https://github.com/torvalds/linux
Tip revision: 9f9499ae8e6415cefc4fe0a96ad0e27864353c89 authored by Linus Torvalds on 14 December 2015, 01:42:58 UTC
Linux 4.4-rc5
Linux 4.4-rc5
Tip revision: 9f9499a
sha1_base.h
/*
* sha1_base.h - core logic for SHA-1 implementations
*
* Copyright (C) 2015 Linaro Ltd <ard.biesheuvel@linaro.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <crypto/internal/hash.h>
#include <crypto/sha.h>
#include <linux/crypto.h>
#include <linux/module.h>
#include <asm/unaligned.h>
typedef void (sha1_block_fn)(struct sha1_state *sst, u8 const *src, int blocks);
static inline int sha1_base_init(struct shash_desc *desc)
{
struct sha1_state *sctx = shash_desc_ctx(desc);
sctx->state[0] = SHA1_H0;
sctx->state[1] = SHA1_H1;
sctx->state[2] = SHA1_H2;
sctx->state[3] = SHA1_H3;
sctx->state[4] = SHA1_H4;
sctx->count = 0;
return 0;
}
static inline int sha1_base_do_update(struct shash_desc *desc,
const u8 *data,
unsigned int len,
sha1_block_fn *block_fn)
{
struct sha1_state *sctx = shash_desc_ctx(desc);
unsigned int partial = sctx->count % SHA1_BLOCK_SIZE;
sctx->count += len;
if (unlikely((partial + len) >= SHA1_BLOCK_SIZE)) {
int blocks;
if (partial) {
int p = SHA1_BLOCK_SIZE - partial;
memcpy(sctx->buffer + partial, data, p);
data += p;
len -= p;
block_fn(sctx, sctx->buffer, 1);
}
blocks = len / SHA1_BLOCK_SIZE;
len %= SHA1_BLOCK_SIZE;
if (blocks) {
block_fn(sctx, data, blocks);
data += blocks * SHA1_BLOCK_SIZE;
}
partial = 0;
}
if (len)
memcpy(sctx->buffer + partial, data, len);
return 0;
}
static inline int sha1_base_do_finalize(struct shash_desc *desc,
sha1_block_fn *block_fn)
{
const int bit_offset = SHA1_BLOCK_SIZE - sizeof(__be64);
struct sha1_state *sctx = shash_desc_ctx(desc);
__be64 *bits = (__be64 *)(sctx->buffer + bit_offset);
unsigned int partial = sctx->count % SHA1_BLOCK_SIZE;
sctx->buffer[partial++] = 0x80;
if (partial > bit_offset) {
memset(sctx->buffer + partial, 0x0, SHA1_BLOCK_SIZE - partial);
partial = 0;
block_fn(sctx, sctx->buffer, 1);
}
memset(sctx->buffer + partial, 0x0, bit_offset - partial);
*bits = cpu_to_be64(sctx->count << 3);
block_fn(sctx, sctx->buffer, 1);
return 0;
}
static inline int sha1_base_finish(struct shash_desc *desc, u8 *out)
{
struct sha1_state *sctx = shash_desc_ctx(desc);
__be32 *digest = (__be32 *)out;
int i;
for (i = 0; i < SHA1_DIGEST_SIZE / sizeof(__be32); i++)
put_unaligned_be32(sctx->state[i], digest++);
*sctx = (struct sha1_state){};
return 0;
}