[linux-2.6-block.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 */
		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);
	} 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);
	}

	/* AIO operation in progress */
	if (err == -EINPROGRESS) {
		sock_hold(sk);

		/* Remember output size that will be generated. */
		areq->outlen = len;

		return -EIOCBQUEUED;
	}

free:
	af_alg_free_areq_sgls(areq);
	sock_kfree_s(sk, areq, areq->areqlen);

	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 */
	120	areq->iocb = msg->msg_iocb;
2d97591e	121	skcipher_request_set_callback(&areq->cra_u.skcipher_req,
e870456d	122	CRYPTO_TFM_REQ_MAY_SLEEP,
2d97591e SM	123	af_alg_async_cb, areq);
	124	err = ctx->enc ?
	125	crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) :
	126	crypto_skcipher_decrypt(&areq->cra_u.skcipher_req);
e870456d SM	127	} else {
e870456d SM	128	/* Synchronous operation */
2d97591e	129	skcipher_request_set_callback(&areq->cra_u.skcipher_req,
e870456d SM	130	CRYPTO_TFM_REQ_MAY_SLEEP \|
e870456d SM	131	CRYPTO_TFM_REQ_MAY_BACKLOG,
2c3f8b16 GBY	132	crypto_req_done, &ctx->wait);
2c3f8b16 GBY	133	err = crypto_wait_req(ctx->enc ?
2d97591e SM	134	crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) :
2d97591e SM	135	crypto_skcipher_decrypt(&areq->cra_u.skcipher_req),
2c3f8b16	136	&ctx->wait);
e870456d	137	}
033f46b3	138
e870456d	139	/* AIO operation in progress */
a596999b	140	if (err == -EINPROGRESS) {
e870456d	141	sock_hold(sk);
2d97591e SM	142
	143	/* Remember output size that will be generated. */
	144	areq->outlen = len;
	145
e870456d	146	return -EIOCBQUEUED;
a596999b	147	}
e870456d	148
a596999b	149	free:
2d97591e SM	150	af_alg_free_areq_sgls(areq);
2d97591e SM	151	sock_kfree_s(sk, areq, areq->areqlen);
e870456d SM	152
e870456d SM	153	return err ? err : len;
a596999b TS	154	}
a596999b TS	155
e870456d SM	156	static int skcipher_recvmsg(struct socket sock, struct msghdr msg,
e870456d SM	157	size_t ignored, int flags)
8ff59090 HX	158	{
8ff59090 HX	159	struct sock *sk = sock->sk;
e870456d	160	int ret = 0;
8ff59090 HX	161
8ff59090 HX	162	lock_sock(sk);
01e97e65	163	while (msg_data_left(msg)) {
e870456d SM	164	int err = _skcipher_recvmsg(sock, msg, ignored, flags);
	165
	166	/*
	167	* This error covers -EIOCBQUEUED which implies that we can
	168	* only handle one AIO request. If the caller wants to have
	169	* multiple AIO requests in parallel, he must make multiple
	170	* separate AIO calls.
5703c826 SM	171	*
5703c826 SM	172	* Also return the error if no data has been processed so far.
e870456d SM	173	*/
e870456d SM	174	if (err <= 0) {
5703c826	175	if (err == -EIOCBQUEUED \|\| !ret)
e870456d SM	176	ret = err;
e870456d SM	177	goto out;
1d10eb2f AV	178	}
1d10eb2f AV	179
e870456d	180	ret += err;
8ff59090 HX	181	}
8ff59090 HX	182
e870456d	183	out:
2d97591e	184	af_alg_wmem_wakeup(sk);
8ff59090	185	release_sock(sk);
e870456d	186	return ret;
a596999b	187	}
8ff59090	188
8ff59090 HX	189
	190	static struct proto_ops algif_skcipher_ops = {
	191	.family = PF_ALG,
	192
	193	.connect = sock_no_connect,
	194	.socketpair = sock_no_socketpair,
	195	.getname = sock_no_getname,
	196	.ioctl = sock_no_ioctl,
	197	.listen = sock_no_listen,
	198	.shutdown = sock_no_shutdown,
	199	.getsockopt = sock_no_getsockopt,
	200	.mmap = sock_no_mmap,
