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 "bluetooth_psm.h" 58 #include "btstack_debug.h" 59 #include "btstack_event.h" 60 #include "btstack_memory.h" 61 #include "btstack_run_loop.h" 62 #include "gap.h" 63 #include "hci.h" 64 #include "hci_dump.h" 65 #include "l2cap.h" 66 #include "btstack_tlv.h" 67 #ifdef ENABLE_LE_SIGNED_WRITE 68 #include "ble/sm.h" 69 #include "bluetooth_psm.h" 70 71 #endif 72 73 #ifdef ENABLE_TESTING_SUPPORT 74 #include <stdio.h> 75 #endif 76 77 #ifndef NVN_NUM_GATT_SERVER_CCC 78 #define NVN_NUM_GATT_SERVER_CCC 20 79 #endif 80 81 #define ATT_SERVICE_FLAGS_DELAYED_RESPONSE (1<<0u) 82 83 static void att_run_for_context(att_server_t * att_server, att_connection_t * att_connection); 84 static att_write_callback_t att_server_write_callback_for_handle(uint16_t handle); 85 static btstack_packet_handler_t att_server_packet_handler_for_handle(uint16_t handle); 86 static void att_server_handle_can_send_now(void); 87 static void att_server_persistent_ccc_restore(att_server_t * att_server, att_connection_t * att_connection); 88 static void att_server_persistent_ccc_clear(att_server_t * att_server); 89 static void att_server_handle_att_pdu(att_server_t * att_server, att_connection_t * att_connection, uint8_t * packet, uint16_t size); 90 91 typedef enum { 92 ATT_SERVER_RUN_PHASE_1_REQUESTS = 0, 93 ATT_SERVER_RUN_PHASE_2_INDICATIONS, 94 ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS, 95 } att_server_run_phase_t; 96 97 // 98 typedef struct { 99 uint32_t seq_nr; 100 uint16_t att_handle; 101 uint8_t value; 102 uint8_t device_index; 103 } persistent_ccc_entry_t; 104 105 // global 106 static btstack_packet_callback_registration_t hci_event_callback_registration; 107 static btstack_packet_callback_registration_t sm_event_callback_registration; 108 static btstack_packet_handler_t att_client_packet_handler; 109 static btstack_linked_list_t service_handlers; 110 static btstack_context_callback_registration_t att_client_waiting_for_can_send_registration; 111 112 static att_read_callback_t att_server_client_read_callback; 113 static att_write_callback_t att_server_client_write_callback; 114 115 // round robin 116 static hci_con_handle_t att_server_last_can_send_now = HCI_CON_HANDLE_INVALID; 117 118 static uint8_t att_server_flags; 119 120 #ifdef ENABLE_GATT_OVER_EATT 121 typedef struct { 122 btstack_linked_item_t item; 123 att_server_t att_server; 124 att_connection_t att_connection; 125 uint8_t * receive_buffer; 126 uint8_t * send_buffer; 127 } att_server_eatt_bearer_t; 128 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_con_handle(hci_con_handle_t con_handle); 129 static btstack_linked_list_t att_server_eatt_bearer_pool; 130 static btstack_linked_list_t att_server_eatt_bearer_active; 131 #endif 132 133 #ifdef ENABLE_LE_SIGNED_WRITE 134 static bool att_server_connections_for_state(att_server_state_t state, att_server_t ** att_server_out, att_connection_t ** att_connection_out){ 135 btstack_linked_list_iterator_t it; 136 hci_connections_get_iterator(&it); 137 while(btstack_linked_list_iterator_has_next(&it)){ 138 hci_connection_t * hci_connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 139 if (hci_connection->att_server.state == state) { 140 *att_server_out = &hci_connection->att_server; 141 *att_connection_out = &hci_connection->att_connection; 142 return true; 143 } 144 } 145 146 #ifdef ENABLE_GATT_OVER_EATT 147 btstack_linked_list_iterator_init(&it, &att_server_eatt_bearer_active); 148 while(btstack_linked_list_iterator_has_next(&it)){ 149 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) btstack_linked_list_iterator_next(&it); 150 if (eatt_bearer->att_server.state == state) { 151 *att_server_out = &eatt_bearer->att_server; 152 *att_connection_out = &eatt_bearer->att_connection; 153 return true; 154 } 155 } 156 #endif 157 158 return false; 159 } 160 #endif 161 162 static void att_server_request_can_send_now(att_server_t * att_server, att_connection_t * att_connection ){ 163 switch (att_server->bearer_type){ 164 case ATT_BEARER_UNENHANCED_LE: 165 #ifdef ENABLE_GATT_OVER_CLASSIC 166 case ATT_BEARER_UNENHANCED_CLASSIC: 167 /* fall through */ 168 #endif 169 att_dispatch_server_request_can_send_now_event(att_connection->con_handle); 170 break; 171 #ifdef ENABLE_GATT_OVER_EATT 172 case ATT_BEARER_ENHANCED_LE: 173 l2cap_request_can_send_now_event(att_server->l2cap_cid); 174 break; 175 #endif 176 default: 177 btstack_unreachable(); 178 break; 179 } 180 } 181 182 static bool att_server_can_send_packet(att_server_t * att_server, att_connection_t * att_connection){ 183 switch (att_server->bearer_type) { 184 case ATT_BEARER_UNENHANCED_LE: 185 #ifdef ENABLE_GATT_OVER_CLASSIC 186 case ATT_BEARER_UNENHANCED_CLASSIC: 187 /* fall through */ 188 #endif 189 return att_dispatch_server_can_send_now(att_connection->con_handle); 190 #ifdef ENABLE_GATT_OVER_EATT 191 case ATT_BEARER_ENHANCED_LE: 192 return l2cap_can_send_packet_now(att_server->l2cap_cid); 193 #endif 194 default: 195 btstack_unreachable(); 196 break; 197 } 198 return false; 199 } 200 201 static void att_handle_value_indication_notify_client(uint8_t status, uint16_t client_handle, uint16_t attribute_handle){ 202 btstack_packet_handler_t packet_handler = att_server_packet_handler_for_handle(attribute_handle); 203 if (!packet_handler) return; 204 205 uint8_t event[7]; 206 int pos = 0; 207 event[pos++] = ATT_EVENT_HANDLE_VALUE_INDICATION_COMPLETE; 208 event[pos++] = sizeof(event) - 2u; 209 event[pos++] = status; 210 little_endian_store_16(event, pos, client_handle); 211 pos += 2; 212 little_endian_store_16(event, pos, attribute_handle); 213 (*packet_handler)(HCI_EVENT_PACKET, 0, &event[0], sizeof(event)); 214 } 215 216 static void att_emit_event_to_all(const uint8_t * event, uint16_t size){ 217 // dispatch to app level handler 218 if (att_client_packet_handler != NULL){ 219 (*att_client_packet_handler)(HCI_EVENT_PACKET, 0, (uint8_t*) event, size); 220 } 221 222 // dispatch to service handlers 223 btstack_linked_list_iterator_t it; 224 btstack_linked_list_iterator_init(&it, &service_handlers); 225 while (btstack_linked_list_iterator_has_next(&it)){ 226 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 227 if (!handler->packet_handler) continue; 228 (*handler->packet_handler)(HCI_EVENT_PACKET, 0, (uint8_t*) event, size); 229 } 230 } 231 232 static void att_emit_mtu_event(hci_con_handle_t con_handle, uint16_t mtu){ 233 uint8_t event[6]; 234 int pos = 0; 235 event[pos++] = ATT_EVENT_MTU_EXCHANGE_COMPLETE; 236 event[pos++] = sizeof(event) - 2u; 237 little_endian_store_16(event, pos, con_handle); 238 pos += 2; 239 little_endian_store_16(event, pos, mtu); 240 241 // also dispatch to GATT Clients 242 att_dispatch_server_mtu_exchanged(con_handle, mtu); 243 244 // dispatch to app level handler and service handlers 245 att_emit_event_to_all(&event[0], sizeof(event)); 246 } 247 248 static void att_emit_can_send_now_event(void * context){ 249 UNUSED(context); 250 if (!att_client_packet_handler) return; 251 252 uint8_t event[] = { ATT_EVENT_CAN_SEND_NOW, 0}; 253 (*att_client_packet_handler)(HCI_EVENT_PACKET, 0, &event[0], sizeof(event)); 254 } 255 256 static void att_emit_connected_event(att_server_t * att_server, att_connection_t * att_connection){ 257 uint8_t event[11]; 258 int pos = 0; 259 event[pos++] = ATT_EVENT_CONNECTED; 260 event[pos++] = sizeof(event) - 2u; 261 event[pos++] = att_server->peer_addr_type; 262 reverse_bd_addr(att_server->peer_address, &event[pos]); 263 pos += 6; 264 little_endian_store_16(event, pos, att_connection->con_handle); 265 pos += 2; 266 267 // dispatch to app level handler and service handlers 268 att_emit_event_to_all(&event[0], sizeof(event)); 269 } 270 271 272 static void att_emit_disconnected_event(uint16_t con_handle){ 273 uint8_t event[4]; 274 int pos = 0; 275 event[pos++] = ATT_EVENT_DISCONNECTED; 276 event[pos++] = sizeof(event) - 2u; 277 little_endian_store_16(event, pos, con_handle); 278 pos += 2; 279 280 // dispatch to app level handler and service handlers 281 