[mirror_ubuntu-zesty-kernel.git] / crypto / authencesn.c

/*
 * authencesn.c - AEAD wrapper for IPsec with extended sequence numbers,
 *                 derived from authenc.c
 *
 * Copyright (C) 2010 secunet Security Networks AG
 * Copyright (C) 2010 Steffen Klassert <steffen.klassert@secunet.com>
 * Copyright (c) 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_esn_instance_ctx {
	struct crypto_ahash_spawn auth;
	struct crypto_skcipher_spawn enc;
};

struct crypto_authenc_esn_ctx {
	unsigned int reqoff;
	struct crypto_ahash *auth;
	struct crypto_skcipher *enc;
	struct crypto_skcipher *null;
};

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

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

static int crypto_authenc_esn_setauthsize(struct crypto_aead *authenc_esn,
					  unsigned int authsize)
{
	if (authsize > 0 && authsize < 4)
		return -EINVAL;

	return 0;
}

static int crypto_authenc_esn_setkey(struct crypto_aead *authenc_esn, const u8 *key,
				     unsigned int keylen)
{
	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
	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_esn) &
				     CRYPTO_TFM_REQ_MASK);
	err = crypto_ahash_setkey(auth, keys.authkey, keys.authkeylen);
	crypto_aead_set_flags(authenc_esn, 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_esn) &
					 CRYPTO_TFM_REQ_MASK);
	err = crypto_skcipher_setkey(enc, keys.enckey, keys.enckeylen);
	crypto_aead_set_flags(authenc_esn, crypto_skcipher_get_flags(enc) &
					   CRYPTO_TFM_RES_MASK);

out:
	return err;

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

static int crypto_authenc_esn_genicv_tail(struct aead_request *req,
					  unsigned int flags)
{
	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
	struct crypto_ahash *auth = ctx->auth;
	u8 *hash = PTR_ALIGN((u8 *)areq_ctx->tail,
			     crypto_ahash_alignmask(auth) + 1);
	unsigned int authsize = crypto_aead_authsize(authenc_esn);
	unsigned int assoclen = req->assoclen;
	unsigned int cryptlen = req->cryptlen;
	struct scatterlist *dst = req->dst;
	u32 tmp[2];

	/* Move high-order bits of sequence number back. */
	scatterwalk_map_and_copy(tmp, dst, 4, 4, 0);
	scatterwalk_map_and_copy(tmp + 1, dst, assoclen + cryptlen, 4, 0);
	scatterwalk_map_and_copy(tmp, dst, 0, 8, 1);

	scatterwalk_map_and_copy(hash, dst, assoclen + cryptlen, authsize, 1);
	return 0;
}

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

	err = err ?: crypto_authenc_esn_genicv_tail(req, 0);
	aead_request_complete(req, err);
}

static int crypto_authenc_esn_genicv(struct aead_request *req,
				     unsigned int flags)
{
	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
	struct crypto_ahash *auth = ctx->auth;
	u8 *hash = PTR_ALIGN((u8 *)areq_ctx->tail,
			     crypto_ahash_alignmask(auth) + 1);
	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
	unsigned int authsize = crypto_aead_authsize(authenc_esn);
	unsigned int assoclen = req->assoclen;
	unsigned int cryptlen = req->cryptlen;
	struct scatterlist *dst = req->dst;
	u32 tmp[2];

	if (!authsize)
		return 0;

	/* Move high-order bits of sequence number to the end. */
	scatterwalk_map_and_copy(tmp, dst, 0, 8, 0);
	scatterwalk_map_and_copy(tmp, dst, 4, 4, 1);
	scatterwalk_map_and_copy(tmp + 1, dst, assoclen + cryptlen, 4, 1);

	sg_init_table(areq_ctx->dst, 2);
	dst = scatterwalk_ffwd(areq_ctx->dst, dst, 4);

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

	return crypto_ahash_digest(ahreq) ?:
	       crypto_authenc_esn_genicv_tail(req, aead_request_flags(req));
}


