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

/*
 * Authenc: Simple AEAD wrapper for IPsec
 *
 * Copyright (c) 2007-2015 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/aead.h>
#include <crypto/internal/hash.h>
#include <crypto/internal/skcipher.h>
#include <crypto/authenc.h>
#include <crypto/null.h>
#include <crypto/scatterwalk.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/rtnetlink.h>
#include <linux/slab.h>
#include <linux/spinlock.h>

struct authenc_instance_ctx {
	struct crypto_ahash_spawn auth;
	struct crypto_skcipher_spawn enc;
	unsigned int reqoff;
};

struct crypto_authenc_ctx {
	struct crypto_ahash *auth;
	struct crypto_ablkcipher *enc;
	struct crypto_blkcipher *null;
};

struct authenc_request_ctx {
	struct scatterlist src[2];
	struct scatterlist dst[2];
	char tail[];
};

static void authenc_request_complete(struct aead_request *req, int err)
{
	if (err != -EINPROGRESS)
		aead_request_complete(req, err);
}

int crypto_authenc_extractkeys(struct crypto_authenc_keys *keys, const u8 *key,
			       unsigned int keylen)
{
	struct rtattr *rta = (struct rtattr *)key;
	struct crypto_authenc_key_param *param;

	if (!RTA_OK(rta, keylen))
		return -EINVAL;
	if (rta->rta_type != CRYPTO_AUTHENC_KEYA_PARAM)
		return -EINVAL;
	if (RTA_PAYLOAD(rta) < sizeof(*param))
		return -EINVAL;

	param = RTA_DATA(rta);
	keys->enckeylen = be32_to_cpu(param->enckeylen);

	key += RTA_ALIGN(rta->rta_len);
	keylen -= RTA_ALIGN(rta->rta_len);

	if (keylen < keys->enckeylen)
		return -EINVAL;

	keys->authkeylen = keylen - keys->enckeylen;
	keys->authkey = key;
	keys->enckey = key + keys->authkeylen;

	return 0;
}
EXPORT_SYMBOL_GPL(crypto_authenc_extractkeys);

static int crypto_authenc_setkey(struct crypto_aead *authenc, const u8 *key,
				 unsigned int keylen)
{
	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
	struct crypto_ahash *auth = ctx->auth;
	struct crypto_ablkcipher *enc = ctx->enc;
	struct crypto_authenc_keys keys;
	int err = -EINVAL;

	if (crypto_authenc_extractkeys(&keys, key, keylen) != 0)
		goto badkey;

	crypto_ahash_clear_flags(auth, CRYPTO_TFM_REQ_MASK);
	crypto_ahash_set_flags(auth, crypto_aead_get_flags(authenc) &
				    CRYPTO_TFM_REQ_MASK);
	err = crypto_ahash_setkey(auth, keys.authkey, keys.authkeylen);
	crypto_aead_set_flags(authenc, crypto_ahash_get_flags(auth) &
				       CRYPTO_TFM_RES_MASK);

	if (err)
		goto out;

	crypto_ablkcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK);
	crypto_ablkcipher_set_flags(enc, crypto_aead_get_flags(authenc) &
					 CRYPTO_TFM_REQ_MASK);
	err = crypto_ablkcipher_setkey(enc, keys.enckey, keys.enckeylen);
	crypto_aead_set_flags(authenc, crypto_ablkcipher_get_flags(enc) &
				       CRYPTO_TFM_RES_MASK);

out:
	return err;

badkey:
	crypto_aead_set_flags(authenc, CRYPTO_TFM_RES_BAD_KEY_LEN);
	goto out;
}

static void authenc_geniv_ahash_done(struct crypto_async_request *areq, int err)
{
	struct aead_request *req = areq->data;
	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
	struct aead_instance *inst = aead_alg_instance(authenc);
	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
	struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ictx->reqoff);

	if (err)
		goto out;

	scatterwalk_map_and_copy(ahreq->result, req->dst,
				 req->assoclen + req->cryptlen,
				 crypto_aead_authsize(authenc), 1);

out:
	aead_request_complete(req, err);
}

static int crypto_authenc_genicv(struct aead_request *req, unsigned int flags)
{
	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
	struct aead_instance *inst = aead_alg_instance(authenc);
	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
	struct crypto_ahash *auth = ctx->auth;
	struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ictx->reqoff);
	u8 *hash = areq_ctx->tail;
	int err;

	hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
			   crypto_ahash_alignmask(auth) + 1);

	ahash_request_set_tfm(ahreq, auth);
	ahash_request_set_crypt(ahreq, req->dst, hash,
				req->assoclen + req->cryptlen);
	ahash_request_set_callback(ahreq, flags,
				   authenc_geniv_ahash_done, req);

	err = crypto_ahash_digest(ahreq);
	if (err)
		return err;

	scatterwalk_map_and_copy(hash, req->dst, req->assoclen + req->cryptlen,
				 crypto_aead_authsize(authenc), 1);

