[mirror_ubuntu-bionic-kernel.git] / crypto / algif_skcipher.c

/*
 * algif_skcipher: User-space interface for skcipher algorithms
 *
 * This file provides the user-space API for symmetric key ciphers.
 *
 * 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.
 *
 * The following concept of the memory management is used:
 *
 * The kernel maintains two SGLs, the TX SGL and the RX SGL. The TX SGL is
 * filled by user space with the data submitted via sendpage/sendmsg. Filling
 * up the TX SGL does not cause a crypto operation -- the data will only be
 * tracked by the kernel. Upon receipt of one recvmsg call, the caller must
 * provide a buffer which is tracked with the RX SGL.
 *
 * During the processing of the recvmsg operation, the cipher request is
 * allocated and prepared. As part of the recvmsg operation, the processed
 * TX buffers are extracted from the TX SGL into a separate SGL.
 *
 * After the completion of the crypto operation, the RX SGL and the cipher
 * request is released. The extracted TX SGL parts are released together with
 * the RX SGL release.
 */

#include <crypto/scatterwalk.h>
#include <crypto/skcipher.h>
#include <crypto/if_alg.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/net.h>
#include <net/sock.h>

struct skcipher_tfm {
	struct crypto_skcipher *skcipher;
	bool has_key;
};

static int skcipher_sendmsg(struct socket *sock, struct msghdr *msg,
			    size_t size)
{
	struct sock *sk = sock->sk;
	struct alg_sock *ask = alg_sk(sk);
	struct sock *psk = ask->parent;
	struct alg_sock *pask = alg_sk(psk);
	struct skcipher_tfm *skc = pask->private;
	struct crypto_skcipher *tfm = skc->skcipher;
	unsigned ivsize = crypto_skcipher_ivsize(tfm);

	return af_alg_sendmsg(sock, msg, size, ivsize);
}

static int _skcipher_recvmsg(struct socket *sock, struct msghdr *msg,
			     size_t ignored, int flags)
{
	struct sock *sk = sock->sk;
	struct alg_sock *ask = alg_sk(sk);
	struct sock *psk = ask->parent;
	struct alg_sock *pask = alg_sk(psk);
	struct af_alg_ctx *ctx = ask->private;
	struct skcipher_tfm *skc = pask->private;
	struct crypto_skcipher *tfm = skc->skcipher;
	unsigned int bs = crypto_skcipher_blocksize(tfm);
	struct af_alg_async_req *areq;
	int err = 0;
	size_t len = 0;

	/* Allocate cipher request for current operation. */
	areq = af_alg_alloc_areq(sk, sizeof(struct af_alg_async_req) +
				     crypto_skcipher_reqsize(tfm));
	if (IS_ERR(areq))
		return PTR_ERR(areq);

	/* convert iovecs of output buffers into RX SGL */
	err = af_alg_get_rsgl(sk, msg, flags, areq, -1, &len);
	if (err)
		goto free;

	/* Process only as much RX buffers for which we have TX data */
	if (len > ctx->used)
		len = ctx->used;

	/*
	 * If more buffers are to be expected to be processed, process only
	 * full block size buffers.
	 */
	if (ctx->more || len < ctx->used)
		len -= len % bs;

	/*
	 * Create a per request TX SGL for this request which tracks the
	 * SG entries from the global TX SGL.
	 */
	areq->tsgl_entries = af_alg_count_tsgl(sk, len, 0);
	if (!areq->tsgl_entries)
		areq->tsgl_entries = 1;
	areq->tsgl = sock_kmalloc(sk, sizeof(*areq->tsgl) * areq->tsgl_entries,
				  GFP_KERNEL);
	if (!areq->tsgl) {
		err = -ENOMEM;
		goto free;
	}
	sg_init_table(areq->tsgl, areq->tsgl_entries);
	af_alg_pull_tsgl(sk, len, areq->tsgl, 0);

	/* Initialize the crypto operation */
	skcipher_request_set_tfm(&areq->cra_u.skcipher_req, tfm);
	skcipher_request_set_crypt(&areq->cra_u.skcipher_req, areq->tsgl,
				   areq->first_rsgl.sgl.sg, len, ctx->iv);

	if (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) {
		/* AIO operation */
		sock_hold(sk);
		areq->iocb = msg->msg_iocb;
		skcipher_request_set_callback(&areq->cra_u.skcipher_req,
					      CRYPTO_TFM_REQ_MAY_SLEEP,
					      af_alg_async_cb, areq);
		err = ctx->enc ?
			crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) :
			crypto_skcipher_decrypt(&areq->cra_u.skcipher_req);

