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 41 #include <stdio.h> 42 #include <string.h> 43 44 #include "ble/att_db.h" 45 #include "ble/core.h" 46 #include "bluetooth.h" 47 #include "btstack_debug.h" 48 #include "btstack_util.h" 49 50 typedef enum { 51 ATT_READ, 52 ATT_WRITE, 53 } att_operation_t; 54 55 // Buetooth Base UUID 00000000-0000-1000-8000-00805F9B34FB in little endian 56 static const uint8_t bluetooth_base_uuid[] = { 0xfb, 0x34, 0x9b, 0x5f, 0x80, 0x00, 0x00, 0x80, 0x00, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 57 58 59 static int is_Bluetooth_Base_UUID(uint8_t const *uuid){ 60 if (memcmp(&uuid[0], &bluetooth_base_uuid[0], 12)) return 0; 61 if (memcmp(&uuid[14], &bluetooth_base_uuid[14], 2)) return 0; 62 return 1; 63 64 } 65 66 static uint16_t uuid16_from_uuid(uint16_t uuid_len, uint8_t * uuid){ 67 if (uuid_len == 2) return little_endian_read_16(uuid, 0); 68 if (!is_Bluetooth_Base_UUID(uuid)) return 0; 69 return little_endian_read_16(uuid, 12); 70 } 71 72 // ATT Database 73 74 // new java-style iterator 75 typedef struct att_iterator { 76 // private 77 uint8_t const * att_ptr; 78 // public 79 uint16_t size; 80 uint16_t flags; 81 uint16_t handle; 82 uint8_t const * uuid; 83 uint16_t value_len; 84 uint8_t const * value; 85 } att_iterator_t; 86 87 static void att_persistent_ccc_cache(att_iterator_t * it); 88 89 static uint8_t const * att_db = NULL; 90 static att_read_callback_t att_read_callback = NULL; 91 static att_write_callback_t att_write_callback = NULL; 92 static uint8_t att_prepare_write_error_code = 0; 93 static uint16_t att_prepare_write_error_handle = 0x0000; 94 95 // single cache for att_is_persistent_ccc - stores flags before write callback 96 static uint16_t att_persistent_ccc_handle; 97 static uint16_t att_persistent_ccc_uuid16; 98 99 static void att_iterator_init(att_iterator_t *it){ 100 it->att_ptr = att_db; 101 } 102 103 static int att_iterator_has_next(att_iterator_t *it){ 104 return it->att_ptr != NULL; 105 } 106 107 static void att_iterator_fetch_next(att_iterator_t *it){ 108 it->size = little_endian_read_16(it->att_ptr, 0); 109 if (it->size == 0){ 110 it->flags = 0; 111 it->handle = 0; 112 it->uuid = NULL; 113 it->value_len = 0; 114 it->value = NULL; 115 it->att_ptr = NULL; 116 return; 117 } 118 it->flags = little_endian_read_16(it->att_ptr, 2); 119 it->handle = little_endian_read_16(it->att_ptr, 4); 120 it->uuid = &it->att_ptr[6]; 121 // handle 128 bit UUIDs 122 if (it->flags & ATT_PROPERTY_UUID128){ 123 it->value_len = it->size - 22; 124 it->value = &it->att_ptr[22]; 125 } else { 126 it->value_len = it->size - 8; 127 it->value = &it->att_ptr[8]; 128 } 129 // advance AFTER setting values 130 it->att_ptr += it->size; 131 } 132 133 static int att_iterator_match_uuid16(att_iterator_t *it, uint16_t uuid){ 134 if (it->handle == 0) return 0; 135 if (it->flags & ATT_PROPERTY_UUID128){ 136 if (!is_Bluetooth_Base_UUID(it->uuid)) return 0; 137 return little_endian_read_16(it->uuid, 12) == uuid; 138 } 139 return little_endian_read_16(it->uuid, 0) == uuid; 140 } 141 142 static int att_iterator_match_uuid(att_iterator_t *it, uint8_t *uuid, uint16_t uuid_len){ 143 if (it->handle == 0) return 0; 144 // input: UUID16 145 if (uuid_len == 2) { 146 return att_iterator_match_uuid16(it, little_endian_read_16(uuid, 0)); 147 } 148 // input and db: UUID128 149 if (it->flags & ATT_PROPERTY_UUID128){ 150 return memcmp(it->uuid, uuid, 16) == 0; 151 } 152 // input: UUID128, db: UUID16 153 if (!is_Bluetooth_Base_UUID(uuid)) return 0; 154 return little_endian_read_16(uuid, 12) == little_endian_read_16(it->uuid, 0); 155 } 156 157 158 static int att_find_handle(att_iterator_t *it, uint16_t handle){ 159 if (handle == 0) return 0; 160 att_iterator_init(it); 161 while (att_iterator_has_next(it)){ 162 att_iterator_fetch_next(it); 163 if (it->handle != handle) continue; 164 return 1; 165 } 166 return 0; 167 } 168 169 // experimental client API 170 uint16_t att_uuid_for_handle(uint16_t attribute_handle){ 171 att_iterator_t it; 172 int ok = att_find_handle(&it, attribute_handle); 173 if (!ok) return 0; 174 if (it.flags & ATT_PROPERTY_UUID128) return 0; 175 return little_endian_read_16(it.uuid, 0); 176 } 177 // end of client API 178 179 static void att_update_value_len(att_iterator_t *it, hci_con_handle_t con_handle){ 180 if ((it->flags & ATT_PROPERTY_DYNAMIC) == 0) return; 181 it->value_len = (*att_read_callback)(con_handle, it->handle, 0, NULL, 0); 182 return; 183 } 184 185 // copy attribute value from offset into buffer with given size 186 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){ 187 188 // DYNAMIC 189 if (it->flags & ATT_PROPERTY_DYNAMIC){ 190 return (*att_read_callback)(con_handle, it->handle, offset, buffer, buffer_size); 191 } 192 193 // STATIC 194 uint16_t bytes_to_copy = it->value_len - offset; 195 if (bytes_to_copy > buffer_size){ 196 bytes_to_copy = buffer_size; 197 } 198 memcpy(buffer, it->value, bytes_to_copy); 199 return bytes_to_copy; 200 } 201 202 void att_set_db(uint8_t const * db){ 203 att_db = db; 204 } 205 206 void att_set_read_callback(att_read_callback_t callback){ 207 att_read_callback = callback; 208 } 209 210 void att_set_write_callback(att_write_callback_t callback){ 211 att_write_callback = callback; 212 } 213 214 void att_dump_attributes(void){ 215 att_iterator_t it; 216 att_iterator_init(&it); 217 uint8_t uuid128[16]; 218 while (att_iterator_has_next(&it)){ 219 att_iterator_fetch_next(&it); 220 if (it.handle == 0) { 221 log_info("Handle: END"); 222 return; 223 } 224 log_info("Handle: 0x%04x, flags: 0x%04x, uuid: ", it.handle, it.flags); 225 if (it.flags & ATT_PROPERTY_UUID128){ 226 