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 (security_protocol_packet_handler) { 912 (*security_protocol_packet_handler)(HCI_EVENT_PACKET, 0, packet, size); 913 } 914 if (connectionless_channel_packet_handler) { 915 (*connectionless_channel_packet_handler)(HCI_EVENT_PACKET, 0, packet, size); 916 } 917 break; 918 919 case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE: 920 handle = little_endian_read_16(packet, 3); 921 btstack_linked_list_iterator_init(&it, &l2cap_channels); 922 while (btstack_linked_list_iterator_has_next(&it)){ 923 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 924 if (channel->handle != handle) continue; 925 l2cap_handle_remote_supported_features_received(channel); 926 break; 927 } 928 break; 929 930 case GAP_EVENT_SECURITY_LEVEL: 931 handle = little_endian_read_16(packet, 2); 932 log_info("l2cap - security level update"); 933 btstack_linked_list_iterator_init(&it, &l2cap_channels); 934 while (btstack_linked_list_iterator_has_next(&it)){ 935 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 936 if (channel->handle != handle) continue; 937 938 log_info("l2cap - state %u", channel->state); 939 940 gap_security_level_t actual_level = (gap_security_level_t) packet[4]; 941 gap_security_level_t required_level = channel->required_security_level; 942 943 switch (channel->state){ 944 case L2CAP_STATE_WAIT_INCOMING_SECURITY_LEVEL_UPDATE: 945 if (actual_level >= required_level){ 946 channel->state = L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT; 947 l2cap_emit_connection_request(channel); 948 } else { 949 channel->reason = 0x0003; // security block 950 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE; 951 } 952 break; 953 954 case L2CAP_STATE_WAIT_OUTGOING_SECURITY_LEVEL_UPDATE: 955 if (actual_level >= required_level){ 956 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST; 957 } else { 958 // disconnnect, authentication not good enough 959 hci_disconnect_security_block(handle); 960 } 961 break; 962 963 default: 964 break; 965 } 966 } 967 break; 968 969 default: 970 break; 971 } 972 973 // pass on: main packet handler, att and sm packet handlers 974 (*packet_handler)(HCI_EVENT_PACKET, 0, packet, size); 975 if (attribute_protocol_packet_handler){ 976 (*attribute_protocol_packet_handler)(HCI_EVENT_PACKET, 0, packet, size); 977 } 978 if (security_protocol_packet_handler) { 979 (*security_protocol_packet_handler)(HCI_EVENT_PACKET, 0, packet, size); 980 } 981 if (connectionless_channel_packet_handler) { 982 (*connectionless_channel_packet_handler)(HCI_EVENT_PACKET, 0, packet, size); 983 } 984 985 l2cap_run(); 986 } 987 988 static void l2cap_handle_disconnect_request(l2cap_channel_t *channel, uint16_t identifier){ 989 channel->remote_sig_id = identifier; 990 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE; 991 l2cap_run(); 992 } 993 994 static void l2cap_register_signaling_response(hci_con_handle_t handle, uint8_t code, uint8_t sig_id, uint16_t data){ 995 // Vol 3, Part A, 4.3: "The DCID and SCID fields shall be ignored when the result field indi- cates the connection was refused." 