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v5.9
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * algif_skcipher: User-space interface for skcipher algorithms
  4 *
  5 * This file provides the user-space API for symmetric key ciphers.
  6 *
  7 * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
  8 *
  9 * The following concept of the memory management is used:
 10 *
 11 * The kernel maintains two SGLs, the TX SGL and the RX SGL. The TX SGL is
 12 * filled by user space with the data submitted via sendpage/sendmsg. Filling
 13 * up the TX SGL does not cause a crypto operation -- the data will only be
 14 * tracked by the kernel. Upon receipt of one recvmsg call, the caller must
 15 * provide a buffer which is tracked with the RX SGL.
 16 *
 17 * During the processing of the recvmsg operation, the cipher request is
 18 * allocated and prepared. As part of the recvmsg operation, the processed
 19 * TX buffers are extracted from the TX SGL into a separate SGL.
 20 *
 21 * After the completion of the crypto operation, the RX SGL and the cipher
 22 * request is released. The extracted TX SGL parts are released together with
 23 * the RX SGL release.
 24 */
 25
 26#include <crypto/scatterwalk.h>
 27#include <crypto/skcipher.h>
 28#include <crypto/if_alg.h>
 29#include <linux/init.h>
 30#include <linux/list.h>
 31#include <linux/kernel.h>
 32#include <linux/mm.h>
 33#include <linux/module.h>
 34#include <linux/net.h>
 35#include <net/sock.h>
 36
 37static int skcipher_sendmsg(struct socket *sock, struct msghdr *msg,
 38			    size_t size)
 39{
 40	struct sock *sk = sock->sk;
 41	struct alg_sock *ask = alg_sk(sk);
 42	struct sock *psk = ask->parent;
 43	struct alg_sock *pask = alg_sk(psk);
 44	struct crypto_skcipher *tfm = pask->private;
 45	unsigned ivsize = crypto_skcipher_ivsize(tfm);
 46
 47	return af_alg_sendmsg(sock, msg, size, ivsize);
 48}
 49
 50static int _skcipher_recvmsg(struct socket *sock, struct msghdr *msg,
 51			     size_t ignored, int flags)
 52{
 53	struct sock *sk = sock->sk;
 54	struct alg_sock *ask = alg_sk(sk);
 55	struct sock *psk = ask->parent;
 56	struct alg_sock *pask = alg_sk(psk);
 57	struct af_alg_ctx *ctx = ask->private;
 58	struct crypto_skcipher *tfm = pask->private;
 59	unsigned int bs = crypto_skcipher_chunksize(tfm);
 60	struct af_alg_async_req *areq;
 61	int err = 0;
 62	size_t len = 0;
 63
 64	if (!ctx->init || (ctx->more && ctx->used < bs)) {
 65		err = af_alg_wait_for_data(sk, flags, bs);
 66		if (err)
 67			return err;
 68	}
 69
 70	/* Allocate cipher request for current operation. */
 71	areq = af_alg_alloc_areq(sk, sizeof(struct af_alg_async_req) +
 72				     crypto_skcipher_reqsize(tfm));
 73	if (IS_ERR(areq))
 74		return PTR_ERR(areq);
 75
 76	/* convert iovecs of output buffers into RX SGL */
 77	err = af_alg_get_rsgl(sk, msg, flags, areq, ctx->used, &len);
 78	if (err)
 79		goto free;
 80
 81	/*
 82	 * If more buffers are to be expected to be processed, process only
 83	 * full block size buffers.
 84	 */
 85	if (ctx->more || len < ctx->used)
 86		len -= len % bs;
 87
 88	/*
 89	 * Create a per request TX SGL for this request which tracks the
 90	 * SG entries from the global TX SGL.