		/* AIO operation in progress */
		if (err == -EINPROGRESS || err == -EBUSY) {
			/* Remember output size that will be generated. */
			areq->outlen = len;

			return -EIOCBQUEUED;
		}

		sock_put(sk);
	} else {
		/* Synchronous operation */
		skcipher_request_set_callback(&areq->cra_u.skcipher_req,
					      CRYPTO_TFM_REQ_MAY_SLEEP |
					      CRYPTO_TFM_REQ_MAY_BACKLOG,
					      crypto_req_done, &ctx->wait);
		err = crypto_wait_req(ctx->enc ?
			crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) :
			crypto_skcipher_decrypt(&areq->cra_u.skcipher_req),
						 &ctx->wait);
	}


free:
	af_alg_free_resources(areq);

	return err ? err : len;
}

static int skcipher_recvmsg(struct socket *sock, struct msghdr *msg,
			    size_t ignored, int flags)
{
	struct sock *sk = sock->sk;
	int ret = 0;

	lock_sock(sk);
	while (msg_data_left(msg)) {
		int err = _skcipher_recvmsg(sock, msg, ignored, flags);

		/*
		 * This error covers -EIOCBQUEUED which implies that we can
		 * only handle one AIO request. If the caller wants to have
		 * multiple AIO requests in parallel, he must make multiple
		 * separate AIO calls.
		 *
		 * Also return the error if no data has been processed so far.
		 */
		if (err <= 0) {
			if (err == -EIOCBQUEUED || !ret)
				ret = err;
			goto out;
		}

		ret += err;
	}

out:
	af_alg_wmem_wakeup(sk);
	release_sock(sk);
	return ret;
}


static struct proto_ops algif_skcipher_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,
	.accept		=	sock_no_accept,
	.setsockopt	=	sock_no_setsockopt,

	.release	=	af_alg_release,
	.sendmsg	=	skcipher_sendmsg,
	.sendpage	=	af_alg_sendpage,
	.recvmsg	=	skcipher_recvmsg,
	.poll		=	af_alg_poll,
};

static int skcipher_check_key(struct socket *sock)
{
	int err = 0;
	struct sock *psk;
	struct alg_sock *pask;
	struct skcipher_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 skcipher_sendmsg_nokey(struct socket *sock, struct msghdr *msg,
				  size_t size)
{
	int err;

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

	return skcipher_sendmsg(sock, msg, size);
}

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

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

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

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

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

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

static struct proto_ops algif_skcipher_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,
	.accept		=	sock_no_accept,
	.setsockopt	=	sock_no_setsockopt,

	.release	=	af_alg_release,
	.sendmsg	=	skcipher_sendmsg_nokey,
	.sendpage	=	skcipher_sendpage_nokey,
	.recvmsg	=	skcipher_recvmsg_nokey,
	.poll		=	af_alg_poll,
};

static void *skcipher_bind(const char *name, u32 type, u32 mask)
{
	struct skcipher_tfm *tfm;
	struct crypto_skcipher *skcipher;

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

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

	tfm->skcipher = skcipher;

	return tfm;
}

static void skcipher_release(void *private)
{
	struct skcipher_tfm *tfm = private;

	crypto_free_skcipher(tfm->skcipher);
	kfree(tfm);
}

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

	err = crypto_skcipher_setkey(tfm->skcipher, key, keylen);
	tfm->has_key = !err;

	return err;
}

static void skcipher_sock_destruct(struct sock *sk)
{
	struct alg_sock *ask = alg_sk(sk);
	struct af_alg_ctx *ctx = ask->private;
	struct sock *psk = ask->parent;
	struct alg_sock *pask = alg_sk(psk);
	struct skcipher_tfm *skc = pask->private;
	struct crypto_skcipher *tfm = skc->skcipher;

	af_alg_pull_tsgl(sk, ctx->used, NULL, 0);
	sock_kzfree_s(sk, ctx->iv, crypto_skcipher_ivsize(tfm));
	sock_kfree_s(sk, ctx, ctx->len);
	af_alg_release_parent(sk);
}

static int skcipher_accept_parent_nokey(void *private, struct sock *sk)
{
	struct af_alg_ctx *ctx;
	struct alg_sock *ask = alg_sk(sk);
	struct skcipher_tfm *tfm = private;
	struct crypto_skcipher *skcipher = tfm->skcipher;
	unsigned int len = sizeof(*ctx);

