Jorge E. Moreira | a18ff1a | 2019-12-17 18:20:56 -0800 | [diff] [blame] | 1 | #include <webrtc/RTPSocketHandler.h> |
| 2 | |
| 3 | #include <webrtc/MyWebSocketHandler.h> |
| 4 | #include <webrtc/STUNMessage.h> |
Jorge E. Moreira | 2a6ab08 | 2019-12-11 18:41:58 -0800 | [diff] [blame] | 5 | #include <Utils.h> |
Jorge E. Moreira | a18ff1a | 2019-12-17 18:20:56 -0800 | [diff] [blame] | 6 | |
| 7 | #include <https/PlainSocket.h> |
| 8 | #include <https/SafeCallbackable.h> |
| 9 | #include <https/Support.h> |
Jorge E. Moreira | 2a6ab08 | 2019-12-11 18:41:58 -0800 | [diff] [blame] | 10 | #include <android-base/logging.h> |
Jorge E. Moreira | a18ff1a | 2019-12-17 18:20:56 -0800 | [diff] [blame] | 11 | |
| 12 | #include <netdb.h> |
| 13 | #include <netinet/in.h> |
| 14 | |
| 15 | #include <cstring> |
| 16 | #include <iostream> |
| 17 | #include <set> |
| 18 | |
Jorge E. Moreira | a18ff1a | 2019-12-17 18:20:56 -0800 | [diff] [blame] | 19 | #include <gflags/gflags.h> |
| 20 | |
| 21 | DECLARE_string(public_ip); |
Jorge E. Moreira | a18ff1a | 2019-12-17 18:20:56 -0800 | [diff] [blame] | 22 | |
| 23 | static socklen_t getSockAddrLen(const sockaddr_storage &addr) { |
| 24 | switch (addr.ss_family) { |
| 25 | case AF_INET: |
| 26 | return sizeof(sockaddr_in); |
| 27 | case AF_INET6: |
| 28 | return sizeof(sockaddr_in6); |
| 29 | default: |
| 30 | CHECK(!"Should not be here."); |
| 31 | return 0; |
| 32 | } |
| 33 | } |
| 34 | |
| 35 | RTPSocketHandler::RTPSocketHandler( |
| 36 | std::shared_ptr<RunLoop> runLoop, |
| 37 | std::shared_ptr<ServerState> serverState, |
| 38 | int domain, |
| 39 | uint16_t port, |
| 40 | uint32_t trackMask, |
| 41 | std::shared_ptr<RTPSession> session) |
| 42 | : mRunLoop(runLoop), |
| 43 | mServerState(serverState), |
| 44 | mLocalPort(port), |
| 45 | mTrackMask(trackMask), |
| 46 | mSession(session), |
| 47 | mSendPending(false), |
| 48 | mDTLSConnected(false) { |
| 49 | int sock = socket(domain, SOCK_DGRAM, 0); |
| 50 | |
| 51 | makeFdNonblocking(sock); |
| 52 | mSocket = std::make_shared<PlainSocket>(mRunLoop, sock); |
| 53 | |
| 54 | sockaddr_storage addr; |
| 55 | |
| 56 | if (domain == PF_INET) { |
| 57 | sockaddr_in addrV4; |
| 58 | memset(addrV4.sin_zero, 0, sizeof(addrV4.sin_zero)); |
| 59 | addrV4.sin_family = AF_INET; |
| 60 | addrV4.sin_port = htons(port); |
| 61 | addrV4.sin_addr.s_addr = INADDR_ANY; |
| 62 | memcpy(&addr, &addrV4, sizeof(addrV4)); |
| 63 | } else { |
| 64 | CHECK_EQ(domain, PF_INET6); |
| 65 | |
| 66 | sockaddr_in6 addrV6; |
| 67 | addrV6.sin6_family = AF_INET6; |
| 68 | addrV6.sin6_port = htons(port); |
| 69 | addrV6.sin6_addr = in6addr_any; |
| 70 | addrV6.sin6_scope_id = 0; |
| 71 | memcpy(&addr, &addrV6, sizeof(addrV6)); |
| 72 | } |
| 73 | |
| 74 | int res = bind( |
| 75 | sock, |
| 76 | reinterpret_cast<const sockaddr *>(&addr), |
| 77 | getSockAddrLen(addr)); |
