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 MATTHIAS 24 * RINGWALD 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_db.c" 39 40 #include <string.h> 41 42 #include "ble/att_db.h" 43 #include "ble/core.h" 44 #include "bluetooth.h" 45 #include "btstack_debug.h" 46 #include "btstack_util.h" 47 48 // check for ENABLE_ATT_DELAYED_READ_RESPONSE -> ENABLE_ATT_DELAYED_RESPONSE, 49 #ifdef ENABLE_ATT_DELAYED_READ_RESPONSE 50 #error "ENABLE_ATT_DELAYED_READ_RESPONSE was replaced by ENABLE_ATT_DELAYED_RESPONSE. Please update btstack_config.h" 51 #endif 52 53 typedef enum { 54 ATT_READ, 55 ATT_WRITE, 56 } att_operation_t; 57 58 59 static int is_Bluetooth_Base_UUID(uint8_t const *uuid){ 60 // Bluetooth Base UUID 00000000-0000-1000-8000-00805F9B34FB in little endian 61 static const uint8_t bluetooth_base_uuid[] = { 0xfb, 0x34, 0x9b, 0x5f, 0x80, 0x00, 0x00, 0x80, 0x00, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 62 63 if (memcmp(&uuid[0], &bluetooth_base_uuid[0], 12) != 0) return false; 64 if (memcmp(&uuid[14], &bluetooth_base_uuid[14], 2) != 0) return false; 65 return true; 66 67 } 68 69 static uint16_t uuid16_from_uuid(uint16_t uuid_len, uint8_t * uuid){ 70 if (uuid_len == 2) return little_endian_read_16(uuid, 0); 71 if (!is_Bluetooth_Base_UUID(uuid)) return 0; 72 return little_endian_read_16(uuid, 12); 73 } 74 75 // ATT Database 76 77 // new java-style iterator 78 typedef struct att_iterator { 79 // private 80 uint8_t const * att_ptr; 81 // public 82 uint16_t size; 83 uint16_t flags; 84 uint16_t handle; 85 uint8_t const * uuid; 86 uint16_t value_len; 87 uint8_t const * value; 88 } att_iterator_t; 89 90 static void att_persistent_ccc_cache(att_iterator_t * it); 91 92 static uint8_t const * att_db = NULL; 93 static att_read_callback_t att_read_callback = NULL; 94 static att_write_callback_t att_write_callback = NULL; 95 static int att_prepare_write_error_code = 0; 96 static uint16_t att_prepare_write_error_handle = 0x0000; 97 98 // single cache for att_is_persistent_ccc - stores flags before write callback 99 static uint16_t att_persistent_ccc_handle; 100 static uint16_t att_persistent_ccc_uuid16; 101 102 static void att_iterator_init(att_iterator_t *it){ 103 it->att_ptr = att_db; 104 } 105 106 static bool att_iterator_has_next(att_iterator_t *it){ 107 return it->att_ptr != NULL; 108 } 109 110 static void att_iterator_fetch_next(att_iterator_t *it){ 111 it->size = little_endian_read_16(it->att_ptr, 0); 112 if (it->size == 0){ 113 it->flags = 0; 114 it->handle = 0; 115 it->uuid = NULL; 116 it->value_len = 0; 117 it->value = NULL; 118 it->att_ptr = NULL; 119 return; 120 } 121 it->flags = little_endian_read_16(it->att_ptr, 2); 122 it->handle = little_endian_read_16(it->att_ptr, 4); 123 it->uuid = &it->att_ptr[6]; 124 // handle 128 bit UUIDs 125 if ((it->flags & ATT_PROPERTY_UUID128) != 0){ 126 it->value_len = it->size - 22; 127 it->value = &it->att_ptr[22]; 128 } else { 129 it->value_len = it->size - 8; 130 it->value = &it->att_ptr[8]; 131 } 132 // advance AFTER setting values 133 it->att_ptr += it->size; 134 } 135 136 static int att_iterator_match_uuid16(att_iterator_t *it, uint16_t uuid){ 137 if (it->handle == 0) return 0; 138 if (it->flags & ATT_PROPERTY_UUID128){ 139 if (!is_Bluetooth_Base_UUID(it->uuid)) return 0; 140 return little_endian_read_16(it->uuid, 12) == uuid; 141 } 142 return little_endian_read_16(it->uuid, 0) == uuid; 143 } 144 145 static int att_iterator_match_uuid(att_iterator_t *it, uint8_t *uuid, uint16_t uuid_len){ 146 if (it->handle == 0) return 0; 147 // input: UUID16 148 if (uuid_len == 2) { 149 return att_iterator_match_uuid16(it, little_endian_read_16(uuid, 0)); 150 } 151 // input and db: UUID128 152 if ((it->flags & ATT_PROPERTY_UUID128) != 0){ 153 return memcmp(it->uuid, uuid, 16) == 0; 154 } 155 // input: UUID128, db: UUID16 156 if (!is_Bluetooth_Base_UUID(uuid)) return 0; 157 return little_endian_read_16(uuid, 12) == little_endian_read_16(it->uuid, 0); 158 } 159 160 161 static int att_find_handle(att_iterator_t *it, uint16_t handle){ 162 if (handle == 0) return 0; 163 att_iterator_init(it); 164 while (att_iterator_has_next(it)){ 165 att_iterator_fetch_next(it); 166 if (it->handle != handle) continue; 167 return 1; 168 } 169 return 0; 170 } 171 172 // experimental client API 173 uint16_t att_uuid_for_handle(uint16_t attribute_handle){ 174 att_iterator_t it; 175 int ok = att_find_handle(&it, attribute_handle); 176 if (!ok) return 0; 177 if ((it.flags & ATT_PROPERTY_UUID128) != 0) return 0; 178 return little_endian_read_16(it.uuid, 0); 179 } 180 // end of client API 181 182 static void att_update_value_len(att_iterator_t *it, hci_con_handle_t con_handle){ 183 if ((it->flags & ATT_PROPERTY_DYNAMIC) == 0) return; 184 it->value_len = (*att_read_callback)(con_handle, it->handle, 0, NULL, 0); 185 return; 186 } 187 188 // copy attribute value from offset into buffer with given size 189 static int att_copy_value(att_iterator_t *it, uint16_t offset, uint8_t * buffer, uint16_t buffer_size, hci_con_handle_t con_handle){ 190 191 // DYNAMIC 192 if ((it->flags & ATT_PROPERTY_DYNAMIC) != 0){ 193 return (*att_read_callback)(con_handle, it->handle, offset, buffer, buffer_size); 194 } 195 196 // STATIC 197 uint16_t bytes_to_copy = it->value_len - offset; 198 if (bytes_to_copy > buffer_size){ 199 bytes_to_copy = buffer_size; 200 } 201 (void)memcpy(buffer, it->value, bytes_to_copy); 202 return bytes_to_copy; 203 } 204 205 void att_set_db(uint8_t const * db){ 206 // validate db version 207 if (db == NULL) return; 208 if (*db++ != ATT_DB_VERSION){ 209 log_error("ATT DB version differs, please regenerate .h from .gatt file or update att_db_util.c"); 210 return; 211 } 212 att_db = db; 213 } 214 215 void att_set_read_callback(att_read_callback_t callback){ 216 att_read_callback = callback; 217 } 218 219 void att_set_write_callback(att_write_callback_t callback){ 220 att_write_callback = callback; 221 } 222 223 void att_dump_attributes(void){ 224 att_iterator_t it; 225 att_iterator_init(&it); 226 uint8_t uuid128[16]; 227 while (att_iterator_has_next(&it)){ 228 att_iterator_fetch_next(&it); 229 if (it.handle == 0) { 230 log_info("Handle: END"); 231 return; 232 } 233 log_info("Handle: 0x%04x, flags: 0x%04x, uuid: ", it.handle, it.flags); 234 if ((it.flags & ATT_PROPERTY_UUID128) != 0){ 235 reverse_128(it.uuid, uuid128); 236 log_info("%s", uuid128_to_str(uuid128)); 237 } else { 238 log_info("%04x", little_endian_read_16(it.uuid, 0)); 239 } 240 log_info(", value_len: %u, value: ", it.value_len); 241 log_info_hexdump(it.value, it.value_len); 