[mirror_ubuntu-bionic-kernel.git] / crypto / chainiv.c

/*
 * chainiv: Chain IV Generator
 *
 * Generate IVs simply be using the last block of the previous encryption.
 * This is mainly useful for CBC with a synchronous algorithm.
 *
 * Copyright (c) 2007 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 <crypto/rng.h>
#include <crypto/crypto_wq.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/workqueue.h>

enum {
	CHAINIV_STATE_INUSE = 0,
};

struct chainiv_ctx {
	spinlock_t lock;
	char iv[];
};

struct async_chainiv_ctx {
	unsigned long state;

	spinlock_t lock;
	int err;

	struct crypto_queue queue;
	struct work_struct postponed;

	char iv[];
};

static int chainiv_givencrypt(struct skcipher_givcrypt_request *req)
{
	struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req);
	struct chainiv_ctx *ctx = crypto_ablkcipher_ctx(geniv);
	struct ablkcipher_request *subreq = skcipher_givcrypt_reqctx(req);
	unsigned int ivsize;
	int err;

	ablkcipher_request_set_tfm(subreq, skcipher_geniv_cipher(geniv));
	ablkcipher_request_set_callback(subreq, req->creq.base.flags &
						~CRYPTO_TFM_REQ_MAY_SLEEP,
					req->creq.base.complete,
					req->creq.base.data);
	ablkcipher_request_set_crypt(subreq, req->creq.src, req->creq.dst,
				     req->creq.nbytes, req->creq.info);

	spin_lock_bh(&ctx->lock);

	ivsize = crypto_ablkcipher_ivsize(geniv);

	memcpy(req->giv, ctx->iv, ivsize);
	memcpy(subreq->info, ctx->iv, ivsize);

	err = crypto_ablkcipher_encrypt(subreq);
	if (err)
		goto unlock;

	memcpy(ctx->iv, subreq->info, ivsize);

unlock:
	spin_unlock_bh(&ctx->lock);

	return err;
}

static int chainiv_givencrypt_first(struct skcipher_givcrypt_request *req)
{
	struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req);
	struct chainiv_ctx *ctx = crypto_ablkcipher_ctx(geniv);
	int err = 0;

	spin_lock_bh(&ctx->lock);
	if (crypto_ablkcipher_crt(geniv)->givencrypt !=
	    chainiv_givencrypt_first)
		goto unlock;

	crypto_ablkcipher_crt(geniv)->givencrypt = chainiv_givencrypt;
	err = crypto_rng_get_bytes(crypto_default_rng, ctx->iv,
				   crypto_ablkcipher_ivsize(geniv));

unlock:
	spin_unlock_bh(&ctx->lock);

	if (err)
		return err;

	return chainiv_givencrypt(req);
}

static int chainiv_init_common(struct crypto_tfm *tfm)
{
	tfm->crt_ablkcipher.reqsize = sizeof(struct ablkcipher_request);

	return skcipher_geniv_init(tfm);
}

static int chainiv_init(struct crypto_tfm *tfm)
{
	struct chainiv_ctx *ctx = crypto_tfm_ctx(tfm);

	spin_lock_init(&ctx->lock);

	return chainiv_init_common(tfm);
}

static int async_chainiv_schedule_work(struct async_chainiv_ctx *ctx)
{
	int queued;
	int err = ctx->err;

	if (!ctx->queue.qlen) {
		smp_mb__before_clear_bit();
		clear_bit(CHAINIV_STATE_INUSE, &ctx->state);

		if (!ctx->queue.qlen ||
		    test_and_set_bit(CHAINIV_STATE_INUSE, &ctx->state))
			goto out;
	}

	queued = queue_work(kcrypto_wq, &ctx->postponed);
	BUG_ON(!queued);

out:
	return err;
}

static int async_chainiv_postpone_request(struct skcipher_givcrypt_request *req)
{
	struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req);
	struct async_chainiv_ctx *ctx = crypto_ablkcipher_ctx(geniv);
	int err;

	spin_lock_bh(&ctx->lock);
	err = skcipher_enqueue_givcrypt(&ctx->queue, req);
	spin_unlock_bh(&ctx->lock);

