1 /* 2 * Copyright (C) 2014 BlueKitchen GmbH 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 4. Any redistribution, use, or modification is done solely for 17 * personal benefit and not for any commercial purpose or for 18 * monetary gain. 19 * 20 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN 24 * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Please inquire about commercial licensing options at 34 * [email protected] 35 * 36 */ 37 38 #define BTSTACK_FILE__ "att_server.c" 39 40 41 // 42 // ATT Server Globals 43 // 44 45 #include <stdint.h> 46 #include <string.h> 47 #include <inttypes.h> 48 49 #include "btstack_config.h" 50 51 #include "ble/att_dispatch.h" 52 #include "ble/att_db.h" 53 #include "ble/att_server.h" 54 #include "ble/core.h" 55 #include "ble/le_device_db.h" 56 #include "ble/sm.h" 57 #include "btstack_debug.h" 58 #include "btstack_event.h" 59 #include "btstack_memory.h" 60 #include "btstack_run_loop.h" 61 #include "gap.h" 62 #include "hci.h" 63 #include "hci_dump.h" 64 #include "l2cap.h" 65 #include "btstack_tlv.h" 66 #ifdef ENABLE_LE_SIGNED_WRITE 67 #include "ble/sm.h" 68 #include "bluetooth_psm.h" 69 70 #endif 71 72 #ifdef ENABLE_TESTING_SUPPORT 73 #include <stdio.h> 74 #endif 75 76 #ifndef NVN_NUM_GATT_SERVER_CCC 77 #define NVN_NUM_GATT_SERVER_CCC 20 78 #endif 79 80 static void att_run_for_context(att_server_t * att_server, att_connection_t * att_connection); 81 static att_write_callback_t att_server_write_callback_for_handle(uint16_t handle); 82 static btstack_packet_handler_t att_server_packet_handler_for_handle(uint16_t handle); 83 static void att_server_handle_can_send_now(void); 84 static void att_server_persistent_ccc_restore(att_server_t * att_server, att_connection_t * att_connection); 85 static void att_server_persistent_ccc_clear(att_server_t * att_server); 86 static void att_server_handle_att_pdu(att_server_t * att_server, att_connection_t * att_connection, uint8_t * packet, uint16_t size); 87 88 typedef enum { 89 ATT_SERVER_RUN_PHASE_1_REQUESTS = 0, 90 ATT_SERVER_RUN_PHASE_2_INDICATIONS, 91 ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS, 92 } att_server_run_phase_t; 93 94 // 95 typedef struct { 96 uint32_t seq_nr; 97 uint16_t att_handle; 98 uint8_t value; 99 uint8_t device_index; 100 } persistent_ccc_entry_t; 101 102 // global 103 static btstack_packet_callback_registration_t hci_event_callback_registration; 104 static btstack_packet_callback_registration_t sm_event_callback_registration; 105 static btstack_packet_handler_t att_client_packet_handler; 106 static btstack_linked_list_t service_handlers; 107 static btstack_context_callback_registration_t att_client_waiting_for_can_send_registration; 108 109 static att_read_callback_t att_server_client_read_callback; 110 static att_write_callback_t att_server_client_write_callback; 111 112 // round robin 113 static hci_con_handle_t att_server_last_can_send_now = HCI_CON_HANDLE_INVALID; 114 115 #ifdef ENABLE_GATT_OVER_EATT 116 typedef struct { 117 btstack_linked_item_t item; 118 att_server_t att_server; 119 att_connection_t att_connection; 120 uint8_t * receive_buffer; 121 uint8_t * send_buffer; 122 } att_server_eatt_bearer_t; 123 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_con_handle(hci_con_handle_t con_handle); 124 static btstack_linked_list_t att_server_eatt_bearer_pool; 125 static btstack_linked_list_t att_server_eatt_bearer_active; 126 #endif 127 128 #ifdef ENABLE_LE_SIGNED_WRITE 129 static bool att_server_connections_for_state(att_server_state_t state, att_server_t ** att_server_out, att_connection_t ** att_connection_out){ 130 btstack_linked_list_iterator_t it; 131 hci_connections_get_iterator(&it); 132 while(btstack_linked_list_iterator_has_next(&it)){ 133 hci_connection_t * hci_connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 134 if (hci_connection->att_server.state == state) { 135 *att_server_out = &hci_connection->att_server; 136 *att_connection_out = &hci_connection->att_connection; 137 return true; 138 } 139 } 140 141 #ifdef ENABLE_GATT_OVER_EATT 142 btstack_linked_list_iterator_init(&it, &att_server_eatt_bearer_active); 143 while(btstack_linked_list_iterator_has_next(&it)){ 144 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) btstack_linked_list_iterator_next(&it); 145 if (eatt_bearer->att_server.state == state) { 146 *att_server_out = &eatt_bearer->att_server; 147 *att_connection_out = &eatt_bearer->att_connection; 148 return true; 149 } 150 } 151 #endif 152 153 return false; 154 } 155 #endif 156 157 static void att_server_request_can_send_now(att_server_t * att_server, att_connection_t * att_connection ){ 158 switch (att_server->bearer_type){ 159 case ATT_BEARER_UNENHANCED_LE: 160 #ifdef ENABLE_GATT_OVER_CLASSIC 161 case ATT_BEARER_UNENHANCED_CLASSIC: 162 /* fall through */ 163 #endif 164 att_dispatch_server_request_can_send_now_event(att_connection->con_handle); 165 break; 166 #ifdef ENABLE_GATT_OVER_EATT 167 case ATT_BEARER_ENHANCED_LE: 168 l2cap_request_can_send_now_event(att_server->l2cap_cid); 169 break; 170 #endif 171 default: 172 btstack_unreachable(); 173 break; 174 } 175 } 176 177 static bool att_server_can_send_packet(att_server_t * att_server, att_connection_t * att_connection){ 178 switch (att_server->bearer_type) { 179 case ATT_BEARER_UNENHANCED_LE: 180 #ifdef ENABLE_GATT_OVER_CLASSIC 181 case ATT_BEARER_UNENHANCED_CLASSIC: 182 /* fall through */ 183 #endif 184 return att_dispatch_server_can_send_now(att_connection->con_handle); 185 #ifdef ENABLE_GATT_OVER_EATT 186 case ATT_BEARER_ENHANCED_LE: 187 return l2cap_can_send_packet_now(att_server->l2cap_cid); 188 #endif 189 default: 190 btstack_unreachable(); 191 break; 192 } 193 return false; 194 } 195 196 static void att_handle_value_indication_notify_client(uint8_t status, uint16_t client_handle, uint16_t attribute_handle){ 197 btstack_packet_handler_t packet_handler = att_server_packet_handler_for_handle(attribute_handle); 198 if (!packet_handler) return; 199 200 uint8_t event[7]; 201 int pos = 0; 202 event[pos++] = ATT_EVENT_HANDLE_VALUE_INDICATION_COMPLETE; 203 event[pos++] = sizeof(event) - 2u; 204 event[pos++] = status; 205 little_endian_store_16(event, pos, client_handle); 206 pos += 2; 207 little_endian_store_16(event, pos, attribute_handle); 208 (*packet_handler)(HCI_EVENT_PACKET, 0, &event[0], sizeof(event)); 209 } 210 211 static void att_emit_event_to_all(const uint8_t * event, uint16_t size){ 212 // dispatch to app level handler 213 if (att_client_packet_handler != NULL){ 214 (*att_client_packet_handler)(HCI_EVENT_PACKET, 0, (uint8_t*) event, size); 215 } 216 217 // dispatch to service handlers 218 btstack_linked_list_iterator_t it; 219 btstack_linked_list_iterator_init(&it, &service_handlers); 220 while (btstack_linked_list_iterator_has_next(&it)){ 221 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 222 if (!handler->packet_handler) continue; 223 (*handler->packet_handler)(HCI_EVENT_PACKET, 0, (uint8_t*) event, size); 224 } 225 } 226 227 static void att_emit_mtu_event(hci_con_handle_t con_handle, uint16_t mtu){ 228 uint8_t event[6]; 229 int pos = 0; 230 event[pos++] = ATT_EVENT_MTU_EXCHANGE_COMPLETE; 231 event[pos++] = sizeof(event) - 2u; 232 little_endian_store_16(event, pos, con_handle); 233 pos += 2; 234 little_endian_store_16(event, pos, mtu); 235 236 // also dispatch to GATT Clients 237 att_dispatch_server_mtu_exchanged(con_handle, mtu); 238 239 // dispatch to app level handler and service handlers 240 att_emit_event_to_all(&event[0], sizeof(event)); 241 } 242 243 static void att_emit_can_send_now_event(void * context){ 244 UNUSED(context); 245 if (!att_client_packet_handler) return; 246 247 uint8_t event[] = { ATT_EVENT_CAN_SEND_NOW, 0}; 248 (*att_client_packet_handler)(HCI_EVENT_PACKET, 0, &event[0], sizeof(event)); 249 } 250 251 static void att_emit_connected_event(att_server_t * att_server, att_connection_t * att_connection){ 252 uint8_t event[11]; 253 int pos = 0; 254 event[pos++] = ATT_EVENT_CONNECTED; 255 event[pos++] = sizeof(event) - 2u; 256 event[pos++] = att_server->peer_addr_type; 257 reverse_bd_addr(att_server->peer_address, &event[pos]); 258 pos += 6; 259 little_endian_store_16(event, pos, att_connection->con_handle); 260 pos += 2; 261 262 // dispatch to app level handler and service handlers 263 att_emit_event_to_all(&event[0], sizeof(event)); 264 } 265 266 267 static void att_emit_disconnected_event(uint16_t con_handle){ 268 uint8_t event[4]; 269 int pos = 0; 270 event[pos++] = ATT_EVENT_DISCONNECTED; 271 event[pos++] = sizeof(event) - 2u; 272 little_endian_store_16(event, pos, con_handle); 273 pos += 2; 274 275 // dispatch to app level handler and service handlers 276 att_emit_event_to_all(&event[0], sizeof(event)); 277 } 278 279 static void att_handle_value_indication_timeout(btstack_timer_source_t *ts){ 280 void * context = btstack_run_loop_get_timer_context(ts); 281 hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) context; 282 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 283 if (!hci_connection) return; 284 // @note: after a transaction timeout, no more requests shall be sent over this ATT Bearer 285 // (that's why we don't reset the value_indication_handle) 286 att_server_t * att_server = &hci_connection->att_server; 287 uint16_t att_handle = att_server->value_indication_handle; 288 att_connection_t * att_connection = &hci_connection->att_connection; 289 att_handle_value_indication_notify_client((uint8_t)ATT_HANDLE_VALUE_INDICATION_TIMEOUT, att_connection->con_handle, att_handle); 290 } 291 292 static void att_server_event_packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 293 294 UNUSED(channel); // ok: there is no channel 295 UNUSED(size); // ok: handling own l2cap events 296 297 att_server_t * att_server; 298 att_connection_t * att_connection; 299 hci_con_handle_t con_handle; 300 hci_connection_t * hci_connection; 301 302 switch (packet_type) { 303 304 case HCI_EVENT_PACKET: 305 switch (hci_event_packet_get_type(packet)) { 306 case HCI_EVENT_LE_META: 307 switch (packet[2]) { 308 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE: 309 con_handle = little_endian_read_16(packet, 4); 310 hci_connection = hci_connection_for_handle(con_handle); 311 if (!hci_connection) break; 312 att_server = &hci_connection->att_server; 313 // store connection info 314 att_server->peer_addr_type = packet[7]; 315 reverse_bd_addr(&packet[8], att_server->peer_address); 316 att_connection = &hci_connection->att_connection; 317 att_connection->con_handle = con_handle; 318 // reset connection properties 319 att_server->state = ATT_SERVER_IDLE; 320 att_server->bearer_type = ATT_BEARER_UNENHANCED_LE; 321 att_connection->mtu = ATT_DEFAULT_MTU; 322 att_connection->max_mtu = l2cap_max_le_mtu(); 323 if (att_connection->max_mtu > ATT_REQUEST_BUFFER_SIZE){ 324 att_connection->max_mtu = ATT_REQUEST_BUFFER_SIZE; 325 } 326 att_connection->encryption_key_size = 0u; 327 att_connection->authenticated = 0u; 328 att_connection->authorized = 0u; 329 // workaround: identity resolving can already be complete, at least store result 330 att_server->ir_le_device_db_index = sm_le_device_index(con_handle); 331 att_server->ir_lookup_active = 0u; 332 att_server->pairing_active = 0u; 333 // notify all - old 334 att_emit_event_to_all(packet, size); 335 // notify all - new 336 att_emit_connected_event(att_server, att_connection); 337 break; 338 339 default: 340 break; 341 } 342 break; 343 344 case HCI_EVENT_ENCRYPTION_CHANGE: 345 case HCI_EVENT_ENCRYPTION_CHANGE_V2: 346 case HCI_EVENT_ENCRYPTION_KEY_REFRESH_COMPLETE: 347 // check handle 348 con_handle = little_endian_read_16(packet, 3); 349 hci_connection = hci_connection_for_handle(con_handle); 350 if (!hci_connection) break; 351 if (gap_get_connection_type(con_handle) != GAP_CONNECTION_LE) break; 352 // update security params 353 att_server = &hci_connection->att_server; 354 att_connection = &hci_connection->att_connection; 355 att_connection->encryption_key_size = gap_encryption_key_size(con_handle); 356 att_connection->authenticated = gap_authenticated(con_handle) ? 1 : 0; 357 att_connection->secure_connection = gap_secure_connection(con_handle) ? 1 : 0; 358 log_info("encrypted key size %u, authenticated %u, secure connection %u", 359 att_connection->encryption_key_size, att_connection->authenticated, att_connection->secure_connection); 360 if (hci_event_packet_get_type(packet) == HCI_EVENT_ENCRYPTION_CHANGE){ 361 // restore CCC values when encrypted for LE Connections 362 if (hci_event_encryption_change_get_encryption_enabled(packet) != 0){ 363 att_server_persistent_ccc_restore(att_server, att_connection); 364 } 365 } 366 att_run_for_context(att_server, att_connection); 367 break; 368 369 case HCI_EVENT_DISCONNECTION_COMPLETE: 370 // check handle 371 con_handle = hci_event_disconnection_complete_get_connection_handle(packet); 372 hci_connection = hci_connection_for_handle(con_handle); 373 if (!hci_connection) break; 374 att_server = &hci_connection->att_server; 375 att_connection = &hci_connection->att_connection; 376 att_clear_transaction_queue(att_connection); 377 att_connection->con_handle = 0; 378 att_server->pairing_active = 0; 379 att_server->state = ATT_SERVER_IDLE; 380 if (att_server->value_indication_handle != 0u){ 381 btstack_run_loop_remove_timer(&att_server->value_indication_timer); 382 uint16_t att_handle = att_server->value_indication_handle; 383 att_server->value_indication_handle = 0u; // reset error state 384 att_handle_value_indication_notify_client((uint8_t)ATT_HANDLE_VALUE_INDICATION_DISCONNECT, att_connection->con_handle, att_handle); 385 } 386 // notify all - new 387 att_emit_disconnected_event(con_handle); 388 // notify all - old 389 att_emit_event_to_all(packet, size); 390 break; 391 392 // Identity Resolving 393 case SM_EVENT_IDENTITY_RESOLVING_STARTED: 394 con_handle = sm_event_identity_resolving_started_get_handle(packet); 395 hci_connection = hci_connection_for_handle(con_handle); 396 if (!hci_connection) break; 397 att_server = &hci_connection->att_server; 398 log_info("SM_EVENT_IDENTITY_RESOLVING_STARTED"); 399 att_server->ir_lookup_active = 1; 400 break; 401 case SM_EVENT_IDENTITY_RESOLVING_SUCCEEDED: 402 con_handle = sm_event_identity_created_get_handle(packet); 403 hci_connection = hci_connection_for_handle(con_handle); 404 if (!hci_connection) return; 405 att_connection = &hci_connection->att_connection; 406 att_server = &hci_connection->att_server; 407 att_server->ir_lookup_active = 0; 408 att_server->ir_le_device_db_index = sm_event_identity_resolving_succeeded_get_index(packet); 409 log_info("SM_EVENT_IDENTITY_RESOLVING_SUCCEEDED"); 410 att_run_for_context(att_server, att_connection); 411 break; 412 case SM_EVENT_IDENTITY_RESOLVING_FAILED: 413 con_handle = sm_event_identity_resolving_failed_get_handle(packet); 414 hci_connection = hci_connection_for_handle(con_handle); 415 if (!hci_connection) break; 416 att_connection = &hci_connection->att_connection; 417 att_server = &hci_connection->att_server; 418 log_info("SM_EVENT_IDENTITY_RESOLVING_FAILED"); 419 att_server->ir_lookup_active = 0; 420 att_server->ir_le_device_db_index = -1; 421 att_run_for_context(att_server, att_connection); 422 break; 423 424 // Pairing started - delete stored CCC values 425 // - assumes pairing indicates either new device or re-pairing, in both cases there should be no stored CCC values 426 // - assumes that all events have the con handle as the first field 427 case SM_EVENT_JUST_WORKS_REQUEST: 428 case SM_EVENT_PASSKEY_DISPLAY_NUMBER: 429 case SM_EVENT_PASSKEY_INPUT_NUMBER: 430 case SM_EVENT_NUMERIC_COMPARISON_REQUEST: 431 con_handle = sm_event_just_works_request_get_handle(packet); 432 hci_connection = hci_connection_for_handle(con_handle); 