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 == 2u) return little_endian_read_16(uuid, 0u); 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 == 0u){ 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) != 0u){ 126 it->value_len = it->size - 22u; 127 it->value = &it->att_ptr[22]; 128 } else { 129 it->value_len = it->size - 8u; 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 == 0u) return 0u; 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 == 0u) return 0u; 147 // input: UUID16 148 if (uuid_len == 2u) { 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) != 0u){ 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 == 0u) return 0u; 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) != 0u) return 0u; 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) == 0u) 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) != 0u){ 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 log_info("att_set_db %p", db); 213 att_db = db; 214 } 215 216 void att_set_read_callback(att_read_callback_t callback){ 217 att_read_callback = callback; 218 } 219 220 void att_set_write_callback(att_write_callback_t callback){ 221 att_write_callback = callback; 222 } 223 224 void att_dump_attributes(void){ 225 att_iterator_t it; 226 att_iterator_init(&it); 227 uint8_t uuid128[16]; 228 log_info("att_dump_attributes, table %p", att_db); 229 while (att_iterator_has_next(&it)){ 230 att_iterator_fetch_next(&it); 231 if (it.handle == 0u) { 232 log_info("Handle: END"); 233 return; 234 } 235 log_info("Handle: 0x%04x, flags: 0x%04x, uuid: ", it.handle, it.flags); 236 if ((it.flags & ATT_PROPERTY_UUID128) != 0u){ 237 reverse_128(it.uuid, uuid128); 238 log_info("%s", uuid128_to_str(uuid128)); 239 } else { 240 log_info("%04x", little_endian_read_16(it.uuid, 0)); 241 } 242 log_info(", value_len: %u, value: ", it.value_len); 243 log_info_hexdump(it.value, it.value_len); 244 } 245 } 246 247 static void att_prepare_write_reset(void){ 248 att_prepare_write_error_code = 0; 249 att_prepare_write_error_handle = 0x0000; 250 } 251 252 static void att_prepare_write_update_errors(uint8_t error_code, uint16_t handle){ 253 // first ATT_ERROR_INVALID_ATTRIBUTE_VALUE_LENGTH has highest priority 254 if ((error_code == ATT_ERROR_INVALID_ATTRIBUTE_VALUE_LENGTH) && (error_code != att_prepare_write_error_code)){ 255 att_prepare_write_error_code = error_code; 256 att_prepare_write_error_handle = handle; 257 return; 258 } 259 // first ATT_ERROR_INVALID_OFFSET is next 260 if ((error_code == ATT_ERROR_INVALID_OFFSET) && (att_prepare_write_error_code == 0)){ 261 att_prepare_write_error_code = error_code; 262 att_prepare_write_error_handle = handle; 263 return; 264 } 265 } 266 267 static uint16_t setup_error(uint8_t * response_buffer, uint16_t request, uint16_t handle, uint8_t error_code){ 268 response_buffer[0] = ATT_ERROR_RESPONSE; 269 response_buffer[1] = request; 270 little_endian_store_16(response_buffer, 2, handle); 271 response_buffer[4] = error_code; 272 return 5; 273 } 274 275 static inline uint16_t setup_error_read_not_permitted(uint8_t * response_buffer, uint16_t request, uint16_t start_handle){ 276 return setup_error(response_buffer, request, start_handle, ATT_ERROR_READ_NOT_PERMITTED); 277 } 278 279 static inline uint16_t setup_error_write_not_permitted(uint8_t * response_buffer, uint16_t request, uint16_t start_handle){ 280 return setup_error(response_buffer, request, start_handle, ATT_ERROR_WRITE_NOT_PERMITTED); 281 } 282 283 static inline uint16_t setup_error_atribute_not_found(uint8_t * response_buffer, uint16_t request, uint16_t start_handle){ 284 return setup_error(response_buffer, request, start_handle, ATT_ERROR_ATTRIBUTE_NOT_FOUND); 285 } 286 287 static inline uint16_t setup_error_invalid_handle(uint8_t * response_buffer, uint16_t request, uint16_t handle){ 288 return setup_error(response_buffer, request, handle, ATT_ERROR_INVALID_HANDLE); 289 } 290 291 static inline uint16_t setup_error_invalid_offset(uint8_t * response_buffer, uint16_t request, uint16_t handle){ 292 return setup_error(response_buffer, request, handle, ATT_ERROR_INVALID_OFFSET); 293 } 294 295 static inline uint16_t setup_error_invalid_pdu(uint8_t *response_buffer, uint16_t request) { 296 return setup_error(response_buffer, request, 0, ATT_ERROR_INVALID_PDU); 297 } 298 299 static uint8_t att_validate_security(att_connection_t * att_connection, att_operation_t operation, att_iterator_t * it){ 300 int required_security_level = 0; 301 bool requires_secure_connection = false; 302 switch (operation){ 303 case ATT_READ: 304 if ((it->flags & ATT_PROPERTY_READ_PERMISSION_BIT_0) != 0u){ 305 required_security_level |= 1; 306 } 307 if ((it->flags & ATT_PROPERTY_READ_PERMISSION_BIT_1) != 0u){ 308 required_security_level |= 2; 309 } 310 if ((it->flags & ATT_PROPERTY_READ_PERMISSION_SC) != 0u){ 311 requires_secure_connection = true; 312 } 313 break; 314 case ATT_WRITE: 315 if ((it->flags & ATT_PROPERTY_WRITE_PERMISSION_BIT_0) != 0u){ 316 required_security_level |= 1; 317 } 318 if ((it->flags & ATT_PROPERTY_WRITE_PERMISSION_BIT_1) != 0u){ 319 required_security_level |= 2; 320 } 321 if ((it->flags & ATT_PROPERTY_WRITE_PERMISSION_SC) != 0u){ 322 requires_secure_connection = true; 323 } 324 break; 325 } 326 327 uint8_t required_encryption_size = it->flags >> 12; 328 if (required_encryption_size != 0) required_encryption_size++; // store -1 to fit into 4 bit 329 330 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", 331 it->flags, required_security_level, required_encryption_size, att_connection->authorized, att_connection->authenticated, att_connection->encryption_key_size, att_connection->secure_connection); 332 333 bool sc_missing = requires_secure_connection && (att_connection->secure_connection == 0u); 334 switch (required_security_level){ 335 case ATT_SECURITY_AUTHORIZED: 336 if ((att_connection->authorized == 0u) || sc_missing){ 337 return ATT_ERROR_INSUFFICIENT_AUTHORIZATION; 338 } 339 /* fall through */ 340 case ATT_SECURITY_AUTHENTICATED: 341 if ((att_connection->authenticated == 0u) || sc_missing){ 342 return ATT_ERROR_INSUFFICIENT_AUTHENTICATION; 343 } 344 /* fall through */ 345 case ATT_SECURITY_ENCRYPTED: 346 if ((required_encryption_size > 0u) && ((att_connection->encryption_key_size == 0u) || sc_missing)){ 347 return ATT_ERROR_INSUFFICIENT_ENCRYPTION; 348 } 349 if (required_encryption_size > att_connection->encryption_key_size){ 350 return ATT_ERROR_INSUFFICIENT_ENCRYPTION_KEY_SIZE; 351 } 352 break; 353 default: 