1 /* 2 * Copyright (C) 2009-2012 by Matthias Ringwald 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 MATTHIAS RINGWALD 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 [email protected] 34 * 35 */ 36 37 /* 38 * l2cap.c 39 * 40 * Logical Link Control and Adaption Protocl (L2CAP) 41 * 42 * Created by Matthias Ringwald on 5/16/09. 43 */ 44 45 #include "l2cap.h" 46 #include "hci.h" 47 #include "hci_dump.h" 48 #include "debug.h" 49 #include "btstack_memory.h" 50 51 #include <stdarg.h> 52 #include <string.h> 53 54 #include <stdio.h> 55 56 // nr of buffered acl packets in outgoing queue to get max performance 57 #define NR_BUFFERED_ACL_PACKETS 3 58 59 // used to cache l2cap rejects, echo, and informational requests 60 #define NR_PENDING_SIGNALING_RESPONSES 3 61 62 // offsets for L2CAP SIGNALING COMMANDS 63 #define L2CAP_SIGNALING_COMMAND_CODE_OFFSET 0 64 #define L2CAP_SIGNALING_COMMAND_SIGID_OFFSET 1 65 #define L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET 2 66 #define L2CAP_SIGNALING_COMMAND_DATA_OFFSET 4 67 68 static void null_packet_handler(void * connection, uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size); 69 static void l2cap_packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size); 70 71 // used to cache l2cap rejects, echo, and informational requests 72 static l2cap_signaling_response_t signaling_responses[NR_PENDING_SIGNALING_RESPONSES]; 73 static int signaling_responses_pending; 74 75 static linked_list_t l2cap_channels = NULL; 76 static linked_list_t l2cap_services = NULL; 77 static void (*packet_handler) (void * connection, uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size) = null_packet_handler; 78 static int new_credits_blocked = 0; 79 80 static btstack_packet_handler_t attribute_protocol_packet_handler = NULL; 81 static btstack_packet_handler_t security_protocol_packet_handler = NULL; 82 83 // prototypes 84 static void l2cap_finialize_channel_close(l2cap_channel_t *channel); 85 static l2cap_service_t * l2cap_get_service(uint16_t psm); 86 static void l2cap_emit_channel_opened(l2cap_channel_t *channel, uint8_t status); 87 static void l2cap_emit_channel_closed(l2cap_channel_t *channel); 88 static void l2cap_emit_connection_request(l2cap_channel_t *channel); 89 static int l2cap_channel_ready_for_open(l2cap_channel_t *channel); 90 91 92 void l2cap_init(){ 93 new_credits_blocked = 0; 94 signaling_responses_pending = 0; 95 96 l2cap_channels = NULL; 97 l2cap_services = NULL; 98 99 packet_handler = null_packet_handler; 100 101 // 102 // register callback with HCI 103 // 104 hci_register_packet_handler(&l2cap_packet_handler); 105 hci_connectable_control(0); // no services yet 106 } 107 108 109 /** Register L2CAP packet handlers */ 110 static void null_packet_handler(void * connection, uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 111 } 112 void l2cap_register_packet_handler(void (*handler)(void * connection, uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size)){ 113 packet_handler = handler; 114 } 115 116 // notify client/protocol handler 117 void l2cap_dispatch(l2cap_channel_t *channel, uint8_t type, uint8_t * data, uint16_t size){ 118 if (channel->packet_handler) { 119 (* (channel->packet_handler))(type, channel->local_cid, data, size); 120 } else { 121 (*packet_handler)(channel->connection, type, channel->local_cid, data, size); 122 } 123 } 124 125 void l2cap_emit_channel_opened(l2cap_channel_t *channel, uint8_t status) { 126 log_info("L2CAP_EVENT_CHANNEL_OPENED status 0x%x addr %s handle 0x%x psm 0x%x local_cid 0x%x remote_cid 0x%x local_mtu %u, remote_mtu %u", 127 status, bd_addr_to_str(channel->address), channel->handle, channel->psm, 128 channel->local_cid, channel->remote_cid, channel->local_mtu, channel->remote_mtu); 129 uint8_t event[21]; 130 event[0] = L2CAP_EVENT_CHANNEL_OPENED; 131 event[1] = sizeof(event) - 2; 132 event[2] = status; 133 bt_flip_addr(&event[3], channel->address); 134 bt_store_16(event, 9, channel->handle); 135 bt_store_16(event, 11, channel->psm); 136 bt_store_16(event, 13, channel->local_cid); 137 bt_store_16(event, 15, channel->remote_cid); 138 bt_store_16(event, 17, channel->local_mtu); 139 bt_store_16(event, 19, channel->remote_mtu); 140 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 141 l2cap_dispatch(channel, HCI_EVENT_PACKET, event, sizeof(event)); 142 } 143 144 void l2cap_emit_channel_closed(l2cap_channel_t *channel) { 145 log_info("L2CAP_EVENT_CHANNEL_CLOSED local_cid 0x%x", channel->local_cid); 146 uint8_t event[4]; 147 event[0] = L2CAP_EVENT_CHANNEL_CLOSED; 148 event[1] = sizeof(event) - 2; 149 bt_store_16(event, 2, channel->local_cid); 150 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 151 l2cap_dispatch(channel, HCI_EVENT_PACKET, event, sizeof(event)); 152 } 153 154 void l2cap_emit_connection_request(l2cap_channel_t *channel) { 155 log_info("L2CAP_EVENT_INCOMING_CONNECTION addr %s handle 0x%x psm 0x%x local_cid 0x%x remote_cid 0x%x", 156 