crypto: authenc - Move saved IV in front of the ablkcipher request
In crypto_authenc_encrypt() we save the IV behind the ablkcipher
request. To save space on the request, we overwrite the ablkcipher
request with a ahash request after encryption. So the IV may be
overwritten by the ahash request. This patch fixes this by placing
the IV in front of the ablkcipher/ahash request.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/crypto/authenc.c b/crypto/authenc.c
index 6287cfd..2bb7348 100644
--- a/crypto/authenc.c
+++ b/crypto/authenc.c
@@ -386,11 +386,13 @@
{
struct crypto_aead *authenc = crypto_aead_reqtfm(req);
struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
- struct ablkcipher_request *abreq = aead_request_ctx(req);
+ struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
struct crypto_ablkcipher *enc = ctx->enc;
struct scatterlist *dst = req->dst;
unsigned int cryptlen = req->cryptlen;
- u8 *iv = (u8 *)(abreq + 1) + crypto_ablkcipher_reqsize(enc);
+ struct ablkcipher_request *abreq = (void *)(areq_ctx->tail
+ + ctx->reqoff);
+ u8 *iv = (u8 *)abreq - crypto_ablkcipher_ivsize(enc);
int err;
ablkcipher_request_set_tfm(abreq, enc);
@@ -546,10 +548,6 @@
if (IS_ERR(auth))
return PTR_ERR(auth);
- ctx->reqoff = ALIGN(2 * crypto_ahash_digestsize(auth) +
- crypto_ahash_alignmask(auth),
- crypto_ahash_alignmask(auth) + 1);
-
enc = crypto_spawn_skcipher(&ictx->enc);
err = PTR_ERR(enc);
if (IS_ERR(enc))
@@ -558,13 +556,18 @@
ctx->auth = auth;
ctx->enc = enc;
- tfm->crt_aead.reqsize = max_t(unsigned int,
- crypto_ahash_reqsize(auth) + ctx->reqoff +
- sizeof(struct authenc_request_ctx) +
+ ctx->reqoff = ALIGN(2 * crypto_ahash_digestsize(auth) +
+ crypto_ahash_alignmask(auth),
+ crypto_ahash_alignmask(auth) + 1) +
+ crypto_ablkcipher_ivsize(enc);
+
+ tfm->crt_aead.reqsize = sizeof(struct authenc_request_ctx) +
+ ctx->reqoff +
+ max_t(unsigned int,
+ crypto_ahash_reqsize(auth) +
sizeof(struct ahash_request),
sizeof(struct skcipher_givcrypt_request) +
- crypto_ablkcipher_reqsize(enc) +
- crypto_ablkcipher_ivsize(enc));
+ crypto_ablkcipher_reqsize(enc));
return 0;