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_frag(struct rfcomm_dlc * d,struct sk_buff * frag)552 static int rfcomm_dlc_send_frag(struct rfcomm_dlc *d, struct sk_buff *frag)
553 {
554 int len = frag->len;
555
556 BT_DBG("dlc %p mtu %d len %d", d, d->mtu, len);
557
558 if (len > d->mtu)
559 return -EINVAL;
560
561 rfcomm_make_uih(frag, d->addr);
562 __skb_queue_tail(&d->tx_queue, frag);
563
564 return len;
565 }
566
rfcomm_dlc_send(struct rfcomm_dlc * d,struct sk_buff * skb)567 int rfcomm_dlc_send(struct rfcomm_dlc *d, struct sk_buff *skb)
568 {
569 unsigned long flags;
570 struct sk_buff *frag, *next;
571 int len;
572
573 if (d->state != BT_CONNECTED)
574 return -ENOTCONN;
575
576 frag = skb_shinfo(skb)->frag_list;
577 skb_shinfo(skb)->frag_list = NULL;
578
579 /* Queue all fragments atomically. */
580 spin_lock_irqsave(&d->tx_queue.lock, flags);
581
582 len = rfcomm_dlc_send_frag(d, skb);
583 if (len < 0 || !frag)
584 goto unlock;
585
586 for (; frag; frag = next) {
587 int ret;
588
589 next = frag->next;
590
591 ret = rfcomm_dlc_send_frag(d, frag);
592 if (ret < 0) {
593 kfree_skb(frag);
594 goto unlock;
595 }
596
597 len += ret;
598 }
599
600 unlock:
601 spin_unlock_irqrestore(&d->tx_queue.lock, flags);
602
603 if (len > 0 && !test_bit(RFCOMM_TX_THROTTLED, &d->flags))
604 rfcomm_schedule();
605 return len;
606 }
607
rfcomm_dlc_send_noerror(struct rfcomm_dlc * d,struct sk_buff * skb)608 void rfcomm_dlc_send_noerror(struct rfcomm_dlc *d, struct sk_buff *skb)
609 {
610 int len = skb->len;
611
612 BT_DBG("dlc %p mtu %d len %d", d, d->mtu, len);
613
614 rfcomm_make_uih(skb, d->addr);
615 skb_queue_tail(&d->tx_queue, skb);
616
617 if (d->state == BT_CONNECTED &&
618 !test_bit(RFCOMM_TX_THROTTLED, &d->flags))
619 rfcomm_schedule();
620 }
621
__rfcomm_dlc_throttle(struct rfcomm_dlc * d)622 void __rfcomm_dlc_throttle(struct rfcomm_dlc *d)
623 {
624 BT_DBG("dlc %p state %ld", d, d->state);
625
626 if (!d->cfc) {
627 d->v24_sig |= RFCOMM_V24_FC;
628 set_bit(RFCOMM_MSC_PENDING, &d->flags);
629 }
630 rfcomm_schedule();
631 }
632
__rfcomm_dlc_unthrottle(struct rfcomm_dlc * d)633 void __rfcomm_dlc_unthrottle(struct rfcomm_dlc *d)
634 {
635 BT_DBG("dlc %p state %ld", d, d->state);
636
637 if (!d->cfc) {
638 d->v24_sig &= ~RFCOMM_V24_FC;
639 set_bit(RFCOMM_MSC_PENDING, &d->flags);
640 }
641 rfcomm_schedule();
642 }
643
644 /*
645 Set/get modem status functions use _local_ status i.e. what we report
646 to the other side.
647 Remote status is provided by dlc->modem_status() callback.
648 */
rfcomm_dlc_set_modem_status(struct rfcomm_dlc * d,u8 v24_sig)649 int rfcomm_dlc_set_modem_status(struct rfcomm_dlc *d, u8 v24_sig)
650 {
651 BT_DBG("dlc %p state %ld v24_sig 0x%x",
652 d, d->state, v24_sig);
653
654 if (test_bit(RFCOMM_RX_THROTTLED, &d->flags))
655 v24_sig |= RFCOMM_V24_FC;
656 else
657 v24_sig &= ~RFCOMM_V24_FC;
658
659 d->v24_sig = v24_sig;
660
661 if (!test_and_set_bit(RFCOMM_MSC_PENDING, &d->flags))
662 rfcomm_schedule();
663
664 return 0;
665 }
666
rfcomm_dlc_get_modem_status(struct rfcomm_dlc * d,u8 * v24_sig)667 int rfcomm_dlc_get_modem_status(struct rfcomm_dlc *d, u8 *v24_sig)
668 {
669 BT_DBG("dlc %p state %ld v24_sig 0x%x",
670 d, d->state, d->v24_sig);
671
672 *v24_sig = d->v24_sig;
673 return 0;
674 }
675
676 /* ---- RFCOMM sessions ---- */
rfcomm_session_add(struct socket * sock,int state)677 static struct rfcomm_session *rfcomm_session_add(struct socket *sock, int state)
678 {
679 struct rfcomm_session *s = kzalloc(sizeof(*s), GFP_KERNEL);
680
681 if (!s)
682 return NULL;
683
684 BT_DBG("session %p sock %p", s, sock);
685
686 timer_setup(&s->timer, rfcomm_session_timeout, 0);
687
688 INIT_LIST_HEAD(&s->dlcs);
689 s->state = state;
690 s->sock = sock;
691
692 s->mtu = RFCOMM_DEFAULT_MTU;
693 s->cfc = disable_cfc ? RFCOMM_CFC_DISABLED : RFCOMM_CFC_UNKNOWN;
694
695 /* Do not increment module usage count for listening sessions.
696 * Otherwise we won't be able to unload the module. */
697 if (state != BT_LISTEN)
698 if (!try_module_get(THIS_MODULE)) {
699 kfree(s);
700 return NULL;
701 }
702
703 list_add(&s->list, &session_list);
704
705 return s;
706 }
707
rfcomm_session_del(struct rfcomm_session * s)708 static struct rfcomm_session *rfcomm_session_del(struct rfcomm_session *s)
709 {
710 int state = s->state;
711
712 BT_DBG("session %p state %ld", s, s->state);
713
714 list_del(&s->list);
715
716 rfcomm_session_clear_timer(s);
717 sock_release(s->sock);
718 kfree(s);
719
720 if (state != BT_LISTEN)
721 module_put(THIS_MODULE);
722
723 return NULL;
724 }
725
rfcomm_session_get(bdaddr_t * src,bdaddr_t * dst)726 static struct rfcomm_session *rfcomm_session_get(bdaddr_t *src, bdaddr_t *dst)
727 {
728 struct rfcomm_session *s, *n;
729 struct l2cap_chan *chan;
730 list_for_each_entry_safe(s, n, &session_list, list) {
731 chan = l2cap_pi(s->sock->sk)->chan;
732
733 if ((!bacmp(src, BDADDR_ANY) || !bacmp(&chan->src, src)) &&
734 !bacmp(&chan->dst, dst))
735 return s;
736 }
737 return NULL;
738 }
739
rfcomm_session_close(struct rfcomm_session * s,int err)740 static struct rfcomm_session *rfcomm_session_close(struct rfcomm_session *s,
741 int err)
742 {
743 struct rfcomm_dlc *d, *n;
744
745 s->state = BT_CLOSED;
746
747 BT_DBG("session %p state %ld err %d", s, s->state, err);
748
749 /* Close all dlcs */
750 list_for_each_entry_safe(d, n, &s->dlcs, list) {
751 d->state = BT_CLOSED;
752 __rfcomm_dlc_close(d, err);
753 }
754
755 rfcomm_session_clear_timer(s);
756 return rfcomm_session_del(s);
757 }
758
rfcomm_session_create(bdaddr_t * src,bdaddr_t * dst,u8 sec_level,int * err)759 static struct rfcomm_session *rfcomm_session_create(bdaddr_t *src,
760 bdaddr_t *dst,
761 u8 sec_level,
762 int *err)
763 {
764 struct rfcomm_session *s = NULL;
765 struct sockaddr_l2 addr;
766 struct socket *sock;
767 struct sock *sk;
768
769 BT_DBG("%pMR -> %pMR", src, dst);
770
771 *err = rfcomm_l2sock_create(&sock);
772 if (*err < 0)
773 return NULL;
774
775 bacpy(&addr.l2_bdaddr, src);
776 addr.l2_family = AF_BLUETOOTH;
777 addr.l2_psm = 0;
778 addr.l2_cid = 0;
779 addr.l2_bdaddr_type = BDADDR_BREDR;
780 *err = kernel_bind(sock, (struct sockaddr *) &addr, sizeof(addr));
781 if (*err < 0)
782 goto failed;
783
784 /* Set L2CAP options */
785 sk = sock->sk;