| 78 | |
| 79 | CHECK(!res); |
| 80 | |
| 81 | auto videoPacketizer = |
| 82 | (trackMask & TRACK_VIDEO) |
| 83 | ? mServerState->getVideoPacketizer() : nullptr; |
| 84 | |
| 85 | auto audioPacketizer = |
| 86 | (trackMask & TRACK_AUDIO) |
| 87 | ? mServerState->getAudioPacketizer() : nullptr; |
| 88 | |
| 89 | mRTPSender = std::make_shared<RTPSender>( |
| 90 | mRunLoop, |
| 91 | this, |
| 92 | videoPacketizer, |
| 93 | audioPacketizer); |
| 94 | |
| 95 | if (trackMask & TRACK_VIDEO) { |
| 96 | mRTPSender->addSource(0xdeadbeef); |
| 97 | mRTPSender->addSource(0xcafeb0b0); |
| 98 | |
| 99 | mRTPSender->addRetransInfo(0xdeadbeef, 96, 0xcafeb0b0, 97); |
| 100 | |
| 101 | videoPacketizer->addSender(mRTPSender); |
| 102 | } |
| 103 | |
| 104 | if (trackMask & TRACK_AUDIO) { |
| 105 | mRTPSender->addSource(0x8badf00d); |
| 106 | |
| 107 | audioPacketizer->addSender(mRTPSender); |
| 108 | } |
| 109 | } |
| 110 | |
Jorge E. Moreira | a18ff1a | 2019-12-17 18:20:56 -0800 | [diff] [blame] | 111 | uint16_t RTPSocketHandler::getLocalPort() const { |
| 112 | return mLocalPort; |
| 113 | } |
| 114 | |
| 115 | std::string RTPSocketHandler::getLocalUFrag() const { |
| 116 | return mSession->localUFrag(); |
| 117 | } |
| 118 | |
| 119 | std::string RTPSocketHandler::getLocalIPString() const { |
Jorge E. Moreira | a18ff1a | 2019-12-17 18:20:56 -0800 | [diff] [blame] | 120 | return FLAGS_public_ip; |
Jorge E. Moreira | a18ff1a | 2019-12-17 18:20:56 -0800 | [diff] [blame] | 121 | } |
| 122 | |
| 123 | void RTPSocketHandler::run() { |
| 124 | mSocket->postRecv(makeSafeCallback(this, &RTPSocketHandler::onReceive)); |
| 125 | } |
| 126 | |
| 127 | void RTPSocketHandler::onReceive() { |
| 128 | std::vector<uint8_t> buffer(kMaxUDPPayloadSize); |
| 129 | |
| 130 | uint8_t *data = buffer.data(); |
| 131 | |
| 132 | sockaddr_storage addr; |
| 133 | socklen_t addrLen = sizeof(addr); |
| 134 | |
| 135 | auto n = mSocket->recvfrom( |
| 136 | data, buffer.size(), reinterpret_cast<sockaddr *>(&addr), &addrLen); |
| 137 | |
Jorge E. Moreira | a18ff1a | 2019-12-17 18:20:56 -0800 | [diff] [blame] | 138 | STUNMessage msg(data, n); |
| 139 | if (!msg.isValid()) { |
| 140 | if (mDTLSConnected) { |
| 141 | int err = -EINVAL; |
| 142 | if (mRTPSender) { |
| 143 | err = onSRTPReceive(data, static_cast<size_t>(n)); |
| 144 | } |
| 145 | |
| 146 | if (err == -EINVAL) { |
| 147 | LOG(VERBOSE) << "Sending to DTLS instead:"; |
| 148 | // hexdump(data, n); |
| 149 | |
| 150 | onDTLSReceive(data, static_cast<size_t>(n)); |
| 151 | |
| 152 | if (mTrackMask & TRACK_DATA) { |
| 153 | ssize_t n; |
| 154 | |
| 155 | do { |
| 156 | uint8_t buf[kMaxUDPPayloadSize]; |
| 157 | n = mDTLS->readApplicationData(buf, sizeof(buf)); |
| 158 | |
| 159 | if (n > 0) { |
| 160 | auto err = mSCTPHandler->inject( |
| 161 | buf, static_cast<size_t>(n)); |
| 162 | |
| 163 | if (err) { |
