1 /* 2 * Copyright (C) 2017 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__ "beacon.c" 39 40 #include "mesh/beacon.h" 41 42 #include <string.h> 43 44 #include "ble/core.h" 45 #include "bluetooth.h" 46 #include "bluetooth_data_types.h" 47 #include "btstack_debug.h" 48 #include "btstack_event.h" 49 #include "btstack_run_loop.h" 50 #include "btstack_util.h" 51 #include "gap.h" 52 53 #include "mesh/adv_bearer.h" 54 #include "mesh/gatt_bearer.h" 55 #include "mesh/mesh_foundation.h" 56 #include "mesh/mesh_iv_index_seq_number.h" 57 #include "mesh/mesh_keys.h" 58 59 #define BEACON_TYPE_UNPROVISIONED_DEVICE 0 60 #define BEACON_TYPE_SECURE_NETWORK 1 61 62 #define UNPROVISIONED_BEACON_INTERVAL_MS 5000 63 #define UNPROVISIONED_BEACON_LEN 23 64 65 #define SECURE_NETWORK_BEACON_INTERVAL_MIN_MS 10000 66 #define SECURE_NETWORK_BEACON_INTERVAL_MAX_MS 600000 67 #define SECURE_NETWORK_BEACON_LEN 22 68 69 // prototypes 70 static void mesh_secure_network_beacon_run(btstack_timer_source_t * ts); 71 72 // bearers 73 #ifdef ENABLE_MESH_GATT_BEARER 74 static hci_con_handle_t gatt_bearer_con_handle; 75 #endif 76 77 // beacon 78 static uint8_t mesh_beacon_data[29]; 79 static uint8_t mesh_beacon_len; 80 static btstack_timer_source_t beacon_timer; 81 static int beacon_timer_active; 82 83 // unprovisioned device beacon 84 #ifdef ENABLE_MESH_ADV_BEARER 85 static const uint8_t * beacon_device_uuid; 86 static uint16_t beacon_oob_information; 87 static uint32_t beacon_uri_hash; 88 static int beacon_send_device_beacon; 89 #endif 90 91 static btstack_packet_handler_t unprovisioned_device_beacon_handler; 92 93 // secure network beacon 94 static btstack_crypto_aes128_cmac_t mesh_secure_network_beacon_cmac_request; 95 static uint8_t mesh_secure_network_beacon_auth_value[16]; 96 static btstack_packet_handler_t mesh_secure_network_beacon_handler; 97 static int mesh_secure_network_beacon_active; 98 #ifdef ENABLE_MESH_ADV_BEARER 99 static uint8_t mesh_secure_network_beacon_validate_buffer[SECURE_NETWORK_BEACON_LEN]; 100 #endif 101 102 #ifdef ENABLE_MESH_ADV_BEARER 103 static void beacon_timer_handler(btstack_timer_source_t * ts){ 104 // restart timer 105 btstack_run_loop_set_timer(ts, UNPROVISIONED_BEACON_INTERVAL_MS); 106 btstack_run_loop_add_timer(ts); 107 beacon_timer_active = 1; 108 109 // setup beacon 110 mesh_beacon_len = UNPROVISIONED_BEACON_LEN; 111 mesh_beacon_data[0] = BEACON_TYPE_UNPROVISIONED_DEVICE; 112 memcpy(&mesh_beacon_data[1], beacon_device_uuid, 16); 113 big_endian_store_16(mesh_beacon_data, 17, beacon_oob_information); 114 big_endian_store_32(mesh_beacon_data, 19, beacon_uri_hash); 115 116 // request to send 117 beacon_send_device_beacon = 1; 118 adv_bearer_request_can_send_now_for_beacon(); 119 } 120 #endif 121 122 static void mesh_secure_network_beacon_auth_value_calculated(void * arg){ 123 mesh_subnet_t * mesh_subnet = (mesh_subnet_t *) arg; 124 125 memcpy(&mesh_beacon_data[14], mesh_secure_network_beacon_auth_value, 8); 126 mesh_beacon_len = SECURE_NETWORK_BEACON_LEN; 127 128 printf("Secure Network Beacon\n"); 129 printf("- "); 130 printf_hexdump(mesh_beacon_data, mesh_beacon_len); 131 132 mesh_secure_network_beacon_active = 0; 133 