arch/x86/crypto/cast5_avx_glue.c - kernel/msm-4.9 - Gitiles

 /*
  * Glue Code for the AVX assembler implemention of the Cast5 Cipher
  *
  * Copyright (C) 2012 Johannes Goetzfried
  *     <Johannes.Goetzfried@informatik.stud.uni-erlangen.de>
  *
  * 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.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
  * USA
  *
  */

 #include <linux/module.h>
 #include <linux/hardirq.h>
 #include <linux/types.h>
 #include <linux/crypto.h>
 #include <linux/err.h>
 #include <crypto/ablk_helper.h>
 #include <crypto/algapi.h>
 #include <crypto/cast5.h>
 #include <crypto/cryptd.h>
 #include <crypto/ctr.h>
 #include <asm/xcr.h>
 #include <asm/xsave.h>
 #include <asm/crypto/glue_helper.h>

 #define CAST5_PARALLEL_BLOCKS 16

 asmlinkage void cast5_ecb_enc_16way(struct cast5_ctx *ctx, u8 *dst,
 				    const u8 *src);
 asmlinkage void cast5_ecb_dec_16way(struct cast5_ctx *ctx, u8 *dst,
 				    const u8 *src);
 asmlinkage void cast5_cbc_dec_16way(struct cast5_ctx *ctx, u8 *dst,
 				    const u8 *src);
 asmlinkage void cast5_ctr_16way(struct cast5_ctx *ctx, u8 *dst, const u8 *src,
 				__be64 *iv);

 static inline bool cast5_fpu_begin(bool fpu_enabled, unsigned int nbytes)
 {
 	return glue_fpu_begin(CAST5_BLOCK_SIZE, CAST5_PARALLEL_BLOCKS,
 			      NULL, fpu_enabled, nbytes);
 }

 static inline void cast5_fpu_end(bool fpu_enabled)
 {
 	return glue_fpu_end(fpu_enabled);
 }

 static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk,
 		     bool enc)
 {
 	bool fpu_enabled = false;
 	struct cast5_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 	const unsigned int bsize = CAST5_BLOCK_SIZE;
 	unsigned int nbytes;
 	void (*fn)(struct cast5_ctx *ctx, u8 *dst, const u8 *src);
 	int err;

 	fn = (enc) ? cast5_ecb_enc_16way : cast5_ecb_dec_16way;

 	err = blkcipher_walk_virt(desc, walk);
 	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;

 	while ((nbytes = walk->nbytes)) {
 		u8 *wsrc = walk->src.virt.addr;
 		u8 *wdst = walk->dst.virt.addr;

 		fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes);

 		/* Process multi-block batch */
 		if (nbytes >= bsize * CAST5_PARALLEL_BLOCKS) {
 			do {
 				fn(ctx, wdst, wsrc);

 				wsrc += bsize * CAST5_PARALLEL_BLOCKS;
 				wdst += bsize * CAST5_PARALLEL_BLOCKS;
 				nbytes -= bsize * CAST5_PARALLEL_BLOCKS;
 			} while (nbytes >= bsize * CAST5_PARALLEL_BLOCKS);

 			if (nbytes < bsize)
 				goto done;
 		}

 		fn = (enc) ? __cast5_encrypt : __cast5_decrypt;

 		/* Handle leftovers */
 		do {
 			fn(ctx, wdst, wsrc);

 			wsrc += bsize;
 			wdst += bsize;
 			nbytes -= bsize;
 		} while (nbytes >= bsize);

 done:
 		err = blkcipher_walk_done(desc, walk, nbytes);
 	}

 	cast5_fpu_end(fpu_enabled);
 	return err;
 }

 static int ecb_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 		       struct scatterlist *src, unsigned int nbytes)
 {
 	struct blkcipher_walk walk;

 	blkcipher_walk_init(&walk, dst, src, nbytes);
 	return ecb_crypt(desc, &walk, true);
 }

 static int ecb_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 		       struct scatterlist *src, unsigned int nbytes)
 {
 	struct blkcipher_walk walk;

 	blkcipher_walk_init(&walk, dst, src, nbytes);
 	return ecb_crypt(desc, &walk, false);
 }

 static unsigned int __cbc_encrypt(struct blkcipher_desc *desc,
 				  struct blkcipher_walk *walk)
 {
 	struct cast5_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 	const unsigned int bsize = CAST5_BLOCK_SIZE;
 	unsigned int nbytes = walk->nbytes;
 	u64 *src = (u64 *)walk->src.virt.addr;
 	u64 *dst = (u64 *)walk->dst.virt.addr;
 	u64 *iv = (u64 *)walk->iv;

 	do {
 		*dst = *src ^ *iv;
 		__cast5_encrypt(ctx, (u8 *)dst, (u8 *)dst);
 		iv = dst;

 		src += 1;
 		dst += 1;
 		nbytes -= bsize;
 	} while (nbytes >= bsize);

