arch/x86/crypto/ghash-clmulni-intel_glue.c - maze/linux - Git at Google

 /*
  * 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/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 <asm/i387.h>
 #include <asm/cpu_device_id.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);

 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);
 	be128 *x = (be128 *)key;
 	u64 a, b;

 	if (keylen != GHASH_BLOCK_SIZE) {
 		crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
 		return -EINVAL;
 	}

 	/* perform multiplication by 'x' in GF(2^128) */
 	a = be64_to_cpu(x->a);
 	b = be64_to_cpu(x->b);

 	ctx->shash.a = (__be64)((b << 1) | (a >> 63));
 	ctx->shash.b = (__be64)((a << 1) | (b >> 63));

 	if (a >> 63)
 		ctx->shash.b ^= cpu_to_be64(0xc2);

 	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,
 	},
 };

 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 err;
 }

 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_init		= ghash_async_init_tfm,
 			.cra_exit		= ghash_async_exit_tfm,
 		},
 	},
 };

 static const struct x86_cpu_id pcmul_cpu_id[] = {
 	X86_FEATURE_MATCH(X86_FEATURE_PCLMULQDQ), /* 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 Message Digest Algorithm, "
 		   "acclerated by PCLMULQDQ-NI");
 MODULE_ALIAS("ghash");
	/*
	* 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/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 <asm/i387.h>
	#include <asm/cpu_device_id.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);

	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);
	be128 x = (be128 )key;
	u64 a, b;

	if (keylen != GHASH_BLOCK_SIZE) {
	crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
	return -EINVAL;
	}

	/* perform multiplication by 'x' in GF(2^128) */
	a = be64_to_cpu(x->a);
	b = be64_to_cpu(x->b);

	ctx->shash.a = (__be64)((b << 1) \| (a >> 63));
	ctx->shash.b = (__be64)((a << 1) \| (b >> 63));

	if (a >> 63)
	ctx->shash.b ^= cpu_to_be64(0xc2);

	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,
	},
	};

	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 err;
	}

	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_init = ghash_async_init_tfm,
	.cra_exit = ghash_async_exit_tfm,
	},
	},
	};

	static const struct x86_cpu_id pcmul_cpu_id[] = {
	X86_FEATURE_MATCH(X86_FEATURE_PCLMULQDQ), /* 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 Message Digest Algorithm, "
	"acclerated by PCLMULQDQ-NI");
	MODULE_ALIAS("ghash");