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

/*
 * algif_hash: User-space interface for hash algorithms
 *
 * This file provides the user-space API for hash algorithms.
 *
 * Copyright (c) 2010 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/hash.h>
#include <crypto/if_alg.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/net.h>
#include <net/sock.h>

struct hash_ctx {
	struct af_alg_sgl sgl;

	u8 *result;

	struct af_alg_completion completion;

	unsigned int len;
	bool more;

	struct ahash_request req;
};

struct algif_hash_tfm {
	struct crypto_ahash *hash;
	bool has_key;
};

static int hash_alloc_result(struct sock *sk, struct hash_ctx *ctx)
{
	unsigned ds;

	if (ctx->result)
		return 0;

	ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));

	ctx->result = sock_kmalloc(sk, ds, GFP_KERNEL);
	if (!ctx->result)
		return -ENOMEM;

	memset(ctx->result, 0, ds);

	return 0;
}

static void hash_free_result(struct sock *sk, struct hash_ctx *ctx)
{
	unsigned ds;

	if (!ctx->result)
		return;

	ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));

	sock_kzfree_s(sk, ctx->result, ds);
	ctx->result = NULL;
}

static int hash_sendmsg(struct socket *sock, struct msghdr *msg,
			size_t ignored)
{
	int limit = ALG_MAX_PAGES * PAGE_SIZE;
	struct sock *sk = sock->sk;
	struct alg_sock *ask = alg_sk(sk);
	struct hash_ctx *ctx = ask->private;
	long copied = 0;
	int err;

	if (limit > sk->sk_sndbuf)
		limit = sk->sk_sndbuf;

	lock_sock(sk);
	if (!ctx->more) {
		if ((msg->msg_flags & MSG_MORE))
			hash_free_result(sk, ctx);

		err = af_alg_wait_for_completion(crypto_ahash_init(&ctx->req),
						&ctx->completion);
		if (err)
			goto unlock;
	}

	ctx->more = 0;

	while (msg_data_left(msg)) {
		int len = msg_data_left(msg);

		if (len > limit)
			len = limit;

		len = af_alg_make_sg(&ctx->sgl, &msg->msg_iter, len);
		if (len < 0) {
			err = copied ? 0 : len;
			goto unlock;
		}

		ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, NULL, len);

		err = af_alg_wait_for_completion(crypto_ahash_update(&ctx->req),
						 &ctx->completion);
		af_alg_free_sg(&ctx->sgl);
		if (err)
			goto unlock;

		copied += len;
		iov_iter_advance(&msg->msg_iter, len);
	}

	err = 0;

	ctx->more = msg->msg_flags & MSG_MORE;
	if (!ctx->more) {
		err = hash_alloc_result(sk, ctx);
		if (err)
			goto unlock;

		ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
		err = af_alg_wait_for_completion(crypto_ahash_final(&ctx->req),
						 &ctx->completion);
	}

unlock:
	release_sock(sk);

	return err ?: copied;
}

static ssize_t hash_sendpage(struct socket *sock, struct page *page,
			     int offset, size_t size, int flags)
{
	struct sock *sk = sock->sk;
	struct alg_sock *ask = alg_sk(sk);
	struct hash_ctx *ctx = ask->private;
	int err;

	if (flags & MSG_SENDPAGE_NOTLAST)
		flags |= MSG_MORE;

	lock_sock(sk);
	sg_init_table(ctx->sgl.sg, 1);
	sg_set_page(ctx->sgl.sg, page, size, offset);

	if (!(flags & MSG_MORE)) {
		err = hash_alloc_result(sk, ctx);
		if (err)
			goto unlock;
	} else if (!ctx->more)
		hash_free_result(sk, ctx);

	ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, ctx->result, size);

	if (!(flags & MSG_MORE)) {
		if (ctx->more)
			err = crypto_ahash_finup(&ctx->req);
		else
			err = crypto_ahash_digest(&ctx->req);
	} else {
		if (!ctx->more) {
			err = crypto_ahash_init(&ctx->req);
			err = af_alg_wait_for_completion(err, &ctx->completion);
			if (err)
				goto unlock;
		}

		err = crypto_ahash_update(&ctx->req);
	}

	err = af_alg_wait_for_completion(err, &ctx->completion);
	if (err)
		goto unlock;

	ctx->more = flags & MSG_MORE;

unlock:
	release_sock(sk);

	return err ?: size;
}

static int hash_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
			int flags)
{
	struct sock *sk = sock->sk;
	struct alg_sock *ask = alg_sk(sk);
	struct hash_ctx *ctx = ask->private;
	unsigned ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
	bool result;
	int err;

	if (len > ds)
		len = ds;
	else if (len < ds)
		msg->msg_flags |= MSG_TRUNC;

	lock_sock(sk);
	result = ctx->result;
	err = hash_alloc_result(sk, ctx);
	if (err)
		goto unlock;

	ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);

	if (!result && !ctx->more) {
		err = af_alg_wait_for_completion(
				crypto_ahash_init(&ctx->req),
				&ctx->completion);
		if (err)
			goto unlock;
	}

	if (!result || ctx->more) {
		ctx->more = 0;
		err = af_alg_wait_for_completion(crypto_ahash_final(&ctx->req),
						 &ctx->completion);
		if (err)
			goto unlock;
	}

	err = memcpy_to_msg(msg, ctx->result, len);

unlock:
	hash_free_result(sk, ctx);
	release_sock(sk);

	return err ?: len;
}

static int hash_accept(struct socket *sock, struct socket *newsock, int flags)
{
	struct sock *sk = sock->sk;
	struct alg_sock *ask = alg_sk(sk);
	struct hash_ctx *ctx = ask->private;
	struct ahash_request *req = &ctx->req;
	char state[crypto_ahash_statesize(crypto_ahash_reqtfm(req)) ? : 1];
	struct sock *sk2;
	struct alg_sock *ask2;
	struct hash_ctx *ctx2;
	bool more;
	int err;

	lock_sock(sk);
	more = ctx->more;
	err = more ? crypto_ahash_export(req, state) : 0;
	release_sock(sk);

	if (err)
		return err;

	err = af_alg_accept(ask->parent, newsock);
	if (err)
		return err;

	sk2 = newsock->sk;
	ask2 = alg_sk(sk2);
	ctx2 = ask2->private;
	ctx2->more = more;

	if (!more)
		return err;

	err = crypto_ahash_import(&ctx2->req, state);
	if (err) {
		sock_orphan(sk2);
		sock_put(sk2);
	}

	return err;
}

static struct proto_ops algif_hash_ops = {
	.family		=	PF_ALG,

	.connect	=	sock_no_connect,
	.socketpair	=	sock_no_socketpair,
	.getname	=	sock_no_getname,
	.ioctl		=	sock_no_ioctl,
	.listen		=	sock_no_listen,
	.shutdown	=	sock_no_shutdown,
	.getsockopt	=	sock_no_getsockopt,
	.mmap		=	sock_no_mmap,
	.bind		=	sock_no_bind,
	.setsockopt	=	sock_no_setsockopt,
	.poll		=	sock_no_poll,

	.release	=	af_alg_release,
	.sendmsg	=	hash_sendmsg,
	.sendpage	=	hash_sendpage,
	.recvmsg	=	hash_recvmsg,
	.accept		=	hash_accept,
};

static int hash_check_key(struct socket *sock)
{
	int err = 0;
	struct sock *psk;
	struct alg_sock *pask;
	struct algif_hash_tfm *tfm;
	struct sock *sk = sock->sk;
	struct alg_sock *ask = alg_sk(sk);

	lock_sock(sk);
	if (ask->refcnt)
		goto unlock_child;

	psk = ask->parent;
	pask = alg_sk(ask->parent);
	tfm = pask->private;

	err = -ENOKEY;
	lock_sock_nested(psk, SINGLE_DEPTH_NESTING);
	if (!tfm->has_key)
		goto unlock;