354 break; 355 } 356 return ATT_ERROR_SUCCESS; 357 } 358 359 // 360 // MARK: ATT_EXCHANGE_MTU_REQUEST 361 // 362 static uint16_t handle_exchange_mtu_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 363 uint8_t * response_buffer){ 364 365 if (request_len != 3u) return setup_error_invalid_pdu(response_buffer, ATT_EXCHANGE_MTU_REQUEST); 366 367 uint16_t client_rx_mtu = little_endian_read_16(request_buffer, 1); 368 369 // find min(local max mtu, remote mtu) >= ATT_DEFAULT_MTU and use as mtu for this connection 370 uint16_t min_mtu = btstack_min(client_rx_mtu, att_connection->max_mtu); 371 uint16_t new_mtu = btstack_max(ATT_DEFAULT_MTU, min_mtu); 372 att_connection->mtu = new_mtu; 373 374 response_buffer[0] = ATT_EXCHANGE_MTU_RESPONSE; 375 little_endian_store_16(response_buffer, 1, att_connection->mtu); 376 return 3; 377 } 378 379 380 // 381 // MARK: ATT_FIND_INFORMATION_REQUEST 382 // 383 // TODO: handle other types then GATT_PRIMARY_SERVICE_UUID and GATT_SECONDARY_SERVICE_UUID 384 // 385 static uint16_t handle_find_information_request2(att_connection_t * att_connection, uint8_t * response_buffer, uint16_t response_buffer_size, 386 uint16_t start_handle, uint16_t end_handle){ 387 388 UNUSED(att_connection); 389 390 log_info("ATT_FIND_INFORMATION_REQUEST: from %04X to %04X", start_handle, end_handle); 391 uint8_t request_type = ATT_FIND_INFORMATION_REQUEST; 392 393 if ((start_handle > end_handle) || (start_handle == 0u)){ 394 return setup_error_invalid_handle(response_buffer, request_type, start_handle); 395 } 396 397 uint16_t offset = 1; 398 uint16_t uuid_len = 0; 399 400 att_iterator_t it; 401 att_iterator_init(&it); 402 while (att_iterator_has_next(&it)){ 403 att_iterator_fetch_next(&it); 404 if (!it.handle) break; 405 if (it.handle > end_handle) break; 406 if (it.handle < start_handle) continue; 407 408 // log_info("Handle 0x%04x", it.handle); 409 410 uint16_t this_uuid_len = (it.flags & ATT_PROPERTY_UUID128) ? 16 : 2; 411 412 // check if value has same len as last one if not first result 413 if (offset > 1u){ 414 if (this_uuid_len != uuid_len) { 415 break; 416 } 417 } 418 419 // first 420 if (offset == 1u) { 421 uuid_len = this_uuid_len; 422 // set format field 423 response_buffer[offset] = (it.flags & ATT_PROPERTY_UUID128) ? 0x02 : 0x01; 424 offset++; 425 } 426 427 // space? 428 if ((offset + 2u + uuid_len) > response_buffer_size) break; 429 430 // store 431 little_endian_store_16(response_buffer, offset, it.handle); 432 offset += 2u; 433 434 (void)memcpy(response_buffer + offset, it.uuid, uuid_len); 435 offset += uuid_len; 436 } 437 438 if (offset == 1u){ 439 return setup_error_atribute_not_found(response_buffer, request_type, start_handle); 440 } 441 442 response_buffer[0] = ATT_FIND_INFORMATION_REPLY; 443 return offset; 444 } 445 446 static uint16_t handle_find_information_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 447 uint8_t * response_buffer, uint16_t response_buffer_size){ 448 449 if (request_len != 5u) return setup_error_invalid_pdu(response_buffer, ATT_FIND_INFORMATION_REQUEST); 450 451 uint16_t start_handle = little_endian_read_16(request_buffer, 1); 452 uint16_t end_handle = little_endian_read_16(request_buffer, 3); 453 return handle_find_information_request2(att_connection, response_buffer, response_buffer_size, start_handle, end_handle); 454 } 455 456 // 457 // MARK: ATT_FIND_BY_TYPE_VALUE 458 // 459 // "Only attributes with attribute handles between and including the Starting Handle parameter 460 // and the Ending Handle parameter that match the requested attri- bute type and the attribute 461 // value that have sufficient permissions to allow reading will be returned" -> (1) 462 // 463 // TODO: handle other types then GATT_PRIMARY_SERVICE_UUID and GATT_SECONDARY_SERVICE_UUID 464 // 465 // NOTE: doesn't handle DYNAMIC values 466 // NOTE: only supports 16 bit UUIDs 467 // 468 static uint16_t handle_find_by_type_value_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 469 uint8_t * response_buffer, uint16_t response_buffer_size){ 470 UNUSED(att_connection); 471 472 if (request_len < 7u) return setup_error_invalid_pdu(response_buffer, ATT_FIND_BY_TYPE_VALUE_REQUEST); 473 474 // parse request 475 uint16_t start_handle = little_endian_read_16(request_buffer, 1); 476 uint16_t end_handle = little_endian_read_16(request_buffer, 3); 477 uint16_t attribute_type = little_endian_read_16(request_buffer, 5); 478 const uint8_t *attribute_value = &request_buffer[7]; 479 uint16_t attribute_len = request_len - 7u; 480 481 log_info("ATT_FIND_BY_TYPE_VALUE_REQUEST: from %04X to %04X, type %04X, value: ", start_handle, end_handle, attribute_type); 482 log_info_hexdump(attribute_value, attribute_len); 483 uint8_t request_type = ATT_FIND_BY_TYPE_VALUE_REQUEST; 484 485 if ((start_handle > end_handle) || (start_handle == 0u)){ 486 return setup_error_invalid_handle(response_buffer, request_type, start_handle); 487 } 488 489 uint16_t offset = 1; 490 uint16_t in_group = 0; 491 uint16_t prev_handle = 0; 492 493 att_iterator_t it; 494 att_iterator_init(&it); 495 while (att_iterator_has_next(&it)){ 496 att_iterator_fetch_next(&it); 497 498 if (it.handle && (it.handle < start_handle)) continue; 499 if (it.handle > end_handle) break; // (1) 500 501 // close current tag, if within a group and a new service definition starts or we reach end of att db 502 if (in_group && 503 ((it.handle == 0u) || att_iterator_match_uuid16(&it, GATT_PRIMARY_SERVICE_UUID) || att_iterator_match_uuid16(&it, GATT_SECONDARY_SERVICE_UUID))){ 504 505 log_info("End of group, handle 0x%04x", prev_handle); 506 little_endian_store_16(response_buffer, offset, prev_handle); 507 offset += 2u; 508 in_group = 0; 509 510 // check if space for another handle pair available 511 if ((offset + 4u) > response_buffer_size){ 512 break; 513 } 514 } 515 516 // keep track of previous handle 517 prev_handle = it.handle; 518 519 // does current attribute match 520 if (it.handle && att_iterator_match_uuid16(&it, attribute_type) && (attribute_len == it.value_len) && (memcmp(attribute_value, it.value, it.value_len) == 0)){ 521 log_info("Begin of group, handle 0x%04x", it.handle); 522 little_endian_store_16(response_buffer, offset, it.handle); 523 offset += 2u; 524 in_group = 1; 525 } 526 } 527 528 if (offset == 1u){ 529 return setup_error_atribute_not_found(response_buffer, request_type, start_handle); 530 } 531 532 response_buffer[0] = ATT_FIND_BY_TYPE_VALUE_RESPONSE; 533 return offset; 534 } 535 536 // 537 // MARK: ATT_READ_BY_TYPE_REQUEST 538 // 539 static uint16_t handle_read_by_type_request2(att_connection_t * att_connection, uint8_t * response_buffer, uint16_t response_buffer_size, 540 uint16_t start_handle, uint16_t end_handle, 541 uint16_t attribute_type_len, uint8_t * attribute_type){ 542 543 log_info("ATT_READ_BY_TYPE_REQUEST: from %04X to %04X, type: ", start_handle, end_handle); 544 log_info_hexdump(attribute_type, attribute_type_len); 545 uint8_t request_type = ATT_READ_BY_TYPE_REQUEST; 546 547 if ((start_handle > end_handle) || (start_handle == 0u)){ 548 return setup_error_invalid_handle(response_buffer, request_type, start_handle); 549 } 550 551 uint16_t offset = 1; 552 uint16_t pair_len = 0; 553 554 att_iterator_t it; 555 att_iterator_init(&it); 556 uint8_t error_code = 0; 557 uint16_t first_matching_but_unreadable_handle = 0; 558 559 while (att_iterator_has_next(&it)){ 560 att_iterator_fetch_next(&it); 561 562 if ((it.handle == 0u ) || (it.handle > end_handle)) break; 563 564 if (it.handle < start_handle) continue; 565 566 // does current attribute match 567 if (!att_iterator_match_uuid(&it, attribute_type, attribute_type_len)) continue; 568 569 // skip handles that cannot be read but remember that there has been at least one 570 if ((it.flags & ATT_PROPERTY_READ) == 0u) { 571 if (first_matching_but_unreadable_handle == 0u) { 572 first_matching_but_unreadable_handle = it.handle; 573 } 574 continue; 575 } 576 577 // check security requirements 578 error_code = att_validate_security(att_connection, ATT_READ, &it); 579 if (error_code != 0u) break; 580 581 att_update_value_len(&it, att_connection->con_handle); 582 583 #ifdef ENABLE_ATT_DELAYED_RESPONSE 584 if (it.value_len == ATT_READ_RESPONSE_PENDING){ 585 return ATT_READ_RESPONSE_PENDING; 586 } 587 #endif 588 589 // check if value has same len as last one 590 uint16_t this_pair_len = 2u + it.value_len; 591 if ((offset > 1u) && (pair_len != this_pair_len)) { 592 break; 593 } 594 595 // first 596 if (offset == 1u) { 597 pair_len = this_pair_len; 598 response_buffer[offset] = pair_len; 599 offset++; 600 } 601 602 // space? 603 if ((offset + pair_len) > response_buffer_size) { 604 if (offset > 2u) break; 605 it.value_len = response_buffer_size - 4u; 606 response_buffer[1u] = 2u + it.value_len; 607 } 608 609 // store 610 little_endian_store_16(response_buffer, offset, it.handle); 611 offset += 2u; 612 uint16_t bytes_copied = att_copy_value(&it, 0, response_buffer + offset, it.value_len, att_connection->con_handle); 613 offset += bytes_copied; 614 } 615 616 // at least one attribute could be read 617 if (offset > 1u){ 618 response_buffer[0] = ATT_READ_BY_TYPE_RESPONSE; 619 return offset; 620 } 621 622 // first attribute had an error 623 if (error_code != 0u){ 624 return setup_error(response_buffer, request_type, start_handle, error_code); 625 } 626 627 // no other errors, but all found attributes had been non-readable 628 if (first_matching_but_unreadable_handle != 0u){ 629 return setup_error_read_not_permitted(response_buffer, request_type, first_matching_but_unreadable_handle); 630 } 631 632 // attribute not found 633 return setup_error_atribute_not_found(response_buffer, request_type, start_handle); 634 } 635 636 static uint16_t handle_read_by_type_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 637 uint8_t * response_buffer, uint16_t response_buffer_size){ 638 639 uint16_t attribute_type_len; 640 switch (request_len){ 641 case 7: 642 attribute_type_len = 2; 643 break; 644 case 21: 645 attribute_type_len = 16; 646 break; 647 default: 648 return setup_error_invalid_pdu(response_buffer, ATT_READ_BY_TYPE_REQUEST); 649 } 650 651 uint16_t start_handle = little_endian_read_16(request_buffer, 1); 652 uint16_t end_handle = little_endian_read_16(request_buffer, 3); 653 return handle_read_by_type_request2(att_connection, response_buffer, response_buffer_size, start_handle, end_handle, attribute_type_len, &request_buffer[5]); 654 } 655 656 // 657 // MARK: ATT_READ_BY_TYPE_REQUEST 658 // 659 static uint16_t handle_read_request2(att_connection_t * att_connection, uint8_t * response_buffer, uint16_t response_buffer_size, uint16_t handle){ 660 661 log_info("ATT_READ_REQUEST: handle %04x", handle); 662 uint8_t request_type = ATT_READ_REQUEST; 663 664 att_iterator_t it; 665 int ok = att_find_handle(&it, handle); 666 if (!ok){ 667 return setup_error_invalid_handle(response_buffer, request_type, handle); 668 } 669 670 // check if handle can be read 671 if ((it.flags & ATT_PROPERTY_READ) == 0u) { 672 return setup_error_read_not_permitted(response_buffer, request_type, handle); 673 } 674 675 // check security requirements 676 uint8_t error_code = att_validate_security(att_connection, ATT_READ, &it); 677 if (error_code) { 678 return setup_error(response_buffer, request_type, handle, error_code); 679 } 680 681 att_update_value_len(&it, att_connection->con_handle); 682 683 #ifdef ENABLE_ATT_DELAYED_RESPONSE 684 if (it.value_len == ATT_READ_RESPONSE_PENDING) return ATT_READ_RESPONSE_PENDING; 685 #endif 686 687 // store 688 uint16_t offset = 1; 689 uint16_t bytes_copied = att_copy_value(&it, 0, response_buffer + offset, response_buffer_size - offset, att_connection->con_handle); 690 offset += bytes_copied; 691 692 response_buffer[0] = ATT_READ_RESPONSE; 693 return offset; 694 } 695 696 static uint16_t handle_read_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 697 uint8_t * response_buffer, uint16_t response_buffer_size){ 698 699 if (request_len != 3u) return setup_error_invalid_pdu(response_buffer, ATT_READ_REQUEST); 700 701 uint16_t handle = little_endian_read_16(request_buffer, 1); 702 return handle_read_request2(att_connection, response_buffer, response_buffer_size, handle); 703 } 704 705 //s 706 // MARK: ATT_READ_BLOB_REQUEST 0x0c 707 // 708 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){ 709 log_info("ATT_READ_BLOB_REQUEST: handle %04x, offset %u", handle, value_offset); 710 uint8_t request_type = ATT_READ_BLOB_REQUEST; 711 712 att_iterator_t it; 713 int ok = att_find_handle(&it, handle); 714 if (!ok){ 715 return setup_error_invalid_handle(response_buffer, request_type, handle); 716 } 717 718 // check if handle can be read 719 if ((it.flags & ATT_PROPERTY_READ) == 0u) { 720 return setup_error_read_not_permitted(response_buffer, request_type, handle); 721 } 722 723 // check security requirements 724 uint8_t error_code = att_validate_security(att_connection, ATT_READ, &it); 725 if (error_code) { 726 return