1 /* 2 * Copyright (C) 2014 BlueKitchen GmbH 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 4. Any redistribution, use, or modification is done solely for 17 * personal benefit and not for any commercial purpose or for 18 * monetary gain. 19 * 20 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN 24 * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Please inquire about commercial licensing options at 34 * [email protected] 35 * 36 */ 37 38 #define BTSTACK_FILE__ "att_server.c" 39 40 41 // 42 // ATT Server Globals 43 // 44 45 #include <stdint.h> 46 #include <string.h> 47 #include <inttypes.h> 48 49 #include "btstack_config.h" 50 51 #include "ble/att_dispatch.h" 52 #include "ble/att_db.h" 53 #include "ble/att_server.h" 54 #include "ble/core.h" 55 #include "ble/le_device_db.h" 56 #include "ble/sm.h" 57 #include "btstack_debug.h" 58 #include "btstack_event.h" 59 #include "btstack_memory.h" 60 #include "btstack_run_loop.h" 61 #include "gap.h" 62 #include "hci.h" 63 #include "hci_dump.h" 64 #include "l2cap.h" 65 #include "btstack_tlv.h" 66 #ifdef ENABLE_LE_SIGNED_WRITE 67 #include "ble/sm.h" 68 #include "bluetooth_psm.h" 69 70 #endif 71 72 #ifdef ENABLE_TESTING_SUPPORT 73 #include <stdio.h> 74 #endif 75 76 #ifndef NVN_NUM_GATT_SERVER_CCC 77 #define NVN_NUM_GATT_SERVER_CCC 20 78 #endif 79 80 static void att_run_for_context(att_server_t * att_server, att_connection_t * att_connection); 81 static att_write_callback_t att_server_write_callback_for_handle(uint16_t handle); 82 static btstack_packet_handler_t att_server_packet_handler_for_handle(uint16_t handle); 83 static void att_server_handle_can_send_now(void); 84 static void att_server_persistent_ccc_restore(att_server_t * att_server, att_connection_t * att_connection); 85 static void att_server_persistent_ccc_clear(att_server_t * att_server); 86 static void att_server_handle_att_pdu(att_server_t * att_server, att_connection_t * att_connection, uint8_t * packet, uint16_t size); 87 88 typedef enum { 89 ATT_SERVER_RUN_PHASE_1_REQUESTS = 0, 90 ATT_SERVER_RUN_PHASE_2_INDICATIONS, 91 ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS, 92 } att_server_run_phase_t; 93 94 // 95 typedef struct { 96 uint32_t seq_nr; 97 uint16_t att_handle; 98 uint8_t value; 99 uint8_t device_index; 100 } persistent_ccc_entry_t; 101 102 // global 103 static btstack_packet_callback_registration_t hci_event_callback_registration; 104 static btstack_packet_callback_registration_t sm_event_callback_registration; 105 static btstack_packet_handler_t att_client_packet_handler; 106 static btstack_linked_list_t service_handlers; 107 static btstack_context_callback_registration_t att_client_waiting_for_can_send_registration; 108 109 static att_read_callback_t att_server_client_read_callback; 110 static att_write_callback_t att_server_client_write_callback; 111 112 // round robin 113 static hci_con_handle_t att_server_last_can_send_now = HCI_CON_HANDLE_INVALID; 114 115 #ifdef ENABLE_GATT_OVER_EATT 116 typedef struct { 117 btstack_linked_item_t item; 118 att_server_t att_server; 119 att_connection_t att_connection; 120 uint8_t * receive_buffer; 121 uint8_t * send_buffer; 122 } att_server_eatt_bearer_t; 123 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_con_handle(hci_con_handle_t con_handle); 124 static btstack_linked_list_t att_server_eatt_bearer_pool; 125 static btstack_linked_list_t att_server_eatt_bearer_active; 126 #endif 127 128 #ifdef ENABLE_LE_SIGNED_WRITE 129 static bool att_server_connections_for_state(att_server_state_t state, att_server_t ** att_server_out, att_connection_t ** att_connection_out){ 130 btstack_linked_list_iterator_t it; 131 hci_connections_get_iterator(&it); 132 while(btstack_linked_list_iterator_has_next(&it)){ 133 hci_connection_t * hci_connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 134 if (hci_connection->att_server.state == state) { 135 *att_server_out = &hci_connection->att_server; 136 *att_connection_out = &hci_connection->att_connection; 137 return true; 138 } 139 } 140 141 #ifdef ENABLE_GATT_OVER_EATT 142 btstack_linked_list_iterator_init(&it, &att_server_eatt_bearer_active); 143 while(btstack_linked_list_iterator_has_next(&it)){ 144 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) btstack_linked_list_iterator_next(&it); 145 if (eatt_bearer->att_server.state == state) { 146 *att_server_out = &eatt_bearer->att_server; 147 *att_connection_out = &eatt_bearer->att_connection; 148 return true; 149 } 150 } 151 #endif 152 153 return false; 154 } 155 #endif 156 157 static void att_server_request_can_send_now(att_server_t * att_server, att_connection_t * att_connection ){ 158 switch (att_server->bearer_type){ 159 case ATT_BEARER_UNENHANCED_LE: 160 att_dispatch_server_request_can_send_now_event(att_connection->con_handle); 161 break; 162 #if defined (ENABLE_GATT_OVER_CLASSIC) || defined (ENABLE_GATT_OVER_EATT) 163 #ifdef ENABLE_GATT_OVER_CLASSIC 164 case ATT_BEARER_UNENHANCED_CLASSIC: 165 /* fall through */ 166 #endif 167 #ifdef ENABLE_GATT_OVER_EATT 168 case ATT_BEARER_ENHANCED_LE: 169 /* fall through */ 170 #endif 171 l2cap_request_can_send_now_event(att_server->l2cap_cid); 172 break; 173 #endif 174 default: 175 btstack_unreachable(); 176 break; 177 } 178 } 179 180 static bool att_server_can_send_packet(att_server_t * att_server, att_connection_t * att_connection){ 181 switch (att_server->bearer_type) { 182 case ATT_BEARER_UNENHANCED_LE: 183 return att_dispatch_server_can_send_now(att_connection->con_handle) != 0; 184 #if defined (ENABLE_GATT_OVER_CLASSIC) || defined (ENABLE_GATT_OVER_EATT) 185 #ifdef ENABLE_GATT_OVER_CLASSIC 186 case ATT_BEARER_UNENHANCED_CLASSIC: 187 /* fall through */ 188 #endif 189 #ifdef ENABLE_GATT_OVER_EATT 190 case ATT_BEARER_ENHANCED_LE: 191 #endif 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_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 #ifdef ENABLE_GATT_OVER_CLASSIC 307 bd_addr_t address; 308 btstack_linked_list_iterator_t it; 309 #endif 310 311 switch (packet_type) { 312 313 case HCI_EVENT_PACKET: 314 switch (hci_event_packet_get_type(packet)) { 315 316 #ifdef ENABLE_GATT_OVER_CLASSIC 317 case L2CAP_EVENT_INCOMING_CONNECTION: 318 l2cap_event_incoming_connection_get_address(packet, address); 319 l2cap_accept_connection(channel); 320 log_info("Accept incoming connection from %s", bd_addr_to_str(address)); 321 break; 322 case L2CAP_EVENT_CHANNEL_OPENED: 323 con_handle = l2cap_event_channel_opened_get_handle(packet); 324 hci_connection = hci_connection_for_handle(con_handle); 325 if (!hci_connection) break; 326 att_server = &hci_connection->att_server; 327 // store connection info 328 att_server->bearer_type = ATT_BEARER_UNENHANCED_CLASSIC; 329 att_server->peer_addr_type = BD_ADDR_TYPE_ACL; 330 l2cap_event_channel_opened_get_address(packet, att_server->peer_address); 331 att_connection = &hci_connection->att_connection; 332 att_connection->con_handle = con_handle; 333 att_server->l2cap_cid = l2cap_event_channel_opened_get_local_cid(packet); 334 // reset connection properties 335 att_server->state = ATT_SERVER_IDLE; 336 att_connection->mtu = l2cap_event_channel_opened_get_remote_mtu(packet); 337 att_connection->max_mtu = l2cap_max_mtu(); 338 if (att_connection->max_mtu > ATT_REQUEST_BUFFER_SIZE){ 339 att_connection->max_mtu = ATT_REQUEST_BUFFER_SIZE; 340 } 341 342 