[linux-2.6-block.git] / crypto / skcipher.c

/*
 * Symmetric key cipher operations.
 *
 * Generic encrypt/decrypt wrapper for ciphers, handles operations across
 * multiple page boundaries by using temporary blocks.  In user context,
 * the kernel is given a chance to schedule us once per page.
 *
 * Copyright (c) 2015 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/bug.h>
#include <linux/module.h>

#include "internal.h"

static unsigned int crypto_skcipher_extsize(struct crypto_alg *alg)
{
	if (alg->cra_type == &crypto_blkcipher_type)
		return sizeof(struct crypto_blkcipher *);

	BUG_ON(alg->cra_type != &crypto_ablkcipher_type &&
	       alg->cra_type != &crypto_givcipher_type);

	return sizeof(struct crypto_ablkcipher *);
}

static int skcipher_setkey_blkcipher(struct crypto_skcipher *tfm,
				     const u8 *key, unsigned int keylen)
{
	struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm);
	struct crypto_blkcipher *blkcipher = *ctx;
	int err;

	crypto_blkcipher_clear_flags(blkcipher, ~0);
	crypto_blkcipher_set_flags(blkcipher, crypto_skcipher_get_flags(tfm) &
					      CRYPTO_TFM_REQ_MASK);
	err = crypto_blkcipher_setkey(blkcipher, key, keylen);
	crypto_skcipher_set_flags(tfm, crypto_blkcipher_get_flags(blkcipher) &
				       CRYPTO_TFM_RES_MASK);

	return err;
}

static int skcipher_crypt_blkcipher(struct skcipher_request *req,
				    int (*crypt)(struct blkcipher_desc *,
						 struct scatterlist *,
						 struct scatterlist *,
						 unsigned int))
{
	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
	struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm);
	struct blkcipher_desc desc = {
		.tfm = *ctx,
		.info = req->iv,
		.flags = req->base.flags,
	};


	return crypt(&desc, req->dst, req->src, req->cryptlen);
}

static int skcipher_encrypt_blkcipher(struct skcipher_request *req)
{
	struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
	struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;

	return skcipher_crypt_blkcipher(req, alg->encrypt);
}

static int skcipher_decrypt_blkcipher(struct skcipher_request *req)
{
	struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
	struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;

	return skcipher_crypt_blkcipher(req, alg->decrypt);
}

static void crypto_exit_skcipher_ops_blkcipher(struct crypto_tfm *tfm)
{
	struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm);

	crypto_free_blkcipher(*ctx);
}

static int crypto_init_skcipher_ops_blkcipher(struct crypto_tfm *tfm)
{
	struct crypto_alg *calg = tfm->__crt_alg;
	struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
	struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm);
	struct crypto_blkcipher *blkcipher;
	struct crypto_tfm *btfm;

	if (!crypto_mod_get(calg))
		return -EAGAIN;

	btfm = __crypto_alloc_tfm(calg, CRYPTO_ALG_TYPE_BLKCIPHER,
					CRYPTO_ALG_TYPE_MASK);
	if (IS_ERR(btfm)) {
		crypto_mod_put(calg);
		return PTR_ERR(btfm);
	}

	blkcipher = __crypto_blkcipher_cast(btfm);
	*ctx = blkcipher;
	tfm->exit = crypto_exit_skcipher_ops_blkcipher;

	skcipher->setkey = skcipher_setkey_blkcipher;
	skcipher->encrypt = skcipher_encrypt_blkcipher;
	skcipher->decrypt = skcipher_decrypt_blkcipher;

	skcipher->ivsize = crypto_blkcipher_ivsize(blkcipher);
	skcipher->keysize = calg->cra_blkcipher.max_keysize;

	return 0;
}

static int skcipher_setkey_ablkcipher(struct crypto_skcipher *tfm,
				      const u8 *key, unsigned int keylen)
{
	struct crypto_ablkcipher **ctx = crypto_skcipher_ctx(tfm);
	struct crypto_ablkcipher *ablkcipher = *ctx;
	int err;

	crypto_ablkcipher_clear_flags(ablkcipher, ~0);
	crypto_ablkcipher_set_flags(ablkcipher,
				    crypto_skcipher_get_flags(tfm) &
				    CRYPTO_TFM_REQ_MASK);
	err = crypto_ablkcipher_setkey(ablkcipher, key, keylen);
	crypto_skcipher_set_flags(tfm,
				  crypto_ablkcipher_get_flags(ablkcipher) &
				  CRYPTO_TFM_RES_MASK);

