linux/arch/x86/crypto/poly1305_glue.c

244 lines
6.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Poly1305 authenticator algorithm, RFC7539, SIMD glue code
*
* Copyright (C) 2015 Martin Willi
*/
#include <crypto/algapi.h>
#include <crypto/internal/hash.h>
#include <crypto/internal/poly1305.h>
#include <crypto/internal/simd.h>
#include <linux/crypto.h>
#include <linux/jump_label.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <asm/simd.h>
asmlinkage void poly1305_block_sse2(u32 *h, const u8 *src,
const u32 *r, unsigned int blocks);
asmlinkage void poly1305_2block_sse2(u32 *h, const u8 *src, const u32 *r,
unsigned int blocks, const u32 *u);
asmlinkage void poly1305_4block_avx2(u32 *h, const u8 *src, const u32 *r,
unsigned int blocks, const u32 *u);
static __ro_after_init DEFINE_STATIC_KEY_FALSE(poly1305_use_simd);
static __ro_after_init DEFINE_STATIC_KEY_FALSE(poly1305_use_avx2);
static void poly1305_simd_mult(u32 *a, const u32 *b)
{
u8 m[POLY1305_BLOCK_SIZE];
memset(m, 0, sizeof(m));
/* The poly1305 block function adds a hi-bit to the accumulator which
* we don't need for key multiplication; compensate for it. */
a[4] -= 1 << 24;
poly1305_block_sse2(a, m, b, 1);
}
static unsigned int poly1305_scalar_blocks(struct poly1305_desc_ctx *dctx,
const u8 *src, unsigned int srclen)
{
unsigned int datalen;
if (unlikely(!dctx->sset)) {
datalen = crypto_poly1305_setdesckey(dctx, src, srclen);
src += srclen - datalen;
srclen = datalen;
}
if (srclen >= POLY1305_BLOCK_SIZE) {
poly1305_core_blocks(&dctx->h, dctx->r, src,
srclen / POLY1305_BLOCK_SIZE, 1);
srclen %= POLY1305_BLOCK_SIZE;
}
return srclen;
}
static unsigned int poly1305_simd_blocks(struct poly1305_desc_ctx *dctx,
const u8 *src, unsigned int srclen)
{
unsigned int blocks, datalen;
if (unlikely(!dctx->sset)) {
datalen = crypto_poly1305_setdesckey(dctx, src, srclen);
src += srclen - datalen;
srclen = datalen;
}
if (IS_ENABLED(CONFIG_AS_AVX2) &&
static_branch_likely(&poly1305_use_avx2) &&
srclen >= POLY1305_BLOCK_SIZE * 4) {
if (unlikely(dctx->rset < 4)) {
if (dctx->rset < 2) {
dctx->r[1] = dctx->r[0];
poly1305_simd_mult(dctx->r[1].r, dctx->r[0].r);
}
dctx->r[2] = dctx->r[1];
poly1305_simd_mult(dctx->r[2].r, dctx->r[0].r);
dctx->r[3] = dctx->r[2];
poly1305_simd_mult(dctx->r[3].r, dctx->r[0].r);
dctx->rset = 4;
}
blocks = srclen / (POLY1305_BLOCK_SIZE * 4);
poly1305_4block_avx2(dctx->h.h, src, dctx->r[0].r, blocks,
dctx->r[1].r);
src += POLY1305_BLOCK_SIZE * 4 * blocks;
srclen -= POLY1305_BLOCK_SIZE * 4 * blocks;
}
if (likely(srclen >= POLY1305_BLOCK_SIZE * 2)) {
if (unlikely(dctx->rset < 2)) {
dctx->r[1] = dctx->r[0];
poly1305_simd_mult(dctx->r[1].r, dctx->r[0].r);
dctx->rset = 2;
}
blocks = srclen / (POLY1305_BLOCK_SIZE * 2);
poly1305_2block_sse2(dctx->h.h, src, dctx->r[0].r,
blocks, dctx->r[1].r);
src += POLY1305_BLOCK_SIZE * 2 * blocks;
srclen -= POLY1305_BLOCK_SIZE * 2 * blocks;
}
if (srclen >= POLY1305_BLOCK_SIZE) {
poly1305_block_sse2(dctx->h.h, src, dctx->r[0].r, 1);
srclen -= POLY1305_BLOCK_SIZE;
}
return srclen;
}
void poly1305_init_arch(struct poly1305_desc_ctx *desc, const u8 *key)