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

	if (!err)
		err = crypto_authenc_esn_genicv(areq, 0);

	authenc_esn_request_complete(areq, err);
}

static int crypto_authenc_esn_copy(struct aead_request *req, unsigned int len)
{
	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
	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, len, NULL);

	return crypto_skcipher_encrypt(skreq);
}

static int crypto_authenc_esn_encrypt(struct aead_request *req)
{
	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
	struct skcipher_request *skreq = (void *)(areq_ctx->tail +
						  ctx->reqoff);
	struct crypto_skcipher *enc = ctx->enc;
	unsigned int assoclen = req->assoclen;
	unsigned int cryptlen = req->cryptlen;
	struct scatterlist *src, *dst;
	int err;

	sg_init_table(areq_ctx->src, 2);
	src = scatterwalk_ffwd(areq_ctx->src, req->src, assoclen);
	dst = src;

	if (req->src != req->dst) {
		err = crypto_authenc_esn_copy(req, assoclen);
		if (err)
			return err;

		sg_init_table(areq_ctx->dst, 2);
		dst = scatterwalk_ffwd(areq_ctx->dst, req->dst, assoclen);
	}

	skcipher_request_set_tfm(skreq, enc);
	skcipher_request_set_callback(skreq, aead_request_flags(req),
				      crypto_authenc_esn_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_esn_genicv(req, aead_request_flags(req));
}

static int crypto_authenc_esn_decrypt_tail(struct aead_request *req,
					   unsigned int flags)
{
	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
	unsigned int authsize = crypto_aead_authsize(authenc_esn);
	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
	struct skcipher_request *skreq = (void *)(areq_ctx->tail +
						  ctx->reqoff);
	struct crypto_ahash *auth = ctx->auth;
	u8 *ohash = PTR_ALIGN((u8 *)areq_ctx->tail,
			      crypto_ahash_alignmask(auth) + 1);
	unsigned int cryptlen = req->cryptlen - authsize;
	unsigned int assoclen = req->assoclen;
	struct scatterlist *dst = req->dst;
	u8 *ihash = ohash + crypto_ahash_digestsize(auth);
	u32 tmp[2];

	/* Move high-order bits of sequence number back. */
	scatterwalk_map_and_copy(tmp, dst, 4, 4, 0);
	scatterwalk_map_and_copy(tmp + 1, dst, assoclen + cryptlen, 4, 0);
	scatterwalk_map_and_copy(tmp, dst, 0, 8, 1);

	if (crypto_memneq(ihash, ohash, authsize))
		return -EBADMSG;

	sg_init_table(areq_ctx->dst, 2);
	dst = scatterwalk_ffwd(areq_ctx->dst, dst, assoclen);

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

	return crypto_skcipher_decrypt(skreq);
}

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

	err = err ?: crypto_authenc_esn_decrypt_tail(req, 0);
	aead_request_complete(req, err);
}

static int crypto_authenc_esn_decrypt(struct aead_request *req)
{
	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
	unsigned int authsize = crypto_aead_authsize(authenc_esn);
	struct crypto_ahash *auth = ctx->auth;
	u8 *ohash = PTR_ALIGN((u8 *)areq_ctx->tail,
			      crypto_ahash_alignmask(auth) + 1);
	unsigned int assoclen = req->assoclen;
	unsigned int cryptlen = req->cryptlen;
	u8 *ihash = ohash + crypto_ahash_digestsize(auth);
	struct scatterlist *dst = req->dst;
	u32 tmp[2];
	int err;

	cryptlen -= authsize;

	if (req->src != dst) {
		err = crypto_authenc_esn_copy(req, assoclen + cryptlen);
		if (err)
			return err;
	}

	scatterwalk_map_and_copy(ihash, req->src, assoclen + cryptlen,
				 authsize, 0);

	if (!authsize)
		goto tail;

	/* Move high-order bits of sequence number to the end. */
	scatterwalk_map_and_copy(tmp, dst, 0, 8, 0);
	scatterwalk_map_and_copy(tmp, dst, 4, 4, 1);
	scatterwalk_map_and_copy(tmp + 1, dst, assoclen + cryptlen, 4, 1);

	sg_init_table(areq_ctx->dst, 2);
	dst = scatterwalk_ffwd(areq_ctx->dst, dst, 4);

	ahash_request_set_tfm(ahreq, auth);
	ahash_request_set_crypt(ahreq, dst, ohash, assoclen + cryptlen);
	ahash_request_set_callback(ahreq, aead_request_flags(req),
				   authenc_esn_verify_ahash_done, req);

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

tail:
	return crypto_authenc_esn_decrypt_tail(req, aead_request_flags(req));
}

static int crypto_authenc_esn_init_tfm(struct crypto_aead *tfm)
{
	struct aead_instance *inst = aead_alg_instance(tfm);
	struct authenc_esn_instance_ctx *ictx = aead_instance_ctx(inst);
	struct crypto_authenc_esn_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;

	ctx->reqoff = ALIGN(2 * crypto_ahash_digestsize(auth),
			    crypto_ahash_alignmask(auth) + 1);

	crypto_aead_set_reqsize(
		tfm,
		sizeof(struct authenc_esn_request_ctx) +
		ctx->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_esn_exit_tfm(struct crypto_aead *tfm)
{
	struct crypto_authenc_esn_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_esn_free(struct aead_instance *inst)
{
	struct authenc_esn_instance_ctx *ctx = aead_instance_ctx(inst);