| 164 | LOG(WARNING) |
| 165 | << "SCTPHandler::inject returned error " |
| 166 | << err; |
| 167 | } |
| 168 | } |
| 169 | } while (n > 0); |
| 170 | } |
| 171 | } |
| 172 | } else { |
| 173 | onDTLSReceive(data, static_cast<size_t>(n)); |
| 174 | } |
| 175 | |
| 176 | run(); |
| 177 | return; |
| 178 | } |
| 179 | |
| 180 | if (msg.type() == 0x0001 /* Binding Request */) { |
| 181 | STUNMessage response(0x0101 /* Binding Response */, msg.data() + 8); |
| 182 | |
| 183 | if (!matchesSession(msg)) { |
| 184 | LOG(WARNING) << "Unknown session or no USERNAME."; |
| 185 | run(); |
| 186 | return; |
| 187 | } |
| 188 | |
| 189 | const auto &answerPassword = mSession->localPassword(); |
| 190 | |
| 191 | // msg.dump(answerPassword); |
| 192 | |
| 193 | if (addr.ss_family == AF_INET) { |
| 194 | uint8_t attr[8]; |
| 195 | attr[0] = 0x00; |
| 196 | |
| 197 | sockaddr_in addrV4; |
| 198 | CHECK_EQ(addrLen, sizeof(addrV4)); |
| 199 | |
| 200 | memcpy(&addrV4, &addr, addrLen); |
| 201 | |
| 202 | attr[1] = 0x01; // IPv4 |
| 203 | |
| 204 | static constexpr uint32_t kMagicCookie = 0x2112a442; |
| 205 | |
| 206 | uint16_t portHost = ntohs(addrV4.sin_port); |
| 207 | portHost ^= (kMagicCookie >> 16); |
| 208 | |
| 209 | uint32_t ipHost = ntohl(addrV4.sin_addr.s_addr); |
| 210 | ipHost ^= kMagicCookie; |
| 211 | |
| 212 | attr[2] = portHost >> 8; |
| 213 | attr[3] = portHost & 0xff; |
| 214 | attr[4] = ipHost >> 24; |
| 215 | attr[5] = (ipHost >> 16) & 0xff; |
| 216 | attr[6] = (ipHost >> 8) & 0xff; |
| 217 | attr[7] = ipHost & 0xff; |
| 218 | |
| 219 | response.addAttribute( |
| 220 | 0x0020 /* XOR-MAPPED-ADDRESS */, attr, sizeof(attr)); |
| 221 | } else { |
| 222 | uint8_t attr[20]; |
| 223 | attr[0] = 0x00; |
| 224 | |
| 225 | CHECK_EQ(addr.ss_family, AF_INET6); |
| 226 | |
| 227 | sockaddr_in6 addrV6; |
| 228 | CHECK_EQ(addrLen, sizeof(addrV6)); |
| 229 | |
| 230 | memcpy(&addrV6, &addr, addrLen); |
| 231 | |
| 232 | attr[1] = 0x02; // IPv6 |
| 233 | |
| 234 | static constexpr uint32_t kMagicCookie = 0x2112a442; |
| 235 | |
| 236 | uint16_t portHost = ntohs(addrV6.sin6_port); |
| 237 | portHost ^= (kMagicCookie >> 16); |
| 238 | |
| 239 | attr[2] = portHost >> 8; |
| 240 | attr[3] = portHost & 0xff; |
| 241 | |
| 242 | uint8_t ipHost[16]; |
| 243 | |
| 244 | std::string out; |
| 245 | |
| 246 | for (size_t i = 0; i < 16; ++i) { |
| 247 | ipHost[i] = addrV6.sin6_addr.s6_addr[15 - i]; |
| 248 | |
| 249 | if (!out.empty()) { |
| 250 | out += ":"; |
| 251 | } |
Jorge E. Moreira | 2a6ab08 | 2019-12-11 18:41:58 -0800 | [diff] [blame] | 252 | out += StringPrintf("%02x", ipHost[i]); |
Jorge E. Moreira | a18ff1a | 2019-12-17 18:20:56 -0800 | [diff] [blame] | 253 | |
| 254 | ipHost[i] ^= response.data()[4 + i]; |
| 255 | } |
| 256 | |
| 257 | // LOG(INFO) << "IP6 = " << out; |
| 258 | |
| 259 | for (size_t i = 0; i < 16; ++i) { |
