[mirror_ubuntu-bionic-kernel.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_skcipher *enc;
	struct crypto_skcipher *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_skcipher *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_skcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK);
	crypto_skcipher_set_flags(enc, crypto_aead_get_flags(authenc) &
				       CRYPTO_TFM_REQ_MASK);
	err = crypto_skcipher_setkey(enc, keys.enckey, keys.enckeylen);
	crypto_aead_set_flags(authenc, crypto_skcipher_get_flags(enc) &
				       CRYPTO_TFM_RES_MASK);

out:
	memzero_explicit(&keys, sizeof(keys));
	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);
	SKCIPHER_REQUEST_ON_STACK(skreq, ctx->null);

	skcipher_request_set_tfm(skreq, ctx->null);
	skcipher_request_set_callback(skreq, aead_request_flags(req),
				      NULL, NULL);
	skcipher_request_set_crypt(skreq, req->src, req->dst, req->assoclen,
				   NULL);

	return crypto_skcipher_encrypt(skreq);
}

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_skcipher *enc = ctx->enc;
	unsigned int cryptlen = req->cryptlen;
	struct skcipher_request *skreq = (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);
	}

	skcipher_request_set_tfm(skreq, enc);
	skcipher_request_set_callback(skreq, aead_request_flags(req),
				      crypto_authenc_encrypt_done, req);
	skcipher_request_set_crypt(skreq, src, dst, cryptlen, req->iv);

	err = crypto_skcipher_encrypt(skreq);
	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 skcipher_request *skreq = (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);

	skcipher_request_set_tfm(skreq, ctx->enc);
	skcipher_request_set_callback(skreq, aead_request_flags(req),
				      req->base.complete, req->base.data);
	skcipher_request_set_crypt(skreq, src, dst,
				   req->cryptlen - authsize, req->iv);

	return crypto_skcipher_decrypt(skreq);
}

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_skcipher *enc;
	struct crypto_skcipher *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_skcipher2();
	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 skcipher_request) +
		      crypto_skcipher_reqsize(enc)));

	return 0;

err_free_skcipher:
	crypto_free_skcipher(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_skcipher(ctx->enc);
	crypto_put_default_null_skcipher2();
}

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 skcipher_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_spawn_skcipher_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->base.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->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
		goto err_drop_enc;

