linux/arch/arm/crypto/sha2-ce-glue.c
Ard Biesheuvel 006d0624fa crypto: arm - add support for SHA-224/256 using ARMv8 Crypto Extensions
This implements the SHA-224/256 secure hash algorithm using the AArch32
versions of the ARMv8 Crypto Extensions for SHA2.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-03-12 21:13:35 +11:00

204 lines
4.7 KiB
C

/*
* sha2-ce-glue.c - SHA-224/SHA-256 using ARMv8 Crypto Extensions
*
* 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/hwcap.h>
#include <asm/simd.h>
#include <asm/neon.h>
#include <asm/unaligned.h>
MODULE_DESCRIPTION("SHA-224/SHA-256 secure hash using ARMv8 Crypto Extensions");
MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
MODULE_LICENSE("GPL v2");
asmlinkage void sha2_ce_transform(int blocks, u8 const *src, u32 *state,
u8 *head);
static int sha224_init(struct shash_desc *desc)
{
struct sha256_state *sctx = shash_desc_ctx(desc);
*sctx = (struct sha256_state){
.state = {
SHA224_H0, SHA224_H1, SHA224_H2, SHA224_H3,
SHA224_H4, SHA224_H5, SHA224_H6, SHA224_H7,
}
};
return 0;
}
static int sha256_init(struct shash_desc *desc)
{
struct sha256_state *sctx = shash_desc_ctx(desc);
*sctx = (struct sha256_state){
.state = {
SHA256_H0, SHA256_H1, SHA256_H2, SHA256_H3,
SHA256_H4, SHA256_H5, SHA256_H6, SHA256_H7,
}
};
return 0;
}
static int sha2_update(struct shash_desc *desc, const u8 *data,
unsigned int len)
{
struct sha256_state *sctx = shash_desc_ctx(desc);
unsigned int partial;
if (!may_use_simd())
return crypto_sha256_update(desc, data, len);
partial = sctx->count % SHA256_BLOCK_SIZE;
sctx->count += len;
if ((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;
}
blocks = len / SHA256_BLOCK_SIZE;
len %= SHA256_BLOCK_SIZE;
kernel_neon_begin();
sha2_ce_transform(blocks, data, sctx->state,
partial ? sctx->buf : NULL);
kernel_neon_end();
data += blocks * SHA256_BLOCK_SIZE;
partial = 0;
}
if (len)
memcpy(sctx->buf + partial, data, len);
return 0;
}
static void sha2_final(struct shash_desc *desc)
{
static const u8 padding[SHA256_BLOCK_SIZE] = { 0x80, };
struct sha256_state *sctx = shash_desc_ctx(desc);
__be64 bits = cpu_to_be64(sctx->count << 3);
u32 padlen = SHA256_BLOCK_SIZE
- ((sctx->count + sizeof(bits)) % SHA256_BLOCK_SIZE);
sha2_update(desc, padding, padlen);
sha2_update(desc, (const u8 *)&bits, sizeof(bits));
}
static int sha224_final(struct shash_desc *desc, u8 *out)
{
struct sha256_state *sctx = shash_desc_ctx(desc);
__be32 *dst = (__be32 *)out;
int i;
sha2_final(desc);
for (i = 0; i < SHA224_DIGEST_SIZE / sizeof(__be32); i++)
put_unaligned_be32(sctx->state[i], dst++);
*sctx = (struct sha256_state){};
return 0;
}
static int sha256_final(struct shash_desc *desc, u8 *out)
{
struct sha256_state *sctx = shash_desc_ctx(desc);
__be32 *dst = (__be32 *)out;
int i;
sha2_final(desc);
for (i = 0; i < SHA256_DIGEST_SIZE / sizeof(__be32); i++)
put_unaligned_be32(sctx->state[i], dst++);
*sctx = (struct sha256_state){};
return 0;
}
static int sha2_export(struct shash_desc *desc, void *out)
{
struct sha256_state *sctx = shash_desc_ctx(desc);
struct sha256_state *dst = out;
*dst = *sctx;
return 0;
}
static int sha2_import(struct shash_desc *desc, const void *in)
{
struct sha256_state *sctx = shash_desc_ctx(desc);
struct sha256_state const *src = in;
*sctx = *src;
return 0;
}
static struct shash_alg algs[] = { {
.init = sha224_init,
.update = sha2_update,
.final = sha224_final,
.export = sha2_export,
.import = sha2_import,
.descsize = sizeof(struct sha256_state),
.digestsize = SHA224_DIGEST_SIZE,
.statesize = sizeof(struct sha256_state),
.base = {
.cra_name = "sha224",
.cra_driver_name = "sha224-ce",
.cra_priority = 200,
.cra_flags = CRYPTO_ALG_TYPE_SHASH,
.cra_blocksize = SHA256_BLOCK_SIZE,
.cra_module = THIS_MODULE,
}
}, {
.init = sha256_init,
.update = sha2_update,
.final = sha256_final,
.export = sha2_export,
.import = sha2_import,
.descsize = sizeof(struct sha256_state),
.digestsize = SHA256_DIGEST_SIZE,
.statesize = sizeof(struct sha256_state),
.base = {
.cra_name = "sha256",
.cra_driver_name = "sha256-ce",
.cra_priority = 200,
.cra_flags = CRYPTO_ALG_TYPE_SHASH,
.cra_blocksize = SHA256_BLOCK_SIZE,
.cra_module = THIS_MODULE,
}
} };
static int __init sha2_ce_mod_init(void)
{
if (!(elf_hwcap2 & HWCAP2_SHA2))
return -ENODEV;
return crypto_register_shashes(algs, ARRAY_SIZE(algs));
}
static void __exit sha2_ce_mod_fini(void)
{
crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
}
module_init(sha2_ce_mod_init);
module_exit(sha2_ce_mod_fini);