src/net/net.cpp

   1 #include "Connection.hpp"
   2 #include "ConnectionHandler.hpp"
   3 #include "io.hpp"
   4 #include "Packet.hpp"
   5
   6 #include "../app/init.hpp"
   7 #include "../model/Model.hpp"
   8 #include "../world/Entity.hpp"
   9 #include "../world/EntityState.hpp"
  10
  11 #include <cstring>
  12
  13 using namespace std;
  14
  15
  16 namespace blank {
  17
  18 constexpr size_t Packet::Ping::MAX_LEN;
  19 constexpr size_t Packet::Login::MAX_LEN;
  20 constexpr size_t Packet::Join::MAX_LEN;
  21 constexpr size_t Packet::Part::MAX_LEN;
  22 constexpr size_t Packet::PlayerUpdate::MAX_LEN;
  23 constexpr size_t Packet::SpawnEntity::MAX_LEN;
  24 constexpr size_t Packet::DespawnEntity::MAX_LEN;
  25 constexpr size_t Packet::EntityUpdate::MAX_LEN;
  26 constexpr size_t Packet::PlayerCorrection::MAX_LEN;
  27 constexpr size_t Packet::ChunkBegin::MAX_LEN;
  28 constexpr size_t Packet::ChunkData::MAX_LEN;
  29 constexpr size_t Packet::BlockUpdate::MAX_LEN;
  30 constexpr size_t Packet::Message::MAX_LEN;
  31 constexpr size_t Packet::Message::MAX_MESSAGE_LEN;
  32
  33 Connection::Connection(const IPaddress &addr)
  34 : handler(nullptr)
  35 , addr(addr)
  36 , send_timer(500)
  37 , recv_timer(10000)
  38 , ctrl_out{ 0, 0xFFFF, 0xFFFFFFFF }
  39 , ctrl_in{ 0, 0xFFFF, 0xFFFFFFFF }
  40 , closed(false) {
  41         send_timer.Start();
  42         recv_timer.Start();
  43 }
  44
  45 bool Connection::Matches(const IPaddress &remote) const noexcept {
  46         return memcmp(&addr, &remote, sizeof(IPaddress)) == 0;
  47 }
  48
  49 void Connection::FlagSend() noexcept {
  50         send_timer.Reset();
  51 }
  52
  53 void Connection::FlagRecv() noexcept {
  54         recv_timer.Reset();
  55 }
  56
  57 bool Connection::ShouldPing() const noexcept {
  58         return !closed && send_timer.HitOnce();
  59 }
  60
  61 bool Connection::TimedOut() const noexcept {
  62         return recv_timer.HitOnce();
  63 }
  64
  65 void Connection::Update(int dt) {
  66         send_timer.Update(dt);
  67         recv_timer.Update(dt);
  68         if (TimedOut()) {
  69                 Close();
  70                 if (HasHandler()) {
  71                         Handler().OnTimeout();
  72                 }
  73         }
  74 }
  75
  76
  77 uint16_t Connection::Send(UDPpacket &udp_pack, UDPsocket sock) {
  78         Packet &pack = *reinterpret_cast<Packet *>(udp_pack.data);
  79         pack.header.ctrl = ctrl_out;
  80         uint16_t seq = ctrl_out.seq++;
  81
  82         udp_pack.address = addr;
  83         if (SDLNet_UDP_Send(sock, -1, &udp_pack) == 0) {
  84                 throw NetError("SDLNet_UDP_Send");
  85         }
  86
  87         FlagSend();
  88         return seq;
  89 }
  90
  91 void Connection::Received(const UDPpacket &udp_pack) {
  92         Packet &pack = *reinterpret_cast<Packet *>(udp_pack.data);
  93
  94         // ack to the remote
  95         int16_t diff = int16_t(pack.header.ctrl.seq) - int16_t(ctrl_out.ack);
  96         if (diff > 0) {
  97                 if (diff >= 32) {
  98                         ctrl_out.hist = 0;
  99                 } else {
 100                         ctrl_out.hist <<= diff;
 101                         ctrl_out.hist |= 1 << (diff - 1);
 102                 }
 103         } else if (diff < 0 && diff >= -32) {
 104                 ctrl_out.hist |= 1 << (-diff - 1);
 105         }
 106         ctrl_out.ack = pack.header.ctrl.seq;
 107         FlagRecv();
 108
 109         if (!HasHandler()) {
