[PATCH v3 2/2] crypto: testmgr - add genkey kpp test

[Tudor Ambarus <tudor.ambarus@microchip.com>]

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 if it's the same.

The explicit private-public key pair was copied from
the previous test vector.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
---
 crypto/testmgr.c | 76 ++++++++++++++++++++++++++++++++++++++++++++++++--------
 crypto/testmgr.h | 47 +++++++++++++++++++++++++++++++++++
 2 files changed, 112 insertions(+), 11 deletions(-)

diff --git a/crypto/testmgr.c b/crypto/testmgr.c
index 6f5f3ed..5f8e683 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), out_len_max);
+	} 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), vec->expected_ss_size);
+
+		/*
+		 * 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..db2e26c 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];
@@ -840,6 +843,50 @@ 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