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 #define ATT_SERVICE_FLAGS_DELAYED_RESPONSE (1<<0u) 81 82 static void att_run_for_context(att_server_t * att_server, att_connection_t * att_connection); 83 static att_write_callback_t att_server_write_callback_for_handle(uint16_t handle); 84 static btstack_packet_handler_t att_server_packet_handler_for_handle(uint16_t handle); 85 static void att_server_handle_can_send_now(void); 86 static void att_server_persistent_ccc_restore(att_server_t * att_server, att_connection_t * att_connection); 87 static void att_server_persistent_ccc_clear(att_server_t * att_server); 88 static void att_server_handle_att_pdu(att_server_t * att_server, att_connection_t * att_connection, uint8_t * packet, uint16_t size); 89 90 typedef enum { 91 ATT_SERVER_RUN_PHASE_1_REQUESTS = 0, 92 ATT_SERVER_RUN_PHASE_2_INDICATIONS, 93 ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS, 94 } att_server_run_phase_t; 95 96 // 97 typedef struct { 98 uint32_t seq_nr; 99 uint16_t att_handle; 100 uint8_t value; 101 uint8_t device_index; 102 } persistent_ccc_entry_t; 103 104 // global 105 static btstack_packet_callback_registration_t hci_event_callback_registration; 106 static btstack_packet_callback_registration_t sm_event_callback_registration; 107 static btstack_packet_handler_t att_client_packet_handler; 108 static btstack_linked_list_t service_handlers; 109 static btstack_context_callback_registration_t att_client_waiting_for_can_send_registration; 110 111 static att_read_callback_t att_server_client_read_callback; 112 static att_write_callback_t att_server_client_write_callback; 113 114 // round robin 115 static hci_con_handle_t att_server_last_can_send_now = HCI_CON_HANDLE_INVALID; 116 117 static uint8_t att_server_flags; 118 119 #ifdef ENABLE_GATT_OVER_EATT 120 typedef struct { 121 btstack_linked_item_t item; 122 att_server_t att_server; 123 att_connection_t att_connection; 124 uint8_t * receive_buffer; 125 uint8_t * send_buffer; 126 } att_server_eatt_bearer_t; 127 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_con_handle(hci_con_handle_t con_handle); 128 static btstack_linked_list_t att_server_eatt_bearer_pool; 129 static btstack_linked_list_t att_server_eatt_bearer_active; 130 #endif 131 132 #ifdef ENABLE_LE_SIGNED_WRITE 133 static bool att_server_connections_for_state(att_server_state_t state, att_server_t ** att_server_out, att_connection_t ** att_connection_out){ 134 btstack_linked_list_iterator_t it; 135 hci_connections_get_iterator(&it); 136 while(btstack_linked_list_iterator_has_next(&it)){ 137 hci_connection_t * hci_connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 138 if (hci_connection->att_server.state == state) { 139 *att_server_out = &hci_connection->att_server; 140 *att_connection_out = &hci_connection->att_connection; 141 return true; 142 } 143 } 144 145 #ifdef ENABLE_GATT_OVER_EATT 146 btstack_linked_list_iterator_init(&it, &att_server_eatt_bearer_active); 147 while(btstack_linked_list_iterator_has_next(&it)){ 148 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) btstack_linked_list_iterator_next(&it); 149 if (eatt_bearer->att_server.state == state) { 150 *att_server_out = &eatt_bearer->att_server; 151 *att_connection_out = &eatt_bearer->att_connection; 152 return true; 153 } 154 } 155 #endif 156 157 return false; 158 } 159 #endif 160 161 static void att_server_request_can_send_now(att_server_t * att_server, att_connection_t * att_connection ){ 162 switch (att_server->bearer_type){ 163 case ATT_BEARER_UNENHANCED_LE: 164 #ifdef ENABLE_GATT_OVER_CLASSIC 165 case ATT_BEARER_UNENHANCED_CLASSIC: 166 /* fall through */ 167 #endif 168 att_dispatch_server_request_can_send_now_event(att_connection->con_handle); 169 break; 170 #ifdef ENABLE_GATT_OVER_EATT 171 case ATT_BEARER_ENHANCED_LE: 172 l2cap_request_can_send_now_event(att_server->l2cap_cid); 173 break; 174 #endif 175 default: 176 btstack_unreachable(); 177 break; 178 } 179 } 180 181 static bool att_server_can_send_packet(att_server_t * att_server, att_connection_t * att_connection){ 182 switch (att_server->bearer_type) { 183 case ATT_BEARER_UNENHANCED_LE: 184 #ifdef ENABLE_GATT_OVER_CLASSIC 185 case ATT_BEARER_UNENHANCED_CLASSIC: 186 /* fall through */ 187 #endif 188 return att_dispatch_server_can_send_now(att_connection->con_handle); 189 #ifdef ENABLE_GATT_OVER_EATT 190 case ATT_BEARER_ENHANCED_LE: 191 return l2cap_can_send_packet_now(att_server->l2cap_cid); 192 #endif 193 default: 194 btstack_unreachable(); 195 break; 196 } 197 return false; 198 } 199 200 static void att_handle_value_indication_notify_client(uint8_t status, uint16_t client_handle, uint16_t attribute_handle){ 201 btstack_packet_handler_t packet_handler = att_server_packet_handler_for_handle(attribute_handle); 202 if (!packet_handler) return; 203 204 uint8_t event[7]; 205 int pos = 0; 206 event[pos++] = ATT_EVENT_HANDLE_VALUE_INDICATION_COMPLETE; 207 event[pos++] = sizeof(event) - 2u; 208 event[pos++] = status; 209 little_endian_store_16(event, pos, client_handle); 210 pos += 2; 211 little_endian_store_16(event, pos, attribute_handle); 212 (*packet_handler)(HCI_EVENT_PACKET, 0, &event[0], sizeof(event)); 213 } 214 215 static void att_emit_event_to_all(const uint8_t * event, uint16_t size){ 216 // dispatch to app level handler 217 if (att_client_packet_handler != NULL){ 218 (*att_client_packet_handler)(HCI_EVENT_PACKET, 0, (uint8_t*) event, size); 219 } 220 221 // dispatch to service handlers 222 btstack_linked_list_iterator_t it; 223 btstack_linked_list_iterator_init(&it, &service_handlers); 224 while (btstack_linked_list_iterator_has_next(&it)){ 225 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 226 if (!handler->packet_handler) continue; 227 (*handler->packet_handler)(HCI_EVENT_PACKET, 0, (uint8_t*) event, size); 228 } 229 } 230 231 static void att_emit_mtu_event(hci_con_handle_t con_handle, uint16_t mtu){ 232 uint8_t event[6]; 233 int pos = 0; 234 event[pos++] = ATT_EVENT_MTU_EXCHANGE_COMPLETE; 235 event[pos++] = sizeof(event) - 2u; 236 little_endian_store_16(event, pos, con_handle); 237 pos += 2; 238 little_endian_store_16(event, pos, mtu); 239 240 // also dispatch to GATT Clients 241 att_dispatch_server_mtu_exchanged(con_handle, mtu); 242 243 // dispatch to app level handler and service handlers 244 att_emit_event_to_all(&event[0], sizeof(event)); 245 } 246 247 static void att_emit_can_send_now_event(void * context){ 248 UNUSED(context); 249 if (!att_client_packet_handler) return; 250 251 uint8_t event[] = { ATT_EVENT_CAN_SEND_NOW, 0}; 252 (*att_client_packet_handler)(HCI_EVENT_PACKET, 0, &event[0], sizeof(event)); 253 } 254 255 static void att_emit_connected_event(att_server_t * att_server, att_connection_t * att_connection){ 256 uint8_t event[11]; 257 int pos = 0; 258 event[pos++] = ATT_EVENT_CONNECTED; 259 event[pos++] = sizeof(event) - 2u; 260 event[pos++] = att_server->peer_addr_type; 261 reverse_bd_addr(att_server->peer_address, &event[pos]); 262 pos += 6; 263 little_endian_store_16(event, pos, att_connection->con_handle); 264 pos += 2; 265 266 // dispatch to app level handler and service handlers 267 att_emit_event_to_all(&event[0], sizeof(event)); 268 } 269 270 271 static void att_emit_disconnected_event(uint16_t con_handle){ 272 uint8_t event[4]; 273 int pos = 0; 274 event[pos++] = ATT_EVENT_DISCONNECTED; 275 event[pos++] = sizeof(event) - 2u; 276 little_endian_store_16(event, pos, con_handle); 277 pos += 2; 278 279 // dispatch to app level handler and service handlers 280 att_emit_event_to_all(&event[0], sizeof(event)); 281 } 282 283 static void att_handle_value_indication_timeout(btstack_timer_source_t *ts){ 284 void * context = btstack_run_loop_get_timer_context(ts); 285 hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) context; 286 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 287 if (!hci_connection) return; 288 // @note: after a transaction