 	*(u64 *)walk->iv = *iv;
 	return nbytes;
 }

 static int cbc_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 		       struct scatterlist *src, unsigned int nbytes)
 {
 	struct blkcipher_walk walk;
 	int err;

 	blkcipher_walk_init(&walk, dst, src, nbytes);
 	err = blkcipher_walk_virt(desc, &walk);

 	while ((nbytes = walk.nbytes)) {
 		nbytes = __cbc_encrypt(desc, &walk);
 		err = blkcipher_walk_done(desc, &walk, nbytes);
 	}

 	return err;
 }

 static unsigned int __cbc_decrypt(struct blkcipher_desc *desc,
 				  struct blkcipher_walk *walk)
 {
 	struct cast5_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 	const unsigned int bsize = CAST5_BLOCK_SIZE;
 	unsigned int nbytes = walk->nbytes;
 	u64 *src = (u64 *)walk->src.virt.addr;
 	u64 *dst = (u64 *)walk->dst.virt.addr;
 	u64 last_iv;

 	/* Start of the last block. */
 	src += nbytes / bsize - 1;
 	dst += nbytes / bsize - 1;

 	last_iv = *src;

 	/* Process multi-block batch */
 	if (nbytes >= bsize * CAST5_PARALLEL_BLOCKS) {
 		do {
 			nbytes -= bsize * (CAST5_PARALLEL_BLOCKS - 1);
 			src -= CAST5_PARALLEL_BLOCKS - 1;
 			dst -= CAST5_PARALLEL_BLOCKS - 1;

 			cast5_cbc_dec_16way(ctx, (u8 *)dst, (u8 *)src);

 			nbytes -= bsize;
 			if (nbytes < bsize)
 				goto done;

 			*dst ^= *(src - 1);
 			src -= 1;
 			dst -= 1;
 		} while (nbytes >= bsize * CAST5_PARALLEL_BLOCKS);
 	}

 	/* Handle leftovers */
 	for (;;) {
 		__cast5_decrypt(ctx, (u8 *)dst, (u8 *)src);

 		nbytes -= bsize;
 		if (nbytes < bsize)
 			break;

 		*dst ^= *(src - 1);
 		src -= 1;
 		dst -= 1;
 	}

 done:
 	*dst ^= *(u64 *)walk->iv;
 	*(u64 *)walk->iv = last_iv;

 	return nbytes;
 }

 static int cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 		       struct scatterlist *src, unsigned int nbytes)
 {
 	bool fpu_enabled = false;
 	struct blkcipher_walk walk;
 	int err;

 	blkcipher_walk_init(&walk, dst, src, nbytes);
 	err = blkcipher_walk_virt(desc, &walk);
 	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;

 	while ((nbytes = walk.nbytes)) {
 		fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes);
 		nbytes = __cbc_decrypt(desc, &walk);
 		err = blkcipher_walk_done(desc, &walk, nbytes);
 	}

 	cast5_fpu_end(fpu_enabled);
 	return err;
 }

 static void ctr_crypt_final(struct blkcipher_desc *desc,
 			    struct blkcipher_walk *walk)
 {
 	struct cast5_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 	u8 *ctrblk = walk->iv;
 	u8 keystream[CAST5_BLOCK_SIZE];
 	u8 *src = walk->src.virt.addr;
 	u8 *dst = walk->dst.virt.addr;
 	unsigned int nbytes = walk->nbytes;