433 if (!hci_connection) break; 434 att_server = &hci_connection->att_server; 435 log_info("SM Pairing started"); 436 att_server->pairing_active = 1; 437 if (att_server->ir_le_device_db_index < 0) break; 438 att_server_persistent_ccc_clear(att_server); 439 // index not valid anymore 440 att_server->ir_le_device_db_index = -1; 441 break; 442 443 // Bonding completed 444 case SM_EVENT_IDENTITY_CREATED: 445 con_handle = sm_event_identity_created_get_handle(packet); 446 hci_connection = hci_connection_for_handle(con_handle); 447 if (!hci_connection) return; 448 att_connection = &hci_connection->att_connection; 449 att_server = &hci_connection->att_server; 450 att_server->pairing_active = 0; 451 att_server->ir_le_device_db_index = sm_event_identity_created_get_index(packet); 452 att_run_for_context(att_server, att_connection); 453 break; 454 455 // Pairing complete (with/without bonding=storing of pairing information) 456 case SM_EVENT_PAIRING_COMPLETE: 457 con_handle = sm_event_pairing_complete_get_handle(packet); 458 hci_connection = hci_connection_for_handle(con_handle); 459 if (!hci_connection) return; 460 att_connection = &hci_connection->att_connection; 461 att_server = &hci_connection->att_server; 462 att_server->pairing_active = 0; 463 att_run_for_context(att_server, att_connection); 464 break; 465 466 // Authorization 467 case SM_EVENT_AUTHORIZATION_RESULT: { 468 con_handle = sm_event_authorization_result_get_handle(packet); 469 hci_connection = hci_connection_for_handle(con_handle); 470 if (!hci_connection) break; 471 att_connection = &hci_connection->att_connection; 472 att_server = &hci_connection->att_server; 473 att_connection->authorized = sm_event_authorization_result_get_authorization_result(packet); 474 att_server_request_can_send_now(att_server, att_connection); 475 break; 476 } 477 default: 478 break; 479 } 480 break; 481 default: 482 break; 483 } 484 } 485 486 static uint8_t 487 att_server_send_prepared(const att_server_t *att_server, const att_connection_t *att_connection, uint8_t *buffer, 488 uint16_t size) { 489 uint8_t status = ERROR_CODE_SUCCESS; 490 switch (att_server->bearer_type) { 491 case ATT_BEARER_UNENHANCED_LE: 492 status = l2cap_send_prepared_connectionless(att_connection->con_handle, L2CAP_CID_ATTRIBUTE_PROTOCOL, size); 493 break; 494 #ifdef ENABLE_GATT_OVER_CLASSIC 495 case ATT_BEARER_UNENHANCED_CLASSIC: 496 status = l2cap_send_prepared(att_server->l2cap_cid, size); 497 break; 498 #endif 499 #ifdef ENABLE_GATT_OVER_EATT 500 case ATT_BEARER_ENHANCED_LE: 501 btstack_assert(buffer != NULL); 502 status = l2cap_send(att_server->l2cap_cid, buffer, size); 503 break; 504 #endif 505 default: 506 btstack_unreachable(); 507 break; 508 } 509 return status; 510 } 511 512 #ifdef ENABLE_LE_SIGNED_WRITE 513 static void att_signed_write_handle_cmac_result(uint8_t hash[8]){ 514 att_server_t * att_server = NULL; 515 att_connection_t * att_connection = NULL; 516 bool found = att_server_connections_for_state(ATT_SERVER_W4_SIGNED_WRITE_VALIDATION, &att_server, &att_connection); 517 518 if (found == false){ 519 return; 520 } 521 522 uint8_t hash_flipped[8]; 523 reverse_64(hash, hash_flipped); 524 if (memcmp(hash_flipped, &att_server->request_buffer[att_server->request_size-8], 8) != 0){ 525 log_info("ATT Signed Write, invalid signature"); 526 #ifdef ENABLE_TESTING_SUPPORT 527 printf("ATT Signed Write, invalid signature\n"); 528 #endif 529 att_server->state = ATT_SERVER_IDLE; 530 return; 531 } 532 log_info("ATT Signed Write, valid signature"); 533 #ifdef ENABLE_TESTING_SUPPORT 534 printf("ATT Signed Write, valid signature\n"); 535 #endif 536 537 // update sequence number 538 uint32_t counter_packet = little_endian_read_32(att_server->request_buffer, att_server->request_size-12); 539 le_device_db_remote_counter_set(att_server->ir_le_device_db_index, counter_packet+1); 540 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 541 att_server_request_can_send_now(att_server, att_connection); 542 } 543 #endif 544 545 // pre: att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED 546 // pre: can send now 547 // uses l2cap outgoing buffer if no eatt_buffer provided 548 // returns: 1 if packet was sent 549 static int 550 att_server_process_validated_request(att_server_t *att_server, att_connection_t *att_connection, uint8_t *eatt_buffer) { 551 552 uint8_t * att_response_buffer; 553 if (eatt_buffer != NULL){ 554 att_response_buffer = eatt_buffer; 555 } else { 556 l2cap_reserve_packet_buffer(); 557 att_response_buffer = l2cap_get_outgoing_buffer(); 558 } 559 560 uint16_t att_response_size = 0; 561 // Send Error Response for MTU Request over connection-oriented channel 562 if ((att_server->bearer_type != ATT_BEARER_UNENHANCED_LE) && (att_server->request_buffer[0] == ATT_EXCHANGE_MTU_REQUEST)){ 563 att_response_size = 5; 564 att_response_buffer[0] = ATT_ERROR_RESPONSE; 565 att_response_buffer[1] = ATT_EXCHANGE_MTU_REQUEST; 566 att_response_buffer[2] = 0; 567 att_response_buffer[3] = 0; 568 att_response_buffer[4] = ATT_ERROR_REQUEST_NOT_SUPPORTED; 569 } else { 570 att_response_size = att_handle_request(att_connection, att_server->request_buffer, att_server->request_size, att_response_buffer); 571 } 572 573 #ifdef ENABLE_ATT_DELAYED_RESPONSE 574 if ((att_response_size == ATT_READ_RESPONSE_PENDING) || (att_response_size == ATT_INTERNAL_WRITE_RESPONSE_PENDING)){ 575 // update state 576 att_server->state = ATT_SERVER_RESPONSE_PENDING; 577 578 // callback with handle ATT_READ_RESPONSE_PENDING for reads 579 if (att_response_size == ATT_READ_RESPONSE_PENDING){ 580 att_server_client_read_callback(att_connection->con_handle, ATT_READ_RESPONSE_PENDING, 0, NULL, 0); 581 } 582 583 // free reserved buffer 584 if (eatt_buffer == NULL){ 585 l2cap_release_packet_buffer(); 586 } 587 return 0; 588 } 589 #endif 590 591 // intercept "insufficient authorization" for authenticated connections to allow for user authorization 592 if ((att_response_size >= 4u) 593 && (att_response_buffer[0] == ATT_ERROR_RESPONSE) 594 && (att_response_buffer[4] == ATT_ERROR_INSUFFICIENT_AUTHORIZATION) 595 && (att_connection->authenticated != 0u)){ 596 597 switch (gap_authorization_state(att_connection->con_handle)){ 598 case AUTHORIZATION_UNKNOWN: 599 if (eatt_buffer == NULL){ 600 l2cap_release_packet_buffer(); 601 } 602 sm_request_pairing(att_connection->con_handle); 603 return 0; 604 case AUTHORIZATION_PENDING: 605 if (eatt_buffer == NULL){ 606 l2cap_release_packet_buffer(); 607 } 608 return 0; 609 default: 610 break; 611 } 612 } 613 614 att_server->state = ATT_SERVER_IDLE; 615 if (att_response_size == 0u) { 616 if (eatt_buffer == NULL){ 617 l2cap_release_packet_buffer(); 618 } 619 return 0; 620 } 621 622 (void) att_server_send_prepared(att_server, att_connection, eatt_buffer, att_response_size); 623 624 // notify client about MTU exchange result 625 if (att_response_buffer[0] == ATT_EXCHANGE_MTU_RESPONSE){ 626 att_emit_mtu_event(att_connection->con_handle, att_connection->mtu); 627 } 628 return 1; 629 } 630 631 #ifdef ENABLE_ATT_DELAYED_RESPONSE 632 uint8_t att_server_response_ready(hci_con_handle_t con_handle){ 633 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 634 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 635 att_server_t * att_server = &hci_connection->att_server; 636 att_connection_t * att_connection = &hci_connection->att_connection; 637 if (att_server->state != ATT_SERVER_RESPONSE_PENDING) return ERROR_CODE_COMMAND_DISALLOWED; 638 639 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 640 att_server_request_can_send_now(att_server, att_connection); 641 return ERROR_CODE_SUCCESS; 642 } 643 #endif 644 645 static void att_run_for_context(att_server_t * att_server, att_connection_t * att_connection){ 646 switch (att_server->state){ 647 case ATT_SERVER_REQUEST_RECEIVED: 648 switch (att_server->bearer_type){ 649 case