 110                 return;
 111         }
 112
 113         Packet::TControl ctrl_new = pack.header.ctrl;
 114         Handler().Handle(udp_pack);
 115
 116         if (diff > 0) {
 117                 // if the packet holds more recent information
 118                 // check if remote failed to ack one of our packets
 119                 diff = int16_t(ctrl_new.ack) - int16_t(ctrl_in.ack);
 120                 // should always be true, but you never know…
 121                 if (diff > 0) {
 122                         for (int i = 0; i < diff; ++i) {
 123                                 if (i > 32 || (i < 32 && (ctrl_in.hist & (1 << (31 - i))) == 0)) {
 124                                         Handler().PacketLost(ctrl_in.ack - 32 + i);
 125                                 }
 126                         }
 127                 }
 128                 // check for newly ack'd packets
 129                 for (uint16_t s = ctrl_new.AckBegin(); s != ctrl_new.AckEnd(); --s) {
 130                         if (ctrl_new.Acks(s) && !ctrl_in.Acks(s)) {
 131                                 Handler().PacketReceived(s);
 132                         }
 133                 }
 134                 ctrl_in = ctrl_new;
 135         }
 136 }
 137
 138 bool Packet::TControl::Acks(uint16_t s) const noexcept {
 139         int16_t diff = int16_t(ack) - int16_t(s);
 140         if (diff == 0) return true;
 141         if (diff < 0 || diff > 32) return false;
 142         return (hist & (1 << (diff - 1))) != 0;
 143 }
 144
 145 uint16_t Connection::SendPing(UDPpacket &udp_pack, UDPsocket sock) {
 146         Packet::Make<Packet::Ping>(udp_pack);
 147         return Send(udp_pack, sock);
 148 }
 149
 150
 151 ConnectionHandler::ConnectionHandler()
 152 : packets_lost(0)
 153 , packets_received(0)
 154 , packet_loss(0.0f) {
 155
 156 }
 157
 158 void ConnectionHandler::PacketLost(uint16_t seq) {
 159         OnPacketLost(seq);
 160         ++packets_lost;
 161         UpdatePacketLoss();
 162 }
 163
 164 void ConnectionHandler::PacketReceived(uint16_t seq) {
 165         OnPacketReceived(seq);
 166         ++packets_received;
 167         UpdatePacketLoss();
 168 }
 169
 170 void ConnectionHandler::UpdatePacketLoss() noexcept {
 171         unsigned int packets_total = packets_lost + packets_received;
 172         if (packets_total >= 256) {
 173                 packet_loss = float(packets_lost) / float(packets_total);
 174                 packets_lost = 0;
 175                 packets_received = 0;
 176         }
 177 }
 178
 179
 180 ostream &operator <<(ostream &out, const IPaddress &addr) {
 181         const unsigned char *host = reinterpret_cast<const unsigned char *>(&addr.host);
 182         out << int(host[0])
 183                 << '.' << int(host[1])
 184                 << '.' << int(host[2])
 185                 << '.' << int(host[3]);
 186         if (addr.port) {
 187                 out << ':' << SDLNet_Read16(&addr.port);
 188         }
 189         return out;
 190 }
 191
 192
 193 const char *Packet::Type2String(uint8_t t) noexcept {
 194         switch (t) {
 195                 case Ping::TYPE:
 196                         return "Ping";
 197                 case Login::TYPE:
 198                         return "Login";
 199                 case Join::TYPE:
 200                         return "Join";
 201                 case Part::TYPE:
 202                         return "Part";
 203                 case PlayerUpdate::TYPE:
 204                         return "PlayerUpdate";
