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_server = &hci_connection->att_server; 466 att_server->ir_lookup_active = 0; 467 att_server->ir_le_device_db_index = sm_event_identity_resolving_succeeded_get_index(packet); 468 log_info("SM_EVENT_IDENTITY_RESOLVING_SUCCEEDED"); 469 att_run_for_context(att_server, att_connection); 470 break; 471 case SM_EVENT_IDENTITY_RESOLVING_FAILED: 472 con_handle = sm_event_identity_resolving_failed_get_handle(packet); 473 hci_connection = hci_connection_for_handle(con_handle); 474 if (!hci_connection) break; 475 att_server = &hci_connection->att_server; 476 log_info("SM_EVENT_IDENTITY_RESOLVING_FAILED"); 477 att_server->ir_lookup_active = 0; 478 att_server->ir_le_device_db_index = -1; 479 att_run_for_context(att_server, att_connection); 480 break; 481 482 // Pairing started - delete stored CCC values 483 // - assumes pairing indicates either new device or re-pairing, in both cases there should be no stored CCC values 484 // - assumes that all events have the con handle as the first field 485 case SM_EVENT_JUST_WORKS_REQUEST: 486 case SM_EVENT_PASSKEY_DISPLAY_NUMBER: 487 case SM_EVENT_PASSKEY_INPUT_NUMBER: 488 case SM_EVENT_NUMERIC_COMPARISON_REQUEST: 489 con_handle = sm_event_just_works_request_get_handle(packet); 490 hci_connection = hci_connection_for_handle(con_handle); 491 if (!hci_connection) break; 492 att_server = &hci_connection->att_server; 493 att_server->pairing_active = 1; 494 log_info("SM Pairing started"); 495 if (att_server->ir_le_device_db_index < 0) break; 496 att_run_for_context(att_server, att_connection); 497 // index not valid anymore 498 att_server->ir_le_device_db_index = -1; 499 break; 500 501 // Bonding completed 502 case SM_EVENT_IDENTITY_CREATED: 503 con_handle = sm_event_identity_created_get_handle(packet); 504 hci_connection = hci_connection_for_handle(con_handle); 505 if (!hci_connection) return; 506 att_server = &hci_connection->att_server; 507 att_server->pairing_active = 0; 508 att_server->ir_le_device_db_index = sm_event_identity_created_get_index(packet); 509 att_run_for_context(att_server, att_connection); 510 break; 511 512 // Pairing complete (with/without bonding=storing of pairing information) 513 case SM_EVENT_PAIRING_COMPLETE: 514 con_handle = sm_event_pairing_complete_get_handle(packet); 515 hci_connection = hci_connection_for_handle(con_handle); 516 if (!hci_connection) return; 517 att_server = &hci_connection->att_server; 518 att_server->pairing_active = 0; 519 att_run_for_context(att_server, att_connection); 520 break; 521 522 // Authorization 523 case SM_EVENT_AUTHORIZATION_RESULT: { 524 con_handle = sm_event_authorization_result_get_handle(packet); 525 hci_connection = hci_connection_for_handle(con_handle); 526 if (!hci_connection) break; 527 att_server = &hci_connection->att_server; 528 att_connection = &hci_connection->att_connection; 529 att_connection->authorized = sm_event_authorization_result_get_authorization_result(packet); 530 att_server_request_can_send_now(att_server, att_connection); 531 break; 532 } 533 default: 534 break; 535 } 536 break; 537 #ifdef ENABLE_GATT_OVER_CLASSIC 538 case L2CAP_DATA_PACKET: 539 hci_connections_get_iterator(&it); 540 while(btstack_linked_list_iterator_has_next(&it)){ 541 hci_connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 542 att_server = &hci_connection->att_server; 543 att_connection = &hci_connection->att_connection; 544 if (att_server->l2cap_cid == channel) { 545 att_server_handle_att_pdu(att_server, att_connection, packet, size); 546 break; 547 } 548 } 549 break; 550 #endif 551 552 default: 553 break; 554 } 555 } 556 557 static uint8_t 558 att_server_send_prepared(const att_server_t *att_server, const att_connection_t *att_connection, uint8_t *buffer, 559 uint16_t size) { 560 uint8_t status = ERROR_CODE_SUCCESS; 561 switch (att_server->bearer_type) { 562 case ATT_BEARER_UNENHANCED_LE: 563 status = l2cap_send_prepared_connectionless(att_connection->con_handle, L2CAP_CID_ATTRIBUTE_PROTOCOL, size); 564 break; 565 #ifdef ENABLE_GATT_OVER_CLASSIC 566 case ATT_BEARER_UNENHANCED_CLASSIC: 567 status = l2cap_send_prepared(att_server->l2cap_cid, size); 568 break; 569 #endif 570 #ifdef ENABLE_GATT_OVER_EATT 571 case ATT_BEARER_ENHANCED_LE: 572 btstack_assert(buffer != NULL); 573 status = l2cap_send(att_server->l2cap_cid, buffer, size); 574 break; 575 #endif 576 default: 577 btstack_unreachable(); 578 break; 579 } 580 return status; 581 } 582 583 #ifdef ENABLE_LE_SIGNED_WRITE 584 static void att_signed_write_handle_cmac_result(uint8_t hash[8]){ 585 att_server_t * att_server = NULL; 586 att_connection_t * att_connection = NULL; 587 bool found = att_server_connections_for_state(ATT_SERVER_W4_SIGNED_WRITE_VALIDATION, &att_server, &att_connection); 588 589 if (found == false){ 590 return; 591 } 592 593 uint8_t hash_flipped[8]; 594 reverse_64(hash, hash_flipped); 595 if (memcmp(hash_flipped, &att_server->request_buffer[att_server->request_size-8], 8) != 0){ 596 log_info("ATT Signed Write, invalid signature"); 597 #ifdef ENABLE_TESTING_SUPPORT 598 printf("ATT Signed Write, invalid signature\n"); 599 #endif 600 att_server->state = ATT_SERVER_IDLE; 601 return; 602 } 603 log_info("ATT Signed Write, valid signature"); 604 #ifdef ENABLE_TESTING_SUPPORT 605 printf("ATT Signed Write, valid signature\n"); 606 #endif 607 608 // update sequence number 609 uint32_t counter_packet = little_endian_read_32(att_server->request_buffer, att_server->request_size-12); 610 le_device_db_remote_counter_set(att_server->ir_le_device_db_index, counter_packet+1); 611 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 612 att_server_request_can_send_now(att_server, att_connection); 613 } 614 #endif 615 616 // pre: att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED 617 // pre: can send now 618 // uses l2cap outgoing buffer if no eatt_buffer provided 619 // returns: 1 if packet was sent 620 static int 621 att_server_process_validated_request(att_server_t *att_server, att_connection_t *att_connection, uint8_t *eatt_buffer) { 622 623 uint8_t * att_response_buffer; 624 if (eatt_buffer != NULL){ 625 att_response_buffer = eatt_buffer; 626 } else { 627 l2cap_reserve_packet_buffer(); 628 att_response_buffer = l2cap_get_outgoing_buffer(); 629 } 630 631 uint16_t att_response_size = 0; 632 // Send Error Response for MTU Request over connection-oriented channel 633 if ((att_server->bearer_type != ATT_BEARER_UNENHANCED_LE) && (att_server->request_buffer[0] == ATT_EXCHANGE_MTU_REQUEST)){ 634 att_response_size = 5; 635 att_response_buffer[0] = ATT_ERROR_RESPONSE; 636 att_response_buffer[1] = ATT_EXCHANGE_MTU_REQUEST; 637 att_response_buffer[2] = 0; 638 att_response_buffer[3] = 0; 639 att_response_buffer[4] = ATT_ERROR_REQUEST_NOT_SUPPORTED; 640 } else { 641 att_response_size = att_handle_request(att_connection, att_server->request_buffer, att_server->request_size, att_response_buffer); 642 } 643 644 #ifdef ENABLE_ATT_DELAYED_RESPONSE 645 if ((att_response_size == ATT_READ_RESPONSE_PENDING) || (att_response_size == ATT_INTERNAL_WRITE_RESPONSE_PENDING)){ 646 // update state 647 att_server->state = ATT_SERVER_RESPONSE_PENDING; 648 649 // callback with handle ATT_READ_RESPONSE_PENDING for reads 650 if (att_response_size == ATT_READ_RESPONSE_PENDING){ 651 att_server_client_read_callback(att_connection->con_handle, ATT_READ_RESPONSE_PENDING, 0, NULL, 0); 652 } 653 654 // free reserved buffer 655 if (eatt_buffer == NULL){ 656 l2cap_release_packet_buffer(); 657 } 658 return 0; 659 } 660 #endif 661 662 // intercept "insufficient authorization" for authenticated connections to allow for user authorization 663 if ((att_response_size >= 4u) 664 && (att_response_buffer[0] == ATT_ERROR_RESPONSE) 665 && (att_response_buffer[4] == ATT_ERROR_INSUFFICIENT_AUTHORIZATION) 666 && (att_connection->authenticated != 0u)){ 667 668 switch (gap_authorization_state(att_connection->con_handle)){ 669 case AUTHORIZATION_UNKNOWN: 670 if (eatt_buffer == NULL){ 671 l2cap_release_packet_buffer(); 672 } 673 sm_request_pairing(att_connection->con_handle); 674 return 0; 675 case AUTHORIZATION_PENDING: 676 if (eatt_buffer == NULL){ 677 l2cap_release_packet_buffer(); 678 } 679 return 0; 680 default: 681 break; 682 } 683 } 684 685 att_server->state = ATT_SERVER_IDLE; 686 if (att_response_size == 0u) { 687 if (eatt_buffer == NULL){ 688 l2cap_release_packet_buffer(); 689 } 690 return 0; 691 } 692 693 (void) att_server_send_prepared(att_server, att_connection, eatt_buffer, att_response_size); 694 695 // notify client about MTU exchange result 696 if (att_response_buffer[0] == ATT_EXCHANGE_MTU_RESPONSE){ 697 att_emit_mtu_event(att_connection->con_handle, att_connection->mtu); 698 } 699 return 1; 700 } 701 702 #ifdef ENABLE_ATT_DELAYED_RESPONSE 703 uint8_t att_server_response_ready(hci_con_handle_t con_handle){ 704 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 705 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 706 att_server_t * att_server = &hci_connection->att_server; 707 att_connection_t * att_connection = &hci_connection->att_connection; 708 if (att_server->state != ATT_SERVER_RESPONSE_PENDING) return ERROR_CODE_COMMAND_DISALLOWED; 709 710 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 711 att_server_request_can_send_now(att_server, att_connection); 712 return ERROR_CODE_SUCCESS; 713 } 714 #endif 715 716 static void att_run_for_context(att_server_t * att_server, att_connection_t * att_connection){ 717 switch (att_server->state){ 718 case ATT_SERVER_REQUEST_RECEIVED: 719 switch (att_server->bearer_type){ 720 case ATT_BEARER_UNENHANCED_LE: 721 // wait until re-encryption as central is complete 722 if (gap_reconnect_security_setup_active(att_connection->con_handle)) { 723 return; 724 }; 725 break; 726 #if defined(ENABLE_GATT_OVER_CLASSIC) || defined (ENABLE_GATT_OVER_EATT) 727 #ifdef ENABLE_GATT_OVER_CLASSIC 728 case ATT_BEARER_UNENHANCED_CLASSIC: 729 /* fall through */ 730 #endif 731 #ifdef ENABLE_GATT_OVER_EATT 732 case ATT_BEARER_ENHANCED_LE: 733 #endif 734 // ok 735 break; 736 #endif 737 default: 738 btstack_unreachable(); 739 break; 740 } 741 742 // wait until pairing is complete 743 if (att_server->pairing_active) break; 744 745 #ifdef ENABLE_LE_SIGNED_WRITE 746 if (att_server->request_buffer[0] == ATT_SIGNED_WRITE_COMMAND){ 747 log_info("ATT Signed Write!"); 748 if (!sm_cmac_ready()) { 749 log_info("ATT Signed Write, sm_cmac engine not ready. Abort"); 750 att_server->state = ATT_SERVER_IDLE; 751 return; 752 } 753 if (att_server->request_size < (3 + 12)) { 754 log_info("ATT Signed Write, request to short. Abort."); 755 att_server->state = ATT_SERVER_IDLE; 756 return; 757 } 758 if (att_server->ir_lookup_active){ 759 return; 760 } 761 if (att_server->ir_le_device_db_index < 0){ 762 log_info("ATT Signed Write, CSRK not available"); 763 att_server->state = ATT_SERVER_IDLE; 764 return; 765 } 766 767 // check counter 768 uint32_t counter_packet = little_endian_read_32(att_server->request_buffer, att_server->request_size-12); 769 uint32_t counter_db = le_device_db_remote_counter_get(att_server->ir_le_device_db_index); 770 log_info("ATT Signed Write, DB counter %"PRIu32", packet counter %"PRIu32, counter_db, counter_packet); 771 if (counter_packet < counter_db){ 772 log_info("ATT Signed Write, db reports higher counter, abort"); 773 att_server->state = ATT_SERVER_IDLE; 774 return; 775 } 776 777 // signature is { sequence counter, secure hash } 778 sm_key_t csrk; 779 le_device_db_remote_csrk_get(att_server->ir_le_device_db_index, csrk); 780 att_server->state = ATT_SERVER_W4_SIGNED_WRITE_VALIDATION; 781 log_info("Orig Signature: "); 782 log_info_hexdump( &att_server->request_buffer[att_server->request_size-8], 8); 783 uint16_t attribute_handle = little_endian_read_16(att_server->request_buffer, 1); 784 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); 785 return; 786 } 787 #endif 788 // move on 789 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 790 att_server_request_can_send_now(att_server, att_connection); 791 break; 792 793 default: 794 break; 795 } 796 } 797 798 static bool att_server_data_ready_for_phase(att_server_t * att_server, att_server_run_phase_t phase){ 799 switch (phase){ 800 case ATT_SERVER_RUN_PHASE_1_REQUESTS: 801 return att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 802 case ATT_SERVER_RUN_PHASE_2_INDICATIONS: 803 return (!btstack_linked_list_empty(&att_server->indication_requests) && (att_server->value_indication_handle == 0u)); 804 case ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS: 805 return (!btstack_linked_list_empty(&att_server->notification_requests)); 806 default: 807 btstack_assert(false); 808 return false; 809 } 810 } 811 812 static void att_server_trigger_send_for_phase(att_server_t * att_server, att_connection_t * att_connection, att_server_run_phase_t phase){ 813 btstack_context_callback_registration_t * client; 814 switch (phase){ 815 case ATT_SERVER_RUN_PHASE_1_REQUESTS: 816 att_server_process_validated_request(att_server, att_connection, NULL); 817 break; 818 case ATT_SERVER_RUN_PHASE_2_INDICATIONS: 819 client = (btstack_context_callback_registration_t*) att_server->indication_requests; 820 btstack_linked_list_remove(&att_server->indication_requests, (btstack_linked_item_t *) client); 821 client->callback(client->context); 822 break; 823 case ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS: 824 client = (btstack_context_callback_registration_t*) att_server->notification_requests; 825 btstack_linked_list_remove(&att_server->notification_requests, (btstack_linked_item_t *) client); 826 client->callback(client->context); 827 break; 828 default: 829 btstack_assert(false); 830 break; 831 } 832 } 833 834 static void att_server_handle_can_send_now(void){ 835 836 hci_con_handle_t last_send_con_handle = HCI_CON_HANDLE_INVALID; 837 hci_connection_t * request_hci_connection = NULL; 838 bool can_send_now = true; 839 uint8_t phase_index; 840 841 for (phase_index = ATT_SERVER_RUN_PHASE_1_REQUESTS; phase_index <= ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS; phase_index++){ 842 att_server_run_phase_t phase = (att_server_run_phase_t) phase_index; 843 hci_con_handle_t skip_connections_until = att_server_last_can_send_now; 844 while (true){ 845 btstack_linked_list_iterator_t it; 846 hci_connections_get_iterator(&it); 847 while(btstack_linked_list_iterator_has_next(&it)){ 848 hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 849 att_server_t * att_server = &connection->att_server; 850 att_connection_t * att_connection = &connection->att_connection; 851 852 bool data_ready = att_server_data_ready_for_phase(att_server, phase); 853 854 // log_debug("phase %u, handle 0x%04x, skip until 0x%04x, data ready %u", phase, att_connection->con_handle, skip_connections_until, data_ready); 855 856 // skip until last sender found (which is also skipped) 857 if (skip_connections_until != HCI_CON_HANDLE_INVALID){ 858 if (data_ready && (request_hci_connection == NULL)){ 859 request_hci_connection = connection; 860 } 861 if (skip_connections_until == att_connection->con_handle){ 862 skip_connections_until = HCI_CON_HANDLE_INVALID; 863 } 864 continue; 865 }; 866 867 if (data_ready){ 868 if (can_send_now){ 869 att_server_trigger_send_for_phase(att_server, att_connection, phase); 870 last_send_con_handle = att_connection->con_handle; 871 can_send_now = att_server_can_send_packet(att_server, att_connection); 872 data_ready = att_server_data_ready_for_phase(att_server, phase); 873 if (data_ready && (request_hci_connection == NULL)){ 874 request_hci_connection = connection; 875 } 876 } else { 877 request_hci_connection = connection; 878 break; 879 } 880 } 881 } 882 883 // stop skipping (handles disconnect by last send connection) 884 skip_connections_until = HCI_CON_HANDLE_INVALID; 885 886 // Exit loop, if we cannot send 887 if (!can_send_now) break; 888 889 // Exit loop, if we can send but there are also no further request 890 if (request_hci_connection == NULL) break; 891 892 // Finally, if we still can send and there are requests, just try again 893 request_hci_connection = NULL; 894 } 895 // update last send con handle for round robin 896 if (last_send_con_handle != HCI_CON_HANDLE_INVALID){ 897 att_server_last_can_send_now = last_send_con_handle; 898 } 899 } 900 901 if (request_hci_connection == NULL) return; 902 903 att_server_t * att_server = &request_hci_connection->att_server; 904 att_connection_t * att_connection = &request_hci_connection->att_connection; 905 att_server_request_can_send_now(att_server, att_connection); 906 } 907 908 static void att_server_handle_att_pdu(att_server_t * att_server, att_connection_t * att_connection, uint8_t * packet, uint16_t size){ 909 910 uint8_t opcode = packet[0u]; 911 uint8_t method = opcode & 0x03fu; 912 bool invalid = method > ATT_MULTIPLE_HANDLE_VALUE_NTF; 913 bool command = (opcode & 0x40u) != 0u; 914 915 // ignore invalid commands 916 if (invalid && command){ 917 return; 918 } 919 920 // handle value indication confirms 921 if ((opcode == ATT_HANDLE_VALUE_CONFIRMATION) && (att_server->value_indication_handle != 