reverse_128(it.uuid, uuid128); 227 log_info("%s", uuid128_to_str(uuid128)); 228 } else { 229 log_info("%04x", little_endian_read_16(it.uuid, 0)); 230 } 231 log_info(", value_len: %u, value: ", it.value_len); 232 log_info_hexdump(it.value, it.value_len); 233 } 234 } 235 236 static void att_prepare_write_reset(void){ 237 att_prepare_write_error_code = 0; 238 att_prepare_write_error_handle = 0x0000; 239 } 240 241 static void att_prepare_write_update_errors(uint8_t error_code, uint16_t handle){ 242 // first ATT_ERROR_INVALID_ATTRIBUTE_VALUE_LENGTH has highest priority 243 if (error_code == ATT_ERROR_INVALID_ATTRIBUTE_VALUE_LENGTH && error_code != att_prepare_write_error_code){ 244 att_prepare_write_error_code = error_code; 245 att_prepare_write_error_handle = handle; 246 return; 247 } 248 // first ATT_ERROR_INVALID_OFFSET is next 249 if (error_code == ATT_ERROR_INVALID_OFFSET && att_prepare_write_error_code == 0){ 250 att_prepare_write_error_code = error_code; 251 att_prepare_write_error_handle = handle; 252 return; 253 } 254 } 255 256 static uint16_t setup_error(uint8_t * response_buffer, uint16_t request, uint16_t handle, uint8_t error_code){ 257 response_buffer[0] = ATT_ERROR_RESPONSE; 258 response_buffer[1] = request; 259 little_endian_store_16(response_buffer, 2, handle); 260 response_buffer[4] = error_code; 261 return 5; 262 } 263 264 static inline uint16_t setup_error_read_not_permitted(uint8_t * response_buffer, uint16_t request, uint16_t start_handle){ 265 return setup_error(response_buffer, request, start_handle, ATT_ERROR_READ_NOT_PERMITTED); 266 } 267 268 static inline uint16_t setup_error_write_not_permitted(uint8_t * response_buffer, uint16_t request, uint16_t start_handle){ 269 return setup_error(response_buffer, request, start_handle, ATT_ERROR_WRITE_NOT_PERMITTED); 270 } 271 272 static inline uint16_t setup_error_atribute_not_found(uint8_t * response_buffer, uint16_t request, uint16_t start_handle){ 273 return setup_error(response_buffer, request, start_handle, ATT_ERROR_ATTRIBUTE_NOT_FOUND); 274 } 275 276 static inline uint16_t setup_error_invalid_handle(uint8_t * response_buffer, uint16_t request, uint16_t handle){ 277 return setup_error(response_buffer, request, handle, ATT_ERROR_INVALID_HANDLE); 278 } 279 280 static inline uint16_t setup_error_invalid_offset(uint8_t * response_buffer, uint16_t request, uint16_t handle){ 281 return setup_error(response_buffer, request, handle, ATT_ERROR_INVALID_OFFSET); 282 } 283 284 static uint8_t att_validate_security(att_connection_t * att_connection, att_operation_t operation, att_iterator_t * it){ 285 int required_security_level = 0; 286 switch (operation){ 287 case ATT_READ: 288 if (it->flags & ATT_PROPERTY_READ_PERMISSION_BIT_0) { 289 required_security_level |= 1; 290 } 291 if (it->flags & ATT_PROPERTY_READ_PERMISSION_BIT_1) { 292 required_security_level |= 2; 293 } 294 break; 295 case ATT_WRITE: 296 if (it->flags & ATT_PROPERTY_WRITE_PERMISSION_BIT_0) { 297 required_security_level |= 1; 298 } 299 if (it->flags & ATT_PROPERTY_WRITE_PERMISSION_BIT_1) { 300 required_security_level |= 2; 301 } 302 break; 303 } 304 305 int required_encryption_size = it->flags >> 12; 306 if (required_encryption_size) required_encryption_size++; // store -1 to fit into 4 bit 307 308 log_debug("att_validate_security. flags 0x%04x - req enc size %u, req security level %u, authorized %u, authenticated %u, encryption_key_size %u", 309 it->flags, required_encryption_size, required_security_level, att_connection->authorized, att_connection->authenticated, att_connection->encryption_key_size); 310 311 if ((required_security_level >= ATT_SECURITY_AUTHORIZED) && (att_connection->authorized == 0)) { 312 return ATT_ERROR_INSUFFICIENT_AUTHORIZATION; 313 } 314 if ((required_security_level >= ATT_SECURITY_AUTHENTICATED) && (att_connection->authenticated == 0)) { 315 return ATT_ERROR_INSUFFICIENT_AUTHENTICATION; 316 } 317 if (required_security_level >= ATT_SECURITY_ENCRYPTED) { 318 if ((required_encryption_size > 0) && (att_connection->encryption_key_size == 0)){ 319 return ATT_ERROR_INSUFFICIENT_ENCRYPTION; 320 } 321 if (required_encryption_size > att_connection->encryption_key_size){ 322 return ATT_ERROR_INSUFFICIENT_ENCRYPTION_KEY_SIZE; 323 } 324 } 325 return 0; 326 } 327 328 // 329 // MARK: ATT_EXCHANGE_MTU_REQUEST 330 // 331 static uint16_t handle_exchange_mtu_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 332 uint8_t * response_buffer){ 333 334 UNUSED(request_len); 335 336 uint16_t client_rx_mtu = little_endian_read_16(request_buffer, 1); 337 338 // find min(local max mtu, remote mtu) and use as mtu for this connection 339 if (client_rx_mtu < att_connection->max_mtu){ 340 att_connection->mtu = client_rx_mtu; 341 } else { 342 att_connection->mtu = att_connection->max_mtu; 343 } 344 345 response_buffer[0] = ATT_EXCHANGE_MTU_RESPONSE; 346 little_endian_store_16(response_buffer, 1, att_connection->mtu); 347 return 3; 348 } 349 350 351 // 352 // MARK: ATT_FIND_INFORMATION_REQUEST 353 // 354 // TODO: handle other types then GATT_PRIMARY_SERVICE_UUID and GATT_SECONDARY_SERVICE_UUID 355 // 356 static uint16_t handle_find_information_request2(att_connection_t * att_connection, uint8_t * response_buffer, uint16_t response_buffer_size, 357 uint16_t start_handle, uint16_t end_handle){ 358 359 UNUSED(att_connection); 360 361 log_info("ATT_FIND_INFORMATION_REQUEST: from %04X to %04X", start_handle, end_handle); 362 uint8_t request_type = ATT_FIND_INFORMATION_REQUEST; 363 364 if (start_handle > end_handle || start_handle == 0){ 365 return setup_error_invalid_handle(response_buffer, request_type, start_handle); 366 } 367 368 uint16_t offset = 1; 369 uint16_t uuid_len = 0; 370 371 att_iterator_t it; 372 att_iterator_init(&it); 373 while (att_iterator_has_next(&it)){ 374 att_iterator_fetch_next(&it); 375 if (!it.handle) break; 376 if (it.handle > end_handle) break; 377 if (it.handle < start_handle) continue; 378 379 // log_info("Handle 0x%04x", it.handle); 380 381 uint16_t this_uuid_len = (it.flags & ATT_PROPERTY_UUID128) ? 