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

	ctx->iv = sock_kmalloc(sk, crypto_skcipher_ivsize(skcipher),
			       GFP_KERNEL);
	if (!ctx->iv) {
		sock_kfree_s(sk, ctx, len);
		return -ENOMEM;
	}

	memset(ctx->iv, 0, crypto_skcipher_ivsize(skcipher));

	INIT_LIST_HEAD(&ctx->tsgl_list);
	ctx->len = len;
	ctx->used = 0;
	ctx->rcvused = 0;
	ctx->more = 0;
	ctx->merge = 0;
	ctx->enc = 0;
	crypto_init_wait(&ctx->wait);

	ask->private = ctx;

	sk->sk_destruct = skcipher_sock_destruct;

	return 0;
}

static int skcipher_accept_parent(void *private, struct sock *sk)
{
	struct skcipher_tfm *tfm = private;

	if (!tfm->has_key && crypto_skcipher_has_setkey(tfm->skcipher))
		return -ENOKEY;

	return skcipher_accept_parent_nokey(private, sk);
}

static const struct af_alg_type algif_type_skcipher = {
	.bind		=	skcipher_bind,
	.release	=	skcipher_release,
	.setkey		=	skcipher_setkey,
	.accept		=	skcipher_accept_parent,
	.accept_nokey	=	skcipher_accept_parent_nokey,
	.ops		=	&algif_skcipher_ops,
	.ops_nokey	=	&algif_skcipher_ops_nokey,
	.name		=	"skcipher",
	.owner		=	THIS_MODULE
};

static int __init algif_skcipher_init(void)
{
	return af_alg_register_type(&algif_type_skcipher);
}

static void __exit algif_skcipher_exit(void)
{
	int err = af_alg_unregister_type(&algif_type_skcipher);
	BUG_ON(err);
}

