[GitHub/LineageOS/android_kernel_motorola_exynos9610.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;

	if (!ctx->used) {
		err = af_alg_wait_for_data(sk, flags);
		if (err)
			return err;
	}

	/* 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;

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

		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)
			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,
					      af_alg_complete,
					      &ctx->completion);
		err = af_alg_wait_for_completion(ctx->enc ?
			crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) :
			crypto_skcipher_decrypt(&areq->cra_u.skcipher_req),
						 &ctx->completion);
	}


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;
	atomic_set(&ctx->rcvused, 0);
	ctx->more = 0;
	ctx->merge = 0;
	ctx->enc = 0;
	af_alg_init_completion(&ctx->completion);

	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
c692698e SM	75	if (!ctx->used) {
	76	err = af_alg_wait_for_data(sk, flags);
	77	if (err)
	78	return err;
	79	}
	80
e870456d	81	/* Allocate cipher request for current operation. */
2d97591e SM	82	areq = af_alg_alloc_areq(sk, sizeof(struct af_alg_async_req) +
	83	crypto_skcipher_reqsize(tfm));
	84	if (IS_ERR(areq))
	85	return PTR_ERR(areq);
a596999b	86
e870456d	87	/* convert iovecs of output buffers into RX SGL */
2d97591e SM	88	err = af_alg_get_rsgl(sk, msg, flags, areq, -1, &len);
	89	if (err)
	90	goto free;
a596999b	91
e870456d SM	92	/* Process only as much RX buffers for which we have TX data */
	93	if (len > ctx->used)
	94	len = ctx->used;
	95
	96	/*
	97	* If more buffers are to be expected to be processed, process only
	98	* full block size buffers.
	99	*/
	100	if (ctx->more \|\| len < ctx->used)
	101	len -= len % bs;
	102
	103	/*
	104	* Create a per request TX SGL for this request which tracks the
	105	* SG entries from the global TX SGL.
	106	*/
2d97591e	107	areq->tsgl_entries = af_alg_count_tsgl(sk, len, 0);
e870456d SM	108	if (!areq->tsgl_entries)
	109	areq->tsgl_entries = 1;
	110	areq->tsgl = sock_kmalloc(sk, sizeof(areq->tsgl) areq->tsgl_entries,
	111	GFP_KERNEL);
	112	if (!areq->tsgl) {
	113	err = -ENOMEM;
	114	goto free;
	115	}
	116	sg_init_table(areq->tsgl, areq->tsgl_entries);
2d97591e	117	af_alg_pull_tsgl(sk, len, areq->tsgl, 0);
e870456d SM	118
e870456d SM	119	/* Initialize the crypto operation */
2d97591e SM	120	skcipher_request_set_tfm(&areq->cra_u.skcipher_req, tfm);
	121	skcipher_request_set_crypt(&areq->cra_u.skcipher_req, areq->tsgl,
	122	areq->first_rsgl.sgl.sg, len, ctx->iv);
e870456d SM	123
	124	if (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) {
	125	/* AIO operation */
7f21961a	126	sock_hold(sk);
e870456d	127	areq->iocb = msg->msg_iocb;
f09fca41 SM	128
	129	/* Remember output size that will be generated. */
	130	areq->outlen = len;
	131
2d97591e	132	skcipher_request_set_callback(&areq->cra_u.skcipher_req,
e870456d	133	CRYPTO_TFM_REQ_MAY_SLEEP,
2d97591e SM	134	af_alg_async_cb, areq);
	135	err = ctx->enc ?
	136	crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) :
	137	crypto_skcipher_decrypt(&areq->cra_u.skcipher_req);
7f21961a SM	138
7f21961a SM	139	/* AIO operation in progress */
f09fca41	140	if (err == -EINPROGRESS \|\| err == -EBUSY)
7f21961a	141	return -EIOCBQUEUED;
7f21961a SM	142
7f21961a SM	143	sock_put(sk);
e870456d SM	144	} else {
e870456d SM	145	/* Synchronous operation */
2d97591e	146	skcipher_request_set_callback(&areq->cra_u.skcipher_req,
e870456d SM	147	CRYPTO_TFM_REQ_MAY_SLEEP \|
	148	CRYPTO_TFM_REQ_MAY_BACKLOG,
	149	af_alg_complete,
	150	&ctx->completion);
	151	err = af_alg_wait_for_completion(ctx->enc ?
