crypto/cbc.c - android_kernel_htc_msm8960 - Gitiles

 /*
  * CBC: Cipher Block Chaining mode
  *
  * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
  *
  * 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.
  *
  */

 #include <crypto/algapi.h>
 #include <linux/err.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/scatterlist.h>
 #include <linux/slab.h>

 struct crypto_cbc_ctx {
 	struct crypto_cipher *child;
 	void (*xor)(u8 *dst, const u8 *src, unsigned int bs);
 };

 static int crypto_cbc_setkey(struct crypto_tfm *parent, const u8 *key,
 			     unsigned int keylen)
 {
 	struct crypto_cbc_ctx *ctx = crypto_tfm_ctx(parent);
 	struct crypto_cipher *child = ctx->child;
 	int err;

 	crypto_cipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
 	crypto_cipher_set_flags(child, crypto_tfm_get_flags(parent) &
 				       CRYPTO_TFM_REQ_MASK);
 	err = crypto_cipher_setkey(child, key, keylen);
 	crypto_tfm_set_flags(parent, crypto_cipher_get_flags(child) &
 				     CRYPTO_TFM_RES_MASK);
 	return err;
 }

 static int crypto_cbc_encrypt_segment(struct blkcipher_desc *desc,
 				      struct blkcipher_walk *walk,
 				      struct crypto_cipher *tfm,
 				      void (*xor)(u8 *, const u8 *,
 						  unsigned int))
 {
 	void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
 		crypto_cipher_alg(tfm)->cia_encrypt;
 	int bsize = crypto_cipher_blocksize(tfm);
 	unsigned int nbytes = walk->nbytes;
 	u8 *src = walk->src.virt.addr;
 	u8 *dst = walk->dst.virt.addr;
 	u8 *iv = walk->iv;

 	do {
 		xor(iv, src, bsize);
 		fn(crypto_cipher_tfm(tfm), dst, iv);
 		memcpy(iv, dst, bsize);

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

 	return nbytes;
 }

 static int crypto_cbc_encrypt_inplace(struct blkcipher_desc *desc,
 				      struct blkcipher_walk *walk,
 				      struct crypto_cipher *tfm,
 				      void (*xor)(u8 *, const u8 *,
 						  unsigned int))
 {
 	void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
 		crypto_cipher_alg(tfm)->cia_encrypt;
 	int bsize = crypto_cipher_blocksize(tfm);
 	unsigned int nbytes = walk->nbytes;
 	u8 *src = walk->src.virt.addr;
 	u8 *iv = walk->iv;

 	do {
 		xor(src, iv, bsize);
 		fn(crypto_cipher_tfm(tfm), src, src);
 		iv = src;

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

 	memcpy(walk->iv, iv, bsize);

 	return nbytes;
 }

 static int crypto_cbc_encrypt(struct blkcipher_desc *desc,
 			      struct scatterlist *dst, struct scatterlist *src,
 			      unsigned int nbytes)
 {
 	struct blkcipher_walk walk;
 	struct crypto_blkcipher *tfm = desc->tfm;
 	struct crypto_cbc_ctx *ctx = crypto_blkcipher_ctx(tfm);
 	struct crypto_cipher *child = ctx->child;
 	void (*xor)(u8 *, const u8 *, unsigned int bs) = ctx->xor;
 	int err;

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

 	while ((nbytes = walk.nbytes)) {
 		if (walk.src.virt.addr == walk.dst.virt.addr)
 			nbytes = crypto_cbc_encrypt_inplace(desc, &walk, child,
 							    xor);
 		else
 			nbytes = crypto_cbc_encrypt_segment(desc, &walk, child,
 							    xor);
 		err = blkcipher_walk_done(desc, &walk, nbytes);
 	}

 	return err;
 }

 static int crypto_cbc_decrypt_segment(struct blkcipher_desc *desc,
 				      struct blkcipher_walk *walk,
 				      struct crypto_cipher *tfm,
 				      void (*xor)(u8 *, const u8 *,
 						  unsigned int))
 {
 	void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
 		crypto_cipher_alg(tfm)->cia_decrypt;
 	int bsize = crypto_cipher_blocksize(tfm);
 	unsigned int nbytes = walk->nbytes;
 	u8 *src = walk->src.virt.addr;
 	u8 *dst = walk->dst.virt.addr;
 	u8 *iv = walk->iv;

 	do {
 		fn(crypto_cipher_tfm(tfm), dst, src);
 		xor(dst, iv, bsize);
 		iv = src;

