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;