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 rfcomm_emit_channel_closed(channel); 781 break; 782 case RFCOMM_CHANNEL_SEND_UA_AFTER_DISC: 783 // remote didn't wait until we send the UA disc 784 break; 785 default: 786 rfcomm_emit_channel_opened(channel, RFCOMM_MULTIPLEXER_STOPPED); 787 break; 788 } 789 // remove from list 790 it->next = it->next->next; 791 // free channel struct 792 btstack_memory_rfcomm_channel_free(channel); 793 } else { 794 it = it->next; 795 } 796 } 797 798 // remove mutliplexer 799 rfcomm_multiplexer_free(multiplexer); 800 } 801 802 static void rfcomm_multiplexer_timer_handler(btstack_timer_source_t *timer){ 803 rfcomm_multiplexer_t * multiplexer = (rfcomm_multiplexer_t*) btstack_run_loop_get_timer_context(timer); 804 if (rfcomm_multiplexer_has_channels(multiplexer)) return; 805 806 log_info("rfcomm_multiplexer_timer_handler timeout: shutting down multiplexer! (no channels)"); 807 uint16_t l2cap_cid = multiplexer->l2cap_cid; 808 rfcomm_multiplexer_finalize(multiplexer); 809 l2cap_disconnect(l2cap_cid, 0x13); 810 } 811 812 static void rfcomm_multiplexer_prepare_idle_timer(rfcomm_multiplexer_t * multiplexer){ 813 if (multiplexer->timer_active) { 814 btstack_run_loop_remove_timer(&multiplexer->timer); 815 multiplexer->timer_active = 0; 816 } 817 if (rfcomm_multiplexer_has_channels(multiplexer)) return; 818 819 // start idle timer for multiplexer timeout check as there are no rfcomm channels yet 820 btstack_run_loop_set_timer(&multiplexer->timer, RFCOMM_MULIPLEXER_TIMEOUT_MS); 821 btstack_run_loop_set_timer_handler(&multiplexer->timer, rfcomm_multiplexer_timer_handler); 822 btstack_run_loop_set_timer_context(&multiplexer->timer, multiplexer); 823 btstack_run_loop_add_timer(&multiplexer->timer); 824 multiplexer->timer_active = 1; 825 } 826 827 static void rfcomm_multiplexer_opened(rfcomm_multiplexer_t *multiplexer){ 828 log_info("Multiplexer up and running"); 829 multiplexer->state = RFCOMM_MULTIPLEXER_OPEN; 830 831 const rfcomm_channel_event_t event = { CH_EVT_MULTIPLEXER_READY, 0}; 832 833 // transition of channels that wait for multiplexer 834 btstack_linked_item_t *it; 835 for (it = (btstack_linked_item_t *) rfcomm_channels; it ; it = it->next){ 836 rfcomm_channel_t * channel = ((rfcomm_channel_t *) it); 837 if (channel->multiplexer != multiplexer) continue; 838 rfcomm_channel_state_machine_with_channel(channel, &event); 839 if (rfcomm_channel_ready_to_send(channel)){ 840 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 841 } 842 } 843 rfcomm_multiplexer_prepare_idle_timer(multiplexer); 844 845 // request can send now for multiplexer if ready 846 if (rfcomm_multiplexer_ready_to_send(multiplexer)){ 847 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 848 } 849 } 850 851 static void rfcomm_handle_can_send_now(uint16_t l2cap_cid){ 852 853 log_debug("rfcomm_handle_can_send_now enter: %u", l2cap_cid); 854 855 btstack_linked_list_iterator_t it; 856 int token_consumed = 0; 857 858 // forward token to multiplexer 859 btstack_linked_list_iterator_init(&it, &rfcomm_multiplexers); 860 while (!token_consumed && btstack_linked_list_iterator_has_next(&it)){ 861 rfcomm_multiplexer_t * multiplexer = (rfcomm_multiplexer_t *) btstack_linked_list_iterator_next(&it); 862 if (multiplexer->l2cap_cid != l2cap_cid) continue; 863 if (rfcomm_multiplexer_ready_to_send(multiplexer)){ 864 log_debug("rfcomm_handle_can_send_now enter: multiplexer token"); 865 token_consumed = 1; 866 rfcomm_multiplexer_state_machine(multiplexer, MULT_EV_READY_TO_SEND); 867 } 868 } 869 870 // forward token to channel state machine 871 btstack_linked_list_iterator_init(&it, &rfcomm_channels); 872 while (!token_consumed && btstack_linked_list_iterator_has_next(&it)){ 873 rfcomm_channel_t * channel = (rfcomm_channel_t *) btstack_linked_list_iterator_next(&it); 874 if (channel->multiplexer->l2cap_cid != l2cap_cid) continue; 875 // channel state machine 876 if (rfcomm_channel_ready_to_send(channel)){ 877 log_debug("rfcomm_handle_can_send_now enter: channel token"); 878 token_consumed = 1; 879 const rfcomm_channel_event_t event = { CH_EVT_READY_TO_SEND, 0 }; 880 rfcomm_channel_state_machine_with_channel(channel, &event); 881 } 882 } 883 884 // forward token to client 885 btstack_linked_list_iterator_init(&it, &rfcomm_channels); 886 while (!token_consumed && btstack_linked_list_iterator_has_next(&it)){ 887 rfcomm_channel_t * channel = (rfcomm_channel_t *) btstack_linked_list_iterator_next(&it); 888 if (channel->multiplexer->l2cap_cid != l2cap_cid) continue; 889 // client waiting for can send now 890 if (!channel->waiting_for_can_send_now) continue; 891 if (!channel->credits_outgoing) continue; 892 if ((channel->multiplexer->fcon & 1) == 0) continue; 893 894 log_debug("rfcomm_handle_can_send_now enter: client token"); 895 token_consumed = 1; 896 channel->waiting_for_can_send_now = 0; 897 rfcomm_emit_can_send_now(channel); 898 } 899 900 // if token was consumed, request another one 901 if (token_consumed) { 902 l2cap_request_can_send_now_event(l2cap_cid); 903 } 904 905 log_debug("rfcomm_handle_can_send_now exit"); 906 } 907 908 static void rfcomm_multiplexer_set_state_and_request_can_send_now_event(rfcomm_multiplexer_t * multiplexer, RFCOMM_MULTIPLEXER_STATE state){ 909 multiplexer->state = state; 910 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 911 } 912 913 /** 914 * @return handled packet 915 */ 916 static int rfcomm_hci_event_handler(uint8_t *packet, uint16_t size){ 917 918 UNUSED(size); // ok: handling own l2cap events 919 920 bd_addr_t event_addr; 921 uint16_t psm; 922 uint16_t l2cap_cid; 923 hci_con_handle_t con_handle; 924 rfcomm_multiplexer_t *multiplexer = NULL; 925 uint8_t status; 926 927 switch (hci_event_packet_get_type(packet)) { 928 929 // accept incoming rfcomm connection if no multiplexer exists yet 930 case L2CAP_EVENT_INCOMING_CONNECTION: 931 // data: event(8), len(8), address(48), handle (16), psm (16), source cid(16) dest cid(16) 932 reverse_bd_addr(&packet[2], event_addr); 933 con_handle = little_endian_read_16(packet, 8); 934 psm = little_endian_read_16(packet, 10); 935 l2cap_cid = little_endian_read_16(packet, 12); 936 937 if (psm != BLUETOOTH_PROTOCOL_RFCOMM) break; 938 939 multiplexer = rfcomm_multiplexer_for_addr(event_addr); 940 941 if (multiplexer) { 942 log_info("INCOMING_CONNECTION (l2cap_cid 0x%02x) for BLUETOOTH_PROTOCOL_RFCOMM => decline - multiplexer already exists", l2cap_cid); 943 l2cap_decline_connection(l2cap_cid); 944 return 1; 945 } 946 947 // create and inititialize new multiplexer instance (incoming) 948 multiplexer = rfcomm_multiplexer_create_for_addr(event_addr); 949 if (!multiplexer){ 950 log_info("INCOMING_CONNECTION (l2cap_cid 0x%02x) for BLUETOOTH_PROTOCOL_RFCOMM => decline - no memory left", l2cap_cid); 951 l2cap_decline_connection(l2cap_cid); 952 return 1; 953 } 954 955 multiplexer->con_handle = con_handle; 956 multiplexer->l2cap_cid = l2cap_cid; 957 // 958 multiplexer->state = RFCOMM_MULTIPLEXER_W4_SABM_0; 959 log_info("L2CAP_EVENT_INCOMING_CONNECTION (l2cap_cid 0x%02x) for BLUETOOTH_PROTOCOL_RFCOMM => accept", l2cap_cid); 960 l2cap_accept_connection(l2cap_cid); 961 return 1; 962 963 // l2cap connection opened -> store l2cap_cid, remote_addr 964 case L2CAP_EVENT_CHANNEL_OPENED: 965 966 if (little_endian_read_16(packet, 11) != BLUETOOTH_PROTOCOL_RFCOMM) break; 967 968 status = packet[2]; 969 log_info("L2CAP_EVENT_CHANNEL_OPENED for BLUETOOTH_PROTOCOL_RFCOMM, status %u", status); 970 971 // get multiplexer for remote