1 /* 2 * Copyright (C) 2014 BlueKitchen GmbH 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 4. Any redistribution, use, or modification is done solely for 17 * personal benefit and not for any commercial purpose or for 18 * monetary gain. 19 * 20 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS 24 * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Please inquire about commercial licensing options at 34 * [email protected] 35 * 36 */ 37 38 #define __BTSTACK_FILE__ "rfcomm.c" 39 40 /* 41 * rfcomm.c 42 */ 43 44 #include <stdio.h> 45 #include <stdlib.h> 46 #include <string.h> // memcpy 47 #include <stdint.h> 48 49 #include "bluetooth_sdp.h" 50 #include "btstack_debug.h" 51 #include "btstack_event.h" 52 #include "btstack_memory.h" 53 #include "btstack_util.h" 54 #include "classic/core.h" 55 #include "classic/rfcomm.h" 56 #include "hci.h" 57 #include "hci_cmd.h" 58 #include "hci_dump.h" 59 #include "l2cap.h" 60 61 // workaround for missing PRIxPTR on mspgcc (16/20-bit MCU) 62 #ifndef PRIxPTR 63 #if defined(__MSP430X__) && defined(__MSP430X_LARGE__) 64 #define PRIxPTR "lx" 65 #else 66 #define PRIxPTR "x" 67 #endif 68 #endif 69 70 #define RFCOMM_MULIPLEXER_TIMEOUT_MS 60000 71 72 #define RFCOMM_CREDITS 10 73 74 // FCS calc 75 #define BT_RFCOMM_CODE_WORD 0xE0 // pol = x8+x2+x1+1 76 #define BT_RFCOMM_CRC_CHECK_LEN 3 77 #define BT_RFCOMM_UIHCRC_CHECK_LEN 2 78 79 80 typedef enum { 81 CH_EVT_RCVD_SABM = 1, 82 CH_EVT_RCVD_UA, 83 CH_EVT_RCVD_PN, 84 CH_EVT_RCVD_PN_RSP, 85 CH_EVT_RCVD_DISC, 86 CH_EVT_RCVD_DM, 87 CH_EVT_RCVD_MSC_CMD, 88 CH_EVT_RCVD_MSC_RSP, 89 CH_EVT_RCVD_NSC_RSP, 90 CH_EVT_RCVD_RLS_CMD, 91 CH_EVT_RCVD_RLS_RSP, 92 CH_EVT_RCVD_RPN_CMD, 93 CH_EVT_RCVD_RPN_REQ, 94 CH_EVT_RCVD_CREDITS, 95 CH_EVT_MULTIPLEXER_READY, 96 CH_EVT_READY_TO_SEND, 97 } RFCOMM_CHANNEL_EVENT; 98 99 typedef struct rfcomm_channel_event { 100 RFCOMM_CHANNEL_EVENT type; 101 uint16_t dummy; // force rfcomm_channel_event to be 2-byte aligned -> avoid -Wcast-align warning 102 } rfcomm_channel_event_t; 103 104 typedef struct rfcomm_channel_event_pn { 105 rfcomm_channel_event_t super; 106 uint16_t max_frame_size; 107 uint8_t priority; 108 uint8_t credits_outgoing; 109 } rfcomm_channel_event_pn_t; 110 111 typedef struct rfcomm_channel_event_rpn { 112 rfcomm_channel_event_t super; 113 rfcomm_rpn_data_t data; 114 } rfcomm_channel_event_rpn_t; 115 116 typedef struct rfcomm_channel_event_rls { 117 rfcomm_channel_event_t super; 118 uint8_t line_status; 119 } rfcomm_channel_event_rls_t; 120 121 typedef struct rfcomm_channel_event_msc { 122 rfcomm_channel_event_t super; 123 uint8_t modem_status; 124 } rfcomm_channel_event_msc_t; 125 126 127 // global rfcomm data 128 static uint16_t rfcomm_client_cid_generator; // used for client channel IDs 129 130 // linked lists for all 131 static btstack_linked_list_t rfcomm_multiplexers = NULL; 132 static btstack_linked_list_t rfcomm_channels = NULL; 133 static btstack_linked_list_t rfcomm_services = NULL; 134 135 static gap_security_level_t rfcomm_security_level; 136 137 static int rfcomm_channel_can_send(rfcomm_channel_t * channel); 138 static int rfcomm_channel_ready_for_open(rfcomm_channel_t *channel); 139 static int rfcomm_channel_ready_to_send(rfcomm_channel_t * channel); 140 static void rfcomm_channel_state_machine_with_channel(rfcomm_channel_t *channel, const rfcomm_channel_event_t *event); 141 static void rfcomm_channel_state_machine_with_dlci(rfcomm_multiplexer_t * multiplexer, uint8_t dlci, const rfcomm_channel_event_t *event); 142 static void rfcomm_emit_can_send_now(rfcomm_channel_t *channel); 143 static int rfcomm_multiplexer_ready_to_send(rfcomm_multiplexer_t * multiplexer); 144 static void rfcomm_multiplexer_state_machine(rfcomm_multiplexer_t * multiplexer, RFCOMM_MULTIPLEXER_EVENT event); 145 146 // MARK: RFCOMM CLIENT EVENTS 147 148 // data: event (8), len(8), address(48), channel (8), rfcomm_cid (16) 149 static void rfcomm_emit_connection_request(rfcomm_channel_t *channel) { 150 log_info("RFCOMM_EVENT_INCOMING_CONNECTION addr %s channel #%u cid 0x%02x", 151 bd_addr_to_str(channel->multiplexer->remote_addr), channel->dlci>>1, channel->rfcomm_cid); 152 uint8_t event[11]; 153 event[0] = RFCOMM_EVENT_INCOMING_CONNECTION; 154 event[1] = sizeof(event) - 2; 155 reverse_bd_addr(channel->multiplexer->remote_addr, &event[2]); 156 event[8] = channel->dlci >> 1; 157 little_endian_store_16(event, 9, channel->rfcomm_cid); 158 hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event)); 159 (channel->packet_handler)(HCI_EVENT_PACKET, 0, event, sizeof(event)); 160 } 161 162 // API Change: BTstack-0.3.50x uses 163 // data: event(8), len(8), status (8), address (48), server channel(8), rfcomm_cid(16), max frame size(16) 164 // next Cydia release will use SVN version of this 165 // data: event(8), len(8), status (8), address (48), handle (16), server channel(8), rfcomm_cid(16), max frame size(16) 166 static void rfcomm_emit_channel_opened(rfcomm_channel_t *channel, uint8_t status) { 167 log_info("RFCOMM_EVENT_CHANNEL_OPENED status 0x%x addr %s handle 0x%x channel #%u cid 0x%02x mtu %u", 168 status, bd_addr_to_str(channel->multiplexer->remote_addr), channel->multiplexer->con_handle, 169 channel->dlci>>1, channel->rfcomm_cid, channel->max_frame_size); 170 uint8_t event[18]; 171 uint8_t pos = 0; 172 event[pos++] = RFCOMM_EVENT_CHANNEL_OPENED; // 0 173 event[pos++] = sizeof(event) - 2; // 1 174 event[pos++] = status; // 2 175 reverse_bd_addr(channel->multiplexer->remote_addr, &event[pos]); pos += 6; // 3 176 little_endian_store_16(event, pos, channel->multiplexer->con_handle); pos += 2; // 9 177 event[pos++] = channel->dlci >> 1; // 11 178 little_endian_store_16(event, pos, channel->rfcomm_cid); pos += 2; // 12 - channel ID 179 little_endian_store_16(event, pos, channel->max_frame_size); pos += 2; // max frame size 180 event[pos++] = channel->service ? 1 : 0; // linked to service -> incoming 181 hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event)); 182 (channel->packet_handler)(HCI_EVENT_PACKET, 0, event, pos); 183 184 // if channel opened successfully, also send can send now if possible 185 if (status) return; 186 if (rfcomm_channel_can_send(channel)){ 187 rfcomm_emit_can_send_now(channel); 188 } 189 } 190 191 // data: event(8), len(8), rfcomm_cid(16) 192 static void rfcomm_emit_channel_closed(rfcomm_channel_t * channel) { 193 log_info("RFCOMM_EVENT_CHANNEL_CLOSED cid 0x%02x", channel->rfcomm_cid); 194 uint8_t event[4]; 195 event[0] = RFCOMM_EVENT_CHANNEL_CLOSED; 196 event[1] = sizeof(event) - 2; 197 little_endian_store_16(event, 2, channel->rfcomm_cid); 198 hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event)); 199 (channel->packet_handler)(HCI_EVENT_PACKET, 0, event, sizeof(event)); 200 } 201 202 static void rfcomm_emit_remote_line_status(rfcomm_channel_t *channel, uint8_t line_status){ 203 log_info("RFCOMM_EVENT_REMOTE_LINE_STATUS cid 0x%02x c, line status 0x%x", channel->rfcomm_cid, line_status); 204 uint8_t event[5]; 205 event[0] = RFCOMM_EVENT_REMOTE_LINE_STATUS; 206 event[1] = sizeof(event) - 2; 207 little_endian_store_16(event, 2, channel->rfcomm_cid); 208 event[4] = line_status; 209 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 210 (channel->packet_handler)(HCI_EVENT_PACKET, 0, event, sizeof(event)); 211 } 212 213 static void rfcomm_emit_port_configuration(rfcomm_channel_t *channel){ 214 // notify client about new settings 215 uint8_t event[2+sizeof(rfcomm_rpn_data_t)]; 216 event[0] = RFCOMM_EVENT_PORT_CONFIGURATION; 217 event[1] = sizeof(rfcomm_rpn_data_t); 218 memcpy(&event[2], (uint8_t*) &channel->rpn_data, sizeof(rfcomm_rpn_data_t)); 219 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 220 (channel->packet_handler)(HCI_EVENT_PACKET, channel->rfcomm_cid, event, sizeof(event)); 221 } 222 223 static void rfcomm_emit_can_send_now(rfcomm_channel_t *channel) { 224 log_debug("RFCOMM_EVENT_CHANNEL_CAN_SEND_NOW local_cid 0x%x", channel->rfcomm_cid); 225 uint8_t event[4]; 226 event[0] = RFCOMM_EVENT_CAN_SEND_NOW; 227 event[1] = sizeof(event) - 2; 228 little_endian_store_16(event, 2, channel->rfcomm_cid); 229 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 230 (channel->packet_handler)(HCI_EVENT_PACKET, channel->rfcomm_cid, event, sizeof(event)); 231 } 232 233 // MARK RFCOMM RPN DATA HELPER 234 static void rfcomm_rpn_data_set_defaults(rfcomm_rpn_data_t * rpn_data){ 235 rpn_data->baud_rate = RPN_BAUD_9600; /* 9600 bps */ 236 rpn_data->flags = 0x03; /* 8-n-1 */ 237 rpn_data->flow_control = 0; /* no flow control */ 238 rpn_data->xon = 0xd1; /* XON */ 239 rpn_data->xoff = 0xd3; /* XOFF */ 240 rpn_data->parameter_mask_0 = 0x7f; /* parameter mask, all values set */ 241 rpn_data->parameter_mask_1 = 0x3f; /* parameter mask, all values set */ 242 } 243 244 static void rfcomm_rpn_data_update(rfcomm_rpn_data_t * dest, rfcomm_rpn_data_t * src){ 245 if (src->parameter_mask_0 & RPN_PARAM_MASK_0_BAUD){ 246 dest->baud_rate = src->baud_rate; 247 } 248 if (src->parameter_mask_0 & RPN_PARAM_MASK_0_DATA_BITS){ 249 dest->flags = (dest->flags & 0xfc) | (src->flags & 0x03); 250 } 251 if (src->parameter_mask_0 & RPN_PARAM_MASK_0_STOP_BITS){ 252 dest->flags = (dest->flags & 0xfb) | (src->flags & 0x04); 253 } 254 if (src->parameter_mask_0 & RPN_PARAM_MASK_0_PARITY){ 255 dest->flags = (dest->flags & 0xf7) | (src->flags & 0x08); 256 } 257 if (src->parameter_mask_0 & RPN_PARAM_MASK_0_PARITY_TYPE){ 258 dest->flags = (dest->flags & 0xfc) | (src->flags & 0x30); 259 } 260 if (src->parameter_mask_0 & RPN_PARAM_MASK_0_XON_CHAR){ 261 dest->xon = src->xon; 262 } 263 if (src->parameter_mask_0 & RPN_PARAM_MASK_0_XOFF_CHAR){ 264 dest->xoff = src->xoff; 265 } 266 int i; 267 for (i=0; i < 6 ; i++){ 268 uint8_t mask = 1 << i; 269 if (src->parameter_mask_1 & mask){ 270 dest->flags = (dest->flags & ~mask) | (src->flags & mask); 271 } 272 } 273 // always copy parameter mask, too. informative for client, needed for response 274 dest->parameter_mask_0 = src->parameter_mask_0; 275 dest->parameter_mask_1 = src->parameter_mask_1; 276 } 277 // MARK: RFCOMM MULTIPLEXER HELPER 278 279 static uint16_t rfcomm_max_frame_size_for_l2cap_mtu(uint16_t l2cap_mtu){ 280 // Assume RFCOMM header without credits and 2 byte (14 bit) length field 281 uint16_t max_frame_size = l2cap_mtu - 5; 282 log_info("rfcomm_max_frame_size_for_l2cap_mtu: %u -> %u", l2cap_mtu, max_frame_size); 283 return max_frame_size; 284 } 285 286 static void rfcomm_multiplexer_initialize(rfcomm_multiplexer_t *multiplexer){ 287 288 memset(multiplexer, 0, sizeof(rfcomm_multiplexer_t)); 289 290 multiplexer->state = RFCOMM_MULTIPLEXER_CLOSED; 291 multiplexer->fcon = 1; 292 multiplexer->send_dm_for_dlci = 0; 293 multiplexer->max_frame_size = rfcomm_max_frame_size_for_l2cap_mtu(l2cap_max_mtu()); 294 multiplexer->test_data_len = 0; 295 multiplexer->nsc_command = 0; 296 } 297 298 static rfcomm_multiplexer_t * rfcomm_multiplexer_create_for_addr(bd_addr_t addr){ 299 300 // alloc structure 301 rfcomm_multiplexer_t * multiplexer = btstack_memory_rfcomm_multiplexer_get(); 302 if (!multiplexer) return NULL; 303 304 // fill in 305 rfcomm_multiplexer_initialize(multiplexer); 306 bd_addr_copy(multiplexer->remote_addr, addr); 307 308 // add to services list 309 btstack_linked_list_add(&rfcomm_multiplexers, (btstack_linked_item_t *) multiplexer); 310 311 return multiplexer; 312 } 313 314 static rfcomm_multiplexer_t * rfcomm_multiplexer_for_addr(bd_addr_t addr){ 315 btstack_linked_item_t *it; 316 for (it = (btstack_linked_item_t *) rfcomm_multiplexers; it ; it = it->next){ 317 rfcomm_multiplexer_t * multiplexer = ((rfcomm_multiplexer_t *) it); 318 // ignore multiplexer in shutdown 319 if (multiplexer->state == RFCOMM_MULTIPLEXER_SHUTTING_DOWN) continue; 320 if (bd_addr_cmp(addr, multiplexer->remote_addr) == 0) { 321 return multiplexer; 322 }; 323 } 324 return NULL; 325 } 326 327 static rfcomm_multiplexer_t * rfcomm_multiplexer_for_l2cap_cid(uint16_t l2cap_cid) { 328 btstack_linked_item_t *it; 329 for (it = (btstack_linked_item_t *) rfcomm_multiplexers; it ; it = it->next){ 330 rfcomm_multiplexer_t * multiplexer = ((rfcomm_multiplexer_t *) it); 331 if (multiplexer->l2cap_cid == l2cap_cid) { 332 return multiplexer; 333 }; 334 } 335 return NULL; 336 } 337 338 static int rfcomm_multiplexer_has_channels(rfcomm_multiplexer_t * multiplexer){ 339 btstack_linked_item_t *it; 340 for (it = (btstack_linked_item_t *) rfcomm_channels; it ; it = it->next){ 341 rfcomm_channel_t * channel = ((rfcomm_channel_t *) it); 342 if (channel->multiplexer == multiplexer) { 343 return 1; 344 } 345 } 346 return 0; 347 } 348 349 // MARK: RFCOMM CHANNEL HELPER 350 351 static void rfcomm_dump_channels(void){ 352 btstack_linked_item_t * it; 353 int channels = 0; 354 for (it = (btstack_linked_item_t *) rfcomm_channels; it ; it = it->next){ 355 rfcomm_channel_t * channel = (rfcomm_channel_t *) it; 356 log_info("Channel #%u: addr %p, state %u", channels, channel, channel->state); 357 channels++; 358 } 359 } 360 361 static void rfcomm_channel_initialize(rfcomm_channel_t *channel, rfcomm_multiplexer_t *multiplexer, 362 rfcomm_service_t *service, uint8_t server_channel){ 363 364 // don't use 0 as channel id 365 if (rfcomm_client_cid_generator == 0) ++rfcomm_client_cid_generator; 366 367 // setup channel 368 memset(channel, 0, sizeof(rfcomm_channel_t)); 369 370 // set defaults for port configuration (even for services) 371 rfcomm_rpn_data_set_defaults(&channel->rpn_data); 372 373 channel->state = RFCOMM_CHANNEL_CLOSED; 374 channel->state_var = RFCOMM_CHANNEL_STATE_VAR_NONE; 375 376 channel->multiplexer = multiplexer; 377 channel->rfcomm_cid = rfcomm_client_cid_generator++; 378 channel->max_frame_size = multiplexer->max_frame_size; 379 380 channel->credits_incoming = 0; 381 channel->credits_outgoing = 0; 382 383 // incoming flow control not active 384 channel->new_credits_incoming = RFCOMM_CREDITS; 385 channel->incoming_flow_control = 0; 386 387 channel->rls_line_status = RFCOMM_RLS_STATUS_INVALID; 388 389 channel->service = service; 390 if (service) { 391 // incoming connection 392 channel->dlci = (server_channel << 1) | multiplexer->outgoing; 393 if (channel->max_frame_size > service->max_frame_size) { 394 channel->max_frame_size = service->max_frame_size; 395 } 396 channel->incoming_flow_control = service->incoming_flow_control; 397 channel->new_credits_incoming = service->incoming_initial_credits; 398 channel->packet_handler = service->packet_handler; 399 } else { 400 // outgoing connection 401 channel->dlci = (server_channel << 1) | (multiplexer->outgoing ^ 1); 402 } 403 } 404 405 // service == NULL -> outgoing channel 406 static rfcomm_channel_t * rfcomm_channel_create(rfcomm_multiplexer_t * multiplexer, 407 rfcomm_service_t * service, uint8_t server_channel){ 408 409 log_info("rfcomm_channel_create for service %p, channel %u --- list of channels:", service, server_channel); 410 rfcomm_dump_channels(); 411 412 // alloc structure 413 rfcomm_channel_t * channel = btstack_memory_rfcomm_channel_get(); 414 if (!channel) return NULL; 415 416 // fill in 417 rfcomm_channel_initialize(channel, multiplexer, service, server_channel); 418 419 // add to services list 420 btstack_linked_list_add(&rfcomm_channels, (btstack_linked_item_t *) channel); 421 422 return channel; 423 } 424 425 static void rfcomm_notify_channel_can_send(void){ 426 btstack_linked_list_iterator_t it; 427 btstack_linked_list_iterator_init(&it, &rfcomm_channels); 428 while (btstack_linked_list_iterator_has_next(&it)){ 429 rfcomm_channel_t * channel = (rfcomm_channel_t *) btstack_linked_list_iterator_next(&it); 430 if (!channel->waiting_for_can_send_now) continue; // didn't try to send yet 431 if (!rfcomm_channel_can_send(channel)) continue; // or cannot yet either 432 433 channel->waiting_for_can_send_now = 0; 434 rfcomm_emit_can_send_now(channel); 435 } 436 } 437 438 static rfcomm_channel_t * rfcomm_channel_for_rfcomm_cid(uint16_t rfcomm_cid){ 439 btstack_linked_item_t *it; 440 for (it = (btstack_linked_item_t *) rfcomm_channels; it ; it = it->next){ 441 rfcomm_channel_t * channel = ((rfcomm_channel_t *) it); 442 if (channel->rfcomm_cid == rfcomm_cid) { 443 return channel; 444 }; 445 } 446 return NULL; 447 } 448 449 static rfcomm_channel_t * rfcomm_channel_for_multiplexer_and_dlci(rfcomm_multiplexer_t * multiplexer, uint8_t dlci){ 450 btstack_linked_item_t *it; 451 for (it = (btstack_linked_item_t *) rfcomm_channels; it ; it = it->next){ 452 rfcomm_channel_t * channel = ((rfcomm_channel_t *) it); 453 if (channel->dlci == dlci && channel->multiplexer == multiplexer) { 454 return channel; 455 }; 456 } 457 return NULL; 458 } 459 460 static rfcomm_service_t * rfcomm_service_for_channel(uint8_t server_channel){ 461 btstack_linked_item_t *it; 462 for (it = (btstack_linked_item_t *) rfcomm_services; it ; it = it->next){ 463 rfcomm_service_t * service = ((rfcomm_service_t *) it); 464 if ( service->server_channel == server_channel){ 465 return service; 466 }; 467 } 468 return NULL; 469 } 470 471 // MARK: RFCOMM SEND 472 473 /** 474 * @param credits - only used for RFCOMM flow control in UIH wiht P/F = 1 475 */ 476 static int rfcomm_send_packet_for_multiplexer(rfcomm_multiplexer_t *multiplexer, uint8_t address, uint8_t control, uint8_t credits, uint8_t *data, uint16_t len){ 477 478 if (!l2cap_can_send_packet_now(multiplexer->l2cap_cid)) return BTSTACK_ACL_BUFFERS_FULL; 479 480 l2cap_reserve_packet_buffer(); 481 uint8_t * rfcomm_out_buffer = l2cap_get_outgoing_buffer(); 482 483 uint16_t pos = 0; 484 uint8_t crc_fields = 3; 485 486 rfcomm_out_buffer[pos++] = address; 487 rfcomm_out_buffer[pos++] = control; 488 489 // length field can be 1 or 2 octets 490 if (len < 128){ 491 rfcomm_out_buffer[pos++] = (len << 1)| 1; // bits 0-6 492 } else { 493 rfcomm_out_buffer[pos++] = (len & 0x7f) << 1; // bits 0-6 494 rfcomm_out_buffer[pos++] = len >> 7; // bits 7-14 495 crc_fields++; 496 } 497 498 // add credits for UIH frames when PF bit is set 499 if (control == BT_RFCOMM_UIH_PF){ 500 rfcomm_out_buffer[pos++] = credits; 501 } 502 503 // copy actual data 504 if (len) { 505 memcpy(&rfcomm_out_buffer[pos], data, len); 506 pos += len; 507 } 508 509 // UIH frames only calc FCS over address + control (5.1.1) 510 if ((control & 0xef) == BT_RFCOMM_UIH){ 511 crc_fields = 2; 512 } 513 rfcomm_out_buffer[pos++] = btstack_crc8_calc(rfcomm_out_buffer, crc_fields); // calc fcs 514 515 int err = l2cap_send_prepared(multiplexer->l2cap_cid, pos); 516 517 return err; 518 } 519 520 // simplified version of rfcomm_send_packet_for_multiplexer for prepared rfcomm packet (UIH, 2 byte len, no credits) 521 static int rfcomm_send_uih_prepared(rfcomm_multiplexer_t *multiplexer, uint8_t dlci, uint16_t len){ 522 523 uint8_t address = (1 << 0) | (multiplexer->outgoing << 1) | (dlci << 2); 524 uint8_t control = BT_RFCOMM_UIH; 525 526 uint8_t * rfcomm_out_buffer = l2cap_get_outgoing_buffer(); 527 528 uint16_t pos = 0; 529 rfcomm_out_buffer[pos++] = address; 530 rfcomm_out_buffer[pos++] = control; 531 rfcomm_out_buffer[pos++] = (len & 0x7f) << 1; // bits 0-6 532 rfcomm_out_buffer[pos++] = len >> 7; // bits 7-14 533 534 // actual data is already in place 535 pos += len; 536 537 // UIH frames only calc FCS over address + control (5.1.1) 538 rfcomm_out_buffer[pos++] = btstack_crc8_calc(rfcomm_out_buffer, 2); // calc fcs 539 540 int err = l2cap_send_prepared(multiplexer->l2cap_cid, pos); 541 542 return err; 543 } 544 545 // C/R Flag in Address 546 // - terms: initiator = station that creates multiplexer with SABM 547 // - terms: responder = station that responds to multiplexer setup with UA 548 // "For SABM, UA, DM and DISC frames C/R bit is set according to Table 1 in GSM 07.10, section 5.2.1.2" 549 // - command initiator = 1 /response responder = 1 550 // - command responder = 0 /response initiator = 0 551 // "For UIH frames, the C/R bit is always set according to section 5.4.3.1 in GSM 07.10. 552 // This applies independently of what is contained wthin the UIH frames, either data or control messages." 553 // - c/r = 1 for frames by initiating station, 0 = for frames by responding station 554 555 // C/R Flag in Message 556 // "In the message level, the C/R bit in the command type field is set as stated in section 5.4.6.2 in GSM 07.10." 557 // - If the C/R bit is set to 1 the message is a command 558 // - if it is set to 0 the message is a response. 559 560 // temp/old messge construction 561 562 // new object oriented version 563 static int rfcomm_send_sabm(rfcomm_multiplexer_t *multiplexer, uint8_t dlci){ 564 uint8_t address = (1 << 0) | (multiplexer->outgoing << 1) | (dlci << 2); // command 565 return rfcomm_send_packet_for_multiplexer(multiplexer, address, BT_RFCOMM_SABM, 0, NULL, 0); 566 } 567 568 static int rfcomm_send_disc(rfcomm_multiplexer_t *multiplexer, uint8_t dlci){ 569 uint8_t address = (1 << 0) | (multiplexer->outgoing << 1) | (dlci << 2); // command 570 return rfcomm_send_packet_for_multiplexer(multiplexer, address, BT_RFCOMM_DISC, 0, NULL, 0); 571 } 572 573 static int rfcomm_send_ua(rfcomm_multiplexer_t *multiplexer, uint8_t dlci){ 574 uint8_t address = (1 << 0) | ((multiplexer->outgoing ^ 1) << 1) | (dlci << 2); // response 575 return rfcomm_send_packet_for_multiplexer(multiplexer, address, BT_RFCOMM_UA, 0, NULL, 0); 576 } 577 578 static int rfcomm_send_dm_pf(rfcomm_multiplexer_t *multiplexer, uint8_t dlci){ 579 uint8_t address = (1 << 0) | ((multiplexer->outgoing ^ 1) << 1) | (dlci << 2); // response 580 return rfcomm_send_packet_for_multiplexer(multiplexer, address, BT_RFCOMM_DM_PF, 0, NULL, 0); 581 } 582 583 static int rfcomm_send_uih_fc_rsp(rfcomm_multiplexer_t *multiplexer, uint8_t fcon) { 584 uint8_t address = (1 << 0) | (multiplexer->outgoing<< 1); 585 uint8_t payload[2]; 586 uint8_t pos = 0; 587 payload[pos++] = fcon ? BT_RFCOMM_FCON_RSP : BT_RFCOMM_FCOFF_RSP; 588 payload[pos++] = (0 << 1) | 1; // len 589 return rfcomm_send_packet_for_multiplexer(multiplexer, address, BT_RFCOMM_UIH, 0, (uint8_t *) payload, pos); 590 } 591 592 // static int rfcomm_send_uih_test_cmd(rfcomm_multiplexer_t *multiplexer, uint8_t * data, uint16_t len) { 593 // uint8_t address = (1 << 0) | (multiplexer->outgoing << 1); 594 // uint8_t payload[2+len]; 595 // uint8_t pos = 0; 596 // payload[pos++] = BT_RFCOMM_TEST_CMD; 597 // payload[pos++] = (len + 1) << 1 | 1; // len 598 // memcpy(&payload[pos], data, len); 599 // pos += len; 600 // return rfcomm_send_packet_for_multiplexer(multiplexer, address, BT_RFCOMM_UIH, 0, (uint8_t *) payload, pos); 601 // } 602 603 static int rfcomm_send_uih_test_rsp(rfcomm_multiplexer_t *multiplexer, uint8_t * data, uint16_t len) { 604 uint8_t address = (1 << 0) | (multiplexer->outgoing << 1); 605 uint8_t payload[2+RFCOMM_TEST_DATA_MAX_LEN]; 606 uint8_t pos = 0; 607 payload[pos++] = BT_RFCOMM_TEST_RSP; 608 if (len > RFCOMM_TEST_DATA_MAX_LEN) { 609 len = RFCOMM_TEST_DATA_MAX_LEN; 610 } 611 payload[pos++] = (len << 1) | 1; // len 612 memcpy(&payload[pos], data, len); 613 pos += len; 