[GitHub/mt8127/android_kernel_alcatel_ttab.git] / crypto / seqiv.c

/*
 * seqiv: Sequence Number IV Generator
 *
 * This generator generates an IV based on a sequence number by xoring it
 * with a salt.  This algorithm is mainly useful for CTR and similar modes.
 *
 * 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/aead.h>
#include <crypto/internal/skcipher.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/random.h>
#include <linux/spinlock.h>
#include <linux/string.h>

struct seqiv_ctx {
	spinlock_t lock;
	u8 salt[] __attribute__ ((aligned(__alignof__(u32))));
};

static void seqiv_complete2(struct skcipher_givcrypt_request *req, int err)
{
	struct ablkcipher_request *subreq = skcipher_givcrypt_reqctx(req);
	struct crypto_ablkcipher *geniv;

	if (err == -EINPROGRESS)
		return;

	if (err)
		goto out;

	geniv = skcipher_givcrypt_reqtfm(req);
	memcpy(req->creq.info, subreq->info, crypto_ablkcipher_ivsize(geniv));

out:
	kfree(subreq->info);
}

static void seqiv_complete(struct crypto_async_request *base, int err)
{
	struct skcipher_givcrypt_request *req = base->data;

	seqiv_complete2(req, err);
	skcipher_givcrypt_complete(req, err);
}

static void seqiv_aead_complete2(struct aead_givcrypt_request *req, int err)
{
	struct aead_request *subreq = aead_givcrypt_reqctx(req);
	struct crypto_aead *geniv;

	if (err == -EINPROGRESS)
		return;

	if (err)
		goto out;

	geniv = aead_givcrypt_reqtfm(req);
	memcpy(req->areq.iv, subreq->iv, crypto_aead_ivsize(geniv));

out:
	kfree(subreq->iv);
}

static void seqiv_aead_complete(struct crypto_async_request *base, int err)
{
	struct aead_givcrypt_request *req = base->data;

	seqiv_aead_complete2(req, err);
	aead_givcrypt_complete(req, err);
}

static void seqiv_geniv(struct seqiv_ctx *ctx, u8 *info, u64 seq,
			unsigned int ivsize)
{
	unsigned int len = ivsize;

	if (ivsize > sizeof(u64)) {
		memset(info, 0, ivsize - sizeof(u64));
		len = sizeof(u64);
	}
	seq = cpu_to_be64(seq);
	memcpy(info + ivsize - len, &seq, len);
	crypto_xor(info, ctx->salt, ivsize);
}

static int seqiv_givencrypt(struct skcipher_givcrypt_request *req)
{
	struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req);
	struct seqiv_ctx *ctx = crypto_ablkcipher_ctx(geniv);
	struct ablkcipher_request *subreq = skcipher_givcrypt_reqctx(req);
	crypto_completion_t complete;
	void *data;
	u8 *info;
	unsigned int ivsize;
	int err;

	ablkcipher_request_set_tfm(subreq, skcipher_geniv_cipher(geniv));

	complete = req->creq.base.complete;
	data = req->creq.base.data;
	info = req->creq.info;

	ivsize = crypto_ablkcipher_ivsize(geniv);

	if (unlikely(!IS_ALIGNED((unsigned long)info,
				 crypto_ablkcipher_alignmask(geniv) + 1))) {
		info = kmalloc(ivsize, req->creq.base.flags &
				       CRYPTO_TFM_REQ_MAY_SLEEP ? GFP_KERNEL:
								  GFP_ATOMIC);
		if (!info)
			return -ENOMEM;

		complete = seqiv_complete;
		data = req;
	}

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

	seqiv_geniv(ctx, info, req->seq, ivsize);
	memcpy(req->giv, info, ivsize);

	err = crypto_ablkcipher_encrypt(subreq);
	if (unlikely(info != req->creq.info))
		seqiv_complete2(req, err);
	return err;
}

static int seqiv_aead_givencrypt(struct aead_givcrypt_request *req)
{
	struct crypto_aead *geniv = aead_givcrypt_reqtfm(req);
	struct seqiv_ctx *ctx = crypto_aead_ctx(geniv);
	struct aead_request *areq = &req->areq;
	struct aead_request *subreq = aead_givcrypt_reqctx(req);
	crypto_completion_t complete;
	void *data;
	u8 *info;
	unsigned int ivsize;
	int err;

	aead_request_set_tfm(subreq, aead_geniv_base(geniv));

	complete = areq->base.complete;
	data = areq->base.data;
	info = areq->iv;

	ivsize = crypto_aead_ivsize(geniv);

