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 switch (infoType){ 390 case 1: { // Connectionless MTU 391 uint16_t connectionless_mtu = hci_max_acl_data_packet_length(); 392 l2cap_send_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, infoType, 0, sizeof(connectionless_mtu), &connectionless_mtu); 393 break; 394 } 395 case 2: { // Extended Features Supported 396 // extended features request supported, only supporing fixed channel map 397 uint32_t features = 0x80; 398 l2cap_send_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, infoType, 0, sizeof(features), &features); 399 break; 400 } 401 case 3: { // Fixed Channels Supported 402 uint8_t map[8]; 403 memset(map, 0, 8); 404 map[0] = 0x01; // L2CAP Signaling Channel 405 l2cap_send_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, infoType, 0, sizeof(map), &map); 406 break; 407 } 408 default: 409 // all other types are not supported 410 l2cap_send_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, infoType, 1, 0, NULL); 411 break; 412 } 413 break; 414 case COMMAND_REJECT: 415 l2cap_send_signaling_packet(handle, COMMAND_REJECT, sig_id, result); 416 break; 417 default: 418 // should not happen 419 break; 420 } 421 422 // remove first item 423 signaling_responses_pending--; 424 int i; 425 for (i=0; i < signaling_responses_pending; i++){ 426 memcpy(&signaling_responses[i], &signaling_responses[i+1], sizeof(l2cap_signaling_response_t)); 427 } 428 } 429 430 uint8_t config_options[4]; 431 linked_item_t *it; 432 linked_item_t *next; 433 for (it = (linked_item_t *) l2cap_channels; it ; it = next){ 434 next = it->next; // cache next item as current item might get freed 435 436 if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) break; 437 if (!hci_can_send_packet_now(HCI_ACL_DATA_PACKET)) break; 438 439 l2cap_channel_t * channel = (l2cap_channel_t *) it; 440 441 // log_info("l2cap_run: state %u, var 0x%02x\n", channel->state, channel->state_var); 442 443 444 switch (channel->state){ 445 446 case L2CAP_STATE_WILL_SEND_CREATE_CONNECTION: 447 // send connection request - set state first 448 channel->state = L2CAP_STATE_WAIT_CONNECTION_COMPLETE; 449 // BD_ADDR, Packet_Type, Page_Scan_Repetition_Mode, Reserved, Clock_Offset, Allow_Role_Switch 450 hci_send_cmd(&hci_create_connection, channel->address, hci_usable_acl_packet_types(), 0, 0, 0, 1); 451 break; 452 453 case L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE: 454 l2cap_send_signaling_packet(channel->handle, CONNECTION_RESPONSE, channel->remote_sig_id, 0, 0, channel->reason, 0); 455 // discard channel - l2cap_finialize_channel_close without sending l2cap close event 456 linked_list_remove(&l2cap_channels, (linked_item_t *) channel); // -- remove from list 457 btstack_memory_l2cap_channel_free(channel); 458 break; 459 460 case L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_ACCEPT: 461 channel->state = L2CAP_STATE_CONFIG; 462 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 463 l2cap_send_signaling_packet(channel->handle, CONNECTION_RESPONSE, channel->remote_sig_id, channel->local_cid, channel->remote_cid, 0, 0); 464 break; 465 466 case L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST: 467 // success, start l2cap handshake 468 channel->local_sig_id = l2cap_next_sig_id(); 469 channel->state = L2CAP_STATE_WAIT_CONNECT_RSP; 470 l2cap_send_signaling_packet( channel->handle, CONNECTION_REQUEST, channel->local_sig_id, channel->psm, channel->local_cid); 471 break; 472 473 case L2CAP_STATE_CONFIG: 474 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP){ 475 uint16_t flags = 0; 476 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP); 477 