diff options
author | Huang Ying <ying.huang@intel.com> | 2009-10-19 11:53:06 +0900 |
---|---|---|
committer | Herbert Xu <herbert@gondor.apana.org.au> | 2009-10-19 11:53:06 +0900 |
commit | 0e1227d356e9b2fe0500d6cc7084f752040a1e0e (patch) | |
tree | 6f059b8e3c31539942ad244e7aadabcb54e8d904 /arch/x86/crypto/ghash-clmulni-intel_glue.c | |
parent | 4c6ab3ee4cdb86cbd4e9400dd22fad7701cbe795 (diff) |
crypto: ghash - Add PCLMULQDQ accelerated implementation
PCLMULQDQ is used to accelerate the most time-consuming part of GHASH,
carry-less multiplication. More information about PCLMULQDQ can be
found at:
http://software.intel.com/en-us/articles/carry-less-multiplication-and-its-usage-for-computing-the-gcm-mode/
Because PCLMULQDQ changes XMM state, its usage must be enclosed with
kernel_fpu_begin/end, which can be used only in process context, the
acceleration is implemented as crypto_ahash. That is, request in soft
IRQ context will be defered to the cryptd kernel thread.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'arch/x86/crypto/ghash-clmulni-intel_glue.c')
-rw-r--r-- | arch/x86/crypto/ghash-clmulni-intel_glue.c | 333 |
1 files changed, 333 insertions, 0 deletions
diff --git a/arch/x86/crypto/ghash-clmulni-intel_glue.c b/arch/x86/crypto/ghash-clmulni-intel_glue.c new file mode 100644 index 00000000000..65d409644d7 --- /dev/null +++ b/arch/x86/crypto/ghash-clmulni-intel_glue.c @@ -0,0 +1,333 @@ +/* + * 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> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + */ + +#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 <asm/i387.h> + +#define GHASH_BLOCK_SIZE 16 +#define GHASH_DIGEST_SIZE 16 + +void clmul_ghash_mul(char *dst, const be128 *shash); + +void clmul_ghash_update(char *dst, const char *src, unsigned int srclen, + const be128 *shash); + +void clmul_ghash_setkey(be128 *shash, const u8 *key); + +struct ghash_async_ctx { + struct cryptd_ahash *cryptd_tfm; +}; + +struct ghash_ctx { + be128 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); + + if (keylen != GHASH_BLOCK_SIZE) { + crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); + return -EINVAL; + } + + clmul_ghash_setkey(&ctx->shash, key); + + 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_TYPE_SHASH, + .cra_blocksize = GHASH_BLOCK_SIZE, + .cra_ctxsize = sizeof(struct ghash_ctx), + .cra_module = THIS_MODULE, + .cra_list = LIST_HEAD_INIT(ghash_alg.base.cra_list), + }, +}; + +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; + + if (irq_fpu_usable()) { + memcpy(cryptd_req, req, sizeof(*req)); + ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base); + return crypto_ahash_init(cryptd_req); + } else { + struct shash_desc *desc = cryptd_shash_desc(cryptd_req); + struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm); + + desc->tfm = child; + desc->flags = req->base.flags; + return crypto_shash_init(desc); + } +} + +static int ghash_async_update(struct ahash_request *req) +{ + struct ahash_request *cryptd_req = ahash_request_ctx(req); + + if (irq_fpu_usable()) { + 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; + + 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); + + if (irq_fpu_usable()) { + 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; + + 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_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 (irq_fpu_usable()) { + 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; + desc->flags = req->base.flags; + 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; + int err; + + crypto_ahash_clear_flags(child, CRYPTO_TFM_REQ_MASK); + crypto_ahash_set_flags(child, crypto_ahash_get_flags(tfm) + & CRYPTO_TFM_REQ_MASK); + err = crypto_ahash_setkey(child, key, keylen); + crypto_ahash_set_flags(tfm, crypto_ahash_get_flags(child) + & CRYPTO_TFM_RES_MASK); + + return 0; +} + +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", 0, 0); + 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, + .halg = { + .digestsize = GHASH_DIGEST_SIZE, + .base = { + .cra_name = "ghash", + .cra_driver_name = "ghash-clmulni", + .cra_priority = 400, + .cra_flags = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC, + .cra_blocksize = GHASH_BLOCK_SIZE, + .cra_type = &crypto_ahash_type, + .cra_module = THIS_MODULE, + .cra_list = LIST_HEAD_INIT(ghash_async_alg.halg.base.cra_list), + .cra_init = ghash_async_init_tfm, + .cra_exit = ghash_async_exit_tfm, + }, + }, +}; + +static int __init ghash_pclmulqdqni_mod_init(void) +{ + int err; + + if (!cpu_has_pclmulqdq) { + printk(KERN_INFO "Intel PCLMULQDQ-NI instructions are not" + " detected.\n"); + 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 Message Digest Algorithm, " + "acclerated by PCLMULQDQ-NI"); +MODULE_ALIAS("ghash"); |