 205                 case SpawnEntity::TYPE:
 206                         return "SpawnEntity";
 207                 case DespawnEntity::TYPE:
 208                         return "DespawnEntity";
 209                 case EntityUpdate::TYPE:
 210                         return "EntityUpdate";
 211                 case PlayerCorrection::TYPE:
 212                         return "PlayerCorrection";
 213                 case ChunkBegin::TYPE:
 214                         return "ChunkBegin";
 215                 case ChunkData::TYPE:
 216                         return "ChunkData";
 217                 case BlockUpdate::TYPE:
 218                         return "BlockUpdate";
 219                 case Message::TYPE:
 220                         return "Message";
 221                 default:
 222                         return "Unknown";
 223         }
 224 }
 225
 226 template<class T>
 227 void Packet::Payload::Write(const T &src, size_t off) noexcept {
 228         if ((length - off) < sizeof(T)) {
 229                 // dismiss out of bounds write
 230                 return;
 231         }
 232         *reinterpret_cast<T *>(&data[off]) = src;
 233 }
 234
 235 template<class T>
 236 void Packet::Payload::Read(T &dst, size_t off) const noexcept {
 237         if ((length - off) < sizeof(T)) {
 238                 // dismiss out of bounds read
 239                 return;
 240         }
 241         dst = *reinterpret_cast<T *>(&data[off]);
 242 }
 243
 244 void Packet::Payload::WriteString(const string &src, size_t off, size_t maxlen) noexcept {
 245         uint8_t *dst = &data[off];
 246         size_t len = min(maxlen, length - off);
 247         if (src.size() < len) {
 248                 memset(dst, '\0', len);
 249                 memcpy(dst, src.c_str(), src.size());
 250         } else {
 251                 memcpy(dst, src.c_str(), len);
 252         }
 253 }
 254
 255 void Packet::Payload::ReadString(string &dst, size_t off, size_t maxlen) const noexcept {
 256         size_t len = min(maxlen, length - off);
 257         dst.clear();
 258         dst.reserve(len);
 259         for (size_t i = 0; i < len && data[off + i] != '\0'; ++i) {
 260                 dst.push_back(data[off + i]);
 261         }
 262 }
 263
 264
 265 void Packet::Login::WritePlayerName(const string &name) noexcept {
 266         WriteString(name, 0, 32);
 267 }
 268
 269 void Packet::Login::ReadPlayerName(string &name) const noexcept {
 270         ReadString(name, 0, 32);
 271 }
 272
 273 void Packet::Join::WritePlayer(const Entity &player) noexcept {
 274         Write(player.ID(), 0);
 275         Write(player.GetState(), 4);
 276 }
 277
 278 void Packet::Join::ReadPlayerID(uint32_t &id) const noexcept {
 279         Read(id, 0);
 280 }
 281
 282 void Packet::Join::ReadPlayerState(EntityState &state) const noexcept {
 283         Read(state, 4);
 284 }
 285
 286 void Packet::Join::WriteWorldName(const string &name) noexcept {
 287         WriteString(name, 68, 32);
 288 }
 289
 290 void Packet::Join::ReadWorldName(string &name) const noexcept {
 291         ReadString(name, 68, 32);
 292 }
 293
 294 void Packet::PlayerUpdate::WritePredictedState(const EntityState &state) noexcept {
 295         Write(state, 0);
 296 }
 297
 298 void Packet::PlayerUpdate::ReadPredictedState(EntityState &state) const noexcept {
 299         Read(state, 0);
 300 }
 301
 302 void Packet::PlayerUpdate::WriteMovement(const glm::vec3 &mov) noexcept {
 303         glm::ivec3 conv = clamp(glm::ivec3(mov * 32767.0f), -32767, 32767);
