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

/*
 * Cryptographic API.
 *
 * HMAC: Keyed-Hashing for Message Authentication (RFC2104).
 *
 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
 * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
 *
 * The HMAC implementation is derived from USAGI.
 * Copyright (c) 2002 Kazunori Miyazawa <miyazawa@linux-ipv6.org> / USAGI
 *
 * 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/hash.h>
#include <crypto/scatterwalk.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/scatterlist.h>
#include <linux/slab.h>
#include <linux/string.h>

struct hmac_ctx {
	struct shash_desc *desc;
};

static inline void *align_ptr(void *p, unsigned int align)
{
	return (void *)ALIGN((unsigned long)p, align);
}

static inline struct hmac_ctx *hmac_ctx(struct crypto_shash *tfm)
{
	return align_ptr(crypto_shash_ctx_aligned(tfm) +
			 crypto_shash_blocksize(tfm) * 2 +
			 crypto_shash_digestsize(tfm),
			 crypto_tfm_ctx_alignment());
}

static int hmac_setkey(struct crypto_shash *parent,
		       const u8 *inkey, unsigned int keylen)
{
	int bs = crypto_shash_blocksize(parent);
	int ds = crypto_shash_digestsize(parent);
	char *ipad = crypto_shash_ctx_aligned(parent);
	char *opad = ipad + bs;
	char *digest = opad + bs;
	struct hmac_ctx *ctx = align_ptr(digest + ds,
					 crypto_tfm_ctx_alignment());
	unsigned int i;

	if (keylen > bs) {
		int err;

		ctx->desc->flags = crypto_shash_get_flags(parent) &
				   CRYPTO_TFM_REQ_MAY_SLEEP;

		err = crypto_shash_digest(ctx->desc, inkey, keylen, digest);
		if (err)
			return err;

		inkey = digest;
		keylen = ds;
	}

	memcpy(ipad, inkey, keylen);
	memset(ipad + keylen, 0, bs - keylen);
	memcpy(opad, ipad, bs);

	for (i = 0; i < bs; i++) {
		ipad[i] ^= 0x36;
		opad[i] ^= 0x5c;
	}

	return 0;
}

static int hmac_init(struct shash_desc *pdesc)
{
	struct crypto_shash *parent = pdesc->tfm;
	int bs = crypto_shash_blocksize(parent);
	int ds = crypto_shash_digestsize(parent);
	char *ipad = crypto_shash_ctx_aligned(parent);
	struct hmac_ctx *ctx = align_ptr(ipad + bs * 2 + ds,
					 crypto_tfm_ctx_alignment());
	struct shash_desc *desc = shash_desc_ctx(pdesc);

	desc->tfm = ctx->desc->tfm;
	desc->flags = pdesc->flags & CRYPTO_TFM_REQ_MAY_SLEEP;

	return crypto_shash_init(desc) ?:
	       crypto_shash_update(desc, ipad, bs);
}

static int hmac_update(struct shash_desc *pdesc,
		       const u8 *data, unsigned int nbytes)
{
	struct shash_desc *desc = shash_desc_ctx(pdesc);

	desc->flags = pdesc->flags & CRYPTO_TFM_REQ_MAY_SLEEP;

	return crypto_shash_update(desc, data, nbytes);
}

static int hmac_final(struct shash_desc *pdesc, u8 *out)
{
	struct crypto_shash *parent = pdesc->tfm;
	int bs = crypto_shash_blocksize(parent);
	int ds = crypto_shash_digestsize(parent);
	char *opad = crypto_shash_ctx_aligned(parent) + bs;
	char *digest = opad + bs;
	struct shash_desc *desc = shash_desc_ctx(pdesc);

	desc->flags = pdesc->flags & CRYPTO_TFM_REQ_MAY_SLEEP;

	return crypto_shash_final(desc, digest) ?:
	       crypto_shash_digest(desc, opad, bs + ds, out);
}

static int hmac_finup(struct shash_desc *pdesc, const u8 *data,
		      unsigned int nbytes, u8 *out)
{