2d97591e SM	152	crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) :
2d97591e SM	153	crypto_skcipher_decrypt(&areq->cra_u.skcipher_req),
e870456d SM	154	&ctx->completion);
e870456d SM	155	}
033f46b3	156
e870456d	157
a596999b	158	free:
7f21961a	159	af_alg_free_resources(areq);
e870456d SM	160
e870456d SM	161	return err ? err : len;
a596999b TS	162	}
a596999b TS	163
e870456d SM	164	static int skcipher_recvmsg(struct socket sock, struct msghdr msg,
e870456d SM	165	size_t ignored, int flags)
8ff59090 HX	166	{
8ff59090 HX	167	struct sock *sk = sock->sk;
e870456d	168	int ret = 0;
8ff59090 HX	169
8ff59090 HX	170	lock_sock(sk);
01e97e65	171	while (msg_data_left(msg)) {
e870456d SM	172	int err = _skcipher_recvmsg(sock, msg, ignored, flags);
	173
	174	/*
	175	* This error covers -EIOCBQUEUED which implies that we can
	176	* only handle one AIO request. If the caller wants to have
	177	* multiple AIO requests in parallel, he must make multiple
	178	* separate AIO calls.
5703c826 SM	179	*
5703c826 SM	180	* Also return the error if no data has been processed so far.
e870456d SM	181	*/
e870456d SM	182	if (err <= 0) {
5703c826	183	if (err == -EIOCBQUEUED \|\| !ret)
e870456d SM	184	ret = err;
e870456d SM	185	goto out;
1d10eb2f AV	186	}
1d10eb2f AV	187
e870456d	188	ret += err;
8ff59090 HX	189	}
8ff59090 HX	190
e870456d	191	out:
2d97591e	192	af_alg_wmem_wakeup(sk);
8ff59090	193	release_sock(sk);
e870456d	194	return ret;
a596999b	195	}
8ff59090	196
8ff59090 HX	197
	198	static struct proto_ops algif_skcipher_ops = {
	199	.family = PF_ALG,
	200
	201	.connect = sock_no_connect,
	202	.socketpair = sock_no_socketpair,
	203	.getname = sock_no_getname,
	204	.ioctl = sock_no_ioctl,
	205	.listen = sock_no_listen,
	206	.shutdown = sock_no_shutdown,
	207	.getsockopt = sock_no_getsockopt,
	208	.mmap = sock_no_mmap,
	209	.bind = sock_no_bind,
	210	.accept = sock_no_accept,
	211	.setsockopt = sock_no_setsockopt,
	212
	213	.release = af_alg_release,
	214	.sendmsg = skcipher_sendmsg,
2d97591e	215	.sendpage = af_alg_sendpage,
8ff59090	216	.recvmsg = skcipher_recvmsg,
2d97591e	217	.poll = af_alg_poll,
8ff59090 HX	218	};
8ff59090 HX	219
a0fa2d03 HX	220	static int skcipher_check_key(struct socket *sock)
a0fa2d03 HX	221	{
1822793a	222	int err = 0;
a0fa2d03 HX	223	struct sock *psk;
	224	struct alg_sock *pask;
	225	struct skcipher_tfm *tfm;
	226	struct sock *sk = sock->sk;
	227	struct alg_sock *ask = alg_sk(sk);
	228
1822793a	229	lock_sock(sk);
a0fa2d03	230	if (ask->refcnt)
1822793a	231	goto unlock_child;
a0fa2d03 HX	232
	233	psk = ask->parent;
	234	pask = alg_sk(ask->parent);
	235	tfm = pask->private;
	236
	237	err = -ENOKEY;
1822793a	238	lock_sock_nested(psk, SINGLE_DEPTH_NESTING);
a0fa2d03 HX	239	if (!tfm->has_key)
	240	goto unlock;
	241
	242	if (!pask->refcnt++)
	243	sock_hold(psk);