786 lock_sock(sk);
787 /* Set MTU to 0 so L2CAP can auto select the MTU */
788 l2cap_pi(sk)->chan->imtu = 0;
789 l2cap_pi(sk)->chan->sec_level = sec_level;
790 if (l2cap_ertm)
791 l2cap_pi(sk)->chan->mode = L2CAP_MODE_ERTM;
792 release_sock(sk);
793
794 s = rfcomm_session_add(sock, BT_BOUND);
795 if (!s) {
796 *err = -ENOMEM;
797 goto failed;
798 }
799
800 s->initiator = 1;
801
802 bacpy(&addr.l2_bdaddr, dst);
803 addr.l2_family = AF_BLUETOOTH;
804 addr.l2_psm = cpu_to_le16(L2CAP_PSM_RFCOMM);
805 addr.l2_cid = 0;
806 addr.l2_bdaddr_type = BDADDR_BREDR;
807 *err = kernel_connect(sock, (struct sockaddr *) &addr, sizeof(addr), O_NONBLOCK);
808 if (*err == 0 || *err == -EINPROGRESS)
809 return s;
810
811 return rfcomm_session_del(s);
812
813 failed:
814 sock_release(sock);
815 return NULL;
816 }
817
rfcomm_session_getaddr(struct rfcomm_session * s,bdaddr_t * src,bdaddr_t * dst)818 void rfcomm_session_getaddr(struct rfcomm_session *s, bdaddr_t *src, bdaddr_t *dst)
819 {
820 struct l2cap_chan *chan = l2cap_pi(s->sock->sk)->chan;
821 if (src)
822 bacpy(src, &chan->src);
823 if (dst)
824 bacpy(dst, &chan->dst);
825 }
826
827 /* ---- RFCOMM frame sending ---- */
rfcomm_send_frame(struct rfcomm_session * s,u8 * data,int len)828 static int rfcomm_send_frame(struct rfcomm_session *s, u8 *data, int len)
829 {
830 struct kvec iv = { data, len };
831 struct msghdr msg;
832
833 BT_DBG("session %p len %d", s, len);
834
835 memset(&msg, 0, sizeof(msg));
836
837 return kernel_sendmsg(s->sock, &msg, &iv, 1, len);
838 }
839
rfcomm_send_cmd(struct rfcomm_session * s,struct rfcomm_cmd * cmd)840 static int rfcomm_send_cmd(struct rfcomm_session *s, struct rfcomm_cmd *cmd)
841 {
842 BT_DBG("%p cmd %u", s, cmd->ctrl);
843
844 return rfcomm_send_frame(s, (void *) cmd, sizeof(*cmd));
845 }
846
rfcomm_send_sabm(struct rfcomm_session * s,u8 dlci)847 static int rfcomm_send_sabm(struct rfcomm_session *s, u8 dlci)
848 {
849 struct rfcomm_cmd cmd;
850
851 BT_DBG("%p dlci %d", s, dlci);
852
853 cmd.addr = __addr(s->initiator, dlci);
854 cmd.ctrl = __ctrl(RFCOMM_SABM, 1);
855 cmd.len = __len8(0);
856 cmd.fcs = __fcs2((u8 *) &cmd);
857
858 return rfcomm_send_cmd(s, &cmd);
859 }
860
rfcomm_send_ua(struct rfcomm_session * s,u8 dlci)861 static int rfcomm_send_ua(struct rfcomm_session *s, u8 dlci)
862 {
863 struct rfcomm_cmd cmd;
864
865 BT_DBG("%p dlci %d", s, dlci);
866
867 cmd.addr = __addr(!s->initiator, dlci);
868 cmd.ctrl = __ctrl(RFCOMM_UA, 1);
869 cmd.len = __len8(0);
870 cmd.fcs = __fcs2((u8 *) &cmd);
871
872 return rfcomm_send_cmd(s, &cmd);
873 }
874
rfcomm_send_disc(struct rfcomm_session * s,u8 dlci)875 static int rfcomm_send_disc(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_DISC, 1);
883 cmd.len = __len8(0);
884 cmd.fcs = __fcs2((u8 *) &cmd);
885
886 return rfcomm_send_cmd(s, &cmd);
887 }
888
rfcomm_queue_disc(struct rfcomm_dlc * d)889 static int rfcomm_queue_disc(struct rfcomm_dlc *d)
890 {
891 struct rfcomm_cmd *cmd;
892 struct sk_buff *skb;
893
894 BT_DBG("dlc %p dlci %d", d, d->dlci);
895
896 skb = alloc_skb(sizeof(*cmd), GFP_KERNEL);
897 if (!skb)
898 return -ENOMEM;
899
900 cmd = __skb_put(skb, sizeof(*cmd));
901 cmd->addr = d->addr;
902 cmd->ctrl = __ctrl(RFCOMM_DISC, 1);
903 cmd->len = __len8(0);
904 cmd->fcs = __fcs2((u8 *) cmd);
905
906 skb_queue_tail(&d->tx_queue, skb);
907 rfcomm_schedule();
908 return 0;
909 }
910
rfcomm_send_dm(struct rfcomm_session * s,u8 dlci)911 static int rfcomm_send_dm(struct rfcomm_session *s, u8 dlci)
912 {
913 struct rfcomm_cmd cmd;
914
915 BT_DBG("%p dlci %d", s, dlci);
916
917 cmd.addr = __addr(!s->initiator, dlci);
918 cmd.ctrl = __ctrl(RFCOMM_DM, 1);
919 cmd.len = __len8(0);
920 cmd.fcs = __fcs2((u8 *) &cmd);
921
922 return rfcomm_send_cmd(s, &cmd);
923 }
924
rfcomm_send_nsc(struct rfcomm_session * s,int cr,u8 type)925 static int rfcomm_send_nsc(struct rfcomm_session *s, int cr, u8 type)
926 {
927 struct rfcomm_hdr *hdr;
928 struct rfcomm_mcc *mcc;
929 u8 buf[16], *ptr = buf;
930
931 BT_DBG("%p cr %d type %d", s, cr, type);
932
933 hdr = (void *) ptr; ptr += sizeof(*hdr);
934 hdr->addr = __addr(s->initiator, 0);
935 hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
936 hdr->len = __len8(sizeof(*mcc) + 1);
937
938 mcc = (void *) ptr; ptr += sizeof(*mcc);
939 mcc->type = __mcc_type(0, RFCOMM_NSC);
940 mcc->len = __len8(1);
941
942 /* Type that we didn't like */
943 *ptr = __mcc_type(cr, type); ptr++;
944
945 *ptr = __fcs(buf); ptr++;
946
947 return rfcomm_send_frame(s, buf, ptr - buf);
948 }
949
rfcomm_send_pn(struct rfcomm_session * s,int cr,struct rfcomm_dlc * d)950 static int rfcomm_send_pn(struct rfcomm_session *s, int cr, struct rfcomm_dlc *d)
951 {
952 struct rfcomm_hdr *hdr;
953 struct rfcomm_mcc *mcc;
954 struct rfcomm_pn *pn;
955 u8 buf[16], *ptr = buf;
956
957 BT_DBG("%p cr %d dlci %d mtu %d", s, cr, d->dlci, d->mtu);
958
959 hdr = (void *) ptr; ptr += sizeof(*hdr);
960 hdr->addr = __addr(s->initiator, 0);
961 hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
962 hdr->len = __len8(sizeof(*mcc) + sizeof(*pn));
963
964 mcc = (void *) ptr; ptr += sizeof(*mcc);
965 mcc->type = __mcc_type(cr, RFCOMM_PN);
966 mcc->len = __len8(sizeof(*pn));
967
968 pn = (void *) ptr; ptr += sizeof(*pn);
969 pn->dlci = d->dlci;
970 pn->priority = d->priority;
971 pn->ack_timer = 0;
972 pn->max_retrans = 0;
973
974 if (s->cfc) {
975 pn->flow_ctrl = cr ? 0xf0 : 0xe0;
976 pn->credits = RFCOMM_DEFAULT_CREDITS;
977 } else {
978 pn->flow_ctrl = 0;
979 pn->credits = 0;
980 }
981
982 if (cr && channel_mtu >= 0)
983 pn->mtu = cpu_to_le16(channel_mtu);
984 else
985 pn->mtu = cpu_to_le16(d->mtu);
986
987 *ptr = __fcs(buf); ptr++;
988
989 return rfcomm_send_frame(s, buf, ptr - buf);
990 }
991
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)992 int rfcomm_send_rpn(struct rfcomm_session *s, int cr, u8 dlci,
993 u8 bit_rate, u8 data_bits, u8 stop_bits,
994 u8 parity, u8 flow_ctrl_settings,
995 u8 xon_char, u8 xoff_char, u16 param_mask)
996 {
997 struct rfcomm_hdr *hdr;
998 struct rfcomm_mcc *mcc;
999 struct rfcomm_rpn *rpn;
1000 u8 buf[16], *ptr = buf;
1001
1002 BT_DBG("%p cr %d dlci %d bit_r 0x%x data_b 0x%x stop_b 0x%x parity 0x%x"
1003 " flwc_s 0x%x xon_c 0x%x xoff_c 0x%x p_mask 0x%x",
1004 s, cr, dlci, bit_rate, data_bits, stop_bits, parity,