614 return rfcomm_send_packet_for_multiplexer(multiplexer, address, BT_RFCOMM_UIH, 0, (uint8_t *) payload, pos); 615 } 616 617 static int rfcomm_send_uih_msc_cmd(rfcomm_multiplexer_t *multiplexer, uint8_t dlci, uint8_t signals) { 618 uint8_t address = (1 << 0) | (multiplexer->outgoing << 1); 619 uint8_t payload[4]; 620 uint8_t pos = 0; 621 payload[pos++] = BT_RFCOMM_MSC_CMD; 622 payload[pos++] = (2 << 1) | 1; // len 623 payload[pos++] = (1 << 0) | (1 << 1) | (dlci << 2); // CMD => C/R = 1 624 payload[pos++] = signals; 625 return rfcomm_send_packet_for_multiplexer(multiplexer, address, BT_RFCOMM_UIH, 0, (uint8_t *) payload, pos); 626 } 627 628 static int rfcomm_send_uih_msc_rsp(rfcomm_multiplexer_t *multiplexer, uint8_t dlci, uint8_t signals) { 629 uint8_t address = (1 << 0) | (multiplexer->outgoing<< 1); 630 uint8_t payload[4]; 631 uint8_t pos = 0; 632 payload[pos++] = BT_RFCOMM_MSC_RSP; 633 payload[pos++] = (2 << 1) | 1; // len 634 payload[pos++] = (1 << 0) | (1 << 1) | (dlci << 2); // CMD => C/R = 1 635 payload[pos++] = signals; 636 return rfcomm_send_packet_for_multiplexer(multiplexer, address, BT_RFCOMM_UIH, 0, (uint8_t *) payload, pos); 637 } 638 639 static int rfcomm_send_uih_nsc_rsp(rfcomm_multiplexer_t *multiplexer, uint8_t command) { 640 uint8_t address = (1 << 0) | (multiplexer->outgoing<< 1); 641 uint8_t payload[3]; 642 uint8_t pos = 0; 643 payload[pos++] = BT_RFCOMM_NSC_RSP; 644 payload[pos++] = (1 << 1) | 1; // len 645 payload[pos++] = command; 646 return rfcomm_send_packet_for_multiplexer(multiplexer, address, BT_RFCOMM_UIH, 0, (uint8_t *) payload, pos); 647 } 648 649 static int rfcomm_send_uih_pn_command(rfcomm_multiplexer_t *multiplexer, uint8_t dlci, uint16_t max_frame_size){ 650 uint8_t payload[10]; 651 uint8_t address = (1 << 0) | (multiplexer->outgoing << 1); 652 uint8_t pos = 0; 653 payload[pos++] = BT_RFCOMM_PN_CMD; 654 payload[pos++] = (8 << 1) | 1; // len 655 payload[pos++] = dlci; 656 payload[pos++] = 0xf0; // pre-defined for Bluetooth, see 5.5.3 of TS 07.10 Adaption for RFCOMM 657 payload[pos++] = 0; // priority 658 payload[pos++] = 0; // max 60 seconds ack 659 payload[pos++] = max_frame_size & 0xff; // max framesize low 660 payload[pos++] = max_frame_size >> 8; // max framesize high 661 payload[pos++] = 0x00; // number of retransmissions 662 payload[pos++] = 0x00; // (unused error recovery window) initial number of credits 663 return rfcomm_send_packet_for_multiplexer(multiplexer, address, BT_RFCOMM_UIH, 0, (uint8_t *) payload, pos); 664 } 665 666 // "The response may not change the DLCI, the priority, the convergence layer, or the timer value." rfcomm_tutorial.pdf 667 static int rfcomm_send_uih_pn_response(rfcomm_multiplexer_t *multiplexer, uint8_t dlci, 668 uint8_t priority, uint16_t max_frame_size){ 669 uint8_t payload[10]; 670 uint8_t address = (1 << 0) | (multiplexer->outgoing << 1); 671 uint8_t pos = 0; 672 payload[pos++] = BT_RFCOMM_PN_RSP; 673 payload[pos++] = (8 << 1) | 1; // len 674 payload[pos++] = dlci; 675 payload[pos++] = 0xe0; // pre defined for Bluetooth, see 5.5.3 of TS 07.10 Adaption for RFCOMM 676 payload[pos++] = priority; // priority 677 payload[pos++] = 0; // max 60 seconds ack 678 payload[pos++] = max_frame_size & 0xff; // max framesize low 679 payload[pos++] = max_frame_size >> 8; // max framesize high 680 payload[pos++] = 0x00; // number of retransmissions 681 payload[pos++] = 0x00; // (unused error recovery window) initial number of credits 682 return rfcomm_send_packet_for_multiplexer(multiplexer, address, BT_RFCOMM_UIH, 0, (uint8_t *) payload, pos); 683 } 684 685 static int rfcomm_send_uih_rls_cmd(rfcomm_multiplexer_t *multiplexer, uint8_t dlci, uint8_t line_status) { 686 uint8_t address = (1 << 0) | (multiplexer->outgoing << 1); 687 uint8_t payload[4]; 688 uint8_t pos = 0; 689 payload[pos++] = BT_RFCOMM_RLS_CMD; 690 payload[pos++] = (2 << 1) | 1; // len 691 payload[pos++] = (1 << 0) | (1 << 1) | (dlci << 2); // CMD => C/R = 1 692 payload[pos++] = line_status; 693 return rfcomm_send_packet_for_multiplexer(multiplexer, address, BT_RFCOMM_UIH, 0, (uint8_t *) payload, pos); 694 } 695 696 static int rfcomm_send_uih_rls_rsp(rfcomm_multiplexer_t *multiplexer, uint8_t dlci, uint8_t line_status) { 697 uint8_t address = (1 << 0) | (multiplexer->outgoing << 1); 698 uint8_t payload[4]; 699 uint8_t pos = 0; 700 payload[pos++] = BT_RFCOMM_RLS_RSP; 701 payload[pos++] = (2 << 1) | 1; // len 702 payload[pos++] = (1 << 0) | (1 << 1) | (dlci << 2); // CMD => C/R = 1 703 payload[pos++] = line_status; 704 return rfcomm_send_packet_for_multiplexer(multiplexer, address, BT_RFCOMM_UIH, 0, (uint8_t *) payload, pos); 705 } 706 707 static int rfcomm_send_uih_rpn_cmd(rfcomm_multiplexer_t *multiplexer, uint8_t dlci, rfcomm_rpn_data_t *rpn_data) { 708 uint8_t payload[10]; 709 uint8_t address = (1 << 0) | (multiplexer->outgoing << 1); 710 uint8_t pos = 0; 711 payload[pos++] = BT_RFCOMM_RPN_CMD; 712 payload[pos++] = (8 << 1) | 1; // len 713 payload[pos++] = (1 << 0) | (1 << 1) | (dlci << 2); // CMD => C/R = 1 714 payload[pos++] = rpn_data->baud_rate; 715 payload[pos++] = rpn_data->flags; 716 payload[pos++] = rpn_data->flow_control; 717 payload[pos++] = rpn_data->xon; 718 payload[pos++] = rpn_data->xoff; 719 payload[pos++] = rpn_data->parameter_mask_0; 720 payload[pos++] = rpn_data->parameter_mask_1; 721 return rfcomm_send_packet_for_multiplexer(multiplexer, address, BT_RFCOMM_UIH, 0, (uint8_t *) payload, pos); 722 } 723 724 static int rfcomm_send_uih_rpn_req(rfcomm_multiplexer_t *multiplexer, uint8_t dlci) { 725 uint8_t payload[3]; 726 uint8_t address = (1 << 0) | (multiplexer->outgoing << 1); 727 uint8_t pos = 0; 728 payload[pos++] = BT_RFCOMM_RPN_CMD; 729 payload[pos++] = (1 << 1) | 1; // len 730 payload[pos++] = (1 << 0) | (1 << 1) | (dlci << 2); // CMD => C/R = 1 731 return rfcomm_send_packet_for_multiplexer(multiplexer, address, BT_RFCOMM_UIH, 0, (uint8_t *) payload, pos); 732 } 733 734 static int rfcomm_send_uih_rpn_rsp(rfcomm_multiplexer_t *multiplexer, uint8_t dlci, rfcomm_rpn_data_t *rpn_data) { 735 uint8_t payload[10]; 736 uint8_t address = (1 << 0) | (multiplexer->outgoing << 1); 737 uint8_t pos = 0; 738 payload[pos++] = BT_RFCOMM_RPN_RSP; 739 payload[pos++] = (8 << 1) | 1; // len 740 payload[pos++] = (1 << 0) | (1 << 1) | (dlci << 2); // CMD => C/R = 1 741 payload[pos++] = rpn_data->baud_rate; 742 payload[pos++] = rpn_data->flags; 743 payload[pos++] = rpn_data->flow_control; 744 payload[pos++] = rpn_data->xon; 745 payload[pos++] = rpn_data->xoff; 746 payload[pos++] = rpn_data->parameter_mask_0; 747 payload[pos++] = rpn_data->parameter_mask_1; 748 return rfcomm_send_packet_for_multiplexer(multiplexer, address, BT_RFCOMM_UIH, 0, (uint8_t *) payload, pos); 749 } 750 751 static void rfcomm_send_uih_credits(rfcomm_multiplexer_t *multiplexer, uint8_t dlci, uint8_t credits){ 752 uint8_t address = (1 << 0) | (multiplexer->outgoing << 1) | (dlci << 2); 753 rfcomm_send_packet_for_multiplexer(multiplexer, address, BT_RFCOMM_UIH_PF, credits, NULL, 0); 754 } 755 756 // MARK: RFCOMM MULTIPLEXER 757 static void rfcomm_multiplexer_stop_timer(rfcomm_multiplexer_t * multiplexer){ 758 if (multiplexer->timer_active) { 759 btstack_run_loop_remove_timer(&multiplexer->timer); 760 multiplexer->timer_active = 0; 761 } 762 } 763 static void rfcomm_multiplexer_free(rfcomm_multiplexer_t * multiplexer){ 764 btstack_linked_list_remove( &rfcomm_multiplexers, (btstack_linked_item_t *) multiplexer); 765 btstack_memory_rfcomm_multiplexer_free(multiplexer); 766 } 767 768 static void rfcomm_multiplexer_finalize(rfcomm_multiplexer_t * multiplexer){ 769 // remove (potential) timer 770 rfcomm_multiplexer_stop_timer(multiplexer); 771 772 // close and remove all channels 773 btstack_linked_item_t *it = (btstack_linked_item_t *) &rfcomm_channels; 774 while (it->next){ 775 rfcomm_channel_t * channel = (rfcomm_channel_t *) it->next; 776 if (channel->multiplexer == multiplexer) { 777 // emit appropriate events 778 switch(channel->state){ 779 case RFCOMM_CHANNEL_OPEN: 780 case RFCOMM_CHANNEL_W4_UA_AFTER_DISC: 781 rfcomm_emit_channel_closed(channel); 782 break; 783 case RFCOMM_CHANNEL_SEND_UA_AFTER_DISC: 784 // remote didn't wait until we send the UA disc 785 break; 786 default: 787 rfcomm_emit_channel_opened(channel, RFCOMM_MULTIPLEXER_STOPPED); 788 break; 789 } 790 // remove from list 791 it->next = it->next->next; 792 // free channel struct 793 btstack_memory_rfcomm_channel_free(channel); 794 } else { 795 it = it->next; 796 } 797 } 798 799 // remove mutliplexer 800 rfcomm_multiplexer_free(multiplexer); 801 } 802 803 static void rfcomm_multiplexer_timer_handler(btstack_timer_source_t *timer){ 804 rfcomm_multiplexer_t * multiplexer = (rfcomm_multiplexer_t*) btstack_run_loop_get_timer_context(timer); 805 if (rfcomm_multiplexer_has_channels(multiplexer)) return; 806 807 log_info("rfcomm_multiplexer_timer_handler timeout: shutting down multiplexer! (no channels)"); 808 uint16_t l2cap_cid = multiplexer->l2cap_cid; 809 rfcomm_multiplexer_finalize(multiplexer); 810 l2cap_disconnect(l2cap_cid, 0x13); 811 } 812 813 static void rfcomm_multiplexer_prepare_idle_timer(rfcomm_multiplexer_t * multiplexer){ 814 if (multiplexer->timer_active) { 815 btstack_run_loop_remove_timer(&multiplexer->timer); 816 multiplexer->timer_active = 0; 817 } 818 if (rfcomm_multiplexer_has_channels(multiplexer)) return; 819 820 // start idle timer for multiplexer timeout check as there are no rfcomm channels yet 821 btstack_run_loop_set_timer(&multiplexer->timer, RFCOMM_MULIPLEXER_TIMEOUT_MS); 822 btstack_run_loop_set_timer_handler(&multiplexer->timer, rfcomm_multiplexer_timer_handler); 823 btstack_run_loop_set_timer_context(&multiplexer->timer, multiplexer); 824 btstack_run_loop_add_timer(&multiplexer->timer); 825 multiplexer->timer_active = 1; 826 } 827 828 static void rfcomm_multiplexer_opened(rfcomm_multiplexer_t *multiplexer){ 829 log_info("Multiplexer up and running"); 830 multiplexer->state = RFCOMM_MULTIPLEXER_OPEN; 831 832 const rfcomm_channel_event_t event = { CH_EVT_MULTIPLEXER_READY, 0}; 833 834 // transition of channels that wait for multiplexer 835 btstack_linked_item_t *it; 836 for (it = (btstack_linked_item_t *) rfcomm_channels; it ; it = it->next){ 837 rfcomm_channel_t * channel = ((rfcomm_channel_t *) it); 838 if (channel->multiplexer != multiplexer) continue; 839 rfcomm_channel_state_machine_with_channel(channel, &event); 840 if (rfcomm_channel_ready_to_send(channel)){ 841 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 842 } 843 } 844 rfcomm_multiplexer_prepare_idle_timer(multiplexer); 845 846 // request can send now for multiplexer if ready 847 if (rfcomm_multiplexer_ready_to_send(multiplexer)){ 848 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 849 } 850 } 851 852 static void rfcomm_handle_can_send_now(uint16_t l2cap_cid){ 853 854 log_debug("rfcomm_handle_can_send_now enter: %u", l2cap_cid); 855 856 btstack_linked_list_iterator_t it; 857 int token_consumed = 0; 858 859 // forward token to multiplexer 860 btstack_linked_list_iterator_init(&it, &rfcomm_multiplexers); 861 while (!token_consumed && btstack_linked_list_iterator_has_next(&it)){ 862 rfcomm_multiplexer_t * multiplexer = (rfcomm_multiplexer_t *) btstack_linked_list_iterator_next(&it); 863 if (multiplexer->l2cap_cid != l2cap_cid) continue; 864 if (rfcomm_multiplexer_ready_to_send(multiplexer)){ 865 log_debug("rfcomm_handle_can_send_now enter: multiplexer token"); 866 token_consumed = 1; 867 