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

static int crypto_authenc_esn_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_esn_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);

	err = -ENAMETOOLONG;
	if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
		     "authencesn(%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,
		     "authencesn(%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_esn_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_esn_init_tfm;
	inst->alg.exit = crypto_authenc_esn_exit_tfm;

	inst->alg.setkey = crypto_authenc_esn_setkey;
	inst->alg.setauthsize = crypto_authenc_esn_setauthsize;
	inst->alg.encrypt = crypto_authenc_esn_encrypt;
	inst->alg.decrypt = crypto_authenc_esn_decrypt;

	inst->free = crypto_authenc_esn_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_esn_tmpl = {
	.name = "authencesn",
	.create = crypto_authenc_esn_create,
	.module = THIS_MODULE,
};

static int __init crypto_authenc_esn_module_init(void)
{
	return crypto_register_template(&crypto_authenc_esn_tmpl);
}

static void __exit crypto_authenc_esn_module_exit(void)
{
	crypto_unregister_template(&crypto_authenc_esn_tmpl);
}

module_init(crypto_authenc_esn_module_init);
module_exit(crypto_authenc_esn_module_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
MODULE_DESCRIPTION("AEAD wrapper for IPsec with extended sequence numbers");
MODULE_ALIAS_CRYPTO("authencesn");
Commit	Line	Data
a5079d08 SK	1	/*
	2	* authencesn.c - AEAD wrapper for IPsec with extended sequence numbers,
	3	* derived from authenc.c
	4	*
	5	* Copyright (C) 2010 secunet Security Networks AG
	6	* Copyright (C) 2010 Steffen Klassert <steffen.klassert@secunet.com>
104880a6	7	* Copyright (c) 2015 Herbert Xu <herbert@gondor.apana.org.au>
a5079d08 SK	8	*
	9	* This program is free software; you can redistribute it and/or modify it
	10	* under the terms of the GNU General Public License as published by the Free
	11	* Software Foundation; either version 2 of the License, or (at your option)
	12	* any later version.
	13	*
	14	*/
	15
7fb2a4bd	16	#include <crypto/internal/aead.h>
a5079d08 SK	17	#include <crypto/internal/hash.h>
	18	#include <crypto/internal/skcipher.h>
	19	#include <crypto/authenc.h>
104880a6	20	#include <crypto/null.h>
a5079d08 SK	21	#include <crypto/scatterwalk.h>
	22	#include <linux/err.h>
	23	#include <linux/init.h>
	24	#include <linux/kernel.h>
	25	#include <linux/module.h>
	26	#include <linux/rtnetlink.h>
	27	#include <linux/slab.h>
	28	#include <linux/spinlock.h>
	29
	30	struct authenc_esn_instance_ctx {
	31	struct crypto_ahash_spawn auth;
	32	struct crypto_skcipher_spawn enc;
	33	};
	34
	35	struct crypto_authenc_esn_ctx {
	36	unsigned int reqoff;
	37	struct crypto_ahash *auth;
e75445a8 HX	38	struct crypto_skcipher *enc;
e75445a8 HX	39	struct crypto_skcipher *null;
a5079d08 SK	40	};
	41
	42	struct authenc_esn_request_ctx {
104880a6 HX	43	struct scatterlist src[2];
104880a6 HX	44	struct scatterlist dst[2];
a5079d08 SK	45	char tail[];
	46	};
	47
	48	static void authenc_esn_request_complete(struct aead_request *req, int err)
	49	{
	50	if (err != -EINPROGRESS)
	51	aead_request_complete(req, err);
	52	}
	53
104880a6 HX	54	static int crypto_authenc_esn_setauthsize(struct crypto_aead *authenc_esn,
	55	unsigned int authsize)
	56	{
	57	if (authsize > 0 && authsize < 4)
	58	return -EINVAL;
	59
	60	return 0;
	61	}
	62
a5079d08 SK	63	static int crypto_authenc_esn_setkey(struct crypto_aead authenc_esn, const u8 key,
	64	unsigned int keylen)
	65	{
a5079d08 SK	66	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
