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 /* 39 * l2cap.c 40 * 41 * Logical Link Control and Adaption Protocl (L2CAP) 42 * 43 * Created by Matthias Ringwald on 5/16/09. 44 */ 45 46 #include "l2cap.h" 47 #include "hci.h" 48 #include "hci_dump.h" 49 #include "btstack_debug.h" 50 #include "btstack_memory.h" 51 52 #include <stdarg.h> 53 #include <string.h> 54 55 #include <stdio.h> 56 57 // nr of buffered acl packets in outgoing queue to get max performance 58 #define NR_BUFFERED_ACL_PACKETS 3 59 60 // used to cache l2cap rejects, echo, and informational requests 61 #define NR_PENDING_SIGNALING_RESPONSES 3 62 63 // offsets for L2CAP SIGNALING COMMANDS 64 #define L2CAP_SIGNALING_COMMAND_CODE_OFFSET 0 65 #define L2CAP_SIGNALING_COMMAND_SIGID_OFFSET 1 66 #define L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET 2 67 #define L2CAP_SIGNALING_COMMAND_DATA_OFFSET 4 68 69 static void null_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size); 70 static void l2cap_packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size); 71 72 // used to cache l2cap rejects, echo, and informational requests 73 static l2cap_signaling_response_t signaling_responses[NR_PENDING_SIGNALING_RESPONSES]; 74 static int signaling_responses_pending; 75 76 static btstack_packet_callback_registration_t hci_event_callback_registration; 77 78 static btstack_linked_list_t l2cap_channels; 79 static btstack_linked_list_t l2cap_services; 80 static btstack_linked_list_t l2cap_le_channels; 81 static btstack_linked_list_t l2cap_le_services; 82 static void (*packet_handler) (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size) = null_packet_handler; 83 84 static btstack_packet_handler_t attribute_protocol_packet_handler; 85 static btstack_packet_handler_t security_protocol_packet_handler; 86 static btstack_packet_handler_t connectionless_channel_packet_handler; 87 static uint8_t require_security_level2_for_outgoing_sdp; 88 89 // prototypes 90 static void l2cap_finialize_channel_close(l2cap_channel_t *channel); 91 static inline l2cap_service_t * l2cap_get_service(uint16_t psm); 92 static void l2cap_emit_channel_opened(l2cap_channel_t *channel, uint8_t status); 93 static void l2cap_emit_channel_closed(l2cap_channel_t *channel); 94 static void l2cap_emit_connection_request(l2cap_channel_t *channel); 95 static int l2cap_channel_ready_for_open(l2cap_channel_t *channel); 96 97 98 void l2cap_init(void){ 99 signaling_responses_pending = 0; 100 101 l2cap_channels = NULL; 102 l2cap_services = NULL; 103 l2cap_le_services = NULL; 104 l2cap_le_channels = NULL; 105 106 packet_handler = null_packet_handler; 107 attribute_protocol_packet_handler = NULL; 108 security_protocol_packet_handler = NULL; 109 connectionless_channel_packet_handler = NULL; 110 111 require_security_level2_for_outgoing_sdp = 0; 112 113 // 114 // register callback with HCI 115 // 116 hci_event_callback_registration.callback = &l2cap_packet_handler; 117 hci_add_event_handler(&hci_event_callback_registration); 118 119 hci_register_acl_packet_handler(&l2cap_packet_handler); 120 121 hci_connectable_control(0); // no services yet 122 } 123 124 125 /** Register L2CAP packet handlers */ 126 static void null_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 127 } 128 void l2cap_register_packet_handler(void (*handler)(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size)){ 129 packet_handler = handler; 130 } 131 132 // notify client/protocol handler 133 static void l2cap_dispatch(l2cap_channel_t *channel, uint8_t type, uint8_t * data, uint16_t size){ 134 if (channel->packet_handler) { 135 (* (channel->packet_handler))(type, channel->local_cid, data, size); 136 } else { 137 (*packet_handler)(type, channel->local_cid, data, size); 138 } 139 } 140 141 void l2cap_emit_channel_opened(l2cap_channel_t *channel, uint8_t status) { 142 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, flush_timeout %u", 143 status, bd_addr_to_str(channel->address), channel->handle, channel->psm, 144 channel->local_cid, channel->remote_cid, channel->local_mtu, channel->remote_mtu, channel->flush_timeout); 145 uint8_t event[23]; 146 event[0] = L2CAP_EVENT_CHANNEL_OPENED; 147 event[1] = sizeof(event) - 2; 148 event[2] = status; 149 bt_flip_addr(&event[3], channel->address); 150 little_endian_store_16(event, 9, channel->handle); 151 little_endian_store_16(event, 11, channel->psm); 152 little_endian_store_16(event, 13, channel->local_cid); 153 little_endian_store_16(event, 15, channel->remote_cid); 154 little_endian_store_16(event, 17, channel->local_mtu); 155 little_endian_store_16(event, 19, channel->remote_mtu); 156 little_endian_store_16(event, 21, channel->flush_timeout); 157 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 158 l2cap_dispatch(channel, HCI_EVENT_PACKET, event, sizeof(event)); 159 } 160 161 void l2cap_emit_channel_closed(l2cap_channel_t *channel) { 162 log_info("L2CAP_EVENT_CHANNEL_CLOSED local_cid 0x%x", channel->local_cid); 163 uint8_t event[4]; 164 event[0] = L2CAP_EVENT_CHANNEL_CLOSED; 165 event[1] = sizeof(event) - 2; 166 little_endian_store_16(event, 2, channel->local_cid); 167 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 168 l2cap_dispatch(channel, HCI_EVENT_PACKET, event, sizeof(event)); 169 } 170 171 void l2cap_emit_connection_request(l2cap_channel_t *channel) { 172 log_info("L2CAP_EVENT_INCOMING_CONNECTION addr %s handle 0x%x psm 0x%x local_cid 0x%x remote_cid 0x%x", 173 bd_addr_to_str(channel->address), channel->handle, channel->psm, channel->local_cid, channel->remote_cid); 174 uint8_t event[16]; 175 event[0] = L2CAP_EVENT_INCOMING_CONNECTION; 176 event[1] = sizeof(event) - 2; 177 bt_flip_addr(&event[2], channel->address); 178 little_endian_store_16(event, 8, channel->handle); 179 little_endian_store_16(event, 10, channel->psm); 180 little_endian_store_16(event, 12, channel->local_cid); 181 little_endian_store_16(event, 14, channel->remote_cid); 182 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 183 l2cap_dispatch(channel, HCI_EVENT_PACKET, event, sizeof(event)); 184 } 185 186 static void l2cap_emit_connection_parameter_update_response(uint16_t handle, uint16_t result){ 187 uint8_t event[6]; 188 event[0] = L2CAP_EVENT_CONNECTION_PARAMETER_UPDATE_RESPONSE; 189 event[1] = 4; 190 little_endian_store_16(event, 2, handle); 191 little_endian_store_16(event, 4, result); 192 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 193 (*packet_handler)(HCI_EVENT_PACKET, 0, event, sizeof(event)); 194 } 195 196 static l2cap_channel_t * l2cap_get_channel_for_local_cid(uint16_t local_cid){ 197 btstack_linked_list_iterator_t it; 198 btstack_linked_list_iterator_init(&it, &l2cap_channels); 199 while (btstack_linked_list_iterator_has_next(&it)){ 200 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 201 if ( channel->local_cid == local_cid) { 202 return channel; 203 } 204 } 205 return NULL; 206 } 207 208 int l2cap_can_send_packet_now(uint16_t local_cid){ 209 l2cap_channel_t *channel = l2cap_get_channel_for_local_cid(local_cid); 210 if (!channel) return 0; 211 return hci_can_send_acl_packet_now(channel->handle); 212 } 213 214 int l2cap_can_send_prepared_packet_now(uint16_t local_cid){ 215 l2cap_channel_t *channel = l2cap_get_channel_for_local_cid(local_cid); 216 if (!channel) return 0; 217 return hci_can_send_prepared_acl_packet_now(channel->handle); 218 } 219 220 int