1 /******************************************************************************
2 *
3 * Copyright (C) 1999-2012 Broadcom Corporation
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at:
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 *
17 ******************************************************************************/
18
19 /*****************************************************************************
20 *
21 * This file contains collection of utility functions used the RFCOMM unit
22 *
23 *****************************************************************************/
24
25 #include "bt_common.h"
26 #include "bt_target.h"
27
28 #include "bt_utils.h"
29 #include "btm_api.h"
30 #include "btm_int.h"
31 #include "btu.h"
32 #include "osi/include/osi.h"
33 #include "port_api.h"
34 #include "port_ext.h"
35 #include "port_int.h"
36 #include "rfc_int.h"
37 #include "rfcdefs.h"
38
39 #include <string.h>
40
41 /*******************************************************************************
42 *
43 * Function rfc_calc_fcs
44 *
45 * Description Reversed CRC Table , 8-bit, poly=0x07
46 * (GSM 07.10 TS 101 369 V6.3.0)
47 ******************************************************************************/
48 static const uint8_t rfc_crctable[] = {
49 0x00, 0x91, 0xE3, 0x72, 0x07, 0x96, 0xE4, 0x75, 0x0E, 0x9F, 0xED,
50 0x7C, 0x09, 0x98, 0xEA, 0x7B, 0x1C, 0x8D, 0xFF, 0x6E, 0x1B, 0x8A,
51 0xF8, 0x69, 0x12, 0x83, 0xF1, 0x60, 0x15, 0x84, 0xF6, 0x67, 0x38,
52 0xA9, 0xDB, 0x4A, 0x3F, 0xAE, 0xDC, 0x4D, 0x36, 0xA7, 0xD5, 0x44,
53 0x31, 0xA0, 0xD2, 0x43, 0x24, 0xB5, 0xC7, 0x56, 0x23, 0xB2, 0xC0,
54 0x51, 0x2A, 0xBB, 0xC9, 0x58, 0x2D, 0xBC, 0xCE, 0x5F,
55
56 0x70, 0xE1, 0x93, 0x02, 0x77, 0xE6, 0x94, 0x05, 0x7E, 0xEF, 0x9D,
57 0x0C, 0x79, 0xE8, 0x9A, 0x0B, 0x6C, 0xFD, 0x8F, 0x1E, 0x6B, 0xFA,
58 0x88, 0x19, 0x62, 0xF3, 0x81, 0x10, 0x65, 0xF4, 0x86, 0x17, 0x48,
59 0xD9, 0xAB, 0x3A, 0x4F, 0xDE, 0xAC, 0x3D, 0x46, 0xD7, 0xA5, 0x34,
60 0x41, 0xD0, 0xA2, 0x33, 0x54, 0xC5, 0xB7, 0x26, 0x53, 0xC2, 0xB0,
61 0x21, 0x5A, 0xCB, 0xB9, 0x28, 0x5D, 0xCC, 0xBE, 0x2F,
62
63 0xE0, 0x71, 0x03, 0x92, 0xE7, 0x76, 0x04, 0x95, 0xEE, 0x7F, 0x0D,
64 0x9C, 0xE9, 0x78, 0x0A, 0x9B, 0xFC, 0x6D, 0x1F, 0x8E, 0xFB, 0x6A,
65 0x18, 0x89, 0xF2, 0x63, 0x11, 0x80, 0xF5, 0x64, 0x16, 0x87, 0xD8,
66 0x49, 0x3B, 0xAA, 0xDF, 0x4E, 0x3C, 0xAD, 0xD6, 0x47, 0x35, 0xA4,
67 0xD1, 0x40, 0x32, 0xA3, 0xC4, 0x55, 0x27, 0xB6, 0xC3, 0x52, 0x20,
68 0xB1, 0xCA, 0x5B, 0x29, 0xB8, 0xCD, 0x5C, 0x2E, 0xBF,
69
70 0x90, 0x01, 0x73, 0xE2, 0x97, 0x06, 0x74, 0xE5, 0x9E, 0x0F, 0x7D,
71 0xEC, 0x99, 0x08, 0x7A, 0xEB, 0x8C, 0x1D, 0x6F, 0xFE, 0x8B, 0x1A,
72 0x68, 0xF9, 0x82, 0x13, 0x61, 0xF0, 0x85, 0x14, 0x66, 0xF7, 0xA8,
73 0x39, 0x4B, 0xDA, 0xAF, 0x3E, 0x4C, 0xDD, 0xA6, 0x37, 0x45, 0xD4,
74 0xA1, 0x30, 0x42, 0xD3, 0xB4, 0x25, 0x57, 0xC6, 0xB3, 0x22, 0x50,
75 0xC1, 0xBA, 0x2B, 0x59, 0xC8, 0xBD, 0x2C, 0x5E, 0xCF};
76
77 /*******************************************************************************
78 *
79 * Function rfc_calc_fcs
80 *
81 * Description This function calculate FCS for the RFCOMM frame
82 * (GSM 07.10 TS 101 369 V6.3.0)
