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_target.h"
26 #include "gki.h"
27 
28 #include "btm_api.h"
29 #include "btm_int.h"
30 #include "rfcdefs.h"
31 #include "port_api.h"
32 #include "port_ext.h"
33 #include "port_int.h"
34 #include "rfc_int.h"
35 #include "btu.h"
36 #include "bt_utils.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 rfc_crctable[] =
48 {
49     0x00, 0x91, 0xE3, 0x72, 0x07, 0x96, 0xE4, 0x75,  0x0E, 0x9F, 0xED, 0x7C, 0x09, 0x98, 0xEA, 0x7B,
50     0x1C, 0x8D, 0xFF, 0x6E, 0x1B, 0x8A, 0xF8, 0x69,  0x12, 0x83, 0xF1, 0x60, 0x15, 0x84, 0xF6, 0x67,
51     0x38, 0xA9, 0xDB, 0x4A, 0x3F, 0xAE, 0xDC, 0x4D,  0x36, 0xA7, 0xD5, 0x44, 0x31, 0xA0, 0xD2, 0x43,
52     0x24, 0xB5, 0xC7, 0x56, 0x23, 0xB2, 0xC0, 0x51,  0x2A, 0xBB, 0xC9, 0x58, 0x2D, 0xBC, 0xCE, 0x5F,
53 
54     0x70, 0xE1, 0x93, 0x02, 0x77, 0xE6, 0x94, 0x05,  0x7E, 0xEF, 0x9D, 0x0C, 0x79, 0xE8, 0x9A, 0x0B,
55     0x6C, 0xFD, 0x8F, 0x1E, 0x6B, 0xFA, 0x88, 0x19,  0x62, 0xF3, 0x81, 0x10, 0x65, 0xF4, 0x86, 0x17,
56     0x48, 0xD9, 0xAB, 0x3A, 0x4F, 0xDE, 0xAC, 0x3D,  0x46, 0xD7, 0xA5, 0x34, 0x41, 0xD0, 0xA2, 0x33,
57     0x54, 0xC5, 0xB7, 0x26, 0x53, 0xC2, 0xB0, 0x21,  0x5A, 0xCB, 0xB9, 0x28, 0x5D, 0xCC, 0xBE, 0x2F,
58 
59     0xE0, 0x71, 0x03, 0x92, 0xE7, 0x76, 0x04, 0x95,  0xEE, 0x7F, 0x0D, 0x9C, 0xE9, 0x78, 0x0A, 0x9B,
60     0xFC, 0x6D, 0x1F, 0x8E, 0xFB, 0x6A, 0x18, 0x89,  0xF2, 0x63, 0x11, 0x80, 0xF5, 0x64, 0x16, 0x87,
61     0xD8, 0x49, 0x3B, 0xAA, 0xDF, 0x4E, 0x3C, 0xAD,  0xD6, 0x47, 0x35, 0xA4, 0xD1, 0x40, 0x32, 0xA3,
62     0xC4, 0x55, 0x27, 0xB6, 0xC3, 0x52, 0x20, 0xB1,  0xCA, 0x5B, 0x29, 0xB8, 0xCD, 0x5C, 0x2E, 0xBF,
63 
64     0x90, 0x01, 0x73, 0xE2, 0x97, 0x06, 0x74, 0xE5,  0x9E, 0x0F, 0x7D, 0xEC, 0x99, 0x08, 0x7A, 0xEB,
65     0x8C, 0x1D, 0x6F, 0xFE, 0x8B, 0x1A, 0x68, 0xF9,  0x82, 0x13, 0x61, 0xF0, 0x85, 0x14, 0x66, 0xF7,
66     0xA8, 0x39, 0x4B, 0xDA, 0xAF, 0x3E, 0x4C, 0xDD,  0xA6, 0x37, 0x45, 0xD4, 0xA1, 0x30, 0x42, 0xD3,
67     0xB4, 0x25, 0x57, 0xC6, 0xB3, 0x22, 0x50, 0xC1,  0xBA, 0x2B, 0x59, 0xC8, 0xBD, 0x2C, 0x5E, 0xCF
68 };
69 
70 
71 /*******************************************************************************
72 **
73 ** Function         rfc_calc_fcs
74 **
75 ** Description      This function calculate FCS for the RFCOMM frame
76 **                  (GSM 07.10 TS 101 369 V6.3.0)
77 **
78 ** Input            len - number of bytes in the message
79 **                  p   - points to message
80 **
81 *******************************************************************************/
rfc_calc_fcs(UINT16 len,UINT8 * p)82 UINT8 rfc_calc_fcs (UINT16 len, UINT8 *p)
83 {
84     UINT8  fcs = 0xFF;
85 
86     while (len--)
87     {
88         fcs = rfc_crctable[fcs ^ *p++];
89     }
90 
91     /* Ones compliment */
92     return (0xFF - fcs);
93 }
94 
95 
96 /*******************************************************************************
97 **
98 ** Function         rfc_check_fcs
99 **
100 ** Description      This function checks FCS for the RFCOMM frame
101 **                  (GSM 07.10 TS 101 369 V6.3.0)
102 **
103 ** Input            len          - number of bytes in the message
104 **                  p            - points to message
