute party A's public key */
>  	err = wait_async_op(&result, crypto_kpp_generate_public_key(req));
>  	if (err) {
> -		pr_err("alg: %s: generate public key test failed. err %d\n",
> +		pr_err("alg: %s: Party A: generate public key test failed. err %d\n",
>  		       alg, err);
>  		goto free_output;
>  	}
> -	/* Verify calculated public key */
> -	if (memcmp(vec->expected_a_public, sg_virt(req->dst),
> -		   vec->expected_a_public_size)) {
> -		pr_err("alg: %s: generate public key test failed. Invalid output\n",
> -		       alg);
> -		err = -EINVAL;
> -		goto free_output;
> +
> +	if (vec->genkey) {
> +		/* Save party A's public key */
> +		a_public = kzalloc(out_len_max, GFP_KERNEL);
> +		if (!a_public) {
> +			err = -ENOMEM;
> +			goto free_output;
> +		}
> +		memcpy(a_public, sg_virt(req->dst), sizeof(*a_public));

As you mentioned, sizeof() may not be the right length.

> +	} else {
> +		/* Verify calculated public key */
> +		if (memcmp(vec->expected_a_public, sg_virt(req->dst),
> +			   vec->expected_a_public_size)) {
> +			pr_err("alg: %s: Party A: generate public key test failed. Invalid
> output\n", +			       alg);
> +			err = -EINVAL;
> +			goto free_output;
> +		}
>  	}
> 
>  	/* Calculate shared secret key by using counter part (b) public key. */
> @@ -2058,15 +2072,53 @@ static int do_test_kpp(struct crypto_kpp *tfm, const
> struct kpp_testvec *vec, tcrypt_complete, &result);
>  	err = wait_async_op(&result, crypto_kpp_compute_shared_secret(req));
>  	if (err) {
> -		pr_err("alg: %s: compute shard secret test failed. err %d\n",
> +		pr_err("alg: %s: Party A: compute shared secret test failed. err %d
\n",
>  		       alg, err);
>  		goto free_all;
>  	}
> +
> +	if (vec->genkey) {
> +		/* Save the shared secret obtained by party A */
> +		a_ss = kzalloc(vec->expected_ss_size, GFP_KERNEL);
> +		if (!a_ss) {
> +			err = -ENOMEM;
> +			goto free_all;
> +		}
> +		memcpy(a_ss, sg_virt(req->dst), sizeof(*a_ss));