module_init(algif_skcipher_init);
module_exit(algif_skcipher_exit);
MODULE_LICENSE("GPL");
Commit	Line	Data
8ff59090 HX	1	/*
	2	* algif_skcipher: User-space interface for skcipher algorithms
	3	*
	4	* This file provides the user-space API for symmetric key ciphers.
	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	*
e870456d SM	13	* The following concept of the memory management is used:
	14	*
	15	* The kernel maintains two SGLs, the TX SGL and the RX SGL. The TX SGL is
	16	* filled by user space with the data submitted via sendpage/sendmsg. Filling
	17	* up the TX SGL does not cause a crypto operation -- the data will only be
	18	* tracked by the kernel. Upon receipt of one recvmsg call, the caller must
	19	* provide a buffer which is tracked with the RX SGL.
	20	*
	21	* During the processing of the recvmsg operation, the cipher request is
	22	* allocated and prepared. As part of the recvmsg operation, the processed
	23	* TX buffers are extracted from the TX SGL into a separate SGL.
	24	*
	25	* After the completion of the crypto operation, the RX SGL and the cipher
	26	* request is released. The extracted TX SGL parts are released together with
	27	* the RX SGL release.
8ff59090 HX	28	*/
	29
	30	#include <crypto/scatterwalk.h>
	31	#include <crypto/skcipher.h>
	32	#include <crypto/if_alg.h>
	33	#include <linux/init.h>
	34	#include <linux/list.h>
	35	#include <linux/kernel.h>
	36	#include <linux/mm.h>
	37	#include <linux/module.h>
	38	#include <linux/net.h>
	39	#include <net/sock.h>
	40
dd504589 HX	41	struct skcipher_tfm {
	42	struct crypto_skcipher *skcipher;
	43	bool has_key;
	44	};
	45
1b784140 YX	46	static int skcipher_sendmsg(struct socket sock, struct msghdr msg,
1b784140 YX	47	size_t size)
8ff59090 HX	48	{
	49	struct sock *sk = sock->sk;
	50	struct alg_sock *ask = alg_sk(sk);
6454c2b8 HX	51	struct sock *psk = ask->parent;
6454c2b8 HX	52	struct alg_sock *pask = alg_sk(psk);
6454c2b8 HX	53	struct skcipher_tfm *skc = pask->private;
6454c2b8 HX	54	struct crypto_skcipher *tfm = skc->skcipher;
0d96e4ba	55	unsigned ivsize = crypto_skcipher_ivsize(tfm);
8ff59090	56
2d97591e	57	return af_alg_sendmsg(sock, msg, size, ivsize);
a596999b TS	58	}
a596999b TS	59
e870456d SM	60	static int _skcipher_recvmsg(struct socket sock, struct msghdr msg,
e870456d SM	61	size_t ignored, int flags)
a596999b TS	62	{
	63	struct sock *sk = sock->sk;
	64	struct alg_sock *ask = alg_sk(sk);
ec69bbfb HX	65	struct sock *psk = ask->parent;
ec69bbfb HX	66	struct alg_sock *pask = alg_sk(psk);
2d97591e	67	struct af_alg_ctx *ctx = ask->private;
ec69bbfb HX	68	struct skcipher_tfm *skc = pask->private;
ec69bbfb HX	69	struct crypto_skcipher *tfm = skc->skcipher;
e870456d	70	unsigned int bs = crypto_skcipher_blocksize(tfm);
2d97591e	71	struct af_alg_async_req *areq;
e870456d SM	72	int err = 0;
e870456d SM	73	size_t len = 0;
ec69bbfb	74
e870456d	75	/* Allocate cipher request for current operation. */
2d97591e SM	76	areq = af_alg_alloc_areq(sk, sizeof(struct af_alg_async_req) +
	77	crypto_skcipher_reqsize(tfm));
	78	if (IS_ERR(areq))
	79	return PTR_ERR(areq);
a596999b	80
e870456d	81	/* convert iovecs of output buffers into RX SGL */
2d97591e SM	82	err = af_alg_get_rsgl(sk, msg, flags, areq, -1, &len);
	83	if (err)
	84	goto free;
a596999b	85
e870456d SM	86	/* Process only as much RX buffers for which we have TX data */
	87	if (len > ctx->used)
	88	len = ctx->used;
	89
	90	/*
	91	* If more buffers are to be expected to be processed, process only
