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 BLUEKITCHEN 24 * GMBH 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 #define BTSTACK_FILE__ "att_server.c" 39 40 41 // 42 // ATT Server Globals 43 // 44 45 #include <stdint.h> 46 #include <string.h> 47 #include <inttypes.h> 48 49 #include "btstack_config.h" 50 51 #include "ble/att_dispatch.h" 52 #include "ble/att_db.h" 53 #include "ble/att_server.h" 54 #include "ble/core.h" 55 #include "ble/le_device_db.h" 56 #include "ble/sm.h" 57 #include "btstack_debug.h" 58 #include "btstack_event.h" 59 #include "btstack_memory.h" 60 #include "btstack_run_loop.h" 61 #include "gap.h" 62 #include "hci.h" 63 #include "hci_dump.h" 64 #include "l2cap.h" 65 #include "btstack_tlv.h" 66 #ifdef ENABLE_LE_SIGNED_WRITE 67 #include "ble/sm.h" 68 #include "bluetooth_psm.h" 69 70 #endif 71 72 #ifdef ENABLE_TESTING_SUPPORT 73 #include <stdio.h> 74 #endif 75 76 #ifndef NVN_NUM_GATT_SERVER_CCC 77 #define NVN_NUM_GATT_SERVER_CCC 20 78 #endif 79 80 static void att_run_for_context(att_server_t * att_server, att_connection_t * att_connection); 81 static att_write_callback_t att_server_write_callback_for_handle(uint16_t handle); 82 static btstack_packet_handler_t att_server_packet_handler_for_handle(uint16_t handle); 83 static void att_server_handle_can_send_now(void); 84 static void att_server_persistent_ccc_restore(att_server_t * att_server, att_connection_t * att_connection); 85 static void att_server_persistent_ccc_clear(att_server_t * att_server); 86 static void att_server_handle_att_pdu(att_server_t * att_server, att_connection_t * att_connection, uint8_t * packet, uint16_t size); 87 88 typedef enum { 89 ATT_SERVER_RUN_PHASE_1_REQUESTS = 0, 90 ATT_SERVER_RUN_PHASE_2_INDICATIONS, 91 ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS, 92 } att_server_run_phase_t; 93 94 // 95 typedef struct { 96 uint32_t seq_nr; 97 uint16_t att_handle; 98 uint8_t value; 99 uint8_t device_index; 100 } persistent_ccc_entry_t; 101 102 // global 103 static btstack_packet_callback_registration_t hci_event_callback_registration; 104 static btstack_packet_callback_registration_t sm_event_callback_registration; 105 static btstack_packet_handler_t att_client_packet_handler; 106 static btstack_linked_list_t service_handlers; 107 static btstack_context_callback_registration_t att_client_waiting_for_can_send_registration; 108 109 static att_read_callback_t att_server_client_read_callback; 110 static att_write_callback_t att_server_client_write_callback; 111 112 // round robin 113 static hci_con_handle_t att_server_last_can_send_now = HCI_CON_HANDLE_INVALID; 114 115 #ifdef ENABLE_GATT_OVER_EATT 116 typedef struct { 117 btstack_linked_item_t item; 118 att_server_t att_server; 119 att_connection_t att_connection; 120 uint8_t * receive_buffer; 121 uint8_t * send_buffer; 122 } att_server_eatt_bearer_t; 123 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_con_handle(hci_con_handle_t con_handle); 124 static btstack_linked_list_t att_server_eatt_bearer_pool; 125 static btstack_linked_list_t att_server_eatt_bearer_active; 126 #endif 127 128 #ifdef ENABLE_LE_SIGNED_WRITE 129 static bool att_server_connections_for_state(att_server_state_t state, att_server_t ** att_server_out, att_connection_t ** att_connection_out){ 130 btstack_linked_list_iterator_t it; 131 hci_connections_get_iterator(&it); 132 while(btstack_linked_list_iterator_has_next(&it)){ 133 hci_connection_t * hci_connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 134 if (hci_connection->att_server.state == state) { 135 *att_server_out = &hci_connection->att_server; 136 *att_connection_out = &hci_connection->att_connection; 137 return true; 138 } 139 } 140 141 #ifdef ENABLE_GATT_OVER_EATT 142 btstack_linked_list_iterator_init(&it, &att_server_eatt_bearer_active); 143 while(btstack_linked_list_iterator_has_next(&it)){ 144 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) btstack_linked_list_iterator_next(&it); 145 if (eatt_bearer->att_server.state == state) { 146 *att_server_out = &eatt_bearer->att_server; 147 *att_connection_out = &eatt_bearer->att_connection; 148 return true; 149 } 150 } 151 #endif 152 153 return false; 154 } 155 #endif 156 157 static void att_server_request_can_send_now(att_server_t * att_server, att_connection_t * att_connection ){ 158 switch (att_server->bearer_type){ 159 case ATT_BEARER_UNENHANCED_LE: 160 #ifdef ENABLE_GATT_OVER_CLASSIC 161 case ATT_BEARER_UNENHANCED_CLASSIC: 162 /* fall through */ 163 #endif 164 att_dispatch_server_request_can_send_now_event(att_connection->con_handle); 165 break; 166 #ifdef ENABLE_GATT_OVER_EATT 167 case ATT_BEARER_ENHANCED_LE: 168 l2cap_request_can_send_now_event(att_server->l2cap_cid); 169 break; 170 #endif 171 default: 172 btstack_unreachable(); 173 break; 174 } 175 } 176 177 static bool att_server_can_send_packet(att_server_t * att_server, att_connection_t * att_connection){ 178 switch (att_server->bearer_type) { 179 case ATT_BEARER_UNENHANCED_LE: 180 #ifdef ENABLE_GATT_OVER_CLASSIC 181 case ATT_BEARER_UNENHANCED_CLASSIC: 182 /* fall through */ 183 #endif 184 return att_dispatch_server_can_send_now(att_connection->con_handle); 185 #ifdef ENABLE_GATT_OVER_EATT 186 case ATT_BEARER_ENHANCED_LE: 187 return l2cap_can_send_packet_now(att_server->l2cap_cid); 188 #endif 189 default: 190 btstack_unreachable(); 191 break; 192 } 193 return false; 194 } 195 196 static void att_handle_value_indication_notify_client(uint8_t status, uint16_t client_handle, uint16_t attribute_handle){ 197 btstack_packet_handler_t packet_handler = att_server_packet_handler_for_handle(attribute_handle); 198 if (!packet_handler) return; 199 200 uint8_t event[7]; 201 int pos = 0; 202 event[pos++] = ATT_EVENT_HANDLE_VALUE_INDICATION_COMPLETE; 203 event[pos++] = sizeof(event) - 2u; 204 event[pos++] = status; 205 little_endian_store_16(event, pos, client_handle); 206 pos += 2; 207 little_endian_store_16(event, pos, attribute_handle); 208 (*packet_handler)(HCI_EVENT_PACKET, 0, &event[0], sizeof(event)); 209 } 210 211 static void att_emit_event_to_all(const uint8_t * event, uint16_t size){ 212 // dispatch to app level handler 213 if (att_client_packet_handler != NULL){ 214 (*att_client_packet_handler)(HCI_EVENT_PACKET, 0, (uint8_t*) event, size); 215 } 216 217 // dispatch to service handlers 218 btstack_linked_list_iterator_t it; 219 btstack_linked_list_iterator_init(&it, &service_handlers); 220 while (btstack_linked_list_iterator_has_next(&it)){ 221 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 222 if (!handler->packet_handler) continue; 223 (*handler->packet_handler)(HCI_EVENT_PACKET, 0, (uint8_t*) event, size); 224 } 225 } 226 227 static void att_emit_mtu_event(hci_con_handle_t con_handle, uint16_t mtu){ 228 uint8_t event[6]; 229 int pos = 0; 230 event[pos++] = ATT_EVENT_MTU_EXCHANGE_COMPLETE; 231 event[pos++] = sizeof(event) - 2u; 232 little_endian_store_16(event, pos, con_handle); 233 pos += 2; 234 little_endian_store_16(event, pos, mtu); 235 236 // also dispatch to GATT Clients 237 att_dispatch_server_mtu_exchanged(con_handle, mtu); 238 239 // dispatch to app level handler and service handlers 240 att_emit_event_to_all(&event[0], sizeof(event)); 241 } 242 243 static void att_emit_can_send_now_event(void * context){ 244 UNUSED(context); 245 if (!att_client_packet_handler) return; 246 247 uint8_t event[] = { ATT_EVENT_CAN_SEND_NOW, 0}; 248 (*att_client_packet_handler)(HCI_EVENT_PACKET, 0, &event[0], sizeof(event)); 249 } 250 251 static void att_emit_connected_event(att_server_t * att_server, att_connection_t * att_connection){ 252 uint8_t event[11]; 253 int pos = 0; 254 event[pos++] = ATT_EVENT_CONNECTED; 255 event[pos++] = sizeof(event) - 2u; 256 event[pos++] = att_server->peer_addr_type; 257 reverse_bd_addr(att_server->peer_address, &event[pos]); 258 pos += 6; 259 