996 if (signaling_responses_pending < NR_PENDING_SIGNALING_RESPONSES) { 997 signaling_responses[signaling_responses_pending].handle = handle; 998 signaling_responses[signaling_responses_pending].code = code; 999 signaling_responses[signaling_responses_pending].sig_id = sig_id; 1000 signaling_responses[signaling_responses_pending].data = data; 1001 signaling_responses_pending++; 1002 l2cap_run(); 1003 } 1004 } 1005 1006 static void l2cap_handle_connection_request(hci_con_handle_t handle, uint8_t sig_id, uint16_t psm, uint16_t source_cid){ 1007 1008 // log_info("l2cap_handle_connection_request for handle %u, psm %u cid 0x%02x", handle, psm, source_cid); 1009 l2cap_service_t *service = l2cap_get_service(psm); 1010 if (!service) { 1011 // 0x0002 PSM not supported 1012 l2cap_register_signaling_response(handle, CONNECTION_REQUEST, sig_id, 0x0002); 1013 return; 1014 } 1015 1016 hci_connection_t * hci_connection = hci_connection_for_handle( handle ); 1017 if (!hci_connection) { 1018 // 1019 log_error("no hci_connection for handle %u", handle); 1020 return; 1021 } 1022 1023 // alloc structure 1024 // log_info("l2cap_handle_connection_request register channel"); 1025 l2cap_channel_t * channel = btstack_memory_l2cap_channel_get(); 1026 if (!channel){ 1027 // 0x0004 No resources available 1028 l2cap_register_signaling_response(handle, CONNECTION_REQUEST, sig_id, 0x0004); 1029 return; 1030 } 1031 // Init memory (make valgrind happy) 1032 memset(channel, 0, sizeof(l2cap_channel_t)); 1033 // fill in 1034 BD_ADDR_COPY(channel->address, hci_connection->address); 1035 channel->psm = psm; 1036 channel->handle = handle; 1037 channel->packet_handler = service->packet_handler; 1038 channel->local_cid = l2cap_next_local_cid(); 1039 channel->remote_cid = source_cid; 1040 channel->local_mtu = service->mtu; 1041 channel->remote_mtu = L2CAP_DEFAULT_MTU; 1042 channel->remote_sig_id = sig_id; 1043 channel->required_security_level = service->required_security_level; 1044 1045 // limit local mtu to max acl packet length - l2cap header 1046 if (channel->local_mtu > l2cap_max_mtu()) { 1047 channel->local_mtu = l2cap_max_mtu(); 1048 } 1049 1050 // set initial state 1051 channel->state = L2CAP_STATE_WAIT_INCOMING_SECURITY_LEVEL_UPDATE; 1052 channel->state_var = L2CAP_CHANNEL_STATE_VAR_SEND_CONN_RESP_PEND; 1053 1054 // add to connections list 1055 btstack_linked_list_add(&l2cap_channels, (btstack_linked_item_t *) channel); 1056 1057 // assert security requirements 1058 gap_request_security_level(handle, channel->required_security_level); 1059 } 1060 1061 void l2cap_accept_connection(uint16_t local_cid){ 1062 log_info("L2CAP_ACCEPT_CONNECTION local_cid 0x%x", local_cid); 1063 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 1064 if (!channel) { 1065 log_error("l2cap_accept_connection called but local_cid 0x%x not found", local_cid); 1066 return; 1067 } 1068 1069 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_ACCEPT; 1070 1071 // process 1072 l2cap_run(); 1073 } 1074 1075 void l2cap_decline_connection(uint16_t local_cid, uint8_t reason){ 1076 log_info("L2CAP_DECLINE_CONNECTION local_cid 0x%x, reason %x", local_cid, reason); 1077 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid( local_cid); 1078 if (!channel) { 1079 log_error( "l2cap_decline_connection called but local_cid 0x%x not found", local_cid); 1080 return; 1081 } 1082 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE; 1083 channel->reason = reason; 1084 l2cap_run(); 1085 } 1086 1087 static void l2cap_signaling_handle_configure_request(l2cap_channel_t *channel, uint8_t *command){ 1088 1089 channel->remote_sig_id = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 1090 1091 uint16_t flags = little_endian_read_16(command, 6); 1092 if (flags & 1) { 1093 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT); 1094 } 1095 1096 // accept the other's configuration options 1097 uint16_t end_pos = 4 + little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET); 1098 uint16_t pos = 8; 1099 