1 /******************************************************************************
2 *
3 * Copyright 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 "btu.h"
31 #include "osi/include/osi.h"
32 #include "port_api.h"
33 #include "port_ext.h"
34 #include "port_int.h"
35 #include "rfc_int.h"
36 #include "rfcdefs.h"
37
38 #include <string.h>
39
40 /*******************************************************************************
41 *
42 * Function rfc_calc_fcs
43 *
44 * Description Reversed CRC Table , 8-bit, poly=0x07
45 * (GSM 07.10 TS 101 369 V6.3.0)
46 ******************************************************************************/
47 static const uint8_t rfc_crctable[] = {
48 0x00, 0x91, 0xE3, 0x72, 0x07, 0x96, 0xE4, 0x75, 0x0E, 0x9F, 0xED,
49 0x7C, 0x09, 0x98, 0xEA, 0x7B, 0x1C, 0x8D, 0xFF, 0x6E, 0x1B, 0x8A,
50 0xF8, 0x69, 0x12, 0x83, 0xF1, 0x60, 0x15, 0x84, 0xF6, 0x67, 0x38,
51 0xA9, 0xDB, 0x4A, 0x3F, 0xAE, 0xDC, 0x4D, 0x36, 0xA7, 0xD5, 0x44,
52 0x31, 0xA0, 0xD2, 0x43, 0x24, 0xB5, 0xC7, 0x56, 0x23, 0xB2, 0xC0,
53 0x51, 0x2A, 0xBB, 0xC9, 0x58, 0x2D, 0xBC, 0xCE, 0x5F,
54
55 0x70, 0xE1, 0x93, 0x02, 0x77, 0xE6, 0x94, 0x05, 0x7E, 0xEF, 0x9D,
56 0x0C, 0x79, 0xE8, 0x9A, 0x0B, 0x6C, 0xFD, 0x8F, 0x1E, 0x6B, 0xFA,
57 0x88, 0x19, 0x62, 0xF3, 0x81, 0x10, 0x65, 0xF4, 0x86, 0x17, 0x48,
58 0xD9, 0xAB, 0x3A, 0x4F, 0xDE, 0xAC, 0x3D, 0x46, 0xD7, 0xA5, 0x34,
59 0x41, 0xD0, 0xA2, 0x33, 0x54, 0xC5, 0xB7, 0x26, 0x53, 0xC2, 0xB0,
60 0x21, 0x5A, 0xCB, 0xB9, 0x28, 0x5D, 0xCC, 0xBE, 0x2F,
61
62 0xE0, 0x71, 0x03, 0x92, 0xE7, 0x76, 0x04, 0x95, 0xEE, 0x7F, 0x0D,
63 0x9C, 0xE9, 0x78, 0x0A, 0x9B, 0xFC, 0x6D, 0x1F, 0x8E, 0xFB, 0x6A,
64 0x18, 0x89, 0xF2, 0x63, 0x11, 0x80, 0xF5, 0x64, 0x16, 0x87, 0xD8,
65 0x49, 0x3B, 0xAA, 0xDF, 0x4E, 0x3C, 0xAD, 0xD6, 0x47, 0x35, 0xA4,
66 0xD1, 0x40, 0x32, 0xA3, 0xC4, 0x55, 0x27, 0xB6, 0xC3, 0x52, 0x20,
67 0xB1, 0xCA, 0x5B, 0x29, 0xB8, 0xCD, 0x5C, 0x2E, 0xBF,
68
69 0x90, 0x01, 0x73, 0xE2, 0x97, 0x06, 0x74, 0xE5, 0x9E, 0x0F, 0x7D,
70 0xEC, 0x99, 0x08, 0x7A, 0xEB, 0x8C, 0x1D, 0x6F, 0xFE, 0x8B, 0x1A,
71 0x68, 0xF9, 0x82, 0x13, 0x61, 0xF0, 0x85, 0x14, 0x66, 0xF7, 0xA8,
72 0x39, 0x4B, 0xDA, 0xAF, 0x3E, 0x4C, 0xDD, 0xA6, 0x37, 0x45, 0xD4,
73 0xA1, 0x30, 0x42, 0xD3, 0xB4, 0x25, 0x57, 0xC6, 0xB3, 0x22, 0x50,
74 0xC1, 0xBA, 0x2B, 0x59, 0xC8, 0xBD, 0x2C, 0x5E, 0xCF};
75
76 /*******************************************************************************
77 *
78 * Function rfc_calc_fcs
79 *
80 * Description This function calculate FCS for the RFCOMM frame
81 * (GSM 07.10 TS 101 369 V6.3.0)
82 *
83 * Input len - number of bytes in the message
84 * p - points to message
85 *
86 ******************************************************************************/
rfc_calc_fcs(uint16_t len,uint8_t * p)87 uint8_t rfc_calc_fcs(uint16_t len, uint8_t* p) {
88 uint8_t fcs = 0xFF;
89
90 while (len--) {
91 fcs = rfc_crctable[fcs ^ *p++];
92 }
93
94 /* Ones compliment */
95 return (0xFF - fcs);
96 }
97
