1 /*
2 RFCOMM implementation for Linux Bluetooth stack (BlueZ).
3 Copyright (C) 2002 Maxim Krasnyansky <maxk@qualcomm.com>
4 Copyright (C) 2002 Marcel Holtmann <marcel@holtmann.org>
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License version 2 as
8 published by the Free Software Foundation;
9
10 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
11 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
12 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
13 IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
14 CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
15 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18
19 ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
20 COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
21 SOFTWARE IS DISCLAIMED.
22 */
23
24 /*
25 * Bluetooth RFCOMM core.
26 */
27
28 #include <linux/module.h>
29 #include <linux/debugfs.h>
30 #include <linux/kthread.h>
31 #include <asm/unaligned.h>
32
33 #include <net/bluetooth/bluetooth.h>
34 #include <net/bluetooth/hci_core.h>
35 #include <net/bluetooth/l2cap.h>
36 #include <net/bluetooth/rfcomm.h>
37
38 #define VERSION "1.11"
39
40 static bool disable_cfc;
41 static bool l2cap_ertm;
42 static int channel_mtu = -1;
43
44 static struct task_struct *rfcomm_thread;
45
46 static DEFINE_MUTEX(rfcomm_mutex);
47 #define rfcomm_lock() mutex_lock(&rfcomm_mutex)
48 #define rfcomm_unlock() mutex_unlock(&rfcomm_mutex)
49
50
51 static LIST_HEAD(session_list);
52
53 static int rfcomm_send_frame(struct rfcomm_session *s, u8 *data, int len);
54 static int rfcomm_send_sabm(struct rfcomm_session *s, u8 dlci);
55 static int rfcomm_send_disc(struct rfcomm_session *s, u8 dlci);
56 static int rfcomm_queue_disc(struct rfcomm_dlc *d);
57 static int rfcomm_send_nsc(struct rfcomm_session *s, int cr, u8 type);
58 static int rfcomm_send_pn(struct rfcomm_session *s, int cr, struct rfcomm_dlc *d);
59 static int rfcomm_send_msc(struct rfcomm_session *s, int cr, u8 dlci, u8 v24_sig);
60 static int rfcomm_send_test(struct rfcomm_session *s, int cr, u8 *pattern, int len);
61 static int rfcomm_send_credits(struct rfcomm_session *s, u8 addr, u8 credits);
62 static void rfcomm_make_uih(struct sk_buff *skb, u8 addr);
63
64 static void rfcomm_process_connect(struct rfcomm_session *s);
65
66 static struct rfcomm_session *rfcomm_session_create(bdaddr_t *src,
67 bdaddr_t *dst,
68 u8 sec_level,
69 int *err);
70 static struct rfcomm_session *rfcomm_session_get(bdaddr_t *src, bdaddr_t *dst);
71 static struct rfcomm_session *rfcomm_session_del(struct rfcomm_session *s);
72
73 /* ---- RFCOMM frame parsing macros ---- */
74 #define __get_dlci(b) ((b & 0xfc) >> 2)
75 #define __get_type(b) ((b & 0xef))
76
77 #define __test_ea(b) ((b & 0x01))
78 #define __test_cr(b) (!!(b & 0x02))
79 #define __test_pf(b) (!!(b & 0x10))
80
81 #define __session_dir(s) ((s)->initiator ? 0x00 : 0x01)
82
83 #define __addr(cr, dlci) (((dlci & 0x3f) << 2) | (cr << 1) | 0x01)
84 #define __ctrl(type, pf) (((type & 0xef) | (pf << 4)))
85 #define __dlci(dir, chn) (((chn & 0x1f) << 1) | dir)
86 #define __srv_channel(dlci) (dlci >> 1)
87
88 #define __len8(len) (((len) << 1) | 1)
89 #define __len16(len) ((len) << 1)
90
91 /* MCC macros */
92 #define __mcc_type(cr, type) (((type << 2) | (cr << 1) | 0x01))
93 #define __get_mcc_type(b) ((b & 0xfc) >> 2)
94 #define __get_mcc_len(b) ((b & 0xfe) >> 1)
95
96 /* RPN macros */
97 #define __rpn_line_settings(data, stop, parity) ((data & 0x3) | ((stop & 0x1) << 2) | ((parity & 0x7) << 3))
98 #define __get_rpn_data_bits(line) ((line) & 0x3)
99 #define __get_rpn_stop_bits(line) (((line) >> 2) & 0x1)
100 #define __get_rpn_parity(line) (((line) >> 3) & 0x7)
101
102 static DECLARE_WAIT_QUEUE_HEAD(rfcomm_wq);
103
rfcomm_schedule(void)104 static void rfcomm_schedule(void)
105 {
106 wake_up_all(&rfcomm_wq);
107 }
108
109 /* ---- RFCOMM FCS computation ---- */
110
111 /* reversed, 8-bit, poly=0x07 */
112 static unsigned char rfcomm_crc_table[256] = {
113 0x00, 0x91, 0xe3, 0x72, 0x07, 0x96, 0xe4, 0x75,
114 0x0e, 0x9f, 0xed, 0x7c, 0x09, 0x98, 0xea, 0x7b,
115 0x1c, 0x8d, 0xff, 0x6e, 0x1b, 0x8a, 0xf8, 0x69,
116 0x12, 0x83, 0xf1, 0x60, 0x15, 0x84, 0xf6, 0x67,
117
118 0x38, 0xa9, 0xdb, 0x4a, 0x3f, 0xae, 0xdc, 0x4d,
119 0x36, 0xa7, 0xd5, 0x44, 0x31, 0xa0, 0xd2, 0x43,
120 0x24, 0xb5, 0xc7, 0x56, 0x23, 0xb2, 0xc0, 0x51,
121 0x2a, 0xbb, 0xc9, 0x58, 0x2d, 0xbc, 0xce, 0x5f,
122
123 0x70, 0xe1, 0x93, 0x02, 0x77, 0xe6, 0x94, 0x05,
124 0x7e, 0xef, 0x9d, 0x0c, 0x79, 0xe8, 0x9a, 0x0b,
125 0x6c, 0xfd, 0x8f, 0x1e, 0x6b, 0xfa, 0x88, 0x19,
126 0x62, 0xf3, 0x81, 0x10, 0x65, 0xf4, 0x86, 0x17,
127
128 0x48, 0xd9, 0xab, 0x3a, 0x4f, 0xde, 0xac, 0x3d,
129 0x46, 0xd7, 0xa5, 0x34, 0x41, 0xd0, 0xa2, 0x33,
130 0x54, 0xc5, 0xb7, 0x26, 0x53, 0xc2, 0xb0, 0x21,
131 0x5a, 0xcb, 0xb9, 0x28, 0x5d, 0xcc, 0xbe, 0x2f,
132
133 0xe0, 0x71, 0x03, 0x92, 0xe7, 0x76, 0x04, 0x95,
134 0xee, 0x7f, 0x0d, 0x9c, 0xe9, 0x78, 0x0a, 0x9b,
135 0xfc, 0x6d, 0x1f, 0x8e, 0xfb, 0x6a, 0x18, 0x89,
136 0xf2, 0x63, 0x11, 0x80, 0xf5, 0x64, 0x16, 0x87,
137
138 0xd8, 0x49, 0x3b, 0xaa, 0xdf, 0x4e, 0x3c, 0xad,
139 0xd6, 0x47, 0x35, 0xa4, 0xd1, 0x40, 0x32, 0xa3,
140 0xc4, 0x55, 0x27, 0xb6, 0xc3, 0x52, 0x20, 0xb1,
141 0xca, 0x5b, 0x29, 0xb8, 0xcd, 0x5c, 0x2e, 0xbf,
142
143 0x90, 0x01, 0x73, 0xe2, 0x97, 0x06, 0x74, 0xe5,
144 0x9e, 0x0f, 0x7d, 0xec, 0x99, 0x08, 0x7a, 0xeb,
145 0x8c, 0x1d, 0x6f, 0xfe, 0x8b, 0x1a, 0x68, 0xf9,
146 0x82, 0x13, 0x61, 0xf0, 0x85, 0x14, 0x66, 0xf7,
147
148 0xa8, 0x39, 0x4b, 0xda, 0xaf, 0x3e, 0x4c, 0xdd,
149 0xa6, 0x37, 0x45, 0xd4, 0xa1, 0x30, 0x42, 0xd3,
150 0xb4, 0x25, 0x57, 0xc6, 0xb3, 0x22, 0x50, 0xc1,
151 0xba, 0x2b, 0x59, 0xc8, 0xbd, 0x2c, 0x5e, 0xcf
152 };
153
154 /* CRC on 2 bytes */
155 #define __crc(data) (rfcomm_crc_table[rfcomm_crc_table[0xff ^ data[0]] ^ data[1]])
156
157 /* FCS on 2 bytes */
__fcs(u8 * data)158 static inline u8 __fcs(u8 *data)
159 {
160 return 0xff - __crc(data);
161 }
162
163 /* FCS on 3 bytes */
__fcs2(u8 * data)164 static inline u8 __fcs2(u8 *data)
165 {
166 return 0xff - rfcomm_crc_table[__crc(data) ^ data[2]];
167 }
168
169 /* Check FCS */
__check_fcs(u8 * data,int type,u8 fcs)170 static inline int __check_fcs(u8 *data, int type, u8 fcs)
171 {
172 u8 f = __crc(data);
173
174 if (type != RFCOMM_UIH)
175 f = rfcomm_crc_table[f ^ data[2]];
176
177 return rfcomm_crc_table[f ^ fcs] != 0xcf;
178 }
179
180 /* ---- L2CAP callbacks ---- */
rfcomm_l2state_change(struct sock * sk)181 static void rfcomm_l2state_change(struct sock *sk)
182 {
183 BT_DBG("%p state %d", sk, sk->sk_state);
184 rfcomm_schedule();
185 }
186
rfcomm_l2data_ready(struct sock * sk)187 static void rfcomm_l2data_ready(struct sock *sk)
188 {
189 BT_DBG("%p", sk);
190 rfcomm_schedule();
191 }
192
rfcomm_l2sock_create(struct socket ** sock)193 static int rfcomm_l2sock_create(struct socket **sock)
194 {
195 int err;
196
197 BT_DBG("");
198
199 err = sock_create_kern(&init_net, PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_L2CAP, sock);
200 if (!err) {
201 struct sock *sk = (*sock)->sk;
202 sk->sk_data_ready = rfcomm_l2data_ready;
203 sk->sk_state_change = rfcomm_l2state_change;
204 }
205 return err;
206 }
207
rfcomm_check_security(struct rfcomm_dlc * d)208 static int rfcomm_check_security(struct rfcomm_dlc *d)
209 {
210 struct sock *sk = d->session->sock->sk;
211 struct l2cap_conn *conn = l2cap_pi(sk)->chan->conn;
212
213 __u8 auth_type;
214
215 switch (d->sec_level) {
216 case BT_SECURITY_HIGH:
217 case BT_SECURITY_FIPS:
218 auth_type = HCI_AT_GENERAL_BONDING_MITM;
219 break;
220 case BT_SECURITY_MEDIUM:
221 auth_type = HCI_AT_GENERAL_BONDING;
222 break;
223 default:
224 auth_type = HCI_AT_NO_BONDING;
225 break;
226 }
227
228 return hci_conn_security(conn->hcon, d->sec_level, auth_type,
229 d->out);
230 }
231
rfcomm_session_timeout(struct timer_list * t)232 static void rfcomm_session_timeout(struct timer_list *t)
233 {
234 struct rfcomm_session *s = from_timer(s, t, timer);
235
236 BT_DBG("session %p state %ld", s, s->state);
237
238 set_bit(RFCOMM_TIMED_OUT, &s->flags);
239 rfcomm_schedule();
240 }
241
rfcomm_session_set_timer(struct rfcomm_session * s,long timeout)242 static void rfcomm_session_set_timer(struct rfcomm_session *s, long timeout)
243 {
244 BT_DBG("session %p state %ld timeout %ld", s, s->state, timeout);
245
246 mod_timer(&s->timer, jiffies + timeout);
247 }
248
rfcomm_session_clear_timer(struct rfcomm_session * s)249 static void rfcomm_session_clear_timer(struct rfcomm_session *s)
250 {
251 BT_DBG("session %p state %ld", s, s->state);
252
253 del_timer_sync(&s->timer);
254 }
255
256 /* ---- RFCOMM DLCs ---- */
rfcomm_dlc_timeout(struct timer_list * t)257 static void rfcomm_dlc_timeout(struct timer_list *t)
258 {
259 struct rfcomm_dlc *d = from_timer(d, t, timer);
260
261 BT_DBG("dlc %p state %ld", d, d->state);