bd_addr_to_str(channel->address), channel->handle, channel->psm, channel->local_cid, channel->remote_cid); 157 uint8_t event[16]; 158 event[0] = L2CAP_EVENT_INCOMING_CONNECTION; 159 event[1] = sizeof(event) - 2; 160 bt_flip_addr(&event[2], channel->address); 161 bt_store_16(event, 8, channel->handle); 162 bt_store_16(event, 10, channel->psm); 163 bt_store_16(event, 12, channel->local_cid); 164 bt_store_16(event, 14, channel->remote_cid); 165 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 166 l2cap_dispatch(channel, HCI_EVENT_PACKET, event, sizeof(event)); 167 } 168 169 static void l2cap_emit_service_registered(void *connection, uint8_t status, uint16_t psm){ 170 log_info("L2CAP_EVENT_SERVICE_REGISTERED status 0x%x psm 0x%x", status, psm); 171 uint8_t event[5]; 172 event[0] = L2CAP_EVENT_SERVICE_REGISTERED; 173 event[1] = sizeof(event) - 2; 174 event[2] = status; 175 bt_store_16(event, 3, psm); 176 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 177 (*packet_handler)(connection, HCI_EVENT_PACKET, 0, event, sizeof(event)); 178 } 179 180 void l2cap_emit_credits(l2cap_channel_t *channel, uint8_t credits) { 181 182 log_info("L2CAP_EVENT_CREDITS local_cid 0x%x credits %u", channel->local_cid, credits); 183 // track credits 184 channel->packets_granted += credits; 185 186 uint8_t event[5]; 187 event[0] = L2CAP_EVENT_CREDITS; 188 event[1] = sizeof(event) - 2; 189 bt_store_16(event, 2, channel->local_cid); 190 event[4] = credits; 191 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 192 l2cap_dispatch(channel, HCI_EVENT_PACKET, event, sizeof(event)); 193 } 194 195 void l2cap_block_new_credits(uint8_t blocked){ 196 new_credits_blocked = blocked; 197 } 198 199 void l2cap_hand_out_credits(void){ 200 201 if (new_credits_blocked) return; // we're told not to. used by daemon 202 203 linked_item_t *it; 204 for (it = (linked_item_t *) l2cap_channels; it ; it = it->next){ 205 if (!hci_number_free_acl_slots()) return; 206 l2cap_channel_t * channel = (l2cap_channel_t *) it; 207 if (channel->state != L2CAP_STATE_OPEN) continue; 208 if (hci_number_outgoing_packets(channel->handle) < NR_BUFFERED_ACL_PACKETS && channel->packets_granted == 0) { 209 l2cap_emit_credits(channel, 1); 210 } 211 } 212 } 213 214 l2cap_channel_t * l2cap_get_channel_for_local_cid(uint16_t local_cid){ 215 linked_item_t *it; 216 for (it = (linked_item_t *) l2cap_channels; it ; it = it->next){ 217 l2cap_channel_t * channel = (l2cap_channel_t *) it; 218 if ( channel->local_cid == local_cid) { 219 return channel; 220 } 221 } 222 return NULL; 223 } 224 225 int l2cap_can_send_packet_now(uint16_t local_cid){ 226 l2cap_channel_t *channel = l2cap_get_channel_for_local_cid(local_cid); 227 if (!channel) return 0; 228 if (!channel->packets_granted) return 0; 229 return hci_can_send_packet_now(HCI_ACL_DATA_PACKET); 230 } 231 232 uint16_t l2cap_get_remote_mtu_for_local_cid(uint16_t local_cid){ 233 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 234 if (channel) { 235 return channel->remote_mtu; 236 } 237 return 0; 238 } 239 240 int l2cap_send_signaling_packet(hci_con_handle_t handle, L2CAP_SIGNALING_COMMANDS cmd, uint8_t identifier, ...){ 241 242 if (!hci_can_send_packet_now(HCI_ACL_DATA_PACKET)){ 243 log_info("l2cap_send_signaling_packet, cannot send\n"); 244 return BTSTACK_ACL_BUFFERS_FULL; 245 } 246 247 // log_info("l2cap_send_signaling_packet type %u\n", cmd); 248 uint8_t *acl_buffer = hci_get_outgoing_acl_packet_buffer(); 249 va_list argptr; 250 va_start(argptr, identifier); 251 uint16_t len = l2cap_create_signaling_internal(acl_buffer, handle, cmd, identifier, argptr); 252 va_end(argptr); 253 // log_info("l2cap_send_signaling_packet con %u!\n", handle); 254 return hci_send_acl_packet(acl_buffer, len); 255 } 256 257 uint8_t *l2cap_get_outgoing_buffer(void){ 258 return hci_get_outgoing_acl_packet_buffer() + COMPLETE_L2CAP_HEADER; // 8 bytes 259 } 260 261 int l2cap_send_prepared(uint16_t local_cid, uint16_t len){ 262 263 if (!hci_can_send_packet_now(HCI_ACL_DATA_PACKET)){ 264 log_info("l2cap_send_internal cid 0x%02x, cannot send\n", local_cid); 265 return BTSTACK_ACL_BUFFERS_FULL; 266 } 267 268 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 269 if (!channel) { 270 log_error("l2cap_send_internal no channel for cid 0x%02x\n", local_cid); 271 return -1; // TODO: define error 272 } 273 274 if (channel->packets_granted == 0){ 275 log_error("l2cap_send_internal cid 0x%02x, no credits!