 	__cast5_encrypt(ctx, keystream, ctrblk);
 	crypto_xor(keystream, src, nbytes);
 	memcpy(dst, keystream, nbytes);

 	crypto_inc(ctrblk, CAST5_BLOCK_SIZE);
 }

 static unsigned int __ctr_crypt(struct blkcipher_desc *desc,
 				struct blkcipher_walk *walk)
 {
 	struct cast5_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 	const unsigned int bsize = CAST5_BLOCK_SIZE;
 	unsigned int nbytes = walk->nbytes;
 	u64 *src = (u64 *)walk->src.virt.addr;
 	u64 *dst = (u64 *)walk->dst.virt.addr;

 	/* Process multi-block batch */
 	if (nbytes >= bsize * CAST5_PARALLEL_BLOCKS) {
 		do {
 			cast5_ctr_16way(ctx, (u8 *)dst, (u8 *)src,
 					(__be64 *)walk->iv);

 			src += CAST5_PARALLEL_BLOCKS;
 			dst += CAST5_PARALLEL_BLOCKS;
 			nbytes -= bsize * CAST5_PARALLEL_BLOCKS;
 		} while (nbytes >= bsize * CAST5_PARALLEL_BLOCKS);

 		if (nbytes < bsize)
 			goto done;
 	}

 	/* Handle leftovers */
 	do {
 		u64 ctrblk;

 		if (dst != src)
 			*dst = *src;

 		ctrblk = *(u64 *)walk->iv;
 		be64_add_cpu((__be64 *)walk->iv, 1);

 		__cast5_encrypt(ctx, (u8 *)&ctrblk, (u8 *)&ctrblk);
 		*dst ^= ctrblk;

 		src += 1;
 		dst += 1;
 		nbytes -= bsize;
 	} while (nbytes >= bsize);

 done:
 	return nbytes;
 }

 static int ctr_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 		     struct scatterlist *src, unsigned int nbytes)
 {
 	bool fpu_enabled = false;
 	struct blkcipher_walk walk;
 	int err;

 	blkcipher_walk_init(&walk, dst, src, nbytes);
 	err = blkcipher_walk_virt_block(desc, &walk, CAST5_BLOCK_SIZE);
 	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;

 	while ((nbytes = walk.nbytes) >= CAST5_BLOCK_SIZE) {
 		fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes);
 		nbytes = __ctr_crypt(desc, &walk);
 		err = blkcipher_walk_done(desc, &walk, nbytes);
 	}

 	cast5_fpu_end(fpu_enabled);

 	if (walk.nbytes) {
 		ctr_crypt_final(desc, &walk);
 		err = blkcipher_walk_done(desc, &walk, 0);
 	}