while (pos < end_pos){ 1100 uint8_t option_hint = command[pos] >> 7; 1101 uint8_t option_type = command[pos] & 0x7f; 1102 log_info("l2cap cid %u, hint %u, type %u", channel->local_cid, option_hint, option_type); 1103 pos++; 1104 uint8_t length = command[pos++]; 1105 // MTU { type(8): 1, len(8):2, MTU(16) } 1106 if (option_type == 1 && length == 2){ 1107 channel->remote_mtu = little_endian_read_16(command, pos); 1108 // log_info("l2cap cid 0x%02x, remote mtu %u", channel->local_cid, channel->remote_mtu); 1109 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU); 1110 } 1111 // Flush timeout { type(8):2, len(8): 2, Flush Timeout(16)} 1112 if (option_type == 2 && length == 2){ 1113 channel->flush_timeout = little_endian_read_16(command, pos); 1114 } 1115 // check for unknown options 1116 if (option_hint == 0 && (option_type == 0 || option_type >= 0x07)){ 1117 log_info("l2cap cid %u, unknown options", channel->local_cid); 1118 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_INVALID); 1119 } 1120 pos += length; 1121 } 1122 } 1123 1124 static int l2cap_channel_ready_for_open(l2cap_channel_t *channel){ 1125 // log_info("l2cap_channel_ready_for_open 0x%02x", channel->state_var); 1126 if ((channel->state_var & L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_RSP) == 0) return 0; 1127 if ((channel->state_var & L2CAP_CHANNEL_STATE_VAR_SENT_CONF_RSP) == 0) return 0; 1128 // addition check that fixes re-entrance issue causing l2cap event channel opened twice 1129 if (channel->state == L2CAP_STATE_OPEN) return 0; 1130 return 1; 1131 } 1132 1133 1134 static void l2cap_signaling_handler_channel(l2cap_channel_t *channel, uint8_t *command){ 1135 1136 uint8_t code = command[L2CAP_SIGNALING_COMMAND_CODE_OFFSET]; 1137 uint8_t identifier = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 1138 uint16_t result = 0; 1139 1140 log_info("L2CAP signaling handler code %u, state %u", code, channel->state); 1141 1142 // handle DISCONNECT REQUESTS seperately 1143 if (code == DISCONNECTION_REQUEST){ 1144 switch (channel->state){ 1145 case L2CAP_STATE_CONFIG: 1146 case L2CAP_STATE_OPEN: 1147 case L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST: 1148 case L2CAP_STATE_WAIT_DISCONNECT: 1149 l2cap_handle_disconnect_request(channel, identifier); 1150 break; 1151 1152 default: 1153 // ignore in other states 1154 break; 1155 } 1156 return; 1157 } 1158 1159 // @STATEMACHINE(l2cap) 1160 switch (channel->state) { 1161 1162 case L2CAP_STATE_WAIT_CONNECT_RSP: 1163 switch (code){ 1164 case CONNECTION_RESPONSE: 1165 l2cap_stop_rtx(channel); 1166 result = little_endian_read_16 (command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+4); 1167 switch (result) { 1168 case 0: 1169 // successful connection 1170 channel->remote_cid = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 1171 channel->state = L2CAP_STATE_CONFIG; 1172 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 1173 break; 1174 case 1: 1175 // connection pending. get some coffee, but start the ERTX 1176 l2cap_start_ertx(channel); 1177 break; 1178 default: 1179 // channel closed 1180 channel->state = L2CAP_STATE_CLOSED; 1181 // map l2cap connection response result to BTstack status enumeration 1182 l2cap_emit_channel_opened(channel, L2CAP_CONNECTION_RESPONSE_RESULT_SUCCESSFUL + result); 1183 1184 // drop link key if security block 1185 if (L2CAP_CONNECTION_RESPONSE_RESULT_SUCCESSFUL + result == L2CAP_CONNECTION_RESPONSE_RESULT_REFUSED_SECURITY){ 1186 hci_drop_link_key_for_bd_addr(channel->address); 1187 } 1188 1189 // discard channel 