\n", local_cid); 276 return -1; // TODO: define error 277 } 278 279 --channel->packets_granted; 280 281 log_debug("l2cap_send_internal cid 0x%02x, handle %u, 1 credit used, credits left %u;\n", 282 local_cid, channel->handle, channel->packets_granted); 283 284 uint8_t *acl_buffer = hci_get_outgoing_acl_packet_buffer(); 285 286 // 0 - Connection handle : PB=10 : BC=00 287 bt_store_16(acl_buffer, 0, channel->handle | (2 << 12) | (0 << 14)); 288 // 2 - ACL length 289 bt_store_16(acl_buffer, 2, len + 4); 290 // 4 - L2CAP packet length 291 bt_store_16(acl_buffer, 4, len + 0); 292 // 6 - L2CAP channel DEST 293 bt_store_16(acl_buffer, 6, channel->remote_cid); 294 // send 295 int err = hci_send_acl_packet(acl_buffer, len+8); 296 297 l2cap_hand_out_credits(); 298 299 return err; 300 } 301 302 int l2cap_send_prepared_connectionless(uint16_t handle, uint16_t cid, uint16_t len){ 303 304 if (!hci_can_send_packet_now(HCI_ACL_DATA_PACKET)){ 305 log_info("l2cap_send_prepared_to_handle cid 0x%02x, cannot send\n", cid); 306 return BTSTACK_ACL_BUFFERS_FULL; 307 } 308 309 log_debug("l2cap_send_prepared_to_handle cid 0x%02x, handle %u\n", cid, handle); 310 311 uint8_t *acl_buffer = hci_get_outgoing_acl_packet_buffer(); 312 313 // 0 - Connection handle : PB=10 : BC=00 314 bt_store_16(acl_buffer, 0, handle | (2 << 12) | (0 << 14)); 315 // 2 - ACL length 316 bt_store_16(acl_buffer, 2, len + 4); 317 // 4 - L2CAP packet length 318 bt_store_16(acl_buffer, 4, len + 0); 319 // 6 - L2CAP channel DEST 320 bt_store_16(acl_buffer, 6, cid); 321 // send 322 int err = hci_send_acl_packet(acl_buffer, len+8); 323 324 l2cap_hand_out_credits(); 325 326 return err; 327 } 328 329 int l2cap_send_internal(uint16_t local_cid, uint8_t *data, uint16_t len){ 330 331 if (!hci_can_send_packet_now(HCI_ACL_DATA_PACKET)){ 332 log_info("l2cap_send_internal cid 0x%02x, cannot send\n", local_cid); 333 return BTSTACK_ACL_BUFFERS_FULL; 334 } 335 336 uint8_t *acl_buffer = hci_get_outgoing_acl_packet_buffer(); 337 338 memcpy(&acl_buffer[8], data, len); 339 340 return l2cap_send_prepared(local_cid, len); 341 } 342 343 int l2cap_send_connectionless(uint16_t handle, uint16_t cid, uint8_t *data, uint16_t len){ 344 345 if (!hci_can_send_packet_now(HCI_ACL_DATA_PACKET)){ 346 log_info("l2cap_send_internal cid 0x%02x, cannot send\n", cid); 347 return BTSTACK_ACL_BUFFERS_FULL; 348 } 349 350 uint8_t *acl_buffer = hci_get_outgoing_acl_packet_buffer(); 351 352 memcpy(&acl_buffer[8], data, len); 353 354 return l2cap_send_prepared_connectionless(handle, cid, len); 355 } 356 357 static inline void channelStateVarSetFlag(l2cap_channel_t *channel, L2CAP_CHANNEL_STATE_VAR flag){ 358 channel->state_var = (L2CAP_CHANNEL_STATE_VAR) (channel->state_var | flag); 359 } 360 361 static inline void channelStateVarClearFlag(l2cap_channel_t *channel, L2CAP_CHANNEL_STATE_VAR flag){ 362 channel->state_var = (L2CAP_CHANNEL_STATE_VAR) (channel->state_var & ~flag); 363 } 364 365 366 367 // MARK: L2CAP_RUN 368 // process outstanding signaling tasks 369 void l2cap_run(void){ 370 371 // check pending signaling responses 372 while (signaling_responses_pending){ 373 374 if (!hci_can_send_packet_now(HCI_ACL_DATA_PACKET)) break; 375 376 hci_con_handle_t handle = signaling_responses[0].handle; 377 uint8_t sig_id = signaling_responses[0].sig_id; 378 uint16_t infoType = signaling_responses[0].data; // INFORMATION_REQUEST 379 uint16_t result = signaling_responses[0].data; // CONNECTION_REQUEST 380 381 switch (signaling_responses[0].code){ 382 case CONNECTION_REQUEST: 383 l2cap_send_signaling_packet(handle, CONNECTION_RESPONSE, sig_id, 0, 0, result, 0); 384 break; 385 case ECHO_REQUEST: 386 l2cap_send_signaling_packet(handle, ECHO_RESPONSE, sig_id, 0, NULL); 387 break; 388 case INFORMATION_REQUEST: 389 if (infoType == 2) { 390 uint32_t features = 0; 391 // extended features request supported, however no features present 392 l2cap_send_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, infoType, 0, 4, &features); 393 } else { 394 // all other types are not supported 395 l2cap_send_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, infoType, 1, 0, NULL); 396 } 397 break; 398 default: 399 // should not happen 400 break; 401 } 402 403 // remove first item 404 signaling_responses_pending--; 405 int i; 406 for (i=0; i < signaling_responses_pending; i++){ 407 memcpy(&signaling_responses[i], &signaling_responses[i+1], sizeof(l2cap_signaling_response_t)); 408 } 409 } 410 411 uint8_t config_options[4]; 412 linked_item_t *it; 413 linked_item_t *next; 414 for (it = (linked_item_t *) l2cap_channels; it ; it = next){ 415 next = it->next; // cache next item as current item might get freed 416 417 if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) break; 418 if (!hci_can_send_packet_now(HCI_ACL_DATA_PACKET)) break; 419 420 l2cap_channel_t * channel = (l2cap_channel_t *) it; 421 422 // log_info("l2cap_run: state %u, var 0x%02x\n", channel->state, channel->state_var); 423 424 425 switch (channel->state){ 426 427 case L2CAP_STATE_WILL_SEND_CREATE_CONNECTION: 428 // send connection request - set state first 429 channel->state = L2CAP_STATE_WAIT_CONNECTION_COMPLETE; 430 // BD_ADDR, Packet_Type, Page_Scan_Repetition_Mode, Reserved, Clock_Offset, Allow_Role_Switch 431 hci_send_cmd(&hci_create_connection, channel->address, hci_usable_acl_packet_types(), 0, 0, 0, 1); 432 break; 433 434 case L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE: 435 l2cap_send_signaling_packet(channel->handle, CONNECTION_RESPONSE, channel->remote_sig_id, 