1 /* 2 * Copyright (C) 2012 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 /* 18 * A service that exchanges time synchronization information between 19 * a master that defines a timeline and clients that follow the timeline. 20 */ 21 22 #define LOG_TAG "common_time" 23 #include <utils/Log.h> 24 25 #include <arpa/inet.h> 26 #include <assert.h> 27 #include <fcntl.h> 28 #include <linux/if_ether.h> 29 #include <net/if.h> 30 #include <net/if_arp.h> 31 #include <netinet/ip.h> 32 #include <poll.h> 33 #include <stdio.h> 34 #include <sys/eventfd.h> 35 #include <sys/ioctl.h> 36 #include <sys/stat.h> 37 #include <sys/types.h> 38 #include <sys/socket.h> 39 40 #include <common_time/local_clock.h> 41 #include <binder/IPCThreadState.h> 42 #include <binder/ProcessState.h> 43 #include <utils/Timers.h> 44 45 #include "common_clock_service.h" 46 #include "common_time_config_service.h" 47 #include "common_time_server.h" 48 #include "common_time_server_packets.h" 49 #include "clock_recovery.h" 50 #include "common_clock.h" 51 52 #define MAX_INT ((int)0x7FFFFFFF) 53 54 namespace android { 55 56 const char* CommonTimeServer::kDefaultMasterElectionAddr = "239.195.128.88"; 57 const uint16_t CommonTimeServer::kDefaultMasterElectionPort = 8887; 58 const uint64_t CommonTimeServer::kDefaultSyncGroupID = 0; 59 const uint8_t CommonTimeServer::kDefaultMasterPriority = 1; 60 const uint32_t CommonTimeServer::kDefaultMasterAnnounceIntervalMs = 10000; 61 const uint32_t CommonTimeServer::kDefaultSyncRequestIntervalMs = 1000; 62 const uint32_t CommonTimeServer::kDefaultPanicThresholdUsec = 50000; 63 const bool CommonTimeServer::kDefaultAutoDisable = true; 64 const int CommonTimeServer::kSetupRetryTimeoutMs = 30000; 65 const int64_t CommonTimeServer::kNoGoodDataPanicThresholdUsec = 600000000ll; 66 const uint32_t CommonTimeServer::kRTTDiscardPanicThreshMultiplier = 5; 67 68 // timeout value representing an infinite timeout 69 const int CommonTimeServer::kInfiniteTimeout = -1; 70 71 /*** Initial state constants ***/ 72 73 // number of WhoIsMaster attempts sent before giving up 74 const int CommonTimeServer::kInitial_NumWhoIsMasterRetries = 6; 75 76 // timeout used when waiting for a response to a WhoIsMaster request 77 const int CommonTimeServer::kInitial_WhoIsMasterTimeoutMs = 500; 78 79 /*** Client state constants ***/ 80 81 // number of sync requests that can fail before a client assumes its master 82 // is dead 83 const int CommonTimeServer::kClient_NumSyncRequestRetries = 10; 84 85 /*** Master state constants ***/ 86 87 /*** Ronin state constants ***/ 88 89 // number of WhoIsMaster attempts sent before declaring ourselves master 90 const int CommonTimeServer::kRonin_NumWhoIsMasterRetries = 20; 91 92 // timeout used when waiting for a response to a WhoIsMaster request 93 const int CommonTimeServer::kRonin_WhoIsMasterTimeoutMs = 500; 94 95 /*** WaitForElection state constants ***/ 96 97 // how long do we wait for an announcement from a master before 98 // trying another election? 99 const int CommonTimeServer::kWaitForElection_TimeoutMs = 12500; 100 101 CommonTimeServer::CommonTimeServer() 102 : Thread(false) 103 , mState(ICommonClock::STATE_INITIAL) 104 , mClockRecovery(&mLocalClock, &mCommonClock) 105 , mSocket(-1) 106 , mLastPacketRxLocalTime(0) 107 , mTimelineID(ICommonClock::kInvalidTimelineID) 108 , mClockSynced(false) 109 , mCommonClockHasClients(false) 110 , mInitial_WhoIsMasterRequestTimeouts(0) 111 , mClient_MasterDeviceID(0) 112 , mClient_MasterDevicePriority(0) 113 , mRonin_WhoIsMasterRequestTimeouts(0) { 114 // zero out sync stats 115 resetSyncStats(); 116 117 // Setup the master election endpoint to use the default. 118 struct sockaddr_in* meep = 119 reinterpret_cast<struct sockaddr_in*>(&mMasterElectionEP); 120 memset(&mMasterElectionEP, 0, sizeof(mMasterElectionEP)); 121 inet_aton(kDefaultMasterElectionAddr, &meep->sin_addr); 122 meep->sin_family = AF_INET; 123 meep->sin_port = htons(kDefaultMasterElectionPort); 124 125 // Zero out the master endpoint. 126 memset(&mMasterEP, 0, sizeof(mMasterEP)); 127 mMasterEPValid = false; 128 mBindIfaceValid = false; 129 setForceLowPriority(false); 130 131 // Set all remaining configuration parameters to their defaults. 132 mDeviceID = 0; 133 mSyncGroupID = kDefaultSyncGroupID; 134 mMasterPriority = kDefaultMasterPriority; 135 mMasterAnnounceIntervalMs = kDefaultMasterAnnounceIntervalMs; 136 mSyncRequestIntervalMs = kDefaultSyncRequestIntervalMs; 137 mPanicThresholdUsec = kDefaultPanicThresholdUsec; 138 mAutoDisable = kDefaultAutoDisable; 139 140 // Create the eventfd we will use to signal our thread to wake up when 141 // needed. 142 mWakeupThreadFD = eventfd(0, EFD_NONBLOCK); 143 144 // seed the random number generator (used to generated timeline IDs) 145 srand48(static_cast<unsigned int>(systemTime())); 146 } 147 148 CommonTimeServer::~CommonTimeServer() { 149 shutdownThread(); 150 151 // No need to grab the lock here. We are in the destructor; if the the user 152 // has a thread in any of the APIs while the destructor is being called, 153 // there is a threading problem a the application level we cannot reasonably 154 // do anything about. 155 cleanupSocket_l(); 156 157 if (mWakeupThreadFD >= 0) { 158 close(mWakeupThreadFD); 159 mWakeupThreadFD = -1; 160 } 161 } 162 163 bool CommonTimeServer::startServices() { 164 // start the ICommonClock service 165 mICommonClock = CommonClockService::instantiate(*this); 166 if (mICommonClock == NULL) 167 return false; 168 169 // start the ICommonTimeConfig service 170 mICommonTimeConfig = CommonTimeConfigService::instantiate(*this); 171 if (mICommonTimeConfig == NULL) 172 return false; 173 174 return true; 175 } 176 177 bool CommonTimeServer::threadLoop() { 178 // Register our service interfaces. 