	244
	245	ask->refcnt = 1;
	246	sock_put(psk);
	247
	248	err = 0;
	249
	250	unlock:
	251	release_sock(psk);
1822793a HX	252	unlock_child:
1822793a HX	253	release_sock(sk);
a0fa2d03 HX	254
	255	return err;
	256	}
	257
	258	static int skcipher_sendmsg_nokey(struct socket sock, struct msghdr msg,
	259	size_t size)
	260	{
	261	int err;
	262
	263	err = skcipher_check_key(sock);
	264	if (err)
	265	return err;
	266
	267	return skcipher_sendmsg(sock, msg, size);
	268	}
	269
	270	static ssize_t skcipher_sendpage_nokey(struct socket sock, struct page page,
	271	int offset, size_t size, int flags)
	272	{
	273	int err;
	274
	275	err = skcipher_check_key(sock);
	276	if (err)
	277	return err;
	278
2d97591e	279	return af_alg_sendpage(sock, page, offset, size, flags);
a0fa2d03 HX	280	}
	281
	282	static int skcipher_recvmsg_nokey(struct socket sock, struct msghdr msg,
	283	size_t ignored, int flags)
	284	{
	285	int err;
	286
	287	err = skcipher_check_key(sock);
	288	if (err)
	289	return err;
	290
	291	return skcipher_recvmsg(sock, msg, ignored, flags);
	292	}
	293
	294	static struct proto_ops algif_skcipher_ops_nokey = {
	295	.family = PF_ALG,
	296
	297	.connect = sock_no_connect,
	298	.socketpair = sock_no_socketpair,
	299	.getname = sock_no_getname,
	300	.ioctl = sock_no_ioctl,
	301	.listen = sock_no_listen,
	302	.shutdown = sock_no_shutdown,
	303	.getsockopt = sock_no_getsockopt,
	304	.mmap = sock_no_mmap,
	305	.bind = sock_no_bind,
	306	.accept = sock_no_accept,
	307	.setsockopt = sock_no_setsockopt,
	308
	309	.release = af_alg_release,
	310	.sendmsg = skcipher_sendmsg_nokey,
	311	.sendpage = skcipher_sendpage_nokey,
	312	.recvmsg = skcipher_recvmsg_nokey,
2d97591e	313	.poll = af_alg_poll,
a0fa2d03 HX	314	};
a0fa2d03 HX	315
8ff59090 HX	316	static void skcipher_bind(const char name, u32 type, u32 mask)
8ff59090 HX	317	{
dd504589 HX	318	struct skcipher_tfm *tfm;
	319	struct crypto_skcipher *skcipher;
	320
	321	tfm = kzalloc(sizeof(*tfm), GFP_KERNEL);
	322	if (!tfm)
	323	return ERR_PTR(-ENOMEM);
	324
	325	skcipher = crypto_alloc_skcipher(name, type, mask);
	326	if (IS_ERR(skcipher)) {
	327	kfree(tfm);
	328	return ERR_CAST(skcipher);
	329	}
	330
	331	tfm->skcipher = skcipher;
	332
	333	return tfm;
8ff59090 HX	334	}
	335
	336	static void skcipher_release(void *private)
	337	{
dd504589 HX	338	struct skcipher_tfm *tfm = private;
	339
	340	crypto_free_skcipher(tfm->skcipher);
	341	kfree(tfm);
8ff59090 HX	342	}
	343
	344	static int skcipher_setkey(void private, const u8 key, unsigned int keylen)
	345	{
dd504589 HX	346	struct skcipher_tfm *tfm = private;
	347	int err;
	348
	349	err = crypto_skcipher_setkey(tfm->skcipher, key, keylen);
	350	tfm->has_key = !err;
	351
	352	return err;
8ff59090 HX	353	}
	354
	355	static void skcipher_sock_destruct(struct sock *sk)