l2cap_can_send_fixed_channel_packet_now(uint16_t handle){ 221 return hci_can_send_acl_packet_now(handle); 222 } 223 224 uint16_t l2cap_get_remote_mtu_for_local_cid(uint16_t local_cid){ 225 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 226 if (channel) { 227 return channel->remote_mtu; 228 } 229 return 0; 230 } 231 232 static l2cap_channel_t * l2cap_channel_for_rtx_timer(btstack_timer_source_t * ts){ 233 btstack_linked_list_iterator_t it; 234 btstack_linked_list_iterator_init(&it, &l2cap_channels); 235 while (btstack_linked_list_iterator_has_next(&it)){ 236 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 237 if ( &channel->rtx == ts) { 238 return channel; 239 } 240 } 241 return NULL; 242 } 243 244 static void l2cap_rtx_timeout(btstack_timer_source_t * ts){ 245 l2cap_channel_t * channel = l2cap_channel_for_rtx_timer(ts); 246 if (!ts) return; 247 248 log_info("l2cap_rtx_timeout for local cid 0x%02x", channel->local_cid); 249 250 // "When terminating the channel, it is not necessary to send a L2CAP_DisconnectReq 251 // and enter WAIT_DISCONNECT state. Channels can be transitioned directly to the CLOSED state." 252 // notify client 253 l2cap_emit_channel_opened(channel, L2CAP_CONNECTION_RESPONSE_RESULT_RTX_TIMEOUT); 254 255 // discard channel 256 // no need to stop timer here, it is removed from list during timer callback 257 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 258 btstack_memory_l2cap_channel_free(channel); 259 } 260 261 static void l2cap_stop_rtx(l2cap_channel_t * channel){ 262 log_info("l2cap_stop_rtx for local cid 0x%02x", channel->local_cid); 263 btstack_run_loop_remove_timer(&channel->rtx); 264 } 265 266 static void l2cap_start_rtx(l2cap_channel_t * channel){ 267 l2cap_stop_rtx(channel); 268 log_info("l2cap_start_rtx for local cid 0x%02x", channel->local_cid); 269 btstack_run_loop_set_timer_handler(&channel->rtx, l2cap_rtx_timeout); 270 btstack_run_loop_set_timer(&channel->rtx, L2CAP_RTX_TIMEOUT_MS); 271 btstack_run_loop_add_timer(&channel->rtx); 272 } 273 274 static void l2cap_start_ertx(l2cap_channel_t * channel){ 275 log_info("l2cap_start_ertx for local cid 0x%02x", channel->local_cid); 276 l2cap_stop_rtx(channel); 277 btstack_run_loop_set_timer_handler(&channel->rtx, l2cap_rtx_timeout); 278 btstack_run_loop_set_timer(&channel->rtx, L2CAP_ERTX_TIMEOUT_MS); 279 btstack_run_loop_add_timer(&channel->rtx); 280 } 281 282 void l2cap_require_security_level_2_for_outgoing_sdp(void){ 283 require_security_level2_for_outgoing_sdp = 1; 284 } 285 286 static int l2cap_security_level_0_allowed_for_PSM(uint16_t psm){ 287 return (psm == PSM_SDP) && (!require_security_level2_for_outgoing_sdp); 288 } 289 290 static int l2cap_send_signaling_packet(hci_con_handle_t handle, L2CAP_SIGNALING_COMMANDS cmd, uint8_t identifier, ...){ 291 292 if (!hci_can_send_acl_packet_now(handle)){ 293 log_info("l2cap_send_signaling_packet, cannot send"); 294 return BTSTACK_ACL_BUFFERS_FULL; 295 } 296 297 // log_info("l2cap_send_signaling_packet type %u", cmd); 298 hci_reserve_packet_buffer(); 299 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 300 va_list argptr; 301 va_start(argptr, identifier); 302 uint16_t len = l2cap_create_signaling_classic(acl_buffer, handle, cmd, identifier, argptr); 303 va_end(argptr); 304 // log_info("l2cap_send_signaling_packet con %u!", handle); 305 return hci_send_acl_packet_buffer(len); 306 } 307 308 #ifdef ENABLE_BLE 309 static int l2cap_send_le_signaling_packet(hci_con_handle_t handle, L2CAP_SIGNALING_COMMANDS cmd, uint8_t identifier, ...){ 310 311 if (!hci_can_send_acl_packet_now(handle)){ 312 log_info("l2cap_send_signaling_packet, cannot send"); 313 return BTSTACK_ACL_BUFFERS_FULL; 314 } 315 316 // log_info("l2cap_send_signaling_packet type %u", cmd); 317 hci_reserve_packet_buffer(); 318 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 319 va_list argptr; 320 va_start(argptr, identifier); 321 uint16_t len = l2cap_create_signaling_le(acl_buffer, handle, cmd, identifier, argptr); 322 va_end(argptr); 323 // log_info("l2cap_send_signaling_packet con %u!", handle); 324 return hci_send_acl_packet_buffer(len); 325 } 326 #endif 327 328 uint8_t *l2cap_get_outgoing_buffer(void){ 329 return hci_get_outgoing_packet_buffer() + COMPLETE_L2CAP_HEADER; // 8 bytes 330 } 331 332 int l2cap_reserve_packet_buffer(void){ 333 return hci_reserve_packet_buffer(); 334 } 335 336 void l2cap_release_packet_buffer(void){ 337 hci_release_packet_buffer(); 338 } 339 340 341 int l2cap_send_prepared(uint16_t local_cid, uint16_t len){ 342 343 if (!hci_is_packet_buffer_reserved()){ 344 log_error("l2cap_send_prepared called without reserving packet first"); 345 return BTSTACK_ACL_BUFFERS_FULL; 346 } 347 348 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 349 if (!channel) { 350 log_error("l2cap_send_prepared no channel for cid 0x%02x", local_cid); 351 return -1; // TODO: define error 352 } 353 354 if (!hci_can_send_prepared_acl_packet_now(channel->handle)){ 355 log_info("l2cap_send_prepared cid 0x%02x, cannot send", local_cid); 356 return BTSTACK_ACL_BUFFERS_FULL; 357 } 358 359 log_debug("l2cap_send_prepared cid 0x%02x, handle %u, 1 credit used", local_cid, channel->handle); 360 361 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 362 363 int pb = hci_non_flushable_packet_boundary_flag_supported() ? 0x00 : 0x02; 364 365 // 0 - Connection handle : PB=pb : BC=00 366 little_endian_store_16(acl_buffer, 0, channel->handle | (pb << 12) | (0 << 14)); 367 // 2 - ACL length 368 little_endian_store_16(acl_buffer, 2, len + 4); 369 // 4 - L2CAP packet length 370 little_endian_store_16(acl_buffer, 4, len + 0); 371 // 6 - L2CAP channel DEST 372 little_endian_store_16(acl_buffer, 6, channel->remote_cid); 373 // send 374 int err = hci_send_acl_packet_buffer(len+8); 375 376 return err; 377 } 378 379 int l2cap_send_prepared_connectionless(uint16_t handle, uint16_t cid, uint16_t len){ 380 381 if (!hci_is_packet_buffer_reserved()){ 382 log_error("l2cap_send_prepared_connectionless called without reserving packet first"); 383 return BTSTACK_ACL_BUFFERS_FULL; 384 } 385 386 if (!hci_can_send_prepared_acl_packet_now(handle)){ 387 log_info("l2cap_send_prepared_connectionless handle 0x%02x, cid 0x%02x, cannot send", handle, cid); 388 return BTSTACK_ACL_BUFFERS_FULL; 389 } 390 391 log_debug("l2cap_send_prepared_connectionless handle %u, cid 0x%02x", handle, cid); 392 393 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 394 395 int pb = hci_non_flushable_packet_boundary_flag_supported() ? 