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

/*
 * Asynchronous block chaining cipher operations.
 * 
 * This is the asynchronous version of blkcipher.c indicating completion
 * via a callback.
 *
 * 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/rtnetlink.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/seq_file.h>

#include "internal.h"

static int setkey_unaligned(struct crypto_ablkcipher *tfm, const u8 *key,
			    unsigned int keylen)
{
	struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
	unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
	int ret;
	u8 *buffer, *alignbuffer;
	unsigned long absize;

	absize = keylen + alignmask;
	buffer = kmalloc(absize, GFP_ATOMIC);
	if (!buffer)
		return -ENOMEM;

	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	memcpy(alignbuffer, key, keylen);
	ret = cipher->setkey(tfm, alignbuffer, keylen);
	memset(alignbuffer, 0, keylen);
	kfree(buffer);
	return ret;
}

static int setkey(struct crypto_ablkcipher *tfm, const u8 *key,
		  unsigned int keylen)
{
	struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
	unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);

	if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) {
		crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
		return -EINVAL;
	}

	if ((unsigned long)key & alignmask)
		return setkey_unaligned(tfm, key, keylen);

	return cipher->setkey(tfm, key, keylen);
}

static unsigned int crypto_ablkcipher_ctxsize(struct crypto_alg *alg, u32 type,
					      u32 mask)
{
	return alg->cra_ctxsize;
}

int skcipher_null_givencrypt(struct skcipher_givcrypt_request *req)
{
	return crypto_ablkcipher_encrypt(&req->creq);
}

int skcipher_null_givdecrypt(struct skcipher_givcrypt_request *req)
{
	return crypto_ablkcipher_decrypt(&req->creq);
}

static int crypto_init_ablkcipher_ops(struct crypto_tfm *tfm, u32 type,
				      u32 mask)
{
	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
	struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;

	if (alg->ivsize > PAGE_SIZE / 8)
		return -EINVAL;

	crt->setkey = setkey;
	crt->encrypt = alg->encrypt;
	crt->decrypt = alg->decrypt;
	if (!alg->ivsize) {
		crt->givencrypt = skcipher_null_givencrypt;
		crt->givdecrypt = skcipher_null_givdecrypt;
	}
	crt->base = __crypto_ablkcipher_cast(tfm);
	crt->ivsize = alg->ivsize;

	return 0;
}

static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg)
	__attribute__ ((unused));
static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg)
{
	struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;

	seq_printf(m, "type         : ablkcipher\n");
	seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
	seq_printf(m, "min keysize  : %u\n", ablkcipher->min_keysize);
	seq_printf(m, "max keysize  : %u\n", ablkcipher->max_keysize);
	seq_printf(m, "ivsize       : %u\n", ablkcipher->ivsize);
	seq_printf(m, "geniv        : %s\n", ablkcipher->geniv ?: "<default>");
}

const struct crypto_type crypto_ablkcipher_type = {
	.ctxsize = crypto_ablkcipher_ctxsize,
	.init = crypto_init_ablkcipher_ops,
#ifdef CONFIG_PROC_FS
	.show = crypto_ablkcipher_show,
#endif
};
EXPORT_SYMBOL_GPL(crypto_ablkcipher_type);

static int no_givdecrypt(struct skcipher_givcrypt_request *req)
{
	return -ENOSYS;
}

static int crypto_init_givcipher_ops(struct crypto_tfm *tfm, u32 type,
				      u32 mask)
{
	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
	struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;

	if (alg->ivsize > PAGE_SIZE / 8)
		return -EINVAL;

	crt->setkey = tfm->__crt_alg->cra_flags & CRYPTO_ALG_GENIV ?
		      alg->setkey : setkey;
	crt->encrypt = alg->encrypt;
	crt->decrypt = alg->decrypt;
	crt->givencrypt = alg->givencrypt;
	crt->givdecrypt = alg->givdecrypt ?: no_givdecrypt;
	crt->base = __crypto_ablkcipher_cast(tfm);
	crt->ivsize = alg->ivsize;