log_info("Connection opened %s, l2cap cid %04x, mtu %u", bd_addr_to_str(address), att_server->l2cap_cid, att_connection->mtu); 343 344 // update security params 345 att_connection->encryption_key_size = gap_encryption_key_size(con_handle); 346 att_connection->authenticated = gap_authenticated(con_handle); 347 att_connection->secure_connection = gap_secure_connection(con_handle); 348 log_info("encrypted key size %u, authenticated %u, secure connection %u", 349 att_connection->encryption_key_size, att_connection->authenticated, att_connection->secure_connection); 350 351 // notify connection opened 352 att_emit_connected_event(att_server, att_connection); 353 354 // restore persisten ccc if encrypted 355 if ( gap_security_level(con_handle) >= LEVEL_2){ 356 att_server_persistent_ccc_restore(att_server, att_connection); 357 } 358 // TODO: what to do about le device db? 359 att_server->pairing_active = 0; 360 break; 361 case L2CAP_EVENT_CAN_SEND_NOW: 362 att_server_handle_can_send_now(); 363 break; 364 365 #endif 366 case HCI_EVENT_LE_META: 367 switch (packet[2]) { 368 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE: 369 con_handle = little_endian_read_16(packet, 4); 370 hci_connection = hci_connection_for_handle(con_handle); 371 if (!hci_connection) break; 372 att_server = &hci_connection->att_server; 373 // store connection info 374 att_server->peer_addr_type = packet[7]; 375 reverse_bd_addr(&packet[8], att_server->peer_address); 376 att_connection = &hci_connection->att_connection; 377 att_connection->con_handle = con_handle; 378 // reset connection properties 379 att_server->state = ATT_SERVER_IDLE; 380 att_server->bearer_type = ATT_BEARER_UNENHANCED_LE; 381 att_connection->mtu = ATT_DEFAULT_MTU; 382 att_connection->max_mtu = l2cap_max_le_mtu(); 383 if (att_connection->max_mtu > ATT_REQUEST_BUFFER_SIZE){ 384 att_connection->max_mtu = ATT_REQUEST_BUFFER_SIZE; 385 } 386 att_connection->encryption_key_size = 0u; 387 att_connection->authenticated = 0u; 388 att_connection->authorized = 0u; 389 // workaround: identity resolving can already be complete, at least store result 390 att_server->ir_le_device_db_index = sm_le_device_index(con_handle); 391 att_server->ir_lookup_active = 0u; 392 att_server->pairing_active = 0u; 393 // notify all - old 394 att_emit_event_to_all(packet, size); 395 // notify all - new 396 att_emit_connected_event(att_server, att_connection); 397 break; 398 399 default: 400 break; 401 } 402 break; 403 404 case HCI_EVENT_ENCRYPTION_CHANGE: 405 case HCI_EVENT_ENCRYPTION_CHANGE_V2: 406 case HCI_EVENT_ENCRYPTION_KEY_REFRESH_COMPLETE: 407 // check handle 408 con_handle = little_endian_read_16(packet, 3); 409 hci_connection = hci_connection_for_handle(con_handle); 410 if (!hci_connection) break; 411 if (gap_get_connection_type(con_handle) != GAP_CONNECTION_LE) break; 412 // update security params 413 att_server = &hci_connection->att_server; 414 att_connection = &hci_connection->att_connection; 415 att_connection->encryption_key_size = gap_encryption_key_size(con_handle); 416 att_connection->authenticated = gap_authenticated(con_handle) ? 1 : 0; 417 att_connection->secure_connection = gap_secure_connection(con_handle) ? 1 : 0; 418 log_info("encrypted key size %u, authenticated %u, secure connection %u", 419 att_connection->encryption_key_size, att_connection->authenticated, att_connection->secure_connection); 420 if (hci_event_packet_get_type(packet) == HCI_EVENT_ENCRYPTION_CHANGE){ 421 // restore CCC values when encrypted for LE Connections 422 if (hci_event_encryption_change_get_encryption_enabled(packet) != 0){ 423 att_server_persistent_ccc_restore(att_server, att_connection); 424 } 425 } 426 att_run_for_context(att_server, att_connection); 427 break; 428 429 case HCI_EVENT_DISCONNECTION_COMPLETE: 430 // check handle 431 con_handle = hci_event_disconnection_complete_get_connection_handle(packet); 432 hci_connection = hci_connection_for_handle(con_handle); 433 if (!hci_connection) break; 434 att_server = &hci_connection->att_server; 435 att_connection = &hci_connection->att_connection; 436 att_clear_transaction_queue(att_connection); 437 att_connection->con_handle = 0; 438 att_server->pairing_active = 0; 439 att_server->state = ATT_SERVER_IDLE; 440 if (att_server->value_indication_handle != 0u){ 441 btstack_run_loop_remove_timer(&att_server->value_indication_timer); 442 uint16_t att_handle = att_server->value_indication_handle; 443 att_server->value_indication_handle = 0u; // reset error state 444 att_handle_value_indication_notify_client((uint8_t)ATT_HANDLE_VALUE_INDICATION_DISCONNECT, att_connection->con_handle, att_handle); 445 } 446 // notify all - new 447 att_emit_disconnected_event(con_handle); 448 // notify all - old 449 att_emit_event_to_all(packet, size); 450 break; 451 452 // Identity Resolving 453 case SM_EVENT_IDENTITY_RESOLVING_STARTED: 454 con_handle = sm_event_identity_resolving_started_get_handle(packet); 455 hci_connection = hci_connection_for_handle(con_handle); 456 if (!hci_connection) break; 457 att_server = &hci_connection->att_server; 458 log_info("SM_EVENT_IDENTITY_RESOLVING_STARTED"); 459 att_server->ir_lookup_active = 1; 460 break; 461 case SM_EVENT_IDENTITY_RESOLVING_SUCCEEDED: 462 con_handle = sm_event_identity_created_get_handle(packet); 463 hci_connection = hci_connection_for_handle(con_handle); 464 if (!hci_connection) return; 465 att_connection = &hci_connection->att_connection; 466 att_server = &hci_connection->att_server; 467 att_server->ir_lookup_active = 0; 468 att_server->ir_le_device_db_index = sm_event_identity_resolving_succeeded_get_index(packet); 469 log_info("SM_EVENT_IDENTITY_RESOLVING_SUCCEEDED"); 470 att_run_for_context(att_server, att_connection); 471 break; 472 case SM_EVENT_IDENTITY_RESOLVING_FAILED: 473 con_handle = sm_event_identity_resolving_failed_get_handle(packet); 474 hci_connection = hci_connection_for_handle(con_handle); 475 if (!hci_connection) break; 476 att_connection = &hci_connection->att_connection; 477 att_server = &hci_connection->att_server; 478 log_info("SM_EVENT_IDENTITY_RESOLVING_FAILED"); 479 att_server->ir_lookup_active = 0; 480 att_server->ir_le_device_db_index = -1; 481 att_run_for_context(att_server, att_connection); 482 break; 483 484 // Pairing started - delete stored CCC values 485 // - assumes pairing indicates either new device or re-pairing, in both cases there should be no stored CCC values 486 // - assumes that all events have the con handle as the first field 487 case SM_EVENT_JUST_WORKS_REQUEST: 488 case SM_EVENT_PASSKEY_DISPLAY_NUMBER: 489 case SM_EVENT_PASSKEY_INPUT_NUMBER: 490 case SM_EVENT_NUMERIC_COMPARISON_REQUEST: 491 con_handle = sm_event_just_works_request_get_handle(packet); 492 hci_connection = hci_connection_for_handle(con_handle); 493 if (!hci_connection) break; 494 att_server = &hci_connection->att_server; 495 log_info("SM Pairing started"); 496 att_server->pairing_active = 1; 497 if (att_server->ir_le_device_db_index < 0) break; 498 att_server_persistent_ccc_clear(att_server); 499 // index not valid anymore 500 att_server->ir_le_device_db_index = -1; 501 break; 502 503 // Bonding completed 504 case SM_EVENT_IDENTITY_CREATED: 505 con_handle = sm_event_identity_created_get_handle(packet); 506 hci_connection = hci_connection_for_handle(con_handle); 507 if (!hci_connection) return; 508 