[mirror_ubuntu-artful-kernel.git] / crypto / pcbc.c

/*
 * PCBC: Propagating Cipher Block Chaining mode
 *
 * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * Derived from cbc.c
 * - 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/internal/skcipher.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>

struct crypto_pcbc_ctx {
	struct crypto_cipher *child;
};

static int crypto_pcbc_setkey(struct crypto_skcipher *parent, const u8 *key,
			      unsigned int keylen)
{
	struct crypto_pcbc_ctx *ctx = crypto_skcipher_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_skcipher_get_flags(parent) &
				       CRYPTO_TFM_REQ_MASK);
	err = crypto_cipher_setkey(child, key, keylen);
	crypto_skcipher_set_flags(parent, crypto_cipher_get_flags(child) &
					  CRYPTO_TFM_RES_MASK);
	return err;
}

static int crypto_pcbc_encrypt_segment(struct skcipher_request *req,
				       struct skcipher_walk *walk,
				       struct crypto_cipher *tfm)
{
	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 {
		crypto_xor(iv, src, bsize);
		crypto_cipher_encrypt_one(tfm, dst, iv);
		memcpy(iv, dst, bsize);
		crypto_xor(iv, src, bsize);

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

	return nbytes;
}

static int crypto_pcbc_encrypt_inplace(struct skcipher_request *req,
				       struct skcipher_walk *walk,
				       struct crypto_cipher *tfm)
{
	int bsize = crypto_cipher_blocksize(tfm);
	unsigned int nbytes = walk->nbytes;
	u8 *src = walk->src.virt.addr;
	u8 *iv = walk->iv;
	u8 tmpbuf[bsize];

	do {
		memcpy(tmpbuf, src, bsize);
		crypto_xor(iv, src, bsize);
		crypto_cipher_encrypt_one(tfm, src, iv);
		memcpy(iv, tmpbuf, bsize);
		crypto_xor(iv, src, bsize);

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

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

	return nbytes;
}

static int crypto_pcbc_encrypt(struct skcipher_request *req)
{
	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
	struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(tfm);
	struct crypto_cipher *child = ctx->child;
	struct skcipher_walk walk;
	unsigned int nbytes;
	int err;

	err = skcipher_walk_virt(&walk, req, false);

	while ((nbytes = walk.nbytes)) {
		if (walk.src.virt.addr == walk.dst.virt.addr)
			nbytes = crypto_pcbc_encrypt_inplace(req, &walk,
							     child);
		else
			nbytes = crypto_pcbc_encrypt_segment(req, &walk,
							     child);
		err = skcipher_walk_done(&walk, nbytes);
	}

	return err;
}

static int crypto_pcbc_decrypt_segment(struct skcipher_request *req,
				       struct skcipher_walk *walk,
				       struct crypto_cipher *tfm)
{
	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 {
		crypto_cipher_decrypt_one(tfm, dst, src);
		crypto_xor(dst, iv, bsize);
		memcpy(iv, src, bsize);
		crypto_xor(iv, dst, bsize);

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

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

	return nbytes;
}

static int crypto_pcbc_decrypt_inplace(struct skcipher_request *req,
				       struct skcipher_walk *walk,
				       struct crypto_cipher *tfm)
{
	int bsize = crypto_cipher_blocksize(tfm);
	unsigned int nbytes = walk->nbytes;
	u8 *src = walk->src.virt.addr;
	u8 *iv = walk->iv;
	u8 tmpbuf[bsize] __attribute__ ((aligned(__alignof__(u32))));

	do {
		memcpy(tmpbuf, src, bsize);
		crypto_cipher_decrypt_one(tfm, src, src);
		crypto_xor(src, iv, bsize);
		memcpy(iv, tmpbuf, bsize);
		crypto_xor(iv, src, bsize);

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

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

	return nbytes;
}

static int crypto_pcbc_decrypt(struct skcipher_request *req)
{
	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
	struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(tfm);
	struct crypto_cipher *child = ctx->child;
	struct skcipher_walk walk;
	unsigned int nbytes;
	int err;

	err = skcipher_walk_virt(&walk, req, false);

	while ((nbytes = walk.nbytes)) {
		if (walk.src.virt.addr == walk.dst.virt.addr)
			nbytes = crypto_pcbc_decrypt_inplace(req, &walk,
							     child);
		else
			nbytes = crypto_pcbc_decrypt_segment(req, &walk,
							     child);
		err = skcipher_walk_done(&walk, nbytes);
	}

	return err;
}

static int crypto_pcbc_init_tfm(struct crypto_skcipher *tfm)
{
	struct skcipher_instance *inst = skcipher_alg_instance(tfm);
	struct crypto_spawn *spawn = skcipher_instance_ctx(inst);
	struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(tfm);
	struct crypto_cipher *cipher;