a5079d08 SK	67	struct crypto_ahash *auth = ctx->auth;
e75445a8	68	struct crypto_skcipher *enc = ctx->enc;
fddc2c43	69	struct crypto_authenc_keys keys;
a5079d08 SK	70	int err = -EINVAL;
a5079d08 SK	71
fddc2c43	72	if (crypto_authenc_extractkeys(&keys, key, keylen) != 0)
a5079d08	73	goto badkey;
a5079d08 SK	74
	75	crypto_ahash_clear_flags(auth, CRYPTO_TFM_REQ_MASK);
	76	crypto_ahash_set_flags(auth, crypto_aead_get_flags(authenc_esn) &
	77	CRYPTO_TFM_REQ_MASK);
fddc2c43	78	err = crypto_ahash_setkey(auth, keys.authkey, keys.authkeylen);
a5079d08 SK	79	crypto_aead_set_flags(authenc_esn, crypto_ahash_get_flags(auth) &
	80	CRYPTO_TFM_RES_MASK);
	81
	82	if (err)
	83	goto out;
	84
e75445a8 HX	85	crypto_skcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK);
e75445a8 HX	86	crypto_skcipher_set_flags(enc, crypto_aead_get_flags(authenc_esn) &
a5079d08	87	CRYPTO_TFM_REQ_MASK);
e75445a8 HX	88	err = crypto_skcipher_setkey(enc, keys.enckey, keys.enckeylen);
e75445a8 HX	89	crypto_aead_set_flags(authenc_esn, crypto_skcipher_get_flags(enc) &
a5079d08 SK	90	CRYPTO_TFM_RES_MASK);
	91
	92	out:
	93	return err;
	94
	95	badkey:
	96	crypto_aead_set_flags(authenc_esn, CRYPTO_TFM_RES_BAD_KEY_LEN);
	97	goto out;
	98	}
	99
104880a6 HX	100	static int crypto_authenc_esn_genicv_tail(struct aead_request *req,
104880a6 HX	101	unsigned int flags)
a5079d08	102	{
a5079d08 SK	103	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
	104	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
	105	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
104880a6 HX	106	struct crypto_ahash *auth = ctx->auth;
	107	u8 hash = PTR_ALIGN((u8 )areq_ctx->tail,
	108	crypto_ahash_alignmask(auth) + 1);
	109	unsigned int authsize = crypto_aead_authsize(authenc_esn);
	110	unsigned int assoclen = req->assoclen;
	111	unsigned int cryptlen = req->cryptlen;
	112	struct scatterlist *dst = req->dst;
	113	u32 tmp[2];
a5079d08	114
104880a6 HX	115	/* Move high-order bits of sequence number back. */
	116	scatterwalk_map_and_copy(tmp, dst, 4, 4, 0);
	117	scatterwalk_map_and_copy(tmp + 1, dst, assoclen + cryptlen, 4, 0);
	118	scatterwalk_map_and_copy(tmp, dst, 0, 8, 1);
a5079d08	119
104880a6 HX	120	scatterwalk_map_and_copy(hash, dst, assoclen + cryptlen, authsize, 1);
104880a6 HX	121	return 0;
a5079d08 SK	122	}
a5079d08 SK	123
a5079d08 SK	124	static void authenc_esn_geniv_ahash_done(struct crypto_async_request *areq,
	125	int err)
	126	{
	127	struct aead_request *req = areq->data;
a5079d08	128
104880a6	129	err = err ?: crypto_authenc_esn_genicv_tail(req, 0);
a5079d08 SK	130	aead_request_complete(req, err);
	131	}
	132
104880a6 HX	133	static int crypto_authenc_esn_genicv(struct aead_request *req,
104880a6 HX	134	unsigned int flags)
a5079d08	135	{
a5079d08	136	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
a5079d08	137	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
a5079d08	138	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
104880a6 HX	139	struct crypto_ahash *auth = ctx->auth;
	140	u8 hash = PTR_ALIGN((u8 )areq_ctx->tail,
	141	crypto_ahash_alignmask(auth) + 1);
a5079d08	142	struct ahash_request ahreq = (void )(areq_ctx->tail + ctx->reqoff);
104880a6 HX	143	unsigned int authsize = crypto_aead_authsize(authenc_esn);
104880a6 HX	144	unsigned int assoclen = req->assoclen;
a5079d08	145	unsigned int cryptlen = req->cryptlen;
104880a6 HX	146	struct scatterlist *dst = req->dst;
104880a6 HX	147	u32 tmp[2];
a5079d08	148
104880a6 HX	149	if (!authsize)
104880a6 HX	150	return 0;
a5079d08	151