Same here, sizeof(void *)?
> +
> +		/*
> +		 * Calculate party B's shared secret by using party A's
> +		 * public key.
> +		 */
> +		err = crypto_kpp_set_secret(tfm, vec->b_secret,
> +					    vec->b_secret_size);
> +		if (err < 0)
> +			goto free_all;
> +
> +		sg_init_one(&src, a_public, vec->expected_a_public_size);
> +		sg_init_one(&dst, output_buf, out_len_max);
> +		kpp_request_set_input(req, &src, vec->expected_a_public_size);
> +		kpp_request_set_output(req, &dst, out_len_max);
> +		kpp_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
> +					 tcrypt_complete, &result);
> +		err = wait_async_op(&result,
> +				    crypto_kpp_compute_shared_secret(req));
> +		if (err) {
> +			pr_err("alg: %s: Party B: compute shared secret failed. err %d\n",
> +			       alg, err);
> +			goto free_all;
> +		}
> +
> +		shared_secret = a_ss;
> +	} else {
> +		shared_secret = (void *)vec->expected_ss;
> +	}
> +
>  	/*
>  	 * verify shared secret from which the user will derive
>  	 * secret key by executing whatever hash it has chosen
>  	 */
> -	if (memcmp(vec->expected_ss, sg_virt(req->dst),
> +	if (memcmp(shared_secret, sg_virt(req->dst),
>  		   vec->expected_ss_size)) {
>  		pr_err("alg: %s: compute shared secret test failed. Invalid output\n",
>  		       alg);
> @@ -2074,8 +2126,10 @@ static int do_test_kpp(struct crypto_kpp *tfm, const
> struct kpp_testvec *vec, }
> 
>  free_all:
> +	kfree(a_ss);
>  	kfree(input_buf);
>  free_output:
> +	kfree(a_public);
>  	kfree(output_buf);
>  free_req:
>  	kpp_request_free(req);
> diff --git a/crypto/testmgr.h b/crypto/testmgr.h
> index 4293573..a6c6b24 100644
> --- a/crypto/testmgr.h
> +++ b/crypto/testmgr.h
> @@ -137,13 +137,16 @@ struct akcipher_testvec {
> 
>  struct kpp_testvec {
>  	const unsigned char *secret;
> +	const unsigned char *b_secret;
>  	const unsigned char *b_public;
>  	const unsigned char *expected_a_public;
>  	const unsigned char *expected_ss;
>  	unsigned short secret_size;
> +	unsigned short b_secret_size;
>  	unsigned short b_public_size;
>  	unsigned short expected_a_public_size;
>  	unsigned short expected_ss_size;
> +	bool genkey;
>  };
> 
>  static const char zeroed_string[48];
> @@ -752,6 +755,114 @@ static const struct kpp_testvec dh_tv_template[] = {
>  	.b_public_size = 256,
>  	.expected_a_public_size = 256,
>  	.expected_ss_size = 256,
> +	},
> +	{
> +	.secret =
> +#ifdef __LITTLE_ENDIAN
> +	"\x01\x00" /* type */
> +	"\x11\x01" /* len */
> +	"\x00\x00\x00\x00" /* key_size */
> +	"\x00\x01\x00\x00" /* p_size */
> +	"\x01\x00\x00\x00" /* g_size */
> +#else
> +	"\x00\x01" /* type */
> +	"\x01\x11" /* len */
> +	"\x00\x00\x00\x00" /* key_size */
> +	"\x00\x00\x01\x00" /* p_size */
> +	"\x00\x00\x00\x01" /* g_size */
> +#endif
> +	/* p */
> +	"\xb9\x36\x3a\xf1\x82\x1f\x60\xd3\x22\x47\xb8\xbc\x2d\x22\x6b\x81"
> +	"\x7f\xe8\x20\x06\x09\x23\x73\x49\x9a\x59\x8b\x35\x25\xf8\x31\xbc"
> +	"\x7d\xa8\x1c\x9d\x56\x0d\x1a\xf7\x4b\x4f\x96\xa4\x35\x77\x6a\x89"
> +	"\xab\x42\x00\x49\x21\x71\xed\x28\x16\x1d\x87\x5a\x10\xa7\x9c\x64"
> +	"\x94\xd4\x87\x3d\x28\xef\x44\xfe\x4b\xe2\xb4\x15\x8c\x82\xa6\xf3"
