2 files changed, 261 insertions, 73 deletions

diff --git a/crypto/testmgr.c b/crypto/testmgr.c
index 4fe210845e78..88f33c0efb23 100644
--- a/crypto/testmgr.c
+++ b/crypto/testmgr.c
@@ -82,6 +82,19 @@ int alg_test(const char *driver, const char *alg, u32 type, u32 mask)
 struct aead_test_suite {
 	const struct aead_testvec *vecs;
 	unsigned int count;
+
+	/*
+	 * Set if trying to decrypt an inauthentic ciphertext with this
+	 * algorithm might result in EINVAL rather than EBADMSG, due to other
+	 * validation the algorithm does on the inputs such as length checks.
+	 */
+	unsigned int einval_allowed : 1;
+
+	/*
+	 * Set if the algorithm intentionally ignores the last 8 bytes of the
+	 * AAD buffer during decryption.
+	 */
+	unsigned int esp_aad : 1;
 };
 
 struct cipher_test_suite {
@@ -814,27 +827,39 @@ static unsigned int generate_random_length(unsigned int max_len)
 	}
 }
 
-/* Sometimes make some random changes to the given data buffer */
-static void mutate_buffer(u8 *buf, size_t count)
+/* Flip a random bit in the given nonempty data buffer */
+static void flip_random_bit(u8 *buf, size_t size)
+{
+	size_t bitpos;
+
+	bitpos = prandom_u32() % (size * 8);
+	buf[bitpos / 8] ^= 1 << (bitpos % 8);
+}
+
+/* Flip a random byte in the given nonempty data buffer */
+static void flip_random_byte(u8 *buf, size_t size)
+{
+	buf[prandom_u32() % size] ^= 0xff;
+}
+
+/* Sometimes make some random changes to the given nonempty data buffer */
+static void mutate_buffer(u8 *buf, size_t size)
 {
 	size_t num_flips;
 	size_t i;
-	size_t pos;
 
 	/* Sometimes flip some bits */
 	if (prandom_u32() % 4 == 0) {
-		num_flips = min_t(size_t, 1 << (prandom_u32() % 8), count * 8);
-		for (i = 0; i < num_flips; i++) {
-			pos = prandom_u32() % (count * 8);
-			buf[pos / 8] ^= 1 << (pos % 8);
-		}
+		num_flips = min_t(size_t, 1 << (prandom_u32() % 8), size * 8);
+		for (i = 0; i < num_flips; i++)
+			flip_random_bit(buf, size);
 	}
 
 	/* Sometimes flip some bytes */
 	if (prandom_u32() % 4 == 0) {
-		num_flips = min_t(size_t, 1 << (prandom_u32() % 8), count);
+		num_flips = min_t(size_t, 1 << (prandom_u32() % 8), size);
 		for (i = 0; i < num_flips; i++)
-			buf[prandom_u32() % count] ^= 0xff;
+			flip_random_byte(buf, size);
 	}
 }
 
@@ -1915,7 +1940,6 @@ static int test_aead_vec_cfg(const char *driver, int enc,
 		 cfg->iv_offset +
 		 (cfg->iv_offset_relative_to_alignmask ? alignmask : 0);
 	struct kvec input[2];
-	int expected_error;
 	int err;
 
 	/* Set the key */
@@ -2036,20 +2060,31 @@ static int test_aead_vec_cfg(const char *driver, int enc,
 		return -EINVAL;
 	}
 
-	/* Check for success or failure */
-	expected_error = vec->novrfy ? -EBADMSG : vec->crypt_error;
-	if (err) {
-		if (err == expected_error)
-			return 0;
-		pr_err("alg: aead: %s %s failed on test vector %s; expected_error=%d, actual_error=%d, cfg=\"%s\"\n",
-		       driver, op, vec_name, expected_error, err, cfg->name);
-		return err;
-	}
-	if (expected_error) {
-		pr_err("alg: aead: %s %s unexpectedly succeeded on test vector %s; expected_error=%d, cfg=\"%s\"\n",
+	/* Check for unexpected success or failure, or wrong error code */
+	if ((err == 0 && vec->novrfy) ||
+	    (err != vec->crypt_error && !(err == -EBADMSG && vec->novrfy))) {
+		char expected_error[32];
+
+		if (vec->novrfy &&
+		    vec->crypt_error != 0 && vec->crypt_error != -EBADMSG)
+			sprintf(expected_error, "-EBADMSG or %d",
+				vec->crypt_error);
+		else if (vec->novrfy)
+			sprintf(expected_error, "-EBADMSG");
+		else
+			sprintf(expected_error, "%d", vec->crypt_error);
+		if (err) {
+			pr_err("alg: aead: %s %s failed on test vector %s; expected_error=%s, actual_error=%d, cfg=\"%s\"\n",
+			       driver, op, vec_name, expected_error, err,
+			       cfg->name);
+			return err;
+		}
+		pr_err("alg: aead: %s %s unexpectedly succeeded on test vector %s; expected_error=%s, cfg=\"%s\"\n",
 		       driver, op, vec_name, expected_error, cfg->name);
 		return -EINVAL;
 	}
+	if (err) /* Expectedly failed. */
+		return 0;
 