105 **                  received_fcs - received FCS
106 **
107 *******************************************************************************/
rfc_check_fcs(UINT16 len,UINT8 * p,UINT8 received_fcs)108 BOOLEAN rfc_check_fcs (UINT16 len, UINT8 *p, UINT8 received_fcs)
109 {
110     UINT8  fcs = 0xFF;
111 
112     while (len--)
113     {
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 **
127 ** Function         rfc_alloc_multiplexer_channel
128 **
129 ** Description      This function returns existing or new control block for
130 **                  the BD_ADDR.
131 **
132 *******************************************************************************/
rfc_alloc_multiplexer_channel(BD_ADDR bd_addr,BOOLEAN is_initiator)133 tRFC_MCB *rfc_alloc_multiplexer_channel (BD_ADDR bd_addr, BOOLEAN is_initiator)
134 {
135     int i, j;
136     tRFC_MCB *p_mcb = NULL;
137     RFCOMM_TRACE_DEBUG("rfc_alloc_multiplexer_channel: bd_addr:%02x:%02x:%02x:%02x:%02x:%02x",
138                                 bd_addr[0], bd_addr[1], bd_addr[2], bd_addr[3], bd_addr[4], bd_addr[5]);
139     RFCOMM_TRACE_DEBUG("rfc_alloc_multiplexer_channel:is_initiator:%d", is_initiator);
140 
141     for (i = 0; i < MAX_BD_CONNECTIONS; i++)
142     {
143         RFCOMM_TRACE_DEBUG("rfc_alloc_multiplexer_channel rfc_cb.port.rfc_mcb[%d].state:%d",
144                             i, rfc_cb.port.rfc_mcb[i].state);
145         RFCOMM_TRACE_DEBUG("(rfc_cb.port.rfc_mcb[i].bd_addr:%02x:%02x:%02x:%02x:%02x:%02x",
146                                 rfc_cb.port.rfc_mcb[i].bd_addr[0], rfc_cb.port.rfc_mcb[i].bd_addr[1],
147                                 rfc_cb.port.rfc_mcb[i].bd_addr[2], rfc_cb.port.rfc_mcb[i].bd_addr[3],
148                                 rfc_cb.port.rfc_mcb[i].bd_addr[4], rfc_cb.port.rfc_mcb[i].bd_addr[5]);
149 
150         if ((rfc_cb.port.rfc_mcb[i].state != RFC_MX_STATE_IDLE)
151          && (!memcmp (rfc_cb.port.rfc_mcb[i].bd_addr, bd_addr, BD_ADDR_LEN)))
152         {
153             /* Multiplexer channel found do not change anything */
154             /* If there was an inactivity timer running stop it now */
155             if (rfc_cb.port.rfc_mcb[i].state == RFC_MX_STATE_CONNECTED)
156                 rfc_timer_stop (&rfc_cb.port.rfc_mcb[i]);
157             RFCOMM_TRACE_DEBUG("rfc_alloc_multiplexer_channel:is_initiator:%d, found, state:%d, p_mcb:%p",
158                                 is_initiator, rfc_cb.port.rfc_mcb[i].state, &rfc_cb.port.rfc_mcb[i]);
159             return (&rfc_cb.port.rfc_mcb[i]);
160         }
161     }
162 
163     /* connection with bd_addr does not exist */
164     for (i = 0, j = rfc_cb.rfc.last_mux + 1; i < MAX_BD_CONNECTIONS; i++, j++)
165     {
166         if (j >= MAX_BD_CONNECTIONS)
167             j = 0;
168 
169         p_mcb = &rfc_cb.port.rfc_mcb[j];
170         if (rfc_cb.port.rfc_mcb[j].state == RFC_MX_STATE_IDLE)
171         {
172             /* New multiplexer control block */
173             memset (p_mcb, 0, sizeof (tRFC_MCB));
174             memcpy (p_mcb->bd_addr, bd_addr, BD_ADDR_LEN);
175             RFCOMM_TRACE_DEBUG("rfc_alloc_multiplexer_channel:is_initiator:%d, create new p_mcb:%p, index:%d",