	if (unlikely(!IS_ALIGNED((unsigned long)info,
				 crypto_aead_alignmask(geniv) + 1))) {
		info = kmalloc(ivsize, areq->base.flags &
				       CRYPTO_TFM_REQ_MAY_SLEEP ? GFP_KERNEL:
								  GFP_ATOMIC);
		if (!info)
			return -ENOMEM;

		complete = seqiv_aead_complete;
		data = req;
	}

	aead_request_set_callback(subreq, areq->base.flags, complete, data);
	aead_request_set_crypt(subreq, areq->src, areq->dst, areq->cryptlen,
			       info);
	aead_request_set_assoc(subreq, areq->assoc, areq->assoclen);

	seqiv_geniv(ctx, info, req->seq, ivsize);
	memcpy(req->giv, info, ivsize);

	err = crypto_aead_encrypt(subreq);
	if (unlikely(info != areq->iv))
		seqiv_aead_complete2(req, err);
	return err;
}

static int seqiv_givencrypt_first(struct skcipher_givcrypt_request *req)
{
	struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req);
	struct seqiv_ctx *ctx = crypto_ablkcipher_ctx(geniv);

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

	crypto_ablkcipher_crt(geniv)->givencrypt = seqiv_givencrypt;
	get_random_bytes(ctx->salt, crypto_ablkcipher_ivsize(geniv));

unlock:
	spin_unlock_bh(&ctx->lock);

	return seqiv_givencrypt(req);
}

static int seqiv_aead_givencrypt_first(struct aead_givcrypt_request *req)
{
	struct crypto_aead *geniv = aead_givcrypt_reqtfm(req);
	struct seqiv_ctx *ctx = crypto_aead_ctx(geniv);

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

	crypto_aead_crt(geniv)->givencrypt = seqiv_aead_givencrypt;
	get_random_bytes(ctx->salt, crypto_aead_ivsize(geniv));

unlock:
	spin_unlock_bh(&ctx->lock);

	return seqiv_aead_givencrypt(req);
}

static int seqiv_init(struct crypto_tfm *tfm)
{
	struct crypto_ablkcipher *geniv = __crypto_ablkcipher_cast(tfm);
	struct seqiv_ctx *ctx = crypto_ablkcipher_ctx(geniv);

	spin_lock_init(&ctx->lock);

	tfm->crt_ablkcipher.reqsize = sizeof(struct ablkcipher_request);

	return skcipher_geniv_init(tfm);
}

static int seqiv_aead_init(struct crypto_tfm *tfm)
{
	struct crypto_aead *geniv = __crypto_aead_cast(tfm);
	struct seqiv_ctx *ctx = crypto_aead_ctx(geniv);

	spin_lock_init(&ctx->lock);

	tfm->crt_aead.reqsize = sizeof(struct aead_request);

	return aead_geniv_init(tfm);
}

static struct crypto_template seqiv_tmpl;

static struct crypto_instance *seqiv_ablkcipher_alloc(struct rtattr **tb)
{
	struct crypto_instance *inst;

	inst = skcipher_geniv_alloc(&seqiv_tmpl, tb, 0, 0);

	if (IS_ERR(inst))
		goto out;

	inst->alg.cra_ablkcipher.givencrypt = seqiv_givencrypt_first;

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

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

out:
	return inst;
}

static struct crypto_instance *seqiv_aead_alloc(struct rtattr **tb)
{
	struct crypto_instance *inst;

	inst = aead_geniv_alloc(&seqiv_tmpl, tb, 0, 0);

	if (IS_ERR(inst))
		goto out;

	inst->alg.cra_aead.givencrypt = seqiv_aead_givencrypt_first;

	inst->alg.cra_init = seqiv_aead_init;
	inst->alg.cra_exit = aead_geniv_exit;

	inst->alg.cra_ctxsize = inst->alg.cra_aead.ivsize;

out:
	return inst;
}

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

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

	if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & CRYPTO_ALG_TYPE_MASK)
		inst = seqiv_ablkcipher_alloc(tb);
	else
		inst = seqiv_aead_alloc(tb);

	if (IS_ERR(inst))
		goto out;

	inst->alg.cra_alignmask |= __alignof__(u32) - 1;
	inst->alg.cra_ctxsize += sizeof(struct seqiv_ctx);

out:
	return inst;
}

static void seqiv_free(struct crypto_instance *inst)
{
	if ((inst->alg.cra_flags ^ CRYPTO_ALG_TYPE_AEAD) & CRYPTO_ALG_TYPE_MASK)
		skcipher_geniv_free(inst);
	else
		aead_geniv_free(inst);
}

