1 /*
2    BlueZ - Bluetooth protocol stack for Linux
3    Copyright (C) 2000-2001 Qualcomm Incorporated
4    Copyright (C) 2009-2010 Gustavo F. Padovan <gustavo@padovan.org>
5    Copyright (C) 2010 Google Inc.
6 
7    Written 2000,2001 by Maxim Krasnyansky <maxk@qualcomm.com>
8 
9    This program is free software; you can redistribute it and/or modify
10    it under the terms of the GNU General Public License version 2 as
11    published by the Free Software Foundation;
12 
13    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
14    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
16    IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
17    CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
18    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
19    ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
20    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
21 
22    ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
23    COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
24    SOFTWARE IS DISCLAIMED.
25 */
26 
27 #ifndef __L2CAP_H
28 #define __L2CAP_H
29 
30 /* L2CAP defaults */
31 #define L2CAP_DEFAULT_MTU		672
32 #define L2CAP_DEFAULT_MIN_MTU		48
33 #define L2CAP_DEFAULT_FLUSH_TO		0xffff
34 #define L2CAP_DEFAULT_TX_WINDOW		63
35 #define L2CAP_DEFAULT_MAX_TX		3
36 #define L2CAP_DEFAULT_RETRANS_TO	2000    /* 2 seconds */
37 #define L2CAP_DEFAULT_MONITOR_TO	12000   /* 12 seconds */
38 #define L2CAP_DEFAULT_MAX_PDU_SIZE	1009    /* Sized for 3-DH5 packet */
39 #define L2CAP_DEFAULT_ACK_TO		200
40 #define L2CAP_LOCAL_BUSY_TRIES		12
41 #define L2CAP_LE_DEFAULT_MTU		23
42 
43 #define L2CAP_CONN_TIMEOUT	(40000) /* 40 seconds */
44 #define L2CAP_INFO_TIMEOUT	(4000)  /*  4 seconds */
45 
46 /* L2CAP socket address */
47 struct sockaddr_l2 {
48 	sa_family_t	l2_family;
49 	__le16		l2_psm;
50 	bdaddr_t	l2_bdaddr;
51 	__le16		l2_cid;
52 };
53 
54 /* L2CAP socket options */
55 #define L2CAP_OPTIONS	0x01
56 struct l2cap_options {
57 	__u16 omtu;
58 	__u16 imtu;
59 	__u16 flush_to;
60 	__u8  mode;
61 	__u8  fcs;
62 	__u8  max_tx;
63 	__u16 txwin_size;
64 };
65 
66 #define L2CAP_CONNINFO	0x02
67 struct l2cap_conninfo {
68 	__u16 hci_handle;
69 	__u8  dev_class[3];
70 };
71 
72 #define L2CAP_LM	0x03
73 #define L2CAP_LM_MASTER		0x0001
74 #define L2CAP_LM_AUTH		0x0002
75 #define L2CAP_LM_ENCRYPT	0x0004
76 #define L2CAP_LM_TRUSTED	0x0008
77 #define L2CAP_LM_RELIABLE	0x0010
78 #define L2CAP_LM_SECURE		0x0020
79 
80 /* L2CAP command codes */
81 #define L2CAP_COMMAND_REJ	0x01
82 #define L2CAP_CONN_REQ		0x02
83 #define L2CAP_CONN_RSP		0x03
84 #define L2CAP_CONF_REQ		0x04
85 #define L2CAP_CONF_RSP		0x05
86 #define L2CAP_DISCONN_REQ	0x06
87 #define L2CAP_DISCONN_RSP	0x07
88 #define L2CAP_ECHO_REQ		0x08
89 #define L2CAP_ECHO_RSP		0x09
90 #define L2CAP_INFO_REQ		0x0a