	return 0;
}

static void crypto_givcipher_show(struct seq_file *m, struct crypto_alg *alg)
	__attribute__ ((unused));
static void crypto_givcipher_show(struct seq_file *m, struct crypto_alg *alg)
{
	struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;

	seq_printf(m, "type         : givcipher\n");
	seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
	seq_printf(m, "min keysize  : %u\n", ablkcipher->min_keysize);
	seq_printf(m, "max keysize  : %u\n", ablkcipher->max_keysize);
	seq_printf(m, "ivsize       : %u\n", ablkcipher->ivsize);
	seq_printf(m, "geniv        : %s\n", ablkcipher->geniv ?: "<built-in>");
}

const struct crypto_type crypto_givcipher_type = {
	.ctxsize = crypto_ablkcipher_ctxsize,
	.init = crypto_init_givcipher_ops,
#ifdef CONFIG_PROC_FS
	.show = crypto_givcipher_show,
#endif
};
EXPORT_SYMBOL_GPL(crypto_givcipher_type);

const char *crypto_default_geniv(const struct crypto_alg *alg)
{
	return alg->cra_flags & CRYPTO_ALG_ASYNC ? "eseqiv" : "chainiv";
}

static int crypto_givcipher_default(struct crypto_alg *alg, u32 type, u32 mask)
{
	struct rtattr *tb[3];
	struct {
		struct rtattr attr;
		struct crypto_attr_type data;
	} ptype;
	struct {
		struct rtattr attr;
		struct crypto_attr_alg data;
	} palg;
	struct crypto_template *tmpl;
	struct crypto_instance *inst;
	struct crypto_alg *larval;
	const char *geniv;
	int err;

	larval = crypto_larval_lookup(alg->cra_driver_name,
				      CRYPTO_ALG_TYPE_GIVCIPHER,
				      CRYPTO_ALG_TYPE_MASK);
	err = PTR_ERR(larval);
	if (IS_ERR(larval))
		goto out;

	err = -EAGAIN;
	if (!crypto_is_larval(larval))
		goto drop_larval;

	ptype.attr.rta_len = sizeof(ptype);
	ptype.attr.rta_type = CRYPTOA_TYPE;
	ptype.data.type = type | CRYPTO_ALG_GENIV;
	/* GENIV tells the template that we're making a default geniv. */
	ptype.data.mask = mask | CRYPTO_ALG_GENIV;
	tb[0] = &ptype.attr;

	palg.attr.rta_len = sizeof(palg);
	palg.attr.rta_type = CRYPTOA_ALG;
	/* Must use the exact name to locate ourselves. */
	memcpy(palg.data.name, alg->cra_driver_name, CRYPTO_MAX_ALG_NAME);
	tb[1] = &palg.attr;

	tb[2] = NULL;

	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	    CRYPTO_ALG_TYPE_BLKCIPHER)
		geniv = alg->cra_blkcipher.geniv;
	else
		geniv = alg->cra_ablkcipher.geniv;

	if (!geniv)
		geniv = crypto_default_geniv(alg);

	tmpl = crypto_lookup_template(geniv);
	err = -ENOENT;
	if (!tmpl)
		goto kill_larval;

	inst = tmpl->alloc(tb);
	err = PTR_ERR(inst);
	if (IS_ERR(inst))
		goto put_tmpl;

	if ((err = crypto_register_instance(tmpl, inst))) {
		tmpl->free(inst);
		goto put_tmpl;
	}

	/* Redo the lookup to use the instance we just registered. */
	err = -EAGAIN;

put_tmpl:
	crypto_tmpl_put(tmpl);
kill_larval:
	crypto_larval_kill(larval);
drop_larval:
	crypto_mod_put(larval);
out:
	crypto_mod_put(alg);
	return err;
}

static struct crypto_alg *crypto_lookup_skcipher(const char *name, u32 type,
						 u32 mask)
{
	struct crypto_alg *alg;

	alg = crypto_alg_mod_lookup(name, type, mask);
	if (IS_ERR(alg))
		return alg;