	if (!pask->refcnt++)
		sock_hold(psk);

	ask->refcnt = 1;
	sock_put(psk);

	err = 0;

unlock:
	release_sock(psk);
unlock_child:
	release_sock(sk);

	return err;
}

static int hash_sendmsg_nokey(struct socket *sock, struct msghdr *msg,
			      size_t size)
{
	int err;

	err = hash_check_key(sock);
	if (err)
		return err;

	return hash_sendmsg(sock, msg, size);
}

static ssize_t hash_sendpage_nokey(struct socket *sock, struct page *page,
				   int offset, size_t size, int flags)
{
	int err;

	err = hash_check_key(sock);
	if (err)
		return err;

	return hash_sendpage(sock, page, offset, size, flags);
}

static int hash_recvmsg_nokey(struct socket *sock, struct msghdr *msg,
			      size_t ignored, int flags)
{
	int err;

	err = hash_check_key(sock);
	if (err)
		return err;

	return hash_recvmsg(sock, msg, ignored, flags);
}

static int hash_accept_nokey(struct socket *sock, struct socket *newsock,
			     int flags)
{
	int err;

	err = hash_check_key(sock);
	if (err)
		return err;

	return hash_accept(sock, newsock, flags);
}

static struct proto_ops algif_hash_ops_nokey = {
	.family		=	PF_ALG,

	.connect	=	sock_no_connect,
	.socketpair	=	sock_no_socketpair,
	.getname	=	sock_no_getname,
	.ioctl		=	sock_no_ioctl,
	.listen		=	sock_no_listen,
	.shutdown	=	sock_no_shutdown,
	.getsockopt	=	sock_no_getsockopt,
	.mmap		=	sock_no_mmap,
	.bind		=	sock_no_bind,
	.setsockopt	=	sock_no_setsockopt,
	.poll		=	sock_no_poll,

	.release	=	af_alg_release,
	.sendmsg	=	hash_sendmsg_nokey,
	.sendpage	=	hash_sendpage_nokey,
	.recvmsg	=	hash_recvmsg_nokey,
	.accept		=	hash_accept_nokey,
};

static void *hash_bind(const char *name, u32 type, u32 mask)
{
	struct algif_hash_tfm *tfm;
	struct crypto_ahash *hash;

	tfm = kzalloc(sizeof(*tfm), GFP_KERNEL);
	if (!tfm)
		return ERR_PTR(-ENOMEM);

	hash = crypto_alloc_ahash(name, type, mask);
	if (IS_ERR(hash)) {
		kfree(tfm);
		return ERR_CAST(hash);
	}

	tfm->hash = hash;

	return tfm;
}

static void hash_release(void *private)
{
	struct algif_hash_tfm *tfm = private;

	crypto_free_ahash(tfm->hash);
	kfree(tfm);
}

static int hash_setkey(void *private, const u8 *key, unsigned int keylen)
{
	struct algif_hash_tfm *tfm = private;
	int err;

	err = crypto_ahash_setkey(tfm->hash, key, keylen);
	tfm->has_key = !err;

	return err;
}

static void hash_sock_destruct(struct sock *sk)
{
	struct alg_sock *ask = alg_sk(sk);
	struct hash_ctx *ctx = ask->private;

	hash_free_result(sk, ctx);
	sock_kfree_s(sk, ctx, ctx->len);
	af_alg_release_parent(sk);
}

static int hash_accept_parent_nokey(void *private, struct sock *sk)
{
	struct hash_ctx *ctx;
	struct alg_sock *ask = alg_sk(sk);
	struct algif_hash_tfm *tfm = private;
	struct crypto_ahash *hash = tfm->hash;
	unsigned len = sizeof(*ctx) + crypto_ahash_reqsize(hash);

	ctx = sock_kmalloc(sk, len, GFP_KERNEL);
	if (!ctx)
		return -ENOMEM;

	ctx->result = NULL;
	ctx->len = len;
	ctx->more = 0;
	af_alg_init_completion(&ctx->completion);

