src/network/serverpackethandler.cpp

   1 /*
   2 Minetest
   3 Copyright (C) 2015 nerzhul, Loic Blot <loic.blot@unix-experience.fr>
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU Lesser General Public License as published by
   7 the Free Software Foundation; either version 2.1 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU Lesser General Public License for more details.
  14
  15 You should have received a copy of the GNU Lesser General Public License along
  16 with this program; if not, write to the Free Software Foundation, Inc.,
  17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19
  20 #include "chatmessage.h"
  21 #include "server.h"
  22 #include "log.h"
  23 #include "emerge.h"
  24 #include "mapblock.h"
  25 #include "modchannels.h"
  26 #include "nodedef.h"
  27 #include "remoteplayer.h"
  28 #include "rollback_interface.h"
  29 #include "scripting_server.h"
  30 #include "settings.h"
  31 #include "tool.h"
  32 #include "version.h"
  33 #include "network/connection.h"
  34 #include "network/networkprotocol.h"
  35 #include "network/serveropcodes.h"
  36 #include "server/player_sao.h"
  37 #include "server/serverinventorymgr.h"
  38 #include "util/auth.h"
  39 #include "util/base64.h"
  40 #include "util/pointedthing.h"
  41 #include "util/serialize.h"
  42 #include "util/srp.h"
  43
  44 void Server::handleCommand_Deprecated(NetworkPacket* pkt)
  45 {
  46         infostream << "Server: " << toServerCommandTable[pkt->getCommand()].name
  47                 << " not supported anymore" << std::endl;
  48 }
  49
  50 void Server::handleCommand_Init(NetworkPacket* pkt)
  51 {
  52
  53         if(pkt->getSize() < 1)
  54                 return;
  55
  56         session_t peer_id = pkt->getPeerId();
  57         RemoteClient *client = getClient(peer_id, CS_Created);
  58
  59         Address addr;
  60         std::string addr_s;
  61         try {
  62                 addr = m_con->GetPeerAddress(peer_id);
  63                 addr_s = addr.serializeString();
  64         } catch (con::PeerNotFoundException &e) {
  65                 /*
  66                  * no peer for this packet found
  67                  * most common reason is peer timeout, e.g. peer didn't
  68                  * respond for some time, your server was overloaded or
  69                  * things like that.
  70                  */
  71                 infostream << "Server::ProcessData(): Canceling: peer " << peer_id <<
  72                         " not found" << std::endl;
  73                 return;
  74         }
  75
  76         if (client->getState() > CS_Created) {
  77                 verbosestream << "Server: Ignoring multiple TOSERVER_INITs from " <<
  78                         addr_s << " (peer_id=" << peer_id << ")" << std::endl;
  79                 return;
  80         }
  81
  82         client->setCachedAddress(addr);
  83
  84         verbosestream << "Server: Got TOSERVER_INIT from " << addr_s <<
  85                 " (peer_id=" << peer_id << ")" << std::endl;
  86
  87         // Do not allow multiple players in simple singleplayer mode.
  88         // This isn't a perfect way to do it, but will suffice for now
  89         if (m_simple_singleplayer_mode && m_clients.getClientIDs().size() > 1) {
  90                 infostream << "Server: Not allowing another client (" << addr_s <<
  91                         ") to connect in simple singleplayer mode" << std::endl;
  92                 DenyAccess(peer_id, SERVER_ACCESSDENIED_SINGLEPLAYER);
  93                 return;
  94         }
  95
  96         // First byte after command is maximum supported
  97         // serialization version
  98         u8 client_max;
  99         u16 supp_compr_modes;
 100         u16 min_net_proto_version = 0;
 101         u16 max_net_proto_version;
 102         std::string playerName;
 103
 104         *pkt >> client_max >> supp_compr_modes >> min_net_proto_version
 105                         >> max_net_proto_version >> playerName;
 106
 107         u8 our_max = SER_FMT_VER_HIGHEST_READ;
 108         // Use the highest version supported by both
 109         u8 depl_serial_v = std::min(client_max, our_max);
 110         // If it's lower than the lowest supported, give up.
 111         if (depl_serial_v < SER_FMT_VER_LOWEST_READ)
 112                 depl_serial_v = SER_FMT_VER_INVALID;
 113
 114         if (depl_serial_v == SER_FMT_VER_INVALID) {
 115                 actionstream << "Server: A mismatched client tried to connect from " <<
 116                         addr_s << " ser_fmt_max=" << (int)client_max << std::endl;
 117                 DenyAccess(peer_id, SERVER_ACCESSDENIED_WRONG_VERSION);
 118                 return;
 119         }
 120
 121         client->setPendingSerializationVersion(depl_serial_v);
 122
 123         /*
 124                 Read and check network protocol version
 125         */
 126
 127         u16 net_proto_version = 0;
 128
 129         // Figure out a working version if it is possible at all
 130         if (max_net_proto_version >= SERVER_PROTOCOL_VERSION_MIN ||
 131                         min_net_proto_version <= SERVER_PROTOCOL_VERSION_MAX) {
 132                 // If maximum is larger than our maximum, go with our maximum
 133                 if (max_net_proto_version > SERVER_PROTOCOL_VERSION_MAX)
 134                         net_proto_version = SERVER_PROTOCOL_VERSION_MAX;
 135                 // Else go with client's maximum
 136                 else
 137                         net_proto_version = max_net_proto_version;
 138         }
 139
 140         verbosestream << "Server: " << addr_s << ": Protocol version: min: "
 141                         << min_net_proto_version << ", max: " << max_net_proto_version
 142                         << ", chosen: " << net_proto_version << std::endl;
 143
 144         client->net_proto_version = net_proto_version;
 145
 146         if ((g_settings->getBool("strict_protocol_version_checking") &&
 147                         net_proto_version != LATEST_PROTOCOL_VERSION) ||
 148                         net_proto_version < SERVER_PROTOCOL_VERSION_MIN ||
 149                         net_proto_version > SERVER_PROTOCOL_VERSION_MAX) {
 150                 actionstream << "Server: A mismatched client tried to connect from " <<
 151                         addr_s << " proto_max=" << (int)max_net_proto_version << std::endl;
 152                 DenyAccess(peer_id, SERVER_ACCESSDENIED_WRONG_VERSION);
 153                 return;
 154         }
 155
 156         /*
 157                 Validate player name
 158         */
 159         const char* playername = playerName.c_str();
 160
 161         size_t pns = playerName.size();
 162         if (pns == 0 || pns > PLAYERNAME_SIZE) {
 163                 actionstream << "Server: Player with " <<
 164                         ((pns > PLAYERNAME_SIZE) ? "a too long" : "an empty") <<
 165                         " name tried to connect from " << addr_s << std::endl;
 166                 DenyAccess(peer_id, SERVER_ACCESSDENIED_WRONG_NAME);
 167                 return;
 168         }
 169
 170         if (!string_allowed(playerName, PLAYERNAME_ALLOWED_CHARS)) {
 171                 actionstream << "Server: Player with an invalid name tried to connect "
 172                         "from " << addr_s << std::endl;
 173                 DenyAccess(peer_id, SERVER_ACCESSDENIED_WRONG_CHARS_IN_NAME);
 174                 return;
 175         }
 176
 177         m_clients.setPlayerName(peer_id, playername);
 178         //TODO (later) case insensitivity
 179
 180         std::string legacyPlayerNameCasing = playerName;
 181
 182         if (!isSingleplayer() && strcasecmp(playername, "singleplayer") == 0) {
 183                 actionstream << "Server: Player with the name \"singleplayer\" tried "
 184                         "to connect from " << addr_s << std::endl;
 185                 DenyAccess(peer_id, SERVER_ACCESSDENIED_WRONG_NAME);
 186                 return;
 187         }
 188
 189         {
 190                 std::string reason;
 191                 if (m_script->on_prejoinplayer(playername, addr_s, &reason)) {
 192                         actionstream << "Server: Player with the name \"" << playerName <<
 193                                 "\" tried to connect from " << addr_s <<
 194                                 " but it was disallowed for the following reason: " << reason <<
 195                                 std::endl;
 196                         DenyAccess(peer_id, SERVER_ACCESSDENIED_CUSTOM_STRING, reason);
 197                         return;
 198                 }
 199         }
 200
 201         infostream << "Server: New connection: \"" << playerName << "\" from " <<
 202                 addr_s << " (peer_id=" << peer_id << ")" << std::endl;
 203
 204         // Enforce user limit.
 205         // Don't enforce for users that have some admin right or mod permits it.
