1 /* 2 * Copyright (C) 2009-2012 by Matthias Ringwald 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 4. Any redistribution, use, or modification is done solely for 17 * personal benefit and not for any commercial purpose or for 18 * monetary gain. 19 * 20 * THIS SOFTWARE IS PROVIDED BY MATTHIAS RINGWALD AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS 24 * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Please inquire about commercial licensing options at [email protected] 34 * 35 */ 36 37 /* 38 * l2cap.c 39 * 40 * Logical Link Control and Adaption Protocl (L2CAP) 41 * 42 * Created by Matthias Ringwald on 5/16/09. 43 */ 44 45 #include "l2cap.h" 46 #include "hci.h" 47 #include "hci_dump.h" 48 #include "debug.h" 49 #include "btstack_memory.h" 50 51 #include <stdarg.h> 52 #include <string.h> 53 54 #include <stdio.h> 55 56 // nr of buffered acl packets in outgoing queue to get max performance 57 #define NR_BUFFERED_ACL_PACKETS 3 58 59 // used to cache l2cap rejects, echo, and informational requests 60 #define NR_PENDING_SIGNALING_RESPONSES 3 61 62 // offsets for L2CAP SIGNALING COMMANDS 63 #define L2CAP_SIGNALING_COMMAND_CODE_OFFSET 0 64 #define L2CAP_SIGNALING_COMMAND_SIGID_OFFSET 1 65 #define L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET 2 66 #define L2CAP_SIGNALING_COMMAND_DATA_OFFSET 4 67 68 static void null_packet_handler(void * connection, uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size); 69 static void l2cap_packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size); 70 71 // used to cache l2cap rejects, echo, and informational requests 72 static l2cap_signaling_response_t signaling_responses[NR_PENDING_SIGNALING_RESPONSES]; 73 static int signaling_responses_pending; 74 75 static linked_list_t l2cap_channels = NULL; 76 static linked_list_t l2cap_services = NULL; 77 static void (*packet_handler) (void * connection, uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size) = null_packet_handler; 78 static int new_credits_blocked = 0; 79 80 static btstack_packet_handler_t attribute_protocol_packet_handler = NULL; 81 static btstack_packet_handler_t security_protocol_packet_handler = NULL; 82 83 // prototypes 84 static void l2cap_finialize_channel_close(l2cap_channel_t *channel); 85 static l2cap_service_t * l2cap_get_service(uint16_t psm); 86 static void l2cap_emit_channel_opened(l2cap_channel_t *channel, uint8_t status); 87 static void l2cap_emit_channel_closed(l2cap_channel_t *channel); 88 static void l2cap_emit_connection_request(l2cap_channel_t *channel); 89 static int l2cap_channel_ready_for_open(l2cap_channel_t *channel); 90 91 92 void l2cap_init(){ 93 new_credits_blocked = 0; 94 signaling_responses_pending = 0; 95 96 l2cap_channels = NULL; 97 l2cap_services = NULL; 98 99 packet_handler = null_packet_handler; 100 101 // 102 // register callback with HCI 103 // 104 hci_register_packet_handler(&l2cap_packet_handler); 105 hci_connectable_control(0); // no services yet 106 } 107 108 109 /** Register L2CAP packet handlers */ 110 static void null_packet_handler(void * connection, uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 111 } 112 void l2cap_register_packet_handler(void (*handler)(void * connection, uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size)){ 113 packet_handler = handler; 114 } 115 116 // notify client/protocol handler 117 void l2cap_dispatch(l2cap_channel_t *channel, uint8_t type, uint8_t * data, uint16_t size){ 118 if (channel->packet_handler) { 119 (* (channel->packet_handler))(type, channel->local_cid, data, size); 120 } else { 121 (*packet_handler)(channel->connection, type, channel->local_cid, data, size); 122 } 123 } 124 125 void l2cap_emit_channel_opened(l2cap_channel_t *channel, uint8_t status) { 126 log_info("L2CAP_EVENT_CHANNEL_OPENED status 0x%x addr %s handle 0x%x psm 0x%x local_cid 0x%x remote_cid 0x%x local_mtu %u, remote_mtu %u", 127 status, bd_addr_to_str(channel->address), channel->handle, channel->psm, 128 channel->local_cid, channel->remote_cid, channel->local_mtu, channel->remote_mtu); 129 uint8_t event[21]; 130 event[0] = L2CAP_EVENT_CHANNEL_OPENED; 131 event[1] = sizeof(event) - 2; 132 event[2] = status; 133 bt_flip_addr(&event[3], channel->address); 134 bt_store_16(event, 9, channel->handle); 135 bt_store_16(event, 11, channel->psm); 136 bt_store_16(event, 13, channel->local_cid); 137 bt_store_16(event, 15, channel->remote_cid); 138 bt_store_16(event, 17, channel->local_mtu); 139 bt_store_16(event, 19, channel->remote_mtu); 140 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 141 l2cap_dispatch(channel, HCI_EVENT_PACKET, event, sizeof(event)); 142 } 143 144 void l2cap_emit_channel_closed(l2cap_channel_t *channel) { 145 log_info("L2CAP_EVENT_CHANNEL_CLOSED local_cid 0x%x", channel->local_cid); 146 uint8_t event[4]; 147 event[0] = L2CAP_EVENT_CHANNEL_CLOSED; 148 event[1] = sizeof(event) - 2; 149 bt_store_16(event, 2, channel->local_cid); 150 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 151 l2cap_dispatch(channel, HCI_EVENT_PACKET, event, sizeof(event)); 152 } 153 154 void l2cap_emit_connection_request(l2cap_channel_t *channel) { 155 log_info("L2CAP_EVENT_INCOMING_CONNECTION addr %s handle 0x%x psm 0x%x local_cid 0x%x remote_cid 0x%x", 156 