1 /*
2 * Copyright (C) 2011 Instituto Nokia de Tecnologia
3 *
4 * Authors:
5 * Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
6 * Lauro Ramos Venancio <lauro.venancio@openbossa.org>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, see <http://www.gnu.org/licenses/>.
20 */
21
22 #define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__
23
24 #include <net/tcp_states.h>
25 #include <linux/nfc.h>
26 #include <linux/export.h>
27
28 #include "nfc.h"
29
30 static struct nfc_sock_list raw_sk_list = {
31 .lock = __RW_LOCK_UNLOCKED(raw_sk_list.lock)
32 };
33
34 static void nfc_sock_link(struct nfc_sock_list *l, struct sock *sk)
35 {
36 write_lock(&l->lock);
37 sk_add_node(sk, &l->head);
38 write_unlock(&l->lock);
39 }
40
41 static void nfc_sock_unlink(struct nfc_sock_list *l, struct sock *sk)
42 {
43 write_lock(&l->lock);
44 sk_del_node_init(sk);
45 write_unlock(&l->lock);
46 }
47
48 static void rawsock_write_queue_purge(struct sock *sk)
49 {
50 pr_debug("sk=%p\n", sk);
51
52 spin_lock_bh(&sk->sk_write_queue.lock);
53 __skb_queue_purge(&sk->sk_write_queue);
54 nfc_rawsock(sk)->tx_work_scheduled = false;
55 spin_unlock_bh(&sk->sk_write_queue.lock);
56 }
57
58 static void rawsock_report_error(struct sock *sk, int err)
59 {
60 pr_debug("sk=%p err=%d\n", sk, err);
61
62 sk->sk_shutdown = SHUTDOWN_MASK;
63 sk->sk_err = -err;
64 sk->sk_error_report(sk);
65
66 rawsock_write_queue_purge(sk);
67 }
68
69 static int rawsock_release(struct socket *sock)
70 {
71 struct sock *sk = sock->sk;
72
73 pr_debug("sock=%p sk=%p\n", sock, sk);
74
75 if (!sk)
76 return 0;
77
78 if (sock->type == SOCK_RAW)
79 nfc_sock_unlink(&raw_sk_list, sk);
80
81 sock_orphan(sk);
82 sock_put(sk);
83
84 return 0;
85 }
86
87 static int rawsock_connect(struct socket *sock, struct sockaddr *_addr,
88 int len, int flags)
89 {
90 struct sock *sk = sock->sk;
91 struct sockaddr_nfc *addr = (struct sockaddr_nfc *)_addr;
92 struct nfc_dev *dev;
93 int rc = 0;
94
95 pr_debug("sock=%p sk=%p flags=%d\n", sock, sk, flags);
96
97 if (!addr || len < sizeof(struct sockaddr_nfc) ||
98 addr->sa_family != AF_NFC)
99 return -EINVAL;
100
101 pr_debug("addr dev_idx=%u target_idx=%u protocol=%u\n",
102 addr->dev_idx, addr->target_idx, addr->nfc_protocol);
103
104 lock_sock(sk);
105
106 if (sock->state == SS_CONNECTED) {
107 rc = -EISCONN;
108 goto error;
109 }
110
111 dev = nfc_get_device(addr->dev_idx);
112 if (!dev) {
113 rc = -ENODEV;
114 goto error;
115 }
116
117 if (addr->target_idx > dev->target_next_idx - 1 ||
118 addr->target_idx < dev->target_next_idx - dev->n_targets) {
119 rc = -EINVAL;
120 goto error;
121 }
122
123 rc = nfc_activate_target(dev, addr->target_idx, addr->nfc_protocol);
124 if (rc)
125 goto put_dev;
126
127 nfc_rawsock(sk)->dev = dev;
128 nfc_rawsock(sk)->target_idx = addr->target_idx;
129 sock->state = SS_CONNECTED;
130 sk->sk_state = TCP_ESTABLISHED;
131 sk->sk_state_change(sk);
132
133 release_sock(sk);
134 return 0;
135
136 put_dev:
137 nfc_put_device(dev);
138 error:
139 release_sock(sk);
140 return rc;
141 }
142
143 static int rawsock_add_header(struct sk_buff *skb)
144 {
145 *skb_push(skb, NFC_HEADER_SIZE) = 0;
146
147 return 0;
148 }
149
150 static void rawsock_data_exchange_complete(void *context, struct sk_buff *skb,
151 int err)
152 {
153 struct sock *sk = (struct sock *) context;
154
155 BUG_ON(in_irq());
156