att_emit_event_to_all(&event[0], sizeof(event)); 282 } 283 284 static void att_handle_value_indication_timeout(btstack_timer_source_t *ts){ 285 void * context = btstack_run_loop_get_timer_context(ts); 286 hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) context; 287 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 288 if (!hci_connection) return; 289 // @note: after a transaction timeout, no more requests shall be sent over this ATT Bearer 290 // (that's why we don't reset the value_indication_handle) 291 att_server_t * att_server = &hci_connection->att_server; 292 uint16_t att_handle = att_server->value_indication_handle; 293 att_connection_t * att_connection = &hci_connection->att_connection; 294 att_handle_value_indication_notify_client((uint8_t)ATT_HANDLE_VALUE_INDICATION_TIMEOUT, att_connection->con_handle, att_handle); 295 } 296 297 static void att_server_event_packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 298 299 UNUSED(channel); // ok: there is no channel 300 UNUSED(size); // ok: handling own l2cap events 301 302 att_server_t * att_server; 303 att_connection_t * att_connection; 304 hci_con_handle_t con_handle; 305 hci_connection_t * hci_connection; 306 307 switch (packet_type) { 308 309 case HCI_EVENT_PACKET: 310 switch (hci_event_packet_get_type(packet)) { 311 case HCI_EVENT_META_GAP: 312 switch (hci_event_gap_meta_get_subevent_code(packet)) { 313 case GAP_SUBEVENT_LE_CONNECTION_COMPLETE: 314 con_handle = gap_subevent_le_connection_complete_get_connection_handle(packet); 315 hci_connection = hci_connection_for_handle(con_handle); 316 if (!hci_connection) break; 317 att_server = &hci_connection->att_server; 318 // store connection info 319 att_server->peer_addr_type = gap_subevent_le_connection_complete_get_peer_address_type(packet); 320 gap_subevent_le_connection_complete_get_peer_address(packet, att_server->peer_address); 321 att_connection = &hci_connection->att_connection; 322 att_connection->con_handle = con_handle; 323 // reset connection properties 324 att_server->state = ATT_SERVER_IDLE; 325 att_server->bearer_type = ATT_BEARER_UNENHANCED_LE; 326 att_connection->mtu = ATT_DEFAULT_MTU; 327 att_connection->max_mtu = l2cap_max_le_mtu(); 328 if (att_connection->max_mtu > ATT_REQUEST_BUFFER_SIZE){ 329 att_connection->max_mtu = ATT_REQUEST_BUFFER_SIZE; 330 } 331 att_connection->encryption_key_size = 0u; 332 att_connection->authenticated = 0u; 333 att_connection->authorized = 0u; 334 // workaround: identity resolving can already be complete, at least store result 335 att_server->ir_le_device_db_index = sm_le_device_index(con_handle); 336 att_server->ir_lookup_active = false; 337 att_server->pairing_active = false; 338 // notify all - new 339 att_emit_connected_event(att_server, att_connection); 340 break; 341 default: 342 break; 343 } 344 break; 345 346 case HCI_EVENT_LE_META: 347 switch (hci_event_le_meta_get_subevent_code(packet)) { 348 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE: 349 // forward LE Connection Complete event to keep backward compatibility 350 // deprecated: please register hci handler with hci_add_event_handler or handle ATT_EVENT_CONNECTED 351 att_emit_event_to_all(packet, size); 352 break; 353 default: 354 break; 355 } 356 break; 357 358 case HCI_EVENT_ENCRYPTION_CHANGE: 359 case HCI_EVENT_ENCRYPTION_CHANGE_V2: 360 case HCI_EVENT_ENCRYPTION_KEY_REFRESH_COMPLETE: 361 // check handle 362 con_handle = little_endian_read_16(packet, 3); 363 hci_connection = hci_connection_for_handle(con_handle); 364 if (!hci_connection) break; 365 if (gap_get_connection_type(con_handle) != GAP_CONNECTION_LE) break; 366 // update security params 367 att_server = &hci_connection->att_server; 368 att_connection = &hci_connection->att_connection; 369 att_connection->encryption_key_size = gap_encryption_key_size(con_handle); 370 att_connection->authenticated = gap_authenticated(con_handle) ? 1 : 0; 371 att_connection->secure_connection = gap_secure_connection(con_handle) ? 1 : 0; 372 log_info("encrypted key size %u, authenticated %u, secure connection %u", 373 att_connection->encryption_key_size, att_connection->authenticated, att_connection->secure_connection); 374 if (hci_event_packet_get_type(packet) == HCI_EVENT_ENCRYPTION_CHANGE){ 375 // restore CCC values when encrypted for LE Connections 376 if (hci_event_encryption_change_get_encryption_enabled(packet) != 0){ 377 att_server_persistent_ccc_restore(att_server, att_connection); 378 } 379 } 380 att_run_for_context(att_server, att_connection); 381 break; 382 383 case HCI_EVENT_DISCONNECTION_COMPLETE: 384 // check handle 385 con_handle = hci_event_disconnection_complete_get_connection_handle(packet); 386 hci_connection = hci_connection_for_handle(con_handle); 387 if (!hci_connection) break; 388 att_server = &hci_connection->att_server; 389 att_connection = &hci_connection->att_connection; 390 att_clear_transaction_queue(att_connection); 391 att_connection->con_handle = 0; 392 att_server->pairing_active = false; 393 att_server->state = ATT_SERVER_IDLE; 394 if (att_server->value_indication_handle != 0u){ 395 btstack_run_loop_remove_timer(&att_server->value_indication_timer); 396 uint16_t att_handle = att_server->value_indication_handle; 397 att_server->value_indication_handle = 0u; // reset error state 398 att_handle_value_indication_notify_client((uint8_t)ATT_HANDLE_VALUE_INDICATION_DISCONNECT, att_connection->con_handle, att_handle); 399 } 400 // notify all - new 401 att_emit_disconnected_event(con_handle); 402 // notify all - old 403 att_emit_event_to_all(packet, size); 404 break; 405 406 // Identity Resolving 407 case SM_EVENT_IDENTITY_RESOLVING_STARTED: 408 con_handle = sm_event_identity_resolving_started_get_handle(packet); 409 hci_connection = hci_connection_for_handle(con_handle); 410 if (!hci_connection) break; 411 att_server = &hci_connection->att_server; 412 log_info("SM_EVENT_IDENTITY_RESOLVING_STARTED"); 413 att_server->ir_lookup_active = true; 414 break; 415 case SM_EVENT_IDENTITY_RESOLVING_SUCCEEDED: 416 con_handle = sm_event_identity_created_get_handle(packet); 417 hci_connection = hci_connection_for_handle(con_handle); 418 if (!hci_connection) return; 419 att_connection = &hci_connection->att_connection; 420 att_server = &hci_connection->att_server; 421 att_server->ir_lookup_active = false; 422 att_server->ir_le_device_db_index = sm_event_identity_resolving_succeeded_get_index(packet); 423 log_info("SM_EVENT_IDENTITY_RESOLVING_SUCCEEDED"); 424 att_run_for_context(att_server, att_connection); 425 break; 426 case SM_EVENT_IDENTITY_RESOLVING_FAILED: 427 con_handle = sm_event_identity_resolving_failed_get_handle(packet); 428 hci_connection = hci_connection_for_handle(con_handle); 429 if (!hci_connection) break; 430 att_connection = &hci_connection->att_connection; 431 att_server = &hci_connection->att_server; 432 log_info("SM_EVENT_IDENTITY_RESOLVING_FAILED"); 433 att_server->ir_lookup_active = false; 434 att_server->ir_le_device_db_index = -1; 435 att_run_for_context(att_server, att_connection); 436 break; 437 438 // Pairing started - delete stored CCC values 439 // - assumes pairing indicates either new device or re-pairing, in both cases there should be no stored CCC values 440 // - assumes that all events have the con handle as the first field 441 case SM_EVENT_JUST_WORKS_REQUEST: 442 case SM_EVENT_PASSKEY_DISPLAY_NUMBER: 443 case SM_EVENT_PASSKEY_INPUT_NUMBER: 444 case SM_EVENT_NUMERIC_COMPARISON_REQUEST: 445 con_handle = sm_event_just_works_request_get_handle(packet); 446 hci_connection = hci_connection_for_handle(con_handle); 447 if (!hci_connection) break; 448 att_server = &hci_connection->att_server; 449 log_info("SM Pairing started"); 450 att_server->pairing_active = true; 451 if (att_server->ir_le_device_db_index < 0) break; 452 att_server_persistent_ccc_clear(att_server); 453 // index not valid anymore 454 att_server->ir_le_device_db_index = -1; 455 break; 456 457 // Bonding completed 458 case SM_EVENT_IDENTITY_CREATED: 459 con_handle = sm_event_identity_created_get_handle(packet); 