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>
diff --git a/crypto/aead.c b/crypto/aead.c
index fe00cbd..60b3bbe 100644
--- a/crypto/aead.c
+++ b/crypto/aead.c
@@ -54,11 +54,18 @@ int crypto_aead_setkey(struct crypto_aead *tfm,
const u8 *key, unsigned int keylen)
{
unsigned long alignmask = crypto_aead_alignmask(tfm);
+ int err;
if ((unsigned long)key & alignmask)
- return setkey_unaligned(tfm, key, keylen);
+ err = setkey_unaligned(tfm, key, keylen);
+ else
+ err = crypto_aead_alg(tfm)->setkey(tfm, key, keylen);
- return crypto_aead_alg(tfm)->setkey(tfm, key, keylen);
+ if (err)
+ return err;
+
+ crypto_aead_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
+ return 0;
}
EXPORT_SYMBOL_GPL(crypto_aead_setkey);
@@ -93,6 +100,8 @@ static int crypto_aead_init_tfm(struct crypto_tfm *tfm)
struct crypto_aead *aead = __crypto_aead_cast(tfm);
struct aead_alg *alg = crypto_aead_alg(aead);
+ crypto_aead_set_flags(aead, CRYPTO_TFM_NEED_KEY);
+
aead->authsize = alg->maxauthsize;
if (alg->exit)
diff --git a/crypto/algif_aead.c b/crypto/algif_aead.c
index d963c8c..4b07edd 100644
--- a/crypto/algif_aead.c
+++ b/crypto/algif_aead.c
@@ -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);
