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_event.h" 51 #include "btstack_memory.h" 52 53 #include <stdarg.h> 54 #include <string.h> 55 56 #include <stdio.h> 57 58 // nr of buffered acl packets in outgoing queue to get max performance 59 #define NR_BUFFERED_ACL_PACKETS 3 60 61 // used to cache l2cap rejects, echo, and informational requests 62 #define NR_PENDING_SIGNALING_RESPONSES 3 63 64 // offsets for L2CAP SIGNALING COMMANDS 65 #define L2CAP_SIGNALING_COMMAND_CODE_OFFSET 0 66 #define L2CAP_SIGNALING_COMMAND_SIGID_OFFSET 1 67 #define L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET 2 68 #define L2CAP_SIGNALING_COMMAND_DATA_OFFSET 4 69 70 // internal table 71 #define L2CAP_FIXED_CHANNEL_TABLE_INDEX_ATTRIBUTE_PROTOCOL 0 72 #define L2CAP_FIXED_CHANNEL_TABLE_INDEX_SECURITY_MANAGER_PROTOCOL 1 73 #define L2CAP_FIXED_CHANNEL_TABLE_INDEX_CONNECTIONLESS_CHANNEL 2 74 #define L2CAP_FIXED_CHANNEL_TABLE_SIZE (L2CAP_FIXED_CHANNEL_TABLE_INDEX_CONNECTIONLESS_CHANNEL+1) 75 76 // prototypes 77 static void l2cap_finialize_channel_close(l2cap_channel_t *channel); 78 static inline l2cap_service_t * l2cap_get_service(uint16_t psm); 79 static void l2cap_emit_channel_opened(l2cap_channel_t *channel, uint8_t status); 80 static void l2cap_emit_can_send_now(btstack_packet_handler_t packet_handler, uint16_t channel); 81 static void l2cap_emit_channel_closed(l2cap_channel_t *channel); 82 static void l2cap_emit_connection_request(l2cap_channel_t *channel); 83 static int l2cap_channel_ready_for_open(l2cap_channel_t *channel); 84 static void l2cap_hci_event_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size); 85 static void l2cap_acl_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size ); 86 static void l2cap_notify_channel_can_send(void); 87 88 typedef struct l2cap_fixed_channel { 89 btstack_packet_handler_t callback; 90 uint8_t waiting_for_can_send_now; 91 } l2cap_fixed_channel_t; 92 93 static btstack_linked_list_t l2cap_channels; 94 static btstack_linked_list_t l2cap_services; 95 static btstack_linked_list_t l2cap_le_channels; 96 static btstack_linked_list_t l2cap_le_services; 97 98 // used to cache l2cap rejects, echo, and informational requests 99 static l2cap_signaling_response_t signaling_responses[NR_PENDING_SIGNALING_RESPONSES]; 100 static int signaling_responses_pending; 101 102 static uint8_t require_security_level2_for_outgoing_sdp; 103 104 static btstack_packet_callback_registration_t hci_event_callback_registration; 105 106 static btstack_packet_handler_t l2cap_event_packet_handler; 107 static l2cap_fixed_channel_t fixed_channels[L2CAP_FIXED_CHANNEL_TABLE_SIZE]; 108 109 static uint16_t l2cap_fixed_channel_table_channel_id_for_index(int index){ 110 switch (index){ 111 case L2CAP_FIXED_CHANNEL_TABLE_INDEX_ATTRIBUTE_PROTOCOL: 112 return L2CAP_CID_ATTRIBUTE_PROTOCOL; 113 case L2CAP_FIXED_CHANNEL_TABLE_INDEX_SECURITY_MANAGER_PROTOCOL: 114 return L2CAP_CID_SECURITY_MANAGER_PROTOCOL; 115 case L2CAP_FIXED_CHANNEL_TABLE_INDEX_CONNECTIONLESS_CHANNEL: 116 return L2CAP_CID_CONNECTIONLESS_CHANNEL; 117 default: 118 return 0; 119 } 120 } 121 static int l2cap_fixed_channel_table_index_for_channel_id(uint16_t channel_id){ 122 switch (channel_id){ 123 case L2CAP_CID_ATTRIBUTE_PROTOCOL: 124 return L2CAP_FIXED_CHANNEL_TABLE_INDEX_ATTRIBUTE_PROTOCOL; 125 case L2CAP_CID_SECURITY_MANAGER_PROTOCOL: 126 return L2CAP_FIXED_CHANNEL_TABLE_INDEX_SECURITY_MANAGER_PROTOCOL; 127 case L2CAP_CID_CONNECTIONLESS_CHANNEL: 128 return L2CAP_FIXED_CHANNEL_TABLE_INDEX_CONNECTIONLESS_CHANNEL; 129 default: 130 return -1; 131 } 132 } 133 134 static int l2cap_fixed_channel_table_index_is_le(int index){ 135 if (index == L2CAP_CID_CONNECTIONLESS_CHANNEL) return 0; 136 return 1; 137 } 138 139 void l2cap_init(void){ 140 signaling_responses_pending = 0; 141 142 l2cap_channels = NULL; 143 l2cap_services = NULL; 144 l2cap_le_services = NULL; 145 l2cap_le_channels = NULL; 146 147 l2cap_event_packet_handler = NULL; 148 memset(fixed_channels, 0, sizeof(fixed_channels)); 149 150 require_security_level2_for_outgoing_sdp = 0; 151 152 // 153 // register callback with HCI 154 // 155 hci_event_callback_registration.callback = &l2cap_hci_event_handler; 156 hci_add_event_handler(&hci_event_callback_registration); 157 158 hci_register_acl_packet_handler(&l2cap_acl_handler); 159 160 gap_connectable_control(0); // no services yet 161 } 162 163 void l2cap_register_packet_handler(void (*handler)(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size)){ 164 l2cap_event_packet_handler = handler; 165 } 166 167 static void l2cap_dispatch_to_channel(l2cap_channel_t *channel, uint8_t type, uint8_t * data, uint16_t size){ 168 (* (channel->packet_handler))(type, channel->local_cid, data, size); 169 } 170 171 void l2cap_emit_channel_opened(l2cap_channel_t *channel, uint8_t status) { 172 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", 173 status, bd_addr_to_str(channel->address), channel->con_handle, channel->psm, 174 channel->local_cid, channel->remote_cid, channel->local_mtu, channel->remote_mtu, channel->flush_timeout); 175 uint8_t event[23]; 176 event[0] = L2CAP_EVENT_CHANNEL_OPENED; 177 event[1] = sizeof(event) - 2; 178 event[2] = status; 179 reverse_bd_addr(channel->address, &event[3]); 180 little_endian_store_16(event, 9, channel->con_handle); 181 little_endian_store_16(event, 11, channel->psm); 182 little_endian_store_16(event, 13, channel->local_cid); 183 little_endian_store_16(event, 15, channel->remote_cid); 184 little_endian_store_16(event, 17, channel->local_mtu); 185 little_endian_store_16(event, 19, channel->remote_mtu); 186 little_endian_store_16(event, 21, channel->flush_timeout); 187 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 188 l2cap_dispatch_to_channel(channel, HCI_EVENT_PACKET, event, sizeof(event)); 189 } 190 191 void l2cap_emit_channel_closed(l2cap_channel_t *channel) { 192 log_info("L2CAP_EVENT_CHANNEL_CLOSED local_cid 0x%x", channel->local_cid); 193 uint8_t event[4]; 194 event[0] = L2CAP_EVENT_CHANNEL_CLOSED; 195 event[1] = sizeof(event) - 2; 196 little_endian_store_16(event, 2, channel->local_cid); 197 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 198 l2cap_dispatch_to_channel(channel, HCI_EVENT_PACKET, event, sizeof(event)); 199 } 200 201 void l2cap_emit_connection_request(l2cap_channel_t *channel) { 202 log_info("L2CAP_EVENT_INCOMING_CONNECTION addr %s handle 0x%x psm 0x%x local_cid 0x%x remote_cid 0x%x", 203 bd_addr_to_str(channel->address), channel->con_handle, channel->psm, channel->local_cid, channel->remote_cid); 204 uint8_t event[16]; 205 event[0] = L2CAP_EVENT_INCOMING_CONNECTION; 206 event[1] = sizeof(event) - 2; 207 reverse_bd_addr(channel->address, &event[2]); 208 little_endian_store_16(event, 8, channel->con_handle); 209 little_endian_store_16(event, 10, channel->psm); 210 little_endian_store_16(event, 12, channel->local_cid); 211 little_endian_store_16(event, 14, channel->remote_cid); 212 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 213 l2cap_dispatch_to_channel(channel, HCI_EVENT_PACKET, event, sizeof(event)); 214 } 215 216 static void l2cap_emit_can_send_now(btstack_packet_handler_t packet_handler, uint16_t channel) { 217 log_info("L2CAP_EVENT_CHANNEL_CAN_SEND_NOW local_cid 0x%x", channel); 218 uint8_t event[4]; 219 event[0] = L2CAP_EVENT_CAN_SEND_NOW; 220 event[1] = sizeof(event) - 2; 221 little_endian_store_16(event, 2, channel); 222 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 223 packet_handler(HCI_EVENT_PACKET, channel, event, sizeof(event)); 224 } 225 226 static void l2cap_emit_connection_parameter_update_response(hci_con_handle_t con_handle, uint16_t result){ 227 uint8_t event[6]; 228 event[0] = L2CAP_EVENT_CONNECTION_PARAMETER_UPDATE_RESPONSE; 229 event[1] = 4; 230 little_endian_store_16(event, 2, con_handle); 231 little_endian_store_16(event, 4, result); 232 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 233 if (!l2cap_event_packet_handler) return; 234 (*l2cap_event_packet_handler)(HCI_EVENT_PACKET, 0, event, sizeof(event)); 235 } 236 237 static l2cap_channel_t * l2cap_get_channel_for_local_cid(uint16_t local_cid){ 238 btstack_linked_list_iterator_t