[PATCH] s390: sha256 crypto code fix

Fix processing of messages larger than 2 * SHA256_BLOCK_SIZE.

Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/arch/s390/crypto/sha256_s390.c b/arch/s390/crypto/sha256_s390.c
index b75bdbd476c7384c2dbc891964ee8e9c52f2b117..1ec5e92b34544a360126717d233394c524c2643f 100644 (file)
--- a/arch/s390/crypto/sha256_s390.c
+++ b/arch/s390/crypto/sha256_s390.c
@@ -51,6 +51,7 @@ static void sha256_update(void *ctx, const u8 *data, unsigned int len)
 {
        struct s390_sha256_ctx *sctx = ctx;
        unsigned int index;
+       int ret;
 
        /* how much is already in the buffer? */
        index = sctx->count / 8 & 0x3f;
@@ -58,15 +59,29 @@ static void sha256_update(void *ctx, const u8 *data, unsigned int len)
        /* update message bit length */
        sctx->count += len * 8;
 
-       /* process one block */
-       if ((index + len) >= SHA256_BLOCK_SIZE) {
+       if ((index + len) < SHA256_BLOCK_SIZE)
+               goto store;
+
+       /* process one stored block */
+       if (index) {
                memcpy(sctx->buf + index, data, SHA256_BLOCK_SIZE - index);
-               crypt_s390_kimd(KIMD_SHA_256, sctx->state, sctx->buf,
-                               SHA256_BLOCK_SIZE);
+               ret = crypt_s390_kimd(KIMD_SHA_256, sctx->state, sctx->buf,
+                                     SHA256_BLOCK_SIZE);
+               BUG_ON(ret != SHA256_BLOCK_SIZE);
                data += SHA256_BLOCK_SIZE - index;
                len -= SHA256_BLOCK_SIZE - index;
        }
 
+       /* process as many blocks as possible */
+       if (len >= SHA256_BLOCK_SIZE) {
+               ret = crypt_s390_kimd(KIMD_SHA_256, sctx->state, data,
+                                     len & ~(SHA256_BLOCK_SIZE - 1));
+               BUG_ON(ret != (len & ~(SHA256_BLOCK_SIZE - 1)));
+               data += ret;
+               len -= ret;
+       }
+
+store:
        /* anything left? */
        if (len)
                memcpy(sctx->buf + index , data, len);
@@ -119,9 +134,9 @@ static struct crypto_alg alg = {
        .cra_list       =       LIST_HEAD_INIT(alg.cra_list),
        .cra_u          =       { .digest = {
        .dia_digestsize =       SHA256_DIGEST_SIZE,
-       .dia_init       =       sha256_init,
-       .dia_update     =       sha256_update,
-       .dia_final      =       sha256_final } }
+       .dia_init       =       sha256_init,
+       .dia_update     =       sha256_update,
+       .dia_final      =       sha256_final } }
 };
 
 static int init(void)