 91	 */
 92	areq->tsgl_entries = af_alg_count_tsgl(sk, len, 0);
 93	if (!areq->tsgl_entries)
 94		areq->tsgl_entries = 1;
 95	areq->tsgl = sock_kmalloc(sk, array_size(sizeof(*areq->tsgl),
 96						 areq->tsgl_entries),
 97				  GFP_KERNEL);
 98	if (!areq->tsgl) {
 99		err = -ENOMEM;
100		goto free;
101	}
102	sg_init_table(areq->tsgl, areq->tsgl_entries);
103	af_alg_pull_tsgl(sk, len, areq->tsgl, 0);
104
105	/* Initialize the crypto operation */
106	skcipher_request_set_tfm(&areq->cra_u.skcipher_req, tfm);
107	skcipher_request_set_crypt(&areq->cra_u.skcipher_req, areq->tsgl,
108				   areq->first_rsgl.sgl.sg, len, ctx->iv);
109
110	if (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) {
111		/* AIO operation */
112		sock_hold(sk);
113		areq->iocb = msg->msg_iocb;
114
115		/* Remember output size that will be generated. */
116		areq->outlen = len;
117
118		skcipher_request_set_callback(&areq->cra_u.skcipher_req,
119					      CRYPTO_TFM_REQ_MAY_SLEEP,
120					      af_alg_async_cb, areq);
121		err = ctx->enc ?
122			crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) :
123			crypto_skcipher_decrypt(&areq->cra_u.skcipher_req);
124
125		/* AIO operation in progress */
126		if (err == -EINPROGRESS || err == -EBUSY)
127			return -EIOCBQUEUED;
128
129		sock_put(sk);
130	} else {
131		/* Synchronous operation */
132		skcipher_request_set_callback(&areq->cra_u.skcipher_req,
133					      CRYPTO_TFM_REQ_MAY_SLEEP |
134					      CRYPTO_TFM_REQ_MAY_BACKLOG,
135					      crypto_req_done, &ctx->wait);
136		err = crypto_wait_req(ctx->enc ?
137			crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) :
138			crypto_skcipher_decrypt(&areq->cra_u.skcipher_req),
139						 &ctx->wait);
140	}
141
142
143free:
144	af_alg_free_resources(areq);
145
146	return err ? err : len;
147}
148
149static int skcipher_recvmsg(struct socket *sock, struct msghdr *msg,
150			    size_t ignored, int flags)
151{
152	struct sock *sk = sock->sk;
153	int ret = 0;
154
155	lock_sock(sk);
156	while (msg_data_left(msg)) {
157		int err = _skcipher_recvmsg(sock, msg, ignored, flags);
158
159		/*
160		 * This error covers -EIOCBQUEUED which implies that we can
161		 * only handle one AIO request. If the caller wants to have
162		 * multiple AIO requests in parallel, he must make multiple
163		 * separate AIO calls.
164		 *
165		 * Also return the error if no data has been processed so far.
166		 */
167		if (err <= 0) {
168			if (err == -EIOCBQUEUED || !ret)
169				ret = err;
170			goto out;
171		}
172
173		ret += err;
174	}
175
176out:
177	af_alg_wmem_wakeup(sk);
178	release_sock(sk);
179	return ret;
180}
181
182static struct proto_ops algif_skcipher_ops = {
183	.family		=	PF_ALG,
184
185	.connect	=	sock_no_connect,
186	.socketpair	=	sock_no_socketpair,
187	.getname	=	sock_no_getname,
188	.ioctl		=	sock_no_ioctl,
189	.listen		=	sock_no_listen,
190	.shutdown	=	sock_no_shutdown,
191	.mmap		=	sock_no_mmap,
192	.bind		=	sock_no_bind,
193	.accept		=	sock_no_accept,
194
195	.release	=	af_alg_release,