	ask->private = ctx;

	ahash_request_set_tfm(&ctx->req, hash);
	ahash_request_set_callback(&ctx->req, CRYPTO_TFM_REQ_MAY_BACKLOG,
				   af_alg_complete, &ctx->completion);

	sk->sk_destruct = hash_sock_destruct;

	return 0;
}

static int hash_accept_parent(void *private, struct sock *sk)
{
	struct algif_hash_tfm *tfm = private;

	if (!tfm->has_key && crypto_ahash_has_setkey(tfm->hash))
		return -ENOKEY;

	return hash_accept_parent_nokey(private, sk);
}

static const struct af_alg_type algif_type_hash = {
	.bind		=	hash_bind,
	.release	=	hash_release,
	.setkey		=	hash_setkey,
	.accept		=	hash_accept_parent,
	.accept_nokey	=	hash_accept_parent_nokey,
	.ops		=	&algif_hash_ops,
	.ops_nokey	=	&algif_hash_ops_nokey,
	.name		=	"hash",
	.owner		=	THIS_MODULE
};

static int __init algif_hash_init(void)
{
	return af_alg_register_type(&algif_type_hash);
}

static void __exit algif_hash_exit(void)
{
	int err = af_alg_unregister_type(&algif_type_hash);
	BUG_ON(err);
}