	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	    CRYPTO_ALG_TYPE_GIVCIPHER)
		return alg;

	if (!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	      CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
					  alg->cra_ablkcipher.ivsize))
		return alg;

	return ERR_PTR(crypto_givcipher_default(alg, type, mask));
}

int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn, const char *name,
			 u32 type, u32 mask)
{
	struct crypto_alg *alg;
	int err;

	type = crypto_skcipher_type(type);
	mask = crypto_skcipher_mask(mask);

	alg = crypto_lookup_skcipher(name, type, mask);
	if (IS_ERR(alg))
		return PTR_ERR(alg);

	err = crypto_init_spawn(&spawn->base, alg, spawn->base.inst, mask);
	crypto_mod_put(alg);
	return err;
}
EXPORT_SYMBOL_GPL(crypto_grab_skcipher);

struct crypto_ablkcipher *crypto_alloc_ablkcipher(const char *alg_name,
						  u32 type, u32 mask)
{
	struct crypto_tfm *tfm;
	int err;

	type = crypto_skcipher_type(type);
	mask = crypto_skcipher_mask(mask);

	for (;;) {
		struct crypto_alg *alg;

		alg = crypto_lookup_skcipher(alg_name, type, mask);
		if (IS_ERR(alg)) {
			err = PTR_ERR(alg);
			goto err;
		}

		tfm = __crypto_alloc_tfm(alg, type, mask);
		if (!IS_ERR(tfm))
			return __crypto_ablkcipher_cast(tfm);

		crypto_mod_put(alg);
		err = PTR_ERR(tfm);

err:
		if (err != -EAGAIN)
			break;
		if (signal_pending(current)) {
			err = -EINTR;
			break;
		}
	}