176                                 is_initiator, &rfc_cb.port.rfc_mcb[j], j);
177 
178             GKI_init_q(&p_mcb->cmd_q);
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) j;
185             return (p_mcb);
186         }
187     }
188     return (NULL);
189 }
190 
191 
192 /*******************************************************************************
193 **
194 ** Function         rfc_release_multiplexer_channel
195 **
196 ** Description      This function returns existing or new control block for
197 **                  the BD_ADDR.
198 **
199 *******************************************************************************/
rfc_release_multiplexer_channel(tRFC_MCB * p_mcb)200 void rfc_release_multiplexer_channel (tRFC_MCB *p_mcb)
201 {
202     void    *p_buf;
203 
204     rfc_timer_stop (p_mcb);
205 
206     while ((p_buf = GKI_dequeue(&p_mcb->cmd_q)) != NULL)
207         GKI_freebuf(p_buf);
208 
209     memset (p_mcb, 0, sizeof (tRFC_MCB));
210     p_mcb->state = RFC_MX_STATE_IDLE;
211 }
212 
213 
214 /*******************************************************************************
215 **
216 ** Function         rfc_timer_start
217 **
218 ** Description      Start RFC Timer
219 **
220 *******************************************************************************/
rfc_timer_start(tRFC_MCB * p_mcb,UINT16 timeout)221 void rfc_timer_start (tRFC_MCB *p_mcb, UINT16 timeout)
222 {
223     TIMER_LIST_ENT *p_tle = &p_mcb->tle;
224 
225     RFCOMM_TRACE_EVENT ("rfc_timer_start - timeout:%d", timeout);
226 
227     p_tle->param = (UINT32)p_mcb;
228 
229     btu_start_timer (p_tle, BTU_TTYPE_RFCOMM_MFC, timeout);
230 }
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 {
242     RFCOMM_TRACE_EVENT ("rfc_timer_stop");
243 
244     btu_stop_timer (&p_mcb->tle);
245 }
246 
247 
248 /*******************************************************************************
249 **
250 ** Function         rfc_port_timer_start
251 **
252 ** Description      Start RFC Timer
253 **
254 *******************************************************************************/
rfc_port_timer_start(tPORT * p_port,UINT16 timeout)255 void rfc_port_timer_start (tPORT *p_port, UINT16 timeout)
256 {
257     TIMER_LIST_ENT *p_tle = &p_port->rfc.tle;
258 
259     RFCOMM_TRACE_EVENT ("rfc_port_timer_start - timeout:%d", timeout);
260 
261     p_tle->param = (UINT32)p_port;
262 
263     btu_start_timer (p_tle, BTU_TTYPE_RFCOMM_PORT, timeout);
264 }
265 
266 
267 /*******************************************************************************
268 **
269 ** Function         rfc_port_timer_stop
270 **
271 ** Description      Stop RFC Timer
272 **
273 *******************************************************************************/
rfc_port_timer_stop(tPORT * p_port)274 void rfc_port_timer_stop (tPORT *p_port)
275 {
276     RFCOMM_TRACE_EVENT ("rfc_port_timer_stop");
277 
278     btu_stop_timer (&p_port->rfc.tle);
279 }
280 
281 
282 /*******************************************************************************
283 **
284 ** Function         rfc_check_mcb_active
285 **
286 ** Description      Check if there are any opened ports on the MCB if not
287 **                  start MCB Inact timer.