16 : 2; 382 383 // check if value has same len as last one if not first result 384 if (offset > 1){ 385 if (this_uuid_len != uuid_len) { 386 break; 387 } 388 } 389 390 // first 391 if (offset == 1) { 392 uuid_len = this_uuid_len; 393 // set format field 394 response_buffer[offset] = (it.flags & ATT_PROPERTY_UUID128) ? 0x02 : 0x01; 395 offset++; 396 } 397 398 // space? 399 if (offset + 2 + uuid_len > response_buffer_size) break; 400 401 // store 402 little_endian_store_16(response_buffer, offset, it.handle); 403 offset += 2; 404 405 memcpy(response_buffer + offset, it.uuid, uuid_len); 406 offset += uuid_len; 407 } 408 409 if (offset == 1){ 410 return setup_error_atribute_not_found(response_buffer, request_type, start_handle); 411 } 412 413 response_buffer[0] = ATT_FIND_INFORMATION_REPLY; 414 return offset; 415 } 416 417 static uint16_t handle_find_information_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 418 uint8_t * response_buffer, uint16_t response_buffer_size){ 419 UNUSED(request_len); 420 return handle_find_information_request2(att_connection, response_buffer, response_buffer_size, little_endian_read_16(request_buffer, 1), little_endian_read_16(request_buffer, 3)); 421 } 422 423 // 424 // MARK: ATT_FIND_BY_TYPE_VALUE 425 // 426 // "Only attributes with attribute handles between and including the Starting Handle parameter 427 // and the Ending Handle parameter that match the requested attri- bute type and the attribute 428 // value that have sufficient permissions to allow reading will be returned" -> (1) 429 // 430 // TODO: handle other types then GATT_PRIMARY_SERVICE_UUID and GATT_SECONDARY_SERVICE_UUID 431 // 432 // NOTE: doesn't handle DYNAMIC values 433 // NOTE: only supports 16 bit UUIDs 434 // 435 static uint16_t handle_find_by_type_value_request2(att_connection_t * att_connection, uint8_t * response_buffer, uint16_t response_buffer_size, 436 uint16_t start_handle, uint16_t end_handle, 437 uint16_t attribute_type, uint16_t attribute_len, uint8_t* attribute_value){ 438 439 UNUSED(att_connection); 440 441 log_info("ATT_FIND_BY_TYPE_VALUE_REQUEST: from %04X to %04X, type %04X, value: ", start_handle, end_handle, attribute_type); 442 log_info_hexdump(attribute_value, attribute_len); 443 uint8_t request_type = ATT_FIND_BY_TYPE_VALUE_REQUEST; 444 445 if (start_handle > end_handle || start_handle == 0){ 446 return setup_error_invalid_handle(response_buffer, request_type, start_handle); 447 } 448 449 uint16_t offset = 1; 450 uint16_t in_group = 0; 451 uint16_t prev_handle = 0; 452 453 att_iterator_t it; 454 att_iterator_init(&it); 455 while (att_iterator_has_next(&it)){ 456 att_iterator_fetch_next(&it); 457 458 if (it.handle && it.handle < start_handle) continue; 459 if (it.handle > end_handle) break; // (1) 460 461 // close current tag, if within a group and a new service definition starts or we reach end of att db 462 if (in_group && 463 (it.handle == 0 || att_iterator_match_uuid16(&it, GATT_PRIMARY_SERVICE_UUID) || att_iterator_match_uuid16(&it, GATT_SECONDARY_SERVICE_UUID))){ 464 465 log_info("End of group, handle 0x%04x", prev_handle); 466 little_endian_store_16(response_buffer, offset, prev_handle); 467 offset += 2; 468 in_group = 0; 469 470 // check if space for another handle pair available 471 if (offset + 4 > response_buffer_size){ 472 break; 473 } 474 } 475 476 // keep track of previous handle 477 prev_handle = it.handle; 478 479 // does current attribute match 480 if (it.handle && att_iterator_match_uuid16(&it, attribute_type) && attribute_len == it.value_len && memcmp(attribute_value, it.value, it.value_len) == 0){ 481 log_info("Begin of group, handle 0x%04x", it.handle); 482 little_endian_store_16(response_buffer, offset, it.handle); 483 offset += 2; 484 in_group = 1; 485 } 486 } 487 488 if (offset == 1){ 489 return setup_error_atribute_not_found(response_buffer, request_type, start_handle); 490 } 491 492 response_buffer[0] = ATT_FIND_BY_TYPE_VALUE_RESPONSE; 493 return offset; 494 } 495 496 static uint16_t handle_find_by_type_value_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 497 uint8_t * response_buffer, uint16_t response_buffer_size){ 498 int attribute_len = request_len - 7; 499 return handle_find_by_type_value_request2(att_connection, response_buffer, response_buffer_size, little_endian_read_16(request_buffer, 1), 500 little_endian_read_16(request_buffer, 3), little_endian_read_16(request_buffer, 5), attribute_len, &request_buffer[7]); 501 } 502 503 // 504 // MARK: ATT_READ_BY_TYPE_REQUEST 505 // 506 static uint16_t handle_read_by_type_request2(att_connection_t * att_connection, uint8_t * response_buffer, uint16_t response_buffer_size, 507 uint16_t start_handle, uint16_t end_handle, 508 uint16_t attribute_type_len, uint8_t * attribute_type){ 509 510 log_info("ATT_READ_BY_TYPE_REQUEST: from %04X to %04X, type: ", start_handle, end_handle); 511 log_info_hexdump(attribute_type, attribute_type_len); 512 uint8_t request_type = ATT_READ_BY_TYPE_REQUEST; 513 514 if (start_handle > end_handle || start_handle == 0){ 515 return setup_error_invalid_handle(response_buffer, request_type, start_handle); 516 } 517 518 uint16_t offset = 1; 519 uint16_t pair_len = 0; 520 521 att_iterator_t it; 522 att_iterator_init(&it); 523 uint8_t error_code = 0; 524 uint16_t first_matching_but_unreadable_handle = 0; 525 526 #ifdef ENABLE_ATT_DELAYED_READ_RESPONSE 527 int read_request_pending = 0; 528 #endif 529 530 while (att_iterator_has_next(&it)){ 531 att_iterator_fetch_next(&it); 532 533 if (!it.handle) break; 534 if (it.handle < start_handle) continue; 535 if (it.handle > end_handle) break; // (1) 536 537 // does current attribute match 538 if (!att_iterator_match_uuid(&it, attribute_type, attribute_type_len)) continue; 539 540 // skip handles that cannot be read but rembember that there has been at least one 541 if ((it.flags & ATT_PROPERTY_READ) == 0) { 542 if (first_matching_but_unreadable_handle == 0) { 543 first_matching_but_unreadable_handle = it.handle; 544 } 545 continue; 546 } 547 548 // check security requirements 549 if ((it.flags & ATT_DB_FLAGS_READ_WITHOUT_AUTHENTICATION) == 0){ 550 error_code = att_validate_security(att_connection, ATT_READ, &it); 551 if (error_code) break; 552 } 553 554 att_update_value_len(&it, att_connection->con_handle); 555 556 #ifdef ENABLE_ATT_DELAYED_READ_RESPONSE 557 if (it.value_len == ATT_READ_RESPONSE_PENDING){ 558 read_request_pending = 1; 559 } 560 if (read_request_pending) continue; 561 #endif 562 563 // check if value has same len as last one 564 uint16_t this_pair_len = 2 + it.value_len; 565 if (offset > 1){ 566 if (pair_len != this_pair_len) { 567 break; 568 } 569 } 570 571 // first 572 if (offset == 1) { 573 pair_len = this_pair_len; 574 response_buffer[offset] = pair_len; 575 offset++; 576 } 577 578 // space? 579 if (offset + pair_len > response_buffer_size) { 580 if (offset > 2) break; 581 it.value_len = response_buffer_size - 4; 582 response_buffer[1] = 2 + it.value_len; 583 } 584 585 // store 586 little_endian_store_16(response_buffer, offset, it.handle); 587 offset += 2; 588 uint16_t bytes_copied = att_copy_value(&it, 0, response_buffer + offset, it.value_len, att_connection->con_handle); 589 offset += bytes_copied; 590 } 591 592 #ifdef ENABLE_ATT_DELAYED_READ_RESPONSE 593 if (read_request_pending) return ATT_READ_RESPONSE_PENDING; 594 #endif 595 596 // at least one attribute could be read 597 if (offset > 1){ 598 response_buffer[0] = ATT_READ_BY_TYPE_RESPONSE; 599 return offset; 600 } 601 602 // first attribute had an error 603 if (error_code){ 604 return setup_error(response_buffer, request_type, start_handle, error_code); 605 } 606 607 // no other errors, but all found attributes had been non-readable 608 if (first_matching_but_unreadable_handle){ 609 return setup_error_read_not_permitted(response_buffer, request_type, first_matching_but_unreadable_handle); 610 } 611 612 // attribute not found 613 return setup_error_atribute_not_found(response_buffer, request_type, start_handle); 614 } 615 616 static uint16_t handle_read_by_type_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 617 uint8_t * response_buffer, uint16_t response_buffer_size){ 618 int attribute_type_len; 619 if (request_len <= 7){ 620 attribute_type_len = 2; 621 } else { 622 attribute_type_len = 16; 623 } 624 return handle_read_by_type_request2(att_connection, response_buffer, response_buffer_size, little_endian_read_16(request_buffer, 1), little_endian_read_16(request_buffer, 3), attribute_type_len, &request_buffer[5]); 625 } 626 627 // 628 // MARK: ATT_READ_BY_TYPE_REQUEST 629 // 630 static uint16_t handle_read_request2(att_connection_t * att_connection, uint8_t * response_buffer, uint16_t response_buffer_size, uint16_t handle){ 631 632 log_info("ATT_READ_REQUEST: handle %04x", handle); 633 uint8_t request_type = ATT_READ_REQUEST; 634 635 att_iterator_t it; 636 int ok = att_find_handle(&it, handle); 637 if (!ok){ 638 return setup_error_invalid_handle(response_buffer, request_type, handle); 639 } 640 641 // check if handle can be read 642 if ((it.flags & ATT_PROPERTY_READ) == 0) { 643 return setup_error_read_not_permitted(response_buffer, request_type, handle); 644 } 645 646 // check security requirements 647 if ((it.flags & ATT_DB_FLAGS_READ_WITHOUT_AUTHENTICATION) == 0){ 648 uint8_t error_code = att_validate_security(att_connection, ATT_READ, &it); 649 if (error_code) { 650 return setup_error(response_buffer, request_type, handle, error_code); 651 } 652 } 653 654 att_update_value_len(&it, att_connection->con_handle); 655 656 #ifdef ENABLE_ATT_DELAYED_READ_RESPONSE 657 if (it.value_len == ATT_READ_RESPONSE_PENDING) return ATT_READ_RESPONSE_PENDING; 658 #endif 659 660 uint16_t offset = 1; 661 // limit data 662 if (offset + it.value_len > response_buffer_size) { 663 it.value_len = response_buffer_size - 1; 664 } 665 666 // store 667 uint16_t bytes_copied = att_copy_value(&it, 0, response_buffer + offset, it.value_len, att_connection->con_handle); 668 offset += bytes_copied; 669 670 response_buffer[0] = ATT_READ_RESPONSE; 671 return offset; 672 } 673 674 static uint16_t handle_read_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 675 uint8_t * response_buffer, uint16_t response_buffer_size){ 676 UNUSED(request_len); 677 return handle_read_request2(att_connection, response_buffer, response_buffer_size, little_endian_read_16(request_buffer, 1)); 678 } 679 680 // 681 // MARK: ATT_READ_BLOB_REQUEST 0x0c 682 // 683 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){ 684 log_info("ATT_READ_BLOB_REQUEST: handle %04x, offset %u", handle, value_offset); 685 uint8_t request_type = ATT_READ_BLOB_REQUEST; 686 687 att_iterator_t it; 688 int ok = att_find_handle(&it, handle); 689 if (!ok){ 690 return setup_error_invalid_handle(response_buffer, request_type, handle); 691 } 692 693 // check if handle can be read 694 if ((it.flags & ATT_PROPERTY_READ) == 0) { 695 return