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

	ctx->child = cipher;
	return 0;
}

static void crypto_pcbc_exit_tfm(struct crypto_skcipher *tfm)
{
	struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(tfm);

	crypto_free_cipher(ctx->child);
}

static void crypto_pcbc_free(struct skcipher_instance *inst)
{
	crypto_drop_skcipher(skcipher_instance_ctx(inst));
	kfree(inst);
}

static int crypto_pcbc_create(struct crypto_template *tmpl, struct rtattr **tb)
{
	struct skcipher_instance *inst;
	struct crypto_attr_type *algt;
	struct crypto_spawn *spawn;
	struct crypto_alg *alg;
	int err;

	algt = crypto_get_attr_type(tb);
	if (IS_ERR(algt))
		return PTR_ERR(algt);

	if (((algt->type ^ CRYPTO_ALG_TYPE_SKCIPHER) & algt->mask) &
	    ~CRYPTO_ALG_INTERNAL)
		return -EINVAL;

	inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
	if (!inst)
		return -ENOMEM;

	alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER |
				      (algt->type & CRYPTO_ALG_INTERNAL),
				  CRYPTO_ALG_TYPE_MASK |
				  (algt->mask & CRYPTO_ALG_INTERNAL));
	err = PTR_ERR(alg);
	if (IS_ERR(alg))
		goto err_free_inst;

	spawn = skcipher_instance_ctx(inst);
	err = crypto_init_spawn(spawn, alg, skcipher_crypto_instance(inst),
				CRYPTO_ALG_TYPE_MASK);
	crypto_mod_put(alg);
	if (err)
		goto err_free_inst;

	err = crypto_inst_setname(skcipher_crypto_instance(inst), "pcbc", alg);
	if (err)
		goto err_drop_spawn;

	inst->alg.base.cra_flags = alg->cra_flags & CRYPTO_ALG_INTERNAL;
	inst->alg.base.cra_priority = alg->cra_priority;
	inst->alg.base.cra_blocksize = alg->cra_blocksize;
	inst->alg.base.cra_alignmask = alg->cra_alignmask;

	/* We access the data as u32s when xoring. */
	inst->alg.base.cra_alignmask |= __alignof__(u32) - 1;

	inst->alg.ivsize = alg->cra_blocksize;
	inst->alg.min_keysize = alg->cra_cipher.cia_min_keysize;
	inst->alg.max_keysize = alg->cra_cipher.cia_max_keysize;

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

	inst->alg.init = crypto_pcbc_init_tfm;
	inst->alg.exit = crypto_pcbc_exit_tfm;

	inst->alg.setkey = crypto_pcbc_setkey;
	inst->alg.encrypt = crypto_pcbc_encrypt;
	inst->alg.decrypt = crypto_pcbc_decrypt;

	inst->free = crypto_pcbc_free;

	err = skcipher_register_instance(tmpl, inst);
	if (err)
		goto err_drop_spawn;

out:
	return err;

err_drop_spawn:
	crypto_drop_spawn(spawn);
err_free_inst:
	kfree(inst);
	goto out;
}

static struct crypto_template crypto_pcbc_tmpl = {
	.name = "pcbc",
	.create = crypto_pcbc_create,
	.module = THIS_MODULE,
};

static int __init crypto_pcbc_module_init(void)
{
	return crypto_register_template(&crypto_pcbc_tmpl);
}

static void __exit crypto_pcbc_module_exit(void)
{
	crypto_unregister_template(&crypto_pcbc_tmpl);
}