179 if (!startServices()) 180 return false; 181 182 // Hold the lock while we are in the main thread loop. It will release the 183 // lock when it blocks, and hold the lock at all other times. 184 mLock.lock(); 185 runStateMachine_l(); 186 mLock.unlock(); 187 188 IPCThreadState::self()->stopProcess(); 189 return false; 190 } 191 192 bool CommonTimeServer::runStateMachine_l() { 193 if (!mLocalClock.initCheck()) 194 return false; 195 196 if (!mCommonClock.init(mLocalClock.getLocalFreq())) 197 return false; 198 199 // Enter the initial state. 200 becomeInitial("startup"); 201 202 // run the state machine 203 while (!exitPending()) { 204 struct pollfd pfds[2]; 205 int rc; 206 int eventCnt = 0; 207 int64_t wakeupTime; 208 209 // We are always interested in our wakeup FD. 210 pfds[eventCnt].fd = mWakeupThreadFD; 211 pfds[eventCnt].events = POLLIN; 212 pfds[eventCnt].revents = 0; 213 eventCnt++; 214 215 // If we have a valid socket, then we are interested in what it has to 216 // say as well. 217 if (mSocket >= 0) { 218 pfds[eventCnt].fd = mSocket; 219 pfds[eventCnt].events = POLLIN; 220 pfds[eventCnt].revents = 0; 221 eventCnt++; 222 } 223 224 // Note, we were holding mLock when this function was called. We 225 // release it only while we are blocking and hold it at all other times. 226 mLock.unlock(); 227 rc = poll(pfds, eventCnt, mCurTimeout.msecTillTimeout()); 228 wakeupTime = mLocalClock.getLocalTime(); 229 mLock.lock(); 230 231 // Is it time to shutdown? If so, don't hesitate... just do it. 232 if (exitPending()) 233 break; 234 235 // Did the poll fail? This should never happen and is fatal if it does. 236 if (rc < 0) { 237 ALOGE("%s:%d poll failed", __PRETTY_FUNCTION__, __LINE__); 238 return false; 239 } 240 241 if (rc == 0) 242 mCurTimeout.setTimeout(kInfiniteTimeout); 243 244 // Were we woken up on purpose? If so, clear the eventfd with a read. 245 if (pfds[0].revents) 246 clearPendingWakeupEvents_l(); 247 248 // Is out bind address dirty? If so, clean up our socket (if any). 249 // Alternatively, do we have an active socket but should be auto 250 // disabled? If so, release the socket and enter the proper sync state. 251 bool droppedSocket = false; 252 if (mBindIfaceDirty || ((mSocket >= 0) && shouldAutoDisable())) { 253 cleanupSocket_l(); 254 mBindIfaceDirty = false; 255 droppedSocket = true; 256 } 257 258 // Do we not have a socket but should have one? If so, try to set one 259 // up. 260 if ((mSocket < 0) && mBindIfaceValid && !shouldAutoDisable()) { 261 if (setupSocket_l()) { 262 // Success! We are now joining a new network (either coming 263 // from no network, or coming from a potentially different 264 // network). Force our priority to be lower so that we defer to 265 // any other masters which may already be on the network we are 266 // joining. Later, when we enter either the client or the 267 // master state, we will clear this flag and go back to our 268 // normal election priority. 269 setForceLowPriority(true); 270 switch (mState) { 271 // If we were in initial (whether we had a immediately 272 // before this network or not) we want to simply reset the 273 // system and start again. Forcing a transition from 274 // INITIAL to INITIAL should do the job. 275 case CommonClockService::STATE_INITIAL: 276 becomeInitial("bound interface"); 277 break; 278 279 // If we were in the master state, then either we were the 280 // master in a no-network situation, or we were the master 281 // of a different network and have moved to a new interface. 282 // In either case, immediately transition to Ronin at low 283 // priority. If there is no one in the network we just 284 // joined, we will become master soon enough. If there is, 285 // we want to be certain to defer master status to the 286 // existing timeline currently running on the network. 287 // 288 case CommonClockService::STATE_MASTER: 289 becomeRonin("leaving networkless mode"); 290 break; 291 292 // If we were in any other state (CLIENT, RONIN, or 293 // WAIT_FOR_ELECTION) then we must be moving from one 294 // network to another. We have lost our old master; 295 // transition to RONIN in an attempt to find a new master. 296 // If there are none out there, we will just assume 297 // responsibility for the timeline we used to be a client 298 // of. 299 default: 300 becomeRonin("bound interface"); 301 break; 302 } 303 } else { 304 // That's odd... we failed to set up our socket. This could be 305 // due to some transient network change which will work itself 306 // out shortly; schedule a retry attempt in the near future. 307 mCurTimeout.setTimeout(kSetupRetryTimeoutMs); 308 } 309 310 // One way or the other, we don't have any data to process at this 311 // point (since we just tried to bulid a new socket). Loop back 312 // around and wait for the next thing to do. 313 continue; 314 } else if (droppedSocket) { 315 // We just lost our socket, and for whatever reason (either no 316 // config, or auto disable engaged) we are not supposed to rebuild 317 // one at this time. We are not going to rebuild our socket until 318 // something about our config/auto-disabled status changes, so we 319 // are basically in network-less mode. If we are already in either 320 // INITIAL or MASTER, just stay there until something changes. If 321 // we are in any other state (CLIENT, RONIN or WAIT_FOR_ELECTION), 322 // then transition to either INITIAL or MASTER depending on whether 323 // or not our timeline is valid. 324 ALOGI("Entering networkless mode interface is %s, " 325 "shouldAutoDisable = %s", 326 mBindIfaceValid ? "valid" : "invalid", 327 shouldAutoDisable() ? "true" : "false"); 328 if ((mState != ICommonClock::STATE_INITIAL) && 329 (mState != ICommonClock::STATE_MASTER)) { 330 if (mTimelineID == ICommonClock::kInvalidTimelineID) 331 becomeInitial("network-less mode"); 332 else 333 becomeMaster("network-less mode"); 334 } 335 336 continue; 337 } 338 339 // Did we wakeup with no signalled events across all of our FDs? If so, 340 // we must have hit our timeout. 