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

 	memcpy(walk->iv, iv, bsize);

 	return nbytes;
 }

 static int crypto_cbc_decrypt_inplace(struct blkcipher_desc *desc,
 				      struct blkcipher_walk *walk,
 				      struct crypto_cipher *tfm,
 				      void (*xor)(u8 *, const u8 *,
 						  unsigned int))
 {
 	void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
 		crypto_cipher_alg(tfm)->cia_decrypt;
 	int bsize = crypto_cipher_blocksize(tfm);
 	unsigned long alignmask = crypto_cipher_alignmask(tfm);
 	unsigned int nbytes = walk->nbytes;
 	u8 *src = walk->src.virt.addr;
 	u8 stack[bsize + alignmask];
 	u8 *first_iv = (u8 *)ALIGN((unsigned long)stack, alignmask + 1);

 	memcpy(first_iv, walk->iv, bsize);

 	/* Start of the last block. */
 	src += nbytes - nbytes % bsize - bsize;
 	memcpy(walk->iv, src, bsize);

 	for (;;) {
 		fn(crypto_cipher_tfm(tfm), src, src);
 		if ((nbytes -= bsize) < bsize)
 			break;
 		xor(src, src - bsize, bsize);
 		src -= bsize;
 	}

 	xor(src, first_iv, bsize);

 	return nbytes;
 }

 static int crypto_cbc_decrypt(struct blkcipher_desc *desc,
 			      struct scatterlist *dst, struct scatterlist *src,
 			      unsigned int nbytes)
 {
 	struct blkcipher_walk walk;
 	struct crypto_blkcipher *tfm = desc->tfm;
 	struct crypto_cbc_ctx *ctx = crypto_blkcipher_ctx(tfm);
 	struct crypto_cipher *child = ctx->child;
 	void (*xor)(u8 *, const u8 *, unsigned int bs) = ctx->xor;
 	int err;

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

 	while ((nbytes = walk.nbytes)) {
 		if (walk.src.virt.addr == walk.dst.virt.addr)
 			nbytes = crypto_cbc_decrypt_inplace(desc, &walk, child,
 							    xor);
 		else
 			nbytes = crypto_cbc_decrypt_segment(desc, &walk, child,
 							    xor);
 		err = blkcipher_walk_done(desc, &walk, nbytes);
 	}

 	return err;
 }

 static void xor_byte(u8 *a, const u8 *b, unsigned int bs)
 {
 	do {
 		*a++ ^= *b++;
 	} while (--bs);
 }

 static void xor_quad(u8 *dst, const u8 *src, unsigned int bs)
 {
 	u32 *a = (u32 *)dst;
 	u32 *b = (u32 *)src;

 	do {
 		*a++ ^= *b++;
 	} while ((bs -= 4));
 }

 static void xor_64(u8 *a, const u8 *b, unsigned int bs)
 {
 	((u32 *)a)[0] ^= ((u32 *)b)[0];
 	((u32 *)a)[1] ^= ((u32 *)b)[1];
 }

 static void xor_128(u8 *a, const u8 *b, unsigned int bs)
 {
 	((u32 *)a)[0] ^= ((u32 *)b)[0];
 	((u32 *)a)[1] ^= ((u32 *)b)[1];
 	((u32 *)a)[2] ^= ((u32 *)b)[2];
 	((u32 *)a)[3] ^= ((u32 *)b)[3];
 }

 static int crypto_cbc_init_tfm(struct crypto_tfm *tfm)
 {
 	struct crypto_instance *inst = (void *)tfm->__crt_alg;
 	struct crypto_spawn *spawn = crypto_instance_ctx(inst);
 	struct crypto_cbc_ctx *ctx = crypto_tfm_ctx(tfm);
 	struct crypto_cipher *cipher;

 	switch (crypto_tfm_alg_blocksize(tfm)) {
 	case 8:
 		ctx->xor = xor_64;
 		break;

 	case 16:
 		ctx->xor = xor_128;
 		break;

 	default:
 		if (crypto_tfm_alg_blocksize(tfm) % 4)
 			ctx->xor = xor_byte;
 		else
 			ctx->xor = xor_quad;
 	}

 	cipher = crypto_spawn_cipher(spawn);
 	if (IS_ERR(cipher))
 		return PTR_ERR(cipher);

 	ctx->child = cipher;
 	return 0;
 }

 static void crypto_cbc_exit_tfm(struct crypto_tfm *tfm)
 {
 	struct crypto_cbc_ctx *ctx = crypto_tfm_ctx(tfm);
 	crypto_free_cipher(ctx->child);
 }

 static struct crypto_instance *crypto_cbc_alloc(void *param, unsigned int len)
 {
 	struct crypto_instance *inst;
 	struct crypto_alg *alg;