91 #define L2CAP_INFO_RSP		0x0b
92 #define L2CAP_CONN_PARAM_UPDATE_REQ	0x12
93 #define L2CAP_CONN_PARAM_UPDATE_RSP	0x13
94 
95 /* L2CAP feature mask */
96 #define L2CAP_FEAT_FLOWCTL	0x00000001
97 #define L2CAP_FEAT_RETRANS	0x00000002
98 #define L2CAP_FEAT_ERTM		0x00000008
99 #define L2CAP_FEAT_STREAMING	0x00000010
100 #define L2CAP_FEAT_FCS		0x00000020
101 #define L2CAP_FEAT_FIXED_CHAN	0x00000080
102 
103 /* L2CAP checksum option */
104 #define L2CAP_FCS_NONE		0x00
105 #define L2CAP_FCS_CRC16		0x01
106 
107 /* L2CAP Control Field bit masks */
108 #define L2CAP_CTRL_SAR               0xC000
109 #define L2CAP_CTRL_REQSEQ            0x3F00
110 #define L2CAP_CTRL_TXSEQ             0x007E
111 #define L2CAP_CTRL_RETRANS           0x0080
112 #define L2CAP_CTRL_FINAL             0x0080
113 #define L2CAP_CTRL_POLL              0x0010
114 #define L2CAP_CTRL_SUPERVISE         0x000C
115 #define L2CAP_CTRL_FRAME_TYPE        0x0001 /* I- or S-Frame */
116 
117 #define L2CAP_CTRL_TXSEQ_SHIFT      1
118 #define L2CAP_CTRL_REQSEQ_SHIFT     8
119 #define L2CAP_CTRL_SAR_SHIFT       14
120 
121 /* L2CAP Supervisory Function */
122 #define L2CAP_SUPER_RCV_READY           0x0000
123 #define L2CAP_SUPER_REJECT              0x0004
124 #define L2CAP_SUPER_RCV_NOT_READY       0x0008
125 #define L2CAP_SUPER_SELECT_REJECT       0x000C
126 
127 /* L2CAP Segmentation and Reassembly */
128 #define L2CAP_SDU_UNSEGMENTED       0x0000
129 #define L2CAP_SDU_START             0x4000
130 #define L2CAP_SDU_END               0x8000
131 #define L2CAP_SDU_CONTINUE          0xC000
132 
133 /* L2CAP structures */
134 struct l2cap_hdr {
135 	__le16     len;
136 	__le16     cid;
137 } __packed;
138 #define L2CAP_HDR_SIZE		4
139 
140 struct l2cap_cmd_hdr {
141 	__u8       code;
142 	__u8       ident;
143 	__le16     len;
144 } __packed;
145 #define L2CAP_CMD_HDR_SIZE	4
146 
147 struct l2cap_cmd_rej {
148 	__le16     reason;
149 } __packed;
150 
151 struct l2cap_conn_req {
152 	__le16     psm;
153 	__le16     scid;
154 } __packed;
155 
156 struct l2cap_conn_rsp {
157 	__le16     dcid;
158 	__le16     scid;
159 	__le16     result;
160 	__le16     status;
161 } __packed;
162 
163 /* channel indentifier */
164 #define L2CAP_CID_SIGNALING	0x0001
165 #define L2CAP_CID_CONN_LESS	0x0002
166 #define L2CAP_CID_LE_DATA	0x0004
167 #define L2CAP_CID_LE_SIGNALING	0x0005
168 #define L2CAP_CID_SMP		0x0006
169 #define L2CAP_CID_DYN_START	0x0040
170 #define L2CAP_CID_DYN_END	0xffff
171 
172 /* connect result */
173 #define L2CAP_CR_SUCCESS	0x0000
174 #define L2CAP_CR_PEND		0x0001
175 #define L2CAP_CR_BAD_PSM	0x0002
176 #define L2CAP_CR_SEC_BLOCK	0x0003
177 #define L2CAP_CR_NO_MEM		0x0004
178 
179 /* connect status */
180 #define L2CAP_CS_NO_INFO	0x0000
181 #define L2CAP_CS_AUTHEN_PEND	0x0001
182 #define L2CAP_CS_AUTHOR_PEND	0x0002
183 