	return 0;
}

static void crypto_authenc_encrypt_done(struct crypto_async_request *req,
					int err)
{
	struct aead_request *areq = req->data;

	if (err)
		goto out;

	err = crypto_authenc_genicv(areq, 0);

out:
	authenc_request_complete(areq, err);
}

static int crypto_authenc_copy_assoc(struct aead_request *req)
{
	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
	struct blkcipher_desc desc = {
		.tfm = ctx->null,
	};

	return crypto_blkcipher_encrypt(&desc, req->dst, req->src,
					req->assoclen);
}

static int crypto_authenc_encrypt(struct aead_request *req)
{
	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
	struct aead_instance *inst = aead_alg_instance(authenc);
	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
	struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
	struct crypto_ablkcipher *enc = ctx->enc;
	unsigned int cryptlen = req->cryptlen;
	struct ablkcipher_request *abreq = (void *)(areq_ctx->tail +
						    ictx->reqoff);
	struct scatterlist *src, *dst;
	int err;

	src = scatterwalk_ffwd(areq_ctx->src, req->src, req->assoclen);
	dst = src;

	if (req->src != req->dst) {
		err = crypto_authenc_copy_assoc(req);
		if (err)
			return err;

		dst = scatterwalk_ffwd(areq_ctx->dst, req->dst, req->assoclen);
	}

	ablkcipher_request_set_tfm(abreq, enc);
	ablkcipher_request_set_callback(abreq, aead_request_flags(req),
					crypto_authenc_encrypt_done, req);
	ablkcipher_request_set_crypt(abreq, src, dst, cryptlen, req->iv);

	err = crypto_ablkcipher_encrypt(abreq);
	if (err)
		return err;

	return crypto_authenc_genicv(req, aead_request_flags(req));
}

static int crypto_authenc_decrypt_tail(struct aead_request *req,
				       unsigned int flags)
{
	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
	struct aead_instance *inst = aead_alg_instance(authenc);
	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
	struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ictx->reqoff);
	struct ablkcipher_request *abreq = (void *)(areq_ctx->tail +
						    ictx->reqoff);
	unsigned int authsize = crypto_aead_authsize(authenc);
	u8 *ihash = ahreq->result + authsize;
	struct scatterlist *src, *dst;

	scatterwalk_map_and_copy(ihash, req->src, ahreq->nbytes, authsize, 0);

	if (crypto_memneq(ihash, ahreq->result, authsize))
		return -EBADMSG;

	src = scatterwalk_ffwd(areq_ctx->src, req->src, req->assoclen);
	dst = src;

	if (req->src != req->dst)
		dst = scatterwalk_ffwd(areq_ctx->dst, req->dst, req->assoclen);

	ablkcipher_request_set_tfm(abreq, ctx->enc);
	ablkcipher_request_set_callback(abreq, aead_request_flags(req),
					req->base.complete, req->base.data);
	ablkcipher_request_set_crypt(abreq, src, dst,
				     req->cryptlen - authsize, req->iv);

	return crypto_ablkcipher_decrypt(abreq);
}

static void authenc_verify_ahash_done(struct crypto_async_request *areq,
				      int err)
{
	struct aead_request *req = areq->data;

	if (err)
		goto out;

	err = crypto_authenc_decrypt_tail(req, 0);

out:
	authenc_request_complete(req, err);
}

static int crypto_authenc_decrypt(struct aead_request *req)
{
	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
	unsigned int authsize = crypto_aead_authsize(authenc);
	struct aead_instance *inst = aead_alg_instance(authenc);
	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
	struct crypto_ahash *auth = ctx->auth;
	struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ictx->reqoff);
	u8 *hash = areq_ctx->tail;
	int err;

	hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
			   crypto_ahash_alignmask(auth) + 1);

	ahash_request_set_tfm(ahreq, auth);
	ahash_request_set_crypt(ahreq, req->src, hash,
				req->assoclen + req->cryptlen - authsize);
	ahash_request_set_callback(ahreq, aead_request_flags(req),
				   authenc_verify_ahash_done, req);

	err = crypto_ahash_digest(ahreq);
	if (err)
		return err;

	return crypto_authenc_decrypt_tail(req, aead_request_flags(req));
}

static int crypto_authenc_init_tfm(struct crypto_aead *tfm)
{
	struct aead_instance *inst = aead_alg_instance(tfm);
	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(tfm);
	struct crypto_ahash *auth;
	struct crypto_ablkcipher *enc;
	struct crypto_blkcipher *null;
	int err;

	auth = crypto_spawn_ahash(&ictx->auth);
	if (IS_ERR(auth))
		return PTR_ERR(auth);

	enc = crypto_spawn_skcipher(&ictx->enc);
	err = PTR_ERR(enc);
	if (IS_ERR(enc))
		goto err_free_ahash;

	null = crypto_get_default_null_skcipher();
	err = PTR_ERR(null);
	if (IS_ERR(null))
		goto err_free_skcipher;