 	/* Check for the correct output (ciphertext or plaintext) */
 	err = verify_correct_output(&tsgls->dst, enc ? vec->ctext : vec->ptext,
@@ -2128,24 +2163,112 @@ struct aead_extra_tests_ctx {
 };
 
 /*
- * Generate an AEAD test vector from the given implementation.
- * Assumes the buffers in 'vec' were already allocated.
+ * Make at least one random change to a (ciphertext, AAD) pair.  "Ciphertext"
+ * here means the full ciphertext including the authentication tag.  The
+ * authentication tag (and hence also the ciphertext) is assumed to be nonempty.
+ */
+static void mutate_aead_message(struct aead_testvec *vec, bool esp_aad)
+{
+	const unsigned int aad_tail_size = esp_aad ? 8 : 0;
+	const unsigned int authsize = vec->clen - vec->plen;
+
+	if (prandom_u32() % 2 == 0 && vec->alen > aad_tail_size) {
+		 /* Mutate the AAD */
+		flip_random_bit((u8 *)vec->assoc, vec->alen - aad_tail_size);
+		if (prandom_u32() % 2 == 0)
+			return;
+	}
+	if (prandom_u32() % 2 == 0) {
+		/* Mutate auth tag (assuming it's at the end of ciphertext) */
+		flip_random_bit((u8 *)vec->ctext + vec->plen, authsize);
+	} else {
+		/* Mutate any part of the ciphertext */
+		flip_random_bit((u8 *)vec->ctext, vec->clen);
+	}
+}
+
+/*
+ * Minimum authentication tag size in bytes at which we assume that we can
+ * reliably generate inauthentic messages, i.e. not generate an authentic
+ * message by chance.
+ */
+#define MIN_COLLISION_FREE_AUTHSIZE 8
+
+static void generate_aead_message(struct aead_request *req,
+				  const struct aead_test_suite *suite,
+				  struct aead_testvec *vec,
+				  bool prefer_inauthentic)
+{
+	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
+	const unsigned int ivsize = crypto_aead_ivsize(tfm);
+	const unsigned int authsize = vec->clen - vec->plen;
+	const bool inauthentic = (authsize >= MIN_COLLISION_FREE_AUTHSIZE) &&
+				 (prefer_inauthentic || prandom_u32() % 4 == 0);
+
+	/* Generate the AAD. */
+	generate_random_bytes((u8 *)vec->assoc, vec->alen);
+
+	if (inauthentic && prandom_u32() % 2 == 0) {
+		/* Generate a random ciphertext. */
+		generate_random_bytes((u8 *)vec->ctext, vec->clen);
+	} else {
+		int i = 0;
+		struct scatterlist src[2], dst;
+		u8 iv[MAX_IVLEN];
+		DECLARE_CRYPTO_WAIT(wait);
+
+		/* Generate a random plaintext and encrypt it. */
+		sg_init_table(src, 2);
+		if (vec->alen)
+			sg_set_buf(&src[i++], vec->assoc, vec->alen);
+		if (vec->plen) {
+			generate_random_bytes((u8 *)vec->ptext, vec->plen);
+			sg_set_buf(&src[i++], vec->ptext, vec->plen);
+		}
+		sg_init_one(&dst, vec->ctext, vec->alen + vec->clen);
+		memcpy(iv, vec->iv, ivsize);
+		aead_request_set_callback(req, 0, crypto_req_done, &wait);
+		aead_request_set_crypt(req, src, &dst, vec->plen, iv);
+		aead_request_set_ad(req, vec->alen);
+		vec->crypt_error = crypto_wait_req(crypto_aead_encrypt(req),
+						   &wait);
+		/* If encryption failed, we're done. */
+		if (vec->crypt_error != 0)
+			return;
+		memmove((u8 *)vec->ctext, vec->ctext + vec->alen, vec->clen);
+		if (!inauthentic)
+			return;
+		/*
+		 * Mutate the authentic (ciphertext, AAD) pair to get an
+		 * inauthentic one.
+		 */
+		mutate_aead_message(vec, suite->esp_aad);
+	}
+	vec->novrfy = 1;
+	if (suite->einval_allowed)
+		vec->crypt_error = -EINVAL;
+}
+
+/*
+ * Generate an AEAD test vector 'vec' using the implementation specified by
+ * 'req'.  The buffers in 'vec' must already be allocated.
+ *
+ * If 'prefer_inauthentic' is true, then this function will generate inauthentic
+ * test vectors (i.e. vectors with 'vec->novrfy=1') more often.
  */
 static void generate_random_aead_testvec(struct aead_request *req,
 					 struct aead_testvec *vec,
+					 const struct aead_test_suite *suite,
 					 unsigned int maxkeysize,
 					 unsigned int maxdatasize,
-					 char *name, size_t max_namelen)
+					 char *name, size_t max_namelen,
+					 bool prefer_inauthentic)
 {
 	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 	const unsigned int ivsize = crypto_aead_ivsize(tfm);
 	const unsigned int maxauthsize = crypto_aead_maxauthsize(tfm);
 	unsigned int authsize;
 	unsigned int total_len;
-	int i;
-	struct scatterlist src[2], dst;
-	u8 iv[MAX_IVLEN];
-	DECLARE_CRYPTO_WAIT(wait);
 