little_endian_store_16(event, pos, att_connection->con_handle); 260 pos += 2; 261 262 // dispatch to app level handler and service handlers 263 att_emit_event_to_all(&event[0], sizeof(event)); 264 } 265 266 267 static void att_emit_disconnected_event(uint16_t con_handle){ 268 uint8_t event[4]; 269 int pos = 0; 270 event[pos++] = ATT_EVENT_DISCONNECTED; 271 event[pos++] = sizeof(event) - 2u; 272 little_endian_store_16(event, pos, con_handle); 273 pos += 2; 274 275 // dispatch to app level handler and service handlers 276 att_emit_event_to_all(&event[0], sizeof(event)); 277 } 278 279 static void att_handle_value_indication_timeout(btstack_timer_source_t *ts){ 280 void * context = btstack_run_loop_get_timer_context(ts); 281 hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) context; 282 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 283 if (!hci_connection) return; 284 // @note: after a transaction timeout, no more requests shall be sent over this ATT Bearer 285 // (that's why we don't reset the value_indication_handle) 286 att_server_t * att_server = &hci_connection->att_server; 287 uint16_t att_handle = att_server->value_indication_handle; 288 att_connection_t * att_connection = &hci_connection->att_connection; 289 att_handle_value_indication_notify_client((uint8_t)ATT_HANDLE_VALUE_INDICATION_TIMEOUT, att_connection->con_handle, att_handle); 290 } 291 292 static void att_event_packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 293 294 UNUSED(channel); // ok: there is no channel 295 UNUSED(size); // ok: handling own l2cap events 296 297 att_server_t * att_server; 298 att_connection_t * att_connection; 299 hci_con_handle_t con_handle; 300 hci_connection_t * hci_connection; 301 #ifdef ENABLE_GATT_OVER_CLASSIC 302 bd_addr_t address; 303 btstack_linked_list_iterator_t it; 304 #endif 305 306 switch (packet_type) { 307 308 case HCI_EVENT_PACKET: 309 switch (hci_event_packet_get_type(packet)) { 310 311 #ifdef ENABLE_GATT_OVER_CLASSIC 312 case L2CAP_EVENT_CHANNEL_OPENED: 313 con_handle = l2cap_event_channel_opened_get_handle(packet); 314 hci_connection = hci_connection_for_handle(con_handle); 315 if (!hci_connection) break; 316 att_server = &hci_connection->att_server; 317 // store connection info 318 att_server->bearer_type = ATT_BEARER_UNENHANCED_CLASSIC; 319 att_server->peer_addr_type = BD_ADDR_TYPE_ACL; 320 l2cap_event_channel_opened_get_address(packet, att_server->peer_address); 321 att_connection = &hci_connection->att_connection; 322 att_connection->con_handle = con_handle; 323 att_server->l2cap_cid = l2cap_event_channel_opened_get_local_cid(packet); 324 // reset connection properties 325 att_server->state = ATT_SERVER_IDLE; 326 att_connection->mtu = l2cap_event_channel_opened_get_remote_mtu(packet); 327 att_connection->max_mtu = l2cap_max_mtu(); 328 if (att_connection->max_mtu > ATT_REQUEST_BUFFER_SIZE){ 329 att_connection->max_mtu = ATT_REQUEST_BUFFER_SIZE; 330 } 331 332 log_info("Connection opened %s, l2cap cid %04x, mtu %u", bd_addr_to_str(address), att_server->l2cap_cid, att_connection->mtu); 333 334 // update security params 335 att_connection->encryption_key_size = gap_encryption_key_size(con_handle); 336 att_connection->authenticated = gap_authenticated(con_handle); 337 att_connection->secure_connection = gap_secure_connection(con_handle); 338 log_info("encrypted key size %u, authenticated %u, secure connection %u", 339 att_connection->encryption_key_size, att_connection->authenticated, att_connection->secure_connection); 340 341 // notify connection opened 342 att_emit_connected_event(att_server, att_connection); 343 344 // restore persisten ccc if encrypted 345 if ( gap_security_level(con_handle) >= LEVEL_2){ 346 att_server_persistent_ccc_restore(att_server, att_connection); 347 } 348 // TODO: what to do about le device db? 349 att_server->pairing_active = 0; 350 break; 351 case L2CAP_EVENT_CAN_SEND_NOW: 352 att_server_handle_can_send_now(); 353 break; 354 355 #endif 356 case HCI_EVENT_LE_META: 357 switch (packet[2]) { 358 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE: 359 con_handle = little_endian_read_16(packet, 4); 360 hci_connection = hci_connection_for_handle(con_handle); 361 if (!hci_connection) break; 362 att_server = &hci_connection->att_server; 363 // store connection info 364 att_server->peer_addr_type = packet[7]; 365 reverse_bd_addr(&packet[8], att_server->peer_address); 366 att_connection = &hci_connection->att_connection; 367 att_connection->con_handle = con_handle; 368 // reset connection properties 369 att_server->state = ATT_SERVER_IDLE; 370 att_server->bearer_type = ATT_BEARER_UNENHANCED_LE; 371 att_connection->mtu = ATT_DEFAULT_MTU; 372 att_connection->max_mtu = l2cap_max_le_mtu(); 373 if (att_connection->max_mtu > ATT_REQUEST_BUFFER_SIZE){ 374 att_connection->max_mtu = ATT_REQUEST_BUFFER_SIZE; 375 } 376 att_connection->encryption_key_size = 0u; 377 att_connection->authenticated = 0u; 378 att_connection->authorized = 0u; 379 // workaround: identity resolving can already be complete, at least store result 380 att_server->ir_le_device_db_index = sm_le_device_index(con_handle); 381 att_server->ir_lookup_active = 0u; 382 att_server->pairing_active = 0u; 383 // notify all - old 384 att_emit_event_to_all(packet, size); 385 // notify all - new 386 att_emit_connected_event(att_server, att_connection); 387 break; 388 389 default: 390 break; 391 } 392 break; 393 394 case HCI_EVENT_ENCRYPTION_CHANGE: 395 case HCI_EVENT_ENCRYPTION_CHANGE_V2: 396 case HCI_EVENT_ENCRYPTION_KEY_REFRESH_COMPLETE: 397 // check handle 398 con_handle = little_endian_read_16(packet, 3); 399 hci_connection = hci_connection_for_handle(con_handle); 400 if (!hci_connection) break; 401 if (gap_get_connection_type(con_handle) != GAP_CONNECTION_LE) break; 402 // update security params 403 att_server = &hci_connection->att_server; 404 att_connection = &hci_connection->att_connection; 405 att_connection->encryption_key_size = gap_encryption_key_size(con_handle); 406 att_connection->authenticated = gap_authenticated(con_handle) ? 1 : 0; 407 att_connection->secure_connection = gap_secure_connection(con_handle) ? 1 : 0; 408 log_info("encrypted key size %u, authenticated %u, secure connection %u", 409 att_connection->encryption_key_size, att_connection->authenticated, att_connection->secure_connection); 410 if (hci_event_packet_get_type(packet) == HCI_EVENT_ENCRYPTION_CHANGE){ 411 // restore CCC values when encrypted for LE Connections 412 if (hci_event_encryption_change_get_encryption_enabled(packet) != 0){ 413 att_server_persistent_ccc_restore(att_server, att_connection); 414 } 415 } 416 att_run_for_context(att_server, att_connection); 417 break; 418 419 case HCI_EVENT_DISCONNECTION_COMPLETE: 420 // check handle 421 con_handle = hci_event_disconnection_complete_get_connection_handle(packet); 422 hci_connection = hci_connection_for_handle(con_handle); 423 if (!hci_connection) break; 424 att_server = &hci_connection->att_server; 425 att_connection = &hci_connection->att_connection; 426 att_clear_transaction_queue(att_connection); 427 att_connection->con_handle = 0; 428 att_server->pairing_active = 0; 429 att_server->state = ATT_SERVER_IDLE; 430 if (att_server->value_indication_handle != 0u){ 431 btstack_run_loop_remove_timer(&att_server->value_indication_timer); 432 uint16_t att_handle = att_server->value_indication_handle; 433 att_server->value_indication_handle = 0u; // reset error state 434 att_handle_value_indication_notify_client((uint8_t)ATT_HANDLE_VALUE_INDICATION_DISCONNECT, att_connection->con_handle, att_handle); 435 } 436 // notify all - new 437 att_emit_disconnected_event(con_handle); 438 // notify all - old 439 att_emit_event_to_all(packet, size); 440 break; 441 442 // Identity Resolving 443 case SM_EVENT_IDENTITY_RESOLVING_STARTED: 444 con_handle = sm_event_identity_resolving_started_get_handle(packet); 445 hci_connection = hci_connection_for_handle(con_handle); 446 if (!hci_connection) break; 447 att_server = &hci_connection->att_server; 448 log_info("SM_EVENT_IDENTITY_RESOLVING_STARTED"); 449 att_server->ir_lookup_active = 1; 450 break; 451 case SM_EVENT_IDENTITY_RESOLVING_SUCCEEDED: 452 con_handle = sm_event_identity_created_get_handle(packet); 453 hci_connection = hci_connection_for_handle(con_handle); 454 if (!hci_connection) return; 455 att_connection = &hci_connection->att_connection; 456 att_server = &hci_connection->att_server; 457 att_server->ir_lookup_active = 0; 458 att_server->ir_le_device_db_index = sm_event_identity_resolving_succeeded_get_index(packet); 459 log_info("SM_EVENT_IDENTITY_RESOLVING_SUCCEEDED"); 460 att_run_for_context(att_server, att_connection); 461 break; 462 case SM_EVENT_IDENTITY_RESOLVING_FAILED: 463 con_handle = sm_event_identity_resolving_failed_get_handle(packet); 464 hci_connection = hci_connection_for_handle(con_handle); 465 if (!hci_connection) break; 466 att_connection = &hci_connection->att_connection; 467 att_server = &hci_connection->att_server; 468 log_info("SM_EVENT_IDENTITY_RESOLVING_FAILED"); 469 att_server->ir_lookup_active = 0; 470 att_server->ir_le_device_db_index = -1; 471 att_run_for_context(att_server, att_connection); 472 break; 473 474 // Pairing started - delete stored CCC values 475 // - assumes pairing indicates either new device or re-pairing, in both cases there should be no stored CCC values 476 // - assumes that all events have the con handle as the first field 477 case SM_EVENT_JUST_WORKS_REQUEST: 478 case SM_EVENT_PASSKEY_DISPLAY_NUMBER: 479 case SM_EVENT_PASSKEY_INPUT_NUMBER: 480 case SM_EVENT_NUMERIC_COMPARISON_REQUEST: 481 con_handle = sm_event_just_works_request_get_handle(packet); 482 hci_connection = hci_connection_for_handle(con_handle); 483 if (!hci_connection) break; 484 att_server = &hci_connection->att_server; 485 log_info("SM Pairing started"); 486 att_server->pairing_active = 1; 487 if (att_server->ir_le_device_db_index < 0) break; 488 att_server_persistent_ccc_clear(att_server); 489 // index not valid anymore 490 att_server->ir_le_device_db_index = -1; 491 break; 492 493 // Bonding completed 494 case SM_EVENT_IDENTITY_CREATED: 495 con_handle = sm_event_identity_created_get_handle(packet); 496 hci_connection = hci_connection_for_handle(con_handle); 497 if (!hci_connection) return; 498 att_connection = &hci_connection->att_connection; 499 att_server = &hci_connection->att_server; 500 att_server->pairing_active = 0; 501 att_server->ir_le_device_db_index = sm_event_identity_created_get_index(packet); 502 att_run_for_context(att_server, att_connection); 503 break; 504 505 // Pairing complete (with/without bonding=storing of pairing information) 506 case SM_EVENT_PAIRING_COMPLETE: 507 con_handle = sm_event_pairing_complete_get_handle(packet); 508 hci_connection = hci_connection_for_handle(con_handle); 509 if (!hci_connection) return; 510 att_connection = &hci_connection->att_connection; 511 att_server = &hci_connection->att_server; 512 att_server->pairing_active = 0; 513 att_run_for_context(att_server, att_connection); 514 break; 515 516 // Authorization 517 case SM_EVENT_AUTHORIZATION_RESULT: { 518 con_handle = sm_event_authorization_result_get_handle(packet); 519 hci_connection = hci_connection_for_handle(con_handle); 520 if (!hci_connection) break; 521 att_connection = &hci_connection->att_connection; 522 att_server = &hci_connection->att_server; 523 att_connection->authorized = sm_event_authorization_result_get_authorization_result(packet); 524 att_server_request_can_send_now(att_server, att_connection); 525 break; 526 } 527 default: 528 break; 529 } 530 break; 531 #ifdef ENABLE_GATT_OVER_CLASSIC 532 case L2CAP_DATA_PACKET: 533 hci_connections_get_iterator(&it); 534 while(btstack_linked_list_iterator_has_next(&it)){ 535 hci_connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 536 att_server = &hci_connection->att_server; 537 att_connection = &hci_connection->att_connection; 538 if (att_server->l2cap_cid == channel) { 539 att_server_handle_att_pdu(att_server, att_connection, packet, size); 540 break; 541 } 542 } 543 break; 544 #endif 545 546 default: 547 break; 548 } 549 } 550 551 static uint8_t 552 att_server_send_prepared(const att_server_t *att_server, const att_connection_t *att_connection, uint8_t *buffer, 553 uint16_t size) { 554 uint8_t status = ERROR_CODE_SUCCESS; 555 switch (att_server->bearer_type) { 556 case ATT_BEARER_UNENHANCED_LE: 557 status = l2cap_send_prepared_connectionless(att_connection->con_handle, L2CAP_CID_ATTRIBUTE_PROTOCOL, size); 558 break; 559 #ifdef ENABLE_GATT_OVER_CLASSIC 560 case ATT_BEARER_UNENHANCED_CLASSIC: 561 status = l2cap_send_prepared(att_server->l2cap_cid, size); 562 break; 563 #endif 564 #ifdef ENABLE_GATT_OVER_EATT 565 case ATT_BEARER_ENHANCED_LE: 566 btstack_assert(buffer != NULL); 567 status = l2cap_send(att_server->l2cap_cid, buffer, size); 568 break; 569 #endif 570 default: 571 btstack_unreachable(); 572 break; 573 } 574 return status; 575 } 576 577 #ifdef ENABLE_LE_SIGNED_WRITE 578 static void att_signed_write_handle_cmac_result(uint8_t hash[8]){ 579 att_server_t * att_server = NULL; 580 att_connection_t * att_connection = NULL; 581 bool found = att_server_connections_for_state(ATT_SERVER_W4_SIGNED_WRITE_VALIDATION, &att_server, &att_connection); 582 583 if (found == false){ 584 return; 585 } 586 587 uint8_t hash_flipped[8]; 588 reverse_64(hash, hash_flipped); 589 if (memcmp(hash_flipped, &att_server->request_buffer[att_server->request_size-8], 8) != 0){ 590 log_info("ATT Signed Write, invalid signature"); 591 #ifdef ENABLE_TESTING_SUPPORT 592 printf("ATT Signed Write, invalid signature\n"); 593 #endif 594 att_server->state = ATT_SERVER_IDLE; 595 return; 596 } 597 log_info("ATT Signed Write, valid signature"); 598 #ifdef ENABLE_TESTING_SUPPORT 599 printf("ATT Signed Write, valid signature\n"); 600 #endif 601 602 // update sequence number 603 uint32_t counter_packet = little_endian_read_32(att_server->request_buffer, att_server->request_size-12); 604 le_device_db_remote_counter_set(att_server->ir_le_device_db_index, counter_packet+1); 605 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 606 att_server_request_can_send_now(att_server, att_connection); 607 } 608 #endif 609 610 // pre: att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED 611 // pre: can send now 612 // uses l2cap outgoing buffer if no eatt_buffer provided 613 // returns: 1 if packet was sent 614 static int 615 att_server_process_validated_request(att_server_t *att_server, att_connection_t *att_connection, uint8_t *eatt_buffer) { 616 617 uint8_t * att_response_buffer; 618 if (eatt_buffer != NULL){ 619 att_response_buffer = eatt_buffer; 620 } else { 621 l2cap_reserve_packet_buffer(); 622 att_response_buffer = l2cap_get_outgoing_buffer(); 623 } 624 625 uint16_t att_response_size = 0; 626 // Send Error Response for MTU Request over connection-oriented channel 627 if ((att_server->bearer_type != ATT_BEARER_UNENHANCED_LE) && (att_server->request_buffer[0] == ATT_EXCHANGE_MTU_REQUEST)){ 628 att_response_size = 5; 629 att_response_buffer[0] = ATT_ERROR_RESPONSE; 630 att_response_buffer[1] = ATT_EXCHANGE_MTU_REQUEST; 631 att_response_buffer[2] = 0; 632 att_response_buffer[3] = 0; 633 att_response_buffer[4] = ATT_ERROR_REQUEST_NOT_SUPPORTED; 634 } else { 635 att_response_size = att_handle_request(att_connection, att_server->request_buffer, att_server->request_size, att_response_buffer); 636 } 637 638 #ifdef ENABLE_ATT_DELAYED_RESPONSE 639 if ((att_response_size == ATT_READ_RESPONSE_PENDING) || (att_response_size == ATT_INTERNAL_WRITE_RESPONSE_PENDING)){ 640 // update state 641 att_server->state = ATT_SERVER_RESPONSE_PENDING; 642 643 // callback