98 /*******************************************************************************
99 *
100 * Function rfc_check_fcs
101 *
102 * Description This function checks FCS for the RFCOMM frame
103 * (GSM 07.10 TS 101 369 V6.3.0)
104 *
105 * Input len - number of bytes in the message
106 * p - points to message
107 * received_fcs - received FCS
108 *
109 ******************************************************************************/
rfc_check_fcs(uint16_t len,uint8_t * p,uint8_t received_fcs)110 bool rfc_check_fcs(uint16_t len, uint8_t* p, uint8_t received_fcs) {
111 uint8_t fcs = 0xFF;
112
113 while (len--) {
114 fcs = rfc_crctable[fcs ^ *p++];
115 }
116
117 /* Ones compliment */
118 fcs = rfc_crctable[fcs ^ received_fcs];
119
120 /*0xCF is the reversed order of 11110011.*/
121 return (fcs == 0xCF);
122 }
123
124 /*******************************************************************************
125 *
126 * Function rfc_alloc_multiplexer_channel
127 *
128 * Description This function returns existing or new control block for
129 * the address.
130 *
131 ******************************************************************************/
rfc_alloc_multiplexer_channel(const RawAddress & bd_addr,bool is_initiator)132 tRFC_MCB* rfc_alloc_multiplexer_channel(const RawAddress& bd_addr,
133 bool is_initiator) {
134 int i, j;
135 tRFC_MCB* p_mcb = NULL;
136 VLOG(1) << __func__ << ": bd_addr:" << bd_addr;
137 RFCOMM_TRACE_DEBUG("rfc_alloc_multiplexer_channel:is_initiator:%d",
138 is_initiator);
139
140 for (i = 0; i < MAX_BD_CONNECTIONS; i++) {
141 RFCOMM_TRACE_DEBUG(
142 "rfc_alloc_multiplexer_channel rfc_cb.port.rfc_mcb[%d].state:%d", i,
143 rfc_cb.port.rfc_mcb[i].state);
144 VLOG(1) << "(rfc_cb.port.rfc_mcb[i].bd_addr:"
145 << rfc_cb.port.rfc_mcb[i].bd_addr;
146
147 if ((rfc_cb.port.rfc_mcb[i].state != RFC_MX_STATE_IDLE) &&
148 rfc_cb.port.rfc_mcb[i].bd_addr == bd_addr) {
149 /* Multiplexer channel found do not change anything */
150 /* If there was an inactivity timer running stop it now */
151 if (rfc_cb.port.rfc_mcb[i].state == RFC_MX_STATE_CONNECTED)
152 rfc_timer_stop(&rfc_cb.port.rfc_mcb[i]);
153 RFCOMM_TRACE_DEBUG(
154 "rfc_alloc_multiplexer_channel:is_initiator:%d, found, state:%d, "
155 "p_mcb:%p",
156 is_initiator, rfc_cb.port.rfc_mcb[i].state, &rfc_cb.port.rfc_mcb[i]);
157 return (&rfc_cb.port.rfc_mcb[i]);
158 }
159 }
160
161 /* connection with bd_addr does not exist */
162 for (i = 0, j = rfc_cb.rfc.last_mux + 1; i < MAX_BD_CONNECTIONS; i++, j++) {
163 if (j >= MAX_BD_CONNECTIONS) j = 0;
164
165 p_mcb = &rfc_cb.port.rfc_mcb[j];
166 if (rfc_cb.port.rfc_mcb[j].state == RFC_MX_STATE_IDLE) {
167 /* New multiplexer control block */
168 alarm_free(p_mcb->mcb_timer);
169 fixed_queue_free(p_mcb->cmd_q, NULL);
170 memset(p_mcb, 0, sizeof(tRFC_MCB));
171 p_mcb->bd_addr = bd_addr;
172 RFCOMM_TRACE_DEBUG(
173 "rfc_alloc_multiplexer_channel:is_initiator:%d, create new p_mcb:%p, "
174 "index:%d",
175 is_initiator, &rfc_cb.port.rfc_mcb[j], j);