addr 972 con_handle = little_endian_read_16(packet, 9); 973 l2cap_cid = little_endian_read_16(packet, 13); 974 reverse_bd_addr(&packet[3], event_addr); 975 multiplexer = rfcomm_multiplexer_for_addr(event_addr); 976 if (!multiplexer) { 977 log_error("L2CAP_EVENT_CHANNEL_OPENED but no multiplexer prepared"); 978 return 1; 979 } 980 981 // on l2cap open error discard everything 982 if (status){ 983 984 // remove (potential) timer 985 rfcomm_multiplexer_stop_timer(multiplexer); 986 987 // mark multiplexer as shutting down 988 multiplexer->state = RFCOMM_MULTIPLEXER_SHUTTING_DOWN; 989 990 // emit rfcomm_channel_opened with status and free channel 991 int done = 0; 992 while (!done){ 993 btstack_linked_item_t * it = (btstack_linked_item_t *) &rfcomm_channels; 994 while (it->next) { 995 rfcomm_channel_t * channel = (rfcomm_channel_t *) it->next; 996 if (channel->multiplexer == multiplexer){ 997 rfcomm_emit_channel_opened(channel, status); 998 btstack_linked_list_remove(&rfcomm_channels, (btstack_linked_item_t *) channel); 999 btstack_memory_rfcomm_channel_free(channel); 1000 break; 1001 } else { 1002 it = it->next; 1003 } 1004 } 1005 } 1006 1007 // free multiplexer 1008 rfcomm_multiplexer_free(multiplexer); 1009 return 1; 1010 } 1011 1012 // following could be: rfcom_multiplexer_state_machein(..., EVENT_L2CAP_OPENED) 1013 1014 if (multiplexer->state == RFCOMM_MULTIPLEXER_W4_CONNECT) { 1015 log_info("L2CAP_EVENT_CHANNEL_OPENED: outgoing connection"); 1016 // wrong remote addr 1017 if (bd_addr_cmp(event_addr, multiplexer->remote_addr)) break; 1018 multiplexer->l2cap_cid = l2cap_cid; 1019 multiplexer->con_handle = con_handle; 1020 // send SABM #0 1021 rfcomm_multiplexer_set_state_and_request_can_send_now_event(multiplexer, RFCOMM_MULTIPLEXER_SEND_SABM_0); 1022 1023 } else { // multiplexer->state == RFCOMM_MULTIPLEXER_W4_SABM_0 1024 1025 // set max frame size based on l2cap MTU 1026 multiplexer->max_frame_size = rfcomm_max_frame_size_for_l2cap_mtu(little_endian_read_16(packet, 17)); 1027 } 1028 return 1; 1029 1030 // l2cap disconnect -> state = RFCOMM_MULTIPLEXER_CLOSED; 1031 1032 // Notify channel packet handler if they can send now 1033 case L2CAP_EVENT_CAN_SEND_NOW: 1034 l2cap_cid = l2cap_event_can_send_now_get_local_cid(packet); 1035 rfcomm_handle_can_send_now(l2cap_cid); 1036 return 1; 1037 1038 case L2CAP_EVENT_CHANNEL_CLOSED: 1039 // data: event (8), len(8), channel (16) 1040 l2cap_cid = little_endian_read_16(packet, 2); 1041 multiplexer = rfcomm_multiplexer_for_l2cap_cid(l2cap_cid); 1042 log_info("L2CAP_EVENT_CHANNEL_CLOSED cid 0x%0x, mult %p", l2cap_cid, multiplexer); 1043 if (!multiplexer) break; 1044 log_info("L2CAP_EVENT_CHANNEL_CLOSED state %u", multiplexer->state); 1045 // no need to call l2cap_disconnect here, as it's already closed 1046 rfcomm_multiplexer_finalize(multiplexer); 1047 return 1; 1048 1049 default: 1050 break; 1051 } 1052 return 0; 1053 } 1054 1055 static int rfcomm_multiplexer_l2cap_packet_handler(uint16_t channel, uint8_t *packet, uint16_t size){ 1056 // get or create a multiplexer for a certain device 1057 rfcomm_multiplexer_t *multiplexer = rfcomm_multiplexer_for_l2cap_cid(channel); 1058 if (!multiplexer) return 0; 1059 1060 uint16_t l2cap_cid = multiplexer->l2cap_cid; 1061 1062 // but only care for multiplexer control channel 1063 uint8_t frame_dlci = packet[0] >> 2; 1064 if (frame_dlci) return 0; 1065 const uint8_t length_offset = (packet[2] & 1) ^ 1; // to be used for pos >= 3 1066 const uint8_t credit_offset = ((packet[1] & BT_RFCOMM_UIH_PF) == BT_RFCOMM_UIH_PF) ? 1 : 0; // credits for uih_pf frames 1067 const uint8_t payload_offset = 3 + length_offset + credit_offset; 1068 switch (packet[1]){ 1069 1070 case BT_RFCOMM_SABM: 1071 if (multiplexer->state == RFCOMM_MULTIPLEXER_W4_SABM_0){ 1072 log_info("Received SABM #0"); 1073 multiplexer->outgoing = 0; 1074 rfcomm_multiplexer_set_state_and_request_can_send_now_event(multiplexer, RFCOMM_MULTIPLEXER_SEND_UA_0); 1075 return 1; 1076 } 1077 break; 1078 1079 case BT_RFCOMM_UA: 1080 if (multiplexer->state == RFCOMM_MULTIPLEXER_W4_UA_0) { 1081 // UA #0 -> send UA #0, state = RFCOMM_MULTIPLEXER_OPEN 1082 log_info("Received UA #0 "); 1083 rfcomm_multiplexer_opened(multiplexer); 1084 return 1; 1085 } 1086 break; 1087 1088 case BT_RFCOMM_DISC: 1089 // DISC #0 -> send UA #0, close multiplexer 1090 log_info("Received DISC #0, (ougoing = %u)", multiplexer->outgoing); 1091 rfcomm_multiplexer_set_state_and_request_can_send_now_event(multiplexer, RFCOMM_MULTIPLEXER_SEND_UA_0_AND_DISC); 1092 return 1; 1093 1094 case BT_RFCOMM_DM: 1095 // DM #0 - we shouldn't get this, just give up 1096 log_info("Received DM #0"); 1097 log_info("-> Closing down multiplexer"); 1098 rfcomm_multiplexer_finalize(multiplexer); 1099 l2cap_disconnect(l2cap_cid, 0x13); 1100 return 1; 1101 1102 case BT_RFCOMM_UIH: 1103 if (packet[payload_offset] == BT_RFCOMM_CLD_CMD){ 1104 // Multiplexer close down (CLD) -> close mutliplexer 1105 log_info("Received Multiplexer close down command"); 1106 log_info("-> Closing down multiplexer"); 1107 rfcomm_multiplexer_finalize(multiplexer); 1108 l2cap_disconnect(l2cap_cid, 0x13); 1109 return 1; 1110 } 1111 switch (packet[payload_offset]){ 1112 case BT_RFCOMM_CLD_CMD: 1113 // Multiplexer close down (CLD) -> close mutliplexer 1114 log_info("Received Multiplexer close down command"); 1115 log_info("-> Closing down multiplexer"); 1116 rfcomm_multiplexer_finalize(multiplexer); 1117 l2cap_disconnect(l2cap_cid, 0x13); 1118 return 1; 1119 1120 case BT_RFCOMM_FCON_CMD: 1121 multiplexer->fcon = 0x81; 1122 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1123 return 1; 1124 1125 case BT_RFCOMM_FCOFF_CMD: 1126 multiplexer->fcon = 0x80; 1127 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1128 return 1; 1129 1130 case BT_RFCOMM_TEST_CMD: { 1131 log_info("Received test command"); 1132 int len = packet[payload_offset+1] >> 1; // length < 125 1133 if (len > RFCOMM_TEST_DATA_MAX_LEN){ 1134 len = RFCOMM_TEST_DATA_MAX_LEN; 1135 } 1136 len = btstack_min(len, size - 1 - payload_offset); // avoid information leak 1137 multiplexer->test_data_len = len; 1138 memcpy(multiplexer->test_data, &packet[payload_offset + 2], len); 1139 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1140 return 1; 1141 } 1142 default: 1143 break; 1144 } 1145 break; 1146 1147 default: 1148 break; 1149 1150 } 1151 return 0; 1152 } 1153 1154 static int rfcomm_multiplexer_ready_to_send(rfcomm_multiplexer_t * multiplexer){ 1155 if (multiplexer->send_dm_for_dlci) return 1; 1156 if (multiplexer->nsc_command) return 1; 1157 if (multiplexer->fcon & 0x80) return 1; 1158 switch (multiplexer->state){ 1159 case RFCOMM_MULTIPLEXER_SEND_SABM_0: 1160 case RFCOMM_MULTIPLEXER_SEND_UA_0: 1161 case RFCOMM_MULTIPLEXER_SEND_UA_0_AND_DISC: 1162 return 1; 1163 case RFCOMM_MULTIPLEXER_OPEN: 1164 if (multiplexer->test_data_len) { 1165 return 1; 1166 } 1167 break; 1168 default: 1169 break; 1170 } 1171 return 0; 1172 } 1173 1174 static void rfcomm_multiplexer_state_machine(rfcomm_multiplexer_t * multiplexer, RFCOMM_MULTIPLEXER_EVENT event){ 1175 1176 if (event != MULT_EV_READY_TO_SEND) return; 1177 1178 uint16_t l2cap_cid = multiplexer->l2cap_cid; 1179 1180 // process stored DM responses 1181 if (multiplexer->send_dm_for_dlci){ 1182 uint8_t dlci = multiplexer->send_dm_for_dlci; 1183 multiplexer->send_dm_for_dlci = 0; 1184 rfcomm_send_dm_pf(multiplexer, dlci); 1185 return; 1186 } 1187 1188 if (multiplexer->nsc_command){ 1189 uint8_t command = multiplexer->nsc_command; 