1190 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 1191 btstack_memory_l2cap_channel_free(channel); 1192 break; 1193 } 1194 break; 1195 1196 default: 1197 //@TODO: implement other signaling packets 1198 break; 1199 } 1200 break; 1201 1202 case L2CAP_STATE_CONFIG: 1203 result = little_endian_read_16 (command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+4); 1204 switch (code) { 1205 case CONFIGURE_REQUEST: 1206 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP); 1207 l2cap_signaling_handle_configure_request(channel, command); 1208 if (!(channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT)){ 1209 // only done if continuation not set 1210 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_REQ); 1211 } 1212 break; 1213 case CONFIGURE_RESPONSE: 1214 l2cap_stop_rtx(channel); 1215 switch (result){ 1216 case 0: // success 1217 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_RSP); 1218 break; 1219 case 4: // pending 1220 l2cap_start_ertx(channel); 1221 break; 1222 default: 1223 // retry on negative result 1224 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 1225 break; 1226 } 1227 break; 1228 default: 1229 break; 1230 } 1231 if (l2cap_channel_ready_for_open(channel)){ 1232 // for open: 1233 channel->state = L2CAP_STATE_OPEN; 1234 l2cap_emit_channel_opened(channel, 0); 1235 } 1236 break; 1237 1238 case L2CAP_STATE_WAIT_DISCONNECT: 1239 switch (code) { 1240 case DISCONNECTION_RESPONSE: 1241 l2cap_finialize_channel_close(channel); 1242 break; 1243 default: 1244 //@TODO: implement other signaling packets 1245 break; 1246 } 1247 break; 1248 1249 case L2CAP_STATE_CLOSED: 1250 // @TODO handle incoming requests 1251 break; 1252 1253 case L2CAP_STATE_OPEN: 1254 //@TODO: implement other signaling packets, e.g. re-configure 1255 break; 1256 default: 1257 break; 1258 } 1259 // log_info("new state %u", channel->state); 1260 } 1261 1262 1263 static void l2cap_signaling_handler_dispatch( hci_con_handle_t handle, uint8_t * command){ 1264 1265 // get code, signalind identifier and command len 1266 uint8_t code = command[L2CAP_SIGNALING_COMMAND_CODE_OFFSET]; 1267 uint8_t sig_id = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 1268 1269 // not for a particular channel, and not CONNECTION_REQUEST, ECHO_[REQUEST|RESPONSE], INFORMATION_REQUEST 1270 if (code < 1 || code == ECHO_RESPONSE || code > INFORMATION_REQUEST){ 1271 l2cap_register_signaling_response(handle, COMMAND_REJECT, sig_id, L2CAP_REJ_CMD_UNKNOWN); 1272 return; 1273 } 1274 1275 // general commands without an assigned channel 1276 switch(code) { 1277 1278 case CONNECTION_REQUEST: { 1279 uint16_t psm = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 1280 uint16_t source_cid = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+2); 1281 l2cap_handle_connection_request(handle, sig_id, psm, source_cid); 1282 return; 1283 } 1284 1285 case ECHO_REQUEST: 1286 l2cap_register_signaling_response(handle, code, sig_id, 0); 1287 return; 1288 1289 case INFORMATION_REQUEST: { 1290 uint16_t infoType = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 1291 l2cap_register_signaling_response(handle, code, sig_id, infoType); 1292 return; 1293 } 1294 1295 default: 1296 break; 1297 } 1298 1299 1300 // Get potential destination CID 1301 uint16_t dest_cid = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 1302 1303 // Find channel for this sig_id and connection handle 1304 btstack_linked_list_iterator_t it; 1305 btstack_linked_list_iterator_init(&it, &l2cap_channels); 1306 while (btstack_linked_list_iterator_has_next(&it)){ 