460 hci_connection = hci_connection_for_handle(con_handle); 461 if (!hci_connection) return; 462 att_connection = &hci_connection->att_connection; 463 att_server = &hci_connection->att_server; 464 att_server->pairing_active = false; 465 att_server->ir_le_device_db_index = sm_event_identity_created_get_index(packet); 466 att_run_for_context(att_server, att_connection); 467 break; 468 469 // Pairing complete (with/without bonding=storing of pairing information) 470 case SM_EVENT_PAIRING_COMPLETE: 471 con_handle = sm_event_pairing_complete_get_handle(packet); 472 hci_connection = hci_connection_for_handle(con_handle); 473 if (!hci_connection) return; 474 att_connection = &hci_connection->att_connection; 475 att_server = &hci_connection->att_server; 476 att_server->pairing_active = false; 477 att_run_for_context(att_server, att_connection); 478 break; 479 480 // Authorization 481 case SM_EVENT_AUTHORIZATION_RESULT: { 482 con_handle = sm_event_authorization_result_get_handle(packet); 483 hci_connection = hci_connection_for_handle(con_handle); 484 if (!hci_connection) break; 485 att_connection = &hci_connection->att_connection; 486 att_server = &hci_connection->att_server; 487 att_connection->authorized = sm_event_authorization_result_get_authorization_result(packet); 488 att_server_request_can_send_now(att_server, att_connection); 489 break; 490 } 491 default: 492 break; 493 } 494 break; 495 default: 496 break; 497 } 498 } 499 500 static uint8_t 501 att_server_send_prepared(const att_server_t *att_server, const att_connection_t *att_connection, uint8_t *buffer, 502 uint16_t size) { 503 UNUSED(buffer); 504 uint8_t status = ERROR_CODE_SUCCESS; 505 switch (att_server->bearer_type) { 506 case ATT_BEARER_UNENHANCED_LE: 507 status = l2cap_send_prepared_connectionless(att_connection->con_handle, L2CAP_CID_ATTRIBUTE_PROTOCOL, size); 508 break; 509 #ifdef ENABLE_GATT_OVER_CLASSIC 510 case ATT_BEARER_UNENHANCED_CLASSIC: 511 status = l2cap_send_prepared(att_server->l2cap_cid, size); 512 break; 513 #endif 514 #ifdef ENABLE_GATT_OVER_EATT 515 case ATT_BEARER_ENHANCED_LE: 516 btstack_assert(buffer != NULL); 517 status = l2cap_send(att_server->l2cap_cid, buffer, size); 518 break; 519 #endif 520 default: 521 btstack_unreachable(); 522 break; 523 } 524 return status; 525 } 526 527 #ifdef ENABLE_LE_SIGNED_WRITE 528 static void att_signed_write_handle_cmac_result(uint8_t hash[8]){ 529 att_server_t * att_server = NULL; 530 att_connection_t * att_connection = NULL; 531 bool found = att_server_connections_for_state(ATT_SERVER_W4_SIGNED_WRITE_VALIDATION, &att_server, &att_connection); 532 533 if (found == false){ 534 return; 535 } 536 537 uint8_t hash_flipped[8]; 538 reverse_64(hash, hash_flipped); 539 if (memcmp(hash_flipped, &att_server->request_buffer[att_server->request_size-8], 8) != 0){ 540 log_info("ATT Signed Write, invalid signature"); 541 #ifdef ENABLE_TESTING_SUPPORT 542 printf("ATT Signed Write, invalid signature\n"); 543 #endif 544 att_server->state = ATT_SERVER_IDLE; 545 return; 546 } 547 log_info("ATT Signed Write, valid signature"); 548 #ifdef ENABLE_TESTING_SUPPORT 549 printf("ATT Signed Write, valid signature\n"); 550 #endif 551 552 // update sequence number 553 uint32_t counter_packet = little_endian_read_32(att_server->request_buffer, att_server->request_size-12); 554 le_device_db_remote_counter_set(att_server->ir_le_device_db_index, counter_packet+1); 555 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 556 att_server_request_can_send_now(att_server, att_connection); 557 } 558 #endif 559 560 #ifdef ENABLE_ATT_DELAYED_RESPONSE 561 static void att_server_handle_response_pending(att_server_t *att_server, const att_connection_t *att_connection, 562 const uint8_t *eatt_buffer, 563 uint16_t att_response_size) { 564 // update state 565 att_server->state = ATT_SERVER_RESPONSE_PENDING; 566 567 // callback with handle ATT_READ_RESPONSE_PENDING for reads 568 if (att_response_size == ATT_READ_RESPONSE_PENDING){ 569 // notify services that returned response pending 570 btstack_linked_list_iterator_t it; 571 btstack_linked_list_iterator_init(&it, &service_handlers); 572 while (btstack_linked_list_iterator_has_next(&it)) { 573 att_service_handler_t *handler = (att_service_handler_t *) btstack_linked_list_iterator_next(&it); 574 if ((handler->flags & ATT_SERVICE_FLAGS_DELAYED_RESPONSE) != 0){ 575 handler->flags &= ~ATT_SERVICE_FLAGS_DELAYED_RESPONSE; 576 handler->read_callback(att_connection->con_handle, ATT_READ_RESPONSE_PENDING, 0, NULL, 0); 577 } 578 } 579 // notify main read callback if it returned response pending 580 if ((att_server_flags & ATT_SERVICE_FLAGS_DELAYED_RESPONSE) != 0){ 581 // flag was set by read callback 582 btstack_assert(att_server_client_read_callback != NULL); 583 (*att_server_client_read_callback)(att_connection->con_handle, ATT_READ_RESPONSE_PENDING, 0, NULL, 0); 584 } 585 } 586 587 // free reserved buffer - might trigger next read/write 588 if (eatt_buffer == NULL){ 589 l2cap_release_packet_buffer(); 590 } 591 } 592 #endif 593 594 // pre: att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED 595 // pre: can send now 596 // uses l2cap outgoing buffer if no eatt_buffer provided 597 // returns: 1 if packet was sent 598 static int 599 att_server_process_validated_request(att_server_t *att_server, att_connection_t *att_connection, uint8_t *eatt_buffer) { 600 601 uint8_t * att_response_buffer; 602 if (eatt_buffer != NULL){ 603 att_response_buffer = eatt_buffer; 604 } else { 605 l2cap_reserve_packet_buffer(); 606 att_response_buffer = l2cap_get_outgoing_buffer(); 607 } 608 609 uint16_t att_response_size = 0; 610 // Send Error Response for MTU Request over connection-oriented channel 611 if ((att_server->bearer_type != ATT_BEARER_UNENHANCED_LE) && (att_server->request_buffer[0] == ATT_EXCHANGE_MTU_REQUEST)){ 612 att_response_size = 5; 613 att_response_buffer[0] = ATT_ERROR_RESPONSE; 614 att_response_buffer[1] = ATT_EXCHANGE_MTU_REQUEST; 615 att_response_buffer[2] = 0; 616 att_response_buffer[3] = 0; 617 att_response_buffer[4] = ATT_ERROR_REQUEST_NOT_SUPPORTED; 618 } else { 619 att_response_size = att_handle_request(att_connection, att_server->request_buffer, att_server->request_size, att_response_buffer); 620 } 621 622 #ifdef ENABLE_ATT_DELAYED_RESPONSE 623 if ((att_response_size == ATT_READ_RESPONSE_PENDING) || (att_response_size == ATT_INTERNAL_WRITE_RESPONSE_PENDING)){ 624 att_server_handle_response_pending(att_server, att_connection, eatt_buffer, att_response_size); 625 return 0; 626 } 627 #endif 628 629 // intercept "insufficient authorization" for authenticated connections to allow for user authorization 630 if ((att_response_size >= 4u) 631 && (att_response_buffer[0] == ATT_ERROR_RESPONSE) 632 && (att_response_buffer[4] == ATT_ERROR_INSUFFICIENT_AUTHORIZATION) 633 && (att_connection->authenticated != 0u)){ 634 635 switch (gap_authorization_state(att_connection->con_handle)){ 636 case AUTHORIZATION_UNKNOWN: 637 if (eatt_buffer == NULL){ 638 l2cap_release_packet_buffer(); 639 } 640 sm_request_pairing(att_connection->con_handle); 641 return 0; 642 case AUTHORIZATION_PENDING: 643 if (eatt_buffer == NULL){ 644 l2cap_release_packet_buffer(); 645 } 646 return 0; 647 default: 648 break; 649 } 650 } 651 652 att_server->state = ATT_SERVER_IDLE; 653 if (att_response_size == 0u) { 654 if (eatt_buffer == NULL){ 655 l2cap_release_packet_buffer(); 656 } 657 return 0; 658 } 659 660 (void) att_server_send_prepared(att_server, att_connection, eatt_buffer, att_response_size); 661 662 // notify client about MTU exchange result 663 if (att_response_buffer[0] == ATT_EXCHANGE_MTU_RESPONSE){ 664 att_emit_mtu_event(att_connection->con_handle, att_connection->mtu); 665 } 666 return 1; 667 } 668 669 #ifdef ENABLE_ATT_DELAYED_RESPONSE 670 uint8_t att_server_response_ready(hci_con_handle_t con_handle){ 671 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 672 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 673 att_server_t * att_server = &hci_connection->att_server; 674 