	356	{
	357	struct alg_sock *ask = alg_sk(sk);
2d97591e	358	struct af_alg_ctx *ctx = ask->private;
e870456d SM	359	struct sock *psk = ask->parent;
	360	struct alg_sock *pask = alg_sk(psk);
	361	struct skcipher_tfm *skc = pask->private;
	362	struct crypto_skcipher *tfm = skc->skcipher;
a596999b	363
2d97591e	364	af_alg_pull_tsgl(sk, ctx->used, NULL, 0);
0d96e4ba	365	sock_kzfree_s(sk, ctx->iv, crypto_skcipher_ivsize(tfm));
8ff59090 HX	366	sock_kfree_s(sk, ctx, ctx->len);
	367	af_alg_release_parent(sk);
	368	}
	369
d7b65aee	370	static int skcipher_accept_parent_nokey(void private, struct sock sk)
8ff59090	371	{
2d97591e	372	struct af_alg_ctx *ctx;
8ff59090	373	struct alg_sock *ask = alg_sk(sk);
dd504589 HX	374	struct skcipher_tfm *tfm = private;
dd504589 HX	375	struct crypto_skcipher *skcipher = tfm->skcipher;
e870456d	376	unsigned int len = sizeof(*ctx);
8ff59090 HX	377
	378	ctx = sock_kmalloc(sk, len, GFP_KERNEL);
	379	if (!ctx)
	380	return -ENOMEM;
	381
dd504589	382	ctx->iv = sock_kmalloc(sk, crypto_skcipher_ivsize(skcipher),
8ff59090 HX	383	GFP_KERNEL);
	384	if (!ctx->iv) {
	385	sock_kfree_s(sk, ctx, len);
	386	return -ENOMEM;
	387	}
	388
dd504589	389	memset(ctx->iv, 0, crypto_skcipher_ivsize(skcipher));
8ff59090	390
e870456d	391	INIT_LIST_HEAD(&ctx->tsgl_list);
8ff59090 HX	392	ctx->len = len;
8ff59090 HX	393	ctx->used = 0;
36d0a678	394	atomic_set(&ctx->rcvused, 0);
8ff59090 HX	395	ctx->more = 0;
	396	ctx->merge = 0;
	397	ctx->enc = 0;
	398	af_alg_init_completion(&ctx->completion);
	399
	400	ask->private = ctx;
	401
8ff59090 HX	402	sk->sk_destruct = skcipher_sock_destruct;
	403
	404	return 0;
	405	}
	406
a0fa2d03 HX	407	static int skcipher_accept_parent(void private, struct sock sk)
	408	{
	409	struct skcipher_tfm *tfm = private;
	410
6e8d8ecf	411	if (!tfm->has_key && crypto_skcipher_has_setkey(tfm->skcipher))
a0fa2d03 HX	412	return -ENOKEY;
a0fa2d03 HX	413
d7b65aee	414	return skcipher_accept_parent_nokey(private, sk);
a0fa2d03 HX	415	}
a0fa2d03 HX	416
8ff59090 HX	417	static const struct af_alg_type algif_type_skcipher = {
	418	.bind = skcipher_bind,
	419	.release = skcipher_release,
	420	.setkey = skcipher_setkey,
	421	.accept = skcipher_accept_parent,
a0fa2d03	422	.accept_nokey = skcipher_accept_parent_nokey,
8ff59090	423	.ops = &algif_skcipher_ops,
a0fa2d03	424	.ops_nokey = &algif_skcipher_ops_nokey,
8ff59090 HX	425	.name = "skcipher",
	426	.owner = THIS_MODULE
	427	};
	428
	429	static int __init algif_skcipher_init(void)
	430	{
	431	return af_alg_register_type(&algif_type_skcipher);
	432	}
	433
	434	static void __exit algif_skcipher_exit(void)
	435	{
	436	int err = af_alg_unregister_type(&algif_type_skcipher);
	437	BUG_ON(err);
	438	}
	439
	440	module_init(algif_skcipher_init);
	441	module_exit(algif_skcipher_exit);
	442	MODULE_LICENSE("GPL");