with handle ATT_READ_RESPONSE_PENDING for reads 644 if (att_response_size == ATT_READ_RESPONSE_PENDING){ 645 att_server_client_read_callback(att_connection->con_handle, ATT_READ_RESPONSE_PENDING, 0, NULL, 0); 646 } 647 648 // free reserved buffer 649 if (eatt_buffer == NULL){ 650 l2cap_release_packet_buffer(); 651 } 652 return 0; 653 } 654 #endif 655 656 // intercept "insufficient authorization" for authenticated connections to allow for user authorization 657 if ((att_response_size >= 4u) 658 && (att_response_buffer[0] == ATT_ERROR_RESPONSE) 659 && (att_response_buffer[4] == ATT_ERROR_INSUFFICIENT_AUTHORIZATION) 660 && (att_connection->authenticated != 0u)){ 661 662 switch (gap_authorization_state(att_connection->con_handle)){ 663 case AUTHORIZATION_UNKNOWN: 664 if (eatt_buffer == NULL){ 665 l2cap_release_packet_buffer(); 666 } 667 sm_request_pairing(att_connection->con_handle); 668 return 0; 669 case AUTHORIZATION_PENDING: 670 if (eatt_buffer == NULL){ 671 l2cap_release_packet_buffer(); 672 } 673 return 0; 674 default: 675 break; 676 } 677 } 678 679 att_server->state = ATT_SERVER_IDLE; 680 if (att_response_size == 0u) { 681 if (eatt_buffer == NULL){ 682 l2cap_release_packet_buffer(); 683 } 684 return 0; 685 } 686 687 (void) att_server_send_prepared(att_server, att_connection, eatt_buffer, att_response_size); 688 689 // notify client about MTU exchange result 690 if (att_response_buffer[0] == ATT_EXCHANGE_MTU_RESPONSE){ 691 att_emit_mtu_event(att_connection->con_handle, att_connection->mtu); 692 } 693 return 1; 694 } 695 696 #ifdef ENABLE_ATT_DELAYED_RESPONSE 697 uint8_t att_server_response_ready(hci_con_handle_t con_handle){ 698 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 699 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 700 att_server_t * att_server = &hci_connection->att_server; 701 att_connection_t * att_connection = &hci_connection->att_connection; 702 if (att_server->state != ATT_SERVER_RESPONSE_PENDING) return ERROR_CODE_COMMAND_DISALLOWED; 703 704 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 705 att_server_request_can_send_now(att_server, att_connection); 706 return ERROR_CODE_SUCCESS; 707 } 708 #endif 709 710 static void att_run_for_context(att_server_t * att_server, att_connection_t * att_connection){ 711 switch (att_server->state){ 712 case ATT_SERVER_REQUEST_RECEIVED: 713 switch (att_server->bearer_type){ 714 case ATT_BEARER_UNENHANCED_LE: 715 // wait until re-encryption as central is complete 716 if (gap_reconnect_security_setup_active(att_connection->con_handle)) { 717 return; 718 }; 719 break; 720 #if defined(ENABLE_GATT_OVER_CLASSIC) || defined (ENABLE_GATT_OVER_EATT) 721 #ifdef ENABLE_GATT_OVER_CLASSIC 722 case ATT_BEARER_UNENHANCED_CLASSIC: 723 /* fall through */ 724 #endif 725 #ifdef ENABLE_GATT_OVER_EATT 726 case ATT_BEARER_ENHANCED_LE: 727 #endif 728 // ok 729 break; 730 #endif 731 default: 732 btstack_unreachable(); 733 break; 734 } 735 736 // wait until pairing is complete 737 if (att_server->pairing_active) break; 738 739 #ifdef ENABLE_LE_SIGNED_WRITE 740 if (att_server->request_buffer[0] == ATT_SIGNED_WRITE_COMMAND){ 741 log_info("ATT Signed Write!"); 742 if (!sm_cmac_ready()) { 743 log_info("ATT Signed Write, sm_cmac engine not ready. Abort"); 744 att_server->state = ATT_SERVER_IDLE; 745 return; 746 } 747 if (att_server->request_size < (3 + 12)) { 748 log_info("ATT Signed Write, request to short. Abort."); 749 att_server->state = ATT_SERVER_IDLE; 750 return; 751 } 752 if (att_server->ir_lookup_active){ 753 return; 754 } 755 if (att_server->ir_le_device_db_index < 0){ 756 log_info("ATT Signed Write, CSRK not available"); 757 att_server->state = ATT_SERVER_IDLE; 758 return; 759 } 760 761 // check counter 762 uint32_t counter_packet = little_endian_read_32(att_server->request_buffer, att_server->request_size-12); 763 uint32_t counter_db = le_device_db_remote_counter_get(att_server->ir_le_device_db_index); 764 log_info("ATT Signed Write, DB counter %"PRIu32", packet counter %"PRIu32, counter_db, counter_packet); 765 if (counter_packet < counter_db){ 766 log_info("ATT Signed Write, db reports higher counter, abort"); 767 att_server->state = ATT_SERVER_IDLE; 768 return; 769 } 770 771 // signature is { sequence counter, secure hash } 772 sm_key_t csrk; 773 le_device_db_remote_csrk_get(att_server->ir_le_device_db_index, csrk); 774 att_server->state = ATT_SERVER_W4_SIGNED_WRITE_VALIDATION; 775 log_info("Orig Signature: "); 776 log_info_hexdump( &att_server->request_buffer[att_server->request_size-8], 8); 777 uint16_t attribute_handle = little_endian_read_16(att_server->request_buffer, 1); 778 sm_cmac_signed_write_start(csrk, att_server->request_buffer[0], attribute_handle, att_server->request_size - 15, &att_server->request_buffer[3], counter_packet, att_signed_write_handle_cmac_result); 779 return; 780 } 781 #endif 782 // move on 783 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 784 att_server_request_can_send_now(att_server, att_connection); 785 break; 786 787 default: 788 break; 789 } 790 } 791 792 static bool att_server_data_ready_for_phase(att_server_t * att_server, att_server_run_phase_t phase){ 793 switch (phase){ 794 case ATT_SERVER_RUN_PHASE_1_REQUESTS: 795 return att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 796 case ATT_SERVER_RUN_PHASE_2_INDICATIONS: 797 return (!btstack_linked_list_empty(&att_server->indication_requests) && (att_server->value_indication_handle == 0u)); 798 case ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS: 799 return (!btstack_linked_list_empty(&att_server->notification_requests)); 800 default: 801 btstack_assert(false); 802 return false; 803 } 804 } 805 806 static void att_server_trigger_send_for_phase(att_server_t * att_server, att_connection_t * att_connection, att_server_run_phase_t phase){ 807 btstack_context_callback_registration_t * client; 808 switch (phase){ 809 case ATT_SERVER_RUN_PHASE_1_REQUESTS: 810 att_server_process_validated_request(att_server, att_connection, NULL); 811 break; 812 case ATT_SERVER_RUN_PHASE_2_INDICATIONS: 813 client = (btstack_context_callback_registration_t*) att_server->indication_requests; 814 btstack_linked_list_remove(&att_server->indication_requests, (btstack_linked_item_t *) client); 815 client->callback(client->context); 816 break; 817 case ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS: 818 client = (btstack_context_callback_registration_t*) att_server->notification_requests; 819 btstack_linked_list_remove(&att_server->notification_requests, (btstack_linked_item_t *) client); 820 client->callback(client->context); 821 break; 822 default: 823 btstack_assert(false); 824 break; 825 } 826 } 827 828 static void att_server_handle_can_send_now(void){ 829 830 hci_con_handle_t last_send_con_handle = HCI_CON_HANDLE_INVALID; 831 hci_connection_t * request_hci_connection = NULL; 832 bool can_send_now = true; 833 uint8_t phase_index; 834 835 for (phase_index = ATT_SERVER_RUN_PHASE_1_REQUESTS; phase_index <= ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS; phase_index++){ 836 att_server_run_phase_t phase = (att_server_run_phase_t) phase_index; 837 hci_con_handle_t skip_connections_until = att_server_last_can_send_now; 838 while (true){ 839 btstack_linked_list_iterator_t it; 840 hci_connections_get_iterator(&it); 841 while(btstack_linked_list_iterator_has_next(&it)){ 842 hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 843 att_server_t * att_server = &connection->att_server; 844 att_connection_t * att_connection = &connection->att_connection; 845 846 bool data_ready = att_server_data_ready_for_phase(att_server, phase); 847 848 // log_debug("phase %u, handle 0x%04x, skip until 0x%04x, data ready %u", phase, att_connection->con_handle, skip_connections_until, data_ready); 849 850 // skip until last sender found (which is also