83 *
84 * Input len - number of bytes in the message
85 * p - points to message
86 *
87 ******************************************************************************/
rfc_calc_fcs(uint16_t len,uint8_t * p)88 uint8_t rfc_calc_fcs(uint16_t len, uint8_t* p) {
89 uint8_t fcs = 0xFF;
90
91 while (len--) {
92 fcs = rfc_crctable[fcs ^ *p++];
93 }
94
95 /* Ones compliment */
96 return (0xFF - fcs);
97 }
98
99 /*******************************************************************************
100 *
101 * Function rfc_check_fcs
102 *
103 * Description This function checks FCS for the RFCOMM frame
104 * (GSM 07.10 TS 101 369 V6.3.0)
105 *
106 * Input len - number of bytes in the message
107 * p - points to message
108 * received_fcs - received FCS
109 *
110 ******************************************************************************/
rfc_check_fcs(uint16_t len,uint8_t * p,uint8_t received_fcs)111 bool rfc_check_fcs(uint16_t len, uint8_t* p, uint8_t received_fcs) {
112 uint8_t fcs = 0xFF;
113
114 while (len--) {
115 fcs = rfc_crctable[fcs ^ *p++];
116 }
117
118 /* Ones compliment */
119 fcs = rfc_crctable[fcs ^ received_fcs];
120
121 /*0xCF is the reversed order of 11110011.*/
122 return (fcs == 0xCF);
123 }
124
125 /*******************************************************************************
126 *
127 * Function rfc_alloc_multiplexer_channel
128 *
129 * Description This function returns existing or new control block for
130 * the address.
131 *
132 ******************************************************************************/
rfc_alloc_multiplexer_channel(const RawAddress & bd_addr,bool is_initiator)133 tRFC_MCB* rfc_alloc_multiplexer_channel(const RawAddress& bd_addr,
134 bool is_initiator) {
135 int i, j;
136 tRFC_MCB* p_mcb = NULL;
137 VLOG(1) << __func__ << ": bd_addr:" << bd_addr;
138 RFCOMM_TRACE_DEBUG("rfc_alloc_multiplexer_channel:is_initiator:%d",
139 is_initiator);
140
141 for (i = 0; i < MAX_BD_CONNECTIONS; i++) {
142 RFCOMM_TRACE_DEBUG(
143 "rfc_alloc_multiplexer_channel rfc_cb.port.rfc_mcb[%d].state:%d", i,
144 rfc_cb.port.rfc_mcb[i].state);
145 VLOG(1) << "(rfc_cb.port.rfc_mcb[i].bd_addr:"
146 << rfc_cb.port.rfc_mcb[i].bd_addr;
147
148 if ((rfc_cb.port.rfc_mcb[i].state != RFC_MX_STATE_IDLE) &&
149 rfc_cb.port.rfc_mcb[i].bd_addr == bd_addr) {
150 /* Multiplexer channel found do not change anything */
151 /* If there was an inactivity timer running stop it now */
152 if (rfc_cb.port.rfc_mcb[i].state == RFC_MX_STATE_CONNECTED)
153 rfc_timer_stop(&rfc_cb.port.rfc_mcb[i]);
154 RFCOMM_TRACE_DEBUG(
155 "rfc_alloc_multiplexer_channel:is_initiator:%d, found, state:%d, "
156 "p_mcb:%p",
157 is_initiator, rfc_cb.port.rfc_mcb[i].state, &rfc_cb.port.rfc_mcb[i]);
158 return (&rfc_cb.port.rfc_mcb[i]);
159 }
160 }
161
162 /* connection with bd_addr does not exist */
163 for (i = 0, j = rfc_cb.rfc.last_mux + 1; i < MAX_BD_CONNECTIONS; i++, j++) {
164 if (j >= MAX_BD_CONNECTIONS) j = 0;
165
166 p_mcb = &rfc_cb.port.rfc_mcb[j];
167 if (rfc_cb.port.rfc_mcb[j].state == RFC_MX_STATE_IDLE) {
168 /* New multiplexer control block */