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

	inst->alg.ivsize = crypto_skcipher_alg_ivsize(enc);
	inst->alg.chunksize = crypto_skcipher_alg_chunksize(enc);
	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;
7217d49f HX	35	struct crypto_skcipher *enc;
7217d49f HX	36	struct crypto_skcipher *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;
7217d49f	86	struct crypto_skcipher *enc = ctx->enc;
bc6e2bdb MK	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
7217d49f HX	103	crypto_skcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK);
	104	crypto_skcipher_set_flags(enc, crypto_aead_get_flags(authenc) &
	105	CRYPTO_TFM_REQ_MASK);
	106	err = crypto_skcipher_setkey(enc, keys.enckey, keys.enckeylen);
	107	crypto_aead_set_flags(authenc, crypto_skcipher_get_flags(enc) &
3c09f17c HX	108	CRYPTO_TFM_RES_MASK);
	109
	110	out:
a4a906df	111	memzero_explicit(&keys, sizeof(keys));
3c09f17c	112	return err;
e236d4a8 HX	113
	114	badkey:
	115	crypto_aead_set_flags(authenc, CRYPTO_TFM_RES_BAD_KEY_LEN);
	116	goto out;
3c09f17c HX	117	}
3c09f17c HX	118
cbdcf80d SK	119	static void authenc_geniv_ahash_done(struct crypto_async_request *areq, int err)
	120	{
	121	struct aead_request *req = areq->data;
	122	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
92d95ba9 HX	123	struct aead_instance *inst = aead_alg_instance(authenc);
92d95ba9 HX	124	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
cbdcf80d	125	struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
92d95ba9	126	struct ahash_request ahreq = (void )(areq_ctx->tail + ictx->reqoff);
cbdcf80d SK	127
	128	if (err)
	129	goto out;
	130
92d95ba9 HX	131	scatterwalk_map_and_copy(ahreq->result, req->dst,
92d95ba9 HX	132	req->assoclen + req->cryptlen,
cbdcf80d SK	133	crypto_aead_authsize(authenc), 1);
	134
	135	out:
	136	aead_request_complete(req, err);
	137	}
	138
92d95ba9	139	static int crypto_authenc_genicv(struct aead_request *req, unsigned int flags)
cbdcf80d SK	140	{
cbdcf80d SK	141	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
92d95ba9	142	struct aead_instance *inst = aead_alg_instance(authenc);
cbdcf80d	143	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
92d95ba9	144	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
cbdcf80d SK	145	struct crypto_ahash *auth = ctx->auth;
cbdcf80d SK	146	struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
92d95ba9	147	struct ahash_request ahreq = (void )(areq_ctx->tail + ictx->reqoff);
cbdcf80d SK	148	u8 *hash = areq_ctx->tail;
cbdcf80d SK	149	int err;
3c09f17c	150
cbdcf80d SK	151	hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
	152	crypto_ahash_alignmask(auth) + 1);
	153
	154	ahash_request_set_tfm(ahreq, auth);
92d95ba9 HX	155	ahash_request_set_crypt(ahreq, req->dst, hash,
	156	req->assoclen + req->cryptlen);
	157	ahash_request_set_callback(ahreq, flags,
	158	authenc_geniv_ahash_done, req);
cbdcf80d SK	159
cbdcf80d SK	160	err = crypto_ahash_digest(ahreq);
3c09f17c	161	if (err)
92d95ba9	162	return err;
3c09f17c	163
92d95ba9	164	scatterwalk_map_and_copy(hash, req->dst, req->assoclen + req->cryptlen,
7ba683a6	165	crypto_aead_authsize(authenc), 1);
92d95ba9	166
3c09f17c HX	167	return 0;
	168	}
	169
	170	static void crypto_authenc_encrypt_done(struct crypto_async_request *req,
	171	int err)
	172	{
a697690b HX	173	struct aead_request *areq = req->data;
a697690b HX	174
92d95ba9 HX	175	if (err)
92d95ba9 HX	176	goto out;
e56dd564	177
92d95ba9	178	err = crypto_authenc_genicv(areq, 0);
3c09f17c	179
92d95ba9	180	out:
180ce7e8	181	authenc_request_complete(areq, err);
3c09f17c HX	182	}
3c09f17c HX	183
92d95ba9 HX	184	static int crypto_authenc_copy_assoc(struct aead_request *req)
	185	{
	186	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
	187	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
7217d49f	188	SKCIPHER_REQUEST_ON_STACK(skreq, ctx->null);
92d95ba9	189
7217d49f HX	190	skcipher_request_set_tfm(skreq, ctx->null);
	191	skcipher_request_set_callback(skreq, aead_request_flags(req),