static struct crypto_template seqiv_tmpl = {
	.name = "seqiv",
	.alloc = seqiv_alloc,
	.free = seqiv_free,
	.module = THIS_MODULE,
};

static int __init seqiv_module_init(void)
{
	return crypto_register_template(&seqiv_tmpl);
}

static void __exit seqiv_module_exit(void)
{
	crypto_unregister_template(&seqiv_tmpl);
}

module_init(seqiv_module_init);
module_exit(seqiv_module_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Sequence Number IV Generator");
Commit	Line	Data
0a270321 HX	1	/*
	2	* seqiv: Sequence Number IV Generator
	3	*
	4	* This generator generates an IV based on a sequence number by xoring it
	5	* with a salt. This algorithm is mainly useful for CTR and similar modes.
	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
14df4d80	16	#include <crypto/internal/aead.h>
0a270321 HX	17	#include <crypto/internal/skcipher.h>
	18	#include <linux/err.h>
	19	#include <linux/init.h>
	20	#include <linux/kernel.h>
	21	#include <linux/module.h>
	22	#include <linux/random.h>
	23	#include <linux/spinlock.h>
	24	#include <linux/string.h>
	25
	26	struct seqiv_ctx {
	27	spinlock_t lock;
	28	u8 salt[] __attribute__ ((aligned(__alignof__(u32))));
	29	};
	30
	31	static void seqiv_complete2(struct skcipher_givcrypt_request *req, int err)
	32	{
	33	struct ablkcipher_request *subreq = skcipher_givcrypt_reqctx(req);
	34	struct crypto_ablkcipher *geniv;
	35
	36	if (err == -EINPROGRESS)
	37	return;
	38
	39	if (err)
	40	goto out;
	41
	42	geniv = skcipher_givcrypt_reqtfm(req);
	43	memcpy(req->creq.info, subreq->info, crypto_ablkcipher_ivsize(geniv));
	44
	45	out:
	46	kfree(subreq->info);
	47	}
	48
	49	static void seqiv_complete(struct crypto_async_request *base, int err)
	50	{
	51	struct skcipher_givcrypt_request *req = base->data;
	52
	53	seqiv_complete2(req, err);
	54	skcipher_givcrypt_complete(req, err);
	55	}
	56
14df4d80 HX	57	static void seqiv_aead_complete2(struct aead_givcrypt_request *req, int err)
	58	{
	59	struct aead_request *subreq = aead_givcrypt_reqctx(req);
	60	struct crypto_aead *geniv;
	61
	62	if (err == -EINPROGRESS)
	63	return;
	64
	65	if (err)
	66	goto out;
	67
	68	geniv = aead_givcrypt_reqtfm(req);
	69	memcpy(req->areq.iv, subreq->iv, crypto_aead_ivsize(geniv));
	70
	71	out:
	72	kfree(subreq->iv);
	73	}
	74
	75	static void seqiv_aead_complete(struct crypto_async_request *base, int err)
	76	{
	77	struct aead_givcrypt_request *req = base->data;
	78
	79	seqiv_aead_complete2(req, err);
	80	aead_givcrypt_complete(req, err);
	81	}
	82
	83	static void seqiv_geniv(struct seqiv_ctx ctx, u8 info, u64 seq,
	84	unsigned int ivsize)
	85	{
	86	unsigned int len = ivsize;
	87
	88	if (ivsize > sizeof(u64)) {
	89	memset(info, 0, ivsize - sizeof(u64));
	90	len = sizeof(u64);
	91	}
	92	seq = cpu_to_be64(seq);
	93	memcpy(info + ivsize - len, &seq, len);
	94	crypto_xor(info, ctx->salt, ivsize);
	95	}
	96
0a270321 HX	97	static int seqiv_givencrypt(struct skcipher_givcrypt_request *req)
	98	{
	99	struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req);
	100	struct seqiv_ctx *ctx = crypto_ablkcipher_ctx(geniv);
	101	struct ablkcipher_request *subreq = skcipher_givcrypt_reqctx(req);
	102	crypto_completion_t complete;
	103	void *data;
	104	u8 *info;
0a270321	105	unsigned int ivsize;
0a270321 HX	106	int err;
	107
	108	ablkcipher_request_set_tfm(subreq, skcipher_geniv_cipher(geniv));
	109
	110	complete = req->creq.base.complete;