{
poly1305_init_generic(desc, key);
}
EXPORT_SYMBOL(poly1305_init_arch);
void poly1305_update_arch(struct poly1305_desc_ctx *dctx, const u8 *src,
unsigned int srclen)
{
unsigned int bytes;
if (unlikely(dctx->buflen)) {
bytes = min(srclen, POLY1305_BLOCK_SIZE - dctx->buflen);
memcpy(dctx->buf + dctx->buflen, src, bytes);
src += bytes;
srclen -= bytes;
dctx->buflen += bytes;
if (dctx->buflen == POLY1305_BLOCK_SIZE) {
if (static_branch_likely(&poly1305_use_simd) &&
likely(crypto_simd_usable())) {
kernel_fpu_begin();
poly1305_simd_blocks(dctx, dctx->buf,
POLY1305_BLOCK_SIZE);
kernel_fpu_end();
} else {
poly1305_scalar_blocks(dctx, dctx->buf,
POLY1305_BLOCK_SIZE);
}
dctx->buflen = 0;
}
}
if (likely(srclen >= POLY1305_BLOCK_SIZE)) {
if (static_branch_likely(&poly1305_use_simd) &&
likely(crypto_simd_usable())) {
kernel_fpu_begin();
bytes = poly1305_simd_blocks(dctx, src, srclen);
kernel_fpu_end();
} else {
bytes = poly1305_scalar_blocks(dctx, src, srclen);
}
src += srclen - bytes;
srclen = bytes;
}
if (unlikely(srclen)) {
dctx->buflen = srclen;
memcpy(dctx->buf, src, srclen);
}
}
EXPORT_SYMBOL(poly1305_update_arch);
void poly1305_final_arch(struct poly1305_desc_ctx *desc, u8 *digest)
{
poly1305_final_generic(desc, digest);
}
EXPORT_SYMBOL(poly1305_final_arch);
static int crypto_poly1305_init(struct shash_desc *desc)
{
struct poly1305_desc_ctx *dctx = shash_desc_ctx(desc);
poly1305_core_init(&dctx->h);
dctx->buflen = 0;
dctx->rset = 0;
dctx->sset = false;
return 0;
}
static int crypto_poly1305_final(struct shash_desc *desc, u8 *dst)
{
struct poly1305_desc_ctx *dctx = shash_desc_ctx(desc);
if (unlikely(!dctx->sset))
return -ENOKEY;
poly1305_final_generic(dctx, dst);
return 0;
}
static int poly1305_simd_update(struct shash_desc *desc,
const u8 *src, unsigned int srclen)
{
struct poly1305_desc_ctx *dctx = shash_desc_ctx(desc);
poly1305_update_arch(dctx, src, srclen);
return 0;
}
static struct shash_alg alg = {
.digestsize = POLY1305_DIGEST_SIZE,
.init = crypto_poly1305_init,
.update = poly1305_simd_update,
.final = crypto_poly1305_final,
.descsize = sizeof(struct poly1305_desc_ctx),
.base = {
.cra_name = "poly1305",
.cra_driver_name = "poly1305-simd",
.cra_priority = 300,
.cra_blocksize = POLY1305_BLOCK_SIZE,
.cra_module = THIS_MODULE,
},
};
static int __init poly1305_simd_mod_init(void)
{
if (!boot_cpu_has(X86_FEATURE_XMM2))
return 0;
static_branch_enable(&poly1305_use_simd);
if (IS_ENABLED(CONFIG_AS_AVX2) &&
boot_cpu_has(X86_FEATURE_AVX) &&
boot_cpu_has(X86_FEATURE_AVX2) &&
cpu_has_xfeatures(XFEATURE_MASK_SSE | XFEATURE_MASK_YMM, NULL))
static_branch_enable(&poly1305_use_avx2);
return IS_REACHABLE(CONFIG_CRYPTO_HASH) ? crypto_register_shash(&alg) : 0;
}
static void __exit poly1305_simd_mod_exit(void)
{
if (IS_REACHABLE(CONFIG_CRYPTO_HASH))
crypto_unregister_shash(&alg);
}
module_init(poly1305_simd_mod_init);
module_exit(poly1305_simd_mod_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Martin Willi <martin@strongswan.org>");
MODULE_DESCRIPTION("Poly1305 authenticator");
MODULE_ALIAS_CRYPTO("poly1305");
MODULE_ALIAS_CRYPTO("poly1305-simd");