157 pr_debug("sk=%p err=%d\n", sk, err);
158
159 if (err)
160 goto error;
161
162 err = rawsock_add_header(skb);
163 if (err)
164 goto error_skb;
165
166 err = sock_queue_rcv_skb(sk, skb);
167 if (err)
168 goto error_skb;
169
170 spin_lock_bh(&sk->sk_write_queue.lock);
171 if (!skb_queue_empty(&sk->sk_write_queue))
172 schedule_work(&nfc_rawsock(sk)->tx_work);
173 else
174 nfc_rawsock(sk)->tx_work_scheduled = false;
175 spin_unlock_bh(&sk->sk_write_queue.lock);
176
177 sock_put(sk);
178 return;
179
180 error_skb:
181 kfree_skb(skb);
182
183 error:
184 rawsock_report_error(sk, err);
185 sock_put(sk);
186 }
187
188 static void rawsock_tx_work(struct work_struct *work)
189 {
190 struct sock *sk = to_rawsock_sk(work);
191 struct nfc_dev *dev = nfc_rawsock(sk)->dev;
192 u32 target_idx = nfc_rawsock(sk)->target_idx;
193 struct sk_buff *skb;
194 int rc;
195
196 pr_debug("sk=%p target_idx=%u\n", sk, target_idx);
197
198 if (sk->sk_shutdown & SEND_SHUTDOWN) {
199 rawsock_write_queue_purge(sk);
200 return;
201 }
202
203 skb = skb_dequeue(&sk->sk_write_queue);
204
205 sock_hold(sk);
206 rc = nfc_data_exchange(dev, target_idx, skb,
207 rawsock_data_exchange_complete, sk);
208 if (rc) {
209 rawsock_report_error(sk, rc);
210 sock_put(sk);
211 }
212 }
213
214 static int rawsock_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
215 {
216 struct sock *sk = sock->sk;
217 struct nfc_dev *dev = nfc_rawsock(sk)->dev;
218 struct sk_buff *skb;
219 int rc;
220
221 pr_debug("sock=%p sk=%p len=%zu\n", sock, sk, len);
222
223 if (msg->msg_namelen)
224 return -EOPNOTSUPP;
225
226 if (sock->state != SS_CONNECTED)
227 return -ENOTCONN;
228
229 skb = nfc_alloc_send_skb(dev, sk, msg->msg_flags, len, &rc);
230 if (skb == NULL)
231 return rc;
232
233 rc = memcpy_from_msg(skb_put(skb, len), msg, len);
234 if (rc < 0) {
235 kfree_skb(skb);
236 return rc;
237 }
238
239 spin_lock_bh(&sk->sk_write_queue.lock);
240 __skb_queue_tail(&sk->sk_write_queue, skb);
241 if (!nfc_rawsock(sk)->tx_work_scheduled) {
242 schedule_work(&nfc_rawsock(sk)->tx_work);
243 nfc_rawsock(sk)->tx_work_scheduled = true;
244 }
245 spin_unlock_bh(&sk->sk_write_queue.lock);
246
247 return len;
248 }
249
250 static int rawsock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
251 int flags)
252 {
253 int noblock = flags & MSG_DONTWAIT;
254 struct sock *sk = sock->sk;
255 struct sk_buff *skb;
256 int copied;
257 int rc;
258
259 pr_debug("sock=%p sk=%p len=%zu flags=%d\n", sock, sk, len, flags);
260
261 skb = skb_recv_datagram(sk, flags, noblock, &rc);
262 if (!skb)
263 return rc;
264
265 copied = skb->len;
266 if (len < copied) {
267 msg->msg_flags |= MSG_TRUNC;
268 copied = len;
269 }
270
271 rc = skb_copy_datagram_msg(skb, 0, msg, copied);
272
273 skb_free_datagram(sk, skb);
274
275 return rc ? : copied;
276 }
277
278 static const struct proto_ops rawsock_ops = {
279 .family = PF_NFC,
280 .owner = THIS_MODULE,
281 .release = rawsock_release,
282 .bind = sock_no_bind,
283 .connect = rawsock_connect,
284 .socketpair = sock_no_socketpair,
285 .accept = sock_no_accept,
286 .getname = sock_no_getname,
287 .poll = datagram_poll,
288 .ioctl = sock_no_ioctl,
289 .listen = sock_no_listen,
290 .shutdown = sock_no_shutdown,
291 .setsockopt = sock_no_setsockopt,
292 .getsockopt = sock_no_getsockopt,
293 .sendmsg = rawsock_sendmsg,
294 .recvmsg = rawsock_recvmsg,
295 .mmap = sock_no_mmap,
296 };