0u)){ 922 btstack_run_loop_remove_timer(&att_server->value_indication_timer); 923 uint16_t att_handle = att_server->value_indication_handle; 924 att_server->value_indication_handle = 0u; 925 att_handle_value_indication_notify_client(0u, att_connection->con_handle, att_handle); 926 att_server_request_can_send_now(att_server, att_connection); 927 return; 928 } 929 930 // directly process command 931 // note: signed write cannot be handled directly as authentication needs to be verified 932 if (opcode == ATT_WRITE_COMMAND){ 933 att_handle_request(att_connection, packet, size, NULL); 934 return; 935 } 936 937 // check size 938 if (size > sizeof(att_server->request_buffer)) { 939 log_info("drop att pdu 0x%02x as size %u > att_server->request_buffer %u", packet[0], size, (int) sizeof(att_server->request_buffer)); 940 return; 941 } 942 943 #ifdef ENABLE_LE_SIGNED_WRITE 944 // abort signed write validation if a new request comes in (but finish previous signed write if possible) 945 if (att_server->state == ATT_SERVER_W4_SIGNED_WRITE_VALIDATION){ 946 if (packet[0] == ATT_SIGNED_WRITE_COMMAND){ 947 log_info("skip new signed write request as previous is in validation"); 948 return; 949 } else { 950 log_info("abort signed write validation to process new request"); 951 att_server->state = ATT_SERVER_IDLE; 952 } 953 } 954 #endif 955 // last request still in processing? 956 if (att_server->state != ATT_SERVER_IDLE){ 957 log_info("skip att pdu 0x%02x as server not idle (state %u)", packet[0], att_server->state); 958 return; 959 } 960 961 // store request 962 att_server->state = ATT_SERVER_REQUEST_RECEIVED; 963 att_server->request_size = size; 964 (void)memcpy(att_server->request_buffer, packet, size); 965 966 att_run_for_context(att_server, att_connection); 967 } 968 969 static void att_packet_handler(uint8_t packet_type, uint16_t handle, uint8_t *packet, uint16_t size){ 970 hci_connection_t * hci_connection; 971 att_connection_t * att_connection; 972 att_server_t * att_server; 973 974 switch (packet_type){ 975 case HCI_EVENT_PACKET: 976 switch (packet[0]){ 977 case L2CAP_EVENT_CAN_SEND_NOW: 978 att_server_handle_can_send_now(); 979 break; 980 case ATT_EVENT_MTU_EXCHANGE_COMPLETE: 981 // GATT client has negotiated the mtu for this connection 982 hci_connection = hci_connection_for_handle(handle); 983 if (!hci_connection) break; 984 att_connection = &hci_connection->att_connection; 985 att_connection->mtu = little_endian_read_16(packet, 4); 986 break; 987 default: 988 break; 989 } 990 break; 991 992 case ATT_DATA_PACKET: 993 log_debug("ATT Packet, handle 0x%04x", handle); 994 hci_connection = hci_connection_for_handle(handle); 995 if (!hci_connection) break; 996 997 att_server = &hci_connection->att_server; 998 att_connection = &hci_connection->att_connection; 999 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1000 break; 1001 1002 default: 1003 break; 1004 } 1005 } 1006 1007 // --------------------- 1008 // persistent CCC writes 1009 static uint32_t att_server_persistent_ccc_tag_for_index(uint8_t index){ 1010 return ('B' << 24u) | ('T' << 16u) | ('C' << 8u) | index; 1011 } 1012 1013 static void att_server_persistent_ccc_write(hci_con_handle_t con_handle, uint16_t att_handle, uint16_t value){ 1014 // lookup att_server instance 1015 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1016 if (!hci_connection) return; 1017 att_server_t * att_server = &hci_connection->att_server; 1018 int le_device_index = att_server->ir_le_device_db_index; 1019 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); 1020 1021 // check if bonded 1022 if (le_device_index < 0) return; 1023 1024 // get btstack_tlv 1025 const btstack_tlv_t * tlv_impl = NULL; 1026 void * tlv_context; 1027 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1028 if (!tlv_impl) return; 1029 1030 // update ccc tag 1031 int index; 1032 uint32_t highest_seq_nr = 0; 1033 uint32_t lowest_seq_nr = 0; 1034 uint32_t tag_for_lowest_seq_nr = 0; 1035 uint32_t tag_for_empty = 0; 1036 persistent_ccc_entry_t entry; 1037 for (index=0; index<NVN_NUM_GATT_SERVER_CCC; index++){ 1038 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1039 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1040 1041 // empty/invalid tag 1042 if (len != sizeof(persistent_ccc_entry_t)){ 1043 tag_for_empty = tag; 1044 continue; 1045 } 1046 // update highest seq nr 1047 if (entry.seq_nr > highest_seq_nr){ 1048 highest_seq_nr = entry.seq_nr; 1049 } 1050 // find entry with lowest seq nr 1051 if ((tag_for_lowest_seq_nr == 0u) || (entry.seq_nr < lowest_seq_nr)){ 1052 tag_for_lowest_seq_nr = tag; 1053 lowest_seq_nr = entry.seq_nr; 1054 } 1055 1056 if (entry.device_index != le_device_index) continue; 1057 if (entry.att_handle != att_handle) continue; 1058 1059 // found matching entry 1060 if (value != 0){ 1061 // update 1062 if (entry.value == value) { 1063 log_info("CCC Index %u: Up-to-date", index); 1064 return; 1065 } 1066 entry.value = (uint8_t) value; 1067 entry.seq_nr = highest_seq_nr + 1u; 1068 log_info("CCC Index %u: Store", index); 1069 int result = tlv_impl->store_tag(tlv_context, tag, (const uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1070 if (result != 0){ 1071 log_error("Store tag index %u failed", index); 1072 } 1073 } else { 1074 // delete 1075 log_info("CCC Index %u: Delete", index); 1076 tlv_impl->delete_tag(tlv_context, tag); 1077 } 1078 return; 1079 } 1080 1081 log_info("tag_for_empty %"PRIx32", tag_for_lowest_seq_nr %"PRIx32, tag_for_empty, tag_for_lowest_seq_nr); 1082 1083 if (value == 0u){ 1084 // done 1085 return; 1086 } 1087 1088 uint32_t tag_to_use = 0u; 1089 if (tag_for_empty != 0u){ 1090 tag_to_use = tag_for_empty; 1091 } else if (tag_for_lowest_seq_nr){ 