	92	* full block size buffers.
	93	*/
	94	if (ctx->more \|\| len < ctx->used)
	95	len -= len % bs;
	96
	97	/*
	98	* Create a per request TX SGL for this request which tracks the
	99	* SG entries from the global TX SGL.
	100	*/
2d97591e	101	areq->tsgl_entries = af_alg_count_tsgl(sk, len, 0);
e870456d SM	102	if (!areq->tsgl_entries)
	103	areq->tsgl_entries = 1;
	104	areq->tsgl = sock_kmalloc(sk, sizeof(areq->tsgl) areq->tsgl_entries,
	105	GFP_KERNEL);
	106	if (!areq->tsgl) {
	107	err = -ENOMEM;
	108	goto free;
	109	}
	110	sg_init_table(areq->tsgl, areq->tsgl_entries);
2d97591e	111	af_alg_pull_tsgl(sk, len, areq->tsgl, 0);
e870456d SM	112
e870456d SM	113	/* Initialize the crypto operation */
2d97591e SM	114	skcipher_request_set_tfm(&areq->cra_u.skcipher_req, tfm);
	115	skcipher_request_set_crypt(&areq->cra_u.skcipher_req, areq->tsgl,
	116	areq->first_rsgl.sgl.sg, len, ctx->iv);
e870456d SM	117
	118	if (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) {
	119	/* AIO operation */
7d2c3f54	120	sock_hold(sk);
e870456d	121	areq->iocb = msg->msg_iocb;
2d97591e	122	skcipher_request_set_callback(&areq->cra_u.skcipher_req,
e870456d	123	CRYPTO_TFM_REQ_MAY_SLEEP,
2d97591e SM	124	af_alg_async_cb, areq);
	125	err = ctx->enc ?
	126	crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) :
	127	crypto_skcipher_decrypt(&areq->cra_u.skcipher_req);
7d2c3f54 SM	128
	129	/* AIO operation in progress */
	130	if (err == -EINPROGRESS \|\| err == -EBUSY) {
	131	/* Remember output size that will be generated. */
	132	areq->outlen = len;
	133
	134	return -EIOCBQUEUED;
	135	}
	136
	137	sock_put(sk);
e870456d SM	138	} else {
e870456d SM	139	/* Synchronous operation */
2d97591e	140	skcipher_request_set_callback(&areq->cra_u.skcipher_req,
e870456d SM	141	CRYPTO_TFM_REQ_MAY_SLEEP \|
e870456d SM	142	CRYPTO_TFM_REQ_MAY_BACKLOG,
2c3f8b16 GBY	143	crypto_req_done, &ctx->wait);
2c3f8b16 GBY	144	err = crypto_wait_req(ctx->enc ?
2d97591e SM	145	crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) :
2d97591e SM	146	crypto_skcipher_decrypt(&areq->cra_u.skcipher_req),
2c3f8b16	147	&ctx->wait);
e870456d	148	}
033f46b3	149
e870456d	150
a596999b	151	free:
7d2c3f54	152	af_alg_free_resources(areq);
e870456d SM	153
e870456d SM	154	return err ? err : len;
a596999b TS	155	}
a596999b TS	156
e870456d SM	157	static int skcipher_recvmsg(struct socket sock, struct msghdr msg,
e870456d SM	158	size_t ignored, int flags)
8ff59090 HX	159	{
8ff59090 HX	160	struct sock *sk = sock->sk;
e870456d	161	int ret = 0;
8ff59090 HX	162
8ff59090 HX	163	lock_sock(sk);
01e97e65	164	while (msg_data_left(msg)) {
e870456d SM	165	int err = _skcipher_recvmsg(sock, msg, ignored, flags);
	166
	167	/*
	168	* This error covers -EIOCBQUEUED which implies that we can
	169	* only handle one AIO request. If the caller wants to have
	170	* multiple AIO requests in parallel, he must make multiple
	171	* separate AIO calls.
5703c826 SM	172	*
5703c826 SM	173	* Also return the error if no data has been processed so far.
e870456d SM	174	*/
e870456d SM	175	if (err <= 0) {
5703c826	176	if (err == -EIOCBQUEUED \|\| !ret)
e870456d SM	177	ret = err;
e870456d SM	178	goto out;
1d10eb2f AV	179	}
1d10eb2f AV	180
e870456d	181	ret += err;
8ff59090 HX	182	}
8ff59090 HX	183
e870456d	184	out:
2d97591e	185	af_alg_wmem_wakeup(sk);
8ff59090	186	release_sock(sk);
e870456d	187	return ret;
a596999b	188	}
8ff59090	189
8ff59090 HX	190