att_connection = &hci_connection->att_connection; 509 att_server = &hci_connection->att_server; 510 att_server->pairing_active = 0; 511 att_server->ir_le_device_db_index = sm_event_identity_created_get_index(packet); 512 att_run_for_context(att_server, att_connection); 513 break; 514 515 // Pairing complete (with/without bonding=storing of pairing information) 516 case SM_EVENT_PAIRING_COMPLETE: 517 con_handle = sm_event_pairing_complete_get_handle(packet); 518 hci_connection = hci_connection_for_handle(con_handle); 519 if (!hci_connection) return; 520 att_connection = &hci_connection->att_connection; 521 att_server = &hci_connection->att_server; 522 att_server->pairing_active = 0; 523 att_run_for_context(att_server, att_connection); 524 break; 525 526 // Authorization 527 case SM_EVENT_AUTHORIZATION_RESULT: { 528 con_handle = sm_event_authorization_result_get_handle(packet); 529 hci_connection = hci_connection_for_handle(con_handle); 530 if (!hci_connection) break; 531 att_connection = &hci_connection->att_connection; 532 att_server = &hci_connection->att_server; 533 att_connection->authorized = sm_event_authorization_result_get_authorization_result(packet); 534 att_server_request_can_send_now(att_server, att_connection); 535 break; 536 } 537 default: 538 break; 539 } 540 break; 541 #ifdef ENABLE_GATT_OVER_CLASSIC 542 case L2CAP_DATA_PACKET: 543 hci_connections_get_iterator(&it); 544 while(btstack_linked_list_iterator_has_next(&it)){ 545 hci_connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 546 att_server = &hci_connection->att_server; 547 att_connection = &hci_connection->att_connection; 548 if (att_server->l2cap_cid == channel) { 549 att_server_handle_att_pdu(att_server, att_connection, packet, size); 550 break; 551 } 552 } 553 break; 554 #endif 555 556 default: 557 break; 558 } 559 } 560 561 static uint8_t 562 att_server_send_prepared(const att_server_t *att_server, const att_connection_t *att_connection, uint8_t *buffer, 563 uint16_t size) { 564 uint8_t status = ERROR_CODE_SUCCESS; 565 switch (att_server->bearer_type) { 566 case ATT_BEARER_UNENHANCED_LE: 567 status = l2cap_send_prepared_connectionless(att_connection->con_handle, L2CAP_CID_ATTRIBUTE_PROTOCOL, size); 568 break; 569 #ifdef ENABLE_GATT_OVER_CLASSIC 570 case ATT_BEARER_UNENHANCED_CLASSIC: 571 status = l2cap_send_prepared(att_server->l2cap_cid, size); 572 break; 573 #endif 574 #ifdef ENABLE_GATT_OVER_EATT 575 case ATT_BEARER_ENHANCED_LE: 576 btstack_assert(buffer != NULL); 577 status = l2cap_send(att_server->l2cap_cid, buffer, size); 578 break; 579 #endif 580 default: 581 btstack_unreachable(); 582 break; 583 } 584 return status; 585 } 586 587 #ifdef ENABLE_LE_SIGNED_WRITE 588 static void att_signed_write_handle_cmac_result(uint8_t hash[8]){ 589 att_server_t * att_server = NULL; 590 att_connection_t * att_connection = NULL; 591 bool found = att_server_connections_for_state(ATT_SERVER_W4_SIGNED_WRITE_VALIDATION, &att_server, &att_connection); 592 593 if (found == false){ 594 return; 595 } 596 597 uint8_t hash_flipped[8]; 598 reverse_64(hash, hash_flipped); 599 if (memcmp(hash_flipped, &att_server->request_buffer[att_server->request_size-8], 8) != 0){ 600 log_info("ATT Signed Write, invalid signature"); 601 #ifdef ENABLE_TESTING_SUPPORT 602 printf("ATT Signed Write, invalid signature\n"); 603 #endif 604 att_server->state = ATT_SERVER_IDLE; 605 return; 606 } 607 log_info("ATT Signed Write, valid signature"); 608 #ifdef ENABLE_TESTING_SUPPORT 609 printf("ATT Signed Write, valid signature\n"); 610 #endif 611 612 // update sequence number 613 uint32_t counter_packet = little_endian_read_32(att_server->request_buffer, att_server->request_size-12); 614 le_device_db_remote_counter_set(att_server->ir_le_device_db_index, counter_packet+1); 615 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 616 att_server_request_can_send_now(att_server, att_connection); 617 } 618 #endif 619 620 // pre: att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED 621 // pre: can send now 622 // uses l2cap outgoing buffer if no eatt_buffer provided 623 // returns: 1 if packet was sent 624 static int 625 att_server_process_validated_request(att_server_t *att_server, att_connection_t *att_connection, uint8_t *eatt_buffer) { 626 627 uint8_t * att_response_buffer; 628 if (eatt_buffer != NULL){ 629 att_response_buffer = eatt_buffer; 630 } else { 631 l2cap_reserve_packet_buffer(); 632 att_response_buffer = l2cap_get_outgoing_buffer(); 633 } 634 635 uint16_t att_response_size = 0; 636 // Send Error Response for MTU Request over connection-oriented channel 637 if ((att_server->bearer_type != ATT_BEARER_UNENHANCED_LE) && (att_server->request_buffer[0] == ATT_EXCHANGE_MTU_REQUEST)){ 638 att_response_size = 5; 639 att_response_buffer[0] = ATT_ERROR_RESPONSE; 640 att_response_buffer[1] = ATT_EXCHANGE_MTU_REQUEST; 641 att_response_buffer[2] = 0; 642 att_response_buffer[3] = 0; 643 att_response_buffer[4] = ATT_ERROR_REQUEST_NOT_SUPPORTED; 644 } else { 645 att_response_size = att_handle_request(att_connection, att_server->request_buffer, att_server->request_size, att_response_buffer); 646 } 647 648 #ifdef ENABLE_ATT_DELAYED_RESPONSE 649 if ((att_response_size == ATT_READ_RESPONSE_PENDING) || (att_response_size == ATT_INTERNAL_WRITE_RESPONSE_PENDING)){ 650 // update state 651 att_server->state = ATT_SERVER_RESPONSE_PENDING; 652 653 // callback with handle ATT_READ_RESPONSE_PENDING for reads 654 if (att_response_size == ATT_READ_RESPONSE_PENDING){ 655 att_server_client_read_callback(att_connection->con_handle, ATT_READ_RESPONSE_PENDING, 0, NULL, 0); 656 } 657 658 // free reserved buffer 659 if (eatt_buffer == NULL){ 660 l2cap_release_packet_buffer(); 661 } 662 return 0; 663 } 664 #endif 665 666 // intercept "insufficient authorization" for authenticated connections to allow for user authorization 667 if ((att_response_size >= 4u) 668 && (att_response_buffer[0] == ATT_ERROR_RESPONSE) 669 && (att_response_buffer[4] == ATT_ERROR_INSUFFICIENT_AUTHORIZATION) 670 && (att_connection->authenticated != 0u)){ 671 672 switch (gap_authorization_state(att_connection->con_handle)){ 673 case AUTHORIZATION_UNKNOWN: 674 if (eatt_buffer == NULL){ 675 l2cap_release_packet_buffer(); 676 } 677 sm_request_pairing(att_connection->con_handle); 678 return 0; 679 case AUTHORIZATION_PENDING: 680 if (eatt_buffer == NULL){ 681 l2cap_release_packet_buffer(); 682 } 683 return 0; 684 default: 685 break; 686 } 687 } 688 689 att_server->state = ATT_SERVER_IDLE; 690 if (att_response_size == 0u) { 691 if (eatt_buffer == NULL){ 692 l2cap_release_packet_buffer(); 693 } 694 return 0; 695 } 696 697 (void) att_server_send_prepared(att_server, att_connection, eatt_buffer, att_response_size); 698 699 // notify client about MTU exchange result 700 if (att_response_buffer[0] == ATT_EXCHANGE_MTU_RESPONSE){ 701 att_emit_mtu_event(att_connection->con_handle, att_connection->mtu); 702 } 703 return 1; 704 } 705 706 #ifdef ENABLE_ATT_DELAYED_RESPONSE 707 uint8_t att_server_response_ready(hci_con_handle_t con_handle){ 708 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 709 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 710 att_server_t * att_server = &hci_connection->att_server; 711 att_connection_t * att_connection = &hci_connection->att_connection; 712 if (att_server->state != ATT_SERVER_RESPONSE_PENDING) return ERROR_CODE_COMMAND_DISALLOWED; 713 714 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 715 att_server_request_can_send_now(att_server, att_connection); 716 return ERROR_CODE_SUCCESS; 717 } 718 #endif 719 720 static void att_run_for_context(att_server_t * att_server, att_connection_t * att_connection){ 721 switch (att_server->state){ 722 case ATT_SERVER_REQUEST_RECEIVED: 723 switch (att_server->bearer_type){ 724 case ATT_BEARER_UNENHANCED_LE: 725 // wait until re-encryption as central is complete 726 if (gap_reconnect_security_setup_active(att_connection->con_handle)) { 727 return; 728 }; 729 break; 730 #if defined(ENABLE_GATT_OVER_CLASSIC) || defined (ENABLE_GATT_OVER_EATT) 731 #ifdef ENABLE_GATT_OVER_CLASSIC 732 case ATT_BEARER_UNENHANCED_CLASSIC: 733 /* fall through */ 734 #endif 735 #ifdef ENABLE_GATT_OVER_EATT 736 case ATT_BEARER_ENHANCED_LE: 737 #endif 738 // ok 739 break; 740 #endif 741 default: 742 btstack_unreachable(); 743 break; 744 } 745 746 // wait until pairing is complete 747 if (att_server->pairing_active) break; 748 749 #ifdef ENABLE_LE_SIGNED_WRITE 750 if (att_server->request_buffer[0] == ATT_SIGNED_WRITE_COMMAND){ 751 log_info("ATT Signed Write!"); 752 if (!sm_cmac_ready()) { 753 log_info("ATT Signed Write, sm_cmac engine not ready. Abort"); 754 att_server->state = ATT_SERVER_IDLE; 755 return; 756 } 757 if (att_server->request_size < (3 + 12)) { 758 log_info("ATT Signed Write, request to short. Abort."); 759 att_server->state = ATT_SERVER_IDLE; 760 return; 761 } 762 if (att_server->ir_lookup_active){ 763 return; 764 } 765 if (att_server->ir_le_device_db_index < 0){ 766 log_info("ATT Signed Write, CSRK not available"); 767 att_server->state = ATT_SERVER_IDLE; 768 return; 769 } 770 771 // check counter 772 uint32_t counter_packet = little_endian_read_32(att_server->request_buffer, att_server->request_size-12); 773 uint32_t counter_db = le_device_db_remote_counter_get(att_server->ir_le_device_db_index); 774 log_info("ATT Signed Write, DB counter %"PRIu32", packet counter %"PRIu32, counter_db, counter_packet); 775 if (counter_packet < counter_db){ 776 log_info("ATT Signed Write, db reports higher counter, abort"); 777 att_server->state = ATT_SERVER_IDLE; 778 return; 779 } 780 781 // signature is { sequence counter, secure hash } 782 sm_key_t csrk; 783 le_device_db_remote_csrk_get(att_server->ir_le_device_db_index, csrk); 784 att_server->state = ATT_SERVER_W4_SIGNED_WRITE_VALIDATION; 785 log_info("Orig Signature: "); 786 log_info_hexdump( &att_server->request_buffer[att_server->request_size-8], 8); 787 uint16_t attribute_handle = little_endian_read_16(att_server->request_buffer, 1); 788 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); 789 return; 790 } 791 #endif 792 // move on 793 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 794 att_server_request_can_send_now(att_server, att_connection); 795 break; 796 797 default: 798 break; 799 } 800 } 801 802 static bool att_server_data_ready_for_phase(att_server_t * att_server, att_server_run_phase_t phase){ 803 switch (phase){ 804 case ATT_SERVER_RUN_PHASE_1_REQUESTS: 805 return att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 806 case ATT_SERVER_RUN_PHASE_2_INDICATIONS: 807 return (!btstack_linked_list_empty(&att_server->indication_requests) && (att_server->value_indication_handle == 0u)); 808 case ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS: 809 return (!btstack_linked_list_empty(&att_server->notification_requests)); 810 default: 811 btstack_assert(false); 812 return false; 813 } 814 } 815 816 static void att_server_trigger_send_for_phase(att_server_t * att_server, att_connection_t * att_connection, att_server_run_phase_t phase){ 817 btstack_context_callback_registration_t * client; 818 switch (phase){ 819 case ATT_SERVER_RUN_PHASE_1_REQUESTS: 820 att_server_process_validated_request(att_server, att_connection, NULL); 821 break; 822 case ATT_SERVER_RUN_PHASE_2_INDICATIONS: 823 client = (btstack_context_callback_registration_t*) att_server->indication_requests; 824 btstack_linked_list_remove(&att_server->indication_requests, (btstack_linked_item_t *) client); 825 client->callback(client->context); 826 break; 827 case ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS: 828 client = (btstack_context_callback_registration_t*) att_server->notification_requests; 829 btstack_linked_list_remove(&att_server->notification_requests, (btstack_linked_item_t *) client); 830 client->callback(client->context); 831 break; 832 default: 833 btstack_assert(false); 834 break; 835 } 836 } 837 838 static void att_server_handle_can_send_now(void){ 839 840 hci_con_handle_t last_send_con_handle = HCI_CON_HANDLE_INVALID; 841 hci_connection_t * request_hci_connection = NULL; 842 bool can_send_now = true; 843 uint8_t phase_index; 844 845 for (phase_index = ATT_SERVER_RUN_PHASE_1_REQUESTS; phase_index <= ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS; phase_index++){ 846 att_server_run_phase_t phase = (att_server_run_phase_t) phase_index; 847 hci_con_handle_t skip_connections_until = att_server_last_can_send_now; 848 while (true){ 849 btstack_linked_list_iterator_t it; 850 hci_connections_get_iterator(&it); 851 while(btstack_linked_list_iterator_has_next(&it)){ 852 hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 853 att_server_t * att_server = &connection->att_server; 854 att_connection_t * att_connection = &connection->att_connection; 855 856 bool data_ready = att_server_data_ready_for_phase(att_server, phase); 857 858 // log_debug("phase %u, handle 0x%04x, skip until 0x%04x, data ready %u", phase, att_connection->con_handle, skip_connections_until, data_ready); 859 860 // skip until last sender found (which is also skipped) 861 if (skip_connections_until != HCI_CON_HANDLE_INVALID){ 862 if (data_ready && (request_hci_connection == NULL)){ 863 request_hci_connection = connection; 864 } 865 if (skip_connections_until == att_connection->con_handle){ 866 skip_connections_until = HCI_CON_HANDLE_INVALID; 867 } 868 continue; 869 }; 870 871 if (data_ready){ 872 if (can_send_now){ 873 att_server_trigger_send_for_phase(att_server, att_connection, phase); 874 last_send_con_handle = att_connection->con_handle; 875 can_send_now = att_server_can_send_packet(att_server, att_connection); 876 data_ready = att_server_data_ready_for_phase(att_server, phase); 877 if (data_ready && (request_hci_connection == NULL)){ 878 request_hci_connection = connection; 879 } 880 } else { 881 request_hci_connection = connection; 882 break; 883 } 884 } 885 } 886 887 // stop skipping (handles disconnect by last send connection) 888 skip_connections_until = HCI_CON_HANDLE_INVALID; 889 890 // Exit loop, if we cannot send 891 if (!can_send_now) break; 892 893 // Exit loop, if we can send but there are also no further request 894 if (request_hci_connection == NULL) break; 895 896 // Finally, if we still can send and there are requests, just try again 897 request_hci_connection = NULL; 898 } 899 // update last send con handle for round robin 900 if (last_send_con_handle != HCI_CON_HANDLE_INVALID){ 901 att_server_last_can_send_now = last_send_con_handle; 902 } 903 } 904 905 if (request_hci_connection == NULL) return; 906 907 att_server_t * att_server = &request_hci_connection->att_server; 908 att_connection_t * att_connection = &request_hci_connection->att_connection; 909 att_server_request_can_send_now(att_server, att_connection); 910 } 911 912 static void att_server_handle_att_pdu(att_server_t * att_server, att_connection_t * att_connection, uint8_t * packet, uint16_t size){ 913 914 uint8_t opcode = packet[0u]; 915 uint8_t method = opcode & 0x03fu; 916 bool invalid = method > ATT_MULTIPLE_HANDLE_VALUE_NTF; 917 bool command = (opcode & 0x40u) != 0u; 918 919 // ignore invalid commands 920 if (invalid && command){ 921 return; 922 } 923 924 // handle value indication confirms 925 if ((opcode == ATT_HANDLE_VALUE_CONFIRMATION) && (att_server->value_indication_handle != 0u)){ 926 btstack_run_loop_remove_timer(&att_server->value_indication_timer); 927 uint16_t att_handle = att_server->value_indication_handle; 928 att_server->value_indication_handle = 0u; 929 att_handle_value_indication_notify_client(0u, att_connection->con_handle, att_handle); 930 att_server_request_can_send_now(att_server, att_connection); 931 return; 932 } 933 934 // directly process command 935 // note: signed write cannot be handled directly as authentication needs to be verified 936 if (opcode == ATT_WRITE_COMMAND){ 937 att_handle_request(att_connection, packet, size, NULL); 938 return; 939 } 940 941 // check size 942 if (size > sizeof(att_server->request_buffer)) { 943 log_info("drop att pdu 0x%02x as size %u > att_server->request_buffer %u", packet[0], size, (int) sizeof(att_server->request_buffer)); 944 return; 945 } 946 947 #ifdef ENABLE_LE_SIGNED_WRITE 948 // abort signed write validation if a new request comes in (but finish previous signed write if possible) 949 if (att_server->state == ATT_SERVER_W4_SIGNED_WRITE_VALIDATION){ 950 if (packet[0] == ATT_SIGNED_WRITE_COMMAND){ 951 log_info("skip new signed write request as previous is in validation"); 952 return; 953 } else { 954 log_info("abort signed write validation to process new request"); 955 att_server->state = ATT_SERVER_IDLE; 956 } 957 } 958 #endif 959 // last request still in processing? 960 if (att_server->state != ATT_SERVER_IDLE){ 961 log_info("skip att pdu 0x%02x as server not idle (state %u)", packet[0], att_server->state); 962 return; 963 } 964 965 // store request 966 att_server->state = ATT_SERVER_REQUEST_RECEIVED; 967 att_server->request_size = size; 968 (void)memcpy(att_server->request_buffer, packet, size); 969 970 att_run_for_context(att_server, att_connection); 971 } 972 973 static void att_packet_handler(uint8_t packet_type, uint16_t handle, uint8_t *packet, uint16_t size){ 974 hci_connection_t * hci_connection; 975 att_connection_t * att_connection; 976 att_server_t * att_server; 977 978 switch (packet_type){ 979 case HCI_EVENT_PACKET: 980 switch (packet[0]){ 981 case L2CAP_EVENT_CAN_SEND_NOW: 982 att_server_handle_can_send_now(); 983 break; 984 case ATT_EVENT_MTU_EXCHANGE_COMPLETE: 985 // GATT client has negotiated the mtu for this connection 986 hci_connection = hci_connection_for_handle(handle); 987 if (!hci_connection) break; 988 att_connection = &hci_connection->att_connection; 989 att_connection->mtu = little_endian_read_16(packet, 4); 990 break; 991 default: 992 break; 993 } 994 break; 995 996 case ATT_DATA_PACKET: 997 log_debug("ATT Packet, handle 0x%04x", handle); 998 hci_connection = hci_connection_for_handle(handle); 999 if (!hci_connection) break; 1000 1001 att_server = &hci_connection->att_server; 1002 att_connection = &hci_connection->att_connection; 1003 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1004 break; 1005 1006 default: 1007 break; 1008 } 1009 } 1010 1011 // --------------------- 1012 // persistent CCC writes 1013 static uint32_t att_server_persistent_ccc_tag_for_index(uint8_t index){ 1014 return ('B' << 24u) | ('T' << 16u) | ('C' << 8u) | index; 1015 } 1016 1017 static void att_server_persistent_ccc_write(hci_con_handle_t con_handle, uint16_t att_handle, uint16_t value){ 1018 // lookup att_server instance 1019 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1020 if (!hci_connection) return; 1021 att_server_t * att_server = &hci_connection->att_server; 1022 int le_device_index = att_server->ir_le_device_db_index; 1023 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); 1024 1025 // check if bonded 1026 if (le_device_index < 0) return; 1027 1028 // get btstack_tlv 1029 const btstack_tlv_t * tlv_impl = NULL; 1030 void * tlv_context; 1031 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1032 if (!tlv_impl) return; 1033 1034 // update ccc tag 1035 int index; 1036 uint32_t highest_seq_nr = 0; 1037 uint32_t lowest_seq_nr = 0; 1038 uint32_t tag_for_lowest_seq_nr = 0; 1039 uint32_t tag_for_empty = 0; 1040 persistent_ccc_entry_t entry; 1041 for (index=0; index<NVN_NUM_GATT_SERVER_CCC; index++){ 1042 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1043 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1044 1045 // empty/invalid tag 1046 if (len != sizeof(persistent_ccc_entry_t)){ 1047 tag_for_empty = tag; 1048 continue; 1049 } 1050 // update highest seq nr 1051 if (entry.seq_nr > highest_seq_nr){ 1052 highest_seq_nr = entry.seq_nr; 1053 } 1054 // find entry with lowest seq nr 1055 if ((tag_for_lowest_seq_nr == 0u) || (entry.seq_nr < lowest_seq_nr)){ 1056 tag_for_lowest_seq_nr = tag; 1057 lowest_seq_nr = entry.seq_nr; 1058 } 1059 1060 if (entry.device_index != le_device_index) continue; 1061 if (entry.att_handle != att_handle) continue; 1062 1063 // found matching entry 1064 if (value != 0){ 1065 // update 1066 if (entry.value == value) { 1067 log_info("CCC Index %u: Up-to-date", index); 1068 return; 1069 } 1070 entry.value = (uint8_t) value; 1071 entry.seq_nr = highest_seq_nr + 1u; 1072 log_info("CCC Index %u: Store", index); 1073 int result = tlv_impl->store_tag(tlv_context, tag, (const uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1074 if (result != 0){ 1075 log_error("Store tag index %u failed", index); 1076 } 1077 } else { 1078 // delete 1079 log_info("CCC Index %u: Delete", index); 1080 tlv_impl->delete_tag(tlv_context, tag); 1081 } 1082 return; 1083 } 1084 1085 log_info("tag_for_empty %"PRIx32", tag_for_lowest_seq_nr %"PRIx32, tag_for_empty, tag_for_lowest_seq_nr); 1086 1087 if (value == 0u){ 1088 // done 1089 return; 1090 } 1091 1092 uint32_t tag_to_use = 0u; 1093 if (tag_for_empty != 0u){ 1094 tag_to_use = tag_for_empty; 1095 } else if (tag_for_lowest_seq_nr){ 1096 tag_to_use = tag_for_lowest_seq_nr; 1097 } else { 1098 // should not happen 1099 return; 1100 } 1101 // store ccc tag 1102 entry.seq_nr = highest_seq_nr + 1u; 1103 entry.device_index = le_device_index; 1104 entry.att_handle = att_handle; 1105 entry.value = (uint8_t) value; 1106 int result = tlv_impl->store_tag(tlv_context, tag_to_use, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1107 if (result != 0){ 1108 log_error("Store tag index %u failed", index); 1109 } 1110 } 1111 1112 static void att_server_persistent_ccc_clear(att_server_t * att_server){ 1113 int le_device_index = att_server->ir_le_device_db_index; 1114 log_info("Clear CCC values of remote %s, le device id %d", bd_addr_to_str(att_server->peer_address), le_device_index); 1115 // check if bonded 1116 if (le_device_index < 0) return; 1117 // get btstack_tlv 1118 const btstack_tlv_t * tlv_impl = NULL; 1119 void * tlv_context; 1120 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1121 