1092 tag_to_use = tag_for_lowest_seq_nr; 1093 } else { 1094 // should not happen 1095 return; 1096 } 1097 // store ccc tag 1098 entry.seq_nr = highest_seq_nr + 1u; 1099 entry.device_index = le_device_index; 1100 entry.att_handle = att_handle; 1101 entry.value = (uint8_t) value; 1102 int result = tlv_impl->store_tag(tlv_context, tag_to_use, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1103 if (result != 0){ 1104 log_error("Store tag index %u failed", index); 1105 } 1106 } 1107 1108 static void att_server_persistent_ccc_clear(att_server_t * att_server){ 1109 int le_device_index = att_server->ir_le_device_db_index; 1110 log_info("Clear CCC values of remote %s, le device id %d", bd_addr_to_str(att_server->peer_address), le_device_index); 1111 // check if bonded 1112 if (le_device_index < 0) return; 1113 // get btstack_tlv 1114 const btstack_tlv_t * tlv_impl = NULL; 1115 void * tlv_context; 1116 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1117 if (!tlv_impl) return; 1118 // get all ccc tag 1119 int index; 1120 persistent_ccc_entry_t entry; 1121 for (index=0;index<NVN_NUM_GATT_SERVER_CCC;index++){ 1122 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1123 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1124 if (len != sizeof(persistent_ccc_entry_t)) continue; 1125 if (entry.device_index != le_device_index) continue; 1126 // delete entry 1127 log_info("CCC Index %u: Delete", index); 1128 tlv_impl->delete_tag(tlv_context, tag); 1129 } 1130 } 1131 1132 static void att_server_persistent_ccc_restore(att_server_t * att_server, att_connection_t * att_connection){ 1133 int le_device_index = att_server->ir_le_device_db_index; 1134 log_info("Restore CCC values of remote %s, le device id %d", bd_addr_to_str(att_server->peer_address), le_device_index); 1135 // check if bonded 1136 if (le_device_index < 0) return; 1137 // get btstack_tlv 1138 const btstack_tlv_t * tlv_impl = NULL; 1139 void * tlv_context; 1140 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1141 if (!tlv_impl) return; 1142 // get all ccc tag 1143 int index; 1144 persistent_ccc_entry_t entry; 1145 for (index=0;index<NVN_NUM_GATT_SERVER_CCC;index++){ 1146 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1147 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1148 if (len != sizeof(persistent_ccc_entry_t)) continue; 1149 if (entry.device_index != le_device_index) continue; 1150 // simulate write callback 1151 uint16_t attribute_handle = entry.att_handle; 1152 uint8_t value[2]; 1153 little_endian_store_16(value, 0, entry.value); 1154 att_write_callback_t callback = att_server_write_callback_for_handle(attribute_handle); 1155 if (!callback) continue; 1156 log_info("CCC Index %u: Set Attribute handle 0x%04x to value 0x%04x", index, attribute_handle, entry.value ); 1157 (*callback)(att_connection->con_handle, attribute_handle, ATT_TRANSACTION_MODE_NONE, 0, value, sizeof(value)); 1158 } 1159 } 1160 1161 // persistent CCC writes 1162 // --------------------- 1163 1164 // gatt service management 1165 static att_service_handler_t * att_service_handler_for_handle(uint16_t handle){ 1166 btstack_linked_list_iterator_t it; 1167 btstack_linked_list_iterator_init(&it, &service_handlers); 1168 while (btstack_linked_list_iterator_has_next(&it)){ 1169 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1170 if (handler->start_handle > handle) continue; 1171 if (handler->end_handle < handle) continue; 1172 return handler; 1173 } 1174 return NULL; 1175 } 1176 static att_read_callback_t att_server_read_callback_for_handle(uint16_t handle){ 1177 att_service_handler_t * handler = att_service_handler_for_handle(handle); 1178 if (handler != NULL) return handler->read_callback; 1179 return att_server_client_read_callback; 1180 } 1181 1182 static att_write_callback_t att_server_write_callback_for_handle(uint16_t handle){ 1183 att_service_handler_t * handler = att_service_handler_for_handle(handle); 1184 if (handler != NULL) return handler->write_callback; 1185 return att_server_client_write_callback; 1186 } 1187 1188 static btstack_packet_handler_t att_server_packet_handler_for_handle(uint16_t handle){ 1189 att_service_handler_t * handler = att_service_handler_for_handle(handle); 1190 if (handler != NULL) return handler->packet_handler; 1191 return att_client_packet_handler; 1192 } 1193 1194 static void att_notify_write_callbacks(hci_con_handle_t con_handle, uint16_t transaction_mode){ 1195 // notify all callbacks 1196 btstack_linked_list_iterator_t it; 1197 btstack_linked_list_iterator_init(&it, &service_handlers); 1198 while (btstack_linked_list_iterator_has_next(&it)){ 1199 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1200 if (!handler->write_callback) continue; 1201 (*handler->write_callback)(con_handle, 0, transaction_mode, 0, NULL, 0); 1202 } 1203 if (!att_server_client_write_callback) return; 1204 (*att_server_client_write_callback)(con_handle, 0, transaction_mode, 0, NULL, 0); 1205 } 1206 1207 // returns first reported error or 0 1208 static uint8_t att_validate_prepared_write(hci_con_handle_t con_handle){ 1209 btstack_linked_list_iterator_t it; 1210 btstack_linked_list_iterator_init(&it, &service_handlers); 1211 while (btstack_linked_list_iterator_has_next(&it)){ 1212 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1213 if (!handler->write_callback) continue; 1214 uint8_t error_code = (*handler->write_callback)(con_handle, 0, ATT_TRANSACTION_MODE_VALIDATE, 0, NULL, 0); 1215 if (error_code != 0u) return error_code; 1216 } 1217 if (!att_server_client_write_callback) return 0; 1218 return (*att_server_client_write_callback)(con_handle, 0, ATT_TRANSACTION_MODE_VALIDATE, 0, NULL, 0); 1219 } 1220 1221 