 206         if (m_clients.isUserLimitReached() &&
 207                         playername != g_settings->get("name") &&
 208                         !m_script->can_bypass_userlimit(playername, addr_s)) {
 209                 actionstream << "Server: " << playername << " tried to join from " <<
 210                         addr_s << ", but there are already max_users=" <<
 211                         g_settings->getU16("max_users") << " players." << std::endl;
 212                 DenyAccess(peer_id, SERVER_ACCESSDENIED_TOO_MANY_USERS);
 213                 return;
 214         }
 215
 216         /*
 217                 Compose auth methods for answer
 218         */
 219         std::string encpwd; // encrypted Password field for the user
 220         bool has_auth = m_script->getAuth(playername, &encpwd, NULL);
 221         u32 auth_mechs = 0;
 222
 223         client->chosen_mech = AUTH_MECHANISM_NONE;
 224
 225         if (has_auth) {
 226                 std::vector<std::string> pwd_components = str_split(encpwd, '#');
 227                 if (pwd_components.size() == 4) {
 228                         if (pwd_components[1] == "1") { // 1 means srp
 229                                 auth_mechs |= AUTH_MECHANISM_SRP;
 230                                 client->enc_pwd = encpwd;
 231                         } else {
 232                                 actionstream << "User " << playername << " tried to log in, "
 233                                         "but password field was invalid (unknown mechcode)." <<
 234                                         std::endl;
 235                                 DenyAccess(peer_id, SERVER_ACCESSDENIED_SERVER_FAIL);
 236                                 return;
 237                         }
 238                 } else if (base64_is_valid(encpwd)) {
 239                         auth_mechs |= AUTH_MECHANISM_LEGACY_PASSWORD;
 240                         client->enc_pwd = encpwd;
 241                 } else {
 242                         actionstream << "User " << playername << " tried to log in, but "
 243                                 "password field was invalid (invalid base64)." << std::endl;
 244                         DenyAccess(peer_id, SERVER_ACCESSDENIED_SERVER_FAIL);
 245                         return;
 246                 }
 247         } else {
 248                 std::string default_password = g_settings->get("default_password");
 249                 if (default_password.length() == 0) {
 250                         auth_mechs |= AUTH_MECHANISM_FIRST_SRP;
 251                 } else {
 252                         // Take care of default passwords.
 253                         client->enc_pwd = get_encoded_srp_verifier(playerName, default_password);
 254                         auth_mechs |= AUTH_MECHANISM_SRP;
 255                         // Allocate player in db, but only on successful login.
 256                         client->create_player_on_auth_success = true;
 257                 }
 258         }
 259
 260         /*
 261                 Answer with a TOCLIENT_HELLO
 262         */
 263
 264         verbosestream << "Sending TOCLIENT_HELLO with auth method field: "
 265                 << auth_mechs << std::endl;
 266
 267         NetworkPacket resp_pkt(TOCLIENT_HELLO,
 268                 1 + 4 + legacyPlayerNameCasing.size(), peer_id);
 269
 270         u16 depl_compress_mode = NETPROTO_COMPRESSION_NONE;
 271         resp_pkt << depl_serial_v << depl_compress_mode << net_proto_version
 272                 << auth_mechs << legacyPlayerNameCasing;
 273
 274         Send(&resp_pkt);
 275
 276         client->allowed_auth_mechs = auth_mechs;
 277         client->setDeployedCompressionMode(depl_compress_mode);
 278
 279         m_clients.event(peer_id, CSE_Hello);
 280 }
 281
 282 void Server::handleCommand_Init2(NetworkPacket* pkt)
 283 {
 284         session_t peer_id = pkt->getPeerId();
 285         verbosestream << "Server: Got TOSERVER_INIT2 from " << peer_id << std::endl;
 286
 287         m_clients.event(peer_id, CSE_GotInit2);
 288         u16 protocol_version = m_clients.getProtocolVersion(peer_id);
 289
 290         std::string lang;
 291         if (pkt->getSize() > 0)
 292                 *pkt >> lang;
 293
 294         /*
 295                 Send some initialization data
 296         */
 297
 298         infostream << "Server: Sending content to " << getPlayerName(peer_id) <<
 299                 std::endl;
 300
 301         // Send item definitions
 302         SendItemDef(peer_id, m_itemdef, protocol_version);
 303
 304         // Send node definitions
 305         SendNodeDef(peer_id, m_nodedef, protocol_version);
 306
 307         m_clients.event(peer_id, CSE_SetDefinitionsSent);
 308
 309         // Send media announcement
 310         sendMediaAnnouncement(peer_id, lang);
 311
 312         RemoteClient *client = getClient(peer_id, CS_InitDone);
 313
 314         // Keep client language for server translations
 315         client->setLangCode(lang);
 316
 317         // Send active objects
 318         {
 319                 PlayerSAO *sao = getPlayerSAO(peer_id);
 320                 if (sao)
 321                         SendActiveObjectRemoveAdd(client, sao);
 322         }
 323
 324         // Send detached inventories
 325         sendDetachedInventories(peer_id, false);
 326
 327         // Send player movement settings
 328         SendMovement(peer_id);
 329
 330         // Send time of day
 331         u16 time = m_env->getTimeOfDay();
 332         float time_speed = g_settings->getFloat("time_speed");
 333         SendTimeOfDay(peer_id, time, time_speed);
 334
 335         SendCSMRestrictionFlags(peer_id);
 336
 337         // Warnings about protocol version can be issued here
 338         if (client->net_proto_version < LATEST_PROTOCOL_VERSION) {
 339                 SendChatMessage(peer_id, ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
 340                         L"# Server: WARNING: YOUR CLIENT'S VERSION MAY NOT BE FULLY COMPATIBLE "
 341                         L"WITH THIS SERVER!"));
 342         }
 343 }
 344
 345 void Server::handleCommand_RequestMedia(NetworkPacket* pkt)
 346 {
 347         std::vector<std::string> tosend;
 348         u16 numfiles;
 349
 350         *pkt >> numfiles;
 351
 352         session_t peer_id = pkt->getPeerId();
 353         infostream << "Sending " << numfiles << " files to " <<
 354                 getPlayerName(peer_id) << std::endl;
 355         verbosestream << "TOSERVER_REQUEST_MEDIA: " << std::endl;
 356
 357         for (u16 i = 0; i < numfiles; i++) {
 358                 std::string name;
 359
 360                 *pkt >> name;
 361
 362                 tosend.push_back(name);
 363                 verbosestream << "TOSERVER_REQUEST_MEDIA: requested file "
 364                                 << name << std::endl;
 365         }
 366
 367         sendRequestedMedia(peer_id, tosend);
 368 }
 369
 370 void Server::handleCommand_ClientReady(NetworkPacket* pkt)
 371 {
 372         session_t peer_id = pkt->getPeerId();
 373
 374         PlayerSAO* playersao = StageTwoClientInit(peer_id);
 375
 376         if (playersao == NULL) {
 377                 errorstream << "TOSERVER_CLIENT_READY stage 2 client init failed "
 378                         "peer_id=" << peer_id << std::endl;
 379                 DisconnectPeer(peer_id);
 380                 return;
 381         }
 382
 383
 384         if (pkt->getSize() < 8) {
 385                 errorstream << "TOSERVER_CLIENT_READY client sent inconsistent data, "
 386                         "disconnecting peer_id: " << peer_id << std::endl;
 387                 DisconnectPeer(peer_id);
 388                 return;
 389         }
 390
 391         u8 major_ver, minor_ver, patch_ver, reserved;
 392         std::string full_ver;
 393         *pkt >> major_ver >> minor_ver >> patch_ver >> reserved >> full_ver;
 394
 395         m_clients.setClientVersion(peer_id, major_ver, minor_ver, patch_ver,
 396                 full_ver);
 397
 398         if (pkt->getRemainingBytes() >= 2)
 399                 *pkt >> playersao->getPlayer()->formspec_version;
 400
 401         const std::vector<std::string> &players = m_clients.getPlayerNames();
 402         NetworkPacket list_pkt(TOCLIENT_UPDATE_PLAYER_LIST, 0, peer_id);
 403         list_pkt << (u8) PLAYER_LIST_INIT << (u16) players.size();
 404         for (const std::string &player: players) {
 405                 list_pkt <<  player;
 406         }
 407         m_clients.send(peer_id, 0, &list_pkt, true);
 408
 409         NetworkPacket notice_pkt(TOCLIENT_UPDATE_PLAYER_LIST, 0, PEER_ID_INEXISTENT);
 410         // (u16) 1 + std::string represents a pseudo vector serialization representation
 411         notice_pkt << (u8) PLAYER_LIST_ADD << (u16) 1 << std::string(playersao->getPlayer()->getName());
 412         m_clients.sendToAll(&notice_pkt);
 413         m_clients.event(peer_id, CSE_SetClientReady);
 414
 415         s64 last_login;
 416         m_script->getAuth(playersao->getPlayer()->getName(), nullptr, nullptr, &last_login);
 417         m_script->on_joinplayer(playersao, last_login);
 418
 419         // Send shutdown timer if shutdown has been scheduled
 420         if (m_shutdown_state.isTimerRunning()) {
 421                 SendChatMessage(peer_id, m_shutdown_state.getShutdownTimerMessage());
 422         }
 423 }
 424
 425 void Server::handleCommand_GotBlocks(NetworkPacket* pkt)
 426 {
 427         if (pkt->getSize() < 1)
 428                 return;
 429
 430         /*
 431                 [0] u16 command
 432                 [2] u8 count
 433                 [3] v3s16 pos_0
 434                 [3+6] v3s16 pos_1
 435                 ...