	if (test_and_set_bit(CHAINIV_STATE_INUSE, &ctx->state))
		return err;

	ctx->err = err;
	return async_chainiv_schedule_work(ctx);
}

static int async_chainiv_givencrypt_tail(struct skcipher_givcrypt_request *req)
{
	struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req);
	struct async_chainiv_ctx *ctx = crypto_ablkcipher_ctx(geniv);
	struct ablkcipher_request *subreq = skcipher_givcrypt_reqctx(req);
	unsigned int ivsize = crypto_ablkcipher_ivsize(geniv);

	memcpy(req->giv, ctx->iv, ivsize);
	memcpy(subreq->info, ctx->iv, ivsize);

	ctx->err = crypto_ablkcipher_encrypt(subreq);
	if (ctx->err)
		goto out;

	memcpy(ctx->iv, subreq->info, ivsize);

out:
	return async_chainiv_schedule_work(ctx);
}

static int async_chainiv_givencrypt(struct skcipher_givcrypt_request *req)
{
	struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req);
	struct async_chainiv_ctx *ctx = crypto_ablkcipher_ctx(geniv);
	struct ablkcipher_request *subreq = skcipher_givcrypt_reqctx(req);

	ablkcipher_request_set_tfm(subreq, skcipher_geniv_cipher(geniv));
	ablkcipher_request_set_callback(subreq, req->creq.base.flags,
					req->creq.base.complete,
					req->creq.base.data);
	ablkcipher_request_set_crypt(subreq, req->creq.src, req->creq.dst,
				     req->creq.nbytes, req->creq.info);

	if (test_and_set_bit(CHAINIV_STATE_INUSE, &ctx->state))
		goto postpone;

	if (ctx->queue.qlen) {
		clear_bit(CHAINIV_STATE_INUSE, &ctx->state);
		goto postpone;
	}

	return async_chainiv_givencrypt_tail(req);

postpone:
	return async_chainiv_postpone_request(req);
}

static int async_chainiv_givencrypt_first(struct skcipher_givcrypt_request *req)
{
	struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req);
	struct async_chainiv_ctx *ctx = crypto_ablkcipher_ctx(geniv);
	int err = 0;

	if (test_and_set_bit(CHAINIV_STATE_INUSE, &ctx->state))
		goto out;

	if (crypto_ablkcipher_crt(geniv)->givencrypt !=
	    async_chainiv_givencrypt_first)
		goto unlock;

	crypto_ablkcipher_crt(geniv)->givencrypt = async_chainiv_givencrypt;
	err = crypto_rng_get_bytes(crypto_default_rng, ctx->iv,
				   crypto_ablkcipher_ivsize(geniv));

unlock:
	clear_bit(CHAINIV_STATE_INUSE, &ctx->state);

	if (err)
		return err;

out:
	return async_chainiv_givencrypt(req);
}

static void async_chainiv_do_postponed(struct work_struct *work)
{
	struct async_chainiv_ctx *ctx = container_of(work,
						     struct async_chainiv_ctx,
						     postponed);
	struct skcipher_givcrypt_request *req;
	struct ablkcipher_request *subreq;
	int err;

	/* Only handle one request at a time to avoid hogging keventd. */
	spin_lock_bh(&ctx->lock);
	req = skcipher_dequeue_givcrypt(&ctx->queue);
	spin_unlock_bh(&ctx->lock);

	if (!req) {
		async_chainiv_schedule_work(ctx);
		return;
	}

	subreq = skcipher_givcrypt_reqctx(req);
	subreq->base.flags |= CRYPTO_TFM_REQ_MAY_SLEEP;

	err = async_chainiv_givencrypt_tail(req);

	local_bh_disable();
	skcipher_givcrypt_complete(req, err);
	local_bh_enable();
}

static int async_chainiv_init(struct crypto_tfm *tfm)
{
	struct async_chainiv_ctx *ctx = crypto_tfm_ctx(tfm);

	spin_lock_init(&ctx->lock);

	crypto_init_queue(&ctx->queue, 100);
	INIT_WORK(&ctx->postponed, async_chainiv_do_postponed);

	return chainiv_init_common(tfm);
}

static void async_chainiv_exit(struct crypto_tfm *tfm)
{
	struct async_chainiv_ctx *ctx = crypto_tfm_ctx(tfm);