 	alg = crypto_get_attr_alg(param, len, CRYPTO_ALG_TYPE_CIPHER,
 				  CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_ASYNC);
 	if (IS_ERR(alg))
 		return ERR_PTR(PTR_ERR(alg));

 	inst = crypto_alloc_instance("cbc", alg);
 	if (IS_ERR(inst))
 		goto out_put_alg;

 	inst->alg.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER;
 	inst->alg.cra_priority = alg->cra_priority;
 	inst->alg.cra_blocksize = alg->cra_blocksize;
 	inst->alg.cra_alignmask = alg->cra_alignmask;
 	inst->alg.cra_type = &crypto_blkcipher_type;

 	if (!(alg->cra_blocksize % 4))
 		inst->alg.cra_alignmask |= 3;
 	inst->alg.cra_blkcipher.ivsize = alg->cra_blocksize;
 	inst->alg.cra_blkcipher.min_keysize = alg->cra_cipher.cia_min_keysize;
 	inst->alg.cra_blkcipher.max_keysize = alg->cra_cipher.cia_max_keysize;

 	inst->alg.cra_ctxsize = sizeof(struct crypto_cbc_ctx);

 	inst->alg.cra_init = crypto_cbc_init_tfm;
 	inst->alg.cra_exit = crypto_cbc_exit_tfm;

 	inst->alg.cra_blkcipher.setkey = crypto_cbc_setkey;
 	inst->alg.cra_blkcipher.encrypt = crypto_cbc_encrypt;
 	inst->alg.cra_blkcipher.decrypt = crypto_cbc_decrypt;

 out_put_alg:
 	crypto_mod_put(alg);
 	return inst;
 }

 static void crypto_cbc_free(struct crypto_instance *inst)
 {
 	crypto_drop_spawn(crypto_instance_ctx(inst));
 	kfree(inst);
 }

 static struct crypto_template crypto_cbc_tmpl = {
 	.name = "cbc",
 	.alloc = crypto_cbc_alloc,
 	.free = crypto_cbc_free,
 	.module = THIS_MODULE,
 };

 static int __init crypto_cbc_module_init(void)
 {
 	return crypto_register_template(&crypto_cbc_tmpl);
 }

 static void __exit crypto_cbc_module_exit(void)
 {
 	crypto_unregister_template(&crypto_cbc_tmpl);
 }

 module_init(crypto_cbc_module_init);
 module_exit(crypto_cbc_module_exit);

 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("CBC block cipher algorithm");
	/*
	* CBC: Cipher Block Chaining mode
	*
	* Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
	*
	* 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.
	*
	*/

	#include <crypto/algapi.h>
	#include <linux/err.h>
	#include <linux/init.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/scatterlist.h>
	#include <linux/slab.h>

	struct crypto_cbc_ctx {
	struct crypto_cipher *child;
	void (xor)(u8 dst, const u8 *src, unsigned int bs);
	};

	static int crypto_cbc_setkey(struct crypto_tfm parent, const u8 key,
	unsigned int keylen)
	{
	struct crypto_cbc_ctx *ctx = crypto_tfm_ctx(parent);
	struct crypto_cipher *child = ctx->child;
	int err;

	crypto_cipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
	crypto_cipher_set_flags(child, crypto_tfm_get_flags(parent) &
	CRYPTO_TFM_REQ_MASK);
	err = crypto_cipher_setkey(child, key, keylen);
	crypto_tfm_set_flags(parent, crypto_cipher_get_flags(child) &
	CRYPTO_TFM_RES_MASK);
	return err;
	}

	static int crypto_cbc_encrypt_segment(struct blkcipher_desc *desc,
	struct blkcipher_walk *walk,
	struct crypto_cipher *tfm,
	void (xor)(u8 , const u8 *,
	unsigned int))
	{
	void (fn)(struct crypto_tfm , u8 , const u8 ) =
	crypto_cipher_alg(tfm)->cia_encrypt;
	int bsize = crypto_cipher_blocksize(tfm);
	unsigned int nbytes = walk->nbytes;
	u8 *src = walk->src.virt.addr;
	u8 *dst = walk->dst.virt.addr;
	u8 *iv = walk->iv;

	do {
	xor(iv, src, bsize);
	fn(crypto_cipher_tfm(tfm), dst, iv);
	memcpy(iv, dst, bsize);