it; 239 btstack_linked_list_iterator_init(&it, &l2cap_channels); 240 while (btstack_linked_list_iterator_has_next(&it)){ 241 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 242 if ( channel->local_cid == local_cid) { 243 return channel; 244 } 245 } 246 return NULL; 247 } 248 249 /// 250 251 void l2cap_request_can_send_now_event(uint16_t local_cid){ 252 l2cap_channel_t *channel = l2cap_get_channel_for_local_cid(local_cid); 253 if (!channel) return; 254 channel->waiting_for_can_send_now = 1; 255 l2cap_notify_channel_can_send(); 256 } 257 258 void l2cap_request_can_send_fix_channel_now_event(hci_con_handle_t con_handle, uint16_t channel_id){ 259 int index = l2cap_fixed_channel_table_index_for_channel_id(channel_id); 260 if (index < 0) return; 261 fixed_channels[index].waiting_for_can_send_now = 1; 262 l2cap_notify_channel_can_send(); 263 } 264 265 /// 266 267 int l2cap_can_send_packet_now(uint16_t local_cid){ 268 l2cap_channel_t *channel = l2cap_get_channel_for_local_cid(local_cid); 269 if (!channel) return 0; 270 return hci_can_send_acl_packet_now(channel->con_handle); 271 } 272 273 int l2cap_can_send_prepared_packet_now(uint16_t local_cid){ 274 l2cap_channel_t *channel = l2cap_get_channel_for_local_cid(local_cid); 275 if (!channel) return 0; 276 return hci_can_send_prepared_acl_packet_now(channel->con_handle); 277 } 278 279 int l2cap_can_send_fixed_channel_packet_now(hci_con_handle_t con_handle, uint16_t channel_id){ 280 return hci_can_send_acl_packet_now(con_handle); 281 } 282 283 /// 284 285 uint16_t l2cap_get_remote_mtu_for_local_cid(uint16_t local_cid){ 286 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 287 if (channel) { 288 return channel->remote_mtu; 289 } 290 return 0; 291 } 292 293 static l2cap_channel_t * l2cap_channel_for_rtx_timer(btstack_timer_source_t * ts){ 294 btstack_linked_list_iterator_t it; 295 btstack_linked_list_iterator_init(&it, &l2cap_channels); 296 while (btstack_linked_list_iterator_has_next(&it)){ 297 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 298 if ( &channel->rtx == ts) { 299 return channel; 300 } 301 } 302 return NULL; 303 } 304 305 static void l2cap_rtx_timeout(btstack_timer_source_t * ts){ 306 l2cap_channel_t * channel = l2cap_channel_for_rtx_timer(ts); 307 if (!channel) return; 308 309 log_info("l2cap_rtx_timeout for local cid 0x%02x", channel->local_cid); 310 311 // "When terminating the channel, it is not necessary to send a L2CAP_DisconnectReq 312 // and enter WAIT_DISCONNECT state. Channels can be transitioned directly to the CLOSED state." 313 // notify client 314 l2cap_emit_channel_opened(channel, L2CAP_CONNECTION_RESPONSE_RESULT_RTX_TIMEOUT); 315 316 // discard channel 317 // no need to stop timer here, it is removed from list during timer callback 318 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 319 btstack_memory_l2cap_channel_free(channel); 320 } 321 322 static void l2cap_stop_rtx(l2cap_channel_t * channel){ 323 log_info("l2cap_stop_rtx for local cid 0x%02x", channel->local_cid); 324 btstack_run_loop_remove_timer(&channel->rtx); 325 } 326 327 static void l2cap_start_rtx(l2cap_channel_t * channel){ 328 l2cap_stop_rtx(channel); 329 log_info("l2cap_start_rtx for local cid 0x%02x", channel->local_cid); 330 btstack_run_loop_set_timer_handler(&channel->rtx, l2cap_rtx_timeout); 331 btstack_run_loop_set_timer(&channel->rtx, L2CAP_RTX_TIMEOUT_MS); 332 btstack_run_loop_add_timer(&channel->rtx); 333 } 334 335 static void l2cap_start_ertx(l2cap_channel_t * channel){ 336 log_info("l2cap_start_ertx for local cid 0x%02x", channel->local_cid); 337 l2cap_stop_rtx(channel); 338 btstack_run_loop_set_timer_handler(&channel->rtx, l2cap_rtx_timeout); 339 btstack_run_loop_set_timer(&channel->rtx, L2CAP_ERTX_TIMEOUT_MS); 340 btstack_run_loop_add_timer(&channel->rtx); 341 } 342 343 void l2cap_require_security_level_2_for_outgoing_sdp(void){ 344 require_security_level2_for_outgoing_sdp = 1; 345 } 346 347 static int l2cap_security_level_0_allowed_for_PSM(uint16_t psm){ 348 return (psm == PSM_SDP) && (!require_security_level2_for_outgoing_sdp); 349 } 350 351 static int l2cap_send_signaling_packet(hci_con_handle_t handle, L2CAP_SIGNALING_COMMANDS cmd, uint8_t identifier, ...){ 352 353 if (!hci_can_send_acl_packet_now(handle)){ 354 log_info("l2cap_send_signaling_packet, cannot send"); 355 return BTSTACK_ACL_BUFFERS_FULL; 356 } 357 358 // log_info("l2cap_send_signaling_packet type %u", cmd); 359 hci_reserve_packet_buffer(); 360 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 361 va_list argptr; 362 va_start(argptr, identifier); 363 uint16_t len = l2cap_create_signaling_classic(acl_buffer, handle, cmd, identifier, argptr); 364 va_end(argptr); 365 // log_info("l2cap_send_signaling_packet con %u!", handle); 366 return hci_send_acl_packet_buffer(len); 367 } 368 369 #ifdef ENABLE_BLE 370 static int l2cap_send_le_signaling_packet(hci_con_handle_t handle, L2CAP_SIGNALING_COMMANDS cmd, uint8_t identifier, ...){ 371 372 if (!hci_can_send_acl_packet_now(handle)){ 373 log_info("l2cap_send_signaling_packet, cannot send"); 374 return BTSTACK_ACL_BUFFERS_FULL; 375 } 376 377 // log_info("l2cap_send_signaling_packet type %u", cmd); 378 hci_reserve_packet_buffer(); 379 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 380 va_list argptr; 381 va_start(argptr, identifier); 382 uint16_t len = l2cap_create_signaling_le(acl_buffer, handle, cmd, identifier, argptr); 383 va_end(argptr); 384 // log_info("l2cap_send_signaling_packet con %u!", handle); 385 return hci_send_acl_packet_buffer(len); 386 } 387 #endif 388 389 uint8_t *l2cap_get_outgoing_buffer(void){ 390 return hci_get_outgoing_packet_buffer() + COMPLETE_L2CAP_HEADER; // 8 bytes 391 } 392 393 int l2cap_reserve_packet_buffer(void){ 394 return hci_reserve_packet_buffer(); 395 } 396 397 void l2cap_release_packet_buffer(void){ 398 hci_release_packet_buffer(); 399 } 400 401 402 int l2cap_send_prepared(uint16_t local_cid, uint16_t len){ 403 404 if (!hci_is_packet_buffer_reserved()){ 405 log_error("l2cap_send_prepared called without reserving packet first"); 406 return BTSTACK_ACL_BUFFERS_FULL; 407 } 408 409 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 410 if (!channel) { 411 log_error("l2cap_send_prepared no channel for cid 0x%02x", local_cid); 412 return -1; // TODO: define error 413 } 414 415 if (!hci_can_send_prepared_acl_packet_now(channel->con_handle)){ 416 log_info("l2cap_send_prepared cid 0x%02x, cannot send", local_cid); 417 return BTSTACK_ACL_BUFFERS_FULL; 418 } 419 420 log_debug("l2cap_send_prepared cid 0x%02x, handle %u, 1 credit used", local_cid, channel->con_handle); 421 422 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 423 424 int pb = hci_non_flushable_packet_boundary_flag_supported() ? 0x00 : 0x02; 425 426 // 0 - Connection handle : PB=pb : BC=00 427 little_endian_store_16(acl_buffer, 0, channel->con_handle | (pb << 12) | (0 << 14)); 428 // 2 - ACL length 429 little_endian_store_16(acl_buffer, 2, len + 4); 430 // 4 - L2CAP packet length 431 little_endian_store_16(acl_buffer, 4, len + 0); 432 // 6 - L2CAP channel DEST 433 little_endian_store_16(acl_buffer, 6, channel->remote_cid); 434 // send 435 int err = hci_send_acl_packet_buffer(len+8); 436 437 return err; 438 } 439 440 int l2cap_send_prepared_connectionless(hci_con_handle_t con_handle, uint16_t cid, uint16_t len){ 441 442 if (!hci_is_packet_buffer_reserved()){ 443 log_error("l2cap_send_prepared_connectionless called without reserving packet first"); 444 return BTSTACK_ACL_BUFFERS_FULL; 445 } 446 447 if (!hci_can_send_prepared_acl_packet_now(con_handle)){ 448 log_info("l2cap_send_prepared_connectionless handle 0x%02x, cid 0x%02x, cannot send", con_handle, cid); 449 return BTSTACK_ACL_BUFFERS_FULL; 450 } 451 452 log_debug("l2cap_send_prepared_connectionless handle %u, cid 0x%02x", con_handle, cid); 453 454 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 455 456 int pb = hci_non_flushable_packet_boundary_flag_supported() ? 