 436         */
 437
 438         u8 count;
 439         *pkt >> count;
 440
 441         if ((s16)pkt->getSize() < 1 + (int)count * 6) {
 442                 throw con::InvalidIncomingDataException
 443                                 ("GOTBLOCKS length is too short");
 444         }
 445
 446         m_clients.lock();
 447         RemoteClient *client = m_clients.lockedGetClientNoEx(pkt->getPeerId());
 448
 449         for (u16 i = 0; i < count; i++) {
 450                 v3s16 p;
 451                 *pkt >> p;
 452                 client->GotBlock(p);
 453         }
 454         m_clients.unlock();
 455 }
 456
 457 void Server::process_PlayerPos(RemotePlayer *player, PlayerSAO *playersao,
 458         NetworkPacket *pkt)
 459 {
 460         if (pkt->getRemainingBytes() < 12 + 12 + 4 + 4 + 4 + 1 + 1)
 461                 return;
 462
 463         v3s32 ps, ss;
 464         s32 f32pitch, f32yaw;
 465         u8 f32fov;
 466
 467         *pkt >> ps;
 468         *pkt >> ss;
 469         *pkt >> f32pitch;
 470         *pkt >> f32yaw;
 471
 472         f32 pitch = (f32)f32pitch / 100.0f;
 473         f32 yaw = (f32)f32yaw / 100.0f;
 474         u32 keyPressed = 0;
 475
 476         // default behavior (in case an old client doesn't send these)
 477         f32 fov = 0;
 478         u8 wanted_range = 0;
 479
 480         *pkt >> keyPressed;
 481         *pkt >> f32fov;
 482         fov = (f32)f32fov / 80.0f;
 483         *pkt >> wanted_range;
 484
 485         v3f position((f32)ps.X / 100.0f, (f32)ps.Y / 100.0f, (f32)ps.Z / 100.0f);
 486         v3f speed((f32)ss.X / 100.0f, (f32)ss.Y / 100.0f, (f32)ss.Z / 100.0f);
 487
 488         pitch = modulo360f(pitch);
 489         yaw = wrapDegrees_0_360(yaw);
 490
 491         if (!playersao->isAttached()) {
 492                 // Only update player positions when moving freely
 493                 // to not interfere with attachment handling
 494                 playersao->setBasePosition(position);
 495                 player->setSpeed(speed);
 496         }
 497         playersao->setLookPitch(pitch);
 498         playersao->setPlayerYaw(yaw);
 499         playersao->setFov(fov);
 500         playersao->setWantedRange(wanted_range);
 501
 502         player->keyPressed = keyPressed;
 503         player->control.up    = (keyPressed & (0x1 << 0));
 504         player->control.down  = (keyPressed & (0x1 << 1));
 505         player->control.left  = (keyPressed & (0x1 << 2));
 506         player->control.right = (keyPressed & (0x1 << 3));
 507         player->control.jump  = (keyPressed & (0x1 << 4));
 508         player->control.aux1  = (keyPressed & (0x1 << 5));
 509         player->control.sneak = (keyPressed & (0x1 << 6));
 510         player->control.dig   = (keyPressed & (0x1 << 7));
 511         player->control.place = (keyPressed & (0x1 << 8));
 512         player->control.zoom  = (keyPressed & (0x1 << 9));
 513
 514         if (playersao->checkMovementCheat()) {
 515                 // Call callbacks
 516                 m_script->on_cheat(playersao, "moved_too_fast");
 517                 SendMovePlayer(pkt->getPeerId());
 518         }
 519 }
 520
 521 void Server::handleCommand_PlayerPos(NetworkPacket* pkt)
 522 {
 523         session_t peer_id = pkt->getPeerId();
 524         RemotePlayer *player = m_env->getPlayer(peer_id);
 525         if (player == NULL) {
 526                 errorstream <<
 527                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 528                         peer_id << " disconnecting peer!" << std::endl;
 529                 DisconnectPeer(peer_id);
 530                 return;
 531         }
 532
 533         PlayerSAO *playersao = player->getPlayerSAO();
 534         if (playersao == NULL) {
 535                 errorstream <<
 536                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
 537                         peer_id << " disconnecting peer!" << std::endl;
 538                 DisconnectPeer(peer_id);
 539                 return;
 540         }
 541
 542         // If player is dead we don't care of this packet
 543         if (playersao->isDead()) {
 544                 verbosestream << "TOSERVER_PLAYERPOS: " << player->getName()
 545                                 << " is dead. Ignoring packet";
 546                 return;
 547         }
 548
 549         process_PlayerPos(player, playersao, pkt);
 550 }
 551
 552 void Server::handleCommand_DeletedBlocks(NetworkPacket* pkt)
 553 {
 554         if (pkt->getSize() < 1)
 555                 return;
 556
 557         /*
 558                 [0] u16 command
 559                 [2] u8 count
 560                 [3] v3s16 pos_0
 561                 [3+6] v3s16 pos_1
 562                 ...
 563         */
 564
 565         u8 count;
 566         *pkt >> count;
 567
 568         RemoteClient *client = getClient(pkt->getPeerId());
 569
 570         if ((s16)pkt->getSize() < 1 + (int)count * 6) {
 571                 throw con::InvalidIncomingDataException
 572                                 ("DELETEDBLOCKS length is too short");
 573         }
 574
 575         for (u16 i = 0; i < count; i++) {
 576                 v3s16 p;
 577                 *pkt >> p;
 578                 client->SetBlockNotSent(p);
 579         }
 580 }
 581
 582 void Server::handleCommand_InventoryAction(NetworkPacket* pkt)
 583 {
 584         session_t peer_id = pkt->getPeerId();
 585         RemotePlayer *player = m_env->getPlayer(peer_id);
 586
 587         if (player == NULL) {
 588                 errorstream <<
 589                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 590                         peer_id << " disconnecting peer!" << std::endl;
 591                 DisconnectPeer(peer_id);
 592                 return;
 593         }
 594
 595         PlayerSAO *playersao = player->getPlayerSAO();
 596         if (playersao == NULL) {
 597                 errorstream <<
 598                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
 599                         peer_id << " disconnecting peer!" << std::endl;
 600                 DisconnectPeer(peer_id);
 601                 return;
 602         }
 603
 604         // Strip command and create a stream
 605         std::string datastring(pkt->getString(0), pkt->getSize());
 606         verbosestream << "TOSERVER_INVENTORY_ACTION: data=" << datastring
 607                 << std::endl;
 608         std::istringstream is(datastring, std::ios_base::binary);
 609         // Create an action
 610         std::unique_ptr<InventoryAction> a(InventoryAction::deSerialize(is));
 611         if (!a) {
 612                 infostream << "TOSERVER_INVENTORY_ACTION: "
 613                                 << "InventoryAction::deSerialize() returned NULL"
 614                                 << std::endl;
 615                 return;
 616         }
 617
 618         // If something goes wrong, this player is to blame
 619         RollbackScopeActor rollback_scope(m_rollback,
 620                         std::string("player:")+player->getName());
 621
 622         /*
 623                 Note: Always set inventory not sent, to repair cases
 624                 where the client made a bad prediction.
 625         */
 626
 627         const bool player_has_interact = checkPriv(player->getName(), "interact");
 628
 629         auto check_inv_access = [player, player_has_interact] (
 630                         const InventoryLocation &loc) -> bool {
 631                 if (loc.type == InventoryLocation::CURRENT_PLAYER)
 632                         return false; // Only used internally on the client, never sent
 633                 if (loc.type == InventoryLocation::PLAYER) {
 634                         // Allow access to own inventory in all cases
 635                         return loc.name == player->getName();
 636                 }
 637
 638                 if (!player_has_interact) {
 639                         infostream << "Cannot modify foreign inventory: "
 640                                         << "No interact privilege" << std::endl;
 641                         return false;
 642                 }
 643                 return true;
 644         };
 645
 646         /*
 647                 Handle restrictions and special cases of the move action
 648         */
 649         if (a->getType() == IAction::Move) {
 650                 IMoveAction *ma = (IMoveAction*)a.get();
 651
 652                 ma->from_inv.applyCurrentPlayer(player->getName());
 653                 ma->to_inv.applyCurrentPlayer(player->getName());
 654
 655                 m_inventory_mgr->setInventoryModified(ma->from_inv);
 656                 if (ma->from_inv != ma->to_inv)
 657                         m_inventory_mgr->setInventoryModified(ma->to_inv);
 658
 659                 if (!check_inv_access(ma->from_inv) ||
 660                                 !check_inv_access(ma->to_inv))
 661                         return;