242 } 243 } 244 245 static void att_prepare_write_reset(void){ 246 att_prepare_write_error_code = 0; 247 att_prepare_write_error_handle = 0x0000; 248 } 249 250 static void att_prepare_write_update_errors(uint8_t error_code, uint16_t handle){ 251 // first ATT_ERROR_INVALID_ATTRIBUTE_VALUE_LENGTH has highest priority 252 if ((error_code == ATT_ERROR_INVALID_ATTRIBUTE_VALUE_LENGTH) && (error_code != att_prepare_write_error_code)){ 253 att_prepare_write_error_code = error_code; 254 att_prepare_write_error_handle = handle; 255 return; 256 } 257 // first ATT_ERROR_INVALID_OFFSET is next 258 if ((error_code == ATT_ERROR_INVALID_OFFSET) && (att_prepare_write_error_code == 0)){ 259 att_prepare_write_error_code = error_code; 260 att_prepare_write_error_handle = handle; 261 return; 262 } 263 } 264 265 static uint16_t setup_error(uint8_t * response_buffer, uint16_t request, uint16_t handle, uint8_t error_code){ 266 response_buffer[0] = ATT_ERROR_RESPONSE; 267 response_buffer[1] = request; 268 little_endian_store_16(response_buffer, 2, handle); 269 response_buffer[4] = error_code; 270 return 5; 271 } 272 273 static inline uint16_t setup_error_read_not_permitted(uint8_t * response_buffer, uint16_t request, uint16_t start_handle){ 274 return setup_error(response_buffer, request, start_handle, ATT_ERROR_READ_NOT_PERMITTED); 275 } 276 277 static inline uint16_t setup_error_write_not_permitted(uint8_t * response_buffer, uint16_t request, uint16_t start_handle){ 278 return setup_error(response_buffer, request, start_handle, ATT_ERROR_WRITE_NOT_PERMITTED); 279 } 280 281 static inline uint16_t setup_error_atribute_not_found(uint8_t * response_buffer, uint16_t request, uint16_t start_handle){ 282 return setup_error(response_buffer, request, start_handle, ATT_ERROR_ATTRIBUTE_NOT_FOUND); 283 } 284 285 static inline uint16_t setup_error_invalid_handle(uint8_t * response_buffer, uint16_t request, uint16_t handle){ 286 return setup_error(response_buffer, request, handle, ATT_ERROR_INVALID_HANDLE); 287 } 288 289 static inline uint16_t setup_error_invalid_offset(uint8_t * response_buffer, uint16_t request, uint16_t handle){ 290 return setup_error(response_buffer, request, handle, ATT_ERROR_INVALID_OFFSET); 291 } 292 293 static inline uint16_t setup_error_invalid_pdu(uint8_t *response_buffer, uint16_t request) { 294 return setup_error(response_buffer, request, 0, ATT_ERROR_INVALID_PDU); 295 } 296 297 static uint8_t att_validate_security(att_connection_t * att_connection, att_operation_t operation, att_iterator_t * it){ 298 int required_security_level = 0; 299 int requires_secure_connection = 0; 300 switch (operation){ 301 case ATT_READ: 302 if ((it->flags & ATT_PROPERTY_READ_PERMISSION_BIT_0) != 0){ 303 required_security_level |= 1; 304 } 305 if ((it->flags & ATT_PROPERTY_READ_PERMISSION_BIT_1) != 0){ 306 required_security_level |= 2; 307 } 308 if ((it->flags & ATT_PROPERTY_READ_PERMISSION_SC) != 0){ 309 requires_secure_connection = 1; 310 } 311 break; 312 case ATT_WRITE: 313 if ((it->flags & ATT_PROPERTY_WRITE_PERMISSION_BIT_0) != 0){ 314 required_security_level |= 1; 315 } 316 if ((it->flags & ATT_PROPERTY_WRITE_PERMISSION_BIT_1) != 0){ 317 required_security_level |= 2; 318 } 319 if ((it->flags & ATT_PROPERTY_WRITE_PERMISSION_SC) != 0){ 320 requires_secure_connection = 1; 321 } 322 break; 323 } 324 325 int required_encryption_size = it->flags >> 12; 326 if (required_encryption_size != 0) required_encryption_size++; // store -1 to fit into 4 bit 327 328 log_debug("att_validate_security. flags 0x%04x (=> security level %u, key size %u) authorized %u, authenticated %u, encryption_key_size %u, secure connection %u", 329 it->flags, required_security_level, required_encryption_size, att_connection->authorized, att_connection->authenticated, att_connection->encryption_key_size, att_connection->secure_connection); 330 331 int sc_missing = requires_secure_connection && (att_connection->secure_connection == 0); 332 switch (required_security_level){ 333 case ATT_SECURITY_AUTHORIZED: 334 if ((att_connection->authorized == 0) || sc_missing){ 335 return ATT_ERROR_INSUFFICIENT_AUTHORIZATION; 336 } 337 /* fall through */ 338 case ATT_SECURITY_AUTHENTICATED: 339 if ((att_connection->authenticated == 0) || sc_missing){ 340 return ATT_ERROR_INSUFFICIENT_AUTHENTICATION; 341 } 342 /* fall through */ 343 case ATT_SECURITY_ENCRYPTED: 344 if ((required_encryption_size > 0) && ((att_connection->encryption_key_size == 0) || sc_missing)){ 345 return ATT_ERROR_INSUFFICIENT_ENCRYPTION; 346 } 347 if (required_encryption_size > att_connection->encryption_key_size){ 348 return ATT_ERROR_INSUFFICIENT_ENCRYPTION_KEY_SIZE; 349 } 350 break; 351 default: 352 break; 353 } 354 return ATT_ERROR_SUCCESS; 355 } 356 357 // 358 // MARK: ATT_EXCHANGE_MTU_REQUEST 359 // 360 static uint16_t handle_exchange_mtu_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 361 uint8_t * response_buffer){ 362 363 if (request_len != 3) return setup_error_invalid_pdu(response_buffer, ATT_EXCHANGE_MTU_REQUEST); 364 365 uint16_t client_rx_mtu = little_endian_read_16(request_buffer, 1); 366 367 // find min(local max mtu, remote mtu) >= ATT_DEFAULT_MTU and use as mtu for this connection 368 uint16_t min_mtu = btstack_min(client_rx_mtu, att_connection->max_mtu); 369 uint16_t new_mtu = btstack_max(ATT_DEFAULT_MTU, min_mtu); 370 att_connection->mtu = new_mtu; 371 372 response_buffer[0] = ATT_EXCHANGE_MTU_RESPONSE; 373 little_endian_store_16(response_buffer, 1, att_connection->mtu); 374 return 3; 375 } 376 377 378 // 379 // MARK: ATT_FIND_INFORMATION_REQUEST 380 // 381 // TODO: handle other types then GATT_PRIMARY_SERVICE_UUID and GATT_SECONDARY_SERVICE_UUID 382 // 383 static uint16_t handle_find_information_request2(att_connection_t * att_connection, uint8_t * response_buffer, uint16_t response_buffer_size, 384 uint16_t start_handle, uint16_t end_handle){ 385 386 UNUSED(att_connection); 387 388 log_info("ATT_FIND_INFORMATION_REQUEST: from %04X to %04X", start_handle, end_handle); 389 uint8_t request_type = ATT_FIND_INFORMATION_REQUEST; 390 391 if ((start_handle > end_handle) || (start_handle == 0)){ 392 return setup_error_invalid_handle(response_buffer, request_type, start_handle); 393 } 394 395 uint16_t offset = 1; 396 uint16_t uuid_len = 0; 397 398 att_iterator_t it; 399 att_iterator_init(&it); 400 while (att_iterator_has_next(&it)){ 401 att_iterator_fetch_next(&it); 402 if (!it.handle) break; 403 if (it.handle > end_handle) break; 404 if (it.handle < start_handle) continue; 405 406 // log_info("Handle 0x%04x", it.handle); 407 408 uint16_t this_uuid_len = (it.flags & ATT_PROPERTY_UUID128) ? 