262
263 set_bit(RFCOMM_TIMED_OUT, &d->flags);
264 rfcomm_dlc_put(d);
265 rfcomm_schedule();
266 }
267
rfcomm_dlc_set_timer(struct rfcomm_dlc * d,long timeout)268 static void rfcomm_dlc_set_timer(struct rfcomm_dlc *d, long timeout)
269 {
270 BT_DBG("dlc %p state %ld timeout %ld", d, d->state, timeout);
271
272 if (!mod_timer(&d->timer, jiffies + timeout))
273 rfcomm_dlc_hold(d);
274 }
275
rfcomm_dlc_clear_timer(struct rfcomm_dlc * d)276 static void rfcomm_dlc_clear_timer(struct rfcomm_dlc *d)
277 {
278 BT_DBG("dlc %p state %ld", d, d->state);
279
280 if (del_timer(&d->timer))
281 rfcomm_dlc_put(d);
282 }
283
rfcomm_dlc_clear_state(struct rfcomm_dlc * d)284 static void rfcomm_dlc_clear_state(struct rfcomm_dlc *d)
285 {
286 BT_DBG("%p", d);
287
288 d->state = BT_OPEN;
289 d->flags = 0;
290 d->mscex = 0;
291 d->sec_level = BT_SECURITY_LOW;
292 d->mtu = RFCOMM_DEFAULT_MTU;
293 d->v24_sig = RFCOMM_V24_RTC | RFCOMM_V24_RTR | RFCOMM_V24_DV;
294
295 d->cfc = RFCOMM_CFC_DISABLED;
296 d->rx_credits = RFCOMM_DEFAULT_CREDITS;
297 }
298
rfcomm_dlc_alloc(gfp_t prio)299 struct rfcomm_dlc *rfcomm_dlc_alloc(gfp_t prio)
300 {
301 struct rfcomm_dlc *d = kzalloc(sizeof(*d), prio);
302
303 if (!d)
304 return NULL;
305
306 timer_setup(&d->timer, rfcomm_dlc_timeout, 0);
307
308 skb_queue_head_init(&d->tx_queue);
309 mutex_init(&d->lock);
310 refcount_set(&d->refcnt, 1);
311
312 rfcomm_dlc_clear_state(d);
313
314 BT_DBG("%p", d);
315
316 return d;
317 }
318
rfcomm_dlc_free(struct rfcomm_dlc * d)319 void rfcomm_dlc_free(struct rfcomm_dlc *d)
320 {
321 BT_DBG("%p", d);
322
323 skb_queue_purge(&d->tx_queue);
324 kfree(d);
325 }
326
rfcomm_dlc_link(struct rfcomm_session * s,struct rfcomm_dlc * d)327 static void rfcomm_dlc_link(struct rfcomm_session *s, struct rfcomm_dlc *d)
328 {
329 BT_DBG("dlc %p session %p", d, s);
330
331 rfcomm_session_clear_timer(s);
332 rfcomm_dlc_hold(d);
333 list_add(&d->list, &s->dlcs);
334 d->session = s;
335 }
336
rfcomm_dlc_unlink(struct rfcomm_dlc * d)337 static void rfcomm_dlc_unlink(struct rfcomm_dlc *d)
338 {
339 struct rfcomm_session *s = d->session;
340
341 BT_DBG("dlc %p refcnt %d session %p", d, refcount_read(&d->refcnt), s);
342
343 list_del(&d->list);
344 d->session = NULL;
345 rfcomm_dlc_put(d);
346
347 if (list_empty(&s->dlcs))
348 rfcomm_session_set_timer(s, RFCOMM_IDLE_TIMEOUT);
349 }
350
rfcomm_dlc_get(struct rfcomm_session * s,u8 dlci)351 static struct rfcomm_dlc *rfcomm_dlc_get(struct rfcomm_session *s, u8 dlci)
352 {
353 struct rfcomm_dlc *d;
354
355 list_for_each_entry(d, &s->dlcs, list)
356 if (d->dlci == dlci)
357 return d;
358
359 return NULL;
360 }
361
rfcomm_check_channel(u8 channel)362 static int rfcomm_check_channel(u8 channel)
363 {
364 return channel < 1 || channel > 30;
365 }
366
__rfcomm_dlc_open(struct rfcomm_dlc * d,bdaddr_t * src,bdaddr_t * dst,u8 channel)367 static int __rfcomm_dlc_open(struct rfcomm_dlc *d, bdaddr_t *src, bdaddr_t *dst, u8 channel)
368 {
369 struct rfcomm_session *s;
370 int err = 0;
371 u8 dlci;
372
373 BT_DBG("dlc %p state %ld %pMR -> %pMR channel %d",
374 d, d->state, src, dst, channel);
375
376 if (rfcomm_check_channel(channel))
377 return -EINVAL;
378
379 if (d->state != BT_OPEN && d->state != BT_CLOSED)
380 return 0;
381
382 s = rfcomm_session_get(src, dst);
383 if (!s) {
384 s = rfcomm_session_create(src, dst, d->sec_level, &err);
385 if (!s)
386 return err;
387 }
388
389 dlci = __dlci(__session_dir(s), channel);
390
391 /* Check if DLCI already exists */
392 if (rfcomm_dlc_get(s, dlci))
393 return -EBUSY;
394
395 rfcomm_dlc_clear_state(d);
396
397 d->dlci = dlci;
398 d->addr = __addr(s->initiator, dlci);
399 d->priority = 7;
400
401 d->state = BT_CONFIG;
402 rfcomm_dlc_link(s, d);
403
404 d->out = 1;
405
406 d->mtu = s->mtu;
407 d->cfc = (s->cfc == RFCOMM_CFC_UNKNOWN) ? 0 : s->cfc;
408
409 if (s->state == BT_CONNECTED) {
410 if (rfcomm_check_security(d))
411 rfcomm_send_pn(s, 1, d);
412 else
413 set_bit(RFCOMM_AUTH_PENDING, &d->flags);
414 }
415
416 rfcomm_dlc_set_timer(d, RFCOMM_CONN_TIMEOUT);
417
418 return 0;
419 }
420
rfcomm_dlc_open(struct rfcomm_dlc * d,bdaddr_t * src,bdaddr_t * dst,u8 channel)421 int rfcomm_dlc_open(struct rfcomm_dlc *d, bdaddr_t *src, bdaddr_t *dst, u8 channel)
422 {
423 int r;
424
425 rfcomm_lock();
426
427 r = __rfcomm_dlc_open(d, src, dst, channel);
428
429 rfcomm_unlock();
430 return r;
431 }
432
__rfcomm_dlc_disconn(struct rfcomm_dlc * d)433 static void __rfcomm_dlc_disconn(struct rfcomm_dlc *d)
434 {
435 struct rfcomm_session *s = d->session;
436
437 d->state = BT_DISCONN;
438 if (skb_queue_empty(&d->tx_queue)) {
439 rfcomm_send_disc(s, d->dlci);
440 rfcomm_dlc_set_timer(d, RFCOMM_DISC_TIMEOUT);
441 } else {
442 rfcomm_queue_disc(d);
443 rfcomm_dlc_set_timer(d, RFCOMM_DISC_TIMEOUT * 2);
444 }
445 }
446
__rfcomm_dlc_close(struct rfcomm_dlc * d,int err)447 static int __rfcomm_dlc_close(struct rfcomm_dlc *d, int err)
448 {
449 struct rfcomm_session *s = d->session;
450 if (!s)
451 return 0;
452
453 BT_DBG("dlc %p state %ld dlci %d err %d session %p",
454 d, d->state, d->dlci, err, s);
455
456 switch (d->state) {
457 case BT_CONNECT:
458 case BT_CONFIG:
459 case BT_OPEN:
460 case BT_CONNECT2:
461 if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
462 set_bit(RFCOMM_AUTH_REJECT, &d->flags);
463 rfcomm_schedule();
464 return 0;
465 }
466 }
467
468 switch (d->state) {
469 case BT_CONNECT:
470 case BT_CONNECTED:
471 __rfcomm_dlc_disconn(d);
472 break;
473
474 case BT_CONFIG:
475 if (s->state != BT_BOUND) {
476 __rfcomm_dlc_disconn(d);
477 break;
478 }
479 /* if closing a dlc in a session that hasn't been started,
480 * just close and unlink the dlc
481 */
482 fallthrough;
483
484 default:
485 rfcomm_dlc_clear_timer(d);
486
487 rfcomm_dlc_lock(d);
488 d->state = BT_CLOSED;
489 d->state_change(d, err);
490 rfcomm_dlc_unlock(d);
491
492 skb_queue_purge(&d->tx_queue);
493 rfcomm_dlc_unlink(d);
494 }
495
496 return 0;
497 }
498
rfcomm_dlc_close(struct rfcomm_dlc * d,int err)499 int rfcomm_dlc_close(struct rfcomm_dlc *d, int err)
500 {
501 int r = 0;
502 struct rfcomm_dlc *d_list;
503 struct rfcomm_session *s, *s_list;
504
505 BT_DBG("dlc %p state %ld dlci %d err %d", d, d->state, d->dlci, err);
506
507 rfcomm_lock();
508
509 s = d->session;
510 if (!s)
511 goto no_session;
512
513 /* after waiting on the mutex check the session still exists
514 * then check the dlc still exists
515 */
516 list_for_each_entry(s_list, &session_list, list) {
517 if (s_list == s) {
518 list_for_each_entry(d_list, &s->dlcs, list) {
519 if (d_list == d) {
520 r = __rfcomm_dlc_close(d, err);
521 break;
522 }
523 }
524 break;
525 }
526 }
527
528 no_session:
529 rfcomm_unlock();
530 return r;
531 }
532
rfcomm_dlc_exists(bdaddr_t * src,bdaddr_t * dst,u8 channel)533 struct rfcomm_dlc *rfcomm_dlc_exists(bdaddr_t *src, bdaddr_t *dst, u8 channel)
534 {
535 struct rfcomm_session *s;
536 struct rfcomm_dlc *dlc = NULL;
537 u8 dlci;
538
539 if (rfcomm_check_channel(channel))
540 return ERR_PTR(-EINVAL);
541
542 rfcomm_lock();
543 s = rfcomm_session_get(src, dst);
544 if (s) {
545 dlci = __dlci(__session_dir(s), channel);
546 dlc = rfcomm_dlc_get(s, dlci);
547 }
548 rfcomm_unlock();
549 return dlc;
550 }
551
rfcomm_dlc_send(struct rfcomm_dlc * d,struct sk_buff * skb)552 int rfcomm_dlc_send(struct rfcomm_dlc *d, struct sk_buff *skb)
553 {
554 int len = skb->len;
555
556 if (d->state != BT_CONNECTED)
557 return -ENOTCONN;
558
559 BT_DBG("dlc %p mtu %d len %d", d, d->mtu, len);
560
561 if (len > d->mtu)
562 return -EINVAL;
563
564 rfcomm_make_uih(skb, d->addr);
565 skb_queue_tail(&d->tx_queue, skb);
566
567 if (!test_bit(RFCOMM_TX_THROTTLED, &d->flags))
568 rfcomm_schedule();
569 return len;
570 }
571
rfcomm_dlc_send_noerror(struct rfcomm_dlc * d,struct sk_buff * skb)572 void rfcomm_dlc_send_noerror(struct rfcomm_dlc *d, struct sk_buff *skb)
573 {
574 int len = skb->len;
575
576 BT_DBG("dlc %p mtu %d len %d", d, d->mtu, len);
577
578 rfcomm_make_uih(skb, d->addr);
579 skb_queue_tail(&d->tx_queue, skb);
580
581 if (d->state == BT_CONNECTED &&
582 !test_bit(RFCOMM_TX_THROTTLED, &d->flags))
583 rfcomm_schedule();
584 }
585
__rfcomm_dlc_throttle(struct rfcomm_dlc * d)586 void __rfcomm_dlc_throttle(struct rfcomm_dlc *d)
587 {
588 BT_DBG("dlc %p state %ld", d, d->state);
589
590 if (!d->cfc) {
591 d->v24_sig |= RFCOMM_V24_FC;
592 set_bit(RFCOMM_MSC_PENDING, &d->flags);
593 }
594 rfcomm_schedule();
595 }
596
__rfcomm_dlc_unthrottle(struct rfcomm_dlc * d)597 void __rfcomm_dlc_unthrottle(struct rfcomm_dlc *d)
598 {
599 BT_DBG("dlc %p state %ld", d, d->state);
600
601 if (!d->cfc) {
602 d->v24_sig &= ~RFCOMM_V24_FC;
603 set_bit(RFCOMM_MSC_PENDING, &d->flags);
604 }
605 rfcomm_schedule();
606 }
607
608 /*
609 Set/get modem status functions use _local_ status i.e. what we report
610 to the other side.
