[linux.git] / crypto / algif_hash.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * algif_hash: User-space interface for hash algorithms
 *
 * This file provides the user-space API for hash algorithms.
 *
 * Copyright (c) 2010 Herbert Xu <[email protected]>
 */

#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 crypto_wait wait;

	unsigned int len;
	bool more;

	struct ahash_request req;
};

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)
{
	struct sock *sk = sock->sk;
	struct alg_sock *ask = alg_sk(sk);
	struct hash_ctx *ctx = ask->private;
	ssize_t copied = 0;
	size_t len, max_pages, npages;
	bool continuing, need_init = false;
	int err;

	max_pages = min_t(size_t, ALG_MAX_PAGES,
			  DIV_ROUND_UP(sk->sk_sndbuf, PAGE_SIZE));

	lock_sock(sk);
	continuing = ctx->more;

	if (!continuing) {
		/* Discard a previous request that wasn't marked MSG_MORE. */
		hash_free_result(sk, ctx);
		if (!msg_data_left(msg))
			goto done; /* Zero-length; don't start new req */
		need_init = true;
	} else if (!msg_data_left(msg)) {
		/*
		 * No data - finalise the prev req if MSG_MORE so any error
		 * comes out here.
		 */
		if (!(msg->msg_flags & MSG_MORE)) {
			err = hash_alloc_result(sk, ctx);
			if (err)
				goto unlock_free_result;
			ahash_request_set_crypt(&ctx->req, NULL,
						ctx->result, 0);
			err = crypto_wait_req(crypto_ahash_final(&ctx->req),
					      &ctx->wait);
			if (err)
				goto unlock_free_result;
		}
		goto done_more;
	}

	while (msg_data_left(msg)) {
		ctx->sgl.sgt.sgl = ctx->sgl.sgl;
		ctx->sgl.sgt.nents = 0;
		ctx->sgl.sgt.orig_nents = 0;

		err = -EIO;
		npages = iov_iter_npages(&msg->msg_iter, max_pages);
		if (npages == 0)
			goto unlock_free;

		sg_init_table(ctx->sgl.sgl, npages);

		ctx->sgl.need_unpin = iov_iter_extract_will_pin(&msg->msg_iter);

		err = extract_iter_to_sg(&msg->msg_iter, LONG_MAX,
					 &ctx->sgl.sgt, npages, 0);
		if (err < 0)
			goto unlock_free;
		len = err;
		sg_mark_end(ctx->sgl.sgt.sgl + ctx->sgl.sgt.nents - 1);

		if (!msg_data_left(msg)) {
			err = hash_alloc_result(sk, ctx);
			if (err)
				goto unlock_free;
		}

		ahash_request_set_crypt(&ctx->req, ctx->sgl.sgt.sgl,
					ctx->result, len);

		if (!msg_data_left(msg) && !continuing &&
		    !(msg->msg_flags & MSG_MORE)) {
			err = crypto_ahash_digest(&ctx->req);
		} else {
			if (need_init) {
				err = crypto_wait_req(
					crypto_ahash_init(&ctx->req),
					&ctx->wait);
				if (err)
					goto unlock_free;
				need_init = false;
			}

			if (msg_data_left(msg) || (msg->msg_flags & MSG_MORE))
				err = crypto_ahash_update(&ctx->req);
			else
				err = crypto_ahash_finup(&ctx->req);
			continuing = true;
		}

		err = crypto_wait_req(err, &ctx->wait);
		if (err)
			goto unlock_free;

		copied += len;
		af_alg_free_sg(&ctx->sgl);
	}

done_more:
	ctx->more = msg->msg_flags & MSG_MORE;
done:
	err = 0;
unlock:
	release_sock(sk);
	return copied ?: err;

unlock_free:
	af_alg_free_sg(&ctx->sgl);
unlock_free_result:
	hash_free_result(sk, ctx);
	ctx->more = false;
	goto unlock;
}

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

	if (!result || ctx->more) {
		ctx->more = false;
		err = crypto_wait_req(crypto_ahash_final(&ctx->req),
				      &ctx->wait);
		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,
		       struct proto_accept_arg *arg)
{
	struct sock *sk = sock->sk;
	struct alg_sock *ask = alg_sk(sk);
	struct hash_ctx *ctx = ask->private;
	struct ahash_request *req = &ctx->req;
	struct crypto_ahash *tfm;
	struct sock *sk2;
	struct alg_sock *ask2;
	struct hash_ctx *ctx2;
	char *state;
	bool more;
	int err;

	tfm = crypto_ahash_reqtfm(req);
	state = kmalloc(crypto_ahash_statesize(tfm), GFP_KERNEL);
	err = -ENOMEM;
	if (!state)
		goto out;