169 alarm_free(p_mcb->mcb_timer);
170 fixed_queue_free(p_mcb->cmd_q, NULL);
171 memset(p_mcb, 0, sizeof(tRFC_MCB));
172 p_mcb->bd_addr = bd_addr;
173 RFCOMM_TRACE_DEBUG(
174 "rfc_alloc_multiplexer_channel:is_initiator:%d, create new p_mcb:%p, "
175 "index:%d",
176 is_initiator, &rfc_cb.port.rfc_mcb[j], j);
177
178 p_mcb->mcb_timer = alarm_new("rfcomm_mcb.mcb_timer");
179 p_mcb->cmd_q = fixed_queue_new(SIZE_MAX);
180
181 p_mcb->is_initiator = is_initiator;
182
183 rfc_timer_start(p_mcb, RFC_MCB_INIT_INACT_TIMER);
184
185 rfc_cb.rfc.last_mux = (uint8_t)j;
186 return (p_mcb);
187 }
188 }
189 return (NULL);
190 }
191
192 /*******************************************************************************
193 *
194 * Function rfc_release_multiplexer_channel
195 *
196 * Description Release a multiplexer control block
197 *
198 ******************************************************************************/
rfc_release_multiplexer_channel(tRFC_MCB * p_mcb)199 void rfc_release_multiplexer_channel(tRFC_MCB* p_mcb) {
200 /* Remove the MCB from the mapping table */
201 rfc_save_lcid_mcb(NULL, p_mcb->lcid);
202
203 /* Remove the MCB from the ports */
204 for (int i = 0; i < MAX_RFC_PORTS; i++) {
205 if (rfc_cb.port.port[i].rfc.p_mcb == p_mcb)
206 rfc_cb.port.port[i].rfc.p_mcb = NULL;
207 }
208
209 rfc_timer_stop(p_mcb);
210 alarm_free(p_mcb->mcb_timer);
211
212 fixed_queue_free(p_mcb->cmd_q, osi_free);
213
214 memset(p_mcb, 0, sizeof(tRFC_MCB));
215 p_mcb->state = RFC_MX_STATE_IDLE;
216 }
217
218 /*******************************************************************************
219 *
220 * Function rfc_timer_start
221 *
222 * Description Start RFC Timer
223 *
224 ******************************************************************************/
rfc_timer_start(tRFC_MCB * p_mcb,uint16_t timeout)225 void rfc_timer_start(tRFC_MCB* p_mcb, uint16_t timeout) {
226 RFCOMM_TRACE_EVENT("%s - timeout:%d seconds", __func__, timeout);
227
228 period_ms_t interval_ms = timeout * 1000;
229 alarm_set_on_mloop(p_mcb->mcb_timer, interval_ms, rfcomm_mcb_timer_timeout,
230 p_mcb);
231 }
232
233 /*******************************************************************************
234 *
235 * Function rfc_timer_stop
236 *
237 * Description Stop RFC Timer
238 *
239 ******************************************************************************/
rfc_timer_stop(tRFC_MCB * p_mcb)240 void rfc_timer_stop(tRFC_MCB* p_mcb) {
241 RFCOMM_TRACE_EVENT("%s", __func__);
242
243 alarm_cancel(p_mcb->mcb_timer);
244 }
245
246 /*******************************************************************************
247 *
248 * Function rfc_port_timer_start
249 *
250 * Description Start RFC Timer
251 *
252 ******************************************************************************/
rfc_port_timer_start(tPORT * p_port,uint16_t timeout)253 void rfc_port_timer_start(tPORT* p_port, uint16_t timeout) {
254 RFCOMM_TRACE_EVENT("%s - timeout:%d seconds", __func__, timeout);
255
256 period_ms_t interval_ms = timeout * 1000;
257 alarm_set_on_mloop(p_port->rfc.port_timer, interval_ms,
258 rfcomm_port_timer_timeout, p_port);