module_init(crypto_pcbc_module_init);
module_exit(crypto_pcbc_module_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("PCBC block cipher algorithm");
MODULE_ALIAS_CRYPTO("pcbc");
Commit	Line	Data
91652be5 DH	1	/*
	2	* PCBC: Propagating Cipher Block Chaining mode
	3	*
	4	* Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
	5	* Written by David Howells (dhowells@redhat.com)
	6	*
	7	* Derived from cbc.c
	8	* - Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
	9	*
	10	* This program is free software; you can redistribute it and/or modify it
	11	* under the terms of the GNU General Public License as published by the Free
	12	* Software Foundation; either version 2 of the License, or (at your option)
	13	* any later version.
	14	*
	15	*/
	16
043a4400	17	#include <crypto/internal/skcipher.h>
91652be5 DH	18	#include <linux/err.h>
	19	#include <linux/init.h>
	20	#include <linux/kernel.h>
	21	#include <linux/module.h>
91652be5 DH	22	#include <linux/slab.h>
	23
	24	struct crypto_pcbc_ctx {
	25	struct crypto_cipher *child;
91652be5 DH	26	};
91652be5 DH	27
043a4400	28	static int crypto_pcbc_setkey(struct crypto_skcipher parent, const u8 key,
91652be5 DH	29	unsigned int keylen)
91652be5 DH	30	{
043a4400	31	struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(parent);
91652be5 DH	32	struct crypto_cipher *child = ctx->child;
	33	int err;
	34
	35	crypto_cipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
043a4400 HX	36	crypto_cipher_set_flags(child, crypto_skcipher_get_flags(parent) &
043a4400 HX	37	CRYPTO_TFM_REQ_MASK);
91652be5	38	err = crypto_cipher_setkey(child, key, keylen);
043a4400 HX	39	crypto_skcipher_set_flags(parent, crypto_cipher_get_flags(child) &
043a4400 HX	40	CRYPTO_TFM_RES_MASK);
91652be5 DH	41	return err;
	42	}
	43
043a4400 HX	44	static int crypto_pcbc_encrypt_segment(struct skcipher_request *req,
043a4400 HX	45	struct skcipher_walk *walk,
d0b9007a	46	struct crypto_cipher *tfm)
91652be5	47	{
91652be5 DH	48	int bsize = crypto_cipher_blocksize(tfm);
	49	unsigned int nbytes = walk->nbytes;
	50	u8 *src = walk->src.virt.addr;
	51	u8 *dst = walk->dst.virt.addr;
	52	u8 *iv = walk->iv;
	53
	54	do {
d0b9007a	55	crypto_xor(iv, src, bsize);
043a4400	56	crypto_cipher_encrypt_one(tfm, dst, iv);
91652be5	57	memcpy(iv, dst, bsize);
d0b9007a	58	crypto_xor(iv, src, bsize);
91652be5 DH	59
	60	src += bsize;
	61	dst += bsize;
	62	} while ((nbytes -= bsize) >= bsize);
	63
	64	return nbytes;
	65	}
	66
043a4400 HX	67	static int crypto_pcbc_encrypt_inplace(struct skcipher_request *req,
043a4400 HX	68	struct skcipher_walk *walk,
d0b9007a	69	struct crypto_cipher *tfm)
91652be5	70	{
91652be5 DH	71	int bsize = crypto_cipher_blocksize(tfm);
	72	unsigned int nbytes = walk->nbytes;
	73	u8 *src = walk->src.virt.addr;
	74	u8 *iv = walk->iv;
	75	u8 tmpbuf[bsize];
	76
	77	do {
	78	memcpy(tmpbuf, src, bsize);
d0b9007a	79	crypto_xor(iv, src, bsize);
043a4400	80	crypto_cipher_encrypt_one(tfm, src, iv);
d0b9007a HX	81	memcpy(iv, tmpbuf, bsize);
d0b9007a HX	82	crypto_xor(iv, src, bsize);
91652be5 DH	83
	84	src += bsize;
	85	} while ((nbytes -= bsize) >= bsize);
	86
	87	memcpy(walk->iv, iv, bsize);
	88
	89	return nbytes;
	90	}
	91
043a4400	92	static int crypto_pcbc_encrypt(struct skcipher_request *req)
91652be5	93	{
043a4400 HX	94	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
043a4400 HX	95	struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(tfm);
91652be5	96	struct crypto_cipher *child = ctx->child;
043a4400 HX	97	struct skcipher_walk walk;
043a4400 HX	98	unsigned int nbytes;