1005 flow_ctrl_settings, xon_char, xoff_char, param_mask);
1006
1007 hdr = (void *) ptr; ptr += sizeof(*hdr);
1008 hdr->addr = __addr(s->initiator, 0);
1009 hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1010 hdr->len = __len8(sizeof(*mcc) + sizeof(*rpn));
1011
1012 mcc = (void *) ptr; ptr += sizeof(*mcc);
1013 mcc->type = __mcc_type(cr, RFCOMM_RPN);
1014 mcc->len = __len8(sizeof(*rpn));
1015
1016 rpn = (void *) ptr; ptr += sizeof(*rpn);
1017 rpn->dlci = __addr(1, dlci);
1018 rpn->bit_rate = bit_rate;
1019 rpn->line_settings = __rpn_line_settings(data_bits, stop_bits, parity);
1020 rpn->flow_ctrl = flow_ctrl_settings;
1021 rpn->xon_char = xon_char;
1022 rpn->xoff_char = xoff_char;
1023 rpn->param_mask = cpu_to_le16(param_mask);
1024
1025 *ptr = __fcs(buf); ptr++;
1026
1027 return rfcomm_send_frame(s, buf, ptr - buf);
1028 }
1029
rfcomm_send_rls(struct rfcomm_session * s,int cr,u8 dlci,u8 status)1030 static int rfcomm_send_rls(struct rfcomm_session *s, int cr, u8 dlci, u8 status)
1031 {
1032 struct rfcomm_hdr *hdr;
1033 struct rfcomm_mcc *mcc;
1034 struct rfcomm_rls *rls;
1035 u8 buf[16], *ptr = buf;
1036
1037 BT_DBG("%p cr %d status 0x%x", s, cr, status);
1038
1039 hdr = (void *) ptr; ptr += sizeof(*hdr);
1040 hdr->addr = __addr(s->initiator, 0);
1041 hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1042 hdr->len = __len8(sizeof(*mcc) + sizeof(*rls));
1043
1044 mcc = (void *) ptr; ptr += sizeof(*mcc);
1045 mcc->type = __mcc_type(cr, RFCOMM_RLS);
1046 mcc->len = __len8(sizeof(*rls));
1047
1048 rls = (void *) ptr; ptr += sizeof(*rls);
1049 rls->dlci = __addr(1, dlci);
1050 rls->status = status;
1051
1052 *ptr = __fcs(buf); ptr++;
1053
1054 return rfcomm_send_frame(s, buf, ptr - buf);
1055 }
1056
rfcomm_send_msc(struct rfcomm_session * s,int cr,u8 dlci,u8 v24_sig)1057 static int rfcomm_send_msc(struct rfcomm_session *s, int cr, u8 dlci, u8 v24_sig)
1058 {
1059 struct rfcomm_hdr *hdr;
1060 struct rfcomm_mcc *mcc;
1061 struct rfcomm_msc *msc;
1062 u8 buf[16], *ptr = buf;
1063
1064 BT_DBG("%p cr %d v24 0x%x", s, cr, v24_sig);
1065
1066 hdr = (void *) ptr; ptr += sizeof(*hdr);
1067 hdr->addr = __addr(s->initiator, 0);
1068 hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1069 hdr->len = __len8(sizeof(*mcc) + sizeof(*msc));
1070
1071 mcc = (void *) ptr; ptr += sizeof(*mcc);
1072 mcc->type = __mcc_type(cr, RFCOMM_MSC);
1073 mcc->len = __len8(sizeof(*msc));
1074
1075 msc = (void *) ptr; ptr += sizeof(*msc);
1076 msc->dlci = __addr(1, dlci);
1077 msc->v24_sig = v24_sig | 0x01;
1078
1079 *ptr = __fcs(buf); ptr++;
1080
1081 return rfcomm_send_frame(s, buf, ptr - buf);
1082 }
1083
rfcomm_send_fcoff(struct rfcomm_session * s,int cr)1084 static int rfcomm_send_fcoff(struct rfcomm_session *s, int cr)
1085 {
1086 struct rfcomm_hdr *hdr;
1087 struct rfcomm_mcc *mcc;
1088 u8 buf[16], *ptr = buf;
1089
1090 BT_DBG("%p cr %d", s, cr);
1091
1092 hdr = (void *) ptr; ptr += sizeof(*hdr);
1093 hdr->addr = __addr(s->initiator, 0);
1094 hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1095 hdr->len = __len8(sizeof(*mcc));
1096
1097 mcc = (void *) ptr; ptr += sizeof(*mcc);
1098 mcc->type = __mcc_type(cr, RFCOMM_FCOFF);
1099 mcc->len = __len8(0);
1100
1101 *ptr = __fcs(buf); ptr++;
1102
1103 return rfcomm_send_frame(s, buf, ptr - buf);
1104 }
1105
rfcomm_send_fcon(struct rfcomm_session * s,int cr)1106 static int rfcomm_send_fcon(struct rfcomm_session *s, int cr)
1107 {
1108 struct rfcomm_hdr *hdr;
1109 struct rfcomm_mcc *mcc;
1110 u8 buf[16], *ptr = buf;
1111
1112 BT_DBG("%p cr %d", s, cr);
1113
1114 hdr = (void *) ptr; ptr += sizeof(*hdr);
1115 hdr->addr = __addr(s->initiator, 0);
1116 hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1117 hdr->len = __len8(sizeof(*mcc));
1118
1119 mcc = (void *) ptr; ptr += sizeof(*mcc);
1120 mcc->type = __mcc_type(cr, RFCOMM_FCON);
1121 mcc->len = __len8(0);
1122
1123 *ptr = __fcs(buf); ptr++;
1124
1125 return rfcomm_send_frame(s, buf, ptr - buf);
1126 }
1127
rfcomm_send_test(struct rfcomm_session * s,int cr,u8 * pattern,int len)1128 static int rfcomm_send_test(struct rfcomm_session *s, int cr, u8 *pattern, int len)
1129 {
1130 struct socket *sock = s->sock;
1131 struct kvec iv[3];
1132 struct msghdr msg;
1133 unsigned char hdr[5], crc[1];
1134
1135 if (len > 125)
1136 return -EINVAL;
1137
1138 BT_DBG("%p cr %d", s, cr);
1139
1140 hdr[0] = __addr(s->initiator, 0);
1141 hdr[1] = __ctrl(RFCOMM_UIH, 0);
1142 hdr[2] = 0x01 | ((len + 2) << 1);
1143 hdr[3] = 0x01 | ((cr & 0x01) << 1) | (RFCOMM_TEST << 2);
1144 hdr[4] = 0x01 | (len << 1);
1145
1146 crc[0] = __fcs(hdr);
1147
1148 iv[0].iov_base = hdr;
1149 iv[0].iov_len = 5;
1150 iv[1].iov_base = pattern;
1151 iv[1].iov_len = len;
1152 iv[2].iov_base = crc;
1153 iv[2].iov_len = 1;
1154
1155 memset(&msg, 0, sizeof(msg));
1156
1157 return kernel_sendmsg(sock, &msg, iv, 3, 6 + len);
1158 }
1159
rfcomm_send_credits(struct rfcomm_session * s,u8 addr,u8 credits)1160 static int rfcomm_send_credits(struct rfcomm_session *s, u8 addr, u8 credits)
1161 {
1162 struct rfcomm_hdr *hdr;
1163 u8 buf[16], *ptr = buf;
1164
1165 BT_DBG("%p addr %d credits %d", s, addr, credits);
1166
1167 hdr = (void *) ptr; ptr += sizeof(*hdr);
1168 hdr->addr = addr;
1169 hdr->ctrl = __ctrl(RFCOMM_UIH, 1);
1170 hdr->len = __len8(0);
1171
1172 *ptr = credits; ptr++;
1173
1174 *ptr = __fcs(buf); ptr++;
1175
1176 return rfcomm_send_frame(s, buf, ptr - buf);
1177 }
1178
rfcomm_make_uih(struct sk_buff * skb,u8 addr)1179 static void rfcomm_make_uih(struct sk_buff *skb, u8 addr)
1180 {
1181 struct rfcomm_hdr *hdr;
1182 int len = skb->len;
1183 u8 *crc;
1184
1185 if (len > 127) {
1186 hdr = skb_push(skb, 4);
1187 put_unaligned(cpu_to_le16(__len16(len)), (__le16 *) &hdr->len);
1188 } else {
1189 hdr = skb_push(skb, 3);
1190 hdr->len = __len8(len);
1191 }
1192 hdr->addr = addr;
1193 hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1194
1195 crc = skb_put(skb, 1);
1196 *crc = __fcs((void *) hdr);
1197 }
1198
1199 /* ---- RFCOMM frame reception ---- */
rfcomm_recv_ua(struct rfcomm_session * s,u8 dlci)1200 static struct rfcomm_session *rfcomm_recv_ua(struct rfcomm_session *s, u8 dlci)
1201 {
1202 BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1203
1204 if (dlci) {
1205 /* Data channel */