bd_addr_to_str(channel->address), channel->handle, channel->psm, channel->local_cid, channel->remote_cid); 157 uint8_t event[16]; 158 event[0] = L2CAP_EVENT_INCOMING_CONNECTION; 159 event[1] = sizeof(event) - 2; 160 bt_flip_addr(&event[2], channel->address); 161 bt_store_16(event, 8, channel->handle); 162 bt_store_16(event, 10, channel->psm); 163 bt_store_16(event, 12, channel->local_cid); 164 bt_store_16(event, 14, channel->remote_cid); 165 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 166 l2cap_dispatch(channel, HCI_EVENT_PACKET, event, sizeof(event)); 167 } 168 169 static void l2cap_emit_service_registered(void *connection, uint8_t status, uint16_t psm){ 170 log_info("L2CAP_EVENT_SERVICE_REGISTERED status 0x%x psm 0x%x", status, psm); 171 uint8_t event[5]; 172 event[0] = L2CAP_EVENT_SERVICE_REGISTERED; 173 event[1] = sizeof(event) - 2; 174 event[2] = status; 175 bt_store_16(event, 3, psm); 176 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 177 (*packet_handler)(connection, HCI_EVENT_PACKET, 0, event, sizeof(event)); 178 } 179 180 void l2cap_emit_credits(l2cap_channel_t *channel, uint8_t credits) { 181 182 log_info("L2CAP_EVENT_CREDITS local_cid 0x%x credits %u", channel->local_cid, credits); 183 // track credits 184 channel->packets_granted += credits; 185 186 uint8_t event[5]; 187 event[0] = L2CAP_EVENT_CREDITS; 188 event[1] = sizeof(event) - 2; 189 bt_store_16(event, 2, channel->local_cid); 190 event[4] = credits; 191 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 192 l2cap_dispatch(channel, HCI_EVENT_PACKET, event, sizeof(event)); 193 } 194 195 void l2cap_block_new_credits(uint8_t blocked){ 196 new_credits_blocked = blocked; 197 } 198 199 void l2cap_hand_out_credits(void){ 200 201 if (new_credits_blocked) return; // we're told not to. used by daemon 202 203 linked_item_t *it; 204 for (it = (linked_item_t *) l2cap_channels; it ; it = it->next){ 205 if (!hci_number_free_acl_slots()) return; 206 l2cap_channel_t * channel = (l2cap_channel_t *) it; 207 if (channel->state != L2CAP_STATE_OPEN) continue; 208 if (hci_number_outgoing_packets(channel->handle) < NR_BUFFERED_ACL_PACKETS && channel->packets_granted == 0) { 209 l2cap_emit_credits(channel, 1); 210 } 211 } 212 } 213 214 l2cap_channel_t * l2cap_get_channel_for_local_cid(uint16_t local_cid){ 215 linked_item_t *it; 216 for (it = (linked_item_t *) l2cap_channels; it ; it = it->next){ 217 l2cap_channel_t * channel = (l2cap_channel_t *) it; 218 if ( channel->local_cid == local_cid) { 219 return channel; 220 } 221 } 222 return NULL; 223 } 224 225 int l2cap_can_send_packet_now(uint16_t local_cid){ 226 l2cap_channel_t *channel = l2cap_get_channel_for_local_cid(local_cid); 227 if (!channel) return 0; 228 if (!channel->packets_granted) return 0; 229 return hci_can_send_packet_now(HCI_ACL_DATA_PACKET); 230 } 231 232 uint16_t l2cap_get_remote_mtu_for_local_cid(uint16_t local_cid){ 233 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 234 if (channel) { 235 return channel->remote_mtu; 236 } 237 return 0; 238 } 239 240 int l2cap_send_signaling_packet(hci_con_handle_t handle, L2CAP_SIGNALING_COMMANDS cmd, uint8_t identifier, ...){ 241 242 if (!hci_can_send_packet_now(HCI_ACL_DATA_PACKET)){ 243 log_info("l2cap_send_signaling_packet, cannot send\n"); 244 return BTSTACK_ACL_BUFFERS_FULL; 245 } 246 247 // log_info("l2cap_send_signaling_packet type %u\n", cmd); 248 uint8_t *acl_buffer = hci_get_outgoing_acl_packet_buffer(); 249 va_list argptr; 250 va_start(argptr, identifier); 251 uint16_t len = l2cap_create_signaling_internal(acl_buffer, handle, cmd, identifier, argptr); 252 va_end(argptr); 253 // log_info("l2cap_send_signaling_packet con %u!\n", handle); 254 return hci_send_acl_packet(acl_buffer, len); 255 } 256 257 uint8_t *l2cap_get_outgoing_buffer(void){ 258 return hci_get_outgoing_acl_packet_buffer() + COMPLETE_L2CAP_HEADER; // 8 bytes 259 } 260 261 int l2cap_send_prepared(uint16_t local_cid, uint16_t len){ 262 263 if (!hci_can_send_packet_now(HCI_ACL_DATA_PACKET)){ 264 log_info("l2cap_send_internal cid 0x%02x, cannot send\n", local_cid); 265 return BTSTACK_ACL_BUFFERS_FULL; 266 } 267 268 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 269 if (!channel) { 270 log_error("l2cap_send_internal no channel for cid 0x%02x\n", local_cid); 271 return -1; // TODO: define error 272 } 273 274 if (channel->packets_granted == 0){ 275 log_error("l2cap_send_internal cid 0x%02x, no credits!\n", local_cid); 276 return -1; // TODO: define error 277 } 278 279 --channel->packets_granted; 280 281 log_debug("l2cap_send_internal cid 0x%02x, handle %u, 1 credit used, credits left %u;\n", 282 local_cid, channel->handle, channel->packets_granted); 283 284 uint8_t *acl_buffer = hci_get_outgoing_acl_packet_buffer(); 285 286 // 0 - Connection handle : PB=10 : BC=00 287 bt_store_16(acl_buffer, 0, channel->handle | (2 << 12) | (0 << 14)); 288 // 2 - ACL length 289 bt_store_16(acl_buffer, 2, len + 4); 290 // 4 - L2CAP packet length 291 bt_store_16(acl_buffer, 4, len + 0); 292 // 6 - L2CAP channel DEST 293 bt_store_16(acl_buffer, 6, channel->remote_cid); 294 // send 295 int err = hci_send_acl_packet(acl_buffer, len+8); 296 297 l2cap_hand_out_credits(); 298 299 return err; 300 } 301 302 int l2cap_send_prepared_connectionless(uint16_t