16 : 2; 409 410 // check if value has same len as last one if not first result 411 if (offset > 1){ 412 if (this_uuid_len != uuid_len) { 413 break; 414 } 415 } 416 417 // first 418 if (offset == 1) { 419 uuid_len = this_uuid_len; 420 // set format field 421 response_buffer[offset] = (it.flags & ATT_PROPERTY_UUID128) ? 0x02 : 0x01; 422 offset++; 423 } 424 425 // space? 426 if ((offset + 2 + uuid_len) > response_buffer_size) break; 427 428 // store 429 little_endian_store_16(response_buffer, offset, it.handle); 430 offset += 2; 431 432 (void)memcpy(response_buffer + offset, it.uuid, uuid_len); 433 offset += uuid_len; 434 } 435 436 if (offset == 1){ 437 return setup_error_atribute_not_found(response_buffer, request_type, start_handle); 438 } 439 440 response_buffer[0] = ATT_FIND_INFORMATION_REPLY; 441 return offset; 442 } 443 444 static uint16_t handle_find_information_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 445 uint8_t * response_buffer, uint16_t response_buffer_size){ 446 447 if (request_len != 5) return setup_error_invalid_pdu(response_buffer, ATT_FIND_INFORMATION_REQUEST); 448 449 uint16_t start_handle = little_endian_read_16(request_buffer, 1); 450 uint16_t end_handle = little_endian_read_16(request_buffer, 3); 451 return handle_find_information_request2(att_connection, response_buffer, response_buffer_size, start_handle, end_handle); 452 } 453 454 // 455 // MARK: ATT_FIND_BY_TYPE_VALUE 456 // 457 // "Only attributes with attribute handles between and including the Starting Handle parameter 458 // and the Ending Handle parameter that match the requested attri- bute type and the attribute 459 // value that have sufficient permissions to allow reading will be returned" -> (1) 460 // 461 // TODO: handle other types then GATT_PRIMARY_SERVICE_UUID and GATT_SECONDARY_SERVICE_UUID 462 // 463 // NOTE: doesn't handle DYNAMIC values 464 // NOTE: only supports 16 bit UUIDs 465 // 466 static uint16_t handle_find_by_type_value_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 467 uint8_t * response_buffer, uint16_t response_buffer_size){ 468 UNUSED(att_connection); 469 470 if (request_len < 7) return setup_error_invalid_pdu(response_buffer, ATT_FIND_BY_TYPE_VALUE_REQUEST); 471 472 // parse request 473 uint16_t start_handle = little_endian_read_16(request_buffer, 1); 474 uint16_t end_handle = little_endian_read_16(request_buffer, 3); 475 uint16_t attribute_type = little_endian_read_16(request_buffer, 5); 476 const uint8_t *attribute_value = &request_buffer[7]; 477 uint16_t attribute_len = request_len - 7; 478 479 log_info("ATT_FIND_BY_TYPE_VALUE_REQUEST: from %04X to %04X, type %04X, value: ", start_handle, end_handle, attribute_type); 480 log_info_hexdump(attribute_value, attribute_len); 481 uint8_t request_type = ATT_FIND_BY_TYPE_VALUE_REQUEST; 482 483 if ((start_handle > end_handle) || (start_handle == 0)){ 484 return setup_error_invalid_handle(response_buffer, request_type, start_handle); 485 } 486 487 uint16_t offset = 1; 488 uint16_t in_group = 0; 489 uint16_t prev_handle = 0; 490 491 att_iterator_t it; 492 att_iterator_init(&it); 493 while (att_iterator_has_next(&it)){ 494 att_iterator_fetch_next(&it); 495 496 if (it.handle && (it.handle < start_handle)) continue; 497 if (it.handle > end_handle) break; // (1) 498 499 // close current tag, if within a group and a new service definition starts or we reach end of att db 500 if (in_group && 501 ((it.handle == 0) || att_iterator_match_uuid16(&it, GATT_PRIMARY_SERVICE_UUID) || att_iterator_match_uuid16(&it, GATT_SECONDARY_SERVICE_UUID))){ 502 503 log_info("End of group, handle 0x%04x", prev_handle); 504 little_endian_store_16(response_buffer, offset, prev_handle); 505 offset += 2; 506 in_group = 0; 507 508 // check if space for another handle pair available 509 if ((offset + 4) > response_buffer_size){ 510 break; 511 } 512 } 513 514 // keep track of previous handle 515 prev_handle = it.handle; 516 517 // does current attribute match 518 if (it.handle && att_iterator_match_uuid16(&it, attribute_type) && (attribute_len == it.value_len) && (memcmp(attribute_value, it.value, it.value_len) == 0)){ 519 log_info("Begin of group, handle 0x%04x", it.handle); 520 little_endian_store_16(response_buffer, offset, it.handle); 521 offset += 2; 522 in_group = 1; 523 } 524 } 525 526 if (offset == 1){ 527 return setup_error_atribute_not_found(response_buffer, request_type, start_handle); 528 } 529 530 response_buffer[0] = ATT_FIND_BY_TYPE_VALUE_RESPONSE; 531 return offset; 532 } 533 534 // 535 // MARK: ATT_READ_BY_TYPE_REQUEST 536 // 537 static uint16_t handle_read_by_type_request2(att_connection_t * att_connection, uint8_t * response_buffer, uint16_t response_buffer_size, 538 uint16_t start_handle, uint16_t end_handle, 539 uint16_t attribute_type_len, uint8_t * attribute_type){ 540 541 log_info("ATT_READ_BY_TYPE_REQUEST: from %04X to %04X, type: ", start_handle, end_handle); 542 log_info_hexdump(attribute_type, attribute_type_len); 543 uint8_t request_type = ATT_READ_BY_TYPE_REQUEST; 544 545 if ((start_handle > end_handle) || (start_handle == 0)){ 546 return setup_error_invalid_handle(response_buffer, request_type, start_handle); 547 } 548 549 uint16_t offset = 1; 550 uint16_t pair_len = 0; 551 552 att_iterator_t it; 553 att_iterator_init(&it); 554 uint8_t error_code = 0; 555 uint16_t first_matching_but_unreadable_handle = 0; 556 557 #ifdef ENABLE_ATT_DELAYED_RESPONSE 558 bool read_request_pending = false; 559 #endif 560 561 while (att_iterator_has_next(&it)){ 562 att_iterator_fetch_next(&it); 563 564 if (!it.handle) break; 565 if (it.handle < start_handle) continue; 566 if (it.handle > end_handle) break; // (1) 567 568 // does current attribute match 569 if (!att_iterator_match_uuid(&it, attribute_type, attribute_type_len)) continue; 570 571 // skip handles that cannot be read but rembember that there has been at least one 572 if ((it.flags & ATT_PROPERTY_READ) == 0) { 573 if (first_matching_but_unreadable_handle == 0) { 574 first_matching_but_unreadable_handle = it.handle; 575 } 576 continue; 577 } 578 579 // check security requirements 580 error_code = att_validate_security(att_connection, ATT_READ, &it); 581 if (error_code != 0) break; 582 583 att_update_value_len(&it, att_connection->con_handle); 584 585 #ifdef ENABLE_ATT_DELAYED_RESPONSE 586 if (it.value_len == ATT_READ_RESPONSE_PENDING){ 587 read_request_pending = true; 588 } 589 if (read_request_pending) continue; 590 #endif 591 592 // check if value has same len as last one 593 uint16_t this_pair_len = 2 + it.value_len; 594 if (offset > 1){ 595 if (pair_len != this_pair_len) { 596 break; 597 } 598 } 599 600 // first 601 if (offset == 1) { 602 pair_len = this_pair_len; 603 response_buffer[offset] = pair_len; 604 offset++; 605 } 606 607 // space? 