196	.sendmsg	=	skcipher_sendmsg,
197	.sendpage	=	af_alg_sendpage,
198	.recvmsg	=	skcipher_recvmsg,
199	.poll		=	af_alg_poll,
200};
201
202static int skcipher_check_key(struct socket *sock)
203{
204	int err = 0;
205	struct sock *psk;
206	struct alg_sock *pask;
207	struct crypto_skcipher *tfm;
208	struct sock *sk = sock->sk;
209	struct alg_sock *ask = alg_sk(sk);
210
211	lock_sock(sk);
212	if (!atomic_read(&ask->nokey_refcnt))
213		goto unlock_child;
214
215	psk = ask->parent;
216	pask = alg_sk(ask->parent);
217	tfm = pask->private;
218
219	err = -ENOKEY;
220	lock_sock_nested(psk, SINGLE_DEPTH_NESTING);
221	if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
222		goto unlock;
223
224	atomic_dec(&pask->nokey_refcnt);
225	atomic_set(&ask->nokey_refcnt, 0);
226
227	err = 0;
228
229unlock:
230	release_sock(psk);
231unlock_child:
232	release_sock(sk);
233
234	return err;
235}
236
237static int skcipher_sendmsg_nokey(struct socket *sock, struct msghdr *msg,
238				  size_t size)
239{
240	int err;
241
242	err = skcipher_check_key(sock);
243	if (err)
244		return err;
245
246	return skcipher_sendmsg(sock, msg, size);
247}
248
249static ssize_t skcipher_sendpage_nokey(struct socket *sock, struct page *page,
250				       int offset, size_t size, int flags)
251{
252	int err;
253
254	err = skcipher_check_key(sock);
255	if (err)
256		return err;
257
258	return af_alg_sendpage(sock, page, offset, size, flags);
259}
260
261static int skcipher_recvmsg_nokey(struct socket *sock, struct msghdr *msg,
262				  size_t ignored, int flags)
263{
264	int err;
265
266	err = skcipher_check_key(sock);
267	if (err)
268		return err;
269
270	return skcipher_recvmsg(sock, msg, ignored, flags);
271}
272
273static struct proto_ops algif_skcipher_ops_nokey = {
274	.family		=	PF_ALG,
275
276	.connect	=	sock_no_connect,
277	.socketpair	=	sock_no_socketpair,
278	.getname	=	sock_no_getname,
279	.ioctl		=	sock_no_ioctl,
280	.listen		=	sock_no_listen,
281	.shutdown	=	sock_no_shutdown,
282	.mmap		=	sock_no_mmap,
283	.bind		=	sock_no_bind,
284	.accept		=	sock_no_accept,
285
286	.release	=	af_alg_release,
287	.sendmsg	=	skcipher_sendmsg_nokey,
288	.sendpage	=	skcipher_sendpage_nokey,
289	.recvmsg	=	skcipher_recvmsg_nokey,
290	.poll		=	af_alg_poll,
291};
292
293static void *skcipher_bind(const char *name, u32 type, u32 mask)
294{
295	return crypto_alloc_skcipher(name, type, mask);
296}
297
298static void skcipher_release(void *private)
299{
300	crypto_free_skcipher(private);
301}
302
303static int skcipher_setkey(void *private, const u8 *key, unsigned int keylen)
304{
305	return crypto_skcipher_setkey(private, key, keylen);
306}
307
308static void skcipher_sock_destruct(struct sock *sk)
309{
310	struct alg_sock *ask = alg_sk(sk);
311	struct af_alg_ctx *ctx = ask->private;
312	struct sock *psk = ask->parent;
313	struct alg_sock *pask = alg_sk(psk);
314	struct crypto_skcipher *tfm = pask->private;
315
316	af_alg_pull_tsgl(sk, ctx->used, NULL, 0);