0x00 : 0x02; 457 458 // 0 - Connection handle : PB=pb : BC=00 459 little_endian_store_16(acl_buffer, 0, con_handle | (pb << 12) | (0 << 14)); 460 // 2 - ACL length 461 little_endian_store_16(acl_buffer, 2, len + 4); 462 // 4 - L2CAP packet length 463 little_endian_store_16(acl_buffer, 4, len + 0); 464 // 6 - L2CAP channel DEST 465 little_endian_store_16(acl_buffer, 6, cid); 466 // send 467 int err = hci_send_acl_packet_buffer(len+8); 468 469 return err; 470 } 471 472 int l2cap_send(uint16_t local_cid, uint8_t *data, uint16_t len){ 473 474 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 475 if (!channel) { 476 log_error("l2cap_send no channel for cid 0x%02x", local_cid); 477 return -1; // TODO: define error 478 } 479 480 if (len > channel->remote_mtu){ 481 log_error("l2cap_send cid 0x%02x, data length exceeds remote MTU.", local_cid); 482 return L2CAP_DATA_LEN_EXCEEDS_REMOTE_MTU; 483 } 484 485 if (!hci_can_send_acl_packet_now(channel->con_handle)){ 486 log_info("l2cap_send cid 0x%02x, cannot send", local_cid); 487 return BTSTACK_ACL_BUFFERS_FULL; 488 } 489 490 hci_reserve_packet_buffer(); 491 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 492 493 memcpy(&acl_buffer[8], data, len); 494 495 return l2cap_send_prepared(local_cid, len); 496 } 497 498 int l2cap_send_connectionless(hci_con_handle_t con_handle, uint16_t cid, uint8_t *data, uint16_t len){ 499 500 if (!hci_can_send_acl_packet_now(con_handle)){ 501 log_info("l2cap_send cid 0x%02x, cannot send", cid); 502 return BTSTACK_ACL_BUFFERS_FULL; 503 } 504 505 hci_reserve_packet_buffer(); 506 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 507 508 memcpy(&acl_buffer[8], data, len); 509 510 return l2cap_send_prepared_connectionless(con_handle, cid, len); 511 } 512 513 int l2cap_send_echo_request(hci_con_handle_t con_handle, uint8_t *data, uint16_t len){ 514 return l2cap_send_signaling_packet(con_handle, ECHO_REQUEST, 0x77, len, data); 515 } 516 517 static inline void channelStateVarSetFlag(l2cap_channel_t *channel, L2CAP_CHANNEL_STATE_VAR flag){ 518 channel->state_var = (L2CAP_CHANNEL_STATE_VAR) (channel->state_var | flag); 519 } 520 521 static inline void channelStateVarClearFlag(l2cap_channel_t *channel, L2CAP_CHANNEL_STATE_VAR flag){ 522 channel->state_var = (L2CAP_CHANNEL_STATE_VAR) (channel->state_var & ~flag); 523 } 524 525 526 527 // MARK: L2CAP_RUN 528 // process outstanding signaling tasks 529 static void l2cap_run(void){ 530 531 // log_info("l2cap_run: entered"); 532 533 // check pending signaling responses 534 while (signaling_responses_pending){ 535 536 hci_con_handle_t handle = signaling_responses[0].handle; 537 538 if (!hci_can_send_acl_packet_now(handle)) break; 539 540 uint8_t sig_id = signaling_responses[0].sig_id; 541 uint16_t infoType = signaling_responses[0].data; // INFORMATION_REQUEST 542 uint16_t result = signaling_responses[0].data; // CONNECTION_REQUEST, COMMAND_REJECT 543 uint8_t response_code = signaling_responses[0].code; 544 545 // remove first item before sending (to avoid sending response mutliple times) 546 signaling_responses_pending--; 547 int i; 548 for (i=0; i < signaling_responses_pending; i++){ 549 memcpy(&signaling_responses[i], &signaling_responses[i+1], sizeof(l2cap_signaling_response_t)); 550 } 551 552 switch (response_code){ 553 case CONNECTION_REQUEST: 554 l2cap_send_signaling_packet(handle, CONNECTION_RESPONSE, sig_id, 0, 0, result, 0); 555 // also disconnect if result is 0x0003 - security blocked 556 if (result == 0x0003){ 557 hci_disconnect_security_block(handle); 558 } 559 break; 560 case ECHO_REQUEST: 561 l2cap_send_signaling_packet(handle, ECHO_RESPONSE, sig_id, 0, NULL); 562 break; 563 case INFORMATION_REQUEST: 564 switch (infoType){ 565 case 1: { // Connectionless MTU 566 uint16_t connectionless_mtu = hci_max_acl_data_packet_length(); 567 l2cap_send_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, infoType, 0, sizeof(connectionless_mtu), &connectionless_mtu); 568 break; 569 } 570 case 2: { // Extended Features Supported 571 // extended features request supported, features: fixed channels, unicast connectionless data reception 572 uint32_t features = 0x280; 573 l2cap_send_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, infoType, 0, sizeof(features), &features); 574 break; 575 } 576 case 3: { // Fixed Channels Supported 577 uint8_t map[8]; 578 memset(map, 0, 8); 579 map[0] = 0x06; // L2CAP Signaling Channel (0x02) + Connectionless reception (0x04) 580 l2cap_send_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, infoType, 0, sizeof(map), &map); 581 break; 582 } 583 default: 584 // all other types are not supported 585 l2cap_send_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, infoType, 1, 0, NULL); 586 break; 587 } 588 break; 589 case COMMAND_REJECT: 590 l2cap_send_signaling_packet(handle, COMMAND_REJECT, sig_id, result, 0, NULL); 591 #ifdef ENABLE_BLE 592 case COMMAND_REJECT_LE: 593 l2cap_send_le_signaling_packet(handle, COMMAND_REJECT, sig_id, result, 0, NULL); 594 break; 595 #endif 596 default: 597 // should not happen 598 break; 599 } 600 } 601 602 uint8_t config_options[4]; 603 btstack_linked_list_iterator_t it; 604 btstack_linked_list_iterator_init(&it, &l2cap_channels); 605 while (btstack_linked_list_iterator_has_next(&it)){ 606 607 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 608 // log_info("l2cap_run: channel %p, state %u, var 0x%02x", channel, channel->state, channel->state_var); 609 switch (channel->state){ 610 611 case L2CAP_STATE_WAIT_INCOMING_SECURITY_LEVEL_UPDATE: 612 case L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT: 613 if (!hci_can_send_acl_packet_now(channel->con_handle)) break; 614 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONN_RESP_PEND) { 615 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONN_RESP_PEND); 616 l2cap_send_signaling_packet(channel->con_handle, CONNECTION_RESPONSE, channel->remote_sig_id, channel->local_cid, channel->remote_cid, 1, 0); 617 } 618 break; 619 620 case L2CAP_STATE_WILL_SEND_CREATE_CONNECTION: 621 if (!hci_can_send_command_packet_now()) break; 622 // send connection request - set state first 623 channel->state = L2CAP_STATE_WAIT_CONNECTION_COMPLETE; 624 // BD_ADDR, Packet_Type, Page_Scan_Repetition_Mode, Reserved, Clock_Offset, Allow_Role_Switch 625 hci_send_cmd(&hci_create_connection, channel->address, hci_usable_acl_packet_types(), 0, 0, 0, 1); 626 break; 627 628 case L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE: 629 if (!hci_can_send_acl_packet_now(channel->con_handle)) break; 630 channel->state = L2CAP_STATE_INVALID; 631 l2cap_send_signaling_packet(channel->con_handle, CONNECTION_RESPONSE, channel->remote_sig_id, channel->local_cid, channel->remote_cid, channel->reason, 0); 632 // discard channel - l2cap_finialize_channel_close without sending l2cap close event 633 l2cap_stop_rtx(channel); 634 btstack_linked_list_iterator_remove(&it); 635 btstack_memory_l2cap_channel_free(channel); 636 break; 637 638 case L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_ACCEPT: 639 if (!hci_can_send_acl_packet_now(channel->con_handle)) break; 640 channel->state = L2CAP_STATE_CONFIG; 641 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 642 l2cap_send_signaling_packet(channel->con_handle, CONNECTION_RESPONSE, channel->remote_sig_id, channel->local_cid, channel->remote_cid, 0, 0); 643 break; 644 645 case L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST: 646 if (!hci_can_send_acl_packet_now(channel->con_handle)) break; 647 // success, start l2cap handshake 648 channel->local_sig_id = l2cap_next_sig_id(); 649 channel->state = L2CAP_STATE_WAIT_CONNECT_RSP; 650 l2cap_send_signaling_packet( channel->con_handle, CONNECTION_REQUEST, channel->local_sig_id, channel->psm, channel->local_cid); 651 l2cap_start_rtx(channel); 652 break; 653 654 case L2CAP_STATE_CONFIG: 655 if (!hci_can_send_acl_packet_now(channel->con_handle)) break; 656 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP){ 657 uint16_t flags = 0; 658 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP); 659 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT) { 660 flags = 1; 661 } else { 662 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SENT_CONF_RSP); 663 } 664 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_INVALID){ 665 