@@ -1907,7 +1907,7 @@ static int artpec6_crypto_prepare_aead(struct aead_request *areq)
/* For the decryption, cryptlen includes the tag. */
input_length = areq->cryptlen;
if (req_ctx->decrypt)
- input_length -= AES_BLOCK_SIZE;
+ input_length -= crypto_aead_authsize(cipher);
/* Prepare the context buffer */
req_ctx->hw_ctx.aad_length_bits =
@@ -1972,7 +1972,7 @@ static int artpec6_crypto_prepare_aead(struct aead_request *areq)
size_t output_len = areq->cryptlen;
if (req_ctx->decrypt)
- output_len -= AES_BLOCK_SIZE;
+ output_len -= crypto_aead_authsize(cipher);
artpec6_crypto_walk_init(&walk, areq->dst);
@@ -2001,19 +2001,32 @@ static int artpec6_crypto_prepare_aead(struct aead_request *areq)
* the output ciphertext. For decryption it is put in a context
* buffer for later compare against the input tag.
*/
- count = AES_BLOCK_SIZE;
if (req_ctx->decrypt) {
ret = artpec6_crypto_setup_in_descr(common,
- req_ctx->decryption_tag, count, false);
+ req_ctx->decryption_tag, AES_BLOCK_SIZE, false);
if (ret)
return ret;
} else {
+ /* For encryption the requested tag size may be smaller
+ * than the hardware's generated tag.
+ */
+ size_t authsize = crypto_aead_authsize(cipher);
+
ret = artpec6_crypto_setup_sg_descrs_in(common, &walk,
- count);
+ authsize);
if (ret)
return ret;
+
+ if (authsize < AES_BLOCK_SIZE) {
+ count = AES_BLOCK_SIZE - authsize;
+ ret = artpec6_crypto_setup_in_descr(common,
+ ac->pad_buffer,
+ count, false);
+ if (ret)
+ return ret;
+ }
}
}
@@ -2174,27 +2187,29 @@ static void artpec6_crypto_complete_aead(struct crypto_async_request *req)
/* Verify GCM hashtag. */
struct aead_request *areq = container_of(req,
struct aead_request, base);
+ struct crypto_aead *aead = crypto_aead_reqtfm(areq);
struct artpec6_crypto_aead_req_ctx *req_ctx = aead_request_ctx(areq);
if (req_ctx->decrypt) {
u8 input_tag[AES_BLOCK_SIZE];
+ unsigned int authsize = crypto_aead_authsize(aead);
sg_pcopy_to_buffer(areq->src,
sg_nents(areq->src),
input_tag,
- AES_BLOCK_SIZE,
+ authsize,
areq->assoclen + areq->cryptlen -
- AES_BLOCK_SIZE);
+ authsize);
if (memcmp(req_ctx->decryption_tag,
input_tag,
- AES_BLOCK_SIZE)) {
+ authsize)) {
pr_debug("***EBADMSG:\n");
print_hex_dump_debug("ref:", DUMP_PREFIX_ADDRESS, 32, 1,
- input_tag, AES_BLOCK_SIZE, true);
+ input_tag, authsize, true);
print_hex_dump_debug("out:", DUMP_PREFIX_ADDRESS, 32, 1,
req_ctx->decryption_tag,
- AES_BLOCK_SIZE, true);
+ authsize, true);
result = -EBADMSG;
}
The implementation assumed that the client always wants the whole 16 byte AES-GCM tag. Now we respect the requested authentication tag size fetched using crypto_aead_authsize(). Signed-off-by: Lars Persson <larper@axis.com> --- drivers/crypto/axis/artpec6_crypto.c | 35 +++++++++++++++++++++++++---------- 1 file changed, 25 insertions(+), 10 deletions(-)