341 if (rc == 0) { 342 if (!handleTimeout()) 343 ALOGE("handleTimeout failed"); 344 continue; 345 } 346 347 // Does our socket have data for us (assuming we still have one, we 348 // may have RXed a packet at the same time as a config change telling us 349 // to shut our socket down)? If so, process its data. 350 if ((mSocket >= 0) && (eventCnt > 1) && (pfds[1].revents)) { 351 mLastPacketRxLocalTime = wakeupTime; 352 if (!handlePacket()) 353 ALOGE("handlePacket failed"); 354 } 355 } 356 357 cleanupSocket_l(); 358 return true; 359 } 360 361 void CommonTimeServer::clearPendingWakeupEvents_l() { 362 int64_t tmp; 363 read(mWakeupThreadFD, &tmp, sizeof(tmp)); 364 } 365 366 void CommonTimeServer::wakeupThread_l() { 367 int64_t tmp = 1; 368 write(mWakeupThreadFD, &tmp, sizeof(tmp)); 369 } 370 371 void CommonTimeServer::cleanupSocket_l() { 372 if (mSocket >= 0) { 373 close(mSocket); 374 mSocket = -1; 375 } 376 } 377 378 void CommonTimeServer::shutdownThread() { 379 // Flag the work thread for shutdown. 380 this->requestExit(); 381 382 // Signal the thread in case its sleeping. 383 mLock.lock(); 384 wakeupThread_l(); 385 mLock.unlock(); 386 387 // Wait for the thread to exit. 388 this->join(); 389 } 390 391 bool CommonTimeServer::setupSocket_l() { 392 int rc; 393 bool ret_val = false; 394 struct sockaddr_in* ipv4_addr = NULL; 395 char masterElectionEPStr[64]; 396 const int one = 1; 397 398 // This should never be needed, but if we happened to have an old socket 399 // lying around, be sure to not leak it before proceeding. 400 cleanupSocket_l(); 401 402 // If we don't have a valid endpoint to bind to, then how did we get here in 403 // the first place? Regardless, we know that we are going to fail to bind, 404 // so don't even try. 405 if (!mBindIfaceValid) 406 return false; 407 408 sockaddrToString(mMasterElectionEP, true, masterElectionEPStr, 409 sizeof(masterElectionEPStr)); 410 ALOGI("Building socket :: bind = %s master election = %s", 411 mBindIface.string(), masterElectionEPStr); 412 413 // TODO: add proper support for IPv6. Right now, we block IPv6 addresses at 414 // the configuration interface level. 415 if (AF_INET != mMasterElectionEP.ss_family) { 416 ALOGW("TODO: add proper IPv6 support"); 417 goto bailout; 418 } 419 420 // open a UDP socket for the timeline serivce 421 mSocket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); 422 if (mSocket < 0) { 423 ALOGE("Failed to create socket (errno = %d)", errno); 424 goto bailout; 425 } 426 427 // Bind to the selected interface using Linux's spiffy SO_BINDTODEVICE. 428 struct ifreq ifr; 429 memset(&ifr, 0, sizeof(ifr)); 430 snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s", mBindIface.string()); 431 ifr.ifr_name[sizeof(ifr.ifr_name) - 1] = 0; 432 rc = setsockopt(mSocket, SOL_SOCKET, SO_BINDTODEVICE, 433 (void *)&ifr, sizeof(ifr)); 434 if (rc) { 435 ALOGE("Failed to bind socket at to interface %s (errno = %d)", 436 ifr.ifr_name, errno); 437 goto bailout; 438 } 439 440 // Bind our socket to INADDR_ANY and the master election port. The 441 // interface binding we made using SO_BINDTODEVICE should limit us to 442 // traffic only on the interface we are interested in. We need to bind to 443 // INADDR_ANY and the specific master election port in order to be able to 444 // receive both unicast traffic and master election multicast traffic with 445 // just a single socket. 446 struct sockaddr_in bindAddr; 447 ipv4_addr = reinterpret_cast<struct sockaddr_in*>(&mMasterElectionEP); 448 memcpy(&bindAddr, ipv4_addr, sizeof(bindAddr)); 449 bindAddr.sin_addr.s_addr = INADDR_ANY; 450 rc = bind(mSocket, 451 reinterpret_cast<const sockaddr *>(&bindAddr), 452 sizeof(bindAddr)); 453 if (rc) { 454 ALOGE("Failed to bind socket to port %hu (errno = %d)", 455 ntohs(bindAddr.sin_port), errno); 456 goto bailout; 457 } 458 459 if (0xE0000000 == (ntohl(ipv4_addr->sin_addr.s_addr) & 0xF0000000)) { 460 // If our master election endpoint is a multicast address, be sure to join 461 // the multicast group. 462 struct ip_mreq mreq; 463 mreq.imr_multiaddr = ipv4_addr->sin_addr; 464 mreq.imr_interface.s_addr = htonl(INADDR_ANY); 465 rc = setsockopt(mSocket, IPPROTO_IP, IP_ADD_MEMBERSHIP, 466 &mreq, sizeof(mreq)); 467 if (rc == -1) { 468 ALOGE("Failed to join multicast group at %s. (errno = %d)", 469 masterElectionEPStr, errno); 470 goto bailout; 471 } 472 473 // disable loopback of multicast packets 474 const int zero = 0; 475 rc = setsockopt(mSocket, IPPROTO_IP, IP_MULTICAST_LOOP, 476 &zero, sizeof(zero)); 477 if (rc == -1) { 478 ALOGE("Failed to disable multicast loopback (errno = %d)", errno); 479 goto bailout; 480 } 481 } else 482 if (ntohl(ipv4_addr->sin_addr.s_addr) != 0xFFFFFFFF) { 483 // If the master election address is neither broadcast, nor multicast, 484 // then we are misconfigured. The config API layer should prevent this 485 // from ever happening. 