0, 0, channel->reason, 0); 436 // discard channel - l2cap_finialize_channel_close without sending l2cap close event 437 linked_list_remove(&l2cap_channels, (linked_item_t *) channel); // -- remove from list 438 btstack_memory_l2cap_channel_free(channel); 439 break; 440 441 case L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_ACCEPT: 442 channel->state = L2CAP_STATE_CONFIG; 443 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 444 l2cap_send_signaling_packet(channel->handle, CONNECTION_RESPONSE, channel->remote_sig_id, channel->local_cid, channel->remote_cid, 0, 0); 445 break; 446 447 case L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST: 448 // success, start l2cap handshake 449 channel->local_sig_id = l2cap_next_sig_id(); 450 channel->state = L2CAP_STATE_WAIT_CONNECT_RSP; 451 l2cap_send_signaling_packet( channel->handle, CONNECTION_REQUEST, channel->local_sig_id, channel->psm, channel->local_cid); 452 break; 453 454 case L2CAP_STATE_CONFIG: 455 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP){ 456 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP); 457 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SENT_CONF_RSP); 458 l2cap_send_signaling_packet(channel->handle, CONFIGURE_RESPONSE, channel->remote_sig_id, channel->remote_cid, 0, 0, 0, NULL); 459 } 460 else if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ){ 461 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 462 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SENT_CONF_REQ); 463 channel->local_sig_id = l2cap_next_sig_id(); 464 config_options[0] = 1; // MTU 465 config_options[1] = 2; // len param 466 bt_store_16( (uint8_t*)&config_options, 2, channel->local_mtu); 467 l2cap_send_signaling_packet(channel->handle, CONFIGURE_REQUEST, channel->local_sig_id, channel->remote_cid, 0, 4, &config_options); 468 } 469 if (l2cap_channel_ready_for_open(channel)){ 470 channel->state = L2CAP_STATE_OPEN; 471 l2cap_emit_channel_opened(channel, 0); // success 472 l2cap_emit_credits(channel, 1); 473 } 474 break; 475 476 case L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE: 477 l2cap_send_signaling_packet( channel->handle, DISCONNECTION_RESPONSE, channel->remote_sig_id, channel->local_cid, channel->remote_cid); 478 l2cap_finialize_channel_close(channel); // -- remove from list 479 break; 480 481 case L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST: 482 channel->local_sig_id = l2cap_next_sig_id(); 483 channel->state = L2CAP_STATE_WAIT_DISCONNECT; 484 l2cap_send_signaling_packet( channel->handle, DISCONNECTION_REQUEST, channel->local_sig_id, channel->remote_cid, channel->local_cid); 485 break; 486 default: 487 break; 488 } 489 } 490 } 491 492 uint16_t l2cap_max_mtu(void){ 493 return hci_max_acl_data_packet_length() - L2CAP_HEADER_SIZE; 494 } 495 496 // open outgoing L2CAP channel 497 void l2cap_create_channel_internal(void * connection, btstack_packet_handler_t packet_handler, 498 bd_addr_t address, uint16_t psm, uint16_t mtu){ 499 500 log_info("L2CAP_CREATE_CHANNEL_MTU addr %s psm 0x%x mtu %u", bd_addr_to_str(address), psm, mtu); 501 502 // alloc structure 503 l2cap_channel_t * chan = (l2cap_channel_t*) btstack_memory_l2cap_channel_get(); 504 if (!chan) { 505 // emit error event 506 l2cap_channel_t dummy_channel; 507 BD_ADDR_COPY(dummy_channel.address, address); 508 dummy_channel.psm = psm; 509 l2cap_emit_channel_opened(&dummy_channel, BTSTACK_MEMORY_ALLOC_FAILED); 510 return; 511 } 512 // limit local mtu to max acl packet length 513 if (mtu > l2cap_max_mtu()) { 514 mtu = l2cap_max_mtu(); 515 } 516 517 // fill in 518 BD_ADDR_COPY(chan->address, address); 519 chan->psm = psm; 520 chan->handle = 0; 521 chan->connection = connection; 522 chan->packet_handler = packet_handler; 523 chan->remote_mtu = L2CAP_MINIMAL_MTU; 524 chan->local_mtu = mtu; 525 chan->packets_granted = 0; 526 527 // set initial state 528 chan->state = L2CAP_STATE_WILL_SEND_CREATE_CONNECTION; 529 chan->state_var = L2CAP_CHANNEL_STATE_VAR_NONE; 530 chan->remote_sig_id = L2CAP_SIG_ID_INVALID; 531 chan->local_sig_id = L2CAP_SIG_ID_INVALID; 532 533 // add to connections list 534 linked_list_add(&l2cap_channels, (linked_item_t *) chan); 535 536 l2cap_run(); 537 } 538 539 void l2cap_disconnect_internal(uint16_t local_cid, uint8_t reason){ 540 log_info("L2CAP_DISCONNECT local_cid 0x%x reason 0x%x", local_cid, reason); 541 // find channel for local_cid 542 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 543 if (channel) { 544 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST; 545 } 546 // process 547 l2cap_run(); 548 } 549 550 static void l2cap_handle_connection_failed_for_addr(bd_addr_t address, uint8_t status){ 551 linked_item_t *it = (linked_item_t *) &l2cap_channels; 552 while (it->next){ 553 l2cap_channel_t * channel = (l2cap_channel_t *) it->next; 554 if ( ! BD_ADDR_CMP( channel->address, address) ){ 555 if (channel->state == L2CAP_STATE_WAIT_CONNECTION_COMPLETE || channel->state == L2CAP_STATE_WILL_SEND_CREATE_CONNECTION) { 556 // failure, forward error code 557 l2cap_emit_channel_opened(channel, status); 558 // discard channel 559 it->next = it->next->next; 560 btstack_memory_l2cap_channel_free(channel); 561 } 562 } else { 563 it = it->next; 564 } 565 } 566 } 567 568 static void l2cap_handle_connection_success_for_addr(bd_addr_t address, hci_con_handle_t handle){ 569 linked_item_t *it; 570 for (it = (linked_item_t *) l2cap_channels; it ; it = it->next){ 571 l2cap_channel_t * channel = (l2cap_channel_t *) it; 572 if ( ! BD_ADDR_CMP( channel->address, address) ){ 573 if (channel->state == L2CAP_STATE_WAIT_CONNECTION_COMPLETE || channel->state == L2CAP_STATE_WILL_SEND_CREATE_CONNECTION) { 574 // success, start l2cap handshake 575 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST; 576 channel->handle = handle; 577 channel->local_cid = l2cap_next_local_cid(); 578 } 579 } 580 } 581 // process 582 l2cap_run(); 583 } 584 585 void l2cap_event_handler( uint8_t *packet, uint16_t size ){ 586 587 bd_addr_t address; 588 hci_con_handle_t handle; 589 l2cap_channel_t * channel; 590 linked_item_t *it; 591 int hci_con_used; 592 593 switch(packet[0]){ 594 595 // handle connection complete events 596 case HCI_EVENT_CONNECTION_COMPLETE: 597 bt_flip_addr(address, &packet[5]); 598 if (packet[2] == 0){ 599 handle = READ_BT_16(packet, 3); 600 l2cap_handle_connection_success_for_addr(address, handle); 601 } else { 602 l2cap_handle_connection_failed_for_addr(address, packet[2]); 603 } 604 break; 605 606 // handle successful create connection cancel command 607 case HCI_EVENT_COMMAND_COMPLETE: 608 if ( COMMAND_COMPLETE_EVENT(packet, hci_create_connection_cancel) ) { 609 if (packet[5] == 0){ 610 bt_flip_addr(address, &packet[6]); 611 // CONNECTION TERMINATED BY LOCAL HOST (0X16) 612 l2cap_handle_connection_failed_for_addr(address, 0x16); 613 } 614 } 615 l2cap_run(); // try sending signaling packets first 616 break; 617 618 case HCI_EVENT_COMMAND_STATUS: 619 l2cap_run(); // try sending signaling packets first 620 break; 621 622 // handle disconnection complete events 623 case HCI_EVENT_DISCONNECTION_COMPLETE: 624 // send l2cap disconnect events for all channels on this handle 625 handle = READ_BT_16(packet, 3); 626 it = (linked_item_t *) &l2cap_channels; 627 while (it->next){ 628 l2cap_channel_t * channel = (l2cap_channel_t *) it->next; 629 if ( channel->handle == handle ){ 630 // update prev item before free'ing next element - don't call l2cap_finalize_channel_close 631 it->next = it->next->next; 632 l2cap_emit_channel_closed(channel); 633 btstack_memory_l2cap_channel_free(channel); 634 } else { 635 it = it->next; 636 } 637 } 638 break; 639 640 case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS: 641 l2cap_run(); // try sending signaling packets first 642 l2cap_hand_out_credits(); 643 break; 644 645 // HCI Connection Timeouts 646 case L2CAP_EVENT_TIMEOUT_CHECK: 647 handle = READ_BT_16(packet, 2); 648 if (hci_authentication_active_for_handle(handle)) break; 649 hci_con_used = 0; 650 for (it = (linked_item_t *) l2cap_channels; it ; it = it->next){ 651 channel = (l2cap_channel_t *) it; 652 if (channel->handle == handle) { 653 hci_con_used = 1; 654 } 655 } 656 if (hci_con_used) break; 657 if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) break; 658 hci_send_cmd(&hci_disconnect, handle, 0x13); // remote closed connection 659 break; 660 661 case DAEMON_EVENT_HCI_PACKET_SENT: 662 for (it = (linked_item_t *) l2cap_channels; it ; it = it->next){ 663 channel = (l2cap_channel_t *) it; 664 if (channel->packet_handler) { 665 (* (channel->packet_handler))(HCI_EVENT_PACKET, channel->local_cid, packet, size); 666 } 667 } 668 if (attribute_protocol_packet_handler) { 669 (*attribute_protocol_packet_handler)(HCI_EVENT_PACKET, 0, packet, size); 670 } 671 if (security_protocol_packet_handler) { 672 (*security_protocol_packet_handler)(HCI_EVENT_PACKET, 0, packet, size); 673 } 674 break; 675 676 default: 677 break; 678 } 679 680 // pass on 681 (*packet_handler)(NULL, HCI_EVENT_PACKET, 0, packet, size); 682 } 683 684 static void l2cap_handle_disconnect_request(l2cap_channel_t *channel, uint16_t identifier){ 685 channel->remote_sig_id = identifier; 686 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE; 687 l2cap_run(); 688 } 689 690 static void l2cap_register_signaling_response(hci_con_handle_t handle, uint8_t code, uint8_t sig_id, uint16_t data){ 691 // Vol 3, Part A, 4.3: "The DCID and SCID fields shall be ignored when the result field indi- cates the connection was refused." 