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

	if (err)
		goto out_free_state;

	err = af_alg_accept(ask->parent, newsock, arg);
	if (err)
		goto out_free_state;

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

	if (!more)
		goto out_free_state;

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

out_free_state:
	kfree_sensitive(state);

out:
	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,
	.mmap		=	sock_no_mmap,
	.bind		=	sock_no_bind,

	.release	=	af_alg_release,
	.sendmsg	=	hash_sendmsg,
	.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 crypto_ahash *tfm;
	struct sock *sk = sock->sk;
	struct alg_sock *ask = alg_sk(sk);

	lock_sock(sk);
	if (!atomic_read(&ask->nokey_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 (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
		goto unlock;

	atomic_dec(&pask->nokey_refcnt);
	atomic_set(&ask->nokey_refcnt, 0);

	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 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,
			     struct proto_accept_arg *arg)
{
	int err;

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

	return hash_accept(sock, newsock, arg);
}

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,
	.mmap		=	sock_no_mmap,
	.bind		=	sock_no_bind,

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

static void *hash_bind(const char *name, u32 type, u32 mask)
{
	return crypto_alloc_ahash(name, type, mask);
}

static void hash_release(void *private)
{
	crypto_free_ahash(private);
}

static int hash_setkey(void *private, const u8 *key, unsigned int keylen)
{
	return crypto_ahash_setkey(private, key, keylen);
}

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 crypto_ahash *tfm = private;
	struct alg_sock *ask = alg_sk(sk);
	struct hash_ctx *ctx;
	unsigned int len = sizeof(*ctx) + crypto_ahash_reqsize(tfm);

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

	ctx->result = NULL;
	ctx->len = len;
	ctx->more = false;
	crypto_init_wait(&ctx->wait);

	ask->private = ctx;

	ahash_request_set_tfm(&ctx->req, tfm);
	ahash_request_set_callback(&ctx->req, CRYPTO_TFM_REQ_MAY_BACKLOG,
				   crypto_req_done, &ctx->wait);

	sk->sk_destruct = hash_sock_destruct;

