| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Accelerated GHASH implementation with Intel PCLMULQDQ-NI |
| * instructions. This file contains glue code. |
| * |
| * Copyright (c) 2009 Intel Corp. |
| * Author: Huang Ying <ying.huang@intel.com> |
| */ |
| |
| #include <linux/err.h> |
| #include <linux/module.h> |
| #include <linux/init.h> |
| #include <linux/kernel.h> |
| #include <linux/crypto.h> |
| #include <crypto/algapi.h> |
| #include <crypto/cryptd.h> |
| #include <crypto/gf128mul.h> |
| #include <crypto/internal/hash.h> |
| #include <crypto/internal/simd.h> |
| #include <asm/cpu_device_id.h> |
| #include <asm/simd.h> |
| #include <asm/unaligned.h> |
| |
| #define GHASH_BLOCK_SIZE 16 |
| #define GHASH_DIGEST_SIZE 16 |
| |
| void clmul_ghash_mul(char *dst, const u128 *shash); |
| |
| void clmul_ghash_update(char *dst, const char *src, unsigned int srclen, |
| const u128 *shash); |
| |
| struct ghash_async_ctx { |
| struct cryptd_ahash *cryptd_tfm; |
| }; |
| |
| struct ghash_ctx { |
| u128 shash; |
| }; |
| |
| struct ghash_desc_ctx { |
| u8 buffer[GHASH_BLOCK_SIZE]; |
| u32 bytes; |
| }; |
| |
| static int ghash_init(struct shash_desc *desc) |
| { |
| struct ghash_desc_ctx *dctx = shash_desc_ctx(desc); |
| |
| memset(dctx, 0, sizeof(*dctx)); |
| |
| return 0; |
| } |
| |
| static int ghash_setkey(struct crypto_shash *tfm, |
| const u8 *key, unsigned int keylen) |
| { |
| struct ghash_ctx *ctx = crypto_shash_ctx(tfm); |
| u64 a, b; |
| |
| if (keylen != GHASH_BLOCK_SIZE) |
| return -EINVAL; |
| |
| /* perform multiplication by 'x' in GF(2^128) */ |
| a = get_unaligned_be64(key); |
| b = get_unaligned_be64(key + 8); |
| |
| ctx->shash.a = (b << 1) | (a >> 63); |
| ctx->shash.b = (a << 1) | (b >> 63); |
| |
| if (a >> 63) |
| ctx->shash.b ^= ((u64)0xc2) << 56; |
| |
| return 0; |
| } |
| |
| static int ghash_update(struct shash_desc *desc, |
| const u8 *src, unsigned int srclen) |
| { |
| struct ghash_desc_ctx *dctx = shash_desc_ctx(desc); |
| struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm); |
| u8 *dst = dctx->buffer; |
| |
| kernel_fpu_begin(); |
| if (dctx->bytes) { |
| int n = min(srclen, dctx->bytes); |
| u8 *pos = dst + (GHASH_BLOCK_SIZE - dctx->bytes); |
| |
| dctx->bytes -= n; |
| srclen -= n; |
| |
| while (n--) |
| *pos++ ^= *src++; |
| |
| if (!dctx->bytes) |
| clmul_ghash_mul(dst, &ctx->shash); |
| } |
| |
| clmul_ghash_update(dst, src, srclen, &ctx->shash); |
| kernel_fpu_end(); |
| |
| if (srclen & 0xf) { |
| src += srclen - (srclen & 0xf); |
| srclen &= 0xf; |
| dctx->bytes = GHASH_BLOCK_SIZE - srclen; |
| while (srclen--) |
| *dst++ ^= *src++; |
| } |
| |
| return 0; |
| } |
| |
| static void ghash_flush(struct ghash_ctx *ctx, struct ghash_desc_ctx *dctx) |
| { |
| u8 *dst = dctx->buffer; |
| |
| if (dctx->bytes) { |
| u8 *tmp = dst + (GHASH_BLOCK_SIZE - dctx->bytes); |
| |
| while (dctx->bytes--) |
| *tmp++ ^= 0; |
| |
| kernel_fpu_begin(); |
| clmul_ghash_mul(dst, &ctx->shash); |
| kernel_fpu_end(); |
| } |
| |
| dctx->bytes = 0; |
| } |
| |
| static int ghash_final(struct shash_desc *desc, u8 *dst) |
| { |
| struct ghash_desc_ctx *dctx = shash_desc_ctx(desc); |
| struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm); |
| u8 *buf = dctx->buffer; |
| |
| ghash_flush(ctx, dctx); |
| memcpy(dst, buf, GHASH_BLOCK_SIZE); |
| |
| return 0; |
| } |
| |
| static struct shash_alg ghash_alg = { |