 	/* Key: length in [0, maxkeysize], but usually choose maxkeysize */
 	vec->klen = maxkeysize;
@@ -2161,50 +2284,83 @@ static void generate_random_aead_testvec(struct aead_request *req,
 	authsize = maxauthsize;
 	if (prandom_u32() % 4 == 0)
 		authsize = prandom_u32() % (maxauthsize + 1);
+	if (prefer_inauthentic && authsize < MIN_COLLISION_FREE_AUTHSIZE)
+		authsize = MIN_COLLISION_FREE_AUTHSIZE;
 	if (WARN_ON(authsize > maxdatasize))
 		authsize = maxdatasize;
 	maxdatasize -= authsize;
 	vec->setauthsize_error = crypto_aead_setauthsize(tfm, authsize);
 
-	/* Plaintext and associated data */
+	/* AAD, plaintext, and ciphertext lengths */
 	total_len = generate_random_length(maxdatasize);
 	if (prandom_u32() % 4 == 0)
 		vec->alen = 0;
 	else
 		vec->alen = generate_random_length(total_len);
 	vec->plen = total_len - vec->alen;
-	generate_random_bytes((u8 *)vec->assoc, vec->alen);
-	generate_random_bytes((u8 *)vec->ptext, vec->plen);
-
 	vec->clen = vec->plen + authsize;
 
