1 /****************************************************************************** 2 * 3 * Copyright (C) 1999-2012 Broadcom Corporation 4 * 5 * Licensed under the Apache License, Version 2.0 (the "License"); 6 * you may not use this file except in compliance with the License. 7 * You may obtain a copy of the License at: 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 * 17 ******************************************************************************/ 18 19 /****************************************************************************** 20 * 21 * This file contains functions for BLE address management. 22 * 23 ******************************************************************************/ 24 25 #include <base/bind.h> 26 #include <string.h> 27 28 #include "bt_types.h" 29 #include "btm_int.h" 30 #include "btu.h" 31 #include "device/include/controller.h" 32 #include "gap_api.h" 33 #include "hcimsgs.h" 34 35 #include "btm_ble_int.h" 36 #include "smp_api.h" 37 38 /******************************************************************************* 39 * 40 * Function btm_gen_resolve_paddr_cmpl 41 * 42 * Description This is callback functioin when resolvable private address 43 * generation is complete. 44 * 45 * Returns void 46 * 47 ******************************************************************************/ 48 static void btm_gen_resolve_paddr_cmpl(tSMP_ENC* p) { 49 tBTM_LE_RANDOM_CB* p_cb = &btm_cb.ble_ctr_cb.addr_mgnt_cb; 50 BTM_TRACE_EVENT("btm_gen_resolve_paddr_cmpl"); 51 52 if (p) { 53 /* set hash to be LSB of rpAddress */ 54 p_cb->private_addr.address[5] = p->param_buf[0]; 55 p_cb->private_addr.address[4] = p->param_buf[1]; 56 p_cb->private_addr.address[3] = p->param_buf[2]; 57 /* set it to controller */ 58 btm_ble_set_random_address(p_cb->private_addr); 59 60 p_cb->own_addr_type = BLE_ADDR_RANDOM; 61 62 /* start a periodical timer to refresh random addr */ 63 period_ms_t interval_ms = BTM_BLE_PRIVATE_ADDR_INT_MS; 64 #if (BTM_BLE_CONFORMANCE_TESTING == TRUE) 65 interval_ms = btm_cb.ble_ctr_cb.rpa_tout * 1000; 66 #endif 67 alarm_set_on_mloop(p_cb->refresh_raddr_timer, interval_ms, 68 btm_ble_refresh_raddr_timer_timeout, NULL); 69 } else { 70 /* random address set failure */ 71 BTM_TRACE_DEBUG("set random address failed"); 72 } 73 } 74 /******************************************************************************* 75 * 76 * Function btm_gen_resolve_paddr_low 77 * 78 * Description This function is called when random address has generate the 79 * random number base for low 3 byte bd address. 80 * 81 * Returns void 82 * 83 ******************************************************************************/ 84 void btm_gen_resolve_paddr_low(BT_OCTET8 rand) { 85 tBTM_LE_RANDOM_CB* p_cb = &btm_cb.ble_ctr_cb.addr_mgnt_cb; 86 tSMP_ENC output; 87 88 BTM_TRACE_EVENT("btm_gen_resolve_paddr_low"); 89 rand[2] &= (~BLE_RESOLVE_ADDR_MASK); 90 rand[2] |= BLE_RESOLVE_ADDR_MSB; 91 92 p_cb->private_addr.address[2] = rand[0]; 93 p_cb->private_addr.address[1] = rand[1]; 94 p_cb->private_addr.address[0] = rand[2]; 95 96 /* encrypt with ur IRK */ 97 if (!SMP_Encrypt(btm_cb.devcb.id_keys.irk, BT_OCTET16_LEN, rand, 3, 98 &output)) { 99 btm_gen_resolve_paddr_cmpl(NULL); 100 } else { 101 btm_gen_resolve_paddr_cmpl(&output); 102 } 103 } 104 /******************************************************************************* 105 * 106 * Function btm_gen_resolvable_private_addr 107 * 108 * Description This function generate a resolvable private address. 