setup_error(response_buffer, request_type, handle, error_code); 727 } 728 729 att_update_value_len(&it, att_connection->con_handle); 730 731 #ifdef ENABLE_ATT_DELAYED_RESPONSE 732 if (it.value_len == ATT_READ_RESPONSE_PENDING) return ATT_READ_RESPONSE_PENDING; 733 #endif 734 735 if (value_offset > it.value_len){ 736 return setup_error_invalid_offset(response_buffer, request_type, handle); 737 } 738 739 // prepare response 740 response_buffer[0] = ATT_READ_BLOB_RESPONSE; 741 uint16_t offset = 1; 742 743 // fetch more data if available 744 if (value_offset < it.value_len){ 745 uint16_t bytes_copied = att_copy_value(&it, value_offset, &response_buffer[offset], response_buffer_size - offset, att_connection->con_handle); 746 offset += bytes_copied; 747 } 748 return offset; 749 } 750 751 static uint16_t handle_read_blob_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 752 uint8_t * response_buffer, uint16_t response_buffer_size){ 753 754 if (request_len != 5u) return setup_error_invalid_pdu(response_buffer, ATT_READ_BLOB_REQUEST); 755 756 uint16_t handle = little_endian_read_16(request_buffer, 1); 757 uint16_t value_offset = little_endian_read_16(request_buffer, 3); 758 return handle_read_blob_request2(att_connection, response_buffer, response_buffer_size, handle, value_offset); 759 } 760 761 // 762 // MARK: ATT_READ_MULTIPLE_REQUEST 0x0e 763 // 764 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){ 765 log_info("ATT_READ_MULTIPLE_REQUEST: num handles %u", num_handles); 766 uint8_t request_type = ATT_READ_MULTIPLE_REQUEST; 767 768 uint16_t offset = 1; 769 770 int i; 771 uint8_t error_code = 0; 772 uint16_t handle = 0; 773 774 #ifdef ENABLE_ATT_DELAYED_RESPONSE 775 bool read_request_pending = false; 776 #endif 777 778 for (i=0;i<num_handles;i++){ 779 handle = little_endian_read_16(handles, i << 1); 780 781 if (handle == 0u){ 782 return setup_error_invalid_handle(response_buffer, request_type, handle); 783 } 784 785 att_iterator_t it; 786 787 int ok = att_find_handle(&it, handle); 788 if (!ok){ 789 return setup_error_invalid_handle(response_buffer, request_type, handle); 790 } 791 792 // check if handle can be read 793 if ((it.flags & ATT_PROPERTY_READ) == 0u) { 794 error_code = ATT_ERROR_READ_NOT_PERMITTED; 795 break; 796 } 797 798 // check security requirements 799 error_code = att_validate_security(att_connection, ATT_READ, &it); 800 if (error_code) break; 801 802 att_update_value_len(&it, att_connection->con_handle); 803 804 #ifdef ENABLE_ATT_DELAYED_RESPONSE 805 if (it.value_len == ATT_READ_RESPONSE_PENDING) { 806 read_request_pending = true; 807 } 808 if (read_request_pending) continue; 809 #endif 810 811 // store 812 uint16_t bytes_copied = att_copy_value(&it, 0, response_buffer + offset, response_buffer_size - offset, att_connection->con_handle); 813 offset += bytes_copied; 814 } 815 816 if (error_code){ 817 return setup_error(response_buffer, request_type, handle, error_code); 818 } 819 820 response_buffer[0] = ATT_READ_MULTIPLE_RESPONSE; 821 return offset; 822 } 823 static uint16_t handle_read_multiple_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 824 uint8_t * response_buffer, uint16_t response_buffer_size){ 825 826 // 1 byte opcode + two or more attribute handles (2 bytes each) 827 if ( (request_len < 5u) || ((request_len & 1u) == 0u) ) return setup_error_invalid_pdu(response_buffer, 828 ATT_READ_MULTIPLE_REQUEST); 829 830 int num_handles = (request_len - 1u) >> 1u; 831 return handle_read_multiple_request2(att_connection, response_buffer, response_buffer_size, num_handles, &request_buffer[1]); 832 } 833 834 // 835 // MARK: ATT_READ_BY_GROUP_TYPE_REQUEST 0x10 836 // 837 // Only handles GATT_PRIMARY_SERVICE_UUID and GATT_SECONDARY_SERVICE_UUID 838 // Core v4.0, vol 3, part g, 2.5.3 839 // "The «Primary Service» and «Secondary Service» grouping types may be used in the Read By Group Type Request. 840 // The «Characteristic» grouping type shall not be used in the ATT Read By Group Type Request." 841 // 842 // NOTE: doesn't handle DYNAMIC values 843 // 844 // NOTE: we don't check for security as PRIMARY and SECONDAY SERVICE definition shouldn't be protected 845 // Core 4.0, vol 3, part g, 8.1 846 // "The list of services and characteristics that a device supports is not considered private or 847 // confidential information, and therefore the Service and Characteristic Discovery procedures 848 // shall always be permitted. " 849 // 850 static uint16_t handle_read_by_group_type_request2(att_connection_t * att_connection, uint8_t * response_buffer, uint16_t response_buffer_size, 851 uint16_t start_handle, uint16_t end_handle, 852 uint16_t attribute_type_len, uint8_t * attribute_type){ 853 854 UNUSED(att_connection); 855 856 log_info("ATT_READ_BY_GROUP_TYPE_REQUEST: from %04X to %04X, buffer size %u, type: ", start_handle, end_handle, response_buffer_size); 857 log_info_hexdump(attribute_type, attribute_type_len); 858 uint8_t request_type = ATT_READ_BY_GROUP_TYPE_REQUEST; 859 860 if ((start_handle > end_handle) || (start_handle == 0u)){ 861 return setup_error_invalid_handle(response_buffer, request_type, start_handle); 862 } 863 864 // assert UUID is primary or secondary service uuid 865 uint16_t uuid16 = uuid16_from_uuid(attribute_type_len, attribute_type); 866 if ((uuid16 != GATT_PRIMARY_SERVICE_UUID) && (uuid16 != GATT_SECONDARY_SERVICE_UUID)){ 867 return setup_error(response_buffer, request_type, start_handle, ATT_ERROR_UNSUPPORTED_GROUP_TYPE); 868 } 869 870 uint16_t offset = 1; 871 uint16_t pair_len = 0; 872 uint16_t in_group = 0; 873 uint16_t group_start_handle = 0; 874 uint8_t const * group_start_value = NULL; 875 uint16_t prev_handle = 0; 876 877 att_iterator_t it; 878 att_iterator_init(&it); 879 while (att_iterator_has_next(&it)){ 880 att_iterator_fetch_next(&it); 881 882 if (it.handle && (it.handle < start_handle)) continue; 883 if (it.handle > end_handle) break; // (1) 884 885 // log_info("Handle 0x%04x", it.handle); 886 887 // close current tag, if within a group and a new service definition starts or we reach end of att db 888 if (in_group && 889 ((it.handle == 0u) || att_iterator_match_uuid16(&it, GATT_PRIMARY_SERVICE_UUID) || att_iterator_match_uuid16(&it, GATT_SECONDARY_SERVICE_UUID))){ 890 // log_info("End of group, handle 0x%04x, val_len: %u", prev_handle, pair_len - 4); 891 892 little_endian_store_16(response_buffer, offset, group_start_handle); 893 offset += 2u; 894 little_endian_store_16(response_buffer, offset, prev_handle); 895 offset += 