handle, uint16_t cid, uint16_t len){ 303 304 if (!hci_can_send_packet_now(HCI_ACL_DATA_PACKET)){ 305 log_info("l2cap_send_prepared_to_handle cid 0x%02x, cannot send\n", cid); 306 return BTSTACK_ACL_BUFFERS_FULL; 307 } 308 309 log_debug("l2cap_send_prepared_to_handle cid 0x%02x, handle %u\n", cid, handle); 310 311 uint8_t *acl_buffer = hci_get_outgoing_acl_packet_buffer(); 312 313 // 0 - Connection handle : PB=10 : BC=00 314 bt_store_16(acl_buffer, 0, handle | (2 << 12) | (0 << 14)); 315 // 2 - ACL length 316 bt_store_16(acl_buffer, 2, len + 4); 317 // 4 - L2CAP packet length 318 bt_store_16(acl_buffer, 4, len + 0); 319 // 6 - L2CAP channel DEST 320 bt_store_16(acl_buffer, 6, cid); 321 // send 322 int err = hci_send_acl_packet(acl_buffer, len+8); 323 324 l2cap_hand_out_credits(); 325 326 return err; 327 } 328 329 int l2cap_send_internal(uint16_t local_cid, uint8_t *data, uint16_t len){ 330 331 if (!hci_can_send_packet_now(HCI_ACL_DATA_PACKET)){ 332 log_info("l2cap_send_internal cid 0x%02x, cannot send\n", local_cid); 333 return BTSTACK_ACL_BUFFERS_FULL; 334 } 335 336 uint8_t *acl_buffer = hci_get_outgoing_acl_packet_buffer(); 337 338 memcpy(&acl_buffer[8], data, len); 339 340 return l2cap_send_prepared(local_cid, len); 341 } 342 343 int l2cap_send_connectionless(uint16_t handle, uint16_t cid, uint8_t *data, uint16_t len){ 344 345 if (!hci_can_send_packet_now(HCI_ACL_DATA_PACKET)){ 346 log_info("l2cap_send_internal cid 0x%02x, cannot send\n", cid); 347 return BTSTACK_ACL_BUFFERS_FULL; 348 } 349 350 uint8_t *acl_buffer = hci_get_outgoing_acl_packet_buffer(); 351 352 memcpy(&acl_buffer[8], data, len); 353 354 return l2cap_send_prepared_connectionless(handle, cid, len); 355 } 356 357 static inline void channelStateVarSetFlag(l2cap_channel_t *channel, L2CAP_CHANNEL_STATE_VAR flag){ 358 channel->state_var = (L2CAP_CHANNEL_STATE_VAR) (channel->state_var | flag); 359 } 360 361 static inline void channelStateVarClearFlag(l2cap_channel_t *channel, L2CAP_CHANNEL_STATE_VAR flag){ 362 channel->state_var = (L2CAP_CHANNEL_STATE_VAR) (channel->state_var & ~flag); 363 } 364 365 366 367 // MARK: L2CAP_RUN 368 // process outstanding signaling tasks 369 void l2cap_run(void){ 370 371 // check pending signaling responses 372 while (signaling_responses_pending){ 373 374 if (!hci_can_send_packet_now(HCI_ACL_DATA_PACKET)) break; 375 376 hci_con_handle_t handle = signaling_responses[0].handle; 377 uint8_t sig_id = signaling_responses[0].sig_id; 378 uint16_t infoType = signaling_responses[0].data; // INFORMATION_REQUEST 379 uint16_t result = signaling_responses[0].data; // CONNECTION_REQUEST, COMMAND_REJECT 380 381 switch (signaling_responses[0].code){ 382 case CONNECTION_REQUEST: 383 l2cap_send_signaling_packet(handle, CONNECTION_RESPONSE, sig_id, 0, 0, result, 0); 384 break; 385 case ECHO_REQUEST: 386 l2cap_send_signaling_packet(handle, ECHO_RESPONSE, sig_id, 0, NULL); 387 break; 388 case INFORMATION_REQUEST: 389 if (infoType == 2) { 390 uint32_t features = 0; 391 // extended features request supported, however no features present 392 l2cap_send_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, infoType, 0, 4, &features); 393 } else { 394 // all other types are not supported 395 l2cap_send_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, infoType, 1, 0, NULL); 396 } 397 break; 398 case COMMAND_REJECT: 399 l2cap_send_signaling_packet(handle, COMMAND_REJECT, sig_id, result); 400 break; 401 default: 402 // should not happen 403 break; 404 } 405 406 // remove first item 407 signaling_responses_pending--; 408 int i; 409 for (i=0; i < signaling_responses_pending; i++){ 410 memcpy(&signaling_responses[i], &signaling_responses[i+1], sizeof(l2cap_signaling_response_t)); 411 } 412 } 413 414 uint8_t config_options[4]; 415 linked_item_t *it; 416 linked_item_t *next; 417 for (it = (linked_item_t *) l2cap_channels; it ; it = next){ 418 next = it->next; // cache next item as current item might get freed 419 420 if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) break; 421 if (!hci_can_send_packet_now(HCI_ACL_DATA_PACKET)) break; 422 423 l2cap_channel_t * channel = (l2cap_channel_t *) it; 424 425 // log_info("l2cap_run: state %u, var 0x%02x\n", channel->state, channel->state_var); 426 427 428 switch (channel->state){ 429 430 case L2CAP_STATE_WILL_SEND_CREATE_CONNECTION: 431 // send connection request - set state first 432 channel->state = L2CAP_STATE_WAIT_CONNECTION_COMPLETE; 433 // BD_ADDR, Packet_Type, Page_Scan_Repetition_Mode, Reserved, Clock_Offset, Allow_Role_Switch 434 hci_send_cmd(&hci_create_connection, channel->address, hci_usable_acl_packet_types(), 0, 0, 0, 1); 435 break; 436 437 case L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE: 438 l2cap_send_signaling_packet(channel->handle, CONNECTION_RESPONSE, channel->remote_sig_id, 0, 0, channel->reason, 0); 439 // discard channel - l2cap_finialize_channel_close without sending l2cap close event 440 linked_list_remove(&l2cap_channels, (linked_item_t *) channel); // -- remove from list 441 btstack_memory_l2cap_channel_free(channel); 442 break; 443 444 case L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_ACCEPT: 445 channel->state = L2CAP_STATE_CONFIG; 446 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 447 