ATT_BEARER_UNENHANCED_LE: 650 // wait until re-encryption as central is complete 651 if (gap_reconnect_security_setup_active(att_connection->con_handle)) { 652 return; 653 }; 654 break; 655 #if defined(ENABLE_GATT_OVER_CLASSIC) || defined (ENABLE_GATT_OVER_EATT) 656 #ifdef ENABLE_GATT_OVER_CLASSIC 657 case ATT_BEARER_UNENHANCED_CLASSIC: 658 /* fall through */ 659 #endif 660 #ifdef ENABLE_GATT_OVER_EATT 661 case ATT_BEARER_ENHANCED_LE: 662 #endif 663 // ok 664 break; 665 #endif 666 default: 667 btstack_unreachable(); 668 break; 669 } 670 671 // wait until pairing is complete 672 if (att_server->pairing_active) break; 673 674 #ifdef ENABLE_LE_SIGNED_WRITE 675 if (att_server->request_buffer[0] == ATT_SIGNED_WRITE_COMMAND){ 676 log_info("ATT Signed Write!"); 677 if (!sm_cmac_ready()) { 678 log_info("ATT Signed Write, sm_cmac engine not ready. Abort"); 679 att_server->state = ATT_SERVER_IDLE; 680 return; 681 } 682 if (att_server->request_size < (3 + 12)) { 683 log_info("ATT Signed Write, request to short. Abort."); 684 att_server->state = ATT_SERVER_IDLE; 685 return; 686 } 687 if (att_server->ir_lookup_active){ 688 return; 689 } 690 if (att_server->ir_le_device_db_index < 0){ 691 log_info("ATT Signed Write, CSRK not available"); 692 att_server->state = ATT_SERVER_IDLE; 693 return; 694 } 695 696 // check counter 697 uint32_t counter_packet = little_endian_read_32(att_server->request_buffer, att_server->request_size-12); 698 uint32_t counter_db = le_device_db_remote_counter_get(att_server->ir_le_device_db_index); 699 log_info("ATT Signed Write, DB counter %"PRIu32", packet counter %"PRIu32, counter_db, counter_packet); 700 if (counter_packet < counter_db){ 701 log_info("ATT Signed Write, db reports higher counter, abort"); 702 att_server->state = ATT_SERVER_IDLE; 703 return; 704 } 705 706 // signature is { sequence counter, secure hash } 707 sm_key_t csrk; 708 le_device_db_remote_csrk_get(att_server->ir_le_device_db_index, csrk); 709 att_server->state = ATT_SERVER_W4_SIGNED_WRITE_VALIDATION; 710 log_info("Orig Signature: "); 711 log_info_hexdump( &att_server->request_buffer[att_server->request_size-8], 8); 712 uint16_t attribute_handle = little_endian_read_16(att_server->request_buffer, 1); 713 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); 714 return; 715 } 716 #endif 717 // move on 718 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 719 att_server_request_can_send_now(att_server, att_connection); 720 break; 721 722 default: 723 break; 724 } 725 } 726 727 static bool att_server_data_ready_for_phase(att_server_t * att_server, att_server_run_phase_t phase){ 728 switch (phase){ 729 case ATT_SERVER_RUN_PHASE_1_REQUESTS: 730 return att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 731 case ATT_SERVER_RUN_PHASE_2_INDICATIONS: 732 return (!btstack_linked_list_empty(&att_server->indication_requests) && (att_server->value_indication_handle == 0u)); 733 case ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS: 734 return (!btstack_linked_list_empty(&att_server->notification_requests)); 735 default: 736 btstack_assert(false); 737 return false; 738 } 739 } 740 741 static void att_server_trigger_send_for_phase(att_server_t * att_server, att_connection_t * att_connection, att_server_run_phase_t phase){ 742 btstack_context_callback_registration_t * client; 743 switch (phase){ 744 case ATT_SERVER_RUN_PHASE_1_REQUESTS: 745 att_server_process_validated_request(att_server, att_connection, NULL); 746 break; 747 case ATT_SERVER_RUN_PHASE_2_INDICATIONS: 748 client = (btstack_context_callback_registration_t*) att_server->indication_requests; 749 btstack_linked_list_remove(&att_server->indication_requests, (btstack_linked_item_t *) client); 750 client->callback(client->context); 751 break; 752 case ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS: 753 client = (btstack_context_callback_registration_t*) att_server->notification_requests; 754 btstack_linked_list_remove(&att_server->notification_requests, (btstack_linked_item_t *) client); 755 client->callback(client->context); 756 break; 757 default: 758 btstack_assert(false); 759 break; 760 } 761 } 762 763 static void att_server_handle_can_send_now(void){ 764 765 hci_con_handle_t last_send_con_handle = HCI_CON_HANDLE_INVALID; 766 hci_connection_t * request_hci_connection = NULL; 767 bool can_send_now = true; 768 uint8_t phase_index; 769 770 for (phase_index = ATT_SERVER_RUN_PHASE_1_REQUESTS; phase_index <= ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS; phase_index++){ 771 att_server_run_phase_t phase = (att_server_run_phase_t) phase_index; 772 hci_con_handle_t skip_connections_until = att_server_last_can_send_now; 773 while (true){ 774 btstack_linked_list_iterator_t it; 775 hci_connections_get_iterator(&it); 776 while(btstack_linked_list_iterator_has_next(&it)){ 777 hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 778 att_server_t * att_server = &connection->att_server; 779 att_connection_t * att_connection = &connection->att_connection; 780 781 bool data_ready = att_server_data_ready_for_phase(att_server, phase); 782 783 // log_debug("phase %u, handle 0x%04x, skip until 0x%04x, data ready %u", phase, att_connection->con_handle, skip_connections_until, data_ready); 784 785 // skip until last sender found (which is also skipped) 786 if (skip_connections_until != HCI_CON_HANDLE_INVALID){ 787 if (data_ready && (request_hci_connection == NULL)){ 788 request_hci_connection = connection; 789 } 790 if (skip_connections_until == att_connection->con_handle){ 791 skip_connections_until = HCI_CON_HANDLE_INVALID; 792 } 793 continue; 794 }; 795 796 if (data_ready){ 797 if (can_send_now){ 798 att_server_trigger_send_for_phase(att_server, att_connection, phase); 799 last_send_con_handle = att_connection->con_handle; 800 can_send_now = att_server_can_send_packet(att_server, att_connection); 801 data_ready = att_server_data_ready_for_phase(att_server, phase); 802 if (data_ready && (request_hci_connection == NULL)){ 803 request_hci_connection = connection; 804 } 805 } else { 806 request_hci_connection = connection; 807 break; 808 } 809 } 810 } 811 812 // stop skipping (handles disconnect by last send connection) 813 skip_connections_until = HCI_CON_HANDLE_INVALID; 814 815 // Exit loop, if we cannot send 816 if (!can_send_now) break; 817 818 // Exit loop, if we can send but there are also no further request 819 if (request_hci_connection == NULL) break; 820 821 // Finally, if we still can send and there are requests, just try again 822 request_hci_connection = NULL; 823 } 824 // update last send con handle for round robin 825 if (last_send_con_handle != HCI_CON_HANDLE_INVALID){ 826 att_server_last_can_send_now = last_send_con_handle; 827 } 828 } 829 830 if (request_hci_connection == NULL) return; 831 832 att_server_t * att_server = &request_hci_connection->att_server; 833 att_connection_t * att_connection = &request_hci_connection->att_connection; 834 att_server_request_can_send_now(att_server, att_connection); 835 } 836 837 static void att_server_handle_att_pdu(att_server_t * att_server, att_connection_t * att_connection, uint8_t * packet, uint16_t size){ 838 839 uint8_t opcode = packet[0u]; 840 uint8_t method = opcode & 0x03fu; 841 bool invalid = method > ATT_MULTIPLE_HANDLE_VALUE_NTF; 842 bool command = (opcode & 0x40u) != 0u; 843 844 // ignore invalid commands 845 if (invalid && command){ 846 return; 847 } 848 849 // handle value indication confirms 850 if ((opcode == ATT_HANDLE_VALUE_CONFIRMATION) && (att_server->value_indication_handle != 0u)){ 851 btstack_run_loop_remove_timer(&att_server->value_indication_timer); 852 uint16_t att_handle = att_server->value_indication_handle; 853 att_server->value_indication_handle = 0u; 854 att_handle_value_indication_notify_client(0u, att_connection->con_handle, att_handle); 855 att_server_request_can_send_now(att_server, att_connection); 856 return; 857 } 858 859 // directly process command 860 // note: signed write cannot be handled directly as authentication needs to be verified 861 if (opcode == ATT_WRITE_COMMAND){ 862 att_handle_request(att_connection, packet, size, NULL); 863 return; 864 } 865 866 // check size 867 if (size > sizeof(att_server->request_buffer)) { 868 log_info("drop att pdu 0x%02x as size %u > att_server->request_buffer %u", packet[0], size, (int) sizeof(att_server->request_buffer)); 869 return; 870 } 871 872 #ifdef ENABLE_LE_SIGNED_WRITE 873 // abort signed write validation if a new request comes in (but finish previous signed write if possible) 874 if (att_server->state == ATT_SERVER_W4_SIGNED_WRITE_VALIDATION){ 875 if (packet[0] == ATT_SIGNED_WRITE_COMMAND){ 876 log_info("skip new signed write request as previous is in validation"); 877 return; 878 } else { 879 log_info("abort signed write validation to process new request"); 880 att_server->state = ATT_SERVER_IDLE; 881 } 882 } 883 #endif 884 // last request still in processing? 