[mirror_ubuntu-jammy-kernel.git] / crypto / authenc.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Authenc: Simple AEAD wrapper for IPsec
 *
 * Copyright (c) 2007-2015 Herbert Xu <herbert@gondor.apana.org.au>
 */

#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_sync_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;

	/*
	 * RTA_OK() didn't align the rtattr's payload when validating that it
	 * fits in the buffer.  Yet, the keys should start on the next 4-byte
	 * aligned boundary.  To avoid confusion, require that the rtattr
	 * payload be exactly the param struct, which has a 4-byte aligned size.
	 */
	if (RTA_PAYLOAD(rta) != sizeof(*param))
		return -EINVAL;
	BUILD_BUG_ON(sizeof(*param) % RTA_ALIGNTO);

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

	key += rta->rta_len;
	keylen -= 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 out;

	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;
}

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);
	SYNC_SKCIPHER_REQUEST_ON_STACK(skreq, ctx->null);

	skcipher_request_set_sync_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_sync_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_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 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_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 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);
}

subsys_initcall(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
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
3c09f17c HX	2	/*
	3	* Authenc: Simple AEAD wrapper for IPsec
	4	*
92d95ba9	5	* Copyright (c) 2007-2015 Herbert Xu <herbert@gondor.apana.org.au>
3c09f17c HX	6	*/
3c09f17c HX	7
68acbf84	8	#include <crypto/internal/aead.h>
5f7082ed	9	#include <crypto/internal/hash.h>
9ffde35a	10	#include <crypto/internal/skcipher.h>
e236d4a8	11	#include <crypto/authenc.h>
92d95ba9	12	#include <crypto/null.h>
42c271c6	13	#include <crypto/scatterwalk.h>
3c09f17c HX	14	#include <linux/err.h>
	15	#include <linux/init.h>
	16	#include <linux/kernel.h>
	17	#include <linux/module.h>
e236d4a8	18	#include <linux/rtnetlink.h>
3c09f17c HX	19	#include <linux/slab.h>
	20	#include <linux/spinlock.h>
	21
3c09f17c	22	struct authenc_instance_ctx {
cbdcf80d	23	struct crypto_ahash_spawn auth;
9ffde35a	24	struct crypto_skcipher_spawn enc;
92d95ba9	25	unsigned int reqoff;
3c09f17c HX	26	};
	27
	28	struct crypto_authenc_ctx {
cbdcf80d	29	struct crypto_ahash *auth;
7217d49f	30	struct crypto_skcipher *enc;
8d605398	31	struct crypto_sync_skcipher *null;
3c09f17c HX	32	};
3c09f17c HX	33
cbdcf80d	34	struct authenc_request_ctx {
92d95ba9 HX	35	struct scatterlist src[2];
92d95ba9 HX	36	struct scatterlist dst[2];
cbdcf80d SK	37	char tail[];
	38	};
	39
180ce7e8 HX	40	static void authenc_request_complete(struct aead_request *req, int err)
	41	{
	42	if (err != -EINPROGRESS)
	43	aead_request_complete(req, err);
	44	}
	45
bc6e2bdb MK	46	int crypto_authenc_extractkeys(struct crypto_authenc_keys keys, const u8 key,
bc6e2bdb MK	47	unsigned int keylen)
3c09f17c	48	{
bc6e2bdb	49	struct rtattr rta = (struct rtattr )key;
e236d4a8	50	struct crypto_authenc_key_param *param;
3c09f17c	51
12dc5e62	52	if (!RTA_OK(rta, keylen))
bc6e2bdb	53	return -EINVAL;
e236d4a8	54	if (rta->rta_type != CRYPTO_AUTHENC_KEYA_PARAM)
bc6e2bdb	55	return -EINVAL;
8f9c4693 EB	56
	57	/*
	58	* RTA_OK() didn't align the rtattr's payload when validating that it
	59	* fits in the buffer. Yet, the keys should start on the next 4-byte
	60	* aligned boundary. To avoid confusion, require that the rtattr
	61	* payload be exactly the param struct, which has a 4-byte aligned size.