	return 0;
}

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

	if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
		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_DESCRIPTION("Userspace interface for hash algorithms");
MODULE_LICENSE("GPL");
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
fe869cdb HX	2	/*
	3	* algif_hash: User-space interface for hash algorithms
	4	*
	5	* This file provides the user-space API for hash algorithms.
	6	*
	7	* Copyright (c) 2010 Herbert Xu <[email protected]>
fe869cdb HX	8	*/
	9
	10	#include <crypto/hash.h>
	11	#include <crypto/if_alg.h>
	12	#include <linux/init.h>
	13	#include <linux/kernel.h>
	14	#include <linux/mm.h>
	15	#include <linux/module.h>
	16	#include <linux/net.h>
	17	#include <net/sock.h>
	18
	19	struct hash_ctx {
	20	struct af_alg_sgl sgl;
	21
	22	u8 *result;
	23
2c3f8b16	24	struct crypto_wait wait;
fe869cdb HX	25
	26	unsigned int len;
	27	bool more;
	28
	29	struct ahash_request req;
	30	};
	31
493b2ed3 HX	32	static int hash_alloc_result(struct sock sk, struct hash_ctx ctx)
	33	{
	34	unsigned ds;
	35
	36	if (ctx->result)
	37	return 0;
	38
	39	ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
	40
	41	ctx->result = sock_kmalloc(sk, ds, GFP_KERNEL);
	42	if (!ctx->result)
	43	return -ENOMEM;
	44
	45	memset(ctx->result, 0, ds);
	46
	47	return 0;
	48	}
	49
	50	static void hash_free_result(struct sock sk, struct hash_ctx ctx)
	51	{
	52	unsigned ds;
	53
	54	if (!ctx->result)
	55	return;
	56
	57	ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
	58
	59	sock_kzfree_s(sk, ctx->result, ds);
	60	ctx->result = NULL;
	61	}
	62
1b784140 YX	63	static int hash_sendmsg(struct socket sock, struct msghdr msg,
1b784140 YX	64	size_t ignored)
fe869cdb	65	{
fe869cdb HX	66	struct sock *sk = sock->sk;
	67	struct alg_sock *ask = alg_sk(sk);
	68	struct hash_ctx *ctx = ask->private;
c662b043 DH	69	ssize_t copied = 0;
c662b043 DH	70	size_t len, max_pages, npages;
0b7ec177	71	bool continuing, need_init = false;
fe869cdb HX	72	int err;
fe869cdb HX	73
c662b043 DH	74	max_pages = min_t(size_t, ALG_MAX_PAGES,
c662b043 DH	75	DIV_ROUND_UP(sk->sk_sndbuf, PAGE_SIZE));
fe869cdb HX	76
fe869cdb HX	77	lock_sock(sk);
0b7ec177 DH	78	continuing = ctx->more;
0b7ec177 DH	79
c662b043	80	if (!continuing) {
b6d972f6 DH	81	/* Discard a previous request that wasn't marked MSG_MORE. */
	82	hash_free_result(sk, ctx);
	83	if (!msg_data_left(msg))
	84	goto done; /* Zero-length; don't start new req */
c662b043	85	need_init = true;
b6d972f6 DH	86	} else if (!msg_data_left(msg)) {
	87	/*
	88	* No data - finalise the prev req if MSG_MORE so any error
	89	* comes out here.
	90	*/
	91	if (!(msg->msg_flags & MSG_MORE)) {
	92	err = hash_alloc_result(sk, ctx);
	93	if (err)
24c890dd	94	goto unlock_free_result;
b6d972f6 DH	95	ahash_request_set_crypt(&ctx->req, NULL,
	96	ctx->result, 0);
	97	err = crypto_wait_req(crypto_ahash_final(&ctx->req),
	98	&ctx->wait);
	99	if (err)
24c890dd	100	goto unlock_free_result;
b6d972f6 DH	101	}
b6d972f6 DH	102	goto done_more;
fe869cdb HX	103	}
fe869cdb HX	104
01e97e65	105	while (msg_data_left(msg)) {
c1abe6f5 DH	106	ctx->sgl.sgt.sgl = ctx->sgl.sgl;
	107	ctx->sgl.sgt.nents = 0;
	108	ctx->sgl.sgt.orig_nents = 0;
	109
c662b043 DH	110	err = -EIO;
	111	npages = iov_iter_npages(&msg->msg_iter, max_pages);
	112	if (npages == 0)
	113	goto unlock_free;
	114
c662b043	115	sg_init_table(ctx->sgl.sgl, npages);
c1abe6f5 DH	116
