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v5.4
  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_blocksize(tfm);
 60	struct af_alg_async_req *areq;
 
 61	int err = 0;
 62	size_t len = 0;
 63
 64	if (!ctx->used) {
 65		err = af_alg_wait_for_data(sk, flags);
 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, -1, &len);
 78	if (err)
 79		goto free;
 80
 81	/* Process only as much RX buffers for which we have TX data */
 82	if (len > ctx->used)
 83		len = ctx->used;
 84
 85	/*
 86	 * If more buffers are to be expected to be processed, process only
 87	 * full block size buffers.
 88	 */
 89	if (ctx->more || len < ctx->used)
 90		len -= len % bs;
 
 
 91
 92	/*
 93	 * Create a per request TX SGL for this request which tracks the
 94	 * SG entries from the global TX SGL.
 95	 */
 96	areq->tsgl_entries = af_alg_count_tsgl(sk, len, 0);
 97	if (!areq->tsgl_entries)
 98		areq->tsgl_entries = 1;
 99	areq->tsgl = sock_kmalloc(sk, array_size(sizeof(*areq->tsgl),
100						 areq->tsgl_entries),
101				  GFP_KERNEL);
102	if (!areq->tsgl) {
103		err = -ENOMEM;
104		goto free;
105	}
106	sg_init_table(areq->tsgl, areq->tsgl_entries);
107	af_alg_pull_tsgl(sk, len, areq->tsgl, 0);
108
109	/* Initialize the crypto operation */
110	skcipher_request_set_tfm(&areq->cra_u.skcipher_req, tfm);
111	skcipher_request_set_crypt(&areq->cra_u.skcipher_req, areq->tsgl,
112				   areq->first_rsgl.sgl.sg, len, ctx->iv);
 
 
 
 
 
 
 
 
 
 
113
114	if (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) {
115		/* AIO operation */
116		sock_hold(sk);
117		areq->iocb = msg->msg_iocb;
118
119		/* Remember output size that will be generated. */
120		areq->outlen = len;
121
122		skcipher_request_set_callback(&areq->cra_u.skcipher_req,
 
123					      CRYPTO_TFM_REQ_MAY_SLEEP,
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);
128
129		/* AIO operation in progress */
130		if (err == -EINPROGRESS || err == -EBUSY)
131			return -EIOCBQUEUED;
132
133		sock_put(sk);
134	} else {
135		/* Synchronous operation */
136		skcipher_request_set_callback(&areq->cra_u.skcipher_req,
 
137					      CRYPTO_TFM_REQ_MAY_SLEEP |
138					      CRYPTO_TFM_REQ_MAY_BACKLOG,
139					      crypto_req_done, &ctx->wait);
140		err = crypto_wait_req(ctx->enc ?
141			crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) :
142			crypto_skcipher_decrypt(&areq->cra_u.skcipher_req),
143						 &ctx->wait);
144	}
145
 
 
 