	ctx->auth = auth;
	ctx->enc = enc;
	ctx->null = null;

	crypto_aead_set_reqsize(
		tfm,
		sizeof(struct authenc_request_ctx) +
		ictx->reqoff +
		max_t(unsigned int,
		      crypto_ahash_reqsize(auth) +
		      sizeof(struct ahash_request),
		      sizeof(struct ablkcipher_request) +
		      crypto_ablkcipher_reqsize(enc)));

	return 0;

err_free_skcipher:
	crypto_free_ablkcipher(enc);
err_free_ahash:
	crypto_free_ahash(auth);
	return err;
}

static void crypto_authenc_exit_tfm(struct crypto_aead *tfm)
{
	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(tfm);

	crypto_free_ahash(ctx->auth);
	crypto_free_ablkcipher(ctx->enc);
	crypto_put_default_null_skcipher();
}

static void crypto_authenc_free(struct aead_instance *inst)
{
	struct authenc_instance_ctx *ctx = aead_instance_ctx(inst);

	crypto_drop_skcipher(&ctx->enc);
	crypto_drop_ahash(&ctx->auth);
	kfree(inst);
}

static int crypto_authenc_create(struct crypto_template *tmpl,
				 struct rtattr **tb)
{
	struct crypto_attr_type *algt;
	struct aead_instance *inst;
	struct hash_alg_common *auth;
	struct crypto_alg *auth_base;
	struct crypto_alg *enc;
	struct authenc_instance_ctx *ctx;
	const char *enc_name;
	int err;

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

	if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
		return -EINVAL;

	auth = ahash_attr_alg(tb[1], CRYPTO_ALG_TYPE_HASH,
			      CRYPTO_ALG_TYPE_AHASH_MASK |
			      crypto_requires_sync(algt->type, algt->mask));
	if (IS_ERR(auth))
		return PTR_ERR(auth);

	auth_base = &auth->base;

	enc_name = crypto_attr_alg_name(tb[2]);
	err = PTR_ERR(enc_name);
	if (IS_ERR(enc_name))
		goto out_put_auth;

	inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
	err = -ENOMEM;
	if (!inst)
		goto out_put_auth;

	ctx = aead_instance_ctx(inst);

	err = crypto_init_ahash_spawn(&ctx->auth, auth,
				      aead_crypto_instance(inst));
	if (err)
		goto err_free_inst;

	crypto_set_skcipher_spawn(&ctx->enc, aead_crypto_instance(inst));
	err = crypto_grab_skcipher(&ctx->enc, enc_name, 0,
				   crypto_requires_sync(algt->type,
							algt->mask));
	if (err)
		goto err_drop_auth;

	enc = crypto_skcipher_spawn_alg(&ctx->enc);

	ctx->reqoff = ALIGN(2 * auth->digestsize + auth_base->cra_alignmask,
			    auth_base->cra_alignmask + 1);

	err = -ENAMETOOLONG;
	if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
		     "authenc(%s,%s)", auth_base->cra_name, enc->cra_name) >=
	    CRYPTO_MAX_ALG_NAME)
		goto err_drop_enc;

	if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
		     "authenc(%s,%s)", auth_base->cra_driver_name,
		     enc->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
		goto err_drop_enc;

	inst->alg.base.cra_flags = (auth_base->cra_flags | enc->cra_flags) &
				   CRYPTO_ALG_ASYNC;
	inst->alg.base.cra_priority = enc->cra_priority * 10 +
				      auth_base->cra_priority;
	inst->alg.base.cra_blocksize = enc->cra_blocksize;
	inst->alg.base.cra_alignmask = auth_base->cra_alignmask |
				       enc->cra_alignmask;
	inst->alg.base.cra_ctxsize = sizeof(struct crypto_authenc_ctx);

	inst->alg.ivsize = enc->cra_ablkcipher.ivsize;
	inst->alg.maxauthsize = auth->digestsize;

	inst->alg.init = crypto_authenc_init_tfm;
	inst->alg.exit = crypto_authenc_exit_tfm;

	inst->alg.setkey = crypto_authenc_setkey;
	inst->alg.encrypt = crypto_authenc_encrypt;
	inst->alg.decrypt = crypto_authenc_decrypt;

	inst->free = crypto_authenc_free;

	err = aead_register_instance(tmpl, inst);
	if (err)
		goto err_drop_enc;

out:
	crypto_mod_put(auth_base);
	return err;

err_drop_enc:
	crypto_drop_skcipher(&ctx->enc);
err_drop_auth:
	crypto_drop_ahash(&ctx->auth);
err_free_inst:
	kfree(inst);
out_put_auth:
	goto out;
}

static struct crypto_template crypto_authenc_tmpl = {
	.name = "authenc",
	.create = crypto_authenc_create,
	.module = THIS_MODULE,
};

static int __init crypto_authenc_module_init(void)
{
	return crypto_register_template(&crypto_authenc_tmpl);
}