885 if (att_server->state != ATT_SERVER_IDLE){ 886 log_info("skip att pdu 0x%02x as server not idle (state %u)", packet[0], att_server->state); 887 return; 888 } 889 890 // store request 891 att_server->state = ATT_SERVER_REQUEST_RECEIVED; 892 att_server->request_size = size; 893 (void)memcpy(att_server->request_buffer, packet, size); 894 895 att_run_for_context(att_server, att_connection); 896 } 897 898 static void att_server_dispatch_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 899 hci_connection_t * hci_connection; 900 att_connection_t * att_connection; 901 att_server_t * att_server; 902 #ifdef ENABLE_GATT_OVER_CLASSIC 903 hci_con_handle_t con_handle; 904 bd_addr_t address; 905 btstack_linked_list_iterator_t it; 906 #endif 907 908 switch (packet_type){ 909 case HCI_EVENT_PACKET: 910 switch (packet[0]){ 911 #ifdef ENABLE_GATT_OVER_CLASSIC 912 case L2CAP_EVENT_CHANNEL_OPENED: 913 con_handle = l2cap_event_channel_opened_get_handle(packet); 914 hci_connection = hci_connection_for_handle(con_handle); 915 if (!hci_connection) break; 916 att_server = &hci_connection->att_server; 917 // store connection info 918 att_server->bearer_type = ATT_BEARER_UNENHANCED_CLASSIC; 919 att_server->peer_addr_type = BD_ADDR_TYPE_ACL; 920 l2cap_event_channel_opened_get_address(packet, att_server->peer_address); 921 att_connection = &hci_connection->att_connection; 922 att_connection->con_handle = con_handle; 923 // reset connection properties 924 att_server->state = ATT_SERVER_IDLE; 925 att_connection->mtu = l2cap_event_channel_opened_get_remote_mtu(packet); 926 att_connection->max_mtu = l2cap_max_mtu(); 927 if (att_connection->max_mtu > ATT_REQUEST_BUFFER_SIZE){ 928 att_connection->max_mtu = ATT_REQUEST_BUFFER_SIZE; 929 } 930 931 log_info("Connection opened %s, l2cap cid %04x, mtu %u", bd_addr_to_str(address), att_server->l2cap_cid, att_connection->mtu); 932 933 // update security params 934 att_connection->encryption_key_size = gap_encryption_key_size(con_handle); 935 att_connection->authenticated = gap_authenticated(con_handle); 936 att_connection->secure_connection = gap_secure_connection(con_handle); 937 log_info("encrypted key size %u, authenticated %u, secure connection %u", 938 att_connection->encryption_key_size, att_connection->authenticated, att_connection->secure_connection); 939 940 // notify connection opened 941 att_emit_connected_event(att_server, att_connection); 942 943 // restore persisten ccc if encrypted 944 if ( gap_security_level(con_handle) >= LEVEL_2){ 945 att_server_persistent_ccc_restore(att_server, att_connection); 946 } 947 // TODO: what to do about le device db? 948 att_server->pairing_active = 0; 949 break; 950 #endif 951 case L2CAP_EVENT_CAN_SEND_NOW: 952 att_server_handle_can_send_now(); 953 break; 954 case ATT_EVENT_MTU_EXCHANGE_COMPLETE: 955 // GATT client has negotiated the mtu for this connection 956 hci_connection = hci_connection_for_handle(channel); 957 if (!hci_connection) break; 958 att_connection = &hci_connection->att_connection; 959 att_connection->mtu = little_endian_read_16(packet, 4); 960 break; 961 default: 962 break; 963 } 964 break; 965 966 case ATT_DATA_PACKET: 967 log_debug("ATT Packet, handle 0x%04x", channel); 968 hci_connection = hci_connection_for_handle(channel); 969 if (!hci_connection) break; 970 971 att_server = &hci_connection->att_server; 972 att_connection = &hci_connection->att_connection; 973 att_server_handle_att_pdu(att_server, att_connection, packet, size); 974 break; 975 976 #ifdef ENABLE_GATT_OVER_CLASSIC 977 case L2CAP_DATA_PACKET: 978 hci_connections_get_iterator(&it); 979 while(btstack_linked_list_iterator_has_next(&it)){ 980 hci_connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 981 att_server = &hci_connection->att_server; 982 att_connection = &hci_connection->att_connection; 983 if (att_server->l2cap_cid == channel) { 984 att_server_handle_att_pdu(att_server, att_connection, packet, size); 985 break; 986 } 987 } 988 break; 989 #endif 990 991 default: 992 break; 993 } 994 } 995 996 // --------------------- 997 // persistent CCC writes 998 static uint32_t att_server_persistent_ccc_tag_for_index(uint8_t index){ 999 return ('B' << 24u) | ('T' << 16u) | ('C' << 8u) | index; 1000 } 1001 1002 static void att_server_persistent_ccc_write(hci_con_handle_t con_handle, uint16_t att_handle, uint16_t value){ 1003 // lookup att_server instance 1004 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1005 if (!hci_connection) return; 1006 att_server_t * att_server = &hci_connection->att_server; 1007 int le_device_index = att_server->ir_le_device_db_index; 1008 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); 1009 1010 // check if bonded 1011 if (le_device_index < 0) return; 1012 1013 // get btstack_tlv 1014 const btstack_tlv_t * tlv_impl = NULL; 1015 void * tlv_context; 1016 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1017 if (!tlv_impl) return; 1018 1019 // update ccc tag 1020 int index; 1021 uint32_t highest_seq_nr = 0; 1022 uint32_t lowest_seq_nr = 0; 1023 uint32_t tag_for_lowest_seq_nr = 0; 1024 uint32_t tag_for_empty = 0; 1025 persistent_ccc_entry_t entry; 1026 for (index=0; index<NVN_NUM_GATT_SERVER_CCC; index++){ 1027 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1028 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1029 1030 // empty/invalid tag 1031 if (len != sizeof(persistent_ccc_entry_t)){ 1032 tag_for_empty = tag; 1033 continue; 1034 } 1035 // update highest seq nr 1036 if (entry.seq_nr > highest_seq_nr){ 1037 highest_seq_nr = entry.seq_nr; 1038 } 1039 // find entry with lowest seq nr 1040 if ((tag_for_lowest_seq_nr == 0u) || (entry.seq_nr < lowest_seq_nr)){ 1041 tag_for_lowest_seq_nr = tag; 1042 lowest_seq_nr = entry.seq_nr; 1043 } 1044 1045 if (entry.device_index != le_device_index) continue; 1046 if (entry.att_handle != att_handle) continue; 1047 1048 // found matching entry 1049 if (value != 0){ 1050 // update 1051 if (entry.value == value) { 1052 log_info("CCC Index %u: Up-to-date", index); 1053 return; 1054 } 1055 entry.value = (uint8_t) value; 1056 entry.seq_nr = highest_seq_nr + 1u; 1057 log_info("CCC Index %u: Store", index); 1058 int result = tlv_impl->store_tag(tlv_context, tag, (const uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1059 if (result != 0){ 1060 log_error("Store tag index %u failed", index); 1061 } 1062 } else { 1063 // delete 1064 log_info("CCC Index %u: Delete", index); 1065 tlv_impl->delete_tag(tlv_context, tag); 1066 } 1067 return; 1068 } 1069 1070 log_info("tag_for_empty %"PRIx32", tag_for_lowest_seq_nr %"PRIx32, tag_for_empty, tag_for_lowest_seq_nr); 1071 1072 if (value == 0u){ 1073 // done 1074 return; 1075 } 1076 1077 uint32_t tag_to_use = 0u; 1078 if (tag_for_empty != 0u){ 1079 tag_to_use = tag_for_empty; 1080 } else if (tag_for_lowest_seq_nr){ 1081 tag_to_use = tag_for_lowest_seq_nr; 1082 } else { 1083 // should not happen 1084 return; 1085 } 1086 // store ccc tag 1087 entry.seq_nr = highest_seq_nr + 1u; 1088 entry.device_index = le_device_index; 1089 entry.att_handle = att_handle; 1090 entry.value = (uint8_t) value; 1091 int result = tlv_impl->store_tag(tlv_context, tag_to_use, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1092 if (result != 0){ 1093 log_error("Store tag index %u failed", index); 1094 } 1095 } 1096 1097 static void att_server_persistent_ccc_clear(att_server_t * att_server){ 1098 int le_device_index = att_server->ir_le_device_db_index; 1099 log_info("Clear CCC values of remote %s, le device id %d", bd_addr_to_str(att_server->peer_address), le_device_index); 1100 // check if bonded 1101 if (le_device_index < 0) return; 1102 // get btstack_tlv 1103 const btstack_tlv_t * tlv_impl = NULL; 1104 void * tlv_context; 1105 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1106 if (!tlv_impl) return; 1107 // get all ccc tag 1108 int index; 1109 persistent_ccc_entry_t entry; 1110 for (index=0;index<NVN_NUM_GATT_SERVER_CCC;index++){ 1111 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1112 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1113 if (len != sizeof(persistent_ccc_entry_t)) continue; 1114 if (entry.device_index != le_device_index) continue; 1115 // delete entry 1116 log_info("CCC Index %u: Delete", index); 1117 tlv_impl->delete_tag(tlv_context, tag); 1118 } 1119 } 1120 1121 static void att_server_persistent_ccc_restore(att_server_t * att_server, att_connection_t * att_connection){ 1122 int le_device_index = att_server->ir_le_device_db_index; 1123 log_info("Restore CCC values of remote %s, le device id %d", bd_addr_to_str(att_server->peer_address), le_device_index); 1124 // check if bonded 1125 if (le_device_index < 0) return; 1126 // get btstack_tlv 1127 const btstack_tlv_t * tlv_impl = NULL; 1128 void * tlv_context; 1129 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1130 if (!tlv_impl) return; 1131 // get all ccc tag 1132 int index; 1133 persistent_ccc_entry_t entry; 1134 for (index=0;index<NVN_NUM_GATT_SERVER_CCC;index++){ 1135 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1136 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1137 if (len != sizeof(persistent_ccc_entry_t)) continue; 1138 if (entry.device_index != le_device_index) continue; 1139 // simulate write callback 1140 uint16_t attribute_handle = entry.att_handle; 1141 uint8_t value[2]; 1142 little_endian_store_16(value, 0, entry.value); 1143 att_write_callback_t callback = att_server_write_callback_for_handle(attribute_handle); 1144 if (!callback) continue; 1145 log_info("CCC Index %u: Set Attribute handle 0x%04x to value 0x%04x", index, attribute_handle, entry.value ); 1146 (*callback)(att_connection->con_handle, attribute_handle, ATT_TRANSACTION_MODE_NONE, 0, value, sizeof(value)); 1147 } 1148 } 1149 1150 // persistent CCC writes 1151 // --------------------- 1152 1153 // gatt service management 1154 static att_service_handler_t * att_service_handler_for_handle(uint16_t handle){ 1155 btstack_linked_list_iterator_t it; 1156 btstack_linked_list_iterator_init(&it, &service_handlers); 1157 while (btstack_linked_list_iterator_has_next(&it)){ 1158 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1159 if (handler->start_handle > handle) continue; 1160 if (handler->end_handle < handle) continue; 1161 return handler; 1162 } 1163 return NULL; 1164 } 1165 static att_read_callback_t att_server_read_callback_for_handle(uint16_t handle){ 1166 att_service_handler_t * handler = att_service_handler_for_handle(handle); 1167 if (handler != NULL) return handler->read_callback; 1168 return att_server_client_read_callback; 1169 } 1170 1171 static att_write_callback_t att_server_write_callback_for_handle(uint16_t handle){ 1172 att_service_handler_t * handler = att_service_handler_for_handle(handle); 1173 if (handler != NULL) return handler->write_callback; 1174 return att_server_client_write_callback; 1175 } 1176 1177 static btstack_packet_handler_t att_server_packet_handler_for_handle(uint16_t handle){ 1178 att_service_handler_t * handler = att_service_handler_for_handle(handle); 1179 if (handler != NULL) return handler->packet_handler; 1180 return att_client_packet_handler; 1181 } 1182 1183 static void att_notify_write_callbacks(hci_con_handle_t con_handle, uint16_t transaction_mode){ 1184 // notify all callbacks 1185 btstack_linked_list_iterator_t it; 1186 btstack_linked_list_iterator_init(&it, &service_handlers); 1187 while (btstack_linked_list_iterator_has_next(&it)){ 1188 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1189 if (!handler->write_callback) continue; 1190 (*handler->write_callback)(con_handle, 0, transaction_mode, 0, NULL, 0); 1191 } 1192 if (!att_server_client_write_callback) return; 1193 (*att_server_client_write_callback)(con_handle, 0, transaction_mode, 0, NULL, 0); 1194 } 1195 1196 // returns first reported error or 0 1197 static uint8_t att_validate_prepared_write(hci_con_handle_t con_handle){ 1198 btstack_linked_list_iterator_t it; 1199 btstack_linked_list_iterator_init(&it, &service_handlers); 1200 while (btstack_linked_list_iterator_has_next(&it)){ 1201 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1202 if (!handler->write_callback) continue; 1203 uint8_t error_code = (*handler->write_callback)(con_handle, 0, ATT_TRANSACTION_MODE_VALIDATE, 0, NULL, 0); 1204 if (error_code != 0u) return error_code; 1205 } 1206 if (!att_server_client_write_callback) return 0; 1207 return (*att_server_client_write_callback)(con_handle, 0, ATT_TRANSACTION_MODE_VALIDATE, 0, NULL, 0); 1208 } 1209 1210 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){ 1211 att_read_callback_t callback = att_server_read_callback_for_handle(attribute_handle); 1212 if (!callback) return 0; 1213 return (*callback)(con_handle, attribute_handle, offset, buffer, buffer_size); 1214 } 1215 1216 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){ 1217 switch (transaction_mode){ 1218 case ATT_TRANSACTION_MODE_VALIDATE: 1219 return att_validate_prepared_write(con_handle); 1220 case ATT_TRANSACTION_MODE_EXECUTE: 1221 case ATT_TRANSACTION_MODE_CANCEL: 1222 att_notify_write_callbacks(con_handle, transaction_mode); 1223 return 0; 1224 default: 1225 break; 1226 } 1227 1228 // track CCC writes 1229 if (att_is_persistent_ccc(attribute_handle) && (offset == 0u) && (buffer_size == 2u)){ 1230 att_server_persistent_ccc_write(con_handle, attribute_handle, little_endian_read_16(buffer, 0)); 1231 } 1232 1233 att_write_callback_t callback = att_server_write_callback_for_handle(attribute_handle); 1234 if (!callback) return 0; 1235 return (*callback)(con_handle, attribute_handle, transaction_mode, offset, buffer, buffer_size); 1236 } 1237 1238 /** 1239 * @brief register read/write callbacks for specific handle range 1240 * @param att_service_handler_t 1241 */ 1242 void att_server_register_service_handler(att_service_handler_t * handler){ 1243 bool att_server_registered = false; 1244 if (att_service_handler_for_handle(handler->start_handle)){ 1245 att_server_registered = true; 1246 } 1247 1248 if (att_service_handler_for_handle(handler->end_handle)){ 1249 att_server_registered = true; 1250 } 1251 1252 if (att_server_registered){ 1253 log_error("handler for range 0x%04x-0x%04x already registered", handler->start_handle, handler->end_handle); 1254 return; 1255 } 1256 btstack_linked_list_add(&service_handlers, (btstack_linked_item_t*) handler); 1257 } 1258 1259 void att_server_init(uint8_t const * db, att_read_callback_t read_callback, att_write_callback_t write_callback){ 1260 1261 // store callbacks 1262 att_server_client_read_callback = read_callback; 1263 att_server_client_write_callback = write_callback; 1264 1265 // register for HCI Events 1266 hci_event_callback_registration.callback = &att_server_event_packet_handler; 1267 hci_add_event_handler(&hci_event_callback_registration); 1268 1269 // register for SM events 1270 sm_event_callback_registration.callback = &att_server_event_packet_handler; 1271 sm_add_event_handler(&sm_event_callback_registration); 1272 1273 // and L2CAP ATT Server PDUs 1274 att_dispatch_register_server(att_server_dispatch_packet_handler); 1275 1276 #ifdef ENABLE_GATT_OVER_CLASSIC 1277 // setup l2cap service 1278 att_dispatch_classic_register_service(); 1279 #endif 1280 1281 att_set_db(db); 1282 att_set_read_callback(att_server_read_callback); 1283 att_set_write_callback(att_server_write_callback); 1284 } 1285 1286 void att_server_register_packet_handler(btstack_packet_handler_t handler){ 1287 att_client_packet_handler = handler; 1288 } 1289 1290 1291 // to be deprecated 1292 int att_server_can_send_packet_now(hci_con_handle_t con_handle){ 1293 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1294 if (!hci_connection) return 0; 1295 att_server_t * att_server = &hci_connection->att_server; 1296 att_connection_t * att_connection = &hci_connection->att_connection; 1297 return att_server_can_send_packet(att_server, att_connection); 1298 } 1299 1300 uint8_t att_server_register_can_send_now_callback(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1301 return att_server_request_to_send_notification(callback_registration, con_handle); 1302 } 1303 1304 void att_server_request_can_send_now_event(hci_con_handle_t con_handle){ 1305 att_client_waiting_for_can_send_registration.callback = &att_emit_can_send_now_event; 1306 att_server_request_to_send_notification(&att_client_waiting_for_can_send_registration, con_handle); 1307 } 1308 // end of deprecated 1309 1310 uint8_t att_server_request_to_send_notification(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1311 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1312 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1313 att_server_t * att_server = &hci_connection->att_server; 1314 att_connection_t * att_connection = &hci_connection->att_connection; 1315 bool added = btstack_linked_list_add_tail(&att_server->notification_requests, (btstack_linked_item_t*) callback_registration); 1316 att_server_request_can_send_now(att_server, att_connection); 1317 if (added){ 1318 return ERROR_CODE_SUCCESS; 1319 } else { 1320 return ERROR_CODE_COMMAND_DISALLOWED; 1321 } 1322 } 1323 1324 uint8_t att_server_request_to_send_indication(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1325 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1326 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1327 att_server_t * att_server = &hci_connection->att_server; 1328 att_connection_t * att_connection = &hci_connection->att_connection; 1329 bool added = btstack_linked_list_add_tail(&att_server->indication_requests, (btstack_linked_item_t*) callback_registration); 1330 att_server_request_can_send_now(att_server, att_connection); 1331 if (added){ 1332 return ERROR_CODE_SUCCESS; 1333 } else { 1334 return ERROR_CODE_COMMAND_DISALLOWED; 1335 } 1336 } 1337 1338 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){ 1339 1340 att_server_t * att_server = NULL; 1341 att_connection_t * att_connection = NULL; 1342 uint8_t * packet_buffer = NULL; 1343 1344 // prefer enhanced bearer 1345 #ifdef ENABLE_GATT_OVER_EATT 1346 att_server_eatt_bearer_t * eatt_bearer = att_server_eatt_bearer_for_con_handle(con_handle); 1347 if (eatt_bearer != NULL){ 1348 att_server = &eatt_bearer->att_server; 1349 att_connection = &eatt_bearer->att_connection; 1350 packet_buffer = eatt_bearer->send_buffer; 1351 } else 1352 #endif 1353 { 1354 hci_connection_t *hci_connection = hci_connection_for_handle(con_handle); 1355 if (hci_connection != NULL) { 1356 att_server = &hci_connection->att_server; 1357 att_connection = &hci_connection->att_connection; 1358 } 1359 } 1360 1361 if (att_server == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1362 if (!att_server_can_send_packet(att_server, att_connection)) return BTSTACK_ACL_BUFFERS_FULL; 1363 1364 if (packet_buffer == NULL){ 1365 l2cap_reserve_packet_buffer(); 1366 packet_buffer = l2cap_get_outgoing_buffer(); 1367 } 1368 1369 *out_att_connection = att_connection; 1370 *out_att_server = att_server; 1371 *out_packet_buffer = packet_buffer; 1372 return ERROR_CODE_SUCCESS; 1373 } 1374 1375 uint8_t att_server_notify(hci_con_handle_t con_handle, uint16_t attribute_handle, const uint8_t *value, uint16_t value_len){ 1376 att_server_t * att_server = NULL; 1377 att_connection_t * att_connection = NULL; 1378 uint8_t * packet_buffer = NULL; 1379 1380 uint8_t status = att_server_prepare_server_message(con_handle, &att_server, &att_connection, &packet_buffer); 1381 if (status != ERROR_CODE_SUCCESS){ 1382 return status; 1383 } 1384 1385 uint16_t size = att_prepare_handle_value_notification(att_connection, attribute_handle, value, value_len, packet_buffer); 1386 1387 return att_server_send_prepared(att_server, att_connection, NULL, size); 1388 } 1389 1390 /** 1391 * @brief notify client about multiple attribute value changes 1392 * @param con_handle 1393 * @param num_attributes 1394 * @param attribute_handles[] 1395 * @param values_data[] 1396 * @param values_len[] 1397 * @return 0 if ok, error otherwise 1398 */ 1399 uint8_t att_server_multiple_notify(hci_con_handle_t con_handle, uint8_t num_attributes, 1400 const uint16_t * attribute_handles, const uint8_t ** values_data, const uint16_t * values_len){ 1401 1402 att_server_t * att_server = NULL; 1403 att_connection_t * att_connection = NULL; 1404 uint8_t * packet_buffer = NULL; 1405 1406 uint8_t status = att_server_prepare_server_message(con_handle, &att_server, &att_connection, &packet_buffer); 1407 if (status != ERROR_CODE_SUCCESS){ 1408 return status; 1409 } 1410 1411 uint16_t size = att_prepare_handle_value_multiple_notification(att_connection, num_attributes, attribute_handles, values_data, values_len, packet_buffer); 1412 1413 return att_server_send_prepared(att_server, att_connection, packet_buffer, size); 1414 } 1415 1416 uint8_t att_server_indicate(hci_con_handle_t con_handle, uint16_t attribute_handle, const uint8_t *value, uint16_t value_len){ 1417 1418 att_server_t * att_server = NULL; 1419 att_connection_t * att_connection = NULL; 1420 uint8_t * packet_buffer = NULL; 1421 1422 uint8_t status = att_server_prepare_server_message(con_handle, &att_server, &att_connection, &packet_buffer); 1423 if (status != ERROR_CODE_SUCCESS){ 1424 return status; 1425 } 1426 1427 if (att_server->value_indication_handle != 0u) { 1428 // free reserved packet buffer 1429 if (att_server->bearer_type == ATT_BEARER_ENHANCED_LE){ 1430 l2cap_release_packet_buffer(); 1431 } 1432 return ATT_HANDLE_VALUE_INDICATION_IN_PROGRESS; 1433 } 1434 1435 // track indication 1436 att_server->value_indication_handle = attribute_handle; 1437 btstack_run_loop_set_timer_handler(&att_server->value_indication_timer, att_handle_value_indication_timeout); 1438 btstack_run_loop_set_timer(&att_server->value_indication_timer, ATT_TRANSACTION_TIMEOUT_MS); 1439 btstack_run_loop_add_timer(&att_server->value_indication_timer); 1440 1441 uint16_t size = att_prepare_handle_value_indication(att_connection, attribute_handle, value, value_len, packet_buffer); 1442 1443 return att_server_send_prepared(att_server, att_connection, NULL, size); 1444 } 1445 1446 uint16_t att_server_get_mtu(hci_con_handle_t con_handle){ 1447 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1448 if (!hci_connection) return 0; 1449 att_connection_t * att_connection = &hci_connection->att_connection; 1450 return att_connection->mtu; 1451 } 1452 1453 void att_server_deinit(void){ 1454 att_server_client_read_callback = NULL; 1455 att_server_client_write_callback = NULL; 1456 att_client_packet_handler = NULL; 1457 service_handlers = NULL; 1458 } 1459 1460 #ifdef