skipped) 851 if (skip_connections_until != HCI_CON_HANDLE_INVALID){ 852 if (data_ready && (request_hci_connection == NULL)){ 853 request_hci_connection = connection; 854 } 855 if (skip_connections_until == att_connection->con_handle){ 856 skip_connections_until = HCI_CON_HANDLE_INVALID; 857 } 858 continue; 859 }; 860 861 if (data_ready){ 862 if (can_send_now){ 863 att_server_trigger_send_for_phase(att_server, att_connection, phase); 864 last_send_con_handle = att_connection->con_handle; 865 can_send_now = att_server_can_send_packet(att_server, att_connection); 866 data_ready = att_server_data_ready_for_phase(att_server, phase); 867 if (data_ready && (request_hci_connection == NULL)){ 868 request_hci_connection = connection; 869 } 870 } else { 871 request_hci_connection = connection; 872 break; 873 } 874 } 875 } 876 877 // stop skipping (handles disconnect by last send connection) 878 skip_connections_until = HCI_CON_HANDLE_INVALID; 879 880 // Exit loop, if we cannot send 881 if (!can_send_now) break; 882 883 // Exit loop, if we can send but there are also no further request 884 if (request_hci_connection == NULL) break; 885 886 // Finally, if we still can send and there are requests, just try again 887 request_hci_connection = NULL; 888 } 889 // update last send con handle for round robin 890 if (last_send_con_handle != HCI_CON_HANDLE_INVALID){ 891 att_server_last_can_send_now = last_send_con_handle; 892 } 893 } 894 895 if (request_hci_connection == NULL) return; 896 897 att_server_t * att_server = &request_hci_connection->att_server; 898 att_connection_t * att_connection = &request_hci_connection->att_connection; 899 att_server_request_can_send_now(att_server, att_connection); 900 } 901 902 static void att_server_handle_att_pdu(att_server_t * att_server, att_connection_t * att_connection, uint8_t * packet, uint16_t size){ 903 904 uint8_t opcode = packet[0u]; 905 uint8_t method = opcode & 0x03fu; 906 bool invalid = method > ATT_MULTIPLE_HANDLE_VALUE_NTF; 907 bool command = (opcode & 0x40u) != 0u; 908 909 // ignore invalid commands 910 if (invalid && command){ 911 return; 912 } 913 914 // handle value indication confirms 915 if ((opcode == ATT_HANDLE_VALUE_CONFIRMATION) && (att_server->value_indication_handle != 0u)){ 916 btstack_run_loop_remove_timer(&att_server->value_indication_timer); 917 uint16_t att_handle = att_server->value_indication_handle; 918 att_server->value_indication_handle = 0u; 919 att_handle_value_indication_notify_client(0u, att_connection->con_handle, att_handle); 920 att_server_request_can_send_now(att_server, att_connection); 921 return; 922 } 923 924 // directly process command 925 // note: signed write cannot be handled directly as authentication needs to be verified 926 if (opcode == ATT_WRITE_COMMAND){ 927 att_handle_request(att_connection, packet, size, NULL); 928 return; 929 } 930 931 // check size 932 if (size > sizeof(att_server->request_buffer)) { 933 log_info("drop att pdu 0x%02x as size %u > att_server->request_buffer %u", packet[0], size, (int) sizeof(att_server->request_buffer)); 934 return; 935 } 936 937 #ifdef ENABLE_LE_SIGNED_WRITE 938 // abort signed write validation if a new request comes in (but finish previous signed write if possible) 939 if (att_server->state == ATT_SERVER_W4_SIGNED_WRITE_VALIDATION){ 940 if (packet[0] == ATT_SIGNED_WRITE_COMMAND){ 941 log_info("skip new signed write request as previous is in validation"); 942 return; 943 } else { 944 log_info("abort signed write validation to process new request"); 945 att_server->state = ATT_SERVER_IDLE; 946 } 947 } 948 #endif 949 // last request still in processing? 950 if (att_server->state != ATT_SERVER_IDLE){ 951 log_info("skip att pdu 0x%02x as server not idle (state %u)", packet[0], att_server->state); 952 return; 953 } 954 955 // store request 956 att_server->state = ATT_SERVER_REQUEST_RECEIVED; 957 att_server->request_size = size; 958 (void)memcpy(att_server->request_buffer, packet, size); 959 960 att_run_for_context(att_server, att_connection); 961 } 962 963 static void att_packet_handler(uint8_t packet_type, uint16_t handle, uint8_t *packet, uint16_t size){ 964 hci_connection_t * hci_connection; 965 att_connection_t * att_connection; 966 att_server_t * att_server; 967 968 switch (packet_type){ 969 case HCI_EVENT_PACKET: 970 switch (packet[0]){ 971 case L2CAP_EVENT_CAN_SEND_NOW: 972 att_server_handle_can_send_now(); 973 break; 974 case ATT_EVENT_MTU_EXCHANGE_COMPLETE: 975 // GATT client has negotiated the mtu for this connection 976 hci_connection = hci_connection_for_handle(handle); 977 if (!hci_connection) break; 978 att_connection = &hci_connection->att_connection; 979 att_connection->mtu = little_endian_read_16(packet, 4); 980 break; 981 default: 982 break; 983 } 984 break; 985 986 case ATT_DATA_PACKET: 987 log_debug("ATT Packet, handle 0x%04x", handle); 988 hci_connection = hci_connection_for_handle(handle); 989 if (!hci_connection) break; 990 991 att_server = &hci_connection->att_server; 992 att_connection = &hci_connection->att_connection; 993 att_server_handle_att_pdu(att_server, att_connection, packet, size); 994 break; 995 996 default: 997 break; 998 } 999 } 1000 1001 // --------------------- 1002 // persistent CCC writes 1003 static uint32_t att_server_persistent_ccc_tag_for_index(uint8_t index){ 1004 return ('B' << 24u) | ('T' << 16u) | ('C' << 8u) | index; 1005 } 1006 1007 static void att_server_persistent_ccc_write(hci_con_handle_t con_handle, uint16_t att_handle, uint16_t value){ 1008 // lookup att_server instance 1009 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1010 if (!hci_connection) return; 1011 att_server_t * att_server = &hci_connection->att_server; 1012 int le_device_index = att_server->ir_le_device_db_index; 1013 log_info("Store CCC value 0x%04x for handle 0x%04x of remote %s, le device id %d", value, att_handle, bd_addr_to_str(att_server->peer_address), le_device_index); 1014 1015 // check if bonded 1016 if (le_device_index < 0) return; 1017 1018 // get btstack_tlv 1019 const btstack_tlv_t * tlv_impl = NULL; 1020 void * tlv_context; 1021 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1022 if (!tlv_impl) return; 1023 1024 // update ccc tag 1025 int index; 1026 uint32_t highest_seq_nr = 0; 1027 uint32_t lowest_seq_nr = 0; 1028 uint32_t tag_for_lowest_seq_nr = 0; 1029 uint32_t tag_for_empty = 0; 1030 persistent_ccc_entry_t entry; 1031 for (index=0; index<NVN_NUM_GATT_SERVER_CCC; index++){ 1032 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1033 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1034 1035 // empty/invalid tag 1036 if (len != sizeof(persistent_ccc_entry_t)){ 1037 tag_for_empty = tag; 1038 continue; 1039 } 1040 // update highest seq nr 1041 if (entry.seq_nr > highest_seq_nr){ 1042 highest_seq_nr = entry.seq_nr; 1043 } 1044 // find entry with lowest seq nr 1045 if ((tag_for_lowest_seq_nr == 0u) || (entry.seq_nr < lowest_seq_nr)){ 1046 tag_for_lowest_seq_nr = tag; 1047 lowest_seq_nr = entry.seq_nr; 1048 } 1049 1050 if (entry.device_index != le_device_index) continue; 1051 if (entry.att_handle != att_handle) continue; 1052 1053 // found matching entry 1054 if (value != 0){ 1055 // update 1056 if (entry.value == value) { 1057 log_info("CCC Index %u: Up-to-date", index); 1058 return; 1059 } 1060 entry.value = (uint8_t) value; 1061 entry.seq_nr = highest_seq_nr + 1u; 1062 log_info("CCC Index %u: Store", index); 1063 int result = tlv_impl->store_tag(tlv_context, tag, (const uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1064 if (result != 0){ 1065 log_error("Store tag index %u failed", index); 1066 } 1067 } else { 1068 // delete 1069 log_info("CCC Index %u: Delete", index); 1070 tlv_impl->delete_tag(tlv_context, tag); 1071 } 1072 return; 1073 } 1074 1075 log_info("tag_for_empty %"PRIx32", tag_for_lowest_seq_nr %"PRIx32, tag_for_empty, tag_for_lowest_seq_nr); 1076 1077 if (value == 0u){ 1078 // done 1079 return; 1080 } 1081 1082 uint32_t tag_to_use = 0u; 1083 if (tag_for_empty != 0u){ 1084 tag_to_use = tag_for_empty; 1085 } else if (tag_for_lowest_seq_nr){ 1086 tag_to_use = tag_for_lowest_seq_nr; 1087 } else { 1088 // should not happen 1089 return; 1090 } 1091 // store ccc tag 1092 entry.seq_nr = highest_seq_nr + 1u; 1093 entry.device_index = le_device_index; 1094 entry.att_handle = att_handle; 1095 entry.value = (uint8_t) value; 1096 int result = tlv_impl->store_tag(tlv_context, tag_to_use, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1097 if (result != 0){ 1098 log_error("Store tag index %u failed", index); 1099 } 1100 } 1101 1102 static void att_server_persistent_ccc_clear(att_server_t * att_server){ 1103 int le_device_index = att_server->ir_le_device_db_index; 1104 log_info("Clear CCC values of remote %s, le device id %d", bd_addr_to_str(att_server->peer_address), le_device_index); 1105 // check if bonded 1106 if (le_device_index < 0) return; 1107 // get btstack_tlv 1108 const btstack_tlv_t * tlv_impl = NULL; 1109 void * tlv_context; 1110 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1111 if (!tlv_impl) return; 1112 // get all ccc tag 1113 int index; 1114 persistent_ccc_entry_t entry; 1115 for (index=0;index<NVN_NUM_GATT_SERVER_CCC;index++){ 1116 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1117 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1118 if (len != sizeof(persistent_ccc_entry_t)) continue; 1119 if (entry.device_index != le_device_index) continue; 1120 // delete entry 1121 log_info("CCC Index %u: Delete", index); 1122 tlv_impl->delete_tag(tlv_context, tag); 1123 } 1124 } 1125 1126 static void att_server_persistent_ccc_restore(att_server_t * att_server, att_connection_t * att_connection){ 1127 int le_device_index = att_server->ir_le_device_db_index; 1128 log_info("Restore CCC values of remote %s, le device id %d", bd_addr_to_str(att_server->peer_address), le_device_index); 1129 // check if bonded 1130 if (le_device_index < 0) return; 1131 // get btstack_tlv 1132 const btstack_tlv_t * tlv_impl = NULL; 1133 void * tlv_context; 1134 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1135 if (!tlv_impl) return; 1136 // get all ccc tag 1137 int index; 1138 persistent_ccc_entry_t entry; 1139 for (index=0;index<NVN_NUM_GATT_SERVER_CCC;index++){ 1140 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1141 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1142 if (len != sizeof(persistent_ccc_entry_t)) continue; 1143 if (entry.device_index != le_device_index) continue; 1144 // simulate write callback 1145 uint16_t attribute_handle = entry.att_handle; 1146 uint8_t value[2]; 1147 little_endian_store_16(value, 0, entry.value); 1148 att_write_callback_t callback = att_server_write_callback_for_handle(attribute_handle); 1149 if (!callback) continue; 1150 log_info("CCC Index %u: Set Attribute handle 0x%04x to value 0x%04x", index, attribute_handle, entry.value ); 1151 (*callback)(att_connection->con_handle, attribute_handle, ATT_TRANSACTION_MODE_NONE, 0, value, sizeof(value)); 1152 } 1153 } 1154 1155 // persistent CCC writes 1156 // --------------------- 1157 1158 // gatt service management 1159 static att_service_handler_t * att_service_handler_for_handle(uint16_t handle){ 1160 btstack_linked_list_iterator_t it; 1161 btstack_linked_list_iterator_init(&it, &service_handlers); 1162 while (btstack_linked_list_iterator_has_next(&it)){ 1163 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1164 if (handler->start_handle > handle) continue; 1165 if (handler->end_handle < handle) continue; 1166 return handler; 1167 } 1168 return NULL; 1169 } 1170 static att_read_callback_t att_server_read_callback_for_handle(uint16_t handle){ 1171 att_service_handler_t * handler = att_service_handler_for_handle(handle); 1172 if (handler != NULL) return handler->read_callback; 1173 return att_server_client_read_callback; 1174 } 1175 1176 static att_write_callback_t att_server_write_callback_for_handle(uint16_t handle){ 1177 att_service_handler_t * handler = att_service_handler_for_handle(handle); 1178 if (handler != NULL) return handler->write_callback; 1179 return att_server_client_write_callback; 1180 } 1181 1182 static btstack_packet_handler_t att_server_packet_handler_for_handle(uint16_t handle){ 1183 att_service_handler_t * handler = att_service_handler_for_handle(handle); 1184 if (handler != NULL) return handler->packet_handler; 1185 return att_client_packet_handler; 1186 } 1187 1188 static void att_notify_write_callbacks(hci_con_handle_t con_handle, uint16_t transaction_mode){ 1189 // notify all callbacks 1190 btstack_linked_list_iterator_t it; 1191 btstack_linked_list_iterator_init(&it, &service_handlers); 1192 while (btstack_linked_list_iterator_has_next(&it)){ 1193 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1194 if (!handler->write_callback) continue; 1195 (*handler->write_callback)(con_handle, 0, transaction_mode, 0, NULL, 0); 1196 } 1197 if (!att_server_client_write_callback) return; 1198 (*att_server_client_write_callback)(con_handle, 0, transaction_mode, 0, NULL, 0); 1199 } 1200 1201 // returns first reported error or 0 1202 static uint8_t att_validate_prepared_write(hci_con_handle_t con_handle){ 1203 btstack_linked_list_iterator_t it; 1204 btstack_linked_list_iterator_init(&it, &service_handlers); 1205 while (btstack_linked_list_iterator_has_next(&it)){ 1206 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1207 if (!handler->write_callback) continue; 1208 uint8_t error_code = (*handler->write_callback)(con_handle, 0, ATT_TRANSACTION_MODE_VALIDATE, 0, NULL, 0); 1209 if (error_code != 0u) return error_code; 1210 } 1211 if (!att_server_client_write_callback) return 0; 1212 return (*att_server_client_write_callback)(con_handle, 0, ATT_TRANSACTION_MODE_VALIDATE, 0, NULL, 0); 1213 } 1214 1215 static uint16_t att_server_read_callback(hci_con_handle_t con_handle, uint16_t attribute_handle, uint16_t offset, uint8_t * buffer, uint16_t buffer_size){ 1216 att_read_callback_t callback = att_server_read_callback_for_handle(attribute_handle); 1217 if (!callback) return 0; 1218 return (*callback)(con_handle, attribute_handle, offset, buffer, buffer_size); 1219 } 1220 1221 static int att_server_write_callback(hci_con_handle_t con_handle, uint16_t attribute_handle, uint16_t transaction_mode, uint16_t offset, uint8_t *buffer, uint16_t buffer_size){ 1222 switch (transaction_mode){ 1223 case ATT_TRANSACTION_MODE_VALIDATE: 1224 return att_validate_prepared_write(con_handle); 1225 case ATT_TRANSACTION_MODE_EXECUTE: 1226 case ATT_TRANSACTION_MODE_CANCEL: 1227 att_notify_write_callbacks(con_handle, transaction_mode); 1228 return 0; 1229 default: 1230 break; 1231 } 1232 1233 // track CCC writes 1234 if (att_is_persistent_ccc(attribute_handle) && (offset == 0u) && (buffer_size == 2u)){ 1235 att_server_persistent_ccc_write(con_handle, attribute_handle, little_endian_read_16(buffer, 0)); 1236 } 1237 1238 att_write_callback_t callback = att_server_write_callback_for_handle(attribute_handle); 1239 if (!callback) return 0; 1240 return (*callback)(con_handle, attribute_handle, transaction_mode, offset, buffer, buffer_size); 1241 } 1242 1243 /** 1244 * @brief register read/write callbacks for specific handle range 1245 * @param att_service_handler_t 1246 */ 1247 void att_server_register_service_handler(att_service_handler_t * handler){ 1248 bool att_server_registered = false; 1249 if (att_service_handler_for_handle(handler->start_handle)){ 1250 att_server_registered = true; 1251 } 1252 1253 if (att_service_handler_for_handle(handler->end_handle)){ 1254 att_server_registered = true; 1255 } 1256 1257 if (att_server_registered){ 1258 log_error("handler for range 0x%04x-0x%04x already