	BUG_ON(test_bit(CHAINIV_STATE_INUSE, &ctx->state) || ctx->queue.qlen);

	skcipher_geniv_exit(tfm);
}

static struct crypto_template chainiv_tmpl;

static struct crypto_instance *chainiv_alloc(struct rtattr **tb)
{
	struct crypto_attr_type *algt;
	struct crypto_instance *inst;
	int err;

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

	err = crypto_get_default_rng();
	if (err)
		return ERR_PTR(err);

	inst = skcipher_geniv_alloc(&chainiv_tmpl, tb, 0, 0);
	if (IS_ERR(inst))
		goto put_rng;

	inst->alg.cra_ablkcipher.givencrypt = chainiv_givencrypt_first;

	inst->alg.cra_init = chainiv_init;
	inst->alg.cra_exit = skcipher_geniv_exit;

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

	if (!crypto_requires_sync(algt->type, algt->mask)) {
		inst->alg.cra_flags |= CRYPTO_ALG_ASYNC;

		inst->alg.cra_ablkcipher.givencrypt =
			async_chainiv_givencrypt_first;

		inst->alg.cra_init = async_chainiv_init;
		inst->alg.cra_exit = async_chainiv_exit;

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

	inst->alg.cra_ctxsize += inst->alg.cra_ablkcipher.ivsize;

out:
	return inst;

put_rng:
	crypto_put_default_rng();
	goto out;
}

static void chainiv_free(struct crypto_instance *inst)
{
	skcipher_geniv_free(inst);
	crypto_put_default_rng();
}

static struct crypto_template chainiv_tmpl = {
	.name = "chainiv",
	.alloc = chainiv_alloc,
	.free = chainiv_free,
	.module = THIS_MODULE,
};

static int __init chainiv_module_init(void)
{
	return crypto_register_template(&chainiv_tmpl);
}

static void chainiv_module_exit(void)
{
	crypto_unregister_template(&chainiv_tmpl);
}