setup_error_read_not_permitted(response_buffer, request_type, handle); 696 } 697 698 // check security requirements 699 if ((it.flags & ATT_DB_FLAGS_READ_WITHOUT_AUTHENTICATION) == 0){ 700 uint8_t error_code = att_validate_security(att_connection, ATT_READ, &it); 701 if (error_code) { 702 return setup_error(response_buffer, request_type, handle, error_code); 703 } 704 } 705 706 att_update_value_len(&it, att_connection->con_handle); 707 708 #ifdef ENABLE_ATT_DELAYED_READ_RESPONSE 709 if (it.value_len == ATT_READ_RESPONSE_PENDING) return ATT_READ_RESPONSE_PENDING; 710 #endif 711 712 if (value_offset > it.value_len){ 713 return setup_error_invalid_offset(response_buffer, request_type, handle); 714 } 715 716 // limit data 717 uint16_t offset = 1; 718 if (offset + it.value_len - value_offset > response_buffer_size) { 719 it.value_len = response_buffer_size - 1 + value_offset; 720 } 721 722 // store 723 uint16_t bytes_copied = att_copy_value(&it, value_offset, response_buffer + offset, it.value_len - value_offset, att_connection->con_handle); 724 offset += bytes_copied; 725 726 response_buffer[0] = ATT_READ_BLOB_RESPONSE; 727 return offset; 728 } 729 730 static uint16_t handle_read_blob_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 731 uint8_t * response_buffer, uint16_t response_buffer_size){ 732 UNUSED(request_len); 733 return handle_read_blob_request2(att_connection, response_buffer, response_buffer_size, little_endian_read_16(request_buffer, 1), little_endian_read_16(request_buffer, 3)); 734 } 735 736 // 737 // MARK: ATT_READ_MULTIPLE_REQUEST 0x0e 738 // 739 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){ 740 log_info("ATT_READ_MULTIPLE_REQUEST: num handles %u", num_handles); 741 uint8_t request_type = ATT_READ_MULTIPLE_REQUEST; 742 743 // TODO: figure out which error to respond with 744 // if (num_handles < 2){ 745 // return setup_error(response_buffer, ATT_READ_MULTIPLE_REQUEST, handle, ???); 746 // } 747 748 uint16_t offset = 1; 749 750 int i; 751 uint8_t error_code = 0; 752 uint16_t handle = 0; 753 754 #ifdef ENABLE_ATT_DELAYED_READ_RESPONSE 755 int read_request_pending = 0; 756 #endif 757 758 for (i=0;i<num_handles;i++){ 759 handle = little_endian_read_16(handles, i << 1); 760 761 if (handle == 0){ 762 return setup_error_invalid_handle(response_buffer, request_type, handle); 763 } 764 765 att_iterator_t it; 766 767 int ok = att_find_handle(&it, handle); 768 if (!ok){ 769 return setup_error_invalid_handle(response_buffer, request_type, handle); 770 } 771 772 // check if handle can be read 773 if ((it.flags & ATT_PROPERTY_READ) == 0) { 774 error_code = ATT_ERROR_READ_NOT_PERMITTED; 775 break; 776 } 777 778 // check security requirements 779 if ((it.flags & ATT_DB_FLAGS_READ_WITHOUT_AUTHENTICATION) == 0){ 780 error_code = att_validate_security(att_connection, ATT_READ, &it); 781 if (error_code) break; 782 } 783 att_update_value_len(&it, att_connection->con_handle); 784 785 #ifdef ENABLE_ATT_DELAYED_READ_RESPONSE 786 if (it.value_len == ATT_READ_RESPONSE_PENDING) { 787 read_request_pending = 1; 788 } 789 if (read_request_pending) continue; 790 #endif 791 792 // limit data 793 if (offset + it.value_len > response_buffer_size) { 794 it.value_len = response_buffer_size - 1; 795 } 796 797 // store 798 uint16_t bytes_copied = att_copy_value(&it, 0, response_buffer + offset, it.value_len, att_connection->con_handle); 799 offset += bytes_copied; 800 } 801 802 if (error_code){ 803 return setup_error(response_buffer, request_type, handle, error_code); 804 } 805 806 response_buffer[0] = ATT_READ_MULTIPLE_RESPONSE; 807 return offset; 808 } 809 static uint16_t handle_read_multiple_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 810 uint8_t * response_buffer, uint16_t response_buffer_size){ 811 int num_handles = (request_len - 1) >> 1; 812 return handle_read_multiple_request2(att_connection, response_buffer, response_buffer_size, num_handles, &request_buffer[1]); 813 } 814 815 // 816 // MARK: ATT_READ_BY_GROUP_TYPE_REQUEST 0x10 817 // 818 // Only handles GATT_PRIMARY_SERVICE_UUID and GATT_SECONDARY_SERVICE_UUID 819 // Core v4.0, vol 3, part g, 2.5.3 820 // "The «Primary Service» and «Secondary Service» grouping types may be used in the Read By Group Type Request. 821 // The «Characteristic» grouping type shall not be used in the ATT Read By Group Type Request." 822 // 823 // NOTE: doesn't handle DYNAMIC values 824 // 825 // NOTE: we don't check for security as PRIMARY and SECONDAY SERVICE definition shouldn't be protected 826 // Core 4.0, vol 3, part g, 8.1 827 // "The list of services and characteristics that a device supports is not considered private or 828 // confidential information, and therefore the Service and Characteristic Discovery procedures 829 // shall always be permitted. " 830 // 831 static uint16_t handle_read_by_group_type_request2(att_connection_t * att_connection, uint8_t * response_buffer, uint16_t response_buffer_size, 832 uint16_t start_handle, uint16_t end_handle, 833 uint16_t attribute_type_len, uint8_t * attribute_type){ 834 835 UNUSED(att_connection); 836 837 log_info("ATT_READ_BY_GROUP_TYPE_REQUEST: from %04X to %04X, buffer size %u, type: ", start_handle, end_handle, response_buffer_size); 838 log_info_hexdump(attribute_type, attribute_type_len); 839 uint8_t request_type = ATT_READ_BY_GROUP_TYPE_REQUEST; 840 841 if (start_handle > end_handle || start_handle == 0){ 842 return setup_error_invalid_handle(response_buffer, request_type, start_handle); 843 } 844 845 // assert UUID is primary or secondary service uuid 846 uint16_t uuid16 = uuid16_from_uuid(attribute_type_len, attribute_type); 847 if (uuid16 != GATT_PRIMARY_SERVICE_UUID && uuid16 != GATT_SECONDARY_SERVICE_UUID){ 848 return setup_error(response_buffer, request_type, start_handle, ATT_ERROR_UNSUPPORTED_GROUP_TYPE); 849 } 850 851 uint16_t offset = 1; 852 uint16_t pair_len = 0; 853 uint16_t in_group = 0; 854 uint16_t group_start_handle = 0; 855 uint8_t const * group_start_value = NULL; 856 uint16_t prev_handle = 0; 857 858 att_iterator_t it; 859 att_iterator_init(&it); 860 while (att_iterator_has_next(&it)){ 861 att_iterator_fetch_next(&it); 862 863 if (it.handle && it.handle < start_handle) continue; 864 if (it.handle > end_handle) break; // (1) 865 866 // log_info("Handle 0x%04x", it.handle); 867 868 // close current tag, if within a group and a new service definition starts or we reach end of att db 869 if (in_group && 870 (it.handle == 0 || att_iterator_match_uuid16(&it, GATT_PRIMARY_SERVICE_UUID) || att_iterator_match_uuid16(&it, GATT_SECONDARY_SERVICE_UUID))){ 871 // log_info("End of group, handle 0x%04x, val_len: %u", prev_handle, pair_len - 4); 872 873 little_endian_store_16(response_buffer, offset, group_start_handle); 874 offset += 2; 875 little_endian_store_16(response_buffer, offset, prev_handle); 876 offset += 2; 877 memcpy(response_buffer + offset, group_start_value, pair_len - 4); 878 offset += pair_len - 4; 879 in_group = 0; 880 881 // check if space for another handle pair available 882 if (offset + pair_len > response_buffer_size){ 883 break; 884 } 885 } 886 887 // keep track of previous handle 888 prev_handle = it.handle; 889 890 // does current attribute match 891 // log_info("compare: %04x == %04x", *(uint16_t*) context->attribute_type, *(uint16_t*) uuid); 892 if (it.handle && att_iterator_match_uuid(&it, attribute_type, attribute_type_len)) { 893 894 // check if value has same len as last one 895 uint16_t this_pair_len = 4 + it.value_len; 896 if (offset > 1){ 897 if (this_pair_len != pair_len) { 898 break; 899 } 900 } 901 902 // log_info("Begin of group, handle 0x%04x", it.handle); 903 904 // first 905 if (offset == 1) { 906 pair_len = this_pair_len; 907 response_buffer[offset] = this_pair_len; 908 offset++; 909 } 910 911 group_start_handle = it.handle; 912 group_start_value = it.value; 913 in_group = 1; 914 } 915 } 916 917 if (offset == 1){ 918 return setup_error_atribute_not_found(response_buffer, request_type, start_handle); 919 } 920 921 response_buffer[0] = ATT_READ_BY_GROUP_TYPE_RESPONSE; 922 return offset; 923 } 924 static uint16_t handle_read_by_group_type_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 925 uint8_t * response_buffer, uint16_t response_buffer_size){ 926 int attribute_type_len; 927 if (request_len <= 7){ 928 attribute_type_len = 2; 929 } else { 930 attribute_type_len = 16; 931 } 932 return handle_read_by_group_type_request2(att_connection, response_buffer, response_buffer_size, little_endian_read_16(request_buffer, 1), little_endian_read_16(request_buffer, 3), attribute_type_len, &request_buffer[5]); 933 } 934 935 // 936 // MARK: ATT_WRITE_REQUEST 0x12 937 static uint16_t handle_write_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 938 uint8_t * response_buffer, uint16_t response_buffer_size){ 939 940 UNUSED(response_buffer_size); 941 942 uint8_t request_type = ATT_WRITE_REQUEST; 943 944 uint16_t handle = little_endian_read_16(request_buffer, 1); 945 att_iterator_t it; 946 int ok = att_find_handle(&it, handle); 947 if (!ok) { 948 return setup_error_invalid_handle(response_buffer, request_type, handle); 949 } 950 if (!att_write_callback) { 951 return setup_error_write_not_permitted(response_buffer, request_type, handle); 952 } 953 if ((it.flags & ATT_PROPERTY_WRITE) == 0) { 954 return setup_error_write_not_permitted(response_buffer, request_type, handle); 955 } 956 if ((it.flags & ATT_PROPERTY_DYNAMIC) == 0) { 957 return setup_error_write_not_permitted(response_buffer, request_type, handle); 958 } 959 // check security requirements 960 uint8_t error_code = att_validate_security(att_connection, ATT_WRITE, &it); 961 if (error_code) { 962 return setup_error(response_buffer, request_type, handle, error_code); 963 } 964 att_persistent_ccc_cache(&it); 965 error_code = (*att_write_callback)(att_connection->con_handle, handle, ATT_TRANSACTION_MODE_NONE, 0, request_buffer + 3, request_len - 3); 966 if (error_code) { 967 return setup_error(response_buffer, request_type, handle, error_code); 968 } 969 response_buffer[0] = ATT_WRITE_RESPONSE; 970 return 1; 971 } 972 973 // 974 // MARK: ATT_PREPARE_WRITE_REQUEST 0x16 975 static uint16_t handle_prepare_write_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 976 uint8_t * response_buffer, uint16_t response_buffer_size){ 977 978 UNUSED(response_buffer_size); 979 980 uint8_t request_type = ATT_PREPARE_WRITE_REQUEST; 981 982 uint16_t handle = little_endian_read_16(request_buffer, 1); 983 uint16_t offset = little_endian_read_16(request_buffer, 3); 984 if (!att_write_callback) { 985 return setup_error_write_not_permitted(response_buffer, request_type, handle); 986 } 987 att_iterator_t it; 988 int ok = att_find_handle(&it, handle); 989 if (!ok) { 990 return setup_error_invalid_handle(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 uint8_t 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 1004 error_code = (*att_write_callback)(att_connection->con_handle, handle, ATT_TRANSACTION_MODE_ACTIVE, offset, request_buffer + 5, request_len - 5); 1005 switch (error_code){ 1006 case 0: 1007 break; 1008 case ATT_ERROR_INVALID_OFFSET: 1009 case ATT_ERROR_INVALID_ATTRIBUTE_VALUE_LENGTH: 1010 // postpone to execute write request 1011 att_prepare_write_update_errors(error_code, handle); 1012 break; 1013 default: 1014 