288 **
289 ** Returns          void
290 **
291 *******************************************************************************/
rfc_check_mcb_active(tRFC_MCB * p_mcb)292 void rfc_check_mcb_active (tRFC_MCB *p_mcb)
293 {
294     UINT16 i;
295 
296     for (i = 0; i < RFCOMM_MAX_DLCI; i++)
297     {
298         if (p_mcb->port_inx[i] != 0)
299         {
300             p_mcb->is_disc_initiator = FALSE;
301             return;
302         }
303     }
304     /* The last port was DISCed.  On the client side start disconnecting Mx */
305     /* On the server side start inactivity timer */
306     if (p_mcb->is_disc_initiator)
307     {
308         p_mcb->is_disc_initiator = FALSE;
309         rfc_mx_sm_execute (p_mcb, RFC_MX_EVENT_CLOSE_REQ, NULL);
310     }
311     else
312         rfc_timer_start (p_mcb, RFC_MCB_RELEASE_INACT_TIMER);
313 }
314 
315 
316 /*******************************************************************************
317 **
318 ** Function         rfcomm_process_timeout
319 **
320 ** Description      The function called every second to check RFCOMM timers
321 **
322 ** Returns          void
323 **
324 *******************************************************************************/
rfcomm_process_timeout(TIMER_LIST_ENT * p_tle)325 void rfcomm_process_timeout (TIMER_LIST_ENT  *p_tle)
326 {
327     switch (p_tle->event)
328     {
329     case BTU_TTYPE_RFCOMM_MFC:
330         rfc_mx_sm_execute ((tRFC_MCB *)p_tle->param, RFC_EVENT_TIMEOUT, NULL);
331         break;
332 
333     case BTU_TTYPE_RFCOMM_PORT:
334         rfc_port_sm_execute ((tPORT *)p_tle->param, RFC_EVENT_TIMEOUT, NULL);
335         break;
336 
337     default:
338         break;
339     }
340 }
341 
342 
343 /*******************************************************************************
344 **
345 ** Function         rfc_sec_check_complete
346 **
347 ** Description      The function called when Security Manager finishes
348 **                  verification of the service side connection
349 **
350 ** Returns          void
351 **
352 *******************************************************************************/
rfc_sec_check_complete(BD_ADDR bd_addr,tBT_TRANSPORT transport,void * p_ref_data,UINT8 res)353 void rfc_sec_check_complete (BD_ADDR bd_addr, tBT_TRANSPORT transport, void *p_ref_data, UINT8 res)
354 {
355     tPORT *p_port = (tPORT *)p_ref_data;
356     UNUSED(bd_addr);
357     UNUSED(transport);
358 
359     /* Verify that PORT is still waiting for Security to complete */
360     if (!p_port->in_use
361      || ((p_port->rfc.state != RFC_STATE_ORIG_WAIT_SEC_CHECK)
362       && (p_port->rfc.state != RFC_STATE_TERM_WAIT_SEC_CHECK)))
363         return;
364 
365     rfc_port_sm_execute ((tPORT *)p_ref_data, RFC_EVENT_SEC_COMPLETE, &res);
366 }
367 
368 
369 /*******************************************************************************
370 **
371 ** Function         rfc_port_closed
372 **
373 ** Description      The function is called when port is released based on the
374 **                  event received from the lower layer, typically L2CAP
375 **                  connection down, DISC, or DM frame.