1206 struct rfcomm_dlc *d = rfcomm_dlc_get(s, dlci);
1207 if (!d) {
1208 rfcomm_send_dm(s, dlci);
1209 return s;
1210 }
1211
1212 switch (d->state) {
1213 case BT_CONNECT:
1214 rfcomm_dlc_clear_timer(d);
1215
1216 rfcomm_dlc_lock(d);
1217 d->state = BT_CONNECTED;
1218 d->state_change(d, 0);
1219 rfcomm_dlc_unlock(d);
1220
1221 rfcomm_send_msc(s, 1, dlci, d->v24_sig);
1222 break;
1223
1224 case BT_DISCONN:
1225 d->state = BT_CLOSED;
1226 __rfcomm_dlc_close(d, 0);
1227
1228 if (list_empty(&s->dlcs)) {
1229 s->state = BT_DISCONN;
1230 rfcomm_send_disc(s, 0);
1231 rfcomm_session_clear_timer(s);
1232 }
1233
1234 break;
1235 }
1236 } else {
1237 /* Control channel */
1238 switch (s->state) {
1239 case BT_CONNECT:
1240 s->state = BT_CONNECTED;
1241 rfcomm_process_connect(s);
1242 break;
1243
1244 case BT_DISCONN:
1245 s = rfcomm_session_close(s, ECONNRESET);
1246 break;
1247 }
1248 }
1249 return s;
1250 }
1251
rfcomm_recv_dm(struct rfcomm_session * s,u8 dlci)1252 static struct rfcomm_session *rfcomm_recv_dm(struct rfcomm_session *s, u8 dlci)
1253 {
1254 int err = 0;
1255
1256 BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1257
1258 if (dlci) {
1259 /* Data DLC */
1260 struct rfcomm_dlc *d = rfcomm_dlc_get(s, dlci);
1261 if (d) {
1262 if (d->state == BT_CONNECT || d->state == BT_CONFIG)
1263 err = ECONNREFUSED;
1264 else
1265 err = ECONNRESET;
1266
1267 d->state = BT_CLOSED;
1268 __rfcomm_dlc_close(d, err);
1269 }
1270 } else {
1271 if (s->state == BT_CONNECT)
1272 err = ECONNREFUSED;
1273 else
1274 err = ECONNRESET;
1275
1276 s = rfcomm_session_close(s, err);
1277 }
1278 return s;
1279 }
1280
rfcomm_recv_disc(struct rfcomm_session * s,u8 dlci)1281 static struct rfcomm_session *rfcomm_recv_disc(struct rfcomm_session *s,
1282 u8 dlci)
1283 {
1284 int err = 0;
1285
1286 BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1287
1288 if (dlci) {
1289 struct rfcomm_dlc *d = rfcomm_dlc_get(s, dlci);
1290 if (d) {
1291 rfcomm_send_ua(s, dlci);
1292
1293 if (d->state == BT_CONNECT || d->state == BT_CONFIG)
1294 err = ECONNREFUSED;
1295 else
1296 err = ECONNRESET;
1297
1298 d->state = BT_CLOSED;
1299 __rfcomm_dlc_close(d, err);
1300 } else
1301 rfcomm_send_dm(s, dlci);
1302
1303 } else {
1304 rfcomm_send_ua(s, 0);
1305
1306 if (s->state == BT_CONNECT)
1307 err = ECONNREFUSED;
1308 else
1309 err = ECONNRESET;
1310
1311 s = rfcomm_session_close(s, err);
1312 }
1313 return s;
1314 }
1315
rfcomm_dlc_accept(struct rfcomm_dlc * d)1316 void rfcomm_dlc_accept(struct rfcomm_dlc *d)
1317 {
1318 struct sock *sk = d->session->sock->sk;
1319 struct l2cap_conn *conn = l2cap_pi(sk)->chan->conn;
1320
1321 BT_DBG("dlc %p", d);
1322
1323 rfcomm_send_ua(d->session, d->dlci);
1324
1325 rfcomm_dlc_clear_timer(d);
1326
1327 rfcomm_dlc_lock(d);
1328 d->state = BT_CONNECTED;
1329 d->state_change(d, 0);
1330 rfcomm_dlc_unlock(d);
1331
1332 if (d->role_switch)
1333 hci_conn_switch_role(conn->hcon, 0x00);
1334
1335 rfcomm_send_msc(d->session, 1, d->dlci, d->v24_sig);
1336 }
1337
rfcomm_check_accept(struct rfcomm_dlc * d)1338 static void rfcomm_check_accept(struct rfcomm_dlc *d)
1339 {
1340 if (rfcomm_check_security(d)) {
1341 if (d->defer_setup) {
1342 set_bit(RFCOMM_DEFER_SETUP, &d->flags);
1343 rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1344
1345 rfcomm_dlc_lock(d);
1346 d->state = BT_CONNECT2;
1347 d->state_change(d, 0);
1348 rfcomm_dlc_unlock(d);
1349 } else
1350 rfcomm_dlc_accept(d);
1351 } else {
1352 set_bit(RFCOMM_AUTH_PENDING, &d->flags);
1353 rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1354 }
1355 }
1356
rfcomm_recv_sabm(struct rfcomm_session * s,u8 dlci)1357 static int rfcomm_recv_sabm(struct rfcomm_session *s, u8 dlci)
1358 {
1359 struct rfcomm_dlc *d;
1360 u8 channel;
1361
1362 BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1363
1364 if (!dlci) {
1365 rfcomm_send_ua(s, 0);
1366
1367 if (s->state == BT_OPEN) {
1368 s->state = BT_CONNECTED;
1369 rfcomm_process_connect(s);
1370 }
1371 return 0;
1372 }
1373
1374 /* Check if DLC exists */
1375 d = rfcomm_dlc_get(s, dlci);
1376 if (d) {
1377 if (d->state == BT_OPEN) {
1378 /* DLC was previously opened by PN request */
1379 rfcomm_check_accept(d);
1380 }
1381 return 0;
1382 }
1383
1384 /* Notify socket layer about incoming connection */
1385 channel = __srv_channel(dlci);
1386 if (rfcomm_connect_ind(s, channel, &d)) {
1387 d->dlci = dlci;
1388 d->addr = __addr(s->initiator, dlci);
1389 rfcomm_dlc_link(s, d);
1390
1391 rfcomm_check_accept(d);
1392 } else {
1393 rfcomm_send_dm(s, dlci);
1394 }
1395
1396 return 0;
1397 }
1398
rfcomm_apply_pn(struct rfcomm_dlc * d,int cr,struct rfcomm_pn * pn)1399 static int rfcomm_apply_pn(struct rfcomm_dlc *d, int cr, struct rfcomm_pn *pn)
1400 {
1401 struct rfcomm_session *s = d->session;
1402
1403 BT_DBG("dlc %p state %ld dlci %d mtu %d fc 0x%x credits %d",
1404 d, d->state, d->dlci, pn->mtu, pn->flow_ctrl, pn->credits);
1405
1406 if ((pn->flow_ctrl == 0xf0 && s->cfc != RFCOMM_CFC_DISABLED) ||
1407 pn->flow_ctrl == 0xe0) {
1408 d->cfc = RFCOMM_CFC_ENABLED;
1409 d->tx_credits = pn->credits;
1410 } else {
1411 d->cfc = RFCOMM_CFC_DISABLED;
1412 set_bit(RFCOMM_TX_THROTTLED, &d->flags);
1413 }
1414
1415 if (s->cfc == RFCOMM_CFC_UNKNOWN)
1416 s->cfc = d->cfc;
1417
1418 d->priority = pn->priority;
1419
1420 d->mtu = __le16_to_cpu(pn->mtu);
1421
1422 if (cr && d->mtu > s->mtu)
1423 d->mtu = s->mtu;
1424
1425 return 0;
1426 }
1427
rfcomm_recv_pn(struct rfcomm_session * s,int cr,struct sk_buff * skb)1428 static int rfcomm_recv_pn(struct rfcomm_session *s, int cr, struct sk_buff *skb)
1429 {
1430 struct rfcomm_pn *pn = (void *) skb->data;
1431 struct rfcomm_dlc *d;
1432 u8 dlci = pn->dlci;
1433
1434 BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1435
1436 if (!dlci)
1437 return 0;
1438
1439 d = rfcomm_dlc_get(s, dlci);
1440 if (d) {
1441 if (cr) {
1442 /* PN request */
1443 rfcomm_apply_pn(d, cr, pn);
1444 rfcomm_send_pn(s, 0, d);
1445 } else {
1446 /* PN response */
1447 switch (d->state) {
1448 case BT_CONFIG:
1449 rfcomm_apply_pn(d, cr, pn);
1450
1451 d->state = BT_CONNECT;
1452 rfcomm_send_sabm(s, d->dlci);
1453 break;
1454 }
1455 }
1456 } else {
1457 u8 channel = __srv_channel(dlci);
1458
1459 if (!cr)
1460 return 0;
1461
1462 /* PN request for non existing DLC.