1190 multiplexer->nsc_command = 0; 1191 rfcomm_send_uih_nsc_rsp(multiplexer, command); 1192 return; 1193 } 1194 1195 if (multiplexer->fcon & 0x80){ 1196 multiplexer->fcon &= 0x01; 1197 rfcomm_send_uih_fc_rsp(multiplexer, multiplexer->fcon); 1198 1199 if (multiplexer->fcon == 0) return; 1200 // trigger client to send again after sending FCon Response 1201 rfcomm_notify_channel_can_send(); 1202 return; 1203 } 1204 1205 switch (multiplexer->state) { 1206 case RFCOMM_MULTIPLEXER_SEND_SABM_0: 1207 log_info("Sending SABM #0 - (multi 0x%p)", multiplexer); 1208 multiplexer->state = RFCOMM_MULTIPLEXER_W4_UA_0; 1209 rfcomm_send_sabm(multiplexer, 0); 1210 break; 1211 case RFCOMM_MULTIPLEXER_SEND_UA_0: 1212 log_info("Sending UA #0"); 1213 multiplexer->state = RFCOMM_MULTIPLEXER_OPEN; 1214 rfcomm_send_ua(multiplexer, 0); 1215 1216 rfcomm_multiplexer_opened(multiplexer); 1217 break; 1218 case RFCOMM_MULTIPLEXER_SEND_UA_0_AND_DISC: 1219 // try to detect authentication errors: drop link key if multiplexer closed before first channel got opened 1220 if (!multiplexer->at_least_one_connection){ 1221 log_info("TODO: no connections established - delete link key prophylactically"); 1222 // hci_send_cmd(&hci_delete_stored_link_key, multiplexer->remote_addr); 1223 } 1224 log_info("Sending UA #0"); 1225 log_info("Closing down multiplexer"); 1226 multiplexer->state = RFCOMM_MULTIPLEXER_CLOSED; 1227 rfcomm_send_ua(multiplexer, 0); 1228 1229 rfcomm_multiplexer_finalize(multiplexer); 1230 l2cap_disconnect(l2cap_cid, 0x13); 1231 break; 1232 case RFCOMM_MULTIPLEXER_OPEN: 1233 // respond to test command 1234 if (multiplexer->test_data_len){ 1235 int len = multiplexer->test_data_len; 1236 log_info("Sending TEST Response with %u bytes", len); 1237 multiplexer->test_data_len = 0; 1238 rfcomm_send_uih_test_rsp(multiplexer, multiplexer->test_data, len); 1239 return; 1240 } 1241 break; 1242 default: 1243 break; 1244 } 1245 } 1246 1247 // MARK: RFCOMM CHANNEL 1248 1249 static void rfcomm_channel_send_credits(rfcomm_channel_t *channel, uint8_t credits){ 1250 channel->credits_incoming += credits; 1251 rfcomm_send_uih_credits(channel->multiplexer, channel->dlci, credits); 1252 } 1253 1254 static int rfcomm_channel_can_send(rfcomm_channel_t * channel){ 1255 if (!channel->credits_outgoing) return 0; 1256 if ((channel->multiplexer->fcon & 1) == 0) return 0; 1257 return l2cap_can_send_packet_now(channel->multiplexer->l2cap_cid); 1258 } 1259 1260 static void rfcomm_channel_opened(rfcomm_channel_t *rfChannel){ 1261 1262 log_info("rfcomm_channel_opened!"); 1263 1264 rfChannel->state = RFCOMM_CHANNEL_OPEN; 1265 rfcomm_emit_channel_opened(rfChannel, 0); 1266 rfcomm_emit_port_configuration(rfChannel); 1267 1268 // remove (potential) timer 1269 rfcomm_multiplexer_t *multiplexer = rfChannel->multiplexer; 1270 if (multiplexer->timer_active) { 1271 btstack_run_loop_remove_timer(&multiplexer->timer); 1272 multiplexer->timer_active = 0; 1273 } 1274 // hack for problem detecting authentication failure 1275 multiplexer->at_least_one_connection = 1; 1276 1277 // request can send now if channel ready 1278 if (rfcomm_channel_ready_to_send(rfChannel)){ 1279 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1280 } 1281 } 1282 1283 static void rfcomm_channel_packet_handler_uih(rfcomm_multiplexer_t *multiplexer, uint8_t * packet, uint16_t size){ 1284 const uint8_t frame_dlci = packet[0] >> 2; 1285 const uint8_t length_offset = (packet[2] & 1) ^ 1; // to be used for pos >= 3 1286 const uint8_t credit_offset = ((packet[1] & BT_RFCOMM_UIH_PF) == BT_RFCOMM_UIH_PF) ? 1 : 0; // credits for uih_pf frames 1287 const uint8_t payload_offset = 3 + length_offset + credit_offset; 1288 1289 rfcomm_channel_t * channel = rfcomm_channel_for_multiplexer_and_dlci(multiplexer, frame_dlci); 1290 if (!channel) return; 1291 1292 // handle new outgoing credits 1293 if (packet[1] == BT_RFCOMM_UIH_PF) { 1294 1295 // add them 1296 uint16_t new_credits = packet[3+length_offset]; 1297 channel->credits_outgoing += new_credits; 1298 log_info( "RFCOMM data UIH_PF, new credits: %u, now %u", new_credits, channel->credits_outgoing); 1299 1300 // notify channel statemachine 1301 rfcomm_channel_event_t channel_event = { CH_EVT_RCVD_CREDITS, 0 }; 1302 rfcomm_channel_state_machine_with_channel(channel, &channel_event); 1303 if (rfcomm_channel_ready_to_send(channel)){ 1304 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1305 } 1306 } 1307 1308 // contains payload? 1309 if (size - 1 > payload_offset){ 1310 1311 // log_info( "RFCOMM data UIH_PF, size %u, channel %p", size-payload_offset-1, rfChannel->connection); 1312 1313 // decrease incoming credit counter 1314 if (channel->credits_incoming > 0){ 1315 channel->credits_incoming--; 1316 } 1317 1318 // deliver payload 1319 (channel->packet_handler)(RFCOMM_DATA_PACKET, channel->rfcomm_cid, 1320 &packet[payload_offset], size-payload_offset-1); 1321 } 1322 1323 // automatically provide new credits to remote device, if no incoming flow control 1324 if (!channel->incoming_flow_control && channel->credits_incoming < 5){ 1325 channel->new_credits_incoming = RFCOMM_CREDITS; 1326 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1327 } 1328 } 1329 1330 static void rfcomm_channel_accept_pn(rfcomm_channel_t *channel, rfcomm_channel_event_pn_t *event){ 1331 // priority of client request 1332 channel->pn_priority = event->priority; 1333 1334 // new credits 1335 channel->credits_outgoing = event->credits_outgoing; 1336 1337 // negotiate max frame size 1338 if (channel->max_frame_size > channel->multiplexer->max_frame_size) { 1339 channel->max_frame_size = channel->multiplexer->max_frame_size; 1340 } 1341 if (channel->max_frame_size > event->max_frame_size) { 1342 channel->max_frame_size = event->max_frame_size; 1343 } 1344 1345 } 1346 1347 static void rfcomm_channel_finalize(rfcomm_channel_t *channel){ 1348 1349 rfcomm_multiplexer_t *multiplexer = channel->multiplexer; 1350 1351 // remove from list 1352 btstack_linked_list_remove( &rfcomm_channels, (btstack_linked_item_t *) channel); 1353 1354 // free channel 1355 btstack_memory_rfcomm_channel_free(channel); 1356 1357 // update multiplexer timeout after channel was removed from list 1358 rfcomm_multiplexer_prepare_idle_timer(multiplexer); 1359 } 1360 1361 static void rfcomm_channel_state_machine_with_dlci(rfcomm_multiplexer_t * multiplexer, uint8_t dlci, const rfcomm_channel_event_t *event){ 1362 1363 // TODO: if client max frame size is smaller than RFCOMM_DEFAULT_SIZE, send PN 1364 1365 1366 // lookup existing channel 1367 rfcomm_channel_t * channel = rfcomm_channel_for_multiplexer_and_dlci(multiplexer, dlci); 1368 1369 // log_info("rfcomm_channel_state_machine_with_dlci lookup dlci #%u = 0x%08x - event %u", dlci, (int) channel, event->type); 1370 1371 if (channel) { 1372 rfcomm_channel_state_machine_with_channel(channel, event); 1373 if (rfcomm_channel_ready_to_send(channel)){ 1374 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1375 } 1376 return; 1377 } 1378 1379 // service registered? 