259 }
260
261 /*******************************************************************************
262 *
263 * Function rfc_port_timer_stop
264 *
265 * Description Stop RFC Timer
266 *
267 ******************************************************************************/
rfc_port_timer_stop(tPORT * p_port)268 void rfc_port_timer_stop(tPORT* p_port) {
269 RFCOMM_TRACE_EVENT("%s", __func__);
270
271 alarm_cancel(p_port->rfc.port_timer);
272 }
273
274 /*******************************************************************************
275 *
276 * Function rfc_check_mcb_active
277 *
278 * Description Check if there are any opened ports on the MCB if not
279 * start MCB Inact timer.
280 *
281 * Returns void
282 *
283 ******************************************************************************/
rfc_check_mcb_active(tRFC_MCB * p_mcb)284 void rfc_check_mcb_active(tRFC_MCB* p_mcb) {
285 uint16_t i;
286
287 for (i = 0; i < RFCOMM_MAX_DLCI; i++) {
288 if (p_mcb->port_inx[i] != 0) {
289 p_mcb->is_disc_initiator = false;
290 return;
291 }
292 }
293 /* The last port was DISCed. On the client side start disconnecting Mx */
294 /* On the server side start inactivity timer */
295 if (p_mcb->is_disc_initiator) {
296 p_mcb->is_disc_initiator = false;
297 rfc_mx_sm_execute(p_mcb, RFC_MX_EVENT_CLOSE_REQ, NULL);
298 } else
299 rfc_timer_start(p_mcb, RFC_MCB_RELEASE_INACT_TIMER);
300 }
301
rfcomm_port_timer_timeout(void * data)302 void rfcomm_port_timer_timeout(void* data) {
303 tPORT* p_port = (tPORT*)data;
304
305 rfc_port_sm_execute(p_port, RFC_EVENT_TIMEOUT, NULL);
306 }
307
rfcomm_mcb_timer_timeout(void * data)308 void rfcomm_mcb_timer_timeout(void* data) {
309 tRFC_MCB* p_mcb = (tRFC_MCB*)data;
310
311 rfc_mx_sm_execute(p_mcb, RFC_EVENT_TIMEOUT, NULL);
312 }
313
314 /*******************************************************************************
315 *
316 * Function rfc_sec_check_complete
317 *
318 * Description The function called when Security Manager finishes
319 * verification of the service side connection
320 *
321 * Returns void
322 *
323 ******************************************************************************/
rfc_sec_check_complete(UNUSED_ATTR const RawAddress * bd_addr,UNUSED_ATTR tBT_TRANSPORT transport,void * p_ref_data,uint8_t res)324 void rfc_sec_check_complete(UNUSED_ATTR const RawAddress* bd_addr,
325 UNUSED_ATTR tBT_TRANSPORT transport,
326 void* p_ref_data, uint8_t res) {
327 tPORT* p_port = (tPORT*)p_ref_data;
328
329 /* Verify that PORT is still waiting for Security to complete */
330 if (!p_port->in_use ||
331 ((p_port->rfc.state != RFC_STATE_ORIG_WAIT_SEC_CHECK) &&
332 (p_port->rfc.state != RFC_STATE_TERM_WAIT_SEC_CHECK)))
333 return;
334
335 rfc_port_sm_execute((tPORT*)p_ref_data, RFC_EVENT_SEC_COMPLETE, &res);
336 }
337
338 /*******************************************************************************
339 *
340 * Function rfc_port_closed
341 *
342 * Description The function is called when port is released based on the
343 * event received from the lower layer, typically L2CAP
344 * connection down, DISC, or DM frame.