static void __exit crypto_authenc_module_exit(void)
{
	crypto_unregister_template(&crypto_authenc_tmpl);
}

module_init(crypto_authenc_module_init);
module_exit(crypto_authenc_module_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Simple AEAD wrapper for IPsec");
MODULE_ALIAS_CRYPTO("authenc");
Commit	Line	Data
3c09f17c HX	1	/*
	2	* Authenc: Simple AEAD wrapper for IPsec
	3	*
92d95ba9	4	* Copyright (c) 2007-2015 Herbert Xu <herbert@gondor.apana.org.au>
3c09f17c HX	5	*
	6	* This program is free software; you can redistribute it and/or modify it
	7	* under the terms of the GNU General Public License as published by the Free
	8	* Software Foundation; either version 2 of the License, or (at your option)
	9	* any later version.
	10	*
	11	*/
	12
68acbf84	13	#include <crypto/internal/aead.h>
5f7082ed	14	#include <crypto/internal/hash.h>
9ffde35a	15	#include <crypto/internal/skcipher.h>
e236d4a8	16	#include <crypto/authenc.h>
92d95ba9	17	#include <crypto/null.h>
42c271c6	18	#include <crypto/scatterwalk.h>
3c09f17c HX	19	#include <linux/err.h>
	20	#include <linux/init.h>
	21	#include <linux/kernel.h>
	22	#include <linux/module.h>
e236d4a8	23	#include <linux/rtnetlink.h>
3c09f17c HX	24	#include <linux/slab.h>
	25	#include <linux/spinlock.h>
	26
3c09f17c	27	struct authenc_instance_ctx {
cbdcf80d	28	struct crypto_ahash_spawn auth;
9ffde35a	29	struct crypto_skcipher_spawn enc;
92d95ba9	30	unsigned int reqoff;
3c09f17c HX	31	};
	32
	33	struct crypto_authenc_ctx {
cbdcf80d	34	struct crypto_ahash *auth;
3c09f17c	35	struct crypto_ablkcipher *enc;
92d95ba9	36	struct crypto_blkcipher *null;
3c09f17c HX	37	};
3c09f17c HX	38
cbdcf80d	39	struct authenc_request_ctx {
92d95ba9 HX	40	struct scatterlist src[2];
92d95ba9 HX	41	struct scatterlist dst[2];
cbdcf80d SK	42	char tail[];
	43	};
	44
180ce7e8 HX	45	static void authenc_request_complete(struct aead_request *req, int err)
	46	{
	47	if (err != -EINPROGRESS)
	48	aead_request_complete(req, err);
	49	}
	50
bc6e2bdb MK	51	int crypto_authenc_extractkeys(struct crypto_authenc_keys keys, const u8 key,
bc6e2bdb MK	52	unsigned int keylen)
3c09f17c	53	{
bc6e2bdb	54	struct rtattr rta = (struct rtattr )key;
e236d4a8	55	struct crypto_authenc_key_param *param;
3c09f17c	56
12dc5e62	57	if (!RTA_OK(rta, keylen))
bc6e2bdb	58	return -EINVAL;
e236d4a8	59	if (rta->rta_type != CRYPTO_AUTHENC_KEYA_PARAM)
bc6e2bdb	60	return -EINVAL;
e236d4a8	61	if (RTA_PAYLOAD(rta) < sizeof(*param))
bc6e2bdb	62	return -EINVAL;
e236d4a8 HX	63
e236d4a8 HX	64	param = RTA_DATA(rta);
bc6e2bdb	65	keys->enckeylen = be32_to_cpu(param->enckeylen);
e236d4a8 HX	66
	67	key += RTA_ALIGN(rta->rta_len);
	68	keylen -= RTA_ALIGN(rta->rta_len);
	69
bc6e2bdb MK	70	if (keylen < keys->enckeylen)
	71	return -EINVAL;
	72
	73	keys->authkeylen = keylen - keys->enckeylen;
	74	keys->authkey = key;
	75	keys->enckey = key + keys->authkeylen;
e236d4a8	76
bc6e2bdb MK	77	return 0;
	78	}
	79	EXPORT_SYMBOL_GPL(crypto_authenc_extractkeys);
	80
	81	static int crypto_authenc_setkey(struct crypto_aead authenc, const u8 key,
	82	unsigned int keylen)
	83	{
	84	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
	85	struct crypto_ahash *auth = ctx->auth;
	86	struct crypto_ablkcipher *enc = ctx->enc;
	87	struct crypto_authenc_keys keys;
	88	int err = -EINVAL;
	89
	90	if (crypto_authenc_extractkeys(&keys, key, keylen) != 0)
	91	goto badkey;
3c09f17c	92
cbdcf80d SK	93	crypto_ahash_clear_flags(auth, CRYPTO_TFM_REQ_MASK);
cbdcf80d SK	94	crypto_ahash_set_flags(auth, crypto_aead_get_flags(authenc) &
3c09f17c	95	CRYPTO_TFM_REQ_MASK);
bc6e2bdb	96	err = crypto_ahash_setkey(auth, keys.authkey, keys.authkeylen);
cbdcf80d	97	crypto_aead_set_flags(authenc, crypto_ahash_get_flags(auth) &
3c09f17c HX	98	CRYPTO_TFM_RES_MASK);