0x00 : 0x02; 396 397 // 0 - Connection handle : PB=pb : BC=00 398 little_endian_store_16(acl_buffer, 0, handle | (pb << 12) | (0 << 14)); 399 // 2 - ACL length 400 little_endian_store_16(acl_buffer, 2, len + 4); 401 // 4 - L2CAP packet length 402 little_endian_store_16(acl_buffer, 4, len + 0); 403 // 6 - L2CAP channel DEST 404 little_endian_store_16(acl_buffer, 6, cid); 405 // send 406 int err = hci_send_acl_packet_buffer(len+8); 407 408 return err; 409 } 410 411 int l2cap_send(uint16_t local_cid, uint8_t *data, uint16_t len){ 412 413 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 414 if (!channel) { 415 log_error("l2cap_send no channel for cid 0x%02x", local_cid); 416 return -1; // TODO: define error 417 } 418 419 if (len > channel->remote_mtu){ 420 log_error("l2cap_send cid 0x%02x, data length exceeds remote MTU.", local_cid); 421 return L2CAP_DATA_LEN_EXCEEDS_REMOTE_MTU; 422 } 423 424 if (!hci_can_send_acl_packet_now(channel->handle)){ 425 log_info("l2cap_send cid 0x%02x, cannot send", local_cid); 426 return BTSTACK_ACL_BUFFERS_FULL; 427 } 428 429 hci_reserve_packet_buffer(); 430 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 431 432 memcpy(&acl_buffer[8], data, len); 433 434 return l2cap_send_prepared(local_cid, len); 435 } 436 437 int l2cap_send_connectionless(uint16_t handle, uint16_t cid, uint8_t *data, uint16_t len){ 438 439 if (!hci_can_send_acl_packet_now(handle)){ 440 log_info("l2cap_send cid 0x%02x, cannot send", cid); 441 return BTSTACK_ACL_BUFFERS_FULL; 442 } 443 444 hci_reserve_packet_buffer(); 445 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 446 447 memcpy(&acl_buffer[8], data, len); 448 449 return l2cap_send_prepared_connectionless(handle, cid, len); 450 } 451 452 int l2cap_send_echo_request(uint16_t handle, uint8_t *data, uint16_t len){ 453 return l2cap_send_signaling_packet(handle, ECHO_REQUEST, 0x77, len, data); 454 } 455 456 static inline void channelStateVarSetFlag(l2cap_channel_t *channel, L2CAP_CHANNEL_STATE_VAR flag){ 457 channel->state_var = (L2CAP_CHANNEL_STATE_VAR) (channel->state_var | flag); 458 } 459 460 static inline void channelStateVarClearFlag(l2cap_channel_t *channel, L2CAP_CHANNEL_STATE_VAR flag){ 461 channel->state_var = (L2CAP_CHANNEL_STATE_VAR) (channel->state_var & ~flag); 462 } 463 464 465 466 // MARK: L2CAP_RUN 467 // process outstanding signaling tasks 468 static void l2cap_run(void){ 469 470 // log_info("l2cap_run: entered"); 471 472 // check pending signaling responses 473 while (signaling_responses_pending){ 474 475 hci_con_handle_t handle = signaling_responses[0].handle; 476 477 if (!hci_can_send_acl_packet_now(handle)) break; 478 479 uint8_t sig_id = signaling_responses[0].sig_id; 480 uint16_t infoType = signaling_responses[0].data; // INFORMATION_REQUEST 481 uint16_t result = signaling_responses[0].data; // CONNECTION_REQUEST, COMMAND_REJECT 482 uint8_t response_code = signaling_responses[0].code; 483 484 // remove first item before sending (to avoid sending response mutliple times) 485 signaling_responses_pending--; 486 int i; 487 for (i=0; i < signaling_responses_pending; i++){ 488 memcpy(&signaling_responses[i], &signaling_responses[i+1], sizeof(l2cap_signaling_response_t)); 489 } 490 491 switch (response_code){ 492 case CONNECTION_REQUEST: 493 l2cap_send_signaling_packet(handle, CONNECTION_RESPONSE, sig_id, 0, 0, result, 0); 494 // also disconnect if result is 0x0003 - security blocked 495 if (result == 0x0003){ 496 hci_disconnect_security_block(handle); 497 } 498 break; 499 case ECHO_REQUEST: 500 l2cap_send_signaling_packet(handle, ECHO_RESPONSE, sig_id, 0, NULL); 501 break; 502 case INFORMATION_REQUEST: 503 switch (infoType){ 504 case 1: { // Connectionless MTU 505 uint16_t connectionless_mtu = hci_max_acl_data_packet_length(); 506 l2cap_send_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, infoType, 0, sizeof(connectionless_mtu), &connectionless_mtu); 507 break; 508 } 509 case 2: { // Extended Features Supported 510 // extended features request supported, features: fixed channels, unicast connectionless data reception 511 uint32_t features = 0x280; 512 l2cap_send_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, infoType, 0, sizeof(features), &features); 513 break; 514 } 515 case 3: { // Fixed Channels Supported 516 uint8_t map[8]; 517 memset(map, 0, 8); 518 map[0] = 0x01; // L2CAP Signaling Channel (0x01) + Connectionless reception (0x02) 519 l2cap_send_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, infoType, 0, sizeof(map), &map); 520 break; 521 } 522 default: 523 // all other types are not supported 524 l2cap_send_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, infoType, 1, 0, NULL); 525 break; 526 } 527 break; 528 case COMMAND_REJECT: 529 l2cap_send_signaling_packet(handle, COMMAND_REJECT, sig_id, result, 0, NULL); 530 #ifdef ENABLE_BLE 531 case COMMAND_REJECT_LE: 532 l2cap_send_le_signaling_packet(handle, COMMAND_REJECT, sig_id, result, 0, NULL); 533 break; 534 #endif 535 default: 536 // should not happen 537 break; 538 } 539 } 540 541 uint8_t config_options[4]; 542 btstack_linked_list_iterator_t it; 543 btstack_linked_list_iterator_init(&it, &l2cap_channels); 544 while (btstack_linked_list_iterator_has_next(&it)){ 545 546 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 547 // log_info("l2cap_run: channel %p, state %u, var 0x%02x", channel, channel->state, channel->state_var); 548 switch (channel->state){ 549 550 case L2CAP_STATE_WAIT_INCOMING_SECURITY_LEVEL_UPDATE: 551 case L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT: 552 if (!hci_can_send_acl_packet_now(channel->handle)) break; 553 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONN_RESP_PEND) { 554 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONN_RESP_PEND); 555 l2cap_send_signaling_packet(channel->handle, CONNECTION_RESPONSE, channel->remote_sig_id, channel->local_cid, channel->remote_cid, 1, 0); 556 } 557 break; 558 559 case L2CAP_STATE_WILL_SEND_CREATE_CONNECTION: 560 if (!hci_can_send_command_packet_now()) break; 561 // send connection request - set state first 562 channel->state = L2CAP_STATE_WAIT_CONNECTION_COMPLETE; 563 // BD_ADDR, Packet_Type, Page_Scan_Repetition_Mode, Reserved, Clock_Offset, Allow_Role_Switch 564 hci_send_cmd(&hci_create_connection, channel->address, hci_usable_acl_packet_types(), 0, 0, 0, 1); 565 break; 566 567 case L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE: 568 if (!hci_can_send_acl_packet_now(channel->handle)) break; 569 channel->state = L2CAP_STATE_INVALID; 570 l2cap_send_signaling_packet(channel->handle, CONNECTION_RESPONSE, channel->remote_sig_id, channel->local_cid, channel->remote_cid, channel->reason, 0); 571 // discard channel - l2cap_finialize_channel_close without sending l2cap close event 572 l2cap_stop_rtx(channel); 573 btstack_linked_list_iterator_remove(&it); 574 btstack_memory_l2cap_channel_free(channel); 575 break; 576 577 case L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_ACCEPT: 578 if (!hci_can_send_acl_packet_now(channel->handle)) break; 579 channel->state = L2CAP_STATE_CONFIG; 580 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 581 l2cap_send_signaling_packet(channel->handle, CONNECTION_RESPONSE, channel->remote_sig_id, channel->local_cid, channel->remote_cid, 0, 0); 582 break; 583 584 case L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST: 585 if (!hci_can_send_acl_packet_now(channel->handle)) break; 586 // success, start l2cap handshake 587 channel->local_sig_id = l2cap_next_sig_id(); 588 channel->state = L2CAP_STATE_WAIT_CONNECT_RSP; 589 l2cap_send_signaling_packet( channel->handle, CONNECTION_REQUEST, channel->local_sig_id, channel->psm, channel->local_cid); 590 l2cap_start_rtx(channel); 591 break; 592 593 case L2CAP_STATE_CONFIG: 594 if (!hci_can_send_acl_packet_now(channel->handle)) break; 595 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP){ 596 uint16_t flags = 0; 597 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP); 598 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT) { 599 flags = 1; 600 } else { 601 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SENT_CONF_RSP); 602 } 603 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_INVALID){ 604 