	return ERR_PTR(err);
}
EXPORT_SYMBOL_GPL(crypto_alloc_ablkcipher);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Asynchronous block chaining cipher type");
Commit	Line	Data
b5b7f088 HX	1	/*
	2	* Asynchronous block chaining cipher operations.
	3	*
	4	* This is the asynchronous version of blkcipher.c indicating completion
	5	* via a callback.
	6	*
	7	* Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
	8	*
	9	* This program is free software; you can redistribute it and/or modify it
	10	* under the terms of the GNU General Public License as published by the Free
	11	* Software Foundation; either version 2 of the License, or (at your option)
	12	* any later version.
	13	*
	14	*/
	15
378f4f51 HX	16	#include <crypto/internal/skcipher.h>
378f4f51 HX	17	#include <linux/err.h>
b5b7f088	18	#include <linux/init.h>
791b4d5f	19	#include <linux/kernel.h>
b5b7f088	20	#include <linux/module.h>
b9c55aa4 HX	21	#include <linux/rtnetlink.h>
b9c55aa4 HX	22	#include <linux/sched.h>
791b4d5f	23	#include <linux/slab.h>
b5b7f088 HX	24	#include <linux/seq_file.h>
b5b7f088 HX	25
378f4f51 HX	26	#include "internal.h"
378f4f51 HX	27
791b4d5f HX	28	static int setkey_unaligned(struct crypto_ablkcipher tfm, const u8 key,
791b4d5f HX	29	unsigned int keylen)
ca7c3938 SS	30	{
	31	struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
	32	unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
	33	int ret;
	34	u8 buffer, alignbuffer;
	35	unsigned long absize;
	36
	37	absize = keylen + alignmask;
	38	buffer = kmalloc(absize, GFP_ATOMIC);
	39	if (!buffer)
	40	return -ENOMEM;
	41
	42	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	43	memcpy(alignbuffer, key, keylen);
	44	ret = cipher->setkey(tfm, alignbuffer, keylen);
06817176	45	memset(alignbuffer, 0, keylen);
ca7c3938 SS	46	kfree(buffer);
	47	return ret;
	48	}
	49
b5b7f088 HX	50	static int setkey(struct crypto_ablkcipher tfm, const u8 key,
	51	unsigned int keylen)
	52	{
	53	struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
ca7c3938	54	unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
b5b7f088 HX	55
	56	if (keylen < cipher->min_keysize \|\| keylen > cipher->max_keysize) {
	57	crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
	58	return -EINVAL;
	59	}
	60
ca7c3938 SS	61	if ((unsigned long)key & alignmask)
	62	return setkey_unaligned(tfm, key, keylen);
	63
b5b7f088 HX	64	return cipher->setkey(tfm, key, keylen);
	65	}
	66
	67	static unsigned int crypto_ablkcipher_ctxsize(struct crypto_alg *alg, u32 type,
	68	u32 mask)
	69	{
	70	return alg->cra_ctxsize;
	71	}
	72
b9c55aa4 HX	73	int skcipher_null_givencrypt(struct skcipher_givcrypt_request *req)
	74	{
	75	return crypto_ablkcipher_encrypt(&req->creq);
	76	}
	77
	78	int skcipher_null_givdecrypt(struct skcipher_givcrypt_request *req)
	79	{
	80	return crypto_ablkcipher_decrypt(&req->creq);
	81	}
	82
b5b7f088 HX	83	static int crypto_init_ablkcipher_ops(struct crypto_tfm *tfm, u32 type,
	84	u32 mask)
	85	{
	86	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
	87	struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
	88
	89	if (alg->ivsize > PAGE_SIZE / 8)
	90	return -EINVAL;
	91
	92	crt->setkey = setkey;
	93	crt->encrypt = alg->encrypt;
	94	crt->decrypt = alg->decrypt;
b9c55aa4 HX	95	if (!alg->ivsize) {
	96	crt->givencrypt = skcipher_null_givencrypt;
	97	crt->givdecrypt = skcipher_null_givdecrypt;
	98	}
ecfc4329	99	crt->base = __crypto_ablkcipher_cast(tfm);
b5b7f088 HX	100	crt->ivsize = alg->ivsize;
	101
	102	return 0;
	103	}
	104