module_init(algif_hash_init);
module_exit(algif_hash_exit);
MODULE_LICENSE("GPL");
Commit	Line	Data
fe869cdb HX	1	/*
	2	* algif_hash: User-space interface for hash algorithms
	3	*
	4	* This file provides the user-space API for hash algorithms.
	5	*
	6	* Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
	7	*
	8	* This program is free software; you can redistribute it and/or modify it
	9	* under the terms of the GNU General Public License as published by the Free
	10	* Software Foundation; either version 2 of the License, or (at your option)
	11	* any later version.
	12	*
	13	*/
	14
	15	#include <crypto/hash.h>
	16	#include <crypto/if_alg.h>
	17	#include <linux/init.h>
	18	#include <linux/kernel.h>
	19	#include <linux/mm.h>
	20	#include <linux/module.h>
	21	#include <linux/net.h>
	22	#include <net/sock.h>
	23
	24	struct hash_ctx {
	25	struct af_alg_sgl sgl;
	26
	27	u8 *result;
	28
	29	struct af_alg_completion completion;
	30
	31	unsigned int len;
	32	bool more;
	33
	34	struct ahash_request req;
	35	};
	36
6de62f15 HX	37	struct algif_hash_tfm {
	38	struct crypto_ahash *hash;
	39	bool has_key;
	40	};
	41
493b2ed3 HX	42	static int hash_alloc_result(struct sock sk, struct hash_ctx ctx)
	43	{
	44	unsigned ds;
	45
	46	if (ctx->result)
	47	return 0;
	48
	49	ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
	50
	51	ctx->result = sock_kmalloc(sk, ds, GFP_KERNEL);
	52	if (!ctx->result)
	53	return -ENOMEM;
	54
	55	memset(ctx->result, 0, ds);
	56
	57	return 0;
	58	}
	59
	60	static void hash_free_result(struct sock sk, struct hash_ctx ctx)
	61	{
	62	unsigned ds;
	63
	64	if (!ctx->result)
	65	return;
	66
	67	ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
	68
	69	sock_kzfree_s(sk, ctx->result, ds);
	70	ctx->result = NULL;
	71	}
	72
1b784140 YX	73	static int hash_sendmsg(struct socket sock, struct msghdr msg,
1b784140 YX	74	size_t ignored)
fe869cdb HX	75	{
	76	int limit = ALG_MAX_PAGES * PAGE_SIZE;
	77	struct sock *sk = sock->sk;
	78	struct alg_sock *ask = alg_sk(sk);
	79	struct hash_ctx *ctx = ask->private;
fe869cdb HX	80	long copied = 0;
	81	int err;
	82
	83	if (limit > sk->sk_sndbuf)
	84	limit = sk->sk_sndbuf;
	85
	86	lock_sock(sk);
	87	if (!ctx->more) {
493b2ed3 HX	88	if ((msg->msg_flags & MSG_MORE))
	89	hash_free_result(sk, ctx);
	90
fe097861 WR	91	err = af_alg_wait_for_completion(crypto_ahash_init(&ctx->req),
fe097861 WR	92	&ctx->completion);
fe869cdb HX	93	if (err)
	94	goto unlock;
	95	}
	96
	97	ctx->more = 0;
	98
01e97e65 AV	99	while (msg_data_left(msg)) {
01e97e65 AV	100	int len = msg_data_left(msg);
fe869cdb	101
1d10eb2f AV	102	if (len > limit)
1d10eb2f AV	103	len = limit;
fe869cdb	104
1d10eb2f AV	105	len = af_alg_make_sg(&ctx->sgl, &msg->msg_iter, len);
	106	if (len < 0) {
	107	err = copied ? 0 : len;
	108	goto unlock;
	109	}
fe869cdb	110
1d10eb2f	111	ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, NULL, len);
fe869cdb	112
1d10eb2f AV	113	err = af_alg_wait_for_completion(crypto_ahash_update(&ctx->req),
	114	&ctx->completion);
	115	af_alg_free_sg(&ctx->sgl);
	116	if (err)
	117	goto unlock;
fe869cdb	118
1d10eb2f AV	119	copied += len;
1d10eb2f AV	120	iov_iter_advance(&msg->msg_iter, len);
fe869cdb HX	121	}
	122
	123	err = 0;
	124
	125	ctx->more = msg->msg_flags & MSG_MORE;
	126	if (!ctx->more) {
493b2ed3 HX	127	err = hash_alloc_result(sk, ctx);
	128	if (err)
	129	goto unlock;
	130
fe869cdb HX	131	ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