l2cap_send_signaling_packet(channel->handle, CONFIGURE_RESPONSE, channel->remote_sig_id, channel->remote_cid, flags, L2CAP_CONF_RESULT_UNKNOWN_OPTIONS, 0, NULL); 605 } else if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU){ 606 config_options[0] = 1; // MTU 607 config_options[1] = 2; // len param 608 little_endian_store_16( (uint8_t*)&config_options, 2, channel->remote_mtu); 609 l2cap_send_signaling_packet(channel->handle, CONFIGURE_RESPONSE, channel->remote_sig_id, channel->remote_cid, flags, 0, 4, &config_options); 610 channelStateVarClearFlag(channel,L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU); 611 } else { 612 l2cap_send_signaling_packet(channel->handle, CONFIGURE_RESPONSE, channel->remote_sig_id, channel->remote_cid, flags, 0, 0, NULL); 613 } 614 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT); 615 } 616 else if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ){ 617 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 618 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SENT_CONF_REQ); 619 channel->local_sig_id = l2cap_next_sig_id(); 620 config_options[0] = 1; // MTU 621 config_options[1] = 2; // len param 622 little_endian_store_16( (uint8_t*)&config_options, 2, channel->local_mtu); 623 l2cap_send_signaling_packet(channel->handle, CONFIGURE_REQUEST, channel->local_sig_id, channel->remote_cid, 0, 4, &config_options); 624 l2cap_start_rtx(channel); 625 } 626 if (l2cap_channel_ready_for_open(channel)){ 627 channel->state = L2CAP_STATE_OPEN; 628 l2cap_emit_channel_opened(channel, 0); // success 629 } 630 break; 631 632 case L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE: 633 if (!hci_can_send_acl_packet_now(channel->handle)) break; 634 channel->state = L2CAP_STATE_INVALID; 635 l2cap_send_signaling_packet( channel->handle, DISCONNECTION_RESPONSE, channel->remote_sig_id, channel->local_cid, channel->remote_cid); 636 // we don't start an RTX timer for a disconnect - there's no point in closing the channel if the other side doesn't respond :) 637 l2cap_finialize_channel_close(channel); // -- remove from list 638 break; 639 640 case L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST: 641 if (!hci_can_send_acl_packet_now(channel->handle)) break; 642 channel->local_sig_id = l2cap_next_sig_id(); 643 channel->state = L2CAP_STATE_WAIT_DISCONNECT; 644 l2cap_send_signaling_packet( channel->handle, DISCONNECTION_REQUEST, channel->local_sig_id, channel->remote_cid, channel->local_cid); 645 break; 646 default: 647 break; 648 } 649 } 650 651 #ifdef ENABLE_BLE 652 // send l2cap con paramter update if necessary 653 hci_connections_get_iterator(&it); 654 while(btstack_linked_list_iterator_has_next(&it)){ 655 hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 656 if (connection->address_type != BD_ADDR_TYPE_LE_PUBLIC && connection->address_type != BD_ADDR_TYPE_LE_RANDOM) continue; 657 if (!hci_can_send_acl_packet_now(connection->con_handle)) continue; 658 switch (connection->le_con_parameter_update_state){ 659 case CON_PARAMETER_UPDATE_SEND_REQUEST: 660 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE; 661 l2cap_send_le_signaling_packet(connection->con_handle, CONNECTION_PARAMETER_UPDATE_REQUEST, connection->le_con_param_update_identifier, 662 connection->le_conn_interval_min, connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout); 663 break; 664 case CON_PARAMETER_UPDATE_SEND_RESPONSE: 665 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS; 666 l2cap_send_le_signaling_packet(connection->con_handle, CONNECTION_PARAMETER_UPDATE_RESPONSE, connection->le_con_param_update_identifier, 0); 667 break; 668 case CON_PARAMETER_UPDATE_DENY: 669 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE; 670 l2cap_send_le_signaling_packet(connection->con_handle, CONNECTION_PARAMETER_UPDATE_RESPONSE, connection->le_con_param_update_identifier, 1); 671 break; 672 default: 673 break; 674 } 675 } 676 #endif 677 678 // log_info("l2cap_run: exit"); 679 } 680 681 uint16_t l2cap_max_mtu(void){ 682 return HCI_ACL_PAYLOAD_SIZE - L2CAP_HEADER_SIZE; 683 } 684 685 uint16_t l2cap_max_le_mtu(void){ 686 return l2cap_max_mtu(); 687 } 688 689 static void l2cap_handle_connection_complete(uint16_t handle, l2cap_channel_t * channel){ 690 if (channel->state == L2CAP_STATE_WAIT_CONNECTION_COMPLETE || channel->state == L2CAP_STATE_WILL_SEND_CREATE_CONNECTION) { 691 log_info("l2cap_handle_connection_complete expected state"); 692 // success, start l2cap handshake 693 channel->handle = handle; 694 // check remote SSP feature first 695 channel->state = L2CAP_STATE_WAIT_REMOTE_SUPPORTED_FEATURES; 696 } 697 } 698 699 static void l2cap_handle_remote_supported_features_received(l2cap_channel_t * channel){ 700 if (channel->state != L2CAP_STATE_WAIT_REMOTE_SUPPORTED_FEATURES) return; 701 702 // we have been waiting for remote supported features, if both support SSP, 703 log_info("l2cap received remote supported features, sec_level_0_allowed for psm %u = %u", channel->psm, l2cap_security_level_0_allowed_for_PSM(channel->psm)); 704 if (hci_ssp_supported_on_both_sides(channel->handle) && !l2cap_security_level_0_allowed_for_PSM(channel->psm)){ 705 // request security level 2 706 channel->state = L2CAP_STATE_WAIT_OUTGOING_SECURITY_LEVEL_UPDATE; 707 gap_request_security_level(channel->handle, LEVEL_2); 708 return; 709 } 710 // fine, go ahead 711 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST; 712 } 713 714 /** 715 * @brief Creates L2CAP channel to the PSM of a remote device with baseband address. A new baseband connection will be initiated if necessary. 716 * @param packet_handler 717 * @param address 718 * @param psm 719 * @param mtu 720 * @param local_cid 721 */ 722 uint8_t l2cap_create_channel(btstack_packet_handler_t channel_packet_handler, bd_addr_t address, uint16_t psm, uint16_t mtu, uint16_t * out_local_cid){ 723 log_info("L2CAP_CREATE_CHANNEL addr %s psm 0x%x mtu %u", bd_addr_to_str(address), psm, mtu); 724 725 // alloc structure 726 l2cap_channel_t * chan = btstack_memory_l2cap_channel_get(); 727 if (!chan) { 728 return BTSTACK_MEMORY_ALLOC_FAILED; 729 } 730 731 // Init memory (make valgrind happy) 732 memset(chan, 0, sizeof(l2cap_channel_t)); 733 // limit local mtu to max acl packet length - l2cap header 734 if (mtu > l2cap_max_mtu()) { 735 mtu = l2cap_max_mtu(); 736 } 737 738 // fill in 739 BD_ADDR_COPY(chan->address, address); 740 chan->psm = psm; 741 chan->handle = 0; 742 chan->packet_handler = channel_packet_handler; 743 chan->remote_mtu = L2CAP_MINIMAL_MTU; 744 chan->local_mtu = mtu; 745 chan->local_cid = l2cap_next_local_cid(); 746 747 // set initial state 748 chan->state = L2CAP_STATE_WILL_SEND_CREATE_CONNECTION; 749 chan->state_var = L2CAP_CHANNEL_STATE_VAR_NONE; 750 chan->remote_sig_id = L2CAP_SIG_ID_INVALID; 751 chan->local_sig_id = L2CAP_SIG_ID_INVALID; 752 chan->required_security_level = LEVEL_0; 753 754 // add to connections list 755 btstack_linked_list_add(&l2cap_channels, (btstack_linked_item_t *) chan); 756 757 // store local_cid 758 if (out_local_cid){ 759 *out_local_cid = chan->local_cid; 760 } 761 762 // check if hci connection is already usable 763 hci_connection_t * conn = hci_connection_for_bd_addr_and_type(address, BD_ADDR_TYPE_CLASSIC); 764 if (conn){ 765 log_info("l2cap_create_channel, hci connection already exists"); 766 l2cap_handle_connection_complete(conn->con_handle, chan); 767 // check if remote supported fearures are already received 