1380 rfcomm_service_t * service = rfcomm_service_for_channel(dlci >> 1); 1381 // log_info("rfcomm_channel_state_machine_with_dlci service dlci #%u = 0x%08x", dlci, (int) service); 1382 if (!service) { 1383 // discard request by sending disconnected mode 1384 multiplexer->send_dm_for_dlci = dlci; 1385 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1386 return; 1387 } 1388 1389 // create channel for some events 1390 switch (event->type) { 1391 case CH_EVT_RCVD_SABM: 1392 case CH_EVT_RCVD_PN: 1393 case CH_EVT_RCVD_RPN_REQ: 1394 case CH_EVT_RCVD_RPN_CMD: 1395 // setup incoming channel 1396 channel = rfcomm_channel_create(multiplexer, service, dlci >> 1); 1397 if (!channel){ 1398 // discard request by sending disconnected mode 1399 multiplexer->send_dm_for_dlci = dlci; 1400 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1401 } 1402 break; 1403 default: 1404 break; 1405 } 1406 1407 if (!channel) { 1408 // discard request by sending disconnected mode 1409 multiplexer->send_dm_for_dlci = dlci; 1410 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1411 return; 1412 } 1413 1414 rfcomm_channel_state_machine_with_channel(channel, event); 1415 if (rfcomm_channel_ready_to_send(channel)){ 1416 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1417 } 1418 } 1419 1420 static void rfcomm_channel_packet_handler(rfcomm_multiplexer_t * multiplexer, uint8_t *packet, uint16_t size){ 1421 1422 UNUSED(size); // ok: fixed format messages 1423 1424 // rfcomm: (0) addr [76543 server channel] [2 direction: initiator uses 1] [1 C/R: CMD by initiator = 1] [0 EA=1] 1425 const uint8_t frame_dlci = packet[0] >> 2; 1426 uint8_t message_dlci; // used by commands in UIH(_PF) packets 1427 uint8_t message_len; // " 1428 1429 // rfcomm: (1) command/control 1430 // -- credits_offset = 1 if command == BT_RFCOMM_UIH_PF 1431 const uint8_t credit_offset = ((packet[1] & BT_RFCOMM_UIH_PF) == BT_RFCOMM_UIH_PF) ? 1 : 0; // credits for uih_pf frames 1432 // rfcomm: (2) length. if bit 0 is cleared, 2 byte length is used. (little endian) 1433 const uint8_t length_offset = (packet[2] & 1) ^ 1; // to be used for pos >= 3 1434 // rfcomm: (3+length_offset) credits if credits_offset == 1 1435 // rfcomm: (3+length_offest+credits_offset) 1436 const uint8_t payload_offset = 3 + length_offset + credit_offset; 1437 1438 rfcomm_channel_event_t event; 1439 rfcomm_channel_event_pn_t event_pn; 1440 rfcomm_channel_event_rpn_t event_rpn; 1441 rfcomm_channel_event_msc_t event_msc; 1442 1443 // switch by rfcomm message type 1444 switch(packet[1]) { 1445 1446 case BT_RFCOMM_SABM: 1447 event.type = CH_EVT_RCVD_SABM; 1448 log_info("Received SABM #%u", frame_dlci); 1449 rfcomm_channel_state_machine_with_dlci(multiplexer, frame_dlci, &event); 1450 break; 1451 1452 case BT_RFCOMM_UA: 1453 event.type = CH_EVT_RCVD_UA; 1454 log_info("Received UA #%u",frame_dlci); 1455 rfcomm_channel_state_machine_with_dlci(multiplexer, frame_dlci, &event); 1456 break; 1457 1458 case BT_RFCOMM_DISC: 1459 event.type = CH_EVT_RCVD_DISC; 1460 rfcomm_channel_state_machine_with_dlci(multiplexer, frame_dlci, &event); 1461 break; 1462 1463 case BT_RFCOMM_DM: 1464 case BT_RFCOMM_DM_PF: 1465 event.type = CH_EVT_RCVD_DM; 1466 rfcomm_channel_state_machine_with_dlci(multiplexer, frame_dlci, &event); 1467 break; 1468 1469 case BT_RFCOMM_UIH_PF: 1470 case BT_RFCOMM_UIH: 1471 1472 message_len = packet[payload_offset+1] >> 1; 1473 1474 switch (packet[payload_offset]) { 1475 case BT_RFCOMM_PN_CMD: 1476 message_dlci = packet[payload_offset+2]; 1477 event_pn.super.type = CH_EVT_RCVD_PN; 1478 event_pn.priority = packet[payload_offset+4]; 1479 event_pn.max_frame_size = little_endian_read_16(packet, payload_offset+6); 1480 event_pn.credits_outgoing = packet[payload_offset+9]; 1481 log_info("Received UIH Parameter Negotiation Command for #%u, credits %u", 1482 message_dlci, event_pn.credits_outgoing); 1483 rfcomm_channel_state_machine_with_dlci(multiplexer, message_dlci, (rfcomm_channel_event_t*) &event_pn); 1484 break; 1485 1486 case BT_RFCOMM_PN_RSP: 1487 message_dlci = packet[payload_offset+2]; 1488 event_pn.super.type = CH_EVT_RCVD_PN_RSP; 1489 event_pn.priority = packet[payload_offset+4]; 1490 event_pn.max_frame_size = little_endian_read_16(packet, payload_offset+6); 1491 event_pn.credits_outgoing = packet[payload_offset+9]; 1492 log_info("Received UIH Parameter Negotiation Response max frame %u, credits %u", 1493 event_pn.max_frame_size, event_pn.credits_outgoing); 1494 rfcomm_channel_state_machine_with_dlci(multiplexer, message_dlci, (rfcomm_channel_event_t*) &event_pn); 1495 break; 1496 1497 case BT_RFCOMM_MSC_CMD: 1498 message_dlci = packet[payload_offset+2] >> 2; 1499 event_msc.super.type = CH_EVT_RCVD_MSC_CMD; 1500 event_msc.modem_status = packet[payload_offset+3]; 1501 log_info("Received MSC CMD for #%u, ", message_dlci); 1502 rfcomm_channel_state_machine_with_dlci(multiplexer, message_dlci, (rfcomm_channel_event_t*) &event_msc); 1503 break; 1504 1505 case BT_RFCOMM_MSC_RSP: 1506 message_dlci = packet[payload_offset+2] >> 2; 1507 event.type = CH_EVT_RCVD_MSC_RSP; 1508 log_info("Received MSC RSP for #%u", message_dlci); 1509 rfcomm_channel_state_machine_with_dlci(multiplexer, message_dlci, &event); 1510 break; 1511 1512 case BT_RFCOMM_RPN_CMD: 1513 message_dlci = packet[payload_offset+2] >> 2; 1514 switch (message_len){ 1515 case 1: 1516 log_info("Received Remote Port Negotiation Request for #%u", message_dlci); 1517 event.type = CH_EVT_RCVD_RPN_REQ; 1518 rfcomm_channel_state_machine_with_dlci(multiplexer, message_dlci, &event); 1519 break; 1520 case 8: 1521 log_info("Received Remote Port Negotiation Update for #%u", message_dlci); 1522 event_rpn.super.type = CH_EVT_RCVD_RPN_CMD; 1523 event_rpn.data = *(rfcomm_rpn_data_t*) &packet[payload_offset+3]; 1524 rfcomm_channel_state_machine_with_dlci(multiplexer, message_dlci, (rfcomm_channel_event_t*) &event_rpn); 1525 break; 1526 default: 1527 break; 1528 } 1529 break; 1530 1531 case BT_RFCOMM_RPN_RSP: 1532 log_info("Received RPN response"); 1533 break; 1534 1535 case BT_RFCOMM_RLS_CMD: { 1536 log_info("Received RLS command"); 1537 message_dlci = packet[payload_offset+2] >> 2; 1538 rfcomm_channel_event_rls_t event_rls; 1539 event_rls.super.type = CH_EVT_RCVD_RLS_CMD; 1540 event_rls.line_status = packet[payload_offset+3]; 1541 rfcomm_channel_state_machine_with_dlci(multiplexer, message_dlci, (rfcomm_channel_event_t*) &event_rls); 1542 break; 1543 } 1544 1545 case BT_RFCOMM_RLS_RSP: 1546 log_info("Received RLS response"); 1547 break; 1548 1549 // Following commands are handled by rfcomm_multiplexer_l2cap_packet_handler 1550 // case BT_RFCOMM_TEST_CMD: 1551 // case BT_RFCOMM_FCOFF_CMD: 1552 // case BT_RFCOMM_FCON_CMD: 1553 // everything else is an not supported command 1554 default: { 1555 log_error("Received unknown UIH command packet - 0x%02x", packet[payload_offset]); 1556 multiplexer->nsc_command = packet[payload_offset]; 1557 break; 1558 } 1559 } 1560 break; 1561 1562 default: 1563 log_error("Received unknown RFCOMM message type %x", packet[1]); 1564 break; 1565 } 1566 1567 // trigger next action - example W4_PN_RSP: transition to SEND_SABM which only depends on "can send" 1568 if (rfcomm_multiplexer_ready_to_send(multiplexer)){ 1569 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 1570 } 1571 } 1572 1573 static void rfcomm_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 1574 1575 if (packet_type == HCI_EVENT_PACKET){ 1576 rfcomm_hci_event_handler(packet, size); 1577 return; 1578 } 1579 1580 // we only handle l2cap packets for: 1581 if (packet_type != L2CAP_DATA_PACKET) return; 1582 1583 // - multiplexer itself 1584 int handled = rfcomm_multiplexer_l2cap_packet_handler(channel, packet, size); 1585 1586 if (handled) return; 1587 1588 // - channel over open mutliplexer 1589 rfcomm_multiplexer_t * multiplexer = rfcomm_multiplexer_for_l2cap_cid(channel); 1590 if (!multiplexer || multiplexer->state != RFCOMM_MULTIPLEXER_OPEN) return; 1591 1592 // channel data ? 