 304         Write(int16_t(conv.x), 64);
 305         Write(int16_t(conv.y), 66);
 306         Write(int16_t(conv.z), 68);
 307 }
 308
 309 void Packet::PlayerUpdate::ReadMovement(glm::vec3 &mov) const noexcept {
 310         int16_t x, y, z;
 311         Read(x, 64);
 312         Read(y, 66);
 313         Read(z, 68);
 314         mov = glm::vec3(x, y, z) * .00003051850947599719f;
 315 }
 316
 317 void Packet::PlayerUpdate::WritePitch(float pitch) noexcept {
 318         int16_t conv = pitch * 20860.12008116853786870640f;
 319         Write(conv, 70);
 320 }
 321
 322 void Packet::PlayerUpdate::ReadPitch(float &pitch) const noexcept {
 323         int16_t conv = 0;
 324         Read(conv, 70);
 325         pitch = conv * .00004793836258415163f;
 326 }
 327
 328 void Packet::PlayerUpdate::WriteYaw(float yaw) noexcept {
 329         int16_t conv = yaw * 10430.06004058426893435320f;
 330         Write(conv, 72);
 331 }
 332
 333 void Packet::PlayerUpdate::ReadYaw(float &yaw) const noexcept {
 334         int16_t conv = 0;
 335         Read(conv, 72);
 336         yaw = conv * .00009587672516830326f;
 337 }
 338
 339 void Packet::PlayerUpdate::WriteActions(uint8_t actions) noexcept {
 340         Write(actions, 74);
 341 }
 342
 343 void Packet::PlayerUpdate::ReadActions(uint8_t &actions) const noexcept {
 344         Read(actions, 74);
 345 }
 346
 347 void Packet::PlayerUpdate::WriteSlot(uint8_t slot) noexcept {
 348         Write(slot, 75);
 349 }
 350
 351 void Packet::PlayerUpdate::ReadSlot(uint8_t &slot) const noexcept {
 352         Read(slot, 75);
 353 }
 354
 355 void Packet::SpawnEntity::WriteEntity(const Entity &e) noexcept {
 356         Write(e.ID(), 0);
 357         if (e.GetModel()) {
 358                 Write(e.GetModel().GetModel().ID(), 4);
 359         } else {
 360                 Write(uint32_t(0), 4);
 361         }
 362         Write(e.GetState(), 8);
 363         Write(e.Bounds(), 72);
 364         uint32_t flags = 0;
 365         if (e.WorldCollidable()) {
 366                 flags |= 1;
 367         }
 368         Write(flags, 96);
 369         WriteString(e.Name(), 100, 32);
 370 }
 371
 372 void Packet::SpawnEntity::ReadEntityID(uint32_t &id) const noexcept {
 373         Read(id, 0);
 374 }
 375
 376 void Packet::SpawnEntity::ReadSkeletonID(uint32_t &id) const noexcept {
 377         Read(id, 4);
 378 }
 379
 380 void Packet::SpawnEntity::ReadEntity(Entity &e) const noexcept {
 381         EntityState state;
 382         AABB bounds;
 383         uint32_t flags = 0;
 384         string name;
 385
 386         Read(state, 8);
 387         Read(bounds, 72);
 388         Read(flags, 96);
 389         ReadString(name, 100, 32);
 390
 391         e.SetState(state);
 392         e.Bounds(bounds);
 393         e.WorldCollidable(flags & 1);
 394         e.Name(name);
 395 }
 396
 397 void Packet::DespawnEntity::WriteEntityID(uint32_t id) noexcept {
 398         Write(id, 0);
 399 }
 400
 401 void Packet::DespawnEntity::ReadEntityID(uint32_t &id) const noexcept {
 402         Read(id, 0);
 403 }
 404
 405 void Packet::EntityUpdate::WriteEntityCount(uint32_t count) noexcept {
 406         Write(count, 0);
 407 }
 408
 409 void Packet::EntityUpdate::ReadEntityCount(uint32_t &count) const noexcept {
 410         Read(count, 0);
 411 }
 412
 413 void Packet::EntityUpdate::WriteEntity(const Entity &entity, uint32_t num) noexcept {
 414         uint32_t off = GetSize(num);
 415
 416         Write(entity.ID(), off);
 417         Write(entity.GetState(), off + 4);
 418 }
 419