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT) { 478 flags = 1; 479 } else { 480 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SENT_CONF_RSP); 481 } 482 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_INVALID){ 483 l2cap_send_signaling_packet(channel->handle, CONFIGURE_RESPONSE, channel->remote_sig_id, channel->remote_cid, flags, L2CAP_CONF_RESULT_UNKNOWN_OPTIONS, 0, NULL); 484 } else if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU){ 485 config_options[0] = 1; // MTU 486 config_options[1] = 2; // len param 487 bt_store_16( (uint8_t*)&config_options, 2, channel->remote_mtu); 488 l2cap_send_signaling_packet(channel->handle, CONFIGURE_RESPONSE, channel->remote_sig_id, channel->remote_cid, flags, 0, 4, &config_options); 489 channelStateVarClearFlag(channel,L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU); 490 } else { 491 l2cap_send_signaling_packet(channel->handle, CONFIGURE_RESPONSE, channel->remote_sig_id, channel->remote_cid, flags, 0, 0, NULL); 492 } 493 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT); 494 } 495 else if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ){ 496 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 497 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SENT_CONF_REQ); 498 channel->local_sig_id = l2cap_next_sig_id(); 499 config_options[0] = 1; // MTU 500 config_options[1] = 2; // len param 501 bt_store_16( (uint8_t*)&config_options, 2, channel->local_mtu); 502 l2cap_send_signaling_packet(channel->handle, CONFIGURE_REQUEST, channel->local_sig_id, channel->remote_cid, 0, 4, &config_options); 503 } 504 if (l2cap_channel_ready_for_open(channel)){ 505 channel->state = L2CAP_STATE_OPEN; 506 l2cap_emit_channel_opened(channel, 0); // success 507 l2cap_emit_credits(channel, 1); 508 } 509 break; 510 511 case L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE: 512 l2cap_send_signaling_packet( channel->handle, DISCONNECTION_RESPONSE, channel->remote_sig_id, channel->local_cid, channel->remote_cid); 513 l2cap_finialize_channel_close(channel); // -- remove from list 514 break; 515 516 case L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST: 517 channel->local_sig_id = l2cap_next_sig_id(); 518 channel->state = L2CAP_STATE_WAIT_DISCONNECT; 519 l2cap_send_signaling_packet( channel->handle, DISCONNECTION_REQUEST, channel->local_sig_id, channel->remote_cid, channel->local_cid); 520 break; 521 default: 522 break; 523 } 524 } 525 } 526 527 uint16_t l2cap_max_mtu(void){ 528 return hci_max_acl_data_packet_length() - L2CAP_HEADER_SIZE; 529 } 530 531 // open outgoing L2CAP channel 532 void l2cap_create_channel_internal(void * connection, btstack_packet_handler_t packet_handler, 533 bd_addr_t address, uint16_t psm, uint16_t mtu){ 534 535 log_info("L2CAP_CREATE_CHANNEL_MTU addr %s psm 0x%x mtu %u", bd_addr_to_str(address), psm, mtu); 536 537 // alloc structure 538 l2cap_channel_t * chan = (l2cap_channel_t*) btstack_memory_l2cap_channel_get(); 539 if (!chan) { 540 // emit error event 541 l2cap_channel_t dummy_channel; 542 BD_ADDR_COPY(dummy_channel.address, address); 543 dummy_channel.psm = psm; 544 l2cap_emit_channel_opened(&dummy_channel, BTSTACK_MEMORY_ALLOC_FAILED); 545 return; 546 } 547 // limit local mtu to max acl packet length 548 if (mtu > l2cap_max_mtu()) { 549 mtu = l2cap_max_mtu(); 550 } 551 552 // fill in 553 BD_ADDR_COPY(chan->address, address); 554 chan->psm = psm; 555 chan->handle = 0; 556 chan->connection = connection; 557 chan->packet_handler = packet_handler; 558 chan->remote_mtu = L2CAP_MINIMAL_MTU; 559 chan->local_mtu = mtu; 560 chan->packets_granted = 0; 561 562 // set initial state 563 chan->state = L2CAP_STATE_WILL_SEND_CREATE_CONNECTION; 