registered", handler->start_handle, handler->end_handle); 1259 return; 1260 } 1261 btstack_linked_list_add(&service_handlers, (btstack_linked_item_t*) handler); 1262 } 1263 1264 void att_server_init(uint8_t const * db, att_read_callback_t read_callback, att_write_callback_t write_callback){ 1265 1266 // store callbacks 1267 att_server_client_read_callback = read_callback; 1268 att_server_client_write_callback = write_callback; 1269 1270 // register for HCI Events 1271 hci_event_callback_registration.callback = &att_event_packet_handler; 1272 hci_add_event_handler(&hci_event_callback_registration); 1273 1274 // register for SM events 1275 sm_event_callback_registration.callback = &att_event_packet_handler; 1276 sm_add_event_handler(&sm_event_callback_registration); 1277 1278 // and L2CAP ATT Server PDUs 1279 att_dispatch_register_server(att_packet_handler); 1280 1281 #ifdef ENABLE_GATT_OVER_CLASSIC 1282 // setup l2cap service 1283 att_dispatch_classic_register_service(); 1284 #endif 1285 1286 att_set_db(db); 1287 att_set_read_callback(att_server_read_callback); 1288 att_set_write_callback(att_server_write_callback); 1289 } 1290 1291 void att_server_register_packet_handler(btstack_packet_handler_t handler){ 1292 att_client_packet_handler = handler; 1293 } 1294 1295 1296 // to be deprecated 1297 int att_server_can_send_packet_now(hci_con_handle_t con_handle){ 1298 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1299 if (!hci_connection) return 0; 1300 att_server_t * att_server = &hci_connection->att_server; 1301 att_connection_t * att_connection = &hci_connection->att_connection; 1302 return att_server_can_send_packet(att_server, att_connection); 1303 } 1304 1305 uint8_t att_server_register_can_send_now_callback(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1306 return att_server_request_to_send_notification(callback_registration, con_handle); 1307 } 1308 1309 void att_server_request_can_send_now_event(hci_con_handle_t con_handle){ 1310 att_client_waiting_for_can_send_registration.callback = &att_emit_can_send_now_event; 1311 att_server_request_to_send_notification(&att_client_waiting_for_can_send_registration, con_handle); 1312 } 1313 // end of deprecated 1314 1315 uint8_t att_server_request_to_send_notification(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1316 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1317 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1318 att_server_t * att_server = &hci_connection->att_server; 1319 att_connection_t * att_connection = &hci_connection->att_connection; 1320 bool added = btstack_linked_list_add_tail(&att_server->notification_requests, (btstack_linked_item_t*) callback_registration); 1321 att_server_request_can_send_now(att_server, att_connection); 1322 if (added){ 1323 return ERROR_CODE_SUCCESS; 1324 } else { 1325 return ERROR_CODE_COMMAND_DISALLOWED; 1326 } 1327 } 1328 1329 uint8_t att_server_request_to_send_indication(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1330 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1331 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1332 att_server_t * att_server = &hci_connection->att_server; 1333 att_connection_t * att_connection = &hci_connection->att_connection; 1334 bool added = btstack_linked_list_add_tail(&att_server->indication_requests, (btstack_linked_item_t*) callback_registration); 1335 att_server_request_can_send_now(att_server, att_connection); 1336 if (added){ 1337 return ERROR_CODE_SUCCESS; 1338 } else { 1339 return ERROR_CODE_COMMAND_DISALLOWED; 1340 } 1341 } 1342 1343 static uint8_t att_server_prepare_server_message(hci_con_handle_t con_handle, att_server_t ** out_att_server, att_connection_t ** out_att_connection, uint8_t ** out_packet_buffer){ 1344 1345 att_server_t * att_server = NULL; 1346 att_connection_t * att_connection = NULL; 1347 uint8_t * packet_buffer = NULL; 1348 1349 // prefer enhanced bearer 1350 #ifdef ENABLE_GATT_OVER_EATT 1351 att_server_eatt_bearer_t * eatt_bearer = att_server_eatt_bearer_for_con_handle(con_handle); 1352 if (eatt_bearer != NULL){ 1353 att_server = &eatt_bearer->att_server; 1354 att_connection = &eatt_bearer->att_connection; 1355 packet_buffer = eatt_bearer->send_buffer; 1356 } else 1357 #endif 1358 { 1359 hci_connection_t *hci_connection = hci_connection_for_handle(con_handle); 1360 if (hci_connection != NULL) { 1361 att_server = &hci_connection->att_server; 1362 att_connection = &hci_connection->att_connection; 1363 } 1364 } 1365 1366 if (att_server == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1367 if (!att_server_can_send_packet(att_server, att_connection)) return BTSTACK_ACL_BUFFERS_FULL; 1368 1369 if (packet_buffer == NULL){ 1370 l2cap_reserve_packet_buffer(); 1371 packet_buffer = l2cap_get_outgoing_buffer(); 1372 } 1373 1374 *out_att_connection = att_connection; 1375 *out_att_server = att_server; 1376 *out_packet_buffer = packet_buffer; 1377 return ERROR_CODE_SUCCESS; 1378 } 1379 1380 uint8_t att_server_notify(hci_con_handle_t con_handle, uint16_t attribute_handle, const uint8_t *value, uint16_t value_len){ 1381 att_server_t * att_server = NULL; 1382 att_connection_t * att_connection = NULL; 1383 uint8_t * packet_buffer = NULL; 1384 1385 uint8_t status = att_server_prepare_server_message(con_handle, &att_server, &att_connection, &packet_buffer); 1386 if (status != ERROR_CODE_SUCCESS){ 1387 return status; 1388 } 1389 1390 uint16_t size = att_prepare_handle_value_notification(att_connection, attribute_handle, value, value_len, packet_buffer); 1391 1392 return att_server_send_prepared(att_server, att_connection, NULL, size); 1393 } 1394 1395 /** 1396 * @brief notify client about multiple attribute value changes 1397 * @param con_handle 1398 * @param num_attributes 1399 * @param attribute_handles[] 1400 * @param values_data[] 1401 * @param values_len[] 1402 * @return 0 if ok, error otherwise 1403 */ 1404 uint8_t att_server_multiple_notify(hci_con_handle_t con_handle, uint8_t num_attributes, 1405 const uint16_t * attribute_handles, const uint8_t ** values_data, const uint16_t * values_len){ 1406 1407 att_server_t * att_server = NULL; 1408 att_connection_t * att_connection = NULL; 1409 uint8_t * packet_buffer = NULL; 1410 1411 uint8_t status = att_server_prepare_server_message(con_handle, &att_server, &att_connection, &packet_buffer); 1412 if (status != ERROR_CODE_SUCCESS){ 1413 return status; 1414 } 1415 1416 uint16_t size = att_prepare_handle_value_multiple_notification(att_connection, num_attributes, attribute_handles, values_data, values_len, packet_buffer); 1417 1418 return att_server_send_prepared(att_server, att_connection, packet_buffer, size); 1419 } 1420 1421 uint8_t att_server_indicate(hci_con_handle_t con_handle, uint16_t attribute_handle, const uint8_t *value, uint16_t value_len){ 1422 1423 att_server_t * att_server = NULL; 1424 att_connection_t * att_connection = NULL; 1425 uint8_t * packet_buffer = NULL; 1426 1427 uint8_t status = att_server_prepare_server_message(con_handle, &att_server, &att_connection, &packet_buffer); 1428 if (status != ERROR_CODE_SUCCESS){ 1429 return status; 1430 } 1431 1432 if (att_server->value_indication_handle != 0u) { 1433 // free reserved packet buffer 1434 if (att_server->bearer_type == ATT_BEARER_ENHANCED_LE){ 1435 l2cap_release_packet_buffer(); 1436 } 1437 return ATT_HANDLE_VALUE_INDICATION_IN_PROGRESS; 1438 } 1439 1440 // track indication 1441 att_server->value_indication_handle = attribute_handle; 1442 btstack_run_loop_set_timer_handler(&att_server->value_indication_timer, att_handle_value_indication_timeout); 1443 btstack_run_loop_set_timer(&att_server->value_indication_timer, ATT_TRANSACTION_TIMEOUT_MS); 1444 btstack_run_loop_add_timer(&att_server->value_indication_timer); 1445 1446 uint16_t size = att_prepare_handle_value_indication(att_connection, attribute_handle, value, value_len, packet_buffer); 1447 1448 return att_server_send_prepared(att_server, att_connection, NULL, size); 1449 } 1450 1451 uint16_t att_server_get_mtu(hci_con_handle_t con_handle){ 1452 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1453 if (!hci_connection) return 0; 1454 att_connection_t * att_connection = &hci_connection->att_connection; 1455 return att_connection->mtu; 1456 } 1457 1458 void att_server_deinit(void){ 1459 att_server_client_read_callback = NULL; 1460 att_server_client_write_callback = NULL; 1461 att_client_packet_handler = NULL; 1462 service_handlers = NULL; 1463 } 1464 1465 #ifdef ENABLE_GATT_OVER_EATT 1466 1467 #define MAX_NR_EATT_CHANNELS 5 1468 1469 static uint16_t att_server_eatt_receive_buffer_size; 1470 static uint16_t att_server_eatt_send_buffer_size; 1471 1472 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_cid(uint16_t cid){ 1473 btstack_linked_list_iterator_t it; 1474 btstack_linked_list_iterator_init(&it, &att_server_eatt_bearer_active); 1475 while(btstack_linked_list_iterator_has_next(&it)){ 1476 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) btstack_linked_list_iterator_next(&it); 1477 if (eatt_bearer->att_server.l2cap_cid == cid) { 1478 return eatt_bearer; 1479 } 1480 } 1481 return NULL; 1482 } 1483 1484 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_con_handle(hci_con_handle_t con_handle){ 1485 btstack_linked_list_iterator_t it; 1486 btstack_linked_list_iterator_init(&it, &att_server_eatt_bearer_active); 1487 while(btstack_linked_list_iterator_has_next(&it)){ 1488 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) btstack_linked_list_iterator_next(&it); 1489 if (eatt_bearer->att_connection.con_handle == con_handle) { 1490 return eatt_bearer; 1491 } 1492 } 1493 return NULL; 1494 } 1495 1496 static void att_server_eatt_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 1497 uint16_t cid; 1498 uint8_t status; 1499 uint16_t remote_mtu; 1500 1501 uint8_t i; 1502 uint8_t num_requested_bearers; 1503 uint8_t num_accepted_bearers; 1504 uint16_t initial_credits = L2CAP_LE_AUTOMATIC_CREDITS; 1505 uint8_t * receive_buffers[MAX_NR_EATT_CHANNELS]; 1506 uint16_t cids[MAX_NR_EATT_CHANNELS]; 1507 att_server_eatt_bearer_t * eatt_bearers[MAX_NR_EATT_CHANNELS]; 1508 att_server_eatt_bearer_t * eatt_bearer; 1509 att_server_t * att_server; 1510 att_connection_t * att_connection; 1511 1512 switch (packet_type) { 1513 1514 case L2CAP_DATA_PACKET: 1515 eatt_bearer = att_server_eatt_bearer_for_cid(channel); 1516 btstack_assert(eatt_bearer != NULL); 1517 att_server = &eatt_bearer->att_server; 1518 att_connection = &eatt_bearer->att_connection; 1519 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1520 break; 1521 1522 case HCI_EVENT_PACKET: 1523 switch (packet[0]) { 1524 1525 case L2CAP_EVENT_CAN_SEND_NOW: 1526 cid = l2cap_event_packet_sent_get_local_cid(packet); 1527 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1528 btstack_assert(eatt_bearer != NULL); 1529 att_server = &eatt_bearer->att_server; 1530 att_connection = &eatt_bearer->att_connection; 1531 // only used for EATT request responses 1532 btstack_assert(att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED); 1533 att_server_process_validated_request(att_server, att_connection, eatt_bearer->send_buffer); 1534 break; 1535 1536 case L2CAP_EVENT_PACKET_SENT: 1537 cid = l2cap_event_packet_sent_get_local_cid(packet); 1538 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1539 btstack_assert(eatt_bearer != NULL); 1540 att_server = &eatt_bearer->att_server; 1541 att_connection = &eatt_bearer->att_connection; 1542 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1543 break; 1544 1545 case L2CAP_EVENT_ECBM_INCOMING_CONNECTION: 1546 cid = l2cap_event_ecbm_incoming_connection_get_local_cid(packet); 1547 num_requested_bearers = l2cap_event_ecbm_incoming_connection_get_num_channels(packet); 1548 for (i = 0; i < num_requested_bearers; i++){ 1549 eatt_bearers[i] = (att_server_eatt_bearer_t *) btstack_linked_list_pop(&att_server_eatt_bearer_pool); 1550 if (eatt_bearers[i] == NULL) { 1551 break; 1552 } 1553 eatt_bearers[i]->att_connection.con_handle = l2cap_event_ecbm_incoming_connection_get_handle(packet); 1554 eatt_bearers[i]->att_server.bearer_type = ATT_BEARER_ENHANCED_LE; 1555 receive_buffers[i] = eatt_bearers[i]->receive_buffer; 1556 btstack_linked_list_add(&att_server_eatt_bearer_active, (btstack_linked_item_t *) eatt_bearers[i]); 1557 } 1558 num_accepted_bearers = i; 1559 status = l2cap_ecbm_accept_channels(cid, num_accepted_bearers, initial_credits, att_server_eatt_receive_buffer_size, receive_buffers, cids); 1560 btstack_assert(status == ERROR_CODE_SUCCESS); 1561 log_info("requested %u, accepted %u", num_requested_bearers, num_accepted_bearers); 1562 for (i=0;i<num_accepted_bearers;i++){ 1563 log_info("eatt l2cap cid: 0x%04x", cids[i]); 1564 eatt_bearers[i]->att_server.l2cap_cid = cids[i]; 1565 } 1566 break; 1567 1568 case L2CAP_EVENT_ECBM_CHANNEL_OPENED: 1569 cid = l2cap_event_ecbm_channel_opened_get_local_cid(packet); 1570 status = l2cap_event_ecbm_channel_opened_get_status(packet); 1571 remote_mtu = l2cap_event_ecbm_channel_opened_get_remote_mtu(packet); 1572 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1573 btstack_assert(eatt_bearer != NULL); 1574 eatt_bearer->att_connection.mtu_exchanged = true; 1575 eatt_bearer->att_connection.mtu = remote_mtu; 1576 eatt_bearer->att_connection.max_mtu = remote_mtu; 1577 log_info("L2CAP_EVENT_ECBM_CHANNEL_OPENED - cid 0x%04x mtu %u, status 0x%02x", cid, remote_mtu, status); 1578 break; 1579 1580 case L2CAP_EVENT_ECBM_RECONFIGURED: 1581 break; 1582 1583 case L2CAP_EVENT_CHANNEL_CLOSED: 1584 eatt_bearer = att_server_eatt_bearer_for_cid(l2cap_event_channel_closed_get_local_cid(packet)); 1585 btstack_assert(eatt_bearers != NULL); 1586 1587 // TODO: finalize - abort queued writes 1588 1589 btstack_linked_list_remove(&att_server_eatt_bearer_active, (btstack_linked_item_t *) eatt_bearer); 1590 btstack_linked_list_add(&att_server_eatt_bearer_pool, (btstack_linked_item_t *) eatt_bearer); 1591 break; 1592 default: 1593 break; 1594 } 1595 break; 1596 default: 1597 btstack_unreachable(); 1598 break; 1599 } 1600 } 1601 1602 // create eatt bearers 1603 uint8_t att_server_eatt_init(uint8_t num_eatt_bearers, uint8_t * storage_buffer, uint16_t storage_size){ 1604 uint16_t size_for_structs = num_eatt_bearers * sizeof(att_server_eatt_bearer_t); 1605 if (storage_size < size_for_structs) { 1606 return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED; 1607 } 1608 1609 // TODO: The minimum ATT_MTU for an Enhanced ATT bearer is 64 octets. 1610 1611 memset(storage_buffer, 0, storage_size); 1612 uint16_t buffer_size_per_bearer = ((storage_size - size_for_structs) / num_eatt_bearers); 1613 att_server_eatt_receive_buffer_size = buffer_size_per_bearer / 2; 1614 att_server_eatt_send_buffer_size = buffer_size_per_bearer / 2; 1615 uint8_t * bearer_buffer = &storage_buffer[size_for_structs]; 1616 uint8_t i; 1617 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) storage_buffer; 1618 log_info("%u EATT bearers with receive buffer size %u", 1619 num_eatt_bearers, att_server_eatt_receive_buffer_size); 1620 for (i=0;i<num_eatt_bearers;i++){ 1621 eatt_bearer->att_connection.con_handle = HCI_CON_HANDLE_INVALID; 1622 eatt_bearer->receive_buffer = bearer_buffer; 1623 bearer_buffer += att_server_eatt_receive_buffer_size; 1624 eatt_bearer->send_buffer = bearer_buffer; 1625 bearer_buffer += att_server_eatt_send_buffer_size; 1626 btstack_linked_list_add(&att_server_eatt_bearer_pool, (btstack_linked_item_t *) eatt_bearer); 1627 eatt_bearer++; 1628 } 1629 // TODO: define minimum EATT MTU 1630 l2cap_ecbm_register_service(att_server_eatt_handler, BLUETOOTH_PSM_EATT, 64, 0, false); 1631 1632 return 0; 1633 } 1634 #endif