2u; 896 (void)memcpy(response_buffer + offset, group_start_value, 897 pair_len - 4u); 898 offset += pair_len - 4u; 899 in_group = 0; 900 901 // check if space for another handle pair available 902 if ((offset + pair_len) > response_buffer_size){ 903 break; 904 } 905 } 906 907 // keep track of previous handle 908 prev_handle = it.handle; 909 910 // does current attribute match 911 // log_info("compare: %04x == %04x", *(uint16_t*) context->attribute_type, *(uint16_t*) uuid); 912 if (it.handle && att_iterator_match_uuid(&it, attribute_type, attribute_type_len)) { 913 914 // check if value has same len as last one 915 uint16_t this_pair_len = 4u + it.value_len; 916 if (offset > 1u){ 917 if (this_pair_len != pair_len) { 918 break; 919 } 920 } 921 922 // log_info("Begin of group, handle 0x%04x", it.handle); 923 924 // first 925 if (offset == 1u) { 926 pair_len = this_pair_len; 927 response_buffer[offset] = this_pair_len; 928 offset++; 929 } 930 931 group_start_handle = it.handle; 932 group_start_value = it.value; 933 in_group = 1; 934 } 935 } 936 937 if (offset == 1u){ 938 return setup_error_atribute_not_found(response_buffer, request_type, start_handle); 939 } 940 941 response_buffer[0] = ATT_READ_BY_GROUP_TYPE_RESPONSE; 942 return offset; 943 } 944 static uint16_t handle_read_by_group_type_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 945 uint8_t * response_buffer, uint16_t response_buffer_size){ 946 uint16_t attribute_type_len; 947 switch (request_len){ 948 case 7: 949 attribute_type_len = 2; 950 break; 951 case 21: 952 attribute_type_len = 16; 953 break; 954 default: 955 return setup_error_invalid_pdu(response_buffer, ATT_READ_BY_GROUP_TYPE_REQUEST); 956 } 957 958 uint16_t start_handle = little_endian_read_16(request_buffer, 1); 959 uint16_t end_handle = little_endian_read_16(request_buffer, 3); 960 return handle_read_by_group_type_request2(att_connection, response_buffer, response_buffer_size, start_handle, end_handle, attribute_type_len, &request_buffer[5]); 961 } 962 963 // 964 // MARK: ATT_WRITE_REQUEST 0x12 965 static uint16_t handle_write_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 966 uint8_t * response_buffer, uint16_t response_buffer_size){ 967 968 UNUSED(response_buffer_size); 969 970 if (request_len < 3u) return setup_error_invalid_pdu(response_buffer, ATT_WRITE_REQUEST); 971 972 uint8_t request_type = ATT_WRITE_REQUEST; 973 974 uint16_t handle = little_endian_read_16(request_buffer, 1); 975 att_iterator_t it; 976 int ok = att_find_handle(&it, handle); 977 if (!ok) { 978 return setup_error_invalid_handle(response_buffer, request_type, handle); 979 } 980 if (att_write_callback == NULL) { 981 return setup_error_write_not_permitted(response_buffer, request_type, handle); 982 } 983 if ((it.flags & ATT_PROPERTY_WRITE) == 0u) { 984 return setup_error_write_not_permitted(response_buffer, request_type, handle); 985 } 986 if ((it.flags & ATT_PROPERTY_DYNAMIC) == 0u) { 987 return setup_error_write_not_permitted(response_buffer, request_type, handle); 988 } 989 // check security requirements 990 int error_code = att_validate_security(att_connection, ATT_WRITE, &it); 991 if (error_code) { 992 return setup_error(response_buffer, request_type, handle, error_code); 993 } 994 att_persistent_ccc_cache(&it); 995 error_code = (*att_write_callback)(att_connection->con_handle, handle, ATT_TRANSACTION_MODE_NONE, 0u, request_buffer + 3u, request_len - 3u); 996 997 #ifdef ENABLE_ATT_DELAYED_RESPONSE 998 if (error_code == ATT_ERROR_WRITE_RESPONSE_PENDING) return ATT_INTERNAL_WRITE_RESPONSE_PENDING; 999 #endif 1000 1001 if (error_code) { 1002 return setup_error(response_buffer, request_type, handle, error_code); 1003 } 1004 response_buffer[0] = ATT_WRITE_RESPONSE; 1005 return 1; 1006 } 1007 1008 // 1009 // MARK: ATT_PREPARE_WRITE_REQUEST 0x16 1010 static uint16_t handle_prepare_write_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 1011 uint8_t * response_buffer, uint16_t response_buffer_size){ 1012 1013 uint8_t request_type = ATT_PREPARE_WRITE_REQUEST; 1014 1015 if (request_len < 5u) return setup_error_invalid_pdu(response_buffer, request_type); 1016 1017 uint16_t handle = little_endian_read_16(request_buffer, 1); 1018 uint16_t offset = little_endian_read_16(request_buffer, 3); 1019 if (att_write_callback == NULL) { 1020 return setup_error_write_not_permitted(response_buffer, request_type, handle); 1021 } 1022 att_iterator_t it; 1023 if (att_find_handle(&it, handle) == 0) { 1024 return setup_error_invalid_handle(response_buffer, request_type, handle); 1025 } 1026 if ((it.flags & ATT_PROPERTY_WRITE) == 0u) { 1027 return setup_error_write_not_permitted(response_buffer, request_type, handle); 1028 } 1029 if ((it.flags & ATT_PROPERTY_DYNAMIC) == 0u) { 1030 return setup_error_write_not_permitted(response_buffer, request_type, handle); 1031 } 1032 // check security requirements 1033 int error_code = att_validate_security(att_connection, ATT_WRITE, &it); 1034 if (error_code) { 1035 return setup_error(response_buffer, request_type, handle, error_code); 1036 } 1037 1038 error_code = (*att_write_callback)(att_connection->con_handle, handle, ATT_TRANSACTION_MODE_ACTIVE, offset, request_buffer + 5u, request_len - 5u); 1039 switch (error_code){ 1040 case 0: 1041 break; 1042 case ATT_ERROR_INVALID_OFFSET: 1043 case ATT_ERROR_INVALID_ATTRIBUTE_VALUE_LENGTH: 1044 // postpone to execute write request 1045 att_prepare_write_update_errors(error_code, handle); 1046 break; 1047 #ifdef ENABLE_ATT_DELAYED_RESPONSE 1048 case ATT_ERROR_WRITE_RESPONSE_PENDING: 1049 return ATT_INTERNAL_WRITE_RESPONSE_PENDING; 1050 #endif 1051 default: 1052 return setup_error(response_buffer, request_type, handle, error_code); 1053 } 1054 1055 // response: echo request 1056 uint16_t bytes_to_echo = btstack_min(request_len, response_buffer_size); 1057 (void)memcpy(response_buffer, request_buffer, bytes_to_echo); 1058 response_buffer[0] = ATT_PREPARE_WRITE_RESPONSE; 1059 return request_len; 1060 } 1061 1062 /* 1063 * @brief transcation queue of prepared writes, e.g., after disconnect 1064 */ 1065 void att_clear_transaction_queue(att_connection_t * att_connection){ 1066 (*att_write_callback)(att_connection->con_handle, 0, ATT_TRANSACTION_MODE_CANCEL, 0, NULL, 0); 1067 } 1068 1069 // MARK: ATT_EXECUTE_WRITE_REQUEST 0x18 1070 // NOTE: security has been verified by handle_prepare_write_request 1071 static uint16_t handle_execute_write_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 1072 uint8_t * response_buffer, uint16_t response_buffer_size){ 1073 1074 UNUSED(response_buffer_size); 1075 1076 uint8_t request_type = ATT_EXECUTE_WRITE_REQUEST; 1077 1078 if (request_len < 2u) return setup_error_invalid_pdu(response_buffer, request_type); 1079 1080 if (att_write_callback == NULL) { 1081 return setup_error_write_not_permitted(response_buffer, request_type, 0); 1082 } 1083 1084 if (request_buffer[1]) { 1085 // validate queued write 1086 if (att_prepare_write_error_code == 0){ 1087 att_prepare_write_error_code = (*att_write_callback)(att_connection->con_handle, 0, ATT_TRANSACTION_MODE_VALIDATE, 0, NULL, 0); 1088 } 1089 #ifdef ENABLE_ATT_DELAYED_RESPONSE 1090 if (att_prepare_write_error_code == ATT_ERROR_WRITE_RESPONSE_PENDING) return ATT_INTERNAL_WRITE_RESPONSE_PENDING; 1091 #endif 1092 // deliver queued errors 1093 if (att_prepare_write_error_code){ 1094 att_clear_transaction_queue(att_connection); 1095 uint8_t error_code = att_prepare_write_error_code; 1096 uint16_t handle = att_prepare_write_error_handle; 1097 att_prepare_write_reset(); 1098 return setup_error(response_buffer, request_type, handle, error_code); 1099 } 1100 att_write_callback(att_connection->con_handle, 0, ATT_TRANSACTION_MODE_EXECUTE, 0, NULL, 0); 1101 } else { 1102 att_clear_transaction_queue(att_connection); 1103 } 1104 response_buffer[0] = ATT_EXECUTE_WRITE_RESPONSE; 1105 return 1; 1106 } 1107 1108 // MARK: ATT_WRITE_COMMAND 0x52 1109 // Core 4.0, vol 3, part F, 3.4.5.3 1110 // "No Error Response or Write Response shall be sent in response to this command" 1111 static void handle_write_command(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, uint16_t required_flags){ 1112 1113 if (request_len < 3u) return; 1114 1115 uint16_t handle = little_endian_read_16(request_buffer, 1); 1116 if (att_write_callback == NULL) return; 1117 1118 att_iterator_t it; 1119 int ok = att_find_handle(&it, handle); 1120 if (!ok) return; 1121 if ((it.flags & ATT_PROPERTY_DYNAMIC) == 0u) return; 1122 if ((it.flags & required_flags) == 0u) return; 1123 if (att_validate_security(att_connection, ATT_WRITE, &it)) return; 1124 att_persistent_ccc_cache(&it); 1125 (*att_write_callback)(att_connection->con_handle, handle, ATT_TRANSACTION_MODE_NONE, 0u, request_buffer + 3u, request_len - 3u); 1126 } 1127 1128 // MARK: helper for ATT_HANDLE_VALUE_NOTIFICATION and ATT_HANDLE_VALUE_INDICATION 1129 static uint16_t prepare_handle_value(att_connection_t * att_connection, 1130 uint16_t handle, 1131 const uint8_t *value, 1132 uint16_t value_len, 1133 uint8_t * response_buffer){ 1134 little_endian_store_16(response_buffer, 1, handle); 1135 if (value_len > (att_connection->mtu - 3u)){ 1136 value_len = att_connection->mtu - 3u; 1137 } 1138 (void)memcpy(&response_buffer[3], value, value_len); 1139 return value_len + 3u; 1140 } 1141 1142 // MARK: ATT_HANDLE_VALUE_NOTIFICATION 0x1b 1143 uint16_t att_prepare_handle_value_notification(att_connection_t * att_connection, 1144 uint16_t handle, 1145 const uint8_t *value, 1146 uint16_t value_len, 1147 uint8_t * response_buffer){ 1148 1149 response_buffer[0] = ATT_HANDLE_VALUE_NOTIFICATION; 1150 return prepare_handle_value(att_connection, handle, value, value_len, response_buffer); 1151 } 1152 1153 // MARK: ATT_HANDLE_VALUE_INDICATION 0x1d 1154 uint16_t att_prepare_handle_value_indication(att_connection_t * att_connection, 1155 uint16_t handle, 1156 const uint8_t *value, 1157 uint16_t value_len, 1158 uint8_t * response_buffer){ 1159 1160 response_buffer[0] = ATT_HANDLE_VALUE_INDICATION; 1161 return prepare_handle_value(att_connection, handle, value, value_len, response_buffer); 1162 } 1163 1164 // MARK: Dispatcher 1165 uint16_t att_handle_request(att_connection_t * att_connection, 1166 uint8_t * request_buffer, 1167 uint16_t request_len, 1168 uint8_t * response_buffer){ 1169 uint16_t response_len = 0; 1170 uint16_t response_buffer_size = att_connection->mtu; 1171 1172 switch (request_buffer[0]){ 1173 case ATT_EXCHANGE_MTU_REQUEST: 1174 response_len = handle_exchange_mtu_request(att_connection, request_buffer, request_len, response_buffer); 1175 break; 1176 case ATT_FIND_INFORMATION_REQUEST: 1177 response_len = handle_find_information_request(att_connection, request_buffer, request_len,response_buffer, response_buffer_size); 1178 break; 1179 case ATT_FIND_BY_TYPE_VALUE_REQUEST: 1180 response_len = handle_find_by_type_value_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1181 break; 1182 case ATT_READ_BY_TYPE_REQUEST: 1183 response_len = handle_read_by_type_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1184 break; 1185 case ATT_READ_REQUEST: 1186 response_len = handle_read_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1187 break; 1188 case ATT_READ_BLOB_REQUEST: 1189 response_len = handle_read_blob_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1190 break; 1191 case ATT_READ_MULTIPLE_REQUEST: 1192 response_len = handle_read_multiple_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1193 break; 1194 case ATT_READ_BY_GROUP_TYPE_REQUEST: 1195 response_len = handle_read_by_group_type_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1196 break; 1197 case ATT_WRITE_REQUEST: 1198 response_len = handle_write_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1199 break; 1200 case ATT_PREPARE_WRITE_REQUEST: 1201 response_len = handle_prepare_write_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1202 break; 1203 case ATT_EXECUTE_WRITE_REQUEST: 1204 response_len = handle_execute_write_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1205 break; 1206 case ATT_WRITE_COMMAND: 1207 handle_write_command(att_connection, request_buffer, request_len, ATT_PROPERTY_WRITE_WITHOUT_RESPONSE); 1208 break; 1209 #ifdef ENABLE_LE_SIGNED_WRITE 1210 case ATT_SIGNED_WRITE_COMMAND: 1211 handle_write_command(att_connection, request_buffer, request_len, ATT_PROPERTY_AUTHENTICATED_SIGNED_WRITE); 1212 break; 1213 #endif 1214 default: 1215 log_info("Unhandled ATT Command: %02X, DATA: ", request_buffer[0]); 1216 log_info_hexdump(&request_buffer[9u], request_len-9u); 1217 break; 1218 } 1219 return response_len; 1220 } 1221 1222 // returns 1 if service found. only primary service. 