	191	static struct proto_ops algif_skcipher_ops = {
	192	.family = PF_ALG,
	193
	194	.connect = sock_no_connect,
	195	.socketpair = sock_no_socketpair,
	196	.getname = sock_no_getname,
	197	.ioctl = sock_no_ioctl,
	198	.listen = sock_no_listen,
	199	.shutdown = sock_no_shutdown,
	200	.getsockopt = sock_no_getsockopt,
	201	.mmap = sock_no_mmap,
	202	.bind = sock_no_bind,
	203	.accept = sock_no_accept,
	204	.setsockopt = sock_no_setsockopt,
	205
	206	.release = af_alg_release,
	207	.sendmsg = skcipher_sendmsg,
2d97591e	208	.sendpage = af_alg_sendpage,
8ff59090	209	.recvmsg = skcipher_recvmsg,
2d97591e	210	.poll = af_alg_poll,
8ff59090 HX	211	};
8ff59090 HX	212
a0fa2d03 HX	213	static int skcipher_check_key(struct socket *sock)
a0fa2d03 HX	214	{
1822793a	215	int err = 0;
a0fa2d03 HX	216	struct sock *psk;
	217	struct alg_sock *pask;
	218	struct skcipher_tfm *tfm;
	219	struct sock *sk = sock->sk;
	220	struct alg_sock *ask = alg_sk(sk);
	221
1822793a	222	lock_sock(sk);
a0fa2d03	223	if (ask->refcnt)
1822793a	224	goto unlock_child;
a0fa2d03 HX	225
	226	psk = ask->parent;
	227	pask = alg_sk(ask->parent);
	228	tfm = pask->private;
	229
	230	err = -ENOKEY;
1822793a	231	lock_sock_nested(psk, SINGLE_DEPTH_NESTING);
a0fa2d03 HX	232	if (!tfm->has_key)
	233	goto unlock;
	234
	235	if (!pask->refcnt++)
	236	sock_hold(psk);
	237
	238	ask->refcnt = 1;
	239	sock_put(psk);
	240
	241	err = 0;
	242
	243	unlock:
	244	release_sock(psk);
1822793a HX	245	unlock_child:
1822793a HX	246	release_sock(sk);
a0fa2d03 HX	247
	248	return err;
	249	}
	250
	251	static int skcipher_sendmsg_nokey(struct socket sock, struct msghdr msg,
	252	size_t size)
	253	{
	254	int err;
	255
	256	err = skcipher_check_key(sock);
	257	if (err)
	258	return err;
	259
	260	return skcipher_sendmsg(sock, msg, size);
	261	}
	262
	263	static ssize_t skcipher_sendpage_nokey(struct socket sock, struct page page,
	264	int offset, size_t size, int flags)
	265	{
	266	int err;
	267
	268	err = skcipher_check_key(sock);
	269	if (err)
	270	return err;
	271
2d97591e	272	return af_alg_sendpage(sock, page, offset, size, flags);
a0fa2d03 HX	273	}
	274
	275	static int skcipher_recvmsg_nokey(struct socket sock, struct msghdr msg,
	276	size_t ignored, int flags)
	277	{
	278	int err;
	279
	280	err = skcipher_check_key(sock);
	281	if (err)
	282	return err;
	283
	284	return skcipher_recvmsg(sock, msg, ignored, flags);
	285	}
	286
	287	static struct proto_ops algif_skcipher_ops_nokey = {
	288	.family = PF_ALG,
	289
	290	.connect = sock_no_connect,
	291	.socketpair = sock_no_socketpair,
	292	.getname = sock_no_getname,
	293	.ioctl = sock_no_ioctl,
	294	.listen = sock_no_listen,
	295	.shutdown = sock_no_shutdown,
	296	.getsockopt = sock_no_getsockopt,
	297	.mmap = sock_no_mmap,
	298	.bind = sock_no_bind,
	299	.accept = sock_no_accept,
	300	.setsockopt = sock_no_setsockopt,
	301
	302	.release = af_alg_release,
	303	.sendmsg = skcipher_sendmsg_nokey,
	304	.sendpage = skcipher_sendpage_nokey,
	305	.recvmsg = skcipher_recvmsg_nokey,
2d97591e	306	.poll = af_alg_poll,
a0fa2d03 HX	307	};
a0fa2d03 HX	308
8ff59090 HX	309	static void skcipher_bind(const char name, u32 type, u32 mask)
8ff59090 HX	310	{
dd504589 HX	311	struct skcipher_tfm *tfm;
	312	struct crypto_skcipher *skcipher;
	313
	314	tfm = kzalloc(sizeof(*tfm), GFP_KERNEL);
	315	if (!tfm)
	316	return ERR_PTR(-ENOMEM);
	317
	318	skcipher = crypto_alloc_skcipher(name, type, mask);
	319	if (IS_ERR(skcipher)) {
	320	kfree(tfm);