608 if ((offset + pair_len) > response_buffer_size) { 609 if (offset > 2) break; 610 it.value_len = response_buffer_size - 4; 611 response_buffer[1] = 2 + it.value_len; 612 } 613 614 // store 615 little_endian_store_16(response_buffer, offset, it.handle); 616 offset += 2; 617 uint16_t bytes_copied = att_copy_value(&it, 0, response_buffer + offset, it.value_len, att_connection->con_handle); 618 offset += bytes_copied; 619 } 620 621 #ifdef ENABLE_ATT_DELAYED_RESPONSE 622 if (read_request_pending) return ATT_READ_RESPONSE_PENDING; 623 #endif 624 625 // at least one attribute could be read 626 if (offset > 1){ 627 response_buffer[0] = ATT_READ_BY_TYPE_RESPONSE; 628 return offset; 629 } 630 631 // first attribute had an error 632 if (error_code != 0){ 633 return setup_error(response_buffer, request_type, start_handle, error_code); 634 } 635 636 // no other errors, but all found attributes had been non-readable 637 if (first_matching_but_unreadable_handle != 0){ 638 return setup_error_read_not_permitted(response_buffer, request_type, first_matching_but_unreadable_handle); 639 } 640 641 // attribute not found 642 return setup_error_atribute_not_found(response_buffer, request_type, start_handle); 643 } 644 645 static uint16_t handle_read_by_type_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 646 uint8_t * response_buffer, uint16_t response_buffer_size){ 647 648 uint16_t attribute_type_len; 649 switch (request_len){ 650 case 7: 651 attribute_type_len = 2; 652 break; 653 case 21: 654 attribute_type_len = 16; 655 break; 656 default: 657 return setup_error_invalid_pdu(response_buffer, ATT_READ_BY_TYPE_REQUEST); 658 } 659 660 uint16_t start_handle = little_endian_read_16(request_buffer, 1); 661 uint16_t end_handle = little_endian_read_16(request_buffer, 3); 662 return handle_read_by_type_request2(att_connection, response_buffer, response_buffer_size, start_handle, end_handle, attribute_type_len, &request_buffer[5]); 663 } 664 665 // 666 // MARK: ATT_READ_BY_TYPE_REQUEST 667 // 668 static uint16_t handle_read_request2(att_connection_t * att_connection, uint8_t * response_buffer, uint16_t response_buffer_size, uint16_t handle){ 669 670 log_info("ATT_READ_REQUEST: handle %04x", handle); 671 uint8_t request_type = ATT_READ_REQUEST; 672 673 att_iterator_t it; 674 int ok = att_find_handle(&it, handle); 675 if (!ok){ 676 return setup_error_invalid_handle(response_buffer, request_type, handle); 677 } 678 679 // check if handle can be read 680 if ((it.flags & ATT_PROPERTY_READ) == 0) { 681 return setup_error_read_not_permitted(response_buffer, request_type, handle); 682 } 683 684 // check security requirements 685 uint8_t error_code = att_validate_security(att_connection, ATT_READ, &it); 686 if (error_code) { 687 return setup_error(response_buffer, request_type, handle, error_code); 688 } 689 690 att_update_value_len(&it, att_connection->con_handle); 691 692 #ifdef ENABLE_ATT_DELAYED_RESPONSE 693 if (it.value_len == ATT_READ_RESPONSE_PENDING) return ATT_READ_RESPONSE_PENDING; 694 #endif 695 696 // store 697 uint16_t offset = 1; 698 uint16_t bytes_copied = att_copy_value(&it, 0, response_buffer + offset, response_buffer_size - offset, att_connection->con_handle); 699 offset += bytes_copied; 700 701 response_buffer[0] = ATT_READ_RESPONSE; 702 return offset; 703 } 704 705 static uint16_t handle_read_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 706 uint8_t * response_buffer, uint16_t response_buffer_size){ 707 708 if (request_len != 3) return setup_error_invalid_pdu(response_buffer, ATT_READ_REQUEST); 709 710 uint16_t handle = little_endian_read_16(request_buffer, 1); 711 return handle_read_request2(att_connection, response_buffer, response_buffer_size, handle); 712 } 713 714 //s 715 // MARK: ATT_READ_BLOB_REQUEST 0x0c 716 // 717 static uint16_t handle_read_blob_request2(att_connection_t * att_connection, uint8_t * response_buffer, uint16_t response_buffer_size, uint16_t handle, uint16_t value_offset){ 718 log_info("ATT_READ_BLOB_REQUEST: handle %04x, offset %u", handle, value_offset); 719 uint8_t request_type = ATT_READ_BLOB_REQUEST; 720 721 att_iterator_t it; 722 int ok = att_find_handle(&it, handle); 723 if (!ok){ 724 return setup_error_invalid_handle(response_buffer, request_type, handle); 725 } 726 727 // check if handle can be read 728 if ((it.flags & ATT_PROPERTY_READ) == 0) { 729 return setup_error_read_not_permitted(response_buffer, request_type, handle); 730 } 731 732 // check security requirements 733 uint8_t error_code = att_validate_security(att_connection, ATT_READ, &it); 734 if (error_code) { 735 return setup_error(response_buffer, request_type, handle, error_code); 736 } 737 738 att_update_value_len(&it, att_connection->con_handle); 739 740 #ifdef ENABLE_ATT_DELAYED_RESPONSE 741 if (it.value_len == ATT_READ_RESPONSE_PENDING) return ATT_READ_RESPONSE_PENDING; 742 #endif 743 744 if (value_offset > it.value_len){ 745 return setup_error_invalid_offset(response_buffer, request_type, handle); 746 } 747 748 // store 749 uint16_t offset = 1; 750 uint16_t bytes_copied = att_copy_value(&it, value_offset, response_buffer + offset, response_buffer_size - offset, att_connection->con_handle); 751 offset += bytes_copied; 752 753 response_buffer[0] = ATT_READ_BLOB_RESPONSE; 754 return offset; 755 } 756 757 static uint16_t handle_read_blob_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 758 uint8_t * response_buffer, uint16_t response_buffer_size){ 759 760 if (request_len != 5) return setup_error_invalid_pdu(response_buffer, ATT_READ_BLOB_REQUEST); 761 762 uint16_t handle = little_endian_read_16(request_buffer, 1); 763 uint16_t value_offset = little_endian_read_16(request_buffer, 3); 764 return handle_read_blob_request2(att_connection, response_buffer, response_buffer_size, handle, value_offset); 765 } 766 767 // 768 // MARK: ATT_READ_MULTIPLE_REQUEST 0x0e 769 // 770 static uint16_t handle_read_multiple_request2(att_connection_t * att_connection, uint8_t * response_buffer, uint16_t response_buffer_size, uint16_t num_handles, uint8_t * handles){ 771 log_info("ATT_READ_MULTIPLE_REQUEST: num handles %u", num_handles); 772 uint8_t request_type = ATT_READ_MULTIPLE_REQUEST; 773 774 // TODO: figure out which error to respond