611 Remote status is provided by dlc->modem_status() callback.
612 */
rfcomm_dlc_set_modem_status(struct rfcomm_dlc * d,u8 v24_sig)613 int rfcomm_dlc_set_modem_status(struct rfcomm_dlc *d, u8 v24_sig)
614 {
615 BT_DBG("dlc %p state %ld v24_sig 0x%x",
616 d, d->state, v24_sig);
617
618 if (test_bit(RFCOMM_RX_THROTTLED, &d->flags))
619 v24_sig |= RFCOMM_V24_FC;
620 else
621 v24_sig &= ~RFCOMM_V24_FC;
622
623 d->v24_sig = v24_sig;
624
625 if (!test_and_set_bit(RFCOMM_MSC_PENDING, &d->flags))
626 rfcomm_schedule();
627
628 return 0;
629 }
630
rfcomm_dlc_get_modem_status(struct rfcomm_dlc * d,u8 * v24_sig)631 int rfcomm_dlc_get_modem_status(struct rfcomm_dlc *d, u8 *v24_sig)
632 {
633 BT_DBG("dlc %p state %ld v24_sig 0x%x",
634 d, d->state, d->v24_sig);
635
636 *v24_sig = d->v24_sig;
637 return 0;
638 }
639
640 /* ---- RFCOMM sessions ---- */
rfcomm_session_add(struct socket * sock,int state)641 static struct rfcomm_session *rfcomm_session_add(struct socket *sock, int state)
642 {
643 struct rfcomm_session *s = kzalloc(sizeof(*s), GFP_KERNEL);
644
645 if (!s)
646 return NULL;
647
648 BT_DBG("session %p sock %p", s, sock);
649
650 timer_setup(&s->timer, rfcomm_session_timeout, 0);
651
652 INIT_LIST_HEAD(&s->dlcs);
653 s->state = state;
654 s->sock = sock;
655
656 s->mtu = RFCOMM_DEFAULT_MTU;
657 s->cfc = disable_cfc ? RFCOMM_CFC_DISABLED : RFCOMM_CFC_UNKNOWN;
658
659 /* Do not increment module usage count for listening sessions.
660 * Otherwise we won't be able to unload the module. */
661 if (state != BT_LISTEN)
662 if (!try_module_get(THIS_MODULE)) {
663 kfree(s);
664 return NULL;
665 }
666
667 list_add(&s->list, &session_list);
668
669 return s;
670 }
671
rfcomm_session_del(struct rfcomm_session * s)672 static struct rfcomm_session *rfcomm_session_del(struct rfcomm_session *s)
673 {
674 int state = s->state;
675
676 BT_DBG("session %p state %ld", s, s->state);
677
678 list_del(&s->list);
679
680 rfcomm_session_clear_timer(s);
681 sock_release(s->sock);
682 kfree(s);
683
684 if (state != BT_LISTEN)
685 module_put(THIS_MODULE);
686
687 return NULL;
688 }
689
rfcomm_session_get(bdaddr_t * src,bdaddr_t * dst)690 static struct rfcomm_session *rfcomm_session_get(bdaddr_t *src, bdaddr_t *dst)
691 {
692 struct rfcomm_session *s, *n;
693 struct l2cap_chan *chan;
694 list_for_each_entry_safe(s, n, &session_list, list) {
695 chan = l2cap_pi(s->sock->sk)->chan;
696
697 if ((!bacmp(src, BDADDR_ANY) || !bacmp(&chan->src, src)) &&
698 !bacmp(&chan->dst, dst))
699 return s;
700 }
701 return NULL;
702 }
703
rfcomm_session_close(struct rfcomm_session * s,int err)704 static struct rfcomm_session *rfcomm_session_close(struct rfcomm_session *s,
705 int err)
706 {
707 struct rfcomm_dlc *d, *n;
708
709 s->state = BT_CLOSED;
710
711 BT_DBG("session %p state %ld err %d", s, s->state, err);
712
713 /* Close all dlcs */
714 list_for_each_entry_safe(d, n, &s->dlcs, list) {
715 d->state = BT_CLOSED;
716 __rfcomm_dlc_close(d, err);
717 }
718
719 rfcomm_session_clear_timer(s);
720 return rfcomm_session_del(s);
721 }
722
rfcomm_session_create(bdaddr_t * src,bdaddr_t * dst,u8 sec_level,int * err)723 static struct rfcomm_session *rfcomm_session_create(bdaddr_t *src,
724 bdaddr_t *dst,
725 u8 sec_level,
726 int *err)
727 {
728 struct rfcomm_session *s = NULL;
729 struct sockaddr_l2 addr;
730 struct socket *sock;
731 struct sock *sk;
732
733 BT_DBG("%pMR -> %pMR", src, dst);
734
735 *err = rfcomm_l2sock_create(&sock);
736 if (*err < 0)
737 return NULL;
738
739 bacpy(&addr.l2_bdaddr, src);
740 addr.l2_family = AF_BLUETOOTH;
741 addr.l2_psm = 0;
742 addr.l2_cid = 0;
743 addr.l2_bdaddr_type = BDADDR_BREDR;
744 *err = kernel_bind(sock, (struct sockaddr *) &addr, sizeof(addr));
745 if (*err < 0)
746 goto failed;
747
748 /* Set L2CAP options */
749 sk = sock->sk;
750 lock_sock(sk);
751 /* Set MTU to 0 so L2CAP can auto select the MTU */
752 l2cap_pi(sk)->chan->imtu = 0;
753 l2cap_pi(sk)->chan->sec_level = sec_level;
754 if (l2cap_ertm)
755 l2cap_pi(sk)->chan->mode = L2CAP_MODE_ERTM;
756 release_sock(sk);
757
758 s = rfcomm_session_add(sock, BT_BOUND);
759 if (!s) {
760 *err = -ENOMEM;
761 goto failed;
762 }
763
764 s->initiator = 1;
765
766 bacpy(&addr.l2_bdaddr, dst);
767 addr.l2_family = AF_BLUETOOTH;
768 addr.l2_psm = cpu_to_le16(L2CAP_PSM_RFCOMM);
769 addr.l2_cid = 0;
770 addr.l2_bdaddr_type = BDADDR_BREDR;
771 *err = kernel_connect(sock, (struct sockaddr *) &addr, sizeof(addr), O_NONBLOCK);
772 if (*err == 0 || *err == -EINPROGRESS)
773 return s;
774
775 return rfcomm_session_del(s);
776
777 failed:
778 sock_release(sock);
779 return NULL;
780 }
781
rfcomm_session_getaddr(struct rfcomm_session * s,bdaddr_t * src,bdaddr_t * dst)782 void rfcomm_session_getaddr(struct rfcomm_session *s, bdaddr_t *src, bdaddr_t *dst)
783 {
784 struct l2cap_chan *chan = l2cap_pi(s->sock->sk)->chan;
785 if (src)
786 bacpy(src, &chan->src);
787 if (dst)
788 bacpy(dst, &chan->dst);
789 }
790
791 /* ---- RFCOMM frame sending ---- */
rfcomm_send_frame(struct rfcomm_session * s,u8 * data,int len)792 static int rfcomm_send_frame(struct rfcomm_session *s, u8 *data, int len)
793 {
794 struct kvec iv = { data, len };
795 struct msghdr msg;
796
797 BT_DBG("session %p len %d", s, len);
798
799 memset(&msg, 0, sizeof(msg));
800
801 return kernel_sendmsg(s->sock, &msg, &iv, 1, len);
802 }
803
rfcomm_send_cmd(struct rfcomm_session * s,struct rfcomm_cmd * cmd)804 static int rfcomm_send_cmd(struct rfcomm_session *s, struct rfcomm_cmd *cmd)
805 {
806 BT_DBG("%p cmd %u", s, cmd->ctrl);
807
808 return rfcomm_send_frame(s, (void *) cmd, sizeof(*cmd));
809 }
810
rfcomm_send_sabm(struct rfcomm_session * s,u8 dlci)811 static int rfcomm_send_sabm(struct rfcomm_session *s, u8 dlci)
812 {
813 struct rfcomm_cmd cmd;
814
815 BT_DBG("%p dlci %d", s, dlci);
816
817 cmd.addr = __addr(s->initiator, dlci);
818 cmd.ctrl = __ctrl(RFCOMM_SABM, 1);
819 cmd.len = __len8(0);
820 cmd.fcs = __fcs2((u8 *) &cmd);
821
822 return rfcomm_send_cmd(s, &cmd);
823 }
824
rfcomm_send_ua(struct rfcomm_session * s,u8 dlci)825 static int rfcomm_send_ua(struct rfcomm_session *s, u8 dlci)
826 {
827 struct rfcomm_cmd cmd;
828
829 BT_DBG("%p dlci %d", s, dlci);
830
831 cmd.addr = __addr(!s->initiator, dlci);
832 cmd.ctrl = __ctrl(RFCOMM_UA, 1);
833 cmd.len = __len8(0);
834 cmd.fcs = __fcs2((u8 *) &cmd);
835
836 return rfcomm_send_cmd(s, &cmd);
837 }
838
rfcomm_send_disc(struct rfcomm_session * s,u8 dlci)839 static int rfcomm_send_disc(struct rfcomm_session *s, u8 dlci)
840 {
841 struct rfcomm_cmd cmd;
842
843 BT_DBG("%p dlci %d", s, dlci);
844
845 cmd.addr = __addr(s->initiator, dlci);
846 cmd.ctrl = __ctrl(RFCOMM_DISC, 1);
847 cmd.len = __len8(0);
848 cmd.fcs = __fcs2((u8 *) &cmd);
849
850 return rfcomm_send_cmd(s, &cmd);
851 }
852
rfcomm_queue_disc(struct rfcomm_dlc * d)853 static int rfcomm_queue_disc(struct rfcomm_dlc *d)
854 {
855 struct rfcomm_cmd *cmd;
856 struct sk_buff *skb;
857
858 BT_DBG("dlc %p dlci %d", d, d->dlci);
859
860 skb = alloc_skb(sizeof(*cmd), GFP_KERNEL);
861 if (!skb)
862 return -ENOMEM;
863
864 cmd = __skb_put(skb, sizeof(*cmd));
865 cmd->addr = d->addr;
866 cmd->ctrl = __ctrl(RFCOMM_DISC, 1);
867 cmd->len = __len8(0);
868 cmd->fcs = __fcs2((u8 *) cmd);
869
870 skb_queue_tail(&d->tx_queue, skb);
871 rfcomm_schedule();
872 return 0;
873 }
874
rfcomm_send_dm(struct rfcomm_session * s,u8 dlci)875 static int rfcomm_send_dm(struct rfcomm_session *s, u8 dlci)
876 {
877 struct rfcomm_cmd cmd;
878
879 BT_DBG("%p dlci %d", s, dlci);
880
881 cmd.addr = __addr(!s->initiator, dlci);
882 cmd.ctrl = __ctrl(RFCOMM_DM, 1);
883 cmd.len = __len8(0);
