crypto: rockchip - update new iv to device in multiple operations

For chain mode in cipher(eg. AES-CBC/DES-CBC), the iv is continuously
updated in the operation. The new iv value should be written to device
register by software.
Reported-by: Eric Biggers <ebiggers@google.com>
Fixes: 433cd2c6 ("crypto: rockchip - add crypto driver for rk3288")
Cc: <stable@vger.kernel.org> # v4.5+
Signed-off-by: Zhang Zhijie <zhangzj@rock-chips.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/rockchip/rk3288_crypto.h

@@ -245,6 +245,7 @@ struct rk_cipher_ctx {
 	struct rk_crypto_info		*dev;
 	unsigned int			keylen;
 	u32				mode;
+	u8				iv[AES_BLOCK_SIZE];
 };
 
 enum alg_type {

drivers/crypto/rockchip/rk3288_crypto_ablkcipher.c

@@ -242,6 +242,17 @@ static void crypto_dma_start(struct rk_crypto_info *dev)
 static int rk_set_data_start(struct rk_crypto_info *dev)
 {
 	int err;
+	struct ablkcipher_request *req =
+		ablkcipher_request_cast(dev->async_req);
+	struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
+	struct rk_cipher_ctx *ctx = crypto_ablkcipher_ctx(tfm);
+	u32 ivsize = crypto_ablkcipher_ivsize(tfm);
+	u8 *src_last_blk = page_address(sg_page(dev->sg_src)) +
+		dev->sg_src->offset + dev->sg_src->length - ivsize;
+
+	/* store the iv that need to be updated in chain mode */
+	if (ctx->mode & RK_CRYPTO_DEC)
+		memcpy(ctx->iv, src_last_blk, ivsize);
 
 	err = dev->load_data(dev, dev->sg_src, dev->sg_dst);
 	if (!err)
@@ -286,6 +297,28 @@ static void rk_iv_copyback(struct rk_crypto_info *dev)
 		memcpy_fromio(req->info, dev->reg + RK_CRYPTO_AES_IV_0, ivsize);
 }
 
+static void rk_update_iv(struct rk_crypto_info *dev)
+{
+	struct ablkcipher_request *req =
+		ablkcipher_request_cast(dev->async_req);
+	struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
+	struct rk_cipher_ctx *ctx = crypto_ablkcipher_ctx(tfm);
+	u32 ivsize = crypto_ablkcipher_ivsize(tfm);
+	u8 *new_iv = NULL;
+
+	if (ctx->mode & RK_CRYPTO_DEC) {
+		new_iv = ctx->iv;
+	} else {
+		new_iv = page_address(sg_page(dev->sg_dst)) +
+			 dev->sg_dst->offset + dev->sg_dst->length - ivsize;
+	}
+
+	if (ivsize == DES_BLOCK_SIZE)
+		memcpy_toio(dev->reg + RK_CRYPTO_TDES_IV_0, new_iv, ivsize);
+	else if (ivsize == AES_BLOCK_SIZE)
+		memcpy_toio(dev->reg + RK_CRYPTO_AES_IV_0, new_iv, ivsize);
+}
+
 /* return:
  *	true	some err was occurred
  *	fault	no err, continue
@@ -307,6 +340,7 @@ static int rk_ablk_rx(struct rk_crypto_info *dev)
 		}
 	}
 	if (dev->left_bytes) {
+		rk_update_iv(dev);
 		if (dev->aligned) {
 			if (sg_is_last(dev->sg_src)) {
 				dev_err(dev->dev, "[%s:%d] Lack of data\n",