768 if (conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) { 769 l2cap_handle_remote_supported_features_received(chan); 770 } 771 } 772 773 l2cap_run(); 774 775 return 0; 776 } 777 778 void 779 l2cap_disconnect(uint16_t local_cid, uint8_t reason){ 780 log_info("L2CAP_DISCONNECT local_cid 0x%x reason 0x%x", local_cid, reason); 781 // find channel for local_cid 782 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 783 if (channel) { 784 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST; 785 } 786 // process 787 l2cap_run(); 788 } 789 790 static void l2cap_handle_connection_failed_for_addr(bd_addr_t address, uint8_t status){ 791 btstack_linked_list_iterator_t it; 792 btstack_linked_list_iterator_init(&it, &l2cap_channels); 793 while (btstack_linked_list_iterator_has_next(&it)){ 794 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 795 if ( BD_ADDR_CMP( channel->address, address) != 0) continue; 796 // channel for this address found 797 switch (channel->state){ 798 case L2CAP_STATE_WAIT_CONNECTION_COMPLETE: 799 case L2CAP_STATE_WILL_SEND_CREATE_CONNECTION: 800 // failure, forward error code 801 l2cap_emit_channel_opened(channel, status); 802 // discard channel 803 l2cap_stop_rtx(channel); 804 btstack_linked_list_iterator_remove(&it); 805 btstack_memory_l2cap_channel_free(channel); 806 break; 807 default: 808 break; 809 } 810 } 811 } 812 813 static void l2cap_handle_connection_success_for_addr(bd_addr_t address, hci_con_handle_t handle){ 814 btstack_linked_list_iterator_t it; 815 btstack_linked_list_iterator_init(&it, &l2cap_channels); 816 while (btstack_linked_list_iterator_has_next(&it)){ 817 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 818 if ( ! BD_ADDR_CMP( channel->address, address) ){ 819 l2cap_handle_connection_complete(handle, channel); 820 } 821 } 822 // process 823 l2cap_run(); 824 } 825 826 static void l2cap_event_handler(uint8_t *packet, uint16_t size){ 827 828 bd_addr_t address; 829 hci_con_handle_t handle; 830 btstack_linked_list_iterator_t it; 831 int hci_con_used; 832 833 switch(packet[0]){ 834 835 // handle connection complete events 836 case HCI_EVENT_CONNECTION_COMPLETE: 837 bt_flip_addr(address, &packet[5]); 838 if (packet[2] == 0){ 839 handle = little_endian_read_16(packet, 3); 840 l2cap_handle_connection_success_for_addr(address, handle); 841 } else { 842 l2cap_handle_connection_failed_for_addr(address, packet[2]); 843 } 844 break; 845 846 // handle successful create connection cancel command 847 case HCI_EVENT_COMMAND_COMPLETE: 848 if ( COMMAND_COMPLETE_EVENT(packet, hci_create_connection_cancel) ) { 849 if (packet[5] == 0){ 850 bt_flip_addr(address, &packet[6]); 851 // CONNECTION TERMINATED BY LOCAL HOST (0X16) 852 l2cap_handle_connection_failed_for_addr(address, 0x16); 853 } 854 } 855 l2cap_run(); // try sending signaling packets first 856 break; 857 858 case HCI_EVENT_COMMAND_STATUS: 859 l2cap_run(); // try sending signaling packets first 860 break; 861 862 // handle disconnection complete events 863 case HCI_EVENT_DISCONNECTION_COMPLETE: 864 // send l2cap disconnect events for all channels on this handle and free them 865 handle = little_endian_read_16(packet, 3); 866 btstack_linked_list_iterator_init(&it, &l2cap_channels); 867 while (btstack_linked_list_iterator_has_next(&it)){ 868 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 869 if (channel->handle != handle) continue; 870 l2cap_emit_channel_closed(channel); 871 l2cap_stop_rtx(channel); 872 btstack_linked_list_iterator_remove(&it); 873 btstack_memory_l2cap_channel_free(channel); 874 } 875 break; 876 877 case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS: 878 l2cap_run(); // try sending signaling packets first 879 break; 880 881 // HCI Connection Timeouts 882 case L2CAP_EVENT_TIMEOUT_CHECK: 883 handle = little_endian_read_16(packet, 2); 884 if (gap_get_connection_type(handle) != GAP_CONNECTION_ACL) break; 885 if (hci_authentication_active_for_handle(handle)) break; 886 hci_con_used = 0; 887 btstack_linked_list_iterator_init(&it, &l2cap_channels); 888 while (btstack_linked_list_iterator_has_next(&it)){ 889 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 890 if (channel->handle != handle) continue; 891 hci_con_used = 1; 892 break; 893 } 894 if (hci_con_used) break; 895 if (!hci_can_send_command_packet_now()) break; 896 hci_send_cmd(&hci_disconnect, handle, 0x13); // remote closed connection 897 break; 898 899 case DAEMON_EVENT_HCI_PACKET_SENT: 900 l2cap_run(); // try sending signaling packets first 901 902 btstack_linked_list_iterator_init(&it, &l2cap_channels); 903 while (btstack_linked_list_iterator_has_next(&it)){ 904 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 905 if (!channel->packet_handler) continue; 906 (* (channel->packet_handler))(HCI_EVENT_PACKET, channel->local_cid, packet, size); 907 } 908 if (attribute_protocol_packet_handler) { 909 (*attribute_protocol_packet_handler)(HCI_EVENT_PACKET, 0, packet, size); 910 } 911 if (connectionless_channel_packet_handler) { 912 (*connectionless_channel_packet_handler)(HCI_EVENT_PACKET, 0, packet, size); 913 } 914 break; 915 916 case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE: 917 handle = little_endian_read_16(packet, 3); 918 btstack_linked_list_iterator_init(&it, &l2cap_channels); 919 while (btstack_linked_list_iterator_has_next(&it)){ 920 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 921 if (channel->handle != handle) continue; 922 l2cap_handle_remote_supported_features_received(channel); 923 break; 924 } 925 break; 926 927 case GAP_EVENT_SECURITY_LEVEL: 928 handle = little_endian_read_16(packet, 2); 929 log_info("l2cap - security level update"); 930 btstack_linked_list_iterator_init(&it, &l2cap_channels); 931 while (btstack_linked_list_iterator_has_next(&it)){ 932 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 933 if (channel->handle != handle) continue; 934 935 log_info("l2cap - state %u", channel->state); 936 937 gap_security_level_t actual_level = (gap_security_level_t) packet[4]; 938 gap_security_level_t required_level = channel->required_security_level; 939 940 switch (channel->state){ 941 case L2CAP_STATE_WAIT_INCOMING_SECURITY_LEVEL_UPDATE: 942 if (actual_level >= required_level){ 943 channel->state = L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT; 944 l2cap_emit_connection_request(channel); 945 } else { 946 channel->reason = 0x0003; // security block 947 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE; 948 } 949 break; 950 951 case L2CAP_STATE_WAIT_OUTGOING_SECURITY_LEVEL_UPDATE: 952 if (actual_level >= required_level){ 953 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST; 954 } else { 955 // disconnnect, authentication not good enough 956 hci_disconnect_security_block(handle); 957 } 958 break; 959 960 default: 961 break; 962 } 963 } 964 break; 965 966 default: 967 break; 968 } 969 970 // pass on: main packet handler, att and sm packet handlers 971 (*packet_handler)(HCI_EVENT_PACKET, 0, packet, size); 972 if (attribute_protocol_packet_handler){ 973 (*attribute_protocol_packet_handler)(HCI_EVENT_PACKET, 0, packet, size); 974 } 975 if (connectionless_channel_packet_handler) { 976 (*connectionless_channel_packet_handler)(HCI_EVENT_PACKET, 0, packet, size); 977 } 978 979 l2cap_run(); 980 } 981 982 static void l2cap_handle_disconnect_request(l2cap_channel_t *channel, uint16_t identifier){ 983 channel->remote_sig_id = identifier; 984 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE; 985 l2cap_run(); 986 } 987 988 static void l2cap_register_signaling_response(hci_con_handle_t handle, uint8_t code, uint8_t sig_id, uint16_t data){ 989 // Vol 3, Part A, 4.3: "The DCID and SCID fields shall be ignored when the result field indi- cates the connection was refused." 