104880a6 HX	152	/* Move high-order bits of sequence number to the end. */
	153	scatterwalk_map_and_copy(tmp, dst, 0, 8, 0);
	154	scatterwalk_map_and_copy(tmp, dst, 4, 4, 1);
	155	scatterwalk_map_and_copy(tmp + 1, dst, assoclen + cryptlen, 4, 1);
a5079d08	156
104880a6 HX	157	sg_init_table(areq_ctx->dst, 2);
104880a6 HX	158	dst = scatterwalk_ffwd(areq_ctx->dst, dst, 4);
a5079d08	159
104880a6 HX	160	ahash_request_set_tfm(ahreq, auth);
	161	ahash_request_set_crypt(ahreq, dst, hash, assoclen + cryptlen);
	162	ahash_request_set_callback(ahreq, flags,
	163	authenc_esn_geniv_ahash_done, req);
a5079d08	164
104880a6 HX	165	return crypto_ahash_digest(ahreq) ?:
104880a6 HX	166	crypto_authenc_esn_genicv_tail(req, aead_request_flags(req));
a5079d08 SK	167	}
	168
	169
104880a6 HX	170	static void crypto_authenc_esn_encrypt_done(struct crypto_async_request *req,
104880a6 HX	171	int err)
a5079d08	172	{
104880a6	173	struct aead_request *areq = req->data;
a5079d08	174
104880a6 HX	175	if (!err)
104880a6 HX	176	err = crypto_authenc_esn_genicv(areq, 0);
a5079d08	177
104880a6	178	authenc_esn_request_complete(areq, err);
a5079d08 SK	179	}
a5079d08 SK	180
104880a6	181	static int crypto_authenc_esn_copy(struct aead_request *req, unsigned int len)
a5079d08 SK	182	{
	183	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
	184	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
e75445a8	185	SKCIPHER_REQUEST_ON_STACK(skreq, ctx->null);
a5079d08	186
e75445a8 HX	187	skcipher_request_set_tfm(skreq, ctx->null);
	188	skcipher_request_set_callback(skreq, aead_request_flags(req),
	189	NULL, NULL);
	190	skcipher_request_set_crypt(skreq, req->src, req->dst, len, NULL);
	191
	192	return crypto_skcipher_encrypt(skreq);
a5079d08 SK	193	}
a5079d08 SK	194
104880a6	195	static int crypto_authenc_esn_encrypt(struct aead_request *req)
a5079d08 SK	196	{
	197	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
	198	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
104880a6	199	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
e75445a8 HX	200	struct skcipher_request skreq = (void )(areq_ctx->tail +
	201	ctx->reqoff);
	202	struct crypto_skcipher *enc = ctx->enc;
104880a6	203	unsigned int assoclen = req->assoclen;
a5079d08	204	unsigned int cryptlen = req->cryptlen;
104880a6 HX	205	struct scatterlist src, dst;
104880a6 HX	206	int err;
a5079d08	207
104880a6 HX	208	sg_init_table(areq_ctx->src, 2);
	209	src = scatterwalk_ffwd(areq_ctx->src, req->src, assoclen);
	210	dst = src;
a5079d08	211
104880a6 HX	212	if (req->src != req->dst) {
	213	err = crypto_authenc_esn_copy(req, assoclen);
	214	if (err)
	215	return err;
a5079d08	216
104880a6 HX	217	sg_init_table(areq_ctx->dst, 2);
104880a6 HX	218	dst = scatterwalk_ffwd(areq_ctx->dst, req->dst, assoclen);
a5079d08 SK	219	}
a5079d08 SK	220
e75445a8 HX	221	skcipher_request_set_tfm(skreq, enc);
	222	skcipher_request_set_callback(skreq, aead_request_flags(req),
	223	crypto_authenc_esn_encrypt_done, req);
	224	skcipher_request_set_crypt(skreq, src, dst, cryptlen, req->iv);
a5079d08	225
e75445a8	226	err = crypto_skcipher_encrypt(skreq);
a5079d08 SK	227	if (err)
	228	return err;
	229
104880a6	230	return crypto_authenc_esn_genicv(req, aead_request_flags(req));
a5079d08 SK	231	}
a5079d08 SK	232
104880a6 HX	233	static int crypto_authenc_esn_decrypt_tail(struct aead_request *req,
104880a6 HX	234	unsigned int flags)
a5079d08	235	{
104880a6 HX	236	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
	237	unsigned int authsize = crypto_aead_authsize(authenc_esn);
	238	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