297
298 static const struct proto_ops rawsock_raw_ops = {
299 .family = PF_NFC,
300 .owner = THIS_MODULE,
301 .release = rawsock_release,
302 .bind = sock_no_bind,
303 .connect = sock_no_connect,
304 .socketpair = sock_no_socketpair,
305 .accept = sock_no_accept,
306 .getname = sock_no_getname,
307 .poll = datagram_poll,
308 .ioctl = sock_no_ioctl,
309 .listen = sock_no_listen,
310 .shutdown = sock_no_shutdown,
311 .setsockopt = sock_no_setsockopt,
312 .getsockopt = sock_no_getsockopt,
313 .sendmsg = sock_no_sendmsg,
314 .recvmsg = rawsock_recvmsg,
315 .mmap = sock_no_mmap,
316 };
317
318 static void rawsock_destruct(struct sock *sk)
319 {
320 pr_debug("sk=%p\n", sk);
321
322 if (sk->sk_state == TCP_ESTABLISHED) {
323 nfc_deactivate_target(nfc_rawsock(sk)->dev,
324 nfc_rawsock(sk)->target_idx,
325 NFC_TARGET_MODE_IDLE);
326 nfc_put_device(nfc_rawsock(sk)->dev);
327 }
328
329 skb_queue_purge(&sk->sk_receive_queue);
330
331 if (!sock_flag(sk, SOCK_DEAD)) {
332 pr_err("Freeing alive NFC raw socket %p\n", sk);
333 return;
334 }
335 }
336
337 static int rawsock_create(struct net *net, struct socket *sock,
338 const struct nfc_protocol *nfc_proto, int kern)
339 {
340 struct sock *sk;
341
342 pr_debug("sock=%p\n", sock);
343
344 if ((sock->type != SOCK_SEQPACKET) && (sock->type != SOCK_RAW))
345 return -ESOCKTNOSUPPORT;
346
347 if (sock->type == SOCK_RAW)
348 sock->ops = &rawsock_raw_ops;
349 else
350 sock->ops = &rawsock_ops;
351
352 sk = sk_alloc(net, PF_NFC, GFP_ATOMIC, nfc_proto->proto, kern);
353 if (!sk)
354 return -ENOMEM;
355
356 sock_init_data(sock, sk);
357 sk->sk_protocol = nfc_proto->id;
358 sk->sk_destruct = rawsock_destruct;
359 sock->state = SS_UNCONNECTED;
360 if (sock->type == SOCK_RAW)
361 nfc_sock_link(&raw_sk_list, sk);
362 else {
363 INIT_WORK(&nfc_rawsock(sk)->tx_work, rawsock_tx_work);
364 nfc_rawsock(sk)->tx_work_scheduled = false;
365 }
366
367 return 0;
368 }
369
370 void nfc_send_to_raw_sock(struct nfc_dev *dev, struct sk_buff *skb,
371 u8 payload_type, u8 direction)
372 {
373 struct sk_buff *skb_copy = NULL, *nskb;
374 struct sock *sk;
375 u8 *data;
376
377 read_lock(&raw_sk_list.lock);
378
379 sk_for_each(sk, &raw_sk_list.head) {
380 if (!skb_copy) {
381 skb_copy = __pskb_copy_fclone(skb, NFC_RAW_HEADER_SIZE,
382 GFP_ATOMIC, true);
383 if (!skb_copy)
384 continue;
385
386 data = skb_push(skb_copy, NFC_RAW_HEADER_SIZE);
387
388 data[0] = dev ? dev->idx : 0xFF;
389 data[1] = direction & 0x01;
390 data[1] |= (payload_type << 1);
391 }
392
393 nskb = skb_clone(skb_copy, GFP_ATOMIC);
394 if (!nskb)
395 continue;
396
397 if (sock_queue_rcv_skb(sk, nskb))
398 kfree_skb(nskb);
399 }
400
401 read_unlock(&raw_sk_list.lock);
402
403 kfree_skb(skb_copy);
404 }
405 EXPORT_SYMBOL(nfc_send_to_raw_sock);
406
407 static struct proto rawsock_proto = {
408 .name = "NFC_RAW",
409 .owner = THIS_MODULE,
410 .obj_size = sizeof(struct nfc_rawsock),
411 };
412
413 static const struct nfc_protocol rawsock_nfc_proto = {
414 .id = NFC_SOCKPROTO_RAW,
415 .proto = &rawsock_proto,
416 .owner = THIS_MODULE,
417 .create = rawsock_create
418 };
419
420 int __init rawsock_init(void)
421 {
422 int rc;
423
424 rc = nfc_proto_register(&rawsock_nfc_proto);
425
426 return rc;
427 }
428
429 void rawsock_exit(void)
430 {
431 nfc_proto_unregister(&rawsock_nfc_proto);
432 }
433
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.