	192	NULL, NULL);
	193	skcipher_request_set_crypt(skreq, req->src, req->dst, req->assoclen,
	194	NULL);
	195
	196	return crypto_skcipher_encrypt(skreq);
92d95ba9 HX	197	}
92d95ba9 HX	198
3c09f17c HX	199	static int crypto_authenc_encrypt(struct aead_request *req)
	200	{
	201	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
92d95ba9	202	struct aead_instance *inst = aead_alg_instance(authenc);
3c09f17c	203	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
92d95ba9	204	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
50beceba	205	struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
7217d49f	206	struct crypto_skcipher *enc = ctx->enc;
e56dd564	207	unsigned int cryptlen = req->cryptlen;
7217d49f HX	208	struct skcipher_request skreq = (void )(areq_ctx->tail +
7217d49f HX	209	ictx->reqoff);
92d95ba9	210	struct scatterlist src, dst;
3c09f17c HX	211	int err;
3c09f17c HX	212
92d95ba9 HX	213	src = scatterwalk_ffwd(areq_ctx->src, req->src, req->assoclen);
	214	dst = src;
	215
	216	if (req->src != req->dst) {
	217	err = crypto_authenc_copy_assoc(req);
	218	if (err)
	219	return err;
	220
92d95ba9 HX	221	dst = scatterwalk_ffwd(areq_ctx->dst, req->dst, req->assoclen);
	222	}
	223
7217d49f HX	224	skcipher_request_set_tfm(skreq, enc);
	225	skcipher_request_set_callback(skreq, aead_request_flags(req),
	226	crypto_authenc_encrypt_done, req);
	227	skcipher_request_set_crypt(skreq, src, dst, cryptlen, req->iv);
3c09f17c	228
7217d49f	229	err = crypto_skcipher_encrypt(skreq);
3c09f17c HX	230	if (err)
	231	return err;
	232
92d95ba9	233	return crypto_authenc_genicv(req, aead_request_flags(req));
e56dd564 HX	234	}
e56dd564 HX	235
92d95ba9 HX	236	static int crypto_authenc_decrypt_tail(struct aead_request *req,
92d95ba9 HX	237	unsigned int flags)
e56dd564	238	{
92d95ba9 HX	239	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
	240	struct aead_instance *inst = aead_alg_instance(authenc);
	241	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
	242	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
	243	struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
	244	struct ahash_request ahreq = (void )(areq_ctx->tail + ictx->reqoff);
7217d49f HX	245	struct skcipher_request skreq = (void )(areq_ctx->tail +
7217d49f HX	246	ictx->reqoff);
92d95ba9 HX	247	unsigned int authsize = crypto_aead_authsize(authenc);
	248	u8 *ihash = ahreq->result + authsize;
	249	struct scatterlist src, dst;
e56dd564	250
92d95ba9	251	scatterwalk_map_and_copy(ihash, req->src, ahreq->nbytes, authsize, 0);
e56dd564	252
92d95ba9 HX	253	if (crypto_memneq(ihash, ahreq->result, authsize))
92d95ba9 HX	254	return -EBADMSG;
e56dd564	255
92d95ba9 HX	256	src = scatterwalk_ffwd(areq_ctx->src, req->src, req->assoclen);
92d95ba9 HX	257	dst = src;
e56dd564	258
c34252fd	259	if (req->src != req->dst)
92d95ba9	260	dst = scatterwalk_ffwd(areq_ctx->dst, req->dst, req->assoclen);
e56dd564	261
7217d49f HX	262	skcipher_request_set_tfm(skreq, ctx->enc);
	263	skcipher_request_set_callback(skreq, aead_request_flags(req),
	264	req->base.complete, req->base.data);
	265	skcipher_request_set_crypt(skreq, src, dst,
	266	req->cryptlen - authsize, req->iv);
3c09f17c	267
7217d49f	268	return crypto_skcipher_decrypt(skreq);
3c09f17c HX	269	}
3c09f17c HX	270
92d95ba9 HX	271	static void authenc_verify_ahash_done(struct crypto_async_request *areq,
92d95ba9 HX	272	int err)
3c09f17c	273	{
92d95ba9	274	struct aead_request *req = areq->data;
cbdcf80d	275
92d95ba9 HX	276	if (err)
92d95ba9 HX	277	goto out;
e56dd564	278
92d95ba9	279	err = crypto_authenc_decrypt_tail(req, 0);
cbdcf80d	280
92d95ba9 HX	281	out:
92d95ba9 HX	282	authenc_request_complete(req, err);
3c09f17c HX	283	}
	284
	285	static int crypto_authenc_decrypt(struct aead_request *req)
	286	{
	287	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
481f34ae	288	unsigned int authsize = crypto_aead_authsize(authenc);
92d95ba9 HX	289	struct aead_instance *inst = aead_alg_instance(authenc);