	132	err = af_alg_wait_for_completion(crypto_ahash_final(&ctx->req),
	133	&ctx->completion);
	134	}
	135
	136	unlock:
	137	release_sock(sk);
	138
	139	return err ?: copied;
	140	}
	141
	142	static ssize_t hash_sendpage(struct socket sock, struct page page,
	143	int offset, size_t size, int flags)
	144	{
	145	struct sock *sk = sock->sk;
	146	struct alg_sock *ask = alg_sk(sk);
	147	struct hash_ctx *ctx = ask->private;
	148	int err;
	149
d3f7d56a SL	150	if (flags & MSG_SENDPAGE_NOTLAST)
	151	flags \|= MSG_MORE;
	152
fe869cdb HX	153	lock_sock(sk);
	154	sg_init_table(ctx->sgl.sg, 1);
	155	sg_set_page(ctx->sgl.sg, page, size, offset);
	156
493b2ed3 HX	157	if (!(flags & MSG_MORE)) {
	158	err = hash_alloc_result(sk, ctx);
	159	if (err)
	160	goto unlock;
	161	} else if (!ctx->more)
	162	hash_free_result(sk, ctx);
	163
fe869cdb HX	164	ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, ctx->result, size);
	165
	166	if (!(flags & MSG_MORE)) {
	167	if (ctx->more)
	168	err = crypto_ahash_finup(&ctx->req);
	169	else
	170	err = crypto_ahash_digest(&ctx->req);
	171	} else {
	172	if (!ctx->more) {
	173	err = crypto_ahash_init(&ctx->req);
fe097861	174	err = af_alg_wait_for_completion(err, &ctx->completion);
fe869cdb HX	175	if (err)
	176	goto unlock;
	177	}
	178
	179	err = crypto_ahash_update(&ctx->req);
	180	}
	181
	182	err = af_alg_wait_for_completion(err, &ctx->completion);
	183	if (err)
	184	goto unlock;
	185
	186	ctx->more = flags & MSG_MORE;
	187
	188	unlock:
	189	release_sock(sk);
	190
	191	return err ?: size;
	192	}
	193
1b784140 YX	194	static int hash_recvmsg(struct socket sock, struct msghdr msg, size_t len,
1b784140 YX	195	int flags)
fe869cdb HX	196	{
	197	struct sock *sk = sock->sk;
	198	struct alg_sock *ask = alg_sk(sk);
	199	struct hash_ctx *ctx = ask->private;
	200	unsigned ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
493b2ed3	201	bool result;
fe869cdb HX	202	int err;
	203
	204	if (len > ds)
	205	len = ds;
	206	else if (len < ds)
	207	msg->msg_flags \|= MSG_TRUNC;
	208
	209	lock_sock(sk);
493b2ed3 HX	210	result = ctx->result;
	211	err = hash_alloc_result(sk, ctx);
	212	if (err)
	213	goto unlock;
	214
	215	ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
	216
8acf7a10	217	if (!result && !ctx->more) {
a8348bca HX	218	err = af_alg_wait_for_completion(
	219	crypto_ahash_init(&ctx->req),
	220	&ctx->completion);
	221	if (err)
	222	goto unlock;
	223	}
	224
	225	if (!result \|\| ctx->more) {
fe869cdb	226	ctx->more = 0;
fe869cdb HX	227	err = af_alg_wait_for_completion(crypto_ahash_final(&ctx->req),
	228	&ctx->completion);
	229	if (err)
	230	goto unlock;
	231	}
	232
7eab8d9e	233	err = memcpy_to_msg(msg, ctx->result, len);
fe869cdb HX	234
fe869cdb HX	235	unlock:
a8348bca	236	hash_free_result(sk, ctx);
fe869cdb HX	237	release_sock(sk);
	238
	239	return err ?: len;
	240	}
	241
	242	static int hash_accept(struct socket sock, struct socket newsock, int flags)
	243	{
	244	struct sock *sk = sock->sk;
	245	struct alg_sock *ask = alg_sk(sk);
	246	struct hash_ctx *ctx = ask->private;
	247	struct ahash_request *req = &ctx->req;
51d32d32	248	char state[crypto_ahash_statesize(crypto_ahash_reqtfm(req)) ? : 1];
fe869cdb HX	249	struct sock *sk2;
	250	struct alg_sock *ask2;
	251	struct hash_ctx *ctx2;
4afa5f96	252	bool more;
fe869cdb HX	253	int err;
fe869cdb HX	254
4afa5f96 HX	255	lock_sock(sk);
	256	more = ctx->more;
	257	err = more ? crypto_ahash_export(req, state) : 0;