1463 * Assume incoming connection. */
1464 if (rfcomm_connect_ind(s, channel, &d)) {
1465 d->dlci = dlci;
1466 d->addr = __addr(s->initiator, dlci);
1467 rfcomm_dlc_link(s, d);
1468
1469 rfcomm_apply_pn(d, cr, pn);
1470
1471 d->state = BT_OPEN;
1472 rfcomm_send_pn(s, 0, d);
1473 } else {
1474 rfcomm_send_dm(s, dlci);
1475 }
1476 }
1477 return 0;
1478 }
1479
rfcomm_recv_rpn(struct rfcomm_session * s,int cr,int len,struct sk_buff * skb)1480 static int rfcomm_recv_rpn(struct rfcomm_session *s, int cr, int len, struct sk_buff *skb)
1481 {
1482 struct rfcomm_rpn *rpn = (void *) skb->data;
1483 u8 dlci = __get_dlci(rpn->dlci);
1484
1485 u8 bit_rate = 0;
1486 u8 data_bits = 0;
1487 u8 stop_bits = 0;
1488 u8 parity = 0;
1489 u8 flow_ctrl = 0;
1490 u8 xon_char = 0;
1491 u8 xoff_char = 0;
1492 u16 rpn_mask = RFCOMM_RPN_PM_ALL;
1493
1494 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",
1495 dlci, cr, len, rpn->bit_rate, rpn->line_settings, rpn->flow_ctrl,
1496 rpn->xon_char, rpn->xoff_char, rpn->param_mask);
1497
1498 if (!cr)
1499 return 0;
1500
1501 if (len == 1) {
1502 /* This is a request, return default (according to ETSI TS 07.10) settings */
1503 bit_rate = RFCOMM_RPN_BR_9600;
1504 data_bits = RFCOMM_RPN_DATA_8;
1505 stop_bits = RFCOMM_RPN_STOP_1;
1506 parity = RFCOMM_RPN_PARITY_NONE;
1507 flow_ctrl = RFCOMM_RPN_FLOW_NONE;
1508 xon_char = RFCOMM_RPN_XON_CHAR;
1509 xoff_char = RFCOMM_RPN_XOFF_CHAR;
1510 goto rpn_out;
1511 }
1512
1513 /* Check for sane values, ignore/accept bit_rate, 8 bits, 1 stop bit,
1514 * no parity, no flow control lines, normal XON/XOFF chars */
1515
1516 if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_BITRATE)) {
1517 bit_rate = rpn->bit_rate;
1518 if (bit_rate > RFCOMM_RPN_BR_230400) {
1519 BT_DBG("RPN bit rate mismatch 0x%x", bit_rate);
1520 bit_rate = RFCOMM_RPN_BR_9600;
1521 rpn_mask ^= RFCOMM_RPN_PM_BITRATE;
1522 }
1523 }
1524
1525 if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_DATA)) {
1526 data_bits = __get_rpn_data_bits(rpn->line_settings);
1527 if (data_bits != RFCOMM_RPN_DATA_8) {
1528 BT_DBG("RPN data bits mismatch 0x%x", data_bits);
1529 data_bits = RFCOMM_RPN_DATA_8;
1530 rpn_mask ^= RFCOMM_RPN_PM_DATA;
1531 }
1532 }
1533
1534 if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_STOP)) {
1535 stop_bits = __get_rpn_stop_bits(rpn->line_settings);
1536 if (stop_bits != RFCOMM_RPN_STOP_1) {
1537 BT_DBG("RPN stop bits mismatch 0x%x", stop_bits);
1538 stop_bits = RFCOMM_RPN_STOP_1;
1539 rpn_mask ^= RFCOMM_RPN_PM_STOP;
1540 }
1541 }
1542
1543 if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_PARITY)) {
1544 parity = __get_rpn_parity(rpn->line_settings);
1545 if (parity != RFCOMM_RPN_PARITY_NONE) {
1546 BT_DBG("RPN parity mismatch 0x%x", parity);
1547 parity = RFCOMM_RPN_PARITY_NONE;
1548 rpn_mask ^= RFCOMM_RPN_PM_PARITY;
1549 }
1550 }
1551
1552 if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_FLOW)) {
1553 flow_ctrl = rpn->flow_ctrl;
1554 if (flow_ctrl != RFCOMM_RPN_FLOW_NONE) {
1555 BT_DBG("RPN flow ctrl mismatch 0x%x", flow_ctrl);
1556 flow_ctrl = RFCOMM_RPN_FLOW_NONE;
1557 rpn_mask ^= RFCOMM_RPN_PM_FLOW;
1558 }
1559 }
1560
1561 if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_XON)) {
1562 xon_char = rpn->xon_char;
1563 if (xon_char != RFCOMM_RPN_XON_CHAR) {
1564 BT_DBG("RPN XON char mismatch 0x%x", xon_char);
1565 xon_char = RFCOMM_RPN_XON_CHAR;
1566 rpn_mask ^= RFCOMM_RPN_PM_XON;
1567 }
1568 }
1569
1570 if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_XOFF)) {
1571 xoff_char = rpn->xoff_char;
1572 if (xoff_char != RFCOMM_RPN_XOFF_CHAR) {
1573 BT_DBG("RPN XOFF char mismatch 0x%x", xoff_char);
1574 xoff_char = RFCOMM_RPN_XOFF_CHAR;
1575 rpn_mask ^= RFCOMM_RPN_PM_XOFF;
1576 }
1577 }
1578
1579 rpn_out:
1580 rfcomm_send_rpn(s, 0, dlci, bit_rate, data_bits, stop_bits,
1581 parity, flow_ctrl, xon_char, xoff_char, rpn_mask);
1582
1583 return 0;
1584 }
1585
rfcomm_recv_rls(struct rfcomm_session * s,int cr,struct sk_buff * skb)1586 static int rfcomm_recv_rls(struct rfcomm_session *s, int cr, struct sk_buff *skb)
1587 {
1588 struct rfcomm_rls *rls = (void *) skb->data;
1589 u8 dlci = __get_dlci(rls->dlci);
1590
1591 BT_DBG("dlci %d cr %d status 0x%x", dlci, cr, rls->status);
1592
1593 if (!cr)
1594 return 0;
1595
1596 /* We should probably do something with this information here. But
1597 * for now it's sufficient just to reply -- Bluetooth 1.1 says it's
1598 * mandatory to recognise and respond to RLS */
1599
1600 rfcomm_send_rls(s, 0, dlci, rls->status);
1601
1602 return 0;
1603 }
1604
rfcomm_recv_msc(struct rfcomm_session * s,int cr,struct sk_buff * skb)1605 static int rfcomm_recv_msc(struct rfcomm_session *s, int cr, struct sk_buff *skb)
1606 {
1607 struct rfcomm_msc *msc = (void *) skb->data;
1608 struct rfcomm_dlc *d;
1609 u8 dlci = __get_dlci(msc->dlci);
1610
1611 BT_DBG("dlci %d cr %d v24 0x%x", dlci, cr, msc->v24_sig);