	99
	100	if (err)
	101	goto out;
	102
	103	crypto_ablkcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK);
	104	crypto_ablkcipher_set_flags(enc, crypto_aead_get_flags(authenc) &
	105	CRYPTO_TFM_REQ_MASK);
bc6e2bdb	106	err = crypto_ablkcipher_setkey(enc, keys.enckey, keys.enckeylen);
3c09f17c HX	107	crypto_aead_set_flags(authenc, crypto_ablkcipher_get_flags(enc) &
	108	CRYPTO_TFM_RES_MASK);
	109
	110	out:
	111	return err;
e236d4a8 HX	112
	113	badkey:
	114	crypto_aead_set_flags(authenc, CRYPTO_TFM_RES_BAD_KEY_LEN);
	115	goto out;
3c09f17c HX	116	}
3c09f17c HX	117
cbdcf80d SK	118	static void authenc_geniv_ahash_done(struct crypto_async_request *areq, int err)
	119	{
	120	struct aead_request *req = areq->data;
	121	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
92d95ba9 HX	122	struct aead_instance *inst = aead_alg_instance(authenc);
92d95ba9 HX	123	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
cbdcf80d	124	struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
92d95ba9	125	struct ahash_request ahreq = (void )(areq_ctx->tail + ictx->reqoff);
cbdcf80d SK	126
	127	if (err)
	128	goto out;
	129
92d95ba9 HX	130	scatterwalk_map_and_copy(ahreq->result, req->dst,
92d95ba9 HX	131	req->assoclen + req->cryptlen,
cbdcf80d SK	132	crypto_aead_authsize(authenc), 1);
	133
	134	out:
	135	aead_request_complete(req, err);
	136	}
	137
92d95ba9	138	static int crypto_authenc_genicv(struct aead_request *req, unsigned int flags)
cbdcf80d SK	139	{
cbdcf80d SK	140	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
92d95ba9	141	struct aead_instance *inst = aead_alg_instance(authenc);
cbdcf80d	142	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
92d95ba9	143	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
cbdcf80d SK	144	struct crypto_ahash *auth = ctx->auth;
cbdcf80d SK	145	struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
92d95ba9	146	struct ahash_request ahreq = (void )(areq_ctx->tail + ictx->reqoff);
cbdcf80d SK	147	u8 *hash = areq_ctx->tail;
cbdcf80d SK	148	int err;
3c09f17c	149
cbdcf80d SK	150	hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
	151	crypto_ahash_alignmask(auth) + 1);
	152
	153	ahash_request_set_tfm(ahreq, auth);
92d95ba9 HX	154	ahash_request_set_crypt(ahreq, req->dst, hash,
	155	req->assoclen + req->cryptlen);
	156	ahash_request_set_callback(ahreq, flags,
	157	authenc_geniv_ahash_done, req);
cbdcf80d SK	158
cbdcf80d SK	159	err = crypto_ahash_digest(ahreq);
3c09f17c	160	if (err)
92d95ba9	161	return err;
3c09f17c	162
92d95ba9	163	scatterwalk_map_and_copy(hash, req->dst, req->assoclen + req->cryptlen,
7ba683a6	164	crypto_aead_authsize(authenc), 1);
92d95ba9	165
3c09f17c HX	166	return 0;
	167	}
	168
	169	static void crypto_authenc_encrypt_done(struct crypto_async_request *req,
	170	int err)
	171	{
a697690b HX	172	struct aead_request *areq = req->data;
a697690b HX	173
92d95ba9 HX	174	if (err)
92d95ba9 HX	175	goto out;
e56dd564	176
92d95ba9	177	err = crypto_authenc_genicv(areq, 0);
3c09f17c	178
92d95ba9	179	out:
180ce7e8	180	authenc_request_complete(areq, err);
3c09f17c HX	181	}
3c09f17c HX	182
92d95ba9 HX	183	static int crypto_authenc_copy_assoc(struct aead_request *req)
	184	{
	185	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
	186	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
	187	struct blkcipher_desc desc = {
	188	.tfm = ctx->null,
	189	};
	190
	191	return crypto_blkcipher_encrypt(&desc, req->dst, req->src,
	192	req->assoclen);
	193	}
	194
3c09f17c HX	195	static int crypto_authenc_encrypt(struct aead_request *req)
	196	{
	197	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
92d95ba9	198	struct aead_instance *inst = aead_alg_instance(authenc);
3c09f17c	199	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