692 if (signaling_responses_pending < NR_PENDING_SIGNALING_RESPONSES) { 693 signaling_responses[signaling_responses_pending].handle = handle; 694 signaling_responses[signaling_responses_pending].code = code; 695 signaling_responses[signaling_responses_pending].sig_id = sig_id; 696 signaling_responses[signaling_responses_pending].data = data; 697 signaling_responses_pending++; 698 l2cap_run(); 699 } 700 } 701 702 static void l2cap_handle_connection_request(hci_con_handle_t handle, uint8_t sig_id, uint16_t psm, uint16_t source_cid){ 703 704 // log_info("l2cap_handle_connection_request for handle %u, psm %u cid 0x%02x\n", handle, psm, source_cid); 705 l2cap_service_t *service = l2cap_get_service(psm); 706 if (!service) { 707 // 0x0002 PSM not supported 708 l2cap_register_signaling_response(handle, CONNECTION_REQUEST, sig_id, 0x0002); 709 return; 710 } 711 712 hci_connection_t * hci_connection = connection_for_handle( handle ); 713 if (!hci_connection) { 714 // 715 log_error("no hci_connection for handle %u\n", handle); 716 return; 717 } 718 // alloc structure 719 // log_info("l2cap_handle_connection_request register channel\n"); 720 l2cap_channel_t * channel = (l2cap_channel_t*) btstack_memory_l2cap_channel_get(); 721 if (!channel){ 722 // 0x0004 No resources available 723 l2cap_register_signaling_response(handle, CONNECTION_REQUEST, sig_id, 0x0004); 724 return; 725 } 726 727 // fill in 728 BD_ADDR_COPY(channel->address, hci_connection->address); 729 channel->psm = psm; 730 channel->handle = handle; 731 channel->connection = service->connection; 732 channel->packet_handler = service->packet_handler; 733 channel->local_cid = l2cap_next_local_cid(); 734 channel->remote_cid = source_cid; 735 channel->local_mtu = service->mtu; 736 channel->remote_mtu = L2CAP_DEFAULT_MTU; 737 channel->packets_granted = 0; 738 channel->remote_sig_id = sig_id; 739 740 // limit local mtu to max acl packet length 741 if (channel->local_mtu > l2cap_max_mtu()) { 742 channel->local_mtu = l2cap_max_mtu(); 743 } 744 745 // set initial state 746 channel->state = L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT; 747 channel->state_var = L2CAP_CHANNEL_STATE_VAR_NONE; 748 749 // add to connections list 750 linked_list_add(&l2cap_channels, (linked_item_t *) channel); 751 752 // emit incoming connection request 753 l2cap_emit_connection_request(channel); 754 } 755 756 void l2cap_accept_connection_internal(uint16_t local_cid){ 757 log_info("L2CAP_ACCEPT_CONNECTION local_cid 0x%x", local_cid); 758 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 759 if (!channel) { 760 log_error("l2cap_accept_connection_internal called but local_cid 0x%x not found", local_cid); 761 return; 762 } 763 764 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_ACCEPT; 765 766 // process 767 l2cap_run(); 768 } 769 770 void l2cap_decline_connection_internal(uint16_t local_cid, uint8_t reason){ 771 log_info("L2CAP_DECLINE_CONNECTION local_cid 0x%x, reason %x", local_cid, reason); 772 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid( local_cid); 773 if (!channel) { 774 log_error( "l2cap_decline_connection_internal called but local_cid 0x%x not found", local_cid); 775 return; 776 } 777 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE; 778 channel->reason = reason; 779 l2cap_run(); 780 } 781 782 void l2cap_signaling_handle_configure_request(l2cap_channel_t *channel, uint8_t *command){ 783 784 channel->remote_sig_id = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 785 786 // accept the other's configuration options 787 uint16_t end_pos = 4 + READ_BT_16(command, L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET); 788 uint16_t pos = 8; 789 while (pos < end_pos){ 790 uint8_t type = command[pos++]; 791 uint8_t length = command[pos++]; 792 // MTU { type(8): 1, len(8):2, MTU(16) } 793 if ((type & 0x7f) == 1 && length == 2){ 794 channel->remote_mtu = READ_BT_16(command, pos); 795 // log_info("l2cap cid 0x%02x, remote mtu %u\n", channel->local_cid, channel->remote_mtu); 796 } 797 pos += length; 798 } 799 } 800 801 static int l2cap_channel_ready_for_open(l2cap_channel_t *channel){ 802 // log_info("l2cap_channel_ready_for_open 0x%02x\n", channel->state_var); 803 if ((channel->state_var & L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_RSP) == 0) return 0; 804 if ((channel->state_var & L2CAP_CHANNEL_STATE_VAR_SENT_CONF_RSP) == 0) return 0; 805 return 1; 806 } 807 808 809 void l2cap_signaling_handler_channel(l2cap_channel_t *channel, uint8_t *command){ 810 811 uint8_t code = command[L2CAP_SIGNALING_COMMAND_CODE_OFFSET]; 812 uint8_t identifier = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 813 uint16_t result = 0; 814 815 log_info("L2CAP signaling handler code %u, state %u\n", code, channel->state); 816 817 // handle DISCONNECT REQUESTS seperately 818 if (code == DISCONNECTION_REQUEST){ 819 switch (channel->state){ 820 case L2CAP_STATE_CONFIG: 821 case L2CAP_STATE_OPEN: 822 case L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST: 823 case L2CAP_STATE_WAIT_DISCONNECT: 824 l2cap_handle_disconnect_request(channel, identifier); 825 break; 826 827 default: 828 // ignore in other states 829 break; 830 } 831 return; 832 } 833 834 // @STATEMACHINE(l2cap) 835 switch (channel->state) { 836 837 case L2CAP_STATE_WAIT_CONNECT_RSP: 838 switch (code){ 839 case CONNECTION_RESPONSE: 840 result = READ_BT_16 (command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+4); 841 switch (result) { 842 case 0: 843 // successful connection 844 channel->remote_cid = READ_BT_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 845 channel->state = L2CAP_STATE_CONFIG; 846 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 847 break; 848 case 1: 849 // connection pending. get some coffee 850 break; 851 default: 852 // channel closed 853 channel->state = L2CAP_STATE_CLOSED; 854 855 // map l2cap connection response result to BTstack status enumeration 856 l2cap_emit_channel_opened(channel, L2CAP_CONNECTION_RESPONSE_RESULT_SUCCESSFUL + result); 857 858 // drop link key if security block 859 if (L2CAP_CONNECTION_RESPONSE_RESULT_SUCCESSFUL + result == L2CAP_CONNECTION_RESPONSE_RESULT_REFUSED_SECURITY){ 860 hci_drop_link_key_for_bd_addr(&channel->address); 861 } 862 863 // discard channel 864 linked_list_remove(&l2cap_channels, (linked_item_t *) channel); 865 btstack_memory_l2cap_channel_free(channel); 866 break; 867 } 868 break; 869 870 default: 871 //@TODO: implement other signaling packets 872 break; 873 } 874 break; 875 876 case L2CAP_STATE_CONFIG: 877 switch (code) { 878 case CONFIGURE_REQUEST: 879 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_REQ); 880 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP); 881 l2cap_signaling_handle_configure_request(channel, command); 882 break; 883 case CONFIGURE_RESPONSE: 884 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_RSP); 885 break; 886 default: 887 break; 888 } 889 if (l2cap_channel_ready_for_open(channel)){ 890 // for open: 891 channel->state = L2CAP_STATE_OPEN; 892 l2cap_emit_channel_opened(channel, 0); 893 l2cap_emit_credits(channel, 1); 894 } 895 break; 896 897 case L2CAP_STATE_WAIT_DISCONNECT: 898 switch (code) { 899 case DISCONNECTION_RESPONSE: 900 l2cap_finialize_channel_close(channel); 901 break; 902 default: 903 //@TODO: implement other signaling packets 904 break; 905 } 906 break; 907 908 case L2CAP_STATE_CLOSED: 909 // @TODO handle incoming requests 910 break; 911 912 case L2CAP_STATE_OPEN: 913 //@TODO: implement other signaling packets, e.g. re-configure 914 break; 915 default: 916 break; 917 } 918 // log_info("new state %u\n", channel->state); 919 } 920 921 922 void l2cap_signaling_handler_dispatch( hci_con_handle_t handle, uint8_t * command){ 923 924 // get code, signalind identifier and command len 925 uint8_t code = command[L2CAP_SIGNALING_COMMAND_CODE_OFFSET]; 926 uint8_t sig_id = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 927 928 // not for a particular channel, and not CONNECTION_REQUEST, ECHO_[REQUEST|RESPONSE], INFORMATION_REQUEST 929 if (code < 1 || code == ECHO_RESPONSE || code > INFORMATION_REQUEST){ 930 return; 931 } 932 933 // general commands without an assigned channel 934 switch(code) { 935 936 case CONNECTION_REQUEST: { 937 uint16_t psm = READ_BT_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 938 uint16_t source_cid = READ_BT_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+2); 939 l2cap_handle_connection_request(handle, sig_id, psm, source_cid); 940 return; 941 } 942 943 case ECHO_REQUEST: 944 l2cap_register_signaling_response(handle, code, sig_id, 0); 945 return; 946 947 case INFORMATION_REQUEST: { 948 uint16_t infoType = READ_BT_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 949 l2cap_register_signaling_response(handle, code, sig_id, infoType); 950 return; 951 } 952 953 default: 954 break; 955 } 956 957 958 // Get potential destination CID 959 uint16_t dest_cid = READ_BT_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 960 961 // Find channel for this sig_id and connection handle 962 linked_item_t *it; 963 for (it = (linked_item_t *) l2cap_channels; it ; it = it->next){ 964 l2cap_channel_t * channel = (l2cap_channel_t *) it; 965 if (channel->handle == handle) { 966 if (code & 1) { 967 // match odd commands (responses) by previous signaling identifier 968 if (channel->local_sig_id == sig_id) { 969 l2cap_signaling_handler_channel(channel, command); 970 break; 971 } 972 } else { 973 // match even commands (requests) by local channel id 974 if (channel->local_cid == dest_cid) { 975 l2cap_signaling_handler_channel(channel, command); 976 break; 977 } 978 } 979 } 980 } 981 } 982 983 void l2cap_acl_handler( uint8_t *packet, uint16_t size ){ 984 985 // Get Channel ID 986 uint16_t channel_id = READ_L2CAP_CHANNEL_ID(packet); 987 hci_con_handle_t handle = READ_ACL_CONNECTION_HANDLE(packet); 988 989 switch (channel_id) { 990 991 case L2CAP_CID_SIGNALING: { 992 993 uint16_t command_offset = 8; 994 while (command_offset < size) { 995 996 // handle signaling commands 997 l2cap_signaling_handler_dispatch(handle, &packet[command_offset]); 998 999 // increment command_offset 1000 command_offset += L2CAP_SIGNALING_COMMAND_DATA_OFFSET + READ_BT_16(packet, command_offset + L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET); 1001 } 1002 break; 1003 } 1004 1005 case