 662
 663                 InventoryLocation *remote = ma->from_inv.type == InventoryLocation::PLAYER ?
 664                         &ma->to_inv : &ma->from_inv;
 665
 666                 // Check for out-of-range interaction
 667                 if (remote->type == InventoryLocation::NODEMETA) {
 668                         v3f node_pos   = intToFloat(remote->p, BS);
 669                         v3f player_pos = player->getPlayerSAO()->getEyePosition();
 670                         f32 d = player_pos.getDistanceFrom(node_pos);
 671                         if (!checkInteractDistance(player, d, "inventory"))
 672                                 return;
 673                 }
 674
 675                 /*
 676                         Disable moving items out of craftpreview
 677                 */
 678                 if (ma->from_list == "craftpreview") {
 679                         infostream << "Ignoring IMoveAction from "
 680                                         << (ma->from_inv.dump()) << ":" << ma->from_list
 681                                         << " to " << (ma->to_inv.dump()) << ":" << ma->to_list
 682                                         << " because src is " << ma->from_list << std::endl;
 683                         return;
 684                 }
 685
 686                 /*
 687                         Disable moving items into craftresult and craftpreview
 688                 */
 689                 if (ma->to_list == "craftpreview" || ma->to_list == "craftresult") {
 690                         infostream << "Ignoring IMoveAction from "
 691                                         << (ma->from_inv.dump()) << ":" << ma->from_list
 692                                         << " to " << (ma->to_inv.dump()) << ":" << ma->to_list
 693                                         << " because dst is " << ma->to_list << std::endl;
 694                         return;
 695                 }
 696         }
 697         /*
 698                 Handle restrictions and special cases of the drop action
 699         */
 700         else if (a->getType() == IAction::Drop) {
 701                 IDropAction *da = (IDropAction*)a.get();
 702
 703                 da->from_inv.applyCurrentPlayer(player->getName());
 704
 705                 m_inventory_mgr->setInventoryModified(da->from_inv);
 706
 707                 /*
 708                         Disable dropping items out of craftpreview
 709                 */
 710                 if (da->from_list == "craftpreview") {
 711                         infostream << "Ignoring IDropAction from "
 712                                         << (da->from_inv.dump()) << ":" << da->from_list
 713                                         << " because src is " << da->from_list << std::endl;
 714                         return;
 715                 }
 716
 717                 // Disallow dropping items if not allowed to interact
 718                 if (!player_has_interact || !check_inv_access(da->from_inv))
 719                         return;
 720
 721                 // Disallow dropping items if dead
 722                 if (playersao->isDead()) {
 723                         infostream << "Ignoring IDropAction from "
 724                                         << (da->from_inv.dump()) << ":" << da->from_list
 725                                         << " because player is dead." << std::endl;
 726                         return;
 727                 }
 728         }
 729         /*
 730                 Handle restrictions and special cases of the craft action
 731         */
 732         else if (a->getType() == IAction::Craft) {
 733                 ICraftAction *ca = (ICraftAction*)a.get();
 734
 735                 ca->craft_inv.applyCurrentPlayer(player->getName());
 736
 737                 m_inventory_mgr->setInventoryModified(ca->craft_inv);
 738
 739                 // Disallow crafting if not allowed to interact
 740                 if (!player_has_interact) {
 741                         infostream << "Cannot craft: "
 742                                         << "No interact privilege" << std::endl;
 743                         return;
 744                 }
 745
 746                 if (!check_inv_access(ca->craft_inv))
 747                         return;
 748         } else {
 749                 // Unknown action. Ignored.
 750                 return;
 751         }
 752
 753         // Do the action
 754         a->apply(m_inventory_mgr.get(), playersao, this);
 755 }
 756
 757 void Server::handleCommand_ChatMessage(NetworkPacket* pkt)
 758 {
 759         std::wstring message;
 760         *pkt >> message;
 761
 762         session_t peer_id = pkt->getPeerId();
 763         RemotePlayer *player = m_env->getPlayer(peer_id);
 764         if (player == NULL) {
 765                 errorstream <<
 766                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 767                         peer_id << " disconnecting peer!" << std::endl;
 768                 DisconnectPeer(peer_id);
 769                 return;
 770         }
 771
 772         std::string name = player->getName();
 773
 774         std::wstring answer_to_sender = handleChat(name, message, true, player);
 775         if (!answer_to_sender.empty()) {
 776                 // Send the answer to sender
 777                 SendChatMessage(peer_id, ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
 778                         answer_to_sender));
 779         }
 780 }
 781
 782 void Server::handleCommand_Damage(NetworkPacket* pkt)
 783 {
 784         u16 damage;
 785
 786         *pkt >> damage;
 787
 788         session_t peer_id = pkt->getPeerId();
 789         RemotePlayer *player = m_env->getPlayer(peer_id);
 790
 791         if (player == NULL) {
 792                 errorstream <<
 793                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 794                         peer_id << " disconnecting peer!" << std::endl;
 795                 DisconnectPeer(peer_id);
 796                 return;
 797         }
 798
 799         PlayerSAO *playersao = player->getPlayerSAO();
 800         if (playersao == NULL) {
 801                 errorstream <<
 802                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
 803                         peer_id << " disconnecting peer!" << std::endl;
 804                 DisconnectPeer(peer_id);
 805                 return;
 806         }
 807
 808         if (!playersao->isImmortal()) {
 809                 if (playersao->isDead()) {
 810                         verbosestream << "Server::ProcessData(): Info: "
 811                                 "Ignoring damage as player " << player->getName()
 812                                 << " is already dead." << std::endl;
 813                         return;
 814                 }
 815
 816                 actionstream << player->getName() << " damaged by "
 817                                 << (int)damage << " hp at " << PP(playersao->getBasePosition() / BS)
 818                                 << std::endl;
 819
 820                 PlayerHPChangeReason reason(PlayerHPChangeReason::FALL);
 821                 playersao->setHP((s32)playersao->getHP() - (s32)damage, reason);
 822                 SendPlayerHPOrDie(playersao, reason);
 823         }
 824 }
 825
 826 void Server::handleCommand_PlayerItem(NetworkPacket* pkt)
 827 {
 828         if (pkt->getSize() < 2)
 829                 return;
 830
 831         session_t peer_id = pkt->getPeerId();
 832         RemotePlayer *player = m_env->getPlayer(peer_id);
 833
 834         if (player == NULL) {
 835                 errorstream <<
 836                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 837                         peer_id << " disconnecting peer!" << std::endl;
 838                 DisconnectPeer(peer_id);
 839                 return;
 840         }
 841
 842         PlayerSAO *playersao = player->getPlayerSAO();
 843         if (playersao == NULL) {
 844                 errorstream <<
 845                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
 846                         peer_id << " disconnecting peer!" << std::endl;
 847                 DisconnectPeer(peer_id);
 848                 return;
 849         }
 850
 851         u16 item;
 852
 853         *pkt >> item;
 854
 855         if (item >= player->getHotbarItemcount()) {
 856                 actionstream << "Player: " << player->getName()
 857                         << " tried to access item=" << item
 858                         << " out of hotbar_itemcount="
 859                         << player->getHotbarItemcount()
 860                         << "; ignoring." << std::endl;
 861                 return;
 862         }
 863
 864         playersao->getPlayer()->setWieldIndex(item);
 865 }
 866
 867 void Server::handleCommand_Respawn(NetworkPacket* pkt)
 868 {
 869         session_t peer_id = pkt->getPeerId();
 870         RemotePlayer *player = m_env->getPlayer(peer_id);
 871         if (player == NULL) {
 872                 errorstream <<
 873                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 874                         peer_id << " disconnecting peer!" << std::endl;
 875                 DisconnectPeer(peer_id);
 876                 return;
 877         }
 878
 879         PlayerSAO *playersao = player->getPlayerSAO();
 880         assert(playersao);
 881
 882         if (!playersao->isDead())
 883                 return;
 884
 885         RespawnPlayer(peer_id);
 886
 887         actionstream << player->getName() << " respawns at "
 888                         << PP(playersao->getBasePosition() / BS) << std::endl;
 889
 890         // ActiveObject is added to environment in AsyncRunStep after
 891         // the previous addition has been successfully removed
 892 }
 893
 894 bool Server::checkInteractDistance(RemotePlayer *player, const f32 d, const std::string &what)
 895 {
 896         ItemStack selected_item, hand_item;
 897         player->getWieldedItem(&selected_item, &hand_item);
 898         f32 max_d = BS * getToolRange(selected_item.getDefinition(m_itemdef),
 899                         hand_item.getDefinition(m_itemdef));
 900
 901         // Cube diagonal * 1.5 for maximal supported node extents:
 902         // sqrt(3) * 1.5 ≅ 2.6
 903         if (d > max_d + 2.6f * BS) {
 904                 actionstream << "Player " << player->getName()
 905                                 << " tried to access " << what
 906                                 << " from too far: "
 907                                 << "d=" << d << ", max_d=" << max_d
 908                                 << "; ignoring." << std::endl;
 909                 // Call callbacks
 910                 m_script->on_cheat(player->getPlayerSAO(), "interacted_too_far");
 911                 return false;
 912         }
 913         return true;
 914 }
 915
 916 void Server::handleCommand_Interact(NetworkPacket *pkt)
 917 {
 918         /*
 919                 [0] u16 command
 920                 [2] u8 action
 921                 [3] u16 item
 922                 [5] u32 length of the next item (plen)
 923                 [9] serialized PointedThing
 924                 [9 + plen] player position information
 925         */
 926
 927         InteractAction action;
 928         u16 item_i;
 929
 930         *pkt >> (u8 &)action;
 931         *pkt >> item_i;
 932
 933         std::istringstream tmp_is(pkt->readLongString(), std::ios::binary);
 934         PointedThing pointed;
 935         pointed.deSerialize(tmp_is);
 936
 937         verbosestream << "TOSERVER_INTERACT: action=" << (int)action << ", item="
 938                         << item_i << ", pointed=" << pointed.dump() << std::endl;
 939
 940         session_t peer_id = pkt->getPeerId();
 941         RemotePlayer *player = m_env->getPlayer(peer_id);
 942
 943         if (player == NULL) {
 944                 errorstream <<
 945                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 946                         peer_id << " disconnecting peer!" << std::endl;