att_connection_t * att_connection = &hci_connection->att_connection; 675 if (att_server->state != ATT_SERVER_RESPONSE_PENDING) return ERROR_CODE_COMMAND_DISALLOWED; 676 677 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 678 att_server_request_can_send_now(att_server, att_connection); 679 return ERROR_CODE_SUCCESS; 680 } 681 #endif 682 683 static void att_run_for_context(att_server_t * att_server, att_connection_t * att_connection){ 684 switch (att_server->state){ 685 case ATT_SERVER_REQUEST_RECEIVED: 686 switch (att_server->bearer_type){ 687 case ATT_BEARER_UNENHANCED_LE: 688 // wait until re-encryption as central is complete 689 if (gap_reconnect_security_setup_active(att_connection->con_handle)) { 690 return; 691 }; 692 break; 693 #if defined(ENABLE_GATT_OVER_CLASSIC) || defined (ENABLE_GATT_OVER_EATT) 694 #ifdef ENABLE_GATT_OVER_CLASSIC 695 case ATT_BEARER_UNENHANCED_CLASSIC: 696 /* fall through */ 697 #endif 698 #ifdef ENABLE_GATT_OVER_EATT 699 case ATT_BEARER_ENHANCED_LE: 700 #endif 701 // ok 702 break; 703 #endif 704 default: 705 btstack_unreachable(); 706 break; 707 } 708 709 // wait until pairing is complete 710 if (att_server->pairing_active) break; 711 712 #ifdef ENABLE_LE_SIGNED_WRITE 713 if (att_server->request_buffer[0] == ATT_SIGNED_WRITE_COMMAND){ 714 log_info("ATT Signed Write!"); 715 if (!sm_cmac_ready()) { 716 log_info("ATT Signed Write, sm_cmac engine not ready. Abort"); 717 att_server->state = ATT_SERVER_IDLE; 718 return; 719 } 720 if (att_server->request_size < (3 + 12)) { 721 log_info("ATT Signed Write, request to short. Abort."); 722 att_server->state = ATT_SERVER_IDLE; 723 return; 724 } 725 if (att_server->ir_lookup_active){ 726 return; 727 } 728 if (att_server->ir_le_device_db_index < 0){ 729 log_info("ATT Signed Write, CSRK not available"); 730 att_server->state = ATT_SERVER_IDLE; 731 return; 732 } 733 734 // check counter 735 uint32_t counter_packet = little_endian_read_32(att_server->request_buffer, att_server->request_size-12); 736 uint32_t counter_db = le_device_db_remote_counter_get(att_server->ir_le_device_db_index); 737 log_info("ATT Signed Write, DB counter %"PRIu32", packet counter %"PRIu32, counter_db, counter_packet); 738 if (counter_packet < counter_db){ 739 log_info("ATT Signed Write, db reports higher counter, abort"); 740 att_server->state = ATT_SERVER_IDLE; 741 return; 742 } 743 744 // signature is { sequence counter, secure hash } 745 sm_key_t csrk; 746 le_device_db_remote_csrk_get(att_server->ir_le_device_db_index, csrk); 747 att_server->state = ATT_SERVER_W4_SIGNED_WRITE_VALIDATION; 748 log_info("Orig Signature: "); 749 log_info_hexdump( &att_server->request_buffer[att_server->request_size-8], 8); 750 uint16_t attribute_handle = little_endian_read_16(att_server->request_buffer, 1); 751 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); 752 return; 753 } 754 #endif 755 // move on 756 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 757 att_server_request_can_send_now(att_server, att_connection); 758 break; 759 760 default: 761 break; 762 } 763 } 764 765 static bool att_server_data_ready_for_phase(att_server_t * att_server, att_server_run_phase_t phase){ 766 switch (phase){ 767 case ATT_SERVER_RUN_PHASE_1_REQUESTS: 768 return att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 769 case ATT_SERVER_RUN_PHASE_2_INDICATIONS: 770 return (!btstack_linked_list_empty(&att_server->indication_requests) && (att_server->value_indication_handle == 0u)); 771 case ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS: 772 return (!btstack_linked_list_empty(&att_server->notification_requests)); 773 default: 774 btstack_assert(false); 775 return false; 776 } 777 } 778 779 static void att_server_trigger_send_for_phase(att_server_t * att_server, att_connection_t * att_connection, att_server_run_phase_t phase){ 780 btstack_context_callback_registration_t * client; 781 switch (phase){ 782 case ATT_SERVER_RUN_PHASE_1_REQUESTS: 783 att_server_process_validated_request(att_server, att_connection, NULL); 784 break; 785 case ATT_SERVER_RUN_PHASE_2_INDICATIONS: 786 client = (btstack_context_callback_registration_t*) att_server->indication_requests; 787 btstack_linked_list_remove(&att_server->indication_requests, (btstack_linked_item_t *) client); 788 client->callback(client->context); 789 break; 790 case ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS: 791 client = (btstack_context_callback_registration_t*) att_server->notification_requests; 792 btstack_linked_list_remove(&att_server->notification_requests, (btstack_linked_item_t *) client); 793 client->callback(client->context); 794 break; 795 default: 796 btstack_assert(false); 797 break; 798 } 799 } 800 801 static void att_server_handle_can_send_now(void){ 802 803 hci_con_handle_t last_send_con_handle = HCI_CON_HANDLE_INVALID; 804 hci_connection_t * request_hci_connection = NULL; 805 bool can_send_now = true; 806 uint8_t phase_index; 807 808 for (phase_index = ATT_SERVER_RUN_PHASE_1_REQUESTS; phase_index <= ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS; phase_index++){ 809 att_server_run_phase_t phase = (att_server_run_phase_t) phase_index; 810 hci_con_handle_t skip_connections_until = att_server_last_can_send_now; 811 while (true){ 812 btstack_linked_list_iterator_t it; 813 hci_connections_get_iterator(&it); 814 while(btstack_linked_list_iterator_has_next(&it)){ 815 hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 816 att_server_t * att_server = &connection->att_server; 817 att_connection_t * att_connection = &connection->att_connection; 818 819 bool data_ready = att_server_data_ready_for_phase(att_server, phase); 820 821 // log_debug("phase %u, handle 0x%04x, skip until 0x%04x, data ready %u", phase, att_connection->con_handle, skip_connections_until, data_ready); 822 823 // skip until last sender found (which is also skipped) 824 if (skip_connections_until != HCI_CON_HANDLE_INVALID){ 825 if (data_ready && (request_hci_connection == NULL)){ 826 request_hci_connection = connection; 827 } 828 if (skip_connections_until == att_connection->con_handle){ 829 skip_connections_until = HCI_CON_HANDLE_INVALID; 830 } 831 continue; 832 }; 833 834 if (data_ready){ 835 if (can_send_now){ 836 att_server_trigger_send_for_phase(att_server, att_connection, phase); 837 last_send_con_handle = att_connection->con_handle; 838 can_send_now = att_server_can_send_packet(att_server, att_connection); 839 data_ready = att_server_data_ready_for_phase(att_server, phase); 840 if (data_ready && (request_hci_connection == NULL)){ 841 request_hci_connection = connection; 842 } 843 } else { 844 request_hci_connection = connection; 845 break; 846 } 847 } 848 } 849 850 // stop skipping (handles disconnect by last send connection) 851 skip_connections_until = HCI_CON_HANDLE_INVALID; 852 853 // Exit loop, if we cannot send 854 if (!can_send_now) break; 855 856 // Exit loop, if we can send but there are also no further request 857 if (request_hci_connection == NULL) break; 858 859 // Finally, if we still can send and there are requests, just try again 860 request_hci_connection = NULL; 861 } 862 // update last send con handle for round robin 863 if (last_send_con_handle != HCI_CON_HANDLE_INVALID){ 864 att_server_last_can_send_now = last_send_con_handle; 865 } 866 } 867 868 if (request_hci_connection == NULL) return; 869 870 att_server_t * att_server = &request_hci_connection->att_server; 871 att_connection_t * att_connection = &request_hci_connection->att_connection; 872 att_server_request_can_send_now(att_server, att_connection); 873 } 874 875 static void att_server_handle_att_pdu(att_server_t * att_server, att_connection_t * att_connection, uint8_t * packet, uint16_t size){ 876 877 uint8_t opcode = packet[0u]; 878 uint8_t method = opcode & 0x03fu; 879 bool invalid = method > ATT_MULTIPLE_HANDLE_VALUE_NTF; 880 bool command = (opcode & 0x40u) != 0u; 881 882 // ignore invalid commands 883 if (invalid && command){ 884 return; 885 } 886 887 // handle value indication confirms 888 if ((opcode == ATT_HANDLE_VALUE_CONFIRMATION) && (att_server->value_indication_handle != 0u)){ 889 btstack_run_loop_remove_timer(&att_server->value_indication_timer); 890 uint16_t att_handle = att_server->value_indication_handle; 891 att_server->value_indication_handle = 0u; 892 att_handle_value_indication_notify_client(0u, att_connection->con_handle, att_handle); 893 att_server_request_can_send_now(att_server, att_connection); 894 return; 895 } 896 897 // directly process command 898 // note: signed write cannot be handled directly as authentication needs to be verified 899 if (opcode == ATT_WRITE_COMMAND){ 900 att_handle_request(att_connection, packet, size, NULL); 901 return; 902 } 903 904 // check size 905 if (size > sizeof(att_server->request_buffer)) { 906 log_info("drop att pdu 0x%02x as size %u > att_server->request_buffer %u", packet[0], size, (int) sizeof(att_server->request_buffer)); 907 return; 908 } 909 910 #ifdef ENABLE_LE_SIGNED_WRITE 911 // abort signed write validation if a new request comes in (but finish previous signed write if possible) 912 if (att_server->state == ATT_SERVER_W4_SIGNED_WRITE_VALIDATION){ 913 if (packet[0] == ATT_SIGNED_WRITE_COMMAND){ 914 log_info("skip new signed write request as previous is in validation"); 915 return; 916 } else { 917 log_info("abort signed write validation to process new request"); 918 att_server->state = ATT_SERVER_IDLE; 919 } 920 } 921 #endif 922 // last request still in processing? 923 if (att_server->state != ATT_SERVER_IDLE){ 924 log_info("skip att pdu 0x%02x as server not idle (state %u)", packet[0], att_server->state); 925 return; 926 } 927 928 // store request 929 att_server->state = ATT_SERVER_REQUEST_RECEIVED; 930 att_server->request_size = size; 931 (void)memcpy(att_server->request_buffer, packet, size); 932 933 att_run_for_context(att_server, att_connection); 934 } 935 936 static void att_server_dispatch_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 937 hci_connection_t * hci_connection; 938 att_connection_t * att_connection; 939 att_server_t * att_server; 940 #ifdef ENABLE_GATT_OVER_CLASSIC 941 hci_con_handle_t con_handle; 942 bd_addr_t address; 943 btstack_linked_list_iterator_t it; 944 #endif 945 946 switch (packet_type){ 947 case HCI_EVENT_PACKET: 948 switch (packet[0]){ 949 #ifdef ENABLE_GATT_OVER_CLASSIC 950 case L2CAP_EVENT_CHANNEL_OPENED: 951 con_handle = l2cap_event_channel_opened_get_handle(packet); 952 hci_connection = hci_connection_for_handle(con_handle); 953 if (!hci_connection) break; 954 att_server = &hci_connection->att_server; 955 // store connection info 956 att_server->bearer_type = ATT_BEARER_UNENHANCED_CLASSIC; 957 att_server->peer_addr_type = BD_ADDR_TYPE_ACL; 958 l2cap_event_channel_opened_get_address(packet, att_server->peer_address); 959 att_connection = &hci_connection->att_connection; 960 att_connection->con_handle = con_handle; 961 // reset connection properties 962 att_server->state = ATT_SERVER_IDLE; 963 att_connection->mtu = l2cap_event_channel_opened_get_remote_mtu(packet); 964 att_connection->max_mtu = l2cap_max_mtu(); 965 if (att_connection->max_mtu > ATT_REQUEST_BUFFER_SIZE){ 966 att_connection->max_mtu = ATT_REQUEST_BUFFER_SIZE; 967 } 968 969 log_info("Connection opened %s, l2cap cid %04x, mtu %u", bd_addr_to_str(address), att_server->l2cap_cid, att_connection->mtu); 970 971 // update security params 972 att_connection->encryption_key_size = gap_encryption_key_size(con_handle); 973 att_connection->authenticated = gap_authenticated(con_handle); 974 att_connection->secure_connection = gap_secure_connection(con_handle); 975 log_info("encrypted key size %u, authenticated %u, secure connection %u", 976 att_connection->encryption_key_size, att_connection->authenticated, att_connection->secure_connection); 977 978 // notify connection opened 979 att_emit_connected_event(att_server, att_connection); 980 981 // restore persisten ccc if encrypted 982 if ( gap_security_level(con_handle) >= LEVEL_2){ 983 att_server_persistent_ccc_restore(att_server, att_connection); 984 } 985 // TODO: what to do about le device db? 986 att_server->pairing_active = 0; 987 break; 988 #endif 989 case L2CAP_EVENT_CAN_SEND_NOW: 990 att_server_handle_can_send_now(); 991 break; 992 case ATT_EVENT_MTU_EXCHANGE_COMPLETE: 993 // GATT client has negotiated the mtu for this connection 994 hci_connection = hci_connection_for_handle(channel); 995 if (!hci_connection) break; 996 att_connection = &hci_connection->att_connection; 997 att_connection->mtu = little_endian_read_16(packet, 4); 998 break; 999 default: 1000 break; 1001 } 1002 break; 1003 1004 case ATT_DATA_PACKET: 1005 log_debug("ATT Packet, handle 0x%04x", channel); 1006 hci_connection = hci_connection_for_handle(channel); 1007 if (!hci_connection) break; 1008 1009 att_server = &hci_connection->att_server; 1010 att_connection = &hci_connection->att_connection; 1011 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1012 break; 1013 1014 #ifdef ENABLE_GATT_OVER_CLASSIC 1015 case L2CAP_DATA_PACKET: 1016 hci_connections_get_iterator(&it); 1017 while(btstack_linked_list_iterator_has_next(&it)){ 1018 hci_connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 1019 att_server = &hci_connection->att_server; 1020 att_connection = &hci_connection->att_connection; 1021 if (att_server->l2cap_cid == channel) { 1022 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1023 break; 1024 } 1025 } 1026 break; 1027 #endif 1028 1029 default: 1030 break; 1031 } 1032 } 1033 1034 // --------------------- 1035 // persistent CCC writes 1036 static uint32_t att_server_persistent_ccc_tag_for_index(uint8_t index){ 1037 return ('B' << 24u) | ('T' << 16u) | ('C' << 8u) | index; 1038 } 1039 1040 static void att_server_persistent_ccc_write(hci_con_handle_t con_handle, uint16_t att_handle, uint16_t value){ 1041 // lookup att_server instance 1042 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1043 if (!hci_connection) return; 1044 att_server_t * att_server = &hci_connection->att_server; 1045 int le_device_index = att_server->ir_le_device_db_index; 1046 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); 1047 1048 // check if bonded 1049 if (le_device_index < 0) return; 1050 1051 // get btstack_tlv 1052 const btstack_tlv_t * tlv_impl = NULL; 1053 void * tlv_context; 1054 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1055 if (!tlv_impl) return; 1056 1057 // update ccc tag 1058 int index; 1059 uint32_t highest_seq_nr = 0; 1060 uint32_t lowest_seq_nr = 0; 1061 uint32_t tag_for_lowest_seq_nr = 0; 1062 uint32_t tag_for_empty = 0; 1063 persistent_ccc_entry_t entry; 1064 for (index=0; index<NVN_NUM_GATT_SERVER_CCC; index++){ 1065 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1066 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1067 1068 // empty/invalid tag 1069 if (len != sizeof(persistent_ccc_entry_t)){ 1070 tag_for_empty = tag; 1071 continue; 1072 } 1073 // update highest seq nr 1074 if (entry.seq_nr > highest_seq_nr){ 1075 highest_seq_nr = entry.seq_nr; 1076 } 1077 // find entry with lowest seq nr 1078 if ((tag_for_lowest_seq_nr == 0u) || (entry.seq_nr < lowest_seq_nr)){ 1079 tag_for_lowest_seq_nr = tag; 1080 lowest_seq_nr = entry.seq_nr; 1081 } 1082 1083 if (entry.device_index != le_device_index) continue; 1084 if (entry.att_handle != att_handle) continue; 1085 1086 // found matching entry 1087 if (value != 0){ 1088 // update 1089 if (entry.value == value) { 1090 log_info("CCC Index %u: Up-to-date", index); 1091 return; 1092 } 1093 entry.value = (uint8_t) value; 1094 entry.seq_nr = highest_seq_nr + 1u; 1095 log_info("CCC Index %u: Store", index); 1096 int result = tlv_impl->store_tag(tlv_context, tag, (const uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1097 if (result != 0){ 1098 log_error("Store tag index %u failed", index); 1099 } 1100 } else { 1101 // delete 1102 log_info("CCC Index %u: Delete", index); 1103 tlv_impl->delete_tag(tlv_context, tag); 1104 } 1105 return; 1106 } 1107 1108 log_info("tag_for_empty %"PRIx32", tag_for_lowest_seq_nr %"PRIx32, tag_for_empty, tag_for_lowest_seq_nr); 