	201	.bind = sock_no_bind,
	202	.accept = sock_no_accept,
	203	.setsockopt = sock_no_setsockopt,
	204
	205	.release = af_alg_release,
	206	.sendmsg = skcipher_sendmsg,
2d97591e	207	.sendpage = af_alg_sendpage,
8ff59090	208	.recvmsg = skcipher_recvmsg,
2d97591e	209	.poll = af_alg_poll,
8ff59090 HX	210	};
8ff59090 HX	211
a0fa2d03 HX	212	static int skcipher_check_key(struct socket *sock)
a0fa2d03 HX	213	{
1822793a	214	int err = 0;
a0fa2d03 HX	215	struct sock *psk;
	216	struct alg_sock *pask;
	217	struct skcipher_tfm *tfm;
	218	struct sock *sk = sock->sk;
	219	struct alg_sock *ask = alg_sk(sk);
	220
1822793a	221	lock_sock(sk);
a0fa2d03	222	if (ask->refcnt)
1822793a	223	goto unlock_child;
a0fa2d03 HX	224
	225	psk = ask->parent;
	226	pask = alg_sk(ask->parent);
	227	tfm = pask->private;
	228
	229	err = -ENOKEY;
1822793a	230	lock_sock_nested(psk, SINGLE_DEPTH_NESTING);
a0fa2d03 HX	231	if (!tfm->has_key)
	232	goto unlock;
	233
	234	if (!pask->refcnt++)
	235	sock_hold(psk);
	236
	237	ask->refcnt = 1;
	238	sock_put(psk);
	239
	240	err = 0;
	241
	242	unlock:
	243	release_sock(psk);
1822793a HX	244	unlock_child:
1822793a HX	245	release_sock(sk);
a0fa2d03 HX	246
	247	return err;
	248	}
	249
	250	static int skcipher_sendmsg_nokey(struct socket sock, struct msghdr msg,
	251	size_t size)
	252	{
	253	int err;
	254
	255	err = skcipher_check_key(sock);
	256	if (err)
	257	return err;
	258
	259	return skcipher_sendmsg(sock, msg, size);
	260	}
	261
	262	static ssize_t skcipher_sendpage_nokey(struct socket sock, struct page page,
	263	int offset, size_t size, int flags)
	264	{
	265	int err;
	266
	267	err = skcipher_check_key(sock);
	268	if (err)
	269	return err;
	270
2d97591e	271	return af_alg_sendpage(sock, page, offset, size, flags);
a0fa2d03 HX	272	}
	273
	274	static int skcipher_recvmsg_nokey(struct socket sock, struct msghdr msg,
	275	size_t ignored, int flags)
	276	{
	277	int err;
	278
	279	err = skcipher_check_key(sock);
	280	if (err)
	281	return err;
	282
	283	return skcipher_recvmsg(sock, msg, ignored, flags);
	284	}
	285
	286	static struct proto_ops algif_skcipher_ops_nokey = {
	287	.family = PF_ALG,
	288
	289	.connect = sock_no_connect,
	290	.socketpair = sock_no_socketpair,
	291	.getname = sock_no_getname,
	292	.ioctl = sock_no_ioctl,
	293	.listen = sock_no_listen,
	294	.shutdown = sock_no_shutdown,
	295	.getsockopt = sock_no_getsockopt,
	296	.mmap = sock_no_mmap,
	297	.bind = sock_no_bind,
	298	.accept = sock_no_accept,
	299	.setsockopt = sock_no_setsockopt,
	300
	301	.release = af_alg_release,
	302	.sendmsg = skcipher_sendmsg_nokey,
	303	.sendpage = skcipher_sendpage_nokey,
	304	.recvmsg = skcipher_recvmsg_nokey,
2d97591e	305	.poll = af_alg_poll,
a0fa2d03 HX	306	};
a0fa2d03 HX	307
8ff59090 HX	308	static void skcipher_bind(const char name, u32 type, u32 mask)
8ff59090 HX	309	{
dd504589 HX	310	struct skcipher_tfm *tfm;
	311	struct crypto_skcipher *skcipher;
	312
	313	tfm = kzalloc(sizeof(*tfm), GFP_KERNEL);
	314	if (!tfm)
	315	return ERR_PTR(-ENOMEM);
	316
	317	skcipher = crypto_alloc_skcipher(name, type, mask);
	318	if (IS_ERR(skcipher)) {
	319	kfree(tfm);
	320	return ERR_CAST(skcipher);
	321	}
	322
	323	tfm->skcipher = skcipher;
	324
	325	return tfm;
8ff59090 HX	326	}
	327
	328	static void skcipher_release(void *private)
	329	{