109 * 110 * Returns void 111 * 112 ******************************************************************************/ 113 void btm_gen_resolvable_private_addr(base::Callback<void(BT_OCTET8)> cb) { 114 BTM_TRACE_EVENT("%s", __func__); 115 /* generate 3B rand as BD LSB, SRK with it, get BD MSB */ 116 btsnd_hcic_ble_rand(std::move(cb)); 117 } 118 /******************************************************************************* 119 * 120 * Function btm_gen_non_resolve_paddr_cmpl 121 * 122 * Description This is the callback function when non-resolvable private 123 * function is generated and write to controller. 124 * 125 * Returns void 126 * 127 ******************************************************************************/ 128 static void btm_gen_non_resolve_paddr_cmpl(BT_OCTET8 rand) { 129 tBTM_LE_RANDOM_CB* p_cb = &btm_cb.ble_ctr_cb.addr_mgnt_cb; 130 tBTM_BLE_ADDR_CBACK* p_cback = p_cb->p_generate_cback; 131 void* p_data = p_cb->p; 132 uint8_t* pp; 133 RawAddress static_random; 134 135 BTM_TRACE_EVENT("btm_gen_non_resolve_paddr_cmpl"); 136 137 p_cb->p_generate_cback = NULL; 138 pp = rand; 139 STREAM_TO_BDADDR(static_random, pp); 140 /* mask off the 2 MSB */ 141 static_random.address[0] &= BLE_STATIC_PRIVATE_MSB_MASK; 142 143 /* report complete */ 144 if (p_cback) (*p_cback)(static_random, p_data); 145 } 146 /******************************************************************************* 147 * 148 * Function btm_gen_non_resolvable_private_addr 149 * 150 * Description This function generate a non-resolvable private address. 151 * 152 * 153 * Returns void 154 * 155 ******************************************************************************/ 156 void btm_gen_non_resolvable_private_addr(tBTM_BLE_ADDR_CBACK* p_cback, 157 void* p) { 158 tBTM_LE_RANDOM_CB* p_mgnt_cb = &btm_cb.ble_ctr_cb.addr_mgnt_cb; 159 160 BTM_TRACE_EVENT("btm_gen_non_resolvable_private_addr"); 161 162 if (p_mgnt_cb->p_generate_cback != NULL) return; 163 164 p_mgnt_cb->p_generate_cback = p_cback; 165 p_mgnt_cb->p = p; 166 btsnd_hcic_ble_rand(base::Bind(&btm_gen_non_resolve_paddr_cmpl)); 167 } 168 169 /******************************************************************************* 170 * Utility functions for Random address resolving 171 ******************************************************************************/ 172 /******************************************************************************* 173 * 174 * Function btm_ble_proc_resolve_x 175 * 176 * Description This function compares the X with random address 3 MSO bytes 177 * to find a match. 178 * 179 * Returns true on match, false otherwise 180 * 181 ******************************************************************************/ 182 static bool btm_ble_proc_resolve_x(const tSMP_ENC& encrypt_output, 183 const RawAddress& random_bda) { 184 BTM_TRACE_EVENT("btm_ble_proc_resolve_x"); 185 186 /* compare the hash with 3 LSB of bd address */ 187 uint8_t comp[3]; 188 comp[0] = random_bda.address[5]; 189 comp[1] = random_bda.address[4]; 190 comp[2] = random_bda.address[3]; 191 192 if (!memcmp(encrypt_output.param_buf, comp, 3)) { 193 BTM_TRACE_EVENT("match is found"); 194 return true; 195 } 196 197 return false; 198 } 199 200 /******************************************************************************* 201 * 202 * Function btm_ble_init_pseudo_addr 203 * 204 * Description This function is used to initialize pseudo address. 205 * If pseudo address is not available, use dummy address 206 * 207 * Returns true is updated; false otherwise. 