564 chan->state_var = L2CAP_CHANNEL_STATE_VAR_NONE; 565 chan->remote_sig_id = L2CAP_SIG_ID_INVALID; 566 chan->local_sig_id = L2CAP_SIG_ID_INVALID; 567 568 // add to connections list 569 linked_list_add(&l2cap_channels, (linked_item_t *) chan); 570 571 l2cap_run(); 572 } 573 574 void l2cap_disconnect_internal(uint16_t local_cid, uint8_t reason){ 575 log_info("L2CAP_DISCONNECT local_cid 0x%x reason 0x%x", local_cid, reason); 576 // find channel for local_cid 577 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 578 if (channel) { 579 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST; 580 } 581 // process 582 l2cap_run(); 583 } 584 585 static void l2cap_handle_connection_failed_for_addr(bd_addr_t address, uint8_t status){ 586 linked_item_t *it = (linked_item_t *) &l2cap_channels; 587 while (it->next){ 588 l2cap_channel_t * channel = (l2cap_channel_t *) it->next; 589 if ( ! BD_ADDR_CMP( channel->address, address) ){ 590 if (channel->state == L2CAP_STATE_WAIT_CONNECTION_COMPLETE || channel->state == L2CAP_STATE_WILL_SEND_CREATE_CONNECTION) { 591 // failure, forward error code 592 l2cap_emit_channel_opened(channel, status); 593 // discard channel 594 it->next = it->next->next; 595 btstack_memory_l2cap_channel_free(channel); 596 } 597 } else { 598 it = it->next; 599 } 600 } 601 } 602 603 static void l2cap_handle_connection_success_for_addr(bd_addr_t address, hci_con_handle_t handle){ 604 linked_item_t *it; 605 for (it = (linked_item_t *) l2cap_channels; it ; it = it->next){ 606 l2cap_channel_t * channel = (l2cap_channel_t *) it; 607 if ( ! BD_ADDR_CMP( channel->address, address) ){ 608 if (channel->state == L2CAP_STATE_WAIT_CONNECTION_COMPLETE || channel->state == L2CAP_STATE_WILL_SEND_CREATE_CONNECTION) { 609 // success, start l2cap handshake 610 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST; 611 channel->handle = handle; 612 channel->local_cid = l2cap_next_local_cid(); 613 } 614 } 615 } 616 // process 617 l2cap_run(); 618 } 619 620 void l2cap_event_handler( uint8_t *packet, uint16_t size ){ 621 622 bd_addr_t address; 623 hci_con_handle_t handle; 624 l2cap_channel_t * channel; 625 linked_item_t *it; 626 int hci_con_used; 627 628 switch(packet[0]){ 629 630 // handle connection complete events 631 case HCI_EVENT_CONNECTION_COMPLETE: 632 bt_flip_addr(address, &packet[5]); 633 if (packet[2] == 0){ 634 handle = READ_BT_16(packet, 3); 635 l2cap_handle_connection_success_for_addr(address, handle); 636 } else { 637 l2cap_handle_connection_failed_for_addr(address, packet[2]); 638 } 639 break; 640 641 // handle successful create connection cancel command 642 case HCI_EVENT_COMMAND_COMPLETE: 643 if ( COMMAND_COMPLETE_EVENT(packet, hci_create_connection_cancel) ) { 644 if (packet[5] == 0){ 645 bt_flip_addr(address, &packet[6]); 646 // CONNECTION TERMINATED BY LOCAL HOST (0X16) 647 l2cap_handle_connection_failed_for_addr(address, 0x16); 648 } 649 } 650 l2cap_run(); // try sending signaling packets first 651 break; 652 653 case HCI_EVENT_COMMAND_STATUS: 654 l2cap_run(); // try sending signaling packets first 655 break; 656 657 // handle disconnection complete events 658 case HCI_EVENT_DISCONNECTION_COMPLETE: 659 // send l2cap disconnect events for all channels on this handle 660 handle = READ_BT_16(packet, 3); 661 it = (linked_item_t *) &l2cap_channels; 662 while (it->next){ 663 l2cap_channel_t * channel = (l2cap_channel_t *) it->next; 664 if ( channel->handle == handle ){ 665 // update prev item before free'ing next element - don't call l2cap_finalize_channel_close 666 it->next = it->next->next; 667 l2cap_emit_channel_closed(channel); 668 btstack_memory_l2cap_channel_free(channel); 