	62	*/
	63	if (RTA_PAYLOAD(rta) != sizeof(*param))
bc6e2bdb	64	return -EINVAL;
8f9c4693	65	BUILD_BUG_ON(sizeof(*param) % RTA_ALIGNTO);
e236d4a8 HX	66
e236d4a8 HX	67	param = RTA_DATA(rta);
bc6e2bdb	68	keys->enckeylen = be32_to_cpu(param->enckeylen);
e236d4a8	69
8f9c4693 EB	70	key += rta->rta_len;
8f9c4693 EB	71	keylen -= rta->rta_len;
e236d4a8	72
bc6e2bdb MK	73	if (keylen < keys->enckeylen)
	74	return -EINVAL;
	75
	76	keys->authkeylen = keylen - keys->enckeylen;
	77	keys->authkey = key;
	78	keys->enckey = key + keys->authkeylen;
e236d4a8	79
bc6e2bdb MK	80	return 0;
	81	}
	82	EXPORT_SYMBOL_GPL(crypto_authenc_extractkeys);
	83
	84	static int crypto_authenc_setkey(struct crypto_aead authenc, const u8 key,
	85	unsigned int keylen)
	86	{
	87	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
	88	struct crypto_ahash *auth = ctx->auth;
7217d49f	89	struct crypto_skcipher *enc = ctx->enc;
bc6e2bdb MK	90	struct crypto_authenc_keys keys;
	91	int err = -EINVAL;
	92
	93	if (crypto_authenc_extractkeys(&keys, key, keylen) != 0)
674f368a	94	goto out;
3c09f17c	95
cbdcf80d SK	96	crypto_ahash_clear_flags(auth, CRYPTO_TFM_REQ_MASK);
cbdcf80d SK	97	crypto_ahash_set_flags(auth, crypto_aead_get_flags(authenc) &
3c09f17c	98	CRYPTO_TFM_REQ_MASK);
bc6e2bdb	99	err = crypto_ahash_setkey(auth, keys.authkey, keys.authkeylen);
cbdcf80d	100	crypto_aead_set_flags(authenc, crypto_ahash_get_flags(auth) &
3c09f17c HX	101	CRYPTO_TFM_RES_MASK);
	102
	103	if (err)
	104	goto out;
	105
7217d49f HX	106	crypto_skcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK);
	107	crypto_skcipher_set_flags(enc, crypto_aead_get_flags(authenc) &
	108	CRYPTO_TFM_REQ_MASK);
	109	err = crypto_skcipher_setkey(enc, keys.enckey, keys.enckeylen);
	110	crypto_aead_set_flags(authenc, crypto_skcipher_get_flags(enc) &
3c09f17c HX	111	CRYPTO_TFM_RES_MASK);
	112
	113	out:
ad2fdcdf	114	memzero_explicit(&keys, sizeof(keys));
3c09f17c HX	115	return err;
	116	}
	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);
8d605398	187	SYNC_SKCIPHER_REQUEST_ON_STACK(skreq, ctx->null);
92d95ba9	188
8d605398	189	skcipher_request_set_sync_tfm(skreq, ctx->null);
7217d49f HX	190	skcipher_request_set_callback(skreq, aead_request_flags(req),
	191	NULL, NULL);
	192	skcipher_request_set_crypt(skreq, req->src, req->dst, req->assoclen,
	193	NULL);
	194
	195	return crypto_skcipher_encrypt(skreq);
92d95ba9 HX	196	}
92d95ba9 HX	197
3c09f17c HX	198	static int crypto_authenc_encrypt(struct aead_request *req)
	199	{
	200	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
92d95ba9	201	struct aead_instance *inst = aead_alg_instance(authenc);
3c09f17c	202	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
92d95ba9	203	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
50beceba	204	struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