	struct crypto_shash *parent = pdesc->tfm;
	int bs = crypto_shash_blocksize(parent);
	int ds = crypto_shash_digestsize(parent);
	char *opad = crypto_shash_ctx_aligned(parent) + bs;
	char *digest = opad + bs;
	struct shash_desc *desc = shash_desc_ctx(pdesc);

	desc->flags = pdesc->flags & CRYPTO_TFM_REQ_MAY_SLEEP;

	return crypto_shash_finup(desc, data, nbytes, digest) ?:
	       crypto_shash_digest(desc, opad, bs + ds, out);
}

static int hmac_init_tfm(struct crypto_tfm *tfm)
{
	struct crypto_shash *parent = __crypto_shash_cast(tfm);
	struct crypto_shash *hash;
	struct crypto_instance *inst = (void *)tfm->__crt_alg;
	struct crypto_shash_spawn *spawn = crypto_instance_ctx(inst);
	struct hmac_ctx *ctx = hmac_ctx(parent);

	hash = crypto_spawn_shash(spawn);
	if (IS_ERR(hash))
		return PTR_ERR(hash);

	parent->descsize = sizeof(struct shash_desc) +
			   crypto_shash_descsize(hash);

	ctx->desc = kmalloc(parent->descsize, GFP_KERNEL);
	if (!ctx->desc) {
		crypto_free_shash(hash);
		return -ENOMEM;
	}

	ctx->desc->tfm = hash;
	return 0;
}

static void hmac_exit_tfm(struct crypto_tfm *tfm)
{
	struct hmac_ctx *ctx = hmac_ctx(__crypto_shash_cast(tfm));
	crypto_free_shash(ctx->desc->tfm);
	kzfree(ctx->desc);
}

static int hmac_create(struct crypto_template *tmpl, struct rtattr **tb)
{
	struct shash_instance *inst;
	struct crypto_alg *alg;
	struct shash_alg *salg;
	int err;
	int ds;

	err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SHASH);
	if (err)
		return err;

	salg = shash_attr_alg(tb[1], 0, 0);
	if (IS_ERR(salg))
		return PTR_ERR(salg);

	err = -EINVAL;
	ds = salg->digestsize;
	alg = &salg->base;
	if (ds > alg->cra_blocksize)
		goto out_put_alg;

	inst = shash_alloc_instance("hmac", alg);
	err = PTR_ERR(inst);
	if (IS_ERR(inst))
		goto out_put_alg;

	err = crypto_init_shash_spawn(shash_instance_ctx(inst), salg,
				      shash_crypto_instance(inst));
	if (err)
		goto out_free_inst;

	inst->alg.base.cra_priority = alg->cra_priority;
	inst->alg.base.cra_blocksize = alg->cra_blocksize;
	inst->alg.base.cra_alignmask = alg->cra_alignmask;

	inst->alg.digestsize = ds;

	inst->alg.base.cra_ctxsize = sizeof(struct hmac_ctx) +
				     ALIGN(alg->cra_blocksize * 2 + ds,
					   crypto_tfm_ctx_alignment());

	inst->alg.base.cra_init = hmac_init_tfm;
	inst->alg.base.cra_exit = hmac_exit_tfm;

	inst->alg.init = hmac_init;
	inst->alg.update = hmac_update;
	inst->alg.final = hmac_final;
	inst->alg.finup = hmac_finup;
	inst->alg.setkey = hmac_setkey;

	err = shash_register_instance(tmpl, inst);
	if (err) {
out_free_inst:
		shash_free_instance(shash_crypto_instance(inst));
	}

out_put_alg:
	crypto_mod_put(alg);
	return err;
}

static struct crypto_template hmac_tmpl = {
	.name = "hmac",
	.create = hmac_create,
	.free = shash_free_instance,
	.module = THIS_MODULE,
};

static int __init hmac_module_init(void)
{
	return crypto_register_template(&hmac_tmpl);
}

static void __exit hmac_module_exit(void)
{
	crypto_unregister_template(&hmac_tmpl);
}