1109 1110 if (value == 0u){ 1111 // done 1112 return; 1113 } 1114 1115 uint32_t tag_to_use = 0u; 1116 if (tag_for_empty != 0u){ 1117 tag_to_use = tag_for_empty; 1118 } else if (tag_for_lowest_seq_nr != 0){ 1119 tag_to_use = tag_for_lowest_seq_nr; 1120 } else { 1121 // should not happen 1122 return; 1123 } 1124 // store ccc tag 1125 entry.seq_nr = highest_seq_nr + 1u; 1126 entry.device_index = le_device_index; 1127 entry.att_handle = att_handle; 1128 entry.value = (uint8_t) value; 1129 int result = tlv_impl->store_tag(tlv_context, tag_to_use, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1130 if (result != 0){ 1131 log_error("Store tag index %u failed", index); 1132 } 1133 } 1134 1135 static void att_server_persistent_ccc_clear(att_server_t * att_server){ 1136 int le_device_index = att_server->ir_le_device_db_index; 1137 log_info("Clear CCC values of remote %s, le device id %d", bd_addr_to_str(att_server->peer_address), le_device_index); 1138 // check if bonded 1139 if (le_device_index < 0) return; 1140 // get btstack_tlv 1141 const btstack_tlv_t * tlv_impl = NULL; 1142 void * tlv_context; 1143 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1144 if (!tlv_impl) return; 1145 // get all ccc tag 1146 int index; 1147 persistent_ccc_entry_t entry; 1148 for (index=0;index<NVN_NUM_GATT_SERVER_CCC;index++){ 1149 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1150 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1151 if (len != sizeof(persistent_ccc_entry_t)) continue; 1152 if (entry.device_index != le_device_index) continue; 1153 // delete entry 1154 log_info("CCC Index %u: Delete", index); 1155 tlv_impl->delete_tag(tlv_context, tag); 1156 } 1157 } 1158 1159 static void att_server_persistent_ccc_restore(att_server_t * att_server, att_connection_t * att_connection){ 1160 int le_device_index = att_server->ir_le_device_db_index; 1161 log_info("Restore CCC values of remote %s, le device id %d", bd_addr_to_str(att_server->peer_address), le_device_index); 1162 // check if bonded 1163 if (le_device_index < 0) return; 1164 // get btstack_tlv 1165 const btstack_tlv_t * tlv_impl = NULL; 1166 void * tlv_context; 1167 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1168 if (!tlv_impl) return; 1169 // get all ccc tag 1170 int index; 1171 persistent_ccc_entry_t entry; 1172 for (index=0;index<NVN_NUM_GATT_SERVER_CCC;index++){ 1173 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1174 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1175 if (len != sizeof(persistent_ccc_entry_t)) continue; 1176 if (entry.device_index != le_device_index) continue; 1177 // simulate write callback 1178 uint16_t attribute_handle = entry.att_handle; 1179 uint8_t value[2]; 1180 little_endian_store_16(value, 0, entry.value); 1181 att_write_callback_t callback = att_server_write_callback_for_handle(attribute_handle); 1182 if (!callback) continue; 1183 log_info("CCC Index %u: Set Attribute handle 0x%04x to value 0x%04x", index, attribute_handle, entry.value ); 1184 (*callback)(att_connection->con_handle, attribute_handle, ATT_TRANSACTION_MODE_NONE, 0, value, sizeof(value)); 1185 } 1186 } 1187 1188 // persistent CCC writes 1189 // --------------------- 1190 1191 // gatt service management 1192 static att_service_handler_t * att_service_handler_for_handle(uint16_t handle){ 1193 btstack_linked_list_iterator_t it; 1194 btstack_linked_list_iterator_init(&it, &service_handlers); 1195 while (btstack_linked_list_iterator_has_next(&it)){ 1196 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1197 if (handler->start_handle > handle) continue; 1198 if (handler->end_handle < handle) continue; 1199 return handler; 1200 } 1201 return NULL; 1202 } 1203 1204 static att_write_callback_t att_server_write_callback_for_handle(uint16_t handle){ 1205 att_service_handler_t * handler = att_service_handler_for_handle(handle); 1206 if (handler != NULL) return handler->write_callback; 1207 return att_server_client_write_callback; 1208 } 1209 1210 static btstack_packet_handler_t att_server_packet_handler_for_handle(uint16_t handle){ 1211 att_service_handler_t * handler = att_service_handler_for_handle(handle); 1212 if (handler != NULL) return handler->packet_handler; 1213 return att_client_packet_handler; 1214 } 1215 1216 static void att_notify_write_callbacks(hci_con_handle_t con_handle, uint16_t transaction_mode){ 1217 // notify all callbacks 1218 btstack_linked_list_iterator_t it; 1219 btstack_linked_list_iterator_init(&it, &service_handlers); 1220 while (btstack_linked_list_iterator_has_next(&it)){ 1221 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1222 if (!handler->write_callback) continue; 1223 (*handler->write_callback)(con_handle, 0, transaction_mode, 0, NULL, 0); 1224 } 1225 if (!att_server_client_write_callback) return; 1226 (*att_server_client_write_callback)(con_handle, 0, transaction_mode, 0, NULL, 0); 1227 } 1228 1229 // returns first reported error or 0 1230 static uint8_t att_validate_prepared_write(hci_con_handle_t con_handle){ 1231 btstack_linked_list_iterator_t it; 1232 btstack_linked_list_iterator_init(&it, &service_handlers); 1233 while (btstack_linked_list_iterator_has_next(&it)){ 1234 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1235 if (!handler->write_callback) continue; 1236 uint8_t error_code = (*handler->write_callback)(con_handle, 0, ATT_TRANSACTION_MODE_VALIDATE, 0, NULL, 0); 1237 if (error_code != 0u) return error_code; 1238 } 1239 if (!att_server_client_write_callback) return 0; 1240 return (*att_server_client_write_callback)(con_handle, 0, ATT_TRANSACTION_MODE_VALIDATE, 0, NULL, 0); 1241 } 1242 1243 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){ 1244 att_service_handler_t * service = att_service_handler_for_handle(attribute_handle); 1245 att_read_callback_t read_callback = (service != NULL) ? service->read_callback : att_server_client_read_callback; 1246 uint16_t result = 0; 1247 if (read_callback != NULL){ 1248 result = (*read_callback)(con_handle, attribute_handle, offset, buffer, buffer_size); 1249 #ifdef ENABLE_ATT_DELAYED_RESPONSE 1250 if (result == ATT_READ_RESPONSE_PENDING){ 1251 if (service == NULL){ 1252 att_server_flags |= ATT_SERVICE_FLAGS_DELAYED_RESPONSE; 1253 } else { 1254 service->flags |= ATT_SERVICE_FLAGS_DELAYED_RESPONSE; 1255 } 1256 } 1257 #endif 1258 } 1259 return result; 1260 } 1261 1262 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){ 1263 switch (transaction_mode){ 1264 case ATT_TRANSACTION_MODE_VALIDATE: 1265 return att_validate_prepared_write(con_handle); 1266 case ATT_TRANSACTION_MODE_EXECUTE: 1267 case ATT_TRANSACTION_MODE_CANCEL: 1268 att_notify_write_callbacks(con_handle, transaction_mode); 1269 return 0; 1270 default: 1271 break; 1272 } 1273 1274 // track CCC writes 1275 if (att_is_persistent_ccc(attribute_handle) && (offset == 0u) && (buffer_size == 2u)){ 1276 att_server_persistent_ccc_write(con_handle, attribute_handle, little_endian_read_16(buffer, 0)); 1277 } 1278 1279 att_write_callback_t callback = att_server_write_callback_for_handle(attribute_handle); 1280 if (!callback) return 0; 1281 return (*callback)(con_handle, attribute_handle, transaction_mode, offset, buffer, buffer_size); 1282 } 1283 1284 /** 1285 * @brief register read/write callbacks for specific handle range 1286 * @param att_service_handler_t 1287 */ 1288 void att_server_register_service_handler(att_service_handler_t * handler){ 1289 bool att_server_registered = false; 1290 if (att_service_handler_for_handle(handler->start_handle) != NULL){ 1291 att_server_registered = true; 1292 } 1293 1294 if (att_service_handler_for_handle(handler->end_handle) != NULL){ 1295 att_server_registered = true; 1296 } 1297 1298 if (att_server_registered){ 1299 log_error("handler for range 0x%04x-0x%04x already registered", handler->start_handle, handler->end_handle); 1300 return; 1301 } 1302 1303 handler->flags = 0; 1304 btstack_linked_list_add(&service_handlers, (btstack_linked_item_t*) handler); 1305 } 1306 1307 void att_server_init(uint8_t const * db, att_read_callback_t read_callback, att_write_callback_t write_callback){ 1308 1309 // store callbacks 1310 att_server_client_read_callback = read_callback; 1311 att_server_client_write_callback = write_callback; 1312 1313 // register for HCI Events 1314 hci_event_callback_registration.callback = &att_server_event_packet_handler; 1315 hci_add_event_handler(&hci_event_callback_registration); 1316 1317 // register for SM events 1318 sm_event_callback_registration.callback = &att_server_event_packet_handler; 1319 sm_add_event_handler(&sm_event_callback_registration); 1320 1321 // and L2CAP ATT Server PDUs 1322 att_dispatch_register_server(att_server_dispatch_packet_handler); 1323 1324 #ifdef ENABLE_GATT_OVER_CLASSIC 1325 // setup l2cap service 1326 att_dispatch_classic_register_service(); 1327 #endif 1328 1329 att_set_db(db); 1330 att_set_read_callback(att_server_read_callback); 1331 att_set_write_callback(att_server_write_callback); 1332 } 1333 1334 void att_server_register_packet_handler(btstack_packet_handler_t handler){ 1335 att_client_packet_handler = handler; 1336 } 1337 1338 1339 // to be deprecated 1340 int att_server_can_send_packet_now(hci_con_handle_t con_handle){ 1341 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1342 if (!hci_connection) return 0; 1343 att_server_t * att_server = &hci_connection->att_server; 1344 att_connection_t * att_connection = &hci_connection->att_connection; 1345 return att_server_can_send_packet(att_server, att_connection); 1346 } 1347 1348 uint8_t att_server_register_can_send_now_callback(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1349 return att_server_request_to_send_notification(callback_registration, con_handle); 1350 } 1351 1352 void att_server_request_can_send_now_event(hci_con_handle_t con_handle){ 1353 att_client_waiting_for_can_send_registration.callback = &att_emit_can_send_now_event; 1354 att_server_request_to_send_notification(&att_client_waiting_for_can_send_registration, con_handle); 1355 } 1356 // end of deprecated 1357 1358 uint8_t att_server_request_to_send_notification(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1359 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1360 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1361 att_server_t * att_server = &hci_connection->att_server; 1362 att_connection_t * att_connection = &hci_connection->att_connection; 1363 bool added = btstack_linked_list_add_tail(&att_server->notification_requests, (btstack_linked_item_t*) callback_registration); 1364 att_server_request_can_send_now(att_server, att_connection); 1365 if (added){ 1366 return ERROR_CODE_SUCCESS; 1367 } else { 1368 return ERROR_CODE_COMMAND_DISALLOWED; 1369 } 1370 } 1371 1372 uint8_t att_server_request_to_send_indication(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1373 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1374 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1375 att_server_t * att_server = &hci_connection->att_server; 1376 att_connection_t * att_connection = &hci_connection->att_connection; 1377 bool added = btstack_linked_list_add_tail(&att_server->indication_requests, (btstack_linked_item_t*) callback_registration); 1378 att_server_request_can_send_now(att_server, att_connection); 1379 if (added){ 1380 return ERROR_CODE_SUCCESS; 1381 } else { 1382 return ERROR_CODE_COMMAND_DISALLOWED; 1383 } 1384 } 1385 1386 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){ 1387 1388 att_server_t * att_server = NULL; 1389 att_connection_t * att_connection = NULL; 1390 uint8_t * packet_buffer = NULL; 1391 1392 // prefer enhanced bearer 1393 #ifdef ENABLE_GATT_OVER_EATT 1394 att_server_eatt_bearer_t * eatt_bearer = att_server_eatt_bearer_for_con_handle(con_handle); 1395 if (eatt_bearer != NULL){ 1396 att_server = &eatt_bearer->att_server; 1397 att_connection = &eatt_bearer->att_connection; 1398 packet_buffer = eatt_bearer->send_buffer; 1399 } else 1400 #endif 1401 { 1402 hci_connection_t *hci_connection = hci_connection_for_handle(con_handle); 1403 if (hci_connection != NULL) { 1404 att_server = &hci_connection->att_server; 1405 att_connection = &hci_connection->att_connection; 1406 } 1407 } 1408 1409 if (att_server == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1410 if (!att_server_can_send_packet(att_server, att_connection)) return BTSTACK_ACL_BUFFERS_FULL; 1411 1412 if (packet_buffer == NULL){ 1413 l2cap_reserve_packet_buffer(); 1414 packet_buffer = l2cap_get_outgoing_buffer(); 1415 } 1416 1417 *out_att_connection = att_connection; 1418 *out_att_server = att_server; 1419 *out_packet_buffer = packet_buffer; 1420 return ERROR_CODE_SUCCESS; 1421 } 1422 1423 uint8_t att_server_notify(hci_con_handle_t con_handle, uint16_t attribute_handle, const uint8_t *value, uint16_t value_len){ 1424 att_server_t * att_server = NULL; 1425 att_connection_t * att_connection = NULL; 1426 uint8_t * packet_buffer = NULL; 1427 1428 uint8_t status = att_server_prepare_server_message(con_handle, &att_server, &att_connection, &packet_buffer); 1429 if (status != ERROR_CODE_SUCCESS){ 1430 return status; 1431 } 1432 1433 uint16_t size = att_prepare_handle_value_notification(att_connection, attribute_handle, value, value_len, packet_buffer); 1434 1435 return att_server_send_prepared(att_server, att_connection, NULL, size); 1436 } 1437 1438 /** 1439 * @brief notify client about multiple attribute value changes 1440 * @param con_handle 1441 * @param num_attributes 1442 * @param attribute_handles[] 1443 * @param values_data[] 1444 * @param values_len[] 1445 * @return 0 if ok, error otherwise 1446 */ 1447 uint8_t att_server_multiple_notify(hci_con_handle_t con_handle, uint8_t num_attributes, 1448 const uint16_t * attribute_handles, const uint8_t ** values_data, const uint16_t * values_len){ 1449 1450 att_server_t * att_server = NULL; 1451 att_connection_t * att_connection = NULL; 1452 uint8_t * packet_buffer = NULL; 1453 1454 uint8_t status = att_server_prepare_server_message(con_handle, &att_server, &att_connection, &packet_buffer); 1455 if (status != ERROR_CODE_SUCCESS){ 1456 return status; 1457 } 1458 1459 uint16_t size = att_prepare_handle_value_multiple_notification(att_connection, num_attributes, attribute_handles, values_data, values_len, packet_buffer); 1460 1461 return att_server_send_prepared(att_server, att_connection, packet_buffer, size); 1462 } 1463 1464 uint8_t att_server_indicate(hci_con_handle_t con_handle, uint16_t attribute_handle, const uint8_t *value, uint16_t value_len){ 1465 1466 att_server_t * att_server = NULL; 1467 att_connection_t * att_connection = NULL; 1468 uint8_t * packet_buffer = NULL; 1469 1470 uint8_t status = att_server_prepare_server_message(con_handle, &att_server, &att_connection, &packet_buffer); 1471 if (status != ERROR_CODE_SUCCESS){ 1472 return status; 1473 } 1474 1475 if (att_server->value_indication_handle != 0u) { 1476 // free reserved packet buffer 1477 if (att_server->bearer_type == ATT_BEARER_ENHANCED_LE){ 1478 l2cap_release_packet_buffer(); 1479 } 1480 return ATT_HANDLE_VALUE_INDICATION_IN_PROGRESS; 1481 } 1482 1483 // track indication 1484 att_server->value_indication_handle = attribute_handle; 1485 btstack_run_loop_set_timer_handler(&att_server->value_indication_timer, att_handle_value_indication_timeout); 1486 btstack_run_loop_set_timer(&att_server->value_indication_timer, ATT_TRANSACTION_TIMEOUT_MS); 1487 btstack_run_loop_add_timer(&att_server->value_indication_timer); 1488 1489 uint16_t size = att_prepare_handle_value_indication(att_connection, attribute_handle, value, value_len, packet_buffer); 1490 1491 return att_server_send_prepared(att_server, att_connection, NULL, size); 1492 } 1493 1494 uint16_t att_server_get_mtu(hci_con_handle_t con_handle){ 1495 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1496 if (!hci_connection) return 0; 1497 att_connection_t * att_connection = &hci_connection->att_connection; 1498 return att_connection->mtu; 1499 } 1500 1501 void att_server_deinit(void){ 1502 att_server_client_read_callback = NULL; 1503 