 	/*
-	 * If the key or authentication tag size couldn't be set, no need to
-	 * continue to encrypt.
+	 * Generate the AAD, plaintext, and ciphertext.  Not applicable if the
+	 * key or the authentication tag size couldn't be set.
 	 */
+	vec->novrfy = 0;
 	vec->crypt_error = 0;
-	if (vec->setkey_error || vec->setauthsize_error)
-		goto done;
-
-	/* Ciphertext */
-	sg_init_table(src, 2);
-	i = 0;
-	if (vec->alen)
-		sg_set_buf(&src[i++], vec->assoc, vec->alen);
-	if (vec->plen)
-		sg_set_buf(&src[i++], vec->ptext, vec->plen);
-	sg_init_one(&dst, vec->ctext, vec->alen + vec->clen);
-	memcpy(iv, vec->iv, ivsize);
-	aead_request_set_callback(req, 0, crypto_req_done, &wait);
-	aead_request_set_crypt(req, src, &dst, vec->plen, iv);
-	aead_request_set_ad(req, vec->alen);
-	vec->crypt_error = crypto_wait_req(crypto_aead_encrypt(req), &wait);
-	if (vec->crypt_error == 0)
-		memmove((u8 *)vec->ctext, vec->ctext + vec->alen, vec->clen);
-done:
+	if (vec->setkey_error == 0 && vec->setauthsize_error == 0)
+		generate_aead_message(req, suite, vec, prefer_inauthentic);
 	snprintf(name, max_namelen,
-		 "\"random: alen=%u plen=%u authsize=%u klen=%u\"",
-		 vec->alen, vec->plen, authsize, vec->klen);
+		 "\"random: alen=%u plen=%u authsize=%u klen=%u novrfy=%d\"",
+		 vec->alen, vec->plen, authsize, vec->klen, vec->novrfy);
+}
+
+static void try_to_generate_inauthentic_testvec(
+					struct aead_extra_tests_ctx *ctx)
+{
+	int i;
+
+	for (i = 0; i < 10; i++) {
+		generate_random_aead_testvec(ctx->req, &ctx->vec,
+					     &ctx->test_desc->suite.aead,
+					     ctx->maxkeysize, ctx->maxdatasize,
+					     ctx->vec_name,
+					     sizeof(ctx->vec_name), true);
+		if (ctx->vec.novrfy)
+			return;
+	}
+}
+
+/*
+ * Generate inauthentic test vectors (i.e. ciphertext, AAD pairs that aren't the
+ * result of an encryption with the key) and verify that decryption fails.
+ */
+static int test_aead_inauthentic_inputs(struct aead_extra_tests_ctx *ctx)
+{
+	unsigned int i;
+	int err;
+
+	for (i = 0; i < fuzz_iterations * 8; i++) {
+		/*
+		 * Since this part of the tests isn't comparing the
+		 * implementation to another, there's no point in testing any
+		 * test vectors other than inauthentic ones (vec.novrfy=1) here.
+		 *
+		 * If we're having trouble generating such a test vector, e.g.
+		 * if the algorithm keeps rejecting the generated keys, don't
+		 * retry forever; just continue on.
+		 */
+		try_to_generate_inauthentic_testvec(ctx);
+		if (ctx->vec.novrfy) {
+			generate_random_testvec_config(&ctx->cfg, ctx->cfgname,
+						       sizeof(ctx->cfgname));
+			err = test_aead_vec_cfg(ctx->driver, DECRYPT, &ctx->vec,
+						ctx->vec_name, &ctx->cfg,
+						ctx->req, ctx->tsgls);
+			if (err)
+				return err;
+		}
+		cond_resched();
+	}
+	return 0;
 }
 
 /*
@@ -2285,17 +2441,20 @@ static int test_aead_vs_generic_impl(struct aead_extra_tests_ctx *ctx)
 	 */
 	for (i = 0; i < fuzz_iterations * 8; i++) {
 		generate_random_aead_testvec(generic_req, &ctx->vec,
+					     &ctx->test_desc->suite.aead,
 					     ctx->maxkeysize, ctx->maxdatasize,
 					     ctx->vec_name,
-					     sizeof(ctx->vec_name));
+					     sizeof(ctx->vec_name), false);
 		generate_random_testvec_config(&ctx->cfg, ctx->cfgname,
 					       sizeof(ctx->cfgname));
-		err = test_aead_vec_cfg(driver, ENCRYPT, &ctx->vec,
-					ctx->vec_name, &ctx->cfg,
-					ctx->req, ctx->tsgls);
-		if (err)
-			goto out;
-		if (ctx->vec.crypt_error == 0) {
+		if (!ctx->vec.novrfy) {
+			err = test_aead_vec_cfg(driver, ENCRYPT, &ctx->vec,
+						ctx->vec_name, &ctx->cfg,
+						ctx->req, ctx->tsgls);
+			if (err)
+				goto out;
+		}
+		if (ctx->vec.crypt_error == 0 || ctx->vec.novrfy) {
 			err = test_aead_vec_cfg(driver, DECRYPT, &ctx->vec,
 						ctx->vec_name, &ctx->cfg,
 						ctx->req, ctx->tsgls);
@@ -2348,6 +2507,10 @@ static int test_aead_extra(const char *driver,
 		goto out;
 	}
 
+	err = test_aead_inauthentic_inputs(ctx);
+	if (err)
+		goto out;
+
 	err = test_aead_vs_generic_impl(ctx);
 out:
 	kfree(ctx->vec.key);
@@ -3978,7 +4141,8 @@ static int alg_test_null(const struct alg_test_desc *desc,
 	return 0;
 }
 