92d95ba9	200	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
50beceba	201	struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
e56dd564	202	struct crypto_ablkcipher *enc = ctx->enc;
e56dd564	203	unsigned int cryptlen = req->cryptlen;
92d95ba9 HX	204	struct ablkcipher_request abreq = (void )(areq_ctx->tail +
	205	ictx->reqoff);
	206	struct scatterlist src, dst;
3c09f17c HX	207	int err;
3c09f17c HX	208
92d95ba9 HX	209	src = scatterwalk_ffwd(areq_ctx->src, req->src, req->assoclen);
	210	dst = src;
	211
	212	if (req->src != req->dst) {
	213	err = crypto_authenc_copy_assoc(req);
	214	if (err)
	215	return err;
	216
92d95ba9 HX	217	dst = scatterwalk_ffwd(areq_ctx->dst, req->dst, req->assoclen);
	218	}
	219
e56dd564	220	ablkcipher_request_set_tfm(abreq, enc);
3c09f17c HX	221	ablkcipher_request_set_callback(abreq, aead_request_flags(req),
3c09f17c HX	222	crypto_authenc_encrypt_done, req);
92d95ba9	223	ablkcipher_request_set_crypt(abreq, src, dst, cryptlen, req->iv);
3c09f17c HX	224
	225	err = crypto_ablkcipher_encrypt(abreq);
	226	if (err)
	227	return err;
	228
92d95ba9	229	return crypto_authenc_genicv(req, aead_request_flags(req));
e56dd564 HX	230	}
e56dd564 HX	231
92d95ba9 HX	232	static int crypto_authenc_decrypt_tail(struct aead_request *req,
92d95ba9 HX	233	unsigned int flags)
e56dd564	234	{
92d95ba9 HX	235	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
	236	struct aead_instance *inst = aead_alg_instance(authenc);
	237	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
	238	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
	239	struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
	240	struct ahash_request ahreq = (void )(areq_ctx->tail + ictx->reqoff);
	241	struct ablkcipher_request abreq = (void )(areq_ctx->tail +
	242	ictx->reqoff);
	243	unsigned int authsize = crypto_aead_authsize(authenc);
	244	u8 *ihash = ahreq->result + authsize;
	245	struct scatterlist src, dst;
e56dd564	246
92d95ba9	247	scatterwalk_map_and_copy(ihash, req->src, ahreq->nbytes, authsize, 0);
e56dd564	248
92d95ba9 HX	249	if (crypto_memneq(ihash, ahreq->result, authsize))
92d95ba9 HX	250	return -EBADMSG;
e56dd564	251
92d95ba9 HX	252	src = scatterwalk_ffwd(areq_ctx->src, req->src, req->assoclen);
92d95ba9 HX	253	dst = src;
e56dd564	254
c34252fd	255	if (req->src != req->dst)
92d95ba9	256	dst = scatterwalk_ffwd(areq_ctx->dst, req->dst, req->assoclen);
e56dd564	257
92d95ba9 HX	258	ablkcipher_request_set_tfm(abreq, ctx->enc);
	259	ablkcipher_request_set_callback(abreq, aead_request_flags(req),
	260	req->base.complete, req->base.data);
	261	ablkcipher_request_set_crypt(abreq, src, dst,
	262	req->cryptlen - authsize, req->iv);
3c09f17c	263
92d95ba9	264	return crypto_ablkcipher_decrypt(abreq);
3c09f17c HX	265	}
3c09f17c HX	266
92d95ba9 HX	267	static void authenc_verify_ahash_done(struct crypto_async_request *areq,
92d95ba9 HX	268	int err)
3c09f17c	269	{
92d95ba9	270	struct aead_request *req = areq->data;
cbdcf80d	271
92d95ba9 HX	272	if (err)
92d95ba9 HX	273	goto out;
e56dd564	274
92d95ba9	275	err = crypto_authenc_decrypt_tail(req, 0);
cbdcf80d	276
92d95ba9 HX	277	out:
92d95ba9 HX	278	authenc_request_complete(req, err);
3c09f17c HX	279	}
	280
	281	static int crypto_authenc_decrypt(struct aead_request *req)
	282	{
	283	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
481f34ae	284	unsigned int authsize = crypto_aead_authsize(authenc);
92d95ba9 HX	285	struct aead_instance *inst = aead_alg_instance(authenc);
	286	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
	287	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
	288	struct crypto_ahash *auth = ctx->auth;
	289	struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