91652be5 DH	99	int err;
91652be5 DH	100
043a4400	101	err = skcipher_walk_virt(&walk, req, false);
91652be5 DH	102
	103	while ((nbytes = walk.nbytes)) {
	104	if (walk.src.virt.addr == walk.dst.virt.addr)
043a4400	105	nbytes = crypto_pcbc_encrypt_inplace(req, &walk,
d0b9007a	106	child);
91652be5	107	else
043a4400	108	nbytes = crypto_pcbc_encrypt_segment(req, &walk,
d0b9007a	109	child);
043a4400	110	err = skcipher_walk_done(&walk, nbytes);
91652be5 DH	111	}
	112
	113	return err;
	114	}
	115
043a4400 HX	116	static int crypto_pcbc_decrypt_segment(struct skcipher_request *req,
043a4400 HX	117	struct skcipher_walk *walk,
d0b9007a	118	struct crypto_cipher *tfm)
91652be5	119	{
91652be5 DH	120	int bsize = crypto_cipher_blocksize(tfm);
	121	unsigned int nbytes = walk->nbytes;
	122	u8 *src = walk->src.virt.addr;
	123	u8 *dst = walk->dst.virt.addr;
	124	u8 *iv = walk->iv;
	125
	126	do {
043a4400	127	crypto_cipher_decrypt_one(tfm, dst, src);
d0b9007a	128	crypto_xor(dst, iv, bsize);
91652be5	129	memcpy(iv, src, bsize);
d0b9007a	130	crypto_xor(iv, dst, bsize);
91652be5 DH	131
	132	src += bsize;
	133	dst += bsize;
	134	} while ((nbytes -= bsize) >= bsize);
	135
	136	memcpy(walk->iv, iv, bsize);
	137
	138	return nbytes;
	139	}
	140
043a4400 HX	141	static int crypto_pcbc_decrypt_inplace(struct skcipher_request *req,
043a4400 HX	142	struct skcipher_walk *walk,
d0b9007a	143	struct crypto_cipher *tfm)
91652be5	144	{
91652be5 DH	145	int bsize = crypto_cipher_blocksize(tfm);
	146	unsigned int nbytes = walk->nbytes;
	147	u8 *src = walk->src.virt.addr;
	148	u8 *iv = walk->iv;
043a4400	149	u8 tmpbuf[bsize] __attribute__ ((aligned(__alignof__(u32))));
91652be5 DH	150
	151	do {
	152	memcpy(tmpbuf, src, bsize);
043a4400	153	crypto_cipher_decrypt_one(tfm, src, src);
d0b9007a	154	crypto_xor(src, iv, bsize);
91652be5	155	memcpy(iv, tmpbuf, bsize);
d0b9007a	156	crypto_xor(iv, src, bsize);
91652be5 DH	157
	158	src += bsize;
	159	} while ((nbytes -= bsize) >= bsize);
	160
	161	memcpy(walk->iv, iv, bsize);
	162
	163	return nbytes;
	164	}
	165
043a4400	166	static int crypto_pcbc_decrypt(struct skcipher_request *req)
91652be5	167	{
043a4400 HX	168	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
043a4400 HX	169	struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(tfm);
91652be5	170	struct crypto_cipher *child = ctx->child;
043a4400 HX	171	struct skcipher_walk walk;
043a4400 HX	172	unsigned int nbytes;
91652be5 DH	173	int err;
91652be5 DH	174
043a4400	175	err = skcipher_walk_virt(&walk, req, false);
91652be5 DH	176
	177	while ((nbytes = walk.nbytes)) {
	178	if (walk.src.virt.addr == walk.dst.virt.addr)
043a4400	179	nbytes = crypto_pcbc_decrypt_inplace(req, &walk,
d0b9007a	180	child);
91652be5	181	else
043a4400	182	nbytes = crypto_pcbc_decrypt_segment(req, &walk,
d0b9007a	183	child);
043a4400	184	err = skcipher_walk_done(&walk, nbytes);
91652be5 DH	185	}
	186
	187	return err;
	188	}
	189
043a4400	190	static int crypto_pcbc_init_tfm(struct crypto_skcipher *tfm)
91652be5	191	{
043a4400 HX	192	struct skcipher_instance *inst = skcipher_alg_instance(tfm);
	193	struct crypto_spawn *spawn = skcipher_instance_ctx(inst);
	194	struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(tfm);
2e306ee0	195	struct crypto_cipher *cipher;
91652be5	196
2e306ee0 HX	197	cipher = crypto_spawn_cipher(spawn);
	198	if (IS_ERR(cipher))
	199	return PTR_ERR(cipher);
91652be5	200
2e306ee0	201	ctx->child = cipher;
91652be5 DH	202	return 0;
	203	}
	204
043a4400	205	static void crypto_pcbc_exit_tfm(struct crypto_skcipher *tfm)
91652be5	206	{