	239	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
e75445a8 HX	240	struct skcipher_request skreq = (void )(areq_ctx->tail +
e75445a8 HX	241	ctx->reqoff);
104880a6 HX	242	struct crypto_ahash *auth = ctx->auth;
	243	u8 ohash = PTR_ALIGN((u8 )areq_ctx->tail,
	244	crypto_ahash_alignmask(auth) + 1);
	245	unsigned int cryptlen = req->cryptlen - authsize;
	246	unsigned int assoclen = req->assoclen;
	247	struct scatterlist *dst = req->dst;
	248	u8 *ihash = ohash + crypto_ahash_digestsize(auth);
	249	u32 tmp[2];
a5079d08	250
104880a6 HX	251	/* Move high-order bits of sequence number back. */
	252	scatterwalk_map_and_copy(tmp, dst, 4, 4, 0);
	253	scatterwalk_map_and_copy(tmp + 1, dst, assoclen + cryptlen, 4, 0);
	254	scatterwalk_map_and_copy(tmp, dst, 0, 8, 1);
a5079d08	255
104880a6 HX	256	if (crypto_memneq(ihash, ohash, authsize))
104880a6 HX	257	return -EBADMSG;
a5079d08	258
104880a6 HX	259	sg_init_table(areq_ctx->dst, 2);
104880a6 HX	260	dst = scatterwalk_ffwd(areq_ctx->dst, dst, assoclen);
a5079d08	261
e75445a8 HX	262	skcipher_request_set_tfm(skreq, ctx->enc);
	263	skcipher_request_set_callback(skreq, flags,
	264	req->base.complete, req->base.data);
	265	skcipher_request_set_crypt(skreq, dst, dst, cryptlen, req->iv);
a5079d08	266
e75445a8	267	return crypto_skcipher_decrypt(skreq);
a5079d08 SK	268	}
a5079d08 SK	269
104880a6 HX	270	static void authenc_esn_verify_ahash_done(struct crypto_async_request *areq,
104880a6 HX	271	int err)
a5079d08	272	{
104880a6	273	struct aead_request *req = areq->data;
a5079d08	274
104880a6 HX	275	err = err ?: crypto_authenc_esn_decrypt_tail(req, 0);
104880a6 HX	276	aead_request_complete(req, err);
a5079d08 SK	277	}
a5079d08 SK	278
104880a6	279	static int crypto_authenc_esn_decrypt(struct aead_request *req)
a5079d08 SK	280	{
	281	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
	282	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
104880a6 HX	283	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
	284	struct ahash_request ahreq = (void )(areq_ctx->tail + ctx->reqoff);
	285	unsigned int authsize = crypto_aead_authsize(authenc_esn);
	286	struct crypto_ahash *auth = ctx->auth;
	287	u8 ohash = PTR_ALIGN((u8 )areq_ctx->tail,
	288	crypto_ahash_alignmask(auth) + 1);
	289	unsigned int assoclen = req->assoclen;
	290	unsigned int cryptlen = req->cryptlen;
	291	u8 *ihash = ohash + crypto_ahash_digestsize(auth);
	292	struct scatterlist *dst = req->dst;
	293	u32 tmp[2];
	294	int err;
a5079d08	295
104880a6	296	cryptlen -= authsize;
a5079d08	297
104880a6 HX	298	if (req->src != dst) {
	299	err = crypto_authenc_esn_copy(req, assoclen + cryptlen);
	300	if (err)
	301	return err;
	302	}
a5079d08	303
104880a6 HX	304	scatterwalk_map_and_copy(ihash, req->src, assoclen + cryptlen,
104880a6 HX	305	authsize, 0);
a5079d08	306
104880a6 HX	307	if (!authsize)
104880a6 HX	308	goto tail;
a5079d08	309
104880a6 HX	310	/* Move high-order bits of sequence number to the end. */
	311	scatterwalk_map_and_copy(tmp, dst, 0, 8, 0);
	312	scatterwalk_map_and_copy(tmp, dst, 4, 4, 1);
	313	scatterwalk_map_and_copy(tmp + 1, dst, assoclen + cryptlen, 4, 1);
a5079d08	314
104880a6 HX	315	sg_init_table(areq_ctx->dst, 2);
104880a6 HX	316	dst = scatterwalk_ffwd(areq_ctx->dst, dst, 4);
a5079d08	317
104880a6 HX	318	ahash_request_set_tfm(ahreq, auth);
	319	ahash_request_set_crypt(ahreq, dst, ohash, assoclen + cryptlen);
	320	ahash_request_set_callback(ahreq, aead_request_flags(req),
	321	authenc_esn_verify_ahash_done, req);
a5079d08	322
104880a6	323	err = crypto_ahash_digest(ahreq);
a5079d08 SK	324	if (err)