1593 // rfcomm: (0) addr [76543 server channel] [2 direction: initiator uses 1] [1 C/R: CMD by initiator = 1] [0 EA=1] 1594 const uint8_t frame_dlci = packet[0] >> 2; 1595 1596 if (frame_dlci && (packet[1] == BT_RFCOMM_UIH || packet[1] == BT_RFCOMM_UIH_PF)) { 1597 rfcomm_channel_packet_handler_uih(multiplexer, packet, size); 1598 return; 1599 } 1600 1601 rfcomm_channel_packet_handler(multiplexer, packet, size); 1602 } 1603 1604 static int rfcomm_channel_ready_for_open(rfcomm_channel_t *channel){ 1605 // note: exchanging MSC isn't neccessary to consider channel open 1606 // note: having outgoing credits is also not necessary to consider channel open 1607 // 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); 1608 // if ((channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SENT_MSC_RSP) == 0) return 0; 1609 // if (channel->credits_outgoing == 0) return 0; 1610 log_info("rfcomm_channel_ready_for_open state %u, flags needed %04x, current %04x, rf credits %u", 1611 channel->state, RFCOMM_CHANNEL_STATE_VAR_RCVD_MSC_RSP, channel->state_var, channel->credits_outgoing); 1612 if ((channel->state_var & RFCOMM_CHANNEL_STATE_VAR_RCVD_MSC_RSP) == 0) return 0; 1613 if ((channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SENT_CREDITS) == 0) return 0; 1614 1615 return 1; 1616 } 1617 1618 static int rfcomm_channel_ready_for_incoming_dlc_setup(rfcomm_channel_t * channel){ 1619 log_info("rfcomm_channel_ready_for_incoming_dlc_setup state var %04x", channel->state_var); 1620 // Client accept and SABM/UA is required, PN RSP is needed if PN was received 1621 if ((channel->state_var & RFCOMM_CHANNEL_STATE_VAR_CLIENT_ACCEPTED) == 0) return 0; 1622 if ((channel->state_var & RFCOMM_CHANNEL_STATE_VAR_RCVD_SABM ) == 0) return 0; 1623 if ((channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SEND_UA ) != 0) return 0; 1624 if ((channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SEND_PN_RSP ) != 0) return 0; 1625 return 1; 1626 } 1627 1628 inline static void rfcomm_channel_state_add(rfcomm_channel_t *channel, RFCOMM_CHANNEL_STATE_VAR event){ 1629 channel->state_var = (RFCOMM_CHANNEL_STATE_VAR) (channel->state_var | event); 1630 } 1631 inline static void rfcomm_channel_state_remove(rfcomm_channel_t *channel, RFCOMM_CHANNEL_STATE_VAR event){ 1632 channel->state_var = (RFCOMM_CHANNEL_STATE_VAR) (channel->state_var & ~event); 1633 } 1634 1635 static int rfcomm_channel_ready_to_send(rfcomm_channel_t * channel){ 1636 switch (channel->state){ 1637 case RFCOMM_CHANNEL_SEND_UIH_PN: 1638 log_debug("ch-ready: state %u", channel->state); 1639 return 1; 1640 case RFCOMM_CHANNEL_SEND_SABM_W4_UA: 1641 log_debug("ch-ready: state %u", channel->state); 1642 return 1; 1643 case RFCOMM_CHANNEL_SEND_UA_AFTER_DISC: 1644 log_debug("ch-ready: state %u", channel->state); 1645 return 1; 1646 case RFCOMM_CHANNEL_SEND_DISC: 1647 log_debug("ch-ready: state %u", channel->state); 1648 return 1; 1649 case RFCOMM_CHANNEL_SEND_DM: 1650 log_debug("ch-ready: state %u", channel->state); 1651 return 1; 1652 case RFCOMM_CHANNEL_OPEN: 1653 if (channel->new_credits_incoming) { 1654 log_debug("ch-ready: channel open & new_credits_incoming") ; 1655 return 1; 1656 } 1657 break; 1658 case RFCOMM_CHANNEL_DLC_SETUP: 1659 if (channel->state_var & ( 1660 RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_CMD | 1661 RFCOMM_CHANNEL_STATE_VAR_SEND_CREDITS 1662 )) { 1663 log_debug("ch-ready: channel dlc setup & send msc cmd or send credits") ; 1664 return 1; 1665 } 1666 break; 1667 1668 default: 1669 break; 1670 } 1671 1672 if (channel->state_var & ( 1673 RFCOMM_CHANNEL_STATE_VAR_SEND_PN_RSP | 1674 RFCOMM_CHANNEL_STATE_VAR_SEND_RPN_INFO | 1675 RFCOMM_CHANNEL_STATE_VAR_SEND_RPN_RSP | 1676 RFCOMM_CHANNEL_STATE_VAR_SEND_UA | 1677 RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_RSP 1678 )){ 1679 log_debug("ch-ready: state %x, state var %x", channel->state, channel->state_var); 1680 return 1; 1681 } 1682 1683 if (channel->rls_line_status != RFCOMM_RLS_STATUS_INVALID) { 1684 log_debug("ch-ready: rls_line_status"); 1685 return 1; 1686 } 1687 1688 return 0; 1689 } 1690 1691 1692 static void rfcomm_channel_state_machine_with_channel(rfcomm_channel_t *channel, const rfcomm_channel_event_t *event){ 1693 1694 // log_info("rfcomm_channel_state_machine_with_channel: state %u, state_var %04x, event %u", channel->state, channel->state_var ,event->type); 1695 1696 rfcomm_multiplexer_t *multiplexer = channel->multiplexer; 1697 1698 // TODO: integrate in common switch 1699 if (event->type == CH_EVT_RCVD_DISC){ 1700 rfcomm_emit_channel_closed(channel); 1701 channel->state = RFCOMM_CHANNEL_SEND_UA_AFTER_DISC; 1702 return; 1703 } 1704 1705 // TODO: integrate in common switch 1706 if (event->type == CH_EVT_RCVD_DM){ 1707 log_info("Received DM message for #%u", channel->dlci); 1708 log_info("-> Closing channel locally for #%u", channel->dlci); 1709 rfcomm_emit_channel_closed(channel); 1710 rfcomm_channel_finalize(channel); 1711 return; 1712 } 1713 1714 // remote port negotiation command - just accept everything for now 1715 // 1716 // "The RPN command can be used before a new DLC is opened and should be used whenever the port settings change." 1717 // "The RPN command is specified as optional in TS 07.10, but it is mandatory to recognize and respond to it in RFCOMM. 1718 // (Although the handling of individual settings are implementation-dependent.)" 1719 // 1720 1721 // TODO: integrate in common switch 1722 if (event->type == CH_EVT_RCVD_RPN_CMD){ 1723 // control port parameters 1724 rfcomm_channel_event_rpn_t *event_rpn = (rfcomm_channel_event_rpn_t*) event; 1725 rfcomm_rpn_data_update(&channel->rpn_data, &event_rpn->data); 1726 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_RPN_RSP); 1727 // notify client about new settings 1728 rfcomm_emit_port_configuration(channel); 1729 return; 1730 } 1731 1732 // TODO: integrate in common switch 1733 if (event->type == CH_EVT_RCVD_RPN_REQ){ 1734 // no values got accepted (no values have beens sent) 1735 channel->rpn_data.parameter_mask_0 = 0x00; 1736 channel->rpn_data.parameter_mask_1 = 0x00; 1737 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_RPN_RSP); 1738 return; 1739 } 1740 1741 if (event->type == CH_EVT_RCVD_RLS_CMD){ 1742 rfcomm_channel_event_rls_t * event_rls = (rfcomm_channel_event_rls_t*) event; 1743 channel->rls_line_status = event_rls->line_status & 0x0f; 1744 log_info("CH_EVT_RCVD_RLS_CMD setting line status to 0x%0x", channel->rls_line_status); 1745 rfcomm_emit_remote_line_status(channel, event_rls->line_status); 1746 return; 1747 } 1748 1749 // TODO: integrate in common switch 1750 if (event->type == CH_EVT_READY_TO_SEND){ 1751 if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SEND_RPN_RSP){ 1752 log_info("Sending Remote Port Negotiation RSP for #%u", channel->dlci); 1753 rfcomm_channel_state_remove(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_RPN_RSP); 1754 rfcomm_send_uih_rpn_rsp(multiplexer, channel->dlci, &channel->rpn_data); 1755 return; 1756 } 1757 if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_RSP){ 1758 log_info("Sending MSC RSP for #%u", channel->dlci); 1759 rfcomm_channel_state_remove(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_RSP); 1760 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SENT_MSC_RSP); 1761 rfcomm_send_uih_msc_rsp(multiplexer, channel->dlci, 0x8d); // ea=1,fc=0,rtc=1,rtr=1,ic=0,dv=1 1762 return; 1763 } 1764 if (channel->rls_line_status != RFCOMM_RLS_STATUS_INVALID){ 1765 log_info("Sending