rfcomm_multiplexer_state_machine(multiplexer, MULT_EV_READY_TO_SEND); 868 } 869 } 870 871 // forward token to channel state machine 872 btstack_linked_list_iterator_init(&it, &rfcomm_channels); 873 while (!token_consumed && btstack_linked_list_iterator_has_next(&it)){ 874 rfcomm_channel_t * channel = (rfcomm_channel_t *) btstack_linked_list_iterator_next(&it); 875 if (channel->multiplexer->l2cap_cid != l2cap_cid) continue; 876 // channel state machine 877 if (rfcomm_channel_ready_to_send(channel)){ 878 log_debug("rfcomm_handle_can_send_now enter: channel token"); 879 token_consumed = 1; 880 const rfcomm_channel_event_t event = { CH_EVT_READY_TO_SEND, 0 }; 881 rfcomm_channel_state_machine_with_channel(channel, &event); 882 } 883 } 884 885 // forward token to client 886 btstack_linked_list_iterator_init(&it, &rfcomm_channels); 887 while (!token_consumed && btstack_linked_list_iterator_has_next(&it)){ 888 rfcomm_channel_t * channel = (rfcomm_channel_t *) btstack_linked_list_iterator_next(&it); 889 if (channel->multiplexer->l2cap_cid != l2cap_cid) continue; 890 // client waiting for can send now 891 if (!channel->waiting_for_can_send_now) continue; 892 if ((channel->multiplexer->fcon & 1) == 0) continue; 893 if (!channel->credits_outgoing){ 894 log_debug("rfcomm_handle_can_send_now waiting to send but no credits (ignore)"); 895 continue; 896 } 897 898 log_debug("rfcomm_handle_can_send_now enter: client token"); 899 token_consumed = 1; 900 channel->waiting_for_can_send_now = 0; 901 rfcomm_emit_can_send_now(channel); 902 } 903 904 // if token was consumed, request another one 905 if (token_consumed) { 906 l2cap_request_can_send_now_event(l2cap_cid); 907 } 908 909 log_debug("rfcomm_handle_can_send_now exit"); 910 } 911 912 static void rfcomm_multiplexer_set_state_and_request_can_send_now_event(rfcomm_multiplexer_t * multiplexer, RFCOMM_MULTIPLEXER_STATE state){ 913 multiplexer->state = state; 914 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 915 } 916 917 /** 918 * @return handled packet 919 */ 920 static int rfcomm_hci_event_handler(uint8_t *packet, uint16_t size){ 921 922 UNUSED(size); // ok: handling own l2cap events 923 924 bd_addr_t event_addr; 925 uint16_t psm; 926 uint16_t l2cap_cid; 927 hci_con_handle_t con_handle; 928 rfcomm_multiplexer_t *multiplexer = NULL; 929 uint8_t status; 930 931 switch (hci_event_packet_get_type(packet)) { 932 933 // accept incoming rfcomm connection if no multiplexer exists yet 934 case L2CAP_EVENT_INCOMING_CONNECTION: 935 // data: event(8), len(8), address(48), handle (16), psm (16), source cid(16) dest cid(16) 936 reverse_bd_addr(&packet[2], event_addr); 937 con_handle = little_endian_read_16(packet, 8); 938 psm = little_endian_read_16(packet, 10); 939 l2cap_cid = little_endian_read_16(packet, 12); 940 941 if (psm != BLUETOOTH_PROTOCOL_RFCOMM) break; 942 943 multiplexer = rfcomm_multiplexer_for_addr(event_addr); 944 945 if (multiplexer) { 946 log_info("INCOMING_CONNECTION (l2cap_cid 0x%02x) for BLUETOOTH_PROTOCOL_RFCOMM => decline - multiplexer already exists", l2cap_cid); 947 l2cap_decline_connection(l2cap_cid); 948 return 1; 949 } 950 951 // create and inititialize new multiplexer instance (incoming) 952 multiplexer = rfcomm_multiplexer_create_for_addr(event_addr); 953 if (!multiplexer){ 954 log_info("INCOMING_CONNECTION (l2cap_cid 0x%02x) for BLUETOOTH_PROTOCOL_RFCOMM => decline - no memory left", l2cap_cid); 955 l2cap_decline_connection(l2cap_cid); 956 return 1; 957 } 958 959 multiplexer->con_handle = con_handle; 960 multiplexer->l2cap_cid = l2cap_cid; 961 // 962 multiplexer->state = RFCOMM_MULTIPLEXER_W4_SABM_0; 963 log_info("L2CAP_EVENT_INCOMING_CONNECTION (l2cap_cid 0x%02x) for BLUETOOTH_PROTOCOL_RFCOMM => accept", l2cap_cid); 964 l2cap_accept_connection(l2cap_cid); 965 return 1; 966 967 // l2cap connection opened -> store l2cap_cid, remote_addr 968 case L2CAP_EVENT_CHANNEL_OPENED: 969 970 if (little_endian_read_16(packet, 11) != BLUETOOTH_PROTOCOL_RFCOMM) break; 971 972 status = packet[2]; 973 log_info("L2CAP_EVENT_CHANNEL_OPENED for BLUETOOTH_PROTOCOL_RFCOMM, status %u", status); 974 975 // get multiplexer for remote addr 976 con_handle = little_endian_read_16(packet, 9); 977 l2cap_cid = little_endian_read_16(packet, 13); 978 reverse_bd_addr(&packet[3], event_addr); 979 multiplexer = rfcomm_multiplexer_for_addr(event_addr); 980 if (!multiplexer) { 981 log_error("L2CAP_EVENT_CHANNEL_OPENED but no multiplexer prepared"); 982 return 1; 983 } 984 985 // on l2cap open error discard everything 986 if (status){ 987 988 // remove (potential) timer 989 rfcomm_multiplexer_stop_timer(multiplexer); 990 991 // mark multiplexer as shutting down 992 multiplexer->state = RFCOMM_MULTIPLEXER_SHUTTING_DOWN; 993 994 // emit rfcomm_channel_opened with status and free channel 995 // note: repeatedly go over list until full iteration causes no further change 996 int done; 997 do { 998 done = 1; 999 btstack_linked_item_t * it = (btstack_linked_item_t *) &rfcomm_channels; 1000 while (it->next) { 1001 rfcomm_channel_t * channel = (rfcomm_channel_t *) it->next; 1002 if (channel->multiplexer == multiplexer){ 1003 done = 0; 1004 rfcomm_emit_channel_opened(channel, status); 1005 btstack_linked_list_remove(&rfcomm_channels, (btstack_linked_item_t *) channel); 1006 btstack_memory_rfcomm_channel_free(channel); 1007 break; 1008 } else { 1009 it = it->next; 1010 } 1011 } 1012 } while (!done); 1013 1014 // free multiplexer 1015 rfcomm_multiplexer_free(multiplexer); 1016 return 1; 1017 } 1018 1019 // following could be: rfcom_multiplexer_state_machein(..., EVENT_L2CAP_OPENED) 1020 1021 if (multiplexer->state == RFCOMM_MULTIPLEXER_W4_CONNECT) { 1022 log_info("L2CAP_EVENT_CHANNEL_OPENED: outgoing connection"); 1023 // wrong remote addr 1024 if (bd_addr_cmp(event_addr, multiplexer->remote_addr)) break; 1025 multiplexer->l2cap_cid = l2cap_cid; 1026 multiplexer->con_handle = con_handle; 1027 // send SABM #0 1028 rfcomm_multiplexer_set_state_and_request_can_send_now_event(multiplexer, RFCOMM_MULTIPLEXER_SEND_SABM_0); 1029 1030 } else { // multiplexer->state == RFCOMM_MULTIPLEXER_W4_SABM_0 1031 1032 // set max frame size based on l2cap MTU 1033 multiplexer->max_frame_size = rfcomm_max_frame_size_for_l2cap_mtu(little_endian_read_16(packet, 17)); 1034 } 1035 return 1; 1036 1037 // l2cap disconnect -> state = RFCOMM_MULTIPLEXER_CLOSED; 1038 1039 // Notify channel packet handler if they can send now 1040 case L2CAP_EVENT_CAN_SEND_NOW: 1041 l2cap_cid = l2cap_event_can_send_now_get_local_cid(packet); 1042 rfcomm_handle_can_send_now(l2cap_cid); 1043 return 1; 1044 1045 case L2CAP_EVENT_CHANNEL_CLOSED: 1046 // data: event (8), len(8), channel (16) 1047 l2cap_cid = little_endian_read_16(packet, 2); 1048 multiplexer = rfcomm_multiplexer_for_l2cap_cid(l2cap_cid); 1049 log_info("L2CAP_EVENT_CHANNEL_CLOSED cid 0x%0x, mult %p", l2cap_cid, multiplexer); 1050 if (!multiplexer) break; 1051 log_info("L2CAP_EVENT_CHANNEL_CLOSED state %u", multiplexer->state); 1052 // no need to call l2cap_disconnect here, as it's already closed 1053 rfcomm_multiplexer_finalize(multiplexer); 1054 return 1; 1055 1056 default: 1057 break; 1058 } 1059 return 0; 1060 } 1061 1062 static int rfcomm_multiplexer_l2cap_packet_handler(uint16_t channel, uint8_t *packet, uint16_t size){ 1063 // get or create a multiplexer for a certain device 1064 rfcomm_multiplexer_t *multiplexer = rfcomm_multiplexer_for_l2cap_cid(channel); 1065 if (!multiplexer) return 0; 1066 1067 uint16_t l2cap_cid = multiplexer->l2cap_cid; 1068 1069 // but only care for multiplexer control channel 1070 uint8_t frame_dlci = packet[0] >> 2; 1071 if (frame_dlci) return 0; 1072 const uint8_t length_offset = (packet[2] & 1) ^ 1; // to be used for pos >= 3 1073 const uint8_t credit_offset = ((packet[1] & BT_RFCOMM_UIH_PF) == BT_RFCOMM_UIH_PF) ? 1 : 0; // credits for uih_pf frames 1074 const uint8_t payload_offset = 3 + length_offset + credit_offset; 1075 switch (packet[1]){ 1076 1077 case BT_RFCOMM_SABM: 1078 if (multiplexer->state == RFCOMM_MULTIPLEXER_W4_SABM_0){ 1079 log_info("Received SABM #0"); 1080 multiplexer->outgoing = 0; 1081 rfcomm_multiplexer_set_state_and_request_can_send_now_event(multiplexer, RFCOMM_MULTIPLEXER_SEND_UA_0); 1082 return 1; 1083 } 1084 break; 1085 1086 case BT_RFCOMM_UA: 1087 if (multiplexer->state == RFCOMM_MULTIPLEXER_W4_UA_0) { 1088 // UA #0 -> send UA #0, state = RFCOMM_MULTIPLEXER_OPEN 1089 log_info("Received UA #0 "); 1090 rfcomm_multiplexer_opened(multiplexer); 1091 return 1; 1092 } 1093 break; 1094 1095 case BT_RFCOMM_DISC: 1096 // DISC #0 -> send UA #0, close multiplexer 1097 log_info("Received DISC #0, (ougoing = %u)", multiplexer->outgoing); 1098 rfcomm_multiplexer_set_state_and_request_can_send_now_event(multiplexer, RFCOMM_MULTIPLEXER_SEND_UA_0_AND_DISC); 1099 return 1; 1100 1101 case BT_RFCOMM_DM: 1102 // DM #0 - we shouldn't get this, just give up 1103 log_info("Received DM #0"); 1104 log_info("-> Closing down multiplexer"); 1105 rfcomm_multiplexer_finalize(multiplexer); 1106 l2cap_disconnect(l2cap_cid, 0x13); 1107 return 1; 1108 1109 case BT_RFCOMM_UIH: 1110 if (packet[payload_offset] == BT_RFCOMM_CLD_CMD){ 1111 // Multiplexer close down (CLD) -> close mutliplexer 1112 log_info("Received Multiplexer close down command"); 1113 log_info("-> Closing down multiplexer"); 1114 rfcomm_multiplexer_finalize(multiplexer); 1115 l2cap_disconnect(l2cap_cid, 0x13); 1116 return 1; 1117 } 1118 switch (packet[payload_offset]){ 1119 case BT_RFCOMM_CLD_CMD: 1120 // Multiplexer close down (CLD) -> close mutliplexer 1121 log_info("Received Multiplexer close down command"); 1122 log_info("-> Closing down multiplexer"); 1123 rfcomm_multiplexer_finalize(multiplexer); 1124 l2cap_disconnect(l2cap_cid, 0x13); 1125 return 1; 1126 1127 case BT_RFCOMM_FCON_CMD: 1128 multiplexer->fcon = 0x81; 1129 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1130 return 1; 1131 1132 case BT_RFCOMM_FCOFF_CMD: 1133 multiplexer->fcon = 0x80; 1134 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1135 return 1; 1136 1137 case BT_RFCOMM_TEST_CMD: { 1138 log_info("Received test command"); 1139 int len = packet[payload_offset+1] >> 1; // length < 125 1140 if (len > RFCOMM_TEST_DATA_MAX_LEN){ 1141 len = RFCOMM_TEST_DATA_MAX_LEN; 1142 } 1143 len = btstack_min(len, size - 1 - payload_offset); // avoid information leak 1144 multiplexer->test_data_len = len; 1145 memcpy(multiplexer->test_data, &packet[payload_offset + 2], len); 1146 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1147 return 1; 1148 } 1149 default: 1150 break; 1151 } 1152 break; 1153 1154 default: 1155 break; 1156 1157 } 1158 return 0; 1159 } 1160 1161 static int rfcomm_multiplexer_ready_to_send(rfcomm_multiplexer_t * multiplexer){ 1162 if (multiplexer->send_dm_for_dlci) return 1; 1163 if (multiplexer->nsc_command) return 1; 1164 if (multiplexer->fcon & 0x80) return 1; 1165 switch (multiplexer->state){ 1166 case RFCOMM_MULTIPLEXER_SEND_SABM_0: 1167 case RFCOMM_MULTIPLEXER_SEND_UA_0: 1168 case RFCOMM_MULTIPLEXER_SEND_UA_0_AND_DISC: 1169 return 1; 1170 case RFCOMM_MULTIPLEXER_OPEN: 1171 if (multiplexer->test_data_len) { 1172 return 1; 1173 } 1174 break; 1175 default: 1176 break; 1177 } 1178 return 0; 1179 } 1180 1181 static void rfcomm_multiplexer_state_machine(rfcomm_multiplexer_t * multiplexer, RFCOMM_MULTIPLEXER_EVENT event){ 1182 1183 if (event != MULT_EV_READY_TO_SEND) return; 1184 1185 uint16_t l2cap_cid = multiplexer->l2cap_cid; 1186 1187 // process stored DM responses 