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

	return nbytes;
	}

	static int crypto_cbc_encrypt_inplace(struct blkcipher_desc *desc,
	struct blkcipher_walk *walk,
	struct crypto_cipher *tfm,
	void (xor)(u8 , const u8 *,
	unsigned int))
	{
	void (fn)(struct crypto_tfm , u8 , const u8 ) =
	crypto_cipher_alg(tfm)->cia_encrypt;
	int bsize = crypto_cipher_blocksize(tfm);
	unsigned int nbytes = walk->nbytes;
	u8 *src = walk->src.virt.addr;
	u8 *iv = walk->iv;

	do {
	xor(src, iv, bsize);
	fn(crypto_cipher_tfm(tfm), src, src);
	iv = src;

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

	memcpy(walk->iv, iv, bsize);

	return nbytes;
	}

	static int crypto_cbc_encrypt(struct blkcipher_desc *desc,
	struct scatterlist dst, struct scatterlist src,
	unsigned int nbytes)
	{
	struct blkcipher_walk walk;
	struct crypto_blkcipher *tfm = desc->tfm;
	struct crypto_cbc_ctx *ctx = crypto_blkcipher_ctx(tfm);
	struct crypto_cipher *child = ctx->child;
	void (xor)(u8 , const u8 *, unsigned int bs) = ctx->xor;
	int err;

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

	while ((nbytes = walk.nbytes)) {
	if (walk.src.virt.addr == walk.dst.virt.addr)
	nbytes = crypto_cbc_encrypt_inplace(desc, &walk, child,
	xor);
	else
	nbytes = crypto_cbc_encrypt_segment(desc, &walk, child,
	xor);
	err = blkcipher_walk_done(desc, &walk, nbytes);
	}

	return err;
	}

	static int crypto_cbc_decrypt_segment(struct blkcipher_desc *desc,
	struct blkcipher_walk *walk,
	struct crypto_cipher *tfm,
	void (xor)(u8 , const u8 *,
	unsigned int))
	{
	void (fn)(struct crypto_tfm , u8 , const u8 ) =
	crypto_cipher_alg(tfm)->cia_decrypt;
	int bsize = crypto_cipher_blocksize(tfm);
	unsigned int nbytes = walk->nbytes;
	u8 *src = walk->src.virt.addr;
	u8 *dst = walk->dst.virt.addr;
	u8 *iv = walk->iv;

	do {
	fn(crypto_cipher_tfm(tfm), dst, src);
	xor(dst, iv, bsize);
	iv = src;

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

	memcpy(walk->iv, iv, bsize);

	return nbytes;
	}

	static int crypto_cbc_decrypt_inplace(struct blkcipher_desc *desc,
	struct blkcipher_walk *walk,
	struct crypto_cipher *tfm,
	void (xor)(u8 , const u8 *,
	unsigned int))
	{
	void (fn)(struct crypto_tfm , u8 , const u8 ) =
	crypto_cipher_alg(tfm)->cia_decrypt;
	int bsize = crypto_cipher_blocksize(tfm);
	unsigned long alignmask = crypto_cipher_alignmask(tfm);
	unsigned int nbytes = walk->nbytes;
	u8 *src = walk->src.virt.addr;
	u8 stack[bsize + alignmask];
	u8 first_iv = (u8 )ALIGN((unsigned long)stack, alignmask + 1);

	memcpy(first_iv, walk->iv, bsize);

	/* Start of the last block. */
	src += nbytes - nbytes % bsize - bsize;
	memcpy(walk->iv, src, bsize);

	for (;;) {
	fn(crypto_cipher_tfm(tfm), src, src);
	if ((nbytes -= bsize) < bsize)
	break;
	xor(src, src - bsize, bsize);
	src -= bsize;
	}

	xor(src, first_iv, bsize);

	return nbytes;
	}

	static int crypto_cbc_decrypt(struct blkcipher_desc *desc,
	struct scatterlist dst, struct scatterlist src,
	unsigned int nbytes)
	{
	struct blkcipher_walk walk;
	struct crypto_blkcipher *tfm = desc->tfm;
	struct crypto_cbc_ctx *ctx = crypto_blkcipher_ctx(tfm);
	struct crypto_cipher *child = ctx->child;
	void (xor)(u8 , const u8 *, unsigned int bs) = ctx->xor;
	int err;