 
146
147free:
148	af_alg_free_resources(areq);
149
150	return err ? err : len;
151}
152
153static int skcipher_recvmsg(struct socket *sock, struct msghdr *msg,
154			    size_t ignored, int flags)
155{
156	struct sock *sk = sock->sk;
157	int ret = 0;
158
159	lock_sock(sk);
160	while (msg_data_left(msg)) {
161		int err = _skcipher_recvmsg(sock, msg, ignored, flags);
162
163		/*
164		 * This error covers -EIOCBQUEUED which implies that we can
165		 * only handle one AIO request. If the caller wants to have
166		 * multiple AIO requests in parallel, he must make multiple
167		 * separate AIO calls.
168		 *
169		 * Also return the error if no data has been processed so far.
170		 */
171		if (err <= 0) {
172			if (err == -EIOCBQUEUED || !ret)
173				ret = err;
174			goto out;
175		}
176
177		ret += err;
178	}
179
180out:
181	af_alg_wmem_wakeup(sk);
182	release_sock(sk);
183	return ret;
184}
185
186static struct proto_ops algif_skcipher_ops = {
187	.family		=	PF_ALG,
188
189	.connect	=	sock_no_connect,
190	.socketpair	=	sock_no_socketpair,
191	.getname	=	sock_no_getname,
192	.ioctl		=	sock_no_ioctl,
193	.listen		=	sock_no_listen,
194	.shutdown	=	sock_no_shutdown,
195	.getsockopt	=	sock_no_getsockopt,
196	.mmap		=	sock_no_mmap,
197	.bind		=	sock_no_bind,
198	.accept		=	sock_no_accept,
199	.setsockopt	=	sock_no_setsockopt,
200
201	.release	=	af_alg_release,
202	.sendmsg	=	skcipher_sendmsg,
203	.sendpage	=	af_alg_sendpage,
204	.recvmsg	=	skcipher_recvmsg,
205	.poll		=	af_alg_poll,
206};
207
208static int skcipher_check_key(struct socket *sock)
209{
210	int err = 0;
211	struct sock *psk;
212	struct alg_sock *pask;
213	struct crypto_skcipher *tfm;
214	struct sock *sk = sock->sk;
215	struct alg_sock *ask = alg_sk(sk);
216
217	lock_sock(sk);
218	if (ask->refcnt)
219		goto unlock_child;
220
221	psk = ask->parent;
222	pask = alg_sk(ask->parent);
223	tfm = pask->private;
224
225	err = -ENOKEY;
226	lock_sock_nested(psk, SINGLE_DEPTH_NESTING);
227	if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
228		goto unlock;
229
230	if (!pask->refcnt++)
231		sock_hold(psk);
232
233	ask->refcnt = 1;
234	sock_put(psk);
235
236	err = 0;
237
238unlock:
239	release_sock(psk);
240unlock_child:
241	release_sock(sk);
242
243	return err;
244}
245
246static int skcipher_sendmsg_nokey(struct socket *sock, struct msghdr *msg,
247				  size_t size)
248{
249	int err;
250
251	err = skcipher_check_key(sock);
252	if (err)
253		return err;
254
255	return skcipher_sendmsg(sock, msg, size);
256}
257
258static ssize_t skcipher_sendpage_nokey(struct socket *sock, struct page *page,
259				       int offset, size_t size, int flags)
260{
261	int err;
262
263	err = skcipher_check_key(sock);
264	if (err)
265		return err;
266
267	return af_alg_sendpage(sock, page, offset, size, flags);
268}
269
270static int skcipher_recvmsg_nokey(struct socket *sock, struct msghdr *msg,
271				  size_t ignored, int flags)
272{
273	int err;
274
275	err = skcipher_check_key(sock);
276	if (err)
277		return err;
278
279	return skcipher_recvmsg(sock, msg, ignored, flags);
280}
281
282static struct proto_ops algif_skcipher_ops_nokey = {
283	.family		=	PF_ALG,
284
285	.connect	=	sock_no_connect,
286	.socketpair	=	sock_no_socketpair,
287	.getname	=	sock_no_getname,
288	.ioctl		=	sock_no_ioctl,
289	.listen		=	sock_no_listen,
290	.shutdown	=	sock_no_shutdown,
291	.getsockopt	=	sock_no_getsockopt,
292	.mmap		=	sock_no_mmap,
293	.bind		=	sock_no_bind,
294	.accept		=	sock_no_accept,
295	.setsockopt	=	sock_no_setsockopt,
296
297	.release	=	af_alg_release,
298	.sendmsg	=	skcipher_sendmsg_nokey,
299	.sendpage	=	skcipher_sendpage_nokey,
300	.recvmsg	=	skcipher_recvmsg_nokey,
301	.poll		=	af_alg_poll,
302};
303
304static void *skcipher_bind(const char *name, u32 type, u32 mask)
305{
306	return crypto_alloc_skcipher(name, type, mask);
307}
308
309static void skcipher_release(void *private)
310{
311	crypto_free_skcipher(private);
312}
313
314static int skcipher_setkey(void *private, const u8 *key, unsigned int keylen)
315{
316	return crypto_skcipher_setkey(private, key, keylen);
317}
318
319static void skcipher_sock_destruct(struct sock *sk)
320{
321	struct alg_sock *ask = alg_sk(sk);
322	struct af_alg_ctx *ctx = ask->private;
323	struct sock *psk = ask->parent;
324	struct alg_sock *pask = alg_sk(psk);
325	struct crypto_skcipher *tfm = pask->private;
326
327	af_alg_pull_tsgl(sk, ctx->used, NULL, 0);
328	sock_kzfree_s(sk, ctx->iv, crypto_skcipher_ivsize(tfm));
 