 	return err;
 }


 static struct crypto_alg cast5_algs[6] = { {
 	.cra_name		= "__ecb-cast5-avx",
 	.cra_driver_name	= "__driver-ecb-cast5-avx",
 	.cra_priority		= 0,
 	.cra_flags		= CRYPTO_ALG_TYPE_BLKCIPHER,
 	.cra_blocksize		= CAST5_BLOCK_SIZE,
 	.cra_ctxsize		= sizeof(struct cast5_ctx),
 	.cra_alignmask		= 0,
 	.cra_type		= &crypto_blkcipher_type,
 	.cra_module		= THIS_MODULE,
 	.cra_u = {
 		.blkcipher = {
 			.min_keysize	= CAST5_MIN_KEY_SIZE,
 			.max_keysize	= CAST5_MAX_KEY_SIZE,
 			.setkey		= cast5_setkey,
 			.encrypt	= ecb_encrypt,
 			.decrypt	= ecb_decrypt,
 		},
 	},
 }, {
 	.cra_name		= "__cbc-cast5-avx",
 	.cra_driver_name	= "__driver-cbc-cast5-avx",
 	.cra_priority		= 0,
 	.cra_flags		= CRYPTO_ALG_TYPE_BLKCIPHER,
 	.cra_blocksize		= CAST5_BLOCK_SIZE,
 	.cra_ctxsize		= sizeof(struct cast5_ctx),
 	.cra_alignmask		= 0,
 	.cra_type		= &crypto_blkcipher_type,
 	.cra_module		= THIS_MODULE,
 	.cra_u = {
 		.blkcipher = {
 			.min_keysize	= CAST5_MIN_KEY_SIZE,
 			.max_keysize	= CAST5_MAX_KEY_SIZE,
 			.setkey		= cast5_setkey,
 			.encrypt	= cbc_encrypt,
 			.decrypt	= cbc_decrypt,
 		},
 	},
 }, {
 	.cra_name		= "__ctr-cast5-avx",
 	.cra_driver_name	= "__driver-ctr-cast5-avx",
 	.cra_priority		= 0,
 	.cra_flags		= CRYPTO_ALG_TYPE_BLKCIPHER,
 	.cra_blocksize		= 1,
 	.cra_ctxsize		= sizeof(struct cast5_ctx),
 	.cra_alignmask		= 0,
 	.cra_type		= &crypto_blkcipher_type,
 	.cra_module		= THIS_MODULE,
 	.cra_u = {
 		.blkcipher = {
 			.min_keysize	= CAST5_MIN_KEY_SIZE,
 			.max_keysize	= CAST5_MAX_KEY_SIZE,
 			.ivsize		= CAST5_BLOCK_SIZE,
 			.setkey		= cast5_setkey,
 			.encrypt	= ctr_crypt,
 			.decrypt	= ctr_crypt,
 		},
 	},
 }, {
 	.cra_name		= "ecb(cast5)",
 	.cra_driver_name	= "ecb-cast5-avx",
 	.cra_priority		= 200,
 	.cra_flags		= CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
 	.cra_blocksize		= CAST5_BLOCK_SIZE,
 	.cra_ctxsize		= sizeof(struct async_helper_ctx),
 	.cra_alignmask		= 0,
 	.cra_type		= &crypto_ablkcipher_type,
 	.cra_module		= THIS_MODULE,
 	.cra_init		= ablk_init,
 	.cra_exit		= ablk_exit,
 	.cra_u = {
 		.ablkcipher = {
 			.min_keysize	= CAST5_MIN_KEY_SIZE,
 			.max_keysize	= CAST5_MAX_KEY_SIZE,
 			.setkey		= ablk_set_key,
 			.encrypt	= ablk_encrypt,
 			.decrypt	= ablk_decrypt,
 		},
 	},
 }, {
 	.cra_name		= "cbc(cast5)",
 	.cra_driver_name	= "cbc-cast5-avx",
 	.cra_priority		= 200,
 	.cra_flags		= CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
 	.cra_blocksize		= CAST5_BLOCK_SIZE,
 	.cra_ctxsize		= sizeof(struct async_helper_ctx),
 	.cra_alignmask		= 0,
 	.cra_type		= &crypto_ablkcipher_type,
 	.cra_module		= THIS_MODULE,
 	.cra_init		= ablk_init,
 	.cra_exit		= ablk_exit,
 	.cra_u = {
 		.ablkcipher = {
 			.min_keysize	= CAST5_MIN_KEY_SIZE,
 			.max_keysize	= CAST5_MAX_KEY_SIZE,
 			.ivsize		= CAST5_BLOCK_SIZE,
 			.setkey		= ablk_set_key,
 			.encrypt	= __ablk_encrypt,
 			.decrypt	= ablk_decrypt,
 		},
 	},
 }, {
 	.cra_name		= "ctr(cast5)",
 	.cra_driver_name	= "ctr-cast5-avx",
 	.cra_priority		= 200,
 	.cra_flags		= CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
 	.cra_blocksize		= 1,
 	.cra_ctxsize		= sizeof(struct async_helper_ctx),
 	.cra_alignmask		= 0,
 	.cra_type		= &crypto_ablkcipher_type,
 	.cra_module		= THIS_MODULE,
 	.cra_init		= ablk_init,
 	.cra_exit		= ablk_exit,
 	.cra_u = {
 		.ablkcipher = {
 			.min_keysize	= CAST5_MIN_KEY_SIZE,
 			.max_keysize	= CAST5_MAX_KEY_SIZE,
 			.ivsize		= CAST5_BLOCK_SIZE,
 			.setkey		= ablk_set_key,
 			.encrypt	= ablk_encrypt,
 			.decrypt	= ablk_encrypt,
 			.geniv		= "chainiv",
 		},
 	},
 } };

 static int __init cast5_init(void)
 {
 	u64 xcr0;

 	if (!cpu_has_avx || !cpu_has_osxsave) {
 		pr_info("AVX instructions are not detected.\n");
 		return -ENODEV;
 	}

 	xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK);
 	if ((xcr0 & (XSTATE_SSE | XSTATE_YMM)) != (XSTATE_SSE | XSTATE_YMM)) {
 		pr_info("AVX detected but unusable.\n");
 		return -ENODEV;
 	}

 	return crypto_register_algs(cast5_algs, ARRAY_SIZE(cast5_algs));
 }

 static void __exit cast5_exit(void)
 {
 	crypto_unregister_algs(cast5_algs, ARRAY_SIZE(cast5_algs));
 }

 module_init(cast5_init);
 module_exit(cast5_exit);