990 if (signaling_responses_pending < NR_PENDING_SIGNALING_RESPONSES) { 991 signaling_responses[signaling_responses_pending].handle = handle; 992 signaling_responses[signaling_responses_pending].code = code; 993 signaling_responses[signaling_responses_pending].sig_id = sig_id; 994 signaling_responses[signaling_responses_pending].data = data; 995 signaling_responses_pending++; 996 l2cap_run(); 997 } 998 } 999 1000 static void l2cap_handle_connection_request(hci_con_handle_t handle, uint8_t sig_id, uint16_t psm, uint16_t source_cid){ 1001 1002 // log_info("l2cap_handle_connection_request for handle %u, psm %u cid 0x%02x", handle, psm, source_cid); 1003 l2cap_service_t *service = l2cap_get_service(psm); 1004 if (!service) { 1005 // 0x0002 PSM not supported 1006 l2cap_register_signaling_response(handle, CONNECTION_REQUEST, sig_id, 0x0002); 1007 return; 1008 } 1009 1010 hci_connection_t * hci_connection = hci_connection_for_handle( handle ); 1011 if (!hci_connection) { 1012 // 1013 log_error("no hci_connection for handle %u", handle); 1014 return; 1015 } 1016 1017 // alloc structure 1018 // log_info("l2cap_handle_connection_request register channel"); 1019 l2cap_channel_t * channel = btstack_memory_l2cap_channel_get(); 1020 if (!channel){ 1021 // 0x0004 No resources available 1022 l2cap_register_signaling_response(handle, CONNECTION_REQUEST, sig_id, 0x0004); 1023 return; 1024 } 1025 // Init memory (make valgrind happy) 1026 memset(channel, 0, sizeof(l2cap_channel_t)); 1027 // fill in 1028 BD_ADDR_COPY(channel->address, hci_connection->address); 1029 channel->psm = psm; 1030 channel->handle = handle; 1031 channel->packet_handler = service->packet_handler; 1032 channel->local_cid = l2cap_next_local_cid(); 1033 channel->remote_cid = source_cid; 1034 channel->local_mtu = service->mtu; 1035 channel->remote_mtu = L2CAP_DEFAULT_MTU; 1036 channel->remote_sig_id = sig_id; 1037 channel->required_security_level = service->required_security_level; 1038 1039 // limit local mtu to max acl packet length - l2cap header 1040 if (channel->local_mtu > l2cap_max_mtu()) { 1041 channel->local_mtu = l2cap_max_mtu(); 1042 } 1043 1044 // set initial state 1045 channel->state = L2CAP_STATE_WAIT_INCOMING_SECURITY_LEVEL_UPDATE; 1046 channel->state_var = L2CAP_CHANNEL_STATE_VAR_SEND_CONN_RESP_PEND; 1047 1048 // add to connections list 1049 btstack_linked_list_add(&l2cap_channels, (btstack_linked_item_t *) channel); 1050 1051 // assert security requirements 1052 gap_request_security_level(handle, channel->required_security_level); 1053 } 1054 1055 void l2cap_accept_connection(uint16_t local_cid){ 1056 log_info("L2CAP_ACCEPT_CONNECTION local_cid 0x%x", local_cid); 1057 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 1058 if (!channel) { 1059 log_error("l2cap_accept_connection called but local_cid 0x%x not found", local_cid); 1060 return; 1061 } 1062 1063 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_ACCEPT; 1064 1065 // process 1066 l2cap_run(); 1067 } 1068 1069 void l2cap_decline_connection(uint16_t local_cid, uint8_t reason){ 1070 log_info("L2CAP_DECLINE_CONNECTION local_cid 0x%x, reason %x", local_cid, reason); 1071 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid( local_cid); 1072 if (!channel) { 1073 log_error( "l2cap_decline_connection called but local_cid 0x%x not found", local_cid); 1074 return; 1075 } 1076 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE; 1077 channel->reason = reason; 1078 l2cap_run(); 1079 } 1080 1081 static void l2cap_signaling_handle_configure_request(l2cap_channel_t *channel, uint8_t *command){ 1082 1083 channel->remote_sig_id = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 1084 1085 uint16_t flags = little_endian_read_16(command, 6); 1086 if (flags & 1) { 1087 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT); 1088 } 1089 1090 // accept the other's configuration options 1091 uint16_t end_pos = 4 + little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET); 1092 uint16_t pos = 8; 1093 while (pos < end_pos){ 1094 uint8_t option_hint = command[pos] >> 7; 1095 uint8_t option_type = command[pos] & 0x7f; 1096 log_info("l2cap cid %u, hint %u, type %u", channel->local_cid, option_hint, option_type); 1097 pos++; 1098 uint8_t length = command[pos++]; 1099 // MTU { type(8): 1, len(8):2, MTU(16) } 1100 if (option_type == 1 && length == 2){ 1101 channel->remote_mtu = little_endian_read_16(command, pos); 1102 // log_info("l2cap cid 0x%02x, remote mtu %u", channel->local_cid, channel->remote_mtu); 1103 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU); 1104 } 1105 // Flush timeout { type(8):2, len(8): 2, Flush Timeout(16)} 1106 if (option_type == 2 && length == 2){ 1107 channel->flush_timeout = little_endian_read_16(command, pos); 1108 } 1109 // check for unknown options 1110 if (option_hint == 0 && (option_type == 0 || option_type >= 0x07)){ 1111 log_info("l2cap cid %u, unknown options", channel->local_cid); 1112 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_INVALID); 1113 } 1114 pos += length; 1115 } 1116 } 1117 1118 static int l2cap_channel_ready_for_open(l2cap_channel_t *channel){ 1119 // log_info("l2cap_channel_ready_for_open 0x%02x", channel->state_var); 1120 if ((channel->state_var & L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_RSP) == 0) return 0; 1121 if ((channel->state_var & L2CAP_CHANNEL_STATE_VAR_SENT_CONF_RSP) == 0) return 0; 1122 // addition check that fixes re-entrance issue causing l2cap event channel opened twice 1123 if (channel->state == L2CAP_STATE_OPEN) return 0; 1124 return 1; 1125 } 1126 1127 1128 static void l2cap_signaling_handler_channel(l2cap_channel_t *channel, uint8_t *command){ 1129 1130 uint8_t code = command[L2CAP_SIGNALING_COMMAND_CODE_OFFSET]; 1131 uint8_t identifier = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 1132 uint16_t result = 0; 1133 1134 log_info("L2CAP signaling handler code %u, state %u", code, channel->state); 1135 1136 // handle DISCONNECT REQUESTS seperately 1137 if (code == DISCONNECTION_REQUEST){ 1138 switch (channel->state){ 1139 case L2CAP_STATE_CONFIG: 1140 case L2CAP_STATE_OPEN: 1141 case L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST: 1142 case L2CAP_STATE_WAIT_DISCONNECT: 1143 l2cap_handle_disconnect_request(channel, identifier); 1144 break; 1145 1146 default: 1147 // ignore in other states 1148 break; 1149 } 1150 return; 1151 } 1152 1153 // @STATEMACHINE(l2cap) 1154 switch (channel->state) { 1155 1156 case L2CAP_STATE_WAIT_CONNECT_RSP: 1157 switch (code){ 1158 case CONNECTION_RESPONSE: 1159 l2cap_stop_rtx(channel); 1160 result = little_endian_read_16 (command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+4); 1161 switch (result) { 1162 case 0: 1163 // successful connection 1164 channel->remote_cid = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 1165 channel->state = L2CAP_STATE_CONFIG; 1166 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 1167 break; 1168 case 1: 1169 // connection pending. get some coffee, but start the ERTX 