	325	return err;
	326
104880a6 HX	327	tail:
104880a6 HX	328	return crypto_authenc_esn_decrypt_tail(req, aead_request_flags(req));
a5079d08 SK	329	}
a5079d08 SK	330
104880a6	331	static int crypto_authenc_esn_init_tfm(struct crypto_aead *tfm)
a5079d08	332	{
104880a6 HX	333	struct aead_instance *inst = aead_alg_instance(tfm);
	334	struct authenc_esn_instance_ctx *ictx = aead_instance_ctx(inst);
	335	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(tfm);
a5079d08	336	struct crypto_ahash *auth;
e75445a8 HX	337	struct crypto_skcipher *enc;
e75445a8 HX	338	struct crypto_skcipher *null;
a5079d08 SK	339	int err;
	340
	341	auth = crypto_spawn_ahash(&ictx->auth);
	342	if (IS_ERR(auth))
	343	return PTR_ERR(auth);
	344
60425a8b	345	enc = crypto_spawn_skcipher(&ictx->enc);
a5079d08 SK	346	err = PTR_ERR(enc);
	347	if (IS_ERR(enc))
	348	goto err_free_ahash;
	349
e75445a8	350	null = crypto_get_default_null_skcipher2();
104880a6 HX	351	err = PTR_ERR(null);
	352	if (IS_ERR(null))
	353	goto err_free_skcipher;
	354
a5079d08 SK	355	ctx->auth = auth;
a5079d08 SK	356	ctx->enc = enc;
104880a6	357	ctx->null = null;
a5079d08	358
104880a6 HX	359	ctx->reqoff = ALIGN(2 * crypto_ahash_digestsize(auth),
104880a6 HX	360	crypto_ahash_alignmask(auth) + 1);
a5079d08	361
104880a6 HX	362	crypto_aead_set_reqsize(
104880a6 HX	363	tfm,
6650d09b HX	364	sizeof(struct authenc_esn_request_ctx) +
	365	ctx->reqoff +
	366	max_t(unsigned int,
e75445a8 HX	367	crypto_ahash_reqsize(auth) +
	368	sizeof(struct ahash_request),
	369	sizeof(struct skcipher_request) +
	370	crypto_skcipher_reqsize(enc)));
a5079d08 SK	371
	372	return 0;
	373
104880a6	374	err_free_skcipher:
e75445a8	375	crypto_free_skcipher(enc);
a5079d08 SK	376	err_free_ahash:
	377	crypto_free_ahash(auth);
	378	return err;
	379	}
	380
104880a6	381	static void crypto_authenc_esn_exit_tfm(struct crypto_aead *tfm)
a5079d08	382	{
104880a6	383	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(tfm);
a5079d08 SK	384
a5079d08 SK	385	crypto_free_ahash(ctx->auth);
e75445a8 HX	386	crypto_free_skcipher(ctx->enc);
e75445a8 HX	387	crypto_put_default_null_skcipher2();
104880a6 HX	388	}
	389
	390	static void crypto_authenc_esn_free(struct aead_instance *inst)
	391	{
	392	struct authenc_esn_instance_ctx *ctx = aead_instance_ctx(inst);
	393
	394	crypto_drop_skcipher(&ctx->enc);
	395	crypto_drop_ahash(&ctx->auth);
	396	kfree(inst);
a5079d08 SK	397	}
a5079d08 SK	398
104880a6 HX	399	static int crypto_authenc_esn_create(struct crypto_template *tmpl,
104880a6 HX	400	struct rtattr **tb)
a5079d08 SK	401	{
a5079d08 SK	402	struct crypto_attr_type *algt;
104880a6	403	struct aead_instance *inst;
a5079d08 SK	404	struct hash_alg_common *auth;
a5079d08 SK	405	struct crypto_alg *auth_base;
e75445a8	406	struct skcipher_alg *enc;
a5079d08 SK	407	struct authenc_esn_instance_ctx *ctx;
	408	const char *enc_name;
	409	int err;
	410
	411	algt = crypto_get_attr_type(tb);
a5079d08	412	if (IS_ERR(algt))
104880a6	413	return PTR_ERR(algt);
a5079d08	414
5e4b8c1f	415	if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
104880a6	416	return -EINVAL;
a5079d08 SK	417
a5079d08 SK	418	auth = ahash_attr_alg(tb[1], CRYPTO_ALG_TYPE_HASH,
927ef32d HX	419	CRYPTO_ALG_TYPE_AHASH_MASK \|
927ef32d HX	420	crypto_requires_sync(algt->type, algt->mask));
a5079d08	421	if (IS_ERR(auth))
104880a6	422	return PTR_ERR(auth);
a5079d08 SK	423
	424	auth_base = &auth->base;
	425
	426	enc_name = crypto_attr_alg_name(tb[2]);
	427	err = PTR_ERR(enc_name);
	428	if (IS_ERR(enc_name))
	429	goto out_put_auth;
	430