 MODULE_DESCRIPTION("Cast5 Cipher Algorithm, AVX optimized");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS_CRYPTO("cast5");
	/*
	* Glue Code for the AVX assembler implemention of the Cast5 Cipher
	*
	* Copyright (C) 2012 Johannes Goetzfried
	* <Johannes.Goetzfried@informatik.stud.uni-erlangen.de>
	*
	* 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.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
	* USA
	*
	*/

	#include <linux/module.h>
	#include <linux/hardirq.h>
	#include <linux/types.h>
	#include <linux/crypto.h>
	#include <linux/err.h>
	#include <crypto/ablk_helper.h>
	#include <crypto/algapi.h>
	#include <crypto/cast5.h>
	#include <crypto/cryptd.h>
	#include <crypto/ctr.h>
	#include <asm/xcr.h>
	#include <asm/xsave.h>
	#include <asm/crypto/glue_helper.h>

	#define CAST5_PARALLEL_BLOCKS 16

	asmlinkage void cast5_ecb_enc_16way(struct cast5_ctx ctx, u8 dst,
	const u8 *src);
	asmlinkage void cast5_ecb_dec_16way(struct cast5_ctx ctx, u8 dst,
	const u8 *src);
	asmlinkage void cast5_cbc_dec_16way(struct cast5_ctx ctx, u8 dst,
	const u8 *src);
	asmlinkage void cast5_ctr_16way(struct cast5_ctx ctx, u8 dst, const u8 *src,
	__be64 *iv);

	static inline bool cast5_fpu_begin(bool fpu_enabled, unsigned int nbytes)
	{
	return glue_fpu_begin(CAST5_BLOCK_SIZE, CAST5_PARALLEL_BLOCKS,
	NULL, fpu_enabled, nbytes);
	}

	static inline void cast5_fpu_end(bool fpu_enabled)
	{
	return glue_fpu_end(fpu_enabled);
	}

	static int ecb_crypt(struct blkcipher_desc desc, struct blkcipher_walk walk,
	bool enc)
	{
	bool fpu_enabled = false;
	struct cast5_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	const unsigned int bsize = CAST5_BLOCK_SIZE;
	unsigned int nbytes;
	void (fn)(struct cast5_ctx ctx, u8 dst, const u8 src);
	int err;

	fn = (enc) ? cast5_ecb_enc_16way : cast5_ecb_dec_16way;

	err = blkcipher_walk_virt(desc, walk);
	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;

	while ((nbytes = walk->nbytes)) {
	u8 *wsrc = walk->src.virt.addr;
	u8 *wdst = walk->dst.virt.addr;

	fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes);

	/* Process multi-block batch */
	if (nbytes >= bsize * CAST5_PARALLEL_BLOCKS) {
	do {
	fn(ctx, wdst, wsrc);

	wsrc += bsize * CAST5_PARALLEL_BLOCKS;
	wdst += bsize * CAST5_PARALLEL_BLOCKS;
	nbytes -= bsize * CAST5_PARALLEL_BLOCKS;
	} while (nbytes >= bsize * CAST5_PARALLEL_BLOCKS);

	if (nbytes < bsize)
	goto done;
	}

	fn = (enc) ? __cast5_encrypt : __cast5_decrypt;

	/* Handle leftovers */
	do {
	fn(ctx, wdst, wsrc);

	wsrc += bsize;
	wdst += bsize;
	nbytes -= bsize;
	} while (nbytes >= bsize);

	done:
	err = blkcipher_walk_done(desc, walk, nbytes);
	}

	cast5_fpu_end(fpu_enabled);
	return err;
	}

	static int ecb_encrypt(struct blkcipher_desc desc, struct scatterlist dst,
	struct scatterlist *src, unsigned int nbytes)
	{
	struct blkcipher_walk walk;

	blkcipher_walk_init(&walk, dst, src, nbytes);
	return ecb_crypt(desc, &walk, true);
	}