timeout, no more requests shall be sent over this ATT Bearer 289 // (that's why we don't reset the value_indication_handle) 290 att_server_t * att_server = &hci_connection->att_server; 291 uint16_t att_handle = att_server->value_indication_handle; 292 att_connection_t * att_connection = &hci_connection->att_connection; 293 att_handle_value_indication_notify_client((uint8_t)ATT_HANDLE_VALUE_INDICATION_TIMEOUT, att_connection->con_handle, att_handle); 294 } 295 296 static void att_server_event_packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 297 298 UNUSED(channel); // ok: there is no channel 299 UNUSED(size); // ok: handling own l2cap events 300 301 att_server_t * att_server; 302 att_connection_t * att_connection; 303 hci_con_handle_t con_handle; 304 hci_connection_t * hci_connection; 305 306 switch (packet_type) { 307 308 case HCI_EVENT_PACKET: 309 switch (hci_event_packet_get_type(packet)) { 310 case HCI_EVENT_META_GAP: 311 switch (hci_event_gap_meta_get_subevent_code(packet)) { 312 case GAP_SUBEVENT_LE_CONNECTION_COMPLETE: 313 con_handle = gap_subevent_le_connection_complete_get_connection_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->peer_addr_type = gap_subevent_le_connection_complete_get_peer_address_type(packet); 319 gap_subevent_le_connection_complete_get_peer_address(packet, att_server->peer_address); 320 att_connection = &hci_connection->att_connection; 321 att_connection->con_handle = con_handle; 322 // reset connection properties 323 att_server->state = ATT_SERVER_IDLE; 324 att_server->bearer_type = ATT_BEARER_UNENHANCED_LE; 325 att_connection->mtu = ATT_DEFAULT_MTU; 326 att_connection->max_mtu = l2cap_max_le_mtu(); 327 if (att_connection->max_mtu > ATT_REQUEST_BUFFER_SIZE){ 328 att_connection->max_mtu = ATT_REQUEST_BUFFER_SIZE; 329 } 330 att_connection->encryption_key_size = 0u; 331 att_connection->authenticated = 0u; 332 att_connection->authorized = 0u; 333 // workaround: identity resolving can already be complete, at least store result 334 att_server->ir_le_device_db_index = sm_le_device_index(con_handle); 335 att_server->ir_lookup_active = false; 336 att_server->pairing_active = false; 337 // notify all - new 338 att_emit_connected_event(att_server, att_connection); 339 break; 340 default: 341 break; 342 } 343 break; 344 345 case HCI_EVENT_LE_META: 346 switch (hci_event_le_meta_get_subevent_code(packet)) { 347 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE: 348 // forward LE Connection Complete event to keep backward compatibility 349 // deprecated: please register hci handler with hci_add_event_handler or handle ATT_EVENT_CONNECTED 350 att_emit_event_to_all(packet, size); 351 break; 352 default: 353 break; 354 } 355 break; 356 357 case HCI_EVENT_ENCRYPTION_CHANGE: 358 case HCI_EVENT_ENCRYPTION_CHANGE_V2: 359 case HCI_EVENT_ENCRYPTION_KEY_REFRESH_COMPLETE: 360 // check handle 361 con_handle = little_endian_read_16(packet, 3); 362 hci_connection = hci_connection_for_handle(con_handle); 363 if (!hci_connection) break; 364 if (gap_get_connection_type(con_handle) != GAP_CONNECTION_LE) break; 365 // update security params 366 att_server = &hci_connection->att_server; 367 att_connection = &hci_connection->att_connection; 368 att_connection->encryption_key_size = gap_encryption_key_size(con_handle); 369 att_connection->authenticated = gap_authenticated(con_handle) ? 1 : 0; 370 att_connection->secure_connection = gap_secure_connection(con_handle) ? 1 : 0; 371 log_info("encrypted key size %u, authenticated %u, secure connection %u", 372 att_connection->encryption_key_size, att_connection->authenticated, att_connection->secure_connection); 373 if (hci_event_packet_get_type(packet) == HCI_EVENT_ENCRYPTION_CHANGE){ 374 // restore CCC values when encrypted for LE Connections 375 if (hci_event_encryption_change_get_encryption_enabled(packet) != 0){ 376 att_server_persistent_ccc_restore(att_server, att_connection); 377 } 378 } 379 att_run_for_context(att_server, att_connection); 380 break; 381 382 case HCI_EVENT_DISCONNECTION_COMPLETE: 383 // check handle 384 con_handle = hci_event_disconnection_complete_get_connection_handle(packet); 385 hci_connection = hci_connection_for_handle(con_handle); 386 if (!hci_connection) break; 387 att_server = &hci_connection->att_server; 388 att_connection = &hci_connection->att_connection; 389 att_clear_transaction_queue(att_connection); 390 att_connection->con_handle = 0; 391 att_server->pairing_active = false; 392 att_server->state = ATT_SERVER_IDLE; 393 if (att_server->value_indication_handle != 0u){ 394 btstack_run_loop_remove_timer(&att_server->value_indication_timer); 395 uint16_t att_handle = att_server->value_indication_handle; 396 att_server->value_indication_handle = 0u; // reset error state 397 att_handle_value_indication_notify_client((uint8_t)ATT_HANDLE_VALUE_INDICATION_DISCONNECT, att_connection->con_handle, att_handle); 398 } 399 // notify all - new 400 att_emit_disconnected_event(con_handle); 401 // notify all - old 402 att_emit_event_to_all(packet, size); 403 break; 404 405 // Identity Resolving 406 case SM_EVENT_IDENTITY_RESOLVING_STARTED: 407 con_handle = sm_event_identity_resolving_started_get_handle(packet); 408 hci_connection = hci_connection_for_handle(con_handle); 409 if (!hci_connection) break; 410 att_server = &hci_connection->att_server; 411 log_info("SM_EVENT_IDENTITY_RESOLVING_STARTED"); 412 att_server->ir_lookup_active = true; 413 break; 414 case SM_EVENT_IDENTITY_RESOLVING_SUCCEEDED: 415 con_handle = sm_event_identity_created_get_handle(packet); 416 hci_connection = hci_connection_for_handle(con_handle); 417 if (!hci_connection) return; 418 att_connection = &hci_connection->att_connection; 419 att_server = &hci_connection->att_server; 420 att_server->ir_lookup_active = false; 421 att_server->ir_le_device_db_index = sm_event_identity_resolving_succeeded_get_index(packet); 422 log_info("SM_EVENT_IDENTITY_RESOLVING_SUCCEEDED"); 423 att_run_for_context(att_server, att_connection); 424 break; 425 case SM_EVENT_IDENTITY_RESOLVING_FAILED: 426 con_handle = sm_event_identity_resolving_failed_get_handle(packet); 427 hci_connection = hci_connection_for_handle(con_handle); 428 if (!hci_connection) break; 429 att_connection = &hci_connection->att_connection; 430 att_server = &hci_connection->att_server; 431 log_info("SM_EVENT_IDENTITY_RESOLVING_FAILED"); 432 att_server->ir_lookup_active = false; 433 att_server->ir_le_device_db_index = -1; 434 att_run_for_context(att_server, att_connection); 435 break; 436 437 // Pairing started - delete stored CCC values 438 // - assumes pairing indicates either new device or re-pairing, in both cases there should be no stored CCC values 439 // - assumes that all events have the con handle as the first field 440 case SM_EVENT_JUST_WORKS_REQUEST: 441 case SM_EVENT_PASSKEY_DISPLAY_NUMBER: 442 case SM_EVENT_PASSKEY_INPUT_NUMBER: 443 case SM_EVENT_NUMERIC_COMPARISON_REQUEST: 444 con_handle = sm_event_just_works_request_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 Pairing started"); 449 att_server->pairing_active = true; 450 if (att_server->ir_le_device_db_index < 0) break; 451 att_server_persistent_ccc_clear(att_server); 452 // index not valid anymore 453 att_server->ir_le_device_db_index = -1; 454 break; 455 456 // Bonding completed 457 case SM_EVENT_IDENTITY_CREATED: 458 con_handle = sm_event_identity_created_get_handle(packet); 459 hci_connection = hci_connection_for_handle(con_handle); 460 if (!hci_connection) return; 461 att_connection = &hci_connection->att_connection; 462 att_server = &hci_connection->att_server; 463 att_server->pairing_active = false; 464 att_server->ir_le_device_db_index = sm_event_identity_created_get_index(packet); 465 att_run_for_context(att_server, att_connection); 466 break; 467 468 // Pairing complete (with/without bonding=storing of pairing information) 469 case SM_EVENT_PAIRING_COMPLETE: 470 con_handle = sm_event_pairing_complete_get_handle(packet); 471 hci_connection = hci_connection_for_handle(con_handle); 472 if (!hci_connection) return; 473 att_connection = &hci_connection->att_connection; 474 att_server = &hci_connection->att_server; 475 att_server->pairing_active = false; 476 att_run_for_context(att_server, att_connection); 477 break; 478 479 // Authorization 480 case SM_EVENT_AUTHORIZATION_RESULT: { 481 con_handle = sm_event_authorization_result_get_handle(packet); 482 hci_connection = hci_connection_for_handle(con_handle); 483 if (!hci_connection) break; 484 att_connection = &hci_connection->att_connection; 485 att_server = &hci_connection->att_server; 486 att_connection->authorized = sm_event_authorization_result_get_authorization_result(packet); 487 att_server_request_can_send_now(att_server, att_connection); 488 break; 489 } 490 default: 491 break; 492 } 493 break; 494 default: 495 break; 496 } 497 } 498 499 static uint8_t 500 att_server_send_prepared(const att_server_t *att_server, const att_connection_t *att_connection, uint8_t *buffer, 501 uint16_t size) { 502 UNUSED(buffer); 503 uint8_t status = ERROR_CODE_SUCCESS; 504 switch (att_server->bearer_type) { 505 case ATT_BEARER_UNENHANCED_LE: 506 status = l2cap_send_prepared_connectionless(att_connection->con_handle, L2CAP_CID_ATTRIBUTE_PROTOCOL, size); 507 break; 508 #ifdef ENABLE_GATT_OVER_CLASSIC 509 case ATT_BEARER_UNENHANCED_CLASSIC: 510 status = l2cap_send_prepared(att_server->l2cap_cid, size); 511 break; 512 #endif 513 #ifdef ENABLE_GATT_OVER_EATT 514 case ATT_BEARER_ENHANCED_LE: 515 btstack_assert(buffer != NULL); 516 status = l2cap_send(att_server->l2cap_cid, buffer, size); 517 break; 518 #endif 519 default: 520 btstack_unreachable(); 521 break; 522 } 523 return status; 524 } 525 526 #ifdef ENABLE_LE_SIGNED_WRITE 527 static void att_signed_write_handle_cmac_result(uint8_t hash[8]){ 528 att_server_t * att_server = NULL; 529 att_connection_t * att_connection = NULL; 530 bool found = att_server_connections_for_state(ATT_SERVER_W4_SIGNED_WRITE_VALIDATION, &att_server, &att_connection); 531 532 if (found == false){ 533 return; 534 } 535 536 uint8_t hash_flipped[8]; 537 reverse_64(hash, hash_flipped); 538 if (memcmp(hash_flipped, &att_server->request_buffer[att_server->request_size-8], 8) != 0){ 539 log_info("ATT Signed Write, invalid signature"); 540 #ifdef ENABLE_TESTING_SUPPORT 541 printf("ATT Signed Write, invalid signature\n"); 542 #endif 543 att_server->state = ATT_SERVER_IDLE; 544 return; 545 } 546 log_info("ATT Signed Write, valid signature"); 547 #ifdef ENABLE_TESTING_SUPPORT 548 printf("ATT Signed Write, valid signature\n"); 549 #endif 550 551 // update sequence number 552 uint32_t counter_packet = little_endian_read_32(att_server->request_buffer, att_server->request_size-12); 553 le_device_db_remote_counter_set(att_server->ir_le_device_db_index, counter_packet+1); 554 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 555 att_server_request_can_send_now(att_server, att_connection); 556 } 557 #endif 558 559 #ifdef ENABLE_ATT_DELAYED_RESPONSE 560 static void att_server_handle_response_pending(att_server_t *att_server, const att_connection_t *att_connection, 561 const uint8_t *eatt_buffer, 562 uint16_t att_response_size) { 563 // update state 564 att_server->state = ATT_SERVER_RESPONSE_PENDING; 565 566 // callback with handle ATT_READ_RESPONSE_PENDING for reads 567 if (att_response_size == ATT_READ_RESPONSE_PENDING){ 568 // notify services that returned response pending 569 btstack_linked_list_iterator_t it; 570 btstack_linked_list_iterator_init(&it, &service_handlers); 571 while (btstack_linked_list_iterator_has_next(&it)) { 572 att_service_handler_t *handler = (att_service_handler_t *) btstack_linked_list_iterator_next(&it); 573 if ((handler->flags & ATT_SERVICE_FLAGS_DELAYED_RESPONSE) != 0){ 574 handler->flags &= ~ATT_SERVICE_FLAGS_DELAYED_RESPONSE; 575 handler->read_callback(att_connection->con_handle, ATT_READ_RESPONSE_PENDING, 0, NULL, 0); 576 } 577 } 578 // notify main read callback if it returned response pending 579 if ((att_server_flags & ATT_SERVICE_FLAGS_DELAYED_RESPONSE) != 0){ 580 // flag was set by read callback 581 btstack_assert(att_server_client_read_callback != NULL); 582 (*att_server_client_read_callback)(att_connection->con_handle, ATT_READ_RESPONSE_PENDING, 0, NULL, 0); 583 } 584 } 585 586 // free reserved buffer - might trigger next read/write 587 if (eatt_buffer == NULL){ 588 l2cap_release_packet_buffer(); 589 } 590 } 591 #endif 592 593 // pre: att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED 594 // pre: can send now 595 // uses l2cap outgoing buffer if no eatt_buffer provided 596 // returns: 1 if packet was sent 597 static int 598 att_server_process_validated_request(att_server_t *att_server, att_connection_t *att_connection, uint8_t *eatt_buffer) { 599 600 uint8_t * att_response_buffer; 601 if (eatt_buffer != NULL){ 602 att_response_buffer = eatt_buffer; 603 } else { 604 l2cap_reserve_packet_buffer(); 605 att_response_buffer = l2cap_get_outgoing_buffer(); 606 } 607 608 uint16_t att_response_size = 0; 609 // Send Error Response for MTU Request over connection-oriented channel 610 if ((att_server->bearer_type != ATT_BEARER_UNENHANCED_LE) && (att_server->request_buffer[0] == ATT_EXCHANGE_MTU_REQUEST)){ 611 att_response_size = 5; 612 att_response_buffer[0] = ATT_ERROR_RESPONSE; 613 att_response_buffer[1] = ATT_EXCHANGE_MTU_REQUEST; 614 att_response_buffer[2] = 0; 615 att_response_buffer[3] = 0; 616 att_response_buffer[4] = ATT_ERROR_REQUEST_NOT_SUPPORTED; 617 } else { 618 att_response_size = att_handle_request(att_connection, att_server->request_buffer, att_server->request_size, att_response_buffer); 619 } 620 621 #ifdef ENABLE_ATT_DELAYED_RESPONSE 622 if ((att_response_size == ATT_READ_RESPONSE_PENDING) || (att_response_size == ATT_INTERNAL_WRITE_RESPONSE_PENDING)){ 623 att_server_handle_response_pending(att_server, att_connection, eatt_buffer, att_response_size); 624 return 0; 625 } 626 #endif 627 628 // intercept "insufficient authorization" for authenticated connections to allow for user authorization 629 if ((att_response_size >= 4u) 630 && (att_response_buffer[0] == ATT_ERROR_RESPONSE) 631 && (att_response_buffer[4] == ATT_ERROR_INSUFFICIENT_AUTHORIZATION) 632 && (att_connection->authenticated != 0u)){ 633 634 switch (gap_authorization_state(att_connection->con_handle)){ 635 case AUTHORIZATION_UNKNOWN: 636 if (eatt_buffer == NULL){ 637 l2cap_release_packet_buffer(); 638 } 639 sm_request_pairing(att_connection->con_handle); 640 return 0; 641 case AUTHORIZATION_PENDING: 642 if (eatt_buffer == NULL){ 643 l2cap_release_packet_buffer(); 644 } 645 return 0; 646 default: 647 break; 648 } 649 } 650 651 att_server->state = ATT_SERVER_IDLE; 652 if (att_response_size == 0u) { 653 if (eatt_buffer == NULL){ 654 l2cap_release_packet_buffer(); 655 } 656 return 0; 657 } 658 659 (void) att_server_send_prepared(att_server, att_connection, eatt_buffer, att_response_size); 660 661 // notify client about MTU exchange result 662 if (att_response_buffer[0] == ATT_EXCHANGE_MTU_RESPONSE){ 663 att_emit_mtu_event(att_connection->con_handle, att_connection->mtu); 664 } 665 return 1; 666 } 667 668 #ifdef ENABLE_ATT_DELAYED_RESPONSE 669 uint8_t att_server_response_ready(hci_con_handle_t con_handle){ 670 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 671 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 672 att_server_t * att_server = &hci_connection->att_server; 673 att_connection_t * att_connection = &hci_connection->att_connection; 674 if (att_server->state != ATT_SERVER_RESPONSE_PENDING) return ERROR_CODE_COMMAND_DISALLOWED; 675 676 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 677 att_server_request_can_send_now(att_server, att_connection); 678 return ERROR_CODE_SUCCESS; 679 } 680 #endif 681 682 static void att_run_for_context(att_server_t * att_server, att_connection_t * att_connection){ 683 switch (att_server->state){ 684 case ATT_SERVER_REQUEST_RECEIVED: 685 switch (att_server->bearer_type){ 686 case ATT_BEARER_UNENHANCED_LE: 687 // wait until re-encryption as central is complete 688 if (gap_reconnect_security_setup_active(att_connection->con_handle)) { 689 return; 690 }; 691 break; 692 #if defined(ENABLE_GATT_OVER_CLASSIC) || defined (ENABLE_GATT_OVER_EATT) 693 #ifdef ENABLE_GATT_OVER_CLASSIC 694 case ATT_BEARER_UNENHANCED_CLASSIC: 695 /* fall through */ 696 #endif 697 #ifdef ENABLE_GATT_OVER_EATT 698 case ATT_BEARER_ENHANCED_LE: 699 #endif 700 // ok 701 break; 702 #endif 703 default: 704 btstack_unreachable(); 705 break; 706 } 707 708 // wait until pairing is complete 709 if (att_server->pairing_active) break; 710 711 #ifdef ENABLE_LE_SIGNED_WRITE 712 if (att_server->request_buffer[0] == ATT_SIGNED_WRITE_COMMAND){ 713 log_info("ATT Signed Write!"); 714 if (!sm_cmac_ready()) { 715 log_info("ATT Signed Write, sm_cmac engine not ready. Abort"); 716 att_server->state = ATT_SERVER_IDLE; 717 return; 718 } 719 if (att_server->request_size < (3 + 12)) { 720 log_info("ATT Signed Write, request to short. Abort."); 721 att_server->state = ATT_SERVER_IDLE; 722 return; 723 } 724 if (att_server->ir_lookup_active){ 725 return; 726 } 727 if (att_server->ir_le_device_db_index < 0){ 728 log_info("ATT Signed Write, CSRK not available"); 729 att_server->state = ATT_SERVER_IDLE; 730 return; 731 } 732 733 // check counter 734 uint32_t counter_packet = little_endian_read_32(att_server->request_buffer, att_server->request_size-12); 735 uint32_t counter_db = le_device_db_remote_counter_get(att_server->ir_le_device_db_index); 736 log_info("ATT Signed Write, DB counter %"PRIu32", packet counter %"PRIu32, counter_db, counter_packet); 737 if (counter_packet < counter_db){ 738 log_info("ATT Signed Write, db reports higher counter, abort"); 739 att_server->state = ATT_SERVER_IDLE; 740 return; 741 } 742 743 // signature is { sequence counter, secure hash } 744 sm_key_t csrk; 745 le_device_db_remote_csrk_get(att_server->ir_le_device_db_index, csrk); 746 att_server->state = ATT_SERVER_W4_SIGNED_WRITE_VALIDATION; 747 log_info("Orig Signature: "); 748 log_info_hexdump( &att_server->request_buffer[att_server->request_size-8], 8); 749 uint16_t attribute_handle = little_endian_read_16(att_server->request_buffer, 1); 750 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); 751 return; 752 } 753 #endif 754 // move on 755 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 756 att_server_request_can_send_now(att_server, att_connection); 757 break; 758 759 default: 760 break; 761 } 762 } 763 764 static bool att_server_data_ready_for_phase(att_server_t * att_server, att_server_run_phase_t phase){ 765 switch (phase){ 766 case ATT_SERVER_RUN_PHASE_1_REQUESTS: 767 return att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 768 case ATT_SERVER_RUN_PHASE_2_INDICATIONS: 769 return (!btstack_linked_list_empty(&att_server->indication_requests) && (att_server->value_indication_handle == 0u)); 770 case ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS: 771 return (!btstack_linked_list_empty(&att_server->notification_requests)); 772 default: 773 btstack_assert(false); 774 return false; 775 } 776 } 777 778 static void att_server_trigger_send_for_phase(att_server_t * att_server, att_connection_t * att_connection, att_server_run_phase_t phase){ 779 btstack_context_callback_registration_t * client; 780 switch (phase){ 781 case ATT_SERVER_RUN_PHASE_1_REQUESTS: 782 att_server_process_validated_request(att_server, att_connection, NULL); 783 break; 784 case ATT_SERVER_RUN_PHASE_2_INDICATIONS: 785 client = (btstack_context_callback_registration_t*) att_server->indication_requests; 786 btstack_linked_list_remove(&att_server->indication_requests, (btstack_linked_item_t *) client); 787 client->callback(client->context); 788 break; 789 case ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS: 790 client = (btstack_context_callback_registration_t*) att_server->notification_requests; 791 btstack_linked_list_remove(&att_server->notification_requests, (btstack_linked_item_t *) client); 792 client->callback(client->context); 793 break; 794 default: 795 btstack_assert(false); 796 break; 797 } 798 } 799 800 static void att_server_handle_can_send_now(void){ 801 802 hci_con_handle_t last_send_con_handle = HCI_CON_HANDLE_INVALID; 803 hci_connection_t * request_hci_connection = NULL; 804 bool can_send_now = true; 805 uint8_t phase_index; 806 807 for (phase_index = ATT_SERVER_RUN_PHASE_1_REQUESTS; phase_index <= ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS; phase_index++){ 808 att_server_run_phase_t phase = (att_server_run_phase_t) phase_index; 809 hci_con_handle_t skip_connections_until = att_server_last_can_send_now; 810 while (true){ 811 btstack_linked_list_iterator_t it; 812 hci_connections_get_iterator(&it); 813 while(btstack_linked_list_iterator_has_next(&it)){ 814 hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 815 att_server_t * att_server = &connection->att_server; 816 att_connection_t * att_connection = &connection->att_connection; 817 818 bool data_ready = att_server_data_ready_for_phase(att_server, phase); 819 820 // log_debug("phase %u, handle 0x%04x, skip until 0x%04x, data ready %u", phase, att_connection->con_handle, skip_connections_until, data_ready); 821 822 // skip until last sender found (which is also skipped) 823 if (skip_connections_until != HCI_CON_HANDLE_INVALID){ 824 if (data_ready && (request_hci_connection == NULL)){ 825 request_hci_connection = connection; 826 } 827 if (skip_connections_until == att_connection->con_handle){ 828 skip_connections_until = HCI_CON_HANDLE_INVALID; 829 } 830 continue; 831 }; 832 833 if (data_ready){ 834 if (can_send_now){ 835 att_server_trigger_send_for_phase(att_server, att_connection, phase); 836 last_send_con_handle = att_connection->con_handle; 837 can_send_now = att_server_can_send_packet(att_server, att_connection); 838 data_ready = att_server_data_ready_for_phase(att_server, phase); 839 if (data_ready && (request_hci_connection == NULL)){ 840 request_hci_connection = connection; 841 } 842 } else { 843 request_hci_connection = connection; 844 break; 845 } 846 } 847 } 848 849 // stop skipping (handles disconnect by last send connection) 850 skip_connections_until = HCI_CON_HANDLE_INVALID; 851 852 // Exit loop, if we cannot send 853 if (!can_send_now) break; 854 855 // Exit loop, if we can send but there are also no further request 856 if (request_hci_connection == NULL) break; 857 858 // Finally, if we still can send and there are requests, just try again 859 request_hci_connection = NULL; 860 } 861 // update last send con handle for round robin 862 if (last_send_con_handle != HCI_CON_HANDLE_INVALID){ 863 att_server_last_can_send_now = last_send_con_handle; 864 } 865 } 866 867 if (request_hci_connection == NULL) return; 868 869 att_server_t * att_server = &request_hci_connection->att_server; 870 att_connection_t * att_connection = &request_hci_connection->att_connection; 871 att_server_request_can_send_now(att_server, att_connection); 872 } 873 874 static void att_server_handle_att_pdu(att_server_t * att_server, att_connection_t * att_connection, uint8_t * packet, uint16_t size){ 875 876 uint8_t opcode = packet[0u]; 877 uint8_t method = opcode & 0x03fu; 878 bool invalid = method > ATT_MULTIPLE_HANDLE_VALUE_NTF; 879 bool command = (opcode & 0x40u) != 0u; 880 881 // ignore invalid commands 882 if (invalid && command){ 883 return; 884 } 885 886 // handle value indication confirms 887 if ((opcode == ATT_HANDLE_VALUE_CONFIRMATION) && (att_server->value_indication_handle != 0u)){ 888 btstack_run_loop_remove_timer(&att_server->value_indication_timer); 889 uint16_t att_handle = att_server->value_indication_handle; 890 att_server->value_indication_handle = 0u; 891 att_handle_value_indication_notify_client(0u, att_connection->con_handle, att_handle); 892 att_server_request_can_send_now(att_server, att_connection); 893 return; 894 } 895 896 // directly process command 897 // note: signed write cannot be handled directly as authentication needs to be verified 898 if (opcode == ATT_WRITE_COMMAND){ 899 att_handle_request(att_connection, packet, size, NULL); 900 return; 901 } 902 903 // check size 904 if (size > sizeof(att_server->request_buffer)) { 905 log_info("drop att pdu 0x%02x as size %u > att_server->request_buffer %u", packet[0], size, (int) sizeof(att_server->request_buffer)); 906 return; 907 } 908 909 #ifdef ENABLE_LE_SIGNED_WRITE 910 // abort signed write validation if a new request comes in (but finish previous signed write if possible) 911 if (att_server->state == ATT_SERVER_W4_SIGNED_WRITE_VALIDATION){ 912 if (packet[0] == ATT_SIGNED_WRITE_COMMAND){ 913 log_info("skip new signed write request as previous is in validation"); 914 return; 915 } else { 916 log_info("abort signed write validation to process new request"); 917 att_server->state = ATT_SERVER_IDLE; 918 } 919 } 920 #endif 921 // last request still in processing? 