> +	"\x50\x5f\xa8\xe8\xa2\x60\xe7\x00\x86\x78\x05\xd4\x78\x19\xa1\x98"
> +	"\x62\x4e\x4a\x00\x78\x56\x96\xe6\xcf\xd7\x10\x1b\x74\x5d\xd0\x26"
> +	"\x61\xdb\x6b\x32\x09\x51\xd8\xa5\xfd\x54\x16\x71\x01\xb3\x39\xe6"
> +	"\x4e\x69\xb1\xd7\x06\x8f\xd6\x1e\xdc\x72\x25\x26\x74\xc8\x41\x06"
> +	"\x5c\xd1\x26\x5c\xb0\x2f\xf9\x59\x13\xc1\x2a\x0f\x78\xea\x7b\xf7"
> +	"\xbd\x59\xa0\x90\x1d\xfc\x33\x5b\x4c\xbf\x05\x9c\x3a\x3f\x69\xa2"
> +	"\x45\x61\x4e\x10\x6a\xb3\x17\xc5\x68\x30\xfb\x07\x5f\x34\xc6\xfb"
> +	"\x73\x07\x3c\x70\xf6\xae\xe7\x72\x84\xc3\x18\x81\x8f\xe8\x11\x1f"
> +	"\x3d\x83\x83\x01\x2a\x14\x73\xbf\x32\x32\x2e\xc9\x4d\xdb\x2a\xca"
> +	"\xee\x71\xf9\xda\xad\xe8\x82\x0b\x4d\x0c\x1f\xb6\x1d\xef\x00\x67"
> +	"\x74\x3d\x95\xe0\xb7\xc4\x30\x8a\x24\x87\x12\x47\x27\x70\x0d\x73"
> +	/* g */
> +	"\x02",
> +	.b_secret =
> +#ifdef __LITTLE_ENDIAN
> +	"\x01\x00" /* type */
> +	"\x11\x02" /* len */
> +	"\x00\x01\x00\x00" /* key_size */
> +	"\x00\x01\x00\x00" /* p_size */
> +	"\x01\x00\x00\x00" /* g_size */
> +#else
> +	"\x00\x01" /* type */
> +	"\x02\x11" /* len */
> +	"\x00\x00\x01\x00" /* key_size */
> +	"\x00\x00\x01\x00" /* p_size */
> +	"\x00\x00\x00\x01" /* g_size */
> +#endif
> +	/* xa */
> +	"\x4d\x75\xa8\x6e\xba\x23\x3a\x0c\x63\x56\xc8\xc9\x5a\xa7\xd6\x0e"
> +	"\xed\xae\x40\x78\x87\x47\x5f\xe0\xa7\x7b\xba\x84\x88\x67\x4e\xe5"
> +	"\x3c\xcc\x5c\x6a\xe7\x4a\x20\xec\xbe\xcb\xf5\x52\x62\x9f\x37\x80"
> +	"\x0c\x72\x7b\x83\x66\xa4\xf6\x7f\x95\x97\x1c\x6a\x5c\x7e\xf1\x67"
> +	"\x37\xb3\x93\x39\x3d\x0b\x55\x35\xd9\xe5\x22\x04\x9f\xf8\xc1\x04"
> +	"\xce\x13\xa5\xac\xe1\x75\x05\xd1\x2b\x53\xa2\x84\xef\xb1\x18\xf4"
> +	"\x66\xdd\xea\xe6\x24\x69\x5a\x49\xe0\x7a\xd8\xdf\x1b\xb7\xf1\x6d"
> +	"\x9b\x50\x2c\xc8\x1c\x1c\xa3\xb4\x37\xfb\x66\x3f\x67\x71\x73\xa9"
> +	"\xff\x5f\xd9\xa2\x25\x6e\x25\x1b\x26\x54\xbf\x0c\xc6\xdb\xea\x0a"
> +	"\x52\x6c\x16\x7c\x27\x68\x15\x71\x58\x73\x9d\xe6\xc2\x80\xaa\x97"
> +	"\x31\x66\xfb\xa6\xfb\xfd\xd0\x9c\x1d\xbe\x81\x48\xf5\x9a\x32\xf1"
> +	"\x69\x62\x18\x78\xae\x72\x36\xe6\x94\x27\xd1\xff\x18\x4f\x28\x6a"
> +	"\x16\xbd\x6a\x60\xee\xe5\xf9\x6d\x16\xe4\xb8\xa6\x41\x9b\x23\x7e"
> +	"\xf7\x9d\xd1\x1d\x03\x15\x66\x3a\xcf\xb6\x2c\x13\x96\x2c\x52\x21"
> +	"\xe4\x2d\x48\x7a\x8a\x5d\xb2\x88\xed\x98\x61\x79\x8b\x6a\x1e\x5f"
> +	"\xd0\x8a\x2d\x99\x5a\x2b\x0f\xbc\xef\x53\x8f\x32\xc1\xa2\x99\x26"
> +	/* p */
> +	"\xb9\x36\x3a\xf1\x82\x1f\x60\xd3\x22\x47\xb8\xbc\x2d\x22\x6b\x81"
> +	"\x7f\xe8\x20\x06\x09\x23\x73\x49\x9a\x59\x8b\x35\x25\xf8\x31\xbc"
> +	"\x7d\xa8\x1c\x9d\x56\x0d\x1a\xf7\x4b\x4f\x96\xa4\x35\x77\x6a\x89"
> +	"\xab\x42\x00\x49\x21\x71\xed\x28\x16\x1d\x87\x5a\x10\xa7\x9c\x64"
> +	"\x94\xd4\x87\x3d\x28\xef\x44\xfe\x4b\xe2\xb4\x15\x8c\x82\xa6\xf3"
> +	"\x50\x5f\xa8\xe8\xa2\x60\xe7\x00\x86\x78\x05\xd4\x78\x19\xa1\x98"
> +	"\x62\x4e\x4a\x00\x78\x56\x96\xe6\xcf\xd7\x10\x1b\x74\x5d\xd0\x26"
> +	"\x61\xdb\x6b\x32\x09\x51\xd8\xa5\xfd\x54\x16\x71\x01\xb3\x39\xe6"
> +	"\x4e\x69\xb1\xd7\x06\x8f\xd6\x1e\xdc\x72\x25\x26\x74\xc8\x41\x06"
> +	"\x5c\xd1\x26\x5c\xb0\x2f\xf9\x59\x13\xc1\x2a\x0f\x78\xea\x7b\xf7"
> +	"\xbd\x59\xa0\x90\x1d\xfc\x33\x5b\x4c\xbf\x05\x9c\x3a\x3f\x69\xa2"