	290	struct ahash_request ahreq = (void )(areq_ctx->tail + ictx->reqoff);
	291	u8 *hash = areq_ctx->tail;
3c09f17c HX	292	int err;
3c09f17c HX	293
92d95ba9 HX	294	hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
92d95ba9 HX	295	crypto_ahash_alignmask(auth) + 1);
481f34ae	296
92d95ba9 HX	297	ahash_request_set_tfm(ahreq, auth);
	298	ahash_request_set_crypt(ahreq, req->src, hash,
	299	req->assoclen + req->cryptlen - authsize);
	300	ahash_request_set_callback(ahreq, aead_request_flags(req),
	301	authenc_verify_ahash_done, req);
	302
	303	err = crypto_ahash_digest(ahreq);
3c09f17c HX	304	if (err)
	305	return err;
	306
92d95ba9	307	return crypto_authenc_decrypt_tail(req, aead_request_flags(req));
3c09f17c HX	308	}
3c09f17c HX	309
92d95ba9	310	static int crypto_authenc_init_tfm(struct crypto_aead *tfm)
3c09f17c	311	{
92d95ba9 HX	312	struct aead_instance *inst = aead_alg_instance(tfm);
	313	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
	314	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(tfm);
cbdcf80d	315	struct crypto_ahash *auth;
3c09f17c	316	struct crypto_ablkcipher *enc;
92d95ba9	317	struct crypto_blkcipher *null;
3c09f17c HX	318	int err;
3c09f17c HX	319
cbdcf80d	320	auth = crypto_spawn_ahash(&ictx->auth);
3c09f17c HX	321	if (IS_ERR(auth))
	322	return PTR_ERR(auth);
	323
9ffde35a	324	enc = crypto_spawn_skcipher(&ictx->enc);
3c09f17c HX	325	err = PTR_ERR(enc);
3c09f17c HX	326	if (IS_ERR(enc))
cbdcf80d	327	goto err_free_ahash;
3c09f17c	328
92d95ba9 HX	329	null = crypto_get_default_null_skcipher();
	330	err = PTR_ERR(null);
	331	if (IS_ERR(null))
	332	goto err_free_skcipher;
	333
3c09f17c HX	334	ctx->auth = auth;
3c09f17c HX	335	ctx->enc = enc;
92d95ba9	336	ctx->null = null;
f3542e6d	337
92d95ba9 HX	338	crypto_aead_set_reqsize(
92d95ba9 HX	339	tfm,
25df9194	340	sizeof(struct authenc_request_ctx) +
92d95ba9	341	ictx->reqoff +
25df9194	342	max_t(unsigned int,
92d95ba9 HX	343	crypto_ahash_reqsize(auth) +
	344	sizeof(struct ahash_request),
	345	sizeof(struct ablkcipher_request) +
	346	crypto_ablkcipher_reqsize(enc)));
3c09f17c HX	347
	348	return 0;
	349
92d95ba9 HX	350	err_free_skcipher:
92d95ba9 HX	351	crypto_free_ablkcipher(enc);
cbdcf80d SK	352	err_free_ahash:
cbdcf80d SK	353	crypto_free_ahash(auth);
3c09f17c HX	354	return err;
	355	}
	356
92d95ba9	357	static void crypto_authenc_exit_tfm(struct crypto_aead *tfm)
3c09f17c	358	{
92d95ba9	359	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(tfm);
3c09f17c	360
cbdcf80d	361	crypto_free_ahash(ctx->auth);
3c09f17c	362	crypto_free_ablkcipher(ctx->enc);
92d95ba9	363	crypto_put_default_null_skcipher();
3c09f17c HX	364	}
3c09f17c HX	365
92d95ba9 HX	366	static void crypto_authenc_free(struct aead_instance *inst)
	367	{
	368	struct authenc_instance_ctx *ctx = aead_instance_ctx(inst);
	369
	370	crypto_drop_skcipher(&ctx->enc);
	371	crypto_drop_ahash(&ctx->auth);
	372	kfree(inst);
	373	}
	374
	375	static int crypto_authenc_create(struct crypto_template *tmpl,
	376	struct rtattr **tb)
3c09f17c	377	{
9ffde35a	378	struct crypto_attr_type *algt;
92d95ba9	379	struct aead_instance *inst;
cbdcf80d SK	380	struct hash_alg_common *auth;
cbdcf80d SK	381	struct crypto_alg *auth_base;
3c09f17c HX	382	struct crypto_alg *enc;
3c09f17c HX	383	struct authenc_instance_ctx *ctx;
9ffde35a	384	const char *enc_name;
3c09f17c HX	385	int err;
3c09f17c HX	386
9ffde35a	387	algt = crypto_get_attr_type(tb);
9ffde35a	388	if (IS_ERR(algt))
92d95ba9	389	return PTR_ERR(algt);
3c09f17c	390
5e4b8c1f	391	if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
92d95ba9	392	return -EINVAL;
9ffde35a	393
cbdcf80d	394	auth = ahash_attr_alg(tb[1], CRYPTO_ALG_TYPE_HASH,
927ef32d HX	395	CRYPTO_ALG_TYPE_AHASH_MASK \|
927ef32d HX	396	crypto_requires_sync(algt->type, algt->mask));