1612
1613 d = rfcomm_dlc_get(s, dlci);
1614 if (!d)
1615 return 0;
1616
1617 if (cr) {
1618 if (msc->v24_sig & RFCOMM_V24_FC && !d->cfc)
1619 set_bit(RFCOMM_TX_THROTTLED, &d->flags);
1620 else
1621 clear_bit(RFCOMM_TX_THROTTLED, &d->flags);
1622
1623 rfcomm_dlc_lock(d);
1624
1625 d->remote_v24_sig = msc->v24_sig;
1626
1627 if (d->modem_status)
1628 d->modem_status(d, msc->v24_sig);
1629
1630 rfcomm_dlc_unlock(d);
1631
1632 rfcomm_send_msc(s, 0, dlci, msc->v24_sig);
1633
1634 d->mscex |= RFCOMM_MSCEX_RX;
1635 } else
1636 d->mscex |= RFCOMM_MSCEX_TX;
1637
1638 return 0;
1639 }
1640
rfcomm_recv_mcc(struct rfcomm_session * s,struct sk_buff * skb)1641 static int rfcomm_recv_mcc(struct rfcomm_session *s, struct sk_buff *skb)
1642 {
1643 struct rfcomm_mcc *mcc = (void *) skb->data;
1644 u8 type, cr, len;
1645
1646 cr = __test_cr(mcc->type);
1647 type = __get_mcc_type(mcc->type);
1648 len = __get_mcc_len(mcc->len);
1649
1650 BT_DBG("%p type 0x%x cr %d", s, type, cr);
1651
1652 skb_pull(skb, 2);
1653
1654 switch (type) {
1655 case RFCOMM_PN:
1656 rfcomm_recv_pn(s, cr, skb);
1657 break;
1658
1659 case RFCOMM_RPN:
1660 rfcomm_recv_rpn(s, cr, len, skb);
1661 break;
1662
1663 case RFCOMM_RLS:
1664 rfcomm_recv_rls(s, cr, skb);
1665 break;
1666
1667 case RFCOMM_MSC:
1668 rfcomm_recv_msc(s, cr, skb);
1669 break;
1670
1671 case RFCOMM_FCOFF:
1672 if (cr) {
1673 set_bit(RFCOMM_TX_THROTTLED, &s->flags);
1674 rfcomm_send_fcoff(s, 0);
1675 }
1676 break;
1677
1678 case RFCOMM_FCON:
1679 if (cr) {
1680 clear_bit(RFCOMM_TX_THROTTLED, &s->flags);
1681 rfcomm_send_fcon(s, 0);
1682 }
1683 break;
1684
1685 case RFCOMM_TEST:
1686 if (cr)
1687 rfcomm_send_test(s, 0, skb->data, skb->len);
1688 break;
1689
1690 case RFCOMM_NSC:
1691 break;
1692
1693 default:
1694 BT_ERR("Unknown control type 0x%02x", type);
1695 rfcomm_send_nsc(s, cr, type);
1696 break;
1697 }
1698 return 0;
1699 }
1700
rfcomm_recv_data(struct rfcomm_session * s,u8 dlci,int pf,struct sk_buff * skb)1701 static int rfcomm_recv_data(struct rfcomm_session *s, u8 dlci, int pf, struct sk_buff *skb)
1702 {
1703 struct rfcomm_dlc *d;
1704
1705 BT_DBG("session %p state %ld dlci %d pf %d", s, s->state, dlci, pf);
1706
1707 d = rfcomm_dlc_get(s, dlci);
1708 if (!d) {
1709 rfcomm_send_dm(s, dlci);
1710 goto drop;
1711 }
1712
1713 if (pf && d->cfc) {
1714 u8 credits = *(u8 *) skb->data; skb_pull(skb, 1);
1715
1716 d->tx_credits += credits;
1717 if (d->tx_credits)
1718 clear_bit(RFCOMM_TX_THROTTLED, &d->flags);
1719 }
1720
1721 if (skb->len && d->state == BT_CONNECTED) {
1722 rfcomm_dlc_lock(d);
1723 d->rx_credits--;
1724 d->data_ready(d, skb);
1725 rfcomm_dlc_unlock(d);
1726 return 0;
1727 }
1728
1729 drop:
1730 kfree_skb(skb);
1731 return 0;
1732 }
1733
rfcomm_recv_frame(struct rfcomm_session * s,struct sk_buff * skb)1734 static struct rfcomm_session *rfcomm_recv_frame(struct rfcomm_session *s,
1735 struct sk_buff *skb)
1736 {
1737 struct rfcomm_hdr *hdr = (void *) skb->data;
1738 u8 type, dlci, fcs;
1739
1740 if (!s) {
1741 /* no session, so free socket data */
1742 kfree_skb(skb);
1743 return s;
1744 }
1745
1746 dlci = __get_dlci(hdr->addr);
1747 type = __get_type(hdr->ctrl);
1748
1749 /* Trim FCS */
1750 skb->len--; skb->tail--;
1751 fcs = *(u8 *)skb_tail_pointer(skb);
1752
1753 if (__check_fcs(skb->data, type, fcs)) {
1754 BT_ERR("bad checksum in packet");
1755 kfree_skb(skb);
1756 return s;
1757 }
1758
1759 if (__test_ea(hdr->len))
1760 skb_pull(skb, 3);
1761 else
1762 skb_pull(skb, 4);
1763
1764 switch (type) {
1765 case RFCOMM_SABM:
1766 if (__test_pf(hdr->ctrl))
1767 rfcomm_recv_sabm(s, dlci);
1768 break;
1769
1770 case RFCOMM_DISC:
1771 if (__test_pf(hdr->ctrl))
1772 s = rfcomm_recv_disc(s, dlci);
1773 break;
1774
1775 case RFCOMM_UA:
1776 if (__test_pf(hdr->ctrl))
1777 s = rfcomm_recv_ua(s, dlci);
1778 break;
1779
1780 case RFCOMM_DM:
1781 s = rfcomm_recv_dm(s, dlci);
1782 break;
1783
1784 case RFCOMM_UIH:
1785 if (dlci) {
1786 rfcomm_recv_data(s, dlci, __test_pf(hdr->ctrl), skb);
1787 return s;
1788 }
1789 rfcomm_recv_mcc(s, skb);
1790 break;
1791
1792 default:
1793 BT_ERR("Unknown packet type 0x%02x", type);
1794 break;
1795 }
1796 kfree_skb(skb);
1797 return s;
1798 }
1799
1800 /* ---- Connection and data processing ---- */
1801
rfcomm_process_connect(struct rfcomm_session * s)1802 static void rfcomm_process_connect(struct rfcomm_session *s)
1803 {
1804 struct rfcomm_dlc *d, *n;
1805
1806 BT_DBG("session %p state %ld", s, s->state);
1807
1808 list_for_each_entry_safe(d, n, &s->dlcs, list) {
1809 if (d->state == BT_CONFIG) {
1810 d->mtu = s->mtu;
1811 if (rfcomm_check_security(d)) {
1812 rfcomm_send_pn(s, 1, d);
1813 } else {
1814 set_bit(RFCOMM_AUTH_PENDING, &d->flags);
1815 rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1816 }
1817 }
1818 }
1819 }
1820
1821 /* Send data queued for the DLC.
1822 * Return number of frames left in the queue.
