Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

crypto: aead - prevent using AEADs without setting key

Browse source 
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
Show stats Download patch file Download diff file Expand all files Collapse all files

13
crypto/aead.c
View file

@ -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)

11
crypto/algif_aead.c
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);

10
include/crypto/aead.h
View file

@ -327,7 +327,12 @@ static inline struct crypto_aead *crypto_aead_reqtfm(struct aead_request *req)
*/
static inline int crypto_aead_encrypt(struct aead_request *req)
{
return crypto_aead_alg(crypto_aead_reqtfm(req))->encrypt(req);
struct crypto_aead *aead = crypto_aead_reqtfm(req);
if (crypto_aead_get_flags(aead) & CRYPTO_TFM_NEED_KEY)
return -ENOKEY;
return crypto_aead_alg(aead)->encrypt(req);
}
/**
@ -356,6 +361,9 @@ static inline int crypto_aead_decrypt(struct aead_request *req)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
if (crypto_aead_get_flags(aead) & CRYPTO_TFM_NEED_KEY)
return -ENOKEY;
if (req->cryptlen < crypto_aead_authsize(aead))
return -EINVAL;