376 **
377 ** Returns          void
378 **
379 *******************************************************************************/
rfc_port_closed(tPORT * p_port)380 void rfc_port_closed (tPORT *p_port)
381 {
382     tRFC_MCB *p_mcb = p_port->rfc.p_mcb;
383 
384     RFCOMM_TRACE_DEBUG ("rfc_port_closed");
385 
386     rfc_port_timer_stop (p_port);
387 
388     p_port->rfc.state = RFC_STATE_CLOSED;
389 
390     /* If multiplexer channel was up mark it as down */
391     if (p_mcb)
392     {
393         p_mcb->port_inx[p_port->dlci] = 0;
394 
395         /* If there are no more ports opened on this MCB release it */
396         rfc_check_mcb_active (p_mcb);
397     }
398 
399     /* Notify port that RFC connection is gone */
400     port_rfc_closed (p_port, PORT_CLOSED);
401 }
402 
403 /*******************************************************************************
404 **
405 ** Function         rfc_inc_credit
406 **
407 ** Description      The function is called when a credit is received in a UIH
408 **                  frame.  It increments the TX credit count, and if data
409 **                  flow had halted, it restarts it.
410 **
411 ** Returns          void
412 **
413 *******************************************************************************/
rfc_inc_credit(tPORT * p_port,UINT8 credit)414 void rfc_inc_credit (tPORT *p_port, UINT8 credit)
415 {
416     if (p_port->rfc.p_mcb->flow == PORT_FC_CREDIT)
417     {
418         p_port->credit_tx += credit;
419 
420         RFCOMM_TRACE_EVENT ("rfc_inc_credit:%d", p_port->credit_tx);
421 
422         if (p_port->tx.peer_fc == TRUE)
423             PORT_FlowInd(p_port->rfc.p_mcb, p_port->dlci, TRUE);
424     }
425 }
426 
427 /*******************************************************************************
428 **
429 ** Function         rfc_dec_credit
430 **
431 ** Description      The function is called when a UIH frame of user data is
432 **                  sent.  It decrements the credit count.  If credit count
433 **                  Reaches zero, peer_fc is set.
434 **
435 ** Returns          void
436 **
437 *******************************************************************************/
rfc_dec_credit(tPORT * p_port)438 void rfc_dec_credit (tPORT *p_port)
439 {
440     if (p_port->rfc.p_mcb->flow == PORT_FC_CREDIT)
441     {
442         if (p_port->credit_tx > 0)
443             p_port->credit_tx--;
444 
445         if (p_port->credit_tx == 0)
446             p_port->tx.peer_fc = TRUE;
447     }
448 }
449 
450 
451 /*******************************************************************************
452 **
453 ** Function         rfc_check_send_cmd
454 **
455 ** Description      This function is called to send an RFCOMM command message
456 **                  or to handle the RFCOMM command message queue.
457 **
458 ** Returns          void
459 **
460 *******************************************************************************/
rfc_check_send_cmd(tRFC_MCB * p_mcb,BT_HDR * p_buf)461 void rfc_check_send_cmd(tRFC_MCB *p_mcb, BT_HDR *p_buf)
462 {
463     BT_HDR  *p;
464 
465     /* if passed a buffer queue it */
466     if (p_buf != NULL)
467     {
468         GKI_enqueue(&p_mcb->cmd_q, p_buf);
469     }
470 
471     /* handle queue if L2CAP not congested */
472     while (p_mcb->l2cap_congested == FALSE)
473     {
474         if ((p = (BT_HDR *) GKI_dequeue(&p_mcb->cmd_q)) == NULL)
475         {
476             break;
477         }
478 
479 
480         L2CA_DataWrite (p_mcb->lcid, p);
481     }
482 }
483 
484 
485