att_server_client_write_callback = NULL; 1504 att_client_packet_handler = NULL; 1505 service_handlers = NULL; 1506 att_server_flags = 0; 1507 } 1508 1509 #ifdef ENABLE_GATT_OVER_EATT 1510 1511 #define MAX_NR_EATT_CHANNELS 5 1512 1513 static uint16_t att_server_eatt_receive_buffer_size; 1514 static uint16_t att_server_eatt_send_buffer_size; 1515 1516 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_cid(uint16_t cid){ 1517 btstack_linked_list_iterator_t it; 1518 btstack_linked_list_iterator_init(&it, &att_server_eatt_bearer_active); 1519 while(btstack_linked_list_iterator_has_next(&it)){ 1520 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) btstack_linked_list_iterator_next(&it); 1521 if (eatt_bearer->att_server.l2cap_cid == cid) { 1522 return eatt_bearer; 1523 } 1524 } 1525 return NULL; 1526 } 1527 1528 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_con_handle(hci_con_handle_t con_handle){ 1529 btstack_linked_list_iterator_t it; 1530 btstack_linked_list_iterator_init(&it, &att_server_eatt_bearer_active); 1531 while(btstack_linked_list_iterator_has_next(&it)){ 1532 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) btstack_linked_list_iterator_next(&it); 1533 if (eatt_bearer->att_connection.con_handle == con_handle) { 1534 return eatt_bearer; 1535 } 1536 } 1537 return NULL; 1538 } 1539 1540 static void att_server_eatt_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 1541 uint16_t cid; 1542 uint8_t status; 1543 uint16_t remote_mtu; 1544 1545 uint8_t i; 1546 uint8_t num_requested_bearers; 1547 uint8_t num_accepted_bearers; 1548 uint16_t initial_credits = L2CAP_LE_AUTOMATIC_CREDITS; 1549 uint8_t * receive_buffers[MAX_NR_EATT_CHANNELS]; 1550 uint16_t cids[MAX_NR_EATT_CHANNELS]; 1551 att_server_eatt_bearer_t * eatt_bearers[MAX_NR_EATT_CHANNELS]; 1552 att_server_eatt_bearer_t * eatt_bearer; 1553 att_server_t * att_server; 1554 att_connection_t * att_connection; 1555 hci_con_handle_t con_handle; 1556 hci_connection_t * hci_connection; 1557 1558 switch (packet_type) { 1559 1560 case L2CAP_DATA_PACKET: 1561 eatt_bearer = att_server_eatt_bearer_for_cid(channel); 1562 btstack_assert(eatt_bearer != NULL); 1563 att_server = &eatt_bearer->att_server; 1564 att_connection = &eatt_bearer->att_connection; 1565 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1566 break; 1567 1568 case HCI_EVENT_PACKET: 1569 switch (packet[0]) { 1570 1571 case L2CAP_EVENT_CAN_SEND_NOW: 1572 cid = l2cap_event_packet_sent_get_local_cid(packet); 1573 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1574 btstack_assert(eatt_bearer != NULL); 1575 att_server = &eatt_bearer->att_server; 1576 att_connection = &eatt_bearer->att_connection; 1577 // only used for EATT request responses 1578 btstack_assert(att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED); 1579 att_server_process_validated_request(att_server, att_connection, eatt_bearer->send_buffer); 1580 break; 1581 1582 case L2CAP_EVENT_PACKET_SENT: 1583 cid = l2cap_event_packet_sent_get_local_cid(packet); 1584 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1585 btstack_assert(eatt_bearer != NULL); 1586 att_server = &eatt_bearer->att_server; 1587 att_connection = &eatt_bearer->att_connection; 1588 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1589 break; 1590 1591 case L2CAP_EVENT_ECBM_INCOMING_CONNECTION: 1592 cid = l2cap_event_ecbm_incoming_connection_get_local_cid(packet); 1593 1594 // reject if outgoing l2cap connection active, L2CAP/TIM/BV-01-C 1595 con_handle = l2cap_event_ecbm_incoming_connection_get_handle(packet); 1596 hci_connection = hci_connection_for_handle(con_handle); 1597 btstack_assert(hci_connection != NULL); 1598 if (hci_connection->att_server.eatt_outgoing_active) { 1599 hci_connection->att_server.incoming_connection_request = true; 1600 l2cap_ecbm_decline_channels(cid, L2CAP_ECBM_CONNECTION_RESULT_SOME_REFUSED_INSUFFICIENT_RESOURCES_AVAILABLE ); 1601 log_info("Decline incoming connection from %s", bd_addr_to_str(hci_connection->address)); 1602 } else { 1603 num_requested_bearers = l2cap_event_ecbm_incoming_connection_get_num_channels(packet); 1604 for (i = 0; i < num_requested_bearers; i++){ 1605 eatt_bearers[i] = (att_server_eatt_bearer_t *) btstack_linked_list_pop(&att_server_eatt_bearer_pool); 1606 if (eatt_bearers[i] == NULL) { 1607 break; 1608 } 1609 eatt_bearers[i]->att_connection.con_handle = l2cap_event_ecbm_incoming_connection_get_handle(packet); 1610 eatt_bearers[i]->att_server.bearer_type = ATT_BEARER_ENHANCED_LE; 1611 receive_buffers[i] = eatt_bearers[i]->receive_buffer; 1612 btstack_linked_list_add(&att_server_eatt_bearer_active, (btstack_linked_item_t *) eatt_bearers[i]); 1613 } 1614 num_accepted_bearers = i; 1615 status = l2cap_ecbm_accept_channels(cid, num_accepted_bearers, initial_credits, att_server_eatt_receive_buffer_size, receive_buffers, cids); 1616 btstack_assert(status == ERROR_CODE_SUCCESS); 1617 log_info("requested %u, accepted %u", num_requested_bearers, num_accepted_bearers); 1618 for (i=0;i<num_accepted_bearers;i++){ 1619 log_info("eatt l2cap cid: 0x%04x", cids[i]); 1620 eatt_bearers[i]->att_server.l2cap_cid = cids[i]; 1621 } 1622 } 1623 break; 1624 1625 case L2CAP_EVENT_ECBM_CHANNEL_OPENED: 1626 cid = l2cap_event_ecbm_channel_opened_get_local_cid(packet); 1627 status = l2cap_event_ecbm_channel_opened_get_status(packet); 1628 remote_mtu = l2cap_event_ecbm_channel_opened_get_remote_mtu(packet); 1629 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1630 btstack_assert(eatt_bearer != NULL); 1631 eatt_bearer->att_connection.mtu_exchanged = true; 1632 eatt_bearer->att_connection.mtu = remote_mtu; 1633 eatt_bearer->att_connection.max_mtu = remote_mtu; 1634 log_info("L2CAP_EVENT_ECBM_CHANNEL_OPENED - cid 0x%04x mtu %u, status 0x%02x", cid, remote_mtu, status); 1635 break; 1636 1637 case L2CAP_EVENT_ECBM_RECONFIGURED: 1638 break; 1639 1640 case L2CAP_EVENT_CHANNEL_CLOSED: 1641 eatt_bearer = att_server_eatt_bearer_for_cid(l2cap_event_channel_closed_get_local_cid(packet)); 1642 btstack_assert(eatt_bearers != NULL); 1643 1644 // TODO: finalize - abort queued writes 1645 1646 btstack_linked_list_remove(&att_server_eatt_bearer_active, (btstack_linked_item_t *) eatt_bearer); 1647 btstack_linked_list_add(&att_server_eatt_bearer_pool, (btstack_linked_item_t *) eatt_bearer); 1648 break; 1649 default: 1650 break; 1651 } 1652 break; 1653 default: 1654 btstack_unreachable(); 1655 break; 1656 } 1657 } 1658 1659 // create eatt bearers 1660 uint8_t att_server_eatt_init(uint8_t num_eatt_bearers, uint8_t * storage_buffer, uint16_t storage_size){ 1661 uint16_t size_for_structs = num_eatt_bearers * sizeof(att_server_eatt_bearer_t); 1662 if (storage_size < size_for_structs) { 1663 return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED; 1664 } 1665 1666 // TODO: The minimum ATT_MTU for an Enhanced ATT bearer is 64 octets. 1667 1668 memset(storage_buffer, 0, storage_size); 1669 uint16_t buffer_size_per_bearer = ((storage_size - size_for_structs) / num_eatt_bearers); 1670 att_server_eatt_receive_buffer_size = buffer_size_per_bearer / 2; 1671 att_server_eatt_send_buffer_size = buffer_size_per_bearer / 2; 1672 uint8_t * bearer_buffer = &storage_buffer[size_for_structs]; 1673 uint8_t i; 1674 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) storage_buffer; 1675 log_info("%u EATT bearers with receive buffer size %u", 1676 num_eatt_bearers, att_server_eatt_receive_buffer_size); 1677 for (i=0;i<num_eatt_bearers;i++){ 1678 eatt_bearer->att_connection.con_handle = HCI_CON_HANDLE_INVALID; 1679 eatt_bearer->receive_buffer = bearer_buffer; 1680 bearer_buffer += att_server_eatt_receive_buffer_size; 1681 eatt_bearer->send_buffer = bearer_buffer; 1682 bearer_buffer += att_server_eatt_send_buffer_size; 1683 btstack_linked_list_add(&att_server_eatt_bearer_pool, (btstack_linked_item_t *) eatt_bearer); 1684 eatt_bearer++; 1685 } 1686 // TODO: define minimum EATT MTU 1687 l2cap_ecbm_register_service(att_server_eatt_handler, BLUETOOTH_PSM_EATT, 64, 0, false); 1688 1689 return 0; 1690 } 1691 #endif 1692