RLS RSP 0x%0x", channel->rls_line_status); 1766 uint8_t line_status = channel->rls_line_status; 1767 channel->rls_line_status = RFCOMM_RLS_STATUS_INVALID; 1768 rfcomm_send_uih_rls_rsp(multiplexer, channel->dlci, line_status); 1769 return; 1770 } 1771 } 1772 1773 // emit MSC status to app 1774 if (event->type == CH_EVT_RCVD_MSC_CMD){ 1775 // notify client about new settings 1776 rfcomm_channel_event_msc_t *event_msc = (rfcomm_channel_event_msc_t*) event; 1777 uint8_t modem_status_event[2+1]; 1778 modem_status_event[0] = RFCOMM_EVENT_REMOTE_MODEM_STATUS; 1779 modem_status_event[1] = 1; 1780 modem_status_event[2] = event_msc->modem_status; 1781 (channel->packet_handler)(HCI_EVENT_PACKET, channel->rfcomm_cid, (uint8_t*)&modem_status_event, sizeof(modem_status_event)); 1782 // no return, MSC_CMD will be handled by state machine below 1783 } 1784 1785 rfcomm_channel_event_pn_t * event_pn = (rfcomm_channel_event_pn_t*) event; 1786 1787 switch (channel->state) { 1788 case RFCOMM_CHANNEL_CLOSED: 1789 switch (event->type){ 1790 case CH_EVT_RCVD_SABM: 1791 log_info("-> Inform app"); 1792 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_RCVD_SABM); 1793 channel->state = RFCOMM_CHANNEL_INCOMING_SETUP; 1794 rfcomm_emit_connection_request(channel); 1795 break; 1796 case CH_EVT_RCVD_PN: 1797 rfcomm_channel_accept_pn(channel, event_pn); 1798 log_info("-> Inform app"); 1799 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_RCVD_PN); 1800 channel->state = RFCOMM_CHANNEL_INCOMING_SETUP; 1801 rfcomm_emit_connection_request(channel); 1802 break; 1803 default: 1804 break; 1805 } 1806 break; 1807 1808 case RFCOMM_CHANNEL_INCOMING_SETUP: 1809 switch (event->type){ 1810 case CH_EVT_RCVD_SABM: 1811 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_RCVD_SABM); 1812 if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_CLIENT_ACCEPTED) { 1813 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_UA); 1814 } 1815 break; 1816 case CH_EVT_RCVD_PN: 1817 rfcomm_channel_accept_pn(channel, event_pn); 1818 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_RCVD_PN); 1819 if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_CLIENT_ACCEPTED) { 1820 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_PN_RSP); 1821 } 1822 break; 1823 case CH_EVT_READY_TO_SEND: 1824 // if / else if is used to check for state transition after sending 1825 if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SEND_PN_RSP){ 1826 log_info("Sending UIH Parameter Negotiation Respond for #%u", channel->dlci); 1827 rfcomm_channel_state_remove(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_PN_RSP); 1828 rfcomm_send_uih_pn_response(multiplexer, channel->dlci, channel->pn_priority, channel->max_frame_size); 1829 } else if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SEND_UA){ 1830 log_info("Sending UA #%u", channel->dlci); 1831 rfcomm_channel_state_remove(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_UA); 1832 rfcomm_send_ua(multiplexer, channel->dlci); 1833 } 1834 if (rfcomm_channel_ready_for_incoming_dlc_setup(channel)){ 1835 log_info("Incomping setup done, requesting send MSC CMD and send Credits"); 1836 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_CMD); 1837 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_CREDITS); 1838 channel->state = RFCOMM_CHANNEL_DLC_SETUP; 1839 } 1840 break; 1841 default: 1842 break; 1843 } 1844 break; 1845 1846 case RFCOMM_CHANNEL_W4_MULTIPLEXER: 1847 switch (event->type) { 1848 case CH_EVT_MULTIPLEXER_READY: 1849 log_info("Muliplexer opened, sending UIH PN next"); 1850 channel->state = RFCOMM_CHANNEL_SEND_UIH_PN; 1851 break; 1852 default: 1853 break; 1854 } 1855 break; 1856 1857 case RFCOMM_CHANNEL_SEND_UIH_PN: 1858 switch (event->type) { 1859 case CH_EVT_READY_TO_SEND: 1860 log_info("Sending UIH Parameter Negotiation Command for #%u (channel 0x%p)", channel->dlci, channel ); 1861 channel->state = RFCOMM_CHANNEL_W4_PN_RSP; 1862 rfcomm_send_uih_pn_command(multiplexer, channel->dlci, channel->max_frame_size); 1863 break; 1864 default: 1865 break; 1866 } 1867 break; 1868 1869 case RFCOMM_CHANNEL_W4_PN_RSP: 1870 switch (event->type){ 1871 case CH_EVT_RCVD_PN_RSP: 1872 // update max frame size 1873 if (channel->max_frame_size > event_pn->max_frame_size) { 1874 channel->max_frame_size = event_pn->max_frame_size; 1875 } 1876 // new credits 1877 channel->credits_outgoing = event_pn->credits_outgoing; 1878 channel->state = RFCOMM_CHANNEL_SEND_SABM_W4_UA; 1879 break; 1880 default: 1881 break; 1882 } 1883 break; 1884 1885 case RFCOMM_CHANNEL_SEND_SABM_W4_UA: 1886 switch (event->type) { 1887 case CH_EVT_READY_TO_SEND: 1888 log_info("Sending SABM #%u", channel->dlci); 1889 channel->state = RFCOMM_CHANNEL_W4_UA; 1890 rfcomm_send_sabm(multiplexer, channel->dlci); 1891 break; 1892 default: 1893 break; 1894 } 1895 break; 1896 1897 case RFCOMM_CHANNEL_W4_UA: 1898 switch (event->type){ 1899 case CH_EVT_RCVD_UA: 1900 channel->state = RFCOMM_CHANNEL_DLC_SETUP; 1901 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_CMD); 1902 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_CREDITS); 1903 break; 1904 default: 1905 break; 1906 } 1907 break; 1908 1909 case RFCOMM_CHANNEL_DLC_SETUP: 1910 switch (event->type){ 1911 case CH_EVT_RCVD_MSC_CMD: 1912 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_RCVD_MSC_CMD); 1913 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_RSP); 1914 break; 1915 case CH_EVT_RCVD_MSC_RSP: 1916 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_RCVD_MSC_RSP); 1917 break; 1918 1919 case CH_EVT_READY_TO_SEND: 1920 if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_CMD){ 1921 log_info("Sending MSC CMD for #%u", channel->dlci); 1922 rfcomm_channel_state_remove(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_CMD); 1923 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SENT_MSC_CMD); 1924 rfcomm_send_uih_msc_cmd(multiplexer, channel->dlci , 0x8d); // ea=1,fc=0,rtc=1,rtr=1,ic=0,dv=1 1925 break; 1926 } 1927 if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_SEND_CREDITS){ 1928 log_info("Providing credits for #%u", channel->dlci); 1929 rfcomm_channel_state_remove(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_CREDITS); 1930 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SENT_CREDITS); 1931 1932 if (channel->new_credits_incoming) { 1933 uint8_t new_credits = channel->new_credits_incoming; 1934 channel->new_credits_incoming = 0; 1935 rfcomm_channel_send_credits(channel, new_credits); 1936 } 1937 break; 1938 1939 } 1940 break; 1941 default: 1942 break; 1943 } 1944 // finally done? 1945 if (rfcomm_channel_ready_for_open(channel)){ 1946 channel->state = RFCOMM_CHANNEL_OPEN; 1947 rfcomm_channel_opened(channel); 1948 } 1949 break; 1950 1951 case RFCOMM_CHANNEL_OPEN: 1952 switch (event->type){ 1953 case CH_EVT_RCVD_MSC_CMD: 1954 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_RSP); 1955 break; 1956 case CH_EVT_READY_TO_SEND: 1957 if (channel->new_credits_incoming) { 1958 uint8_t new_credits = channel->new_credits_incoming; 1959 channel->new_credits_incoming = 0; 1960 rfcomm_channel_send_credits(channel, new_credits); 1961 break; 1962 } 1963 break; 1964 case CH_EVT_RCVD_CREDITS: 1965 rfcomm_notify_channel_can_send(); 1966 break; 1967 default: 1968 break; 1969 } 1970 break; 1971 1972 case RFCOMM_CHANNEL_SEND_DM: 1973 switch (event->type) { 1974 case CH_EVT_READY_TO_SEND: 1975 log_info("Sending DM_PF for #%u", channel->dlci); 1976 // don't emit channel closed - channel was never open 1977 