1223 bool gatt_server_get_get_handle_range_for_service_with_uuid16(uint16_t uuid16, uint16_t * start_handle, uint16_t * end_handle){ 1224 uint16_t in_group = 0; 1225 uint16_t prev_handle = 0; 1226 1227 uint8_t attribute_value[2]; 1228 int attribute_len = sizeof(attribute_value); 1229 little_endian_store_16(attribute_value, 0, uuid16); 1230 1231 att_iterator_t it; 1232 att_iterator_init(&it); 1233 while (att_iterator_has_next(&it)){ 1234 att_iterator_fetch_next(&it); 1235 int new_service_started = att_iterator_match_uuid16(&it, GATT_PRIMARY_SERVICE_UUID) || att_iterator_match_uuid16(&it, GATT_SECONDARY_SERVICE_UUID); 1236 1237 // close current tag, if within a group and a new service definition starts or we reach end of att db 1238 if (in_group && 1239 ((it.handle == 0u) || new_service_started)){ 1240 *end_handle = prev_handle; 1241 return true; 1242 } 1243 1244 // keep track of previous handle 1245 prev_handle = it.handle; 1246 1247 // check if found 1248 if (it.handle && new_service_started && (attribute_len == it.value_len) && (memcmp(attribute_value, it.value, it.value_len) == 0)){ 1249 *start_handle = it.handle; 1250 in_group = true; 1251 } 1252 } 1253 return false; 1254 } 1255 1256 // returns false if not found 1257 uint16_t gatt_server_get_value_handle_for_characteristic_with_uuid16(uint16_t start_handle, uint16_t end_handle, uint16_t uuid16){ 1258 att_iterator_t it; 1259 att_iterator_init(&it); 1260 while (att_iterator_has_next(&it)){ 1261 att_iterator_fetch_next(&it); 1262 if (it.handle && (it.handle < start_handle)) continue; 1263 if (it.handle > end_handle) break; // (1) 1264 if (it.handle == 0u) break; 1265 if (att_iterator_match_uuid16(&it, uuid16)) return it.handle; 1266 } 1267 return 0; 1268 } 1269 1270 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){ 1271 att_iterator_t it; 1272 att_iterator_init(&it); 1273 int characteristic_found = 0; 1274 while (att_iterator_has_next(&it)){ 1275 att_iterator_fetch_next(&it); 1276 if (it.handle && (it.handle < start_handle)) continue; 1277 if (it.handle > end_handle) break; // (1) 1278 if (it.handle == 0u) break; 1279 if (att_iterator_match_uuid16(&it, characteristic_uuid16)){ 1280 characteristic_found = 1; 1281 continue; 1282 } 1283 if (att_iterator_match_uuid16(&it, GATT_PRIMARY_SERVICE_UUID) 1284 || att_iterator_match_uuid16(&it, GATT_SECONDARY_SERVICE_UUID) 1285 || att_iterator_match_uuid16(&it, GATT_CHARACTERISTICS_UUID)){ 1286 if (characteristic_found) break; 1287 continue; 1288 } 1289 if (characteristic_found && att_iterator_match_uuid16(&it, descriptor_uuid16)){ 1290 return it.handle; 1291 } 1292 } 1293 return 0; 1294 } 1295 1296 // returns 0 if not found 1297 uint16_t gatt_server_get_client_configuration_handle_for_characteristic_with_uuid16(uint16_t start_handle, uint16_t end_handle, uint16_t characteristic_uuid16){ 1298 return gatt_server_get_descriptor_handle_for_characteristic_with_uuid16(start_handle, end_handle, characteristic_uuid16, GATT_CLIENT_CHARACTERISTICS_CONFIGURATION); 1299 } 1300 // returns 0 if not found 1301 1302 uint16_t gatt_server_get_server_configuration_handle_for_characteristic_with_uuid16(uint16_t start_handle, uint16_t end_handle, uint16_t characteristic_uuid16){ 1303 return gatt_server_get_descriptor_handle_for_characteristic_with_uuid16(start_handle, end_handle, characteristic_uuid16, GATT_SERVER_CHARACTERISTICS_CONFIGURATION); 1304 } 1305 1306 // returns 1 if service found. only primary service. 1307 int gatt_server_get_get_handle_range_for_service_with_uuid128(const uint8_t * uuid128, uint16_t * start_handle, uint16_t * end_handle){ 1308 uint16_t in_group = 0; 1309 uint16_t prev_handle = 0; 1310 1311 uint8_t attribute_value[16]; 1312 int attribute_len = sizeof(attribute_value); 1313 reverse_128(uuid128, attribute_value); 1314 1315 att_iterator_t it; 1316 att_iterator_init(&it); 1317 while (att_iterator_has_next(&it)){ 1318 att_iterator_fetch_next(&it); 1319 int new_service_started = att_iterator_match_uuid16(&it, GATT_PRIMARY_SERVICE_UUID) || att_iterator_match_uuid16(&it, GATT_SECONDARY_SERVICE_UUID); 1320 1321 // close current tag, if within a group and a new service definition starts or we reach end of att db 1322 if (in_group && 1323 ((it.handle == 0u) || new_service_started)){ 1324 *end_handle = prev_handle; 1325 return 1; 1326 } 1327 1328 // keep track of previous handle 1329 prev_handle = it.handle; 1330 1331 // check if found 1332 if (it.handle && new_service_started && (attribute_len == it.value_len) && (memcmp(attribute_value, it.value, it.value_len) == 0)){ 1333 *start_handle = it.handle; 1334 in_group = 1; 1335 } 1336 } 1337 return 0; 1338 } 1339 1340 // returns 0 if not found 1341 uint16_t gatt_server_get_value_handle_for_characteristic_with_uuid128(uint16_t start_handle, uint16_t end_handle, const uint8_t * uuid128){ 1342 uint8_t attribute_value[16]; 1343 reverse_128(uuid128, attribute_value); 1344 att_iterator_t it; 1345 att_iterator_init(&it); 1346 while (att_iterator_has_next(&it)){ 1347 att_iterator_fetch_next(&it); 1348 if (it.handle && (it.handle < start_handle)) continue; 1349 if (it.handle > end_handle) break; // (1) 1350 if (it.handle == 0u) break; 1351 if (att_iterator_match_uuid(&it, attribute_value, 16)) return it.handle; 1352 } 1353 return 0; 1354 } 1355 1356 // returns 0 if not found 1357 uint16_t gatt_server_get_client_configuration_handle_for_characteristic_with_uuid128(uint16_t start_handle, uint16_t end_handle, const uint8_t * uuid128){ 1358 uint8_t attribute_value[16]; 1359 reverse_128(uuid128, attribute_value); 1360 att_iterator_t it; 1361 att_iterator_init(&it); 1362 int characteristic_found = 0; 1363 while (att_iterator_has_next(&it)){ 1364 att_iterator_fetch_next(&it); 1365 if (it.handle && (it.handle < start_handle)) continue; 1366 if (it.handle > end_handle) break; // (1) 1367 if (it.handle == 0u) break; 1368 if (att_iterator_match_uuid(&it, attribute_value, 16)){ 1369 characteristic_found = 1; 1370 continue; 1371 } 1372 if (att_iterator_match_uuid16(&it, GATT_PRIMARY_SERVICE_UUID) 1373 || att_iterator_match_uuid16(&it, GATT_SECONDARY_SERVICE_UUID) 1374 || att_iterator_match_uuid16(&it, GATT_CHARACTERISTICS_UUID)){ 1375 if (characteristic_found) break; 1376 continue; 1377 } 1378 if (characteristic_found && att_iterator_match_uuid16(&it, GATT_CLIENT_CHARACTERISTICS_CONFIGURATION)){ 1379 return it.handle; 1380 } 1381 } 1382 return 0; 1383 } 1384 1385 1386 // 1-item cache to optimize query during write_callback 1387 static void att_persistent_ccc_cache(att_iterator_t * it){ 1388 att_persistent_ccc_handle = it->handle; 1389 if (it->flags & ATT_PROPERTY_UUID128){ 1390 att_persistent_ccc_uuid16 = 0; 1391 } else { 1392 att_persistent_ccc_uuid16 = little_endian_read_16(it->uuid, 0); 1393 } 1394 } 1395 1396 bool att_is_persistent_ccc(uint16_t handle){ 1397 