	431	inst = kzalloc(sizeof(inst) + sizeof(ctx), GFP_KERNEL);
	432	err = -ENOMEM;
	433	if (!inst)
	434	goto out_put_auth;
	435
104880a6	436	ctx = aead_instance_ctx(inst);
a5079d08	437
104880a6 HX	438	err = crypto_init_ahash_spawn(&ctx->auth, auth,
104880a6 HX	439	aead_crypto_instance(inst));
a5079d08 SK	440	if (err)
	441	goto err_free_inst;
	442
104880a6	443	crypto_set_skcipher_spawn(&ctx->enc, aead_crypto_instance(inst));
a35528ec EB	444	err = crypto_grab_skcipher(&ctx->enc, enc_name, 0,
	445	crypto_requires_sync(algt->type,
	446	algt->mask));
a5079d08 SK	447	if (err)
	448	goto err_drop_auth;
	449
e75445a8	450	enc = crypto_spawn_skcipher_alg(&ctx->enc);
a5079d08 SK	451
a5079d08 SK	452	err = -ENAMETOOLONG;
104880a6 HX	453	if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
104880a6 HX	454	"authencesn(%s,%s)", auth_base->cra_name,
e75445a8	455	enc->base.cra_name) >= CRYPTO_MAX_ALG_NAME)
a5079d08 SK	456	goto err_drop_enc;
a5079d08 SK	457
104880a6	458	if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
a5079d08	459	"authencesn(%s,%s)", auth_base->cra_driver_name,
e75445a8	460	enc->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
a5079d08 SK	461	goto err_drop_enc;
a5079d08 SK	462
e75445a8 HX	463	inst->alg.base.cra_flags = (auth_base->cra_flags \|
	464	enc->base.cra_flags) & CRYPTO_ALG_ASYNC;
	465	inst->alg.base.cra_priority = enc->base.cra_priority * 10 +
104880a6	466	auth_base->cra_priority;
e75445a8	467	inst->alg.base.cra_blocksize = enc->base.cra_blocksize;
104880a6	468	inst->alg.base.cra_alignmask = auth_base->cra_alignmask \|
e75445a8	469	enc->base.cra_alignmask;
104880a6 HX	470	inst->alg.base.cra_ctxsize = sizeof(struct crypto_authenc_esn_ctx);
104880a6 HX	471
e75445a8 HX	472	inst->alg.ivsize = crypto_skcipher_alg_ivsize(enc);
e75445a8 HX	473	inst->alg.chunksize = crypto_skcipher_alg_chunksize(enc);
104880a6	474	inst->alg.maxauthsize = auth->digestsize;
a5079d08	475
104880a6 HX	476	inst->alg.init = crypto_authenc_esn_init_tfm;
104880a6 HX	477	inst->alg.exit = crypto_authenc_esn_exit_tfm;
a5079d08	478
104880a6 HX	479	inst->alg.setkey = crypto_authenc_esn_setkey;
	480	inst->alg.setauthsize = crypto_authenc_esn_setauthsize;
	481	inst->alg.encrypt = crypto_authenc_esn_encrypt;
	482	inst->alg.decrypt = crypto_authenc_esn_decrypt;
a5079d08	483
104880a6	484	inst->free = crypto_authenc_esn_free,
a5079d08	485
104880a6 HX	486	err = aead_register_instance(tmpl, inst);
	487	if (err)
	488	goto err_drop_enc;
a5079d08 SK	489
	490	out:
	491	crypto_mod_put(auth_base);
104880a6	492	return err;
a5079d08 SK	493
	494	err_drop_enc:
	495	crypto_drop_skcipher(&ctx->enc);
	496	err_drop_auth:
	497	crypto_drop_ahash(&ctx->auth);
	498	err_free_inst:
	499	kfree(inst);
	500	out_put_auth:
a5079d08 SK	501	goto out;
	502	}
	503
a5079d08 SK	504	static struct crypto_template crypto_authenc_esn_tmpl = {
a5079d08 SK	505	.name = "authencesn",
104880a6	506	.create = crypto_authenc_esn_create,
a5079d08 SK	507	.module = THIS_MODULE,
	508	};
	509
	510	static int __init crypto_authenc_esn_module_init(void)
	511	{
	512	return crypto_register_template(&crypto_authenc_esn_tmpl);
	513	}
	514
	515	static void __exit crypto_authenc_esn_module_exit(void)
	516	{
	517	crypto_unregister_template(&crypto_authenc_esn_tmpl);
	518	}
	519
	520	module_init(crypto_authenc_esn_module_init);
	521	module_exit(crypto_authenc_esn_module_exit);
	522
	523	MODULE_LICENSE("GPL");
	524	MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
	525	MODULE_DESCRIPTION("AEAD wrapper for IPsec with extended sequence numbers");
4943ba16	526	MODULE_ALIAS_CRYPTO("authencesn");