crypto: mxs-dcp: Fix AES-CBC with hardware-bound keys

Commit Message

Tomas Paukrt Sept. 13, 2024, 9:11 a.m. UTC

Fix passing an initialization vector in the payload field which
is necessary for AES in CBC mode even with hardware-bound keys.

Fixes: 3d16af0b4cfa ("crypto: mxs-dcp: Add support for hardware-bound keys")
Signed-off-by: Tomas Paukrt <[e-mail]>
---
 drivers/crypto/mxs-dcp.c | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

Patch

diff --git a/drivers/crypto/mxs-dcp.c b/drivers/crypto/mxs-dcp.c
index c82775d..77a6301 100644
--- a/drivers/crypto/mxs-dcp.c
+++ b/drivers/crypto/mxs-dcp.c
@@ -225,21 +225,22 @@  static int mxs_dcp_start_dma(struct dcp_async_ctx *actx)
 static int mxs_dcp_run_aes(struct dcp_async_ctx *actx,
 			   struct skcipher_request *req, int init)
 {
-	dma_addr_t key_phys = 0;
-	dma_addr_t src_phys, dst_phys;
+	dma_addr_t key_phys, src_phys, dst_phys;
 	struct dcp *sdcp = global_sdcp;
 	struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
 	struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req);
 	bool key_referenced = actx->key_referenced;
 	int ret;
 
-	if (!key_referenced) {
+	if (key_referenced)
+		key_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_key + AES_KEYSIZE_128,
+					  AES_KEYSIZE_128, DMA_TO_DEVICE);
+	else
 		key_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_key,
 					  2 * AES_KEYSIZE_128, DMA_TO_DEVICE);
-		ret = dma_mapping_error(sdcp->dev, key_phys);
-		if (ret)
-			return ret;
-	}
+	ret = dma_mapping_error(sdcp->dev, key_phys);
+	if (ret)
+		return ret;
 
 	src_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_in_buf,
 				  DCP_BUF_SZ, DMA_TO_DEVICE);
@@ -300,7 +301,10 @@  static int mxs_dcp_run_aes(struct dcp_async_ctx *actx,
 err_dst:
 	dma_unmap_single(sdcp->dev, src_phys, DCP_BUF_SZ, DMA_TO_DEVICE);
 err_src:
-	if (!key_referenced)
+	if (key_referenced)
+		dma_unmap_single(sdcp->dev, key_phys, AES_KEYSIZE_128,
+				 DMA_TO_DEVICE);
+	else
 		dma_unmap_single(sdcp->dev, key_phys, 2 * AES_KEYSIZE_128,
 				 DMA_TO_DEVICE);
 	return ret;