	111	data = req->creq.base.data;
	112	info = req->creq.info;
	113
	114	ivsize = crypto_ablkcipher_ivsize(geniv);
	115
	116	if (unlikely(!IS_ALIGNED((unsigned long)info,
	117	crypto_ablkcipher_alignmask(geniv) + 1))) {
	118	info = kmalloc(ivsize, req->creq.base.flags &
	119	CRYPTO_TFM_REQ_MAY_SLEEP ? GFP_KERNEL:
	120	GFP_ATOMIC);
	121	if (!info)
	122	return -ENOMEM;
	123
	124	complete = seqiv_complete;
	125	data = req;
	126	}
	127
	128	ablkcipher_request_set_callback(subreq, req->creq.base.flags, complete,
	129	data);
	130	ablkcipher_request_set_crypt(subreq, req->creq.src, req->creq.dst,
	131	req->creq.nbytes, info);
	132
14df4d80	133	seqiv_geniv(ctx, info, req->seq, ivsize);
0a270321 HX	134	memcpy(req->giv, info, ivsize);
	135
	136	err = crypto_ablkcipher_encrypt(subreq);
	137	if (unlikely(info != req->creq.info))
	138	seqiv_complete2(req, err);
	139	return err;
	140	}
	141
14df4d80 HX	142	static int seqiv_aead_givencrypt(struct aead_givcrypt_request *req)
	143	{
	144	struct crypto_aead *geniv = aead_givcrypt_reqtfm(req);
	145	struct seqiv_ctx *ctx = crypto_aead_ctx(geniv);
	146	struct aead_request *areq = &req->areq;
	147	struct aead_request *subreq = aead_givcrypt_reqctx(req);
	148	crypto_completion_t complete;
	149	void *data;
	150	u8 *info;
	151	unsigned int ivsize;
	152	int err;
	153
	154	aead_request_set_tfm(subreq, aead_geniv_base(geniv));
	155
	156	complete = areq->base.complete;
	157	data = areq->base.data;
	158	info = areq->iv;
	159
	160	ivsize = crypto_aead_ivsize(geniv);
	161
	162	if (unlikely(!IS_ALIGNED((unsigned long)info,
	163	crypto_aead_alignmask(geniv) + 1))) {
	164	info = kmalloc(ivsize, areq->base.flags &
	165	CRYPTO_TFM_REQ_MAY_SLEEP ? GFP_KERNEL:
	166	GFP_ATOMIC);
	167	if (!info)
	168	return -ENOMEM;
	169
	170	complete = seqiv_aead_complete;
	171	data = req;
	172	}
	173
	174	aead_request_set_callback(subreq, areq->base.flags, complete, data);
	175	aead_request_set_crypt(subreq, areq->src, areq->dst, areq->cryptlen,
	176	info);
	177	aead_request_set_assoc(subreq, areq->assoc, areq->assoclen);
	178
	179	seqiv_geniv(ctx, info, req->seq, ivsize);
	180	memcpy(req->giv, info, ivsize);
	181
	182	err = crypto_aead_encrypt(subreq);
	183	if (unlikely(info != areq->iv))
	184	seqiv_aead_complete2(req, err);
	185	return err;
	186	}
	187
0a270321 HX	188	static int seqiv_givencrypt_first(struct skcipher_givcrypt_request *req)
	189	{
	190	struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req);
	191	struct seqiv_ctx *ctx = crypto_ablkcipher_ctx(geniv);
	192
	193	spin_lock_bh(&ctx->lock);
	194	if (crypto_ablkcipher_crt(geniv)->givencrypt != seqiv_givencrypt_first)
	195	goto unlock;
	196
	197	crypto_ablkcipher_crt(geniv)->givencrypt = seqiv_givencrypt;
	198	get_random_bytes(ctx->salt, crypto_ablkcipher_ivsize(geniv));
	199
	200	unlock:
	201	spin_unlock_bh(&ctx->lock);
	202
	203	return seqiv_givencrypt(req);
	204	}
	205
14df4d80 HX	206	static int seqiv_aead_givencrypt_first(struct aead_givcrypt_request *req)
	207	{
	208	struct crypto_aead *geniv = aead_givcrypt_reqtfm(req);
	209	struct seqiv_ctx *ctx = crypto_aead_ctx(geniv);
	210
	211	spin_lock_bh(&ctx->lock);
	212	if (crypto_aead_crt(geniv)->givencrypt != seqiv_aead_givencrypt_first)
	213	goto unlock;
	214
	215	crypto_aead_crt(geniv)->givencrypt = seqiv_aead_givencrypt;
	216	get_random_bytes(ctx->salt, crypto_aead_ivsize(geniv));
	217
	218	unlock:
	219	spin_unlock_bh(&ctx->lock);
	220
	221	return seqiv_aead_givencrypt(req);
	222	}
	223
0a270321 HX	224	static int seqiv_init(struct crypto_tfm *tfm)
	225	{
	226	struct crypto_ablkcipher *geniv = __crypto_ablkcipher_cast(tfm);
	227	struct seqiv_ctx *ctx = crypto_ablkcipher_ctx(geniv);
	228
	229	spin_lock_init(&ctx->lock);
	230
	231	tfm->crt_ablkcipher.reqsize = sizeof(struct ablkcipher_request);
	232
	233	return skcipher_geniv_init(tfm);
	234	}
	235
14df4d80 HX	236	static int seqiv_aead_init(struct crypto_tfm *tfm)
	237	{
	238	struct crypto_aead *geniv = __crypto_aead_cast(tfm);
	239	struct seqiv_ctx *ctx = crypto_aead_ctx(geniv);
	240
	241	spin_lock_init(&ctx->lock);
	242
	243	tfm->crt_aead.reqsize = sizeof(struct aead_request);
	244
	245	return aead_geniv_init(tfm);
	246	}
	247
0a270321 HX	248	static struct crypto_template seqiv_tmpl;
0a270321 HX	249
14df4d80	250	static struct crypto_instance seqiv_ablkcipher_alloc(struct rtattr *tb)
0a270321 HX	251	{
	252	struct crypto_instance *inst;
	253
	254	inst = skcipher_geniv_alloc(&seqiv_tmpl, tb, 0, 0);
14df4d80	255
0a270321 HX	256	if (IS_ERR(inst))
	257	goto out;
	258
	259	inst->alg.cra_ablkcipher.givencrypt = seqiv_givencrypt_first;
	260
	261	inst->alg.cra_init = seqiv_init;
	262	inst->alg.cra_exit = skcipher_geniv_exit;
	263
0a270321 HX	264	inst->alg.cra_ctxsize += inst->alg.cra_ablkcipher.ivsize;
	265
	266	out:
	267	return inst;
	268	}
	269
14df4d80 HX	270	static struct crypto_instance seqiv_aead_alloc(struct rtattr *tb)
	271	{
	272	struct crypto_instance *inst;
	273
	274	inst = aead_geniv_alloc(&seqiv_tmpl, tb, 0, 0);
	275
	276	if (IS_ERR(inst))
	277	goto out;
	278
	279	inst->alg.cra_aead.givencrypt = seqiv_aead_givencrypt_first;
	280
	281	inst->alg.cra_init = seqiv_aead_init;
	282	inst->alg.cra_exit = aead_geniv_exit;
	283
	284	inst->alg.cra_ctxsize = inst->alg.cra_aead.ivsize;
	285
	286	out:
	287	return inst;
	288	}
	289
	290	static struct crypto_instance seqiv_alloc(struct rtattr *tb)
	291	{
	292	struct crypto_attr_type *algt;
	293	struct crypto_instance *inst;
	294	int err;
	295
	296	algt = crypto_get_attr_type(tb);
	297	err = PTR_ERR(algt);
	298	if (IS_ERR(algt))
	299	return ERR_PTR(err);
	300
	301	if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & CRYPTO_ALG_TYPE_MASK)
	302	inst = seqiv_ablkcipher_alloc(tb);
	303	else
	304	inst = seqiv_aead_alloc(tb);
	305
	306	if (IS_ERR(inst))
	307	goto out;
	308
	309	inst->alg.cra_alignmask \|= __alignof__(u32) - 1;
	310	inst->alg.cra_ctxsize += sizeof(struct seqiv_ctx);
	311
	312	out:
	313	return inst;
	314	}
	315
	316	static void seqiv_free(struct crypto_instance *inst)
	317	{
	318	if ((inst->alg.cra_flags ^ CRYPTO_ALG_TYPE_AEAD) & CRYPTO_ALG_TYPE_MASK)
	319	skcipher_geniv_free(inst);
	320	else
	321	aead_geniv_free(inst);
	322	}
	323
0a270321 HX	324	static struct crypto_template seqiv_tmpl = {
	325	.name = "seqiv",
	326	.alloc = seqiv_alloc,
14df4d80	327	.free = seqiv_free,
0a270321 HX	328	.module = THIS_MODULE,
	329	};
	330
	331	static int __init seqiv_module_init(void)
	332	{
	333	return crypto_register_template(&seqiv_tmpl);
	334	}
	335
	336	static void __exit seqiv_module_exit(void)
	337	{
	338	crypto_unregister_template(&seqiv_tmpl);
	339	}
	340
	341	module_init(seqiv_module_init);
	342	module_exit(seqiv_module_exit);
	343
	344	MODULE_LICENSE("GPL");
	345	MODULE_DESCRIPTION("Sequence Number IV Generator");