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){ 1222 att_read_callback_t callback = att_server_read_callback_for_handle(attribute_handle); 1223 if (!callback) return 0; 1224 return (*callback)(con_handle, attribute_handle, offset, buffer, buffer_size); 1225 } 1226 1227 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){ 1228 switch (transaction_mode){ 1229 case ATT_TRANSACTION_MODE_VALIDATE: 1230 return att_validate_prepared_write(con_handle); 1231 case ATT_TRANSACTION_MODE_EXECUTE: 1232 case ATT_TRANSACTION_MODE_CANCEL: 1233 att_notify_write_callbacks(con_handle, transaction_mode); 1234 return 0; 1235 default: 1236 break; 1237 } 1238 1239 // track CCC writes 1240 if (att_is_persistent_ccc(attribute_handle) && (offset == 0u) && (buffer_size == 2u)){ 1241 att_server_persistent_ccc_write(con_handle, attribute_handle, little_endian_read_16(buffer, 0)); 1242 } 1243 1244 att_write_callback_t callback = att_server_write_callback_for_handle(attribute_handle); 1245 if (!callback) return 0; 1246 return (*callback)(con_handle, attribute_handle, transaction_mode, offset, buffer, buffer_size); 1247 } 1248 1249 /** 1250 * @brief register read/write callbacks for specific handle range 1251 * @param att_service_handler_t 1252 */ 1253 void att_server_register_service_handler(att_service_handler_t * handler){ 1254 bool att_server_registered = false; 1255 if (att_service_handler_for_handle(handler->start_handle)){ 1256 att_server_registered = true; 1257 } 1258 1259 if (att_service_handler_for_handle(handler->end_handle)){ 1260 att_server_registered = true; 1261 } 1262 1263 if (att_server_registered){ 1264 log_error("handler for range 0x%04x-0x%04x already registered", handler->start_handle, handler->end_handle); 1265 return; 1266 } 1267 btstack_linked_list_add(&service_handlers, (btstack_linked_item_t*) handler); 1268 } 1269 1270 void att_server_init(uint8_t const * db, att_read_callback_t read_callback, att_write_callback_t write_callback){ 1271 1272 // store callbacks 1273 att_server_client_read_callback = read_callback; 1274 att_server_client_write_callback = write_callback; 1275 1276 // register for HCI Events 1277 hci_event_callback_registration.callback = &att_event_packet_handler; 1278 hci_add_event_handler(&hci_event_callback_registration); 1279 1280 // register for SM events 1281 sm_event_callback_registration.callback = &att_event_packet_handler; 1282 sm_add_event_handler(&sm_event_callback_registration); 1283 1284 // and L2CAP ATT Server PDUs 1285 att_dispatch_register_server(att_packet_handler); 1286 1287 #ifdef ENABLE_GATT_OVER_CLASSIC 1288 // setup l2cap service 1289 l2cap_register_service(&att_event_packet_handler, PSM_ATT, 0xffff, gap_get_security_level()); 1290 #endif 1291 1292 att_set_db(db); 1293 att_set_read_callback(att_server_read_callback); 1294 att_set_write_callback(att_server_write_callback); 1295 } 1296 1297 void att_server_register_packet_handler(btstack_packet_handler_t handler){ 1298 att_client_packet_handler = handler; 1299 } 1300 1301 1302 // to be deprecated 1303 int att_server_can_send_packet_now(hci_con_handle_t con_handle){ 1304 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1305 if (!hci_connection) return 0; 1306 att_server_t * att_server = &hci_connection->att_server; 1307 att_connection_t * att_connection = &hci_connection->att_connection; 1308 return att_server_can_send_packet(att_server, att_connection); 1309 } 1310 1311 uint8_t att_server_register_can_send_now_callback(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1312 return att_server_request_to_send_notification(callback_registration, con_handle); 1313 } 1314 1315 void att_server_request_can_send_now_event(hci_con_handle_t con_handle){ 1316 att_client_waiting_for_can_send_registration.callback = &att_emit_can_send_now_event; 1317 att_server_request_to_send_notification(&att_client_waiting_for_can_send_registration, con_handle); 1318 } 1319 // end of deprecated 1320 1321 uint8_t att_server_request_to_send_notification(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1322 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1323 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1324 att_server_t * att_server = &hci_connection->att_server; 1325 att_connection_t * att_connection = &hci_connection->att_connection; 1326 bool added = btstack_linked_list_add_tail(&att_server->notification_requests, (btstack_linked_item_t*) callback_registration); 1327 att_server_request_can_send_now(att_server, att_connection); 1328 if (added){ 1329 return ERROR_CODE_SUCCESS; 1330 } else { 1331 return ERROR_CODE_COMMAND_DISALLOWED; 1332 } 1333 } 1334 1335 uint8_t att_server_request_to_send_indication(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1336 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1337 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1338 att_server_t * att_server = &hci_connection->att_server; 1339 att_connection_t * att_connection = &hci_connection->att_connection; 1340 bool added = btstack_linked_list_add_tail(&att_server->indication_requests, (btstack_linked_item_t*) callback_registration); 1341 att_server_request_can_send_now(att_server, att_connection); 1342 if (added){ 1343 return ERROR_CODE_SUCCESS; 1344 } else { 1345 return ERROR_CODE_COMMAND_DISALLOWED; 1346 } 1347 } 1348 1349 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){ 1350 1351 att_server_t * att_server = NULL; 1352 att_connection_t * att_connection = NULL; 1353 uint8_t * packet_buffer = NULL; 1354 1355 // prefer enhanced bearer 1356 #ifdef ENABLE_GATT_OVER_EATT 1357 att_server_eatt_bearer_t * eatt_bearer = att_server_eatt_bearer_for_con_handle(con_handle); 1358 if (eatt_bearer != NULL){ 1359 att_server = &eatt_bearer->att_server; 