return setup_error(response_buffer, request_type, handle, error_code); 1015 } 1016 1017 // response: echo request 1018 memcpy(response_buffer, request_buffer, request_len); 1019 response_buffer[0] = ATT_PREPARE_WRITE_RESPONSE; 1020 return request_len; 1021 } 1022 1023 /* 1024 * @brief transcation queue of prepared writes, e.g., after disconnect 1025 */ 1026 void att_clear_transaction_queue(att_connection_t * att_connection){ 1027 (*att_write_callback)(att_connection->con_handle, 0, ATT_TRANSACTION_MODE_CANCEL, 0, NULL, 0); 1028 } 1029 1030 // MARK: ATT_EXECUTE_WRITE_REQUEST 0x18 1031 // NOTE: security has been verified by handle_prepare_write_request 1032 static uint16_t handle_execute_write_request(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 1033 uint8_t * response_buffer, uint16_t response_buffer_size){ 1034 1035 UNUSED(request_len); 1036 UNUSED(response_buffer_size); 1037 1038 uint8_t request_type = ATT_EXECUTE_WRITE_REQUEST; 1039 if (request_buffer[1]) { 1040 // validate queued write 1041 if (att_prepare_write_error_code == 0){ 1042 att_prepare_write_error_code = (*att_write_callback)(att_connection->con_handle, 0, ATT_TRANSACTION_MODE_VALIDATE, 0, NULL, 0); 1043 } 1044 // deliver queued errors 1045 if (att_prepare_write_error_code){ 1046 att_clear_transaction_queue(att_connection); 1047 uint8_t error_code = att_prepare_write_error_code; 1048 uint16_t handle = att_prepare_write_error_handle; 1049 att_prepare_write_reset(); 1050 return setup_error(response_buffer, request_type, handle, error_code); 1051 } 1052 att_write_callback(att_connection->con_handle, 0, ATT_TRANSACTION_MODE_EXECUTE, 0, NULL, 0); 1053 } else { 1054 att_clear_transaction_queue(att_connection); 1055 } 1056 response_buffer[0] = ATT_EXECUTE_WRITE_RESPONSE; 1057 return 1; 1058 } 1059 1060 // MARK: ATT_WRITE_COMMAND 0x52 1061 // Core 4.0, vol 3, part F, 3.4.5.3 1062 // "No Error Response or Write Response shall be sent in response to this command" 1063 static void handle_write_command(att_connection_t * att_connection, uint8_t * request_buffer, uint16_t request_len, 1064 uint8_t * response_buffer, uint16_t response_buffer_size){ 1065 1066 UNUSED(response_buffer); 1067 UNUSED(response_buffer_size); 1068 1069 uint16_t handle = little_endian_read_16(request_buffer, 1); 1070 if (!att_write_callback) return; 1071 1072 att_iterator_t it; 1073 int ok = att_find_handle(&it, handle); 1074 if (!ok) return; 1075 if ((it.flags & ATT_PROPERTY_DYNAMIC) == 0) return; 1076 if ((it.flags & ATT_PROPERTY_WRITE_WITHOUT_RESPONSE) == 0) return; 1077 if (att_validate_security(att_connection, ATT_WRITE, &it)) return; 1078 att_persistent_ccc_cache(&it); 1079 (*att_write_callback)(att_connection->con_handle, handle, ATT_TRANSACTION_MODE_NONE, 0, request_buffer + 3, request_len - 3); 1080 } 1081 1082 // MARK: helper for ATT_HANDLE_VALUE_NOTIFICATION and ATT_HANDLE_VALUE_INDICATION 1083 static uint16_t prepare_handle_value(att_connection_t * att_connection, 1084 uint16_t handle, 1085 uint8_t *value, 1086 uint16_t value_len, 1087 uint8_t * response_buffer){ 1088 little_endian_store_16(response_buffer, 1, handle); 1089 if (value_len > att_connection->mtu - 3){ 1090 value_len = att_connection->mtu - 3; 1091 } 1092 memcpy(&response_buffer[3], value, value_len); 1093 return value_len + 3; 1094 } 1095 1096 // MARK: ATT_HANDLE_VALUE_NOTIFICATION 0x1b 1097 uint16_t att_prepare_handle_value_notification(att_connection_t * att_connection, 1098 uint16_t handle, 1099 uint8_t *value, 1100 uint16_t value_len, 1101 uint8_t * response_buffer){ 1102 1103 response_buffer[0] = ATT_HANDLE_VALUE_NOTIFICATION; 1104 return prepare_handle_value(att_connection, handle, value, value_len, response_buffer); 1105 } 1106 1107 // MARK: ATT_HANDLE_VALUE_INDICATION 0x1d 1108 uint16_t att_prepare_handle_value_indication(att_connection_t * att_connection, 1109 uint16_t handle, 1110 uint8_t *value, 1111 uint16_t value_len, 1112 uint8_t * response_buffer){ 1113 1114 response_buffer[0] = ATT_HANDLE_VALUE_INDICATION; 1115 return prepare_handle_value(att_connection, handle, value, value_len, response_buffer); 1116 } 1117 1118 // MARK: Dispatcher 1119 uint16_t att_handle_request(att_connection_t * att_connection, 1120 uint8_t * request_buffer, 1121 uint16_t request_len, 1122 uint8_t * response_buffer){ 1123 uint16_t response_len = 0; 1124 uint16_t response_buffer_size = att_connection->mtu; 1125 1126 switch (request_buffer[0]){ 1127 case ATT_EXCHANGE_MTU_REQUEST: 1128 response_len = handle_exchange_mtu_request(att_connection, request_buffer, request_len, response_buffer); 1129 break; 1130 case ATT_FIND_INFORMATION_REQUEST: 1131 response_len = handle_find_information_request(att_connection, request_buffer, request_len,response_buffer, response_buffer_size); 1132 break; 1133 case ATT_FIND_BY_TYPE_VALUE_REQUEST: 1134 response_len = handle_find_by_type_value_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1135 break; 1136 case ATT_READ_BY_TYPE_REQUEST: 1137 response_len = handle_read_by_type_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1138 break; 1139 case ATT_READ_REQUEST: 1140 response_len = handle_read_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1141 break; 1142 case ATT_READ_BLOB_REQUEST: 1143 response_len = handle_read_blob_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1144 break; 1145 case ATT_READ_MULTIPLE_REQUEST: 1146 response_len = handle_read_multiple_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1147 break; 1148 case ATT_READ_BY_GROUP_TYPE_REQUEST: 1149 response_len = handle_read_by_group_type_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1150 break; 1151 case ATT_WRITE_REQUEST: 