208 * 209 ******************************************************************************/ 210 bool btm_ble_init_pseudo_addr(tBTM_SEC_DEV_REC* p_dev_rec, 211 const RawAddress& new_pseudo_addr) { 212 if (p_dev_rec->ble.pseudo_addr.IsEmpty()) { 213 p_dev_rec->ble.pseudo_addr = new_pseudo_addr; 214 return true; 215 } 216 217 return false; 218 } 219 220 /******************************************************************************* 221 * 222 * Function btm_ble_addr_resolvable 223 * 224 * Description This function checks if a RPA is resolvable by the device 225 * key. 226 * 227 * Returns true is resolvable; false otherwise. 228 * 229 ******************************************************************************/ 230 bool btm_ble_addr_resolvable(const RawAddress& rpa, 231 tBTM_SEC_DEV_REC* p_dev_rec) { 232 bool rt = false; 233 234 if (!BTM_BLE_IS_RESOLVE_BDA(rpa)) return rt; 235 236 uint8_t rand[3]; 237 tSMP_ENC output; 238 if ((p_dev_rec->device_type & BT_DEVICE_TYPE_BLE) && 239 (p_dev_rec->ble.key_type & BTM_LE_KEY_PID)) { 240 BTM_TRACE_DEBUG("%s try to resolve", __func__); 241 /* use the 3 MSB of bd address as prand */ 242 rand[0] = rpa.address[2]; 243 rand[1] = rpa.address[1]; 244 rand[2] = rpa.address[0]; 245 246 /* generate X = E irk(R0, R1, R2) and R is random address 3 LSO */ 247 SMP_Encrypt(p_dev_rec->ble.keys.irk, BT_OCTET16_LEN, &rand[0], 3, &output); 248 249 rand[0] = rpa.address[5]; 250 rand[1] = rpa.address[4]; 251 rand[2] = rpa.address[3]; 252 253 if (!memcmp(output.param_buf, &rand[0], 3)) { 254 btm_ble_init_pseudo_addr(p_dev_rec, rpa); 255 rt = true; 256 } 257 } 258 return rt; 259 } 260 261 /******************************************************************************* 262 * 263 * Function btm_ble_match_random_bda 264 * 265 * Description This function match the random address to the appointed 266 * device record, starting from calculating IRK. If the record 267 * index exceeds the maximum record number, matching failed and 268 * send a callback. 269 * 270 * Returns None. 271 * 272 ******************************************************************************/ 273 static bool btm_ble_match_random_bda(void* data, void* context) { 274 RawAddress* random_bda = (RawAddress*)context; 275 /* use the 3 MSB of bd address as prand */ 276 277 uint8_t rand[3]; 278 rand[0] = random_bda->address[2]; 279 rand[1] = random_bda->address[1]; 280 rand[2] = random_bda->address[0]; 281 282 BTM_TRACE_EVENT("%s next iteration", __func__); 283 284 tSMP_ENC output; 285 tBTM_SEC_DEV_REC* p_dev_rec = static_cast<tBTM_SEC_DEV_REC*>(data); 286 287 BTM_TRACE_DEBUG("sec_flags = %02x device_type = %d", p_dev_rec->sec_flags, 288 p_dev_rec->device_type); 289 290 if (!(p_dev_rec->device_type & BT_DEVICE_TYPE_BLE) || 291 !(p_dev_rec->ble.key_type & BTM_LE_KEY_PID)) 292 return true; 293 294 /* generate X = E irk(R0, R1, R2) and R is random address 3 LSO */ 295 SMP_Encrypt(p_dev_rec->ble.keys.irk, BT_OCTET16_LEN, &rand[0], 3, &output); 296 // if it was match, finish iteration, otherwise continue 297 return !btm_ble_proc_resolve_x(output, *random_bda); 298 } 299 300 /******************************************************************************* 301 * 302 * Function btm_ble_resolve_random_addr 303 * 304 * Description This function is called to resolve a random address. 