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

	while ((nbytes = walk.nbytes)) {
	if (walk.src.virt.addr == walk.dst.virt.addr)
	nbytes = crypto_cbc_decrypt_inplace(desc, &walk, child,
	xor);
	else
	nbytes = crypto_cbc_decrypt_segment(desc, &walk, child,
	xor);
	err = blkcipher_walk_done(desc, &walk, nbytes);
	}

	return err;
	}

	static void xor_byte(u8 a, const u8 b, unsigned int bs)
	{
	do {
	a++ ^= b++;
	} while (--bs);
	}

	static void xor_quad(u8 dst, const u8 src, unsigned int bs)
	{
	u32 a = (u32 )dst;
	u32 b = (u32 )src;

	do {
	a++ ^= b++;
	} while ((bs -= 4));
	}

	static void xor_64(u8 a, const u8 b, unsigned int bs)
	{
	((u32 )a)[0] ^= ((u32 )b)[0];
	((u32 )a)[1] ^= ((u32 )b)[1];
	}

	static void xor_128(u8 a, const u8 b, unsigned int bs)
	{
	((u32 )a)[0] ^= ((u32 )b)[0];
	((u32 )a)[1] ^= ((u32 )b)[1];
	((u32 )a)[2] ^= ((u32 )b)[2];
	((u32 )a)[3] ^= ((u32 )b)[3];
	}

	static int crypto_cbc_init_tfm(struct crypto_tfm *tfm)
	{
	struct crypto_instance inst = (void )tfm->__crt_alg;
	struct crypto_spawn *spawn = crypto_instance_ctx(inst);
	struct crypto_cbc_ctx *ctx = crypto_tfm_ctx(tfm);
	struct crypto_cipher *cipher;

	switch (crypto_tfm_alg_blocksize(tfm)) {
	case 8:
	ctx->xor = xor_64;
	break;

	case 16:
	ctx->xor = xor_128;
	break;

	default:
	if (crypto_tfm_alg_blocksize(tfm) % 4)
	ctx->xor = xor_byte;
	else
	ctx->xor = xor_quad;
	}

	cipher = crypto_spawn_cipher(spawn);
	if (IS_ERR(cipher))
	return PTR_ERR(cipher);

	ctx->child = cipher;
	return 0;
	}

	static void crypto_cbc_exit_tfm(struct crypto_tfm *tfm)
	{
	struct crypto_cbc_ctx *ctx = crypto_tfm_ctx(tfm);
	crypto_free_cipher(ctx->child);
	}

	static struct crypto_instance crypto_cbc_alloc(void param, unsigned int len)
	{
	struct crypto_instance *inst;
	struct crypto_alg *alg;

	alg = crypto_get_attr_alg(param, len, CRYPTO_ALG_TYPE_CIPHER,
	CRYPTO_ALG_TYPE_MASK \| CRYPTO_ALG_ASYNC);
	if (IS_ERR(alg))
	return ERR_PTR(PTR_ERR(alg));

	inst = crypto_alloc_instance("cbc", alg);
	if (IS_ERR(inst))
	goto out_put_alg;

	inst->alg.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER;
	inst->alg.cra_priority = alg->cra_priority;
	inst->alg.cra_blocksize = alg->cra_blocksize;
	inst->alg.cra_alignmask = alg->cra_alignmask;
	inst->alg.cra_type = &crypto_blkcipher_type;

	if (!(alg->cra_blocksize % 4))
	inst->alg.cra_alignmask \|= 3;
	inst->alg.cra_blkcipher.ivsize = alg->cra_blocksize;
	inst->alg.cra_blkcipher.min_keysize = alg->cra_cipher.cia_min_keysize;
	inst->alg.cra_blkcipher.max_keysize = alg->cra_cipher.cia_max_keysize;

	inst->alg.cra_ctxsize = sizeof(struct crypto_cbc_ctx);

	inst->alg.cra_init = crypto_cbc_init_tfm;
	inst->alg.cra_exit = crypto_cbc_exit_tfm;

	inst->alg.cra_blkcipher.setkey = crypto_cbc_setkey;
	inst->alg.cra_blkcipher.encrypt = crypto_cbc_encrypt;
	inst->alg.cra_blkcipher.decrypt = crypto_cbc_decrypt;

	out_put_alg:
	crypto_mod_put(alg);
	return inst;
	}

	static void crypto_cbc_free(struct crypto_instance *inst)
	{
	crypto_drop_spawn(crypto_instance_ctx(inst));
	kfree(inst);
	}

	static struct crypto_template crypto_cbc_tmpl = {
	.name = "cbc",
	.alloc = crypto_cbc_alloc,
	.free = crypto_cbc_free,
	.module = THIS_MODULE,
	};

	static int __init crypto_cbc_module_init(void)
	{
	return crypto_register_template(&crypto_cbc_tmpl);
	}

	static void __exit crypto_cbc_module_exit(void)
	{
	crypto_unregister_template(&crypto_cbc_tmpl);
	}

	module_init(crypto_cbc_module_init);
	module_exit(crypto_cbc_module_exit);

	MODULE_LICENSE("GPL");
	MODULE_DESCRIPTION("CBC block cipher algorithm");