 947                 DisconnectPeer(peer_id);
 948                 return;
 949         }
 950
 951         PlayerSAO *playersao = player->getPlayerSAO();
 952         if (playersao == NULL) {
 953                 errorstream <<
 954                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
 955                         peer_id << " disconnecting peer!" << std::endl;
 956                 DisconnectPeer(peer_id);
 957                 return;
 958         }
 959
 960         if (playersao->isDead()) {
 961                 actionstream << "Server: " << player->getName()
 962                                 << " tried to interact while dead; ignoring." << std::endl;
 963                 if (pointed.type == POINTEDTHING_NODE) {
 964                         // Re-send block to revert change on client-side
 965                         RemoteClient *client = getClient(peer_id);
 966                         v3s16 blockpos = getNodeBlockPos(pointed.node_undersurface);
 967                         client->SetBlockNotSent(blockpos);
 968                 }
 969                 // Call callbacks
 970                 m_script->on_cheat(playersao, "interacted_while_dead");
 971                 return;
 972         }
 973
 974         process_PlayerPos(player, playersao, pkt);
 975
 976         v3f player_pos = playersao->getLastGoodPosition();
 977
 978         // Update wielded item
 979
 980         if (item_i >= player->getHotbarItemcount()) {
 981                 actionstream << "Player: " << player->getName()
 982                         << " tried to access item=" << item_i
 983                         << " out of hotbar_itemcount="
 984                         << player->getHotbarItemcount()
 985                         << "; ignoring." << std::endl;
 986                 return;
 987         }
 988
 989         playersao->getPlayer()->setWieldIndex(item_i);
 990
 991         // Get pointed to object (NULL if not POINTEDTYPE_OBJECT)
 992         ServerActiveObject *pointed_object = NULL;
 993         if (pointed.type == POINTEDTHING_OBJECT) {
 994                 pointed_object = m_env->getActiveObject(pointed.object_id);
 995                 if (pointed_object == NULL) {
 996                         verbosestream << "TOSERVER_INTERACT: "
 997                                 "pointed object is NULL" << std::endl;
 998                         return;
 999                 }
1000
1001         }
1002
1003         /*
1004                 Make sure the player is allowed to do it
1005         */
1006         if (!checkPriv(player->getName(), "interact")) {
1007                 actionstream << player->getName() << " attempted to interact with " <<
1008                                 pointed.dump() << " without 'interact' privilege" << std::endl;
1009
1010                 if (pointed.type != POINTEDTHING_NODE)
1011                         return;
1012
1013                 // Re-send block to revert change on client-side
1014                 RemoteClient *client = getClient(peer_id);
1015                 // Digging completed -> under
1016                 if (action == INTERACT_DIGGING_COMPLETED) {
1017                         v3s16 blockpos = getNodeBlockPos(pointed.node_undersurface);
1018                         client->SetBlockNotSent(blockpos);
1019                 }
1020                 // Placement -> above
1021                 else if (action == INTERACT_PLACE) {
1022                         v3s16 blockpos = getNodeBlockPos(pointed.node_abovesurface);
1023                         client->SetBlockNotSent(blockpos);
1024                 }
1025                 return;
1026         }
1027
1028         /*
1029                 Check that target is reasonably close
1030         */
1031         static thread_local const bool enable_anticheat =
1032                         !g_settings->getBool("disable_anticheat");
1033
1034         if ((action == INTERACT_START_DIGGING || action == INTERACT_DIGGING_COMPLETED ||
1035                         action == INTERACT_PLACE || action == INTERACT_USE) &&
1036                         enable_anticheat && !isSingleplayer()) {
1037                 v3f target_pos = player_pos;
1038                 if (pointed.type == POINTEDTHING_NODE) {
1039                         target_pos = intToFloat(pointed.node_undersurface, BS);
1040                 } else if (pointed.type == POINTEDTHING_OBJECT) {
1041                         target_pos = pointed_object->getBasePosition();
1042                 }
1043                 float d = playersao->getEyePosition().getDistanceFrom(target_pos);
1044
1045                 if (!checkInteractDistance(player, d, pointed.dump())) {
1046                         if (pointed.type == POINTEDTHING_NODE) {
1047                                 // Re-send block to revert change on client-side
1048                                 RemoteClient *client = getClient(peer_id);
1049                                 v3s16 blockpos = getNodeBlockPos(pointed.node_undersurface);
1050                                 client->SetBlockNotSent(blockpos);
1051                         }
1052                         return;
1053                 }
1054         }
1055
1056         /*
1057                 If something goes wrong, this player is to blame
1058         */
1059         RollbackScopeActor rollback_scope(m_rollback,
1060                         std::string("player:")+player->getName());
1061
1062         switch (action) {
1063         // Start digging or punch object
1064         case INTERACT_START_DIGGING: {
1065                 if (pointed.type == POINTEDTHING_NODE) {
1066                         MapNode n(CONTENT_IGNORE);
1067                         bool pos_ok;
1068
1069                         v3s16 p_under = pointed.node_undersurface;
1070                         n = m_env->getMap().getNode(p_under, &pos_ok);
1071                         if (!pos_ok) {
1072                                 infostream << "Server: Not punching: Node not found. "
1073                                         "Adding block to emerge queue." << std::endl;
1074                                 m_emerge->enqueueBlockEmerge(peer_id,
1075                                         getNodeBlockPos(pointed.node_abovesurface), false);
1076                         }
1077
1078                         if (n.getContent() != CONTENT_IGNORE)
1079                                 m_script->node_on_punch(p_under, n, playersao, pointed);
1080
1081                         // Cheat prevention
1082                         playersao->noCheatDigStart(p_under);
1083
1084                         return;
1085                 }
1086
1087                 // Skip if the object can't be interacted with anymore
1088                 if (pointed.type != POINTEDTHING_OBJECT || pointed_object->isGone())
1089                         return;
1090
1091                 ItemStack selected_item, hand_item;
1092                 ItemStack tool_item = playersao->getWieldedItem(&selected_item, &hand_item);
1093                 ToolCapabilities toolcap =
1094                                 tool_item.getToolCapabilities(m_itemdef);
1095                 v3f dir = (pointed_object->getBasePosition() -
1096                                 (playersao->getBasePosition() + playersao->getEyeOffset())
1097                                         ).normalize();
1098                 float time_from_last_punch =
1099                         playersao->resetTimeFromLastPunch();
1100
1101                 u16 src_original_hp = pointed_object->getHP();
1102                 u16 dst_origin_hp = playersao->getHP();
1103
1104                 u16 wear = pointed_object->punch(dir, &toolcap, playersao,
1105                                 time_from_last_punch);
1106
1107                 // Callback may have changed item, so get it again
1108                 playersao->getWieldedItem(&selected_item);
1109                 bool changed = selected_item.addWear(wear, m_itemdef);
1110                 if (changed)
1111                         playersao->setWieldedItem(selected_item);
1112
1113                 // If the object is a player and its HP changed
1114                 if (src_original_hp != pointed_object->getHP() &&
1115                                 pointed_object->getType() == ACTIVEOBJECT_TYPE_PLAYER) {
1116                         SendPlayerHPOrDie((PlayerSAO *)pointed_object,
1117                                         PlayerHPChangeReason(PlayerHPChangeReason::PLAYER_PUNCH, playersao));
1118                 }
1119
1120                 // If the puncher is a player and its HP changed
1121                 if (dst_origin_hp != playersao->getHP())
1122                         SendPlayerHPOrDie(playersao,
1123                                         PlayerHPChangeReason(PlayerHPChangeReason::PLAYER_PUNCH, pointed_object));
1124
1125                 return;
1126         } // action == INTERACT_START_DIGGING
1127
1128         case INTERACT_STOP_DIGGING:
1129                 // Nothing to do
1130                 return;
1131
1132         case INTERACT_DIGGING_COMPLETED: {
1133                 // Only digging of nodes
1134                 if (pointed.type != POINTEDTHING_NODE)
1135                         return;
1136                 bool pos_ok;
1137                 v3s16 p_under = pointed.node_undersurface;
1138                 MapNode n = m_env->getMap().getNode(p_under, &pos_ok);
1139                 if (!pos_ok) {
1140                         infostream << "Server: Not finishing digging: Node not found. "
1141                                 "Adding block to emerge queue." << std::endl;
1142                         m_emerge->enqueueBlockEmerge(peer_id,
1143                                 getNodeBlockPos(pointed.node_abovesurface), false);
1144                 }
1145
1146                 /* Cheat prevention */
1147                 bool is_valid_dig = true;
1148                 if (enable_anticheat && !isSingleplayer()) {
1149                         v3s16 nocheat_p = playersao->getNoCheatDigPos();
1150                         float nocheat_t = playersao->getNoCheatDigTime();
1151                         playersao->noCheatDigEnd();
1152                         // If player didn't start digging this, ignore dig
1153                         if (nocheat_p != p_under) {
1154                                 infostream << "Server: " << player->getName()
1155                                                 << " started digging "
1156                                                 << PP(nocheat_p) << " and completed digging "
1157                                                 << PP(p_under) << "; not digging." << std::endl;
1158                                 is_valid_dig = false;
1159                                 // Call callbacks
1160                                 m_script->on_cheat(playersao, "finished_unknown_dig");
1161                         }
1162
1163                         // Get player's wielded item
1164                         // See also: Game::handleDigging
1165                         ItemStack selected_item, hand_item;
1166                         playersao->getPlayer()->getWieldedItem(&selected_item, &hand_item);
1167
1168                         // Get diggability and expected digging time
1169                         DigParams params = getDigParams(m_nodedef->get(n).groups,
1170                                         &selected_item.getToolCapabilities(m_itemdef));
1171                         // If can't dig, try hand
1172                         if (!params.diggable) {
1173                                 params = getDigParams(m_nodedef->get(n).groups,
1174                                         &hand_item.getToolCapabilities(m_itemdef));
1175                         }
1176                         // If can't dig, ignore dig
1177                         if (!params.diggable) {
1178                                 infostream << "Server: " << player->getName()
1179                                                 << " completed digging " << PP(p_under)
1180                                                 << ", which is not diggable with tool; not digging."
