crypto: aead - prevent using AEADs without setting key

Similar to what was done for the hash API, update the AEAD API to track
whether each transform has been keyed, and reject encryption/decryption
if a key is needed but one hasn't been set.

This isn't quite as important as the equivalent fix for the hash API
because AEADs always require a key, so are unlikely to be used without
one.  Still, tracking the key will prevent accidental unkeyed use.
algif_aead also had to track the key anyway, so the new flag replaces
that and slightly simplifies the algif_aead implementation.

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 11:16:30 -08:00
committed by Herbert Xu
parent f8d33fac84
commit dc26c17f74
3 changed files with 23 additions and 11 deletions

View File

@@ -42,7 +42,6 @@
struct aead_tfm {
struct crypto_aead *aead;
bool has_key;
struct crypto_skcipher *null_tfm;
};
@@ -398,7 +397,7 @@ static int aead_check_key(struct socket *sock)
err = -ENOKEY;
lock_sock_nested(psk, SINGLE_DEPTH_NESTING);
if (!tfm->has_key)
if (crypto_aead_get_flags(tfm->aead) & CRYPTO_TFM_NEED_KEY)
goto unlock;
if (!pask->refcnt++)
@@ -523,12 +522,8 @@ static int aead_setauthsize(void *private, unsigned int authsize)
static int aead_setkey(void *private, const u8 *key, unsigned int keylen)
{
struct aead_tfm *tfm = private;
int err;
err = crypto_aead_setkey(tfm->aead, key, keylen);
tfm->has_key = !err;
return err;
return crypto_aead_setkey(tfm->aead, key, keylen);
}
static void aead_sock_destruct(struct sock *sk)
@@ -589,7 +584,7 @@ static int aead_accept_parent(void *private, struct sock *sk)
{
struct aead_tfm *tfm = private;
if (!tfm->has_key)
if (crypto_aead_get_flags(tfm->aead) & CRYPTO_TFM_NEED_KEY)
return -ENOKEY;
return aead_accept_parent_nokey(private, sk);