| 260 | attr[4 + i] = ipHost[15 - i]; |
| 261 | } |
| 262 | |
| 263 | response.addAttribute( |
| 264 | 0x0020 /* XOR-MAPPED-ADDRESS */, attr, sizeof(attr)); |
| 265 | } |
| 266 | |
| 267 | response.addMessageIntegrityAttribute(answerPassword); |
| 268 | response.addFingerprint(); |
| 269 | |
| 270 | // response.dump(answerPassword); |
| 271 | |
| 272 | auto res = |
| 273 | mSocket->sendto( |
| 274 | response.data(), |
| 275 | response.size(), |
| 276 | reinterpret_cast<const sockaddr *>(&addr), |
| 277 | addrLen); |
| 278 | |
| 279 | CHECK_GT(res, 0); |
| 280 | CHECK_EQ(static_cast<size_t>(res), response.size()); |
| 281 | |
| 282 | if (!mSession->isActive()) { |
| 283 | mSession->setRemoteAddress(addr); |
| 284 | |
| 285 | mSession->setIsActive(); |
| 286 | |
| 287 | mSession->schedulePing( |
| 288 | mRunLoop, |
| 289 | makeSafeCallback( |
| 290 | this, &RTPSocketHandler::pingRemote, mSession), |
| 291 | std::chrono::seconds(0)); |
| 292 | } |
| 293 | |
| 294 | } else { |
| 295 | // msg.dump(); |
| 296 | |
| 297 | if (msg.type() == 0x0101 && !mDTLS) { |
| 298 | mDTLS = std::make_shared<DTLS>( |
| 299 | shared_from_this(), |
| 300 | DTLS::Mode::ACCEPT, |
| 301 | mSession->localCertificate(), |
| 302 | mSession->localKey(), |
| 303 | mSession->remoteFingerprint(), |
| 304 | (mTrackMask != TRACK_DATA) /* useSRTP */); |
| 305 | |
| 306 | mDTLS->connect(mSession->remoteAddress()); |
| 307 | } |
| 308 | } |
| 309 | |
| 310 | run(); |
| 311 | } |
| 312 | |
| 313 | bool RTPSocketHandler::matchesSession(const STUNMessage &msg) const { |
| 314 | const void *attrData; |
| 315 | size_t attrSize; |
| 316 | if (!msg.findAttribute(0x0006 /* USERNAME */, &attrData, &attrSize)) { |
| 317 | return false; |
| 318 | } |
| 319 | |
| 320 | std::string uFragPair(static_cast<const char *>(attrData), attrSize); |
| 321 | auto colonPos = uFragPair.find(':'); |
| 322 | |
| 323 | if (colonPos == std::string::npos) { |
| 324 | return false; |
| 325 | } |
| 326 | |
| 327 | std::string localUFrag(uFragPair, 0, colonPos); |
| 328 | std::string remoteUFrag(uFragPair, colonPos + 1); |
| 329 | |
| 330 | if (mSession->localUFrag() != localUFrag |
| 331 | || mSession->remoteUFrag() != remoteUFrag) { |
| 332 | |
| 333 | LOG(WARNING) |
| 334 | << "Unable to find session localUFrag='" |
| 335 | << localUFrag |
| 336 | << "', remoteUFrag='" |
| 337 | << remoteUFrag |
| 338 | << "'"; |
| 339 | |
| 340 | return false; |
| 341 | } |
| 342 | |
| 343 | return true; |
| 344 | } |
| 345 | |
| 346 | void RTPSocketHandler::pingRemote(std::shared_ptr<RTPSession> session) { |
| 347 | std::vector<uint8_t> transactionID { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 }; |
| 348 | |
| 349 | STUNMessage msg( |
| 350 | 0x0001 /* Binding Request */, |
| 351 | transactionID.data()); |
| 352 | |
| 353 | std::string uFragPair = |
| 354 | session->remoteUFrag() + ":" + session->localUFrag(); |