1823 */
rfcomm_process_tx(struct rfcomm_dlc * d)1824 static int rfcomm_process_tx(struct rfcomm_dlc *d)
1825 {
1826 struct sk_buff *skb;
1827 int err;
1828
1829 BT_DBG("dlc %p state %ld cfc %d rx_credits %d tx_credits %d",
1830 d, d->state, d->cfc, d->rx_credits, d->tx_credits);
1831
1832 /* Send pending MSC */
1833 if (test_and_clear_bit(RFCOMM_MSC_PENDING, &d->flags))
1834 rfcomm_send_msc(d->session, 1, d->dlci, d->v24_sig);
1835
1836 if (d->cfc) {
1837 /* CFC enabled.
1838 * Give them some credits */
1839 if (!test_bit(RFCOMM_RX_THROTTLED, &d->flags) &&
1840 d->rx_credits <= (d->cfc >> 2)) {
1841 rfcomm_send_credits(d->session, d->addr, d->cfc - d->rx_credits);
1842 d->rx_credits = d->cfc;
1843 }
1844 } else {
1845 /* CFC disabled.
1846 * Give ourselves some credits */
1847 d->tx_credits = 5;
1848 }
1849
1850 if (test_bit(RFCOMM_TX_THROTTLED, &d->flags))
1851 return skb_queue_len(&d->tx_queue);
1852
1853 while (d->tx_credits && (skb = skb_dequeue(&d->tx_queue))) {
1854 err = rfcomm_send_frame(d->session, skb->data, skb->len);
1855 if (err < 0) {
1856 skb_queue_head(&d->tx_queue, skb);
1857 break;
1858 }
1859 kfree_skb(skb);
1860 d->tx_credits--;
1861 }
1862
1863 if (d->cfc && !d->tx_credits) {
1864 /* We're out of TX credits.
1865 * Set TX_THROTTLED flag to avoid unnesary wakeups by dlc_send. */
1866 set_bit(RFCOMM_TX_THROTTLED, &d->flags);
1867 }
1868
1869 return skb_queue_len(&d->tx_queue);
1870 }
1871
rfcomm_process_dlcs(struct rfcomm_session * s)1872 static void rfcomm_process_dlcs(struct rfcomm_session *s)
1873 {
1874 struct rfcomm_dlc *d, *n;
1875
1876 BT_DBG("session %p state %ld", s, s->state);
1877
1878 list_for_each_entry_safe(d, n, &s->dlcs, list) {
1879 if (test_bit(RFCOMM_TIMED_OUT, &d->flags)) {
1880 __rfcomm_dlc_close(d, ETIMEDOUT);
1881 continue;
1882 }
1883
1884 if (test_bit(RFCOMM_ENC_DROP, &d->flags)) {
1885 __rfcomm_dlc_close(d, ECONNREFUSED);
1886 continue;
1887 }
1888
1889 if (test_and_clear_bit(RFCOMM_AUTH_ACCEPT, &d->flags)) {
1890 rfcomm_dlc_clear_timer(d);
1891 if (d->out) {
1892 rfcomm_send_pn(s, 1, d);
1893 rfcomm_dlc_set_timer(d, RFCOMM_CONN_TIMEOUT);
1894 } else {
1895 if (d->defer_setup) {
1896 set_bit(RFCOMM_DEFER_SETUP, &d->flags);
1897 rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1898
1899 rfcomm_dlc_lock(d);
1900 d->state = BT_CONNECT2;
1901 d->state_change(d, 0);
1902 rfcomm_dlc_unlock(d);
1903 } else
1904 rfcomm_dlc_accept(d);
1905 }
1906 continue;
1907 } else if (test_and_clear_bit(RFCOMM_AUTH_REJECT, &d->flags)) {
1908 rfcomm_dlc_clear_timer(d);
1909 if (!d->out)
1910 rfcomm_send_dm(s, d->dlci);
1911 else
1912 d->state = BT_CLOSED;
1913 __rfcomm_dlc_close(d, ECONNREFUSED);
1914 continue;
1915 }
1916
1917 if (test_bit(RFCOMM_SEC_PENDING, &d->flags))
1918 continue;
1919
1920 if (test_bit(RFCOMM_TX_THROTTLED, &s->flags))
1921 continue;
1922
1923 if ((d->state == BT_CONNECTED || d->state == BT_DISCONN) &&
1924 d->mscex == RFCOMM_MSCEX_OK)
1925 rfcomm_process_tx(d);
1926 }
1927 }
1928
rfcomm_process_rx(struct rfcomm_session * s)1929 static struct rfcomm_session *rfcomm_process_rx(struct rfcomm_session *s)
1930 {
1931 struct socket *sock = s->sock;
1932 struct sock *sk = sock->sk;
1933 struct sk_buff *skb;
1934
1935 BT_DBG("session %p state %ld qlen %d", s, s->state, skb_queue_len(&sk->sk_receive_queue));
1936
1937 /* Get data directly from socket receive queue without copying it. */
1938 while ((skb = skb_dequeue(&sk->sk_receive_queue))) {
1939 skb_orphan(skb);
1940 if (!skb_linearize(skb)) {
1941 s = rfcomm_recv_frame(s, skb);
1942 if (!s)
1943 break;
1944 } else {
1945 kfree_skb(skb);
1946 }
1947 }
1948
1949 if (s && (sk->sk_state == BT_CLOSED))
1950 s = rfcomm_session_close(s, sk->sk_err);
1951
1952 return s;
1953 }
1954
rfcomm_accept_connection(struct rfcomm_session * s)1955 static void rfcomm_accept_connection(struct rfcomm_session *s)
1956 {
1957 struct socket *sock = s->sock, *nsock;
1958 int err;
1959
1960 /* Fast check for a new connection.
1961 * Avoids unnesesary socket allocations. */
1962 if (list_empty(&bt_sk(sock->sk)->accept_q))
1963 return;
1964
1965 BT_DBG("session %p", s);
1966
1967 err = kernel_accept(sock, &nsock, O_NONBLOCK);
1968 if (err < 0)
1969 return;
1970
1971 /* Set our callbacks */
1972 nsock->sk->sk_data_ready = rfcomm_l2data_ready;
1973 nsock->sk->sk_state_change = rfcomm_l2state_change;
1974
1975 s = rfcomm_session_add(nsock, BT_OPEN);
1976 if (s) {
1977 /* We should adjust MTU on incoming sessions.
1978 * L2CAP MTU minus UIH header and FCS. */
1979 s->mtu = min(l2cap_pi(nsock->sk)->chan->omtu,
1980 l2cap_pi(nsock->sk)->chan->imtu) - 5;
1981
1982 rfcomm_schedule();
1983 } else
1984 sock_release(nsock);
1985 }
1986
rfcomm_check_connection(struct rfcomm_session * s)1987 static struct rfcomm_session *rfcomm_check_connection(struct rfcomm_session *s)
1988 {
1989 struct sock *sk = s->sock->sk;
1990
1991 BT_DBG("%p state %ld", s, s->state);
1992
1993 switch (sk->sk_state) {
1994 case BT_CONNECTED:
1995 s->state = BT_CONNECT;
1996
1997 /* We can adjust MTU on outgoing sessions.