if (!tlv_impl) return; 1122 // get all ccc tag 1123 int index; 1124 persistent_ccc_entry_t entry; 1125 for (index=0;index<NVN_NUM_GATT_SERVER_CCC;index++){ 1126 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1127 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1128 if (len != sizeof(persistent_ccc_entry_t)) continue; 1129 if (entry.device_index != le_device_index) continue; 1130 // delete entry 1131 log_info("CCC Index %u: Delete", index); 1132 tlv_impl->delete_tag(tlv_context, tag); 1133 } 1134 } 1135 1136 static void att_server_persistent_ccc_restore(att_server_t * att_server, att_connection_t * att_connection){ 1137 int le_device_index = att_server->ir_le_device_db_index; 1138 log_info("Restore CCC values of remote %s, le device id %d", bd_addr_to_str(att_server->peer_address), le_device_index); 1139 // check if bonded 1140 if (le_device_index < 0) return; 1141 // get btstack_tlv 1142 const btstack_tlv_t * tlv_impl = NULL; 1143 void * tlv_context; 1144 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1145 if (!tlv_impl) return; 1146 // get all ccc tag 1147 int index; 1148 persistent_ccc_entry_t entry; 1149 for (index=0;index<NVN_NUM_GATT_SERVER_CCC;index++){ 1150 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1151 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1152 if (len != sizeof(persistent_ccc_entry_t)) continue; 1153 if (entry.device_index != le_device_index) continue; 1154 // simulate write callback 1155 uint16_t attribute_handle = entry.att_handle; 1156 uint8_t value[2]; 1157 little_endian_store_16(value, 0, entry.value); 1158 att_write_callback_t callback = att_server_write_callback_for_handle(attribute_handle); 1159 if (!callback) continue; 1160 log_info("CCC Index %u: Set Attribute handle 0x%04x to value 0x%04x", index, attribute_handle, entry.value ); 1161 (*callback)(att_connection->con_handle, attribute_handle, ATT_TRANSACTION_MODE_NONE, 0, value, sizeof(value)); 1162 } 1163 } 1164 1165 // persistent CCC writes 1166 // --------------------- 1167 1168 // gatt service management 1169 static att_service_handler_t * att_service_handler_for_handle(uint16_t handle){ 1170 btstack_linked_list_iterator_t it; 1171 btstack_linked_list_iterator_init(&it, &service_handlers); 1172 while (btstack_linked_list_iterator_has_next(&it)){ 1173 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1174 if (handler->start_handle > handle) continue; 1175 if (handler->end_handle < handle) continue; 1176 return handler; 1177 } 1178 return NULL; 1179 } 1180 static att_read_callback_t att_server_read_callback_for_handle(uint16_t handle){ 1181 att_service_handler_t * handler = att_service_handler_for_handle(handle); 1182 if (handler != NULL) return handler->read_callback; 1183 return att_server_client_read_callback; 1184 } 1185 1186 static att_write_callback_t att_server_write_callback_for_handle(uint16_t handle){ 1187 att_service_handler_t * handler = att_service_handler_for_handle(handle); 1188 if (handler != NULL) return handler->write_callback; 1189 return att_server_client_write_callback; 1190 } 1191 1192 static btstack_packet_handler_t att_server_packet_handler_for_handle(uint16_t handle){ 1193 att_service_handler_t * handler = att_service_handler_for_handle(handle); 1194 if (handler != NULL) return handler->packet_handler; 1195 return att_client_packet_handler; 1196 } 1197 1198 static void att_notify_write_callbacks(hci_con_handle_t con_handle, uint16_t transaction_mode){ 1199 // notify all callbacks 1200 btstack_linked_list_iterator_t it; 1201 btstack_linked_list_iterator_init(&it, &service_handlers); 1202 while (btstack_linked_list_iterator_has_next(&it)){ 1203 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1204 if (!handler->write_callback) continue; 1205 (*handler->write_callback)(con_handle, 0, transaction_mode, 0, NULL, 0); 1206 } 1207 if (!att_server_client_write_callback) return; 1208 (*att_server_client_write_callback)(con_handle, 0, transaction_mode, 0, NULL, 0); 1209 } 1210 1211 // returns first reported error or 0 1212 static uint8_t att_validate_prepared_write(hci_con_handle_t con_handle){ 1213 btstack_linked_list_iterator_t it; 1214 btstack_linked_list_iterator_init(&it, &service_handlers); 1215 while (btstack_linked_list_iterator_has_next(&it)){ 1216 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1217 if (!handler->write_callback) continue; 1218 uint8_t error_code = (*handler->write_callback)(con_handle, 0, ATT_TRANSACTION_MODE_VALIDATE, 0, NULL, 0); 1219 if (error_code != 0u) return error_code; 1220 } 1221 if (!att_server_client_write_callback) return 0; 1222 return (*att_server_client_write_callback)(con_handle, 0, ATT_TRANSACTION_MODE_VALIDATE, 0, NULL, 0); 1223 } 1224 1225 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){ 1226 att_read_callback_t callback = att_server_read_callback_for_handle(attribute_handle); 1227 if (!callback) return 0; 1228 return (*callback)(con_handle, attribute_handle, offset, buffer, buffer_size); 1229 } 1230 1231 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){ 1232 switch (transaction_mode){ 1233 case ATT_TRANSACTION_MODE_VALIDATE: 1234 return att_validate_prepared_write(con_handle); 1235 case ATT_TRANSACTION_MODE_EXECUTE: 1236 case ATT_TRANSACTION_MODE_CANCEL: 1237 att_notify_write_callbacks(con_handle, transaction_mode); 1238 return 0; 1239 default: 1240 break; 1241 } 1242 1243 // track CCC writes 1244 if (att_is_persistent_ccc(attribute_handle) && (offset == 0u) && (buffer_size == 2u)){ 1245 att_server_persistent_ccc_write(con_handle, attribute_handle, little_endian_read_16(buffer, 0)); 1246 } 1247 1248 att_write_callback_t callback = att_server_write_callback_for_handle(attribute_handle); 1249 if (!callback) return 0; 1250 return (*callback)(con_handle, attribute_handle, transaction_mode, offset, buffer, buffer_size); 1251 } 1252 1253 /** 1254 * @brief register read/write callbacks for specific handle range 1255 * @param att_service_handler_t 1256 */ 1257 void att_server_register_service_handler(att_service_handler_t * handler){ 1258 bool att_server_registered = false; 1259 if (att_service_handler_for_handle(handler->start_handle)){ 1260 att_server_registered = true; 1261 } 1262 1263 if (att_service_handler_for_handle(handler->end_handle)){ 1264 att_server_registered = true; 1265 } 1266 1267 if (att_server_registered){ 1268 log_error("handler for range 0x%04x-0x%04x already registered", handler->start_handle, handler->end_handle); 1269 return; 1270 } 1271 btstack_linked_list_add(&service_handlers, (btstack_linked_item_t*) handler); 1272 } 1273 1274 void att_server_init(uint8_t const * db, att_read_callback_t read_callback, att_write_callback_t write_callback){ 1275 1276 // store callbacks 1277 att_server_client_read_callback = read_callback; 1278 att_server_client_write_callback = write_callback; 1279 1280 // register for HCI Events 1281 hci_event_callback_registration.callback = &att_event_packet_handler; 1282 hci_add_event_handler(&hci_event_callback_registration); 1283 1284 // register for SM events 1285 sm_event_callback_registration.callback = &att_event_packet_handler; 1286 sm_add_event_handler(&sm_event_callback_registration); 1287 1288 // and L2CAP ATT Server PDUs 1289 att_dispatch_register_server(att_packet_handler); 1290 1291 #ifdef ENABLE_GATT_OVER_CLASSIC 1292 // setup