669 } else { 670 it = it->next; 671 } 672 } 673 break; 674 675 case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS: 676 l2cap_run(); // try sending signaling packets first 677 l2cap_hand_out_credits(); 678 break; 679 680 // HCI Connection Timeouts 681 case L2CAP_EVENT_TIMEOUT_CHECK: 682 handle = READ_BT_16(packet, 2); 683 if (hci_authentication_active_for_handle(handle)) break; 684 hci_con_used = 0; 685 for (it = (linked_item_t *) l2cap_channels; it ; it = it->next){ 686 channel = (l2cap_channel_t *) it; 687 if (channel->handle == handle) { 688 hci_con_used = 1; 689 } 690 } 691 if (hci_con_used) break; 692 if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) break; 693 hci_send_cmd(&hci_disconnect, handle, 0x13); // remote closed connection 694 break; 695 696 case DAEMON_EVENT_HCI_PACKET_SENT: 697 for (it = (linked_item_t *) l2cap_channels; it ; it = it->next){ 698 channel = (l2cap_channel_t *) it; 699 if (channel->packet_handler) { 700 (* (channel->packet_handler))(HCI_EVENT_PACKET, channel->local_cid, packet, size); 701 } 702 } 703 if (attribute_protocol_packet_handler) { 704 (*attribute_protocol_packet_handler)(HCI_EVENT_PACKET, 0, packet, size); 705 } 706 if (security_protocol_packet_handler) { 707 (*security_protocol_packet_handler)(HCI_EVENT_PACKET, 0, packet, size); 708 } 709 break; 710 711 default: 712 break; 713 } 714 715 // pass on 716 (*packet_handler)(NULL, HCI_EVENT_PACKET, 0, packet, size); 717 } 718 719 static void l2cap_handle_disconnect_request(l2cap_channel_t *channel, uint16_t identifier){ 720 channel->remote_sig_id = identifier; 721 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE; 722 l2cap_run(); 723 } 724 725 static void l2cap_register_signaling_response(hci_con_handle_t handle, uint8_t code, uint8_t sig_id, uint16_t data){ 726 // Vol 3, Part A, 4.3: "The DCID and SCID fields shall be ignored when the result field indi- cates the connection was refused." 727 if (signaling_responses_pending < NR_PENDING_SIGNALING_RESPONSES) { 728 signaling_responses[signaling_responses_pending].handle = handle; 729 signaling_responses[signaling_responses_pending].code = code; 730 signaling_responses[signaling_responses_pending].sig_id = sig_id; 731 signaling_responses[signaling_responses_pending].data = data; 732 signaling_responses_pending++; 733 l2cap_run(); 734 } 735 } 736 737 static void l2cap_handle_connection_request(hci_con_handle_t handle, uint8_t sig_id, uint16_t psm, uint16_t source_cid){ 738 739 // log_info("l2cap_handle_connection_request for handle %u, psm %u cid 0x%02x\n", handle, psm, source_cid); 740 l2cap_service_t *service = l2cap_get_service(psm); 741 if (!service) { 742 // 0x0002 PSM not supported 743 l2cap_register_signaling_response(handle, CONNECTION_REQUEST, sig_id, 0x0002); 744 return; 745 } 746 747 hci_connection_t * hci_connection = hci_connection_for_handle( handle ); 748 if (!hci_connection) { 749 // 750 log_error("no hci_connection for handle %u\n", handle); 751 return; 752 } 753 // alloc structure 754 // log_info("l2cap_handle_connection_request register channel\n"); 755 l2cap_channel_t * channel = (l2cap_channel_t*) btstack_memory_l2cap_channel_get(); 756 if (!channel){ 757 // 0x0004 No resources available 758 l2cap_register_signaling_response(handle, CONNECTION_REQUEST, sig_id, 0x0004); 759 return; 760 } 761 762 // fill in 763 BD_ADDR_COPY(channel->address, hci_connection->address); 764 channel->psm = psm; 765 channel->handle = handle; 766 channel->connection = service->connection; 767 channel->packet_handler = service->packet_handler; 768 channel->local_cid = l2cap_next_local_cid(); 769 channel->remote_cid = source_cid; 770 channel->local_mtu = service->mtu; 771 channel->remote_mtu = L2CAP_DEFAULT_MTU; 772 channel->packets_granted = 0; 773 channel->remote_sig_id = sig_id; 774 775 // limit local mtu to max acl packet length 776 if (channel->local_mtu > l2cap_max_mtu()) { 777 channel->local_mtu = l2cap_max_mtu(); 778 } 779 780 // set initial state 781 channel->state = L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT; 782 channel->state_var = L2CAP_CHANNEL_STATE_VAR_NONE; 783 784 // add to connections list 785 linked_list_add(&l2cap_channels, (linked_item_t *) channel); 786 787 // emit incoming connection request 788 l2cap_emit_connection_request(channel); 789 } 790 791 void l2cap_accept_connection_internal(uint16_t local_cid){ 792 log_info("L2CAP_ACCEPT_CONNECTION local_cid 0x%x", local_cid); 793 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 794 if (!channel) { 795 log_error("l2cap_accept_connection_internal called but local_cid 0x%x not found", local_cid); 796 return; 797 } 798 799 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_ACCEPT; 800 801 // process 802 l2cap_run(); 803 } 804 805 void l2cap_decline_connection_internal(uint16_t local_cid, uint8_t reason){ 806 log_info("L2CAP_DECLINE_CONNECTION local_cid 0x%x, reason %x", local_cid, reason); 807 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid( local_cid); 808 if (!channel) { 809 log_error( "l2cap_decline_connection_internal called but local_cid 0x%x not found", local_cid); 810 return; 811 } 812 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE; 813 channel->reason = reason; 814 l2cap_run(); 815 } 816 817 void l2cap_signaling_handle_configure_request(l2cap_channel_t *channel, uint8_t *command){ 818 819 channel->remote_sig_id = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 820 821 uint16_t flags = READ_BT_16(command, 6); 822 if (flags & 1) { 823 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT); 824 } 825 826 // accept the other's configuration options 827 uint16_t end_pos = 4 + READ_BT_16(command, L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET); 828 uint16_t pos = 8; 829 while (pos < end_pos){ 830 uint8_t option_hint = command[pos] >> 7; 831 uint8_t option_type = command[pos] & 0x7f; 832 log_info("l2cap cid %u, hint %u, type %u", channel->local_cid, option_hint, option_type); 833 pos++; 834 uint8_t length = command[pos++]; 835 // MTU { type(8): 1, len(8):2, MTU(16) } 836 if (option_type == 1 && length == 2){ 837 channel->remote_mtu = READ_BT_16(command, pos); 838 // log_info("l2cap cid 0x%02x, remote mtu %u\n", channel->local_cid, channel->remote_mtu); 839 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU); 840 } 841 // check for unknown options 842 if (option_hint == 0 && (option_type == 0 || option_type >= 0x07)){ 843 log_info("l2cap cid %u, unknown options", channel->local_cid); 844 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_INVALID); 845 } 846 pos += length; 847 } 848 } 849 850 static int l2cap_channel_ready_for_open(l2cap_channel_t *channel){ 851 // log_info("l2cap_channel_ready_for_open 0x%02x\n", channel->state_var); 852 if ((channel->state_var & L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_RSP) == 0) return 0; 853 if ((channel->state_var & L2CAP_CHANNEL_STATE_VAR_SENT_CONF_RSP) == 0) return 0; 854 return 1; 855 } 856 857 858 void l2cap_signaling_handler_channel(l2cap_channel_t *channel, uint8_t *command){ 859 860 uint8_t code = command[L2CAP_SIGNALING_COMMAND_CODE_OFFSET]; 861 uint8_t identifier = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 862 uint16_t result = 0; 863 864 log_info("L2CAP signaling handler code %u, state %u\n", code, channel->state); 865 866 // handle DISCONNECT