> +	"\x45\x61\x4e\x10\x6a\xb3\x17\xc5\x68\x30\xfb\x07\x5f\x34\xc6\xfb"
> +	"\x73\x07\x3c\x70\xf6\xae\xe7\x72\x84\xc3\x18\x81\x8f\xe8\x11\x1f"
> +	"\x3d\x83\x83\x01\x2a\x14\x73\xbf\x32\x32\x2e\xc9\x4d\xdb\x2a\xca"
> +	"\xee\x71\xf9\xda\xad\xe8\x82\x0b\x4d\x0c\x1f\xb6\x1d\xef\x00\x67"
> +	"\x74\x3d\x95\xe0\xb7\xc4\x30\x8a\x24\x87\x12\x47\x27\x70\x0d\x73"
> +	/* g */
> +	"\x02",
> +	.b_public =
> +	"\x90\x89\xe4\x82\xd6\x0a\xcf\x1a\xae\xce\x1b\x66\xa7\x19\x71\x18"
> +	"\x8f\x95\x4b\x5b\x80\x45\x4a\x5a\x43\x99\x4d\x37\xcf\xa3\xa7\x28"
> +	"\x9c\xc7\x73\xf1\xb2\x17\xf6\x99\xe3\x6b\x56\xcb\x3e\x35\x60\x7d"
> +	"\x65\xc7\x84\x6b\x3e\x60\xee\xcd\xd2\x70\xe7\xc9\x32\x1c\xf0\xb4"
> +	"\xf9\x52\xd9\x88\x75\xfd\x40\x2c\xa7\xbe\x19\x1c\x0a\xae\x93\xe1"
> +	"\x71\xc7\xcd\x4f\x33\x5c\x10\x7d\x39\x56\xfc\x73\x84\xb2\x67\xc3"
> +	"\x77\x26\x20\x97\x2b\xf8\x13\x43\x93\x9c\x9a\xa4\x08\xc7\x34\x83"
> +	"\xe6\x98\x61\xe7\x16\x30\x2c\xb1\xdb\x2a\xb2\xcc\xc3\x02\xa5\x3c"
> +	"\x71\x50\x14\x83\xc7\xbb\xa4\xbe\x98\x1b\xfe\xcb\x43\xe9\x97\x62"
> +	"\xd6\xf0\x8c\xcb\x1c\xba\x1e\xa8\xa6\xa6\x50\xfc\x85\x7d\x47\xbf"
> +	"\xf4\x3e\x23\xd3\x5f\xb2\x71\x3e\x40\x94\xaa\x87\x83\x2c\x6c\x8e"
> +	"\x60\xfd\xdd\xf7\xf4\x76\x03\xd3\x1d\xec\x18\x51\xa3\xf2\x44\x1a"
> +	"\x3f\xb4\x7c\x18\x0d\x68\x65\x92\x54\x0d\x2d\x81\x16\xf1\x84\x66"
> +	"\x89\x92\xd0\x1a\x5e\x1f\x42\x46\x5b\xe5\x83\x86\x80\xd9\xcd\x3a"
> +	"\x5a\x2f\xb9\x59\x9b\xe4\x43\x84\x64\xf3\x09\x1a\x0a\xa2\x64\x0f"
> +	"\x77\x4e\x8d\x8b\xe6\x88\xd1\xfc\xaf\x8f\xdf\x1d\xbc\x31\xb3\xbd",
> +	.secret_size = 273,
> +	.b_secret_size = 529,
> +	.b_public_size = 256,
> +	.expected_a_public_size = 256,
> +	.expected_ss_size = 256,
> +	.genkey = true,
>  	}
>  };
> 
> @@ -840,6 +951,50 @@ static const struct kpp_testvec ecdh_tv_template[] = {
>  	.b_public_size = 64,
>  	.expected_a_public_size = 64,
>  	.expected_ss_size = 32
> +	}, {
> +	.secret =
> +#ifdef __LITTLE_ENDIAN
> +	"\x02\x00" /* type */
> +	"\x08\x00" /* len */
> +	"\x02\x00" /* curve_id */
> +	"\x00\x00", /* key_size */
> +#else
> +	"\x00\x02" /* type */
> +	"\x00\x08" /* len */
> +	"\x00\x02" /* curve_id */
> +	"\x00\x00", /* key_size */
> +#endif
> +	.b_secret =
> +#ifdef __LITTLE_ENDIAN
> +	"\x02\x00" /* type */
> +	"\x28\x00" /* len */
> +	"\x02\x00" /* curve_id */
> +	"\x20\x00" /* key_size */
> +#else
> +	"\x00\x02" /* type */
> +	"\x00\x28" /* len */
> +	"\x00\x02" /* curve_id */
> +	"\x00\x20" /* key_size */
> +#endif
> +	"\x24\xd1\x21\xeb\xe5\xcf\x2d\x83"
> +	"\xf6\x62\x1b\x6e\x43\x84\x3a\xa3"
> +	"\x8b\xe0\x86\xc3\x20\x19\xda\x92"
> +	"\x50\x53\x03\xe1\xc0\xea\xb8\x82",
> +	.b_public =
> +	"\x1a\x7f\xeb\x52\x00\xbd\x3c\x31"
> +	"\x7d\xb6\x70\xc1\x86\xa6\xc7\xc4"
> +	"\x3b\xc5\x5f\x6c\x6f\x58\x3c\xf5"
> +	"\xb6\x63\x82\x77\x33\x24\xa1\x5f"
> +	"\x6a\xca\x43\x6f\xf7\x7e\xff\x02"
> +	"\x37\x08\xcc\x40\x5e\x7a\xfd\x6a"
> +	"\x6a\x02\x6e\x41\x87\x68\x38\x77"
> +	"\xfa\xa9\x44\x43\x2d\xef\x09\xdf",
> +	.secret_size = 8,
> +	.b_secret_size = 40,
> +	.b_public_size = 64,
> +	.expected_a_public_size = 64,
> +	.expected_ss_size = 32,
> +	.genkey = true,
>  	}
>  };