	return err;
}

static int skcipher_crypt_ablkcipher(struct skcipher_request *req,
				     int (*crypt)(struct ablkcipher_request *))
{
	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
	struct crypto_ablkcipher **ctx = crypto_skcipher_ctx(tfm);
	struct ablkcipher_request *subreq = skcipher_request_ctx(req);

	ablkcipher_request_set_tfm(subreq, *ctx);
	ablkcipher_request_set_callback(subreq, skcipher_request_flags(req),
					req->base.complete, req->base.data);
	ablkcipher_request_set_crypt(subreq, req->src, req->dst, req->cryptlen,
				     req->iv);

	return crypt(subreq);
}

static int skcipher_encrypt_ablkcipher(struct skcipher_request *req)
{
	struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
	struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;

	return skcipher_crypt_ablkcipher(req, alg->encrypt);
}

static int skcipher_decrypt_ablkcipher(struct skcipher_request *req)
{
	struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
	struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;

	return skcipher_crypt_ablkcipher(req, alg->decrypt);
}

static void crypto_exit_skcipher_ops_ablkcipher(struct crypto_tfm *tfm)
{
	struct crypto_ablkcipher **ctx = crypto_tfm_ctx(tfm);

	crypto_free_ablkcipher(*ctx);
}

static int crypto_init_skcipher_ops_ablkcipher(struct crypto_tfm *tfm)
{
	struct crypto_alg *calg = tfm->__crt_alg;
	struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
	struct crypto_ablkcipher **ctx = crypto_tfm_ctx(tfm);
	struct crypto_ablkcipher *ablkcipher;
	struct crypto_tfm *abtfm;

	if (!crypto_mod_get(calg))
		return -EAGAIN;

	abtfm = __crypto_alloc_tfm(calg, 0, 0);
	if (IS_ERR(abtfm)) {
		crypto_mod_put(calg);
		return PTR_ERR(abtfm);
	}

	ablkcipher = __crypto_ablkcipher_cast(abtfm);
	*ctx = ablkcipher;
	tfm->exit = crypto_exit_skcipher_ops_ablkcipher;

	skcipher->setkey = skcipher_setkey_ablkcipher;
	skcipher->encrypt = skcipher_encrypt_ablkcipher;
	skcipher->decrypt = skcipher_decrypt_ablkcipher;

	skcipher->ivsize = crypto_ablkcipher_ivsize(ablkcipher);
	skcipher->reqsize = crypto_ablkcipher_reqsize(ablkcipher) +
			    sizeof(struct ablkcipher_request);
	skcipher->keysize = calg->cra_ablkcipher.max_keysize;

	return 0;
}

static int crypto_skcipher_init_tfm(struct crypto_tfm *tfm)
{
	if (tfm->__crt_alg->cra_type == &crypto_blkcipher_type)
		return crypto_init_skcipher_ops_blkcipher(tfm);

	BUG_ON(tfm->__crt_alg->cra_type != &crypto_ablkcipher_type &&
	       tfm->__crt_alg->cra_type != &crypto_givcipher_type);

	return crypto_init_skcipher_ops_ablkcipher(tfm);
}

static const struct crypto_type crypto_skcipher_type2 = {
	.extsize = crypto_skcipher_extsize,
	.init_tfm = crypto_skcipher_init_tfm,
	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
	.maskset = CRYPTO_ALG_TYPE_BLKCIPHER_MASK,
	.type = CRYPTO_ALG_TYPE_BLKCIPHER,
	.tfmsize = offsetof(struct crypto_skcipher, base),
};

struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name,
					      u32 type, u32 mask)
{
	return crypto_alloc_tfm(alg_name, &crypto_skcipher_type2, type, mask);
}
EXPORT_SYMBOL_GPL(crypto_alloc_skcipher);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Symmetric key cipher type");
Commit	Line	Data
7a7ffe65 HX	1	/*
	2	* Symmetric key cipher operations.
	3	*
	4	* Generic encrypt/decrypt wrapper for ciphers, handles operations across
	5	* multiple page boundaries by using temporary blocks. In user context,
	6	* the kernel is given a chance to schedule us once per page.
	7	*
	8	* Copyright (c) 2015 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
	17	#include <crypto/internal/skcipher.h>
	18	#include <linux/bug.h>
	19	#include <linux/module.h>
	20
	21	#include "internal.h"
	22
	23	static unsigned int crypto_skcipher_extsize(struct crypto_alg *alg)
	24	{
	25	if (alg->cra_type == &crypto_blkcipher_type)
	26	return sizeof(struct crypto_blkcipher *);
	27
	28	BUG_ON(alg->cra_type != &crypto_ablkcipher_type &&
	29	alg->cra_type != &crypto_givcipher_type);
	30
	31	return sizeof(struct crypto_ablkcipher *);
	32	}
	33
	34	static int skcipher_setkey_blkcipher(struct crypto_skcipher *tfm,
	35	const u8 *key, unsigned int keylen)
	36	{
	37	struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm);
	38	struct crypto_blkcipher blkcipher = ctx;
	39	int err;
	40
	41	crypto_blkcipher_clear_flags(blkcipher, ~0);
	42	crypto_blkcipher_set_flags(blkcipher, crypto_skcipher_get_flags(tfm) &
	43	CRYPTO_TFM_REQ_MASK);
	44	err = crypto_blkcipher_setkey(blkcipher, key, keylen);
	45	crypto_skcipher_set_flags(tfm, crypto_blkcipher_get_flags(blkcipher) &
	46	CRYPTO_TFM_RES_MASK);
	47
	48	return err;
	49	}
	50
	51	static int skcipher_crypt_blkcipher(struct skcipher_request *req,
	52	int (crypt)(struct blkcipher_desc ,
	53	struct scatterlist *,
	54	struct scatterlist *,
	55	unsigned int))
	56	{
	57	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
	58	struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm);
	59	struct blkcipher_desc desc = {
	60	.tfm = *ctx,
	61	.info = req->iv,
	62	.flags = req->base.flags,
	63	};
	64
65
66	return crypt(&desc, req->dst, req->src, req->cryptlen);
67	}
68
69	static int skcipher_encrypt_blkcipher(struct skcipher_request *req)
70	{
71	struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
72	struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
73	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
74
75	return skcipher_crypt_blkcipher(req, alg->encrypt);
76	}
77
78	static int skcipher_decrypt_blkcipher(struct skcipher_request *req)
79	{
80	struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
81	struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
82	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
83
84	return skcipher_crypt_blkcipher(req, alg->decrypt);
85	}
86
87	static void crypto_exit_skcipher_ops_blkcipher(struct crypto_tfm *tfm)
88	{
89	struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm);
90
91	crypto_free_blkcipher(*ctx);
92	}
93
ecdd6bed	94	static int crypto_init_skcipher_ops_blkcipher(struct crypto_tfm *tfm)
7a7ffe65 HX	95	{
	96	struct crypto_alg *calg = tfm->__crt_alg;
	97	struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
	98	struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm);
	99	struct crypto_blkcipher *blkcipher;
	100	struct crypto_tfm *btfm;
	101
	102	if (!crypto_mod_get(calg))
	103	return -EAGAIN;
	104
	105	btfm = __crypto_alloc_tfm(calg, CRYPTO_ALG_TYPE_BLKCIPHER,
	106	CRYPTO_ALG_TYPE_MASK);
	107	if (IS_ERR(btfm)) {
	108	crypto_mod_put(calg);
	109	return PTR_ERR(btfm);
	110	}
	111
	112	blkcipher = __crypto_blkcipher_cast(btfm);
	113	*ctx = blkcipher;
	114	tfm->exit = crypto_exit_skcipher_ops_blkcipher;
	115
	116	skcipher->setkey = skcipher_setkey_blkcipher;
	117	skcipher->encrypt = skcipher_encrypt_blkcipher;
	118	skcipher->decrypt = skcipher_decrypt_blkcipher;
	119
	120	skcipher->ivsize = crypto_blkcipher_ivsize(blkcipher);
973fb3fb	121	skcipher->keysize = calg->cra_blkcipher.max_keysize;
7a7ffe65 HX	122
	123	return 0;
	124	}
	125
	126	static int skcipher_setkey_ablkcipher(struct crypto_skcipher *tfm,
	127	const u8 *key, unsigned int keylen)