1998 * L2CAP MTU minus UIH header and FCS. */
1999 s->mtu = min(l2cap_pi(sk)->chan->omtu, l2cap_pi(sk)->chan->imtu) - 5;
2000
2001 rfcomm_send_sabm(s, 0);
2002 break;
2003
2004 case BT_CLOSED:
2005 s = rfcomm_session_close(s, sk->sk_err);
2006 break;
2007 }
2008 return s;
2009 }
2010
rfcomm_process_sessions(void)2011 static void rfcomm_process_sessions(void)
2012 {
2013 struct rfcomm_session *s, *n;
2014
2015 rfcomm_lock();
2016
2017 list_for_each_entry_safe(s, n, &session_list, list) {
2018 if (test_and_clear_bit(RFCOMM_TIMED_OUT, &s->flags)) {
2019 s->state = BT_DISCONN;
2020 rfcomm_send_disc(s, 0);
2021 continue;
2022 }
2023
2024 switch (s->state) {
2025 case BT_LISTEN:
2026 rfcomm_accept_connection(s);
2027 continue;
2028
2029 case BT_BOUND:
2030 s = rfcomm_check_connection(s);
2031 break;
2032
2033 default:
2034 s = rfcomm_process_rx(s);
2035 break;
2036 }
2037
2038 if (s)
2039 rfcomm_process_dlcs(s);
2040 }
2041
2042 rfcomm_unlock();
2043 }
2044
rfcomm_add_listener(bdaddr_t * ba)2045 static int rfcomm_add_listener(bdaddr_t *ba)
2046 {
2047 struct sockaddr_l2 addr;
2048 struct socket *sock;
2049 struct sock *sk;
2050 struct rfcomm_session *s;
2051 int err = 0;
2052
2053 /* Create socket */
2054 err = rfcomm_l2sock_create(&sock);
2055 if (err < 0) {
2056 BT_ERR("Create socket failed %d", err);
2057 return err;
2058 }
2059
2060 /* Bind socket */
2061 bacpy(&addr.l2_bdaddr, ba);
2062 addr.l2_family = AF_BLUETOOTH;
2063 addr.l2_psm = cpu_to_le16(L2CAP_PSM_RFCOMM);
2064 addr.l2_cid = 0;
2065 addr.l2_bdaddr_type = BDADDR_BREDR;
2066 err = kernel_bind(sock, (struct sockaddr *) &addr, sizeof(addr));
2067 if (err < 0) {
2068 BT_ERR("Bind failed %d", err);
2069 goto failed;
2070 }
2071
2072 /* Set L2CAP options */
2073 sk = sock->sk;
2074 lock_sock(sk);
2075 /* Set MTU to 0 so L2CAP can auto select the MTU */
2076 l2cap_pi(sk)->chan->imtu = 0;
2077 release_sock(sk);
2078
2079 /* Start listening on the socket */
2080 err = kernel_listen(sock, 10);
2081 if (err) {
2082 BT_ERR("Listen failed %d", err);
2083 goto failed;
2084 }
2085
2086 /* Add listening session */
2087 s = rfcomm_session_add(sock, BT_LISTEN);
2088 if (!s) {
2089 err = -ENOMEM;
2090 goto failed;
2091 }
2092
2093 return 0;
2094 failed:
2095 sock_release(sock);
2096 return err;
2097 }
2098
rfcomm_kill_listener(void)2099 static void rfcomm_kill_listener(void)
2100 {
2101 struct rfcomm_session *s, *n;
2102
2103 BT_DBG("");
2104
2105 list_for_each_entry_safe(s, n, &session_list, list)
2106 rfcomm_session_del(s);
2107 }
2108
rfcomm_run(void * unused)2109 static int rfcomm_run(void *unused)
2110 {
2111 DEFINE_WAIT_FUNC(wait, woken_wake_function);
2112 BT_DBG("");
2113
2114 set_user_nice(current, -10);
2115
2116 rfcomm_add_listener(BDADDR_ANY);
2117
2118 add_wait_queue(&rfcomm_wq, &wait);
2119 while (!kthread_should_stop()) {
2120
2121 /* Process stuff */
2122 rfcomm_process_sessions();
2123
2124 wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
2125 }
2126 remove_wait_queue(&rfcomm_wq, &wait);
2127
2128 rfcomm_kill_listener();
2129
2130 return 0;
2131 }
2132
rfcomm_security_cfm(struct hci_conn * conn,u8 status,u8 encrypt)2133 static void rfcomm_security_cfm(struct hci_conn *conn, u8 status, u8 encrypt)
2134 {
2135 struct rfcomm_session *s;
2136 struct rfcomm_dlc *d, *n;
2137
2138 BT_DBG("conn %p status 0x%02x encrypt 0x%02x", conn, status, encrypt);
2139
2140 s = rfcomm_session_get(&conn->hdev->bdaddr, &conn->dst);
2141 if (!s)
2142 return;
2143
2144 list_for_each_entry_safe(d, n, &s->dlcs, list) {
2145 if (test_and_clear_bit(RFCOMM_SEC_PENDING, &d->flags)) {
2146 rfcomm_dlc_clear_timer(d);
2147 if (status || encrypt == 0x00) {
2148 set_bit(RFCOMM_ENC_DROP, &d->flags);
2149 continue;
2150 }
2151 }
2152
2153 if (d->state == BT_CONNECTED && !status && encrypt == 0x00) {
2154 if (d->sec_level == BT_SECURITY_MEDIUM) {
2155 set_bit(RFCOMM_SEC_PENDING, &d->flags);
2156 rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
2157 continue;
2158 } else if (d->sec_level == BT_SECURITY_HIGH ||
2159 d->sec_level == BT_SECURITY_FIPS) {
2160 set_bit(RFCOMM_ENC_DROP, &d->flags);
2161 continue;
2162 }
2163 }
2164
2165 if (!test_and_clear_bit(RFCOMM_AUTH_PENDING, &d->flags))
2166 continue;
2167
2168 if (!status && hci_conn_check_secure(conn, d->sec_level))
2169 set_bit(RFCOMM_AUTH_ACCEPT, &d->flags);
2170 else
2171 set_bit(RFCOMM_AUTH_REJECT, &d->flags);
2172 }
2173
2174 rfcomm_schedule();
2175 }
2176
2177 static struct hci_cb rfcomm_cb = {
2178 .name = "RFCOMM",
2179 .security_cfm = rfcomm_security_cfm
2180 };
2181
rfcomm_dlc_debugfs_show(struct seq_file * f,void * x)2182 static int rfcomm_dlc_debugfs_show(struct seq_file *f, void *x)
2183 {
2184 struct rfcomm_session *s;
2185
2186 rfcomm_lock();
2187
2188 list_for_each_entry(s, &session_list, list) {
2189 struct l2cap_chan *chan = l2cap_pi(s->sock->sk)->chan;
2190 struct rfcomm_dlc *d;
2191 list_for_each_entry(d, &s->dlcs, list) {
2192 seq_printf(f, "%pMR %pMR %ld %d %d %d %d\n",
2193 &chan->src, &chan->dst,
2194 d->state, d->dlci, d->mtu,
2195 d->rx_credits, d->tx_credits);
2196 }
2197 }
2198
2199 rfcomm_unlock();
2200
2201 return 0;
2202 }
2203
2204 DEFINE_SHOW_ATTRIBUTE(rfcomm_dlc_debugfs);
2205
2206 static struct dentry *rfcomm_dlc_debugfs;
2207
2208 /* ---- Initialization ---- */
rfcomm_init(void)2209 static int __init rfcomm_init(void)
2210 {
2211 int err;
2212
2213 hci_register_cb(&rfcomm_cb);
2214
2215 rfcomm_thread = kthread_run(rfcomm_run, NULL, "krfcommd");
2216 if (IS_ERR(rfcomm_thread)) {
2217 err = PTR_ERR(rfcomm_thread);
2218 goto unregister;
2219 }
2220
2221 err = rfcomm_init_ttys();
2222 if (err < 0)
2223 goto stop;
2224
2225 err = rfcomm_init_sockets();
2226 if (err < 0)
2227 goto cleanup;
2228
2229 BT_INFO("RFCOMM ver %s", VERSION);
2230
2231 if (IS_ERR_OR_NULL(bt_debugfs))
2232 return 0;
2233
2234 rfcomm_dlc_debugfs = debugfs_create_file("rfcomm_dlc", 0444,
2235 bt_debugfs, NULL,
2236 &rfcomm_dlc_debugfs_fops);
2237
2238 return 0;
2239
2240 cleanup:
2241 rfcomm_cleanup_ttys();
2242
2243 stop:
2244 kthread_stop(rfcomm_thread);
2245
2246 unregister:
2247 hci_unregister_cb(&rfcomm_cb);
2248
2249 return err;
2250 }
2251
rfcomm_exit(void)2252 static void __exit rfcomm_exit(void)
2253 {
2254 debugfs_remove(rfcomm_dlc_debugfs);
2255
2256 hci_unregister_cb(&rfcomm_cb);
2257
2258 kthread_stop(rfcomm_thread);
2259
2260 rfcomm_cleanup_ttys();
2261
2262 rfcomm_cleanup_sockets();
2263 }
2264
2265 module_init(rfcomm_init);
2266 module_exit(rfcomm_exit);
2267
2268 module_param(disable_cfc, bool, 0644);
2269 MODULE_PARM_DESC(disable_cfc, "Disable credit based flow control");
2270
2271 module_param(channel_mtu, int, 0644);
2272 MODULE_PARM_DESC(channel_mtu, "Default MTU for the RFCOMM channel");
2273
2274 module_param(l2cap_ertm, bool, 0644);
2275 MODULE_PARM_DESC(l2cap_ertm, "Use L2CAP ERTM mode for connection");
2276
2277 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
2278 MODULE_DESCRIPTION("Bluetooth RFCOMM ver " VERSION);
2279 MODULE_VERSION(VERSION);
2280 MODULE_LICENSE("GPL");
2281 MODULE_ALIAS("bt-proto-3");
2282