Ciao
Stephan

Re: [RFC PATCH v2 1/4] crypto: ecc - add privkey generation support

[Tudor Ambarus]

Hi, Stephan,

Thank you for the review. Please see inline.

On 28.05.2017 21:44, Stephan Müller wrote:
> Am Mittwoch, 17. Mai 2017, 17:26:50 CEST schrieb Tudor Ambarus:
> 
> Hi Tudor,
> 
>> Add support for generating ecc private keys.
>>
>> Generation of ecc private keys is helpful in a user-space to kernel
>> ecdh offload because the keys are not revealed to user-space. Private
>> key generation is also helpful to implement forward secrecy.
>>
>> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
>> ---
>>   crypto/ecc.c | 20 ++++++++++++++++++++
>>   crypto/ecc.h | 14 ++++++++++++++
>>   2 files changed, 34 insertions(+)
>>
>> diff --git a/crypto/ecc.c b/crypto/ecc.c
>> index 414c78a..a591907 100644
>> --- a/crypto/ecc.c
>> +++ b/crypto/ecc.c
>> @@ -927,6 +927,26 @@ int ecc_is_key_valid(unsigned int curve_id, unsigned
>> int ndigits, return 0;
>>   }
>>
>> +int ecc_gen_privkey(unsigned int curve_id, unsigned int ndigits, u64
>> *privkey) +{
>> +	const struct ecc_curve *curve = ecc_get_curve(curve_id);
> 
> Shouldn't there be a check that a curve is selected? I.e. a check for an error
> should be added?

