crypto: sha256_generic - Use 64-bit counter like sha1

This patch replaces the two 32-bit counter code in sha256_generic
with the simpler 64-bit counter code from sha1.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Herbert Xu 2009-07-10 12:54:20 +08:00
parent e2a7ce4e18
commit 3d4d277cf8

View file

@ -26,7 +26,7 @@
#include <asm/byteorder.h>
struct sha256_ctx {
u32 count[2];
u64 count;
u32 state[8];
u8 buf[128];
};
@ -231,8 +231,7 @@ static int sha224_init(struct shash_desc *desc)
sctx->state[5] = SHA224_H5;
sctx->state[6] = SHA224_H6;
sctx->state[7] = SHA224_H7;
sctx->count[0] = 0;
sctx->count[1] = 0;
sctx->count = 0;
return 0;
}
@ -248,7 +247,7 @@ static int sha256_init(struct shash_desc *desc)
sctx->state[5] = SHA256_H5;
sctx->state[6] = SHA256_H6;
sctx->state[7] = SHA256_H7;
sctx->count[0] = sctx->count[1] = 0;
sctx->count = 0;
return 0;
}
@ -257,33 +256,30 @@ static int sha256_update(struct shash_desc *desc, const u8 *data,
unsigned int len)
{
struct sha256_ctx *sctx = shash_desc_ctx(desc);
unsigned int i, index, part_len;
unsigned int partial, done;
const u8 *src;
/* Compute number of bytes mod 128 */
index = (unsigned int)((sctx->count[0] >> 3) & 0x3f);
partial = sctx->count & 0x3f;
sctx->count += len;
done = 0;
src = data;
/* Update number of bits */
if ((sctx->count[0] += (len << 3)) < (len << 3)) {
sctx->count[1]++;
sctx->count[1] += (len >> 29);
if ((partial + len) > 63) {
if (partial) {
done = -partial;
memcpy(sctx->buf + partial, data, done + 64);
src = sctx->buf;
}
do {
sha256_transform(sctx->state, src);
done += 64;
src = data + done;
} while (done + 63 < len);
partial = 0;
}
part_len = 64 - index;
/* Transform as many times as possible. */
if (len >= part_len) {
memcpy(&sctx->buf[index], data, part_len);
sha256_transform(sctx->state, sctx->buf);
for (i = part_len; i + 63 < len; i += 64)
sha256_transform(sctx->state, &data[i]);
index = 0;
} else {
i = 0;
}
/* Buffer remaining input */
memcpy(&sctx->buf[index], &data[i], len-i);
memcpy(sctx->buf + partial, src, len - done);
return 0;
}
@ -292,22 +288,21 @@ static int sha256_final(struct shash_desc *desc, u8 *out)
{
struct sha256_ctx *sctx = shash_desc_ctx(desc);
__be32 *dst = (__be32 *)out;
__be32 bits[2];
__be64 bits;
unsigned int index, pad_len;
int i;
static const u8 padding[64] = { 0x80, };
/* Save number of bits */
bits[1] = cpu_to_be32(sctx->count[0]);
bits[0] = cpu_to_be32(sctx->count[1]);
bits = cpu_to_be64(sctx->count << 3);
/* Pad out to 56 mod 64. */
index = (sctx->count[0] >> 3) & 0x3f;
index = sctx->count & 0x3f;
pad_len = (index < 56) ? (56 - index) : ((64+56) - index);
sha256_update(desc, padding, pad_len);
/* Append length (before padding) */
sha256_update(desc, (const u8 *)bits, sizeof(bits));
sha256_update(desc, (const u8 *)&bits, sizeof(bits));
/* Store state in digest */
for (i = 0; i < 8; i++)