176
177 p_mcb->mcb_timer = alarm_new("rfcomm_mcb.mcb_timer");
178 p_mcb->cmd_q = fixed_queue_new(SIZE_MAX);
179
180 p_mcb->is_initiator = is_initiator;
181
182 rfc_timer_start(p_mcb, RFC_MCB_INIT_INACT_TIMER);
183
184 rfc_cb.rfc.last_mux = (uint8_t)j;
185 return (p_mcb);
186 }
187 }
188 return (NULL);
189 }
190
191 /*******************************************************************************
192 *
193 * Function rfc_release_multiplexer_channel
194 *
195 * Description Release a multiplexer control block
196 *
197 ******************************************************************************/
rfc_release_multiplexer_channel(tRFC_MCB * p_mcb)198 void rfc_release_multiplexer_channel(tRFC_MCB* p_mcb) {
199 /* Remove the MCB from the mapping table */
200 rfc_save_lcid_mcb(NULL, p_mcb->lcid);
201
202 /* Remove the MCB from the ports */
203 for (int i = 0; i < MAX_RFC_PORTS; i++) {
204 if (rfc_cb.port.port[i].rfc.p_mcb == p_mcb)
205 rfc_cb.port.port[i].rfc.p_mcb = NULL;
206 }
207
208 rfc_timer_stop(p_mcb);
209 alarm_free(p_mcb->mcb_timer);
210
211 fixed_queue_free(p_mcb->cmd_q, osi_free);
212
213 memset(p_mcb, 0, sizeof(tRFC_MCB));
214 p_mcb->state = RFC_MX_STATE_IDLE;
215 }
216
217 /*******************************************************************************
218 *
219 * Function rfc_timer_start
220 *
221 * Description Start RFC Timer
222 *
223 ******************************************************************************/
rfc_timer_start(tRFC_MCB * p_mcb,uint16_t timeout)224 void rfc_timer_start(tRFC_MCB* p_mcb, uint16_t timeout) {
225 RFCOMM_TRACE_EVENT("%s - timeout:%d seconds", __func__, timeout);
226
227 uint64_t interval_ms = timeout * 1000;
228 alarm_set_on_mloop(p_mcb->mcb_timer, interval_ms, rfcomm_mcb_timer_timeout,
229 p_mcb);
230 }
231
232 /*******************************************************************************
233 *
234 * Function rfc_timer_stop
235 *
236 * Description Stop RFC Timer
237 *
238 ******************************************************************************/
rfc_timer_stop(tRFC_MCB * p_mcb)239 void rfc_timer_stop(tRFC_MCB* p_mcb) {
240 RFCOMM_TRACE_EVENT("%s", __func__);
241
242 alarm_cancel(p_mcb->mcb_timer);
243 }
244
245 /*******************************************************************************
246 *
247 * Function rfc_port_timer_start
248 *
249 * Description Start RFC Timer
250 *
251 ******************************************************************************/
rfc_port_timer_start(tPORT * p_port,uint16_t timeout)252 void rfc_port_timer_start(tPORT* p_port, uint16_t timeout) {
253 RFCOMM_TRACE_EVENT("%s - timeout:%d seconds", __func__, timeout);
254
255 uint64_t interval_ms = timeout * 1000;
256 alarm_set_on_mloop(p_port->rfc.port_timer, interval_ms,
257 rfcomm_port_timer_timeout, p_port);
258 }
259
260 /*******************************************************************************
261 *
262 * Function rfc_port_timer_stop
263 *