-#define __VECS(tv)	{ .vecs = tv, .count = ARRAY_SIZE(tv) }
+#define ____VECS(tv)	.vecs = tv, .count = ARRAY_SIZE(tv)
+#define __VECS(tv)	{ ____VECS(tv) }
 
 /* Please keep this list sorted by algorithm name. */
 static const struct alg_test_desc alg_test_descs[] = {
@@ -4284,7 +4448,10 @@ static const struct alg_test_desc alg_test_descs[] = {
 		.test = alg_test_aead,
 		.fips_allowed = 1,
 		.suite = {
-			.aead = __VECS(aes_ccm_tv_template)
+			.aead = {
+				____VECS(aes_ccm_tv_template),
+				.einval_allowed = 1,
+			}
 		}
 	}, {
 		.alg = "cfb(aes)",
@@ -5032,7 +5199,11 @@ static const struct alg_test_desc alg_test_descs[] = {
 		.test = alg_test_aead,
 		.fips_allowed = 1,
 		.suite = {
-			.aead = __VECS(aes_gcm_rfc4106_tv_template)
+			.aead = {
+				____VECS(aes_gcm_rfc4106_tv_template),
+				.einval_allowed = 1,
+				.esp_aad = 1,
+			}
 		}
 	}, {
 		.alg = "rfc4309(ccm(aes))",
@@ -5040,14 +5211,21 @@ static const struct alg_test_desc alg_test_descs[] = {
 		.test = alg_test_aead,
 		.fips_allowed = 1,
 		.suite = {
-			.aead = __VECS(aes_ccm_rfc4309_tv_template)
+			.aead = {
+				____VECS(aes_ccm_rfc4309_tv_template),
+				.einval_allowed = 1,
+				.esp_aad = 1,
+			}
 		}
 	}, {
 		.alg = "rfc4543(gcm(aes))",
 		.generic_driver = "rfc4543(gcm_base(ctr(aes-generic),ghash-generic))",
 		.test = alg_test_aead,
 		.suite = {
-			.aead = __VECS(aes_gcm_rfc4543_tv_template)
+			.aead = {
+				____VECS(aes_gcm_rfc4543_tv_template),
+				.einval_allowed = 1,
+			}
 		}
 	}, {
 		.alg = "rfc7539(chacha20,poly1305)",
@@ -5059,7 +5237,11 @@ static const struct alg_test_desc alg_test_descs[] = {
 		.alg = "rfc7539esp(chacha20,poly1305)",
 		.test = alg_test_aead,
 		.suite = {
-			.aead = __VECS(rfc7539esp_tv_template)
+			.aead = {
+				____VECS(rfc7539esp_tv_template),
+				.einval_allowed = 1,
+				.esp_aad = 1,
+			}
 		}
 	}, {
 		.alg = "rmd128",
diff --git a/crypto/testmgr.h b/crypto/testmgr.h
index 48da646651cb..d29983908c38 100644
--- a/crypto/testmgr.h
+++ b/crypto/testmgr.h
@@ -85,16 +85,22 @@ struct cipher_testvec {
  * @ctext:	Pointer to the full authenticated ciphertext.  For AEADs that
  *		produce a separate "ciphertext" and "authentication tag", these
  *		two parts are concatenated: ciphertext || tag.
- * @novrfy:	Decryption verification failure expected?
+ * @novrfy:	If set, this is an inauthentic input test: only decryption is
+ *		tested, and it is expected to fail with either -EBADMSG or
+ *		@crypt_error if it is nonzero.
  * @wk:		Does the test need CRYPTO_TFM_REQ_FORBID_WEAK_KEYS?
  *		(e.g. setkey() needs to fail due to a weak key)
  * @klen:	Length of @key in bytes
  * @plen:	Length of @ptext in bytes
  * @alen:	Length of @assoc in bytes
  * @clen:	Length of @ctext in bytes
- * @setkey_error: Expected error from setkey()
- * @setauthsize_error: Expected error from setauthsize()
- * @crypt_error: Expected error from encrypt() and decrypt()
+ * @setkey_error: Expected error from setkey().  If set, neither encryption nor
+ *		  decryption is tested.
+ * @setauthsize_error: Expected error from setauthsize().  If set, neither
+ *		       encryption nor decryption is tested.
+ * @crypt_error: When @novrfy=0, the expected error from encrypt().  When
+ *		 @novrfy=1, an optional alternate error code that is acceptable
+ *		 for decrypt() to return besides -EBADMSG.
  */
 struct aead_testvec {
 	const char *key;