	258	release_sock(sk);
	259
fe869cdb HX	260	if (err)
	261	return err;
	262
	263	err = af_alg_accept(ask->parent, newsock);
	264	if (err)
	265	return err;
	266
	267	sk2 = newsock->sk;
	268	ask2 = alg_sk(sk2);
	269	ctx2 = ask2->private;
4afa5f96 HX	270	ctx2->more = more;
	271
	272	if (!more)
	273	return err;
fe869cdb HX	274
	275	err = crypto_ahash_import(&ctx2->req, state);
	276	if (err) {
	277	sock_orphan(sk2);
	278	sock_put(sk2);
	279	}
	280
	281	return err;
	282	}
	283
	284	static struct proto_ops algif_hash_ops = {
	285	.family = PF_ALG,
	286
	287	.connect = sock_no_connect,
	288	.socketpair = sock_no_socketpair,
	289	.getname = sock_no_getname,
	290	.ioctl = sock_no_ioctl,
	291	.listen = sock_no_listen,
	292	.shutdown = sock_no_shutdown,
	293	.getsockopt = sock_no_getsockopt,
	294	.mmap = sock_no_mmap,
	295	.bind = sock_no_bind,
	296	.setsockopt = sock_no_setsockopt,
	297	.poll = sock_no_poll,
	298
	299	.release = af_alg_release,
	300	.sendmsg = hash_sendmsg,
	301	.sendpage = hash_sendpage,
	302	.recvmsg = hash_recvmsg,
	303	.accept = hash_accept,
	304	};
	305
6de62f15 HX	306	static int hash_check_key(struct socket *sock)
6de62f15 HX	307	{
ad46d7e3	308	int err = 0;
6de62f15 HX	309	struct sock *psk;
	310	struct alg_sock *pask;
	311	struct algif_hash_tfm *tfm;
	312	struct sock *sk = sock->sk;
	313	struct alg_sock *ask = alg_sk(sk);
	314
ad46d7e3	315	lock_sock(sk);
6de62f15	316	if (ask->refcnt)
ad46d7e3	317	goto unlock_child;
6de62f15 HX	318
	319	psk = ask->parent;
	320	pask = alg_sk(ask->parent);
	321	tfm = pask->private;
	322
	323	err = -ENOKEY;
ad46d7e3	324	lock_sock_nested(psk, SINGLE_DEPTH_NESTING);
6de62f15 HX	325	if (!tfm->has_key)
	326	goto unlock;
	327
	328	if (!pask->refcnt++)
	329	sock_hold(psk);
	330
	331	ask->refcnt = 1;
	332	sock_put(psk);
	333
	334	err = 0;
	335
	336	unlock:
	337	release_sock(psk);
ad46d7e3 HX	338	unlock_child:
ad46d7e3 HX	339	release_sock(sk);
6de62f15 HX	340
	341	return err;
	342	}
	343
	344	static int hash_sendmsg_nokey(struct socket sock, struct msghdr msg,
	345	size_t size)
	346	{
	347	int err;
	348
	349	err = hash_check_key(sock);
	350	if (err)
	351	return err;
	352
	353	return hash_sendmsg(sock, msg, size);
	354	}
	355
	356	static ssize_t hash_sendpage_nokey(struct socket sock, struct page page,
	357	int offset, size_t size, int flags)
	358	{
	359	int err;
	360
	361	err = hash_check_key(sock);
	362	if (err)
	363	return err;
	364
	365	return hash_sendpage(sock, page, offset, size, flags);
	366	}
	367
	368	static int hash_recvmsg_nokey(struct socket sock, struct msghdr msg,
	369	size_t ignored, int flags)
	370	{
	371	int err;
	372
	373	err = hash_check_key(sock);
	374	if (err)
	375	return err;
	376
	377	return hash_recvmsg(sock, msg, ignored, flags);
	378	}
	379
	380	static int hash_accept_nokey(struct socket sock, struct socket newsock,
	381	int flags)
	382	{
	383	int err;
	384
	385	err = hash_check_key(sock);
	386	if (err)
	387	return err;
	388
	389	return hash_accept(sock, newsock, flags);
	390	}
	391
	392	static struct proto_ops algif_hash_ops_nokey = {
	393	.family = PF_ALG,
	394
	395	.connect = sock_no_connect,
	396	.socketpair = sock_no_socketpair,
	397	.getname = sock_no_getname,
	398	.ioctl = sock_no_ioctl,
	399	.listen = sock_no_listen,
	400	.shutdown = sock_no_shutdown,
	401	.getsockopt = sock_no_getsockopt,
	402	.mmap = sock_no_mmap,
	403	.bind = sock_no_bind,