 
329	sock_kfree_s(sk, ctx, ctx->len);
330	af_alg_release_parent(sk);
331}
332
333static int skcipher_accept_parent_nokey(void *private, struct sock *sk)
334{
335	struct af_alg_ctx *ctx;
336	struct alg_sock *ask = alg_sk(sk);
337	struct crypto_skcipher *tfm = private;
338	unsigned int len = sizeof(*ctx);
339
340	ctx = sock_kmalloc(sk, len, GFP_KERNEL);
341	if (!ctx)
342		return -ENOMEM;
 
343
344	ctx->iv = sock_kmalloc(sk, crypto_skcipher_ivsize(tfm),
345			       GFP_KERNEL);
346	if (!ctx->iv) {
347		sock_kfree_s(sk, ctx, len);
348		return -ENOMEM;
349	}
350
351	memset(ctx->iv, 0, crypto_skcipher_ivsize(tfm));
352
353	INIT_LIST_HEAD(&ctx->tsgl_list);
354	ctx->len = len;
355	ctx->used = 0;
356	atomic_set(&ctx->rcvused, 0);
357	ctx->more = 0;
358	ctx->merge = 0;
359	ctx->enc = 0;
360	crypto_init_wait(&ctx->wait);
361
362	ask->private = ctx;
363
364	sk->sk_destruct = skcipher_sock_destruct;
365
366	return 0;
367}
368
369static int skcipher_accept_parent(void *private, struct sock *sk)
370{
371	struct crypto_skcipher *tfm = private;
372
373	if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
374		return -ENOKEY;
375
376	return skcipher_accept_parent_nokey(private, sk);
377}
378
379static const struct af_alg_type algif_type_skcipher = {
380	.bind		=	skcipher_bind,
381	.release	=	skcipher_release,
382	.setkey		=	skcipher_setkey,
383	.accept		=	skcipher_accept_parent,
384	.accept_nokey	=	skcipher_accept_parent_nokey,
385	.ops		=	&algif_skcipher_ops,
386	.ops_nokey	=	&algif_skcipher_ops_nokey,
387	.name		=	"skcipher",
388	.owner		=	THIS_MODULE
389};
390
391static int __init algif_skcipher_init(void)
392{
393	return af_alg_register_type(&algif_type_skcipher);
394}
395
396static void __exit algif_skcipher_exit(void)
397{
398	int err = af_alg_unregister_type(&algif_type_skcipher);
399	BUG_ON(err);
400}
401
402module_init(algif_skcipher_init);
403module_exit(algif_skcipher_exit);
 