c1abe6f5 DH	117	ctx->sgl.need_unpin = iov_iter_extract_will_pin(&msg->msg_iter);
fe869cdb	118
c662b043 DH	119	err = extract_iter_to_sg(&msg->msg_iter, LONG_MAX,
	120	&ctx->sgl.sgt, npages, 0);
	121	if (err < 0)
	122	goto unlock_free;
	123	len = err;
	124	sg_mark_end(ctx->sgl.sgt.sgl + ctx->sgl.sgt.nents - 1);
	125
	126	if (!msg_data_left(msg)) {
	127	err = hash_alloc_result(sk, ctx);
	128	if (err)
	129	goto unlock_free;
dc5801f6	130	}
fe869cdb	131
c662b043 DH	132	ahash_request_set_crypt(&ctx->req, ctx->sgl.sgt.sgl,
	133	ctx->result, len);
	134
	135	if (!msg_data_left(msg) && !continuing &&
	136	!(msg->msg_flags & MSG_MORE)) {
	137	err = crypto_ahash_digest(&ctx->req);
	138	} else {
	139	if (need_init) {
	140	err = crypto_wait_req(
	141	crypto_ahash_init(&ctx->req),
	142	&ctx->wait);
	143	if (err)
	144	goto unlock_free;
	145	need_init = false;
	146	}
	147
	148	if (msg_data_left(msg) \|\| (msg->msg_flags & MSG_MORE))
	149	err = crypto_ahash_update(&ctx->req);
	150	else
	151	err = crypto_ahash_finup(&ctx->req);
	152	continuing = true;
	153	}
fe869cdb	154
c662b043	155	err = crypto_wait_req(err, &ctx->wait);
493b2ed3	156	if (err)
c662b043	157	goto unlock_free;
493b2ed3	158
c662b043 DH	159	copied += len;
c662b043 DH	160	af_alg_free_sg(&ctx->sgl);
fe869cdb HX	161	}
fe869cdb HX	162
b6d972f6	163	done_more:
c662b043	164	ctx->more = msg->msg_flags & MSG_MORE;
b6d972f6	165	done:
c662b043	166	err = 0;
fe869cdb HX	167	unlock:
fe869cdb HX	168	release_sock(sk);
c662b043	169	return copied ?: err;
fe869cdb	170
c662b043 DH	171	unlock_free:
c662b043 DH	172	af_alg_free_sg(&ctx->sgl);
24c890dd	173	unlock_free_result:
b6d972f6 DH	174	hash_free_result(sk, ctx);
b6d972f6 DH	175	ctx->more = false;
c662b043	176	goto unlock;
fe869cdb HX	177	}
fe869cdb HX	178
1b784140 YX	179	static int hash_recvmsg(struct socket sock, struct msghdr msg, size_t len,
1b784140 YX	180	int flags)
fe869cdb HX	181	{
	182	struct sock *sk = sock->sk;
	183	struct alg_sock *ask = alg_sk(sk);
	184	struct hash_ctx *ctx = ask->private;
	185	unsigned ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
493b2ed3	186	bool result;
fe869cdb HX	187	int err;
	188
	189	if (len > ds)
	190	len = ds;
	191	else if (len < ds)
	192	msg->msg_flags \|= MSG_TRUNC;
	193
	194	lock_sock(sk);
493b2ed3 HX	195	result = ctx->result;
	196	err = hash_alloc_result(sk, ctx);
	197	if (err)
	198	goto unlock;
	199
	200	ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
	201
8acf7a10	202	if (!result && !ctx->more) {
2c3f8b16 GBY	203	err = crypto_wait_req(crypto_ahash_init(&ctx->req),
2c3f8b16 GBY	204	&ctx->wait);
a8348bca HX	205	if (err)
	206	goto unlock;
	207	}
	208
	209	if (!result \|\| ctx->more) {
fcb90d51	210	ctx->more = false;
2c3f8b16 GBY	211	err = crypto_wait_req(crypto_ahash_final(&ctx->req),
2c3f8b16 GBY	212	&ctx->wait);
fe869cdb HX	213	if (err)
	214	goto unlock;
	215	}
	216
7eab8d9e	217	err = memcpy_to_msg(msg, ctx->result, len);
fe869cdb HX	218
fe869cdb HX	219	unlock:
a8348bca	220	hash_free_result(sk, ctx);
fe869cdb HX	221	release_sock(sk);
	222
	223	return err ?: len;
	224	}
	225
92ef0fd5 JA	226	static int hash_accept(struct socket sock, struct socket newsock,
92ef0fd5 JA	227	struct proto_accept_arg *arg)
fe869cdb HX	228	{
	229	struct sock *sk = sock->sk;
	230	struct alg_sock *ask = alg_sk(sk);
	231	struct hash_ctx *ctx = ask->private;
	232	struct ahash_request *req = &ctx->req;
acc03d89	233	struct crypto_ahash *tfm;