REQUESTS seperately 867 if (code == DISCONNECTION_REQUEST){ 868 switch (channel->state){ 869 case L2CAP_STATE_CONFIG: 870 case L2CAP_STATE_OPEN: 871 case L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST: 872 case L2CAP_STATE_WAIT_DISCONNECT: 873 l2cap_handle_disconnect_request(channel, identifier); 874 break; 875 876 default: 877 // ignore in other states 878 break; 879 } 880 return; 881 } 882 883 // @STATEMACHINE(l2cap) 884 switch (channel->state) { 885 886 case L2CAP_STATE_WAIT_CONNECT_RSP: 887 switch (code){ 888 case CONNECTION_RESPONSE: 889 result = READ_BT_16 (command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+4); 890 switch (result) { 891 case 0: 892 // successful connection 893 channel->remote_cid = READ_BT_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 894 channel->state = L2CAP_STATE_CONFIG; 895 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 896 break; 897 case 1: 898 // connection pending. get some coffee 899 break; 900 default: 901 // channel closed 902 channel->state = L2CAP_STATE_CLOSED; 903 904 // map l2cap connection response result to BTstack status enumeration 905 l2cap_emit_channel_opened(channel, L2CAP_CONNECTION_RESPONSE_RESULT_SUCCESSFUL + result); 906 907 // drop link key if security block 908 if (L2CAP_CONNECTION_RESPONSE_RESULT_SUCCESSFUL + result == L2CAP_CONNECTION_RESPONSE_RESULT_REFUSED_SECURITY){ 909 hci_drop_link_key_for_bd_addr(&channel->address); 910 } 911 912 // discard channel 913 linked_list_remove(&l2cap_channels, (linked_item_t *) channel); 914 btstack_memory_l2cap_channel_free(channel); 915 break; 916 } 917 break; 918 919 default: 920 //@TODO: implement other signaling packets 921 break; 922 } 923 break; 924 925 case L2CAP_STATE_CONFIG: 926 result = READ_BT_16 (command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+4); 927 switch (code) { 928 case CONFIGURE_REQUEST: 929 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP); 930 l2cap_signaling_handle_configure_request(channel, command); 931 if (!(channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT)){ 932 // only done if continuation not set 933 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_REQ); 934 } 935 break; 936 case CONFIGURE_RESPONSE: 937 if (result) { 938 // retry on negative result 939 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 940 break; 941 } 942 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_RSP); 943 break; 944 default: 945 break; 946 } 947 if (l2cap_channel_ready_for_open(channel)){ 948 // for open: 949 channel->state = L2CAP_STATE_OPEN; 950 l2cap_emit_channel_opened(channel, 0); 951 l2cap_emit_credits(channel, 1); 952 } 953 break; 954 955 case L2CAP_STATE_WAIT_DISCONNECT: 956 switch (code) { 957 case DISCONNECTION_RESPONSE: 958 l2cap_finialize_channel_close(channel); 959 break; 960 default: 961 //@TODO: implement other signaling packets 962 break; 963 } 964 break; 965 966 case L2CAP_STATE_CLOSED: 967 // @TODO handle incoming requests 968 break; 969 970 case L2CAP_STATE_OPEN: 971 //@TODO: implement other signaling packets, e.g. re-configure 972 break; 973 default: 974 break; 975 } 976 // log_info("new state %u\n", channel->state); 977 } 978 979 980 void l2cap_signaling_handler_dispatch( hci_con_handle_t handle, uint8_t * command){ 981 982 // get code, signalind identifier and command len 983 uint8_t code = command[L2CAP_SIGNALING_COMMAND_CODE_OFFSET]; 984 uint8_t sig_id = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 985 986 // not for a particular channel, and not CONNECTION_REQUEST, ECHO_[REQUEST|RESPONSE], INFORMATION_REQUEST 987 if (code < 1 || code == ECHO_RESPONSE || code > INFORMATION_REQUEST){ 988 