mirror of
https://github.com/torvalds/linux
synced 2024-11-05 18:23:50 +00:00
11b8d5ef91
To reduce the number of copies of boilerplate code throughout the tree, this patch implements generic glue for the SHA-256 algorithm. This allows a specific arch or hardware implementation to only implement the special handling that it needs. The users need to supply an implementation of void (sha256_block_fn)(struct sha256_state *sst, u8 const *src, int blocks) and pass it to the SHA-256 base functions. For easy casting between the prototype above and existing block functions that take a 'u32 state[]' as their first argument, the 'state' member of struct sha256_state is moved to the base of the struct. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
128 lines
3 KiB
C
128 lines
3 KiB
C
/*
|
|
* sha256_base.h - core logic for SHA-256 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 (sha256_block_fn)(struct sha256_state *sst, u8 const *src,
|
|
int blocks);
|
|
|
|
static inline int sha224_base_init(struct shash_desc *desc)
|
|
{
|
|
struct sha256_state *sctx = shash_desc_ctx(desc);
|
|
|
|
sctx->state[0] = SHA224_H0;
|
|
sctx->state[1] = SHA224_H1;
|
|
sctx->state[2] = SHA224_H2;
|
|
sctx->state[3] = SHA224_H3;
|
|
sctx->state[4] = SHA224_H4;
|
|
sctx->state[5] = SHA224_H5;
|
|
sctx->state[6] = SHA224_H6;
|
|
sctx->state[7] = SHA224_H7;
|
|
sctx->count = 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static inline int sha256_base_init(struct shash_desc *desc)
|
|
{
|
|
struct sha256_state *sctx = shash_desc_ctx(desc);
|
|
|
|
sctx->state[0] = SHA256_H0;
|
|
sctx->state[1] = SHA256_H1;
|
|
sctx->state[2] = SHA256_H2;
|
|
sctx->state[3] = SHA256_H3;
|
|
sctx->state[4] = SHA256_H4;
|
|
sctx->state[5] = SHA256_H5;
|
|
sctx->state[6] = SHA256_H6;
|
|
sctx->state[7] = SHA256_H7;
|
|
sctx->count = 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static inline int sha256_base_do_update(struct shash_desc *desc,
|
|
const u8 *data,
|
|
unsigned int len,
|
|
sha256_block_fn *block_fn)
|
|
{
|
|
struct sha256_state *sctx = shash_desc_ctx(desc);
|
|
unsigned int partial = sctx->count % SHA256_BLOCK_SIZE;
|
|
|
|
sctx->count += len;
|
|
|
|
if (unlikely((partial + len) >= SHA256_BLOCK_SIZE)) {
|
|
int blocks;
|
|
|
|
if (partial) {
|
|
int p = SHA256_BLOCK_SIZE - partial;
|
|
|
|
memcpy(sctx->buf + partial, data, p);
|
|
data += p;
|
|
len -= p;
|
|
|
|
block_fn(sctx, sctx->buf, 1);
|
|
}
|
|
|
|
blocks = len / SHA256_BLOCK_SIZE;
|
|
len %= SHA256_BLOCK_SIZE;
|
|
|
|
if (blocks) {
|
|
block_fn(sctx, data, blocks);
|
|
data += blocks * SHA256_BLOCK_SIZE;
|
|
}
|
|
partial = 0;
|
|
}
|
|
if (len)
|
|
memcpy(sctx->buf + partial, data, len);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static inline int sha256_base_do_finalize(struct shash_desc *desc,
|
|
sha256_block_fn *block_fn)
|
|
{
|
|
const int bit_offset = SHA256_BLOCK_SIZE - sizeof(__be64);
|
|
struct sha256_state *sctx = shash_desc_ctx(desc);
|
|
__be64 *bits = (__be64 *)(sctx->buf + bit_offset);
|
|
unsigned int partial = sctx->count % SHA256_BLOCK_SIZE;
|
|
|
|
sctx->buf[partial++] = 0x80;
|
|
if (partial > bit_offset) {
|
|
memset(sctx->buf + partial, 0x0, SHA256_BLOCK_SIZE - partial);
|
|
partial = 0;
|
|
|
|
block_fn(sctx, sctx->buf, 1);
|
|
}
|
|
|
|
memset(sctx->buf + partial, 0x0, bit_offset - partial);
|
|
*bits = cpu_to_be64(sctx->count << 3);
|
|
block_fn(sctx, sctx->buf, 1);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static inline int sha256_base_finish(struct shash_desc *desc, u8 *out)
|
|
{
|
|
unsigned int digest_size = crypto_shash_digestsize(desc->tfm);
|
|
struct sha256_state *sctx = shash_desc_ctx(desc);
|
|
__be32 *digest = (__be32 *)out;
|
|
int i;
|
|
|
|
for (i = 0; digest_size > 0; i++, digest_size -= sizeof(__be32))
|
|
put_unaligned_be32(sctx->state[i], digest++);
|
|
|
|
*sctx = (struct sha256_state){};
|
|
return 0;
|
|
}
|