	105	static void crypto_ablkcipher_show(struct seq_file m, struct crypto_alg alg)
	106	__attribute__ ((unused));
	107	static void crypto_ablkcipher_show(struct seq_file m, struct crypto_alg alg)
	108	{
	109	struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;
	110
	111	seq_printf(m, "type : ablkcipher\n");
	112	seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
	113	seq_printf(m, "min keysize : %u\n", ablkcipher->min_keysize);
	114	seq_printf(m, "max keysize : %u\n", ablkcipher->max_keysize);
	115	seq_printf(m, "ivsize : %u\n", ablkcipher->ivsize);
23508e11	116	seq_printf(m, "geniv : %s\n", ablkcipher->geniv ?: "<default>");
b5b7f088 HX	117	}
	118
	119	const struct crypto_type crypto_ablkcipher_type = {
	120	.ctxsize = crypto_ablkcipher_ctxsize,
	121	.init = crypto_init_ablkcipher_ops,
	122	#ifdef CONFIG_PROC_FS
	123	.show = crypto_ablkcipher_show,
	124	#endif
	125	};
	126	EXPORT_SYMBOL_GPL(crypto_ablkcipher_type);
	127
61da88e2 HX	128	static int no_givdecrypt(struct skcipher_givcrypt_request *req)
	129	{
	130	return -ENOSYS;
	131	}
	132
	133	static int crypto_init_givcipher_ops(struct crypto_tfm *tfm, u32 type,
	134	u32 mask)
	135	{
	136	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
	137	struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
	138
	139	if (alg->ivsize > PAGE_SIZE / 8)
	140	return -EINVAL;
	141
ecfc4329 HX	142	crt->setkey = tfm->__crt_alg->cra_flags & CRYPTO_ALG_GENIV ?
ecfc4329 HX	143	alg->setkey : setkey;
61da88e2 HX	144	crt->encrypt = alg->encrypt;
	145	crt->decrypt = alg->decrypt;
	146	crt->givencrypt = alg->givencrypt;
	147	crt->givdecrypt = alg->givdecrypt ?: no_givdecrypt;
ecfc4329	148	crt->base = __crypto_ablkcipher_cast(tfm);
61da88e2 HX	149	crt->ivsize = alg->ivsize;
	150
	151	return 0;
	152	}
	153
	154	static void crypto_givcipher_show(struct seq_file m, struct crypto_alg alg)
	155	__attribute__ ((unused));
	156	static void crypto_givcipher_show(struct seq_file m, struct crypto_alg alg)
	157	{
	158	struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;
	159
	160	seq_printf(m, "type : givcipher\n");
	161	seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
	162	seq_printf(m, "min keysize : %u\n", ablkcipher->min_keysize);
	163	seq_printf(m, "max keysize : %u\n", ablkcipher->max_keysize);
	164	seq_printf(m, "ivsize : %u\n", ablkcipher->ivsize);
23508e11	165	seq_printf(m, "geniv : %s\n", ablkcipher->geniv ?: "<built-in>");
61da88e2 HX	166	}
	167
	168	const struct crypto_type crypto_givcipher_type = {
	169	.ctxsize = crypto_ablkcipher_ctxsize,
	170	.init = crypto_init_givcipher_ops,
	171	#ifdef CONFIG_PROC_FS
	172	.show = crypto_givcipher_show,
	173	#endif
	174	};
	175	EXPORT_SYMBOL_GPL(crypto_givcipher_type);
	176
ecfc4329 HX	177	const char crypto_default_geniv(const struct crypto_alg alg)
	178	{
	179	return alg->cra_flags & CRYPTO_ALG_ASYNC ? "eseqiv" : "chainiv";
	180	}
	181
b9c55aa4 HX	182	static int crypto_givcipher_default(struct crypto_alg *alg, u32 type, u32 mask)
	183	{
	184	struct rtattr *tb[3];
	185	struct {
	186	struct rtattr attr;
	187	struct crypto_attr_type data;
	188	} ptype;
	189	struct {
	190	struct rtattr attr;
	191	struct crypto_attr_alg data;
	192	} palg;
	193	struct crypto_template *tmpl;
	194	struct crypto_instance *inst;
	195	struct crypto_alg *larval;
	196	const char *geniv;
	197	int err;
	198
	199	larval = crypto_larval_lookup(alg->cra_driver_name,
	200	CRYPTO_ALG_TYPE_GIVCIPHER,
	201	CRYPTO_ALG_TYPE_MASK);
	202	err = PTR_ERR(larval);
	203	if (IS_ERR(larval))
	204	goto out;
	205
	206	err = -EAGAIN;