l2cap_register_signaling_response(handle, COMMAND_REJECT, sig_id, L2CAP_REJ_CMD_UNKNOWN); 989 return; 990 } 991 992 // general commands without an assigned channel 993 switch(code) { 994 995 case CONNECTION_REQUEST: { 996 uint16_t psm = READ_BT_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 997 uint16_t source_cid = READ_BT_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+2); 998 l2cap_handle_connection_request(handle, sig_id, psm, source_cid); 999 return; 1000 } 1001 1002 case ECHO_REQUEST: 1003 l2cap_register_signaling_response(handle, code, sig_id, 0); 1004 return; 1005 1006 case INFORMATION_REQUEST: { 1007 uint16_t infoType = READ_BT_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 1008 l2cap_register_signaling_response(handle, code, sig_id, infoType); 1009 return; 1010 } 1011 1012 default: 1013 break; 1014 } 1015 1016 1017 // Get potential destination CID 1018 uint16_t dest_cid = READ_BT_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 1019 1020 // Find channel for this sig_id and connection handle 1021 linked_item_t *it; 1022 for (it = (linked_item_t *) l2cap_channels; it ; it = it->next){ 1023 l2cap_channel_t * channel = (l2cap_channel_t *) it; 1024 if (channel->handle == handle) { 1025 if (code & 1) { 1026 // match odd commands (responses) by previous signaling identifier 1027 if (channel->local_sig_id == sig_id) { 1028 l2cap_signaling_handler_channel(channel, command); 1029 break; 1030 } 1031 } else { 1032 // match even commands (requests) by local channel id 1033 if (channel->local_cid == dest_cid) { 1034 l2cap_signaling_handler_channel(channel, command); 1035 break; 1036 } 1037 } 1038 } 1039 } 1040 } 1041 1042 void l2cap_acl_handler( uint8_t *packet, uint16_t size ){ 1043 1044 // Get Channel ID 1045 uint16_t channel_id = READ_L2CAP_CHANNEL_ID(packet); 1046 hci_con_handle_t handle = READ_ACL_CONNECTION_HANDLE(packet); 1047 1048 switch (channel_id) { 1049 1050 case L2CAP_CID_SIGNALING: { 1051 1052 uint16_t command_offset = 8; 1053 while (command_offset < size) { 1054 1055 // handle signaling commands 1056 l2cap_signaling_handler_dispatch(handle, &packet[command_offset]); 1057 1058 // increment command_offset 1059 command_offset += L2CAP_SIGNALING_COMMAND_DATA_OFFSET + READ_BT_16(packet, command_offset + L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET); 1060 } 1061 break; 1062 } 1063 1064 case L2CAP_CID_ATTRIBUTE_PROTOCOL: 1065 if (attribute_protocol_packet_handler) { 1066 (*attribute_protocol_packet_handler)(ATT_DATA_PACKET, handle, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1067 } 1068 break; 1069 1070 case L2CAP_CID_SECURITY_MANAGER_PROTOCOL: 1071 if (security_protocol_packet_handler) { 1072 (*security_protocol_packet_handler)(SM_DATA_PACKET, handle, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1073 } 1074 break; 1075 1076 default: { 1077 // Find channel for this channel_id and connection handle 1078 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(channel_id); 1079 if (channel) { 1080 l2cap_dispatch(channel, L2CAP_DATA_PACKET, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 1081 } 1082 break; 1083 } 1084 } 1085 1086 l2cap_run(); 1087 } 1088 1089 static void l2cap_packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){ 1090 switch (packet_type) { 1091 case HCI_EVENT_PACKET: 1092 l2cap_event_handler(packet, size); 1093 break; 1094 case HCI_ACL_DATA_PACKET: 1095 l2cap_acl_handler(packet, size); 1096 break; 1097 default: 1098 break; 1099 } 1100 } 1101 1102 // finalize closed channel - l2cap_handle_disconnect_request & DISCONNECTION_RESPONSE 1103 void l2cap_finialize_channel_close(l2cap_channel_t *channel){ 1104 channel->state = L2CAP_STATE_CLOSED; 