	321	return ERR_CAST(skcipher);
	322	}
	323
	324	tfm->skcipher = skcipher;
	325
	326	return tfm;
8ff59090 HX	327	}
	328
	329	static void skcipher_release(void *private)
	330	{
dd504589 HX	331	struct skcipher_tfm *tfm = private;
	332
	333	crypto_free_skcipher(tfm->skcipher);
	334	kfree(tfm);
8ff59090 HX	335	}
	336
	337	static int skcipher_setkey(void private, const u8 key, unsigned int keylen)
	338	{
dd504589 HX	339	struct skcipher_tfm *tfm = private;
	340	int err;
	341
	342	err = crypto_skcipher_setkey(tfm->skcipher, key, keylen);
	343	tfm->has_key = !err;
	344
	345	return err;
8ff59090 HX	346	}
	347
	348	static void skcipher_sock_destruct(struct sock *sk)
	349	{
	350	struct alg_sock *ask = alg_sk(sk);
2d97591e	351	struct af_alg_ctx *ctx = ask->private;
e870456d SM	352	struct sock *psk = ask->parent;
	353	struct alg_sock *pask = alg_sk(psk);
	354	struct skcipher_tfm *skc = pask->private;
	355	struct crypto_skcipher *tfm = skc->skcipher;
a596999b	356
2d97591e	357	af_alg_pull_tsgl(sk, ctx->used, NULL, 0);
0d96e4ba	358	sock_kzfree_s(sk, ctx->iv, crypto_skcipher_ivsize(tfm));
8ff59090 HX	359	sock_kfree_s(sk, ctx, ctx->len);
	360	af_alg_release_parent(sk);
	361	}
	362
d7b65aee	363	static int skcipher_accept_parent_nokey(void private, struct sock sk)
8ff59090	364	{
2d97591e	365	struct af_alg_ctx *ctx;
8ff59090	366	struct alg_sock *ask = alg_sk(sk);
dd504589 HX	367	struct skcipher_tfm *tfm = private;
dd504589 HX	368	struct crypto_skcipher *skcipher = tfm->skcipher;
e870456d	369	unsigned int len = sizeof(*ctx);
8ff59090 HX	370
	371	ctx = sock_kmalloc(sk, len, GFP_KERNEL);
	372	if (!ctx)
	373	return -ENOMEM;
	374
dd504589	375	ctx->iv = sock_kmalloc(sk, crypto_skcipher_ivsize(skcipher),
8ff59090 HX	376	GFP_KERNEL);
	377	if (!ctx->iv) {
	378	sock_kfree_s(sk, ctx, len);
	379	return -ENOMEM;
	380	}
	381
dd504589	382	memset(ctx->iv, 0, crypto_skcipher_ivsize(skcipher));
8ff59090	383
e870456d	384	INIT_LIST_HEAD(&ctx->tsgl_list);
8ff59090 HX	385	ctx->len = len;
8ff59090 HX	386	ctx->used = 0;
e870456d	387	ctx->rcvused = 0;
8ff59090 HX	388	ctx->more = 0;
	389	ctx->merge = 0;
	390	ctx->enc = 0;
2c3f8b16	391	crypto_init_wait(&ctx->wait);
8ff59090 HX	392
	393	ask->private = ctx;
	394
8ff59090 HX	395	sk->sk_destruct = skcipher_sock_destruct;
	396
	397	return 0;
	398	}
	399
a0fa2d03 HX	400	static int skcipher_accept_parent(void private, struct sock sk)
	401	{
	402	struct skcipher_tfm *tfm = private;
	403
6e8d8ecf	404	if (!tfm->has_key && crypto_skcipher_has_setkey(tfm->skcipher))
a0fa2d03 HX	405	return -ENOKEY;
a0fa2d03 HX	406
d7b65aee	407	return skcipher_accept_parent_nokey(private, sk);
a0fa2d03 HX	408	}
a0fa2d03 HX	409
8ff59090 HX	410	static const struct af_alg_type algif_type_skcipher = {
	411	.bind = skcipher_bind,
	412	.release = skcipher_release,
	413	.setkey = skcipher_setkey,
	414	.accept = skcipher_accept_parent,
a0fa2d03	415	.accept_nokey = skcipher_accept_parent_nokey,
8ff59090	416	.ops = &algif_skcipher_ops,
a0fa2d03	417	.ops_nokey = &algif_skcipher_ops_nokey,
8ff59090 HX	418	.name = "skcipher",
	419	.owner = THIS_MODULE
	420	};
	421
	422	static int __init algif_skcipher_init(void)
	423	{
	424	return af_alg_register_type(&algif_type_skcipher);
	425	}
	426
	427	static void __exit algif_skcipher_exit(void)
	428	{
	429	int err = af_alg_unregister_type(&algif_type_skcipher);
	430	BUG_ON(err);
	431	}
	432
	433	module_init(algif_skcipher_init);
	434	module_exit(algif_skcipher_exit);
	435	MODULE_LICENSE("GPL");