184 struct l2cap_conf_req {
185 	__le16     dcid;
186 	__le16     flags;
187 	__u8       data[0];
188 } __packed;
189 
190 struct l2cap_conf_rsp {
191 	__le16     scid;
192 	__le16     flags;
193 	__le16     result;
194 	__u8       data[0];
195 } __packed;
196 
197 #define L2CAP_CONF_SUCCESS	0x0000
198 #define L2CAP_CONF_UNACCEPT	0x0001
199 #define L2CAP_CONF_REJECT	0x0002
200 #define L2CAP_CONF_UNKNOWN	0x0003
201 
202 struct l2cap_conf_opt {
203 	__u8       type;
204 	__u8       len;
205 	__u8       val[0];
206 } __packed;
207 #define L2CAP_CONF_OPT_SIZE	2
208 
209 #define L2CAP_CONF_HINT		0x80
210 #define L2CAP_CONF_MASK		0x7f
211 
212 #define L2CAP_CONF_MTU		0x01
213 #define L2CAP_CONF_FLUSH_TO	0x02
214 #define L2CAP_CONF_QOS		0x03
215 #define L2CAP_CONF_RFC		0x04
216 #define L2CAP_CONF_FCS		0x05
217 
218 #define L2CAP_CONF_MAX_SIZE	22
219 
220 struct l2cap_conf_rfc {
221 	__u8       mode;
222 	__u8       txwin_size;
223 	__u8       max_transmit;
224 	__le16     retrans_timeout;
225 	__le16     monitor_timeout;
226 	__le16     max_pdu_size;
227 } __packed;
228 
229 #define L2CAP_MODE_BASIC	0x00
230 #define L2CAP_MODE_RETRANS	0x01
231 #define L2CAP_MODE_FLOWCTL	0x02
232 #define L2CAP_MODE_ERTM		0x03
233 #define L2CAP_MODE_STREAMING	0x04
234 
235 struct l2cap_disconn_req {
236 	__le16     dcid;
237 	__le16     scid;
238 } __packed;
239 
240 struct l2cap_disconn_rsp {
241 	__le16     dcid;
242 	__le16     scid;
243 } __packed;
244 
245 struct l2cap_info_req {
246 	__le16      type;
247 } __packed;
248 
249 struct l2cap_info_rsp {
250 	__le16      type;
251 	__le16      result;
252 	__u8        data[0];
253 } __packed;
254 
255 /* info type */
256 #define L2CAP_IT_CL_MTU     0x0001
257 #define L2CAP_IT_FEAT_MASK  0x0002
258 #define L2CAP_IT_FIXED_CHAN 0x0003
259 
260 /* info result */
261 #define L2CAP_IR_SUCCESS    0x0000
262 #define L2CAP_IR_NOTSUPP    0x0001
263 
264 struct l2cap_conn_param_update_req {
265 	__le16      min;
266 	__le16      max;
267 	__le16      latency;
268 	__le16      to_multiplier;
269 } __packed;
270 
271 struct l2cap_conn_param_update_rsp {
272 	__le16      result;
273 } __packed;
274 
275 /* Connection Parameters result */
276 #define L2CAP_CONN_PARAM_ACCEPTED	0x0000
277 #define L2CAP_CONN_PARAM_REJECTED	0x0001
278 
279 /* ----- L2CAP connections ----- */
280 struct l2cap_chan_list {
281 	struct sock	*head;
282 	rwlock_t	lock;
283 	long		num;
284 };
285 
286 struct l2cap_conn {
287 	struct hci_conn	*hcon;
288 
289 	bdaddr_t	*dst;
290 	bdaddr_t	*src;
291 
292 	unsigned int	mtu;
293 
294 	__u32		feat_mask;
295 
296 	__u8		info_state;
297 	__u8		info_ident;
298 
299 	struct timer_list info_timer;
300 
301 	spinlock_t	lock;
302 
303 	struct sk_buff *rx_skb;
304 	__u32		rx_len;
305 	__u8		rx_ident;
306 	__u8		tx_ident;
307 
308 	__u8		disc_reason;
309 
310 	struct l2cap_chan_list chan_list;
