https://github.com/torvalds/linux
Tip revision: bc0195aad0daa2ad5b0d76cce22b167bc3435590 authored by Linus Torvalds on 12 July 2015, 22:10:30 UTC
Linux 4.2-rc2
Linux 4.2-rc2
Tip revision: bc0195a
sha1_ssse3_glue.c
/*
* Cryptographic API.
*
* Glue code for the SHA1 Secure Hash Algorithm assembler implementation using
* Supplemental SSE3 instructions.
*
* This file is based on sha1_generic.c
*
* Copyright (c) Alan Smithee.
* Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
* Copyright (c) Jean-Francois Dive <jef@linuxbe.org>
* Copyright (c) Mathias Krause <minipli@googlemail.com>
* Copyright (c) Chandramouli Narayanan <mouli@linux.intel.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <crypto/internal/hash.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/cryptohash.h>
#include <linux/types.h>
#include <crypto/sha.h>
#include <crypto/sha1_base.h>
#include <asm/fpu/api.h>
asmlinkage void sha1_transform_ssse3(u32 *digest, const char *data,
unsigned int rounds);
#ifdef CONFIG_AS_AVX
asmlinkage void sha1_transform_avx(u32 *digest, const char *data,
unsigned int rounds);
#endif
#ifdef CONFIG_AS_AVX2
#define SHA1_AVX2_BLOCK_OPTSIZE 4 /* optimal 4*64 bytes of SHA1 blocks */
asmlinkage void sha1_transform_avx2(u32 *digest, const char *data,
unsigned int rounds);
#endif
static void (*sha1_transform_asm)(u32 *, const char *, unsigned int);
static int sha1_ssse3_update(struct shash_desc *desc, const u8 *data,
unsigned int len)
{
struct sha1_state *sctx = shash_desc_ctx(desc);
if (!irq_fpu_usable() ||
(sctx->count % SHA1_BLOCK_SIZE) + len < SHA1_BLOCK_SIZE)
return crypto_sha1_update(desc, data, len);
/* make sure casting to sha1_block_fn() is safe */
BUILD_BUG_ON(offsetof(struct sha1_state, state) != 0);
kernel_fpu_begin();
sha1_base_do_update(desc, data, len,
(sha1_block_fn *)sha1_transform_asm);
kernel_fpu_end();
return 0;
}
static int sha1_ssse3_finup(struct shash_desc *desc, const u8 *data,
unsigned int len, u8 *out)
{
if (!irq_fpu_usable())
return crypto_sha1_finup(desc, data, len, out);
kernel_fpu_begin();
if (len)
sha1_base_do_update(desc, data, len,
(sha1_block_fn *)sha1_transform_asm);
sha1_base_do_finalize(desc, (sha1_block_fn *)sha1_transform_asm);
kernel_fpu_end();
return sha1_base_finish(desc, out);
}
/* Add padding and return the message digest. */
static int sha1_ssse3_final(struct shash_desc *desc, u8 *out)
{
return sha1_ssse3_finup(desc, NULL, 0, out);
}
#ifdef CONFIG_AS_AVX2
static void sha1_apply_transform_avx2(u32 *digest, const char *data,
unsigned int rounds)
{
/* Select the optimal transform based on data block size */
if (rounds >= SHA1_AVX2_BLOCK_OPTSIZE)
sha1_transform_avx2(digest, data, rounds);
else
sha1_transform_avx(digest, data, rounds);
}
#endif
static struct shash_alg alg = {
.digestsize = SHA1_DIGEST_SIZE,
.init = sha1_base_init,
.update = sha1_ssse3_update,
.final = sha1_ssse3_final,
.finup = sha1_ssse3_finup,
.descsize = sizeof(struct sha1_state),
.base = {
.cra_name = "sha1",
.cra_driver_name= "sha1-ssse3",
.cra_priority = 150,
.cra_flags = CRYPTO_ALG_TYPE_SHASH,
.cra_blocksize = SHA1_BLOCK_SIZE,
.cra_module = THIS_MODULE,
}
};
#ifdef CONFIG_AS_AVX
static bool __init avx_usable(void)
{
if (!cpu_has_xfeatures(XSTATE_SSE | XSTATE_YMM, NULL)) {
if (cpu_has_avx)
pr_info("AVX detected but unusable.\n");
return false;
}
return true;
}
#ifdef CONFIG_AS_AVX2
static bool __init avx2_usable(void)
{
if (avx_usable() && cpu_has_avx2 && boot_cpu_has(X86_FEATURE_BMI1) &&
boot_cpu_has(X86_FEATURE_BMI2))
return true;
return false;
}
#endif
#endif
static int __init sha1_ssse3_mod_init(void)
{
char *algo_name;
/* test for SSSE3 first */
if (cpu_has_ssse3) {
sha1_transform_asm = sha1_transform_ssse3;
algo_name = "SSSE3";
}
#ifdef CONFIG_AS_AVX
/* allow AVX to override SSSE3, it's a little faster */
if (avx_usable()) {
sha1_transform_asm = sha1_transform_avx;
algo_name = "AVX";
#ifdef CONFIG_AS_AVX2
/* allow AVX2 to override AVX, it's a little faster */
if (avx2_usable()) {
sha1_transform_asm = sha1_apply_transform_avx2;
algo_name = "AVX2";
}
#endif
}
#endif
if (sha1_transform_asm) {
pr_info("Using %s optimized SHA-1 implementation\n", algo_name);
return crypto_register_shash(&alg);
}
pr_info("Neither AVX nor AVX2 nor SSSE3 is available/usable.\n");
return -ENODEV;
}
static void __exit sha1_ssse3_mod_fini(void)
{
crypto_unregister_shash(&alg);
}
module_init(sha1_ssse3_mod_init);
module_exit(sha1_ssse3_mod_fini);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm, Supplemental SSE3 accelerated");
MODULE_ALIAS_CRYPTO("sha1");