7217d49f	205	struct crypto_skcipher *enc = ctx->enc;
e56dd564	206	unsigned int cryptlen = req->cryptlen;
7217d49f HX	207	struct skcipher_request skreq = (void )(areq_ctx->tail +
7217d49f HX	208	ictx->reqoff);
92d95ba9	209	struct scatterlist src, dst;
3c09f17c HX	210	int err;
3c09f17c HX	211
92d95ba9 HX	212	src = scatterwalk_ffwd(areq_ctx->src, req->src, req->assoclen);
	213	dst = src;
	214
	215	if (req->src != req->dst) {
	216	err = crypto_authenc_copy_assoc(req);
	217	if (err)
	218	return err;
	219
92d95ba9 HX	220	dst = scatterwalk_ffwd(areq_ctx->dst, req->dst, req->assoclen);
	221	}
	222
7217d49f HX	223	skcipher_request_set_tfm(skreq, enc);
	224	skcipher_request_set_callback(skreq, aead_request_flags(req),
	225	crypto_authenc_encrypt_done, req);
	226	skcipher_request_set_crypt(skreq, src, dst, cryptlen, req->iv);
3c09f17c	227
7217d49f	228	err = crypto_skcipher_encrypt(skreq);
3c09f17c HX	229	if (err)
	230	return err;
	231
92d95ba9	232	return crypto_authenc_genicv(req, aead_request_flags(req));
e56dd564 HX	233	}
e56dd564 HX	234
92d95ba9 HX	235	static int crypto_authenc_decrypt_tail(struct aead_request *req,
92d95ba9 HX	236	unsigned int flags)
e56dd564	237	{
92d95ba9 HX	238	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
	239	struct aead_instance *inst = aead_alg_instance(authenc);
	240	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
	241	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
	242	struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
	243	struct ahash_request ahreq = (void )(areq_ctx->tail + ictx->reqoff);
7217d49f HX	244	struct skcipher_request skreq = (void )(areq_ctx->tail +
7217d49f HX	245	ictx->reqoff);
92d95ba9 HX	246	unsigned int authsize = crypto_aead_authsize(authenc);
	247	u8 *ihash = ahreq->result + authsize;
	248	struct scatterlist src, dst;
e56dd564	249
92d95ba9	250	scatterwalk_map_and_copy(ihash, req->src, ahreq->nbytes, authsize, 0);
e56dd564	251
92d95ba9 HX	252	if (crypto_memneq(ihash, ahreq->result, authsize))
92d95ba9 HX	253	return -EBADMSG;
e56dd564	254
92d95ba9 HX	255	src = scatterwalk_ffwd(areq_ctx->src, req->src, req->assoclen);
92d95ba9 HX	256	dst = src;
e56dd564	257
c34252fd	258	if (req->src != req->dst)
92d95ba9	259	dst = scatterwalk_ffwd(areq_ctx->dst, req->dst, req->assoclen);
e56dd564	260
7217d49f HX	261	skcipher_request_set_tfm(skreq, ctx->enc);
	262	skcipher_request_set_callback(skreq, aead_request_flags(req),
	263	req->base.complete, req->base.data);
	264	skcipher_request_set_crypt(skreq, src, dst,
	265	req->cryptlen - authsize, req->iv);
3c09f17c	266
7217d49f	267	return crypto_skcipher_decrypt(skreq);
3c09f17c HX	268	}
3c09f17c HX	269
92d95ba9 HX	270	static void authenc_verify_ahash_done(struct crypto_async_request *areq,
92d95ba9 HX	271	int err)
3c09f17c	272	{
92d95ba9	273	struct aead_request *req = areq->data;
