[PATCH] crypto: sha1: modify sha1_update to use SHA1_BLOCK_SIZE

From: Mandeep Singh Baines
Date: Wed May 25 2011 - 23:11:46 EST


Plus some other minor cleanup.

Signed-off-by: Mandeep Singh Baines <msb@xxxxxxxxxxxx>
Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Cc: David S. Miller <davem@xxxxxxxxxxxxx>
Cc: linux-crypto@xxxxxxxxxxxxxxx
---
crypto/sha1_generic.c | 39 +++++++++++++++++++--------------------
1 files changed, 19 insertions(+), 20 deletions(-)

diff --git a/crypto/sha1_generic.c b/crypto/sha1_generic.c
index 0416091..4bdd228 100644
--- a/crypto/sha1_generic.c
+++ b/crypto/sha1_generic.c
@@ -40,33 +40,32 @@ static int sha1_update(struct shash_desc *desc, const u8 *data,
unsigned int len)
{
struct sha1_state *sctx = shash_desc_ctx(desc);
- unsigned int partial, done;
- const u8 *src;
+ unsigned int partial = sctx->count % SHA1_BLOCK_SIZE;
+ u32 temp[SHA_WORKSPACE_WORDS];
+ const u8 *src = data;

- partial = sctx->count & 0x3f;
sctx->count += len;
- done = 0;
- src = data;

- if ((partial + len) > 63) {
- u32 temp[SHA_WORKSPACE_WORDS];
+ if (partial && ((partial + len) >= SHA1_BLOCK_SIZE)) {
+ unsigned int done = SHA1_BLOCK_SIZE - partial;

- if (partial) {
- done = -partial;
- memcpy(sctx->buffer + partial, data, done + 64);
- src = sctx->buffer;
- }
+ memcpy(sctx->buffer + partial, src, done);
+ sha_transform(sctx->state, sctx->buffer, temp);
+ len -= done;
+ src += done;
+ partial = 0;
+ }

- do {
- sha_transform(sctx->state, src, temp);
- done += 64;
- src = data + done;
- } while (done + 63 < len);
+ while (len >= SHA1_BLOCK_SIZE) {
+ sha_transform(sctx->state, src, temp);
+ len -= SHA1_BLOCK_SIZE;
+ src += SHA1_BLOCK_SIZE;
+ }

+ if (src != data)
memset(temp, 0, sizeof(temp));
- partial = 0;
- }
- memcpy(sctx->buffer + partial, src, len - done);
+
+ memcpy(sctx->buffer + partial, src, len);

return 0;
}
--
1.7.3.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/