	128	{
	129	struct crypto_ablkcipher **ctx = crypto_skcipher_ctx(tfm);
	130	struct crypto_ablkcipher ablkcipher = ctx;
	131	int err;
	132
	133	crypto_ablkcipher_clear_flags(ablkcipher, ~0);
	134	crypto_ablkcipher_set_flags(ablkcipher,
	135	crypto_skcipher_get_flags(tfm) &
	136	CRYPTO_TFM_REQ_MASK);
	137	err = crypto_ablkcipher_setkey(ablkcipher, key, keylen);
	138	crypto_skcipher_set_flags(tfm,
	139	crypto_ablkcipher_get_flags(ablkcipher) &
	140	CRYPTO_TFM_RES_MASK);
	141
	142	return err;
	143	}
	144
	145	static int skcipher_crypt_ablkcipher(struct skcipher_request *req,
	146	int (crypt)(struct ablkcipher_request ))
	147	{
	148	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
	149	struct crypto_ablkcipher **ctx = crypto_skcipher_ctx(tfm);
	150	struct ablkcipher_request *subreq = skcipher_request_ctx(req);
	151
	152	ablkcipher_request_set_tfm(subreq, *ctx);
	153	ablkcipher_request_set_callback(subreq, skcipher_request_flags(req),
	154	req->base.complete, req->base.data);
	155	ablkcipher_request_set_crypt(subreq, req->src, req->dst, req->cryptlen,
	156	req->iv);
	157
	158	return crypt(subreq);
	159	}
	160
	161	static int skcipher_encrypt_ablkcipher(struct skcipher_request *req)
	162	{
	163	struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
	164	struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
	165	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
	166
	167	return skcipher_crypt_ablkcipher(req, alg->encrypt);
	168	}
	169
	170	static int skcipher_decrypt_ablkcipher(struct skcipher_request *req)
	171	{
	172	struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
	173	struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
	174	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
	175
	176	return skcipher_crypt_ablkcipher(req, alg->decrypt);
	177	}
	178
	179	static void crypto_exit_skcipher_ops_ablkcipher(struct crypto_tfm *tfm)
	180	{
	181	struct crypto_ablkcipher **ctx = crypto_tfm_ctx(tfm);
	182
	183	crypto_free_ablkcipher(*ctx);
	184	}
	185
ecdd6bed	186	static int crypto_init_skcipher_ops_ablkcipher(struct crypto_tfm *tfm)
7a7ffe65 HX	187	{
	188	struct crypto_alg *calg = tfm->__crt_alg;
	189	struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
	190	struct crypto_ablkcipher **ctx = crypto_tfm_ctx(tfm);
	191	struct crypto_ablkcipher *ablkcipher;
	192	struct crypto_tfm *abtfm;
	193
	194	if (!crypto_mod_get(calg))
	195	return -EAGAIN;
	196
	197	abtfm = __crypto_alloc_tfm(calg, 0, 0);
	198	if (IS_ERR(abtfm)) {
	199	crypto_mod_put(calg);
	200	return PTR_ERR(abtfm);
	201	}
	202
	203	ablkcipher = __crypto_ablkcipher_cast(abtfm);
	204	*ctx = ablkcipher;
	205	tfm->exit = crypto_exit_skcipher_ops_ablkcipher;
	206
	207	skcipher->setkey = skcipher_setkey_ablkcipher;
	208	skcipher->encrypt = skcipher_encrypt_ablkcipher;
	209	skcipher->decrypt = skcipher_decrypt_ablkcipher;
	210
	211	skcipher->ivsize = crypto_ablkcipher_ivsize(ablkcipher);
	212	skcipher->reqsize = crypto_ablkcipher_reqsize(ablkcipher) +
	213	sizeof(struct ablkcipher_request);
973fb3fb	214	skcipher->keysize = calg->cra_ablkcipher.max_keysize;
7a7ffe65 HX	215
	216	return 0;
	217	}
	218
	219	static int crypto_skcipher_init_tfm(struct crypto_tfm *tfm)
	220	{
	221	if (tfm->__crt_alg->cra_type == &crypto_blkcipher_type)
	222	return crypto_init_skcipher_ops_blkcipher(tfm);
	223
	224	BUG_ON(tfm->__crt_alg->cra_type != &crypto_ablkcipher_type &&
	225	tfm->__crt_alg->cra_type != &crypto_givcipher_type);
	226
	227	return crypto_init_skcipher_ops_ablkcipher(tfm);
	228	}
	229
	230	static const struct crypto_type crypto_skcipher_type2 = {
	231	.extsize = crypto_skcipher_extsize,
	232	.init_tfm = crypto_skcipher_init_tfm,
	233	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
	234	.maskset = CRYPTO_ALG_TYPE_BLKCIPHER_MASK,
	235	.type = CRYPTO_ALG_TYPE_BLKCIPHER,
	236	.tfmsize = offsetof(struct crypto_skcipher, base),
	237	};
	238
	239	struct crypto_skcipher crypto_alloc_skcipher(const char alg_name,
	240	u32 type, u32 mask)
	241	{
	242	return crypto_alloc_tfm(alg_name, &crypto_skcipher_type2, type, mask);
	243	}
	244	EXPORT_SYMBOL_GPL(crypto_alloc_skcipher);
	245
	246	MODULE_LICENSE("GPL");
	247	MODULE_DESCRIPTION("Symmetric key cipher type");