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>
diff --git a/crypto/authenc.c b/crypto/authenc.c
index 2b3f4ab..1875e70 100644
--- a/crypto/authenc.c
+++ b/crypto/authenc.c
@@ -52,40 +52,52 @@
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 @@
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);