diff options
Diffstat (limited to 'arch/x86/crypto/glue_helper.c')
| -rw-r--r-- | arch/x86/crypto/glue_helper.c | 307 | 
1 files changed, 307 insertions, 0 deletions
diff --git a/arch/x86/crypto/glue_helper.c b/arch/x86/crypto/glue_helper.c new file mode 100644 index 00000000000..4854f0f31e4 --- /dev/null +++ b/arch/x86/crypto/glue_helper.c @@ -0,0 +1,307 @@ +/* + * Shared glue code for 128bit block ciphers + * + * Copyright (c) 2012 Jussi Kivilinna <jussi.kivilinna@mbnet.fi> + * + * CBC & ECB parts based on code (crypto/cbc.c,ecb.c) by: + *   Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au> + * CTR part based on code (crypto/ctr.c) by: + *   (C) Copyright IBM Corp. 2007 - Joy Latten <latten@us.ibm.com> + * + * 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 <crypto/b128ops.h> +#include <crypto/lrw.h> +#include <crypto/xts.h> +#include <asm/crypto/glue_helper.h> +#include <crypto/scatterwalk.h> + +static int __glue_ecb_crypt_128bit(const struct common_glue_ctx *gctx, +				   struct blkcipher_desc *desc, +				   struct blkcipher_walk *walk) +{ +	void *ctx = crypto_blkcipher_ctx(desc->tfm); +	const unsigned int bsize = 128 / 8; +	unsigned int nbytes, i, func_bytes; +	bool fpu_enabled = false; +	int err; + +	err = blkcipher_walk_virt(desc, walk); + +	while ((nbytes = walk->nbytes)) { +		u8 *wsrc = walk->src.virt.addr; +		u8 *wdst = walk->dst.virt.addr; + +		fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, +					     desc, fpu_enabled, nbytes); + +		for (i = 0; i < gctx->num_funcs; i++) { +			func_bytes = bsize * gctx->funcs[i].num_blocks; + +			/* Process multi-block batch */ +			if (nbytes >= func_bytes) { +				do { +					gctx->funcs[i].fn_u.ecb(ctx, wdst, +								wsrc); + +					wsrc += func_bytes; +					wdst += func_bytes; +					nbytes -= func_bytes; +				} while (nbytes >= func_bytes); + +				if (nbytes < bsize) +					goto done; +			} +		} + +done: +		err = blkcipher_walk_done(desc, walk, nbytes); +	} + +	glue_fpu_end(fpu_enabled); +	return err; +} + +int glue_ecb_crypt_128bit(const struct common_glue_ctx *gctx, +			  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 __glue_ecb_crypt_128bit(gctx, desc, &walk); +} +EXPORT_SYMBOL_GPL(glue_ecb_crypt_128bit); + +static unsigned int __glue_cbc_encrypt_128bit(const common_glue_func_t fn, +					      struct blkcipher_desc *desc, +					      struct blkcipher_walk *walk) +{ +	void *ctx = crypto_blkcipher_ctx(desc->tfm); +	const unsigned int bsize = 128 / 8; +	unsigned int nbytes = walk->nbytes; +	u128 *src = (u128 *)walk->src.virt.addr; +	u128 *dst = (u128 *)walk->dst.virt.addr; +	u128 *iv = (u128 *)walk->iv; + +	do { +		u128_xor(dst, src, iv); +		fn(ctx, (u8 *)dst, (u8 *)dst); +		iv = dst; + +		src += 1; +		dst += 1; +		nbytes -= bsize; +	} while (nbytes >= bsize); + +	u128_xor((u128 *)walk->iv, (u128 *)walk->iv, iv); +	return nbytes; +} + +int glue_cbc_encrypt_128bit(const common_glue_func_t fn, +			    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 = __glue_cbc_encrypt_128bit(fn, desc, &walk); +		err = blkcipher_walk_done(desc, &walk, nbytes); +	} + +	return err; +} +EXPORT_SYMBOL_GPL(glue_cbc_encrypt_128bit); + +static unsigned int +__glue_cbc_decrypt_128bit(const struct common_glue_ctx *gctx, +			  struct blkcipher_desc *desc, +			  struct blkcipher_walk *walk) +{ +	void *ctx = crypto_blkcipher_ctx(desc->tfm); +	const unsigned int bsize = 128 / 8; +	unsigned int nbytes = walk->nbytes; +	u128 *src = (u128 *)walk->src.virt.addr; +	u128 *dst = (u128 *)walk->dst.virt.addr; +	u128 last_iv; +	unsigned int num_blocks, func_bytes; +	unsigned int i; + +	/* Start of the last block. */ +	src += nbytes / bsize - 1; +	dst += nbytes / bsize - 1; + +	last_iv = *src; + +	for (i = 0; i < gctx->num_funcs; i++) { +		num_blocks = gctx->funcs[i].num_blocks; +		func_bytes = bsize * num_blocks; + +		/* Process multi-block batch */ +		if (nbytes >= func_bytes) { +			do { +				nbytes -= func_bytes - bsize; +				src -= num_blocks - 1; +				dst -= num_blocks - 1; + +				gctx->funcs[i].fn_u.cbc(ctx, dst, src); + +				nbytes -= bsize; +				if (nbytes < bsize) +					goto done; + +				u128_xor(dst, dst, src - 1); +				src -= 1; +				dst -= 1; +			} while (nbytes >= func_bytes); + +			if (nbytes < bsize) +				goto done; +		} +	} + +done: +	u128_xor(dst, dst, (u128 *)walk->iv); +	*(u128 *)walk->iv = last_iv; + +	return nbytes; +} + +int glue_cbc_decrypt_128bit(const struct common_glue_ctx *gctx, +			    struct blkcipher_desc *desc, +			    struct scatterlist *dst, +			    struct scatterlist *src, unsigned int nbytes) +{ +	const unsigned int bsize = 128 / 8; +	bool fpu_enabled = false; +	struct blkcipher_walk walk; +	int err; + +	blkcipher_walk_init(&walk, dst, src, nbytes); +	err = blkcipher_walk_virt(desc, &walk); + +	while ((nbytes = walk.nbytes)) { +		fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, +					     desc, fpu_enabled, nbytes); +		nbytes = __glue_cbc_decrypt_128bit(gctx, desc, &walk); +		err = blkcipher_walk_done(desc, &walk, nbytes); +	} + +	glue_fpu_end(fpu_enabled); +	return err; +} +EXPORT_SYMBOL_GPL(glue_cbc_decrypt_128bit); + +static void glue_ctr_crypt_final_128bit(const common_glue_ctr_func_t fn_ctr, +					struct blkcipher_desc *desc, +					struct blkcipher_walk *walk) +{ +	void *ctx = crypto_blkcipher_ctx(desc->tfm); +	u8 *src = (u8 *)walk->src.virt.addr; +	u8 *dst = (u8 *)walk->dst.virt.addr; +	unsigned int nbytes = walk->nbytes; +	u128 ctrblk; +	u128 tmp; + +	be128_to_u128(&ctrblk, (be128 *)walk->iv); + +	memcpy(&tmp, src, nbytes); +	fn_ctr(ctx, &tmp, &tmp, &ctrblk); +	memcpy(dst, &tmp, nbytes); + +	u128_to_be128((be128 *)walk->iv, &ctrblk); +} +EXPORT_SYMBOL_GPL(glue_ctr_crypt_final_128bit); + +static unsigned int __glue_ctr_crypt_128bit(const struct common_glue_ctx *gctx, +					    struct blkcipher_desc *desc, +					    struct blkcipher_walk *walk) +{ +	const unsigned int bsize = 128 / 8; +	void *ctx = crypto_blkcipher_ctx(desc->tfm); +	unsigned int nbytes = walk->nbytes; +	u128 *src = (u128 *)walk->src.virt.addr; +	u128 *dst = (u128 *)walk->dst.virt.addr; +	u128 ctrblk; +	unsigned int num_blocks, func_bytes; +	unsigned int i; + +	be128_to_u128(&ctrblk, (be128 *)walk->iv); + +	/* Process multi-block batch */ +	for (i = 0; i < gctx->num_funcs; i++) { +		num_blocks = gctx->funcs[i].num_blocks; +		func_bytes = bsize * num_blocks; + +		if (nbytes >= func_bytes) { +			do { +				gctx->funcs[i].fn_u.ctr(ctx, dst, src, &ctrblk); + +				src += num_blocks; +				dst += num_blocks; +				nbytes -= func_bytes; +			} while (nbytes >= func_bytes); + +			if (nbytes < bsize) +				goto done; +		} +	} + +done: +	u128_to_be128((be128 *)walk->iv, &ctrblk); +	return nbytes; +} + +int glue_ctr_crypt_128bit(const struct common_glue_ctx *gctx, +			  struct blkcipher_desc *desc, struct scatterlist *dst, +			  struct scatterlist *src, unsigned int nbytes) +{ +	const unsigned int bsize = 128 / 8; +	bool fpu_enabled = false; +	struct blkcipher_walk walk; +	int err; + +	blkcipher_walk_init(&walk, dst, src, nbytes); +	err = blkcipher_walk_virt_block(desc, &walk, bsize); + +	while ((nbytes = walk.nbytes) >= bsize) { +		fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, +					     desc, fpu_enabled, nbytes); +		nbytes = __glue_ctr_crypt_128bit(gctx, desc, &walk); +		err = blkcipher_walk_done(desc, &walk, nbytes); +	} + +	glue_fpu_end(fpu_enabled); + +	if (walk.nbytes) { +		glue_ctr_crypt_final_128bit( +			gctx->funcs[gctx->num_funcs - 1].fn_u.ctr, desc, &walk); +		err = blkcipher_walk_done(desc, &walk, 0); +	} + +	return err; +} +EXPORT_SYMBOL_GPL(glue_ctr_crypt_128bit); + +MODULE_LICENSE("GPL");  |