404MODULE_LICENSE("GPL");
v6.13.7
  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 sendmsg. Filling up the TX
 13 * SGL does not cause a crypto operation -- the data will only be tracked by
 14 * the kernel. Upon receipt of one recvmsg call, the caller must provide a
 15 * 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 algif_skcipher_export(struct sock *sk, struct skcipher_request *req)
 51{
 52	struct alg_sock *ask = alg_sk(sk);
 53	struct crypto_skcipher *tfm;
 54	struct af_alg_ctx *ctx;
 55	struct alg_sock *pask;
 56	unsigned statesize;
 57	struct sock *psk;
 58	int err;
 59
 60	if (!(req->base.flags & CRYPTO_SKCIPHER_REQ_NOTFINAL))
 61		return 0;
 62
 63	ctx = ask->private;
 64	psk = ask->parent;
 65	pask = alg_sk(psk);
 66	tfm = pask->private;
 67
 68	statesize = crypto_skcipher_statesize(tfm);
 69	ctx->state = sock_kmalloc(sk, statesize, GFP_ATOMIC);
 70	if (!ctx->state)
 71		return -ENOMEM;
 72
 73	err = crypto_skcipher_export(req, ctx->state);
 74	if (err) {
 75		sock_kzfree_s(sk, ctx->state, statesize);
 76		ctx->state = NULL;
 77	}
 78
 79	return err;
 80}
 81
 82static void algif_skcipher_done(void *data, int err)
 83{
 84	struct af_alg_async_req *areq = data;
 85	struct sock *sk = areq->sk;
 86
 87	if (err)
 88		goto out;
 89
 90	err = algif_skcipher_export(sk, &areq->cra_u.skcipher_req);
 91
 92out:
 93	af_alg_async_cb(data, err);
 94}
 95
 96static int _skcipher_recvmsg(struct socket *sock, struct msghdr *msg,
 97			     size_t ignored, int flags)
 98{
 99	struct sock *sk = sock->sk;
100	struct alg_sock *ask = alg_sk(sk);
101	struct sock *psk = ask->parent;
102	struct alg_sock *pask = alg_sk(psk);
103	struct af_alg_ctx *ctx = ask->private;
104	struct crypto_skcipher *tfm = pask->private;
105	unsigned int bs = crypto_skcipher_chunksize(tfm);
106	struct af_alg_async_req *areq;
107	unsigned cflags = 0;
108	int err = 0;
109	size_t len = 0;
110
111	if (!ctx->init || (ctx->more && ctx->used < bs)) {
112		err = af_alg_wait_for_data(sk, flags, bs);
113		if (err)
114			return err;
115	}
116
117	/* Allocate cipher request for current operation. */
118	areq = af_alg_alloc_areq(sk, sizeof(struct af_alg_async_req) +
119				     crypto_skcipher_reqsize(tfm));
120	if (IS_ERR(areq))
121		return PTR_ERR(areq);
122
123	/* convert iovecs of output buffers into RX SGL */
124	err = af_alg_get_rsgl(sk, msg, flags, areq, ctx->used, &len);
125	if (err)
126		goto free;
127
 
 
 
 
128	/*
129	 * If more buffers are to be expected to be processed, process only
130	 * full block size buffers.
131	 */
132	if (ctx->more || len < ctx->used) {
133		len -= len % bs;
134		cflags |= CRYPTO_SKCIPHER_REQ_NOTFINAL;
135	}
136
137	/*
138	 * Create a per request TX SGL for this request which tracks the
139	 * SG entries from the global TX SGL.
140	 */
141	areq->tsgl_entries = af_alg_count_tsgl(sk, len, 0);
142	if (!areq->tsgl_entries)
143		areq->tsgl_entries = 1;
144	areq->tsgl = sock_kmalloc(sk, array_size(sizeof(*areq->tsgl),
145						 areq->tsgl_entries),
146				  GFP_KERNEL);
147	if (!areq->tsgl) {
148		err = -ENOMEM;
149		goto free;
150	}
151	sg_init_table(areq->tsgl, areq->tsgl_entries);
152	af_alg_pull_tsgl(sk, len, areq->tsgl, 0);
153
154	/* Initialize the crypto operation */
155	skcipher_request_set_tfm(&areq->cra_u.skcipher_req, tfm);
156	skcipher_request_set_crypt(&areq->cra_u.skcipher_req, areq->tsgl,
157				   areq->first_rsgl.sgl.sgt.sgl, len, ctx->iv);
158
159	if (ctx->state) {
160		err = crypto_skcipher_import(&areq->cra_u.skcipher_req,
161					     ctx->state);
162		sock_kzfree_s(sk, ctx->state, crypto_skcipher_statesize(tfm));
163		ctx->state = NULL;
164		if (err)
165			goto free;
166		cflags |= CRYPTO_SKCIPHER_REQ_CONT;
167	}
168
169	if (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) {
170		/* AIO operation */
171		sock_hold(sk);
172		areq->iocb = msg->msg_iocb;
173
174		/* Remember output size that will be generated. */
175		areq->outlen = len;
176
177		skcipher_request_set_callback(&areq->cra_u.skcipher_req,
178					      cflags |
179					      CRYPTO_TFM_REQ_MAY_SLEEP,
180					      algif_skcipher_done, areq);
181		err = ctx->enc ?
182			crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) :
183			crypto_skcipher_decrypt(&areq->cra_u.skcipher_req);
184
185		/* AIO operation in progress */
186		if (err == -EINPROGRESS)
187			return -EIOCBQUEUED;
188
189		sock_put(sk);
190	} else {
191		/* Synchronous operation */
192		skcipher_request_set_callback(&areq->cra_u.skcipher_req,
193					      cflags |
194					      CRYPTO_TFM_REQ_MAY_SLEEP |
195					      CRYPTO_TFM_REQ_MAY_BACKLOG,
196					      crypto_req_done, &ctx->wait);
197		err = crypto_wait_req(ctx->enc ?
198			crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) :
199			crypto_skcipher_decrypt(&areq->cra_u.skcipher_req),
200						 &ctx->wait);
 