l2cap_send_signaling_packet(channel->handle, CONNECTION_RESPONSE, channel->remote_sig_id, channel->local_cid, channel->remote_cid, 0, 0); 448 break; 449 450 case L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST: 451 // success, start l2cap handshake 452 channel->local_sig_id = l2cap_next_sig_id(); 453 channel->state = L2CAP_STATE_WAIT_CONNECT_RSP; 454 l2cap_send_signaling_packet( channel->handle, CONNECTION_REQUEST, channel->local_sig_id, channel->psm, channel->local_cid); 455 break; 456 457 case L2CAP_STATE_CONFIG: 458 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP){ 459 uint16_t flags = 0; 460 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP); 461 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT) { 462 flags = 1; 463 } else { 464 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SENT_CONF_RSP); 465 } 466 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_INVALID){ 467 l2cap_send_signaling_packet(channel->handle, CONFIGURE_RESPONSE, channel->remote_sig_id, channel->remote_cid, flags, L2CAP_CONF_RESULT_UNKNOWN_OPTIONS, 0, NULL); 468 } else if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU){ 469 config_options[0] = 1; // MTU 470 config_options[1] = 2; // len param 471 bt_store_16( (uint8_t*)&config_options, 2, channel->remote_mtu); 472 l2cap_send_signaling_packet(channel->handle, CONFIGURE_RESPONSE, channel->remote_sig_id, channel->remote_cid, flags, 0, 4, &config_options); 473 channelStateVarClearFlag(channel,L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU); 474 } else { 475 l2cap_send_signaling_packet(channel->handle, CONFIGURE_RESPONSE, channel->remote_sig_id, channel->remote_cid, flags, 0, 0, NULL); 476 } 477 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT); 478 } 479 else if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ){ 480 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 481 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SENT_CONF_REQ); 482 channel->local_sig_id = l2cap_next_sig_id(); 483 config_options[0] = 1; // MTU 484 config_options[1] = 2; // len param 485 bt_store_16( (uint8_t*)&config_options, 2, channel->local_mtu); 486 l2cap_send_signaling_packet(channel->handle, CONFIGURE_REQUEST, channel->local_sig_id, channel->remote_cid, 0, 4, &config_options); 487 } 488 if (l2cap_channel_ready_for_open(channel)){ 489 channel->state = L2CAP_STATE_OPEN; 490 l2cap_emit_channel_opened(channel, 0); // success 491 l2cap_emit_credits(channel, 1); 492 } 493 break; 494 495 case L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE: 496 l2cap_send_signaling_packet( channel->handle, DISCONNECTION_RESPONSE, channel->remote_sig_id, channel->local_cid, channel->remote_cid); 497 l2cap_finialize_channel_close(channel); // -- remove from list 498 break; 499 500 case L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST: 501 channel->local_sig_id = l2cap_next_sig_id(); 502 channel->state = L2CAP_STATE_WAIT_DISCONNECT; 503 l2cap_send_signaling_packet( channel->handle, DISCONNECTION_REQUEST, channel->local_sig_id, channel->remote_cid, channel->local_cid); 504 break; 505 default: 506 break; 507 } 508 } 509 } 510 511 uint16_t l2cap_max_mtu(void){ 512 return hci_max_acl_data_packet_length() - L2CAP_HEADER_SIZE; 513 } 514 515 // open outgoing L2CAP channel 516 void l2cap_create_channel_internal(void * connection, btstack_packet_handler_t packet_handler, 517 bd_addr_t address, uint16_t psm, uint16_t mtu){ 518 519 log_info("L2CAP_CREATE_CHANNEL_MTU addr %s psm 0x%x mtu %u", bd_addr_to_str(address), psm, mtu); 520 521 // alloc structure 522 l2cap_channel_t * chan = (l2cap_channel_t*) btstack_memory_l2cap_channel_get(); 523 if (!chan) { 524 // emit error event 525 l2cap_channel_t dummy_channel; 526 BD_ADDR_COPY(dummy_channel.address, address); 527 dummy_channel.psm = psm; 528 l2cap_emit_channel_opened(&dummy_channel, BTSTACK_MEMORY_ALLOC_FAILED); 529 return; 530 } 531 // limit local mtu to max acl packet length 532 if (mtu > l2cap_max_mtu()) { 533 mtu = l2cap_max_mtu(); 534 } 535 536 // fill in 537 BD_ADDR_COPY(chan->address, address); 538 chan->psm = psm; 539 chan->handle = 0; 540 chan->connection = connection; 541 chan->packet_handler = packet_handler; 542 chan->remote_mtu = L2CAP_MINIMAL_MTU; 543 chan->local_mtu = mtu; 544 chan->packets_granted = 0; 545 546 // set initial state 547 chan->state = L2CAP_STATE_WILL_SEND_CREATE_CONNECTION; 548 chan->state_var = L2CAP_CHANNEL_STATE_VAR_NONE; 549 chan->remote_sig_id = L2CAP_SIG_ID_INVALID; 550 chan->local_sig_id = L2CAP_SIG_ID_INVALID; 551 552 // add to connections list 553 linked_list_add(&l2cap_channels, (linked_item_t *) chan); 554 555 l2cap_run(); 556 } 557 558 void l2cap_disconnect_internal(uint16_t local_cid, uint8_t reason){ 559 log_info("L2CAP_DISCONNECT local_cid 0x%x reason 0x%x", local_cid, reason); 560 // find channel for local_cid 561 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 562 if (channel) { 563 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST; 564 } 565 // process 566 l2cap_run(); 567 } 568 569 static void l2cap_handle_connection_failed_for_addr(bd_addr_t address, uint8_t status){ 570 linked_item_t *it = (linked_item_t *) &l2cap_channels; 571 while (it->next){ 572 l2cap_channel_t * channel = (l2cap_channel_t *) it->next; 573 if ( ! BD_ADDR_CMP( channel->address, address) ){ 574 if (channel->state == L2CAP_STATE_WAIT_CONNECTION_COMPLETE || channel->state == L2CAP_STATE_WILL_SEND_CREATE_CONNECTION) { 575 // failure, forward error code 576 l2cap_emit_channel_opened(channel, status); 577 // discard channel 578 it->next = it->next->next; 579 btstack_memory_l2cap_channel_free(channel); 580 } 581 } else { 582 it = it->next; 583 } 584 } 585 } 586 587 static void l2cap_handle_connection_success_for_addr(bd_addr_t address, hci_con_handle_t handle){ 588 linked_item_t *it; 589 for (it = (linked_item_t *) l2cap_channels; it ; it = it->next){ 590 l2cap_channel_t * channel = (l2cap_channel_t *) it; 591 if ( ! BD_ADDR_CMP( channel->address, address) ){ 592 if (channel->state == L2CAP_STATE_WAIT_CONNECTION_COMPLETE || channel->state == L2CAP_STATE_WILL_SEND_CREATE_CONNECTION) { 593 // success, start l2cap handshake 594 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST; 595 channel->handle = handle; 596 channel->local_cid = l2cap_next_local_cid(); 597 } 598 } 599 } 600 // process 601 l2cap_run(); 602 } 603 604 void l2cap_event_handler( uint8_t *packet, uint16_t size ){ 605 606 bd_addr_t address; 607 hci_con_handle_t handle; 608 l2cap_channel_t * channel; 609 linked_item_t *it; 610 int hci_con_used; 611 612 switch(packet[0]){ 613 614 // handle connection complete events 615 case HCI_EVENT_CONNECTION_COMPLETE: 616 bt_flip_addr(address, &packet[5]); 617 if (packet[2] == 0){ 618 handle = READ_BT_16(packet, 3); 619 l2cap_handle_connection_success_for_addr(address, handle); 620 } else { 621 l2cap_handle_connection_failed_for_addr(address, packet[2]); 622 } 623 break; 624 625 // handle successful create connection cancel command 626 case HCI_EVENT_COMMAND_COMPLETE: 627 if ( COMMAND_COMPLETE_EVENT(packet, hci_create_connection_cancel) ) { 628 if (packet[5] == 0){ 629 bt_flip_addr(address, &packet[6]); 630 // CONNECTION TERMINATED BY LOCAL HOST (0X16) 631 l2cap_handle_connection_failed_for_addr(address, 0x16); 632 } 633 } 634 l2cap_run(); // try sending signaling packets first 635 break; 636 637 case HCI_EVENT_COMMAND_STATUS: 638 l2cap_run(); // try sending signaling packets first 639 break; 640 641 // handle disconnection complete events 642 case HCI_EVENT_DISCONNECTION_COMPLETE: 643 // send l2cap disconnect events for all channels on this handle 644 handle = READ_BT_16(packet, 3); 645 it = (linked_item_t *) &l2cap_channels; 646 while (it->next){ 647 l2cap_channel_t * channel = (l2cap_channel_t *) it->next; 648 if ( channel->handle == handle ){ 649 // update prev item before free'ing next element - don't call l2cap_finalize_channel_close 650 it->next = it->next->next; 651 l2cap_emit_channel_closed(channel); 652 btstack_memory_l2cap_channel_free(channel); 653 } else { 654 it = it->next; 655 } 656 } 657 break; 658 659 case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS: 660 l2cap_run(); // try sending signaling packets first 661 l2cap_hand_out_credits(); 662 break; 663 664 // HCI Connection Timeouts 665 case L2CAP_EVENT_TIMEOUT_CHECK: 666 handle = READ_BT_16(packet, 2); 667 if (hci_authentication_active_for_handle(handle)) break; 668 hci_con_used = 0; 669 for (it = (linked_item_t *) l2cap_channels; it ; it = it->next){ 670 channel = (l2cap_channel_t *) it; 671 if (channel->handle == handle) { 672 hci_con_used = 1; 673 } 674 } 675 if (hci_con_used) break; 676 if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) break; 677 hci_send_cmd(&hci_disconnect, handle, 0x13); // remote closed connection 678 break; 679 680 case DAEMON_EVENT_HCI_PACKET_SENT: 681 for (it = (linked_item_t *) l2cap_channels; it ; it = it->next){ 682 channel = (l2cap_channel_t *) it; 683 if (channel->packet_handler) { 684 (* (channel->packet_handler))(HCI_EVENT_PACKET, channel->local_cid, packet, size); 685 } 686 } 687 if (attribute_protocol_packet_handler) { 688 (*attribute_protocol_packet_handler)(HCI_EVENT_PACKET, 0, packet, size); 689 } 690 if (security_protocol_packet_handler) { 691 (*security_protocol_packet_handler)(HCI_EVENT_PACKET, 0, packet, size); 692 } 693 break; 694 695 default: 696 break; 697 } 698 699 // pass on 700 (*packet_handler)(NULL, HCI_EVENT_PACKET, 0, packet, size); 701 } 702 703 static void l2cap_handle_disconnect_request(l2cap_channel_t *channel, uint16_t identifier){ 704 channel->remote_sig_id = identifier; 705 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE; 706 l2cap_run(); 707 } 708 709 static void l2cap_register_signaling_response(hci_con_handle_t handle, uint8_t code, uint8_t sig_id, uint16_t data){ 710 // Vol 3, Part A, 4.3: "The DCID and SCID fields shall be ignored when the result field indi- cates the connection was refused." 