We already checked the curve_id before generating the key. The function
assumes that curve_id is checked before calling it, like 
ecc_is_key_valid() does.

> 
>> +	u64 priv[ndigits];
> 
> Shouldn't there be a size check of ndigits?

Already checked when setting the secret. But FIPS 186-4, B.4.1
recommends to check the bit length of n. It should be greater or equal 
with 160. I will add this check, thanks.

> 
>> +	unsigned int nbytes = ndigits << ECC_DIGITS_TO_BYTES_SHIFT;
>> +
>> +	get_random_bytes(priv, nbytes);
> 
> Can you please use crypto_get_default_rng / crypto_rng_get_bytes /
> crypto_put_default_rng?

Actually I tried this and I encountered some problems, I'm currently
debugging it.

When using the default rng and the run-time self tests are enabled,
the kernel is in a blocking state. What's worse is that the kernel
blocks before the console has the chance to be enabled and I can't see
anything :).

I suspect that the kernel blocks because the rng does not have enough
entropy. Could you please give me some hints?

>> +
>> +	if (vli_is_zero(priv, ndigits))
>> +		return -EINVAL;
>> +
>> +	/* Make sure the private key is in the range [1, n-1]. */
>> +	if (vli_cmp(curve->n, priv, ndigits) != 1)
>> +		return -EINVAL;
>> +
>> +	ecc_swap_digits(priv, privkey, ndigits);
> 
> Is a byteswap faster than a copy operation by looping through priv/privkey and
> simply assinging the value?

Maybe not, but I am consistent with the rest of the code. Can we change
this in a latter patch, if necessary?

Thanks,
ta

Re: [RFC PATCH v2 1/4] crypto: ecc - add privkey generation support

[Stephan Müller]

Am Montag, 29. Mai 2017, 11:08:38 CEST schrieb Tudor Ambarus:

Hi Tudor,
> 
> >> +	unsigned int nbytes = ndigits << ECC_DIGITS_TO_BYTES_SHIFT;
> >> +
> >> +	get_random_bytes(priv, nbytes);
> > 
> > Can you please use crypto_get_default_rng / crypto_rng_get_bytes /
> > crypto_put_default_rng?
> 
> Actually I tried this and I encountered some problems, I'm currently
> debugging it.
> 
> When using the default rng and the run-time self tests are enabled,
> the kernel is in a blocking state. What's worse is that the kernel
> blocks before the console has the chance to be enabled and I can't see
> anything :).
> 
> I suspect that the kernel blocks because the rng does not have enough
> entropy. Could you please give me some hints?

Hm, there should be no blocking for the DRBG to initialize.

What happens if you compile that as a module and insmod it at runtime?
> 
> >> +
> >> +	if (vli_is_zero(priv, ndigits))
> >> +		return -EINVAL;
> >> +
> >> +	/* Make sure the private key is in the range [1, n-1]. */
> >> +	if (vli_cmp(curve->n, priv, ndigits) != 1)
> >> +		return -EINVAL;
> >> +
> >> +	ecc_swap_digits(priv, privkey, ndigits);
> > 
> > Is a byteswap faster than a copy operation by looping through priv/privkey
> > and simply assinging the value?
> 
> Maybe not, but I am consistent with the rest of the code. Can we change
> this in a latter patch, if necessary?

Ok, fine with me.


Ciao
Stephan

Re: [RFC PATCH v2 1/4] crypto: ecc - add privkey generation support

[Tudor Ambarus]

Hi, Stephan,

On 29.05.2017 12:23, Stephan Müller wrote:
> Am Montag, 29. Mai 2017, 11:08:38 CEST schrieb Tudor Ambarus:
> 
> Hi Tudor,
>>
>>>> +	unsigned int nbytes = ndigits << ECC_DIGITS_TO_BYTES_SHIFT;
>>>> +
>>>> +	get_random_bytes(priv, nbytes);
>>>
>>> Can you please use crypto_get_default_rng / crypto_rng_get_bytes /
>>> crypto_put_default_rng?
>>
>> Actually I tried this and I encountered some problems, I'm currently
>> debugging it.
>>
>> When using the default rng and the run-time self tests are enabled,
>> the kernel is in a blocking state. What's worse is that the kernel
>> blocks before the console has the chance to be enabled and I can't see
>> anything :).
>>
>> I suspect that the kernel blocks because the rng does not have enough
>> entropy. Could you please give me some hints?
> 
> Hm, there should be no blocking for the DRBG to initialize.
> 
> What happens if you compile that as a module and insmod it at runtime?