317	sock_kzfree_s(sk, ctx->iv, crypto_skcipher_ivsize(tfm));
318	sock_kfree_s(sk, ctx, ctx->len);
319	af_alg_release_parent(sk);
320}
321
322static int skcipher_accept_parent_nokey(void *private, struct sock *sk)
323{
324	struct af_alg_ctx *ctx;
325	struct alg_sock *ask = alg_sk(sk);
326	struct crypto_skcipher *tfm = private;
327	unsigned int len = sizeof(*ctx);
328
329	ctx = sock_kmalloc(sk, len, GFP_KERNEL);
330	if (!ctx)
331		return -ENOMEM;
332	memset(ctx, 0, len);
333
334	ctx->iv = sock_kmalloc(sk, crypto_skcipher_ivsize(tfm),
335			       GFP_KERNEL);
336	if (!ctx->iv) {
337		sock_kfree_s(sk, ctx, len);
338		return -ENOMEM;
339	}
340	memset(ctx->iv, 0, crypto_skcipher_ivsize(tfm));
341
342	INIT_LIST_HEAD(&ctx->tsgl_list);
343	ctx->len = len;
344	crypto_init_wait(&ctx->wait);
345
346	ask->private = ctx;
347
348	sk->sk_destruct = skcipher_sock_destruct;
349
350	return 0;
351}
352
353static int skcipher_accept_parent(void *private, struct sock *sk)
354{
355	struct crypto_skcipher *tfm = private;
356
357	if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
358		return -ENOKEY;
359
360	return skcipher_accept_parent_nokey(private, sk);
361}
362
363static const struct af_alg_type algif_type_skcipher = {
364	.bind		=	skcipher_bind,
365	.release	=	skcipher_release,
366	.setkey		=	skcipher_setkey,
367	.accept		=	skcipher_accept_parent,
368	.accept_nokey	=	skcipher_accept_parent_nokey,
369	.ops		=	&algif_skcipher_ops,
370	.ops_nokey	=	&algif_skcipher_ops_nokey,
371	.name		=	"skcipher",
372	.owner		=	THIS_MODULE
373};
374
375static int __init algif_skcipher_init(void)
376{
377	return af_alg_register_type(&algif_type_skcipher);
378}
379
380static void __exit algif_skcipher_exit(void)
381{
382	int err = af_alg_unregister_type(&algif_type_skcipher);
383	BUG_ON(err);
384}
385
386module_init(algif_skcipher_init);
387module_exit(algif_skcipher_exit);
388MODULE_LICENSE("GPL");
v6.2
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * algif_skcipher: User-space interface for skcipher algorithms
  4 *
  5 * This file provides the user-space API for symmetric key ciphers.
  6 *
  7 * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
  8 *
  9 * The following concept of the memory management is used:
 10 *
 11 * The kernel maintains two SGLs, the TX SGL and the RX SGL. The TX SGL is
 12 * filled by user space with the data submitted via sendpage/sendmsg. Filling
 13 * up the TX SGL does not cause a crypto operation -- the data will only be
 14 * tracked by the kernel. Upon receipt of one recvmsg call, the caller must
 15 * provide a buffer which is tracked with the RX SGL.
 16 *
 17 * During the processing of the recvmsg operation, the cipher request is
 18 * allocated and prepared. As part of the recvmsg operation, the processed
 19 * TX buffers are extracted from the TX SGL into a separate SGL.
 20 *
 21 * After the completion of the crypto operation, the RX SGL and the cipher
 22 * request is released. The extracted TX SGL parts are released together with
 23 * the RX SGL release.