1307 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 1308 if (channel->handle != handle) continue; 1309 if (code & 1) { 1310 // match odd commands (responses) by previous signaling identifier 1311 if (channel->local_sig_id == sig_id) { 1312 l2cap_signaling_handler_channel(channel, command); 1313 break; 1314 } 1315 } else { 1316 // match even commands (requests) by local channel id 1317 if (channel->local_cid == dest_cid) { 1318 l2cap_signaling_handler_channel(channel, command); 1319 break; 1320 } 1321 } 1322 } 1323 } 1324 1325 static void l2cap_acl_handler( uint8_t *packet, uint16_t size ){ 1326 1327 // Get Channel ID 1328 uint16_t channel_id = READ_L2CAP_CHANNEL_ID(packet); 1329 hci_con_handle_t handle = READ_ACL_CONNECTION_HANDLE(packet); 1330 1331 switch (channel_id) { 1332 1333 case L2CAP_CID_SIGNALING: { 1334 1335 uint16_t command_offset = 8; 1336 while (command_offset < size) { 1337 1338 // handle signaling commands 1339 l2cap_signaling_handler_dispatch(handle, &packet[command_offset]); 1340 1341 // increment command_offset 1342 command_offset += L2CAP_SIGNALING_COMMAND_DATA_OFFSET + little_endian_read_16(packet, command_offset + L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET); 1343 } 1344 break; 1345 } 1346 1347 case L2CAP_CID_ATTRIBUTE_PROTOCOL: 1348 if (attribute_protocol_packet_handler) { 1349 (*attribute_protocol_packet_handler)(ATT_DATA_PACKET, handle, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1350 } 1351 break; 1352 1353 case L2CAP_CID_SECURITY_MANAGER_PROTOCOL: 1354 if (security_protocol_packet_handler) { 1355 (*security_protocol_packet_handler)(SM_DATA_PACKET, handle, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1356 } 1357 break; 1358 1359 case L2CAP_CID_CONNECTIONLESS_CHANNEL: 1360 if (connectionless_channel_packet_handler) { 1361 (*connectionless_channel_packet_handler)(UCD_DATA_PACKET, handle, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1362 } 1363 break; 1364 1365 case L2CAP_CID_SIGNALING_LE: { 1366 switch (packet[8]){ 1367 case CONNECTION_PARAMETER_UPDATE_RESPONSE: { 1368 uint16_t result = little_endian_read_16(packet, 12); 1369 l2cap_emit_connection_parameter_update_response(handle, result); 1370 break; 1371 } 1372 case CONNECTION_PARAMETER_UPDATE_REQUEST: { 1373 uint8_t event[10]; 1374 event[0] = L2CAP_EVENT_CONNECTION_PARAMETER_UPDATE_REQUEST; 1375 event[1] = 8; 1376 memcpy(&event[2], &packet[12], 8); 1377 1378 hci_connection_t * connection = hci_connection_for_handle(handle); 1379 if (connection){ 1380 if (connection->role != HCI_ROLE_MASTER){ 1381 // reject command without notifying upper layer when not in master role 1382 uint8_t sig_id = packet[COMPLETE_L2CAP_HEADER + 1]; 1383 l2cap_register_signaling_response(handle, COMMAND_REJECT_LE, sig_id, L2CAP_REJ_CMD_UNKNOWN); 1384 break; 1385 } 1386 int update_parameter = 1; 1387 le_connection_parameter_range_t existing_range; 1388 gap_le_get_connection_parameter_range(existing_range); 1389 uint16_t le_conn_interval_min = little_endian_read_16(packet,12); 1390 uint16_t le_conn_interval_max = little_endian_read_16(packet,14); 1391 uint16_t le_conn_latency = little_endian_read_16(packet,16); 1392 uint16_t le_supervision_timeout = little_endian_read_16(packet,18); 1393 1394 if (le_conn_interval_min < existing_range.le_conn_interval_min) update_parameter = 0; 1395 if (le_conn_interval_max > existing_range.le_conn_interval_max) update_parameter = 0; 1396 1397 if (le_conn_latency < existing_range.le_conn_latency_min) update_parameter = 0; 1398 if (le_conn_latency > existing_range.le_conn_latency_max) update_parameter = 0; 1399 1400 if (le_supervision_timeout < existing_range.le_supervision_timeout_min) update_parameter = 0; 1401 if (le_supervision_timeout > existing_range.le_supervision_timeout_max) update_parameter = 0; 1402 1403 if (update_parameter){ 1404 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_RESPONSE; 1405 connection->le_conn_interval_min = le_conn_interval_min; 1406 connection->le_conn_interval_max = le_conn_interval_max; 1407 connection->le_conn_latency = le_conn_latency; 1408 connection->le_supervision_timeout = le_supervision_timeout; 1409 } else { 1410 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_DENY; 1411 } 1412 connection->le_con_param_update_identifier = packet[COMPLETE_L2CAP_HEADER + 1]; 1413 } 1414 1415 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 1416 (*packet_handler)( HCI_EVENT_PACKET, 0, event, sizeof(event)); 1417 1418 break; 1419 } 1420 default: { 1421 uint8_t sig_id = packet[COMPLETE_L2CAP_HEADER + 1]; 1422 l2cap_register_signaling_response(handle, COMMAND_REJECT_LE, sig_id, L2CAP_REJ_CMD_UNKNOWN); 1423 break; 1424 } 1425 } 1426 break; 1427 } 1428 1429 default: { 1430 // Find channel for this channel_id and connection handle 1431 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(channel_id); 1432 if (channel) { 1433 l2cap_dispatch(channel, L2CAP_DATA_PACKET, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1434 } 1435 break; 1436 } 1437 } 1438 } 1439 1440 static void l2cap_packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){ 1441 switch (packet_type) { 1442 case HCI_EVENT_PACKET: 1443 l2cap_event_handler(packet, size); 1444 break; 1445 case HCI_ACL_DATA_PACKET: 1446 l2cap_acl_handler(packet, size); 1447 break; 1448 default: 1449 break; 1450 } 1451 l2cap_run(); 1452 } 1453 1454 // finalize closed channel - l2cap_handle_disconnect_request & DISCONNECTION_RESPONSE 1455 void l2cap_finialize_channel_close(l2cap_channel_t *channel){ 1456 channel->state = L2CAP_STATE_CLOSED; 1457 l2cap_emit_channel_closed(channel); 1458 // discard channel 1459 l2cap_stop_rtx(channel); 1460 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 1461 btstack_memory_l2cap_channel_free(channel); 1462 } 1463 1464 static l2cap_service_t * l2cap_get_service_internal(btstack_linked_list_t * services, uint16_t psm){ 1465 btstack_linked_list_iterator_t it; 1466 btstack_linked_list_iterator_init(&it, services); 1467 while (btstack_linked_list_iterator_has_next(&it)){ 1468 l2cap_service_t * service = (l2cap_service_t *) btstack_linked_list_iterator_next(&it); 1469 if ( service->psm == psm){ 1470 return service; 1471 }; 1472 } 1473 return NULL; 1474 } 1475 1476 static inline l2cap_service_t * l2cap_get_service(uint16_t psm){ 1477 return l2cap_get_service_internal(&l2cap_services, psm); 1478 } 1479 1480 1481 uint8_t l2cap_register_service(btstack_packet_handler_t service_packet_handler, uint16_t psm, uint16_t mtu, gap_security_level_t security_level){ 1482 1483 log_info("L2CAP_REGISTER_SERVICE psm 0x%x mtu %u", psm, mtu); 1484 1485 // check for alread registered psm 1486 // TODO: emit error event 1487 l2cap_service_t *service = l2cap_get_service(psm); 1488 if (service) { 1489 log_error("l2cap_register_service: PSM %u already registered", psm); 1490 return L2CAP_SERVICE_ALREADY_REGISTERED; 1491 } 1492 1493 // alloc structure 1494 // TODO: emit error event 1495 service = btstack_memory_l2cap_service_get(); 1496 if (!service) { 1497 log_error("l2cap_register_service: no memory for l2cap_service_t"); 1498 return BTSTACK_MEMORY_ALLOC_FAILED; 