884 cmd.fcs = __fcs2((u8 *) &cmd);
885
886 return rfcomm_send_cmd(s, &cmd);
887 }
888
rfcomm_send_nsc(struct rfcomm_session * s,int cr,u8 type)889 static int rfcomm_send_nsc(struct rfcomm_session *s, int cr, u8 type)
890 {
891 struct rfcomm_hdr *hdr;
892 struct rfcomm_mcc *mcc;
893 u8 buf[16], *ptr = buf;
894
895 BT_DBG("%p cr %d type %d", s, cr, type);
896
897 hdr = (void *) ptr; ptr += sizeof(*hdr);
898 hdr->addr = __addr(s->initiator, 0);
899 hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
900 hdr->len = __len8(sizeof(*mcc) + 1);
901
902 mcc = (void *) ptr; ptr += sizeof(*mcc);
903 mcc->type = __mcc_type(0, RFCOMM_NSC);
904 mcc->len = __len8(1);
905
906 /* Type that we didn't like */
907 *ptr = __mcc_type(cr, type); ptr++;
908
909 *ptr = __fcs(buf); ptr++;
910
911 return rfcomm_send_frame(s, buf, ptr - buf);
912 }
913
rfcomm_send_pn(struct rfcomm_session * s,int cr,struct rfcomm_dlc * d)914 static int rfcomm_send_pn(struct rfcomm_session *s, int cr, struct rfcomm_dlc *d)
915 {
916 struct rfcomm_hdr *hdr;
917 struct rfcomm_mcc *mcc;
918 struct rfcomm_pn *pn;
919 u8 buf[16], *ptr = buf;
920
921 BT_DBG("%p cr %d dlci %d mtu %d", s, cr, d->dlci, d->mtu);
922
923 hdr = (void *) ptr; ptr += sizeof(*hdr);
924 hdr->addr = __addr(s->initiator, 0);
925 hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
926 hdr->len = __len8(sizeof(*mcc) + sizeof(*pn));
927
928 mcc = (void *) ptr; ptr += sizeof(*mcc);
929 mcc->type = __mcc_type(cr, RFCOMM_PN);
930 mcc->len = __len8(sizeof(*pn));
931
932 pn = (void *) ptr; ptr += sizeof(*pn);
933 pn->dlci = d->dlci;
934 pn->priority = d->priority;
935 pn->ack_timer = 0;
936 pn->max_retrans = 0;
937
938 if (s->cfc) {
939 pn->flow_ctrl = cr ? 0xf0 : 0xe0;
940 pn->credits = RFCOMM_DEFAULT_CREDITS;
941 } else {
942 pn->flow_ctrl = 0;
943 pn->credits = 0;
944 }
945
946 if (cr && channel_mtu >= 0)
947 pn->mtu = cpu_to_le16(channel_mtu);
948 else
949 pn->mtu = cpu_to_le16(d->mtu);
950
951 *ptr = __fcs(buf); ptr++;
952
953 return rfcomm_send_frame(s, buf, ptr - buf);
954 }
955
rfcomm_send_rpn(struct rfcomm_session * s,int cr,u8 dlci,u8 bit_rate,u8 data_bits,u8 stop_bits,u8 parity,u8 flow_ctrl_settings,u8 xon_char,u8 xoff_char,u16 param_mask)956 int rfcomm_send_rpn(struct rfcomm_session *s, int cr, u8 dlci,
957 u8 bit_rate, u8 data_bits, u8 stop_bits,
958 u8 parity, u8 flow_ctrl_settings,
959 u8 xon_char, u8 xoff_char, u16 param_mask)
960 {
961 struct rfcomm_hdr *hdr;
962 struct rfcomm_mcc *mcc;
963 struct rfcomm_rpn *rpn;
964 u8 buf[16], *ptr = buf;
965
966 BT_DBG("%p cr %d dlci %d bit_r 0x%x data_b 0x%x stop_b 0x%x parity 0x%x"
967 " flwc_s 0x%x xon_c 0x%x xoff_c 0x%x p_mask 0x%x",
968 s, cr, dlci, bit_rate, data_bits, stop_bits, parity,
969 flow_ctrl_settings, xon_char, xoff_char, param_mask);
970
971 hdr = (void *) ptr; ptr += sizeof(*hdr);
972 hdr->addr = __addr(s->initiator, 0);
973 hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
974 hdr->len = __len8(sizeof(*mcc) + sizeof(*rpn));
975
976 mcc = (void *) ptr; ptr += sizeof(*mcc);
977 mcc->type = __mcc_type(cr, RFCOMM_RPN);
978 mcc->len = __len8(sizeof(*rpn));
979
980 rpn = (void *) ptr; ptr += sizeof(*rpn);
981 rpn->dlci = __addr(1, dlci);
982 rpn->bit_rate = bit_rate;
983 rpn->line_settings = __rpn_line_settings(data_bits, stop_bits, parity);
984 rpn->flow_ctrl = flow_ctrl_settings;
985 rpn->xon_char = xon_char;
986 rpn->xoff_char = xoff_char;
987 rpn->param_mask = cpu_to_le16(param_mask);
988
989 *ptr = __fcs(buf); ptr++;
990
991 return rfcomm_send_frame(s, buf, ptr - buf);
992 }
993
rfcomm_send_rls(struct rfcomm_session * s,int cr,u8 dlci,u8 status)994 static int rfcomm_send_rls(struct rfcomm_session *s, int cr, u8 dlci, u8 status)
995 {
996 struct rfcomm_hdr *hdr;
997 struct rfcomm_mcc *mcc;
998 struct rfcomm_rls *rls;
999 u8 buf[16], *ptr = buf;
1000
1001 BT_DBG("%p cr %d status 0x%x", s, cr, status);
1002
1003 hdr = (void *) ptr; ptr += sizeof(*hdr);
1004 hdr->addr = __addr(s->initiator, 0);
1005 hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1006 hdr->len = __len8(sizeof(*mcc) + sizeof(*rls));
1007
1008 mcc = (void *) ptr; ptr += sizeof(*mcc);
1009 mcc->type = __mcc_type(cr, RFCOMM_RLS);
1010 mcc->len = __len8(sizeof(*rls));
1011
1012 rls = (void *) ptr; ptr += sizeof(*rls);
1013 rls->dlci = __addr(1, dlci);
1014 rls->status = status;
1015
1016 *ptr = __fcs(buf); ptr++;
1017
1018 return rfcomm_send_frame(s, buf, ptr - buf);
1019 }
1020
rfcomm_send_msc(struct rfcomm_session * s,int cr,u8 dlci,u8 v24_sig)1021 static int rfcomm_send_msc(struct rfcomm_session *s, int cr, u8 dlci, u8 v24_sig)
1022 {
1023 struct rfcomm_hdr *hdr;
1024 struct rfcomm_mcc *mcc;
1025 struct rfcomm_msc *msc;
1026 u8 buf[16], *ptr = buf;
1027
1028 BT_DBG("%p cr %d v24 0x%x", s, cr, v24_sig);
1029
1030 hdr = (void *) ptr; ptr += sizeof(*hdr);
1031 hdr->addr = __addr(s->initiator, 0);
1032 hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1033 hdr->len = __len8(sizeof(*mcc) + sizeof(*msc));
1034
1035 mcc = (void *) ptr; ptr += sizeof(*mcc);
1036 mcc->type = __mcc_type(cr, RFCOMM_MSC);
1037 mcc->len = __len8(sizeof(*msc));
1038
1039 msc = (void *) ptr; ptr += sizeof(*msc);
1040 msc->dlci = __addr(1, dlci);
1041 msc->v24_sig = v24_sig | 0x01;
1042
1043 *ptr = __fcs(buf); ptr++;
1044
1045 return rfcomm_send_frame(s, buf, ptr - buf);
1046 }
1047
rfcomm_send_fcoff(struct rfcomm_session * s,int cr)1048 static int rfcomm_send_fcoff(struct rfcomm_session *s, int cr)
1049 {
1050 struct rfcomm_hdr *hdr;
1051 struct rfcomm_mcc *mcc;
1052 u8 buf[16], *ptr = buf;
1053
1054 BT_DBG("%p cr %d", s, cr);
1055
1056 hdr = (void *) ptr; ptr += sizeof(*hdr);
1057 hdr->addr = __addr(s->initiator, 0);
1058 hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1059 hdr->len = __len8(sizeof(*mcc));
1060
1061 mcc = (void *) ptr; ptr += sizeof(*mcc);
1062 mcc->type = __mcc_type(cr, RFCOMM_FCOFF);
1063 mcc->len = __len8(0);
1064
1065 *ptr = __fcs(buf); ptr++;
1066
1067 return rfcomm_send_frame(s, buf, ptr - buf);
1068 }
1069
rfcomm_send_fcon(struct rfcomm_session * s,int cr)1070 static int rfcomm_send_fcon(struct rfcomm_session *s, int cr)
1071 {
1072 struct rfcomm_hdr *hdr;
1073 struct rfcomm_mcc *mcc;
1074 u8 buf[16], *ptr = buf;
1075
1076 BT_DBG("%p cr %d", s, cr);
1077
1078 hdr = (void *) ptr; ptr += sizeof(*hdr);
1079 hdr->addr = __addr(s->initiator, 0);
1080 hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1081 hdr->len = __len8(sizeof(*mcc));
1082
1083 mcc = (void *) ptr; ptr += sizeof(*mcc);
1084 mcc->type = __mcc_type(cr, RFCOMM_FCON);
1085 mcc->len = __len8(0);
1086
1087 *ptr = __fcs(buf); ptr++;
1088
1089 return rfcomm_send_frame(s, buf, ptr - buf);
1090 }
1091
rfcomm_send_test(struct rfcomm_session * s,int cr,u8 * pattern,int len)1092 static int rfcomm_send_test(struct rfcomm_session *s, int cr, u8 *pattern, int len)
1093 {
1094 struct socket *sock = s->sock;
1095 struct kvec iv[3];
1096 struct msghdr msg;
1097 unsigned char hdr[5], crc[1];
1098
1099 if (len > 125)
1100 return -EINVAL;
1101
1102 BT_DBG("%p cr %d", s, cr);
1103
1104 hdr[0] = __addr(s->initiator, 0);
1105 hdr[1] = __ctrl(RFCOMM_UIH, 0);
1106 hdr[2] = 0x01 | ((len + 2) << 1);
1107 hdr[3] = 0x01 | ((cr & 0x01) << 1) | (RFCOMM_TEST << 2);
1108 hdr[4] = 0x01 | (len << 1);
1109
1110 crc[0] = __fcs(hdr);
1111
1112 iv[0].iov_base = hdr;
1113 iv[0].iov_len = 5;
1114 iv[1].iov_base = pattern;
1115 iv[1].iov_len = len;
1116 iv[2].iov_base = crc;
1117 iv[2].iov_len = 1;
1118
1119 memset(&msg, 0, sizeof(msg));
1120
1121 return kernel_sendmsg(sock, &msg, iv, 3, 6 + len);
1122 }
1123