201
202		if (!err)
203			err = algif_skcipher_export(
204				sk, &areq->cra_u.skcipher_req);
205	}
206
207free:
208	af_alg_free_resources(areq);
209
210	return err ? err : len;
211}
212
213static int skcipher_recvmsg(struct socket *sock, struct msghdr *msg,
214			    size_t ignored, int flags)
215{
216	struct sock *sk = sock->sk;
217	int ret = 0;
218
219	lock_sock(sk);
220	while (msg_data_left(msg)) {
221		int err = _skcipher_recvmsg(sock, msg, ignored, flags);
222
223		/*
224		 * This error covers -EIOCBQUEUED which implies that we can
225		 * only handle one AIO request. If the caller wants to have
226		 * multiple AIO requests in parallel, he must make multiple
227		 * separate AIO calls.
228		 *
229		 * Also return the error if no data has been processed so far.
230		 */
231		if (err <= 0) {
232			if (err == -EIOCBQUEUED || !ret)
233				ret = err;
234			goto out;
235		}
236
237		ret += err;
238	}
239
240out:
241	af_alg_wmem_wakeup(sk);
242	release_sock(sk);
243	return ret;
244}
245
246static struct proto_ops algif_skcipher_ops = {
247	.family		=	PF_ALG,
248
249	.connect	=	sock_no_connect,
250	.socketpair	=	sock_no_socketpair,
251	.getname	=	sock_no_getname,
252	.ioctl		=	sock_no_ioctl,
253	.listen		=	sock_no_listen,
254	.shutdown	=	sock_no_shutdown,
 
255	.mmap		=	sock_no_mmap,
256	.bind		=	sock_no_bind,
257	.accept		=	sock_no_accept,
 
258
259	.release	=	af_alg_release,
260	.sendmsg	=	skcipher_sendmsg,
 
261	.recvmsg	=	skcipher_recvmsg,
262	.poll		=	af_alg_poll,
263};
264
265static int skcipher_check_key(struct socket *sock)
266{
267	int err = 0;
268	struct sock *psk;
269	struct alg_sock *pask;
270	struct crypto_skcipher *tfm;
271	struct sock *sk = sock->sk;
272	struct alg_sock *ask = alg_sk(sk);
273
274	lock_sock(sk);
275	if (!atomic_read(&ask->nokey_refcnt))
276		goto unlock_child;
277
278	psk = ask->parent;
279	pask = alg_sk(ask->parent);
280	tfm = pask->private;
281
282	err = -ENOKEY;
283	lock_sock_nested(psk, SINGLE_DEPTH_NESTING);
284	if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
285		goto unlock;
286
287	atomic_dec(&pask->nokey_refcnt);
288	atomic_set(&ask->nokey_refcnt, 0);
 
 
 
289
290	err = 0;
291
292unlock:
293	release_sock(psk);
294unlock_child:
295	release_sock(sk);
296
297	return err;
298}
299
300static int skcipher_sendmsg_nokey(struct socket *sock, struct msghdr *msg,
301				  size_t size)
302{
303	int err;
304
305	err = skcipher_check_key(sock);
306	if (err)
307		return err;
308
309	return skcipher_sendmsg(sock, msg, size);
310}
311
 
 
 
 
 
 
 
 
 
 
 
 
312static int skcipher_recvmsg_nokey(struct socket *sock, struct msghdr *msg,
313				  size_t ignored, int flags)
314{
315	int err;
316
317	err = skcipher_check_key(sock);
318	if (err)
319		return err;
320
321	return skcipher_recvmsg(sock, msg, ignored, flags);
322}
323
324static struct proto_ops algif_skcipher_ops_nokey = {
325	.family		=	PF_ALG,
326
327	.connect	=	sock_no_connect,
328	.socketpair	=	sock_no_socketpair,
329	.getname	=	sock_no_getname,
330	.ioctl		=	sock_no_ioctl,
331	.listen		=	sock_no_listen,
332	.shutdown	=	sock_no_shutdown,
 