1181                                                 << std::endl;
1182                                 is_valid_dig = false;
1183                                 // Call callbacks
1184                                 m_script->on_cheat(playersao, "dug_unbreakable");
1185                         }
1186                         // Check digging time
1187                         // If already invalidated, we don't have to
1188                         if (!is_valid_dig) {
1189                                 // Well not our problem then
1190                         }
1191                         // Clean and long dig
1192                         else if (params.time > 2.0 && nocheat_t * 1.2 > params.time) {
1193                                 // All is good, but grab time from pool; don't care if
1194                                 // it's actually available
1195                                 playersao->getDigPool().grab(params.time);
1196                         }
1197                         // Short or laggy dig
1198                         // Try getting the time from pool
1199                         else if (playersao->getDigPool().grab(params.time)) {
1200                                 // All is good
1201                         }
1202                         // Dig not possible
1203                         else {
1204                                 infostream << "Server: " << player->getName()
1205                                                 << " completed digging " << PP(p_under)
1206                                                 << "too fast; not digging." << std::endl;
1207                                 is_valid_dig = false;
1208                                 // Call callbacks
1209                                 m_script->on_cheat(playersao, "dug_too_fast");
1210                         }
1211                 }
1212
1213                 /* Actually dig node */
1214
1215                 if (is_valid_dig && n.getContent() != CONTENT_IGNORE)
1216                         m_script->node_on_dig(p_under, n, playersao);
1217
1218                 v3s16 blockpos = getNodeBlockPos(p_under);
1219                 RemoteClient *client = getClient(peer_id);
1220                 // Send unusual result (that is, node not being removed)
1221                 if (m_env->getMap().getNode(p_under).getContent() != CONTENT_AIR)
1222                         // Re-send block to revert change on client-side
1223                         client->SetBlockNotSent(blockpos);
1224                 else
1225                         client->ResendBlockIfOnWire(blockpos);
1226
1227                 return;
1228         } // action == INTERACT_DIGGING_COMPLETED
1229
1230         // Place block or right-click object
1231         case INTERACT_PLACE: {
1232                 ItemStack selected_item;
1233                 playersao->getWieldedItem(&selected_item, nullptr);
1234
1235                 // Reset build time counter
1236                 if (pointed.type == POINTEDTHING_NODE &&
1237                                 selected_item.getDefinition(m_itemdef).type == ITEM_NODE)
1238                         getClient(peer_id)->m_time_from_building = 0.0;
1239
1240                 if (pointed.type == POINTEDTHING_OBJECT) {
1241                         // Right click object
1242
1243                         // Skip if object can't be interacted with anymore
1244                         if (pointed_object->isGone())
1245                                 return;
1246
1247                         actionstream << player->getName() << " right-clicks object "
1248                                         << pointed.object_id << ": "
1249                                         << pointed_object->getDescription() << std::endl;
1250
1251                         // Do stuff
1252                         if (m_script->item_OnSecondaryUse(
1253                                         selected_item, playersao, pointed)) {
1254                                 if (playersao->setWieldedItem(selected_item)) {
1255                                         SendInventory(playersao, true);
1256                                 }
1257                         }
1258
1259                         pointed_object->rightClick(playersao);
1260                 } else if (m_script->item_OnPlace(selected_item, playersao, pointed)) {
1261                         // Placement was handled in lua
1262
1263                         // Apply returned ItemStack
1264                         if (playersao->setWieldedItem(selected_item))
1265                                 SendInventory(playersao, true);
1266                 }
1267
1268                 if (pointed.type != POINTEDTHING_NODE)
1269                         return;
1270
1271                 // If item has node placement prediction, always send the
1272                 // blocks to make sure the client knows what exactly happened
1273                 RemoteClient *client = getClient(peer_id);
1274                 v3s16 blockpos = getNodeBlockPos(pointed.node_abovesurface);
1275                 v3s16 blockpos2 = getNodeBlockPos(pointed.node_undersurface);
1276                 if (!selected_item.getDefinition(m_itemdef
1277                                 ).node_placement_prediction.empty()) {
1278                         client->SetBlockNotSent(blockpos);
1279                         if (blockpos2 != blockpos)
1280                                 client->SetBlockNotSent(blockpos2);
1281                 } else {
1282                         client->ResendBlockIfOnWire(blockpos);
1283                         if (blockpos2 != blockpos)
1284                                 client->ResendBlockIfOnWire(blockpos2);
1285                 }
1286
1287                 return;
1288         } // action == INTERACT_PLACE
1289
1290         case INTERACT_USE: {
1291                 ItemStack selected_item;
1292                 playersao->getWieldedItem(&selected_item, nullptr);
1293
1294                 actionstream << player->getName() << " uses " << selected_item.name
1295                                 << ", pointing at " << pointed.dump() << std::endl;
1296
1297                 if (m_script->item_OnUse(selected_item, playersao, pointed)) {
1298                         // Apply returned ItemStack
1299                         if (playersao->setWieldedItem(selected_item))
1300                                 SendInventory(playersao, true);
1301                 }
1302
1303                 return;
1304         }
1305
1306         // Rightclick air
1307         case INTERACT_ACTIVATE: {
1308                 ItemStack selected_item;
1309                 playersao->getWieldedItem(&selected_item, nullptr);
1310
1311                 actionstream << player->getName() << " activates "
1312                                 << selected_item.name << std::endl;
1313
1314                 pointed.type = POINTEDTHING_NOTHING; // can only ever be NOTHING
1315
1316                 if (m_script->item_OnSecondaryUse(selected_item, playersao, pointed)) {
1317                         if (playersao->setWieldedItem(selected_item))
1318                                 SendInventory(playersao, true);
1319                 }
1320
1321                 return;
1322         }
1323
1324         default:
1325                 warningstream << "Server: Invalid action " << action << std::endl;
1326
1327         }
1328 }
1329
1330 void Server::handleCommand_RemovedSounds(NetworkPacket* pkt)
1331 {
1332         u16 num;
1333         *pkt >> num;
1334         for (u16 k = 0; k < num; k++) {
1335                 s32 id;
1336
1337                 *pkt >> id;
1338
1339                 std::unordered_map<s32, ServerPlayingSound>::iterator i =
1340                         m_playing_sounds.find(id);
1341                 if (i == m_playing_sounds.end())
1342                         continue;
1343
1344                 ServerPlayingSound &psound = i->second;
1345                 psound.clients.erase(pkt->getPeerId());
1346                 if (psound.clients.empty())
1347                         m_playing_sounds.erase(i++);
1348         }
1349 }
1350
1351 void Server::handleCommand_NodeMetaFields(NetworkPacket* pkt)
1352 {
1353         v3s16 p;
1354         std::string formname;
1355         u16 num;
1356
1357         *pkt >> p >> formname >> num;
1358
1359         StringMap fields;
1360         for (u16 k = 0; k < num; k++) {
1361                 std::string fieldname;
1362                 *pkt >> fieldname;
1363                 fields[fieldname] = pkt->readLongString();
1364         }
1365
1366         session_t peer_id = pkt->getPeerId();
1367         RemotePlayer *player = m_env->getPlayer(peer_id);
1368
1369         if (player == NULL) {
1370                 errorstream <<
1371                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
1372                         peer_id << " disconnecting peer!" << std::endl;
1373                 DisconnectPeer(peer_id);
1374                 return;
1375         }
1376
1377         PlayerSAO *playersao = player->getPlayerSAO();
1378         if (playersao == NULL) {
1379                 errorstream <<