cbdcf80d	274
92d95ba9 HX	275	if (err)
92d95ba9 HX	276	goto out;
e56dd564	277
92d95ba9	278	err = crypto_authenc_decrypt_tail(req, 0);
cbdcf80d	279
92d95ba9 HX	280	out:
92d95ba9 HX	281	authenc_request_complete(req, err);
3c09f17c HX	282	}
	283
	284	static int crypto_authenc_decrypt(struct aead_request *req)
	285	{
	286	struct crypto_aead *authenc = crypto_aead_reqtfm(req);
481f34ae	287	unsigned int authsize = crypto_aead_authsize(authenc);
92d95ba9 HX	288	struct aead_instance *inst = aead_alg_instance(authenc);
	289	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
	290	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
	291	struct crypto_ahash *auth = ctx->auth;
	292	struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
	293	struct ahash_request ahreq = (void )(areq_ctx->tail + ictx->reqoff);
	294	u8 *hash = areq_ctx->tail;
3c09f17c HX	295	int err;
3c09f17c HX	296
92d95ba9 HX	297	hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
92d95ba9 HX	298	crypto_ahash_alignmask(auth) + 1);
481f34ae	299
92d95ba9 HX	300	ahash_request_set_tfm(ahreq, auth);
	301	ahash_request_set_crypt(ahreq, req->src, hash,
	302	req->assoclen + req->cryptlen - authsize);
	303	ahash_request_set_callback(ahreq, aead_request_flags(req),
	304	authenc_verify_ahash_done, req);
	305
	306	err = crypto_ahash_digest(ahreq);
3c09f17c HX	307	if (err)
	308	return err;
	309
92d95ba9	310	return crypto_authenc_decrypt_tail(req, aead_request_flags(req));
3c09f17c HX	311	}
3c09f17c HX	312
92d95ba9	313	static int crypto_authenc_init_tfm(struct crypto_aead *tfm)
3c09f17c	314	{
92d95ba9 HX	315	struct aead_instance *inst = aead_alg_instance(tfm);
	316	struct authenc_instance_ctx *ictx = aead_instance_ctx(inst);
	317	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(tfm);
cbdcf80d	318	struct crypto_ahash *auth;
7217d49f	319	struct crypto_skcipher *enc;
8d605398	320	struct crypto_sync_skcipher *null;
3c09f17c HX	321	int err;
3c09f17c HX	322
cbdcf80d	323	auth = crypto_spawn_ahash(&ictx->auth);
3c09f17c HX	324	if (IS_ERR(auth))
	325	return PTR_ERR(auth);
	326
60425a8b	327	enc = crypto_spawn_skcipher(&ictx->enc);
3c09f17c HX	328	err = PTR_ERR(enc);
3c09f17c HX	329	if (IS_ERR(enc))
cbdcf80d	330	goto err_free_ahash;
3c09f17c	331
3a2d4fb5	332	null = crypto_get_default_null_skcipher();
92d95ba9 HX	333	err = PTR_ERR(null);
	334	if (IS_ERR(null))
	335	goto err_free_skcipher;
	336
3c09f17c HX	337	ctx->auth = auth;
3c09f17c HX	338	ctx->enc = enc;
92d95ba9	339	ctx->null = null;
f3542e6d	340
92d95ba9 HX	341	crypto_aead_set_reqsize(
92d95ba9 HX	342	tfm,
25df9194	343	sizeof(struct authenc_request_ctx) +
92d95ba9	344	ictx->reqoff +
25df9194	345	max_t(unsigned int,
92d95ba9 HX	346	crypto_ahash_reqsize(auth) +
92d95ba9 HX	347	sizeof(struct ahash_request),
7217d49f HX	348	sizeof(struct skcipher_request) +