	207	if (!crypto_is_larval(larval))
	208	goto drop_larval;
	209
	210	ptype.attr.rta_len = sizeof(ptype);
	211	ptype.attr.rta_type = CRYPTOA_TYPE;
	212	ptype.data.type = type \| CRYPTO_ALG_GENIV;
	213	/* GENIV tells the template that we're making a default geniv. */
	214	ptype.data.mask = mask \| CRYPTO_ALG_GENIV;
	215	tb[0] = &ptype.attr;
	216
	217	palg.attr.rta_len = sizeof(palg);
	218	palg.attr.rta_type = CRYPTOA_ALG;
	219	/* Must use the exact name to locate ourselves. */
	220	memcpy(palg.data.name, alg->cra_driver_name, CRYPTO_MAX_ALG_NAME);
	221	tb[1] = &palg.attr;
	222
	223	tb[2] = NULL;
	224
	225	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	226	CRYPTO_ALG_TYPE_BLKCIPHER)
	227	geniv = alg->cra_blkcipher.geniv;
	228	else
	229	geniv = alg->cra_ablkcipher.geniv;
	230
	231	if (!geniv)
	232	geniv = crypto_default_geniv(alg);
	233
	234	tmpl = crypto_lookup_template(geniv);
	235	err = -ENOENT;
	236	if (!tmpl)
	237	goto kill_larval;
	238
	239	inst = tmpl->alloc(tb);
	240	err = PTR_ERR(inst);
	241	if (IS_ERR(inst))
	242	goto put_tmpl;
	243
	244	if ((err = crypto_register_instance(tmpl, inst))) {
	245	tmpl->free(inst);
246	goto put_tmpl;
247	}
248
249	/* Redo the lookup to use the instance we just registered. */
250	err = -EAGAIN;
251
252	put_tmpl:
253	crypto_tmpl_put(tmpl);
254	kill_larval:
255	crypto_larval_kill(larval);
256	drop_larval:
257	crypto_mod_put(larval);
258	out:
259	crypto_mod_put(alg);
260	return err;
261	}
262
263	static struct crypto_alg crypto_lookup_skcipher(const char name, u32 type,
264	u32 mask)
265	{
266	struct crypto_alg *alg;
267
268	alg = crypto_alg_mod_lookup(name, type, mask);
269	if (IS_ERR(alg))
270	return alg;
271
272	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
273	CRYPTO_ALG_TYPE_GIVCIPHER)
274	return alg;
275
276	if (!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
277	CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
278	alg->cra_ablkcipher.ivsize))
279	return alg;
280
281	return ERR_PTR(crypto_givcipher_default(alg, type, mask));
282	}
283
378f4f51 HX	284	int crypto_grab_skcipher(struct crypto_skcipher_spawn spawn, const char name,
	285	u32 type, u32 mask)
	286	{
	287	struct crypto_alg *alg;
	288	int err;
	289
	290	type = crypto_skcipher_type(type);
	291	mask = crypto_skcipher_mask(mask);
	292
b9c55aa4	293	alg = crypto_lookup_skcipher(name, type, mask);
378f4f51 HX	294	if (IS_ERR(alg))
	295	return PTR_ERR(alg);
	296
	297	err = crypto_init_spawn(&spawn->base, alg, spawn->base.inst, mask);
	298	crypto_mod_put(alg);
	299	return err;
	300	}
	301	EXPORT_SYMBOL_GPL(crypto_grab_skcipher);
	302
b9c55aa4 HX	303	struct crypto_ablkcipher crypto_alloc_ablkcipher(const char alg_name,
	304	u32 type, u32 mask)
	305	{
	306	struct crypto_tfm *tfm;
	307	int err;
	308
	309	type = crypto_skcipher_type(type);
	310	mask = crypto_skcipher_mask(mask);
	311
	312	for (;;) {
	313	struct crypto_alg *alg;
	314
	315	alg = crypto_lookup_skcipher(alg_name, type, mask);
	316	if (IS_ERR(alg)) {
	317	err = PTR_ERR(alg);
	318	goto err;
	319	}
	320
	321	tfm = __crypto_alloc_tfm(alg, type, mask);
	322	if (!IS_ERR(tfm))
	323	return __crypto_ablkcipher_cast(tfm);
	324
	325	crypto_mod_put(alg);
	326	err = PTR_ERR(tfm);
	327
	328	err:
	329	if (err != -EAGAIN)
	330	break;
	331	if (signal_pending(current)) {
	332	err = -EINTR;
	333	break;
	334	}
	335	}
	336
	337	return ERR_PTR(err);
	338	}
	339	EXPORT_SYMBOL_GPL(crypto_alloc_ablkcipher);
	340
b5b7f088 HX	341	MODULE_LICENSE("GPL");
b5b7f088 HX	342	MODULE_DESCRIPTION("Asynchronous block chaining cipher type");