fe869cdb HX	234	struct sock *sk2;
	235	struct alg_sock *ask2;
	236	struct hash_ctx *ctx2;
acc03d89	237	char *state;
4afa5f96	238	bool more;
fe869cdb HX	239	int err;
fe869cdb HX	240
acc03d89 HX	241	tfm = crypto_ahash_reqtfm(req);
	242	state = kmalloc(crypto_ahash_statesize(tfm), GFP_KERNEL);
	243	err = -ENOMEM;
	244	if (!state)
	245	goto out;
	246
4afa5f96 HX	247	lock_sock(sk);
	248	more = ctx->more;
	249	err = more ? crypto_ahash_export(req, state) : 0;
	250	release_sock(sk);
	251
fe869cdb	252	if (err)
acc03d89	253	goto out_free_state;
fe869cdb	254
92ef0fd5	255	err = af_alg_accept(ask->parent, newsock, arg);
fe869cdb	256	if (err)
acc03d89	257	goto out_free_state;
fe869cdb HX	258
	259	sk2 = newsock->sk;
	260	ask2 = alg_sk(sk2);
	261	ctx2 = ask2->private;
4afa5f96 HX	262	ctx2->more = more;
	263
	264	if (!more)
acc03d89	265	goto out_free_state;
fe869cdb HX	266
	267	err = crypto_ahash_import(&ctx2->req, state);
	268	if (err) {
	269	sock_orphan(sk2);
	270	sock_put(sk2);
	271	}
	272
acc03d89 HX	273	out_free_state:
	274	kfree_sensitive(state);
	275
	276	out:
fe869cdb HX	277	return err;
	278	}
	279
	280	static struct proto_ops algif_hash_ops = {
	281	.family = PF_ALG,
	282
	283	.connect = sock_no_connect,
	284	.socketpair = sock_no_socketpair,
	285	.getname = sock_no_getname,
	286	.ioctl = sock_no_ioctl,
	287	.listen = sock_no_listen,
	288	.shutdown = sock_no_shutdown,
fe869cdb HX	289	.mmap = sock_no_mmap,
fe869cdb HX	290	.bind = sock_no_bind,
fe869cdb HX	291
	292	.release = af_alg_release,
	293	.sendmsg = hash_sendmsg,
fe869cdb HX	294	.recvmsg = hash_recvmsg,
	295	.accept = hash_accept,
	296	};
	297
6de62f15 HX	298	static int hash_check_key(struct socket *sock)
6de62f15 HX	299	{
ad46d7e3	300	int err = 0;
6de62f15 HX	301	struct sock *psk;
6de62f15 HX	302	struct alg_sock *pask;
9fa68f62	303	struct crypto_ahash *tfm;
6de62f15 HX	304	struct sock *sk = sock->sk;
	305	struct alg_sock *ask = alg_sk(sk);
	306
ad46d7e3	307	lock_sock(sk);
34c86f4c	308	if (!atomic_read(&ask->nokey_refcnt))
ad46d7e3	309	goto unlock_child;
6de62f15 HX	310
	311	psk = ask->parent;
	312	pask = alg_sk(ask->parent);
	313	tfm = pask->private;
	314
	315	err = -ENOKEY;
ad46d7e3	316	lock_sock_nested(psk, SINGLE_DEPTH_NESTING);
9fa68f62	317	if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
6de62f15 HX	318	goto unlock;
6de62f15 HX	319
34c86f4c HX	320	atomic_dec(&pask->nokey_refcnt);
34c86f4c HX	321	atomic_set(&ask->nokey_refcnt, 0);
6de62f15 HX	322
	323	err = 0;
	324
	325	unlock:
	326	release_sock(psk);
ad46d7e3 HX	327	unlock_child:
ad46d7e3 HX	328	release_sock(sk);
6de62f15 HX	329
	330	return err;
	331	}
	332
	333	static int hash_sendmsg_nokey(struct socket sock, struct msghdr msg,
	334	size_t size)
	335	{
	336	int err;
	337
	338	err = hash_check_key(sock);
	339	if (err)
	340	return err;
	341
	342	return hash_sendmsg(sock, msg, size);
	343	}
	344
6de62f15 HX	345	static int hash_recvmsg_nokey(struct socket sock, struct msghdr msg,
	346	size_t ignored, int flags)
	347	{
	348	int err;
	349
	350	err = hash_check_key(sock);
	351	if (err)
	352	return err;
	353
	354	return hash_recvmsg(sock, msg, ignored, flags);
	355	}
	356
	357	static int hash_accept_nokey(struct socket sock, struct socket newsock,
92ef0fd5	358	struct proto_accept_arg *arg)
6de62f15 HX	359	{
	360	int err;
	361
	362	err = hash_check_key(sock);
	363	if (err)
	364	return err;
	365
92ef0fd5	366	return hash_accept(sock, newsock, arg);