if (handle != att_persistent_ccc_handle){ 1398 att_iterator_t it; 1399 int ok = att_find_handle(&it, handle); 1400 if (!ok) return false; 1401 att_persistent_ccc_cache(&it); 1402 } 1403 return att_persistent_ccc_uuid16 == GATT_CLIENT_CHARACTERISTICS_CONFIGURATION; 1404 } 1405 1406 // att_read_callback helpers 1407 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){ 1408 if (buffer){ 1409 uint16_t bytes_to_copy = btstack_min(blob_size - offset, buffer_size); 1410 (void)memcpy(buffer, &blob[offset], bytes_to_copy); 1411 return bytes_to_copy; 1412 } else { 1413 return blob_size; 1414 } 1415 } 1416 1417 uint16_t att_read_callback_handle_little_endian_32(uint32_t value, uint16_t offset, uint8_t * buffer, uint16_t buffer_size){ 1418 uint8_t value_buffer[4]; 1419 little_endian_store_32(value_buffer, 0, value); 1420 return att_read_callback_handle_blob(value_buffer, sizeof(value_buffer), offset, buffer, buffer_size); 1421 } 1422 1423 uint16_t att_read_callback_handle_little_endian_16(uint16_t value, uint16_t offset, uint8_t * buffer, uint16_t buffer_size){ 1424 uint8_t value_buffer[2]; 1425 little_endian_store_16(value_buffer, 0, value); 1426 return att_read_callback_handle_blob(value_buffer, sizeof(value_buffer), offset, buffer, buffer_size); 1427 } 1428 1429 uint16_t att_read_callback_handle_byte(uint8_t value, uint16_t offset, uint8_t * buffer, uint16_t buffer_size){ 1430 uint8_t value_buffer[1]; 1431 value_buffer[0] = value; 1432 return att_read_callback_handle_blob(value_buffer, sizeof(value_buffer), offset, buffer, buffer_size); 1433 } 1434 1435 #ifdef ENABLE_BTP 1436 1437 #include "btp.h" 1438 1439 static uint8_t btp_permissions_for_flags(uint16_t flags){ 1440 1441 // see BT_GATT_PERM_* 1442 // https://docs.zephyrproject.org/latest/reference/bluetooth/gatt.html 1443 // set bit indicates requirement, e.g. BTP_GATT_PERM_READ_AUTHN requires authenticated connection 1444 1445 uint8_t permissions = 0; 1446 1447 uint8_t read_security_level = 0; 1448 uint8_t write_security_level = 0; 1449 if (flags & ATT_PROPERTY_READ){ 1450 if (flags & ATT_PROPERTY_READ_PERMISSION_BIT_0) { 1451 read_security_level |= 1; 1452 } 1453 if (flags & ATT_PROPERTY_READ_PERMISSION_BIT_1) { 1454 read_security_level |= 2; 1455 } 1456 if (read_security_level == ATT_SECURITY_AUTHORIZED) { 1457 permissions |= BTP_GATT_PERM_READ_AUTHZ; 1458 } 1459 if (read_security_level == ATT_SECURITY_AUTHENTICATED) { 1460 permissions |= BTP_GATT_PERM_READ_AUTHN; 1461 } 1462 if (read_security_level == ATT_SECURITY_ENCRYPTED) { 1463 permissions |= BTP_GATT_PERM_READ_ENC; 1464 } 1465 if (read_security_level == ATT_SECURITY_NONE) { 1466 permissions |= BTP_GATT_PERM_READ; 1467 } 1468 } 1469 if (flags & (ATT_PROPERTY_WRITE | ATT_PROPERTY_WRITE_WITHOUT_RESPONSE)){ 1470 if (flags & ATT_PROPERTY_WRITE_PERMISSION_BIT_0) { 1471 write_security_level |= 1; 1472 } 1473 if (flags & ATT_PROPERTY_WRITE_PERMISSION_BIT_1) { 1474 write_security_level |= 2; 1475 } 1476 if (write_security_level == ATT_SECURITY_AUTHORIZED) { 1477 permissions |= BTP_GATT_PERM_WRITE_AUTHZ; 1478 } 1479 if (write_security_level == ATT_SECURITY_AUTHENTICATED) { 1480 permissions |= BTP_GATT_PERM_WRITE_AUTHN; 1481 } 1482 if (write_security_level == ATT_SECURITY_ENCRYPTED) { 1483 permissions |= BTP_GATT_PERM_WRITE_ENC; 1484 } 1485 if (write_security_level == ATT_SECURITY_NONE) { 1486 permissions |= BTP_GATT_PERM_WRITE; 1487 } 1488 } 1489 return permissions; 1490 } 1491 1492 uint16_t btp_att_get_attributes_by_uuid16(uint16_t start_handle, uint16_t end_handle, uint16_t uuid16, uint8_t * response_buffer, uint16_t response_buffer_size){ 1493 log_info("btp_att_get_attributes_by_uuid16 %04x from 0x%04x to 0x%04x, db %p", uuid16, start_handle, end_handle, att_db); 1494 att_dump_attributes(); 1495 1496 uint8_t num_attributes = 0; 1497 uint16_t pos = 1; 1498 1499 att_iterator_t it; 1500 att_iterator_init(&it); 1501 while (att_iterator_has_next(&it) && ((pos + 6) < response_buffer_size)){ 1502 att_iterator_fetch_next(&it); 1503 log_info("handle %04x", it.handle); 1504 if (it.handle == 0) break; 1505 if (it.handle < start_handle) continue; 1506 if (it.handle > end_handle) break; 1507 if ((uuid16 == 0) || att_iterator_match_uuid16(&it, uuid16)){ 1508 little_endian_store_16(response_buffer, pos, it.handle); 1509 pos += 2; 1510 response_buffer[pos++] = btp_permissions_for_flags(it.flags); 1511 response_buffer[pos++] = 2; 1512 little_endian_store_16(response_buffer, pos, uuid16); 1513 pos += 2; 1514 num_attributes++; 1515 } 1516 } 1517 response_buffer[0] = num_attributes; 1518 return pos; 1519 } 1520 1521 uint16_t btp_att_get_attributes_by_uuid128(uint16_t start_handle, uint16_t end_handle, const uint8_t * uuid128, uint8_t * response_buffer, uint16_t response_buffer_size){ 1522 uint8_t num_attributes = 0; 1523 uint16_t pos = 1; 1524 att_iterator_t it; 1525 att_iterator_init(&it); 1526 while (att_iterator_has_next(&it) && ((pos + 20) < response_buffer_size)){ 1527 att_iterator_fetch_next(&it); 1528 if (it.handle == 0) break; 1529 if (it.handle < start_handle) continue; 1530 if (it.handle > end_handle) break; 1531 if (att_iterator_match_uuid(&it, (uint8_t*) uuid128, 16)){ 1532 little_endian_store_16(response_buffer, pos, it.handle); 1533 pos += 2; 1534 response_buffer[pos++] = btp_permissions_for_flags(it.flags); 1535 response_buffer[pos++] = 16; 1536 reverse_128(uuid128, &response_buffer[pos]); 1537 pos += 16; 1538 num_attributes++; 1539 } 1540 } 1541 response_buffer[0] = num_attributes; 1542 return pos; 1543 } 1544 1545 uint16_t btp_att_get_attribute_value(att_connection_t * att_connection, uint16_t attribute_handle, uint8_t * response_buffer, uint16_t response_buffer_size){ 1546 att_iterator_t it; 1547 int ok = att_find_handle(&it, attribute_handle); 1548 if (!ok) return 0; 1549 1550 uint16_t pos = 0; 1551 // field: ATT_Response - simulate READ operation on given connection 1552 response_buffer[pos++] = att_validate_security(att_connection, ATT_READ, &it); 1553 // fetch len 1554 // assume: con handle not relevant here, else, it needs to get passed in 1555 // att_update_value_len(&it, HCI_CON_HANDLE_INVALID); 1556 uint16_t bytes_to_copy = btstack_min( response_buffer_size - 3, it.value_len); 1557 little_endian_store_16(response_buffer, pos, bytes_to_copy); 1558 pos += 2; 1559 // get value - only works for non-dynamic data 1560 if (it.value){ 1561 memcpy(&response_buffer[pos], it.value, bytes_to_copy); 1562 pos += bytes_to_copy; 1563 } 1564 return pos; 1565 } 1566 #endif 1567