7217d49f HX	349	crypto_skcipher_reqsize(enc)));
3c09f17c HX	350
	351	return 0;
	352
92d95ba9	353	err_free_skcipher:
7217d49f	354	crypto_free_skcipher(enc);
cbdcf80d SK	355	err_free_ahash:
cbdcf80d SK	356	crypto_free_ahash(auth);
3c09f17c HX	357	return err;
	358	}
	359
92d95ba9	360	static void crypto_authenc_exit_tfm(struct crypto_aead *tfm)
3c09f17c	361	{
92d95ba9	362	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(tfm);
3c09f17c	363
cbdcf80d	364	crypto_free_ahash(ctx->auth);
7217d49f	365	crypto_free_skcipher(ctx->enc);
3a2d4fb5	366	crypto_put_default_null_skcipher();
3c09f17c HX	367	}
3c09f17c HX	368
92d95ba9 HX	369	static void crypto_authenc_free(struct aead_instance *inst)
	370	{
	371	struct authenc_instance_ctx *ctx = aead_instance_ctx(inst);
	372
	373	crypto_drop_skcipher(&ctx->enc);
	374	crypto_drop_ahash(&ctx->auth);
	375	kfree(inst);
	376	}
	377
	378	static int crypto_authenc_create(struct crypto_template *tmpl,
	379	struct rtattr **tb)
3c09f17c	380	{
9ffde35a	381	struct crypto_attr_type *algt;
92d95ba9	382	struct aead_instance *inst;
cbdcf80d SK	383	struct hash_alg_common *auth;
cbdcf80d SK	384	struct crypto_alg *auth_base;
7217d49f	385	struct skcipher_alg *enc;
3c09f17c	386	struct authenc_instance_ctx *ctx;
9ffde35a	387	const char *enc_name;
3c09f17c HX	388	int err;
3c09f17c HX	389
9ffde35a	390	algt = crypto_get_attr_type(tb);
9ffde35a	391	if (IS_ERR(algt))
92d95ba9	392	return PTR_ERR(algt);
3c09f17c	393
5e4b8c1f	394	if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
92d95ba9	395	return -EINVAL;
9ffde35a	396
cbdcf80d	397	auth = ahash_attr_alg(tb[1], CRYPTO_ALG_TYPE_HASH,
927ef32d HX	398	CRYPTO_ALG_TYPE_AHASH_MASK \|
927ef32d HX	399	crypto_requires_sync(algt->type, algt->mask));
3c09f17c	400	if (IS_ERR(auth))
92d95ba9	401	return PTR_ERR(auth);
3c09f17c	402
cbdcf80d SK	403	auth_base = &auth->base;
cbdcf80d SK	404
9ffde35a HX	405	enc_name = crypto_attr_alg_name(tb[2]);
	406	err = PTR_ERR(enc_name);
	407	if (IS_ERR(enc_name))
3c09f17c HX	408	goto out_put_auth;
3c09f17c HX	409
3c09f17c HX	410	inst = kzalloc(sizeof(inst) + sizeof(ctx), GFP_KERNEL);
	411	err = -ENOMEM;
	412	if (!inst)
9ffde35a	413	goto out_put_auth;
3c09f17c	414
92d95ba9	415	ctx = aead_instance_ctx(inst);
3c09f17c	416
92d95ba9 HX	417	err = crypto_init_ahash_spawn(&ctx->auth, auth,
92d95ba9 HX	418	aead_crypto_instance(inst));
3c09f17c HX	419	if (err)
	420	goto err_free_inst;
	421
92d95ba9	422	crypto_set_skcipher_spawn(&ctx->enc, aead_crypto_instance(inst));
a35528ec EB	423	err = crypto_grab_skcipher(&ctx->enc, enc_name, 0,
	424	crypto_requires_sync(algt->type,
	425	algt->mask));
3c09f17c HX	426	if (err)
	427	goto err_drop_auth;
	428
7217d49f	429	enc = crypto_spawn_skcipher_alg(&ctx->enc);
9ffde35a	430
92d95ba9 HX	431	ctx->reqoff = ALIGN(2 * auth->digestsize + auth_base->cra_alignmask,