module_init(hmac_module_init);
module_exit(hmac_module_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("HMAC hash algorithm");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Cryptographic API.
	3	*
	4	* HMAC: Keyed-Hashing for Message Authentication (RFC2104).
	5	*
	6	* Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
0796ae06	7	* Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
1da177e4 LT	8	*
	9	* The HMAC implementation is derived from USAGI.
	10	* Copyright (c) 2002 Kazunori Miyazawa <miyazawa@linux-ipv6.org> / USAGI
	11	*
	12	* This program is free software; you can redistribute it and/or modify it
	13	* under the terms of the GNU General Public License as published by the Free
0796ae06	14	* Software Foundation; either version 2 of the License, or (at your option)
1da177e4 LT	15	* any later version.
	16	*
	17	*/
0796ae06	18
5f7082ed	19	#include <crypto/internal/hash.h>
b2ab4a57	20	#include <crypto/scatterwalk.h>
0796ae06 HX	21	#include <linux/err.h>
	22	#include <linux/init.h>
	23	#include <linux/kernel.h>
	24	#include <linux/module.h>
378f058c	25	#include <linux/scatterlist.h>
0796ae06 HX	26	#include <linux/slab.h>
	27	#include <linux/string.h>
	28
	29	struct hmac_ctx {
8bd1209c	30	struct shash_desc *desc;
0796ae06	31	};
1da177e4	32
0796ae06 HX	33	static inline void align_ptr(void p, unsigned int align)
	34	{
	35	return (void *)ALIGN((unsigned long)p, align);
	36	}
	37
8bd1209c	38	static inline struct hmac_ctx hmac_ctx(struct crypto_shash tfm)
0796ae06	39	{
8bd1209c HX	40	return align_ptr(crypto_shash_ctx_aligned(tfm) +
	41	crypto_shash_blocksize(tfm) * 2 +
	42	crypto_shash_digestsize(tfm),
	43	crypto_tfm_ctx_alignment());
0796ae06 HX	44	}
0796ae06 HX	45
8bd1209c	46	static int hmac_setkey(struct crypto_shash *parent,
0796ae06 HX	47	const u8 *inkey, unsigned int keylen)
0796ae06 HX	48	{
8bd1209c HX	49	int bs = crypto_shash_blocksize(parent);
	50	int ds = crypto_shash_digestsize(parent);
	51	char *ipad = crypto_shash_ctx_aligned(parent);
0796ae06 HX	52	char *opad = ipad + bs;
0796ae06 HX	53	char *digest = opad + bs;
8bd1209c HX	54	struct hmac_ctx *ctx = align_ptr(digest + ds,
8bd1209c HX	55	crypto_tfm_ctx_alignment());
0796ae06 HX	56	unsigned int i;
	57
	58	if (keylen > bs) {
0796ae06 HX	59	int err;
0796ae06 HX	60
8bd1209c HX	61	ctx->desc->flags = crypto_shash_get_flags(parent) &
8bd1209c HX	62	CRYPTO_TFM_REQ_MAY_SLEEP;
0796ae06	63
8bd1209c	64	err = crypto_shash_digest(ctx->desc, inkey, keylen, digest);
0796ae06 HX	65	if (err)
	66	return err;
	67
	68	inkey = digest;
	69	keylen = ds;
	70	}
	71
	72	memcpy(ipad, inkey, keylen);
	73	memset(ipad + keylen, 0, bs - keylen);
	74	memcpy(opad, ipad, bs);
	75
	76	for (i = 0; i < bs; i++) {
	77	ipad[i] ^= 0x36;
	78	opad[i] ^= 0x5c;
	79	}
	80
	81	return 0;
	82	}
	83
8bd1209c	84	static int hmac_init(struct shash_desc *pdesc)
0796ae06	85	{
8bd1209c HX	86	struct crypto_shash *parent = pdesc->tfm;