module_init(chainiv_module_init);
module_exit(chainiv_module_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Chain IV Generator");
Commit	Line	Data
7f470739 HX	1	/*
	2	* chainiv: Chain IV Generator
	3	*
	4	* Generate IVs simply be using the last block of the previous encryption.
	5	* This is mainly useful for CBC with a synchronous algorithm.
	6	*
	7	* Copyright (c) 2007 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
	16	#include <crypto/internal/skcipher.h>
a0f000ec	17	#include <crypto/rng.h>
0a2e821d	18	#include <crypto/crypto_wq.h>
7f470739 HX	19	#include <linux/err.h>
7f470739 HX	20	#include <linux/init.h>
e7cd2514	21	#include <linux/kernel.h>
7f470739	22	#include <linux/module.h>
7f470739 HX	23	#include <linux/spinlock.h>
7f470739 HX	24	#include <linux/string.h>
e7cd2514 HX	25	#include <linux/workqueue.h>
	26
	27	enum {
	28	CHAINIV_STATE_INUSE = 0,
	29	};
7f470739 HX	30
	31	struct chainiv_ctx {
	32	spinlock_t lock;
	33	char iv[];
	34	};
	35
e7cd2514 HX	36	struct async_chainiv_ctx {
	37	unsigned long state;
	38
	39	spinlock_t lock;
	40	int err;
	41
	42	struct crypto_queue queue;
	43	struct work_struct postponed;
	44
	45	char iv[];
	46	};
	47
7f470739 HX	48	static int chainiv_givencrypt(struct skcipher_givcrypt_request *req)
	49	{
	50	struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req);
	51	struct chainiv_ctx *ctx = crypto_ablkcipher_ctx(geniv);
	52	struct ablkcipher_request *subreq = skcipher_givcrypt_reqctx(req);
	53	unsigned int ivsize;
	54	int err;
	55
	56	ablkcipher_request_set_tfm(subreq, skcipher_geniv_cipher(geniv));
	57	ablkcipher_request_set_callback(subreq, req->creq.base.flags &
	58	~CRYPTO_TFM_REQ_MAY_SLEEP,
	59	req->creq.base.complete,
	60	req->creq.base.data);
	61	ablkcipher_request_set_crypt(subreq, req->creq.src, req->creq.dst,
	62	req->creq.nbytes, req->creq.info);
	63
	64	spin_lock_bh(&ctx->lock);
	65
	66	ivsize = crypto_ablkcipher_ivsize(geniv);
	67
	68	memcpy(req->giv, ctx->iv, ivsize);
	69	memcpy(subreq->info, ctx->iv, ivsize);
	70
	71	err = crypto_ablkcipher_encrypt(subreq);
	72	if (err)
	73	goto unlock;
	74
	75	memcpy(ctx->iv, subreq->info, ivsize);
	76
	77	unlock:
	78	spin_unlock_bh(&ctx->lock);
	79
	80	return err;
	81	}
	82
	83	static int chainiv_givencrypt_first(struct skcipher_givcrypt_request *req)
	84	{
	85	struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req);
	86	struct chainiv_ctx *ctx = crypto_ablkcipher_ctx(geniv);
a0f000ec	87	int err = 0;
7f470739 HX	88
	89	spin_lock_bh(&ctx->lock);
	90	if (crypto_ablkcipher_crt(geniv)->givencrypt !=
	91	chainiv_givencrypt_first)
	92	goto unlock;
	93
	94	crypto_ablkcipher_crt(geniv)->givencrypt = chainiv_givencrypt;
a0f000ec HX	95	err = crypto_rng_get_bytes(crypto_default_rng, ctx->iv,
a0f000ec HX	96	crypto_ablkcipher_ivsize(geniv));
7f470739 HX	97
	98	unlock:
	99	spin_unlock_bh(&ctx->lock);
	100
a0f000ec HX	101	if (err)
	102	return err;
	103
7f470739 HX	104	return chainiv_givencrypt(req);
	105	}
	106
e7cd2514 HX	107	static int chainiv_init_common(struct crypto_tfm *tfm)
	108	{
	109	tfm->crt_ablkcipher.reqsize = sizeof(struct ablkcipher_request);
	110
	111	return skcipher_geniv_init(tfm);
	112	}
	113
7f470739 HX	114	static int chainiv_init(struct crypto_tfm *tfm)
7f470739 HX	115	{
e7cd2514	116	struct chainiv_ctx *ctx = crypto_tfm_ctx(tfm);
7f470739 HX	117
	118	spin_lock_init(&ctx->lock);
	119
e7cd2514 HX	120	return chainiv_init_common(tfm);
e7cd2514 HX	121	}
7f470739	122
e7cd2514 HX	123	static int async_chainiv_schedule_work(struct async_chainiv_ctx *ctx)
	124	{
	125	int queued;