rfcomm_send_credits(struct rfcomm_session * s,u8 addr,u8 credits)1124 static int rfcomm_send_credits(struct rfcomm_session *s, u8 addr, u8 credits)
1125 {
1126 struct rfcomm_hdr *hdr;
1127 u8 buf[16], *ptr = buf;
1128
1129 BT_DBG("%p addr %d credits %d", s, addr, credits);
1130
1131 hdr = (void *) ptr; ptr += sizeof(*hdr);
1132 hdr->addr = addr;
1133 hdr->ctrl = __ctrl(RFCOMM_UIH, 1);
1134 hdr->len = __len8(0);
1135
1136 *ptr = credits; ptr++;
1137
1138 *ptr = __fcs(buf); ptr++;
1139
1140 return rfcomm_send_frame(s, buf, ptr - buf);
1141 }
1142
rfcomm_make_uih(struct sk_buff * skb,u8 addr)1143 static void rfcomm_make_uih(struct sk_buff *skb, u8 addr)
1144 {
1145 struct rfcomm_hdr *hdr;
1146 int len = skb->len;
1147 u8 *crc;
1148
1149 if (len > 127) {
1150 hdr = skb_push(skb, 4);
1151 put_unaligned(cpu_to_le16(__len16(len)), (__le16 *) &hdr->len);
1152 } else {
1153 hdr = skb_push(skb, 3);
1154 hdr->len = __len8(len);
1155 }
1156 hdr->addr = addr;
1157 hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1158
1159 crc = skb_put(skb, 1);
1160 *crc = __fcs((void *) hdr);
1161 }
1162
1163 /* ---- RFCOMM frame reception ---- */
rfcomm_recv_ua(struct rfcomm_session * s,u8 dlci)1164 static struct rfcomm_session *rfcomm_recv_ua(struct rfcomm_session *s, u8 dlci)
1165 {
1166 BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1167
1168 if (dlci) {
1169 /* Data channel */
1170 struct rfcomm_dlc *d = rfcomm_dlc_get(s, dlci);
1171 if (!d) {
1172 rfcomm_send_dm(s, dlci);
1173 return s;
1174 }
1175
1176 switch (d->state) {
1177 case BT_CONNECT:
1178 rfcomm_dlc_clear_timer(d);
1179
1180 rfcomm_dlc_lock(d);
1181 d->state = BT_CONNECTED;
1182 d->state_change(d, 0);
1183 rfcomm_dlc_unlock(d);
1184
1185 rfcomm_send_msc(s, 1, dlci, d->v24_sig);
1186 break;
1187
1188 case BT_DISCONN:
1189 d->state = BT_CLOSED;
1190 __rfcomm_dlc_close(d, 0);
1191
1192 if (list_empty(&s->dlcs)) {
1193 s->state = BT_DISCONN;
1194 rfcomm_send_disc(s, 0);
1195 rfcomm_session_clear_timer(s);
1196 }
1197
1198 break;
1199 }
1200 } else {
1201 /* Control channel */
1202 switch (s->state) {
1203 case BT_CONNECT:
1204 s->state = BT_CONNECTED;
1205 rfcomm_process_connect(s);
1206 break;
1207
1208 case BT_DISCONN:
1209 s = rfcomm_session_close(s, ECONNRESET);
1210 break;
1211 }
1212 }
1213 return s;
1214 }
1215
rfcomm_recv_dm(struct rfcomm_session * s,u8 dlci)1216 static struct rfcomm_session *rfcomm_recv_dm(struct rfcomm_session *s, u8 dlci)
1217 {
1218 int err = 0;
1219
1220 BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1221
1222 if (dlci) {
1223 /* Data DLC */
1224 struct rfcomm_dlc *d = rfcomm_dlc_get(s, dlci);
1225 if (d) {
1226 if (d->state == BT_CONNECT || d->state == BT_CONFIG)
1227 err = ECONNREFUSED;
1228 else
1229 err = ECONNRESET;
1230
1231 d->state = BT_CLOSED;
1232 __rfcomm_dlc_close(d, err);
1233 }
1234 } else {
1235 if (s->state == BT_CONNECT)
1236 err = ECONNREFUSED;
1237 else
1238 err = ECONNRESET;
1239
1240 s = rfcomm_session_close(s, err);
1241 }
1242 return s;
1243 }
1244
rfcomm_recv_disc(struct rfcomm_session * s,u8 dlci)1245 static struct rfcomm_session *rfcomm_recv_disc(struct rfcomm_session *s,
1246 u8 dlci)
1247 {
1248 int err = 0;
1249
1250 BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1251
1252 if (dlci) {
1253 struct rfcomm_dlc *d = rfcomm_dlc_get(s, dlci);
1254 if (d) {
1255 rfcomm_send_ua(s, dlci);
1256
1257 if (d->state == BT_CONNECT || d->state == BT_CONFIG)
1258 err = ECONNREFUSED;
1259 else
1260 err = ECONNRESET;
1261
1262 d->state = BT_CLOSED;
1263 __rfcomm_dlc_close(d, err);
1264 } else
1265 rfcomm_send_dm(s, dlci);
1266
1267 } else {
1268 rfcomm_send_ua(s, 0);
1269
1270 if (s->state == BT_CONNECT)
1271 err = ECONNREFUSED;
1272 else
1273 err = ECONNRESET;
1274
1275 s = rfcomm_session_close(s, err);
1276 }
1277 return s;
1278 }
1279
rfcomm_dlc_accept(struct rfcomm_dlc * d)1280 void rfcomm_dlc_accept(struct rfcomm_dlc *d)
1281 {
1282 struct sock *sk = d->session->sock->sk;
1283 struct l2cap_conn *conn = l2cap_pi(sk)->chan->conn;
1284
1285 BT_DBG("dlc %p", d);
1286
1287 rfcomm_send_ua(d->session, d->dlci);
1288
1289 rfcomm_dlc_clear_timer(d);
1290
1291 rfcomm_dlc_lock(d);
1292 d->state = BT_CONNECTED;
1293 d->state_change(d, 0);
1294 rfcomm_dlc_unlock(d);
1295
1296 if (d->role_switch)
1297 hci_conn_switch_role(conn->hcon, 0x00);
1298
1299 rfcomm_send_msc(d->session, 1, d->dlci, d->v24_sig);
1300 }
1301
rfcomm_check_accept(struct rfcomm_dlc * d)1302 static void rfcomm_check_accept(struct rfcomm_dlc *d)
1303 {
1304 if (rfcomm_check_security(d)) {
1305 if (d->defer_setup) {
1306 set_bit(RFCOMM_DEFER_SETUP, &d->flags);
1307 rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1308
1309 rfcomm_dlc_lock(d);
1310 d->state = BT_CONNECT2;
1311 d->state_change(d, 0);
1312 rfcomm_dlc_unlock(d);
1313 } else
1314 rfcomm_dlc_accept(d);
1315 } else {
1316 set_bit(RFCOMM_AUTH_PENDING, &d->flags);
1317 rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1318 }
1319 }
1320
rfcomm_recv_sabm(struct rfcomm_session * s,u8 dlci)1321 static int rfcomm_recv_sabm(struct rfcomm_session *s, u8 dlci)
1322 {
1323 struct rfcomm_dlc *d;
1324 u8 channel;
1325
1326 BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1327
1328 if (!dlci) {
1329 rfcomm_send_ua(s, 0);
1330
1331 if (s->state == BT_OPEN) {
1332 s->state = BT_CONNECTED;
1333 rfcomm_process_connect(s);
1334 }
1335 return 0;
1336 }
1337
1338 /* Check if DLC exists */
1339 d = rfcomm_dlc_get(s, dlci);
1340 if (d) {
1341 if (d->state == BT_OPEN) {
1342 /* DLC was previously opened by PN request */
1343 rfcomm_check_accept(d);
1344 }
1345 return 0;
1346 }
1347
1348 /* Notify socket layer about incoming connection */
1349 channel = __srv_channel(dlci);
1350 if (rfcomm_connect_ind(s, channel, &d)) {
1351 d->dlci = dlci;
1352 d->addr = __addr(s->initiator, dlci);
1353 rfcomm_dlc_link(s, d);
1354
1355 rfcomm_check_accept(d);
1356 } else {
1357 rfcomm_send_dm(s, dlci);
1358 }
1359
1360 return 0;
1361 }
1362
rfcomm_apply_pn(struct rfcomm_dlc * d,int cr,struct rfcomm_pn * pn)1363 static int rfcomm_apply_pn(struct rfcomm_dlc *d, int cr, struct rfcomm_pn *pn)
1364 {
1365 struct rfcomm_session *s = d->session;
1366
1367 BT_DBG("dlc %p state %ld dlci %d mtu %d fc 0x%x credits %d",
1368 d, d->state, d->dlci, pn->mtu, pn->flow_ctrl, pn->credits);
1369
1370 if ((pn->flow_ctrl == 0xf0 && s->cfc != RFCOMM_CFC_DISABLED) ||
1371 pn->flow_ctrl == 0xe0) {
1372 d->cfc = RFCOMM_CFC_ENABLED;
1373 d->tx_credits = pn->credits;
1374 } else {
1375 d->cfc = RFCOMM_CFC_DISABLED;
1376 set_bit(RFCOMM_TX_THROTTLED, &d->flags);
1377 }
1378
1379 if (s->cfc == RFCOMM_CFC_UNKNOWN)
1380 s->cfc = d->cfc;
1381
1382 d->priority = pn->priority;
1383
1384 d->mtu = __le16_to_cpu(pn->mtu);
1385
1386 if (cr && d->mtu > s->mtu)
1387 d->mtu = s->mtu;
1388
1389 return 0;
1390 }
1391
rfcomm_recv_pn(struct rfcomm_session * s,int cr,struct sk_buff * skb)1392 static int rfcomm_recv_pn(struct rfcomm_session *s, int cr, struct sk_buff *skb)
1393 {
1394 struct rfcomm_pn *pn = (void *) skb->data;
1395 struct rfcomm_dlc *d;
1396 u8 dlci = pn->dlci;
1397
1398 BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1399
1400 if (!dlci)
1401 return 0;
1402
1403 d = rfcomm_dlc_get(s, dlci);
1404 if (d) {
1405 if (cr) {
1406 /* PN request */
1407 rfcomm_apply_pn(d, cr, pn);
1408 rfcomm_send_pn(s, 0, d);
1409 } else {
1410 /* PN response */
1411 switch (d->state) {
1412 case BT_CONFIG:
1413 rfcomm_apply_pn(d, cr, pn);
1414
1415 d->state = BT_CONNECT;
1416 rfcomm_send_sabm(s, d->dlci);
1417 break;
1418 }
1419 }
1420 } else {
1421 u8 channel = __srv_channel(dlci);
1422
1423 if (!cr)
1424 return 0;
1425
1426 /* PN request for non existing DLC.
