crypto: authenc - Export key parsing helper function

AEAD key parsing is duplicated to multiple places in the kernel. Add a
common helper function to consolidate that functionality.

Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Mathias Krause <mathias.krause@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Mathias Krause 2013-10-15 13:49:30 +02:00 committed by syphyr
parent 742fa3f72b
commit 6ee3956afc
2 changed files with 41 additions and 19 deletions

View File

@ -52,40 +52,52 @@ static void authenc_request_complete(struct aead_request *req, int err)
aead_request_complete(req, err);
}
static int crypto_authenc_setkey(struct crypto_aead *authenc, const u8 *key,
unsigned int keylen)
int crypto_authenc_extractkeys(struct crypto_authenc_keys *keys, const u8 *key,
unsigned int keylen)
{
unsigned int authkeylen;
unsigned int enckeylen;
struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
struct crypto_ahash *auth = ctx->auth;
struct crypto_ablkcipher *enc = ctx->enc;
struct rtattr *rta = (void *)key;
struct rtattr *rta = (struct rtattr *)key;
struct crypto_authenc_key_param *param;
int err = -EINVAL;
if (!RTA_OK(rta, keylen))
goto badkey;
return -EINVAL;
if (rta->rta_type != CRYPTO_AUTHENC_KEYA_PARAM)
goto badkey;
return -EINVAL;
if (RTA_PAYLOAD(rta) < sizeof(*param))
goto badkey;
return -EINVAL;
param = RTA_DATA(rta);
enckeylen = be32_to_cpu(param->enckeylen);
keys->enckeylen = be32_to_cpu(param->enckeylen);
key += RTA_ALIGN(rta->rta_len);
keylen -= RTA_ALIGN(rta->rta_len);
if (keylen < enckeylen)
goto badkey;
if (keylen < keys->enckeylen)
return -EINVAL;
authkeylen = keylen - enckeylen;
keys->authkeylen = keylen - keys->enckeylen;
keys->authkey = key;
keys->enckey = key + keys->authkeylen;
return 0;
}
EXPORT_SYMBOL_GPL(crypto_authenc_extractkeys);
static int crypto_authenc_setkey(struct crypto_aead *authenc, const u8 *key,
unsigned int keylen)
{
struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
struct crypto_ahash *auth = ctx->auth;
struct crypto_ablkcipher *enc = ctx->enc;
struct crypto_authenc_keys keys;
int err = -EINVAL;
if (crypto_authenc_extractkeys(&keys, key, keylen) != 0)
goto badkey;
crypto_ahash_clear_flags(auth, CRYPTO_TFM_REQ_MASK);
crypto_ahash_set_flags(auth, crypto_aead_get_flags(authenc) &
CRYPTO_TFM_REQ_MASK);
err = crypto_ahash_setkey(auth, key, authkeylen);
err = crypto_ahash_setkey(auth, keys.authkey, keys.authkeylen);
crypto_aead_set_flags(authenc, crypto_ahash_get_flags(auth) &
CRYPTO_TFM_RES_MASK);
@ -95,7 +107,7 @@ static int crypto_authenc_setkey(struct crypto_aead *authenc, const u8 *key,
crypto_ablkcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK);
crypto_ablkcipher_set_flags(enc, crypto_aead_get_flags(authenc) &
CRYPTO_TFM_REQ_MASK);
err = crypto_ablkcipher_setkey(enc, key + authkeylen, enckeylen);
err = crypto_ablkcipher_setkey(enc, keys.enckey, keys.enckeylen);
crypto_aead_set_flags(authenc, crypto_ablkcipher_get_flags(enc) &
CRYPTO_TFM_RES_MASK);

View File

@ -23,5 +23,15 @@ struct crypto_authenc_key_param {
__be32 enckeylen;
};
#endif /* _CRYPTO_AUTHENC_H */
struct crypto_authenc_keys {
const u8 *authkey;
const u8 *enckey;
unsigned int authkeylen;
unsigned int enckeylen;
};
int crypto_authenc_extractkeys(struct crypto_authenc_keys *keys, const u8 *key,
unsigned int keylen);
#endif /* _CRYPTO_AUTHENC_H */