1499 } 1500 1501 // fill in 1502 service->psm = psm; 1503 service->mtu = mtu; 1504 service->packet_handler = service_packet_handler; 1505 service->required_security_level = security_level; 1506 1507 // add to services list 1508 btstack_linked_list_add(&l2cap_services, (btstack_linked_item_t *) service); 1509 1510 // enable page scan 1511 hci_connectable_control(1); 1512 1513 return 0; 1514 } 1515 1516 void l2cap_unregister_service(uint16_t psm){ 1517 1518 log_info("L2CAP_UNREGISTER_SERVICE psm 0x%x", psm); 1519 1520 l2cap_service_t *service = l2cap_get_service(psm); 1521 if (!service) return; 1522 btstack_linked_list_remove(&l2cap_services, (btstack_linked_item_t *) service); 1523 btstack_memory_l2cap_service_free(service); 1524 1525 // disable page scan when no services registered 1526 if (!btstack_linked_list_empty(&l2cap_services)) return; 1527 hci_connectable_control(0); 1528 } 1529 1530 // Bluetooth 4.0 - allows to register handler for Attribute Protocol and Security Manager Protocol 1531 void l2cap_register_fixed_channel(btstack_packet_handler_t the_packet_handler, uint16_t channel_id) { 1532 switch(channel_id){ 1533 case L2CAP_CID_ATTRIBUTE_PROTOCOL: 1534 attribute_protocol_packet_handler = the_packet_handler; 1535 break; 1536 case L2CAP_CID_SECURITY_MANAGER_PROTOCOL: 1537 security_protocol_packet_handler = the_packet_handler; 1538 break; 1539 case L2CAP_CID_CONNECTIONLESS_CHANNEL: 1540 connectionless_channel_packet_handler = the_packet_handler; 1541 break; 1542 } 1543 } 1544 1545 #ifdef ENABLE_BLE 1546 1547 1548 #if 0 1549 static inline l2cap_service_t * l2cap_le_get_service(uint16_t psm){ 1550 return l2cap_get_service_internal(&l2cap_le_services, psm); 1551 } 1552 /** 1553 * @brief Regster L2CAP LE Credit Based Flow Control Mode service 1554 * @param 1555 */ 1556 void l2cap_le_register_service(btstack_packet_handler_t packet_handler, uint16_t psm, 1557 uint16_t mtu, uint16_t mps, uint16_t initial_credits, gap_security_level_t security_level){ 1558 1559 log_info("L2CAP_LE_REGISTER_SERVICE psm 0x%x mtu %u connection %p", psm, mtu, connection); 1560 1561 // check for alread registered psm 1562 // TODO: emit error event 1563 l2cap_service_t *service = l2cap_le_get_service(psm); 1564 if (service) { 1565 log_error("l2cap_le_register_service_internal: PSM %u already registered", psm); 1566 l2cap_emit_service_registered(connection, L2CAP_SERVICE_ALREADY_REGISTERED, psm); 1567 return; 1568 } 1569 1570 // alloc structure 1571 // TODO: emit error event 1572 service = btstack_memory_l2cap_service_get(); 1573 if (!service) { 1574 log_error("l2cap_register_service_internal: no memory for l2cap_service_t"); 1575 l2cap_emit_service_registered(connection, BTSTACK_MEMORY_ALLOC_FAILED, psm); 1576 return; 1577 } 1578 1579 // fill in 1580 service->psm = psm; 1581 service->mtu = mtu; 1582 service->mps = mps; 1583 service->packet_handler = packet_handler; 1584 service->required_security_level = security_level; 1585 1586 // add to services list 1587 btstack_linked_list_add(&l2cap_le_services, (btstack_linked_item_t *) service); 1588 1589 // done 1590 l2cap_emit_service_registered(connection, 0, psm); 1591 } 1592 1593 void l2cap_le_unregister_service(uint16_t psm) { 1594 1595 log_info("L2CAP_LE_UNREGISTER_SERVICE psm 0x%x", psm); 1596 1597 l2cap_service_t *service = l2cap_le_get_service(psm); 1598 if (!service) return; 1599 btstack_linked_list_remove(&l2cap_le_services, (btstack_linked_item_t *) service); 1600 btstack_memory_l2cap_service_free(service); 1601 } 1602 #endif 1603 #endif 1604