486 goto bailout; 487 } 488 489 // Set the TTL of sent packets to 1. (Time protocol sync should never leave 490 // the local subnet) 491 rc = setsockopt(mSocket, IPPROTO_IP, IP_TTL, &one, sizeof(one)); 492 if (rc == -1) { 493 ALOGE("Failed to set TTL to %d (errno = %d)", one, errno); 494 goto bailout; 495 } 496 497 // get the device's unique ID 498 if (!assignDeviceID()) 499 goto bailout; 500 501 ret_val = true; 502 503 bailout: 504 if (!ret_val) 505 cleanupSocket_l(); 506 return ret_val; 507 } 508 509 // generate a unique device ID that can be used for arbitration 510 bool CommonTimeServer::assignDeviceID() { 511 if (!mBindIfaceValid) 512 return false; 513 514 struct ifreq ifr; 515 memset(&ifr, 0, sizeof(ifr)); 516 ifr.ifr_addr.sa_family = AF_INET; 517 strlcpy(ifr.ifr_name, mBindIface.string(), IFNAMSIZ); 518 519 int rc = ioctl(mSocket, SIOCGIFHWADDR, &ifr); 520 if (rc) { 521 ALOGE("%s:%d ioctl failed", __PRETTY_FUNCTION__, __LINE__); 522 return false; 523 } 524 525 if (ifr.ifr_addr.sa_family != ARPHRD_ETHER) { 526 ALOGE("%s:%d got non-Ethernet address", __PRETTY_FUNCTION__, __LINE__); 527 return false; 528 } 529 530 mDeviceID = 0; 531 for (int i = 0; i < ETH_ALEN; i++) { 532 mDeviceID = (mDeviceID << 8) | ifr.ifr_hwaddr.sa_data[i]; 533 } 534 535 return true; 536 } 537 538 // generate a new timeline ID 539 void CommonTimeServer::assignTimelineID() { 540 do { 541 mTimelineID = (static_cast<uint64_t>(lrand48()) << 32) 542 | static_cast<uint64_t>(lrand48()); 543 } while (mTimelineID == ICommonClock::kInvalidTimelineID); 544 } 545 546 // Select a preference between the device IDs of two potential masters. 547 // Returns true if the first ID wins, or false if the second ID wins. 548 bool CommonTimeServer::arbitrateMaster( 549 uint64_t deviceID1, uint8_t devicePrio1, 550 uint64_t deviceID2, uint8_t devicePrio2) { 551 return ((devicePrio1 > devicePrio2) || 552 ((devicePrio1 == devicePrio2) && (deviceID1 > deviceID2))); 553 } 554 555 bool CommonTimeServer::handlePacket() { 556 uint8_t buf[256]; 557 struct sockaddr_storage srcAddr; 558 socklen_t srcAddrLen = sizeof(srcAddr); 559 560 ssize_t recvBytes = recvfrom( 561 mSocket, buf, sizeof(buf), 0, 562 reinterpret_cast<const sockaddr *>(&srcAddr), &srcAddrLen); 563 564 if (recvBytes < 0) { 565 ALOGE("%s:%d recvfrom failed", __PRETTY_FUNCTION__, __LINE__); 566 return false; 567 } 568 569 UniversalTimeServicePacket pkt; 570 recvBytes = pkt.deserializePacket(buf, recvBytes, mSyncGroupID); 571 if (recvBytes < 0) 572 return false; 573 574 bool result; 575 switch (pkt.packetType) { 576 case TIME_PACKET_WHO_IS_MASTER_REQUEST: 577 result = handleWhoIsMasterRequest(&pkt.p.who_is_master_request, 578 srcAddr); 579 break; 580 581 case TIME_PACKET_WHO_IS_MASTER_RESPONSE: 582 result = handleWhoIsMasterResponse(&pkt.p.who_is_master_response, 583 srcAddr); 584 break; 585 586 case TIME_PACKET_SYNC_REQUEST: 587 result = handleSyncRequest(&pkt.p.sync_request, srcAddr); 588 break; 589 590 case TIME_PACKET_SYNC_RESPONSE: 591 result = handleSyncResponse(&pkt.p.sync_response, srcAddr); 592 break; 593 594 case TIME_PACKET_MASTER_ANNOUNCEMENT: 595 result = handleMasterAnnouncement(&pkt.p.master_announcement, 596 srcAddr); 597 break; 598 599 default: { 600 ALOGD("%s:%d unknown packet type(%d)", 601 __PRETTY_FUNCTION__, __LINE__, pkt.packetType); 602 result = false; 603 } break; 604 } 605 606 return result; 607 } 608 609 bool CommonTimeServer::handleTimeout() { 610 // If we have no socket, then this must be a timeout to retry socket setup. 611 if (mSocket < 0) 612 return true; 613 614 switch (mState) { 615 case ICommonClock::STATE_INITIAL: 616 return handleTimeoutInitial(); 617 case ICommonClock::STATE_CLIENT: 618 return handleTimeoutClient(); 619 case ICommonClock::STATE_MASTER: 620 return handleTimeoutMaster(); 621 case ICommonClock::STATE_RONIN: 622 return handleTimeoutRonin(); 623 case ICommonClock::STATE_WAIT_FOR_ELECTION: 624 return handleTimeoutWaitForElection(); 625 } 626 627 return false; 628 } 629 630 bool CommonTimeServer::handleTimeoutInitial() { 631 if (++mInitial_WhoIsMasterRequestTimeouts == 632 kInitial_NumWhoIsMasterRetries) { 633 // none of our attempts to discover a master succeeded, so make 634 // this device the master 635 return becomeMaster("initial timeout"); 636 } else { 637 // retry the WhoIsMaster request 638 return sendWhoIsMasterRequest(); 639 } 640 } 641 642 bool CommonTimeServer::handleTimeoutClient() { 643 if (shouldPanicNotGettingGoodData()) 644 return becomeInitial("timeout panic, no good data"); 645 646 if (mClient_SyncRequestPending) { 647 mClient_SyncRequestPending = false; 648 649 if (++mClient_SyncRequestTimeouts < kClient_NumSyncRequestRetries) { 650 // a sync request has timed out, so retry 651 return sendSyncRequest(); 652 } else { 653 // The master has failed to respond to a sync request for too many 654 // times in a row. Assume the master is dead and start electing 655 // a new master. 656 return becomeRonin("master not responding"); 657 } 658 } else { 659 // initiate the next sync request 660 return sendSyncRequest(); 661 } 662 } 663 664 bool CommonTimeServer::handleTimeoutMaster() { 665 // send another announcement from the master 666 return sendMasterAnnouncement(); 667 } 668 669 bool CommonTimeServer::handleTimeoutRonin() { 670 if (++mRonin_WhoIsMasterRequestTimeouts == kRonin_NumWhoIsMasterRetries) { 671 // no other master is out there, so we won the election 672 return becomeMaster("no better masters detected"); 673 } else { 674 return sendWhoIsMasterRequest(); 675 } 676 } 677 678 bool CommonTimeServer::handleTimeoutWaitForElection() { 679 return becomeRonin("timeout waiting for election conclusion"); 680 } 681 682 bool CommonTimeServer::handleWhoIsMasterRequest( 683 const WhoIsMasterRequestPacket* request, 684 const sockaddr_storage& srcAddr) { 685 if (mState == ICommonClock::STATE_MASTER) { 686 // is this request related to this master's timeline? 