 24 */
 25
 26#include <crypto/scatterwalk.h>
 27#include <crypto/skcipher.h>
 28#include <crypto/if_alg.h>
 29#include <linux/init.h>
 30#include <linux/list.h>
 31#include <linux/kernel.h>
 32#include <linux/mm.h>
 33#include <linux/module.h>
 34#include <linux/net.h>
 35#include <net/sock.h>
 36
 37static int skcipher_sendmsg(struct socket *sock, struct msghdr *msg,
 38			    size_t size)
 39{
 40	struct sock *sk = sock->sk;
 41	struct alg_sock *ask = alg_sk(sk);
 42	struct sock *psk = ask->parent;
 43	struct alg_sock *pask = alg_sk(psk);
 44	struct crypto_skcipher *tfm = pask->private;
 45	unsigned ivsize = crypto_skcipher_ivsize(tfm);
 46
 47	return af_alg_sendmsg(sock, msg, size, ivsize);
 48}
 49
 50static int _skcipher_recvmsg(struct socket *sock, struct msghdr *msg,
 51			     size_t ignored, int flags)
 52{
 53	struct sock *sk = sock->sk;
 54	struct alg_sock *ask = alg_sk(sk);
 55	struct sock *psk = ask->parent;
 56	struct alg_sock *pask = alg_sk(psk);
 57	struct af_alg_ctx *ctx = ask->private;
 58	struct crypto_skcipher *tfm = pask->private;
 59	unsigned int bs = crypto_skcipher_chunksize(tfm);
 60	struct af_alg_async_req *areq;
 61	int err = 0;
 62	size_t len = 0;
 63
 64	if (!ctx->init || (ctx->more && ctx->used < bs)) {
 65		err = af_alg_wait_for_data(sk, flags, bs);
 66		if (err)
 67			return err;
 68	}
 69
 70	/* Allocate cipher request for current operation. */
 71	areq = af_alg_alloc_areq(sk, sizeof(struct af_alg_async_req) +
 72				     crypto_skcipher_reqsize(tfm));
 73	if (IS_ERR(areq))
 74		return PTR_ERR(areq);
 75
 76	/* convert iovecs of output buffers into RX SGL */
 77	err = af_alg_get_rsgl(sk, msg, flags, areq, ctx->used, &len);
 78	if (err)
 79		goto free;
 80
 81	/*
 82	 * If more buffers are to be expected to be processed, process only
 83	 * full block size buffers.
 84	 */
 85	if (ctx->more || len < ctx->used)
 86		len -= len % bs;
 87
 88	/*
 89	 * Create a per request TX SGL for this request which tracks the
 90	 * SG entries from the global TX SGL.
 91	 */
 92	areq->tsgl_entries = af_alg_count_tsgl(sk, len, 0);
 93	if (!areq->tsgl_entries)
 94		areq->tsgl_entries = 1;
 95	areq->tsgl = sock_kmalloc(sk, array_size(sizeof(*areq->tsgl),
 96						 areq->tsgl_entries),
 97				  GFP_KERNEL);
 98	if (!areq->tsgl) {
 99		err = -ENOMEM;
100		goto free;
101	}
102	sg_init_table(areq->tsgl, areq->tsgl_entries);
103	af_alg_pull_tsgl(sk, len, areq->tsgl, 0);
104
105	/* Initialize the crypto operation */
106	skcipher_request_set_tfm(&areq->cra_u.skcipher_req, tfm);
107	skcipher_request_set_crypt(&areq->cra_u.skcipher_req, areq->tsgl,
108				   areq->first_rsgl.sgl.sg, len, ctx->iv);
109
110	if (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) {
111		/* AIO operation */
112		sock_hold(sk);
113		areq->iocb = msg->msg_iocb;
114
115		/* Remember output size that will be generated. */
116		areq->outlen = len;
117
118		skcipher_request_set_callback(&areq->cra_u.skcipher_req,
119					      CRYPTO_TFM_REQ_MAY_SLEEP,
120					      af_alg_async_cb, areq);
121		err = ctx->enc ?
122			crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) :
123			crypto_skcipher_decrypt(&areq->cra_u.skcipher_req);
124
125		/* AIO operation in progress */
126		if (err == -EINPROGRESS)
127			return -EIOCBQUEUED;
128
129		sock_put(sk);
130	} else {
131		/* Synchronous operation */
132		skcipher_request_set_callback(&areq->cra_u.skcipher_req,
133					      CRYPTO_TFM_REQ_MAY_SLEEP |
134					      CRYPTO_TFM_REQ_MAY_BACKLOG,
135					      crypto_req_done, &ctx->wait);
136		err = crypto_wait_req(ctx->enc ?