922 if (att_server->state != ATT_SERVER_IDLE){ 923 log_info("skip att pdu 0x%02x as server not idle (state %u)", packet[0], att_server->state); 924 return; 925 } 926 927 // store request 928 att_server->state = ATT_SERVER_REQUEST_RECEIVED; 929 att_server->request_size = size; 930 (void)memcpy(att_server->request_buffer, packet, size); 931 932 att_run_for_context(att_server, att_connection); 933 } 934 935 static void att_server_dispatch_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 936 hci_connection_t * hci_connection; 937 att_connection_t * att_connection; 938 att_server_t * att_server; 939 #ifdef ENABLE_GATT_OVER_CLASSIC 940 hci_con_handle_t con_handle; 941 bd_addr_t address; 942 btstack_linked_list_iterator_t it; 943 #endif 944 945 switch (packet_type){ 946 case HCI_EVENT_PACKET: 947 switch (packet[0]){ 948 #ifdef ENABLE_GATT_OVER_CLASSIC 949 case L2CAP_EVENT_CHANNEL_OPENED: 950 con_handle = l2cap_event_channel_opened_get_handle(packet); 951 hci_connection = hci_connection_for_handle(con_handle); 952 if (!hci_connection) break; 953 att_server = &hci_connection->att_server; 954 // store connection info 955 att_server->bearer_type = ATT_BEARER_UNENHANCED_CLASSIC; 956 att_server->peer_addr_type = BD_ADDR_TYPE_ACL; 957 l2cap_event_channel_opened_get_address(packet, att_server->peer_address); 958 att_connection = &hci_connection->att_connection; 959 att_connection->con_handle = con_handle; 960 // reset connection properties 961 att_server->state = ATT_SERVER_IDLE; 962 att_connection->mtu = l2cap_event_channel_opened_get_remote_mtu(packet); 963 att_connection->max_mtu = l2cap_max_mtu(); 964 if (att_connection->max_mtu > ATT_REQUEST_BUFFER_SIZE){ 965 att_connection->max_mtu = ATT_REQUEST_BUFFER_SIZE; 966 } 967 968 log_info("Connection opened %s, l2cap cid %04x, mtu %u", bd_addr_to_str(address), att_server->l2cap_cid, att_connection->mtu); 969 970 // update security params 971 att_connection->encryption_key_size = gap_encryption_key_size(con_handle); 972 att_connection->authenticated = gap_authenticated(con_handle); 973 att_connection->secure_connection = gap_secure_connection(con_handle); 974 log_info("encrypted key size %u, authenticated %u, secure connection %u", 975 att_connection->encryption_key_size, att_connection->authenticated, att_connection->secure_connection); 976 977 // notify connection opened 978 att_emit_connected_event(att_server, att_connection); 979 980 // restore persisten ccc if encrypted 981 if ( gap_security_level(con_handle) >= LEVEL_2){ 982 att_server_persistent_ccc_restore(att_server, att_connection); 983 } 984 // TODO: what to do about le device db? 985 att_server->pairing_active = 0; 986 break; 987 #endif 988 case L2CAP_EVENT_CAN_SEND_NOW: 989 att_server_handle_can_send_now(); 990 break; 991 case ATT_EVENT_MTU_EXCHANGE_COMPLETE: 992 // GATT client has negotiated the mtu for this connection 993 hci_connection = hci_connection_for_handle(channel); 994 if (!hci_connection) break; 995 att_connection = &hci_connection->att_connection; 996 att_connection->mtu = little_endian_read_16(packet, 4); 997 break; 998 default: 999 break; 1000 } 1001 break; 1002 1003 case ATT_DATA_PACKET: 1004 log_debug("ATT Packet, handle 0x%04x", channel); 1005 hci_connection = hci_connection_for_handle(channel); 1006 if (!hci_connection) break; 1007 1008 att_server = &hci_connection->att_server; 1009 att_connection = &hci_connection->att_connection; 1010 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1011 break; 1012 1013 #ifdef ENABLE_GATT_OVER_CLASSIC 1014 case L2CAP_DATA_PACKET: 1015 hci_connections_get_iterator(&it); 1016 while(btstack_linked_list_iterator_has_next(&it)){ 1017 hci_connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 1018 att_server = &hci_connection->att_server; 1019 att_connection = &hci_connection->att_connection; 1020 if (att_server->l2cap_cid == channel) { 1021 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1022 break; 1023 } 1024 } 1025 break; 1026 #endif 1027 1028 default: 1029 break; 1030 } 1031 } 1032 1033 // --------------------- 1034 // persistent CCC writes 1035 static uint32_t att_server_persistent_ccc_tag_for_index(uint8_t index){ 1036 return ('B' << 24u) | ('T' << 16u) | ('C' << 8u) | index; 1037 } 1038 1039 static void att_server_persistent_ccc_write(hci_con_handle_t con_handle, uint16_t att_handle, uint16_t value){ 1040 // lookup att_server instance 1041 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1042 if (!hci_connection) return; 1043 att_server_t * att_server = &hci_connection->att_server; 1044 int le_device_index = att_server->ir_le_device_db_index; 1045 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); 1046 1047 // check if bonded 1048 if (le_device_index < 0) return; 1049 1050 // get btstack_tlv 1051 const btstack_tlv_t * tlv_impl = NULL; 1052 void * tlv_context; 1053 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1054 if (!tlv_impl) return; 1055 1056 // update ccc tag 1057 int index; 1058 uint32_t highest_seq_nr = 0; 1059 uint32_t lowest_seq_nr = 0; 1060 uint32_t tag_for_lowest_seq_nr = 0; 1061 uint32_t tag_for_empty = 0; 1062 persistent_ccc_entry_t entry; 1063 for (index=0; index<NVN_NUM_GATT_SERVER_CCC; index++){ 1064 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1065 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1066 1067 // empty/invalid tag 1068 if (len != sizeof(persistent_ccc_entry_t)){ 1069 tag_for_empty = tag; 1070 continue; 1071 } 1072 // update highest seq nr 1073 if (entry.seq_nr > highest_seq_nr){ 1074 highest_seq_nr = entry.seq_nr; 1075 } 1076 // find entry with lowest seq nr 1077 if ((tag_for_lowest_seq_nr == 0u) || (entry.seq_nr < lowest_seq_nr)){ 1078 tag_for_lowest_seq_nr = tag; 1079 lowest_seq_nr = entry.seq_nr; 1080 } 1081 1082 if (entry.device_index != le_device_index) continue; 1083 if (entry.att_handle != att_handle) continue; 1084 1085 // found matching entry 1086 if (value != 0){ 1087 // update 1088 if (entry.value == value) { 1089 log_info("CCC Index %u: Up-to-date", index); 1090 return; 1091 } 1092 entry.value = (uint8_t) value; 1093 entry.seq_nr = highest_seq_nr + 1u; 1094 log_info("CCC Index %u: Store", index); 1095 int result = tlv_impl->store_tag(tlv_context, tag, (const uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1096 if (result != 0){ 1097 log_error("Store tag index %u failed", index); 1098 } 1099 } else { 1100 // delete 1101 log_info("CCC Index %u: Delete", index); 1102 tlv_impl->delete_tag(tlv_context, tag); 1103 } 1104 return; 1105 } 1106 1107 log_info("tag_for_empty %"PRIx32", tag_for_lowest_seq_nr %"PRIx32, tag_for_empty, tag_for_lowest_seq_nr); 1108 1109 if (value == 0u){ 1110 // done 1111 return; 1112 } 1113 1114 uint32_t tag_to_use = 0u; 1115 if (tag_for_empty != 0u){ 1116 tag_to_use = tag_for_empty; 1117 } else if (tag_for_lowest_seq_nr != 0){ 1118 tag_to_use = tag_for_lowest_seq_nr; 1119 } else { 1120 // should not happen 1121 return; 1122 } 1123 // store ccc tag 1124 entry.seq_nr = highest_seq_nr + 1u; 1125 entry.device_index = le_device_index; 1126 entry.att_handle = att_handle; 1127 entry.value = (uint8_t) value; 1128 int result = tlv_impl->store_tag(tlv_context, tag_to_use, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1129 if (result != 0){ 1130 log_error("Store tag index %u failed", index); 1131 } 1132 } 1133 1134 static void att_server_persistent_ccc_clear(att_server_t * att_server){ 1135 int le_device_index = att_server->ir_le_device_db_index; 1136 log_info("Clear CCC values of remote %s, le device id %d", bd_addr_to_str(att_server->peer_address), le_device_index); 1137 // check if bonded 1138 if (le_device_index < 0) return; 1139 // get btstack_tlv 1140 const btstack_tlv_t * tlv_impl = NULL; 1141 void * tlv_context; 1142 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1143 if (!tlv_impl) return; 1144 // get all ccc tag 1145 int index; 1146 persistent_ccc_entry_t entry; 1147 for (index=0;index<NVN_NUM_GATT_SERVER_CCC;index++){ 1148 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1149 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1150 if (len != sizeof(persistent_ccc_entry_t)) continue; 1151 if (entry.device_index != le_device_index) continue; 1152 // delete entry 1153 log_info("CCC Index %u: Delete", index); 1154 tlv_impl->delete_tag(tlv_context, tag); 1155 } 1156 } 1157 1158 static void att_server_persistent_ccc_restore(att_server_t * att_server, att_connection_t * att_connection){ 1159 int le_device_index = att_server->ir_le_device_db_index; 1160 log_info("Restore CCC values of remote %s, le device id %d", bd_addr_to_str(att_server->peer_address), le_device_index); 1161 // check if bonded 1162 if (le_device_index < 0) return; 1163 // get btstack_tlv 1164 const btstack_tlv_t * tlv_impl = NULL; 1165 void * tlv_context; 1166 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1167 if (!tlv_impl) return; 1168 // get all ccc tag 1169 int index; 1170 persistent_ccc_entry_t entry; 1171 for (index=0;index<NVN_NUM_GATT_SERVER_CCC;index++){ 1172 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1173 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1174 if (len != sizeof(persistent_ccc_entry_t)) continue; 1175 if (entry.device_index != le_device_index) continue; 1176 // simulate write callback 1177 uint16_t attribute_handle = entry.att_handle; 1178 uint8_t value[2]; 1179 little_endian_store_16(value, 0, entry.value); 1180 att_write_callback_t callback = att_server_write_callback_for_handle(attribute_handle); 1181 if (!callback) continue; 1182 log_info("CCC Index %u: Set Attribute handle 0x%04x to value 0x%04x", index, attribute_handle, entry.value ); 1183 (*callback)(att_connection->con_handle, attribute_handle, ATT_TRANSACTION_MODE_NONE, 0, value, sizeof(value)); 1184 } 1185 } 1186 1187 // persistent CCC writes 1188 // --------------------- 1189 1190 // gatt service management 1191 static att_service_handler_t * att_service_handler_for_handle(uint16_t handle){ 1192 btstack_linked_list_iterator_t it; 1193 btstack_linked_list_iterator_init(&it, &service_handlers); 1194 while (btstack_linked_list_iterator_has_next(&it)){ 1195 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1196 if (handler->start_handle > handle) continue; 1197 if (handler->end_handle < handle) continue; 1198 return handler; 1199 } 1200 return NULL; 1201 } 1202 1203 static att_write_callback_t att_server_write_callback_for_handle(uint16_t handle){ 1204 att_service_handler_t * handler = att_service_handler_for_handle(handle); 1205 if (handler != NULL) return handler->write_callback; 1206 return att_server_client_write_callback; 1207 } 1208 1209 static btstack_packet_handler_t att_server_packet_handler_for_handle(uint16_t handle){ 1210 att_service_handler_t * handler = att_service_handler_for_handle(handle); 1211 if (handler != NULL) return handler->packet_handler; 1212 return att_client_packet_handler; 1213 } 1214 1215 static void att_notify_write_callbacks(hci_con_handle_t con_handle, uint16_t transaction_mode){ 1216 // notify all callbacks 1217 btstack_linked_list_iterator_t it; 1218 btstack_linked_list_iterator_init(&it, &service_handlers); 1219 while (btstack_linked_list_iterator_has_next(&it)){ 1220 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1221 if (!handler->write_callback) continue; 1222 (*handler->write_callback)(con_handle, 0, transaction_mode, 0, NULL, 0); 1223 } 1224 if (!att_server_client_write_callback) return; 1225 (*att_server_client_write_callback)(con_handle, 0, transaction_mode, 0, NULL, 0); 1226 } 1227 1228 // returns first reported error or 0 1229 static uint8_t att_validate_prepared_write(hci_con_handle_t con_handle){ 1230 btstack_linked_list_iterator_t it; 1231 btstack_linked_list_iterator_init(&it, &service_handlers); 1232 while (btstack_linked_list_iterator_has_next(&it)){ 1233 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1234 if (!handler->write_callback) continue; 1235 uint8_t error_code = (*handler->write_callback)(con_handle, 0, ATT_TRANSACTION_MODE_VALIDATE, 0, NULL, 0); 1236 if (error_code != 0u) return error_code; 1237 } 1238 if (!att_server_client_write_callback) return 0; 1239 return (*att_server_client_write_callback)(con_handle, 0, ATT_TRANSACTION_MODE_VALIDATE, 0, NULL, 0); 1240 } 1241 1242 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){ 1243 att_service_handler_t * service = att_service_handler_for_handle(attribute_handle); 1244 att_read_callback_t read_callback = (service != NULL) ? service->read_callback : att_server_client_read_callback; 1245 uint16_t result = 0; 1246 if (read_callback != NULL){ 1247 result = (*read_callback)(con_handle, attribute_handle, offset, buffer, buffer_size); 1248 #ifdef ENABLE_ATT_DELAYED_RESPONSE 1249 if (result == ATT_READ_RESPONSE_PENDING){ 1250 if (service == NULL){ 1251 att_server_flags |= ATT_SERVICE_FLAGS_DELAYED_RESPONSE; 1252 } else { 1253 service->flags |= ATT_SERVICE_FLAGS_DELAYED_RESPONSE; 1254 } 1255 } 1256 #endif 1257 } 1258 return result; 1259 } 1260 1261 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){ 1262 switch (transaction_mode){ 1263 case ATT_TRANSACTION_MODE_VALIDATE: 1264 return att_validate_prepared_write(con_handle); 1265 case ATT_TRANSACTION_MODE_EXECUTE: 1266 case ATT_TRANSACTION_MODE_CANCEL: 1267 att_notify_write_callbacks(con_handle, transaction_mode); 1268 return 0; 1269 default: 1270 break; 1271 } 1272 1273 // track CCC writes 1274 if (att_is_persistent_ccc(attribute_handle) && (offset == 0u) && (buffer_size == 2u)){ 1275 att_server_persistent_ccc_write(con_handle, attribute_handle, little_endian_read_16(buffer, 0)); 1276 } 1277 1278 att_write_callback_t callback = att_server_write_callback_for_handle(attribute_handle); 1279 if (!callback) return 0; 1280 return (*callback)(con_handle, attribute_handle, transaction_mode, offset, buffer, buffer_size); 1281 } 1282 1283 /** 1284 * @brief register read/write callbacks for specific handle range 1285 * @param att_service_handler_t 1286 */ 1287 void att_server_register_service_handler(att_service_handler_t * handler){ 1288 bool att_server_registered = false; 1289 if (att_service_handler_for_handle(handler->start_handle) != NULL){ 1290 att_server_registered = true; 1291 } 1292 1293 if (att_service_handler_for_handle(handler->end_handle) != NULL){ 1294 att_server_registered = true; 1295 } 1296 1297 if (att_server_registered){ 1298 log_error("handler for range 0x%04x-0x%04x already registered", handler->start_handle, handler->end_handle); 1299 return; 1300 } 1301 1302 handler->flags = 0; 1303 btstack_linked_list_add(&service_handlers, (btstack_linked_item_t*) handler); 1304 } 1305 1306 void att_server_init(uint8_t const * db, att_read_callback_t read_callback, att_write_callback_t write_callback){ 1307 1308 // store callbacks 1309 att_server_client_read_callback = read_callback; 1310 att_server_client_write_callback = write_callback; 1311 1312 // register for HCI Events 1313 hci_event_callback_registration.callback = &att_server_event_packet_handler; 1314 hci_add_event_handler(&hci_event_callback_registration); 1315 1316 // register for SM events 1317 sm_event_callback_registration.callback = &att_server_event_packet_handler; 1318 sm_add_event_handler(&sm_event_callback_registration); 1319 1320 // and L2CAP ATT Server PDUs 1321 att_dispatch_register_server(att_server_dispatch_packet_handler); 1322 1323 #ifdef ENABLE_GATT_OVER_CLASSIC 1324 // setup l2cap service 1325 att_dispatch_classic_register_service(); 1326 #endif 1327 1328 att_set_db(db); 1329 att_set_read_callback(att_server_read_callback); 1330 att_set_write_callback(att_server_write_callback); 1331 } 1332 1333 void att_server_register_packet_handler(btstack_packet_handler_t handler){ 1334 att_client_packet_handler = handler; 1335 } 1336 1337 1338 // to be deprecated 1339 int att_server_can_send_packet_now(hci_con_handle_t con_handle){ 1340 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1341 if (!hci_connection) return 0; 1342 att_server_t * att_server = &hci_connection->att_server; 1343 att_connection_t * att_connection = &hci_connection->att_connection; 1344 return att_server_can_send_packet(att_server, att_connection); 1345 } 1346 1347 uint8_t att_server_register_can_send_now_callback(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1348 return att_server_request_to_send_notification(callback_registration, con_handle); 1349 } 1350 1351 void att_server_request_can_send_now_event(hci_con_handle_t con_handle){ 1352 att_client_waiting_for_can_send_registration.callback = &att_emit_can_send_now_event; 1353 att_server_request_to_send_notification(&att_client_waiting_for_can_send_registration, con_handle); 1354 } 1355 // end of deprecated 1356 1357 uint8_t att_server_request_to_send_notification(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1358 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1359 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1360 att_server_t * att_server = &hci_connection->att_server; 1361 att_connection_t * att_connection = &hci_connection->att_connection; 1362 bool added = btstack_linked_list_add_tail(&att_server->notification_requests, (btstack_linked_item_t*) callback_registration); 1363 att_server_request_can_send_now(att_server, att_connection); 1364 if (added){ 1365 return ERROR_CODE_SUCCESS; 1366 } else { 1367 return ERROR_CODE_COMMAND_DISALLOWED; 1368 } 1369 } 1370 1371 uint8_t att_server_request_to_send_indication(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1372 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1373 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1374 att_server_t * att_server = &hci_connection->att_server; 1375 att_connection_t * att_connection = &hci_connection->att_connection; 1376 bool added = btstack_linked_list_add_tail(&att_server->indication_requests, (btstack_linked_item_t*) callback_registration); 1377 att_server_request_can_send_now(att_server, att_connection); 1378 if (added){ 1379 return ERROR_CODE_SUCCESS; 1380 } else { 1381 return ERROR_CODE_COMMAND_DISALLOWED; 1382 } 1383 } 1384 1385 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){ 1386 1387 att_server_t * att_server = NULL; 1388 att_connection_t * att_connection = NULL; 1389 uint8_t * packet_buffer = NULL; 1390 1391 // prefer enhanced bearer 1392 #ifdef ENABLE_GATT_OVER_EATT 1393 att_server_eatt_bearer_t * eatt_bearer = att_server_eatt_bearer_for_con_handle(con_handle); 1394 if (eatt_bearer != NULL){ 1395 att_server = &eatt_bearer->att_server; 1396 att_connection = &eatt_bearer->att_connection; 1397 packet_buffer = eatt_bearer->send_buffer; 1398 } else 1399 #endif 1400 { 1401 hci_connection_t *hci_connection = hci_connection_for_handle(con_handle); 1402 if (hci_connection != NULL) { 1403 att_server = &hci_connection->att_server; 1404 att_connection = &hci_connection->att_connection; 1405 } 1406 } 1407 1408 if (att_server == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1409 if (!att_server_can_send_packet(att_server, att_connection)) return BTSTACK_ACL_BUFFERS_FULL; 1410 1411 if (packet_buffer == NULL){ 1412 l2cap_reserve_packet_buffer(); 1413 packet_buffer = l2cap_get_outgoing_buffer(); 1414 } 1415 1416 *out_att_connection = att_connection; 1417 *out_att_server = att_server; 1418 *out_packet_buffer = packet_buffer; 1419 return ERROR_CODE_SUCCESS; 1420 } 1421 1422 uint8_t att_server_notify(hci_con_handle_t con_handle, uint16_t attribute_handle, const uint8_t *value, uint16_t value_len){ 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 uint16_t size = att_prepare_handle_value_notification(att_connection, attribute_handle, value, value_len, packet_buffer); 1433 1434 return att_server_send_prepared(att_server, att_connection, NULL, size); 1435 } 1436 1437 /** 1438 * @brief notify client about multiple attribute value changes 1439 * @param con_handle 1440 * @param num_attributes 1441 * @param attribute_handles[] 1442 * @param values_data[] 1443 * @param values_len[] 1444 * @return 0 if ok, error otherwise 1445 */ 1446 uint8_t att_server_multiple_notify(hci_con_handle_t con_handle, uint8_t num_attributes, 1447 const uint16_t * attribute_handles, const uint8_t ** values_data, const uint16_t * values_len){ 1448 1449 att_server_t * att_server = NULL; 1450 att_connection_t * att_connection = NULL; 1451 uint8_t * packet_buffer = NULL; 1452 1453 uint8_t status = att_server_prepare_server_message(con_handle, &att_server, &att_connection, &packet_buffer); 1454 if (status != ERROR_CODE_SUCCESS){ 1455 return status; 1456 } 1457 1458 uint16_t size = att_prepare_handle_value_multiple_notification(att_connection, num_attributes, attribute_handles, values_data, values_len, packet_buffer); 1459 1460 return att_server_send_prepared(att_server, att_connection, packet_buffer, size); 1461 } 1462 1463 uint8_t att_server_indicate(hci_con_handle_t con_handle, uint16_t attribute_handle, const uint8_t *value, uint16_t value_len){ 1464 1465 att_server_t * att_server = NULL; 1466 att_connection_t * att_connection = NULL; 1467 uint8_t * packet_buffer = NULL; 1468 1469 uint8_t status = att_server_prepare_server_message(con_handle, &att_server, &att_connection, &packet_buffer); 1470 if (status != ERROR_CODE_SUCCESS){ 1471 return status; 1472 } 1473 1474 if (att_server->value_indication_handle != 0u) { 1475 // free reserved packet buffer 1476 if (att_server->bearer_type == ATT_BEARER_ENHANCED_LE){ 1477 l2cap_release_packet_buffer(); 1478 } 1479 return ATT_HANDLE_VALUE_INDICATION_IN_PROGRESS; 1480 } 1481 1482 // track indication 1483 att_server->value_indication_handle = attribute_handle; 1484 btstack_run_loop_set_timer_handler(&att_server->value_indication_timer, att_handle_value_indication_timeout); 1485 btstack_run_loop_set_timer(&att_server->value_indication_timer, ATT_TRANSACTION_TIMEOUT_MS); 1486 btstack_run_loop_add_timer(&att_server->value_indication_timer); 1487 1488 uint16_t size = att_prepare_handle_value_indication(att_connection, attribute_handle, value, value_len, packet_buffer); 1489 1490 return att_server_send_prepared(att_server, att_connection, NULL, size); 1491 } 1492 1493 uint16_t att_server_get_mtu(hci_con_handle_t con_handle){ 1494 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1495 if (!hci_connection) return 0; 1496 att_connection_t * att_connection = &hci_connection->att_connection; 1497 return att_connection->mtu; 1498 } 1499 1500 void att_server_deinit(void){ 1501 att_server_client_read_callback = NULL; 1502 att_server_client_write_callback = NULL; 1503 att_client_packet_handler = NULL; 1504 service_handlers = NULL; 1505 att_server_flags = 0; 1506 } 1507 1508 #ifdef ENABLE_GATT_OVER_EATT 1509 1510 #define MAX_NR_EATT_CHANNELS 5 1511 1512 static uint16_t att_server_eatt_receive_buffer_size; 1513 static uint16_t att_server_eatt_send_buffer_size; 1514 1515 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_cid(uint16_t cid){ 1516 btstack_linked_list_iterator_t it; 1517 btstack_linked_list_iterator_init(&it, &att_server_eatt_bearer_active); 1518 while(btstack_linked_list_iterator_has_next(&it)){ 1519 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) btstack_linked_list_iterator_next(&it); 1520 if (eatt_bearer->att_server.l2cap_cid == cid) { 1521 return eatt_bearer; 1522 } 1523 } 1524 return NULL; 1525 } 1526 1527 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_con_handle(hci_con_handle_t con_handle){ 1528 btstack_linked_list_iterator_t it; 1529 btstack_linked_list_iterator_init(&it, &att_server_eatt_bearer_active); 1530 while(btstack_linked_list_iterator_has_next(&it)){ 1531 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) btstack_linked_list_iterator_next(&it); 1532 if (eatt_bearer->att_connection.con_handle == con_handle) { 1533 return eatt_bearer; 1534 } 1535 } 1536 return NULL; 1537 } 1538 1539 static void att_server_eatt_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 1540 uint16_t cid; 1541 uint8_t status; 1542 uint16_t remote_mtu; 1543 1544 uint8_t i; 1545 uint8_t num_requested_bearers; 1546 uint8_t num_accepted_bearers; 1547 uint16_t initial_credits = L2CAP_LE_AUTOMATIC_CREDITS; 1548 uint8_t * receive_buffers[MAX_NR_EATT_CHANNELS]; 1549 uint16_t cids[MAX_NR_EATT_CHANNELS]; 1550 att_server_eatt_bearer_t * eatt_bearers[MAX_NR_EATT_CHANNELS]; 1551 att_server_eatt_bearer_t * eatt_bearer; 1552 att_server_t * att_server; 1553 att_connection_t * att_connection; 1554 hci_con_handle_t con_handle; 1555 hci_connection_t * hci_connection; 1556 1557 switch (packet_type) { 1558 1559 case L2CAP_DATA_PACKET: 1560 eatt_bearer = att_server_eatt_bearer_for_cid(channel); 1561 btstack_assert(eatt_bearer != NULL); 1562 att_server = &eatt_bearer->att_server; 1563 att_connection = &eatt_bearer->att_connection; 1564 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1565 break; 1566 1567 case HCI_EVENT_PACKET: 1568 switch (packet[0]) { 1569 1570 case L2CAP_EVENT_CAN_SEND_NOW: 1571 cid = l2cap_event_packet_sent_get_local_cid(packet); 1572 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1573 btstack_assert(eatt_bearer != NULL); 1574 att_server = &eatt_bearer->att_server; 1575 att_connection = &eatt_bearer->att_connection; 1576 // only used for EATT request responses 1577 btstack_assert(att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED); 1578 att_server_process_validated_request(att_server, att_connection, eatt_bearer->send_buffer); 1579 break; 1580 1581 case L2CAP_EVENT_PACKET_SENT: 1582 cid = l2cap_event_packet_sent_get_local_cid(packet); 1583 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1584 btstack_assert(eatt_bearer != NULL); 1585 att_server = &eatt_bearer->att_server; 1586 att_connection = &eatt_bearer->att_connection; 1587 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1588 break; 1589 1590 case L2CAP_EVENT_ECBM_INCOMING_CONNECTION: 1591 cid = l2cap_event_ecbm_incoming_connection_get_local_cid(packet); 1592 1593 // reject if outgoing l2cap connection active, L2CAP/TIM/BV-01-C 1594 con_handle = l2cap_event_ecbm_incoming_connection_get_handle(packet); 1595 hci_connection = hci_connection_for_handle(con_handle); 1596 btstack_assert(hci_connection != NULL); 1597 if (hci_connection->att_server.eatt_outgoing_active) { 1598 hci_connection->att_server.incoming_connection_request = true; 1599 l2cap_ecbm_decline_channels(cid, L2CAP_ECBM_CONNECTION_RESULT_SOME_REFUSED_INSUFFICIENT_RESOURCES_AVAILABLE ); 1600 log_info("Decline incoming connection from %s", bd_addr_to_str(hci_connection->address)); 1601 } else { 1602 num_requested_bearers = l2cap_event_ecbm_incoming_connection_get_num_channels(packet); 1603 for (i = 0; i < num_requested_bearers; i++){ 1604 eatt_bearers[i] = (att_server_eatt_bearer_t *) btstack_linked_list_pop(&att_server_eatt_bearer_pool); 1605 if (eatt_bearers[i] == NULL) { 1606 break; 1607 } 1608 eatt_bearers[i]->att_connection.con_handle = l2cap_event_ecbm_incoming_connection_get_handle(packet); 1609 eatt_bearers[i]->att_server.bearer_type = ATT_BEARER_ENHANCED_LE; 1610 receive_buffers[i] = eatt_bearers[i]->receive_buffer; 1611 btstack_linked_list_add(&att_server_eatt_bearer_active, (btstack_linked_item_t *) eatt_bearers[i]); 1612 } 1613 num_accepted_bearers = i; 1614 status = l2cap_ecbm_accept_channels(cid, num_accepted_bearers, initial_credits, att_server_eatt_receive_buffer_size, receive_buffers, cids); 1615 btstack_assert(status == ERROR_CODE_SUCCESS); 1616 log_info("requested %u, accepted %u", num_requested_bearers, num_accepted_bearers); 1617 for (i=0;i<num_accepted_bearers;i++){ 1618 log_info("eatt l2cap cid: 0x%04x", cids[i]); 1619 eatt_bearers[i]->att_server.l2cap_cid = cids[i]; 1620 } 1621 } 1622 break; 1623 1624 case L2CAP_EVENT_ECBM_CHANNEL_OPENED: 1625 cid = l2cap_event_ecbm_channel_opened_get_local_cid(packet); 1626 status = l2cap_event_ecbm_channel_opened_get_status(packet); 1627 remote_mtu = l2cap_event_ecbm_channel_opened_get_remote_mtu(packet); 1628 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1629 btstack_assert(eatt_bearer != NULL); 1630 eatt_bearer->att_connection.mtu_exchanged = true; 1631 eatt_bearer->att_connection.mtu = remote_mtu; 1632 eatt_bearer->att_connection.max_mtu = remote_mtu; 1633 log_info("L2CAP_EVENT_ECBM_CHANNEL_OPENED - cid 0x%04x mtu %u, status 0x%02x", cid, remote_mtu, status); 1634 break; 1635 1636 case L2CAP_EVENT_ECBM_RECONFIGURED: 1637 break; 1638 1639 case L2CAP_EVENT_CHANNEL_CLOSED: 1640 eatt_bearer = att_server_eatt_bearer_for_cid(l2cap_event_channel_closed_get_local_cid(packet)); 1641 btstack_assert(eatt_bearers != NULL); 1642 1643 // TODO: finalize - abort queued writes 1644 1645 btstack_linked_list_remove(&att_server_eatt_bearer_active, (btstack_linked_item_t *) eatt_bearer); 1646 btstack_linked_list_add(&att_server_eatt_bearer_pool, (btstack_linked_item_t *) eatt_bearer); 1647 break; 1648 default: 1649 break; 1650 } 1651 break; 1652 default: 1653 btstack_unreachable(); 1654 break; 1655 } 1656 } 1657 1658 // create eatt bearers 1659 uint8_t att_server_eatt_init(uint8_t num_eatt_bearers, uint8_t * storage_buffer, uint16_t storage_size){ 1660 uint16_t size_for_structs = num_eatt_bearers * sizeof(att_server_eatt_bearer_t); 1661 if (storage_size < size_for_structs) { 1662 return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED; 1663 } 1664 1665 // TODO: The minimum ATT_MTU for an Enhanced ATT bearer is 64 octets. 1666 1667 memset(storage_buffer, 0, storage_size); 1668 uint16_t buffer_size_per_bearer = ((storage_size - size_for_structs) / num_eatt_bearers); 1669 att_server_eatt_receive_buffer_size = buffer_size_per_bearer / 2; 1670 att_server_eatt_send_buffer_size = buffer_size_per_bearer / 2; 1671 uint8_t * bearer_buffer = &storage_buffer[size_for_structs]; 1672 uint8_t i; 1673 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) storage_buffer; 1674 log_info("%u EATT bearers with receive buffer size %u", 1675 num_eatt_bearers, att_server_eatt_receive_buffer_size); 1676 for (i=0;i<num_eatt_bearers;i++){ 1677 eatt_bearer->att_connection.con_handle = HCI_CON_HANDLE_INVALID; 1678 eatt_bearer->receive_buffer = bearer_buffer; 1679 bearer_buffer += att_server_eatt_receive_buffer_size; 1680 eatt_bearer->send_buffer = bearer_buffer; 1681 bearer_buffer += att_server_eatt_send_buffer_size; 1682 btstack_linked_list_add(&att_server_eatt_bearer_pool, (btstack_linked_item_t *) eatt_bearer); 1683 eatt_bearer++; 1684 } 1685 // TODO: define minimum EATT MTU 1686 l2cap_ecbm_register_service(att_server_eatt_handler, BLUETOOTH_PSM_EATT, 64, 0, false); 1687 1688 return 0; 1689 } 1690 #endif 1691