1360 att_connection = &eatt_bearer->att_connection; 1361 packet_buffer = eatt_bearer->send_buffer; 1362 } else 1363 #endif 1364 { 1365 hci_connection_t *hci_connection = hci_connection_for_handle(con_handle); 1366 if (hci_connection != NULL) { 1367 att_server = &hci_connection->att_server; 1368 att_connection = &hci_connection->att_connection; 1369 } 1370 } 1371 1372 if (att_server == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1373 if (!att_server_can_send_packet(att_server, att_connection)) return BTSTACK_ACL_BUFFERS_FULL; 1374 1375 if (packet_buffer == NULL){ 1376 l2cap_reserve_packet_buffer(); 1377 packet_buffer = l2cap_get_outgoing_buffer(); 1378 } 1379 1380 *out_att_connection = att_connection; 1381 *out_att_server = att_server; 1382 *out_packet_buffer = packet_buffer; 1383 return ERROR_CODE_SUCCESS; 1384 } 1385 1386 uint8_t att_server_notify(hci_con_handle_t con_handle, uint16_t attribute_handle, const uint8_t *value, uint16_t value_len){ 1387 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1388 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1389 att_server_t * att_server = &hci_connection->att_server; 1390 att_connection_t * att_connection = &hci_connection->att_connection; 1391 1392 if (!att_server_can_send_packet(att_server, att_connection)) return BTSTACK_ACL_BUFFERS_FULL; 1393 1394 l2cap_reserve_packet_buffer(); 1395 uint8_t * packet_buffer = l2cap_get_outgoing_buffer(); 1396 uint16_t size = att_prepare_handle_value_notification(att_connection, attribute_handle, value, value_len, packet_buffer); 1397 1398 return att_server_send_prepared(att_server, att_connection, NULL, size); 1399 } 1400 1401 /** 1402 * @brief notify client about multiple attribute value changes 1403 * @param con_handle 1404 * @param num_attributes 1405 * @param attribute_handles[] 1406 * @param values_data[] 1407 * @param values_len[] 1408 * @return 0 if ok, error otherwise 1409 */ 1410 uint8_t att_server_multiple_notify(hci_con_handle_t con_handle, uint8_t num_attributes, 1411 const uint16_t * attribute_handles, const uint8_t ** values_data, const uint16_t * values_len){ 1412 1413 att_server_t * att_server = NULL; 1414 att_connection_t * att_connection = NULL; 1415 uint8_t * packet_buffer = NULL; 1416 1417 uint8_t status = att_server_prepare_server_message(con_handle, &att_server, &att_connection, &packet_buffer); 1418 if (status != ERROR_CODE_SUCCESS){ 1419 return status; 1420 } 1421 1422 uint16_t size = att_prepare_handle_value_multiple_notification(att_connection, num_attributes, attribute_handles, values_data, values_len, packet_buffer); 1423 1424 return att_server_send_prepared(att_server, att_connection, packet_buffer, size); 1425 } 1426 1427 uint8_t att_server_indicate(hci_con_handle_t con_handle, uint16_t attribute_handle, const uint8_t *value, uint16_t value_len){ 1428 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1429 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1430 att_server_t * att_server = &hci_connection->att_server; 1431 att_connection_t * att_connection = &hci_connection->att_connection; 1432 1433 if (att_server->value_indication_handle != 0u) return ATT_HANDLE_VALUE_INDICATION_IN_PROGRESS; 1434 if (!att_server_can_send_packet(att_server, att_connection)) return BTSTACK_ACL_BUFFERS_FULL; 1435 1436 // track indication 1437 att_server->value_indication_handle = attribute_handle; 1438 btstack_run_loop_set_timer_handler(&att_server->value_indication_timer, att_handle_value_indication_timeout); 1439 btstack_run_loop_set_timer(&att_server->value_indication_timer, ATT_TRANSACTION_TIMEOUT_MS); 1440 btstack_run_loop_add_timer(&att_server->value_indication_timer); 1441 1442 l2cap_reserve_packet_buffer(); 1443 uint8_t * packet_buffer = l2cap_get_outgoing_buffer(); 1444 uint16_t size = att_prepare_handle_value_indication(att_connection, attribute_handle, value, value_len, packet_buffer); 1445 1446 return att_server_send_prepared(att_server, att_connection, NULL, size); 1447 } 1448 1449 uint16_t att_server_get_mtu(hci_con_handle_t con_handle){ 1450 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1451 if (!hci_connection) return 0; 1452 att_connection_t * att_connection = &hci_connection->att_connection; 1453 return att_connection->mtu; 1454 } 1455 1456 void att_server_deinit(void){ 1457 att_server_client_read_callback = NULL; 1458 att_server_client_write_callback = NULL; 1459 att_client_packet_handler = NULL; 1460 service_handlers = NULL; 1461 } 1462 1463 #ifdef ENABLE_GATT_OVER_EATT 1464 1465 #define MAX_NR_EATT_CHANNELS 5 1466 1467 static uint16_t att_server_eatt_receive_buffer_size; 1468 static uint16_t att_server_eatt_send_buffer_size; 1469 1470 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_cid(uint16_t cid){ 1471 btstack_linked_list_iterator_t it; 1472 btstack_linked_list_iterator_init(&it, &att_server_eatt_bearer_active); 1473 while(btstack_linked_list_iterator_has_next(&it)){ 1474 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) btstack_linked_list_iterator_next(&it); 1475 if (eatt_bearer->att_server.l2cap_cid == cid) { 1476 return eatt_bearer; 1477 } 1478 } 1479 return NULL; 1480 } 1481 1482 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_con_handle(hci_con_handle_t con_handle){ 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_connection.con_handle == con_handle) { 1488 return eatt_bearer; 1489 } 1490 } 1491 return NULL; 1492 } 1493 1494 static void att_server_eatt_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 1495 uint16_t cid; 1496 uint8_t status; 1497 uint16_t remote_mtu; 1498 1499 uint8_t i; 1500 uint8_t num_requested_bearers; 1501 uint8_t num_accepted_bearers; 1502 uint16_t initial_credits = L2CAP_LE_AUTOMATIC_CREDITS; 