	87	int bs = crypto_shash_blocksize(parent);
	88	int ds = crypto_shash_digestsize(parent);
	89	char *ipad = crypto_shash_ctx_aligned(parent);
	90	struct hmac_ctx ctx = align_ptr(ipad + bs 2 + ds,
	91	crypto_tfm_ctx_alignment());
	92	struct shash_desc *desc = shash_desc_ctx(pdesc);
	93
	94	desc->tfm = ctx->desc->tfm;
	95	desc->flags = pdesc->flags & CRYPTO_TFM_REQ_MAY_SLEEP;
	96
	97	return crypto_shash_init(desc) ?:
	98	crypto_shash_update(desc, ipad, bs);
0796ae06 HX	99	}
0796ae06 HX	100
8bd1209c HX	101	static int hmac_update(struct shash_desc *pdesc,
8bd1209c HX	102	const u8 *data, unsigned int nbytes)
0796ae06	103	{
8bd1209c	104	struct shash_desc *desc = shash_desc_ctx(pdesc);
0796ae06	105
8bd1209c	106	desc->flags = pdesc->flags & CRYPTO_TFM_REQ_MAY_SLEEP;
0796ae06	107
8bd1209c	108	return crypto_shash_update(desc, data, nbytes);
0796ae06 HX	109	}
0796ae06 HX	110
8bd1209c	111	static int hmac_final(struct shash_desc pdesc, u8 out)
0796ae06	112	{
8bd1209c HX	113	struct crypto_shash *parent = pdesc->tfm;
	114	int bs = crypto_shash_blocksize(parent);
	115	int ds = crypto_shash_digestsize(parent);
	116	char *opad = crypto_shash_ctx_aligned(parent) + bs;
0796ae06	117	char *digest = opad + bs;
8bd1209c	118	struct shash_desc *desc = shash_desc_ctx(pdesc);
0796ae06	119
8bd1209c	120	desc->flags = pdesc->flags & CRYPTO_TFM_REQ_MAY_SLEEP;
73af07de	121
8bd1209c HX	122	return crypto_shash_final(desc, digest) ?:
8bd1209c HX	123	crypto_shash_digest(desc, opad, bs + ds, out);
0796ae06 HX	124	}
0796ae06 HX	125
8bd1209c HX	126	static int hmac_finup(struct shash_desc pdesc, const u8 data,
8bd1209c HX	127	unsigned int nbytes, u8 *out)
0796ae06	128	{
0796ae06	129
8bd1209c HX	130	struct crypto_shash *parent = pdesc->tfm;
	131	int bs = crypto_shash_blocksize(parent);
	132	int ds = crypto_shash_digestsize(parent);
	133	char *opad = crypto_shash_ctx_aligned(parent) + bs;
	134	char *digest = opad + bs;
	135	struct shash_desc *desc = shash_desc_ctx(pdesc);
78c2f0b8	136
8bd1209c	137	desc->flags = pdesc->flags & CRYPTO_TFM_REQ_MAY_SLEEP;
0796ae06	138
8bd1209c HX	139	return crypto_shash_finup(desc, data, nbytes, digest) ?:
8bd1209c HX	140	crypto_shash_digest(desc, opad, bs + ds, out);
0796ae06 HX	141	}
	142
	143	static int hmac_init_tfm(struct crypto_tfm *tfm)
	144	{
8bd1209c HX	145	struct crypto_shash *parent = __crypto_shash_cast(tfm);
8bd1209c HX	146	struct crypto_shash *hash;
0796ae06	147	struct crypto_instance inst = (void )tfm->__crt_alg;
8bd1209c HX	148	struct crypto_shash_spawn *spawn = crypto_instance_ctx(inst);
8bd1209c HX	149	struct hmac_ctx *ctx = hmac_ctx(parent);
0796ae06	150
8bd1209c	151	hash = crypto_spawn_shash(spawn);
2e306ee0 HX	152	if (IS_ERR(hash))
2e306ee0 HX	153	return PTR_ERR(hash);
0796ae06	154
8bd1209c HX	155	parent->descsize = sizeof(struct shash_desc) +
	156	crypto_shash_descsize(hash);
	157
	158	ctx->desc = kmalloc(parent->descsize, GFP_KERNEL);