311 };
312 
313 struct sock_del_list {
314 	struct sock *sk;
315 	struct list_head list;
316 };
317 
318 #define L2CAP_INFO_CL_MTU_REQ_SENT	0x01
319 #define L2CAP_INFO_FEAT_MASK_REQ_SENT	0x04
320 #define L2CAP_INFO_FEAT_MASK_REQ_DONE	0x08
321 
322 /* ----- L2CAP channel and socket info ----- */
323 #define l2cap_pi(sk) ((struct l2cap_pinfo *) sk)
324 #define TX_QUEUE(sk) (&l2cap_pi(sk)->tx_queue)
325 #define SREJ_QUEUE(sk) (&l2cap_pi(sk)->srej_queue)
326 #define BUSY_QUEUE(sk) (&l2cap_pi(sk)->busy_queue)
327 #define SREJ_LIST(sk) (&l2cap_pi(sk)->srej_l.list)
328 
329 struct srej_list {
330 	__u8	tx_seq;
331 	struct list_head list;
332 };
333 
334 struct l2cap_pinfo {
335 	struct bt_sock	bt;
336 	__le16		psm;
337 	__u16		dcid;
338 	__u16		scid;
339 
340 	__u16		imtu;
341 	__u16		omtu;
342 	__u16		flush_to;
343 	__u8		mode;
344 	__u8		num_conf_req;
345 	__u8		num_conf_rsp;
346 
347 	__u8		fcs;
348 	__u8		sec_level;
349 	__u8		role_switch;
350 	__u8		force_reliable;
351 	__u8		flushable;
352 
353 	__u8		conf_req[64];
354 	__u8		conf_len;
355 	__u8		conf_state;
356 	__u16		conn_state;
357 
358 	__u8		next_tx_seq;
359 	__u8		expected_ack_seq;
360 	__u8		expected_tx_seq;
361 	__u8		buffer_seq;
362 	__u8		buffer_seq_srej;
363 	__u8		srej_save_reqseq;
364 	__u8		frames_sent;
365 	__u8		unacked_frames;
366 	__u8		retry_count;
367 	__u8		num_acked;
368 	__u16		sdu_len;
369 	__u16		partial_sdu_len;
370 	struct sk_buff	*sdu;
371 
372 	__u8		ident;
373 
374 	__u8		tx_win;
375 	__u8		max_tx;
376 	__u8		remote_tx_win;
377 	__u8		remote_max_tx;
378 	__u16		retrans_timeout;
379 	__u16		monitor_timeout;
380 	__u16		remote_mps;
381 	__u16		mps;
382 
383 	__le16		sport;
384 
385 	struct timer_list	retrans_timer;
386 	struct timer_list	monitor_timer;
387 	struct timer_list	ack_timer;
388 	struct sk_buff_head	tx_queue;
389 	struct sk_buff_head	srej_queue;
390 	struct sk_buff_head	busy_queue;
391 	struct work_struct	busy_work;
392 	struct srej_list	srej_l;
393 	struct l2cap_conn	*conn;
394 	struct sock		*next_c;
395 	struct sock		*prev_c;
396 };
397 
398 #define L2CAP_CONF_REQ_SENT       0x01
399 #define L2CAP_CONF_INPUT_DONE     0x02
400 #define L2CAP_CONF_OUTPUT_DONE    0x04
401 #define L2CAP_CONF_MTU_DONE       0x08
402 #define L2CAP_CONF_MODE_DONE      0x10
403 #define L2CAP_CONF_CONNECT_PEND   0x20
404 #define L2CAP_CONF_NO_FCS_RECV    0x40
405 #define L2CAP_CONF_STATE2_DEVICE  0x80
406 
407 #define L2CAP_CONF_MAX_CONF_REQ 2
408 #define L2CAP_CONF_MAX_CONF_RSP 2
409 
410 #define L2CAP_CONN_SAR_SDU         0x0001
411 #define L2CAP_CONN_SREJ_SENT       0x0002
412 #define L2CAP_CONN_WAIT_F          0x0004
413 #define L2CAP_CONN_SREJ_ACT        0x0008
414 #define L2CAP_CONN_SEND_PBIT       0x0010
415 #define L2CAP_CONN_REMOTE_BUSY     0x0020
416 #define L2CAP_CONN_LOCAL_BUSY      0x0040