l2cap_send_signaling_packet(channel->con_handle, CONFIGURE_RESPONSE, channel->remote_sig_id, channel->remote_cid, flags, L2CAP_CONF_RESULT_UNKNOWN_OPTIONS, 0, NULL); 666 } else if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU){ 667 config_options[0] = 1; // MTU 668 config_options[1] = 2; // len param 669 little_endian_store_16( (uint8_t*)&config_options, 2, channel->remote_mtu); 670 l2cap_send_signaling_packet(channel->con_handle, CONFIGURE_RESPONSE, channel->remote_sig_id, channel->remote_cid, flags, 0, 4, &config_options); 671 channelStateVarClearFlag(channel,L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU); 672 } else { 673 l2cap_send_signaling_packet(channel->con_handle, CONFIGURE_RESPONSE, channel->remote_sig_id, channel->remote_cid, flags, 0, 0, NULL); 674 } 675 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT); 676 } 677 else if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ){ 678 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 679 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SENT_CONF_REQ); 680 channel->local_sig_id = l2cap_next_sig_id(); 681 config_options[0] = 1; // MTU 682 config_options[1] = 2; // len param 683 little_endian_store_16( (uint8_t*)&config_options, 2, channel->local_mtu); 684 l2cap_send_signaling_packet(channel->con_handle, CONFIGURE_REQUEST, channel->local_sig_id, channel->remote_cid, 0, 4, &config_options); 685 l2cap_start_rtx(channel); 686 } 687 if (l2cap_channel_ready_for_open(channel)){ 688 channel->state = L2CAP_STATE_OPEN; 689 l2cap_emit_channel_opened(channel, 0); // success 690 } 691 break; 692 693 case L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE: 694 if (!hci_can_send_acl_packet_now(channel->con_handle)) break; 695 channel->state = L2CAP_STATE_INVALID; 696 l2cap_send_signaling_packet( channel->con_handle, DISCONNECTION_RESPONSE, channel->remote_sig_id, channel->local_cid, channel->remote_cid); 697 // 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 :) 698 l2cap_finialize_channel_close(channel); // -- remove from list 699 break; 700 701 case L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST: 702 if (!hci_can_send_acl_packet_now(channel->con_handle)) break; 703 channel->local_sig_id = l2cap_next_sig_id(); 704 channel->state = L2CAP_STATE_WAIT_DISCONNECT; 705 l2cap_send_signaling_packet( channel->con_handle, DISCONNECTION_REQUEST, channel->local_sig_id, channel->remote_cid, channel->local_cid); 706 break; 707 default: 708 break; 709 } 710 } 711 712 #ifdef ENABLE_BLE 713 // send l2cap con paramter update if necessary 714 hci_connections_get_iterator(&it); 715 while(btstack_linked_list_iterator_has_next(&it)){ 716 hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 717 if (connection->address_type != BD_ADDR_TYPE_LE_PUBLIC && connection->address_type != BD_ADDR_TYPE_LE_RANDOM) continue; 718 if (!hci_can_send_acl_packet_now(connection->con_handle)) continue; 719 switch (connection->le_con_parameter_update_state){ 720 case CON_PARAMETER_UPDATE_SEND_REQUEST: 721 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE; 722 l2cap_send_le_signaling_packet(connection->con_handle, CONNECTION_PARAMETER_UPDATE_REQUEST, connection->le_con_param_update_identifier, 723 connection->le_conn_interval_min, connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout); 724 break; 725 case CON_PARAMETER_UPDATE_SEND_RESPONSE: 726 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS; 727 l2cap_send_le_signaling_packet(connection->con_handle, CONNECTION_PARAMETER_UPDATE_RESPONSE, connection->le_con_param_update_identifier, 0); 728 break; 729 case CON_PARAMETER_UPDATE_DENY: 730 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE; 731 l2cap_send_le_signaling_packet(connection->con_handle, CONNECTION_PARAMETER_UPDATE_RESPONSE, connection->le_con_param_update_identifier, 1); 732 break; 733 default: 734 break; 735 } 736 } 737 #endif 738 739 // log_info("l2cap_run: exit"); 740 } 741 742 uint16_t l2cap_max_mtu(void){ 743 return HCI_ACL_PAYLOAD_SIZE - L2CAP_HEADER_SIZE; 744 } 745 746 uint16_t l2cap_max_le_mtu(void){ 747 return l2cap_max_mtu(); 748 } 749 750 static void l2cap_handle_connection_complete(hci_con_handle_t con_handle, l2cap_channel_t * channel){ 751 if (channel->state == L2CAP_STATE_WAIT_CONNECTION_COMPLETE || channel->state == L2CAP_STATE_WILL_SEND_CREATE_CONNECTION) { 752 log_info("l2cap_handle_connection_complete expected state"); 753 // success, start l2cap handshake 754 channel->con_handle = con_handle; 755 // check remote SSP feature first 756 channel->state = L2CAP_STATE_WAIT_REMOTE_SUPPORTED_FEATURES; 757 } 758 } 759 760 static void l2cap_handle_remote_supported_features_received(l2cap_channel_t * channel){ 761 if (channel->state != L2CAP_STATE_WAIT_REMOTE_SUPPORTED_FEATURES) return; 762 763 // we have been waiting for remote supported features, if both support SSP, 764 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)); 765 if (gap_ssp_supported_on_both_sides(channel->con_handle) && !l2cap_security_level_0_allowed_for_PSM(channel->psm)){ 766 // request security level 2 767 channel->state = L2CAP_STATE_WAIT_OUTGOING_SECURITY_LEVEL_UPDATE; 768 gap_request_security_level(channel->con_handle, LEVEL_2); 769 return; 770 } 771 // fine, go ahead 772 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST; 773 } 774 775 static l2cap_channel_t * l2cap_create_channel_entry(btstack_packet_handler_t packet_handler, bd_addr_t address, bd_addr_type_t address_type, 776 uint16_t psm, uint16_t local_mtu, gap_security_level_t security_level){ 777 778 l2cap_channel_t * channel = btstack_memory_l2cap_channel_get(); 779 if (!channel) { 780 return NULL; 781 } 782 783 // Init memory (make valgrind happy) 784 memset(channel, 0, sizeof(l2cap_channel_t)); 785 786 // fill in 787 channel->packet_handler = packet_handler; 788 bd_addr_copy(channel->address, address); 789 channel->address_type = address_type; 790 channel->psm = psm; 791 channel->local_mtu = local_mtu; 792 channel->remote_mtu = L2CAP_MINIMAL_MTU; 793 channel->required_security_level = security_level; 794 795 // 796 channel->local_cid = l2cap_next_local_cid(); 797 channel->con_handle = 0; 798 799 // set initial state 800 channel->state = L2CAP_STATE_WILL_SEND_CREATE_CONNECTION; 801 channel->state_var = L2CAP_CHANNEL_STATE_VAR_NONE; 802 channel->remote_sig_id = L2CAP_SIG_ID_INVALID; 803 channel->local_sig_id = L2CAP_SIG_ID_INVALID; 804 return channel; 805 } 806 807 /** 808 * @brief Creates L2CAP channel to the PSM of a remote device with baseband address. A new baseband connection will be initiated if necessary. 809 * @param packet_handler 810 * @param address 811 * @param psm 812 * @param mtu 813 * @param local_cid 814 */ 815 816 uint8_t l2cap_create_channel(btstack_packet_handler_t channel_packet_handler, bd_addr_t address, uint16_t psm, uint16_t local_mtu, uint16_t * out_local_cid){ 817 log_info("L2CAP_CREATE_CHANNEL addr %s psm 0x%x mtu %u", bd_addr_to_str(address), psm, local_mtu); 818 819 if (local_mtu > l2cap_max_mtu()) { 820 local_mtu = l2cap_max_mtu(); 821 } 822 823 l2cap_channel_t * channel = l2cap_create_channel_entry(channel_packet_handler, address, BD_ADDR_TYPE_CLASSIC, psm, local_mtu, LEVEL_0); 824 if (!channel) { 825 return BTSTACK_MEMORY_ALLOC_FAILED; 826 } 827 828 // add to connections list 829 btstack_linked_list_add(&l2cap_channels, (btstack_linked_item_t *) channel); 830 831 // store local_cid 832 if (out_local_cid){ 833 *out_local_cid = channel->local_cid; 834 } 835 836 // check if hci connection is already usable 837 hci_connection_t * conn = hci_connection_for_bd_addr_and_type(address, BD_ADDR_TYPE_CLASSIC); 838 if (conn){ 839 log_info("l2cap_create_channel, hci connection already exists"); 840 l2cap_handle_connection_complete(conn->con_handle, channel); 841 // check if remote supported fearures are already received 842 if (conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) { 843 l2cap_handle_remote_supported_features_received(channel); 844 } 845 } 846 847 l2cap_run(); 848 849 return 0; 850 } 851 852 void 853 l2cap_disconnect(uint16_t local_cid, uint8_t reason){ 854 log_info("L2CAP_DISCONNECT local_cid 0x%x reason 0x%x", local_cid, reason); 855 // find channel for local_cid 856 