264 * Description Stop RFC Timer
265 *
266 ******************************************************************************/
rfc_port_timer_stop(tPORT * p_port)267 void rfc_port_timer_stop(tPORT* p_port) {
268 RFCOMM_TRACE_EVENT("%s", __func__);
269
270 alarm_cancel(p_port->rfc.port_timer);
271 }
272
273 /*******************************************************************************
274 *
275 * Function rfc_check_mcb_active
276 *
277 * Description Check if there are any opened ports on the MCB if not
278 * start MCB Inact timer.
279 *
280 * Returns void
281 *
282 ******************************************************************************/
rfc_check_mcb_active(tRFC_MCB * p_mcb)283 void rfc_check_mcb_active(tRFC_MCB* p_mcb) {
284 uint16_t i;
285
286 for (i = 0; i < RFCOMM_MAX_DLCI; i++) {
287 if (p_mcb->port_handles[i] != 0) {
288 p_mcb->is_disc_initiator = false;
289 return;
290 }
291 }
292 /* The last port was DISCed. On the client side start disconnecting Mx */
293 /* On the server side start inactivity timer */
294 if (p_mcb->is_disc_initiator) {
295 p_mcb->is_disc_initiator = false;
296 rfc_mx_sm_execute(p_mcb, RFC_MX_EVENT_CLOSE_REQ, NULL);
297 } else
298 rfc_timer_start(p_mcb, RFC_MCB_RELEASE_INACT_TIMER);
299 }
300
rfcomm_port_timer_timeout(void * data)301 void rfcomm_port_timer_timeout(void* data) {
302 tPORT* p_port = (tPORT*)data;
303
304 rfc_port_sm_execute(p_port, RFC_EVENT_TIMEOUT, NULL);
305 }
306
rfcomm_mcb_timer_timeout(void * data)307 void rfcomm_mcb_timer_timeout(void* data) {
308 tRFC_MCB* p_mcb = (tRFC_MCB*)data;
309
310 rfc_mx_sm_execute(p_mcb, RFC_EVENT_TIMEOUT, NULL);
311 }
312
313 /*******************************************************************************
314 *
315 * Function rfc_sec_check_complete
316 *
317 * Description The function called when Security Manager finishes
318 * verification of the service side connection
319 *
320 * Returns void
321 *
322 ******************************************************************************/
rfc_sec_check_complete(UNUSED_ATTR const RawAddress * bd_addr,UNUSED_ATTR tBT_TRANSPORT transport,void * p_ref_data,tBTM_STATUS res)323 void rfc_sec_check_complete(UNUSED_ATTR const RawAddress* bd_addr,
324 UNUSED_ATTR tBT_TRANSPORT transport,
325 void* p_ref_data, tBTM_STATUS res) {
326 tPORT* p_port = (tPORT*)p_ref_data;
327
328 /* Verify that PORT is still waiting for Security to complete */
329 if (!p_port->in_use ||
330 ((p_port->rfc.state != RFC_STATE_ORIG_WAIT_SEC_CHECK) &&
331 (p_port->rfc.state != RFC_STATE_TERM_WAIT_SEC_CHECK)))
332 return;
333
334 rfc_port_sm_execute((tPORT*)p_ref_data, RFC_EVENT_SEC_COMPLETE, &res);
335 }
336
337 /*******************************************************************************
338 *
339 * Function rfc_port_closed
340 *
341 * Description The function is called when port is released based on the
342 * event received from the lower layer, typically L2CAP
343 * connection down, DISC, or DM frame.