mesh_subnet->beacon_state = MESH_SECURE_NETWORK_BEACON_AUTH_VALUE; 134 135 mesh_secure_network_beacon_run(NULL); 136 } 137 138 static uint8_t mesh_secure_network_beacon_get_flags(mesh_subnet_t * mesh_subnet){ 139 uint8_t mesh_flags = 0; 140 if (mesh_subnet->key_refresh != MESH_KEY_REFRESH_NOT_ACTIVE){ 141 mesh_flags |= 1; 142 } 143 if (mesh_iv_update_active()){ 144 mesh_flags |= 2; 145 } 146 147 return mesh_flags; 148 } 149 150 static void mesh_secure_network_beacon_setup(mesh_subnet_t * mesh_subnet){ 151 mesh_beacon_data[0] = BEACON_TYPE_SECURE_NETWORK; 152 mesh_beacon_data[1] = mesh_secure_network_beacon_get_flags(mesh_subnet); 153 // TODO: pick correct key based on key refresh phase 154 155 memcpy(&mesh_beacon_data[2], mesh_subnet->old_key->network_id, 8); 156 big_endian_store_32(mesh_beacon_data, 10, mesh_get_iv_index()); 157 mesh_network_key_t * network_key = mesh_subnet_get_outgoing_network_key(mesh_subnet); 158 btstack_crypto_aes128_cmac_message(&mesh_secure_network_beacon_cmac_request, network_key->beacon_key, 13, 159 &mesh_beacon_data[1], mesh_secure_network_beacon_auth_value, &mesh_secure_network_beacon_auth_value_calculated, mesh_subnet); 160 } 161 162 static void mesh_secure_network_beacon_update_interval(mesh_subnet_t * subnet){ 163 uint32_t min_observation_period_ms = 2 * subnet->beacon_interval_ms; 164 uint32_t actual_observation_period = btstack_time_delta(btstack_run_loop_get_time_ms(), subnet->beacon_observation_start_ms); 165 166 // The Observation Period in seconds should typically be double the typical Beacon Interval. 167 if (actual_observation_period < min_observation_period_ms) return; 168 169 // Expected Number of Beacons (1 beacon per 10 seconds) 170 uint16_t expected_number_of_beacons = actual_observation_period / SECURE_NETWORK_BEACON_INTERVAL_MIN_MS; 171 172 // Beacon Interval = Observation Period * (Observed Number of Beacons + 1) / Expected Number of Beacons 173 uint32_t new_beacon_interval = actual_observation_period * (subnet->beacon_observation_counter + 1) / expected_number_of_beacons; 174 175 if (new_beacon_interval > SECURE_NETWORK_BEACON_INTERVAL_MAX_MS){ 176 new_beacon_interval = SECURE_NETWORK_BEACON_INTERVAL_MAX_MS; 177 } 178 else if (new_beacon_interval < SECURE_NETWORK_BEACON_INTERVAL_MIN_MS){ 179 new_beacon_interval = SECURE_NETWORK_BEACON_INTERVAL_MAX_MS; 180 } 181 subnet->beacon_interval_ms = new_beacon_interval; 182 log_info("New beacon interval %u seconds", (int) (subnet->beacon_interval_ms / 1000)); 183 } 184 185 static void mesh_secure_network_beacon_run(btstack_timer_source_t * ts){ 186 UNUSED(ts); 187 188 uint32_t next_timeout_ms = 0; 189 190 // iterate over all networks 191 mesh_subnet_iterator_t it; 192 mesh_subnet_iterator_init(&it); 193 while (mesh_subnet_iterator_has_more(&it)){ 194 mesh_subnet_t * subnet = mesh_subnet_iterator_get_next(&it); 195 switch (subnet->beacon_state){ 196 case MESH_SECURE_NETWORK_BEACON_W4_INTERVAL: 197 // update beacon interval 198 mesh_secure_network_beacon_update_interval(subnet); 199 200 if (mesh_foundation_beacon_get() == 0){ 201 // beacon off, continue observing 202 if (next_timeout_ms == 0 || next_timeout_ms > subnet->beacon_interval_ms){ 203 next_timeout_ms = subnet->beacon_interval_ms; 204 } 205 break; 206 } 207 208 // send new beacon 209 subnet->beacon_state = MESH_SECURE_NETWORK_BEACON_W2_AUTH_VALUE; 210 211 /** Explict Fall-through */ 212 213 case MESH_SECURE_NETWORK_BEACON_W2_AUTH_VALUE: 214 if (mesh_secure_network_beacon_active){ 215 // just try again in 10 ms 216 next_timeout_ms = 10; 217 break; 218 } 219 subnet->beacon_state = MESH_SECURE_NETWORK_BEACON_W4_AUTH_VALUE; 220 mesh_secure_network_beacon_active = 1; 221 mesh_secure_network_beacon_setup(subnet); 222 break; 223 224 case MESH_SECURE_NETWORK_BEACON_AUTH_VALUE: 225 226 #ifdef ENABLE_MESH_ADV_BEARER 227 subnet->beacon_state = MESH_SECURE_NETWORK_BEACON_W2_SEND_ADV; 228 adv_bearer_request_can_send_now_for_beacon(); 229 break; 230 #endif 231 subnet->beacon_state = MESH_SECURE_NETWORK_BEACON_ADV_SENT; 232 233 /** Explict Fall-through */ 234 235 case MESH_SECURE_NETWORK_BEACON_ADV_SENT: 236 237 #ifdef ENABLE_MESH_GATT_BEARER 238 if (gatt_bearer_con_handle != HCI_CON_HANDLE_INVALID && mesh_foundation_gatt_proxy_get() != 0){ 239 subnet->beacon_state = MESH_SECURE_NETWORK_BEACON_W2_SEND_GATT; 240 gatt_bearer_request_can_send_now_for_beacon(); 241 break; 242 } 243 #endif 244 subnet->beacon_state = MESH_SECURE_NETWORK_BEACON_GATT_SENT; 245 246 /** Explict Fall-through */ 247 248 case MESH_SECURE_NETWORK_BEACON_GATT_SENT: 249 // now, start listening for beacons 250 subnet->beacon_state = MESH_SECURE_NETWORK_BEACON_W4_INTERVAL; 251 // and request timeout 252 if (next_timeout_ms == 0 || next_timeout_ms > subnet->beacon_interval_ms){ 253 next_timeout_ms = subnet->beacon_interval_ms; 254 } 255 break; 256 257 default: 258 break; 259 } 260 } 261 262 if (beacon_timer_active){ 263 btstack_run_loop_remove_timer(&beacon_timer); 264 beacon_timer_active = 0; 265 } 266 267 // setup next run 268 if (next_timeout_ms == 0) return; 269 270 btstack_run_loop_set_timer(&beacon_timer, next_timeout_ms); 271 btstack_run_loop_set_timer_handler(&beacon_timer, mesh_secure_network_beacon_run); 272 btstack_run_loop_add_timer(&beacon_timer); 273 beacon_timer_active = 1; 274 } 275 276 #ifdef ENABLE_MESH_ADV_BEARER 277 static void beacon_handle_secure_beacon_auth_value_calculated(void * arg){ 278 UNUSED(arg); 279 280 // pass on, if auth value checks out 281 if (memcmp(&mesh_secure_network_beacon_validate_buffer[14], mesh_secure_network_beacon_auth_value, 8) == 0) { 282 if (mesh_secure_network_beacon_handler){ 283 (*mesh_secure_network_beacon_handler)(MESH_BEACON_PACKET, 0, mesh_secure_network_beacon_validate_buffer, SECURE_NETWORK_BEACON_LEN); 284 } 285 } 286 287 // done 288 mesh_secure_network_beacon_active = 0; 289 mesh_secure_network_beacon_run(NULL); 290 } 291 292 static void beacon_handle_secure_beacon(uint8_t * packet, uint16_t size){ 293 if (size != SECURE_NETWORK_BEACON_LEN) return; 294 295 // lookup subnet and netkey by network id 296 uint8_t * beacon_network_id = &packet[2]; 297 mesh_subnet_iterator_t it; 298 mesh_subnet_iterator_init(&it); 299 mesh_subnet_t * subnet = NULL; 300 mesh_network_key_t * network_key = NULL; 301 while (mesh_subnet_iterator_has_more(&it)){ 302 mesh_subnet_t * item = mesh_subnet_iterator_get_next(&it); 303 if (memcmp(item->old_key->network_id, beacon_network_id, 8) == 0 ) { 304 subnet = item; 305 network_key = item->old_key; 306 } 307 if (item->new_key != NULL && memcmp(item->new_key->network_id, beacon_network_id, 8) == 0 ) { 308 subnet = item; 309 network_key = item->new_key; 310 } 311 break; 312 } 313 if (subnet == NULL) return; 314 315 // count beacon 316 subnet->beacon_observation_counter++; 317 318 // check if new flags are set 319 uint8_t current_flags = mesh_secure_network_beacon_get_flags(subnet); 320 uint8_t new_flags = packet[1] & (~current_flags); 321 322 if (new_flags == 0) return; 323 324 // validate beacon - if crytpo ready 325 if (mesh_secure_network_beacon_active) return; 326 327 mesh_secure_network_beacon_active = 1; 328 memcpy(mesh_secure_network_beacon_validate_buffer, &packet[0], SECURE_NETWORK_BEACON_LEN); 329 330 btstack_crypto_aes128_cmac_message(&mesh_secure_network_beacon_cmac_request, network_key->beacon_key, 13, 331 &mesh_secure_network_beacon_validate_buffer[1], mesh_secure_network_beacon_auth_value, &beacon_handle_secure_beacon_auth_value_calculated, subnet); 332 } 333 334 static void beacon_handle_beacon_packet(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 335 log_info("beacon type %u", packet[0]); 336 switch (packet[0]){ 337 case BEACON_TYPE_UNPROVISIONED_DEVICE: 338 if (unprovisioned_device_beacon_handler){ 339 (*unprovisioned_device_beacon_handler)(packet_type, channel, packet, size); 340 } 341 break; 342 case BEACON_TYPE_SECURE_NETWORK: 343 beacon_handle_secure_beacon(packet, size); 344 break; 345 default: 346 break; 347 } 348 } 349 350 static void beacon_adv_packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 351 mesh_subnet_iterator_t it; 352 switch (packet_type){ 353 case HCI_EVENT_PACKET: 354 switch(packet[0]){ 355 case HCI_EVENT_MESH_META: 356 switch(packet[2]){ 357 case MESH_SUBEVENT_CAN_SEND_NOW: 358 if (beacon_send_device_beacon){ 359 beacon_send_device_beacon = 0; 360 adv_bearer_send_beacon(mesh_beacon_data, mesh_beacon_len); 361 break; 362 } 363 // secure beacon state machine 364 mesh_subnet_iterator_init(&it); 365 while (mesh_subnet_iterator_has_more(&it)){ 366 mesh_subnet_t * subnet = mesh_subnet_iterator_get_next(&it); 367 switch (subnet->beacon_state){ 368 case MESH_SECURE_NETWORK_BEACON_W2_SEND_ADV: 369 adv_bearer_send_beacon(mesh_beacon_data, mesh_beacon_len); 370 subnet->beacon_state = MESH_SECURE_NETWORK_BEACON_ADV_SENT; 371 mesh_secure_network_beacon_run(NULL); 372 break; 373 default: 374 break; 375 } 376 } 377 break; 378 default: 379 break; 380 } 381 break; 382 default: 383 break; 384 } 385 break; 386 case MESH_BEACON_PACKET: 387 beacon_handle_beacon_packet(packet_type, channel, packet, size); 388 break; 389 default: 390 break; 391 } 392 } 393 #endif 394 395 #ifdef ENABLE_MESH_GATT_BEARER 396 // handle MESH_SUBEVENT_PROXY_DISCONNECTED and MESH_SUBEVENT_CAN_SEND_NOW 397 static void beacon_gatt_handle_mesh_event(uint8_t mesh_subevent){ 398 mesh_subnet_iterator_t it; 399 mesh_subnet_iterator_init(&it); 400 while (mesh_subnet_iterator_has_more(&it)){ 401 mesh_subnet_t * subnet = mesh_subnet_iterator_get_next(&it); 402 switch (subnet->beacon_state){ 403 case MESH_SECURE_NETWORK_BEACON_W2_SEND_GATT: 