crypto: atmel-aes - properly set IV after {en,de}crypt

Certain cipher modes like CTS expect the IV (req->info) of
ablkcipher_request (or equivalently req->iv of skcipher_request) to
contain the last ciphertext block when the {en,de}crypt operation is done.

Fix this issue for the Atmel AES hardware engine. The tcrypt test
case for cts(cbc(aes)) is now correctly passed.

In the case of in-place decryption, copy the ciphertext in an
intermediate buffer before decryption.

Signed-off-by: Romain Izard <romain.izard.pro@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Romain Izard 2017-10-31 16:25:23 +01:00 committed by Herbert Xu
parent 142a27f0a7
commit 91308019ec

View File

@ -111,6 +111,7 @@ struct atmel_aes_base_ctx {
int keylen;
u32 key[AES_KEYSIZE_256 / sizeof(u32)];
u16 block_size;
bool is_aead;
};
struct atmel_aes_ctx {
@ -157,6 +158,7 @@ struct atmel_aes_authenc_ctx {
struct atmel_aes_reqctx {
unsigned long mode;
u32 lastc[AES_BLOCK_SIZE / sizeof(u32)];
};
#ifdef CONFIG_CRYPTO_DEV_ATMEL_AUTHENC
@ -498,12 +500,34 @@ static void atmel_aes_authenc_complete(struct atmel_aes_dev *dd, int err);
static inline int atmel_aes_complete(struct atmel_aes_dev *dd, int err)
{
#ifdef CONFIG_CRYPTO_DEV_ATMEL_AUTHENC
atmel_aes_authenc_complete(dd, err);
if (dd->ctx->is_aead)
atmel_aes_authenc_complete(dd, err);
#endif
clk_disable(dd->iclk);
dd->flags &= ~AES_FLAGS_BUSY;
if (!dd->ctx->is_aead) {
struct ablkcipher_request *req =
ablkcipher_request_cast(dd->areq);
struct atmel_aes_reqctx *rctx = ablkcipher_request_ctx(req);
struct crypto_ablkcipher *ablkcipher =
crypto_ablkcipher_reqtfm(req);
int ivsize = crypto_ablkcipher_ivsize(ablkcipher);
if (rctx->mode & AES_FLAGS_ENCRYPT) {
scatterwalk_map_and_copy(req->info, req->dst,
req->nbytes - ivsize, ivsize, 0);
} else {
if (req->src == req->dst) {
memcpy(req->info, rctx->lastc, ivsize);
} else {
scatterwalk_map_and_copy(req->info, req->src,
req->nbytes - ivsize, ivsize, 0);
}
}
}
if (dd->is_async)
dd->areq->complete(dd->areq, err);
@ -1072,11 +1096,11 @@ static int atmel_aes_ctr_start(struct atmel_aes_dev *dd)
static int atmel_aes_crypt(struct ablkcipher_request *req, unsigned long mode)
{
struct atmel_aes_base_ctx *ctx;
struct crypto_ablkcipher *ablkcipher = crypto_ablkcipher_reqtfm(req);
struct atmel_aes_base_ctx *ctx = crypto_ablkcipher_ctx(ablkcipher);
struct atmel_aes_reqctx *rctx;
struct atmel_aes_dev *dd;
ctx = crypto_ablkcipher_ctx(crypto_ablkcipher_reqtfm(req));
switch (mode & AES_FLAGS_OPMODE_MASK) {
case AES_FLAGS_CFB8:
ctx->block_size = CFB8_BLOCK_SIZE;
@ -1098,6 +1122,7 @@ static int atmel_aes_crypt(struct ablkcipher_request *req, unsigned long mode)
ctx->block_size = AES_BLOCK_SIZE;
break;
}
ctx->is_aead = false;
dd = atmel_aes_find_dev(ctx);
if (!dd)
@ -1106,6 +1131,13 @@ static int atmel_aes_crypt(struct ablkcipher_request *req, unsigned long mode)
rctx = ablkcipher_request_ctx(req);
rctx->mode = mode;
if (!(mode & AES_FLAGS_ENCRYPT) && (req->src == req->dst)) {
int ivsize = crypto_ablkcipher_ivsize(ablkcipher);
scatterwalk_map_and_copy(rctx->lastc, req->src,
(req->nbytes - ivsize), ivsize, 0);
}
return atmel_aes_handle_queue(dd, &req->base);
}
@ -1740,6 +1772,7 @@ static int atmel_aes_gcm_crypt(struct aead_request *req,
ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
ctx->block_size = AES_BLOCK_SIZE;
ctx->is_aead = true;
dd = atmel_aes_find_dev(ctx);
if (!dd)
@ -2224,6 +2257,7 @@ static int atmel_aes_authenc_crypt(struct aead_request *req,
rctx->base.mode = mode;
ctx->block_size = AES_BLOCK_SIZE;
ctx->is_aead = true;
dd = atmel_aes_find_dev(ctx);
if (!dd)