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 857 if (channel) { 858 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST; 859 } 860 // process 861 l2cap_run(); 862 } 863 864 static void l2cap_handle_connection_failed_for_addr(bd_addr_t address, uint8_t status){ 865 btstack_linked_list_iterator_t it; 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 ( bd_addr_cmp( channel->address, address) != 0) continue; 870 // channel for this address found 871 switch (channel->state){ 872 case L2CAP_STATE_WAIT_CONNECTION_COMPLETE: 873 case L2CAP_STATE_WILL_SEND_CREATE_CONNECTION: 874 // failure, forward error code 875 l2cap_emit_channel_opened(channel, status); 876 // discard channel 877 l2cap_stop_rtx(channel); 878 btstack_linked_list_iterator_remove(&it); 879 btstack_memory_l2cap_channel_free(channel); 880 break; 881 default: 882 break; 883 } 884 } 885 } 886 887 static void l2cap_handle_connection_success_for_addr(bd_addr_t address, hci_con_handle_t handle){ 888 btstack_linked_list_iterator_t it; 889 btstack_linked_list_iterator_init(&it, &l2cap_channels); 890 while (btstack_linked_list_iterator_has_next(&it)){ 891 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 892 if ( ! bd_addr_cmp( channel->address, address) ){ 893 l2cap_handle_connection_complete(handle, channel); 894 } 895 } 896 // process 897 l2cap_run(); 898 } 899 900 static void l2cap_notify_channel_can_send(void){ 901 btstack_linked_list_iterator_t it; 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->waiting_for_can_send_now) continue; 906 if (!hci_can_send_acl_packet_now(channel->con_handle)) continue; 907 channel->waiting_for_can_send_now = 0; 908 l2cap_emit_can_send_now(channel->packet_handler, channel->local_cid); 909 } 910 911 int i; 912 for (i=0;i<L2CAP_FIXED_CHANNEL_TABLE_SIZE;i++){ 913 if (!fixed_channels[i].callback) continue; 914 if (!fixed_channels[i].waiting_for_can_send_now) continue; 915 int can_send; 916 if (l2cap_fixed_channel_table_index_is_le(i)){ 917 can_send = hci_can_send_acl_le_packet_now(); 918 } else { 919 can_send = hci_can_send_acl_classic_packet_now(); 920 } 921 if (!can_send) continue; 922 fixed_channels[i].waiting_for_can_send_now = 0; 923 l2cap_emit_can_send_now(fixed_channels[i].callback, l2cap_fixed_channel_table_channel_id_for_index(i)); 924 } 925 } 926 927 static void l2cap_hci_event_handler(uint8_t packet_type, uint16_t cid, uint8_t *packet, uint16_t size){ 928 929 bd_addr_t address; 930 hci_con_handle_t handle; 931 btstack_linked_list_iterator_t it; 932 int hci_con_used; 933 934 switch(hci_event_packet_get_type(packet)){ 935 936 // handle connection complete events 937 case HCI_EVENT_CONNECTION_COMPLETE: 938 reverse_bd_addr(&packet[5], address); 939 if (packet[2] == 0){ 940 handle = little_endian_read_16(packet, 3); 941 l2cap_handle_connection_success_for_addr(address, handle); 942 } else { 943 l2cap_handle_connection_failed_for_addr(address, packet[2]); 944 } 945 break; 946 947 // handle successful create connection cancel command 948 case HCI_EVENT_COMMAND_COMPLETE: 949 if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_create_connection_cancel)) { 950 if (packet[5] == 0){ 951 reverse_bd_addr(&packet[6], address); 952 // CONNECTION TERMINATED BY LOCAL HOST (0X16) 953 l2cap_handle_connection_failed_for_addr(address, 0x16); 954 } 955 } 956 l2cap_run(); // try sending signaling packets first 957 break; 958 959 case HCI_EVENT_COMMAND_STATUS: 960 l2cap_run(); // try sending signaling packets first 961 break; 962 963 // handle disconnection complete events 964 case HCI_EVENT_DISCONNECTION_COMPLETE: 965 // send l2cap disconnect events for all channels on this handle and free them 966 handle = little_endian_read_16(packet, 3); 967 btstack_linked_list_iterator_init(&it, &l2cap_channels); 968 while (btstack_linked_list_iterator_has_next(&it)){ 969 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 970 if (channel->con_handle != handle) continue; 971 l2cap_emit_channel_closed(channel); 972 l2cap_stop_rtx(channel); 973 btstack_linked_list_iterator_remove(&it); 974 btstack_memory_l2cap_channel_free(channel); 975 } 976 break; 977 978 // Notify channel packet handler if they can send now 979 case HCI_EVENT_TRANSPORT_PACKET_SENT: 980 case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS: 981 l2cap_run(); // try sending signaling packets first 982 l2cap_notify_channel_can_send(); 983 break; 984 985 // HCI Connection Timeouts 986 case L2CAP_EVENT_TIMEOUT_CHECK: 987 handle = little_endian_read_16(packet, 2); 988 if (gap_get_connection_type(handle) != GAP_CONNECTION_ACL) break; 989 if (hci_authentication_active_for_handle(handle)) break; 990 hci_con_used = 0; 991 btstack_linked_list_iterator_init(&it, &l2cap_channels); 992 while (btstack_linked_list_iterator_has_next(&it)){ 993 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 994 if (channel->con_handle != handle) continue; 995 hci_con_used = 1; 996 break; 997 } 998 if (hci_con_used) break; 999 if (!hci_can_send_command_packet_now()) break; 1000 hci_send_cmd(&hci_disconnect, handle, 0x13); // remote closed connection 1001 break; 1002 1003 case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE: 1004 handle = little_endian_read_16(packet, 3); 1005 btstack_linked_list_iterator_init(&it, &l2cap_channels); 1006 while (btstack_linked_list_iterator_has_next(&it)){ 1007 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 1008 if (channel->con_handle != handle) continue; 1009 l2cap_handle_remote_supported_features_received(channel); 1010 break; 1011 } 1012 break; 1013 1014 case GAP_EVENT_SECURITY_LEVEL: 1015 handle = little_endian_read_16(packet, 2); 1016 log_info("l2cap - security level update"); 1017 btstack_linked_list_iterator_init(&it, &l2cap_channels); 1018 while (btstack_linked_list_iterator_has_next(&it)){ 1019 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 1020 if (channel->con_handle != handle) continue; 1021 1022 log_info("l2cap - state %u", channel->state); 1023 1024 gap_security_level_t actual_level = (gap_security_level_t) packet[4]; 1025 gap_security_level_t required_level = channel->required_security_level; 1026 1027 switch (channel->state){ 1028 case L2CAP_STATE_WAIT_INCOMING_SECURITY_LEVEL_UPDATE: 1029 if (actual_level >= required_level){ 1030 channel->state = L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT; 1031 l2cap_emit_connection_request(channel); 1032 } else { 1033 channel->reason = 0x0003; // security block 1034 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE; 1035 } 1036 break; 1037 1038 case L2CAP_STATE_WAIT_OUTGOING_SECURITY_LEVEL_UPDATE: 1039 if (actual_level >= required_level){ 1040 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST; 1041 } else { 1042 // disconnnect, authentication not good enough 1043 hci_disconnect_security_block(handle); 1044 } 1045 break; 1046 1047 default: 1048 break; 1049 } 1050 } 1051 break; 1052 1053 default: 1054 break; 1055 } 1056 1057 l2cap_run(); 1058 } 1059 1060 static void l2cap_handle_disconnect_request(l2cap_channel_t *channel, uint16_t identifier){ 1061 channel->remote_sig_id = identifier; 1062 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE; 1063 l2cap_run(); 1064 } 1065 1066 static void l2cap_register_signaling_response(hci_con_handle_t handle, uint8_t code, uint8_t sig_id, uint16_t data){ 1067 // Vol 3, Part A, 4.3: "The DCID and SCID fields shall be ignored when the result field indi- cates the connection was refused." 