This patch adds mtk_aes_gcm_tag_verify() which is used to compare
authenticated tag.
Signed-off-by: Ryder Lee <ryder....@mediatek.com>
---
drivers/crypto/mediatek/mtk-aes.c | 24 ++++++++++++++++++++++--
drivers/crypto/mediatek/mtk-platform.h | 2 ++
2 files changed, 24 insertions(+), 2 deletions(-)
diff --git a/drivers/crypto/mediatek/mtk-aes.c
b/drivers/crypto/mediatek/mtk-aes.c
index 6a0180d..8f3efa5 100644
--- a/drivers/crypto/mediatek/mtk-aes.c
+++ b/drivers/crypto/mediatek/mtk-aes.c
@@ -70,6 +70,8 @@
#define AES_FLAGS_ENCRYPT BIT(4)
#define AES_FLAGS_BUSY BIT(5)
+#define AES_AUTH_TAG_ERR cpu_to_le32(BIT(26))
+
/**
* Command token(CT) is a set of hardware instructions that
* are used to control engine's processing flow of AES.
@@ -306,6 +308,9 @@ static int mtk_aes_xmit(struct mtk_cryp *cryp, struct
mtk_aes_rec *aes)
}
res->hdr |= MTK_DESC_LAST;
+ /* Pointer to current result descriptor */
+ ring->res_prev = res;
+
/* Prepare enough space for authenticated tag */
if (aes->flags & AES_FLAGS_GCM)
res->hdr += AES_BLOCK_SIZE;
@@ -799,6 +804,19 @@ static int mtk_aes_ctr_cra_init(struct crypto_tfm *tfm)
return container_of(ctx, struct mtk_aes_gcm_ctx, base);
}
+/*
+ * Engine will verify and compare tag automatically, so we just need
+ * to check returned status which stored in the result descriptor.
+ */
+static int mtk_aes_gcm_tag_verify(struct mtk_cryp *cryp,
+ struct mtk_aes_rec *aes)
+{
+ u32 status = cryp->ring[aes->id]->res_prev->ct;
+
+ return mtk_aes_complete(cryp, aes, (status & AES_AUTH_TAG_ERR) ?
+ -EBADMSG : 0);
+}
+
/* Initialize transform information of GCM mode */
static void mtk_aes_gcm_info_init(struct mtk_cryp *cryp,
struct mtk_aes_rec *aes,
@@ -902,6 +920,8 @@ static int mtk_aes_gcm_start(struct mtk_cryp *cryp, struct
mtk_aes_rec *aes)
if (aes->flags & AES_FLAGS_ENCRYPT) {
u32 tag[4];
+
+ aes->resume = mtk_aes_transfer_complete;
/* Compute total process length. */
aes->total = len + gctx->authsize;
/* Compute text length. */
@@ -909,10 +929,10 @@ static int mtk_aes_gcm_start(struct mtk_cryp *cryp,
struct mtk_aes_rec *aes)
/* Hardware will append authenticated tag to output buffer */
scatterwalk_map_and_copy(tag, req->dst, len, gctx->authsize, 1);
} else {
+ aes->resume = mtk_aes_gcm_tag_verify;
aes->total = len;
gctx->textlen = req->cryptlen - gctx->authsize;
}
- aes->resume = mtk_aes_transfer_complete;
return mtk_aes_gcm_dma(cryp, aes, req->src, req->dst, len);
}
@@ -925,7 +945,7 @@ static int mtk_aes_gcm_crypt(struct aead_request *req, u64
mode)
rctx->mode = AES_FLAGS_GCM | mode;
return mtk_aes_handle_queue(ctx->cryp, !!(mode & AES_FLAGS_ENCRYPT),
- &req->base);
+ &req->base);
}
static void mtk_gcm_setkey_done(struct crypto_async_request *req, int err)
diff --git a/drivers/crypto/mediatek/mtk-platform.h
b/drivers/crypto/mediatek/mtk-platform.h
index cc98c2c..303c152 100644
--- a/drivers/crypto/mediatek/mtk-platform.h
+++ b/drivers/crypto/mediatek/mtk-platform.h
@@ -88,6 +88,7 @@ struct mtk_desc {
* @cmd_dma: DMA address of command descriptor ring
* @res_base: pointer to result descriptor ring base
* @res_next: pointer to the next result descriptor
+ * @res_prev: pointer to the previous result descriptor
* @res_dma: DMA address of result descriptor ring
*
* A descriptor ring is a circular buffer that is used to manage
@@ -100,6 +101,7 @@ struct mtk_ring {
dma_addr_t cmd_dma;
struct mtk_desc *res_base;
struct mtk_desc *res_next;
+ struct mtk_desc *res_prev;
dma_addr_t res_dma;
};
--
1.9.1