137			crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) :
138			crypto_skcipher_decrypt(&areq->cra_u.skcipher_req),
139						 &ctx->wait);
140	}
141
142
143free:
144	af_alg_free_resources(areq);
145
146	return err ? err : len;
147}
148
149static int skcipher_recvmsg(struct socket *sock, struct msghdr *msg,
150			    size_t ignored, int flags)
151{
152	struct sock *sk = sock->sk;
153	int ret = 0;
154
155	lock_sock(sk);
156	while (msg_data_left(msg)) {
157		int err = _skcipher_recvmsg(sock, msg, ignored, flags);
158
159		/*
160		 * This error covers -EIOCBQUEUED which implies that we can
161		 * only handle one AIO request. If the caller wants to have
162		 * multiple AIO requests in parallel, he must make multiple
163		 * separate AIO calls.
164		 *
165		 * Also return the error if no data has been processed so far.
166		 */
167		if (err <= 0) {
168			if (err == -EIOCBQUEUED || !ret)
169				ret = err;
170			goto out;
171		}
172
173		ret += err;
174	}
175
176out:
177	af_alg_wmem_wakeup(sk);
178	release_sock(sk);
179	return ret;
180}
181
182static struct proto_ops algif_skcipher_ops = {
183	.family		=	PF_ALG,
184
185	.connect	=	sock_no_connect,
186	.socketpair	=	sock_no_socketpair,
187	.getname	=	sock_no_getname,
188	.ioctl		=	sock_no_ioctl,
189	.listen		=	sock_no_listen,
190	.shutdown	=	sock_no_shutdown,
191	.mmap		=	sock_no_mmap,
192	.bind		=	sock_no_bind,
193	.accept		=	sock_no_accept,
194
195	.release	=	af_alg_release,
196	.sendmsg	=	skcipher_sendmsg,
197	.sendpage	=	af_alg_sendpage,
198	.recvmsg	=	skcipher_recvmsg,
199	.poll		=	af_alg_poll,
200};
201
202static int skcipher_check_key(struct socket *sock)
203{
204	int err = 0;
205	struct sock *psk;
206	struct alg_sock *pask;
207	struct crypto_skcipher *tfm;
208	struct sock *sk = sock->sk;
209	struct alg_sock *ask = alg_sk(sk);
210
211	lock_sock(sk);
212	if (!atomic_read(&ask->nokey_refcnt))
213		goto unlock_child;
214
215	psk = ask->parent;
216	pask = alg_sk(ask->parent);
217	tfm = pask->private;
218
219	err = -ENOKEY;
220	lock_sock_nested(psk, SINGLE_DEPTH_NESTING);
221	if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
222		goto unlock;
223
224	atomic_dec(&pask->nokey_refcnt);
225	atomic_set(&ask->nokey_refcnt, 0);
226
227	err = 0;
228
229unlock:
230	release_sock(psk);
231unlock_child:
232	release_sock(sk);
233
234	return err;
235}
236
237static int skcipher_sendmsg_nokey(struct socket *sock, struct msghdr *msg,
238				  size_t size)
239{
240	int err;
241
242	err = skcipher_check_key(sock);
243	if (err)
244		return err;
245
246	return skcipher_sendmsg(sock, msg, size);
247}
248
249static ssize_t skcipher_sendpage_nokey(struct socket *sock, struct page *page,
250				       int offset, size_t size, int flags)
251{
252	int err;
253
254	err = skcipher_check_key(sock);
255	if (err)
256		return err;
257
258	return af_alg_sendpage(sock, page, offset, size, flags);
259}
260
261static int skcipher_recvmsg_nokey(struct socket *sock, struct msghdr *msg,
262				  size_t ignored, int flags)
263{
264	int err;
265
266	err = skcipher_check_key(sock);
267	if (err)
268		return err;
269
270	return skcipher_recvmsg(sock, msg, ignored, flags);
271}
272