1427 * Assume incoming connection. */
1428 if (rfcomm_connect_ind(s, channel, &d)) {
1429 d->dlci = dlci;
1430 d->addr = __addr(s->initiator, dlci);
1431 rfcomm_dlc_link(s, d);
1432
1433 rfcomm_apply_pn(d, cr, pn);
1434
1435 d->state = BT_OPEN;
1436 rfcomm_send_pn(s, 0, d);
1437 } else {
1438 rfcomm_send_dm(s, dlci);
1439 }
1440 }
1441 return 0;
1442 }
1443
rfcomm_recv_rpn(struct rfcomm_session * s,int cr,int len,struct sk_buff * skb)1444 static int rfcomm_recv_rpn(struct rfcomm_session *s, int cr, int len, struct sk_buff *skb)
1445 {
1446 struct rfcomm_rpn *rpn = (void *) skb->data;
1447 u8 dlci = __get_dlci(rpn->dlci);
1448
1449 u8 bit_rate = 0;
1450 u8 data_bits = 0;
1451 u8 stop_bits = 0;
1452 u8 parity = 0;
1453 u8 flow_ctrl = 0;
1454 u8 xon_char = 0;
1455 u8 xoff_char = 0;
1456 u16 rpn_mask = RFCOMM_RPN_PM_ALL;
1457
1458 BT_DBG("dlci %d cr %d len 0x%x bitr 0x%x line 0x%x flow 0x%x xonc 0x%x xoffc 0x%x pm 0x%x",
1459 dlci, cr, len, rpn->bit_rate, rpn->line_settings, rpn->flow_ctrl,
1460 rpn->xon_char, rpn->xoff_char, rpn->param_mask);
1461
1462 if (!cr)
1463 return 0;
1464
1465 if (len == 1) {
1466 /* This is a request, return default (according to ETSI TS 07.10) settings */
1467 bit_rate = RFCOMM_RPN_BR_9600;
1468 data_bits = RFCOMM_RPN_DATA_8;
1469 stop_bits = RFCOMM_RPN_STOP_1;
1470 parity = RFCOMM_RPN_PARITY_NONE;
1471 flow_ctrl = RFCOMM_RPN_FLOW_NONE;
1472 xon_char = RFCOMM_RPN_XON_CHAR;
1473 xoff_char = RFCOMM_RPN_XOFF_CHAR;
1474 goto rpn_out;
1475 }
1476
1477 /* Check for sane values, ignore/accept bit_rate, 8 bits, 1 stop bit,
1478 * no parity, no flow control lines, normal XON/XOFF chars */
1479
1480 if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_BITRATE)) {
1481 bit_rate = rpn->bit_rate;
1482 if (bit_rate > RFCOMM_RPN_BR_230400) {
1483 BT_DBG("RPN bit rate mismatch 0x%x", bit_rate);
1484 bit_rate = RFCOMM_RPN_BR_9600;
1485 rpn_mask ^= RFCOMM_RPN_PM_BITRATE;
1486 }
1487 }
1488
1489 if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_DATA)) {
1490 data_bits = __get_rpn_data_bits(rpn->line_settings);
1491 if (data_bits != RFCOMM_RPN_DATA_8) {
1492 BT_DBG("RPN data bits mismatch 0x%x", data_bits);
1493 data_bits = RFCOMM_RPN_DATA_8;
1494 rpn_mask ^= RFCOMM_RPN_PM_DATA;
1495 }
1496 }
1497
1498 if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_STOP)) {
1499 stop_bits = __get_rpn_stop_bits(rpn->line_settings);
1500 if (stop_bits != RFCOMM_RPN_STOP_1) {
1501 BT_DBG("RPN stop bits mismatch 0x%x", stop_bits);
1502 stop_bits = RFCOMM_RPN_STOP_1;
1503 rpn_mask ^= RFCOMM_RPN_PM_STOP;
1504 }
1505 }
1506
1507 if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_PARITY)) {
1508 parity = __get_rpn_parity(rpn->line_settings);
1509 if (parity != RFCOMM_RPN_PARITY_NONE) {
1510 BT_DBG("RPN parity mismatch 0x%x", parity);
1511 parity = RFCOMM_RPN_PARITY_NONE;
1512 rpn_mask ^= RFCOMM_RPN_PM_PARITY;
1513 }
1514 }
1515
1516 if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_FLOW)) {
1517 flow_ctrl = rpn->flow_ctrl;
1518 if (flow_ctrl != RFCOMM_RPN_FLOW_NONE) {
1519 BT_DBG("RPN flow ctrl mismatch 0x%x", flow_ctrl);
1520 flow_ctrl = RFCOMM_RPN_FLOW_NONE;
1521 rpn_mask ^= RFCOMM_RPN_PM_FLOW;
1522 }
1523 }
1524
1525 if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_XON)) {
1526 xon_char = rpn->xon_char;
1527 if (xon_char != RFCOMM_RPN_XON_CHAR) {
1528 BT_DBG("RPN XON char mismatch 0x%x", xon_char);
1529 xon_char = RFCOMM_RPN_XON_CHAR;
1530 rpn_mask ^= RFCOMM_RPN_PM_XON;
1531 }
1532 }
1533
1534 if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_XOFF)) {
1535 xoff_char = rpn->xoff_char;
1536 if (xoff_char != RFCOMM_RPN_XOFF_CHAR) {
1537 BT_DBG("RPN XOFF char mismatch 0x%x", xoff_char);
1538 xoff_char = RFCOMM_RPN_XOFF_CHAR;
1539 rpn_mask ^= RFCOMM_RPN_PM_XOFF;
1540 }
1541 }
1542
1543 rpn_out:
1544 rfcomm_send_rpn(s, 0, dlci, bit_rate, data_bits, stop_bits,
1545 parity, flow_ctrl, xon_char, xoff_char, rpn_mask);
1546
1547 return 0;
1548 }
1549
rfcomm_recv_rls(struct rfcomm_session * s,int cr,struct sk_buff * skb)1550 static int rfcomm_recv_rls(struct rfcomm_session *s, int cr, struct sk_buff *skb)
1551 {
1552 struct rfcomm_rls *rls = (void *) skb->data;
1553 u8 dlci = __get_dlci(rls->dlci);
1554
1555 BT_DBG("dlci %d cr %d status 0x%x", dlci, cr, rls->status);
1556
1557 if (!cr)
1558 return 0;
1559
1560 /* We should probably do something with this information here. But
1561 * for now it's sufficient just to reply -- Bluetooth 1.1 says it's
1562 * mandatory to recognise and respond to RLS */
1563
1564 rfcomm_send_rls(s, 0, dlci, rls->status);
1565
1566 return 0;
1567 }
1568
rfcomm_recv_msc(struct rfcomm_session * s,int cr,struct sk_buff * skb)1569 static int rfcomm_recv_msc(struct rfcomm_session *s, int cr, struct sk_buff *skb)
1570 {
1571 struct rfcomm_msc *msc = (void *) skb->data;
1572 struct rfcomm_dlc *d;
1573 u8 dlci = __get_dlci(msc->dlci);
1574
1575 BT_DBG("dlci %d cr %d v24 0x%x", dlci, cr, msc->v24_sig);
1576
1577 d = rfcomm_dlc_get(s, dlci);
1578 if (!d)
1579 return 0;
1580
1581 if (cr) {
1582 if (msc->v24_sig & RFCOMM_V24_FC && !d->cfc)
1583 set_bit(RFCOMM_TX_THROTTLED, &d->flags);
1584 else
1585 clear_bit(RFCOMM_TX_THROTTLED, &d->flags);
1586
1587 rfcomm_dlc_lock(d);
1588
1589 d->remote_v24_sig = msc->v24_sig;
1590
1591 if (d->modem_status)
1592 d->modem_status(d, msc->v24_sig);
1593
1594 rfcomm_dlc_unlock(d);
1595
1596 rfcomm_send_msc(s, 0, dlci, msc->v24_sig);
1597
1598 d->mscex |= RFCOMM_MSCEX_RX;
1599 } else
1600 d->mscex |= RFCOMM_MSCEX_TX;
1601
1602 return 0;
1603 }
1604
rfcomm_recv_mcc(struct rfcomm_session * s,struct sk_buff * skb)1605 static int rfcomm_recv_mcc(struct rfcomm_session *s, struct sk_buff *skb)
1606 {
1607 struct rfcomm_mcc *mcc = (void *) skb->data;
1608 u8 type, cr, len;
1609
1610 cr = __test_cr(mcc->type);
1611 type = __get_mcc_type(mcc->type);
1612 len = __get_mcc_len(mcc->len);
1613
1614 BT_DBG("%p type 0x%x cr %d", s, type, cr);
1615
1616 skb_pull(skb, 2);
1617
1618 switch (type) {
1619 case RFCOMM_PN:
1620 rfcomm_recv_pn(s, cr, skb);
1621 break;
1622
1623 case RFCOMM_RPN:
1624 rfcomm_recv_rpn(s, cr, len, skb);
1625 break;
1626
1627 case RFCOMM_RLS:
1628 rfcomm_recv_rls(s, cr, skb);
1629 break;
1630
1631 case RFCOMM_MSC:
1632 rfcomm_recv_msc(s, cr, skb);
1633 break;
1634
1635 case RFCOMM_FCOFF:
1636 if (cr) {
1637 set_bit(RFCOMM_TX_THROTTLED, &s->flags);
1638 rfcomm_send_fcoff(s, 0);
1639 }
1640 break;
1641
1642 case RFCOMM_FCON:
1643 if (cr) {
1644 clear_bit(RFCOMM_TX_THROTTLED, &s->flags);
1645 rfcomm_send_fcon(s, 0);
1646 }
1647 break;
1648
1649 case RFCOMM_TEST:
1650 if (cr)
1651 rfcomm_send_test(s, 0, skb->data, skb->len);
1652 break;
1653
1654 case RFCOMM_NSC:
1655 break;
1656
1657 default:
1658 BT_ERR("Unknown control type 0x%02x", type);
1659 rfcomm_send_nsc(s, cr, type);
1660 break;
1661 }
1662 return 0;
1663 }
1664