1380                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
1381                         peer_id << " disconnecting peer!" << std::endl;
1382                 DisconnectPeer(peer_id);
1383                 return;
1384         }
1385
1386         // If something goes wrong, this player is to blame
1387         RollbackScopeActor rollback_scope(m_rollback,
1388                         std::string("player:")+player->getName());
1389
1390         // Check the target node for rollback data; leave others unnoticed
1391         RollbackNode rn_old(&m_env->getMap(), p, this);
1392
1393         m_script->node_on_receive_fields(p, formname, fields, playersao);
1394
1395         // Report rollback data
1396         RollbackNode rn_new(&m_env->getMap(), p, this);
1397         if (rollback() && rn_new != rn_old) {
1398                 RollbackAction action;
1399                 action.setSetNode(p, rn_old, rn_new);
1400                 rollback()->reportAction(action);
1401         }
1402 }
1403
1404 void Server::handleCommand_InventoryFields(NetworkPacket* pkt)
1405 {
1406         std::string client_formspec_name;
1407         u16 num;
1408
1409         *pkt >> client_formspec_name >> num;
1410
1411         StringMap fields;
1412         for (u16 k = 0; k < num; k++) {
1413                 std::string fieldname;
1414                 *pkt >> fieldname;
1415                 fields[fieldname] = pkt->readLongString();
1416         }
1417
1418         session_t peer_id = pkt->getPeerId();
1419         RemotePlayer *player = m_env->getPlayer(peer_id);
1420
1421         if (player == NULL) {
1422                 errorstream <<
1423                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
1424                         peer_id << " disconnecting peer!" << std::endl;
1425                 DisconnectPeer(peer_id);
1426                 return;
1427         }
1428
1429         PlayerSAO *playersao = player->getPlayerSAO();
1430         if (playersao == NULL) {
1431                 errorstream <<
1432                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
1433                         peer_id << " disconnecting peer!" << std::endl;
1434                 DisconnectPeer(peer_id);
1435                 return;
1436         }
1437
1438         if (client_formspec_name.empty()) { // pass through inventory submits
1439                 m_script->on_playerReceiveFields(playersao, client_formspec_name, fields);
1440                 return;
1441         }
1442
1443         // verify that we displayed the formspec to the user
1444         const auto peer_state_iterator = m_formspec_state_data.find(peer_id);
1445         if (peer_state_iterator != m_formspec_state_data.end()) {
1446                 const std::string &server_formspec_name = peer_state_iterator->second;
1447                 if (client_formspec_name == server_formspec_name) {
1448                         auto it = fields.find("quit");
1449                         if (it != fields.end() && it->second == "true")
1450                                 m_formspec_state_data.erase(peer_state_iterator);
1451
1452                         m_script->on_playerReceiveFields(playersao, client_formspec_name, fields);
1453                         return;
1454                 }
1455                 actionstream << "'" << player->getName()
1456                         << "' submitted formspec ('" << client_formspec_name
1457                         << "') but the name of the formspec doesn't match the"
1458                         " expected name ('" << server_formspec_name << "')";
1459
1460         } else {
1461                 actionstream << "'" << player->getName()
1462                         << "' submitted formspec ('" << client_formspec_name
1463                         << "') but server hasn't sent formspec to client";
1464         }
1465         actionstream << ", possible exploitation attempt" << std::endl;
1466 }
1467
1468 void Server::handleCommand_FirstSrp(NetworkPacket* pkt)
1469 {
1470         session_t peer_id = pkt->getPeerId();
1471         RemoteClient *client = getClient(peer_id, CS_Invalid);
1472         ClientState cstate = client->getState();
1473
1474         std::string playername = client->getName();
1475
1476         std::string salt;
1477         std::string verification_key;
1478
1479         std::string addr_s = getPeerAddress(peer_id).serializeString();
1480         u8 is_empty;
1481
1482         *pkt >> salt >> verification_key >> is_empty;
1483
1484         verbosestream << "Server: Got TOSERVER_FIRST_SRP from " << addr_s
1485                 << ", with is_empty=" << (is_empty == 1) << std::endl;
1486
1487         // Either this packet is sent because the user is new or to change the password
1488         if (cstate == CS_HelloSent) {
1489                 if (!client->isMechAllowed(AUTH_MECHANISM_FIRST_SRP)) {
1490                         actionstream << "Server: Client from " << addr_s
1491                                         << " tried to set password without being "
1492                                         << "authenticated, or the username being new." << std::endl;
1493                         DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1494                         return;
1495                 }
1496
1497                 if (!isSingleplayer() &&
1498                                 g_settings->getBool("disallow_empty_password") &&
1499                                 is_empty == 1) {
1500                         actionstream << "Server: " << playername
1501                                         << " supplied empty password from " << addr_s << std::endl;
1502                         DenyAccess(peer_id, SERVER_ACCESSDENIED_EMPTY_PASSWORD);
1503                         return;
1504                 }
1505
1506                 std::string initial_ver_key;
1507
1508                 initial_ver_key = encode_srp_verifier(verification_key, salt);
1509                 m_script->createAuth(playername, initial_ver_key);
1510                 m_script->on_authplayer(playername, addr_s, true);
1511
1512                 acceptAuth(peer_id, false);
1513         } else {
1514                 if (cstate < CS_SudoMode) {
1515                         infostream << "Server::ProcessData(): Ignoring TOSERVER_FIRST_SRP from "
1516                                         << addr_s << ": " << "Client has wrong state " << cstate << "."
1517                                         << std::endl;
1518                         return;
1519                 }
1520                 m_clients.event(peer_id, CSE_SudoLeave);
1521                 std::string pw_db_field = encode_srp_verifier(verification_key, salt);
1522                 bool success = m_script->setPassword(playername, pw_db_field);
1523                 if (success) {
1524                         actionstream << playername << " changes password" << std::endl;
1525                         SendChatMessage(peer_id, ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
1526                                 L"Password change successful."));
1527                 } else {
1528                         actionstream << playername <<
1529                                 " tries to change password but it fails" << std::endl;
1530                         SendChatMessage(peer_id, ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
1531                                 L"Password change failed or unavailable."));
1532                 }
1533         }
1534 }
1535
1536 void Server::handleCommand_SrpBytesA(NetworkPacket* pkt)
1537 {
1538         session_t peer_id = pkt->getPeerId();
1539         RemoteClient *client = getClient(peer_id, CS_Invalid);
1540         ClientState cstate = client->getState();
1541
1542         bool wantSudo = (cstate == CS_Active);
1543
1544         if (!((cstate == CS_HelloSent) || (cstate == CS_Active))) {
1545                 actionstream << "Server: got SRP _A packet in wrong state " << cstate <<
1546                         " from " << getPeerAddress(peer_id).serializeString() <<
1547                         ". Ignoring." << std::endl;
1548                 return;
1549         }
1550
1551         if (client->chosen_mech != AUTH_MECHANISM_NONE) {
1552                 actionstream << "Server: got SRP _A packet, while auth is already "
1553                         "going on with mech " << client->chosen_mech << " from " <<
1554                         getPeerAddress(peer_id).serializeString() <<
1555                         " (wantSudo=" << wantSudo << "). Ignoring." << std::endl;
1556                 if (wantSudo) {
1557                         DenySudoAccess(peer_id);
1558                         return;
1559                 }
1560
1561                 DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1562                 return;
1563         }
1564
1565         std::string bytes_A;
1566         u8 based_on;
1567         *pkt >> bytes_A >> based_on;
1568
1569         infostream << "Server: TOSERVER_SRP_BYTES_A received with "
1570                 << "based_on=" << int(based_on) << " and len_A="
1571                 << bytes_A.length() << "." << std::endl;
