linux/arch/arm64/crypto/sha1-ce-glue.c
Ard Biesheuvel 5a69e1b73d crypto: arm64/sha1-ce - simplify NEON yield
Instead of calling into kernel_neon_end() and kernel_neon_begin() (and
potentially into schedule()) from the assembler code when running in
task mode and a reschedule is pending, perform only the preempt count
check in assembler, but simply return early in this case, and let the C
code deal with the consequences.

This reverts commit 7df8d16475.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2021-02-10 17:55:57 +11:00

148 lines
3.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* sha1-ce-glue.c - SHA-1 secure hash using ARMv8 Crypto Extensions
*
* Copyright (C) 2014 - 2017 Linaro Ltd <ard.biesheuvel@linaro.org>
*/
#include <asm/neon.h>
#include <asm/simd.h>
#include <asm/unaligned.h>
#include <crypto/internal/hash.h>
#include <crypto/internal/simd.h>
#include <crypto/sha1.h>
#include <crypto/sha1_base.h>
#include <linux/cpufeature.h>
#include <linux/crypto.h>
#include <linux/module.h>
MODULE_DESCRIPTION("SHA1 secure hash using ARMv8 Crypto Extensions");
MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS_CRYPTO("sha1");
struct sha1_ce_state {
struct sha1_state sst;
u32 finalize;
};
extern const u32 sha1_ce_offsetof_count;
extern const u32 sha1_ce_offsetof_finalize;
asmlinkage int sha1_ce_transform(struct sha1_ce_state *sst, u8 const *src,
int blocks);
static void __sha1_ce_transform(struct sha1_state *sst, u8 const *src,
int blocks)
{
while (blocks) {
int rem;
kernel_neon_begin();
rem = sha1_ce_transform(container_of(sst, struct sha1_ce_state,
sst), src, blocks);
kernel_neon_end();
src += (blocks - rem) * SHA1_BLOCK_SIZE;
blocks = rem;
}
}
const u32 sha1_ce_offsetof_count = offsetof(struct sha1_ce_state, sst.count);
const u32 sha1_ce_offsetof_finalize = offsetof(struct sha1_ce_state, finalize);
static int sha1_ce_update(struct shash_desc *desc, const u8 *data,
unsigned int len)
{
struct sha1_ce_state *sctx = shash_desc_ctx(desc);
if (!crypto_simd_usable())
return crypto_sha1_update(desc, data, len);
sctx->finalize = 0;
sha1_base_do_update(desc, data, len, __sha1_ce_transform);
return 0;
}
static int sha1_ce_finup(struct shash_desc *desc, const u8 *data,
unsigned int len, u8 *out)
{
struct sha1_ce_state *sctx = shash_desc_ctx(desc);
bool finalize = !sctx->sst.count && !(len % SHA1_BLOCK_SIZE) && len;
if (!crypto_simd_usable())
return crypto_sha1_finup(desc, data, len, out);
/*
* Allow the asm code to perform the finalization if there is no
* partial data and the input is a round multiple of the block size.
*/
sctx->finalize = finalize;
sha1_base_do_update(desc, data, len, __sha1_ce_transform);
if (!finalize)
sha1_base_do_finalize(desc, __sha1_ce_transform);
return sha1_base_finish(desc, out);
}
static int sha1_ce_final(struct shash_desc *desc, u8 *out)
{
struct sha1_ce_state *sctx = shash_desc_ctx(desc);
if (!crypto_simd_usable())
return crypto_sha1_finup(desc, NULL, 0, out);
sctx->finalize = 0;
sha1_base_do_finalize(desc, __sha1_ce_transform);
return sha1_base_finish(desc, out);
}
static int sha1_ce_export(struct shash_desc *desc, void *out)
{
struct sha1_ce_state *sctx = shash_desc_ctx(desc);
memcpy(out, &sctx->sst, sizeof(struct sha1_state));
return 0;
}
static int sha1_ce_import(struct shash_desc *desc, const void *in)
{
struct sha1_ce_state *sctx = shash_desc_ctx(desc);
memcpy(&sctx->sst, in, sizeof(struct sha1_state));
sctx->finalize = 0;
return 0;
}
static struct shash_alg alg = {
.init = sha1_base_init,
.update = sha1_ce_update,
.final = sha1_ce_final,
.finup = sha1_ce_finup,
.import = sha1_ce_import,
.export = sha1_ce_export,
.descsize = sizeof(struct sha1_ce_state),
.statesize = sizeof(struct sha1_state),
.digestsize = SHA1_DIGEST_SIZE,
.base = {
.cra_name = "sha1",
.cra_driver_name = "sha1-ce",
.cra_priority = 200,
.cra_blocksize = SHA1_BLOCK_SIZE,
.cra_module = THIS_MODULE,
}
};
static int __init sha1_ce_mod_init(void)
{
return crypto_register_shash(&alg);
}
static void __exit sha1_ce_mod_fini(void)
{
crypto_unregister_shash(&alg);
}
module_cpu_feature_match(SHA1, sha1_ce_mod_init);
module_exit(sha1_ce_mod_fini);