rfcomm_recv_data(struct rfcomm_session * s,u8 dlci,int pf,struct sk_buff * skb)1665 static int rfcomm_recv_data(struct rfcomm_session *s, u8 dlci, int pf, struct sk_buff *skb)
1666 {
1667 struct rfcomm_dlc *d;
1668
1669 BT_DBG("session %p state %ld dlci %d pf %d", s, s->state, dlci, pf);
1670
1671 d = rfcomm_dlc_get(s, dlci);
1672 if (!d) {
1673 rfcomm_send_dm(s, dlci);
1674 goto drop;
1675 }
1676
1677 if (pf && d->cfc) {
1678 u8 credits = *(u8 *) skb->data; skb_pull(skb, 1);
1679
1680 d->tx_credits += credits;
1681 if (d->tx_credits)
1682 clear_bit(RFCOMM_TX_THROTTLED, &d->flags);
1683 }
1684
1685 if (skb->len && d->state == BT_CONNECTED) {
1686 rfcomm_dlc_lock(d);
1687 d->rx_credits--;
1688 d->data_ready(d, skb);
1689 rfcomm_dlc_unlock(d);
1690 return 0;
1691 }
1692
1693 drop:
1694 kfree_skb(skb);
1695 return 0;
1696 }
1697
rfcomm_recv_frame(struct rfcomm_session * s,struct sk_buff * skb)1698 static struct rfcomm_session *rfcomm_recv_frame(struct rfcomm_session *s,
1699 struct sk_buff *skb)
1700 {
1701 struct rfcomm_hdr *hdr = (void *) skb->data;
1702 u8 type, dlci, fcs;
1703
1704 if (!s) {
1705 /* no session, so free socket data */
1706 kfree_skb(skb);
1707 return s;
1708 }
1709
1710 dlci = __get_dlci(hdr->addr);
1711 type = __get_type(hdr->ctrl);
1712
1713 /* Trim FCS */
1714 skb->len--; skb->tail--;
1715 fcs = *(u8 *)skb_tail_pointer(skb);
1716
1717 if (__check_fcs(skb->data, type, fcs)) {
1718 BT_ERR("bad checksum in packet");
1719 kfree_skb(skb);
1720 return s;
1721 }
1722
1723 if (__test_ea(hdr->len))
1724 skb_pull(skb, 3);
1725 else
1726 skb_pull(skb, 4);
1727
1728 switch (type) {
1729 case RFCOMM_SABM:
1730 if (__test_pf(hdr->ctrl))
1731 rfcomm_recv_sabm(s, dlci);
1732 break;
1733
1734 case RFCOMM_DISC:
1735 if (__test_pf(hdr->ctrl))
1736 s = rfcomm_recv_disc(s, dlci);
1737 break;
1738
1739 case RFCOMM_UA:
1740 if (__test_pf(hdr->ctrl))
1741 s = rfcomm_recv_ua(s, dlci);
1742 break;
1743
1744 case RFCOMM_DM:
1745 s = rfcomm_recv_dm(s, dlci);
1746 break;
1747
1748 case RFCOMM_UIH:
1749 if (dlci) {
1750 rfcomm_recv_data(s, dlci, __test_pf(hdr->ctrl), skb);
1751 return s;
1752 }
1753 rfcomm_recv_mcc(s, skb);
1754 break;
1755
1756 default:
1757 BT_ERR("Unknown packet type 0x%02x", type);
1758 break;
1759 }
1760 kfree_skb(skb);
1761 return s;
1762 }
1763
1764 /* ---- Connection and data processing ---- */
1765
rfcomm_process_connect(struct rfcomm_session * s)1766 static void rfcomm_process_connect(struct rfcomm_session *s)
1767 {
1768 struct rfcomm_dlc *d, *n;
1769
1770 BT_DBG("session %p state %ld", s, s->state);
1771
1772 list_for_each_entry_safe(d, n, &s->dlcs, list) {
1773 if (d->state == BT_CONFIG) {
1774 d->mtu = s->mtu;
1775 if (rfcomm_check_security(d)) {
1776 rfcomm_send_pn(s, 1, d);
1777 } else {
1778 set_bit(RFCOMM_AUTH_PENDING, &d->flags);
1779 rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1780 }
1781 }
1782 }
1783 }
1784
1785 /* Send data queued for the DLC.
1786 * Return number of frames left in the queue.
1787 */
rfcomm_process_tx(struct rfcomm_dlc * d)1788 static int rfcomm_process_tx(struct rfcomm_dlc *d)
1789 {
1790 struct sk_buff *skb;
1791 int err;
1792
1793 BT_DBG("dlc %p state %ld cfc %d rx_credits %d tx_credits %d",
1794 d, d->state, d->cfc, d->rx_credits, d->tx_credits);
1795
1796 /* Send pending MSC */
1797 if (test_and_clear_bit(RFCOMM_MSC_PENDING, &d->flags))
1798 rfcomm_send_msc(d->session, 1, d->dlci, d->v24_sig);
1799
1800 if (d->cfc) {
1801 /* CFC enabled.
1802 * Give them some credits */
1803 if (!test_bit(RFCOMM_RX_THROTTLED, &d->flags) &&
1804 d->rx_credits <= (d->cfc >> 2)) {
1805 rfcomm_send_credits(d->session, d->addr, d->cfc - d->rx_credits);
1806 d->rx_credits = d->cfc;
1807 }
1808 } else {
1809 /* CFC disabled.
1810 * Give ourselves some credits */
1811 d->tx_credits = 5;
1812 }
1813
1814 if (test_bit(RFCOMM_TX_THROTTLED, &d->flags))
1815 return skb_queue_len(&d->tx_queue);
1816
1817 while (d->tx_credits && (skb = skb_dequeue(&d->tx_queue))) {
1818 err = rfcomm_send_frame(d->session, skb->data, skb->len);
1819 if (err < 0) {
1820 skb_queue_head(&d->tx_queue, skb);
1821 break;
1822 }
1823 kfree_skb(skb);
1824 d->tx_credits--;
1825 }
1826
1827 if (d->cfc && !d->tx_credits) {
1828 /* We're out of TX credits.
1829 * Set TX_THROTTLED flag to avoid unnesary wakeups by dlc_send. */
1830 set_bit(RFCOMM_TX_THROTTLED, &d->flags);
1831 }
1832
1833 return skb_queue_len(&d->tx_queue);
1834 }
1835
rfcomm_process_dlcs(struct rfcomm_session * s)1836 static void rfcomm_process_dlcs(struct rfcomm_session *s)
1837 {
1838 struct rfcomm_dlc *d, *n;
1839
1840 BT_DBG("session %p state %ld", s, s->state);
1841
1842 list_for_each_entry_safe(d, n, &s->dlcs, list) {
1843 if (test_bit(RFCOMM_TIMED_OUT, &d->flags)) {
1844 __rfcomm_dlc_close(d, ETIMEDOUT);
1845 continue;
1846 }
1847
1848 if (test_bit(RFCOMM_ENC_DROP, &d->flags)) {
1849 __rfcomm_dlc_close(d, ECONNREFUSED);
1850 continue;
1851 }
1852
1853 if (test_and_clear_bit(RFCOMM_AUTH_ACCEPT, &d->flags)) {
1854 rfcomm_dlc_clear_timer(d);
1855 if (d->out) {
1856 rfcomm_send_pn(s, 1, d);
1857 rfcomm_dlc_set_timer(d, RFCOMM_CONN_TIMEOUT);
1858 } else {
1859 if (d->defer_setup) {
1860 set_bit(RFCOMM_DEFER_SETUP, &d->flags);
1861 rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1862
1863 rfcomm_dlc_lock(d);
1864 d->state = BT_CONNECT2;
1865 d->state_change(d, 0);
1866 rfcomm_dlc_unlock(d);
1867 } else
1868 rfcomm_dlc_accept(d);
1869 }
1870 continue;
1871 } else if (test_and_clear_bit(RFCOMM_AUTH_REJECT, &d->flags)) {
1872 rfcomm_dlc_clear_timer(d);
1873 if (!d->out)
1874 rfcomm_send_dm(s, d->dlci);
1875 else
1876 d->state = BT_CLOSED;
1877 __rfcomm_dlc_close(d, ECONNREFUSED);
1878 continue;
1879 }
1880
1881 if (test_bit(RFCOMM_SEC_PENDING, &d->flags))
1882 continue;
1883
1884 if (test_bit(RFCOMM_TX_THROTTLED, &s->flags))
1885 continue;
1886
1887 if ((d->state == BT_CONNECTED || d->state == BT_DISCONN) &&
1888 d->mscex == RFCOMM_MSCEX_OK)
1889 rfcomm_process_tx(d);
1890 }
1891 }
1892
rfcomm_process_rx(struct rfcomm_session * s)1893 static struct rfcomm_session *rfcomm_process_rx(struct rfcomm_session *s)
1894 {
1895 struct socket *sock = s->sock;
1896 struct sock *sk = sock->sk;
1897 struct sk_buff *skb;
1898
1899 BT_DBG("session %p state %ld qlen %d", s, s->state, skb_queue_len(&sk->sk_receive_queue));
1900
1901 /* Get data directly from socket receive queue without copying it. */
1902 while ((skb = skb_dequeue(&sk->sk_receive_queue))) {
1903 skb_orphan(skb);
1904 if (!skb_linearize(skb)) {
1905 s = rfcomm_recv_frame(s, skb);
1906 if (!s)
1907 break;
1908 } else {
1909 kfree_skb(skb);
1910 }
1911 }
1912
1913 if (s && (sk->sk_state == BT_CLOSED))
1914 s = rfcomm_session_close(s, sk->sk_err);
1915
1916 return s;
1917 }
1918
rfcomm_accept_connection(struct rfcomm_session * s)1919 static void rfcomm_accept_connection(struct rfcomm_session *s)
1920 {
1921 struct socket *sock = s->sock, *nsock;
1922 int err;
1923
1924 /* Fast check for a new connection.