| .digestsize = GHASH_DIGEST_SIZE, |
| .init = ghash_init, |
| .update = ghash_update, |
| .final = ghash_final, |
| .setkey = ghash_setkey, |
| .descsize = sizeof(struct ghash_desc_ctx), |
| .base = { |
| .cra_name = "__ghash", |
| .cra_driver_name = "__ghash-pclmulqdqni", |
| .cra_priority = 0, |
| .cra_flags = CRYPTO_ALG_INTERNAL, |
| .cra_blocksize = GHASH_BLOCK_SIZE, |
| .cra_ctxsize = sizeof(struct ghash_ctx), |
| .cra_module = THIS_MODULE, |
| }, |
| }; |
| |
| static int ghash_async_init(struct ahash_request *req) |
| { |
| struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); |
| struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm); |
| struct ahash_request *cryptd_req = ahash_request_ctx(req); |
| struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm; |
| struct shash_desc *desc = cryptd_shash_desc(cryptd_req); |
| struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm); |
| |
| desc->tfm = child; |
| return crypto_shash_init(desc); |
| } |
| |
| static int ghash_async_update(struct ahash_request *req) |
| { |
| struct ahash_request *cryptd_req = ahash_request_ctx(req); |
| struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); |
| struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm); |
| struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm; |
| |
| if (!crypto_simd_usable() || |
| (in_atomic() && cryptd_ahash_queued(cryptd_tfm))) { |
| memcpy(cryptd_req, req, sizeof(*req)); |
| ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base); |
| return crypto_ahash_update(cryptd_req); |
| } else { |
| struct shash_desc *desc = cryptd_shash_desc(cryptd_req); |
| return shash_ahash_update(req, desc); |
| } |
| } |
| |
| static int ghash_async_final(struct ahash_request *req) |
| { |
| struct ahash_request *cryptd_req = ahash_request_ctx(req); |
| struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); |
| struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm); |
| struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm; |
| |
| if (!crypto_simd_usable() || |
| (in_atomic() && cryptd_ahash_queued(cryptd_tfm))) { |
| memcpy(cryptd_req, req, sizeof(*req)); |
| ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base); |
| return crypto_ahash_final(cryptd_req); |
| } else { |
| struct shash_desc *desc = cryptd_shash_desc(cryptd_req); |
| return crypto_shash_final(desc, req->result); |
| } |
| } |
| |
| static int ghash_async_import(struct ahash_request *req, const void *in) |
| { |
| struct ahash_request *cryptd_req = ahash_request_ctx(req); |
| struct shash_desc *desc = cryptd_shash_desc(cryptd_req); |
| struct ghash_desc_ctx *dctx = shash_desc_ctx(desc); |
| |
| ghash_async_init(req); |
| memcpy(dctx, in, sizeof(*dctx)); |
| return 0; |
| |
| } |
| |
| static int ghash_async_export(struct ahash_request *req, void *out) |
| { |
| struct ahash_request *cryptd_req = ahash_request_ctx(req); |
| struct shash_desc *desc = cryptd_shash_desc(cryptd_req); |
| struct ghash_desc_ctx *dctx = shash_desc_ctx(desc); |
| |
| memcpy(out, dctx, sizeof(*dctx)); |
| return 0; |
| |
| } |
| |
| static int ghash_async_digest(struct ahash_request *req) |
| { |
| struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); |
| struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm); |
| struct ahash_request *cryptd_req = ahash_request_ctx(req); |
| struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm; |