1152 response_len = handle_write_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1153 break; 1154 case ATT_PREPARE_WRITE_REQUEST: 1155 response_len = handle_prepare_write_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1156 break; 1157 case ATT_EXECUTE_WRITE_REQUEST: 1158 response_len = handle_execute_write_request(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1159 break; 1160 case ATT_WRITE_COMMAND: 1161 handle_write_command(att_connection, request_buffer, request_len, response_buffer, response_buffer_size); 1162 break; 1163 #ifdef ENABLE_LE_SIGNED_WRITE 1164 case ATT_SIGNED_WRITE_COMMAND: 1165 log_info("handle_signed_write_command preprocessed by att_server.c"); 1166 break; 1167 #endif 1168 default: 1169 log_info("Unhandled ATT Command: %02X, DATA: ", request_buffer[0]); 1170 log_info_hexdump(&request_buffer[9], request_len-9); 1171 break; 1172 } 1173 return response_len; 1174 } 1175 1176 // returns 1 if service found. only primary service. 1177 int gatt_server_get_get_handle_range_for_service_with_uuid16(uint16_t uuid16, uint16_t * start_handle, uint16_t * end_handle){ 1178 uint16_t in_group = 0; 1179 uint16_t prev_handle = 0; 1180 1181 uint8_t attribute_value[2]; 1182 int attribute_len = sizeof(attribute_value); 1183 little_endian_store_16(attribute_value, 0, uuid16); 1184 1185 att_iterator_t it; 1186 att_iterator_init(&it); 1187 while (att_iterator_has_next(&it)){ 1188 att_iterator_fetch_next(&it); 1189 int new_service_started = att_iterator_match_uuid16(&it, GATT_PRIMARY_SERVICE_UUID) || att_iterator_match_uuid16(&it, GATT_SECONDARY_SERVICE_UUID); 1190 1191 // close current tag, if within a group and a new service definition starts or we reach end of att db 1192 if (in_group && 1193 (it.handle == 0 || new_service_started)){ 1194 *end_handle = prev_handle; 1195 return 1; 1196 } 1197 1198 // keep track of previous handle 1199 prev_handle = it.handle; 1200 1201 // check if found 1202 if (it.handle && new_service_started && attribute_len == it.value_len && memcmp(attribute_value, it.value, it.value_len) == 0){ 1203 *start_handle = it.handle; 1204 in_group = 1; 1205 } 1206 } 1207 return 0; 1208 } 1209 1210 // returns 0 if not found 1211 uint16_t gatt_server_get_value_handle_for_characteristic_with_uuid16(uint16_t start_handle, uint16_t end_handle, uint16_t uuid16){ 1212 att_iterator_t it; 1213 att_iterator_init(&it); 1214 while (att_iterator_has_next(&it)){ 1215 att_iterator_fetch_next(&it); 1216 if (it.handle && it.handle < start_handle) continue; 1217 if (it.handle > end_handle) break; // (1) 1218 if (it.handle == 0) break; 1219 if (att_iterator_match_uuid16(&it, uuid16)) return it.handle; 1220 } 1221 return 0; 1222 } 1223 1224 // returns 0 if not found 1225 uint16_t gatt_server_get_client_configuration_handle_for_characteristic_with_uuid16(uint16_t start_handle, uint16_t end_handle, uint16_t uuid16){ 1226 att_iterator_t it; 1227 att_iterator_init(&it); 1228 int characteristic_found = 0; 1229 while (att_iterator_has_next(&it)){ 1230 att_iterator_fetch_next(&it); 1231 if (it.handle && it.handle < start_handle) continue; 1232 if (it.handle > end_handle) break; // (1) 1233 if (it.handle == 0) break; 1234 if (att_iterator_match_uuid16(&it, uuid16)){ 1235 characteristic_found = 1; 1236 continue; 1237 } 1238 if (att_iterator_match_uuid16(&it, GATT_PRIMARY_SERVICE_UUID) 1239 || att_iterator_match_uuid16(&it, GATT_SECONDARY_SERVICE_UUID) 1240 || att_iterator_match_uuid16(&it, GATT_CHARACTERISTICS_UUID)){ 1241 if (characteristic_found) break; 1242 continue; 1243 } 1244 if (att_iterator_match_uuid16(&it, GATT_CLIENT_CHARACTERISTICS_CONFIGURATION)){ 1245 return it.handle; 1246 } 1247 } 1248 return 0; 1249 } 1250 1251 // 1-item cache to optimize query during write_callback 1252 static void att_persistent_ccc_cache(att_iterator_t * it){ 1253 att_persistent_ccc_handle = it->handle; 1254 if (it->flags & ATT_PROPERTY_UUID128){ 1255 att_persistent_ccc_uuid16 = 0; 1256 } else { 1257 att_persistent_ccc_uuid16 = little_endian_read_16(it->uuid, 0); 1258 } 1259 } 1260 1261 int att_is_persistent_ccc(uint16_t handle){ 1262 if (handle != att_persistent_ccc_handle){ 1263 att_iterator_t it; 1264 int ok = att_find_handle(&it, handle); 1265 if (!ok) return 0; 1266 att_persistent_ccc_cache(&it); 1267 } 1268 return att_persistent_ccc_uuid16 == GATT_CLIENT_CHARACTERISTICS_CONFIGURATION; 1269 } 1270 1271 // att_read_callback helpers 1272 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){ 1273 if (buffer){ 1274 uint16_t bytes_to_copy = btstack_min(blob_size - offset, buffer_size); 1275 memcpy(buffer, &blob[offset], bytes_to_copy); 1276 return bytes_to_copy; 1277 } else { 1278 return blob_size; 1279 } 1280 } 1281 1282 uint16_t att_read_callback_handle_little_endian_32(uint32_t value, uint16_t offset, uint8_t * buffer, uint16_t buffer_size){ 1283 uint8_t value_buffer[4]; 1284 little_endian_store_32(value_buffer, 0, value); 1285 return att_read_callback_handle_blob(value_buffer, sizeof(value_buffer), offset, buffer, buffer_size); 1286 } 1287 1288 uint16_t att_read_callback_handle_little_endian_16(uint16_t value, uint16_t offset, uint8_t * buffer, uint16_t buffer_size){ 1289 uint8_t value_buffer[2]; 1290 little_endian_store_16(value_buffer, 0, value); 1291 return att_read_callback_handle_blob(value_buffer, sizeof(value_buffer), offset, buffer, buffer_size); 1292 } 1293 1294 uint16_t att_read_callback_handle_byte(uint8_t value, uint16_t offset, uint8_t * buffer, uint16_t buffer_size){ 1295 uint8_t value_buffer[1]; 1296 value_buffer[0] = value; 1297 return att_read_callback_handle_blob(value_buffer, sizeof(value_buffer), offset, buffer, buffer_size); 1298 } 1299