711 if (signaling_responses_pending < NR_PENDING_SIGNALING_RESPONSES) { 712 signaling_responses[signaling_responses_pending].handle = handle; 713 signaling_responses[signaling_responses_pending].code = code; 714 signaling_responses[signaling_responses_pending].sig_id = sig_id; 715 signaling_responses[signaling_responses_pending].data = data; 716 signaling_responses_pending++; 717 l2cap_run(); 718 } 719 } 720 721 static void l2cap_handle_connection_request(hci_con_handle_t handle, uint8_t sig_id, uint16_t psm, uint16_t source_cid){ 722 723 // log_info("l2cap_handle_connection_request for handle %u, psm %u cid 0x%02x\n", handle, psm, source_cid); 724 l2cap_service_t *service = l2cap_get_service(psm); 725 if (!service) { 726 // 0x0002 PSM not supported 727 l2cap_register_signaling_response(handle, CONNECTION_REQUEST, sig_id, 0x0002); 728 return; 729 } 730 731 hci_connection_t * hci_connection = hci_connection_for_handle( handle ); 732 if (!hci_connection) { 733 // 734 log_error("no hci_connection for handle %u\n", handle); 735 return; 736 } 737 // alloc structure 738 // log_info("l2cap_handle_connection_request register channel\n"); 739 l2cap_channel_t * channel = (l2cap_channel_t*) btstack_memory_l2cap_channel_get(); 740 if (!channel){ 741 // 0x0004 No resources available 742 l2cap_register_signaling_response(handle, CONNECTION_REQUEST, sig_id, 0x0004); 743 return; 744 } 745 746 // fill in 747 BD_ADDR_COPY(channel->address, hci_connection->address); 748 channel->psm = psm; 749 channel->handle = handle; 750 channel->connection = service->connection; 751 channel->packet_handler = service->packet_handler; 752 channel->local_cid = l2cap_next_local_cid(); 753 channel->remote_cid = source_cid; 754 channel->local_mtu = service->mtu; 755 channel->remote_mtu = L2CAP_DEFAULT_MTU; 756 channel->packets_granted = 0; 757 channel->remote_sig_id = sig_id; 758 759 // limit local mtu to max acl packet length 760 if (channel->local_mtu > l2cap_max_mtu()) { 761 channel->local_mtu = l2cap_max_mtu(); 762 } 763 764 // set initial state 765 channel->state = L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT; 766 channel->state_var = L2CAP_CHANNEL_STATE_VAR_NONE; 767 768 // add to connections list 769 linked_list_add(&l2cap_channels, (linked_item_t *) channel); 770 771 // emit incoming connection request 772 l2cap_emit_connection_request(channel); 773 } 774 775 void l2cap_accept_connection_internal(uint16_t local_cid){ 776 log_info("L2CAP_ACCEPT_CONNECTION local_cid 0x%x", local_cid); 777 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 778 if (!channel) { 779 log_error("l2cap_accept_connection_internal called but local_cid 0x%x not found", local_cid); 780 return; 781 } 782 783 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_ACCEPT; 784 785 // process 786 l2cap_run(); 787 } 788 789 void l2cap_decline_connection_internal(uint16_t local_cid, uint8_t reason){ 790 log_info("L2CAP_DECLINE_CONNECTION local_cid 0x%x, reason %x", local_cid, reason); 791 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid( local_cid); 792 if (!channel) { 793 log_error( "l2cap_decline_connection_internal called but local_cid 0x%x not found", local_cid); 794 return; 795 } 796 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE; 797 channel->reason = reason; 798 l2cap_run(); 799 } 800 801 void l2cap_signaling_handle_configure_request(l2cap_channel_t *channel, uint8_t *command){ 802 803 channel->remote_sig_id = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 804 805 uint16_t flags = READ_BT_16(command, 6); 806 if (flags & 1) { 807 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT); 808 } 809 810 // accept the other's configuration options 811 uint16_t end_pos = 4 + READ_BT_16(command, L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET); 812 uint16_t pos = 8; 813 while (pos < end_pos){ 814 uint8_t option_hint = command[pos] >> 7; 815 uint8_t option_type = command[pos] & 0x7f; 816 log_info("l2cap cid %u, hint %u, type %u", channel->local_cid, option_hint, option_type); 817 pos++; 818 uint8_t length = command[pos++]; 819 // MTU { type(8): 1, len(8):2, MTU(16) } 820 if (option_type == 1 && length == 2){ 821 channel->remote_mtu = READ_BT_16(command, pos); 822 // log_info("l2cap cid 0x%02x, remote mtu %u\n", channel->local_cid, channel->remote_mtu); 823 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU); 824 } 825 // check for unknown options 826 if (option_hint == 0 && (option_type == 0 || option_type >= 0x07)){ 827 log_info("l2cap cid %u, unknown options", channel->local_cid); 828 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_INVALID); 829 } 830 pos += length; 831 } 832 } 833 834 static int l2cap_channel_ready_for_open(l2cap_channel_t *channel){ 835 // log_info("l2cap_channel_ready_for_open 0x%02x\n", channel->state_var); 836 if ((channel->state_var & L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_RSP) == 0) return 0; 837 if ((channel->state_var & L2CAP_CHANNEL_STATE_VAR_SENT_CONF_RSP) == 0) return 0; 838 return 1; 839 } 840 841 842 void l2cap_signaling_handler_channel(l2cap_channel_t *channel, uint8_t *command){ 843 844 uint8_t code = command[L2CAP_SIGNALING_COMMAND_CODE_OFFSET]; 845 uint8_t identifier = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 846 uint16_t result = 0; 847 848 log_info("L2CAP signaling handler code %u, state %u\n", code, channel->state); 849 850 // handle DISCONNECT REQUESTS seperately 851 if (code == DISCONNECTION_REQUEST){ 852 switch (channel->state){ 853 case L2CAP_STATE_CONFIG: 854 case L2CAP_STATE_OPEN: 855 case L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST: 856 case L2CAP_STATE_WAIT_DISCONNECT: 857 l2cap_handle_disconnect_request(channel, identifier); 858 break; 859 860 default: 861 // ignore in other states 862 break; 863 } 864 return; 865 } 866 867 // @STATEMACHINE(l2cap) 868 switch (channel->state) { 869 870 case L2CAP_STATE_WAIT_CONNECT_RSP: 871 switch (code){ 872 case CONNECTION_RESPONSE: 873 result = READ_BT_16 (command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+4); 874 switch (result) { 875 case 0: 876 // successful connection 877 channel->remote_cid = READ_BT_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 878 channel->state = L2CAP_STATE_CONFIG; 879 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 880 break; 881 case 1: 882 // connection pending. get some coffee 883 break; 884 default: 885 // channel closed 886 channel->state = L2CAP_STATE_CLOSED; 887 888 // map l2cap connection response result to BTstack status enumeration 889 l2cap_emit_channel_opened(channel, L2CAP_CONNECTION_RESPONSE_RESULT_SUCCESSFUL + result); 890 891 // drop link key if security block 892 if (L2CAP_CONNECTION_RESPONSE_RESULT_SUCCESSFUL + result == L2CAP_CONNECTION_RESPONSE_RESULT_REFUSED_SECURITY){ 893 hci_drop_link_key_for_bd_addr(&channel->address); 894 } 895 896 // discard channel 897 linked_list_remove(&l2cap_channels, (linked_item_t *) channel); 898 btstack_memory_l2cap_channel_free(channel); 899 break; 900 } 901 break; 902 903 default: 904 //@TODO: implement other signaling packets 905 break; 906 } 907 break; 908 909 case L2CAP_STATE_CONFIG: 910 result = READ_BT_16 (command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+4); 911 switch (code) { 912 case CONFIGURE_REQUEST: 913 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP); 914 l2cap_signaling_handle_configure_request(channel, command); 915 if (!(channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT)){ 916 // only done if continuation not set 917 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_REQ); 918 } 919 break; 920 case CONFIGURE_RESPONSE: 921 if (result) { 922 // retry on negative result 923 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 924 break; 925 } 926 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_RSP); 927 break; 928 default: 929 break; 930 } 931 if (l2cap_channel_ready_for_open(channel)){ 932 // for open: 933 channel->state = L2CAP_STATE_OPEN; 934 l2cap_emit_channel_opened(channel, 0); 935 l2cap_emit_credits(channel, 1); 936 } 937 break; 938 939 case L2CAP_STATE_WAIT_DISCONNECT: 940 switch (code) { 941 case DISCONNECTION_RESPONSE: 942 l2cap_finialize_channel_close(channel); 943 break; 944 default: 945 //@TODO: implement other signaling packets 946 break; 947 } 948 break; 949 950 case L2CAP_STATE_CLOSED: 951 // @TODO handle incoming requests 952 break; 953 954 case L2CAP_STATE_OPEN: 955 //@TODO: implement other signaling packets, e.g. re-configure 956 break; 957 default: 958 break; 959 } 960 // log_info("new state %u\n", channel->state); 961 } 962 963 964 void l2cap_signaling_handler_dispatch( hci_con_handle_t handle, uint8_t * command){ 965 966 // get code, signalind identifier and command len 967 uint8_t code = command[L2CAP_SIGNALING_COMMAND_CODE_OFFSET]; 968 uint8_t sig_id = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 969 970 // not for a particular channel, and not CONNECTION_REQUEST, ECHO_[REQUEST|RESPONSE], INFORMATION_REQUEST 971 if (code < 1 || code == ECHO_RESPONSE || code > INFORMATION_REQUEST){ 972 l2cap_register_signaling_response(handle, COMMAND_REJECT, sig_id, L2CAP_REJ_CMD_UNKNOWN); 973 return; 974 } 975 976 // general commands without an assigned channel 977 switch(code) { 978 979 case CONNECTION_REQUEST: { 980 uint16_t psm = READ_BT_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 981 uint16_t source_cid = READ_BT_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+2); 982 l2cap_handle_connection_request(handle, sig_id, psm, source_cid); 983 return; 984 } 985 986 case ECHO_REQUEST: 987 l2cap_register_signaling_response(handle, code, sig_id, 0); 988 return; 989 990 case INFORMATION_REQUEST: { 991 uint16_t infoType = READ_BT_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 992 l2cap_register_signaling_response(handle, code, sig_id, infoType); 993 return; 994 } 995 996 default: 997 break; 998 } 999 1000 1001 // Get potential destination CID 1002 uint16_t dest_cid = READ_BT_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 1003 1004 // Find channel for this sig_id and connection handle 1005 linked_item_t *it; 1006 for (it = (linked_item_t *) l2cap_channels; it ; it = it->next){ 1007 l2cap_channel_t * channel = (l2cap_channel_t *) it; 1008 if (channel->handle == handle) { 1009 if (code & 1) { 1010 // match odd commands (responses) by previous signaling identifier 1011 if (channel->local_sig_id == sig_id) { 1012 l2cap_signaling_handler_channel(channel, command); 1013 break; 1014 } 1015 } else { 1016 // match even commands (requests) by local channel id 1017 if (channel->local_cid == dest_cid) { 1018 l2cap_signaling_handler_channel(channel, command); 1019 break; 1020 } 1021 } 1022 } 1023 } 1024 } 1025 1026 void l2cap_acl_handler( uint8_t *packet, uint16_t size ){ 1027 1028 // Get Channel ID 1029 uint16_t channel_id = READ_L2CAP_CHANNEL_ID(packet); 1030 hci_con_handle_t handle = READ_ACL_CONNECTION_HANDLE(packet); 1031 1032 switch (channel_id) { 1033 1034 case L2CAP_CID_SIGNALING: { 1035 1036 uint16_t command_offset = 8; 1037 while (command_offset < size) { 1038 1039 // handle signaling commands 1040 