diff options
Diffstat (limited to 'arch/x86/crypto/polyval-clmulni_glue.c')
| -rw-r--r-- | arch/x86/crypto/polyval-clmulni_glue.c | 203 |
1 files changed, 203 insertions, 0 deletions
diff --git a/arch/x86/crypto/polyval-clmulni_glue.c b/arch/x86/crypto/polyval-clmulni_glue.c new file mode 100644 index 000000000000..b7664d018851 --- /dev/null +++ b/arch/x86/crypto/polyval-clmulni_glue.c @@ -0,0 +1,203 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Glue code for POLYVAL using PCMULQDQ-NI + * + * Copyright (c) 2007 Nokia Siemens Networks - Mikko Herranen <mh1@iki.fi> + * Copyright (c) 2009 Intel Corp. + * Author: Huang Ying <ying.huang@intel.com> + * Copyright 2021 Google LLC + */ + +/* + * Glue code based on ghash-clmulni-intel_glue.c. + * + * This implementation of POLYVAL uses montgomery multiplication + * accelerated by PCLMULQDQ-NI to implement the finite field + * operations. + */ + +#include <crypto/algapi.h> +#include <crypto/internal/hash.h> +#include <crypto/internal/simd.h> +#include <crypto/polyval.h> +#include <linux/crypto.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <asm/cpu_device_id.h> +#include <asm/simd.h> + +#define NUM_KEY_POWERS 8 + +struct polyval_tfm_ctx { + /* + * These powers must be in the order h^8, ..., h^1. + */ + u8 key_powers[NUM_KEY_POWERS][POLYVAL_BLOCK_SIZE]; +}; + +struct polyval_desc_ctx { + u8 buffer[POLYVAL_BLOCK_SIZE]; + u32 bytes; +}; + +asmlinkage void clmul_polyval_update(const struct polyval_tfm_ctx *keys, + const u8 *in, size_t nblocks, u8 *accumulator); +asmlinkage void clmul_polyval_mul(u8 *op1, const u8 *op2); + +static void internal_polyval_update(const struct polyval_tfm_ctx *keys, + const u8 *in, size_t nblocks, u8 *accumulator) +{ + if (likely(crypto_simd_usable())) { + kernel_fpu_begin(); + clmul_polyval_update(keys, in, nblocks, accumulator); + kernel_fpu_end(); + } else { + polyval_update_non4k(keys->key_powers[NUM_KEY_POWERS-1], in, + nblocks, accumulator); + } +} + +static void internal_polyval_mul(u8 *op1, const u8 *op2) +{ + if (likely(crypto_simd_usable())) { + kernel_fpu_begin(); + clmul_polyval_mul(op1, op2); + kernel_fpu_end(); + } else { + polyval_mul_non4k(op1, op2); + } +} + +static int polyval_x86_setkey(struct crypto_shash *tfm, + const u8 *key, unsigned int keylen) +{ + struct polyval_tfm_ctx *tctx = crypto_shash_ctx(tfm); + int i; + + if (keylen != POLYVAL_BLOCK_SIZE) + return -EINVAL; + + memcpy(tctx->key_powers[NUM_KEY_POWERS-1], key, POLYVAL_BLOCK_SIZE); + + for (i = NUM_KEY_POWERS-2; i >= 0; i--) { + memcpy(tctx->key_powers[i], key, POLYVAL_BLOCK_SIZE); + internal_polyval_mul(tctx->key_powers[i], + tctx->key_powers[i+1]); + } + + return 0; +} + +static int polyval_x86_init(struct shash_desc *desc) +{ + struct polyval_desc_ctx *dctx = shash_desc_ctx(desc); + + memset(dctx, 0, sizeof(*dctx)); + + return 0; +} + +static int polyval_x86_update(struct shash_desc *desc, + const u8 *src, unsigned int srclen) +{ + struct polyval_desc_ctx *dctx = shash_desc_ctx(desc); + const struct polyval_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm); + u8 *pos; + unsigned int nblocks; + unsigned int n; + + if (dctx->bytes) { + n = min(srclen, dctx->bytes); + pos = dctx->buffer + POLYVAL_BLOCK_SIZE - dctx->bytes; + + dctx->bytes -= n; + srclen -= n; + + while (n--) + *pos++ ^= *src++; + + if (!dctx->bytes) + internal_polyval_mul(dctx->buffer, + tctx->key_powers[NUM_KEY_POWERS-1]); + } + + while (srclen >= POLYVAL_BLOCK_SIZE) { + /* Allow rescheduling every 4K bytes. */ + nblocks = min(srclen, 4096U) / POLYVAL_BLOCK_SIZE; + internal_polyval_update(tctx, src, nblocks, dctx->buffer); + srclen -= nblocks * POLYVAL_BLOCK_SIZE; + src += nblocks * POLYVAL_BLOCK_SIZE; + } + + if (srclen) { + dctx->bytes = POLYVAL_BLOCK_SIZE - srclen; + pos = dctx->buffer; + while (srclen--) + *pos++ ^= *src++; + } + + return 0; +} + +static int polyval_x86_final(struct shash_desc *desc, u8 *dst) +{ + struct polyval_desc_ctx *dctx = shash_desc_ctx(desc); + const struct polyval_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm); + + if (dctx->bytes) { + internal_polyval_mul(dctx->buffer, + tctx->key_powers[NUM_KEY_POWERS-1]); + } + + memcpy(dst, dctx->buffer, POLYVAL_BLOCK_SIZE); + + return 0; +} + +static struct shash_alg polyval_alg = { + .digestsize = POLYVAL_DIGEST_SIZE, + .init = polyval_x86_init, + .update = polyval_x86_update, + .final = polyval_x86_final, + .setkey = polyval_x86_setkey, + .descsize = sizeof(struct polyval_desc_ctx), + .base = { + .cra_name = "polyval", + .cra_driver_name = "polyval-clmulni", + .cra_priority = 200, + .cra_blocksize = POLYVAL_BLOCK_SIZE, + .cra_ctxsize = sizeof(struct polyval_tfm_ctx), + .cra_module = THIS_MODULE, + }, +}; + +__maybe_unused static const struct x86_cpu_id pcmul_cpu_id[] = { + X86_MATCH_FEATURE(X86_FEATURE_PCLMULQDQ, NULL), + {} +}; +MODULE_DEVICE_TABLE(x86cpu, pcmul_cpu_id); + +static int __init polyval_clmulni_mod_init(void) +{ + if (!x86_match_cpu(pcmul_cpu_id)) + return -ENODEV; + + if (!boot_cpu_has(X86_FEATURE_AVX)) + return -ENODEV; + + return crypto_register_shash(&polyval_alg); +} + +static void __exit polyval_clmulni_mod_exit(void) +{ + crypto_unregister_shash(&polyval_alg); +} + +module_init(polyval_clmulni_mod_init); +module_exit(polyval_clmulni_mod_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("POLYVAL hash function accelerated by PCLMULQDQ-NI"); +MODULE_ALIAS_CRYPTO("polyval"); +MODULE_ALIAS_CRYPTO("polyval-clmulni"); |