	290	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
	291	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
	292	struct crypto_ahash *auth = ctx->auth;
	293	struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
	294	struct ahash_request ahreq = (void )(areq_ctx->tail + ictx->reqoff);
	295	u8 *hash = areq_ctx->tail;
3c09f17c HX	296	int err;
3c09f17c HX	297
92d95ba9 HX	298	hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
92d95ba9 HX	299	crypto_ahash_alignmask(auth) + 1);
481f34ae	300
92d95ba9 HX	301	ahash_request_set_tfm(ahreq, auth);
	302	ahash_request_set_crypt(ahreq, req->src, hash,
	303	req->assoclen + req->cryptlen - authsize);
	304	ahash_request_set_callback(ahreq, aead_request_flags(req),
	305	authenc_verify_ahash_done, req);
	306
	307	err = crypto_ahash_digest(ahreq);
3c09f17c HX	308	if (err)
	309	return err;
	310
92d95ba9	311	return crypto_authenc_decrypt_tail(req, aead_request_flags(req));
3c09f17c HX	312	}
3c09f17c HX	313
92d95ba9	314	static int crypto_authenc_init_tfm(struct crypto_aead *tfm)
3c09f17c	315	{
92d95ba9 HX	316	struct aead_instance *inst = aead_alg_instance(tfm);
	317	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
	318	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(tfm);
cbdcf80d	319	struct crypto_ahash *auth;
7217d49f HX	320	struct crypto_skcipher *enc;
7217d49f HX	321	struct crypto_skcipher *null;
3c09f17c HX	322	int err;
3c09f17c HX	323
cbdcf80d	324	auth = crypto_spawn_ahash(&ictx->auth);
3c09f17c HX	325	if (IS_ERR(auth))
	326	return PTR_ERR(auth);
	327
60425a8b	328	enc = crypto_spawn_skcipher(&ictx->enc);
3c09f17c HX	329	err = PTR_ERR(enc);
3c09f17c HX	330	if (IS_ERR(enc))
cbdcf80d	331	goto err_free_ahash;
3c09f17c	332
7217d49f	333	null = crypto_get_default_null_skcipher2();
92d95ba9 HX	334	err = PTR_ERR(null);
	335	if (IS_ERR(null))
	336	goto err_free_skcipher;
	337
3c09f17c HX	338	ctx->auth = auth;
3c09f17c HX	339	ctx->enc = enc;
92d95ba9	340	ctx->null = null;
f3542e6d	341
92d95ba9 HX	342	crypto_aead_set_reqsize(
92d95ba9 HX	343	tfm,
25df9194	344	sizeof(struct authenc_request_ctx) +
92d95ba9	345	ictx->reqoff +
25df9194	346	max_t(unsigned int,
92d95ba9 HX	347	crypto_ahash_reqsize(auth) +
92d95ba9 HX	348	sizeof(struct ahash_request),
7217d49f HX	349	sizeof(struct skcipher_request) +
7217d49f HX	350	crypto_skcipher_reqsize(enc)));
3c09f17c HX	351
	352	return 0;
	353
92d95ba9	354	err_free_skcipher:
7217d49f	355	crypto_free_skcipher(enc);
cbdcf80d SK	356	err_free_ahash:
cbdcf80d SK	357	crypto_free_ahash(auth);
3c09f17c HX	358	return err;
	359	}
	360
92d95ba9	361	static void crypto_authenc_exit_tfm(struct crypto_aead *tfm)
3c09f17c	362	{
92d95ba9	363	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(tfm);
3c09f17c	364
cbdcf80d	365	crypto_free_ahash(ctx->auth);
7217d49f HX	366	crypto_free_skcipher(ctx->enc);
7217d49f HX	367	crypto_put_default_null_skcipher2();
3c09f17c HX	368	}
3c09f17c HX	369
92d95ba9 HX	370	static void crypto_authenc_free(struct aead_instance *inst)
	371	{
	372	struct authenc_instance_ctx *ctx = aead_instance_ctx(inst);
	373
	374	crypto_drop_skcipher(&ctx->enc);
	375	crypto_drop_ahash(&ctx->auth);
	376	kfree(inst);
	377	}
	378
	379	static int crypto_authenc_create(struct crypto_template *tmpl,
	380	struct rtattr **tb)
3c09f17c	381	{
9ffde35a	382	struct crypto_attr_type *algt;
92d95ba9	383	struct aead_instance *inst;
cbdcf80d SK	384	struct hash_alg_common *auth;
cbdcf80d SK	385	struct crypto_alg *auth_base;
7217d49f	386	struct skcipher_alg *enc;
3c09f17c	387	struct authenc_instance_ctx *ctx;
9ffde35a	388	const char *enc_name;
3c09f17c HX	389	int err;
3c09f17c HX	390
9ffde35a	391	algt = crypto_get_attr_type(tb);
9ffde35a	392	if (IS_ERR(algt))
92d95ba9	393	return PTR_ERR(algt);
3c09f17c	394
5e4b8c1f	395	if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
92d95ba9	396	return -EINVAL;
9ffde35a	397
cbdcf80d	398	auth = ahash_attr_alg(tb[1], CRYPTO_ALG_TYPE_HASH,
927ef32d HX	399	CRYPTO_ALG_TYPE_AHASH_MASK \|