1068 if (signaling_responses_pending < NR_PENDING_SIGNALING_RESPONSES) { 1069 signaling_responses[signaling_responses_pending].handle = handle; 1070 signaling_responses[signaling_responses_pending].code = code; 1071 signaling_responses[signaling_responses_pending].sig_id = sig_id; 1072 signaling_responses[signaling_responses_pending].data = data; 1073 signaling_responses_pending++; 1074 l2cap_run(); 1075 } 1076 } 1077 1078 static void l2cap_handle_connection_request(hci_con_handle_t handle, uint8_t sig_id, uint16_t psm, uint16_t source_cid){ 1079 1080 // log_info("l2cap_handle_connection_request for handle %u, psm %u cid 0x%02x", handle, psm, source_cid); 1081 l2cap_service_t *service = l2cap_get_service(psm); 1082 if (!service) { 1083 // 0x0002 PSM not supported 1084 l2cap_register_signaling_response(handle, CONNECTION_REQUEST, sig_id, 0x0002); 1085 return; 1086 } 1087 1088 hci_connection_t * hci_connection = hci_connection_for_handle( handle ); 1089 if (!hci_connection) { 1090 // 1091 log_error("no hci_connection for handle %u", handle); 1092 return; 1093 } 1094 1095 // alloc structure 1096 // log_info("l2cap_handle_connection_request register channel"); 1097 l2cap_channel_t * channel = l2cap_create_channel_entry(service->packet_handler, hci_connection->address, BD_ADDR_TYPE_CLASSIC, 1098 psm, service->mtu, service->required_security_level); 1099 if (!channel){ 1100 // 0x0004 No resources available 1101 l2cap_register_signaling_response(handle, CONNECTION_REQUEST, sig_id, 0x0004); 1102 return; 1103 } 1104 1105 channel->con_handle = handle; 1106 channel->remote_cid = source_cid; 1107 channel->remote_sig_id = sig_id; 1108 1109 // limit local mtu to max acl packet length - l2cap header 1110 if (channel->local_mtu > l2cap_max_mtu()) { 1111 channel->local_mtu = l2cap_max_mtu(); 1112 } 1113 1114 // set initial state 1115 channel->state = L2CAP_STATE_WAIT_INCOMING_SECURITY_LEVEL_UPDATE; 1116 channel->state_var = L2CAP_CHANNEL_STATE_VAR_SEND_CONN_RESP_PEND; 1117 1118 // add to connections list 1119 btstack_linked_list_add(&l2cap_channels, (btstack_linked_item_t *) channel); 1120 1121 // assert security requirements 1122 gap_request_security_level(handle, channel->required_security_level); 1123 } 1124 1125 void l2cap_accept_connection(uint16_t local_cid){ 1126 log_info("L2CAP_ACCEPT_CONNECTION local_cid 0x%x", local_cid); 1127 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 1128 if (!channel) { 1129 log_error("l2cap_accept_connection called but local_cid 0x%x not found", local_cid); 1130 return; 1131 } 1132 1133 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_ACCEPT; 1134 1135 // process 1136 l2cap_run(); 1137 } 1138 1139 void l2cap_decline_connection(uint16_t local_cid, uint8_t reason){ 1140 log_info("L2CAP_DECLINE_CONNECTION local_cid 0x%x, reason %x", local_cid, reason); 1141 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid( local_cid); 1142 if (!channel) { 1143 log_error( "l2cap_decline_connection called but local_cid 0x%x not found", local_cid); 1144 return; 1145 } 1146 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE; 1147 channel->reason = reason; 1148 l2cap_run(); 1149 } 1150 1151 static void l2cap_signaling_handle_configure_request(l2cap_channel_t *channel, uint8_t *command){ 1152 1153 channel->remote_sig_id = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 1154 1155 uint16_t flags = little_endian_read_16(command, 6); 1156 if (flags & 1) { 1157 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT); 1158 } 1159 1160 // accept the other's configuration options 1161 uint16_t end_pos = 4 + little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET); 1162 uint16_t pos = 8; 1163 while (pos < end_pos){ 1164 uint8_t option_hint = command[pos] >> 7; 1165 uint8_t option_type = command[pos] & 0x7f; 1166 log_info("l2cap cid %u, hint %u, type %u", channel->local_cid, option_hint, option_type); 1167 pos++; 1168 uint8_t length = command[pos++]; 1169 // MTU { type(8): 1, len(8):2, MTU(16) } 1170 if (option_type == 1 && length == 2){ 1171 channel->remote_mtu = little_endian_read_16(command, pos); 1172 // log_info("l2cap cid 0x%02x, remote mtu %u", channel->local_cid, channel->remote_mtu); 1173 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU); 1174 } 1175 // Flush timeout { type(8):2, len(8): 2, Flush Timeout(16)} 1176 if (option_type == 2 && length == 2){ 1177 channel->flush_timeout = little_endian_read_16(command, pos); 1178 } 1179 // check for unknown options 1180 if (option_hint == 0 && (option_type == 0 || option_type >= 0x07)){ 1181 log_info("l2cap cid %u, unknown options", channel->local_cid); 1182 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_INVALID); 1183 } 1184 pos += length; 1185 } 1186 } 1187 1188 static int l2cap_channel_ready_for_open(l2cap_channel_t *channel){ 1189 // log_info("l2cap_channel_ready_for_open 0x%02x", channel->state_var); 1190 if ((channel->state_var & L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_RSP) == 0) return 0; 1191 if ((channel->state_var & L2CAP_CHANNEL_STATE_VAR_SENT_CONF_RSP) == 0) return 0; 1192 // addition check that fixes re-entrance issue causing l2cap event channel opened twice 1193 if (channel->state == L2CAP_STATE_OPEN) return 0; 1194 return 1; 1195 } 1196 1197 1198 static void l2cap_signaling_handler_channel(l2cap_channel_t *channel, uint8_t *command){ 1199 1200 uint8_t code = command[L2CAP_SIGNALING_COMMAND_CODE_OFFSET]; 1201 uint8_t identifier = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 1202 uint16_t result = 0; 1203 1204 log_info("L2CAP signaling handler code %u, state %u", code, channel->state); 1205 1206 // handle DISCONNECT REQUESTS seperately 1207 if (code == DISCONNECTION_REQUEST){ 1208 switch (channel->state){ 1209 case L2CAP_STATE_CONFIG: 1210 case L2CAP_STATE_OPEN: 1211 case L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST: 1212 case L2CAP_STATE_WAIT_DISCONNECT: 1213 l2cap_handle_disconnect_request(channel, identifier); 1214 break; 1215 1216 default: 1217 // ignore in other states 1218 break; 1219 } 1220 return; 1221 } 1222 1223 // @STATEMACHINE(l2cap) 1224 switch (channel->state) { 1225 1226 case L2CAP_STATE_WAIT_CONNECT_RSP: 1227 switch (code){ 1228 case CONNECTION_RESPONSE: 1229 l2cap_stop_rtx(channel); 1230 result = little_endian_read_16 (command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+4); 1231 switch (result) { 1232 case 0: 1233 // successful connection 1234 channel->remote_cid = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 1235 channel->state = L2CAP_STATE_CONFIG; 1236 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 1237 break; 1238 case 1: 1239 // connection pending. get some coffee, but start the ERTX 1240 l2cap_start_ertx(channel); 1241 break; 1242 default: 1243 // channel closed 1244 channel->state = L2CAP_STATE_CLOSED; 1245 // map l2cap connection response result to BTstack status enumeration 1246 l2cap_emit_channel_opened(channel, L2CAP_CONNECTION_RESPONSE_RESULT_SUCCESSFUL + result); 1247 1248 // drop link key if security block 1249 if (L2CAP_CONNECTION_RESPONSE_RESULT_SUCCESSFUL + result == L2CAP_CONNECTION_RESPONSE_RESULT_REFUSED_SECURITY){ 1250 gap_drop_link_key_for_bd_addr(channel->address); 1251 } 1252 1253 // discard channel 1254 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 1255 btstack_memory_l2cap_channel_free(channel); 1256 break; 1257 } 1258 break; 1259 1260 default: 1261 //@TODO: implement other signaling packets 1262 break; 1263 } 1264 break; 1265 1266 case L2CAP_STATE_CONFIG: 1267 result = little_endian_read_16 (command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+4); 1268 switch (code) { 1269 case CONFIGURE_REQUEST: 1270 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP); 1271 l2cap_signaling_handle_configure_request(channel, command); 1272 if (!(channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT)){ 1273 // only done if continuation not set 1274 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_REQ); 1275 } 1276 break; 1277 case CONFIGURE_RESPONSE: 1278 l2cap_stop_rtx(channel); 1279 switch (result){ 1280 case 0: // success 1281 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_RSP); 1282 break; 1283 case 4: // pending 1284 l2cap_start_ertx(channel); 1285 break; 1286 default: 1287 // retry on negative result 1288 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 1289 break; 1290 } 1291 break; 1292 default: 1293 break; 1294 } 1295 if (l2cap_channel_ready_for_open(channel)){ 1296 // for open: 1297 channel->state = L2CAP_STATE_OPEN; 1298 l2cap_emit_channel_opened(channel, 0); 1299 } 1300 break; 1301 1302 case L2CAP_STATE_WAIT_DISCONNECT: 1303 switch (code) { 1304 case DISCONNECTION_RESPONSE: 1305 l2cap_finialize_channel_close(channel); 1306 break; 1307 default: 1308 //@TODO: implement other signaling packets 1309 break; 1310 } 1311 break; 1312 1313 case L2CAP_STATE_CLOSED: 1314 // @TODO handle incoming requests 1315 break; 1316 1317 case L2CAP_STATE_OPEN: 1318 //@TODO: implement other signaling packets, e.g. re-configure 1319 break; 1320 default: 1321 break; 1322 } 1323 // log_info("new state %u", channel->state); 1324 } 1325 1326 1327 static void l2cap_signaling_handler_dispatch( hci_con_handle_t handle, uint8_t * command){ 1328 1329 // get code, signalind identifier and command len 1330 uint8_t code = command[L2CAP_SIGNALING_COMMAND_CODE_OFFSET]; 1331 uint8_t sig_id = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 1332 1333 // not for a particular channel, and not CONNECTION_REQUEST, ECHO_[REQUEST|RESPONSE], INFORMATION_REQUEST 1334 if (code < 1 || code == ECHO_RESPONSE || code > INFORMATION_REQUEST){ 1335 l2cap_register_signaling_response(handle, COMMAND_REJECT, sig_id, L2CAP_REJ_CMD_UNKNOWN); 1336 return; 1337 } 1338 1339 // general commands without an assigned channel 1340 switch(code) { 1341 1342 case CONNECTION_REQUEST: { 1343 uint16_t psm = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 1344 uint16_t source_cid = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+2); 1345 l2cap_handle_connection_request(handle, sig_id, psm, source_cid); 1346 return; 1347 } 1348 1349 case ECHO_REQUEST: 1350 l2cap_register_signaling_response(handle, code, sig_id, 0); 1351 return; 1352 1353 case INFORMATION_REQUEST: { 1354 uint16_t infoType = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 1355 l2cap_register_signaling_response(handle, code, sig_id, infoType); 1356 return; 1357 } 1358 1359 default: 1360 break; 1361 } 1362 1363 1364 // Get potential destination CID 1365 uint16_t dest_cid = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 1366 1367 // Find channel for this sig_id and connection handle 1368 btstack_linked_list_iterator_t it; 1369 btstack_linked_list_iterator_init(&it, &l2cap_channels); 1370 while (btstack_linked_list_iterator_has_next(&it)){ 1371 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 1372 if (channel->con_handle != handle) continue; 1373 if (code & 1) { 1374 // match odd commands (responses) by previous signaling identifier 1375 if (channel->local_sig_id == sig_id) { 1376 l2cap_signaling_handler_channel(channel, command); 1377 break; 1378 } 1379 } else { 1380 // match even commands (requests) by local channel id 1381 if (channel->local_cid == dest_cid) { 1382 l2cap_signaling_handler_channel(channel, command); 1383 break; 1384 } 1385 } 1386 } 1387 } 1388 1389 static void l2cap_acl_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size ){ 1390 1391 // Get Channel ID 1392 uint16_t channel_id = READ_L2CAP_CHANNEL_ID(packet); 1393 hci_con_handle_t handle = READ_ACL_CONNECTION_HANDLE(packet); 1394 1395 switch (channel_id) { 1396 1397 case L2CAP_CID_SIGNALING: { 1398 1399 uint16_t command_offset = 8; 1400 while (command_offset < size) { 1401 1402 // handle signaling commands 1403 l2cap_signaling_handler_dispatch(handle, &packet[command_offset]); 1404 1405 // increment command_offset 1406 command_offset += L2CAP_SIGNALING_COMMAND_DATA_OFFSET + little_endian_read_16(packet, command_offset + L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET); 1407 } 1408 break; 1409 } 1410 1411 case L2CAP_CID_ATTRIBUTE_PROTOCOL: 1412 if (fixed_channels[L2CAP_FIXED_CHANNEL_TABLE_INDEX_ATTRIBUTE_PROTOCOL].callback) { 1413 (*fixed_channels[L2CAP_FIXED_CHANNEL_TABLE_INDEX_ATTRIBUTE_PROTOCOL].callback)(ATT_DATA_PACKET, handle, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1414 } 1415 break; 1416 1417 case L2CAP_CID_SECURITY_MANAGER_PROTOCOL: 1418 if (fixed_channels[L2CAP_FIXED_CHANNEL_TABLE_INDEX_SECURITY_MANAGER_PROTOCOL].callback) { 1419 (*fixed_channels[L2CAP_FIXED_CHANNEL_TABLE_INDEX_SECURITY_MANAGER_PROTOCOL].callback)(SM_DATA_PACKET, handle, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1420 } 1421 break; 1422 1423 case L2CAP_CID_CONNECTIONLESS_CHANNEL: 1424 if (fixed_channels[L2CAP_FIXED_CHANNEL_TABLE_INDEX_CONNECTIONLESS_CHANNEL].callback) { 1425 (*fixed_channels[L2CAP_FIXED_CHANNEL_TABLE_INDEX_CONNECTIONLESS_CHANNEL].callback)(UCD_DATA_PACKET, handle, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1426 } 1427 break; 1428 1429 case L2CAP_CID_SIGNALING_LE: { 1430 switch (packet[8]){ 1431 case CONNECTION_PARAMETER_UPDATE_RESPONSE: { 1432 uint16_t result = little_endian_read_16(packet, 12); 1433 l2cap_emit_connection_parameter_update_response(handle, result); 1434 break; 1435 } 1436 case CONNECTION_PARAMETER_UPDATE_REQUEST: { 1437 uint8_t event[10]; 1438 event[0] = L2CAP_EVENT_CONNECTION_PARAMETER_UPDATE_REQUEST; 1439 event[1] = 8; 1440 memcpy(&event[2], &packet[12], 8); 1441 1442 hci_connection_t * connection = hci_connection_for_handle(handle); 1443 if (connection){ 1444 if (connection->role != HCI_ROLE_MASTER){ 1445 // reject command without notifying upper layer when not in master role 1446 uint8_t sig_id = packet[COMPLETE_L2CAP_HEADER + 1]; 1447 l2cap_register_signaling_response(handle, COMMAND_REJECT_LE, sig_id, L2CAP_REJ_CMD_UNKNOWN); 1448 break; 1449 } 1450 int update_parameter = 1; 1451 le_connection_parameter_range_t existing_range; 1452 gap_get_connection_parameter_range(&existing_range); 1453 uint16_t le_conn_interval_min = little_endian_read_16(packet,12); 1454 uint16_t le_conn_interval_max = little_endian_read_16(packet,14); 1455 uint16_t le_conn_latency = little_endian_read_16(packet,16); 1456 uint16_t le_supervision_timeout = little_endian_read_16(packet,18); 1457 1458 if (le_conn_interval_min < existing_range.le_conn_interval_min) update_parameter = 0; 1459 if (le_conn_interval_max > existing_range.le_conn_interval_max) update_parameter = 0; 1460 1461 if (le_conn_latency < existing_range.le_conn_latency_min) update_parameter = 0; 1462 if (le_conn_latency > existing_range.le_conn_latency_max) update_parameter = 0; 1463 1464 if (le_supervision_timeout < existing_range.le_supervision_timeout_min) update_parameter = 0; 1465 if (le_supervision_timeout > existing_range.le_supervision_timeout_max) update_parameter = 0; 1466 1467 if (update_parameter){ 1468 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_RESPONSE; 1469 connection->le_conn_interval_min = le_conn_interval_min; 1470 connection->le_conn_interval_max = le_conn_interval_max; 1471 connection->le_conn_latency = le_conn_latency; 1472 connection->le_supervision_timeout = le_supervision_timeout; 1473 } else { 1474 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_DENY; 1475 } 1476 connection->le_con_param_update_identifier = packet[COMPLETE_L2CAP_HEADER + 1]; 1477 } 1478 1479 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 1480 if (!l2cap_event_packet_handler) break; 1481 (*l2cap_event_packet_handler)( HCI_EVENT_PACKET, 0, event, sizeof(event)); 1482 break; 1483 } 1484 default: { 1485 uint8_t sig_id = packet[COMPLETE_L2CAP_HEADER + 1]; 1486 l2cap_register_signaling_response(handle, COMMAND_REJECT_LE, sig_id, L2CAP_REJ_CMD_UNKNOWN); 1487 break; 1488 } 1489 } 1490 break; 1491 } 1492 1493 default: { 1494 // Find channel for this channel_id and connection handle 1495 l2cap_channel_t * l2cap_channel = l2cap_get_channel_for_local_cid(channel_id); 1496 if (l2cap_channel) { 1497 l2cap_dispatch_to_channel(l2cap_channel, L2CAP_DATA_PACKET, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1498 } 1499 break; 1500 } 1501 } 1502 1503 l2cap_run(); 1504 } 1505 1506 // finalize closed channel - l2cap_handle_disconnect_request & DISCONNECTION_RESPONSE 1507 void l2cap_finialize_channel_close(l2cap_channel_t * channel){ 1508 channel->state = L2CAP_STATE_CLOSED; 1509 l2cap_emit_channel_closed(channel); 1510 // discard channel 1511 l2cap_stop_rtx(channel); 1512 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 1513 btstack_memory_l2cap_channel_free(channel); 1514 } 1515 1516 static l2cap_service_t * l2cap_get_service_internal(btstack_linked_list_t * services, uint16_t psm){ 1517 btstack_linked_list_iterator_t it; 1518 btstack_linked_list_iterator_init(&it, services); 1519 while (btstack_linked_list_iterator_has_next(&it)){ 1520 l2cap_service_t * service = (l2cap_service_t *) btstack_linked_list_iterator_next(&it); 1521 if ( service->psm == psm){ 1522 return service; 1523 }; 