305 * 306 * Returns pointer to the security record of the device whom a random 307 * address is matched to. 308 * 309 ******************************************************************************/ 310 tBTM_SEC_DEV_REC* btm_ble_resolve_random_addr(const RawAddress& random_bda) { 311 BTM_TRACE_EVENT("%s", __func__); 312 313 /* start to resolve random address */ 314 /* check for next security record */ 315 316 list_node_t* n = list_foreach(btm_cb.sec_dev_rec, btm_ble_match_random_bda, 317 (void*)&random_bda); 318 tBTM_SEC_DEV_REC* p_dev_rec = nullptr; 319 if (n != nullptr) p_dev_rec = static_cast<tBTM_SEC_DEV_REC*>(list_node(n)); 320 321 BTM_TRACE_EVENT("%s: %sresolved", __func__, 322 (p_dev_rec == nullptr ? "not " : "")); 323 return p_dev_rec; 324 } 325 326 /******************************************************************************* 327 * address mapping between pseudo address and real connection address 328 ******************************************************************************/ 329 /******************************************************************************* 330 * 331 * Function btm_find_dev_by_identity_addr 332 * 333 * Description find the security record whose LE static address is matching 334 * 335 ******************************************************************************/ 336 tBTM_SEC_DEV_REC* btm_find_dev_by_identity_addr(const RawAddress& bd_addr, 337 uint8_t addr_type) { 338 #if (BLE_PRIVACY_SPT == TRUE) 339 list_node_t* end = list_end(btm_cb.sec_dev_rec); 340 for (list_node_t* node = list_begin(btm_cb.sec_dev_rec); node != end; 341 node = list_next(node)) { 342 tBTM_SEC_DEV_REC* p_dev_rec = 343 static_cast<tBTM_SEC_DEV_REC*>(list_node(node)); 344 if (p_dev_rec->ble.static_addr == bd_addr) { 345 if ((p_dev_rec->ble.static_addr_type & (~BLE_ADDR_TYPE_ID_BIT)) != 346 (addr_type & (~BLE_ADDR_TYPE_ID_BIT))) 347 BTM_TRACE_WARNING( 348 "%s find pseudo->random match with diff addr type: %d vs %d", 349 __func__, p_dev_rec->ble.static_addr_type, addr_type); 350 351 /* found the match */ 352 return p_dev_rec; 353 } 354 } 355 #endif 356 357 return NULL; 358 } 359 360 /******************************************************************************* 361 * 362 * Function btm_identity_addr_to_random_pseudo 363 * 364 * Description This function map a static BD address to a pseudo random 365 * address in security database. 366 * 367 ******************************************************************************/ 368 bool btm_identity_addr_to_random_pseudo(RawAddress* bd_addr, 369 uint8_t* p_addr_type, bool refresh) { 370 #if (BLE_PRIVACY_SPT == TRUE) 371 tBTM_SEC_DEV_REC* p_dev_rec = 372 btm_find_dev_by_identity_addr(*bd_addr, *p_addr_type); 373 374 BTM_TRACE_EVENT("%s", __func__); 375 /* evt reported on static address, map static address to random pseudo */ 376 if (p_dev_rec != NULL) { 377 /* if RPA offloading is supported, or 4.2 controller, do RPA refresh */ 378 if (refresh && 379 controller_get_interface()->get_ble_resolving_list_max_size() != 0) 380 btm_ble_read_resolving_list_entry(p_dev_rec); 381 382 /* assign the original address to be the current report address */ 383 if (!btm_ble_init_pseudo_addr(p_dev_rec, *bd_addr)) 384 *bd_addr = p_dev_rec->ble.pseudo_addr; 385 386 *p_addr_type = p_dev_rec->ble.ble_addr_type; 387 return true; 388 } 389 #endif 390 return false; 391 } 392 393 /******************************************************************************* 394 * 395 * Function btm_random_pseudo_to_identity_addr 396 * 397 * Description This function map a random pseudo address to a public 398 * address. random_pseudo is input and output parameter 399 * 400 ******************************************************************************/ 401 bool btm_random_pseudo_to_identity_addr(RawAddress* random_pseudo, 402 uint8_t* p_static_addr_type) { 403 #if (BLE_PRIVACY_SPT == TRUE) 404 tBTM_SEC_DEV_REC* p_dev_rec = btm_find_dev(*random_pseudo); 405 406 if (p_dev_rec != NULL) { 407 if (p_dev_rec->ble.in_controller_list & BTM_RESOLVING_LIST_BIT) { 408 *p_static_addr_type = p_dev_rec->ble.static_addr_type; 409 *random_pseudo = p_dev_rec->ble.static_addr; 410 if (controller_get_interface()->supports_ble_privacy()) 411 *p_static_addr_type |= BLE_ADDR_TYPE_ID_BIT; 412 return true; 413 } 414 } 415 #endif 416 return false; 417 } 418 419 /******************************************************************************* 420 * 421 * Function btm_ble_refresh_peer_resolvable_private_addr 422 * 423 * Description This function refresh the currently used resolvable remote 424 * private address into security database and set active 425 * connection address. 426 * 427 ******************************************************************************/ 428 void btm_ble_refresh_peer_resolvable_private_addr(const RawAddress& pseudo_bda, 429 const RawAddress& rpa, 430 uint8_t rra_type) { 431 #if (BLE_PRIVACY_SPT == TRUE) 432 uint8_t rra_dummy = false; 433 if (rpa.IsEmpty()) rra_dummy = true; 434 435 /* update security record here, in adv event or connection complete process */ 436 tBTM_SEC_DEV_REC* p_sec_rec = btm_find_dev(pseudo_bda); 437 if (p_sec_rec != NULL) { 438 p_sec_rec->ble.cur_rand_addr = rpa; 439 440 /* unknown, if dummy address, set to static */ 441 if (rra_type == BTM_BLE_ADDR_PSEUDO) 442 p_sec_rec->ble.active_addr_type = 443 rra_dummy ? BTM_BLE_ADDR_STATIC : BTM_BLE_ADDR_RRA; 444 else 445 p_sec_rec->ble.active_addr_type = rra_type; 446 } else { 447 BTM_TRACE_ERROR("No matching known device in record"); 448 return; 449 } 450 451 BTM_TRACE_DEBUG("%s: active_addr_type: %d ", __func__, 452 p_sec_rec->ble.active_addr_type); 453 454 /* connection refresh remote address */ 455 tACL_CONN* p_acl = btm_bda_to_acl(p_sec_rec->bd_addr, BT_TRANSPORT_LE); 456 if (p_acl == NULL) 457 p_acl = btm_bda_to_acl(p_sec_rec->ble.pseudo_addr, BT_TRANSPORT_LE); 458 459 if (p_acl != NULL) { 460 if (rra_type == BTM_BLE_ADDR_PSEUDO) { 461 /* use static address, resolvable_private_addr is empty */ 462 if (rra_dummy) { 463 p_acl->active_remote_addr_type = p_sec_rec->ble.static_addr_type; 464 p_acl->active_remote_addr = p_sec_rec->ble.static_addr; 465 } else { 466 p_acl->active_remote_addr_type = BLE_ADDR_RANDOM; 467 p_acl->active_remote_addr = rpa; 468 } 469 } else { 470 p_acl->active_remote_addr_type = rra_type; 471 p_acl->active_remote_addr = rpa; 472 } 473 474 BTM_TRACE_DEBUG("p_acl->active_remote_addr_type: %d ", 475 p_acl->active_remote_addr_type); 476 VLOG(1) << __func__ << " conn_addr: " << p_acl->active_remote_addr; 477 } 478 #endif 479 } 480 481 /******************************************************************************* 482 * 483 * Function btm_ble_refresh_local_resolvable_private_addr 484 * 485 * Description This function refresh the currently used resolvable private 486 * address for the active link to the remote device 487 * 488 ******************************************************************************/ 489 void btm_ble_refresh_local_resolvable_private_addr( 490 const RawAddress& pseudo_addr, const RawAddress& local_rpa) { 491 #if (BLE_PRIVACY_SPT == TRUE) 492 tACL_CONN* p = btm_bda_to_acl(pseudo_addr, BT_TRANSPORT_LE); 493 494 if (p != NULL) { 495 if (btm_cb.ble_ctr_cb.privacy_mode != BTM_PRIVACY_NONE) { 496 p->conn_addr_type = BLE_ADDR_RANDOM; 497 if (!local_rpa.IsEmpty()) 498 p->conn_addr = local_rpa; 499 else 500 p->conn_addr = btm_cb.ble_ctr_cb.addr_mgnt_cb.private_addr; 501 } else { 502 p->conn_addr_type = BLE_ADDR_PUBLIC; 503 p->conn_addr = *controller_get_interface()->get_address(); 504 } 505 } 506 #endif 507 } 508