345 *
346 * Returns void
347 *
348 ******************************************************************************/
rfc_port_closed(tPORT * p_port)349 void rfc_port_closed(tPORT* p_port) {
350 tRFC_MCB* p_mcb = p_port->rfc.p_mcb;
351 rfc_port_timer_stop(p_port);
352 p_port->rfc.state = RFC_STATE_CLOSED;
353
354 /* If multiplexer channel was up mark it as down */
355 if (p_mcb) {
356 p_mcb->port_inx[p_port->dlci] = 0;
357
358 /* If there are no more ports opened on this MCB release it */
359 rfc_check_mcb_active(p_mcb);
360 }
361
362 /* Notify port that RFC connection is gone */
363 port_rfc_closed(p_port, PORT_CLOSED);
364 }
365
366 /*******************************************************************************
367 *
368 * Function rfc_inc_credit
369 *
370 * Description The function is called when a credit is received in a UIH
371 * frame. It increments the TX credit count, and if data
372 * flow had halted, it restarts it.
373 *
374 * Returns void
375 *
376 ******************************************************************************/
rfc_inc_credit(tPORT * p_port,uint8_t credit)377 void rfc_inc_credit(tPORT* p_port, uint8_t credit) {
378 if (p_port->rfc.p_mcb->flow == PORT_FC_CREDIT) {
379 p_port->credit_tx += credit;
380
381 RFCOMM_TRACE_EVENT("rfc_inc_credit:%d", p_port->credit_tx);
382
383 if (p_port->tx.peer_fc == true)
384 PORT_FlowInd(p_port->rfc.p_mcb, p_port->dlci, true);
385 }
386 }
387
388 /*******************************************************************************
389 *
390 * Function rfc_dec_credit
391 *
392 * Description The function is called when a UIH frame of user data is
393 * sent. It decrements the credit count. If credit count
394 * Reaches zero, peer_fc is set.
395 *
396 * Returns void
397 *
398 ******************************************************************************/
rfc_dec_credit(tPORT * p_port)399 void rfc_dec_credit(tPORT* p_port) {
400 if (p_port->rfc.p_mcb->flow == PORT_FC_CREDIT) {
401 if (p_port->credit_tx > 0) p_port->credit_tx--;
402
403 if (p_port->credit_tx == 0) p_port->tx.peer_fc = true;
404 }
405 }
406
407 /*******************************************************************************
408 *
409 * Function rfc_check_send_cmd
410 *
411 * Description This function is called to send an RFCOMM command message
412 * or to handle the RFCOMM command message queue.
413 *
414 * Returns void
415 *
416 ******************************************************************************/
rfc_check_send_cmd(tRFC_MCB * p_mcb,BT_HDR * p_buf)417 void rfc_check_send_cmd(tRFC_MCB* p_mcb, BT_HDR* p_buf) {
418 /* if passed a buffer queue it */
419 if (p_buf != NULL) {
420 if (p_mcb->cmd_q == NULL) {
421 RFCOMM_TRACE_ERROR(
422 "%s: empty queue: p_mcb = %p p_mcb->lcid = %u cached p_mcb = %p",
423 __func__, p_mcb, p_mcb->lcid, rfc_find_lcid_mcb(p_mcb->lcid));
424 }
425 fixed_queue_enqueue(p_mcb->cmd_q, p_buf);
426 }
427
428 /* handle queue if L2CAP not congested */
429 while (p_mcb->l2cap_congested == false) {
430 BT_HDR* p = (BT_HDR*)fixed_queue_try_dequeue(p_mcb->cmd_q);
431 if (p == NULL) break;
432 L2CA_DataWrite(p_mcb->lcid, p);
433 }
434 }
435