| |
| if (!crypto_simd_usable() || |
| (in_atomic() && cryptd_ahash_queued(cryptd_tfm))) { |
| memcpy(cryptd_req, req, sizeof(*req)); |
| ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base); |
| return crypto_ahash_digest(cryptd_req); |
| } else { |
| struct shash_desc *desc = cryptd_shash_desc(cryptd_req); |
| struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm); |
| |
| desc->tfm = child; |
| return shash_ahash_digest(req, desc); |
| } |
| } |
| |
| static int ghash_async_setkey(struct crypto_ahash *tfm, const u8 *key, |
| unsigned int keylen) |
| { |
| struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm); |
| struct crypto_ahash *child = &ctx->cryptd_tfm->base; |
| |
| crypto_ahash_clear_flags(child, CRYPTO_TFM_REQ_MASK); |
| crypto_ahash_set_flags(child, crypto_ahash_get_flags(tfm) |
| & CRYPTO_TFM_REQ_MASK); |
| return crypto_ahash_setkey(child, key, keylen); |
| } |
| |
| static int ghash_async_init_tfm(struct crypto_tfm *tfm) |
| { |
| struct cryptd_ahash *cryptd_tfm; |
| struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm); |
| |
| cryptd_tfm = cryptd_alloc_ahash("__ghash-pclmulqdqni", |
| CRYPTO_ALG_INTERNAL, |
| CRYPTO_ALG_INTERNAL); |
| if (IS_ERR(cryptd_tfm)) |
| return PTR_ERR(cryptd_tfm); |
| ctx->cryptd_tfm = cryptd_tfm; |
| crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm), |
| sizeof(struct ahash_request) + |
| crypto_ahash_reqsize(&cryptd_tfm->base)); |
| |
| return 0; |
| } |
| |
| static void ghash_async_exit_tfm(struct crypto_tfm *tfm) |
| { |
| struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm); |
| |
| cryptd_free_ahash(ctx->cryptd_tfm); |
| } |
| |
| static struct ahash_alg ghash_async_alg = { |
| .init = ghash_async_init, |
| .update = ghash_async_update, |
| .final = ghash_async_final, |
| .setkey = ghash_async_setkey, |
| .digest = ghash_async_digest, |
| .export = ghash_async_export, |
| .import = ghash_async_import, |
| .halg = { |
| .digestsize = GHASH_DIGEST_SIZE, |
| .statesize = sizeof(struct ghash_desc_ctx), |
| .base = { |
| .cra_name = "ghash", |
| .cra_driver_name = "ghash-clmulni", |
| .cra_priority = 400, |
| .cra_ctxsize = sizeof(struct ghash_async_ctx), |
| .cra_flags = CRYPTO_ALG_ASYNC, |
| .cra_blocksize = GHASH_BLOCK_SIZE, |
| .cra_module = THIS_MODULE, |
| .cra_init = ghash_async_init_tfm, |
| .cra_exit = ghash_async_exit_tfm, |
| }, |
| }, |
| }; |
| |
| static const struct x86_cpu_id pcmul_cpu_id[] = { |
| X86_MATCH_FEATURE(X86_FEATURE_PCLMULQDQ, NULL), /* Pickle-Mickle-Duck */ |
| {} |
| }; |
| MODULE_DEVICE_TABLE(x86cpu, pcmul_cpu_id); |
| |
| static int __init ghash_pclmulqdqni_mod_init(void) |
| { |
| int err; |
| |
| if (!x86_match_cpu(pcmul_cpu_id)) |
| return -ENODEV; |
| |
| err = crypto_register_shash(&ghash_alg); |
| if (err) |
| goto err_out; |
| err = crypto_register_ahash(&ghash_async_alg); |
| if (err) |
| goto err_shash; |
| |
| return 0; |
| |
| err_shash: |
| crypto_unregister_shash(&ghash_alg); |
| err_out: |
| return err; |
| } |
| |
| static void __exit ghash_pclmulqdqni_mod_exit(void) |
| { |
| crypto_unregister_ahash(&ghash_async_alg); |
| crypto_unregister_shash(&ghash_alg); |
| } |
| |
| module_init(ghash_pclmulqdqni_mod_init); |
| module_exit(ghash_pclmulqdqni_mod_exit); |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_DESCRIPTION("GHASH hash function, accelerated by PCLMULQDQ-NI"); |
| MODULE_ALIAS_CRYPTO("ghash"); |