1188 if (multiplexer->send_dm_for_dlci){ 1189 uint8_t dlci = multiplexer->send_dm_for_dlci; 1190 multiplexer->send_dm_for_dlci = 0; 1191 rfcomm_send_dm_pf(multiplexer, dlci); 1192 return; 1193 } 1194 1195 if (multiplexer->nsc_command){ 1196 uint8_t command = multiplexer->nsc_command; 1197 multiplexer->nsc_command = 0; 1198 rfcomm_send_uih_nsc_rsp(multiplexer, command); 1199 return; 1200 } 1201 1202 if (multiplexer->fcon & 0x80){ 1203 multiplexer->fcon &= 0x01; 1204 rfcomm_send_uih_fc_rsp(multiplexer, multiplexer->fcon); 1205 1206 if (multiplexer->fcon == 0) return; 1207 // trigger client to send again after sending FCon Response 1208 rfcomm_notify_channel_can_send(); 1209 return; 1210 } 1211 1212 switch (multiplexer->state) { 1213 case RFCOMM_MULTIPLEXER_SEND_SABM_0: 1214 log_info("Sending SABM #0 - (multi 0x%p)", multiplexer); 1215 multiplexer->state = RFCOMM_MULTIPLEXER_W4_UA_0; 1216 rfcomm_send_sabm(multiplexer, 0); 1217 break; 1218 case RFCOMM_MULTIPLEXER_SEND_UA_0: 1219 log_info("Sending UA #0"); 1220 multiplexer->state = RFCOMM_MULTIPLEXER_OPEN; 1221 rfcomm_send_ua(multiplexer, 0); 1222 1223 rfcomm_multiplexer_opened(multiplexer); 1224 break; 1225 case RFCOMM_MULTIPLEXER_SEND_UA_0_AND_DISC: 1226 log_info("Sending UA #0"); 1227 log_info("Closing down multiplexer"); 1228 multiplexer->state = RFCOMM_MULTIPLEXER_CLOSED; 1229 rfcomm_send_ua(multiplexer, 0); 1230 1231 rfcomm_multiplexer_finalize(multiplexer); 1232 l2cap_disconnect(l2cap_cid, 0x13); 1233 break; 1234 case RFCOMM_MULTIPLEXER_OPEN: 1235 // respond to test command 1236 if (multiplexer->test_data_len){ 1237 int len = multiplexer->test_data_len; 1238 log_info("Sending TEST Response with %u bytes", len); 1239 multiplexer->test_data_len = 0; 1240 rfcomm_send_uih_test_rsp(multiplexer, multiplexer->test_data, len); 1241 return; 1242 } 1243 break; 1244 default: 1245 break; 1246 } 1247 } 1248 1249 // MARK: RFCOMM CHANNEL 1250 1251 static void rfcomm_channel_send_credits(rfcomm_channel_t *channel, uint8_t credits){ 1252 channel->credits_incoming += credits; 1253 rfcomm_send_uih_credits(channel->multiplexer, channel->dlci, credits); 1254 } 1255 1256 static int rfcomm_channel_can_send(rfcomm_channel_t * channel){ 1257 if (!channel->credits_outgoing) return 0; 1258 if ((channel->multiplexer->fcon & 1) == 0) return 0; 1259 return l2cap_can_send_packet_now(channel->multiplexer->l2cap_cid); 1260 } 1261 1262 static void rfcomm_channel_opened(rfcomm_channel_t *rfChannel){ 1263 1264 log_info("rfcomm_channel_opened!"); 1265 1266 rfChannel->state = RFCOMM_CHANNEL_OPEN; 1267 rfcomm_emit_channel_opened(rfChannel, 0); 1268 rfcomm_emit_port_configuration(rfChannel); 1269 1270 // remove (potential) timer 1271 rfcomm_multiplexer_t *multiplexer = rfChannel->multiplexer; 1272 if (multiplexer->timer_active) { 1273 btstack_run_loop_remove_timer(&multiplexer->timer); 1274 multiplexer->timer_active = 0; 1275 } 1276 // hack for problem detecting authentication failure 1277 multiplexer->at_least_one_connection = 1; 1278 1279 // request can send now if channel ready 1280 if (rfcomm_channel_ready_to_send(rfChannel)){ 1281 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1282 } 1283 } 1284 1285 static void rfcomm_channel_packet_handler_uih(rfcomm_multiplexer_t *multiplexer, uint8_t * packet, uint16_t size){ 1286 const uint8_t frame_dlci = packet[0] >> 2; 1287 const uint8_t length_offset = (packet[2] & 1) ^ 1; // to be used for pos >= 3 1288 const uint8_t credit_offset = ((packet[1] & BT_RFCOMM_UIH_PF) == BT_RFCOMM_UIH_PF) ? 1 : 0; // credits for uih_pf frames 1289 const uint8_t payload_offset = 3 + length_offset + credit_offset; 1290 int request_can_send_now = 0; 1291 1292 rfcomm_channel_t * channel = rfcomm_channel_for_multiplexer_and_dlci(multiplexer, frame_dlci); 1293 if (!channel) return; 1294 1295 // handle new outgoing credits 1296 if (packet[1] == BT_RFCOMM_UIH_PF) { 1297 1298 // add them 1299 uint16_t new_credits = packet[3+length_offset]; 1300 channel->credits_outgoing += new_credits; 1301 log_info( "RFCOMM data UIH_PF, new credits channel 0x%02x: %u, now %u", channel->rfcomm_cid, new_credits, channel->credits_outgoing); 1302 1303 // notify channel statemachine 1304 rfcomm_channel_event_t channel_event = { CH_EVT_RCVD_CREDITS, 0 }; 1305 log_debug("rfcomm_channel_state_machine_with_channel, waiting_for_can_send_now %u", channel->waiting_for_can_send_now); 1306 rfcomm_channel_state_machine_with_channel(channel, &channel_event); 1307 if (rfcomm_channel_ready_to_send(channel) || channel->waiting_for_can_send_now){ 1308 request_can_send_now = 1; 1309 } 1310 } 1311 1312 // contains payload? 1313 if (size - 1 > payload_offset){ 1314 1315 // log_info( "RFCOMM data UIH_PF, size %u, channel %p", size-payload_offset-1, rfChannel->connection); 1316 1317 // decrease incoming credit counter 1318 if (channel->credits_incoming > 0){ 1319 channel->credits_incoming--; 1320 } 1321 1322 // deliver payload 1323 (channel->packet_handler)(RFCOMM_DATA_PACKET, channel->rfcomm_cid, 1324 &packet[payload_offset], size-payload_offset-1); 1325 } 1326 1327 // automatically provide new credits to remote device, if no incoming flow control 1328 if (!channel->incoming_flow_control && channel->credits_incoming < 5){ 1329 channel->new_credits_incoming = RFCOMM_CREDITS; 1330 request_can_send_now = 1; 1331 } 1332 1333 if (request_can_send_now){ 1334 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1335 } 1336 } 1337 1338 static void rfcomm_channel_accept_pn(rfcomm_channel_t *channel, rfcomm_channel_event_pn_t *event){ 1339 // priority of client request 1340 channel->pn_priority = event->priority; 1341 1342 // new credits 1343 channel->credits_outgoing = event->credits_outgoing; 1344 1345 // negotiate max frame size 1346 if (channel->max_frame_size > channel->multiplexer->max_frame_size) { 1347 channel->max_frame_size = channel->multiplexer->max_frame_size; 1348 } 1349 if (channel->max_frame_size > event->max_frame_size) { 1350 channel->max_frame_size = event->max_frame_size; 1351 } 1352 1353 } 1354 1355 static void rfcomm_channel_finalize(rfcomm_channel_t *channel){ 1356 1357 rfcomm_multiplexer_t *multiplexer = channel->multiplexer; 1358 1359 // remove from list 1360 btstack_linked_list_remove( &rfcomm_channels, (btstack_linked_item_t *) channel); 1361 1362 // free channel 1363 btstack_memory_rfcomm_channel_free(channel); 1364 1365 // update multiplexer timeout after channel was removed from list 1366 rfcomm_multiplexer_prepare_idle_timer(multiplexer); 1367 } 1368 1369 static void rfcomm_channel_state_machine_with_dlci(rfcomm_multiplexer_t * multiplexer, uint8_t dlci, const rfcomm_channel_event_t *event){ 1370 1371 // TODO: if client max frame size is smaller than RFCOMM_DEFAULT_SIZE, send PN 1372 1373 1374 // lookup existing channel 1375 rfcomm_channel_t * channel = rfcomm_channel_for_multiplexer_and_dlci(multiplexer, dlci); 1376 1377 // log_info("rfcomm_channel_state_machine_with_dlci lookup dlci #%u = 0x%08x - event %u", dlci, (int) channel, event->type); 1378 1379 if (channel) { 1380 rfcomm_channel_state_machine_with_channel(channel, event); 1381 if (rfcomm_channel_ready_to_send(channel)){ 1382 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1383 } 1384 return; 1385 } 1386 1387 // service registered? 1388 rfcomm_service_t * service = rfcomm_service_for_channel(dlci >> 1); 1389 // log_info("rfcomm_channel_state_machine_with_dlci service dlci #%u = 0x%08x", dlci, (int) service); 1390 if (!service) { 1391 // discard request by sending disconnected mode 1392 multiplexer->send_dm_for_dlci = dlci; 1393 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1394 return; 1395 } 1396 1397 // create channel for some events 1398 switch (event->type) { 1399 case CH_EVT_RCVD_SABM: 1400 case CH_EVT_RCVD_PN: 1401 case CH_EVT_RCVD_RPN_REQ: 1402 case CH_EVT_RCVD_RPN_CMD: 1403 // setup incoming channel 1404 channel = rfcomm_channel_create(multiplexer, service, dlci >> 1); 1405 if (!channel){ 1406 // discard request by sending disconnected mode 1407 multiplexer->send_dm_for_dlci = dlci; 1408 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1409 } 1410 break; 1411 default: 1412 break; 1413 } 1414 1415 if (!channel) { 1416 // discard request by sending disconnected mode 1417 multiplexer->send_dm_for_dlci = dlci; 1418 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1419 return; 1420 } 1421 1422 rfcomm_channel_state_machine_with_channel(channel, event); 1423 if (rfcomm_channel_ready_to_send(channel)){ 1424 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1425 } 1426 } 1427 1428 static void rfcomm_channel_packet_handler(rfcomm_multiplexer_t * multiplexer, uint8_t *packet, uint16_t size){ 1429 1430 UNUSED(size); // ok: fixed format messages 1431 1432 // rfcomm: (0) addr [76543 server channel] [2 direction: initiator uses 1] [1 C/R: CMD by initiator = 1] [0 EA=1] 1433 const uint8_t frame_dlci = packet[0] >> 2; 1434 uint8_t message_dlci; // used by commands in UIH(_PF) packets 1435 uint8_t message_len; // " 1436 1437 // rfcomm: (1) command/control 1438 // -- credits_offset = 1 if command == BT_RFCOMM_UIH_PF 1439 const uint8_t credit_offset = ((packet[1] & BT_RFCOMM_UIH_PF) == BT_RFCOMM_UIH_PF) ? 1 : 0; // credits for uih_pf frames 1440 // rfcomm: (2) length. if bit 0 is cleared, 2 byte length is used. (little endian) 1441 const uint8_t length_offset = (packet[2] & 1) ^ 1; // to be used for pos >= 3 1442 // rfcomm: (3+length_offset) credits if credits_offset == 1 1443 // rfcomm: (3+length_offest+credits_offset) 1444 const uint8_t payload_offset = 3 + length_offset + credit_offset; 1445 1446 rfcomm_channel_event_t event; 1447 rfcomm_channel_event_pn_t event_pn; 1448 rfcomm_channel_event_rpn_t event_rpn; 1449 rfcomm_channel_event_msc_t event_msc; 1450 1451 // switch by rfcomm message type 1452 switch(packet[1]) { 1453 1454 case BT_RFCOMM_SABM: 1455 event.type = CH_EVT_RCVD_SABM; 1456 log_info("Received SABM #%u", frame_dlci); 1457 rfcomm_channel_state_machine_with_dlci(multiplexer, frame_dlci, &event); 1458 break; 1459 1460 case BT_RFCOMM_UA: 1461 event.type = CH_EVT_RCVD_UA; 1462 log_info("Received UA #%u",frame_dlci); 1463 rfcomm_channel_state_machine_with_dlci(multiplexer, frame_dlci, &event); 1464 break; 1465 1466 case BT_RFCOMM_DISC: 1467 event.type = CH_EVT_RCVD_DISC; 1468 rfcomm_channel_state_machine_with_dlci(multiplexer, frame_dlci, &event); 1469 break; 1470 1471 case BT_RFCOMM_DM: 1472 case BT_RFCOMM_DM_PF: 1473 event.type = CH_EVT_RCVD_DM; 1474 rfcomm_channel_state_machine_with_dlci(multiplexer, frame_dlci, &event); 1475 break; 1476 1477 case BT_RFCOMM_UIH_PF: 1478 case BT_RFCOMM_UIH: 1479 1480 message_len = packet[payload_offset+1] >> 1; 1481 1482 switch (packet[payload_offset]) { 1483 case BT_RFCOMM_PN_CMD: 1484 message_dlci = packet[payload_offset+2]; 1485 event_pn.super.type = CH_EVT_RCVD_PN; 1486 event_pn.priority = packet[payload_offset+4]; 1487 event_pn.max_frame_size = little_endian_read_16(packet, payload_offset+6); 1488 event_pn.credits_outgoing = packet[payload_offset+9]; 1489 log_info("Received UIH Parameter Negotiation Command for #%u, credits %u", 1490 message_dlci, event_pn.credits_outgoing); 1491 rfcomm_channel_state_machine_with_dlci(multiplexer, message_dlci, (rfcomm_channel_event_t*) &event_pn); 1492 break; 1493 1494 case BT_RFCOMM_PN_RSP: 1495 message_dlci = packet[payload_offset+2]; 1496 event_pn.super.type = CH_EVT_RCVD_PN_RSP; 1497 event_pn.priority = packet[payload_offset+4]; 1498 event_pn.max_frame_size = little_endian_read_16(packet, payload_offset+6); 1499 event_pn.credits_outgoing = packet[payload_offset+9]; 1500 log_info("Received UIH Parameter Negotiation Response max frame %u, credits %u", 1501 event_pn.max_frame_size, event_pn.credits_outgoing); 1502 rfcomm_channel_state_machine_with_dlci(multiplexer, message_dlci, (rfcomm_channel_event_t*) &event_pn); 1503 break; 1504 1505 case BT_RFCOMM_MSC_CMD: 1506 message_dlci = packet[payload_offset+2] >> 2; 1507 event_msc.super.type = CH_EVT_RCVD_MSC_CMD; 1508 event_msc.modem_status = packet[payload_offset+3]; 1509 log_info("Received MSC CMD for #%u, ", message_dlci); 1510 rfcomm_channel_state_machine_with_dlci(multiplexer, message_dlci, (rfcomm_channel_event_t*) &event_msc); 1511 break; 1512 1513 case BT_RFCOMM_MSC_RSP: 1514 message_dlci = packet[payload_offset+2] >> 2; 1515 event.type = CH_EVT_RCVD_MSC_RSP; 1516 log_info("Received MSC RSP for #%u", message_dlci); 1517 rfcomm_channel_state_machine_with_dlci(multiplexer, message_dlci, &event); 1518 break; 1519 1520 case BT_RFCOMM_RPN_CMD: 1521 message_dlci = packet[payload_offset+2] >> 2; 1522 switch (message_len){ 1523 case 1: 1524 log_info("Received Remote Port Negotiation Request for #%u", message_dlci); 1525 event.type = CH_EVT_RCVD_RPN_REQ; 1526 rfcomm_channel_state_machine_with_dlci(multiplexer, message_dlci, &event); 1527 break; 1528 case 8: 1529 log_info("Received Remote Port Negotiation Update for #%u", message_dlci); 1530 event_rpn.super.type = CH_EVT_RCVD_RPN_CMD; 1531 event_rpn.data = *(rfcomm_rpn_data_t*) &packet[payload_offset+3]; 1532 rfcomm_channel_state_machine_with_dlci(multiplexer, message_dlci, (rfcomm_channel_event_t*) &event_rpn); 1533 break; 1534 default: 1535 break; 1536 } 1537 break; 1538 1539 case BT_RFCOMM_RPN_RSP: 1540 log_info("Received RPN response"); 1541 break; 1542 1543 case BT_RFCOMM_RLS_CMD: { 1544 log_info("Received RLS command"); 1545 message_dlci = packet[payload_offset+2] >> 2; 1546 rfcomm_channel_event_rls_t event_rls; 1547 event_rls.super.type = CH_EVT_RCVD_RLS_CMD; 1548 event_rls.line_status = packet[payload_offset+3]; 1549 rfcomm_channel_state_machine_with_dlci(multiplexer, message_dlci, (rfcomm_channel_event_t*) &event_rls); 1550 break; 1551 } 1552 1553 case BT_RFCOMM_RLS_RSP: 1554 log_info("Received RLS response"); 1555 break; 1556 1557 // Following commands are handled by rfcomm_multiplexer_l2cap_packet_handler 1558 // case BT_RFCOMM_TEST_CMD: 1559 // case BT_RFCOMM_FCOFF_CMD: 1560 // case BT_RFCOMM_FCON_CMD: 1561 // everything else is an not supported command 1562 default: { 1563 log_error("Received unknown UIH command packet - 0x%02x", packet[payload_offset]); 1564 multiplexer->nsc_command = packet[payload_offset]; 1565 break; 1566 } 1567 } 1568 break; 1569 1570 default: 1571 log_error("Received unknown RFCOMM message type %x", packet[1]); 1572 break; 1573 } 1574 1575 // trigger next action - example W4_PN_RSP: transition to SEND_SABM which only depends on "can send" 1576 if (rfcomm_multiplexer_ready_to_send(multiplexer)){ 1577 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1578 } 1579 } 1580 1581 static void rfcomm_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 1582 1583 if (packet_type == HCI_EVENT_PACKET){ 1584 rfcomm_hci_event_handler(packet, size); 1585 return; 1586 } 1587 1588 // we only handle l2cap packets for: 1589 if (packet_type != L2CAP_DATA_PACKET) return; 1590 1591 // - multiplexer itself 1592 int handled = rfcomm_multiplexer_l2cap_packet_handler(channel, packet, size); 1593 1594 if (handled) return; 1595 1596 // - channel over open mutliplexer 1597 rfcomm_multiplexer_t * multiplexer = rfcomm_multiplexer_for_l2cap_cid(channel); 1598 if (!multiplexer || multiplexer->state != RFCOMM_MULTIPLEXER_OPEN) return; 1599 1600 // channel data ? 1601 // rfcomm: (0) addr [76543 server channel] [2 direction: initiator uses 1] [1 C/R: CMD by initiator = 1] [0 EA=1] 1602 const uint8_t frame_dlci = packet[0] >> 2; 1603 1604 if (frame_dlci && (packet[1] == BT_RFCOMM_UIH || packet[1] == BT_RFCOMM_UIH_PF)) { 1605 rfcomm_channel_packet_handler_uih(multiplexer, packet, size); 1606 return; 1607 } 1608 1609 rfcomm_channel_packet_handler(multiplexer, packet, size); 1610 } 1611 1612 static int rfcomm_channel_ready_for_open(rfcomm_channel_t *channel){ 1613 // note: exchanging MSC isn't neccessary to consider channel open 1614 // note: having outgoing credits is also not necessary to consider channel open 1615 // log_info("rfcomm_channel_ready_for_open state %u, flags needed %04x, current %04x, rf credits %u, l2cap credits %u ", channel->state, RFCOMM_CHANNEL_STATE_VAR_RCVD_MSC_RSP|RFCOMM_CHANNEL_STATE_VAR_SENT_MSC_RSP|RFCOMM_CHANNEL_STATE_VAR_SENT_CREDITS, channel->state_var, channel->credits_outgoing, channel->multiplexer->l2cap_credits); 1616 // if ((channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SENT_MSC_RSP) == 0) return 0; 1617 // if (channel->credits_outgoing == 0) return 0; 1618 log_info("rfcomm_channel_ready_for_open state %u, flags needed %04x, current %04x, rf credits %u", 1619 channel->state, RFCOMM_CHANNEL_STATE_VAR_RCVD_MSC_RSP, channel->state_var, channel->credits_outgoing); 1620 if ((channel->state_var & RFCOMM_CHANNEL_STATE_VAR_RCVD_MSC_RSP) == 0) return 0; 1621 if ((channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SENT_CREDITS) == 0) return 0; 1622 1623 return 1; 1624 } 1625 1626 static int rfcomm_channel_ready_for_incoming_dlc_setup(rfcomm_channel_t * channel){ 1627 log_info("rfcomm_channel_ready_for_incoming_dlc_setup state var %04x", channel->state_var); 1628 // Client accept and SABM/UA is required, PN RSP is needed if PN was received 1629 if ((channel->state_var & RFCOMM_CHANNEL_STATE_VAR_CLIENT_ACCEPTED) == 0) return 0; 1630 if ((channel->state_var & RFCOMM_CHANNEL_STATE_VAR_RCVD_SABM ) == 0) return 0; 1631 if ((channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SEND_UA ) != 0) return 0; 1632 if ((channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SEND_PN_RSP ) != 0) return 0; 1633 return 1; 1634 } 1635 1636 inline static void rfcomm_channel_state_add(rfcomm_channel_t *channel, RFCOMM_CHANNEL_STATE_VAR event){ 1637 channel->state_var = (RFCOMM_CHANNEL_STATE_VAR) (channel->state_var | event); 1638 } 1639 inline static void rfcomm_channel_state_remove(rfcomm_channel_t *channel, RFCOMM_CHANNEL_STATE_VAR event){ 1640 channel->state_var = (RFCOMM_CHANNEL_STATE_VAR) (channel->state_var & ~event); 1641 } 1642 1643 static int rfcomm_channel_ready_to_send(rfcomm_channel_t * channel){ 1644 switch (channel->state){ 1645 case RFCOMM_CHANNEL_SEND_UIH_PN: 1646 log_debug("ch-ready: state %u", channel->state); 1647 return 1; 1648 case RFCOMM_CHANNEL_SEND_SABM_W4_UA: 1649 log_debug("ch-ready: state %u", channel->state); 1650 return 1; 1651 case RFCOMM_CHANNEL_SEND_UA_AFTER_DISC: 1652 log_debug("ch-ready: state %u", channel->state); 1653 return 1; 1654 case RFCOMM_CHANNEL_SEND_DISC: 1655 log_debug("ch-ready: state %u", channel->state); 1656 return 1; 1657 case RFCOMM_CHANNEL_SEND_DM: 1658 log_debug("ch-ready: state %u", channel->state); 1659 return 1; 1660 case RFCOMM_CHANNEL_OPEN: 1661 if (channel->new_credits_incoming) { 1662 log_debug("ch-ready: channel open & new_credits_incoming") ; 1663 return 1; 1664 } 1665 break; 1666 case RFCOMM_CHANNEL_DLC_SETUP: 1667 if (channel->state_var & ( 1668 RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_CMD | 1669 RFCOMM_CHANNEL_STATE_VAR_SEND_CREDITS 1670 )) { 1671 log_debug("ch-ready: channel dlc setup & send msc cmd or send credits") ; 1672 return 1; 1673 } 1674 break; 1675 1676 default: 1677 break; 1678 } 1679 1680 if (channel->state_var & ( 1681 RFCOMM_CHANNEL_STATE_VAR_SEND_PN_RSP | 1682 RFCOMM_CHANNEL_STATE_VAR_SEND_RPN_INFO | 1683 RFCOMM_CHANNEL_STATE_VAR_SEND_RPN_RSP | 1684 RFCOMM_CHANNEL_STATE_VAR_SEND_UA | 1685 RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_RSP 1686 )){ 1687 log_debug("ch-ready: state %x, state var %x", channel->state, channel->state_var); 1688 return 1; 1689 } 1690 1691 if (channel->rls_line_status != RFCOMM_RLS_STATUS_INVALID) { 1692 log_debug("ch-ready: rls_line_status"); 1693 return 1; 1694 } 1695 1696 return 0; 1697 } 1698 1699 1700 static void rfcomm_channel_state_machine_with_channel(rfcomm_channel_t *channel, const rfcomm_channel_event_t *event){ 1701 1702 // log_info("rfcomm_channel_state_machine_with_channel: state %u, state_var %04x, event %u", channel->state, channel->state_var ,event->type); 1703 1704 rfcomm_multiplexer_t *multiplexer = channel->multiplexer; 1705 1706 // TODO: integrate in common switch 1707 if (event->type == CH_EVT_RCVD_DISC){ 1708 rfcomm_emit_channel_closed(channel); 1709 channel->state = RFCOMM_CHANNEL_SEND_UA_AFTER_DISC; 1710 return; 1711 } 1712 1713 // TODO: integrate in common switch 1714 if (event->type == CH_EVT_RCVD_DM){ 1715 log_info("Received DM message for #%u", channel->dlci); 1716 log_info("-> Closing channel locally for #%u", channel->dlci); 1717 rfcomm_emit_channel_closed(channel); 1718 rfcomm_channel_finalize(channel); 1719 return; 1720 } 1721 1722 // remote port negotiation command - just accept everything for now 1723 // 1724 // "The RPN command can be used before a new DLC is opened and should be used whenever the port settings change." 1725 // "The RPN command is specified as optional in TS 07.10, but it is mandatory to recognize and respond to it in RFCOMM. 1726 // (Although the handling of individual settings are implementation-dependent.)" 1727 // 1728 1729 // TODO: integrate in common switch 1730 if (event->type == CH_EVT_RCVD_RPN_CMD){ 1731 // control port parameters 1732 rfcomm_channel_event_rpn_t *event_rpn = (rfcomm_channel_event_rpn_t*) event; 1733 rfcomm_rpn_data_update(&channel->rpn_data, &event_rpn->data); 1734 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_RPN_RSP); 1735 // notify client about new settings 1736 rfcomm_emit_port_configuration(channel); 1737 return; 1738 } 1739 1740 // TODO: integrate in common switch 1741 if (event->type == CH_EVT_RCVD_RPN_REQ){ 1742 // no values got accepted (no values have beens sent) 1743 channel->rpn_data.parameter_mask_0 = 0x00; 1744 channel->rpn_data.parameter_mask_1 = 0x00; 1745 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_RPN_RSP); 1746 return; 1747 } 1748 1749 if (event->type == CH_EVT_RCVD_RLS_CMD){ 1750 rfcomm_channel_event_rls_t * event_rls = (rfcomm_channel_event_rls_t*) event; 1751 channel->rls_line_status = event_rls->line_status & 0x0f; 1752 log_info("CH_EVT_RCVD_RLS_CMD setting line status to 0x%0x", channel->rls_line_status); 1753 rfcomm_emit_remote_line_status(channel, event_rls->line_status); 1754 return; 1755 } 1756 1757 // TODO: integrate in common switch 1758 if (event->type == CH_EVT_READY_TO_SEND){ 1759 if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SEND_RPN_RSP){ 1760 log_info("Sending Remote Port Negotiation RSP for #%u", channel->dlci); 1761 rfcomm_channel_state_remove(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_RPN_RSP); 1762 rfcomm_send_uih_rpn_rsp(multiplexer, channel->dlci, &channel->rpn_data); 1763 return; 1764 } 1765 if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_RSP){ 1766 log_info("Sending MSC RSP for #%u", channel->dlci); 1767 rfcomm_channel_state_remove(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_RSP); 1768 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SENT_MSC_RSP); 1769 rfcomm_send_uih_msc_rsp(multiplexer, channel->dlci, 0x8d); // ea=1,fc=0,rtc=1,rtr=1,ic=0,dv=1 1770 return; 1771 } 1772 if (channel->rls_line_status != RFCOMM_RLS_STATUS_INVALID){ 1773 log_info("Sending RLS RSP 0x%0x", channel->rls_line_status); 1774 uint8_t line_status = channel->rls_line_status; 1775 channel->rls_line_status = RFCOMM_RLS_STATUS_INVALID; 1776 rfcomm_send_uih_rls_rsp(multiplexer, channel->dlci, line_status); 1777 return; 1778 } 1779 } 1780 1781 // emit MSC status to app 1782 if (event->type == CH_EVT_RCVD_MSC_CMD){ 1783 // notify client about new settings 1784 rfcomm_channel_event_msc_t *event_msc = (rfcomm_channel_event_msc_t*) event; 1785 uint8_t modem_status_event[2+1]; 1786 modem_status_event[0] = RFCOMM_EVENT_REMOTE_MODEM_STATUS; 1787 modem_status_event[1] = 1; 1788 modem_status_event[2] = event_msc->modem_status; 1789 (channel->packet_handler)(HCI_EVENT_PACKET, channel->rfcomm_cid, (uint8_t*)&modem_status_event, sizeof(modem_status_event)); 1790 // no return, MSC_CMD will be handled by state machine below 1791 } 1792 1793 rfcomm_channel_event_pn_t * event_pn = (rfcomm_channel_event_pn_t*) event; 1794 1795 switch (channel->state) { 1796 case RFCOMM_CHANNEL_CLOSED: 1797 switch (event->type){ 1798 case CH_EVT_RCVD_SABM: 1799 log_info("-> Inform app"); 1800 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_RCVD_SABM); 1801 channel->state = RFCOMM_CHANNEL_INCOMING_SETUP; 1802 rfcomm_emit_connection_request(channel); 1803 break; 1804 case CH_EVT_RCVD_PN: 1805 rfcomm_channel_accept_pn(channel, event_pn); 1806 log_info("-> Inform app"); 1807 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_RCVD_PN); 1808 channel->state = RFCOMM_CHANNEL_INCOMING_SETUP; 1809 rfcomm_emit_connection_request(channel); 1810 break; 1811 default: 1812 break; 1813 } 1814 break; 1815 1816 case RFCOMM_CHANNEL_INCOMING_SETUP: 1817 switch (event->type){ 1818 case CH_EVT_RCVD_SABM: 1819 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_RCVD_SABM); 1820 if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_CLIENT_ACCEPTED) { 1821 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_UA); 1822 } 1823 break; 1824 case CH_EVT_RCVD_PN: 1825 rfcomm_channel_accept_pn(channel, event_pn); 1826 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_RCVD_PN); 1827 if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_CLIENT_ACCEPTED) { 1828 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_PN_RSP); 1829 } 1830 break; 1831 case CH_EVT_READY_TO_SEND: 1832 // if / else if is used to check for state transition after sending 1833 if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SEND_PN_RSP){ 1834 log_info("Sending UIH Parameter Negotiation Respond for #%u", channel->dlci); 1835 rfcomm_channel_state_remove(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_PN_RSP); 1836 rfcomm_send_uih_pn_response(multiplexer, channel->dlci, channel->pn_priority, channel->max_frame_size); 1837 } else if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SEND_UA){ 1838 log_info("Sending UA #%u", channel->dlci); 1839 rfcomm_channel_state_remove(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_UA); 1840 rfcomm_send_ua(multiplexer, channel->dlci); 1841 } 1842 if (rfcomm_channel_ready_for_incoming_dlc_setup(channel)){ 1843 log_info("Incomping setup done, requesting send MSC CMD and send Credits"); 1844 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_CMD); 1845 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_CREDITS); 1846 channel->state = RFCOMM_CHANNEL_DLC_SETUP; 1847 } 1848 break; 1849 default: 1850 break; 1851 } 1852 break; 1853 1854 case RFCOMM_CHANNEL_W4_MULTIPLEXER: 1855 switch (event->type) { 1856 case CH_EVT_MULTIPLEXER_READY: 1857 log_info("Muliplexer opened, sending UIH PN next"); 1858 channel->state = RFCOMM_CHANNEL_SEND_UIH_PN; 1859 break; 1860 default: 1861 break; 1862 } 1863 break; 1864 1865 case RFCOMM_CHANNEL_SEND_UIH_PN: 1866 switch (event->type) { 1867 case CH_EVT_READY_TO_SEND: 1868 log_info("Sending UIH Parameter Negotiation Command for #%u (channel 0x%p)", channel->dlci, channel ); 1869 channel->state = RFCOMM_CHANNEL_W4_PN_RSP; 1870 rfcomm_send_uih_pn_command(multiplexer, channel->dlci, channel->max_frame_size); 1871 break; 1872 default: 1873 break; 1874 } 1875 break; 1876 1877 case RFCOMM_CHANNEL_W4_PN_RSP: 1878 switch (event->type){ 1879 case CH_EVT_RCVD_PN_RSP: 1880 // update max frame size 1881 if (channel->max_frame_size > event_pn->max_frame_size) { 1882 channel->max_frame_size = event_pn->max_frame_size; 1883 } 1884 // new credits 1885 channel->credits_outgoing = event_pn->credits_outgoing; 1886 channel->state = RFCOMM_CHANNEL_SEND_SABM_W4_UA; 1887 break; 1888 default: 1889 break; 1890 } 1891 break; 1892 1893 case RFCOMM_CHANNEL_SEND_SABM_W4_UA: 1894 switch (event->type) { 1895 case CH_EVT_READY_TO_SEND: 1896 log_info("Sending SABM #%u", channel->dlci); 1897 channel->state = RFCOMM_CHANNEL_W4_UA; 1898 rfcomm_send_sabm(multiplexer, channel->dlci); 1899 break; 1900 default: 1901 break; 1902 } 1903 break; 1904 1905 case RFCOMM_CHANNEL_W4_UA: 1906 switch (event->type){ 1907 case CH_EVT_RCVD_UA: 1908 channel->state = RFCOMM_CHANNEL_DLC_SETUP; 1909 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_CMD); 1910 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_CREDITS); 1911 break; 1912 default: 1913 break; 1914 } 1915 break; 1916 1917 case RFCOMM_CHANNEL_DLC_SETUP: 1918 switch (event->type){ 1919 case CH_EVT_RCVD_MSC_CMD: 1920 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_RCVD_MSC_CMD); 1921 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_RSP); 1922 break; 1923 case CH_EVT_RCVD_MSC_RSP: 1924 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_RCVD_MSC_RSP); 1925 break; 1926 1927 case CH_EVT_READY_TO_SEND: 1928 if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_CMD){ 1929 log_info("Sending MSC CMD for #%u", channel->dlci); 1930 rfcomm_channel_state_remove(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_CMD); 1931 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SENT_MSC_CMD); 1932 rfcomm_send_uih_msc_cmd(multiplexer, channel->dlci , 0x8d); // ea=1,fc=0,rtc=1,rtr=1,ic=0,dv=1 1933 break; 1934 } 1935 if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SEND_CREDITS){ 1936 log_info("Providing credits for #%u", channel->dlci); 1937 rfcomm_channel_state_remove(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_CREDITS); 1938 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SENT_CREDITS); 1939 1940 if (channel->new_credits_incoming) { 1941 uint8_t new_credits = channel->new_credits_incoming; 1942 channel->new_credits_incoming = 0; 1943 rfcomm_channel_send_credits(channel, new_credits); 1944 } 1945 break; 1946 1947 } 1948 break; 1949 default: 1950 break; 1951 } 1952 // finally done? 1953 if (rfcomm_channel_ready_for_open(channel)){ 1954 channel->state = RFCOMM_CHANNEL_OPEN; 1955 rfcomm_channel_opened(channel); 1956 } 1957 break; 1958 1959 case RFCOMM_CHANNEL_OPEN: 1960 switch (event->type){ 1961 case CH_EVT_RCVD_MSC_CMD: 1962 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_RSP); 1963 break; 1964 case CH_EVT_READY_TO_SEND: 1965 if (channel->new_credits_incoming) { 1966 uint8_t new_credits = channel->new_credits_incoming; 1967 channel->new_credits_incoming = 0; 1968 rfcomm_channel_send_credits(channel, new_credits); 1969 break; 1970 } 1971 break; 1972 case CH_EVT_RCVD_CREDITS: 1973 rfcomm_notify_channel_can_send(); 1974 break; 1975 default: 1976 break; 1977 } 1978 break; 1979 1980 case RFCOMM_CHANNEL_SEND_DM: 1981 switch (event->type) { 1982 case CH_EVT_READY_TO_SEND: 1983 log_info("Sending DM_PF for #%u", channel->dlci); 1984 // don't emit channel closed - channel was never open 1985 channel->state = RFCOMM_CHANNEL_CLOSED; 1986 rfcomm_send_dm_pf(multiplexer, channel->dlci); 1987 rfcomm_channel_finalize(channel); 1988 break; 1989 default: 1990 break; 1991 } 1992 break; 1993 1994 case RFCOMM_CHANNEL_SEND_DISC: 1995 switch (event->type) { 1996 case CH_EVT_READY_TO_SEND: 1997 channel->state = RFCOMM_CHANNEL_W4_UA_AFTER_DISC; 1998 rfcomm_send_disc(multiplexer, channel->dlci); 1999 break; 2000 default: 2001 break; 2002 } 2003 break; 2004 2005 case RFCOMM_CHANNEL_W4_UA_AFTER_DISC: 2006 switch (event->type){ 2007 case CH_EVT_RCVD_UA: 2008 channel->state = RFCOMM_CHANNEL_CLOSED; 2009 rfcomm_emit_channel_closed(channel); 2010 rfcomm_channel_finalize(channel); 2011 break; 2012 default: 2013 break; 2014 } 2015 break; 2016 2017 case RFCOMM_CHANNEL_SEND_UA_AFTER_DISC: 2018 switch (event->type) { 2019 case CH_EVT_READY_TO_SEND: 2020 log_info("Sending UA after DISC for #%u", channel->dlci); 2021 channel->state = RFCOMM_CHANNEL_CLOSED; 2022 rfcomm_send_ua(multiplexer, channel->dlci); 2023 rfcomm_channel_finalize(channel); 2024 break; 2025 default: 2026 break; 2027 } 2028 break; 2029 2030 default: 2031 break; 2032 } 2033 } 2034 2035 // MARK: RFCOMM BTstack API 2036 2037 void rfcomm_init(void){ 2038 rfcomm_client_cid_generator = 0; 2039 rfcomm_multiplexers = NULL; 2040 rfcomm_services = NULL; 2041 rfcomm_channels = NULL; 2042 rfcomm_security_level = LEVEL_2; 2043 } 2044 2045 void rfcomm_set_required_security_level(gap_security_level_t security_level){ 2046 rfcomm_security_level = security_level; 2047 } 2048 2049 int rfcomm_can_send_packet_now(uint16_t rfcomm_cid){ 2050 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2051 if (!channel){ 2052 log_error("rfcomm_send cid 0x%02x doesn't exist!", rfcomm_cid); 2053 return 0; 2054 } 2055 return rfcomm_channel_can_send(channel); 2056 } 2057 2058 void rfcomm_request_can_send_now_event(uint16_t rfcomm_cid){ 2059 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2060 if (!channel){ 2061 log_error("rfcomm_send cid 0x%02x doesn't exist!", rfcomm_cid); 2062 return; 2063 } 2064 channel->waiting_for_can_send_now = 1; 2065 l2cap_request_can_send_now_event(channel->multiplexer->l2cap_cid); 2066 } 2067 2068 static int rfcomm_assert_send_valid(rfcomm_channel_t * channel , uint16_t len){ 2069 if (len > channel->max_frame_size){ 2070 log_error("rfcomm_send cid 0x%02x, rfcomm data lenght exceeds MTU!", channel->rfcomm_cid); 2071 return RFCOMM_DATA_LEN_EXCEEDS_MTU; 2072 } 2073 2074 if (!channel->credits_outgoing){ 2075 log_info("rfcomm_send cid 0x%02x, no rfcomm outgoing credits!", channel->rfcomm_cid); 2076 return RFCOMM_NO_OUTGOING_CREDITS; 2077 } 2078 2079 if ((channel->multiplexer->fcon & 1) == 0){ 2080 log_info("rfcomm_send cid 0x%02x, aggregate flow off!", channel->rfcomm_cid); 2081 return RFCOMM_AGGREGATE_FLOW_OFF; 2082 } 2083 return 0; 2084 } 2085 2086 // pre: rfcomm_can_send_packet_now(rfcomm_cid) == true 2087 int rfcomm_reserve_packet_buffer(void){ 2088 return l2cap_reserve_packet_buffer(); 2089 } 2090 2091 void rfcomm_release_packet_buffer(void){ 2092 l2cap_release_packet_buffer(); 2093 } 2094 2095 uint8_t * rfcomm_get_outgoing_buffer(void){ 2096 uint8_t * rfcomm_out_buffer = l2cap_get_outgoing_buffer(); 2097 // address + control + length (16) + no credit field 2098 return &rfcomm_out_buffer[4]; 2099 } 2100 2101 uint16_t rfcomm_get_max_frame_size(uint16_t rfcomm_cid){ 2102 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2103 if (!channel){ 2104 log_error("rfcomm_get_max_frame_size cid 0x%02x doesn't exist!", rfcomm_cid); 2105 return 0; 2106 } 2107 return channel->max_frame_size; 2108 } 2109 2110 int rfcomm_send_prepared(uint16_t rfcomm_cid, uint16_t len){ 2111 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2112 if (!channel){ 2113 log_error("rfcomm_send_prepared cid 0x%02x doesn't exist!", rfcomm_cid); 2114 return 0; 2115 } 2116 2117 int err = rfcomm_assert_send_valid(channel, len); 2118 if (err) return err; 2119 if (!l2cap_can_send_prepared_packet_now(channel->multiplexer->l2cap_cid)){ 2120 log_error("rfcomm_send_prepared: l2cap cannot send now"); 2121 return BTSTACK_ACL_BUFFERS_FULL; 2122 } 2123 2124 // send might cause l2cap to emit new credits, update counters first 2125 if (len){ 2126 channel->credits_outgoing--; 2127 } else { 2128 log_info("sending empty RFCOMM packet for cid %02x", rfcomm_cid); 2129 } 2130 2131 int result = rfcomm_send_uih_prepared(channel->multiplexer, channel->dlci, len); 2132 2133 if (result != 0) { 2134 if (len) { 2135 channel->credits_outgoing++; 2136 } 2137 log_error("rfcomm_send_prepared: error %d", result); 2138 return result; 2139 } 2140 2141 return result; 2142 } 2143 2144 int rfcomm_send(uint16_t rfcomm_cid, uint8_t *data, uint16_t len){ 2145 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2146 if (!channel){ 2147 log_error("cid 0x%02x doesn't exist!", rfcomm_cid); 2148 return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 2149 } 2150 2151 int err = rfcomm_assert_send_valid(channel, len); 2152 if (err) return err; 2153 if (!l2cap_can_send_packet_now(channel->multiplexer->l2cap_cid)){ 2154 log_error("rfcomm_send_internal: l2cap cannot send now"); 2155 return BTSTACK_ACL_BUFFERS_FULL; 2156 } 2157 2158 rfcomm_reserve_packet_buffer(); 2159 uint8_t * rfcomm_payload = rfcomm_get_outgoing_buffer(); 2160 memcpy(rfcomm_payload, data, len); 2161 err = rfcomm_send_prepared(rfcomm_cid, len); 2162 if (err){ 2163 rfcomm_release_packet_buffer(); 2164 } 2165 return err; 2166 } 2167 2168 // Sends Local Lnie Status, see LINE_STATUS_.. 