417 #define L2CAP_CONN_REJ_ACT         0x0080
418 #define L2CAP_CONN_SEND_FBIT       0x0100
419 #define L2CAP_CONN_RNR_SENT        0x0200
420 #define L2CAP_CONN_SAR_RETRY       0x0400
421 
422 #define __mod_retrans_timer() mod_timer(&l2cap_pi(sk)->retrans_timer, \
423 		jiffies +  msecs_to_jiffies(L2CAP_DEFAULT_RETRANS_TO));
424 #define __mod_monitor_timer() mod_timer(&l2cap_pi(sk)->monitor_timer, \
425 		jiffies + msecs_to_jiffies(L2CAP_DEFAULT_MONITOR_TO));
426 #define __mod_ack_timer() mod_timer(&l2cap_pi(sk)->ack_timer, \
427 		jiffies + msecs_to_jiffies(L2CAP_DEFAULT_ACK_TO));
428 
l2cap_tx_window_full(struct sock * sk)429 static inline int l2cap_tx_window_full(struct sock *sk)
430 {
431 	struct l2cap_pinfo *pi = l2cap_pi(sk);
432 	int sub;
433 
434 	sub = (pi->next_tx_seq - pi->expected_ack_seq) % 64;
435 
436 	if (sub < 0)
437 		sub += 64;
438 
439 	return sub == pi->remote_tx_win;
440 }
441 
442 #define __get_txseq(ctrl)	(((ctrl) & L2CAP_CTRL_TXSEQ) >> 1)
443 #define __get_reqseq(ctrl)	(((ctrl) & L2CAP_CTRL_REQSEQ) >> 8)
444 #define __is_iframe(ctrl)	(!((ctrl) & L2CAP_CTRL_FRAME_TYPE))
445 #define __is_sframe(ctrl)	((ctrl) & L2CAP_CTRL_FRAME_TYPE)
446 #define __is_sar_start(ctrl)	(((ctrl) & L2CAP_CTRL_SAR) == L2CAP_SDU_START)
447 
448 extern int disable_ertm;
449 extern const struct proto_ops l2cap_sock_ops;
450 extern struct bt_sock_list l2cap_sk_list;
451 
452 int l2cap_init_sockets(void);
453 void l2cap_cleanup_sockets(void);
454 
455 u8 l2cap_get_ident(struct l2cap_conn *conn);
456 void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len, void *data);
457 int l2cap_build_conf_req(struct sock *sk, void *data);
458 int __l2cap_wait_ack(struct sock *sk);
459 
460 struct sk_buff *l2cap_create_connless_pdu(struct sock *sk, struct msghdr *msg, size_t len);
461 struct sk_buff *l2cap_create_basic_pdu(struct sock *sk, struct msghdr *msg, size_t len);
462 struct sk_buff *l2cap_create_iframe_pdu(struct sock *sk, struct msghdr *msg, size_t len, u16 control, u16 sdulen);
463 int l2cap_sar_segment_sdu(struct sock *sk, struct msghdr *msg, size_t len);
464 void l2cap_do_send(struct sock *sk, struct sk_buff *skb);
465 void l2cap_streaming_send(struct sock *sk);
466 int l2cap_ertm_send(struct sock *sk);
467 
468 void l2cap_sock_set_timer(struct sock *sk, long timeout);
469 void l2cap_sock_clear_timer(struct sock *sk);
470 void __l2cap_sock_close(struct sock *sk, int reason);
471 void l2cap_sock_kill(struct sock *sk);
472 void l2cap_sock_init(struct sock *sk, struct sock *parent);
473 struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock,
474 							int proto, gfp_t prio);
475 void l2cap_send_disconn_req(struct l2cap_conn *conn, struct sock *sk, int err);
476 void l2cap_chan_del(struct sock *sk, int err);
477 int l2cap_do_connect(struct sock *sk);
478 
479 #endif /* __L2CAP_H */
480