687 if (request->timelineID != ICommonClock::kInvalidTimelineID && 688 request->timelineID != mTimelineID) 689 return true; 690 691 WhoIsMasterResponsePacket pkt; 692 pkt.initHeader(mTimelineID, mSyncGroupID); 693 pkt.deviceID = mDeviceID; 694 pkt.devicePriority = effectivePriority(); 695 696 uint8_t buf[256]; 697 ssize_t bufSz = pkt.serializePacket(buf, sizeof(buf)); 698 if (bufSz < 0) 699 return false; 700 701 ssize_t sendBytes = sendto( 702 mSocket, buf, bufSz, 0, 703 reinterpret_cast<const sockaddr *>(&srcAddr), 704 sizeof(srcAddr)); 705 if (sendBytes == -1) { 706 ALOGE("%s:%d sendto failed", __PRETTY_FUNCTION__, __LINE__); 707 return false; 708 } 709 } else if (mState == ICommonClock::STATE_RONIN) { 710 // if we hear a WhoIsMaster request from another device following 711 // the same timeline and that device wins arbitration, then we will stop 712 // trying to elect ourselves master and will instead wait for an 713 // announcement from the election winner 714 if (request->timelineID != mTimelineID) 715 return true; 716 717 if (arbitrateMaster(request->senderDeviceID, 718 request->senderDevicePriority, 719 mDeviceID, 720 effectivePriority())) 721 return becomeWaitForElection("would lose election"); 722 723 return true; 724 } else if (mState == ICommonClock::STATE_INITIAL) { 725 // If a group of devices booted simultaneously (e.g. after a power 726 // outage) and all of them are in the initial state and there is no 727 // master, then each device may time out and declare itself master at 728 // the same time. To avoid this, listen for 729 // WhoIsMaster(InvalidTimeline) requests from peers. If we would lose 730 // arbitration against that peer, reset our timeout count so that the 731 // peer has a chance to become master before we time out. 732 if (request->timelineID == ICommonClock::kInvalidTimelineID && 733 arbitrateMaster(request->senderDeviceID, 734 request->senderDevicePriority, 735 mDeviceID, 736 effectivePriority())) { 737 mInitial_WhoIsMasterRequestTimeouts = 0; 738 } 739 } 740 741 return true; 742 } 743 744 bool CommonTimeServer::handleWhoIsMasterResponse( 745 const WhoIsMasterResponsePacket* response, 746 const sockaddr_storage& srcAddr) { 747 if (mState == ICommonClock::STATE_INITIAL || mState == ICommonClock::STATE_RONIN) { 748 return becomeClient(srcAddr, 749 response->deviceID, 750 response->devicePriority, 751 response->timelineID, 752 "heard whois response"); 753 } else if (mState == ICommonClock::STATE_CLIENT) { 754 // if we get multiple responses because there are multiple devices 755 // who believe that they are master, then follow the master that 756 // wins arbitration 757 if (arbitrateMaster(response->deviceID, 758 response->devicePriority, 759 mClient_MasterDeviceID, 760 mClient_MasterDevicePriority)) { 761 return becomeClient(srcAddr, 762 response->deviceID, 763 response->devicePriority, 764 response->timelineID, 765 "heard whois response"); 766 } 767 } 768 769 return true; 770 } 771 772 bool CommonTimeServer::handleSyncRequest(const SyncRequestPacket* request, 773 const sockaddr_storage& srcAddr) { 774 SyncResponsePacket pkt; 775 pkt.initHeader(mTimelineID, mSyncGroupID); 776 777 if ((mState == ICommonClock::STATE_MASTER) && 778 (mTimelineID == request->timelineID)) { 779 int64_t rxLocalTime = mLastPacketRxLocalTime; 780 int64_t rxCommonTime; 781 782 // If we are master on an actual network and have actual clients, then 783 // we are no longer low priority. 784 setForceLowPriority(false); 785 786 if (OK != mCommonClock.localToCommon(rxLocalTime, &rxCommonTime)) { 787 return false; 788 } 789 790 int64_t txLocalTime = mLocalClock.getLocalTime();; 791 int64_t txCommonTime; 792 if (OK != mCommonClock.localToCommon(txLocalTime, &txCommonTime)) { 793 return false; 794 } 795 796 pkt.nak = 0; 797 pkt.clientTxLocalTime = request->clientTxLocalTime; 798 pkt.masterRxCommonTime = rxCommonTime; 799 pkt.masterTxCommonTime = txCommonTime; 800 } else { 801 pkt.nak = 1; 802 pkt.clientTxLocalTime = 0; 803 pkt.masterRxCommonTime = 0; 804 pkt.masterTxCommonTime = 0; 805 } 806 807 uint8_t buf[256]; 808 ssize_t bufSz = pkt.serializePacket(buf, sizeof(buf)); 809 if (bufSz < 0) 810 return false; 811 812 ssize_t sendBytes = sendto( 813 mSocket, &buf, bufSz, 0, 814 reinterpret_cast<const sockaddr *>(&srcAddr), 815 sizeof(srcAddr)); 816 if (sendBytes == -1) { 817 ALOGE("%s:%d sendto failed", __PRETTY_FUNCTION__, __LINE__); 818 return false; 819 } 820 821 return true; 822 } 823 824 bool CommonTimeServer::handleSyncResponse( 825 const SyncResponsePacket* response, 826 const sockaddr_storage& srcAddr) { 827 if (mState != ICommonClock::STATE_CLIENT) 828 return true; 829 830 assert(mMasterEPValid); 831 if (!sockaddrMatch(srcAddr, mMasterEP, true)) { 832 char srcEP[64], expectedEP[64]; 833 sockaddrToString(srcAddr, true, srcEP, sizeof(srcEP)); 834 sockaddrToString(mMasterEP, true, expectedEP, sizeof(expectedEP)); 835 ALOGI("Dropping sync response from unexpected address." 836 " Expected %s Got %s", expectedEP, srcEP); 837 return true; 838 } 839 840 if (response->nak) { 841 // if our master is no longer accepting requests, then we need to find 842 // a new master 843 return becomeRonin("master NAK'ed"); 844 } 845 846 mClient_SyncRequestPending = 0; 847 mClient_SyncRequestTimeouts = 0; 848 mClient_PacketRTTLog.logRX(response->clientTxLocalTime, 849 mLastPacketRxLocalTime); 850 851 bool result; 852 if (!(mClient_SyncRespsRXedFromCurMaster++)) { 853 // the first request/response exchange between a client and a master 854 // may take unusually long due to ARP, so discard it. 855 result = true; 856 } else { 857 int64_t clientTxLocalTime = response->clientTxLocalTime; 858 int64_t clientRxLocalTime = mLastPacketRxLocalTime; 859 int64_t masterTxCommonTime = response->masterTxCommonTime; 860 int64_t masterRxCommonTime = response->masterRxCommonTime; 861 862 int64_t rtt = (clientRxLocalTime - clientTxLocalTime); 863 int64_t avgLocal = (clientTxLocalTime + clientRxLocalTime) >> 1; 864 int64_t avgCommon = (masterTxCommonTime + masterRxCommonTime) >> 1; 865 866 // if the RTT of the packet is significantly larger than the panic 867 // threshold, we should simply discard it. Its better to do nothing 868 // than to take cues from a packet like that. 869 int rttCommon = mCommonClock.localDurationToCommonDuration(rtt); 870 if (rttCommon > (static_cast<int64_t>(mPanicThresholdUsec) * 871 kRTTDiscardPanicThreshMultiplier)) { 872 ALOGV("Dropping sync response with RTT of %lld uSec", rttCommon); 873 mClient_ExpiredSyncRespsRXedFromCurMaster++; 874 if (shouldPanicNotGettingGoodData()) 875 return becomeInitial("RX panic, no good data"); 876 } else { 877 result = mClockRecovery.pushDisciplineEvent(avgLocal, avgCommon, rttCommon); 878 mClient_LastGoodSyncRX = clientRxLocalTime; 879 880 if (result) { 881 // indicate to listeners that we've synced to the common timeline 882 notifyClockSync(); 883 } else { 884 ALOGE("Panic! Observed clock sync error is too high to tolerate," 885 " resetting state machine and starting over."); 886 notifyClockSyncLoss(); 887 return becomeInitial("panic"); 888 } 889 } 890 } 891 892 mCurTimeout.setTimeout(mSyncRequestIntervalMs); 893 return result; 894 } 895 896 bool CommonTimeServer::handleMasterAnnouncement( 897 const MasterAnnouncementPacket* packet, 898 const sockaddr_storage& srcAddr) { 899 uint64_t newDeviceID = packet->deviceID; 900 uint8_t newDevicePrio = packet->devicePriority; 901 uint64_t newTimelineID = packet->timelineID; 902 903 if (mState == ICommonClock::STATE_INITIAL || 904 mState == ICommonClock::STATE_RONIN || 905 mState == ICommonClock::STATE_WAIT_FOR_ELECTION) { 906 // if we aren't currently following a master, then start following 907 // this new master 908 return becomeClient(srcAddr, 909 newDeviceID, 910 newDevicePrio, 911 newTimelineID, 912 "heard master announcement"); 913 } else if (mState == ICommonClock::STATE_CLIENT) { 914 // if the new master wins arbitration against our current master, 915 // then become a client of the new master 916 if (arbitrateMaster(newDeviceID, 917 newDevicePrio, 918 mClient_MasterDeviceID, 919 mClient_MasterDevicePriority)) 920 return becomeClient(srcAddr, 921 newDeviceID, 922 newDevicePrio, 923 newTimelineID, 924 "heard master announcement"); 925 } else if (mState == ICommonClock::STATE_MASTER) { 926 // two masters are competing - if the new one wins arbitration, then 927 // cease acting as master 928 if (arbitrateMaster(newDeviceID, newDevicePrio, 929 mDeviceID, effectivePriority())) 930 return becomeClient(srcAddr, newDeviceID, 931 newDevicePrio, newTimelineID, 932 "heard master announcement"); 933 } 934 935 return true; 936 } 937 938 bool CommonTimeServer::sendWhoIsMasterRequest() { 939 assert(mState == ICommonClock::STATE_INITIAL || mState == ICommonClock::STATE_RONIN); 940 941 // If we have no socket, then we must be in the unconfigured initial state. 942 // Don't report any errors, just don't try to send the initial who-is-master 943 // query. Eventually, our network will either become configured, or we will 944 // be forced into network-less master mode by higher level code. 945 if (mSocket < 0) { 946 assert(mState == ICommonClock::STATE_INITIAL); 947 return true; 948 } 949 950 bool ret = false; 951 WhoIsMasterRequestPacket pkt; 952 pkt.initHeader(mSyncGroupID); 953 pkt.senderDeviceID = mDeviceID; 954 pkt.senderDevicePriority = effectivePriority(); 955 956 uint8_t buf[256]; 957 ssize_t bufSz = pkt.serializePacket(buf, sizeof(buf)); 958 if (bufSz >= 0) { 959 ssize_t sendBytes = sendto( 960 mSocket, buf, bufSz, 0, 961 reinterpret_cast<const sockaddr *>(&mMasterElectionEP), 962 sizeof(mMasterElectionEP)); 963 if (sendBytes < 0) 964 ALOGE("WhoIsMaster sendto failed (errno %d)", errno); 965 ret = true; 966 } 967 968 if (mState == ICommonClock::STATE_INITIAL) { 969 mCurTimeout.setTimeout(kInitial_WhoIsMasterTimeoutMs); 970 } else { 971 mCurTimeout.setTimeout(kRonin_WhoIsMasterTimeoutMs); 972 } 973 974 return ret; 975 } 976 977 bool CommonTimeServer::sendSyncRequest() { 978 // If we are sending sync requests, then we must be in the client state and 979 // we must have a socket (when we have no network, we are only supposed to 980 // be in INITIAL or MASTER) 981 assert(mState == ICommonClock::STATE_CLIENT); 982 assert(mSocket >= 0); 983 984 bool ret = false; 985 SyncRequestPacket pkt; 986 pkt.initHeader(mTimelineID, mSyncGroupID); 987 pkt.clientTxLocalTime = mLocalClock.getLocalTime(); 988 989 if (!mClient_FirstSyncTX) 990 mClient_FirstSyncTX = pkt.clientTxLocalTime; 991 992 mClient_PacketRTTLog.logTX(pkt.clientTxLocalTime); 993 994 uint8_t buf[256]; 995 ssize_t bufSz = pkt.serializePacket(buf, sizeof(buf)); 996 if (bufSz >= 0) { 997 ssize_t sendBytes = sendto( 998 mSocket, buf, bufSz, 0, 999 reinterpret_cast<const sockaddr *>(&mMasterEP), 1000 sizeof(mMasterEP)); 1001 if (sendBytes < 0) 1002 ALOGE("SyncRequest sendto failed (errno %d)", errno); 1003 ret = true; 1004 } 1005 1006 mClient_SyncsSentToCurMaster++; 1007 mCurTimeout.setTimeout(mSyncRequestIntervalMs); 1008 mClient_SyncRequestPending = true; 1009 1010 return ret; 1011 } 1012 1013 bool CommonTimeServer::sendMasterAnnouncement() { 1014 bool ret = false; 1015 assert(mState == ICommonClock::STATE_MASTER); 1016 1017 // If we are being asked to send a master announcement, but we have no 1018 // socket, we must be in network-less master mode. Don't bother to send the 1019 // announcement, and don't bother to schedule a timeout. When the network 1020 // comes up, the work thread will get poked and start the process of 1021 // figuring out who the current master should be. 1022 if (mSocket < 0) { 1023 mCurTimeout.setTimeout(kInfiniteTimeout); 1024 return true; 1025 } 1026 1027 MasterAnnouncementPacket pkt; 1028 pkt.initHeader(mTimelineID, mSyncGroupID); 1029 pkt.deviceID = mDeviceID; 1030 pkt.devicePriority = effectivePriority(); 1031 1032 uint8_t buf[256]; 1033 ssize_t bufSz = pkt.serializePacket(buf, sizeof(buf)); 1034 if (bufSz >= 0) { 1035 ssize_t sendBytes = sendto( 1036 mSocket, buf, bufSz, 0, 1037 