273static struct proto_ops algif_skcipher_ops_nokey = {
274	.family		=	PF_ALG,
275
276	.connect	=	sock_no_connect,
277	.socketpair	=	sock_no_socketpair,
278	.getname	=	sock_no_getname,
279	.ioctl		=	sock_no_ioctl,
280	.listen		=	sock_no_listen,
281	.shutdown	=	sock_no_shutdown,
282	.mmap		=	sock_no_mmap,
283	.bind		=	sock_no_bind,
284	.accept		=	sock_no_accept,
285
286	.release	=	af_alg_release,
287	.sendmsg	=	skcipher_sendmsg_nokey,
288	.sendpage	=	skcipher_sendpage_nokey,
289	.recvmsg	=	skcipher_recvmsg_nokey,
290	.poll		=	af_alg_poll,
291};
292
293static void *skcipher_bind(const char *name, u32 type, u32 mask)
294{
295	return crypto_alloc_skcipher(name, type, mask);
296}
297
298static void skcipher_release(void *private)
299{
300	crypto_free_skcipher(private);
301}
302
303static int skcipher_setkey(void *private, const u8 *key, unsigned int keylen)
304{
305	return crypto_skcipher_setkey(private, key, keylen);
306}
307
308static void skcipher_sock_destruct(struct sock *sk)
309{
310	struct alg_sock *ask = alg_sk(sk);
311	struct af_alg_ctx *ctx = ask->private;
312	struct sock *psk = ask->parent;
313	struct alg_sock *pask = alg_sk(psk);
314	struct crypto_skcipher *tfm = pask->private;
315
316	af_alg_pull_tsgl(sk, ctx->used, NULL, 0);
317	sock_kzfree_s(sk, ctx->iv, crypto_skcipher_ivsize(tfm));
318	sock_kfree_s(sk, ctx, ctx->len);
319	af_alg_release_parent(sk);
320}
321
322static int skcipher_accept_parent_nokey(void *private, struct sock *sk)
323{
324	struct af_alg_ctx *ctx;
325	struct alg_sock *ask = alg_sk(sk);
326	struct crypto_skcipher *tfm = private;
327	unsigned int len = sizeof(*ctx);
328
329	ctx = sock_kmalloc(sk, len, GFP_KERNEL);
330	if (!ctx)
331		return -ENOMEM;
332	memset(ctx, 0, len);
333
334	ctx->iv = sock_kmalloc(sk, crypto_skcipher_ivsize(tfm),
335			       GFP_KERNEL);
336	if (!ctx->iv) {
337		sock_kfree_s(sk, ctx, len);
338		return -ENOMEM;
339	}
340	memset(ctx->iv, 0, crypto_skcipher_ivsize(tfm));
341
342	INIT_LIST_HEAD(&ctx->tsgl_list);
343	ctx->len = len;
344	crypto_init_wait(&ctx->wait);
345
346	ask->private = ctx;
347
348	sk->sk_destruct = skcipher_sock_destruct;
349
350	return 0;
351}
352
353static int skcipher_accept_parent(void *private, struct sock *sk)
354{
355	struct crypto_skcipher *tfm = private;
356
357	if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
358		return -ENOKEY;
359
360	return skcipher_accept_parent_nokey(private, sk);
361}
362
363static const struct af_alg_type algif_type_skcipher = {
364	.bind		=	skcipher_bind,
365	.release	=	skcipher_release,
366	.setkey		=	skcipher_setkey,
367	.accept		=	skcipher_accept_parent,
368	.accept_nokey	=	skcipher_accept_parent_nokey,
369	.ops		=	&algif_skcipher_ops,
370	.ops_nokey	=	&algif_skcipher_ops_nokey,
371	.name		=	"skcipher",
372	.owner		=	THIS_MODULE
373};
374
375static int __init algif_skcipher_init(void)
376{
377	return af_alg_register_type(&algif_type_skcipher);
378}
379
380static void __exit algif_skcipher_exit(void)
381{
382	int err = af_alg_unregister_type(&algif_type_skcipher);
383	BUG_ON(err);
384}
385
386module_init(algif_skcipher_init);
387module_exit(algif_skcipher_exit);
388MODULE_LICENSE("GPL");