We will have a nop:

#ifdef CONFIG_CRYPTO_MANAGER_DISABLE_TESTS

/* a perfect nop */
int alg_test(const char *driver, const char *alg, u32 type, u32 mask)
{
	printk(KERN_ERR "no op in alg_test");
	return 0;
}

#else
...
#endif

If I further mangle it and change #ifdef with #ifndef then the tests are
passing.

Thanks,
ta

Re: [RFC PATCH v2 1/4] crypto: ecc - add privkey generation support

[Stephan Müller]

Am Montag, 29. Mai 2017, 11:47:48 CEST schrieb Tudor Ambarus:

Hi Tudor,

> > Hm, there should be no blocking for the DRBG to initialize.
> > 
> > What happens if you compile that as a module and insmod it at runtime?
> 
> We will have a nop:
> 
> #ifdef CONFIG_CRYPTO_MANAGER_DISABLE_TESTS
> 
> /* a perfect nop */
> int alg_test(const char *driver, const char *alg, u32 type, u32 mask)
> {
> 	printk(KERN_ERR "no op in alg_test");
> 	return 0;
> }
> 
> #else
> ...
> #endif
> 
> If I further mangle it and change #ifdef with #ifndef then the tests are
> passing.

Can you please enable the testmgr in the kernel config and compile the DH/ECDH 
code as a module. Then I would insmod the dh/ecdh kernel module to see whether 
the self tests work or not.

Note, if you use the calls of crypto_get_default_rng and friends, the DRBG 
must be present in the kernel at the time of calling. I.e. if you statically 
compile dh/ecdh but compile the RNG support as a module, the RNG will not load 
during self test. If you compile dh/ecdh as a module, the RNG can stay as a 
module.

Ciao
Stephan

Re: [RFC PATCH v2 1/4] crypto: ecc - add privkey generation support

[Tudor Ambarus]

Hi, Stephan,

On 29.05.2017 12:56, Stephan Müller wrote:
> Am Montag, 29. Mai 2017, 11:47:48 CEST schrieb Tudor Ambarus:
> 
> Hi Tudor,
> 
>>> Hm, there should be no blocking for the DRBG to initialize.
>>>
>>> What happens if you compile that as a module and insmod it at runtime?
>>
>> We will have a nop:
>>
>> #ifdef CONFIG_CRYPTO_MANAGER_DISABLE_TESTS
>>
>> /* a perfect nop */
>> int alg_test(const char *driver, const char *alg, u32 type, u32 mask)
>> {
>> 	printk(KERN_ERR "no op in alg_test");
>> 	return 0;
>> }
>>
>> #else
>> ...
>> #endif
>>
>> If I further mangle it and change #ifdef with #ifndef then the tests are
>> passing.
> 
> Can you please enable the testmgr in the kernel config and compile the DH/ECDH
> code as a module. Then I would insmod the dh/ecdh kernel module to see whether
> the self tests work or not.

dh/ecdh self tests are passing when I insert dh/ecdh modules.

> 
> Note, if you use the calls of crypto_get_default_rng and friends, the DRBG
> must be present in the kernel at the time of calling. I.e. if you statically
> compile dh/ecdh but compile the RNG support as a module, the RNG will not load
> during self test. If you compile dh/ecdh as a module, the RNG can stay as a
> module.

However, when the self tests are enabled and DH/ECDH code is built-in, 
the kernel blocks.

I have to ensure that the drivers are loaded in the right order. 
Deferring the probe or just simply changing the order of the object
files from crypto/Makefile solves the issue. I'll go with the second
approach.

Thanks,
ta