with 775 // if (num_handles < 2){ 776 // return setup_error(response_buffer, ATT_READ_MULTIPLE_REQUEST, handle, ???); 777 // } 778 779 uint16_t offset = 1; 780 781 int i; 782 uint8_t error_code = 0; 783 uint16_t handle = 0; 784 785 #ifdef ENABLE_ATT_DELAYED_RESPONSE 786 bool read_request_pending = false; 787 #endif 788 789 for (i=0;i<num_handles;i++){ 790 handle = little_endian_read_16(handles, i << 1); 791 792 if (handle == 0){ 793 return setup_error_invalid_handle(response_buffer, request_type, handle); 794 } 795 796 att_iterator_t it; 797 798 int ok = att_find_handle(&it, handle); 799 if (!ok){ 800 return setup_error_invalid_handle(response_buffer, request_type, handle); 801 } 802 803 // check if handle can be read 804 if ((it.flags & ATT_PROPERTY_READ) == 0) { 805 error_code = ATT_ERROR_READ_NOT_PERMITTED; 806 break; 807 } 808 809 // check security requirements 810 error_code = att_validate_security(att_connection, ATT_READ, &it); 811 if (error_code) break; 812 813 att_update_value_len(&it, att_connection->con_handle); 814 815 #ifdef ENABLE_ATT_DELAYED_RESPONSE 816 if (it.value_len == ATT_READ_RESPONSE_PENDING) { 817 read_request_pending = true; 818 } 819 if (read_request_pending) continue; 820 #endif 821 822 // store 823 uint16_t bytes_copied = att_copy_value(&it, 0, response_buffer + offset, response_buffer_size - offset, att_connection->con_handle); 824 offset += bytes_copied; 825 } 826 827 if (error_code){ 828 return setup_error(response_buffer, request_type, handle, error_code); 829 } 830 831 response_buffer[0] = ATT_READ_MULTIPLE_RESPONSE; 832 return offset; 833 } 834 static uint16_t handle_read_multiple_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 835 uint8_t * response_buffer, uint16_t response_buffer_size){ 836 837 // 1 byte opcode + two or more attribute handles (2 bytes each) 838 if ( (request_len < 5) || ((request_len & 1) == 0) ) return setup_error_invalid_pdu(response_buffer, 839 ATT_READ_MULTIPLE_REQUEST); 840 841 int num_handles = (request_len - 1) >> 1; 842 return handle_read_multiple_request2(att_connection, response_buffer, response_buffer_size, num_handles, &request_buffer[1]); 843 } 844 845 // 846 // MARK: ATT_READ_BY_GROUP_TYPE_REQUEST 0x10 847 // 848 // Only handles GATT_PRIMARY_SERVICE_UUID and GATT_SECONDARY_SERVICE_UUID 849 // Core v4.0, vol 3, part g, 2.5.3 850 // "The «Primary Service» and «Secondary Service» grouping types may be used in the Read By Group Type Request. 851 // The «Characteristic» grouping type shall not be used in the ATT Read By Group Type Request." 852 // 853 // NOTE: doesn't handle DYNAMIC values 854 // 855 // NOTE: we don't check for security as PRIMARY and SECONDAY SERVICE definition shouldn't be protected 856 // Core 4.0, vol 3, part g, 8.1 857 // "The list of services and characteristics that a device supports is not considered private or 858 // confidential information, and therefore the Service and Characteristic Discovery procedures 859 // shall always be permitted. " 860 // 861 static uint16_t handle_read_by_group_type_request2(att_connection_t * att_connection, uint8_t * response_buffer, uint16_t response_buffer_size, 862 uint16_t start_handle, uint16_t end_handle, 863 uint16_t attribute_type_len, uint8_t * attribute_type){ 864 865 UNUSED(att_connection); 866 867 log_info("ATT_READ_BY_GROUP_TYPE_REQUEST: from %04X to %04X, buffer size %u, type: ", start_handle, end_handle, response_buffer_size); 868 log_info_hexdump(attribute_type, attribute_type_len); 869 uint8_t request_type = ATT_READ_BY_GROUP_TYPE_REQUEST; 870 871 if ((start_handle > end_handle) || (start_handle == 0)){ 872 return setup_error_invalid_handle(response_buffer, request_type, start_handle); 873 } 874 875 // assert UUID is primary or secondary service uuid 876 uint16_t uuid16 = uuid16_from_uuid(attribute_type_len, attribute_type); 877 if ((uuid16 != GATT_PRIMARY_SERVICE_UUID) && (uuid16 != GATT_SECONDARY_SERVICE_UUID)){ 878 return setup_error(response_buffer, request_type, start_handle, ATT_ERROR_UNSUPPORTED_GROUP_TYPE); 879 } 880 881 uint16_t offset = 1; 882 uint16_t pair_len = 0; 883 uint16_t in_group = 0; 884 uint16_t group_start_handle = 0; 885 uint8_t const * group_start_value = NULL; 886 uint16_t prev_handle = 0; 887 888 att_iterator_t it; 889 att_iterator_init(&it); 890 while (att_iterator_has_next(&it)){ 891 att_iterator_fetch_next(&it); 892 893 if (it.handle && (it.handle < start_handle)) continue; 894 if (it.handle > end_handle) break; // (1) 895 896 // log_info("Handle 0x%04x", it.handle); 897 898 // close current tag, if within a group and a new service definition starts or we reach end of att db 899 if (in_group && 900 ((it.handle == 0) || att_iterator_match_uuid16(&it, GATT_PRIMARY_SERVICE_UUID) || att_iterator_match_uuid16(&it, GATT_SECONDARY_SERVICE_UUID))){ 901 // log_info("End of group, handle 0x%04x, val_len: %u", prev_handle, pair_len - 4); 902 903 little_endian_store_16(response_buffer, offset, group_start_handle); 904 offset += 2; 905 little_endian_store_16(response_buffer, offset, prev_handle); 906 offset += 2; 907 (void)memcpy(response_buffer + offset, group_start_value, 908 pair_len - 4); 909 offset += pair_len - 4; 910 in_group = 0; 911 912 // check if space for another handle pair available 913 if ((offset + pair_len) > response_buffer_size){ 914 break; 915 } 916 } 917 918 // keep track of previous handle 919 prev_handle = it.handle; 920 921 // does current attribute match 922 // log_info("compare: %04x == %04x", *(uint16_t*) context->attribute_type, *(uint16_t*) uuid); 923 if (it.handle && att_iterator_match_uuid(&it, attribute_type, attribute_type_len)) { 924 925 // check if value has same len as last one 926 uint16_t this_pair_len = 4 + it.value_len; 927 if (offset > 1){ 928 if (this_pair_len != pair_len) { 929 break; 930 } 931 } 932 933 // log_info("Begin of group, handle 0x%04x", it.handle); 934 935 // first 936 if (offset == 1) { 937 pair_len = this_pair_len; 938 response_buffer[offset] = this_pair_len; 939 offset++; 940 } 941 942 group_start_handle = it.handle; 943 group_start_value = it.value; 944 in_group = 1; 945 } 946 } 947 948 if (offset == 1){ 949 return setup_error_atribute_not_found(response_buffer, request_type, start_handle); 950 } 951 952 response_buffer[0] = ATT_READ_BY_GROUP_TYPE_RESPONSE; 953 return offset; 954 } 955 static uint16_t handle_read_by_group_type_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 956 uint8_t * response_buffer, uint16_t response_buffer_size){ 957 uint16_t attribute_type_len; 958 switch (request_len){ 959 case 7: 