| 355 | |
| 356 | msg.addAttribute( |
| 357 | 0x0006 /* USERNAME */, |
| 358 | uFragPair.c_str(), |
| 359 | uFragPair.size()); |
| 360 | |
| 361 | uint64_t tieBreaker = 0xdeadbeefcafeb0b0; // XXX |
| 362 | msg.addAttribute( |
| 363 | 0x802a /* ICE-CONTROLLING */, |
| 364 | &tieBreaker, |
| 365 | sizeof(tieBreaker)); |
| 366 | |
| 367 | uint32_t priority = 0xdeadbeef; |
| 368 | msg.addAttribute( |
| 369 | 0x0024 /* PRIORITY */, &priority, sizeof(priority)); |
| 370 | |
| 371 | // We're the controlling agent and including the "USE-CANDIDATE" attribute |
| 372 | // below nominates this candidate. |
| 373 | msg.addAttribute(0x0025 /* USE_CANDIDATE */); |
| 374 | |
| 375 | msg.addMessageIntegrityAttribute(session->remotePassword()); |
| 376 | msg.addFingerprint(); |
| 377 | |
| 378 | queueDatagram(session->remoteAddress(), msg.data(), msg.size()); |
| 379 | |
| 380 | session->schedulePing( |
| 381 | mRunLoop, |
| 382 | makeSafeCallback(this, &RTPSocketHandler::pingRemote, session), |
| 383 | std::chrono::seconds(1)); |
| 384 | } |
| 385 | |
| 386 | RTPSocketHandler::Datagram::Datagram( |
| 387 | const sockaddr_storage &addr, const void *data, size_t size) |
| 388 | : mData(size), |
| 389 | mAddr(addr) { |
| 390 | memcpy(mData.data(), data, size); |
| 391 | } |
| 392 | |
| 393 | const void *RTPSocketHandler::Datagram::data() const { |
| 394 | return mData.data(); |
| 395 | } |
| 396 | |
| 397 | size_t RTPSocketHandler::Datagram::size() const { |
| 398 | return mData.size(); |
| 399 | } |
| 400 | |
| 401 | const sockaddr_storage &RTPSocketHandler::Datagram::remoteAddress() const { |
| 402 | return mAddr; |
| 403 | } |
| 404 | |
| 405 | void RTPSocketHandler::queueDatagram( |
| 406 | const sockaddr_storage &addr, const void *data, size_t size) { |
| 407 | auto datagram = std::make_shared<Datagram>(addr, data, size); |
| 408 | |
| 409 | CHECK_LE(size, RTPSocketHandler::kMaxUDPPayloadSize); |
| 410 | |
| 411 | mRunLoop->post( |
| 412 | makeSafeCallback<RTPSocketHandler>( |
| 413 | this, |
| 414 | [datagram](RTPSocketHandler *me) { |
| 415 | me->mOutQueue.push_back(datagram); |
| 416 | |
| 417 | if (!me->mSendPending) { |
| 418 | me->scheduleDrainOutQueue(); |
| 419 | } |
| 420 | })); |
| 421 | } |
| 422 | |
| 423 | void RTPSocketHandler::scheduleDrainOutQueue() { |
| 424 | CHECK(!mSendPending); |
| 425 | |
| 426 | mSendPending = true; |
| 427 | mSocket->postSend( |
| 428 | makeSafeCallback( |
| 429 | this, &RTPSocketHandler::drainOutQueue)); |
| 430 | } |
| 431 | |
| 432 | void RTPSocketHandler::drainOutQueue() { |
| 433 | mSendPending = false; |
| 434 | |
| 435 | CHECK(!mOutQueue.empty()); |
| 436 | |
| 437 | do { |
| 438 | auto datagram = mOutQueue.front(); |
| 439 | |
| 440 | ssize_t n; |
| 441 | do { |
| 442 | const sockaddr_storage &remoteAddr = datagram->remoteAddress(); |
| 443 | |
| 444 | n = mSocket->sendto( |