1572
1573         AuthMechanism chosen = (based_on == 0) ?
1574                 AUTH_MECHANISM_LEGACY_PASSWORD : AUTH_MECHANISM_SRP;
1575
1576         if (wantSudo) {
1577                 if (!client->isSudoMechAllowed(chosen)) {
1578                         actionstream << "Server: Player \"" << client->getName() <<
1579                                 "\" at " << getPeerAddress(peer_id).serializeString() <<
1580                                 " tried to change password using unallowed mech " << chosen <<
1581                                 "." << std::endl;
1582                         DenySudoAccess(peer_id);
1583                         return;
1584                 }
1585         } else {
1586                 if (!client->isMechAllowed(chosen)) {
1587                         actionstream << "Server: Client tried to authenticate from " <<
1588                                 getPeerAddress(peer_id).serializeString() <<
1589                                 " using unallowed mech " << chosen << "." << std::endl;
1590                         DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1591                         return;
1592                 }
1593         }
1594
1595         client->chosen_mech = chosen;
1596
1597         std::string salt;
1598         std::string verifier;
1599
1600         if (based_on == 0) {
1601
1602                 generate_srp_verifier_and_salt(client->getName(), client->enc_pwd,
1603                         &verifier, &salt);
1604         } else if (!decode_srp_verifier_and_salt(client->enc_pwd, &verifier, &salt)) {
1605                 // Non-base64 errors should have been catched in the init handler
1606                 actionstream << "Server: User " << client->getName() <<
1607                         " tried to log in, but srp verifier field was invalid (most likely "
1608                         "invalid base64)." << std::endl;
1609                 DenyAccess(peer_id, SERVER_ACCESSDENIED_SERVER_FAIL);
1610                 return;
1611         }
1612
1613         char *bytes_B = 0;
1614         size_t len_B = 0;
1615
1616         client->auth_data = srp_verifier_new(SRP_SHA256, SRP_NG_2048,
1617                 client->getName().c_str(),
1618                 (const unsigned char *) salt.c_str(), salt.size(),
1619                 (const unsigned char *) verifier.c_str(), verifier.size(),
1620                 (const unsigned char *) bytes_A.c_str(), bytes_A.size(),
1621                 NULL, 0,
1622                 (unsigned char **) &bytes_B, &len_B, NULL, NULL);
1623
1624         if (!bytes_B) {
1625                 actionstream << "Server: User " << client->getName()
1626                         << " tried to log in, SRP-6a safety check violated in _A handler."
1627                         << std::endl;
1628                 if (wantSudo) {
1629                         DenySudoAccess(peer_id);
1630                         return;
1631                 }
1632
1633                 DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1634                 return;
1635         }
1636
1637         NetworkPacket resp_pkt(TOCLIENT_SRP_BYTES_S_B, 0, peer_id);
1638         resp_pkt << salt << std::string(bytes_B, len_B);
1639         Send(&resp_pkt);
1640 }
1641
1642 void Server::handleCommand_SrpBytesM(NetworkPacket* pkt)
1643 {
1644         session_t peer_id = pkt->getPeerId();
1645         RemoteClient *client = getClient(peer_id, CS_Invalid);
1646         ClientState cstate = client->getState();
1647         std::string addr_s = getPeerAddress(pkt->getPeerId()).serializeString();
1648         std::string playername = client->getName();
1649
1650         bool wantSudo = (cstate == CS_Active);
1651
1652         verbosestream << "Server: Received TOSERVER_SRP_BYTES_M." << std::endl;
1653
1654         if (!((cstate == CS_HelloSent) || (cstate == CS_Active))) {
1655                 warningstream << "Server: got SRP_M packet in wrong state "
1656                         << cstate << " from " << addr_s << ". Ignoring." << std::endl;
1657                 return;
1658         }
1659
1660         if (client->chosen_mech != AUTH_MECHANISM_SRP &&
1661                         client->chosen_mech != AUTH_MECHANISM_LEGACY_PASSWORD) {
1662                 warningstream << "Server: got SRP_M packet, while auth "
1663                         "is going on with mech " << client->chosen_mech << " from "
1664                         << addr_s << " (wantSudo=" << wantSudo << "). Denying." << std::endl;
1665                 if (wantSudo) {
1666                         DenySudoAccess(peer_id);
1667                         return;
1668                 }
1669
1670                 DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1671                 return;
1672         }
1673
1674         std::string bytes_M;
1675         *pkt >> bytes_M;
1676
1677         if (srp_verifier_get_session_key_length((SRPVerifier *) client->auth_data)
1678                         != bytes_M.size()) {
1679                 actionstream << "Server: User " << playername << " at " << addr_s
1680                         << " sent bytes_M with invalid length " << bytes_M.size() << std::endl;
1681                 DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1682                 return;
1683         }
1684
1685         unsigned char *bytes_HAMK = 0;
1686
1687         srp_verifier_verify_session((SRPVerifier *) client->auth_data,
1688                 (unsigned char *)bytes_M.c_str(), &bytes_HAMK);
1689
1690         if (!bytes_HAMK) {
1691                 if (wantSudo) {
1692                         actionstream << "Server: User " << playername << " at " << addr_s
1693                                 << " tried to change their password, but supplied wrong"
1694                                 << " (SRP) password for authentication." << std::endl;
1695                         DenySudoAccess(peer_id);
1696                         return;
1697                 }
1698
1699                 actionstream << "Server: User " << playername << " at " << addr_s
1700                         << " supplied wrong password (auth mechanism: SRP)." << std::endl;
1701                 m_script->on_authplayer(playername, addr_s, false);
1702                 DenyAccess(peer_id, SERVER_ACCESSDENIED_WRONG_PASSWORD);
1703                 return;
1704         }
1705
1706         if (client->create_player_on_auth_success) {
1707                 m_script->createAuth(playername, client->enc_pwd);
1708
1709                 std::string checkpwd; // not used, but needed for passing something
1710                 if (!m_script->getAuth(playername, &checkpwd, NULL)) {
1711                         errorstream << "Server: " << playername <<
1712                                 " cannot be authenticated (auth handler does not work?)" <<
1713                                 std::endl;
1714                         DenyAccess(peer_id, SERVER_ACCESSDENIED_SERVER_FAIL);
1715                         return;
1716                 }
1717                 client->create_player_on_auth_success = false;
1718         }
1719
1720         m_script->on_authplayer(playername, addr_s, true);
1721         acceptAuth(peer_id, wantSudo);
1722 }
1723
1724 /*
1725  * Mod channels
1726  */
1727
1728 void Server::handleCommand_ModChannelJoin(NetworkPacket *pkt)
1729 {
1730         std::string channel_name;
1731         *pkt >> channel_name;
1732
1733         session_t peer_id = pkt->getPeerId();
1734         NetworkPacket resp_pkt(TOCLIENT_MODCHANNEL_SIGNAL,
1735                 1 + 2 + channel_name.size(), peer_id);
1736
1737         // Send signal to client to notify join succeed or not
1738         if (g_settings->getBool("enable_mod_channels") &&
1739                         m_modchannel_mgr->joinChannel(channel_name, peer_id)) {
1740                 resp_pkt << (u8) MODCHANNEL_SIGNAL_JOIN_OK;
1741                 infostream << "Peer " << peer_id << " joined channel " <<
1742                         channel_name << std::endl;
1743         }
1744         else {
1745                 resp_pkt << (u8)MODCHANNEL_SIGNAL_JOIN_FAILURE;
1746                 infostream << "Peer " << peer_id << " tried to join channel " <<
1747                         channel_name << ", but was already registered." << std::endl;
1748         }
1749         resp_pkt << channel_name;
1750         Send(&resp_pkt);
1751 }
1752
1753 void Server::handleCommand_ModChannelLeave(NetworkPacket *pkt)
1754 {
1755         std::string channel_name;
1756         *pkt >> channel_name;
1757
1758         session_t peer_id = pkt->getPeerId();
1759         NetworkPacket resp_pkt(TOCLIENT_MODCHANNEL_SIGNAL,
1760                 1 + 2 + channel_name.size(), peer_id);
1761
1762         // Send signal to client to notify join succeed or not
1763         if (g_settings->getBool("enable_mod_channels") &&
1764                         m_modchannel_mgr->leaveChannel(channel_name, peer_id)) {
1765                 resp_pkt << (u8)MODCHANNEL_SIGNAL_LEAVE_OK;
1766                 infostream << "Peer " << peer_id << " left channel " << channel_name <<
1767                         std::endl;
1768         } else {
1769                 resp_pkt << (u8) MODCHANNEL_SIGNAL_LEAVE_FAILURE;
1770                 infostream << "Peer " << peer_id << " left channel " << channel_name <<
1771                         ", but was not registered." << std::endl;
1772         }
1773         resp_pkt << channel_name;
1774         Send(&resp_pkt);
1775 }
1776
1777 void Server::handleCommand_ModChannelMsg(NetworkPacket *pkt)
1778 {
1779         std::string channel_name, channel_msg;
1780         *pkt >> channel_name >> channel_msg;
1781
1782         session_t peer_id = pkt->getPeerId();
1783         verbosestream << "Mod channel message received from peer " << peer_id <<
1784                 " on channel " << channel_name << " message: " << channel_msg <<
1785                 std::endl;
1786
1787         // If mod channels are not enabled, discard message
1788         if (!g_settings->getBool("enable_mod_channels")) {
1789                 return;
1790         }
1791
1792         // If channel not registered, signal it and ignore message
1793         if (!m_modchannel_mgr->channelRegistered(channel_name)) {
1794                 NetworkPacket resp_pkt(TOCLIENT_MODCHANNEL_SIGNAL,
1795                         1 + 2 + channel_name.size(), peer_id);
1796                 resp_pkt << (u8)MODCHANNEL_SIGNAL_CHANNEL_NOT_REGISTERED << channel_name;
1797                 Send(&resp_pkt);
1798                 return;
1799         }
1800
1801         // @TODO: filter, rate limit
1802
1803         broadcastModChannelMessage(channel_name, channel_msg, peer_id);
1804 }