[S390] crypto: cleanup.

Cleanup code and remove obsolete documentation.

Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 16 insertions, 22 deletions

diff --git a/arch/s390/crypto/sha256_s390.c b/arch/s390/crypto/sha256_s390.c
index 78436c696d37..2ced3330bce0 100644
--- a/arch/s390/crypto/sha256_s390.c
+++ b/arch/s390/crypto/sha256_s390.c
@@ -26,7 +26,7 @@
 #define SHA256_BLOCK_SIZE       64
 
 struct s390_sha256_ctx {
-        u64 count;
+        u64 count;              /* message length */
         u32 state[8];
         u8 buf[2 * SHA256_BLOCK_SIZE];
 };
@@ -54,10 +54,9 @@ static void sha256_update(struct crypto_tfm *tfm, const u8 *data,
         int ret;
 
         /* how much is already in the buffer? */
-        index = sctx->count / 8 & 0x3f;
+        index = sctx->count & 0x3f;
 
-        /* update message bit length */
-        sctx->count += len * 8;
+        sctx->count += len;
 
         if ((index + len) < SHA256_BLOCK_SIZE)
                 goto store;
@@ -87,12 +86,17 @@ store:
                 memcpy(sctx->buf + index , data, len);
 }
 
-static void pad_message(struct s390_sha256_ctx* sctx)
+/* Add padding and return the message digest */
+static void sha256_final(struct crypto_tfm *tfm, u8 *out)
 {
-        int index, end;
+        struct s390_sha256_ctx *sctx = crypto_tfm_ctx(tfm);
+        u64 bits;
+        unsigned int index, end;
+        int ret;
 
-        index = sctx->count / 8 & 0x3f;
-        end = index < 56 ? SHA256_BLOCK_SIZE : 2 * SHA256_BLOCK_SIZE;
+        /* must perform manual padding */
+        index = sctx->count & 0x3f;
+        end = (index < 56) ? SHA256_BLOCK_SIZE : (2 * SHA256_BLOCK_SIZE);
 
         /* start pad with 1 */
         sctx->buf[index] = 0x80;
@@ -102,21 +106,11 @@ static void pad_message(struct s390_sha256_ctx* sctx)
         memset(sctx->buf + index, 0x00, end - index - 8);
 
         /* append message length */
-        memcpy(sctx->buf + end - 8, &sctx->count, sizeof sctx->count);
-
-        sctx->count = end * 8;
-}
-
-/* Add padding and return the message digest */
-static void sha256_final(struct crypto_tfm *tfm, u8 *out)
-{
-        struct s390_sha256_ctx *sctx = crypto_tfm_ctx(tfm);
-
-        /* must perform manual padding */
-        pad_message(sctx);
+        bits = sctx->count * 8;
+        memcpy(sctx->buf + end - 8, &bits, sizeof(bits));
 
-        crypt_s390_kimd(KIMD_SHA_256, sctx->state, sctx->buf,
-                        sctx->count / 8);
+        ret = crypt_s390_kimd(KIMD_SHA_256, sctx->state, sctx->buf, end);
+        BUG_ON(ret != end);
 
         /* copy digest to out */
         memcpy(out, sctx->state, SHA256_DIGEST_SIZE);