404	.setsockopt = sock_no_setsockopt,
405	.poll = sock_no_poll,
406
407	.release = af_alg_release,
408	.sendmsg = hash_sendmsg_nokey,
409	.sendpage = hash_sendpage_nokey,
410	.recvmsg = hash_recvmsg_nokey,
411	.accept = hash_accept_nokey,
412	};
413
fe869cdb HX	414	static void hash_bind(const char name, u32 type, u32 mask)
fe869cdb HX	415	{
6de62f15 HX	416	struct algif_hash_tfm *tfm;
	417	struct crypto_ahash *hash;
	418
	419	tfm = kzalloc(sizeof(*tfm), GFP_KERNEL);
	420	if (!tfm)
	421	return ERR_PTR(-ENOMEM);
	422
	423	hash = crypto_alloc_ahash(name, type, mask);
	424	if (IS_ERR(hash)) {
	425	kfree(tfm);
	426	return ERR_CAST(hash);
	427	}
	428
	429	tfm->hash = hash;
	430
	431	return tfm;
fe869cdb HX	432	}
	433
	434	static void hash_release(void *private)
	435	{
6de62f15 HX	436	struct algif_hash_tfm *tfm = private;
	437
	438	crypto_free_ahash(tfm->hash);
	439	kfree(tfm);
fe869cdb HX	440	}
	441
	442	static int hash_setkey(void private, const u8 key, unsigned int keylen)
	443	{
6de62f15 HX	444	struct algif_hash_tfm *tfm = private;
	445	int err;
	446
	447	err = crypto_ahash_setkey(tfm->hash, key, keylen);
	448	tfm->has_key = !err;
	449
	450	return err;
fe869cdb HX	451	}
fe869cdb HX	452
f1d84af1	453	static void hash_sock_destruct(struct sock *sk)
fe869cdb HX	454	{
	455	struct alg_sock *ask = alg_sk(sk);
	456	struct hash_ctx *ctx = ask->private;
	457
493b2ed3	458	hash_free_result(sk, ctx);
fe869cdb	459	sock_kfree_s(sk, ctx, ctx->len);
6de62f15 HX	460	af_alg_release_parent(sk);
	461	}
	462
f1d84af1	463	static int hash_accept_parent_nokey(void private, struct sock sk)
fe869cdb HX	464	{
	465	struct hash_ctx *ctx;
	466	struct alg_sock *ask = alg_sk(sk);
6de62f15 HX	467	struct algif_hash_tfm *tfm = private;
	468	struct crypto_ahash *hash = tfm->hash;
	469	unsigned len = sizeof(*ctx) + crypto_ahash_reqsize(hash);
fe869cdb HX	470
	471	ctx = sock_kmalloc(sk, len, GFP_KERNEL);
	472	if (!ctx)
	473	return -ENOMEM;
	474
493b2ed3	475	ctx->result = NULL;
fe869cdb HX	476	ctx->len = len;
	477	ctx->more = 0;
	478	af_alg_init_completion(&ctx->completion);
	479
	480	ask->private = ctx;
	481
6de62f15	482	ahash_request_set_tfm(&ctx->req, hash);
fe869cdb HX	483	ahash_request_set_callback(&ctx->req, CRYPTO_TFM_REQ_MAY_BACKLOG,
	484	af_alg_complete, &ctx->completion);
	485
	486	sk->sk_destruct = hash_sock_destruct;
	487
	488	return 0;
	489	}
	490
6de62f15 HX	491	static int hash_accept_parent(void private, struct sock sk)
	492	{
	493	struct algif_hash_tfm *tfm = private;
	494
	495	if (!tfm->has_key && crypto_ahash_has_setkey(tfm->hash))
	496	return -ENOKEY;
	497
f1d84af1	498	return hash_accept_parent_nokey(private, sk);
6de62f15 HX	499	}
6de62f15 HX	500
fe869cdb HX	501	static const struct af_alg_type algif_type_hash = {
	502	.bind = hash_bind,
	503	.release = hash_release,
	504	.setkey = hash_setkey,
	505	.accept = hash_accept_parent,
6de62f15	506	.accept_nokey = hash_accept_parent_nokey,
fe869cdb	507	.ops = &algif_hash_ops,
6de62f15	508	.ops_nokey = &algif_hash_ops_nokey,
fe869cdb HX	509	.name = "hash",
	510	.owner = THIS_MODULE
	511	};
	512
	513	static int __init algif_hash_init(void)
	514	{
	515	return af_alg_register_type(&algif_type_hash);
	516	}
	517
	518	static void __exit algif_hash_exit(void)
	519	{
	520	int err = af_alg_unregister_type(&algif_type_hash);
	521	BUG_ON(err);
	522	}
	523
	524	module_init(algif_hash_init);
	525	module_exit(algif_hash_exit);
	526	MODULE_LICENSE("GPL");