872ac874	126	int err = ctx->err;
e7cd2514 HX	127
	128	if (!ctx->queue.qlen) {
	129	smp_mb__before_clear_bit();
	130	clear_bit(CHAINIV_STATE_INUSE, &ctx->state);
	131
	132	if (!ctx->queue.qlen \|\|
	133	test_and_set_bit(CHAINIV_STATE_INUSE, &ctx->state))
	134	goto out;
	135	}
	136
0a2e821d	137	queued = queue_work(kcrypto_wq, &ctx->postponed);
e7cd2514 HX	138	BUG_ON(!queued);
	139
	140	out:
872ac874	141	return err;
e7cd2514 HX	142	}
	143
	144	static int async_chainiv_postpone_request(struct skcipher_givcrypt_request *req)
	145	{
	146	struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req);
	147	struct async_chainiv_ctx *ctx = crypto_ablkcipher_ctx(geniv);
	148	int err;
	149
	150	spin_lock_bh(&ctx->lock);
	151	err = skcipher_enqueue_givcrypt(&ctx->queue, req);
	152	spin_unlock_bh(&ctx->lock);
	153
	154	if (test_and_set_bit(CHAINIV_STATE_INUSE, &ctx->state))
	155	return err;
	156
	157	ctx->err = err;
	158	return async_chainiv_schedule_work(ctx);
	159	}
	160
	161	static int async_chainiv_givencrypt_tail(struct skcipher_givcrypt_request *req)
	162	{
	163	struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req);
	164	struct async_chainiv_ctx *ctx = crypto_ablkcipher_ctx(geniv);
	165	struct ablkcipher_request *subreq = skcipher_givcrypt_reqctx(req);
	166	unsigned int ivsize = crypto_ablkcipher_ivsize(geniv);
	167
	168	memcpy(req->giv, ctx->iv, ivsize);
	169	memcpy(subreq->info, ctx->iv, ivsize);
	170
	171	ctx->err = crypto_ablkcipher_encrypt(subreq);
	172	if (ctx->err)
	173	goto out;
	174
	175	memcpy(ctx->iv, subreq->info, ivsize);
	176
	177	out:
	178	return async_chainiv_schedule_work(ctx);
	179	}
	180
	181	static int async_chainiv_givencrypt(struct skcipher_givcrypt_request *req)
	182	{
	183	struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req);
	184	struct async_chainiv_ctx *ctx = crypto_ablkcipher_ctx(geniv);
	185	struct ablkcipher_request *subreq = skcipher_givcrypt_reqctx(req);
	186
	187	ablkcipher_request_set_tfm(subreq, skcipher_geniv_cipher(geniv));
	188	ablkcipher_request_set_callback(subreq, req->creq.base.flags,
	189	req->creq.base.complete,
	190	req->creq.base.data);
	191	ablkcipher_request_set_crypt(subreq, req->creq.src, req->creq.dst,
	192	req->creq.nbytes, req->creq.info);
	193
	194	if (test_and_set_bit(CHAINIV_STATE_INUSE, &ctx->state))
	195	goto postpone;
	196
	197	if (ctx->queue.qlen) {
	198	clear_bit(CHAINIV_STATE_INUSE, &ctx->state);
	199	goto postpone;
	200	}
	201
	202	return async_chainiv_givencrypt_tail(req);
	203
	204	postpone:
	205	return async_chainiv_postpone_request(req);
206	}
207
208	static int async_chainiv_givencrypt_first(struct skcipher_givcrypt_request *req)
209	{
210	struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req);
211	struct async_chainiv_ctx *ctx = crypto_ablkcipher_ctx(geniv);
a0f000ec	212	int err = 0;
e7cd2514 HX	213
	214	if (test_and_set_bit(CHAINIV_STATE_INUSE, &ctx->state))
	215	goto out;
	216
	217	if (crypto_ablkcipher_crt(geniv)->givencrypt !=
	218	async_chainiv_givencrypt_first)
	219	goto unlock;
	220
	221	crypto_ablkcipher_crt(geniv)->givencrypt = async_chainiv_givencrypt;
a0f000ec HX	222	err = crypto_rng_get_bytes(crypto_default_rng, ctx->iv,
a0f000ec HX	223	crypto_ablkcipher_ivsize(geniv));
e7cd2514 HX	224
	225	unlock:
	226	clear_bit(CHAINIV_STATE_INUSE, &ctx->state);
	227
a0f000ec HX	228	if (err)
	229	return err;
	230
e7cd2514 HX	231	out:
	232	return async_chainiv_givencrypt(req);
	233	}
	234
	235	static void async_chainiv_do_postponed(struct work_struct *work)
	236	{