043a4400 HX	207	struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(tfm);
043a4400 HX	208
91652be5 DH	209	crypto_free_cipher(ctx->child);
	210	}
	211
043a4400 HX	212	static void crypto_pcbc_free(struct skcipher_instance *inst)
	213	{
	214	crypto_drop_skcipher(skcipher_instance_ctx(inst));
	215	kfree(inst);
	216	}
	217
	218	static int crypto_pcbc_create(struct crypto_template tmpl, struct rtattr *tb)
91652be5	219	{
043a4400 HX	220	struct skcipher_instance *inst;
	221	struct crypto_attr_type *algt;
	222	struct crypto_spawn *spawn;
91652be5	223	struct crypto_alg *alg;
ebc610e5 HX	224	int err;
ebc610e5 HX	225
043a4400 HX	226	algt = crypto_get_attr_type(tb);
	227	if (IS_ERR(algt))
	228	return PTR_ERR(algt);
	229
	230	if (((algt->type ^ CRYPTO_ALG_TYPE_SKCIPHER) & algt->mask) &
	231	~CRYPTO_ALG_INTERNAL)
	232	return -EINVAL;
91652be5	233
043a4400 HX	234	inst = kzalloc(sizeof(inst) + sizeof(spawn), GFP_KERNEL);
	235	if (!inst)
	236	return -ENOMEM;
	237
	238	alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER \|
	239	(algt->type & CRYPTO_ALG_INTERNAL),
	240	CRYPTO_ALG_TYPE_MASK \|
	241	(algt->mask & CRYPTO_ALG_INTERNAL));
	242	err = PTR_ERR(alg);
91652be5	243	if (IS_ERR(alg))
043a4400 HX	244	goto err_free_inst;
	245
	246	spawn = skcipher_instance_ctx(inst);
	247	err = crypto_init_spawn(spawn, alg, skcipher_crypto_instance(inst),
	248	CRYPTO_ALG_TYPE_MASK);
	249	crypto_mod_put(alg);
	250	if (err)
	251	goto err_free_inst;
91652be5	252
043a4400 HX	253	err = crypto_inst_setname(skcipher_crypto_instance(inst), "pcbc", alg);
	254	if (err)
	255	goto err_drop_spawn;
91652be5	256
043a4400 HX	257	inst->alg.base.cra_flags = alg->cra_flags & CRYPTO_ALG_INTERNAL;
	258	inst->alg.base.cra_priority = alg->cra_priority;
	259	inst->alg.base.cra_blocksize = alg->cra_blocksize;
	260	inst->alg.base.cra_alignmask = alg->cra_alignmask;
91652be5	261
d0b9007a	262	/* We access the data as u32s when xoring. */
043a4400	263	inst->alg.base.cra_alignmask \|= __alignof__(u32) - 1;
d0b9007a	264
043a4400 HX	265	inst->alg.ivsize = alg->cra_blocksize;
	266	inst->alg.min_keysize = alg->cra_cipher.cia_min_keysize;
	267	inst->alg.max_keysize = alg->cra_cipher.cia_max_keysize;
91652be5	268
043a4400	269	inst->alg.base.cra_ctxsize = sizeof(struct crypto_pcbc_ctx);
91652be5	270
043a4400 HX	271	inst->alg.init = crypto_pcbc_init_tfm;
043a4400 HX	272	inst->alg.exit = crypto_pcbc_exit_tfm;
91652be5	273
043a4400 HX	274	inst->alg.setkey = crypto_pcbc_setkey;
	275	inst->alg.encrypt = crypto_pcbc_encrypt;
	276	inst->alg.decrypt = crypto_pcbc_decrypt;
91652be5	277
043a4400	278	inst->free = crypto_pcbc_free;
91652be5	279
043a4400 HX	280	err = skcipher_register_instance(tmpl, inst);
	281	if (err)
	282	goto err_drop_spawn;
	283
	284	out:
	285	return err;
	286
	287	err_drop_spawn:
	288	crypto_drop_spawn(spawn);
	289	err_free_inst:
91652be5	290	kfree(inst);
043a4400	291	goto out;
91652be5 DH	292	}
	293
	294	static struct crypto_template crypto_pcbc_tmpl = {
	295	.name = "pcbc",
043a4400	296	.create = crypto_pcbc_create,
91652be5 DH	297	.module = THIS_MODULE,
	298	};
	299
	300	static int __init crypto_pcbc_module_init(void)
	301	{
	302	return crypto_register_template(&crypto_pcbc_tmpl);
	303	}
	304
	305	static void __exit crypto_pcbc_module_exit(void)
	306	{
	307	crypto_unregister_template(&crypto_pcbc_tmpl);
	308	}
	309
	310	module_init(crypto_pcbc_module_init);
	311	module_exit(crypto_pcbc_module_exit);
	312
	313	MODULE_LICENSE("GPL");
	314	MODULE_DESCRIPTION("PCBC block cipher algorithm");
4943ba16	315	MODULE_ALIAS_CRYPTO("pcbc");