 420 void Packet::EntityUpdate::ReadEntityID(uint32_t &id, uint32_t num) const noexcept {
 421         uint32_t off = GetSize(num);
 422         Read(id, off);
 423 }
 424
 425 void Packet::EntityUpdate::ReadEntityState(EntityState &state, uint32_t num) const noexcept {
 426         uint32_t off = GetSize(num);
 427         Read(state, off + 4);
 428 }
 429
 430 void Packet::PlayerCorrection::WritePacketSeq(std::uint16_t s) noexcept {
 431         Write(s, 0);
 432 }
 433
 434 void Packet::PlayerCorrection::ReadPacketSeq(std::uint16_t &s) const noexcept {
 435         Read(s, 0);
 436 }
 437
 438 void Packet::PlayerCorrection::WritePlayer(const Entity &player) noexcept {
 439         Write(player.GetState(), 2);
 440 }
 441
 442 void Packet::PlayerCorrection::ReadPlayerState(EntityState &state) const noexcept {
 443         Read(state, 2);
 444 }
 445
 446 void Packet::ChunkBegin::WriteTransmissionId(uint32_t id) noexcept {
 447         Write(id, 0);
 448 }
 449
 450 void Packet::ChunkBegin::ReadTransmissionId(uint32_t &id) const noexcept {
 451         Read(id, 0);
 452 }
 453
 454 void Packet::ChunkBegin::WriteFlags(uint32_t f) noexcept {
 455         Write(f, 4);
 456 }
 457
 458 void Packet::ChunkBegin::ReadFlags(uint32_t &f) const noexcept {
 459         Read(f, 4);
 460 }
 461
 462 void Packet::ChunkBegin::WriteChunkCoords(const glm::ivec3 &pos) noexcept {
 463         Write(pos, 8);
 464 }
 465
 466 void Packet::ChunkBegin::ReadChunkCoords(glm::ivec3 &pos) const noexcept {
 467         Read(pos, 8);
 468 }
 469
 470 void Packet::ChunkBegin::WriteDataSize(uint32_t s) noexcept {
 471         Write(s, 20);
 472 }
 473
 474 void Packet::ChunkBegin::ReadDataSize(uint32_t &s) const noexcept {
 475         Read(s, 20);
 476 }
 477
 478 void Packet::ChunkData::WriteTransmissionId(uint32_t id) noexcept {
 479         Write(id, 0);
 480 }
 481
 482 void Packet::ChunkData::ReadTransmissionId(uint32_t &id) const noexcept {
 483         Read(id, 0);
 484 }
 485
 486 void Packet::ChunkData::WriteDataOffset(uint32_t o) noexcept {
 487         Write(o, 4);
 488 }
 489
 490 void Packet::ChunkData::ReadDataOffset(uint32_t &o) const noexcept {
 491         Read(o, 4);
 492 }
 493
 494 void Packet::ChunkData::WriteDataSize(uint32_t s) noexcept {
 495         Write(s, 8);
 496 }
 497
 498 void Packet::ChunkData::ReadDataSize(uint32_t &s) const noexcept {
 499         Read(s, 8);
 500 }
 501
 502 void Packet::ChunkData::WriteData(const uint8_t *d, size_t l) noexcept {
 503         size_t len = min(length - 12, l);
 504         memcpy(&data[12], d, len);
 505 }
 506
 507 void Packet::ChunkData::ReadData(uint8_t *d, size_t l) const noexcept {
 508         size_t len = min(length - 12, l);
 509         memcpy(d, &data[12], len);
 510 }
 511
 512 void Packet::BlockUpdate::WriteChunkCoords(const glm::ivec3 &coords) noexcept {
 513         Write(coords, 0);
 514 }
 515
 516 void Packet::BlockUpdate::ReadChunkCoords(glm::ivec3 &coords) const noexcept {
 517         Read(coords, 0);
 518 }
 519
 520 void Packet::BlockUpdate::WriteBlockCount(uint32_t count) noexcept {
 521         Write(count, 12);
 522 }
 523
 524 void Packet::BlockUpdate::ReadBlockCount(uint32_t &count) const noexcept {
 525         Read(count, 12);
 526 }
 527
 528 void Packet::BlockUpdate::WriteIndex(uint16_t index, uint32_t num) noexcept {
 529         uint32_t off = GetSize(num);
 530         Write(index, off);
 531 }
 532
 533 void Packet::BlockUpdate::ReadIndex(uint16_t &index, uint32_t num) const noexcept {
 534         uint32_t off = GetSize(num);