1105 l2cap_emit_channel_closed(channel); 1106 // discard channel 1107 linked_list_remove(&l2cap_channels, (linked_item_t *) channel); 1108 btstack_memory_l2cap_channel_free(channel); 1109 } 1110 1111 l2cap_service_t * l2cap_get_service(uint16_t psm){ 1112 linked_item_t *it; 1113 1114 // close open channels 1115 for (it = (linked_item_t *) l2cap_services; it ; it = it->next){ 1116 l2cap_service_t * service = ((l2cap_service_t *) it); 1117 if ( service->psm == psm){ 1118 return service; 1119 }; 1120 } 1121 return NULL; 1122 } 1123 1124 void l2cap_register_service_internal(void *connection, btstack_packet_handler_t packet_handler, uint16_t psm, uint16_t mtu){ 1125 1126 log_info("L2CAP_REGISTER_SERVICE psm 0x%x mtu %u", psm, mtu); 1127 1128 // check for alread registered psm 1129 // TODO: emit error event 1130 l2cap_service_t *service = l2cap_get_service(psm); 1131 if (service) { 1132 log_error("l2cap_register_service_internal: PSM %u already registered\n", psm); 1133 l2cap_emit_service_registered(connection, L2CAP_SERVICE_ALREADY_REGISTERED, psm); 1134 return; 1135 } 1136 1137 // alloc structure 1138 // TODO: emit error event 1139 service = (l2cap_service_t *) btstack_memory_l2cap_service_get(); 1140 if (!service) { 1141 log_error("l2cap_register_service_internal: no memory for l2cap_service_t\n"); 1142 l2cap_emit_service_registered(connection, BTSTACK_MEMORY_ALLOC_FAILED, psm); 1143 return; 1144 } 1145 1146 // fill in 1147 service->psm = psm; 1148 service->mtu = mtu; 1149 service->connection = connection; 1150 service->packet_handler = packet_handler; 1151 1152 // add to services list 1153 linked_list_add(&l2cap_services, (linked_item_t *) service); 1154 1155 // enable page scan 1156 hci_connectable_control(1); 1157 1158 // done 1159 l2cap_emit_service_registered(connection, 0, psm); 1160 } 1161 1162 void l2cap_unregister_service_internal(void *connection, uint16_t psm){ 1163 1164 log_info("L2CAP_UNREGISTER_SERVICE psm 0x%x", psm); 1165 1166 l2cap_service_t *service = l2cap_get_service(psm); 1167 if (!service) return; 1168 linked_list_remove(&l2cap_services, (linked_item_t *) service); 1169 btstack_memory_l2cap_service_free(service); 1170 1171 // disable page scan when no services registered 1172 if (!linked_list_empty(&l2cap_services)) return; 1173 hci_connectable_control(0); 1174 } 1175 1176 // 1177 void l2cap_close_connection(void *connection){ 1178 linked_item_t *it; 1179 1180 // close open channels - note to myself: no channel is freed, so no new for fancy iterator tricks 1181 l2cap_channel_t * channel; 1182 for (it = (linked_item_t *) l2cap_channels; it ; it = it->next){ 1183 channel = (l2cap_channel_t *) it; 1184 if (channel->connection == connection) { 1185 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST; 1186 } 1187 } 1188 1189 // unregister services 1190 it = (linked_item_t *) &l2cap_services; 1191 while (it->next) { 1192 l2cap_service_t * service = (l2cap_service_t *) it->next; 1193 if (service->connection == connection){ 1194 it->next = it->next->next; 1195 btstack_memory_l2cap_service_free(service); 1196 } else { 1197 it = it->next; 1198 } 1199 } 1200 1201 // process 1202 l2cap_run(); 1203 } 1204 1205 // Bluetooth 4.0 - allows to register handler for Attribute Protocol and Security Manager Protocol 1206 void l2cap_register_fixed_channel(btstack_packet_handler_t packet_handler, uint16_t channel_id) { 1207 switch(channel_id){ 1208 case L2CAP_CID_ATTRIBUTE_PROTOCOL: 1209 attribute_protocol_packet_handler = packet_handler; 1210 break; 1211 case L2CAP_CID_SECURITY_MANAGER_PROTOCOL: 1212 security_protocol_packet_handler = packet_handler; 1213 break; 1214 } 1215 } 1216 1217