344 *
345 * Returns void
346 *
347 ******************************************************************************/
rfc_port_closed(tPORT * p_port)348 void rfc_port_closed(tPORT* p_port) {
349 tRFC_MCB* p_mcb = p_port->rfc.p_mcb;
350 rfc_port_timer_stop(p_port);
351 p_port->rfc.state = RFC_STATE_CLOSED;
352
353 /* If multiplexer channel was up mark it as down */
354 if (p_mcb) {
355 p_mcb->port_handles[p_port->dlci] = 0;
356
357 /* If there are no more ports opened on this MCB release it */
358 rfc_check_mcb_active(p_mcb);
359 }
360
361 /* Notify port that RFC connection is gone */
362 port_rfc_closed(p_port, PORT_CLOSED);
363 }
364
365 /*******************************************************************************
366 *
367 * Function rfc_inc_credit
368 *
369 * Description The function is called when a credit is received in a UIH
370 * frame. It increments the TX credit count, and if data
371 * flow had halted, it restarts it.
372 *
373 * Returns void
374 *
375 ******************************************************************************/
rfc_inc_credit(tPORT * p_port,uint8_t credit)376 void rfc_inc_credit(tPORT* p_port, uint8_t credit) {
377 if (p_port->rfc.p_mcb->flow == PORT_FC_CREDIT) {
378 p_port->credit_tx += credit;
379
380 RFCOMM_TRACE_EVENT("rfc_inc_credit:%d", p_port->credit_tx);
381
382 if (p_port->tx.peer_fc) PORT_FlowInd(p_port->rfc.p_mcb, p_port->dlci, true);
383 }
384 }
385
386 /*******************************************************************************
387 *
388 * Function rfc_dec_credit
389 *
390 * Description The function is called when a UIH frame of user data is
391 * sent. It decrements the credit count. If credit count
392 * Reaches zero, peer_fc is set.
393 *
394 * Returns void
395 *
396 ******************************************************************************/
rfc_dec_credit(tPORT * p_port)397 void rfc_dec_credit(tPORT* p_port) {
398 if (p_port->rfc.p_mcb->flow == PORT_FC_CREDIT) {
399 if (p_port->credit_tx > 0) p_port->credit_tx--;
400
401 if (p_port->credit_tx == 0) p_port->tx.peer_fc = true;
402 }
403 }
404
405 /*******************************************************************************
406 *
407 * Function rfc_check_send_cmd
408 *
409 * Description This function is called to send an RFCOMM command message
410 * or to handle the RFCOMM command message queue.
411 *
412 * Returns void
413 *
414 ******************************************************************************/
rfc_check_send_cmd(tRFC_MCB * p_mcb,BT_HDR * p_buf)415 void rfc_check_send_cmd(tRFC_MCB* p_mcb, BT_HDR* p_buf) {
416 /* if passed a buffer queue it */
417 if (p_buf != NULL) {
418 if (p_mcb->cmd_q == NULL) {
419 RFCOMM_TRACE_ERROR(
420 "%s: empty queue: p_mcb = %p p_mcb->lcid = %u cached p_mcb = %p",
421 __func__, p_mcb, p_mcb->lcid, rfc_find_lcid_mcb(p_mcb->lcid));
422 }
423 fixed_queue_enqueue(p_mcb->cmd_q, p_buf);
424 }
425
426 /* handle queue if L2CAP not congested */
427 while (!p_mcb->l2cap_congested) {
428 BT_HDR* p = (BT_HDR*)fixed_queue_try_dequeue(p_mcb->cmd_q);
429 if (p == NULL) break;
430 L2CA_DataWrite(p_mcb->lcid, p);
431 }
432 }
433