927ef32d HX	400	crypto_requires_sync(algt->type, algt->mask));
3c09f17c	401	if (IS_ERR(auth))
92d95ba9	402	return PTR_ERR(auth);
3c09f17c	403
cbdcf80d SK	404	auth_base = &auth->base;
cbdcf80d SK	405
9ffde35a HX	406	enc_name = crypto_attr_alg_name(tb[2]);
	407	err = PTR_ERR(enc_name);
	408	if (IS_ERR(enc_name))
3c09f17c HX	409	goto out_put_auth;
3c09f17c HX	410
3c09f17c HX	411	inst = kzalloc(sizeof(inst) + sizeof(ctx), GFP_KERNEL);
	412	err = -ENOMEM;
	413	if (!inst)
9ffde35a	414	goto out_put_auth;
3c09f17c	415
92d95ba9	416	ctx = aead_instance_ctx(inst);
3c09f17c	417
92d95ba9 HX	418	err = crypto_init_ahash_spawn(&ctx->auth, auth,
92d95ba9 HX	419	aead_crypto_instance(inst));
3c09f17c HX	420	if (err)
	421	goto err_free_inst;
	422
92d95ba9	423	crypto_set_skcipher_spawn(&ctx->enc, aead_crypto_instance(inst));
a35528ec EB	424	err = crypto_grab_skcipher(&ctx->enc, enc_name, 0,
	425	crypto_requires_sync(algt->type,
	426	algt->mask));
3c09f17c HX	427	if (err)
	428	goto err_drop_auth;
	429
7217d49f	430	enc = crypto_spawn_skcipher_alg(&ctx->enc);
9ffde35a	431
92d95ba9 HX	432	ctx->reqoff = ALIGN(2 * auth->digestsize + auth_base->cra_alignmask,
	433	auth_base->cra_alignmask + 1);
	434
9ffde35a	435	err = -ENAMETOOLONG;
92d95ba9	436	if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
7217d49f HX	437	"authenc(%s,%s)", auth_base->cra_name,
7217d49f HX	438	enc->base.cra_name) >=
9ffde35a HX	439	CRYPTO_MAX_ALG_NAME)
	440	goto err_drop_enc;
	441
92d95ba9	442	if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
cbdcf80d	443	"authenc(%s,%s)", auth_base->cra_driver_name,
7217d49f	444	enc->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
9ffde35a HX	445	goto err_drop_enc;
9ffde35a HX	446
7217d49f HX	447	inst->alg.base.cra_flags = (auth_base->cra_flags \|
	448	enc->base.cra_flags) & CRYPTO_ALG_ASYNC;
	449	inst->alg.base.cra_priority = enc->base.cra_priority * 10 +
92d95ba9	450	auth_base->cra_priority;
7217d49f	451	inst->alg.base.cra_blocksize = enc->base.cra_blocksize;
92d95ba9	452	inst->alg.base.cra_alignmask = auth_base->cra_alignmask \|
7217d49f	453	enc->base.cra_alignmask;
92d95ba9 HX	454	inst->alg.base.cra_ctxsize = sizeof(struct crypto_authenc_ctx);
92d95ba9 HX	455
7217d49f HX	456	inst->alg.ivsize = crypto_skcipher_alg_ivsize(enc);
7217d49f HX	457	inst->alg.chunksize = crypto_skcipher_alg_chunksize(enc);
92d95ba9	458	inst->alg.maxauthsize = auth->digestsize;
3c09f17c	459
92d95ba9 HX	460	inst->alg.init = crypto_authenc_init_tfm;
92d95ba9 HX	461	inst->alg.exit = crypto_authenc_exit_tfm;
3c09f17c	462
92d95ba9 HX	463	inst->alg.setkey = crypto_authenc_setkey;
	464	inst->alg.encrypt = crypto_authenc_encrypt;
	465	inst->alg.decrypt = crypto_authenc_decrypt;
3c09f17c	466
92d95ba9	467	inst->free = crypto_authenc_free;
3c09f17c	468
92d95ba9 HX	469	err = aead_register_instance(tmpl, inst);
	470	if (err)
	471	goto err_drop_enc;
3c09f17c HX	472
3c09f17c HX	473	out:
cbdcf80d	474	crypto_mod_put(auth_base);
92d95ba9	475	return err;
3c09f17c	476
9ffde35a HX	477	err_drop_enc:
9ffde35a HX	478	crypto_drop_skcipher(&ctx->enc);
3c09f17c	479	err_drop_auth:
cbdcf80d	480	crypto_drop_ahash(&ctx->auth);
3c09f17c HX	481	err_free_inst:
3c09f17c HX	482	kfree(inst);
9ffde35a	483	out_put_auth:
3c09f17c HX	484	goto out;
	485	}
	486
3c09f17c HX	487	static struct crypto_template crypto_authenc_tmpl = {
3c09f17c HX	488	.name = "authenc",
92d95ba9	489	.create = crypto_authenc_create,
3c09f17c HX	490	.module = THIS_MODULE,
	491	};
	492
	493	static int __init crypto_authenc_module_init(void)
	494	{
	495	return crypto_register_template(&crypto_authenc_tmpl);
	496	}
	497
	498	static void __exit crypto_authenc_module_exit(void)
	499	{
	500	crypto_unregister_template(&crypto_authenc_tmpl);
	501	}
	502
	503	module_init(crypto_authenc_module_init);
	504	module_exit(crypto_authenc_module_exit);
	505
	506	MODULE_LICENSE("GPL");
	507	MODULE_DESCRIPTION("Simple AEAD wrapper for IPsec");
4943ba16	508	MODULE_ALIAS_CRYPTO("authenc");