3c09f17c	397	if (IS_ERR(auth))
92d95ba9	398	return PTR_ERR(auth);
3c09f17c	399
cbdcf80d SK	400	auth_base = &auth->base;
cbdcf80d SK	401
9ffde35a HX	402	enc_name = crypto_attr_alg_name(tb[2]);
	403	err = PTR_ERR(enc_name);
	404	if (IS_ERR(enc_name))
3c09f17c HX	405	goto out_put_auth;
3c09f17c HX	406
3c09f17c HX	407	inst = kzalloc(sizeof(inst) + sizeof(ctx), GFP_KERNEL);
	408	err = -ENOMEM;
	409	if (!inst)
9ffde35a	410	goto out_put_auth;
3c09f17c	411
92d95ba9	412	ctx = aead_instance_ctx(inst);
3c09f17c	413
92d95ba9 HX	414	err = crypto_init_ahash_spawn(&ctx->auth, auth,
92d95ba9 HX	415	aead_crypto_instance(inst));
3c09f17c HX	416	if (err)
	417	goto err_free_inst;
	418
92d95ba9	419	crypto_set_skcipher_spawn(&ctx->enc, aead_crypto_instance(inst));
9ffde35a HX	420	err = crypto_grab_skcipher(&ctx->enc, enc_name, 0,
	421	crypto_requires_sync(algt->type,
	422	algt->mask));
3c09f17c HX	423	if (err)
	424	goto err_drop_auth;
	425
9ffde35a HX	426	enc = crypto_skcipher_spawn_alg(&ctx->enc);
9ffde35a HX	427
92d95ba9 HX	428	ctx->reqoff = ALIGN(2 * auth->digestsize + auth_base->cra_alignmask,
	429	auth_base->cra_alignmask + 1);
	430
9ffde35a	431	err = -ENAMETOOLONG;
92d95ba9	432	if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
cbdcf80d	433	"authenc(%s,%s)", auth_base->cra_name, enc->cra_name) >=
9ffde35a HX	434	CRYPTO_MAX_ALG_NAME)
	435	goto err_drop_enc;
	436
92d95ba9	437	if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
cbdcf80d	438	"authenc(%s,%s)", auth_base->cra_driver_name,
9ffde35a HX	439	enc->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
	440	goto err_drop_enc;
	441
927ef32d HX	442	inst->alg.base.cra_flags = (auth_base->cra_flags \| enc->cra_flags) &
927ef32d HX	443	CRYPTO_ALG_ASYNC;
92d95ba9 HX	444	inst->alg.base.cra_priority = enc->cra_priority * 10 +
	445	auth_base->cra_priority;
	446	inst->alg.base.cra_blocksize = enc->cra_blocksize;
	447	inst->alg.base.cra_alignmask = auth_base->cra_alignmask \|
	448	enc->cra_alignmask;
	449	inst->alg.base.cra_ctxsize = sizeof(struct crypto_authenc_ctx);
	450
	451	inst->alg.ivsize = enc->cra_ablkcipher.ivsize;
	452	inst->alg.maxauthsize = auth->digestsize;
3c09f17c	453
92d95ba9 HX	454	inst->alg.init = crypto_authenc_init_tfm;
92d95ba9 HX	455	inst->alg.exit = crypto_authenc_exit_tfm;
3c09f17c	456
92d95ba9 HX	457	inst->alg.setkey = crypto_authenc_setkey;
	458	inst->alg.encrypt = crypto_authenc_encrypt;
	459	inst->alg.decrypt = crypto_authenc_decrypt;
3c09f17c	460
92d95ba9	461	inst->free = crypto_authenc_free;
3c09f17c	462
92d95ba9 HX	463	err = aead_register_instance(tmpl, inst);
	464	if (err)
	465	goto err_drop_enc;
3c09f17c HX	466
3c09f17c HX	467	out:
cbdcf80d	468	crypto_mod_put(auth_base);
92d95ba9	469	return err;
3c09f17c	470
9ffde35a HX	471	err_drop_enc:
9ffde35a HX	472	crypto_drop_skcipher(&ctx->enc);
3c09f17c	473	err_drop_auth:
cbdcf80d	474	crypto_drop_ahash(&ctx->auth);
3c09f17c HX	475	err_free_inst:
3c09f17c HX	476	kfree(inst);
9ffde35a	477	out_put_auth:
3c09f17c HX	478	goto out;
	479	}
	480
3c09f17c HX	481	static struct crypto_template crypto_authenc_tmpl = {
3c09f17c HX	482	.name = "authenc",
92d95ba9	483	.create = crypto_authenc_create,
3c09f17c HX	484	.module = THIS_MODULE,
	485	};
	486
	487	static int __init crypto_authenc_module_init(void)
	488	{
	489	return crypto_register_template(&crypto_authenc_tmpl);
	490	}
	491
	492	static void __exit crypto_authenc_module_exit(void)
	493	{
	494	crypto_unregister_template(&crypto_authenc_tmpl);
	495	}
	496
	497	module_init(crypto_authenc_module_init);
	498	module_exit(crypto_authenc_module_exit);
	499
	500	MODULE_LICENSE("GPL");
	501	MODULE_DESCRIPTION("Simple AEAD wrapper for IPsec");
4943ba16	502	MODULE_ALIAS_CRYPTO("authenc");