[04/12] crypto: axis - fix in-place CBC output IV
Commit Message
When CBC is done in-place, the ->src is overwritten by the time the
operation is done, so the output IV must be based on a backup of the
ciphertext.
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
---
drivers/crypto/axis/artpec6_crypto.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
@@ -321,6 +321,7 @@ struct artpec6_crypto_request_context {
u32 cipher_md;
bool decrypt;
struct artpec6_crypto_req_common common;
+ unsigned char last_ciphertext[AES_BLOCK_SIZE];
unsigned char iv_bounce[AES_BLOCK_SIZE] CRYPTO_MINALIGN_ATTR;
};
@@ -1158,6 +1159,10 @@ static int artpec6_crypto_decrypt(struct skcipher_request *req)
switch (ctx->crypto_type) {
case ARTPEC6_CRYPTO_CIPHER_AES_CBC:
+ scatterwalk_map_and_copy(req_ctx->last_ciphertext, req->src,
+ req->cryptlen - sizeof(req_ctx->last_ciphertext),
+ sizeof(req_ctx->last_ciphertext), 0);
+
complete = artpec6_crypto_complete_cbc_decrypt;
break;
case ARTPEC6_CRYPTO_CIPHER_AES_CTR:
@@ -2185,10 +2190,10 @@ artpec6_crypto_complete_cbc_decrypt(struct crypto_async_request *req)
{
struct skcipher_request *cipher_req = container_of(req,
struct skcipher_request, base);
+ struct artpec6_crypto_request_context *req_ctx = skcipher_request_ctx(cipher_req);
+
+ memcpy(cipher_req->iv, req_ctx->last_ciphertext, sizeof(req_ctx->last_ciphertext));
- scatterwalk_map_and_copy(cipher_req->iv, cipher_req->src,
- cipher_req->cryptlen - AES_BLOCK_SIZE,
- AES_BLOCK_SIZE, 0);
req->complete(req, 0);
}