	432	auth_base->cra_alignmask + 1);
	433
9ffde35a	434	err = -ENAMETOOLONG;
92d95ba9	435	if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
7217d49f HX	436	"authenc(%s,%s)", auth_base->cra_name,
7217d49f HX	437	enc->base.cra_name) >=
9ffde35a HX	438	CRYPTO_MAX_ALG_NAME)
	439	goto err_drop_enc;
	440
92d95ba9	441	if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
cbdcf80d	442	"authenc(%s,%s)", auth_base->cra_driver_name,
7217d49f	443	enc->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
9ffde35a HX	444	goto err_drop_enc;
9ffde35a HX	445
7217d49f HX	446	inst->alg.base.cra_flags = (auth_base->cra_flags \|
	447	enc->base.cra_flags) & CRYPTO_ALG_ASYNC;
	448	inst->alg.base.cra_priority = enc->base.cra_priority * 10 +
92d95ba9	449	auth_base->cra_priority;
7217d49f	450	inst->alg.base.cra_blocksize = enc->base.cra_blocksize;
92d95ba9	451	inst->alg.base.cra_alignmask = auth_base->cra_alignmask \|
7217d49f	452	enc->base.cra_alignmask;
92d95ba9 HX	453	inst->alg.base.cra_ctxsize = sizeof(struct crypto_authenc_ctx);
92d95ba9 HX	454
7217d49f HX	455	inst->alg.ivsize = crypto_skcipher_alg_ivsize(enc);
7217d49f HX	456	inst->alg.chunksize = crypto_skcipher_alg_chunksize(enc);
92d95ba9	457	inst->alg.maxauthsize = auth->digestsize;
3c09f17c	458
92d95ba9 HX	459	inst->alg.init = crypto_authenc_init_tfm;
92d95ba9 HX	460	inst->alg.exit = crypto_authenc_exit_tfm;
3c09f17c	461
92d95ba9 HX	462	inst->alg.setkey = crypto_authenc_setkey;
	463	inst->alg.encrypt = crypto_authenc_encrypt;
	464	inst->alg.decrypt = crypto_authenc_decrypt;
3c09f17c	465
92d95ba9	466	inst->free = crypto_authenc_free;
3c09f17c	467
92d95ba9 HX	468	err = aead_register_instance(tmpl, inst);
	469	if (err)
	470	goto err_drop_enc;
3c09f17c HX	471
3c09f17c HX	472	out:
cbdcf80d	473	crypto_mod_put(auth_base);
92d95ba9	474	return err;
3c09f17c	475
9ffde35a HX	476	err_drop_enc:
9ffde35a HX	477	crypto_drop_skcipher(&ctx->enc);
3c09f17c	478	err_drop_auth:
cbdcf80d	479	crypto_drop_ahash(&ctx->auth);
3c09f17c HX	480	err_free_inst:
3c09f17c HX	481	kfree(inst);
9ffde35a	482	out_put_auth:
3c09f17c HX	483	goto out;
	484	}
	485
3c09f17c HX	486	static struct crypto_template crypto_authenc_tmpl = {
3c09f17c HX	487	.name = "authenc",
92d95ba9	488	.create = crypto_authenc_create,
3c09f17c HX	489	.module = THIS_MODULE,
	490	};
	491
	492	static int __init crypto_authenc_module_init(void)
	493	{
	494	return crypto_register_template(&crypto_authenc_tmpl);
	495	}
	496
	497	static void __exit crypto_authenc_module_exit(void)
	498	{
	499	crypto_unregister_template(&crypto_authenc_tmpl);
	500	}
	501
c4741b23	502	subsys_initcall(crypto_authenc_module_init);
3c09f17c HX	503	module_exit(crypto_authenc_module_exit);
	504
	505	MODULE_LICENSE("GPL");
	506	MODULE_DESCRIPTION("Simple AEAD wrapper for IPsec");
4943ba16	507	MODULE_ALIAS_CRYPTO("authenc");