l2cap_signaling_handler_dispatch(handle, &packet[command_offset]); 1041 1042 // increment command_offset 1043 command_offset += L2CAP_SIGNALING_COMMAND_DATA_OFFSET + READ_BT_16(packet, command_offset + L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET); 1044 } 1045 break; 1046 } 1047 1048 case L2CAP_CID_ATTRIBUTE_PROTOCOL: 1049 if (attribute_protocol_packet_handler) { 1050 (*attribute_protocol_packet_handler)(ATT_DATA_PACKET, handle, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1051 } 1052 break; 1053 1054 case L2CAP_CID_SECURITY_MANAGER_PROTOCOL: 1055 if (security_protocol_packet_handler) { 1056 (*security_protocol_packet_handler)(SM_DATA_PACKET, handle, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1057 } 1058 break; 1059 1060 default: { 1061 // Find channel for this channel_id and connection handle 1062 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(channel_id); 1063 if (channel) { 1064 l2cap_dispatch(channel, L2CAP_DATA_PACKET, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1065 } 1066 break; 1067 } 1068 } 1069 1070 l2cap_run(); 1071 } 1072 1073 static void l2cap_packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){ 1074 switch (packet_type) { 1075 case HCI_EVENT_PACKET: 1076 l2cap_event_handler(packet, size); 1077 break; 1078 case HCI_ACL_DATA_PACKET: 1079 l2cap_acl_handler(packet, size); 1080 break; 1081 default: 1082 break; 1083 } 1084 } 1085 1086 // finalize closed channel - l2cap_handle_disconnect_request & DISCONNECTION_RESPONSE 1087 void l2cap_finialize_channel_close(l2cap_channel_t *channel){ 1088 channel->state = L2CAP_STATE_CLOSED; 1089 l2cap_emit_channel_closed(channel); 1090 // discard channel 1091 linked_list_remove(&l2cap_channels, (linked_item_t *) channel); 1092 btstack_memory_l2cap_channel_free(channel); 1093 } 1094 1095 l2cap_service_t * l2cap_get_service(uint16_t psm){ 1096 linked_item_t *it; 1097 1098 // close open channels 1099 for (it = (linked_item_t *) l2cap_services; it ; it = it->next){ 1100 l2cap_service_t * service = ((l2cap_service_t *) it); 1101 if ( service->psm == psm){ 1102 return service; 1103 }; 1104 } 1105 return NULL; 1106 } 1107 1108 void l2cap_register_service_internal(void *connection, btstack_packet_handler_t packet_handler, uint16_t psm, uint16_t mtu){ 1109 1110 log_info("L2CAP_REGISTER_SERVICE psm 0x%x mtu %u", psm, mtu); 1111 1112 // check for alread registered psm 1113 // TODO: emit error event 1114 l2cap_service_t *service = l2cap_get_service(psm); 1115 if (service) { 1116 log_error("l2cap_register_service_internal: PSM %u already registered\n", psm); 1117 l2cap_emit_service_registered(connection, L2CAP_SERVICE_ALREADY_REGISTERED, psm); 1118 return; 1119 } 1120 1121 // alloc structure 1122 // TODO: emit error event 1123 service = (l2cap_service_t *) btstack_memory_l2cap_service_get(); 1124 if (!service) { 1125 log_error("l2cap_register_service_internal: no memory for l2cap_service_t\n"); 1126 l2cap_emit_service_registered(connection, BTSTACK_MEMORY_ALLOC_FAILED, psm); 1127 return; 1128 } 1129 1130 // fill in 1131 service->psm = psm; 1132 service->mtu = mtu; 1133 service->connection = connection; 1134 service->packet_handler = packet_handler; 1135 1136 // add to services list 1137 linked_list_add(&l2cap_services, (linked_item_t *) service); 1138 1139 // enable page scan 1140 hci_connectable_control(1); 1141 1142 // done 1143 l2cap_emit_service_registered(connection, 0, psm); 1144 } 1145 1146 void l2cap_unregister_service_internal(void *connection, uint16_t psm){ 1147 1148 log_info("L2CAP_UNREGISTER_SERVICE psm 0x%x", psm); 1149 1150 l2cap_service_t *service = l2cap_get_service(psm); 1151 if (!service) return; 1152 linked_list_remove(&l2cap_services, (linked_item_t *) service); 1153 btstack_memory_l2cap_service_free(service); 1154 1155 // disable page scan when no services registered 1156 if (!linked_list_empty(&l2cap_services)) return; 1157 hci_connectable_control(0); 1158 } 1159 1160 // 1161 void l2cap_close_connection(void *connection){ 1162 linked_item_t *it; 1163 1164 // close open channels - note to myself: no channel is freed, so no new for fancy iterator tricks 1165 l2cap_channel_t * channel; 1166 for (it = (linked_item_t *) l2cap_channels; it ; it = it->next){ 1167 channel = (l2cap_channel_t *) it; 1168 if (channel->connection == connection) { 1169 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST; 1170 } 1171 } 1172 1173 // unregister services 1174 it = (linked_item_t *) &l2cap_services; 1175 while (it->next) { 1176 l2cap_service_t * service = (l2cap_service_t *) it->next; 1177 if (service->connection == connection){ 1178 it->next = it->next->next; 1179 btstack_memory_l2cap_service_free(service); 1180 } else { 1181 it = it->next; 1182 } 1183 } 1184 1185 // process 1186 l2cap_run(); 1187 } 1188 1189 // Bluetooth 4.0 - allows to register handler for Attribute Protocol and Security Manager Protocol 1190 void l2cap_register_fixed_channel(btstack_packet_handler_t packet_handler, uint16_t channel_id) { 1191 switch(channel_id){ 1192 case L2CAP_CID_ATTRIBUTE_PROTOCOL: 1193 attribute_protocol_packet_handler = packet_handler; 1194 break; 1195 case L2CAP_CID_SECURITY_MANAGER_PROTOCOL: 1196 security_protocol_packet_handler = packet_handler; 1197 break; 1198 } 1199 } 1200 1201