dd504589 HX	330	struct skcipher_tfm *tfm = private;
	331
	332	crypto_free_skcipher(tfm->skcipher);
	333	kfree(tfm);
8ff59090 HX	334	}
	335
	336	static int skcipher_setkey(void private, const u8 key, unsigned int keylen)
	337	{
dd504589 HX	338	struct skcipher_tfm *tfm = private;
	339	int err;
	340
	341	err = crypto_skcipher_setkey(tfm->skcipher, key, keylen);
	342	tfm->has_key = !err;
	343
	344	return err;
8ff59090 HX	345	}
	346
	347	static void skcipher_sock_destruct(struct sock *sk)
	348	{
	349	struct alg_sock *ask = alg_sk(sk);
2d97591e	350	struct af_alg_ctx *ctx = ask->private;
e870456d SM	351	struct sock *psk = ask->parent;
	352	struct alg_sock *pask = alg_sk(psk);
	353	struct skcipher_tfm *skc = pask->private;
	354	struct crypto_skcipher *tfm = skc->skcipher;
a596999b	355
2d97591e	356	af_alg_pull_tsgl(sk, ctx->used, NULL, 0);
0d96e4ba	357	sock_kzfree_s(sk, ctx->iv, crypto_skcipher_ivsize(tfm));
8ff59090 HX	358	sock_kfree_s(sk, ctx, ctx->len);
	359	af_alg_release_parent(sk);
	360	}
	361
d7b65aee	362	static int skcipher_accept_parent_nokey(void private, struct sock sk)
8ff59090	363	{
2d97591e	364	struct af_alg_ctx *ctx;
8ff59090	365	struct alg_sock *ask = alg_sk(sk);
dd504589 HX	366	struct skcipher_tfm *tfm = private;
dd504589 HX	367	struct crypto_skcipher *skcipher = tfm->skcipher;
e870456d	368	unsigned int len = sizeof(*ctx);
8ff59090 HX	369
	370	ctx = sock_kmalloc(sk, len, GFP_KERNEL);
	371	if (!ctx)
	372	return -ENOMEM;
	373
dd504589	374	ctx->iv = sock_kmalloc(sk, crypto_skcipher_ivsize(skcipher),
8ff59090 HX	375	GFP_KERNEL);
	376	if (!ctx->iv) {
	377	sock_kfree_s(sk, ctx, len);
	378	return -ENOMEM;
	379	}
	380
dd504589	381	memset(ctx->iv, 0, crypto_skcipher_ivsize(skcipher));
8ff59090	382
e870456d	383	INIT_LIST_HEAD(&ctx->tsgl_list);
8ff59090 HX	384	ctx->len = len;
8ff59090 HX	385	ctx->used = 0;
e870456d	386	ctx->rcvused = 0;
8ff59090 HX	387	ctx->more = 0;
	388	ctx->merge = 0;
	389	ctx->enc = 0;
2c3f8b16	390	crypto_init_wait(&ctx->wait);
8ff59090 HX	391
	392	ask->private = ctx;
	393
8ff59090 HX	394	sk->sk_destruct = skcipher_sock_destruct;
	395
	396	return 0;
	397	}
	398
a0fa2d03 HX	399	static int skcipher_accept_parent(void private, struct sock sk)
	400	{
	401	struct skcipher_tfm *tfm = private;
	402
6e8d8ecf	403	if (!tfm->has_key && crypto_skcipher_has_setkey(tfm->skcipher))
a0fa2d03 HX	404	return -ENOKEY;
a0fa2d03 HX	405
d7b65aee	406	return skcipher_accept_parent_nokey(private, sk);
a0fa2d03 HX	407	}
a0fa2d03 HX	408
8ff59090 HX	409	static const struct af_alg_type algif_type_skcipher = {
	410	.bind = skcipher_bind,
	411	.release = skcipher_release,
	412	.setkey = skcipher_setkey,
	413	.accept = skcipher_accept_parent,
a0fa2d03	414	.accept_nokey = skcipher_accept_parent_nokey,
8ff59090	415	.ops = &algif_skcipher_ops,
a0fa2d03	416	.ops_nokey = &algif_skcipher_ops_nokey,
8ff59090 HX	417	.name = "skcipher",
	418	.owner = THIS_MODULE
	419	};
	420
	421	static int __init algif_skcipher_init(void)
	422	{
	423	return af_alg_register_type(&algif_type_skcipher);
	424	}
	425
	426	static void __exit algif_skcipher_exit(void)
	427	{
	428	int err = af_alg_unregister_type(&algif_type_skcipher);
	429	BUG_ON(err);
	430	}
	431
	432	module_init(algif_skcipher_init);
	433	module_exit(algif_skcipher_exit);
	434	MODULE_LICENSE("GPL");