	159	if (!ctx->desc) {
	160	crypto_free_shash(hash);
	161	return -ENOMEM;
	162	}
	163
	164	ctx->desc->tfm = hash;
0796ae06 HX	165	return 0;
	166	}
	167
	168	static void hmac_exit_tfm(struct crypto_tfm *tfm)
	169	{
8bd1209c HX	170	struct hmac_ctx *ctx = hmac_ctx(__crypto_shash_cast(tfm));
	171	crypto_free_shash(ctx->desc->tfm);
	172	kzfree(ctx->desc);
0796ae06 HX	173	}
0796ae06 HX	174
8bd1209c	175	static int hmac_create(struct crypto_template tmpl, struct rtattr *tb)
0796ae06	176	{
8bd1209c	177	struct shash_instance *inst;
0796ae06	178	struct crypto_alg *alg;
8bd1209c	179	struct shash_alg *salg;
ebc610e5	180	int err;
ca786dc7	181	int ds;
ebc610e5	182
8bd1209c	183	err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SHASH);
ebc610e5	184	if (err)
8bd1209c HX	185	return err;
	186
	187	salg = shash_attr_alg(tb[1], 0, 0);
	188	if (IS_ERR(salg))
	189	return PTR_ERR(salg);
	190
	191	err = -EINVAL;
	192	ds = salg->digestsize;
	193	alg = &salg->base;
ca786dc7 HX	194	if (ds > alg->cra_blocksize)
	195	goto out_put_alg;
	196
8bd1209c	197	inst = shash_alloc_instance("hmac", alg);
3b3fc322	198	err = PTR_ERR(inst);
0796ae06 HX	199	if (IS_ERR(inst))
	200	goto out_put_alg;
	201
8bd1209c HX	202	err = crypto_init_shash_spawn(shash_instance_ctx(inst), salg,
	203	shash_crypto_instance(inst));
	204	if (err)
	205	goto out_free_inst;
	206
	207	inst->alg.base.cra_priority = alg->cra_priority;
	208	inst->alg.base.cra_blocksize = alg->cra_blocksize;
	209	inst->alg.base.cra_alignmask = alg->cra_alignmask;
0796ae06	210
8bd1209c	211	inst->alg.digestsize = ds;
0796ae06	212
8bd1209c HX	213	inst->alg.base.cra_ctxsize = sizeof(struct hmac_ctx) +
	214	ALIGN(alg->cra_blocksize * 2 + ds,
	215	crypto_tfm_ctx_alignment());
0796ae06	216
8bd1209c HX	217	inst->alg.base.cra_init = hmac_init_tfm;
8bd1209c HX	218	inst->alg.base.cra_exit = hmac_exit_tfm;
0796ae06	219
8bd1209c HX	220	inst->alg.init = hmac_init;
	221	inst->alg.update = hmac_update;
	222	inst->alg.final = hmac_final;
	223	inst->alg.finup = hmac_finup;
	224	inst->alg.setkey = hmac_setkey;
	225
	226	err = shash_register_instance(tmpl, inst);
	227	if (err) {
	228	out_free_inst:
	229	shash_free_instance(shash_crypto_instance(inst));
	230	}
0796ae06 HX	231
	232	out_put_alg:
	233	crypto_mod_put(alg);
8bd1209c	234	return err;
0796ae06 HX	235	}
	236
	237	static struct crypto_template hmac_tmpl = {
	238	.name = "hmac",
8bd1209c HX	239	.create = hmac_create,
8bd1209c HX	240	.free = shash_free_instance,
0796ae06 HX	241	.module = THIS_MODULE,
	242	};
	243
	244	static int __init hmac_module_init(void)
	245	{
	246	return crypto_register_template(&hmac_tmpl);
	247	}
	248
	249	static void __exit hmac_module_exit(void)
	250	{
	251	crypto_unregister_template(&hmac_tmpl);
	252	}
	253
	254	module_init(hmac_module_init);
	255	module_exit(hmac_module_exit);
	256
	257	MODULE_LICENSE("GPL");
	258	MODULE_DESCRIPTION("HMAC hash algorithm");