	237	struct async_chainiv_ctx *ctx = container_of(work,
	238	struct async_chainiv_ctx,
	239	postponed);
	240	struct skcipher_givcrypt_request *req;
	241	struct ablkcipher_request *subreq;
872ac874	242	int err;
e7cd2514 HX	243
	244	/* Only handle one request at a time to avoid hogging keventd. */
	245	spin_lock_bh(&ctx->lock);
	246	req = skcipher_dequeue_givcrypt(&ctx->queue);
	247	spin_unlock_bh(&ctx->lock);
	248
	249	if (!req) {
	250	async_chainiv_schedule_work(ctx);
	251	return;
	252	}
	253
	254	subreq = skcipher_givcrypt_reqctx(req);
	255	subreq->base.flags \|= CRYPTO_TFM_REQ_MAY_SLEEP;
	256
872ac874 HX	257	err = async_chainiv_givencrypt_tail(req);
	258
	259	local_bh_disable();
	260	skcipher_givcrypt_complete(req, err);
	261	local_bh_enable();
e7cd2514 HX	262	}
	263
	264	static int async_chainiv_init(struct crypto_tfm *tfm)
	265	{
	266	struct async_chainiv_ctx *ctx = crypto_tfm_ctx(tfm);
	267
	268	spin_lock_init(&ctx->lock);
	269
	270	crypto_init_queue(&ctx->queue, 100);
	271	INIT_WORK(&ctx->postponed, async_chainiv_do_postponed);
	272
	273	return chainiv_init_common(tfm);
	274	}
	275
	276	static void async_chainiv_exit(struct crypto_tfm *tfm)
	277	{
	278	struct async_chainiv_ctx *ctx = crypto_tfm_ctx(tfm);
	279
	280	BUG_ON(test_bit(CHAINIV_STATE_INUSE, &ctx->state) \|\| ctx->queue.qlen);
	281
	282	skcipher_geniv_exit(tfm);
7f470739 HX	283	}
	284
	285	static struct crypto_template chainiv_tmpl;
	286
	287	static struct crypto_instance chainiv_alloc(struct rtattr *tb)
	288	{
e7cd2514	289	struct crypto_attr_type *algt;
7f470739	290	struct crypto_instance *inst;
e7cd2514	291	int err;
7f470739	292
e7cd2514	293	algt = crypto_get_attr_type(tb);
e7cd2514	294	if (IS_ERR(algt))
3e8afe35	295	return ERR_CAST(algt);
e7cd2514	296
a0f000ec HX	297	err = crypto_get_default_rng();
	298	if (err)
	299	return ERR_PTR(err);
	300
e7cd2514	301	inst = skcipher_geniv_alloc(&chainiv_tmpl, tb, 0, 0);
7f470739	302	if (IS_ERR(inst))
a0f000ec	303	goto put_rng;
7f470739 HX	304
	305	inst->alg.cra_ablkcipher.givencrypt = chainiv_givencrypt_first;
	306
	307	inst->alg.cra_init = chainiv_init;
	308	inst->alg.cra_exit = skcipher_geniv_exit;
	309
e7cd2514 HX	310	inst->alg.cra_ctxsize = sizeof(struct chainiv_ctx);
	311
	312	if (!crypto_requires_sync(algt->type, algt->mask)) {
	313	inst->alg.cra_flags \|= CRYPTO_ALG_ASYNC;
	314
	315	inst->alg.cra_ablkcipher.givencrypt =
	316	async_chainiv_givencrypt_first;
	317
	318	inst->alg.cra_init = async_chainiv_init;
	319	inst->alg.cra_exit = async_chainiv_exit;
	320
	321	inst->alg.cra_ctxsize = sizeof(struct async_chainiv_ctx);
	322	}
	323
	324	inst->alg.cra_ctxsize += inst->alg.cra_ablkcipher.ivsize;
7f470739 HX	325
	326	out:
	327	return inst;
a0f000ec HX	328
	329	put_rng:
	330	crypto_put_default_rng();
	331	goto out;
	332	}
	333
	334	static void chainiv_free(struct crypto_instance *inst)
	335	{
	336	skcipher_geniv_free(inst);
	337	crypto_put_default_rng();
7f470739 HX	338	}
	339
	340	static struct crypto_template chainiv_tmpl = {
	341	.name = "chainiv",
	342	.alloc = chainiv_alloc,
a0f000ec	343	.free = chainiv_free,
7f470739 HX	344	.module = THIS_MODULE,
	345	};
	346
5be5e667	347	static int __init chainiv_module_init(void)
7f470739 HX	348	{
	349	return crypto_register_template(&chainiv_tmpl);
	350	}
	351
5be5e667	352	static void chainiv_module_exit(void)
7f470739 HX	353	{
	354	crypto_unregister_template(&chainiv_tmpl);
	355	}
5be5e667 HX	356
	357	module_init(chainiv_module_init);
	358	module_exit(chainiv_module_exit);
	359
	360	MODULE_LICENSE("GPL");
	361	MODULE_DESCRIPTION("Chain IV Generator");