	static int ecb_decrypt(struct blkcipher_desc desc, struct scatterlist dst,
	struct scatterlist *src, unsigned int nbytes)
	{
	struct blkcipher_walk walk;

	blkcipher_walk_init(&walk, dst, src, nbytes);
	return ecb_crypt(desc, &walk, false);
	}

	static unsigned int __cbc_encrypt(struct blkcipher_desc *desc,
	struct blkcipher_walk *walk)
	{
	struct cast5_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	const unsigned int bsize = CAST5_BLOCK_SIZE;
	unsigned int nbytes = walk->nbytes;
	u64 src = (u64 )walk->src.virt.addr;
	u64 dst = (u64 )walk->dst.virt.addr;
	u64 iv = (u64 )walk->iv;

	do {
	dst = src ^ *iv;
	__cast5_encrypt(ctx, (u8 )dst, (u8 )dst);
	iv = dst;

	src += 1;
	dst += 1;
	nbytes -= bsize;
	} while (nbytes >= bsize);

	(u64 )walk->iv = *iv;
	return nbytes;
	}

	static int cbc_encrypt(struct blkcipher_desc desc, struct scatterlist dst,
	struct scatterlist *src, unsigned int nbytes)
	{
	struct blkcipher_walk walk;
	int err;

	blkcipher_walk_init(&walk, dst, src, nbytes);
	err = blkcipher_walk_virt(desc, &walk);

	while ((nbytes = walk.nbytes)) {
	nbytes = __cbc_encrypt(desc, &walk);
	err = blkcipher_walk_done(desc, &walk, nbytes);
	}

	return err;
	}

	static unsigned int __cbc_decrypt(struct blkcipher_desc *desc,
	struct blkcipher_walk *walk)
	{
	struct cast5_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	const unsigned int bsize = CAST5_BLOCK_SIZE;
	unsigned int nbytes = walk->nbytes;
	u64 src = (u64 )walk->src.virt.addr;
	u64 dst = (u64 )walk->dst.virt.addr;
	u64 last_iv;

	/* Start of the last block. */
	src += nbytes / bsize - 1;
	dst += nbytes / bsize - 1;

	last_iv = *src;

	/* Process multi-block batch */
	if (nbytes >= bsize * CAST5_PARALLEL_BLOCKS) {
	do {
	nbytes -= bsize * (CAST5_PARALLEL_BLOCKS - 1);
	src -= CAST5_PARALLEL_BLOCKS - 1;
	dst -= CAST5_PARALLEL_BLOCKS - 1;

	cast5_cbc_dec_16way(ctx, (u8 )dst, (u8 )src);

	nbytes -= bsize;
	if (nbytes < bsize)
	goto done;

	dst ^= (src - 1);
	src -= 1;
	dst -= 1;
	} while (nbytes >= bsize * CAST5_PARALLEL_BLOCKS);
	}

	/* Handle leftovers */
	for (;;) {
	__cast5_decrypt(ctx, (u8 )dst, (u8 )src);

	nbytes -= bsize;
	if (nbytes < bsize)
	break;

	dst ^= (src - 1);
	src -= 1;
	dst -= 1;
	}

	done:
	dst ^= (u64 *)walk->iv;
	(u64 )walk->iv = last_iv;

	return nbytes;
	}

	static int cbc_decrypt(struct blkcipher_desc desc, struct scatterlist dst,
	struct scatterlist *src, unsigned int nbytes)
	{
	bool fpu_enabled = false;
	struct blkcipher_walk walk;
	int err;

	blkcipher_walk_init(&walk, dst, src, nbytes);
	err = blkcipher_walk_virt(desc, &walk);
	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;

	while ((nbytes = walk.nbytes)) {
	fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes);
	nbytes = __cbc_decrypt(desc, &walk);
	err = blkcipher_walk_done(desc, &walk, nbytes);
	}

	cast5_fpu_end(fpu_enabled);
	return err;
	}

	static void ctr_crypt_final(struct blkcipher_desc *desc,
	struct blkcipher_walk *walk)
	{
	struct cast5_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	u8 *ctrblk = walk->iv;
	u8 keystream[CAST5_BLOCK_SIZE];
	u8 *src = walk->src.virt.addr;
	u8 *dst = walk->dst.virt.addr;
	unsigned int nbytes = walk->nbytes;