channel->state = RFCOMM_CHANNEL_CLOSED; 1978 rfcomm_send_dm_pf(multiplexer, channel->dlci); 1979 rfcomm_channel_finalize(channel); 1980 break; 1981 default: 1982 break; 1983 } 1984 break; 1985 1986 case RFCOMM_CHANNEL_SEND_DISC: 1987 switch (event->type) { 1988 case CH_EVT_READY_TO_SEND: 1989 channel->state = RFCOMM_CHANNEL_W4_UA_AFTER_UA; 1990 rfcomm_send_disc(multiplexer, channel->dlci); 1991 break; 1992 default: 1993 break; 1994 } 1995 break; 1996 1997 case RFCOMM_CHANNEL_W4_UA_AFTER_UA: 1998 switch (event->type){ 1999 case CH_EVT_RCVD_UA: 2000 channel->state = RFCOMM_CHANNEL_CLOSED; 2001 rfcomm_emit_channel_closed(channel); 2002 rfcomm_channel_finalize(channel); 2003 break; 2004 default: 2005 break; 2006 } 2007 break; 2008 2009 case RFCOMM_CHANNEL_SEND_UA_AFTER_DISC: 2010 switch (event->type) { 2011 case CH_EVT_READY_TO_SEND: 2012 log_info("Sending UA after DISC for #%u", channel->dlci); 2013 channel->state = RFCOMM_CHANNEL_CLOSED; 2014 rfcomm_send_ua(multiplexer, channel->dlci); 2015 rfcomm_channel_finalize(channel); 2016 break; 2017 default: 2018 break; 2019 } 2020 break; 2021 2022 default: 2023 break; 2024 } 2025 } 2026 2027 // MARK: RFCOMM BTstack API 2028 2029 void rfcomm_init(void){ 2030 rfcomm_client_cid_generator = 0; 2031 rfcomm_multiplexers = NULL; 2032 rfcomm_services = NULL; 2033 rfcomm_channels = NULL; 2034 rfcomm_security_level = LEVEL_2; 2035 } 2036 2037 void rfcomm_set_required_security_level(gap_security_level_t security_level){ 2038 rfcomm_security_level = security_level; 2039 } 2040 2041 int rfcomm_can_send_packet_now(uint16_t rfcomm_cid){ 2042 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2043 if (!channel){ 2044 log_error("rfcomm_send cid 0x%02x doesn't exist!", rfcomm_cid); 2045 return 0; 2046 } 2047 return rfcomm_channel_can_send(channel); 2048 } 2049 2050 void rfcomm_request_can_send_now_event(uint16_t rfcomm_cid){ 2051 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2052 if (!channel){ 2053 log_error("rfcomm_send cid 0x%02x doesn't exist!", rfcomm_cid); 2054 return; 2055 } 2056 channel->waiting_for_can_send_now = 1; 2057 l2cap_request_can_send_now_event(channel->multiplexer->l2cap_cid); 2058 } 2059 2060 static int rfcomm_assert_send_valid(rfcomm_channel_t * channel , uint16_t len){ 2061 if (len > channel->max_frame_size){ 2062 log_error("rfcomm_send cid 0x%02x, rfcomm data lenght exceeds MTU!", channel->rfcomm_cid); 2063 return RFCOMM_DATA_LEN_EXCEEDS_MTU; 2064 } 2065 2066 if (!channel->credits_outgoing){ 2067 log_info("rfcomm_send cid 0x%02x, no rfcomm outgoing credits!", channel->rfcomm_cid); 2068 return RFCOMM_NO_OUTGOING_CREDITS; 2069 } 2070 2071 if ((channel->multiplexer->fcon & 1) == 0){ 2072 log_info("rfcomm_send cid 0x%02x, aggregate flow off!", channel->rfcomm_cid); 2073 return RFCOMM_AGGREGATE_FLOW_OFF; 2074 } 2075 return 0; 2076 } 2077 2078 // pre: rfcomm_can_send_packet_now(rfcomm_cid) == true 2079 int rfcomm_reserve_packet_buffer(void){ 2080 return l2cap_reserve_packet_buffer(); 2081 } 2082 2083 void rfcomm_release_packet_buffer(void){ 2084 l2cap_release_packet_buffer(); 2085 } 2086 2087 uint8_t * rfcomm_get_outgoing_buffer(void){ 2088 uint8_t * rfcomm_out_buffer = l2cap_get_outgoing_buffer(); 2089 // address + control + length (16) + no credit field 2090 return &rfcomm_out_buffer[4]; 2091 } 2092 2093 uint16_t rfcomm_get_max_frame_size(uint16_t rfcomm_cid){ 2094 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2095 if (!channel){ 2096 log_error("rfcomm_get_max_frame_size cid 0x%02x doesn't exist!", rfcomm_cid); 2097 return 0; 2098 } 2099 return channel->max_frame_size; 2100 } 2101 2102 int rfcomm_send_prepared(uint16_t rfcomm_cid, uint16_t len){ 2103 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2104 if (!channel){ 2105 log_error("rfcomm_send_prepared cid 0x%02x doesn't exist!", rfcomm_cid); 2106 return 0; 2107 } 2108 2109 int err = rfcomm_assert_send_valid(channel, len); 2110 if (err) return err; 2111 if (!l2cap_can_send_prepared_packet_now(channel->multiplexer->l2cap_cid)){ 2112 log_error("rfcomm_send_prepared: l2cap cannot send now"); 2113 return BTSTACK_ACL_BUFFERS_FULL; 2114 } 2115 2116 // send might cause l2cap to emit new credits, update counters first 2117 if (len){ 2118 channel->credits_outgoing--; 2119 } else { 2120 log_info("sending empty RFCOMM packet for cid %02x", rfcomm_cid); 2121 } 2122 2123 int result = rfcomm_send_uih_prepared(channel->multiplexer, channel->dlci, len); 2124 2125 if (result != 0) { 2126 if (len) { 2127 channel->credits_outgoing++; 2128 } 2129 log_error("rfcomm_send_prepared: error %d", result); 2130 return result; 2131 } 2132 2133 return result; 2134 } 2135 2136 int rfcomm_send(uint16_t rfcomm_cid, uint8_t *data, uint16_t len){ 2137 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2138 if (!channel){ 2139 log_error("cid 0x%02x doesn't exist!", rfcomm_cid); 2140 return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 2141 } 2142 2143 int err = rfcomm_assert_send_valid(channel, len); 2144 if (err) return err; 2145 if (!l2cap_can_send_packet_now(channel->multiplexer->l2cap_cid)){ 2146 log_error("rfcomm_send_internal: l2cap cannot send now"); 2147 return BTSTACK_ACL_BUFFERS_FULL; 2148 } 2149 2150 rfcomm_reserve_packet_buffer(); 2151 uint8_t * rfcomm_payload = rfcomm_get_outgoing_buffer(); 2152 memcpy(rfcomm_payload, data, len); 2153 err = rfcomm_send_prepared(rfcomm_cid, len); 2154 if (err){ 2155 rfcomm_release_packet_buffer(); 2156 } 2157 return err; 2158 } 2159 2160 // Sends Local Lnie Status, see LINE_STATUS_.. 2161 int rfcomm_send_local_line_status(uint16_t rfcomm_cid, uint8_t line_status){ 2162 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2163 if (!channel){ 2164 log_error("rfcomm_send_local_line_status cid 0x%02x doesn't exist!", rfcomm_cid); 2165 return 0; 2166 } 2167 return rfcomm_send_uih_rls_cmd(channel->multiplexer, channel->dlci, line_status); 2168 } 2169 2170 // Sned local modem status. see MODEM_STAUS_.. 2171 int rfcomm_send_modem_status(uint16_t rfcomm_cid, uint8_t modem_status){ 2172 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2173 if (!channel){ 2174 log_error("rfcomm_send_modem_status cid 0x%02x doesn't exist!", rfcomm_cid); 2175 return 0; 2176 } 2177 return rfcomm_send_uih_msc_cmd(channel->multiplexer, channel->dlci, modem_status); 2178 } 2179 2180 // Configure remote port 2181 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){ 2182 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2183 if (!channel){ 2184 log_error("rfcomm_send_port_configuration cid 0x%02x doesn't exist!", rfcomm_cid); 2185 return 0; 2186 } 2187 rfcomm_rpn_data_t rpn_data; 2188 rpn_data.baud_rate = baud_rate; 2189 rpn_data.flags = data_bits | (stop_bits << 2) | (parity << 3); 2190 rpn_data.flow_control = flow_control; 2191 rpn_data.xon = 0; 2192 rpn_data.xoff = 0; 2193 rpn_data.parameter_mask_0 = 0x1f; // all but xon/xoff 2194 rpn_data.parameter_mask_1 = 0x3f; // all flow control options 2195 return rfcomm_send_uih_rpn_cmd(channel->multiplexer, channel->dlci, &rpn_data); 2196 } 2197 2198 // Query remote port 2199 int rfcomm_query_port_configuration(uint16_t rfcomm_cid){ 2200 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2201 if (!channel){ 2202 log_error("rfcomm_query_port_configuration cid 0x%02x doesn't exist!", rfcomm_cid); 2203 return 0; 2204 } 2205 return rfcomm_send_uih_rpn_req(channel->multiplexer, channel->dlci); 2206 } 2207 2208 2209 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){ 2210 log_info("RFCOMM_CREATE_CHANNEL addr %s