| 445 | datagram->data(), |
| 446 | datagram->size(), |
| 447 | reinterpret_cast<const sockaddr *>(&remoteAddr), |
| 448 | getSockAddrLen(remoteAddr)); |
| 449 | } while (n < 0 && errno == EINTR); |
| 450 | |
| 451 | if (n < 0) { |
| 452 | if (errno == EAGAIN || errno == EWOULDBLOCK) { |
| 453 | break; |
| 454 | } |
| 455 | |
| 456 | CHECK(!"Should not be here"); |
| 457 | } |
| 458 | |
| 459 | mOutQueue.pop_front(); |
| 460 | |
| 461 | } while (!mOutQueue.empty()); |
| 462 | |
| 463 | if (!mOutQueue.empty()) { |
| 464 | scheduleDrainOutQueue(); |
| 465 | } |
| 466 | } |
| 467 | |
| 468 | void RTPSocketHandler::onDTLSReceive(const uint8_t *data, size_t size) { |
| 469 | if (mDTLS) { |
| 470 | mDTLS->inject(data, size); |
| 471 | } |
| 472 | } |
| 473 | |
| 474 | void RTPSocketHandler::notifyDTLSConnected() { |
| 475 | LOG(INFO) << "TDLS says that it's now connected."; |
| 476 | |
| 477 | mDTLSConnected = true; |
| 478 | |
| 479 | if (mTrackMask & TRACK_DATA) { |
| 480 | mSCTPHandler = std::make_shared<SCTPHandler>(mRunLoop, mDTLS); |
| 481 | mSCTPHandler->run(); |
| 482 | } |
| 483 | |
| 484 | mRTPSender->run(); |
| 485 | } |
| 486 | |
| 487 | int RTPSocketHandler::onSRTPReceive(uint8_t *data, size_t size) { |
Jorge E. Moreira | a18ff1a | 2019-12-17 18:20:56 -0800 | [diff] [blame] | 488 | if (size < 2) { |
| 489 | return -EINVAL; |
| 490 | } |
| 491 | |
| 492 | auto version = data[0] >> 6; |
| 493 | if (version != 2) { |
| 494 | return -EINVAL; |
| 495 | } |
| 496 | |
| 497 | auto outSize = mDTLS->unprotect(data, size, false /* isRTP */); |
| 498 | |
Jorge E. Moreira | a18ff1a | 2019-12-17 18:20:56 -0800 | [diff] [blame] | 499 | auto err = mRTPSender->injectRTCP(data, outSize); |
| 500 | if (err) { |
| 501 | LOG(WARNING) << "RTPSender::injectRTCP returned " << err; |
| 502 | } |
| 503 | |
| 504 | return err; |
| 505 | } |
| 506 | |
| 507 | void RTPSocketHandler::queueRTCPDatagram(const void *data, size_t size) { |
| 508 | if (!mDTLSConnected) { |
| 509 | return; |
| 510 | } |
| 511 | |
| 512 | std::vector<uint8_t> copy(size + SRTP_MAX_TRAILER_LEN); |
| 513 | memcpy(copy.data(), data, size); |
| 514 | |
| 515 | auto outSize = mDTLS->protect(copy.data(), size, false /* isRTP */); |
| 516 | CHECK_LE(outSize, copy.size()); |
| 517 | |
| 518 | queueDatagram(mSession->remoteAddress(), copy.data(), outSize); |
| 519 | } |
| 520 | |
| 521 | void RTPSocketHandler::queueRTPDatagram(const void *data, size_t size) { |
| 522 | if (!mDTLSConnected) { |
| 523 | return; |
| 524 | } |
| 525 | |
| 526 | std::vector<uint8_t> copy(size + SRTP_MAX_TRAILER_LEN); |
| 527 | memcpy(copy.data(), data, size); |
| 528 | |
| 529 | auto outSize = mDTLS->protect(copy.data(), size, true /* isRTP */); |
| 530 | CHECK_LE(outSize, copy.size()); |
| 531 | |
| 532 | queueDatagram(mSession->remoteAddress(), copy.data(), outSize); |
| 533 | } |