2169 int rfcomm_send_local_line_status(uint16_t rfcomm_cid, uint8_t line_status){ 2170 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2171 if (!channel){ 2172 log_error("rfcomm_send_local_line_status cid 0x%02x doesn't exist!", rfcomm_cid); 2173 return 0; 2174 } 2175 return rfcomm_send_uih_rls_cmd(channel->multiplexer, channel->dlci, line_status); 2176 } 2177 2178 // Sned local modem status. see MODEM_STAUS_.. 2179 int rfcomm_send_modem_status(uint16_t rfcomm_cid, uint8_t modem_status){ 2180 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2181 if (!channel){ 2182 log_error("rfcomm_send_modem_status cid 0x%02x doesn't exist!", rfcomm_cid); 2183 return 0; 2184 } 2185 return rfcomm_send_uih_msc_cmd(channel->multiplexer, channel->dlci, modem_status); 2186 } 2187 2188 // Configure remote port 2189 int rfcomm_send_port_configuration(uint16_t rfcomm_cid, rpn_baud_t baud_rate, rpn_data_bits_t data_bits, rpn_stop_bits_t stop_bits, rpn_parity_t parity, rpn_flow_control_t flow_control){ 2190 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2191 if (!channel){ 2192 log_error("rfcomm_send_port_configuration cid 0x%02x doesn't exist!", rfcomm_cid); 2193 return 0; 2194 } 2195 rfcomm_rpn_data_t rpn_data; 2196 rpn_data.baud_rate = baud_rate; 2197 rpn_data.flags = data_bits | (stop_bits << 2) | (parity << 3); 2198 rpn_data.flow_control = flow_control; 2199 rpn_data.xon = 0; 2200 rpn_data.xoff = 0; 2201 rpn_data.parameter_mask_0 = 0x1f; // all but xon/xoff 2202 rpn_data.parameter_mask_1 = 0x3f; // all flow control options 2203 return rfcomm_send_uih_rpn_cmd(channel->multiplexer, channel->dlci, &rpn_data); 2204 } 2205 2206 // Query remote port 2207 int rfcomm_query_port_configuration(uint16_t rfcomm_cid){ 2208 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2209 if (!channel){ 2210 log_error("rfcomm_query_port_configuration cid 0x%02x doesn't exist!", rfcomm_cid); 2211 return 0; 2212 } 2213 return rfcomm_send_uih_rpn_req(channel->multiplexer, channel->dlci); 2214 } 2215 2216 2217 static uint8_t rfcomm_channel_create_internal(btstack_packet_handler_t packet_handler, bd_addr_t addr, uint8_t server_channel, uint8_t incoming_flow_control, uint8_t initial_credits, uint16_t * out_rfcomm_cid){ 2218 log_info("RFCOMM_CREATE_CHANNEL addr %s channel #%u init credits %u", bd_addr_to_str(addr), server_channel, initial_credits); 2219 2220 // create new multiplexer if necessary 2221 uint8_t status = 0; 2222 uint8_t dlci = 0; 2223 int new_multiplexer = 0; 2224 rfcomm_channel_t * channel = NULL; 2225 rfcomm_multiplexer_t * multiplexer = rfcomm_multiplexer_for_addr(addr); 2226 if (!multiplexer) { 2227 multiplexer = rfcomm_multiplexer_create_for_addr(addr); 2228 if (!multiplexer){ 2229 status = BTSTACK_MEMORY_ALLOC_FAILED; 2230 goto fail; 2231 } 2232 multiplexer->outgoing = 1; 2233 multiplexer->state = RFCOMM_MULTIPLEXER_W4_CONNECT; 2234 new_multiplexer = 1; 2235 } 2236 2237 // check if channel for this remote service already exists 2238 dlci = (server_channel << 1) | (multiplexer->outgoing ^ 1); 2239 channel = rfcomm_channel_for_multiplexer_and_dlci(multiplexer, dlci); 2240 if (channel){ 2241 status = RFCOMM_CHANNEL_ALREADY_REGISTERED; 2242 goto fail; 2243 } 2244 2245 // prepare channel 2246 channel = rfcomm_channel_create(multiplexer, NULL, server_channel); 2247 if (!channel){ 2248 status = BTSTACK_MEMORY_ALLOC_FAILED; 2249 goto fail; 2250 } 2251 2252 // rfcomm_cid is already assigned by rfcomm_channel_create 2253 channel->incoming_flow_control = incoming_flow_control; 2254 channel->new_credits_incoming = initial_credits; 2255 channel->packet_handler = packet_handler; 2256 2257 // return rfcomm_cid 2258 if (out_rfcomm_cid){ 2259 *out_rfcomm_cid = channel->rfcomm_cid; 2260 } 2261 2262 // start multiplexer setup 2263 if (multiplexer->state != RFCOMM_MULTIPLEXER_OPEN) { 2264 channel->state = RFCOMM_CHANNEL_W4_MULTIPLEXER; 2265 uint16_t l2cap_cid = 0; 2266 status = l2cap_create_channel(rfcomm_packet_handler, addr, BLUETOOTH_PROTOCOL_RFCOMM, l2cap_max_mtu(), &l2cap_cid); 2267 if (status) goto fail; 2268 multiplexer->l2cap_cid = l2cap_cid; 2269 return 0; 2270 } 2271 2272 channel->state = RFCOMM_CHANNEL_SEND_UIH_PN; 2273 2274 // start connecting, if multiplexer is already up and running 2275 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 2276 return 0; 2277 2278 fail: 2279 if (new_multiplexer) btstack_memory_rfcomm_multiplexer_free(multiplexer); 2280 if (channel) btstack_memory_rfcomm_channel_free(channel); 2281 return status; 2282 } 2283 2284 uint8_t rfcomm_create_channel_with_initial_credits(btstack_packet_handler_t packet_handler, bd_addr_t addr, uint8_t server_channel, uint8_t initial_credits, uint16_t * out_rfcomm_cid){ 2285 return rfcomm_channel_create_internal(packet_handler, addr, server_channel, 1, initial_credits, out_rfcomm_cid); 2286 } 2287 2288 uint8_t rfcomm_create_channel(btstack_packet_handler_t packet_handler, bd_addr_t addr, uint8_t server_channel, uint16_t * out_rfcomm_cid){ 2289 return rfcomm_channel_create_internal(packet_handler, addr, server_channel, 0, RFCOMM_CREDITS, out_rfcomm_cid); 2290 } 2291 2292 void rfcomm_disconnect(uint16_t rfcomm_cid){ 2293 log_info("RFCOMM_DISCONNECT cid 0x%02x", rfcomm_cid); 2294 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2295 if (!channel) return; 2296 2297 channel->state = RFCOMM_CHANNEL_SEND_DISC; 2298 l2cap_request_can_send_now_event(channel->multiplexer->l2cap_cid); 2299 } 2300 2301 static uint8_t rfcomm_register_service_internal(btstack_packet_handler_t packet_handler, 2302 uint8_t channel, uint16_t max_frame_size, uint8_t incoming_flow_control, uint8_t initial_credits){ 2303 2304 log_info("RFCOMM_REGISTER_SERVICE channel #%u mtu %u flow_control %u credits %u", 2305 channel, max_frame_size, incoming_flow_control, initial_credits); 2306 2307 // check if already registered 2308 rfcomm_service_t * service = rfcomm_service_for_channel(channel); 2309 if (service){ 2310 return RFCOMM_CHANNEL_ALREADY_REGISTERED; 2311 } 2312 2313 // alloc structure 2314 service = btstack_memory_rfcomm_service_get(); 2315 if (!service) { 2316 return BTSTACK_MEMORY_ALLOC_FAILED; 2317 } 2318 2319 // register with l2cap if not registered before, max MTU 2320 if (btstack_linked_list_empty(&rfcomm_services)){ 2321 l2cap_register_service(rfcomm_packet_handler, BLUETOOTH_PROTOCOL_RFCOMM, 0xffff, rfcomm_security_level); 2322 } 2323 2324 // fill in 2325 service->packet_handler = packet_handler; 2326 service->server_channel = channel; 2327 service->max_frame_size = max_frame_size; 2328 service->incoming_flow_control = incoming_flow_control; 2329 service->incoming_initial_credits = initial_credits; 2330 2331 // add to services list 2332 btstack_linked_list_add(&rfcomm_services, (btstack_linked_item_t *) service); 2333 2334 return 0; 2335 } 2336 2337 uint8_t rfcomm_register_service_with_initial_credits(btstack_packet_handler_t packet_handler, 2338 uint8_t channel, uint16_t max_frame_size, uint8_t initial_credits){ 2339 2340 return rfcomm_register_service_internal(packet_handler, channel, max_frame_size, 1, initial_credits); 2341 } 2342 2343 uint8_t rfcomm_register_service(btstack_packet_handler_t packet_handler, uint8_t channel, 2344 uint16_t max_frame_size){ 2345 2346 return rfcomm_register_service_internal(packet_handler, channel, max_frame_size, 0,RFCOMM_CREDITS); 2347 } 2348 2349 void rfcomm_unregister_service(uint8_t service_channel){ 2350 log_info("RFCOMM_UNREGISTER_SERVICE #%u", service_channel); 2351 rfcomm_service_t *service = rfcomm_service_for_channel(service_channel); 2352 if (!service) return; 2353 btstack_linked_list_remove(&rfcomm_services, (btstack_linked_item_t *) service); 2354 btstack_memory_rfcomm_service_free(service); 2355 2356 // unregister if no services active 2357 if (btstack_linked_list_empty(&rfcomm_services)){ 2358 // bt_send_cmd(&l2cap_unregister_service, BLUETOOTH_PROTOCOL_RFCOMM); 2359 l2cap_unregister_service(BLUETOOTH_PROTOCOL_RFCOMM); 2360 } 2361 } 2362 2363 void rfcomm_accept_connection(uint16_t rfcomm_cid){ 2364 log_info("RFCOMM_ACCEPT_CONNECTION cid 0x%02x", rfcomm_cid); 2365 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2366 if (!channel) return; 2367 switch (channel->state) { 2368 case RFCOMM_CHANNEL_INCOMING_SETUP: 2369 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_CLIENT_ACCEPTED); 2370 if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_RCVD_PN){ 2371 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_PN_RSP); 2372 l2cap_request_can_send_now_event(channel->multiplexer->l2cap_cid); 2373 } 2374 if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_RCVD_SABM){ 2375 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_UA); 2376 l2cap_request_can_send_now_event(channel->multiplexer->l2cap_cid); 2377 } 2378 // at least one of { PN RSP, UA } needs to be sent 2379 // state transistion incoming setup -> dlc setup happens in rfcomm_run after these have been sent 2380 break; 2381 default: 2382 break; 2383 } 2384 2385 } 2386 2387 void rfcomm_decline_connection(uint16_t rfcomm_cid){ 2388 log_info("RFCOMM_DECLINE_CONNECTION cid 0x%02x", rfcomm_cid); 2389 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2390 if (!channel) return; 2391 switch (channel->state) { 2392 case RFCOMM_CHANNEL_INCOMING_SETUP: 2393 channel->state = RFCOMM_CHANNEL_SEND_DM; 2394 l2cap_request_can_send_now_event(channel->multiplexer->l2cap_cid); 2395 break; 2396 default: 2397 break; 2398 } 2399 } 2400 2401 void rfcomm_grant_credits(uint16_t rfcomm_cid, uint8_t credits){ 2402 log_info("RFCOMM_GRANT_CREDITS cid 0x%02x credits %u", rfcomm_cid, credits); 2403 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2404 if (!channel) return; 2405 if (!channel->incoming_flow_control) return; 2406 channel->new_credits_incoming += credits; 2407 2408 // process 2409 l2cap_request_can_send_now_event(channel->multiplexer->l2cap_cid); 2410 } 2411 2412 2413