960 attribute_type_len = 2; 961 break; 962 case 21: 963 attribute_type_len = 16; 964 break; 965 default: 966 return setup_error_invalid_pdu(response_buffer, ATT_READ_BY_GROUP_TYPE_REQUEST); 967 } 968 969 uint16_t start_handle = little_endian_read_16(request_buffer, 1); 970 uint16_t end_handle = little_endian_read_16(request_buffer, 3); 971 return handle_read_by_group_type_request2(att_connection, response_buffer, response_buffer_size, start_handle, end_handle, attribute_type_len, &request_buffer[5]); 972 } 973 974 // 975 // MARK: ATT_WRITE_REQUEST 0x12 976 static uint16_t handle_write_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 977 uint8_t * response_buffer, uint16_t response_buffer_size){ 978 979 if (request_len < 3) return setup_error_invalid_pdu(response_buffer, ATT_WRITE_REQUEST); 980 981 uint8_t request_type = ATT_WRITE_REQUEST; 982 983 uint16_t handle = little_endian_read_16(request_buffer, 1); 984 att_iterator_t it; 985 int ok = att_find_handle(&it, handle); 986 if (!ok) { 987 return setup_error_invalid_handle(response_buffer, request_type, handle); 988 } 989 if (att_write_callback == NULL) { 990 return setup_error_write_not_permitted(response_buffer, request_type, handle); 991 } 992 if ((it.flags & ATT_PROPERTY_WRITE) == 0) { 993 return setup_error_write_not_permitted(response_buffer, request_type, handle); 994 } 995 if ((it.flags & ATT_PROPERTY_DYNAMIC) == 0) { 996 return setup_error_write_not_permitted(response_buffer, request_type, handle); 997 } 998 // check security requirements 999 int error_code = att_validate_security(att_connection, ATT_WRITE, &it); 1000 if (error_code) { 1001 return setup_error(response_buffer, request_type, handle, error_code); 1002 } 1003 att_persistent_ccc_cache(&it); 1004 error_code = (*att_write_callback)(att_connection->con_handle, handle, ATT_TRANSACTION_MODE_NONE, 0, request_buffer + 3, request_len - 3); 1005 1006 #ifdef ENABLE_ATT_DELAYED_RESPONSE 1007 if (error_code == ATT_ERROR_WRITE_RESPONSE_PENDING) return ATT_INTERNAL_WRITE_RESPONSE_PENDING; 1008 #endif 1009 1010 if (error_code) { 1011 return setup_error(response_buffer, request_type, handle, error_code); 1012 } 1013 response_buffer[0] = ATT_WRITE_RESPONSE; 1014 return 1; 1015 } 1016 1017 // 1018 // MARK: ATT_PREPARE_WRITE_REQUEST 0x16 1019 static uint16_t handle_prepare_write_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 1020 uint8_t * response_buffer, uint16_t response_buffer_size){ 1021 1022 UNUSED(response_buffer_size); 1023 1024 uint8_t request_type = ATT_PREPARE_WRITE_REQUEST; 1025 1026 if (request_len < 5) return setup_error_invalid_pdu(response_buffer, request_type); 1027 1028 uint16_t handle = little_endian_read_16(request_buffer, 1); 1029 uint16_t offset = little_endian_read_16(request_buffer, 3); 1030 if (att_write_callback == NULL) { 1031 return setup_error_write_not_permitted(response_buffer, request_type, handle); 1032 } 1033 att_iterator_t it; 1034 if (att_find_handle(&it, handle) == 0) { 1035 return setup_error_invalid_handle(response_buffer, request_type, handle); 1036 } 1037 if ((it.flags & ATT_PROPERTY_WRITE) == 0) { 1038 return setup_error_write_not_permitted(response_buffer, request_type, handle); 1039 } 1040 if ((it.flags & ATT_PROPERTY_DYNAMIC) == 0) { 1041 return setup_error_write_not_permitted(response_buffer, request_type, handle); 1042 } 1043 // check security requirements 1044 int error_code = att_validate_security(att_connection, ATT_WRITE, &it); 1045 if (error_code) { 1046 return setup_error(response_buffer, request_type, handle, error_code); 1047 } 1048 1049 error_code = (*att_write_callback)(att_connection->con_handle, handle, ATT_TRANSACTION_MODE_ACTIVE, offset, request_buffer + 5, request_len - 5); 1050 switch (error_code){ 1051 case 0: 1052 break; 1053 case ATT_ERROR_INVALID_OFFSET: 1054 case ATT_ERROR_INVALID_ATTRIBUTE_VALUE_LENGTH: 1055 // postpone to execute write request 1056 att_prepare_write_update_errors(error_code, handle); 1057 break; 1058 #ifdef ENABLE_ATT_DELAYED_RESPONSE 1059 case ATT_ERROR_WRITE_RESPONSE_PENDING: 1060 return ATT_INTERNAL_WRITE_RESPONSE_PENDING; 1061 #endif 1062 default: 1063 return setup_error(response_buffer, request_type, handle, error_code); 1064 } 1065 1066 // response: echo request 1067 (void)memcpy(response_buffer, request_buffer, request_len); 1068 response_buffer[0] = ATT_PREPARE_WRITE_RESPONSE; 1069 return request_len; 1070 } 1071 1072 /* 1073 * @brief transcation queue of prepared writes, e.g., after disconnect 1074 */ 1075 void att_clear_transaction_queue(att_connection_t * att_connection){ 1076 (*att_write_callback)(att_connection->con_handle, 0, ATT_TRANSACTION_MODE_CANCEL, 0, NULL, 0); 1077 } 1078 1079 // MARK: ATT_EXECUTE_WRITE_REQUEST 0x18 1080 // NOTE: security has been verified by handle_prepare_write_request 1081 static uint16_t handle_execute_write_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 1082 uint8_t * response_buffer, uint16_t response_buffer_size){ 1083 1084 UNUSED(response_buffer_size); 1085 1086 uint8_t request_type = ATT_EXECUTE_WRITE_REQUEST; 1087 1088 if (request_len < 2) return setup_error_invalid_pdu(response_buffer, request_type); 1089 1090 if (att_write_callback == NULL) { 1091 return setup_error_write_not_permitted(response_buffer, request_type, 0); 1092 } 1093 1094 if (request_buffer[1]) { 1095 // validate queued write 1096 if (att_prepare_write_error_code == 0){ 1097 att_prepare_write_error_code = (*att_write_callback)(att_connection->con_handle, 0, ATT_TRANSACTION_MODE_VALIDATE, 0, NULL, 0); 1098 } 1099 #ifdef ENABLE_ATT_DELAYED_RESPONSE 1100 if (att_prepare_write_error_code == ATT_ERROR_WRITE_RESPONSE_PENDING) return ATT_INTERNAL_WRITE_RESPONSE_PENDING; 1101 #endif 1102 // deliver queued errors 1103 if (att_prepare_write_error_code){ 1104 att_clear_transaction_queue(att_connection); 1105 uint8_t error_code = att_prepare_write_error_code; 1106 uint16_t handle = att_prepare_write_error_handle; 1107 att_prepare_write_reset(); 1108 return setup_error(response_buffer, request_type, handle, error_code); 1109 } 1110 att_write_callback(att_connection->con_handle, 0, ATT_TRANSACTION_MODE_EXECUTE, 0, NULL, 0); 1111 } else { 1112 att_clear_transaction_queue(att_connection); 1113 } 1114 response_buffer[0] = ATT_EXECUTE_WRITE_RESPONSE; 1115 return 1; 1116 } 1117 1118 // MARK: ATT_WRITE_COMMAND 0x52 1119 // Core 4.0, vol 3, part F, 3.4.5.3 1120 // "No Error Response or Write Response shall be sent in response to this command" 1121 static void handle_write_command(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, uint16_t