	__cast5_encrypt(ctx, keystream, ctrblk);
	crypto_xor(keystream, src, nbytes);
	memcpy(dst, keystream, nbytes);

	crypto_inc(ctrblk, CAST5_BLOCK_SIZE);
	}

	static unsigned int __ctr_crypt(struct blkcipher_desc *desc,
	struct blkcipher_walk *walk)
	{
	struct cast5_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	const unsigned int bsize = CAST5_BLOCK_SIZE;
	unsigned int nbytes = walk->nbytes;
	u64 src = (u64 )walk->src.virt.addr;
	u64 dst = (u64 )walk->dst.virt.addr;

	/* Process multi-block batch */
	if (nbytes >= bsize * CAST5_PARALLEL_BLOCKS) {
	do {
	cast5_ctr_16way(ctx, (u8 )dst, (u8 )src,
	(__be64 *)walk->iv);

	src += CAST5_PARALLEL_BLOCKS;
	dst += CAST5_PARALLEL_BLOCKS;
	nbytes -= bsize * CAST5_PARALLEL_BLOCKS;
	} while (nbytes >= bsize * CAST5_PARALLEL_BLOCKS);

	if (nbytes < bsize)
	goto done;
	}

	/* Handle leftovers */
	do {
	u64 ctrblk;

	if (dst != src)
	dst = src;

	ctrblk = (u64 )walk->iv;
	be64_add_cpu((__be64 *)walk->iv, 1);

	__cast5_encrypt(ctx, (u8 )&ctrblk, (u8 )&ctrblk);
	*dst ^= ctrblk;

	src += 1;
	dst += 1;
	nbytes -= bsize;
	} while (nbytes >= bsize);

	done:
	return nbytes;
	}

	static int ctr_crypt(struct blkcipher_desc desc, struct scatterlist dst,
	struct scatterlist *src, unsigned int nbytes)
	{
	bool fpu_enabled = false;
	struct blkcipher_walk walk;
	int err;

	blkcipher_walk_init(&walk, dst, src, nbytes);
	err = blkcipher_walk_virt_block(desc, &walk, CAST5_BLOCK_SIZE);
	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;

	while ((nbytes = walk.nbytes) >= CAST5_BLOCK_SIZE) {
	fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes);
	nbytes = __ctr_crypt(desc, &walk);
	err = blkcipher_walk_done(desc, &walk, nbytes);
	}

	cast5_fpu_end(fpu_enabled);

	if (walk.nbytes) {
	ctr_crypt_final(desc, &walk);
	err = blkcipher_walk_done(desc, &walk, 0);
	}