404 // skip send on MESH_SUBEVENT_PROXY_DISCONNECTED 405 if (mesh_subevent == MESH_SUBEVENT_CAN_SEND_NOW){ 406 gatt_bearer_send_beacon(mesh_beacon_data, mesh_beacon_len); 407 } 408 subnet->beacon_state = MESH_SECURE_NETWORK_BEACON_GATT_SENT; 409 mesh_secure_network_beacon_run(NULL); 410 break; 411 default: 412 break; 413 } 414 } 415 416 } 417 418 static void beacon_gatt_packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 419 uint8_t mesh_subevent; 420 switch (packet_type){ 421 case HCI_EVENT_PACKET: 422 switch(packet[0]){ 423 case HCI_EVENT_MESH_META: 424 mesh_subevent = packet[2]; 425 switch(mesh_subevent){ 426 case MESH_SUBEVENT_PROXY_CONNECTED: 427 gatt_bearer_con_handle = mesh_subevent_proxy_connected_get_con_handle(packet); 428 break; 429 case MESH_SUBEVENT_PROXY_DISCONNECTED: 430 gatt_bearer_con_handle = HCI_CON_HANDLE_INVALID; 431 beacon_gatt_handle_mesh_event(mesh_subevent); 432 break; 433 case MESH_SUBEVENT_CAN_SEND_NOW: 434 beacon_gatt_handle_mesh_event(mesh_subevent); 435 break; 436 default: 437 break; 438 } 439 break; 440 default: 441 break; 442 } 443 break; 444 case MESH_BEACON_PACKET: 445 beacon_handle_beacon_packet(packet_type, channel, packet, size); 446 break; 447 default: 448 break; 449 } 450 } 451 #endif 452 453 void beacon_init(void){ 454 #ifdef ENABLE_MESH_ADV_BEARER 455 adv_bearer_register_for_beacon(&beacon_adv_packet_handler); 456 #endif 457 #ifdef ENABLE_MESH_GATT_BEARER 458 gatt_bearer_con_handle = HCI_CON_HANDLE_INVALID; 459 gatt_bearer_register_for_beacon(&beacon_gatt_packet_handler); 460 #endif 461 } 462 463 /** 464 * Start Unprovisioned Device Beacon 465 */ 466 void beacon_unprovisioned_device_start(const uint8_t * device_uuid, uint16_t oob_information){ 467 #ifdef ENABLE_MESH_ADV_BEARER 468 beacon_oob_information = oob_information; 469 if (device_uuid){ 470 beacon_device_uuid = device_uuid; 471 beacon_timer.process = &beacon_timer_handler; 472 beacon_timer_handler(&beacon_timer); 473 } 474 #endif 475 } 476 477 /** 478 * Stop Unprovisioned Device Beacon 479 */ 480 void beacon_unprovisioned_device_stop(void){ 481 #ifdef ENABLE_MESH_ADV_BEARER 482 btstack_run_loop_remove_timer(&beacon_timer); 483 beacon_timer_active = 0; 484 #endif 485 } 486 487 // secure network beacons 488 489 void beacon_secure_network_start(mesh_subnet_t * mesh_subnet){ 490 // default interval 491 mesh_subnet->beacon_interval_ms = SECURE_NETWORK_BEACON_INTERVAL_MIN_MS; 492 mesh_subnet->beacon_observation_start_ms = btstack_run_loop_get_time_ms(); 493 mesh_subnet->beacon_observation_counter = 0; 494 if (mesh_foundation_beacon_get()){ 495 mesh_subnet->beacon_state = MESH_SECURE_NETWORK_BEACON_W2_AUTH_VALUE; 496 } else { 497 mesh_subnet->beacon_state = MESH_SECURE_NETWORK_BEACON_GATT_SENT; 498 } 499 500 // start sending 501 mesh_secure_network_beacon_run(NULL); 502 } 503 504 // register handler 505 void beacon_register_for_unprovisioned_device_beacons(btstack_packet_handler_t packet_handler){ 506 unprovisioned_device_beacon_handler = packet_handler; 507 } 508 509 void beacon_register_for_secure_network_beacons(btstack_packet_handler_t packet_handler){ 510 mesh_secure_network_beacon_handler = packet_handler; 511 } 512