reinterpret_cast<const sockaddr *>(&mMasterElectionEP), 1038 sizeof(mMasterElectionEP)); 1039 if (sendBytes < 0) 1040 ALOGE("MasterAnnouncement sendto failed (errno %d)", errno); 1041 ret = true; 1042 } 1043 1044 mCurTimeout.setTimeout(mMasterAnnounceIntervalMs); 1045 return ret; 1046 } 1047 1048 bool CommonTimeServer::becomeClient(const sockaddr_storage& masterEP, 1049 uint64_t masterDeviceID, 1050 uint8_t masterDevicePriority, 1051 uint64_t timelineID, 1052 const char* cause) { 1053 char newEPStr[64], oldEPStr[64]; 1054 sockaddrToString(masterEP, true, newEPStr, sizeof(newEPStr)); 1055 sockaddrToString(mMasterEP, mMasterEPValid, oldEPStr, sizeof(oldEPStr)); 1056 1057 ALOGI("%s --> CLIENT (%s) :%s" 1058 " OldMaster: %02x-%014llx::%016llx::%s" 1059 " NewMaster: %02x-%014llx::%016llx::%s", 1060 stateToString(mState), cause, 1061 (mTimelineID != timelineID) ? " (new timeline)" : "", 1062 mClient_MasterDevicePriority, mClient_MasterDeviceID, 1063 mTimelineID, oldEPStr, 1064 masterDevicePriority, masterDeviceID, 1065 timelineID, newEPStr); 1066 1067 if (mTimelineID != timelineID) { 1068 // start following a new timeline 1069 mTimelineID = timelineID; 1070 mClockRecovery.reset(true, true); 1071 notifyClockSyncLoss(); 1072 } else { 1073 // start following a new master on the existing timeline 1074 mClockRecovery.reset(false, true); 1075 } 1076 1077 mMasterEP = masterEP; 1078 mMasterEPValid = true; 1079 1080 // If we are on a real network as a client of a real master, then we should 1081 // no longer force low priority. If our master disappears, we should have 1082 // the high priority bit set during the election to replace the master 1083 // because this group was a real group and not a singleton created in 1084 // networkless mode. 1085 setForceLowPriority(false); 1086 1087 mClient_MasterDeviceID = masterDeviceID; 1088 mClient_MasterDevicePriority = masterDevicePriority; 1089 resetSyncStats(); 1090 1091 setState(ICommonClock::STATE_CLIENT); 1092 1093 // add some jitter to when the various clients send their requests 1094 // in order to reduce the likelihood that a group of clients overload 1095 // the master after receiving a master announcement 1096 usleep((lrand48() % 100) * 1000); 1097 1098 return sendSyncRequest(); 1099 } 1100 1101 bool CommonTimeServer::becomeMaster(const char* cause) { 1102 uint64_t oldTimelineID = mTimelineID; 1103 if (mTimelineID == ICommonClock::kInvalidTimelineID) { 1104 // this device has not been following any existing timeline, 1105 // so it will create a new timeline and declare itself master 1106 assert(!mCommonClock.isValid()); 1107 1108 // set the common time basis 1109 mCommonClock.setBasis(mLocalClock.getLocalTime(), 0); 1110 1111 // assign an arbitrary timeline iD 1112 assignTimelineID(); 1113 1114 // notify listeners that we've created a common timeline 1115 notifyClockSync(); 1116 } 1117 1118 ALOGI("%s --> MASTER (%s) : %s timeline %016llx", 1119 stateToString(mState), cause, 1120 (oldTimelineID == mTimelineID) ? "taking ownership of" 1121 : "creating new", 1122 mTimelineID); 1123 1124 memset(&mMasterEP, 0, sizeof(mMasterEP)); 1125 mMasterEPValid = false; 1126 mClient_MasterDevicePriority = effectivePriority(); 1127 mClient_MasterDeviceID = mDeviceID; 1128 mClockRecovery.reset(false, true); 1129 resetSyncStats(); 1130 1131 setState(ICommonClock::STATE_MASTER); 1132 return sendMasterAnnouncement(); 1133 } 1134 1135 bool CommonTimeServer::becomeRonin(const char* cause) { 1136 // If we were the client of a given timeline, but had never received even a 1137 // single time sync packet, then we transition back to Initial instead of 1138 // Ronin. If we transition to Ronin and end up becoming the new Master, we 1139 // will be unable to service requests for other clients because we never 1140 // actually knew what time it was. By going to initial, we ensure that 1141 // other clients who know what time it is, but would lose master arbitration 1142 // in the Ronin case, will step up and become the proper new master of the 1143 // old timeline. 1144 1145 char oldEPStr[64]; 1146 sockaddrToString(mMasterEP, mMasterEPValid, oldEPStr, sizeof(oldEPStr)); 1147 memset(&mMasterEP, 0, sizeof(mMasterEP)); 1148 mMasterEPValid = false; 1149 1150 if (mCommonClock.isValid()) { 1151 ALOGI("%s --> RONIN (%s) : lost track of previously valid timeline " 1152 "%02x-%014llx::%016llx::%s (%d TXed %d RXed %d RXExpired)", 1153 stateToString(mState), cause, 1154 mClient_MasterDevicePriority, mClient_MasterDeviceID, 1155 mTimelineID, oldEPStr, 1156 mClient_SyncsSentToCurMaster, 1157 mClient_SyncRespsRXedFromCurMaster, 1158 mClient_ExpiredSyncRespsRXedFromCurMaster); 1159 1160 mRonin_WhoIsMasterRequestTimeouts = 0; 1161 setState(ICommonClock::STATE_RONIN); 1162 return sendWhoIsMasterRequest(); 1163 } else { 1164 ALOGI("%s --> INITIAL (%s) : never synced timeline " 1165 "%02x-%014llx::%016llx::%s (%d TXed %d RXed %d RXExpired)", 1166 stateToString(mState), cause, 1167 mClient_MasterDevicePriority, mClient_MasterDeviceID, 1168 mTimelineID, oldEPStr, 1169 mClient_SyncsSentToCurMaster, 1170 mClient_SyncRespsRXedFromCurMaster, 1171 mClient_ExpiredSyncRespsRXedFromCurMaster); 1172 1173 return becomeInitial("ronin, no timeline"); 1174 } 1175 } 1176 1177 bool CommonTimeServer::becomeWaitForElection(const char* cause) { 1178 ALOGI("%s --> WAIT_FOR_ELECTION (%s) : dropping out of election," 1179 " waiting %d mSec for completion.", 1180 stateToString(mState), cause, kWaitForElection_TimeoutMs); 1181 1182 setState(ICommonClock::STATE_WAIT_FOR_ELECTION); 1183 mCurTimeout.setTimeout(kWaitForElection_TimeoutMs); 1184 return true; 1185 } 1186 1187 bool CommonTimeServer::becomeInitial(const char* cause) { 1188 ALOGI("Entering INITIAL (%s), total reset.", cause); 1189 1190 setState(ICommonClock::STATE_INITIAL); 1191 1192 // reset clock recovery 1193 mClockRecovery.reset(true, true); 1194 1195 // reset internal state bookkeeping. 