[PATCH 3/3] crypto: stm32/cryp - update to return iv_out

[Lionel Debieve]

The kernel crypto API request output the next IV data to
IV buffer for CBC implementation.

Signed-off-by: Lionel Debieve <lionel.debieve@xxxxxx>
---
 drivers/crypto/stm32/stm32-cryp.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/drivers/crypto/stm32/stm32-cryp.c b/drivers/crypto/stm32/stm32-cryp.c
index eb525669..cddcc97 100644
--- a/drivers/crypto/stm32/stm32-cryp.c
+++ b/drivers/crypto/stm32/stm32-cryp.c
@@ -393,6 +393,23 @@ static void stm32_cryp_hw_write_iv(struct stm32_cryp *cryp, u32 *iv)
 	}
 }
 
+static void stm32_cryp_get_iv(struct stm32_cryp *cryp)
+{
+	struct ablkcipher_request *req = cryp->req;
+	u32 *tmp = req->info;
+
+	if (!tmp)
+		return;
+
+	*tmp++ = cpu_to_be32(stm32_cryp_read(cryp, CRYP_IV0LR));
+	*tmp++ = cpu_to_be32(stm32_cryp_read(cryp, CRYP_IV0RR));
+
+	if (is_aes(cryp)) {
+		*tmp++ = cpu_to_be32(stm32_cryp_read(cryp, CRYP_IV1LR));
+		*tmp++ = cpu_to_be32(stm32_cryp_read(cryp, CRYP_IV1RR));
+	}
+}
+
 static void stm32_cryp_hw_write_key(struct stm32_cryp *c)
 {
 	unsigned int i;
@@ -622,6 +639,9 @@ static void stm32_cryp_finish_req(struct stm32_cryp *cryp, int err)
 		/* Phase 4 : output tag */
 		err = stm32_cryp_read_auth_tag(cryp);
 
+	if (!err && (!(is_gcm(cryp) || is_ccm(cryp))))
+		stm32_cryp_get_iv(cryp);
+
 	if (cryp->sgs_copied) {
 		void *buf_in, *buf_out;
 		int pages, len;
-- 
2.7.4