From a208fa8f33031b9e0aba44c7d1b7e68eb0cbd29e Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Wed, 3 Jan 2018 11:16:26 -0800 Subject: crypto: hash - annotate algorithms taking optional key We need to consistently enforce that keyed hashes cannot be used without setting the key. To do this we need a reliable way to determine whether a given hash algorithm is keyed or not. AF_ALG currently does this by checking for the presence of a ->setkey() method. However, this is actually slightly broken because the CRC-32 algorithms implement ->setkey() but can also be used without a key. (The CRC-32 "key" is not actually a cryptographic key but rather represents the initial state. If not overridden, then a default initial state is used.) Prepare to fix this by introducing a flag CRYPTO_ALG_OPTIONAL_KEY which indicates that the algorithm has a ->setkey() method, but it is not required to be called. Then set it on all the CRC-32 algorithms. The same also applies to the Adler-32 implementation in Lustre. Also, the cryptd and mcryptd templates have to pass through the flag from their underlying algorithm. Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu --- crypto/crc32_generic.c | 1 + crypto/crc32c_generic.c | 1 + crypto/cryptd.c | 7 +++---- crypto/mcryptd.c | 7 +++---- 4 files changed, 8 insertions(+), 8 deletions(-) (limited to 'crypto') diff --git a/crypto/crc32_generic.c b/crypto/crc32_generic.c index aa2a25fc7482..718cbce8d169 100644 --- a/crypto/crc32_generic.c +++ b/crypto/crc32_generic.c @@ -133,6 +133,7 @@ static struct shash_alg alg = { .cra_name = "crc32", .cra_driver_name = "crc32-generic", .cra_priority = 100, + .cra_flags = CRYPTO_ALG_OPTIONAL_KEY, .cra_blocksize = CHKSUM_BLOCK_SIZE, .cra_ctxsize = sizeof(u32), .cra_module = THIS_MODULE, diff --git a/crypto/crc32c_generic.c b/crypto/crc32c_generic.c index 4c0a0e271876..372320399622 100644 --- a/crypto/crc32c_generic.c +++ b/crypto/crc32c_generic.c @@ -146,6 +146,7 @@ static struct shash_alg alg = { .cra_name = "crc32c", .cra_driver_name = "crc32c-generic", .cra_priority = 100, + .cra_flags = CRYPTO_ALG_OPTIONAL_KEY, .cra_blocksize = CHKSUM_BLOCK_SIZE, .cra_alignmask = 3, .cra_ctxsize = sizeof(struct chksum_ctx), diff --git a/crypto/cryptd.c b/crypto/cryptd.c index 457ae3e66a41..addca7bae33f 100644 --- a/crypto/cryptd.c +++ b/crypto/cryptd.c @@ -896,10 +896,9 @@ static int cryptd_create_hash(struct crypto_template *tmpl, struct rtattr **tb, if (err) goto out_free_inst; - type = CRYPTO_ALG_ASYNC; - if (alg->cra_flags & CRYPTO_ALG_INTERNAL) - type |= CRYPTO_ALG_INTERNAL; - inst->alg.halg.base.cra_flags = type; + inst->alg.halg.base.cra_flags = CRYPTO_ALG_ASYNC | + (alg->cra_flags & (CRYPTO_ALG_INTERNAL | + CRYPTO_ALG_OPTIONAL_KEY)); inst->alg.halg.digestsize = salg->digestsize; inst->alg.halg.statesize = salg->statesize; diff --git a/crypto/mcryptd.c b/crypto/mcryptd.c index ace346b976b3..fe5129d6ff4e 100644 --- a/crypto/mcryptd.c +++ b/crypto/mcryptd.c @@ -516,10 +516,9 @@ static int mcryptd_create_hash(struct crypto_template *tmpl, struct rtattr **tb, if (err) goto out_free_inst; - type = CRYPTO_ALG_ASYNC; - if (alg->cra_flags & CRYPTO_ALG_INTERNAL) - type |= CRYPTO_ALG_INTERNAL; - inst->alg.halg.base.cra_flags = type; + inst->alg.halg.base.cra_flags = CRYPTO_ALG_ASYNC | + (alg->cra_flags & (CRYPTO_ALG_INTERNAL | + CRYPTO_ALG_OPTIONAL_KEY)); inst->alg.halg.digestsize = halg->digestsize; inst->alg.halg.statesize = halg->statesize; -- cgit