| /* |
| * Poly1305 authenticator algorithm, RFC7539, SIMD glue code |
| * |
| * Copyright (C) 2015 Martin Willi |
| * |
| * 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. |
| */ |
| |
| #include <crypto/algapi.h> |
| #include <crypto/internal/hash.h> |
| #include <crypto/internal/poly1305.h> |
| #include <linux/crypto.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <asm/fpu/api.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 bool poly1305_use_avx2 __ro_after_init; |
| |
| 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_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) && |
| 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; |
| } |
| |
| static int poly1305_simd_update(struct shash_desc *desc, |
| const u8 *src, unsigned int srclen) |
| { |
| struct poly1305_desc_ctx *dctx = shash_desc_ctx(desc); |
| unsigned int bytes; |
| |
| /* kernel_fpu_begin/end is costly, use fallback for small updates */ |
| if (srclen <= 288 || !may_use_simd()) |
| return crypto_poly1305_update(desc, src, srclen); |
| |
| kernel_fpu_begin(); |
| |
| 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) { |
| poly1305_simd_blocks(dctx, dctx->buf, |
| POLY1305_BLOCK_SIZE); |
| dctx->buflen = 0; |
| } |
| } |
| |
| if (likely(srclen >= POLY1305_BLOCK_SIZE)) { |
| bytes = poly1305_simd_blocks(dctx, src, srclen); |
| src += srclen - bytes; |
| srclen = bytes; |
| } |
| |
| kernel_fpu_end(); |
| |
| if (unlikely(srclen)) { |
| dctx->buflen = srclen; |
| memcpy(dctx->buf, 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 -ENODEV; |
| |
| poly1305_use_avx2 = 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); |
| alg.descsize = sizeof(struct poly1305_desc_ctx) + 5 * sizeof(u32); |
| if (poly1305_use_avx2) |
| alg.descsize += 10 * sizeof(u32); |
| |
| return crypto_register_shash(&alg); |
| } |
| |
| static void __exit poly1305_simd_mod_exit(void) |
| { |
| 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"); |