6de62f15 HX	367	}
	368
	369	static struct proto_ops algif_hash_ops_nokey = {
	370	.family = PF_ALG,
	371
	372	.connect = sock_no_connect,
	373	.socketpair = sock_no_socketpair,
	374	.getname = sock_no_getname,
	375	.ioctl = sock_no_ioctl,
	376	.listen = sock_no_listen,
	377	.shutdown = sock_no_shutdown,
6de62f15 HX	378	.mmap = sock_no_mmap,
6de62f15 HX	379	.bind = sock_no_bind,
6de62f15 HX	380
	381	.release = af_alg_release,
	382	.sendmsg = hash_sendmsg_nokey,
6de62f15 HX	383	.recvmsg = hash_recvmsg_nokey,
	384	.accept = hash_accept_nokey,
	385	};
	386
fe869cdb HX	387	static void hash_bind(const char name, u32 type, u32 mask)
fe869cdb HX	388	{
9fa68f62	389	return crypto_alloc_ahash(name, type, mask);
fe869cdb HX	390	}
	391
	392	static void hash_release(void *private)
	393	{
9fa68f62	394	crypto_free_ahash(private);
fe869cdb HX	395	}
	396
	397	static int hash_setkey(void private, const u8 key, unsigned int keylen)
	398	{
9fa68f62	399	return crypto_ahash_setkey(private, key, keylen);
fe869cdb HX	400	}
fe869cdb HX	401
f1d84af1	402	static void hash_sock_destruct(struct sock *sk)
fe869cdb HX	403	{
	404	struct alg_sock *ask = alg_sk(sk);
	405	struct hash_ctx *ctx = ask->private;
	406
493b2ed3	407	hash_free_result(sk, ctx);
fe869cdb	408	sock_kfree_s(sk, ctx, ctx->len);
6de62f15 HX	409	af_alg_release_parent(sk);
	410	}
	411
f1d84af1	412	static int hash_accept_parent_nokey(void private, struct sock sk)
fe869cdb	413	{
9fa68f62	414	struct crypto_ahash *tfm = private;
fe869cdb	415	struct alg_sock *ask = alg_sk(sk);
9fa68f62 EB	416	struct hash_ctx *ctx;
9fa68f62 EB	417	unsigned int len = sizeof(*ctx) + crypto_ahash_reqsize(tfm);
fe869cdb HX	418
	419	ctx = sock_kmalloc(sk, len, GFP_KERNEL);
	420	if (!ctx)
	421	return -ENOMEM;
	422
493b2ed3	423	ctx->result = NULL;
fe869cdb	424	ctx->len = len;
fcb90d51	425	ctx->more = false;
2c3f8b16	426	crypto_init_wait(&ctx->wait);
fe869cdb HX	427
	428	ask->private = ctx;
	429
9fa68f62	430	ahash_request_set_tfm(&ctx->req, tfm);
fe869cdb	431	ahash_request_set_callback(&ctx->req, CRYPTO_TFM_REQ_MAY_BACKLOG,
2c3f8b16	432	crypto_req_done, &ctx->wait);
fe869cdb HX	433
	434	sk->sk_destruct = hash_sock_destruct;
	435
	436	return 0;
	437	}
	438
6de62f15 HX	439	static int hash_accept_parent(void private, struct sock sk)
6de62f15 HX	440	{
9fa68f62	441	struct crypto_ahash *tfm = private;
6de62f15	442
9fa68f62	443	if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
6de62f15 HX	444	return -ENOKEY;
6de62f15 HX	445
f1d84af1	446	return hash_accept_parent_nokey(private, sk);
6de62f15 HX	447	}
6de62f15 HX	448
fe869cdb HX	449	static const struct af_alg_type algif_type_hash = {
	450	.bind = hash_bind,
	451	.release = hash_release,
	452	.setkey = hash_setkey,
	453	.accept = hash_accept_parent,
6de62f15	454	.accept_nokey = hash_accept_parent_nokey,
fe869cdb	455	.ops = &algif_hash_ops,
6de62f15	456	.ops_nokey = &algif_hash_ops_nokey,
fe869cdb HX	457	.name = "hash",
	458	.owner = THIS_MODULE
	459	};
	460
	461	static int __init algif_hash_init(void)
	462	{
	463	return af_alg_register_type(&algif_type_hash);
	464	}
	465
	466	static void __exit algif_hash_exit(void)
	467	{
	468	int err = af_alg_unregister_type(&algif_type_hash);
	469	BUG_ON(err);
	470	}
	471
	472	module_init(algif_hash_init);
	473	module_exit(algif_hash_exit);
7c699fe9	474	MODULE_DESCRIPTION("Userspace interface for hash algorithms");
fe869cdb	475	MODULE_LICENSE("GPL");