1196 mCurTimeout.setTimeout(kInfiniteTimeout); 1197 memset(&mMasterEP, 0, sizeof(mMasterEP)); 1198 mMasterEPValid = false; 1199 mLastPacketRxLocalTime = 0; 1200 mTimelineID = ICommonClock::kInvalidTimelineID; 1201 mClockSynced = false; 1202 mInitial_WhoIsMasterRequestTimeouts = 0; 1203 mClient_MasterDeviceID = 0; 1204 mClient_MasterDevicePriority = 0; 1205 mRonin_WhoIsMasterRequestTimeouts = 0; 1206 resetSyncStats(); 1207 1208 // send the first request to discover the master 1209 return sendWhoIsMasterRequest(); 1210 } 1211 1212 void CommonTimeServer::notifyClockSync() { 1213 if (!mClockSynced) { 1214 mClockSynced = true; 1215 mICommonClock->notifyOnTimelineChanged(mTimelineID); 1216 } 1217 } 1218 1219 void CommonTimeServer::notifyClockSyncLoss() { 1220 if (mClockSynced) { 1221 mClockSynced = false; 1222 mICommonClock->notifyOnTimelineChanged( 1223 ICommonClock::kInvalidTimelineID); 1224 } 1225 } 1226 1227 void CommonTimeServer::setState(ICommonClock::State s) { 1228 mState = s; 1229 } 1230 1231 const char* CommonTimeServer::stateToString(ICommonClock::State s) { 1232 switch(s) { 1233 case ICommonClock::STATE_INITIAL: 1234 return "INITIAL"; 1235 case ICommonClock::STATE_CLIENT: 1236 return "CLIENT"; 1237 case ICommonClock::STATE_MASTER: 1238 return "MASTER"; 1239 case ICommonClock::STATE_RONIN: 1240 return "RONIN"; 1241 case ICommonClock::STATE_WAIT_FOR_ELECTION: 1242 return "WAIT_FOR_ELECTION"; 1243 default: 1244 return "unknown"; 1245 } 1246 } 1247 1248 void CommonTimeServer::sockaddrToString(const sockaddr_storage& addr, 1249 bool addrValid, 1250 char* buf, size_t bufLen) { 1251 if (!bufLen || !buf) 1252 return; 1253 1254 if (addrValid) { 1255 switch (addr.ss_family) { 1256 case AF_INET: { 1257 const struct sockaddr_in* sa = 1258 reinterpret_cast<const struct sockaddr_in*>(&addr); 1259 unsigned long a = ntohl(sa->sin_addr.s_addr); 1260 uint16_t p = ntohs(sa->sin_port); 1261 snprintf(buf, bufLen, "%lu.%lu.%lu.%lu:%hu", 1262 ((a >> 24) & 0xFF), ((a >> 16) & 0xFF), 1263 ((a >> 8) & 0xFF), (a & 0xFF), p); 1264 } break; 1265 1266 case AF_INET6: { 1267 const struct sockaddr_in6* sa = 1268 reinterpret_cast<const struct sockaddr_in6*>(&addr); 1269 const uint8_t* a = sa->sin6_addr.s6_addr; 1270 uint16_t p = ntohs(sa->sin6_port); 1271 snprintf(buf, bufLen, 1272 "%02X%02X:%02X%02X:%02X%02X:%02X%02X:" 1273 "%02X%02X:%02X%02X:%02X%02X:%02X%02X port %hd", 1274 a[0], a[1], a[ 2], a[ 3], a[ 4], a[ 5], a[ 6], a[ 7], 1275 a[8], a[9], a[10], a[11], a[12], a[13], a[14], a[15], 1276 p); 1277 } break; 1278 1279 default: 1280 snprintf(buf, bufLen, 1281 "<unknown sockaddr family %d>", addr.ss_family); 1282 break; 1283 } 1284 } else { 1285 snprintf(buf, bufLen, "<none>"); 1286 } 1287 1288 buf[bufLen - 1] = 0; 1289 } 1290 1291 bool CommonTimeServer::sockaddrMatch(const sockaddr_storage& a1, 1292 const sockaddr_storage& a2, 1293 bool matchAddressOnly) { 1294 if (a1.ss_family != a2.ss_family) 1295 return false; 1296 1297 switch (a1.ss_family) { 1298 case AF_INET: { 1299 const struct sockaddr_in* sa1 = 1300 reinterpret_cast<const struct sockaddr_in*>(&a1); 1301 const struct sockaddr_in* sa2 = 1302 reinterpret_cast<const struct sockaddr_in*>(&a2); 1303 1304 if (sa1->sin_addr.s_addr != sa2->sin_addr.s_addr) 1305 return false; 1306 1307 return (matchAddressOnly || (sa1->sin_port == sa2->sin_port)); 1308 } break; 1309 1310 case AF_INET6: { 1311 const struct sockaddr_in6* sa1 = 1312 reinterpret_cast<const struct sockaddr_in6*>(&a1); 1313 const struct sockaddr_in6* sa2 = 1314 reinterpret_cast<const struct sockaddr_in6*>(&a2); 1315 1316 if (memcmp(&sa1->sin6_addr, &sa2->sin6_addr, sizeof(sa2->sin6_addr))) 1317 return false; 1318 1319 return (matchAddressOnly || (sa1->sin6_port == sa2->sin6_port)); 1320 } break; 1321 1322 // Huh? We don't deal in non-IPv[46] addresses. Not sure how we got 1323 // here, but we don't know how to comapre these addresses and simply 1324 // default to a no-match decision. 1325 default: return false; 1326 } 1327 } 1328 1329 void CommonTimeServer::TimeoutHelper::setTimeout(int msec) { 1330 mTimeoutValid = (msec >= 0); 1331 if (mTimeoutValid) 1332 mEndTime = systemTime() + 1333 (static_cast<nsecs_t>(msec) * 1000000); 1334 } 1335 1336 int CommonTimeServer::TimeoutHelper::msecTillTimeout() { 1337 if (!mTimeoutValid) 1338 return kInfiniteTimeout; 1339 1340 nsecs_t now = systemTime(); 1341 if (now >= mEndTime) 1342 return 0; 1343 1344 uint64_t deltaMsec = (((mEndTime - now) + 999999) / 1000000); 1345 1346 if (deltaMsec > static_cast<uint64_t>(MAX_INT)) 1347 return MAX_INT; 1348 1349 return static_cast<int>(deltaMsec); 1350 } 1351 1352 bool CommonTimeServer::shouldPanicNotGettingGoodData() { 1353 if (mClient_FirstSyncTX) { 1354 int64_t now = mLocalClock.getLocalTime(); 1355 int64_t delta = now - (mClient_LastGoodSyncRX 1356 ? mClient_LastGoodSyncRX 1357 : mClient_FirstSyncTX); 1358 int64_t deltaUsec = mCommonClock.localDurationToCommonDuration(delta); 1359 1360 if (deltaUsec >= kNoGoodDataPanicThresholdUsec) 1361 return true; 1362 } 1363 1364 return false; 1365 } 1366 1367 void CommonTimeServer::PacketRTTLog::logTX(int64_t txTime) { 1368 txTimes[wrPtr] = txTime; 1369 rxTimes[wrPtr] = 0; 1370 wrPtr = (wrPtr + 1) % RTT_LOG_SIZE; 1371 if (!wrPtr) 1372 logFull = true; 1373 } 1374 1375 void CommonTimeServer::PacketRTTLog::logRX(int64_t txTime, int64_t rxTime) { 1376 if (!logFull && !wrPtr) 1377 return; 1378 1379 uint32_t i = logFull ? wrPtr : 0; 1380 do { 1381 if (txTimes[i] == txTime) { 1382 rxTimes[i] = rxTime; 1383 break; 1384 } 1385 i = (i + 1) % RTT_LOG_SIZE; 1386 } while (i != wrPtr); 1387 } 1388 1389 } // namespace android 1390