1170 l2cap_start_ertx(channel); 1171 break; 1172 default: 1173 // channel closed 1174 channel->state = L2CAP_STATE_CLOSED; 1175 // map l2cap connection response result to BTstack status enumeration 1176 l2cap_emit_channel_opened(channel, L2CAP_CONNECTION_RESPONSE_RESULT_SUCCESSFUL + result); 1177 1178 // drop link key if security block 1179 if (L2CAP_CONNECTION_RESPONSE_RESULT_SUCCESSFUL + result == L2CAP_CONNECTION_RESPONSE_RESULT_REFUSED_SECURITY){ 1180 hci_drop_link_key_for_bd_addr(channel->address); 1181 } 1182 1183 // discard channel 1184 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 1185 btstack_memory_l2cap_channel_free(channel); 1186 break; 1187 } 1188 break; 1189 1190 default: 1191 //@TODO: implement other signaling packets 1192 break; 1193 } 1194 break; 1195 1196 case L2CAP_STATE_CONFIG: 1197 result = little_endian_read_16 (command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+4); 1198 switch (code) { 1199 case CONFIGURE_REQUEST: 1200 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP); 1201 l2cap_signaling_handle_configure_request(channel, command); 1202 if (!(channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT)){ 1203 // only done if continuation not set 1204 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_REQ); 1205 } 1206 break; 1207 case CONFIGURE_RESPONSE: 1208 l2cap_stop_rtx(channel); 1209 switch (result){ 1210 case 0: // success 1211 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_RSP); 1212 break; 1213 case 4: // pending 1214 l2cap_start_ertx(channel); 1215 break; 1216 default: 1217 // retry on negative result 1218 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 1219 break; 1220 } 1221 break; 1222 default: 1223 break; 1224 } 1225 if (l2cap_channel_ready_for_open(channel)){ 1226 // for open: 1227 channel->state = L2CAP_STATE_OPEN; 1228 l2cap_emit_channel_opened(channel, 0); 1229 } 1230 break; 1231 1232 case L2CAP_STATE_WAIT_DISCONNECT: 1233 switch (code) { 1234 case DISCONNECTION_RESPONSE: 1235 l2cap_finialize_channel_close(channel); 1236 break; 1237 default: 1238 //@TODO: implement other signaling packets 1239 break; 1240 } 1241 break; 1242 1243 case L2CAP_STATE_CLOSED: 1244 // @TODO handle incoming requests 1245 break; 1246 1247 case L2CAP_STATE_OPEN: 1248 //@TODO: implement other signaling packets, e.g. re-configure 1249 break; 1250 default: 1251 break; 1252 } 1253 // log_info("new state %u", channel->state); 1254 } 1255 1256 1257 static void l2cap_signaling_handler_dispatch( hci_con_handle_t handle, uint8_t * command){ 1258 1259 // get code, signalind identifier and command len 1260 uint8_t code = command[L2CAP_SIGNALING_COMMAND_CODE_OFFSET]; 1261 uint8_t sig_id = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 1262 1263 // not for a particular channel, and not CONNECTION_REQUEST, ECHO_[REQUEST|RESPONSE], INFORMATION_REQUEST 1264 if (code < 1 || code == ECHO_RESPONSE || code > INFORMATION_REQUEST){ 1265 l2cap_register_signaling_response(handle, COMMAND_REJECT, sig_id, L2CAP_REJ_CMD_UNKNOWN); 1266 return; 1267 } 1268 1269 // general commands without an assigned channel 1270 switch(code) { 1271 1272 case CONNECTION_REQUEST: { 1273 uint16_t psm = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 1274 uint16_t source_cid = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+2); 1275 l2cap_handle_connection_request(handle, sig_id, psm, source_cid); 1276 return; 1277 } 1278 1279 case ECHO_REQUEST: 1280 l2cap_register_signaling_response(handle, code, sig_id, 0); 1281 return; 1282 1283 case INFORMATION_REQUEST: { 1284 uint16_t infoType = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 1285 l2cap_register_signaling_response(handle, code, sig_id, infoType); 1286 return; 1287 } 1288 1289 default: 1290 break; 1291 } 1292 1293 1294 // Get potential destination CID 1295 uint16_t dest_cid = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 1296 1297 // Find channel for this sig_id and connection handle 1298 btstack_linked_list_iterator_t it; 1299 btstack_linked_list_iterator_init(&it, &l2cap_channels); 1300 while (btstack_linked_list_iterator_has_next(&it)){ 1301 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 1302 if (channel->handle != handle) continue; 1303 if (code & 1) { 1304 // match odd commands (responses) by previous signaling identifier 1305 if (channel->local_sig_id == sig_id) { 1306 l2cap_signaling_handler_channel(channel, command); 1307 break; 1308 } 1309 } else { 1310 // match even commands (requests) by local channel id 1311 if (channel->local_cid == dest_cid) { 1312 l2cap_signaling_handler_channel(channel, command); 1313 break; 1314 } 1315 } 1316 } 1317 } 1318 1319 static void l2cap_acl_handler( uint8_t *packet, uint16_t size ){ 1320 1321 // Get Channel ID 1322 uint16_t channel_id = READ_L2CAP_CHANNEL_ID(packet); 1323 hci_con_handle_t handle = READ_ACL_CONNECTION_HANDLE(packet); 1324 1325 switch (channel_id) { 1326 1327 case L2CAP_CID_SIGNALING: { 1328 1329 uint16_t command_offset = 8; 1330 while (command_offset < size) { 1331 1332 // handle signaling commands 1333 l2cap_signaling_handler_dispatch(handle, &packet[command_offset]); 1334 1335 // increment command_offset 1336 command_offset += L2CAP_SIGNALING_COMMAND_DATA_OFFSET + little_endian_read_16(packet, command_offset + L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET); 1337 } 1338 break; 1339 } 1340 1341 case L2CAP_CID_ATTRIBUTE_PROTOCOL: 1342 if (attribute_protocol_packet_handler) { 1343 (*attribute_protocol_packet_handler)(ATT_DATA_PACKET, handle, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1344 } 1345 break; 1346 1347 case L2CAP_CID_SECURITY_MANAGER_PROTOCOL: 1348 if (security_protocol_packet_handler) { 1349 (*security_protocol_packet_handler)(SM_DATA_PACKET, handle, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1350 } 1351 break; 1352 1353 case L2CAP_CID_CONNECTIONLESS_CHANNEL: 1354 if (connectionless_channel_packet_handler) { 1355 (*connectionless_channel_packet_handler)(UCD_DATA_PACKET, handle, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1356 } 1357 break; 1358 1359 case L2CAP_CID_SIGNALING_LE: { 1360 switch (packet[8]){ 1361 case CONNECTION_PARAMETER_UPDATE_RESPONSE: { 1362 uint16_t result = little_endian_read_16(packet, 12); 1363 l2cap_emit_connection_parameter_update_response(handle, result); 1364 break; 1365 } 1366 case CONNECTION_PARAMETER_UPDATE_REQUEST: { 1367 uint8_t event[10]; 1368 event[0] = L2CAP_EVENT_CONNECTION_PARAMETER_UPDATE_REQUEST; 1369 event[1] = 8; 1370 memcpy(&event[2], &packet[12], 8); 1371 1372 hci_connection_t * connection = hci_connection_for_handle(handle); 1373 if (connection){ 1374 if (connection->role != HCI_ROLE_MASTER){ 1375 // reject command without notifying upper layer when not in master role 1376 uint8_t sig_id = packet[COMPLETE_L2CAP_HEADER + 1]; 1377 l2cap_register_signaling_response(handle, COMMAND_REJECT_LE, sig_id, L2CAP_REJ_CMD_UNKNOWN); 1378 break; 1379 } 1380 int update_parameter = 1; 1381 le_connection_parameter_range_t existing_range; 1382 gap_le_get_connection_parameter_range(existing_range); 1383 uint16_t le_conn_interval_min = little_endian_read_16(packet,12); 1384 uint16_t le_conn_interval_max = little_endian_read_16(packet,14); 1385 uint16_t le_conn_latency = little_endian_read_16(packet,16); 1386 uint16_t le_supervision_timeout = little_endian_read_16(packet,18); 1387 1388 if (le_conn_interval_min < existing_range.le_conn_interval_min) update_parameter = 0; 1389 if (le_conn_interval_max > existing_range.le_conn_interval_max) update_parameter = 0; 1390 1391 if (le_conn_latency < existing_range.le_conn_latency_min) update_parameter = 0; 1392 if (le_conn_latency > existing_range.le_conn_latency_max) update_parameter = 0; 1393 1394 if (le_supervision_timeout < existing_range.le_supervision_timeout_min) update_parameter = 0; 1395 if (le_supervision_timeout > existing_range.le_supervision_timeout_max) update_parameter = 0; 1396 1397 if (update_parameter){ 1398 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_RESPONSE; 1399 connection->le_conn_interval_min = le_conn_interval_min; 1400 connection->le_conn_interval_max = le_conn_interval_max; 1401 connection->le_conn_latency = le_conn_latency; 1402 connection->le_supervision_timeout = le_supervision_timeout; 1403 } else { 1404 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_DENY; 1405 } 1406 connection->le_con_param_update_identifier = packet[COMPLETE_L2CAP_HEADER + 1]; 1407 } 1408 1409 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 1410 (*packet_handler)( HCI_EVENT_PACKET, 0, event, sizeof(event)); 1411 1412 break; 1413 } 1414 default: { 1415 uint8_t sig_id = packet[COMPLETE_L2CAP_HEADER + 1]; 1416 l2cap_register_signaling_response(handle, COMMAND_REJECT_LE, sig_id, L2CAP_REJ_CMD_UNKNOWN); 1417 break; 1418 } 1419 } 1420 break; 1421 } 1422 1423 default: { 1424 // Find channel for this channel_id and connection handle 1425 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(channel_id); 1426 if (channel) { 1427 l2cap_dispatch(channel, L2CAP_DATA_PACKET, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1428 } 1429 break; 1430 } 1431 } 1432 } 1433 1434 static void l2cap_packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){ 1435 switch (packet_type) { 1436 case HCI_EVENT_PACKET: 1437 l2cap_event_handler(packet, size); 1438 break; 1439 case HCI_ACL_DATA_PACKET: 1440 l2cap_acl_handler(packet, size); 1441 break; 1442 default: 1443 break; 1444 } 1445 l2cap_run(); 1446 } 1447 1448 // finalize closed channel - l2cap_handle_disconnect_request & DISCONNECTION_RESPONSE 1449 void l2cap_finialize_channel_close(l2cap_channel_t *channel){ 1450 channel->state = L2CAP_STATE_CLOSED; 1451 l2cap_emit_channel_closed(channel); 1452 // discard channel 1453 l2cap_stop_rtx(channel); 1454 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 1455 btstack_memory_l2cap_channel_free(channel); 1456 } 1457 1458 static l2cap_service_t * l2cap_get_service_internal(btstack_linked_list_t * services, uint16_t psm){ 1459 btstack_linked_list_iterator_t it; 1460 btstack_linked_list_iterator_init(&it, services); 1461 while (btstack_linked_list_iterator_has_next(&it)){ 1462 l2cap_service_t * service = (l2cap_service_t *) btstack_linked_list_iterator_next(&it); 1463 if ( service->psm == psm){ 1464 return service; 1465 }; 1466 } 1467 return NULL; 1468 } 1469 1470 static inline l2cap_service_t * l2cap_get_service(uint16_t psm){ 1471 return l2cap_get_service_internal(&l2cap_services, psm); 1472 } 1473 1474 1475 uint8_t l2cap_register_service(btstack_packet_handler_t service_packet_handler, uint16_t psm, uint16_t mtu, gap_security_level_t security_level){ 1476 1477 log_info("L2CAP_REGISTER_SERVICE psm 0x%x mtu %u", psm, mtu); 1478 1479 // check for alread registered psm 1480 // TODO: emit error event 1481 l2cap_service_t *service = l2cap_get_service(psm); 1482 if (service) { 1483 log_error("l2cap_register_service: PSM %u already registered", psm); 1484 return L2CAP_SERVICE_ALREADY_REGISTERED; 1485 } 1486 1487 // alloc structure 1488 // TODO: emit error event 1489 service = btstack_memory_l2cap_service_get(); 1490 if (!service) { 1491 log_error("l2cap_register_service: no memory for l2cap_service_t"); 1492 return BTSTACK_MEMORY_ALLOC_FAILED; 1493 } 1494 1495 // fill in 1496 service->psm = psm; 1497 service->mtu = mtu; 1498 service->packet_handler = service_packet_handler; 1499 service->required_security_level = security_level; 1500 1501 // add to services list 1502 btstack_linked_list_add(&l2cap_services, (btstack_linked_item_t *) service); 1503 1504 // enable page scan 1505 hci_connectable_control(1); 1506 1507 return 0; 1508 } 1509 1510 void l2cap_unregister_service(uint16_t psm){ 1511 1512 log_info("L2CAP_UNREGISTER_SERVICE psm 0x%x", psm); 1513 1514 l2cap_service_t *service = l2cap_get_service(psm); 1515 if (!service) return; 1516 btstack_linked_list_remove(&l2cap_services, (btstack_linked_item_t *) service); 1517 btstack_memory_l2cap_service_free(service); 1518 1519 // disable page scan when no services registered 1520 if (!btstack_linked_list_empty(&l2cap_services)) return; 1521 hci_connectable_control(0); 1522 } 1523 1524 // Bluetooth 4.0 - allows to register handler for Attribute Protocol and Security Manager Protocol 1525 void l2cap_register_fixed_channel(btstack_packet_handler_t the_packet_handler, uint16_t channel_id) { 1526 switch(channel_id){ 1527 case L2CAP_CID_ATTRIBUTE_PROTOCOL: 1528 attribute_protocol_packet_handler = the_packet_handler; 1529 break; 1530 case L2CAP_CID_SECURITY_MANAGER_PROTOCOL: 1531 security_protocol_packet_handler = the_packet_handler; 1532 break; 1533 case L2CAP_CID_CONNECTIONLESS_CHANNEL: 1534 connectionless_channel_packet_handler = the_packet_handler; 1535 break; 1536 } 1537 } 1538 1539 #ifdef ENABLE_BLE 1540 1541 1542 #if 0 1543 static inline l2cap_service_t * l2cap_le_get_service(uint16_t psm){ 1544 return l2cap_get_service_internal(&l2cap_le_services, psm); 1545 } 1546 /** 1547 * @brief Regster L2CAP LE Credit Based Flow Control Mode service 1548 * @param 1549 */ 1550 void l2cap_le_register_service(btstack_packet_handler_t packet_handler, uint16_t psm, 1551 uint16_t mtu, uint16_t mps, uint16_t initial_credits, gap_security_level_t security_level){ 1552 1553 log_info("L2CAP_LE_REGISTER_SERVICE psm 0x%x mtu %u connection %p", psm, mtu, connection); 1554 1555 // check for alread registered psm 1556 // TODO: emit error event 1557 l2cap_service_t *service = l2cap_le_get_service(psm); 1558 if (service) { 1559 log_error("l2cap_le_register_service_internal: PSM %u already registered", psm); 1560 l2cap_emit_service_registered(connection, L2CAP_SERVICE_ALREADY_REGISTERED, psm); 1561 return; 1562 } 1563 1564 // alloc structure 1565 // TODO: emit error event 1566 service = btstack_memory_l2cap_service_get(); 1567 if (!service) { 1568 log_error("l2cap_register_service_internal: no memory for l2cap_service_t"); 1569 l2cap_emit_service_registered(connection, BTSTACK_MEMORY_ALLOC_FAILED, psm); 1570 return; 1571 } 1572 1573 // fill in 1574 service->psm = psm; 1575 service->mtu = mtu; 1576 service->mps = mps; 1577 service->packet_handler = packet_handler; 1578 service->required_security_level = security_level; 1579 1580 // add to services list 1581 btstack_linked_list_add(&l2cap_le_services, (btstack_linked_item_t *) service); 1582 1583 // done 1584 l2cap_emit_service_registered(connection, 0, psm); 1585 } 1586 1587 void l2cap_le_unregister_service(uint16_t psm) { 1588 1589 log_info("L2CAP_LE_UNREGISTER_SERVICE psm 0x%x", psm); 1590 1591 l2cap_service_t *service = l2cap_le_get_service(psm); 1592 if (!service) return; 1593 btstack_linked_list_remove(&l2cap_le_services, (btstack_linked_item_t *) service); 1594 btstack_memory_l2cap_service_free(service); 1595 } 1596 #endif 1597 #endif 1598