l2cap service 1293 l2cap_register_service(&att_event_packet_handler, PSM_ATT, 0xffff, gap_get_security_level()); 1294 #endif 1295 1296 att_set_db(db); 1297 att_set_read_callback(att_server_read_callback); 1298 att_set_write_callback(att_server_write_callback); 1299 } 1300 1301 void att_server_register_packet_handler(btstack_packet_handler_t handler){ 1302 att_client_packet_handler = handler; 1303 } 1304 1305 1306 // to be deprecated 1307 int att_server_can_send_packet_now(hci_con_handle_t con_handle){ 1308 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1309 if (!hci_connection) return 0; 1310 att_server_t * att_server = &hci_connection->att_server; 1311 att_connection_t * att_connection = &hci_connection->att_connection; 1312 return att_server_can_send_packet(att_server, att_connection); 1313 } 1314 1315 uint8_t att_server_register_can_send_now_callback(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1316 return att_server_request_to_send_notification(callback_registration, con_handle); 1317 } 1318 1319 void att_server_request_can_send_now_event(hci_con_handle_t con_handle){ 1320 att_client_waiting_for_can_send_registration.callback = &att_emit_can_send_now_event; 1321 att_server_request_to_send_notification(&att_client_waiting_for_can_send_registration, con_handle); 1322 } 1323 // end of deprecated 1324 1325 uint8_t att_server_request_to_send_notification(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1326 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1327 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1328 att_server_t * att_server = &hci_connection->att_server; 1329 att_connection_t * att_connection = &hci_connection->att_connection; 1330 bool added = btstack_linked_list_add_tail(&att_server->notification_requests, (btstack_linked_item_t*) callback_registration); 1331 att_server_request_can_send_now(att_server, att_connection); 1332 if (added){ 1333 return ERROR_CODE_SUCCESS; 1334 } else { 1335 return ERROR_CODE_COMMAND_DISALLOWED; 1336 } 1337 } 1338 1339 uint8_t att_server_request_to_send_indication(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1340 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1341 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1342 att_server_t * att_server = &hci_connection->att_server; 1343 att_connection_t * att_connection = &hci_connection->att_connection; 1344 bool added = btstack_linked_list_add_tail(&att_server->indication_requests, (btstack_linked_item_t*) callback_registration); 1345 att_server_request_can_send_now(att_server, att_connection); 1346 if (added){ 1347 return ERROR_CODE_SUCCESS; 1348 } else { 1349 return ERROR_CODE_COMMAND_DISALLOWED; 1350 } 1351 } 1352 1353 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){ 1354 1355 att_server_t * att_server = NULL; 1356 att_connection_t * att_connection = NULL; 1357 uint8_t * packet_buffer = NULL; 1358 1359 // prefer enhanced bearer 1360 #ifdef ENABLE_GATT_OVER_EATT 1361 att_server_eatt_bearer_t * eatt_bearer = att_server_eatt_bearer_for_con_handle(con_handle); 1362 if (eatt_bearer != NULL){ 1363 att_server = &eatt_bearer->att_server; 1364 att_connection = &eatt_bearer->att_connection; 1365 packet_buffer = eatt_bearer->send_buffer; 1366 } else 1367 #endif 1368 { 1369 hci_connection_t *hci_connection = hci_connection_for_handle(con_handle); 1370 if (hci_connection != NULL) { 1371 att_server = &hci_connection->att_server; 1372 att_connection = &hci_connection->att_connection; 1373 } 1374 } 1375 1376 if (att_server == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1377 if (!att_server_can_send_packet(att_server, att_connection)) return BTSTACK_ACL_BUFFERS_FULL; 1378 1379 if (packet_buffer == NULL){ 1380 l2cap_reserve_packet_buffer(); 1381 packet_buffer = l2cap_get_outgoing_buffer(); 1382 } 1383 1384 *out_att_connection = att_connection; 1385 *out_att_server = att_server; 1386 *out_packet_buffer = packet_buffer; 1387 return ERROR_CODE_SUCCESS; 1388 } 1389 1390 uint8_t att_server_notify(hci_con_handle_t con_handle, uint16_t attribute_handle, const uint8_t *value, uint16_t value_len){ 1391 att_server_t * att_server = NULL; 1392 att_connection_t * att_connection = NULL; 1393 uint8_t * packet_buffer = NULL; 1394 1395 uint8_t status = att_server_prepare_server_message(con_handle, &att_server, &att_connection, &packet_buffer); 1396 if (status != ERROR_CODE_SUCCESS){ 1397 return status; 1398 } 1399 1400 uint16_t size = att_prepare_handle_value_notification(att_connection, attribute_handle, value, value_len, packet_buffer); 1401 1402 return att_server_send_prepared(att_server, att_connection, NULL, size); 1403 } 1404 1405 /** 1406 * @brief notify client about multiple attribute value changes 1407 * @param con_handle 1408 * @param num_attributes 1409 * @param attribute_handles[] 1410 * @param values_data[] 1411 * @param values_len[] 1412 * @return 0 if ok, error otherwise 1413 */ 1414 uint8_t att_server_multiple_notify(hci_con_handle_t con_handle, uint8_t num_attributes, 1415 const uint16_t * attribute_handles, const uint8_t ** values_data, const uint16_t * values_len){ 1416 1417 att_server_t * att_server = NULL; 1418 att_connection_t * att_connection = NULL; 1419 uint8_t * packet_buffer = NULL; 1420 1421 uint8_t status = att_server_prepare_server_message(con_handle, &att_server, &att_connection, &packet_buffer); 1422 if (status != ERROR_CODE_SUCCESS){ 1423 return status; 1424 } 1425 1426 uint16_t size = att_prepare_handle_value_multiple_notification(att_connection, num_attributes, attribute_handles, values_data, values_len, packet_buffer); 1427 1428 return att_server_send_prepared(att_server, att_connection, packet_buffer, size); 1429 } 1430 1431 uint8_t att_server_indicate(hci_con_handle_t con_handle, uint16_t attribute_handle, const uint8_t *value, uint16_t value_len){ 1432 1433 att_server_t * att_server = NULL; 1434 att_connection_t * att_connection = NULL; 1435 uint8_t * packet_buffer = NULL; 1436 1437 uint8_t status = att_server_prepare_server_message(con_handle, &att_server, &att_connection, &packet_buffer); 1438 if (status != ERROR_CODE_SUCCESS){ 1439 return status; 1440 } 1441 1442 if (att_server->value_indication_handle != 0u) { 1443 // free reserved packet buffer 1444 if (att_server->bearer_type == ATT_BEARER_ENHANCED_LE){ 1445 l2cap_release_packet_buffer(); 1446 } 1447 return ATT_HANDLE_VALUE_INDICATION_IN_PROGRESS; 1448 } 1449 1450 // track indication 1451 att_server->value_indication_handle = attribute_handle; 1452 btstack_run_loop_set_timer_handler(&att_server->value_indication_timer, att_handle_value_indication_timeout); 1453 btstack_run_loop_set_timer(&att_server->value_indication_timer, ATT_TRANSACTION_TIMEOUT_MS); 1454 btstack_run_loop_add_timer(&att_server->value_indication_timer); 1455 1456 uint16_t size = att_prepare_handle_value_indication(att_connection, attribute_handle, value, value_len, packet_buffer); 1457 1458 return att_server_send_prepared(att_server, att_connection, NULL, size); 1459 } 1460 1461 uint16_t att_server_get_mtu(hci_con_handle_t con_handle){ 1462 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1463 if (!hci_connection) return 0; 1464 att_connection_t * att_connection = &hci_connection->att_connection; 1465 return att_connection->mtu; 1466 } 1467 1468 void att_server_deinit(void){ 1469 att_server_client_read_callback = NULL; 1470 att_server_client_write_callback = NULL; 1471 att_client_packet_handler = NULL; 1472 service_handlers = NULL; 1473 } 1474 1475 #ifdef ENABLE_GATT_OVER_EATT 1476 1477 #define MAX_NR_EATT_CHANNELS 5 1478 1479 static uint16_t att_server_eatt_receive_buffer_size; 1480 static uint16_t att_server_eatt_send_buffer_size; 1481 1482 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_cid(uint16_t cid){ 1483 btstack_linked_list_iterator_t it; 1484 btstack_linked_list_iterator_init(&it, &att_server_eatt_bearer_active); 1485 while(btstack_linked_list_iterator_has_next(&it)){ 1486 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) btstack_linked_list_iterator_next(&it); 1487 if (eatt_bearer->att_server.l2cap_cid == cid) { 1488 return eatt_bearer; 1489 } 1490 } 1491 return NULL; 1492 } 1493 1494 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_con_handle(hci_con_handle_t con_handle){ 1495 btstack_linked_list_iterator_t it; 1496 btstack_linked_list_iterator_init(&it, &att_server_eatt_bearer_active); 1497 while(btstack_linked_list_iterator_has_next(&it)){ 1498 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) btstack_linked_list_iterator_next(&it); 1499 if (eatt_bearer->att_connection.con_handle == con_handle) { 1500 return eatt_bearer; 1501 } 1502 } 1503 return NULL; 1504 } 1505 1506 static void att_server_eatt_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 1507 uint16_t cid; 1508 uint8_t status; 1509 uint16_t remote_mtu; 1510 1511 uint8_t i; 1512 uint8_t num_requested_bearers; 1513 uint8_t num_accepted_bearers; 1514 uint16_t initial_credits = L2CAP_LE_AUTOMATIC_CREDITS; 1515 uint8_t * receive_buffers[MAX_NR_EATT_CHANNELS]; 1516 uint16_t cids[MAX_NR_EATT_CHANNELS]; 1517 att_server_eatt_bearer_t * eatt_bearers[MAX_NR_EATT_CHANNELS]; 1518 att_server_eatt_bearer_t * eatt_bearer; 1519 att_server_t * att_server; 1520 att_connection_t * att_connection; 1521 1522 switch (packet_type) { 1523 1524 case L2CAP_DATA_PACKET: 1525 eatt_bearer = att_server_eatt_bearer_for_cid(channel); 1526 btstack_assert(eatt_bearer != NULL); 1527 att_server = &eatt_bearer->att_server; 1528 att_connection = &eatt_bearer->att_connection; 1529 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1530 break; 1531 1532 case HCI_EVENT_PACKET: 1533 switch (packet[0]) { 1534 1535 case L2CAP_EVENT_CAN_SEND_NOW: 1536 cid = l2cap_event_packet_sent_get_local_cid(packet); 1537 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1538 btstack_assert(eatt_bearer != NULL); 1539 att_server = &eatt_bearer->att_server; 1540 att_connection = &eatt_bearer->att_connection; 1541 // only used for EATT request responses 1542 btstack_assert(att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED); 1543 att_server_process_validated_request(att_server, att_connection, eatt_bearer->send_buffer); 1544 break; 1545 1546 case L2CAP_EVENT_PACKET_SENT: 1547 cid = l2cap_event_packet_sent_get_local_cid(packet); 1548 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1549 btstack_assert(eatt_bearer != NULL); 1550 att_server = &eatt_bearer->att_server; 1551 att_connection = &eatt_bearer->att_connection; 1552 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1553 break; 1554 1555 case L2CAP_EVENT_ECBM_INCOMING_CONNECTION: 1556 cid = l2cap_event_ecbm_incoming_connection_get_local_cid(packet); 1557 num_requested_bearers = l2cap_event_ecbm_incoming_connection_get_num_channels(packet); 1558 for (i = 0; i < num_requested_bearers; i++){ 1559 eatt_bearers[i] = (att_server_eatt_bearer_t *) btstack_linked_list_pop(&att_server_eatt_bearer_pool); 1560 if (eatt_bearers[i] == NULL) { 1561 break; 1562 } 1563 eatt_bearers[i]->att_connection.con_handle = l2cap_event_ecbm_incoming_connection_get_handle(packet); 1564 eatt_bearers[i]->att_server.bearer_type = ATT_BEARER_ENHANCED_LE; 1565 receive_buffers[i] = eatt_bearers[i]->receive_buffer; 1566 btstack_linked_list_add(&att_server_eatt_bearer_active, (btstack_linked_item_t *) eatt_bearers[i]); 1567 } 1568 num_accepted_bearers = i; 1569 status = l2cap_ecbm_accept_channels(cid, num_accepted_bearers, initial_credits, att_server_eatt_receive_buffer_size, receive_buffers, cids); 1570 btstack_assert(status == ERROR_CODE_SUCCESS); 1571 log_info("requested %u, accepted %u", num_requested_bearers, num_accepted_bearers); 1572 for (i=0;i<num_accepted_bearers;i++){ 1573 log_info("eatt l2cap cid: 0x%04x", cids[i]); 1574 eatt_bearers[i]->att_server.l2cap_cid = cids[i]; 1575 } 1576 break; 1577 1578 case L2CAP_EVENT_ECBM_CHANNEL_OPENED: 1579 cid = l2cap_event_ecbm_channel_opened_get_local_cid(packet); 1580 status = l2cap_event_ecbm_channel_opened_get_status(packet); 1581 remote_mtu = l2cap_event_ecbm_channel_opened_get_remote_mtu(packet); 1582 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1583 btstack_assert(eatt_bearer != NULL); 1584 eatt_bearer->att_connection.mtu_exchanged = true; 1585 eatt_bearer->att_connection.mtu = remote_mtu; 1586 eatt_bearer->att_connection.max_mtu = remote_mtu; 1587 log_info("L2CAP_EVENT_ECBM_CHANNEL_OPENED - cid 0x%04x mtu %u, status 0x%02x", cid, remote_mtu, status); 1588 break; 1589 1590 case L2CAP_EVENT_ECBM_RECONFIGURED: 1591 break; 1592 1593 case L2CAP_EVENT_CHANNEL_CLOSED: 1594 eatt_bearer = att_server_eatt_bearer_for_cid(l2cap_event_channel_closed_get_local_cid(packet)); 1595 btstack_assert(eatt_bearers != NULL); 1596 1597 // TODO: finalize - abort queued writes 1598 1599 btstack_linked_list_remove(&att_server_eatt_bearer_active, (btstack_linked_item_t *) eatt_bearer); 1600 btstack_linked_list_add(&att_server_eatt_bearer_pool, (btstack_linked_item_t *) eatt_bearer); 1601 break; 1602 default: 1603 break; 1604 } 1605 break; 1606 default: 1607 btstack_unreachable(); 1608 break; 1609 } 1610 } 1611 1612 // create eatt bearers 1613 uint8_t att_server_eatt_init(uint8_t num_eatt_bearers, uint8_t * storage_buffer, uint16_t storage_size){ 1614 uint16_t size_for_structs = num_eatt_bearers * sizeof(att_server_eatt_bearer_t); 1615 if (storage_size < size_for_structs) { 1616 return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED; 1617 } 1618 1619 // TODO: The minimum ATT_MTU for an Enhanced ATT bearer is 64 octets. 1620 1621 memset(storage_buffer, 0, storage_size); 1622 uint16_t buffer_size_per_bearer = ((storage_size - size_for_structs) / num_eatt_bearers); 1623 att_server_eatt_receive_buffer_size = buffer_size_per_bearer / 2; 1624 att_server_eatt_send_buffer_size = buffer_size_per_bearer / 2; 1625 uint8_t * bearer_buffer = &storage_buffer[size_for_structs]; 1626 uint8_t i; 1627 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) storage_buffer; 1628 log_info("%u EATT bearers with receive buffer size %u", 1629 num_eatt_bearers, att_server_eatt_receive_buffer_size); 1630 for (i=0;i<num_eatt_bearers;i++){ 1631 eatt_bearer->att_connection.con_handle = HCI_CON_HANDLE_INVALID; 1632 eatt_bearer->receive_buffer = bearer_buffer; 1633 bearer_buffer += att_server_eatt_receive_buffer_size; 1634 eatt_bearer->send_buffer = bearer_buffer; 1635 bearer_buffer += att_server_eatt_send_buffer_size; 1636 btstack_linked_list_add(&att_server_eatt_bearer_pool, (btstack_linked_item_t *) eatt_bearer); 1637 eatt_bearer++; 1638 } 1639 // TODO: define minimum EATT MTU 1640 l2cap_ecbm_register_service(att_server_eatt_handler, BLUETOOTH_PSM_EATT, 64, 0, false); 1641 1642 return 0; 1643 } 1644 #endif