ENABLE_GATT_OVER_EATT 1461 1462 #define MAX_NR_EATT_CHANNELS 5 1463 1464 static uint16_t att_server_eatt_receive_buffer_size; 1465 static uint16_t att_server_eatt_send_buffer_size; 1466 1467 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_cid(uint16_t cid){ 1468 btstack_linked_list_iterator_t it; 1469 btstack_linked_list_iterator_init(&it, &att_server_eatt_bearer_active); 1470 while(btstack_linked_list_iterator_has_next(&it)){ 1471 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) btstack_linked_list_iterator_next(&it); 1472 if (eatt_bearer->att_server.l2cap_cid == cid) { 1473 return eatt_bearer; 1474 } 1475 } 1476 return NULL; 1477 } 1478 1479 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_con_handle(hci_con_handle_t con_handle){ 1480 btstack_linked_list_iterator_t it; 1481 btstack_linked_list_iterator_init(&it, &att_server_eatt_bearer_active); 1482 while(btstack_linked_list_iterator_has_next(&it)){ 1483 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) btstack_linked_list_iterator_next(&it); 1484 if (eatt_bearer->att_connection.con_handle == con_handle) { 1485 return eatt_bearer; 1486 } 1487 } 1488 return NULL; 1489 } 1490 1491 static void att_server_eatt_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 1492 uint16_t cid; 1493 uint8_t status; 1494 uint16_t remote_mtu; 1495 1496 uint8_t i; 1497 uint8_t num_requested_bearers; 1498 uint8_t num_accepted_bearers; 1499 uint16_t initial_credits = L2CAP_LE_AUTOMATIC_CREDITS; 1500 uint8_t * receive_buffers[MAX_NR_EATT_CHANNELS]; 1501 uint16_t cids[MAX_NR_EATT_CHANNELS]; 1502 att_server_eatt_bearer_t * eatt_bearers[MAX_NR_EATT_CHANNELS]; 1503 att_server_eatt_bearer_t * eatt_bearer; 1504 att_server_t * att_server; 1505 att_connection_t * att_connection; 1506 hci_con_handle_t con_handle; 1507 hci_connection_t * hci_connection; 1508 1509 switch (packet_type) { 1510 1511 case L2CAP_DATA_PACKET: 1512 eatt_bearer = att_server_eatt_bearer_for_cid(channel); 1513 btstack_assert(eatt_bearer != NULL); 1514 att_server = &eatt_bearer->att_server; 1515 att_connection = &eatt_bearer->att_connection; 1516 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1517 break; 1518 1519 case HCI_EVENT_PACKET: 1520 switch (packet[0]) { 1521 1522 case L2CAP_EVENT_CAN_SEND_NOW: 1523 cid = l2cap_event_packet_sent_get_local_cid(packet); 1524 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1525 btstack_assert(eatt_bearer != NULL); 1526 att_server = &eatt_bearer->att_server; 1527 att_connection = &eatt_bearer->att_connection; 1528 // only used for EATT request responses 1529 btstack_assert(att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED); 1530 att_server_process_validated_request(att_server, att_connection, eatt_bearer->send_buffer); 1531 break; 1532 1533 case L2CAP_EVENT_PACKET_SENT: 1534 cid = l2cap_event_packet_sent_get_local_cid(packet); 1535 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1536 btstack_assert(eatt_bearer != NULL); 1537 att_server = &eatt_bearer->att_server; 1538 att_connection = &eatt_bearer->att_connection; 1539 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1540 break; 1541 1542 case L2CAP_EVENT_ECBM_INCOMING_CONNECTION: 1543 cid = l2cap_event_ecbm_incoming_connection_get_local_cid(packet); 1544 1545 // reject if outgoing l2cap connection active, L2CAP/TIM/BV-01-C 1546 con_handle = l2cap_event_ecbm_incoming_connection_get_handle(packet); 1547 hci_connection = hci_connection_for_handle(con_handle); 1548 btstack_assert(hci_connection != NULL); 1549 if (hci_connection->att_server.eatt_outgoing_active) { 1550 hci_connection->att_server.incoming_connection_request = true; 1551 l2cap_ecbm_decline_channels(cid, L2CAP_ECBM_CONNECTION_RESULT_SOME_REFUSED_INSUFFICIENT_RESOURCES_AVAILABLE ); 1552 log_info("Decline incoming connection from %s", bd_addr_to_str(hci_connection->address)); 1553 } else { 1554 num_requested_bearers = l2cap_event_ecbm_incoming_connection_get_num_channels(packet); 1555 for (i = 0; i < num_requested_bearers; i++){ 1556 eatt_bearers[i] = (att_server_eatt_bearer_t *) btstack_linked_list_pop(&att_server_eatt_bearer_pool); 1557 if (eatt_bearers[i] == NULL) { 1558 break; 1559 } 1560 eatt_bearers[i]->att_connection.con_handle = l2cap_event_ecbm_incoming_connection_get_handle(packet); 1561 eatt_bearers[i]->att_server.bearer_type = ATT_BEARER_ENHANCED_LE; 1562 receive_buffers[i] = eatt_bearers[i]->receive_buffer; 1563 btstack_linked_list_add(&att_server_eatt_bearer_active, (btstack_linked_item_t *) eatt_bearers[i]); 1564 } 1565 num_accepted_bearers = i; 1566 status = l2cap_ecbm_accept_channels(cid, num_accepted_bearers, initial_credits, att_server_eatt_receive_buffer_size, receive_buffers, cids); 1567 btstack_assert(status == ERROR_CODE_SUCCESS); 1568 log_info("requested %u, accepted %u", num_requested_bearers, num_accepted_bearers); 1569 for (i=0;i<num_accepted_bearers;i++){ 1570 log_info("eatt l2cap cid: 0x%04x", cids[i]); 1571 eatt_bearers[i]->att_server.l2cap_cid = cids[i]; 1572 } 1573 } 1574 break; 1575 1576 case L2CAP_EVENT_ECBM_CHANNEL_OPENED: 1577 cid = l2cap_event_ecbm_channel_opened_get_local_cid(packet); 1578 status = l2cap_event_ecbm_channel_opened_get_status(packet); 1579 remote_mtu = l2cap_event_ecbm_channel_opened_get_remote_mtu(packet); 1580 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1581 btstack_assert(eatt_bearer != NULL); 1582 eatt_bearer->att_connection.mtu_exchanged = true; 1583 eatt_bearer->att_connection.mtu = remote_mtu; 1584 eatt_bearer->att_connection.max_mtu = remote_mtu; 1585 log_info("L2CAP_EVENT_ECBM_CHANNEL_OPENED - cid 0x%04x mtu %u, status 0x%02x", cid, remote_mtu, status); 1586 break; 1587 1588 case L2CAP_EVENT_ECBM_RECONFIGURED: 1589 break; 1590 1591 case L2CAP_EVENT_CHANNEL_CLOSED: 1592 eatt_bearer = att_server_eatt_bearer_for_cid(l2cap_event_channel_closed_get_local_cid(packet)); 1593 btstack_assert(eatt_bearers != NULL); 1594 1595 // TODO: finalize - abort queued writes 1596 1597 btstack_linked_list_remove(&att_server_eatt_bearer_active, (btstack_linked_item_t *) eatt_bearer); 1598 btstack_linked_list_add(&att_server_eatt_bearer_pool, (btstack_linked_item_t *) eatt_bearer); 1599 break; 1600 default: 1601 break; 1602 } 1603 break; 1604 default: 1605 btstack_unreachable(); 1606 break; 1607 } 1608 } 1609 1610 // create eatt bearers 1611 uint8_t att_server_eatt_init(uint8_t num_eatt_bearers, uint8_t * storage_buffer, uint16_t storage_size){ 1612 uint16_t size_for_structs = num_eatt_bearers * sizeof(att_server_eatt_bearer_t); 1613 if (storage_size < size_for_structs) { 1614 return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED; 1615 } 1616 1617 // TODO: The minimum ATT_MTU for an Enhanced ATT bearer is 64 octets. 1618 1619 memset(storage_buffer, 0, storage_size); 1620 uint16_t buffer_size_per_bearer = ((storage_size - size_for_structs) / num_eatt_bearers); 1621 att_server_eatt_receive_buffer_size = buffer_size_per_bearer / 2; 1622 att_server_eatt_send_buffer_size = buffer_size_per_bearer / 2; 1623 uint8_t * bearer_buffer = &storage_buffer[size_for_structs]; 1624 uint8_t i; 1625 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) storage_buffer; 1626 log_info("%u EATT bearers with receive buffer size %u", 1627 num_eatt_bearers, att_server_eatt_receive_buffer_size); 1628 for (i=0;i<num_eatt_bearers;i++){ 1629 eatt_bearer->att_connection.con_handle = HCI_CON_HANDLE_INVALID; 1630 eatt_bearer->receive_buffer = bearer_buffer; 1631 bearer_buffer += att_server_eatt_receive_buffer_size; 1632 eatt_bearer->send_buffer = bearer_buffer; 1633 bearer_buffer += att_server_eatt_send_buffer_size; 1634 btstack_linked_list_add(&att_server_eatt_bearer_pool, (btstack_linked_item_t *) eatt_bearer); 1635 eatt_bearer++; 1636 } 1637 // TODO: define minimum EATT MTU 1638 l2cap_ecbm_register_service(att_server_eatt_handler, BLUETOOTH_PSM_EATT, 64, 0, false); 1639 1640 return 0; 1641 } 1642 #endif