L2CAP_CID_ATTRIBUTE_PROTOCOL: 1006 if (attribute_protocol_packet_handler) { 1007 (*attribute_protocol_packet_handler)(ATT_DATA_PACKET, handle, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1008 } 1009 break; 1010 1011 case L2CAP_CID_SECURITY_MANAGER_PROTOCOL: 1012 if (security_protocol_packet_handler) { 1013 (*security_protocol_packet_handler)(SM_DATA_PACKET, handle, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1014 } 1015 break; 1016 1017 default: { 1018 // Find channel for this channel_id and connection handle 1019 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(channel_id); 1020 if (channel) { 1021 l2cap_dispatch(channel, L2CAP_DATA_PACKET, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1022 } 1023 break; 1024 } 1025 } 1026 1027 l2cap_run(); 1028 } 1029 1030 static void l2cap_packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){ 1031 switch (packet_type) { 1032 case HCI_EVENT_PACKET: 1033 l2cap_event_handler(packet, size); 1034 break; 1035 case HCI_ACL_DATA_PACKET: 1036 l2cap_acl_handler(packet, size); 1037 break; 1038 default: 1039 break; 1040 } 1041 } 1042 1043 // finalize closed channel - l2cap_handle_disconnect_request & DISCONNECTION_RESPONSE 1044 void l2cap_finialize_channel_close(l2cap_channel_t *channel){ 1045 channel->state = L2CAP_STATE_CLOSED; 1046 l2cap_emit_channel_closed(channel); 1047 // discard channel 1048 linked_list_remove(&l2cap_channels, (linked_item_t *) channel); 1049 btstack_memory_l2cap_channel_free(channel); 1050 } 1051 1052 l2cap_service_t * l2cap_get_service(uint16_t psm){ 1053 linked_item_t *it; 1054 1055 // close open channels 1056 for (it = (linked_item_t *) l2cap_services; it ; it = it->next){ 1057 l2cap_service_t * service = ((l2cap_service_t *) it); 1058 if ( service->psm == psm){ 1059 return service; 1060 }; 1061 } 1062 return NULL; 1063 } 1064 1065 void l2cap_register_service_internal(void *connection, btstack_packet_handler_t packet_handler, uint16_t psm, uint16_t mtu){ 1066 1067 log_info("L2CAP_REGISTER_SERVICE psm 0x%x mtu %u", psm, mtu); 1068 1069 // check for alread registered psm 1070 // TODO: emit error event 1071 l2cap_service_t *service = l2cap_get_service(psm); 1072 if (service) { 1073 log_error("l2cap_register_service_internal: PSM %u already registered\n", psm); 1074 l2cap_emit_service_registered(connection, L2CAP_SERVICE_ALREADY_REGISTERED, psm); 1075 return; 1076 } 1077 1078 // alloc structure 1079 // TODO: emit error event 1080 service = (l2cap_service_t *) btstack_memory_l2cap_service_get(); 1081 if (!service) { 1082 log_error("l2cap_register_service_internal: no memory for l2cap_service_t\n"); 1083 l2cap_emit_service_registered(connection, BTSTACK_MEMORY_ALLOC_FAILED, psm); 1084 return; 1085 } 1086 1087 // fill in 1088 service->psm = psm; 1089 service->mtu = mtu; 1090 service->connection = connection; 1091 service->packet_handler = packet_handler; 1092 1093 // add to services list 1094 linked_list_add(&l2cap_services, (linked_item_t *) service); 1095 1096 // enable page scan 1097 hci_connectable_control(1); 1098 1099 // done 1100 l2cap_emit_service_registered(connection, 0, psm); 1101 } 1102 1103 void l2cap_unregister_service_internal(void *connection, uint16_t psm){ 1104 1105 log_info("L2CAP_UNREGISTER_SERVICE psm 0x%x", psm); 1106 1107 l2cap_service_t *service = l2cap_get_service(psm); 1108 if (!service) return; 1109 linked_list_remove(&l2cap_services, (linked_item_t *) service); 1110 btstack_memory_l2cap_service_free(service); 1111 1112 // disable page scan when no services registered 1113 if (!linked_list_empty(&l2cap_services)) return; 1114 hci_connectable_control(0); 1115 } 1116 1117 // 1118 void l2cap_close_connection(void *connection){ 1119 linked_item_t *it; 1120 1121 // close open channels - note to myself: no channel is freed, so no new for fancy iterator tricks 1122 l2cap_channel_t * channel; 1123 for (it = (linked_item_t *) l2cap_channels; it ; it = it->next){ 1124 channel = (l2cap_channel_t *) it; 1125 if (channel->connection == connection) { 1126 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST; 1127 } 1128 } 1129 1130 // unregister services 1131 it = (linked_item_t *) &l2cap_services; 1132 while (it->next) { 1133 l2cap_service_t * service = (l2cap_service_t *) it->next; 1134 if (service->connection == connection){ 1135 it->next = it->next->next; 1136 btstack_memory_l2cap_service_free(service); 1137 } else { 1138 it = it->next; 1139 } 1140 } 1141 1142 // process 1143 l2cap_run(); 1144 } 1145 1146 // Bluetooth 4.0 - allows to register handler for Attribute Protocol and Security Manager Protocol 1147 void l2cap_register_fixed_channel(btstack_packet_handler_t packet_handler, uint16_t channel_id) { 1148 switch(channel_id){ 1149 case L2CAP_CID_ATTRIBUTE_PROTOCOL: 1150 attribute_protocol_packet_handler = packet_handler; 1151 break; 1152 case L2CAP_CID_SECURITY_MANAGER_PROTOCOL: 1153 security_protocol_packet_handler = packet_handler; 1154 break; 1155 } 1156 } 1157 1158