required_flags){ 1122 1123 if (request_len < 3) return; 1124 1125 uint16_t handle = little_endian_read_16(request_buffer, 1); 1126 if (att_write_callback == NULL) return; 1127 1128 att_iterator_t it; 1129 int ok = att_find_handle(&it, handle); 1130 if (!ok) return; 1131 if ((it.flags & ATT_PROPERTY_DYNAMIC) == 0) return; 1132 if ((it.flags & required_flags) == 0) return; 1133 if (att_validate_security(att_connection, ATT_WRITE, &it)) return; 1134 att_persistent_ccc_cache(&it); 1135 (*att_write_callback)(att_connection->con_handle, handle, ATT_TRANSACTION_MODE_NONE, 0, request_buffer + 3, request_len - 3); 1136 } 1137 1138 // MARK: helper for ATT_HANDLE_VALUE_NOTIFICATION and ATT_HANDLE_VALUE_INDICATION 1139 static uint16_t prepare_handle_value(att_connection_t * att_connection, 1140 uint16_t handle, 1141 const uint8_t *value, 1142 uint16_t value_len, 1143 uint8_t * response_buffer){ 1144 little_endian_store_16(response_buffer, 1, handle); 1145 if (value_len > (att_connection->mtu - 3)){ 1146 value_len = att_connection->mtu - 3; 1147 } 1148 (void)memcpy(&response_buffer[3], value, value_len); 1149 return value_len + 3; 1150 } 1151 1152 // MARK: ATT_HANDLE_VALUE_NOTIFICATION 0x1b 1153 uint16_t att_prepare_handle_value_notification(att_connection_t * att_connection, 1154 uint16_t handle, 1155 const uint8_t *value, 1156 uint16_t value_len, 1157 uint8_t * response_buffer){ 1158 1159 response_buffer[0] = ATT_HANDLE_VALUE_NOTIFICATION; 1160 return prepare_handle_value(att_connection, handle, value, value_len, response_buffer); 1161 } 1162 1163 // MARK: ATT_HANDLE_VALUE_INDICATION 0x1d 1164 uint16_t att_prepare_handle_value_indication(att_connection_t * att_connection, 1165 uint16_t handle, 1166 const uint8_t *value, 1167 uint16_t value_len, 1168 uint8_t * response_buffer){ 1169 1170 response_buffer[0] = ATT_HANDLE_VALUE_INDICATION; 1171 return prepare_handle_value(att_connection, handle, value, value_len, response_buffer); 1172 } 1173 1174 // MARK: Dispatcher 1175 uint16_t att_handle_request(att_connection_t * att_connection, 1176 uint8_t * request_buffer, 1177 uint16_t request_len, 1178 uint8_t * response_buffer){ 1179 uint16_t response_len = 0; 1180 uint16_t response_buffer_size = att_connection->mtu; 1181 1182 switch (request_buffer[0]){ 1183 case ATT_EXCHANGE_MTU_REQUEST: 1184 response_len = handle_exchange_mtu_request(att_connection, request_buffer, request_len, response_buffer); 1185 break; 1186 case ATT_FIND_INFORMATION_REQUEST: 1187 response_len = handle_find_information_request(att_connection, request_buffer, request_len,response_buffer, response_buffer_size); 1188 break; 1189 case ATT_FIND_BY_TYPE_VALUE_REQUEST: 1190 response_len = handle_find_by_type_value_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1191 break; 1192 case ATT_READ_BY_TYPE_REQUEST: 1193 response_len = handle_read_by_type_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1194 break; 1195 case ATT_READ_REQUEST: 1196 response_len = handle_read_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1197 break; 1198 case ATT_READ_BLOB_REQUEST: 1199 response_len = handle_read_blob_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1200 break; 1201 case ATT_READ_MULTIPLE_REQUEST: 1202 response_len = handle_read_multiple_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1203 break; 1204 case ATT_READ_BY_GROUP_TYPE_REQUEST: 1205 response_len = handle_read_by_group_type_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1206 break; 1207 case ATT_WRITE_REQUEST: 1208 response_len = handle_write_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1209 break; 1210 case ATT_PREPARE_WRITE_REQUEST: 1211 response_len = handle_prepare_write_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1212 break; 1213 case ATT_EXECUTE_WRITE_REQUEST: 1214 response_len = handle_execute_write_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1215 break; 1216 case ATT_WRITE_COMMAND: 1217 handle_write_command(att_connection, request_buffer, request_len, ATT_PROPERTY_WRITE_WITHOUT_RESPONSE); 1218 break; 1219 #ifdef ENABLE_LE_SIGNED_WRITE 1220 case ATT_SIGNED_WRITE_COMMAND: 1221 handle_write_command(att_connection, request_buffer, request_len, ATT_PROPERTY_AUTHENTICATED_SIGNED_WRITE); 1222 break; 1223 #endif 1224 default: 1225 log_info("Unhandled ATT Command: %02X, DATA: ", request_buffer[0]); 1226 log_info_hexdump(&request_buffer[9], request_len-9); 1227 break; 1228 } 1229 return response_len; 1230 } 1231 1232 // returns 1 if service found. only primary service. 1233 bool gatt_server_get_get_handle_range_for_service_with_uuid16(uint16_t uuid16, uint16_t * start_handle, uint16_t * end_handle){ 1234 uint16_t in_group = 0; 1235 uint16_t prev_handle = 0; 1236 1237 uint8_t attribute_value[2]; 1238 int attribute_len = sizeof(attribute_value); 1239 little_endian_store_16(attribute_value, 0, uuid16); 1240 1241 att_iterator_t it; 1242 att_iterator_init(&it); 1243 while (att_iterator_has_next(&it)){ 1244 att_iterator_fetch_next(&it); 1245 int new_service_started = att_iterator_match_uuid16(&it, GATT_PRIMARY_SERVICE_UUID) || att_iterator_match_uuid16(&it, GATT_SECONDARY_SERVICE_UUID); 1246 1247 // close current tag, if within a group and a new service definition starts or we reach end of att db 1248 if (in_group && 1249 ((it.handle == 0) || new_service_started)){ 1250 *end_handle = prev_handle; 1251 return true; 1252 } 1253 1254 // keep track of previous handle 1255 prev_handle = it.handle; 1256 1257 // check if found 1258 if (it.handle && new_service_started && (attribute_len == it.value_len) && (memcmp(attribute_value, it.value, it.value_len) == 0)){ 1259 *start_handle = it.handle; 1260 in_group = true; 1261 } 1262 } 1263 return false; 1264 } 1265 1266 // returns false if not found 1267 uint16_t gatt_server_get_value_handle_for_characteristic_with_uuid16(uint16_t start_handle, uint16_t end_handle, uint16_t uuid16){ 1268 att_iterator_t it; 1269 att_iterator_init(&it); 1270 while (att_iterator_has_next(&it)){ 1271 att_iterator_fetch_next(&it); 1272 if (it.handle && (it.handle < start_handle)) continue; 1273 if (it.handle > end_handle) break; // (1) 1274 if (it.handle == 0) break; 1275 if (att_iterator_match_uuid16(&it, uuid16)) return it.handle; 1276 } 1277 return 0; 1278 } 1279 1280 uint16_t gatt_server_get_descriptor_handle_for_characteristic_with_uuid16(uint16_t start_handle, uint16_t end_handle, uint16_t characteristic_uuid16, uint16_t descriptor_uuid16){ 1281 att_iterator_t it; 1282 att_iterator_init(&it); 1283 int characteristic_found = 0; 1284 while (att_iterator_has_next(&it)){ 1285 att_iterator_fetch_next(&it); 1286 if (it.handle && (it.handle < start_handle)) continue; 1287 if (it.handle > end_handle) break; // (1) 1288 if (it.handle == 0) break; 1289 if (att_iterator_match_uuid16(&it, characteristic_uuid16)){ 1290 characteristic_found = 1; 1291 continue; 1292 } 1293 if (att_iterator_match_uuid16(&it, GATT_PRIMARY_SERVICE_UUID) 1294 || att_iterator_match_uuid16(&it, GATT_SECONDARY_SERVICE_UUID) 1295 || att_iterator_match_uuid16(&it, GATT_CHARACTERISTICS_UUID)){ 1296 if (characteristic_found) break; 1297 continue; 1298 } 1299 if (characteristic_found && att_iterator_match_uuid16(&it, descriptor_uuid16)){ 1300 return it.handle; 1301 } 1302 } 1303 return 0; 1304 } 1305 1306 // returns 0 if not found 1307 uint16_t gatt_server_get_client_configuration_handle_for_characteristic_with_uuid16(uint16_t start_handle, uint16_t end_handle, uint16_t characteristic_uuid16){ 1308 return gatt_server_get_descriptor_handle_for_characteristic_with_uuid16(start_handle, end_handle, characteristic_uuid16, GATT_CLIENT_CHARACTERISTICS_CONFIGURATION); 1309 } 1310 // returns 0 if not found 1311 1312 uint16_t gatt_server_get_server_configuration_handle_for_characteristic_with_uuid16(uint16_t start_handle, uint16_t end_handle, uint16_t characteristic_uuid16){ 1313 return gatt_server_get_descriptor_handle_for_characteristic_with_uuid16(start_handle, end_handle, characteristic_uuid16, GATT_SERVER_CHARACTERISTICS_CONFIGURATION); 1314 } 1315 1316 // returns 1 if service found. only primary service. 1317 int gatt_server_get_get_handle_range_for_service_with_uuid128(const uint8_t * uuid128, uint16_t * start_handle, uint16_t * end_handle){ 1318 uint16_t in_group = 0; 1319 uint16_t prev_handle = 0; 1320 1321 uint8_t attribute_value[16]; 1322 int attribute_len = sizeof(attribute_value); 1323 reverse_128(uuid128, attribute_value); 1324 1325 att_iterator_t it; 1326 att_iterator_init(&it); 1327 while (att_iterator_has_next(&it)){ 1328 att_iterator_fetch_next(&it); 1329 int new_service_started = att_iterator_match_uuid16(&it, GATT_PRIMARY_SERVICE_UUID) || att_iterator_match_uuid16(&it, GATT_SECONDARY_SERVICE_UUID); 1330 1331 // close current tag, if within a group and a new service definition starts or we reach end of att db 1332 if (in_group && 1333 ((it.handle == 0) || new_service_started)){ 1334 *end_handle = prev_handle; 1335 return 1; 1336 } 1337 1338 // keep track of previous handle 1339 prev_handle = it.handle; 1340 1341 // check if found 1342 if (it.handle && new_service_started && (attribute_len == it.value_len) && (memcmp(attribute_value, it.value, it.value_len) == 0)){ 1343 *start_handle = it.handle; 1344 in_group = 1; 1345 } 1346 } 1347 return 0; 1348 } 1349 1350 // returns 0 if not found 1351 uint16_t gatt_server_get_value_handle_for_characteristic_with_uuid128(uint16_t start_handle, uint16_t end_handle, const uint8_t * uuid128){ 1352 uint8_t attribute_value[16]; 1353 reverse_128(uuid128, attribute_value); 1354 att_iterator_t it; 1355 att_iterator_init(&it); 1356 while (att_iterator_has_next(&it)){ 1357 att_iterator_fetch_next(&it); 1358 if (it.handle && (it.handle < start_handle)) continue; 1359 if (it.handle > end_handle) break; // (1) 1360 if (it.handle == 0) break; 1361 if (att_iterator_match_uuid(&it, attribute_value, 16)) return it.handle; 1362 } 1363 return 0; 1364 } 1365 1366 // returns 0 if not found 1367 uint16_t gatt_server_get_client_configuration_handle_for_characteristic_with_uuid128(uint16_t start_handle, uint16_t end_handle, const uint8_t * uuid128){ 1368 uint8_t attribute_value[16]; 1369 reverse_128(uuid128, attribute_value); 1370 att_iterator_t it; 1371 att_iterator_init(&it); 1372 int characteristic_found = 0; 1373 while (att_iterator_has_next(&it)){ 1374 att_iterator_fetch_next(&it); 1375 if (it.handle && (it.handle < start_handle)) continue; 1376 if (it.handle > end_handle) break; // (1) 1377 if (it.handle == 0) break; 1378 if (att_iterator_match_uuid(&it, attribute_value, 16)){ 1379 characteristic_found = 1; 1380 continue; 1381 } 1382 if (att_iterator_match_uuid16(&it, GATT_PRIMARY_SERVICE_UUID) 1383 || att_iterator_match_uuid16(&it, GATT_SECONDARY_SERVICE_UUID) 1384 || att_iterator_match_uuid16(&it, GATT_CHARACTERISTICS_UUID)){ 1385 if (characteristic_found) break; 1386 continue; 1387 } 1388 if (characteristic_found && att_iterator_match_uuid16(&it, GATT_CLIENT_CHARACTERISTICS_CONFIGURATION)){ 1389 return it.handle; 1390 } 1391 } 1392 return 0; 1393 } 1394 1395 1396 // 1-item cache to optimize query during write_callback 1397 static void att_persistent_ccc_cache(att_iterator_t * it){ 1398 att_persistent_ccc_handle = it->handle; 1399 if (it->flags & ATT_PROPERTY_UUID128){ 1400 att_persistent_ccc_uuid16 = 0; 1401 } else { 1402 att_persistent_ccc_uuid16 = little_endian_read_16(it->uuid, 0); 1403 } 1404 } 1405 1406 bool att_is_persistent_ccc(uint16_t handle){ 1407 if (handle != att_persistent_ccc_handle){ 1408 att_iterator_t it; 1409 int ok = att_find_handle(&it, handle); 1410 if (!ok) return false; 1411 att_persistent_ccc_cache(&it); 1412 } 1413 return att_persistent_ccc_uuid16 == GATT_CLIENT_CHARACTERISTICS_CONFIGURATION; 1414 } 1415 1416 // att_read_callback helpers 1417 uint16_t att_read_callback_handle_blob(const uint8_t * blob, uint16_t blob_size, uint16_t offset, uint8_t * buffer, uint16_t buffer_size){ 1418 if (buffer){ 1419 uint16_t bytes_to_copy = btstack_min(blob_size - offset, buffer_size); 1420 (void)memcpy(buffer, &blob[offset], bytes_to_copy); 1421 return bytes_to_copy; 1422 } else { 1423 return blob_size; 1424 } 1425 } 1426 1427 uint16_t att_read_callback_handle_little_endian_32(uint32_t value, uint16_t offset, uint8_t * buffer, uint16_t buffer_size){ 1428 uint8_t value_buffer[4]; 1429 little_endian_store_32(value_buffer, 0, value); 1430 return att_read_callback_handle_blob(value_buffer, sizeof(value_buffer), offset, buffer, buffer_size); 1431 } 1432 1433 uint16_t att_read_callback_handle_little_endian_16(uint16_t value, uint16_t offset, uint8_t * buffer, uint16_t buffer_size){ 1434 uint8_t value_buffer[2]; 1435 little_endian_store_16(value_buffer, 0, value); 1436 return att_read_callback_handle_blob(value_buffer, sizeof(value_buffer), offset, buffer, buffer_size); 1437 } 1438 1439 uint16_t att_read_callback_handle_byte(uint8_t value, uint16_t offset, uint8_t * buffer, uint16_t buffer_size){ 1440 uint8_t value_buffer[1]; 1441 value_buffer[0] = value; 1442 return att_read_callback_handle_blob(value_buffer, sizeof(value_buffer), offset, buffer, buffer_size); 1443 } 1444