333	.mmap		=	sock_no_mmap,
334	.bind		=	sock_no_bind,
335	.accept		=	sock_no_accept,
 
336
337	.release	=	af_alg_release,
338	.sendmsg	=	skcipher_sendmsg_nokey,
 
339	.recvmsg	=	skcipher_recvmsg_nokey,
340	.poll		=	af_alg_poll,
341};
342
343static void *skcipher_bind(const char *name, u32 type, u32 mask)
344{
345	return crypto_alloc_skcipher(name, type, mask);
346}
347
348static void skcipher_release(void *private)
349{
350	crypto_free_skcipher(private);
351}
352
353static int skcipher_setkey(void *private, const u8 *key, unsigned int keylen)
354{
355	return crypto_skcipher_setkey(private, key, keylen);
356}
357
358static void skcipher_sock_destruct(struct sock *sk)
359{
360	struct alg_sock *ask = alg_sk(sk);
361	struct af_alg_ctx *ctx = ask->private;
362	struct sock *psk = ask->parent;
363	struct alg_sock *pask = alg_sk(psk);
364	struct crypto_skcipher *tfm = pask->private;
365
366	af_alg_pull_tsgl(sk, ctx->used, NULL, 0);
367	sock_kzfree_s(sk, ctx->iv, crypto_skcipher_ivsize(tfm));
368	if (ctx->state)
369		sock_kzfree_s(sk, ctx->state, crypto_skcipher_statesize(tfm));
370	sock_kfree_s(sk, ctx, ctx->len);
371	af_alg_release_parent(sk);
372}
373
374static int skcipher_accept_parent_nokey(void *private, struct sock *sk)
375{
376	struct af_alg_ctx *ctx;
377	struct alg_sock *ask = alg_sk(sk);
378	struct crypto_skcipher *tfm = private;
379	unsigned int len = sizeof(*ctx);
380
381	ctx = sock_kmalloc(sk, len, GFP_KERNEL);
382	if (!ctx)
383		return -ENOMEM;
384	memset(ctx, 0, len);
385
386	ctx->iv = sock_kmalloc(sk, crypto_skcipher_ivsize(tfm),
387			       GFP_KERNEL);
388	if (!ctx->iv) {
389		sock_kfree_s(sk, ctx, len);
390		return -ENOMEM;
391	}
 
392	memset(ctx->iv, 0, crypto_skcipher_ivsize(tfm));
393
394	INIT_LIST_HEAD(&ctx->tsgl_list);
395	ctx->len = len;
 
 
 
 
 
396	crypto_init_wait(&ctx->wait);
397
398	ask->private = ctx;
399
400	sk->sk_destruct = skcipher_sock_destruct;
401
402	return 0;
403}
404
405static int skcipher_accept_parent(void *private, struct sock *sk)
406{
407	struct crypto_skcipher *tfm = private;
408
409	if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
410		return -ENOKEY;
411
412	return skcipher_accept_parent_nokey(private, sk);
413}
414
415static const struct af_alg_type algif_type_skcipher = {
416	.bind		=	skcipher_bind,
417	.release	=	skcipher_release,
418	.setkey		=	skcipher_setkey,
419	.accept		=	skcipher_accept_parent,
420	.accept_nokey	=	skcipher_accept_parent_nokey,
421	.ops		=	&algif_skcipher_ops,
422	.ops_nokey	=	&algif_skcipher_ops_nokey,
423	.name		=	"skcipher",
424	.owner		=	THIS_MODULE
425};
426
427static int __init algif_skcipher_init(void)
428{
429	return af_alg_register_type(&algif_type_skcipher);
430}
431
432static void __exit algif_skcipher_exit(void)
433{
434	int err = af_alg_unregister_type(&algif_type_skcipher);
435	BUG_ON(err);
436}
437
438module_init(algif_skcipher_init);
439module_exit(algif_skcipher_exit);
440MODULE_DESCRIPTION("Userspace interface for skcipher algorithms");
441MODULE_LICENSE("GPL");