channel #%u init credits %u", bd_addr_to_str(addr), server_channel, initial_credits); 2211 2212 // create new multiplexer if necessary 2213 uint8_t status = 0; 2214 uint8_t dlci = 0; 2215 int new_multiplexer = 0; 2216 rfcomm_channel_t * channel = NULL; 2217 rfcomm_multiplexer_t * multiplexer = rfcomm_multiplexer_for_addr(addr); 2218 if (!multiplexer) { 2219 multiplexer = rfcomm_multiplexer_create_for_addr(addr); 2220 if (!multiplexer){ 2221 status = BTSTACK_MEMORY_ALLOC_FAILED; 2222 goto fail; 2223 } 2224 multiplexer->outgoing = 1; 2225 multiplexer->state = RFCOMM_MULTIPLEXER_W4_CONNECT; 2226 new_multiplexer = 1; 2227 } 2228 2229 // check if channel for this remote service already exists 2230 dlci = (server_channel << 1) | (multiplexer->outgoing ^ 1); 2231 channel = rfcomm_channel_for_multiplexer_and_dlci(multiplexer, dlci); 2232 if (channel){ 2233 status = RFCOMM_CHANNEL_ALREADY_REGISTERED; 2234 goto fail; 2235 } 2236 2237 // prepare channel 2238 channel = rfcomm_channel_create(multiplexer, NULL, server_channel); 2239 if (!channel){ 2240 status = BTSTACK_MEMORY_ALLOC_FAILED; 2241 goto fail; 2242 } 2243 2244 // rfcomm_cid is already assigned by rfcomm_channel_create 2245 channel->incoming_flow_control = incoming_flow_control; 2246 channel->new_credits_incoming = initial_credits; 2247 channel->packet_handler = packet_handler; 2248 2249 // return rfcomm_cid 2250 if (out_rfcomm_cid){ 2251 *out_rfcomm_cid = channel->rfcomm_cid; 2252 } 2253 2254 // start multiplexer setup 2255 if (multiplexer->state != RFCOMM_MULTIPLEXER_OPEN) { 2256 channel->state = RFCOMM_CHANNEL_W4_MULTIPLEXER; 2257 uint16_t l2cap_cid = 0; 2258 status = l2cap_create_channel(rfcomm_packet_handler, addr, BLUETOOTH_PROTOCOL_RFCOMM, l2cap_max_mtu(), &l2cap_cid); 2259 if (status) goto fail; 2260 multiplexer->l2cap_cid = l2cap_cid; 2261 return 0; 2262 } 2263 2264 channel->state = RFCOMM_CHANNEL_SEND_UIH_PN; 2265 2266 // start connecting, if multiplexer is already up and running 2267 l2cap_request_can_send_now_event(multiplexer->l2cap_cid); 2268 return 0; 2269 2270 fail: 2271 if (new_multiplexer) btstack_memory_rfcomm_multiplexer_free(multiplexer); 2272 if (channel) btstack_memory_rfcomm_channel_free(channel); 2273 return status; 2274 } 2275 2276 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){ 2277 return rfcomm_channel_create_internal(packet_handler, addr, server_channel, 1, initial_credits, out_rfcomm_cid); 2278 } 2279 2280 uint8_t rfcomm_create_channel(btstack_packet_handler_t packet_handler, bd_addr_t addr, uint8_t server_channel, uint16_t * out_rfcomm_cid){ 2281 return rfcomm_channel_create_internal(packet_handler, addr, server_channel, 0, RFCOMM_CREDITS, out_rfcomm_cid); 2282 } 2283 2284 void rfcomm_disconnect(uint16_t rfcomm_cid){ 2285 log_info("RFCOMM_DISCONNECT cid 0x%02x", rfcomm_cid); 2286 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2287 if (!channel) return; 2288 2289 channel->state = RFCOMM_CHANNEL_SEND_DISC; 2290 l2cap_request_can_send_now_event(channel->multiplexer->l2cap_cid); 2291 } 2292 2293 static uint8_t rfcomm_register_service_internal(btstack_packet_handler_t packet_handler, 2294 uint8_t channel, uint16_t max_frame_size, uint8_t incoming_flow_control, uint8_t initial_credits){ 2295 2296 log_info("RFCOMM_REGISTER_SERVICE channel #%u mtu %u flow_control %u credits %u", 2297 channel, max_frame_size, incoming_flow_control, initial_credits); 2298 2299 // check if already registered 2300 rfcomm_service_t * service = rfcomm_service_for_channel(channel); 2301 if (service){ 2302 return RFCOMM_CHANNEL_ALREADY_REGISTERED; 2303 } 2304 2305 // alloc structure 2306 service = btstack_memory_rfcomm_service_get(); 2307 if (!service) { 2308 return BTSTACK_MEMORY_ALLOC_FAILED; 2309 } 2310 2311 // register with l2cap if not registered before, max MTU 2312 if (btstack_linked_list_empty(&rfcomm_services)){ 2313 l2cap_register_service(rfcomm_packet_handler, BLUETOOTH_PROTOCOL_RFCOMM, 0xffff, rfcomm_security_level); 2314 } 2315 2316 // fill in 2317 service->packet_handler = packet_handler; 2318 service->server_channel = channel; 2319 service->max_frame_size = max_frame_size; 2320 service->incoming_flow_control = incoming_flow_control; 2321 service->incoming_initial_credits = initial_credits; 2322 2323 // add to services list 2324 btstack_linked_list_add(&rfcomm_services, (btstack_linked_item_t *) service); 2325 2326 return 0; 2327 } 2328 2329 uint8_t rfcomm_register_service_with_initial_credits(btstack_packet_handler_t packet_handler, 2330 uint8_t channel, uint16_t max_frame_size, uint8_t initial_credits){ 2331 2332 return rfcomm_register_service_internal(packet_handler, channel, max_frame_size, 1, initial_credits); 2333 } 2334 2335 uint8_t rfcomm_register_service(btstack_packet_handler_t packet_handler, uint8_t channel, 2336 uint16_t max_frame_size){ 2337 2338 return rfcomm_register_service_internal(packet_handler, channel, max_frame_size, 0,RFCOMM_CREDITS); 2339 } 2340 2341 void rfcomm_unregister_service(uint8_t service_channel){ 2342 log_info("RFCOMM_UNREGISTER_SERVICE #%u", service_channel); 2343 rfcomm_service_t *service = rfcomm_service_for_channel(service_channel); 2344 if (!service) return; 2345 btstack_linked_list_remove(&rfcomm_services, (btstack_linked_item_t *) service); 2346 btstack_memory_rfcomm_service_free(service); 2347 2348 // unregister if no services active 2349 if (btstack_linked_list_empty(&rfcomm_services)){ 2350 // bt_send_cmd(&l2cap_unregister_service, BLUETOOTH_PROTOCOL_RFCOMM); 2351 l2cap_unregister_service(BLUETOOTH_PROTOCOL_RFCOMM); 2352 } 2353 } 2354 2355 void rfcomm_accept_connection(uint16_t rfcomm_cid){ 2356 log_info("RFCOMM_ACCEPT_CONNECTION cid 0x%02x", rfcomm_cid); 2357 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2358 if (!channel) return; 2359 switch (channel->state) { 2360 case RFCOMM_CHANNEL_INCOMING_SETUP: 2361 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_CLIENT_ACCEPTED); 2362 if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_RCVD_PN){ 2363 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_PN_RSP); 2364 l2cap_request_can_send_now_event(channel->multiplexer->l2cap_cid); 2365 } 2366 if (channel->state_var & RFCOMM_CHANNEL_STATE_VAR_RCVD_SABM){ 2367 rfcomm_channel_state_add(channel, RFCOMM_CHANNEL_STATE_VAR_SEND_UA); 2368 l2cap_request_can_send_now_event(channel->multiplexer->l2cap_cid); 2369 } 2370 // at least one of { PN RSP, UA } needs to be sent 2371 // state transistion incoming setup -> dlc setup happens in rfcomm_run after these have been sent 2372 break; 2373 default: 2374 break; 2375 } 2376 2377 } 2378 2379 void rfcomm_decline_connection(uint16_t rfcomm_cid){ 2380 log_info("RFCOMM_DECLINE_CONNECTION cid 0x%02x", rfcomm_cid); 2381 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2382 if (!channel) return; 2383 switch (channel->state) { 2384 case RFCOMM_CHANNEL_INCOMING_SETUP: 2385 channel->state = RFCOMM_CHANNEL_SEND_DM; 2386 l2cap_request_can_send_now_event(channel->multiplexer->l2cap_cid); 2387 break; 2388 default: 2389 break; 2390 } 2391 } 2392 2393 void rfcomm_grant_credits(uint16_t rfcomm_cid, uint8_t credits){ 2394 log_info("RFCOMM_GRANT_CREDITS cid 0x%02x credits %u", rfcomm_cid, credits); 2395 rfcomm_channel_t * channel = rfcomm_channel_for_rfcomm_cid(rfcomm_cid); 2396 if (!channel) return; 2397 if (!channel->incoming_flow_control) return; 2398 channel->new_credits_incoming += credits; 2399 2400 // process 2401 l2cap_request_can_send_now_event(channel->multiplexer->l2cap_cid); 2402 } 2403 2404 2405