1925 * Avoids unnesesary socket allocations. */
1926 if (list_empty(&bt_sk(sock->sk)->accept_q))
1927 return;
1928
1929 BT_DBG("session %p", s);
1930
1931 err = kernel_accept(sock, &nsock, O_NONBLOCK);
1932 if (err < 0)
1933 return;
1934
1935 /* Set our callbacks */
1936 nsock->sk->sk_data_ready = rfcomm_l2data_ready;
1937 nsock->sk->sk_state_change = rfcomm_l2state_change;
1938
1939 s = rfcomm_session_add(nsock, BT_OPEN);
1940 if (s) {
1941 /* We should adjust MTU on incoming sessions.
1942 * L2CAP MTU minus UIH header and FCS. */
1943 s->mtu = min(l2cap_pi(nsock->sk)->chan->omtu,
1944 l2cap_pi(nsock->sk)->chan->imtu) - 5;
1945
1946 rfcomm_schedule();
1947 } else
1948 sock_release(nsock);
1949 }
1950
rfcomm_check_connection(struct rfcomm_session * s)1951 static struct rfcomm_session *rfcomm_check_connection(struct rfcomm_session *s)
1952 {
1953 struct sock *sk = s->sock->sk;
1954
1955 BT_DBG("%p state %ld", s, s->state);
1956
1957 switch (sk->sk_state) {
1958 case BT_CONNECTED:
1959 s->state = BT_CONNECT;
1960
1961 /* We can adjust MTU on outgoing sessions.
1962 * L2CAP MTU minus UIH header and FCS. */
1963 s->mtu = min(l2cap_pi(sk)->chan->omtu, l2cap_pi(sk)->chan->imtu) - 5;
1964
1965 rfcomm_send_sabm(s, 0);
1966 break;
1967
1968 case BT_CLOSED:
1969 s = rfcomm_session_close(s, sk->sk_err);
1970 break;
1971 }
1972 return s;
1973 }
1974
rfcomm_process_sessions(void)1975 static void rfcomm_process_sessions(void)
1976 {
1977 struct rfcomm_session *s, *n;
1978
1979 rfcomm_lock();
1980
1981 list_for_each_entry_safe(s, n, &session_list, list) {
1982 if (test_and_clear_bit(RFCOMM_TIMED_OUT, &s->flags)) {
1983 s->state = BT_DISCONN;
1984 rfcomm_send_disc(s, 0);
1985 continue;
1986 }
1987
1988 switch (s->state) {
1989 case BT_LISTEN:
1990 rfcomm_accept_connection(s);
1991 continue;
1992
1993 case BT_BOUND:
1994 s = rfcomm_check_connection(s);
1995 break;
1996
1997 default:
1998 s = rfcomm_process_rx(s);
1999 break;
2000 }
2001
2002 if (s)
2003 rfcomm_process_dlcs(s);
2004 }
2005
2006 rfcomm_unlock();
2007 }
2008
rfcomm_add_listener(bdaddr_t * ba)2009 static int rfcomm_add_listener(bdaddr_t *ba)
2010 {
2011 struct sockaddr_l2 addr;
2012 struct socket *sock;
2013 struct sock *sk;
2014 struct rfcomm_session *s;
2015 int err = 0;
2016
2017 /* Create socket */
2018 err = rfcomm_l2sock_create(&sock);
2019 if (err < 0) {
2020 BT_ERR("Create socket failed %d", err);
2021 return err;
2022 }
2023
2024 /* Bind socket */
2025 bacpy(&addr.l2_bdaddr, ba);
2026 addr.l2_family = AF_BLUETOOTH;
2027 addr.l2_psm = cpu_to_le16(L2CAP_PSM_RFCOMM);
2028 addr.l2_cid = 0;
2029 addr.l2_bdaddr_type = BDADDR_BREDR;
2030 err = kernel_bind(sock, (struct sockaddr *) &addr, sizeof(addr));
2031 if (err < 0) {
2032 BT_ERR("Bind failed %d", err);
2033 goto failed;
2034 }
2035
2036 /* Set L2CAP options */
2037 sk = sock->sk;
2038 lock_sock(sk);
2039 /* Set MTU to 0 so L2CAP can auto select the MTU */
2040 l2cap_pi(sk)->chan->imtu = 0;
2041 release_sock(sk);
2042
2043 /* Start listening on the socket */
2044 err = kernel_listen(sock, 10);
2045 if (err) {
2046 BT_ERR("Listen failed %d", err);
2047 goto failed;
2048 }
2049
2050 /* Add listening session */
2051 s = rfcomm_session_add(sock, BT_LISTEN);
2052 if (!s) {
2053 err = -ENOMEM;
2054 goto failed;
2055 }
2056
2057 return 0;
2058 failed:
2059 sock_release(sock);
2060 return err;
2061 }
2062
rfcomm_kill_listener(void)2063 static void rfcomm_kill_listener(void)
2064 {
2065 struct rfcomm_session *s, *n;
2066
2067 BT_DBG("");
2068
2069 list_for_each_entry_safe(s, n, &session_list, list)
2070 rfcomm_session_del(s);
2071 }
2072
rfcomm_run(void * unused)2073 static int rfcomm_run(void *unused)
2074 {
2075 DEFINE_WAIT_FUNC(wait, woken_wake_function);
2076 BT_DBG("");
2077
2078 set_user_nice(current, -10);
2079
2080 rfcomm_add_listener(BDADDR_ANY);
2081
2082 add_wait_queue(&rfcomm_wq, &wait);
2083 while (!kthread_should_stop()) {
2084
2085 /* Process stuff */
2086 rfcomm_process_sessions();
2087
2088 wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
2089 }
2090 remove_wait_queue(&rfcomm_wq, &wait);
2091
2092 rfcomm_kill_listener();
2093
2094 return 0;
2095 }
2096
rfcomm_security_cfm(struct hci_conn * conn,u8 status,u8 encrypt)2097 static void rfcomm_security_cfm(struct hci_conn *conn, u8 status, u8 encrypt)
2098 {
2099 struct rfcomm_session *s;
2100 struct rfcomm_dlc *d, *n;
2101
2102 BT_DBG("conn %p status 0x%02x encrypt 0x%02x", conn, status, encrypt);
2103
2104 s = rfcomm_session_get(&conn->hdev->bdaddr, &conn->dst);
2105 if (!s)
2106 return;
2107
2108 list_for_each_entry_safe(d, n, &s->dlcs, list) {
2109 if (test_and_clear_bit(RFCOMM_SEC_PENDING, &d->flags)) {
2110 rfcomm_dlc_clear_timer(d);
2111 if (status || encrypt == 0x00) {
2112 set_bit(RFCOMM_ENC_DROP, &d->flags);
2113 continue;
2114 }
2115 }
2116
2117 if (d->state == BT_CONNECTED && !status && encrypt == 0x00) {
2118 if (d->sec_level == BT_SECURITY_MEDIUM) {
2119 set_bit(RFCOMM_SEC_PENDING, &d->flags);
2120 rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
2121 continue;
2122 } else if (d->sec_level == BT_SECURITY_HIGH ||
2123 d->sec_level == BT_SECURITY_FIPS) {
2124 set_bit(RFCOMM_ENC_DROP, &d->flags);
2125 continue;
2126 }
2127 }
2128
2129 if (!test_and_clear_bit(RFCOMM_AUTH_PENDING, &d->flags))
2130 continue;
2131
2132 if (!status && hci_conn_check_secure(conn, d->sec_level))
2133 set_bit(RFCOMM_AUTH_ACCEPT, &d->flags);
2134 else
2135 set_bit(RFCOMM_AUTH_REJECT, &d->flags);
2136 }
2137
2138 rfcomm_schedule();
2139 }
2140
2141 static struct hci_cb rfcomm_cb = {
2142 .name = "RFCOMM",
2143 .security_cfm = rfcomm_security_cfm
2144 };
2145
rfcomm_dlc_debugfs_show(struct seq_file * f,void * x)2146 static int rfcomm_dlc_debugfs_show(struct seq_file *f, void *x)
2147 {
2148 struct rfcomm_session *s;
2149
2150 rfcomm_lock();
2151
2152 list_for_each_entry(s, &session_list, list) {
2153 struct l2cap_chan *chan = l2cap_pi(s->sock->sk)->chan;
2154 struct rfcomm_dlc *d;
2155 list_for_each_entry(d, &s->dlcs, list) {
2156 seq_printf(f, "%pMR %pMR %ld %d %d %d %d\n",
2157 &chan->src, &chan->dst,
2158 d->state, d->dlci, d->mtu,
2159 d->rx_credits, d->tx_credits);
2160 }
2161 }
2162
2163 rfcomm_unlock();
2164
2165 return 0;
2166 }
2167
2168 DEFINE_SHOW_ATTRIBUTE(rfcomm_dlc_debugfs);
2169
2170 static struct dentry *rfcomm_dlc_debugfs;
2171
2172 /* ---- Initialization ---- */
rfcomm_init(void)2173 static int __init rfcomm_init(void)
2174 {
2175 int err;
2176
2177 hci_register_cb(&rfcomm_cb);
2178
2179 rfcomm_thread = kthread_run(rfcomm_run, NULL, "krfcommd");
2180 if (IS_ERR(rfcomm_thread)) {
2181 err = PTR_ERR(rfcomm_thread);
2182 goto unregister;
2183 }
2184
2185 err = rfcomm_init_ttys();
2186 if (err < 0)
2187 goto stop;
2188
2189 err = rfcomm_init_sockets();
2190 if (err < 0)
2191 goto cleanup;
2192
2193 BT_INFO("RFCOMM ver %s", VERSION);
2194
2195 if (IS_ERR_OR_NULL(bt_debugfs))
2196 return 0;
2197
2198 rfcomm_dlc_debugfs = debugfs_create_file("rfcomm_dlc", 0444,
2199 bt_debugfs, NULL,
2200 &rfcomm_dlc_debugfs_fops);
2201
2202 return 0;
2203
2204 cleanup:
2205 rfcomm_cleanup_ttys();
2206
2207 stop:
2208 kthread_stop(rfcomm_thread);
2209
2210 unregister:
2211 hci_unregister_cb(&rfcomm_cb);
2212
2213 return err;
2214 }
2215
rfcomm_exit(void)2216 static void __exit rfcomm_exit(void)
2217 {
2218 debugfs_remove(rfcomm_dlc_debugfs);
2219
2220 hci_unregister_cb(&rfcomm_cb);
2221
2222 kthread_stop(rfcomm_thread);
2223
2224 rfcomm_cleanup_ttys();
2225
2226 rfcomm_cleanup_sockets();
2227 }
2228
2229 module_init(rfcomm_init);
2230 module_exit(rfcomm_exit);
2231
2232 module_param(disable_cfc, bool, 0644);
2233 MODULE_PARM_DESC(disable_cfc, "Disable credit based flow control");
2234
2235 module_param(channel_mtu, int, 0644);
2236 MODULE_PARM_DESC(channel_mtu, "Default MTU for the RFCOMM channel");
2237
2238 module_param(l2cap_ertm, bool, 0644);
2239 MODULE_PARM_DESC(l2cap_ertm, "Use L2CAP ERTM mode for connection");
2240
2241 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
2242 MODULE_DESCRIPTION("Bluetooth RFCOMM ver " VERSION);
2243 MODULE_VERSION(VERSION);
2244 MODULE_LICENSE("GPL");
2245 MODULE_ALIAS("bt-proto-3");
2246
