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 <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Eric Biggers 2018-01-03 11:16:26 -08:00 committed by Herbert Xu
parent a16e772e66
commit a208fa8f33
15 changed files with 30 additions and 9 deletions

View File

@ -188,6 +188,7 @@ static struct shash_alg crc32_pmull_algs[] = { {
.base.cra_name = "crc32",
.base.cra_driver_name = "crc32-arm-ce",
.base.cra_priority = 200,
.base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
.base.cra_blocksize = 1,
.base.cra_module = THIS_MODULE,
}, {
@ -203,6 +204,7 @@ static struct shash_alg crc32_pmull_algs[] = { {
.base.cra_name = "crc32c",
.base.cra_driver_name = "crc32c-arm-ce",
.base.cra_priority = 200,
.base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
.base.cra_blocksize = 1,
.base.cra_module = THIS_MODULE,
} };

View File

@ -185,6 +185,7 @@ static struct shash_alg crc32_pmull_algs[] = { {
.base.cra_name = "crc32",
.base.cra_driver_name = "crc32-arm64-ce",
.base.cra_priority = 200,
.base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
.base.cra_blocksize = 1,
.base.cra_module = THIS_MODULE,
}, {
@ -200,6 +201,7 @@ static struct shash_alg crc32_pmull_algs[] = { {
.base.cra_name = "crc32c",
.base.cra_driver_name = "crc32c-arm64-ce",
.base.cra_priority = 200,
.base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
.base.cra_blocksize = 1,
.base.cra_module = THIS_MODULE,
} };

View File

@ -141,6 +141,7 @@ static struct shash_alg alg = {
.cra_name = "crc32c",
.cra_driver_name = "crc32c-vpmsum",
.cra_priority = 200,
.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
.cra_blocksize = CHKSUM_BLOCK_SIZE,
.cra_ctxsize = sizeof(u32),
.cra_module = THIS_MODULE,

View File

@ -239,6 +239,7 @@ static struct shash_alg crc32_vx_algs[] = {
.cra_name = "crc32",
.cra_driver_name = "crc32-vx",
.cra_priority = 200,
.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
.cra_blocksize = CRC32_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct crc_ctx),
.cra_module = THIS_MODULE,
@ -259,6 +260,7 @@ static struct shash_alg crc32_vx_algs[] = {
.cra_name = "crc32be",
.cra_driver_name = "crc32be-vx",
.cra_priority = 200,
.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
.cra_blocksize = CRC32_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct crc_ctx),
.cra_module = THIS_MODULE,
@ -279,6 +281,7 @@ static struct shash_alg crc32_vx_algs[] = {
.cra_name = "crc32c",
.cra_driver_name = "crc32c-vx",
.cra_priority = 200,
.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
.cra_blocksize = CRC32_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct crc_ctx),
.cra_module = THIS_MODULE,

View File

@ -133,6 +133,7 @@ static struct shash_alg alg = {
.cra_name = "crc32c",
.cra_driver_name = "crc32c-sparc64",
.cra_priority = SPARC_CR_OPCODE_PRIORITY,
.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
.cra_blocksize = CHKSUM_BLOCK_SIZE,
.cra_ctxsize = sizeof(u32),
.cra_alignmask = 7,

View File

@ -162,6 +162,7 @@ static struct shash_alg alg = {
.cra_name = "crc32",
.cra_driver_name = "crc32-pclmul",
.cra_priority = 200,
.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
.cra_blocksize = CHKSUM_BLOCK_SIZE,
.cra_ctxsize = sizeof(u32),
.cra_module = THIS_MODULE,

View File

@ -226,6 +226,7 @@ static struct shash_alg alg = {
.cra_name = "crc32c",
.cra_driver_name = "crc32c-intel",
.cra_priority = 200,
.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
.cra_blocksize = CHKSUM_BLOCK_SIZE,
.cra_ctxsize = sizeof(u32),
.cra_module = THIS_MODULE,

View File

@ -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,

View File

@ -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),

View File

@ -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;

View File

@ -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;

View File

@ -494,7 +494,8 @@ static struct ahash_alg algs = {
.cra_driver_name = DRIVER_NAME,
.cra_priority = 100,
.cra_flags = CRYPTO_ALG_TYPE_AHASH |
CRYPTO_ALG_ASYNC,
CRYPTO_ALG_ASYNC |
CRYPTO_ALG_OPTIONAL_KEY,
.cra_blocksize = CHKSUM_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct bfin_crypto_crc_ctx),
.cra_alignmask = 3,

View File

@ -208,6 +208,7 @@ static struct shash_alg algs[] = {
.cra_name = "crc32",
.cra_driver_name = DRIVER_NAME,
.cra_priority = 200,
.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
.cra_blocksize = CHKSUM_BLOCK_SIZE,
.cra_alignmask = 3,
.cra_ctxsize = sizeof(struct stm32_crc_ctx),
@ -229,6 +230,7 @@ static struct shash_alg algs[] = {
.cra_name = "crc32c",
.cra_driver_name = DRIVER_NAME,
.cra_priority = 200,
.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
.cra_blocksize = CHKSUM_BLOCK_SIZE,
.cra_alignmask = 3,
.cra_ctxsize = sizeof(struct stm32_crc_ctx),

View File

@ -120,6 +120,7 @@ static struct shash_alg alg = {
.cra_name = "adler32",
.cra_driver_name = "adler32-zlib",
.cra_priority = 100,
.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
.cra_blocksize = CHKSUM_BLOCK_SIZE,
.cra_ctxsize = sizeof(u32),
.cra_module = THIS_MODULE,

View File

@ -106,6 +106,12 @@
*/
#define CRYPTO_ALG_INTERNAL 0x00002000
/*
* Set if the algorithm has a ->setkey() method but can be used without
* calling it first, i.e. there is a default key.
*/
#define CRYPTO_ALG_OPTIONAL_KEY 0x00004000
/*
* Transform masks and values (for crt_flags).
*/