1503 uint8_t * receive_buffers[MAX_NR_EATT_CHANNELS]; 1504 uint16_t cids[MAX_NR_EATT_CHANNELS]; 1505 att_server_eatt_bearer_t * eatt_bearers[MAX_NR_EATT_CHANNELS]; 1506 att_server_eatt_bearer_t * eatt_bearer; 1507 att_server_t * att_server; 1508 att_connection_t * att_connection; 1509 1510 switch (packet_type) { 1511 1512 case L2CAP_DATA_PACKET: 1513 eatt_bearer = att_server_eatt_bearer_for_cid(channel); 1514 btstack_assert(eatt_bearer != NULL); 1515 att_server = &eatt_bearer->att_server; 1516 att_connection = &eatt_bearer->att_connection; 1517 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1518 break; 1519 1520 case HCI_EVENT_PACKET: 1521 switch (packet[0]) { 1522 1523 case L2CAP_EVENT_CAN_SEND_NOW: 1524 cid = l2cap_event_packet_sent_get_local_cid(packet); 1525 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1526 btstack_assert(eatt_bearer != NULL); 1527 att_server = &eatt_bearer->att_server; 1528 att_connection = &eatt_bearer->att_connection; 1529 // only used for EATT request responses 1530 btstack_assert(att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED); 1531 att_server_process_validated_request(att_server, att_connection, eatt_bearer->send_buffer); 1532 break; 1533 1534 case L2CAP_EVENT_PACKET_SENT: 1535 cid = l2cap_event_packet_sent_get_local_cid(packet); 1536 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1537 btstack_assert(eatt_bearer != NULL); 1538 att_server = &eatt_bearer->att_server; 1539 att_connection = &eatt_bearer->att_connection; 1540 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1541 break; 1542 1543 case L2CAP_EVENT_ECBM_INCOMING_CONNECTION: 1544 cid = l2cap_event_ecbm_incoming_connection_get_local_cid(packet); 1545 num_requested_bearers = l2cap_event_ecbm_incoming_connection_get_num_channels(packet); 1546 for (i = 0; i < num_requested_bearers; i++){ 1547 eatt_bearers[i] = (att_server_eatt_bearer_t *) btstack_linked_list_pop(&att_server_eatt_bearer_pool); 1548 if (eatt_bearers[i] == NULL) { 1549 break; 1550 } 1551 eatt_bearers[i]->att_connection.con_handle = l2cap_event_ecbm_incoming_connection_get_handle(packet); 1552 eatt_bearers[i]->att_server.bearer_type = ATT_BEARER_ENHANCED_LE; 1553 receive_buffers[i] = eatt_bearers[i]->receive_buffer; 1554 btstack_linked_list_add(&att_server_eatt_bearer_active, (btstack_linked_item_t *) eatt_bearers[i]); 1555 } 1556 num_accepted_bearers = i; 1557 status = l2cap_ecbm_accept_channels(cid, num_accepted_bearers, initial_credits, att_server_eatt_receive_buffer_size, receive_buffers, cids); 1558 btstack_assert(status == ERROR_CODE_SUCCESS); 1559 log_info("requested %u, accepted %u", num_requested_bearers, num_accepted_bearers); 1560 for (i=0;i<num_accepted_bearers;i++){ 1561 log_info("eatt l2cap cid: 0x%04x", cids[i]); 1562 eatt_bearers[i]->att_server.l2cap_cid = cids[i]; 1563 } 1564 break; 1565 1566 case L2CAP_EVENT_ECBM_CHANNEL_OPENED: 1567 cid = l2cap_event_ecbm_channel_opened_get_local_cid(packet); 1568 status = l2cap_event_ecbm_channel_opened_get_status(packet); 1569 remote_mtu = l2cap_event_ecbm_channel_opened_get_remote_mtu(packet); 1570 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1571 btstack_assert(eatt_bearer != NULL); 1572 eatt_bearer->att_connection.mtu_exchanged = true; 1573 eatt_bearer->att_connection.mtu = remote_mtu; 1574 eatt_bearer->att_connection.max_mtu = remote_mtu; 1575 log_info("L2CAP_EVENT_ECBM_CHANNEL_OPENED - cid 0x%04x mtu %u, status 0x%02x", cid, remote_mtu, status); 1576 break; 1577 1578 case L2CAP_EVENT_ECBM_RECONFIGURED: 1579 break; 1580 1581 case L2CAP_EVENT_CHANNEL_CLOSED: 1582 eatt_bearer = att_server_eatt_bearer_for_cid(l2cap_event_channel_closed_get_local_cid(packet)); 1583 btstack_assert(eatt_bearers != NULL); 1584 1585 // TODO: finalize - abort queued writes 1586 1587 btstack_linked_list_remove(&att_server_eatt_bearer_active, (btstack_linked_item_t *) eatt_bearer); 1588 btstack_linked_list_add(&att_server_eatt_bearer_pool, (btstack_linked_item_t *) eatt_bearer); 1589 break; 1590 default: 1591 break; 1592 } 1593 break; 1594 default: 1595 btstack_unreachable(); 1596 break; 1597 } 1598 } 1599 1600 // create eatt bearers 1601 uint8_t att_server_eatt_init(uint8_t num_eatt_bearers, uint8_t * storage_buffer, uint16_t storage_size){ 1602 uint16_t size_for_structs = num_eatt_bearers * sizeof(att_server_eatt_bearer_t); 1603 if (storage_size < size_for_structs) { 1604 return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED; 1605 } 1606 1607 // TODO: The minimum ATT_MTU for an Enhanced ATT bearer is 64 octets. 1608 1609 memset(storage_buffer, 0, storage_size); 1610 uint16_t buffer_size_per_bearer = ((storage_size - size_for_structs) / num_eatt_bearers); 1611 att_server_eatt_receive_buffer_size = buffer_size_per_bearer / 2; 1612 att_server_eatt_send_buffer_size = buffer_size_per_bearer / 2; 1613 uint8_t * bearer_buffer = &storage_buffer[size_for_structs]; 1614 uint8_t i; 1615 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) storage_buffer; 1616 log_info("%u EATT bearers with receive buffer size %u", 1617 num_eatt_bearers, att_server_eatt_receive_buffer_size); 1618 for (i=0;i<num_eatt_bearers;i++){ 1619 eatt_bearer->att_connection.con_handle = HCI_CON_HANDLE_INVALID; 1620 eatt_bearer->receive_buffer = bearer_buffer; 1621 bearer_buffer += att_server_eatt_receive_buffer_size; 1622 eatt_bearer->send_buffer = bearer_buffer; 1623 bearer_buffer += att_server_eatt_send_buffer_size; 1624 btstack_linked_list_add(&att_server_eatt_bearer_pool, (btstack_linked_item_t *) eatt_bearer); 1625 eatt_bearer++; 1626 } 1627 // TODO: define minimum EATT MTU 1628 l2cap_ecbm_register_service(att_server_eatt_handler, BLUETOOTH_PSM_EATT, 64, 0); 1629 1630 return 0; 1631 } 1632 #endif