	return err;
	}


	static struct crypto_alg cast5_algs[6] = { {
	.cra_name = "__ecb-cast5-avx",
	.cra_driver_name = "__driver-ecb-cast5-avx",
	.cra_priority = 0,
	.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
	.cra_blocksize = CAST5_BLOCK_SIZE,
	.cra_ctxsize = sizeof(struct cast5_ctx),
	.cra_alignmask = 0,
	.cra_type = &crypto_blkcipher_type,
	.cra_module = THIS_MODULE,
	.cra_u = {
	.blkcipher = {
	.min_keysize = CAST5_MIN_KEY_SIZE,
	.max_keysize = CAST5_MAX_KEY_SIZE,
	.setkey = cast5_setkey,
	.encrypt = ecb_encrypt,
	.decrypt = ecb_decrypt,
	},
	},
	}, {
	.cra_name = "__cbc-cast5-avx",
	.cra_driver_name = "__driver-cbc-cast5-avx",
	.cra_priority = 0,
	.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
	.cra_blocksize = CAST5_BLOCK_SIZE,
	.cra_ctxsize = sizeof(struct cast5_ctx),
	.cra_alignmask = 0,
	.cra_type = &crypto_blkcipher_type,
	.cra_module = THIS_MODULE,
	.cra_u = {
	.blkcipher = {
	.min_keysize = CAST5_MIN_KEY_SIZE,
	.max_keysize = CAST5_MAX_KEY_SIZE,
	.setkey = cast5_setkey,
	.encrypt = cbc_encrypt,
	.decrypt = cbc_decrypt,
	},
	},
	}, {
	.cra_name = "__ctr-cast5-avx",
	.cra_driver_name = "__driver-ctr-cast5-avx",
	.cra_priority = 0,
	.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
	.cra_blocksize = 1,
	.cra_ctxsize = sizeof(struct cast5_ctx),
	.cra_alignmask = 0,
	.cra_type = &crypto_blkcipher_type,
	.cra_module = THIS_MODULE,
	.cra_u = {
	.blkcipher = {
	.min_keysize = CAST5_MIN_KEY_SIZE,
	.max_keysize = CAST5_MAX_KEY_SIZE,
	.ivsize = CAST5_BLOCK_SIZE,
	.setkey = cast5_setkey,
	.encrypt = ctr_crypt,
	.decrypt = ctr_crypt,
	},
	},
	}, {
	.cra_name = "ecb(cast5)",
	.cra_driver_name = "ecb-cast5-avx",
	.cra_priority = 200,
	.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER \| CRYPTO_ALG_ASYNC,
	.cra_blocksize = CAST5_BLOCK_SIZE,
	.cra_ctxsize = sizeof(struct async_helper_ctx),
	.cra_alignmask = 0,
	.cra_type = &crypto_ablkcipher_type,
	.cra_module = THIS_MODULE,
	.cra_init = ablk_init,
	.cra_exit = ablk_exit,
	.cra_u = {
	.ablkcipher = {
	.min_keysize = CAST5_MIN_KEY_SIZE,
	.max_keysize = CAST5_MAX_KEY_SIZE,
	.setkey = ablk_set_key,
	.encrypt = ablk_encrypt,
	.decrypt = ablk_decrypt,
	},
	},
	}, {
	.cra_name = "cbc(cast5)",
	.cra_driver_name = "cbc-cast5-avx",
	.cra_priority = 200,
	.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER \| CRYPTO_ALG_ASYNC,
	.cra_blocksize = CAST5_BLOCK_SIZE,
	.cra_ctxsize = sizeof(struct async_helper_ctx),
	.cra_alignmask = 0,
	.cra_type = &crypto_ablkcipher_type,
	.cra_module = THIS_MODULE,
	.cra_init = ablk_init,
	.cra_exit = ablk_exit,
	.cra_u = {
	.ablkcipher = {
	.min_keysize = CAST5_MIN_KEY_SIZE,
	.max_keysize = CAST5_MAX_KEY_SIZE,
	.ivsize = CAST5_BLOCK_SIZE,
	.setkey = ablk_set_key,
	.encrypt = __ablk_encrypt,
	.decrypt = ablk_decrypt,
	},
	},
	}, {
	.cra_name = "ctr(cast5)",
	.cra_driver_name = "ctr-cast5-avx",
	.cra_priority = 200,
	.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER \| CRYPTO_ALG_ASYNC,
	.cra_blocksize = 1,
	.cra_ctxsize = sizeof(struct async_helper_ctx),
	.cra_alignmask = 0,
	.cra_type = &crypto_ablkcipher_type,
	.cra_module = THIS_MODULE,
	.cra_init = ablk_init,
	.cra_exit = ablk_exit,
	.cra_u = {
	.ablkcipher = {
	.min_keysize = CAST5_MIN_KEY_SIZE,
	.max_keysize = CAST5_MAX_KEY_SIZE,
	.ivsize = CAST5_BLOCK_SIZE,
	.setkey = ablk_set_key,
	.encrypt = ablk_encrypt,
	.decrypt = ablk_encrypt,
	.geniv = "chainiv",
	},
	},
	} };

	static int __init cast5_init(void)
	{
	u64 xcr0;

	if (!cpu_has_avx \|\| !cpu_has_osxsave) {
	pr_info("AVX instructions are not detected.\n");
	return -ENODEV;
	}

	xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK);
	if ((xcr0 & (XSTATE_SSE \| XSTATE_YMM)) != (XSTATE_SSE \| XSTATE_YMM)) {
	pr_info("AVX detected but unusable.\n");
	return -ENODEV;
	}

	return crypto_register_algs(cast5_algs, ARRAY_SIZE(cast5_algs));
	}

	static void __exit cast5_exit(void)
	{
	crypto_unregister_algs(cast5_algs, ARRAY_SIZE(cast5_algs));
	}

	module_init(cast5_init);
	module_exit(cast5_exit);

	MODULE_DESCRIPTION("Cast5 Cipher Algorithm, AVX optimized");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS_CRYPTO("cast5");