1524 } 1525 return NULL; 1526 } 1527 1528 static inline l2cap_service_t * l2cap_get_service(uint16_t psm){ 1529 return l2cap_get_service_internal(&l2cap_services, psm); 1530 } 1531 1532 1533 uint8_t l2cap_register_service(btstack_packet_handler_t service_packet_handler, uint16_t psm, uint16_t mtu, gap_security_level_t security_level){ 1534 1535 log_info("L2CAP_REGISTER_SERVICE psm 0x%x mtu %u", psm, mtu); 1536 1537 // check for alread registered psm 1538 l2cap_service_t *service = l2cap_get_service(psm); 1539 if (service) { 1540 log_error("l2cap_register_service: PSM %u already registered", psm); 1541 return L2CAP_SERVICE_ALREADY_REGISTERED; 1542 } 1543 1544 // alloc structure 1545 service = btstack_memory_l2cap_service_get(); 1546 if (!service) { 1547 log_error("l2cap_register_service: no memory for l2cap_service_t"); 1548 return BTSTACK_MEMORY_ALLOC_FAILED; 1549 } 1550 1551 // fill in 1552 service->psm = psm; 1553 service->mtu = mtu; 1554 service->packet_handler = service_packet_handler; 1555 service->required_security_level = security_level; 1556 1557 // add to services list 1558 btstack_linked_list_add(&l2cap_services, (btstack_linked_item_t *) service); 1559 1560 // enable page scan 1561 gap_connectable_control(1); 1562 1563 return 0; 1564 } 1565 1566 void l2cap_unregister_service(uint16_t psm){ 1567 1568 log_info("L2CAP_UNREGISTER_SERVICE psm 0x%x", psm); 1569 1570 l2cap_service_t *service = l2cap_get_service(psm); 1571 if (!service) return; 1572 btstack_linked_list_remove(&l2cap_services, (btstack_linked_item_t *) service); 1573 btstack_memory_l2cap_service_free(service); 1574 1575 // disable page scan when no services registered 1576 if (!btstack_linked_list_empty(&l2cap_services)) return; 1577 gap_connectable_control(0); 1578 } 1579 1580 // Bluetooth 4.0 - allows to register handler for Attribute Protocol and Security Manager Protocol 1581 void l2cap_register_fixed_channel(btstack_packet_handler_t the_packet_handler, uint16_t channel_id) { 1582 int index = l2cap_fixed_channel_table_index_for_channel_id(channel_id); 1583 if (index < 0) return; 1584 fixed_channels[index].callback = the_packet_handler; 1585 } 1586 1587 #ifdef ENABLE_BLE 1588 1589 static inline l2cap_service_t * l2cap_le_get_service(uint16_t psm){ 1590 return l2cap_get_service_internal(&l2cap_le_services, psm); 1591 } 1592 /** 1593 * @brief Regster L2CAP LE Credit Based Flow Control Mode service 1594 * @param 1595 */ 1596 uint8_t l2cap_le_register_service(btstack_packet_handler_t packet_handler, uint16_t psm, gap_security_level_t security_level){ 1597 1598 log_info("L2CAP_LE_REGISTER_SERVICE psm 0x%x", psm); 1599 1600 // check for alread registered psm 1601 l2cap_service_t *service = l2cap_le_get_service(psm); 1602 if (service) { 1603 return L2CAP_SERVICE_ALREADY_REGISTERED; 1604 } 1605 1606 // alloc structure 1607 service = btstack_memory_l2cap_service_get(); 1608 if (!service) { 1609 log_error("l2cap_register_service_internal: no memory for l2cap_service_t"); 1610 return BTSTACK_MEMORY_ALLOC_FAILED; 1611 } 1612 1613 // fill in 1614 service->psm = psm; 1615 service->mtu = 0; 1616 service->packet_handler = packet_handler; 1617 service->required_security_level = security_level; 1618 1619 // add to services list 1620 btstack_linked_list_add(&l2cap_le_services, (btstack_linked_item_t *) service); 1621 1622 // done 1623 return 0; 1624 } 1625 1626 uint8_t l2cap_le_unregister_service(uint16_t psm) { 1627 log_info("L2CAP_LE_UNREGISTER_SERVICE psm 0x%x", psm); 1628 l2cap_service_t *service = l2cap_le_get_service(psm); 1629 if (!service) return L2CAP_SERVICE_NOT_FOUND; 1630 1631 btstack_linked_list_remove(&l2cap_le_services, (btstack_linked_item_t *) service); 1632 btstack_memory_l2cap_service_free(service); 1633 return 0; 1634 } 1635 1636 /* 1637 * @brief Accept incoming LE Data Channel connection 1638 * @param local_cid L2CAP LE Data Channel Identifier 1639 * @param receive_buffer buffer used for reassembly of L2CAP LE Information Frames into service data unit (SDU) with given MTU 1640 * @param receive_buffer_size buffer size equals MTU 1641 * @param initial_credits Number of initial credits provided to peer 1642 */ 1643 1644 uint8_t l2cap_le_accept_connection(uint16_t local_cid, uint8_t * receive_sdu_buffer, uint16_t mtu, uint16_t initial_credits){ 1645 return 0; 1646 } 1647 1648 /** 1649 * @brief Deny incoming LE Data Channel connection due to resource constraints 1650 * @param local_cid L2CAP LE Data Channel Identifier 1651 */ 1652 1653 uint8_t l2cap_le_decline_connection(uint16_t local_cid){ 1654 return 0; 1655 } 1656 1657 /** 1658 * @brief Create LE Data Channel 1659 * @param packet_handler Packet handler for this connection 1660 * @param address Peer address 1661 * @param address_type Peer address type 1662 * @param psm Service PSM to connect to 1663 * @param receive_buffer buffer used for reassembly of L2CAP LE Information Frames into service data unit (SDU) with given MTU 1664 * @param receive_buffer_size buffer size equals MTU 1665 * @param initial_credits Number of initial credits provided to peer 1666 * @param security_level Minimum required security level 1667 * @param out_local_cid L2CAP LE Channel Identifier is stored here 1668 */ 1669 uint8_t l2cap_le_create_channel(btstack_packet_handler_t packet_handler, bd_addr_t address, bd_addr_type_t address_type, 1670 uint16_t psm, uint8_t * receive_sdu_buffer, uint16_t mtu, uint16_t initial_credits, gap_security_level_t security_level, 1671 uint16_t * out_local_cid) 1672 { 1673 log_info("L2CAP_LE_CREATE_CHANNEL addr %s psm 0x%x mtu %u", bd_addr_to_str(address), psm, mtu); 1674 1675 l2cap_channel_t * channel = l2cap_create_channel_entry(packet_handler, address, BD_ADDR_TYPE_CLASSIC, psm, mtu, LEVEL_0); 1676 if (!channel) { 1677 return BTSTACK_MEMORY_ALLOC_FAILED; 1678 } 1679 1680 // add to connections list 1681 btstack_linked_list_add(&l2cap_le_channels, (btstack_linked_item_t *) channel); 1682 1683 // store local_cid 1684 if (out_local_cid){ 1685 *out_local_cid = channel->local_cid; 1686 } 1687 1688 // check if hci connection is already usable 1689 hci_connection_t * conn = hci_connection_for_bd_addr_and_type(address, address_type); 1690 if (conn){ 1691 log_info("l2cap_le_create_channel, hci connection already exists"); 1692 // l2cap_handle_connection_complete(conn->con_handle, channel); 1693 // check if remote supported fearures are already received 1694 // if (conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) { 1695 // l2cap_handle_remote_supported_features_received(channel); 1696 // } 1697 } 1698 1699 l2cap_run(); 1700 1701 return 0; 1702 } 1703 1704 /** 1705 * @brief Provide credtis for LE Data Channel 1706 * @param local_cid L2CAP LE Data Channel Identifier 1707 * @param credits Number additional credits for peer 1708 */ 1709 uint8_t l2cap_le_provide_credits(uint16_t cid, uint16_t credits){ 1710 return 0; 1711 } 1712 1713 /** 1714 * @brief Check if outgoing buffer is available and that there's space on the Bluetooth module 1715 * @param local_cid L2CAP LE Data Channel Identifier 1716 */ 1717 int l2cap_le_can_send_now(uint16_t cid){ 1718 return 0; 1719 } 1720 1721 /** 1722 * @brief Request emission of L2CAP_EVENT_CAN_SEND_NOW as soon as possible 1723 * @note L2CAP_EVENT_CAN_SEND_NOW might be emitted during call to this function 1724 * so packet handler should be ready to handle it 1725 * @param local_cid L2CAP LE Data Channel Identifier 1726 */ 1727 uint8_t l2cap_le_request_can_send_now_event(uint16_t cid){ 1728 return 0; 1729 } 1730 1731 /** 1732 * @brief Send data via LE Data Channel 1733 * @note Since data larger then the maximum PDU needs to be segmented into multiple PDUs, data needs to stay valid until ... event 1734 * @param local_cid L2CAP LE Data Channel Identifier 1735 * @param data data to send 1736 * @param size data size 1737 */ 1738 uint8_t l2cap_le_send_data(uint16_t cid, uint8_t * data, uint16_t size){ 1739 return 0; 1740 } 1741 1742 /** 1743 * @brief Disconnect from LE Data Channel 1744 * @param local_cid L2CAP LE Data Channel Identifier 1745 */ 1746 uint8_t l2cap_le_disconnect(uint16_t cid) 1747 { 1748 return 0; 1749 } 1750 1751 #endif 1752