 535         Read(index, off);
 536 }
 537
 538 void Packet::BlockUpdate::WriteBlock(const Block &block, uint32_t num) noexcept {
 539         uint32_t off = GetSize(num) + 2;
 540         Write(block, off);
 541 }
 542
 543 void Packet::BlockUpdate::ReadBlock(Block &block, uint32_t num) const noexcept {
 544         uint32_t off = GetSize(num) + 2;
 545         Read(block, off);
 546 }
 547
 548 void Packet::Message::WriteType(uint8_t type) noexcept {
 549         Write(type, 0);
 550 }
 551
 552 void Packet::Message::ReadType(uint8_t &type) const noexcept {
 553         Read(type, 0);
 554 }
 555
 556 void Packet::Message::WriteReferral(uint32_t ref) noexcept {
 557         Write(ref, 1);
 558 }
 559
 560 void Packet::Message::ReadReferral(uint32_t &ref) const noexcept {
 561         Read(ref, 1);
 562 }
 563
 564 void Packet::Message::WriteMessage(const string &msg) noexcept {
 565         WriteString(msg, 5, MAX_MESSAGE_LEN);
 566 }
 567
 568 void Packet::Message::ReadMessage(string &msg) const noexcept {
 569         ReadString(msg, 5, MAX_MESSAGE_LEN);
 570 }
 571
 572
 573 void ConnectionHandler::Handle(const UDPpacket &udp_pack) {
 574         const Packet &pack = *reinterpret_cast<const Packet *>(udp_pack.data);
 575         switch (pack.Type()) {
 576                 case Packet::Ping::TYPE:
 577                         On(Packet::As<Packet::Ping>(udp_pack));
 578                         break;
 579                 case Packet::Login::TYPE:
 580                         On(Packet::As<Packet::Login>(udp_pack));
 581                         break;
 582                 case Packet::Join::TYPE:
 583                         On(Packet::As<Packet::Join>(udp_pack));
 584                         break;
 585                 case Packet::Part::TYPE:
 586                         On(Packet::As<Packet::Part>(udp_pack));
 587                         break;
 588                 case Packet::PlayerUpdate::TYPE:
 589                         On(Packet::As<Packet::PlayerUpdate>(udp_pack));
 590                         break;
 591                 case Packet::SpawnEntity::TYPE:
 592                         On(Packet::As<Packet::SpawnEntity>(udp_pack));
 593                         break;
 594                 case Packet::DespawnEntity::TYPE:
 595                         On(Packet::As<Packet::DespawnEntity>(udp_pack));
 596                         break;
 597                 case Packet::EntityUpdate::TYPE:
 598                         On(Packet::As<Packet::EntityUpdate>(udp_pack));
 599                         break;
 600                 case Packet::PlayerCorrection::TYPE:
 601                         On(Packet::As<Packet::PlayerCorrection>(udp_pack));
 602                         break;
 603                 case Packet::ChunkBegin::TYPE:
 604                         On(Packet::As<Packet::ChunkBegin>(udp_pack));
 605                         break;
 606                 case Packet::ChunkData::TYPE:
 607                         On(Packet::As<Packet::ChunkData>(udp_pack));
 608                         break;
 609                 case Packet::BlockUpdate::TYPE:
 610                         On(Packet::As<Packet::BlockUpdate>(udp_pack));
 611                         break;
 612                 case Packet::Message::TYPE:
 613                         On(Packet::As<Packet::Message>(udp_pack));
 614                         break;
 615                 default:
 616                         // drop unknown or unhandled packets
 617                         break;
 618         }
 619 }
 620
 621 }