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         std::string addr_s;
  60         try {
  61                 Address address = getPeerAddress(peer_id);
  62                 addr_s = address.serializeString();
  63         }
  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 net_proto_version is set, this client has already been handled
  77         if (client->getState() > CS_Created) {
  78                 verbosestream << "Server: Ignoring multiple TOSERVER_INITs from " <<
  79                         addr_s << " (peer_id=" << peer_id << ")" << std::endl;
  80                 return;
  81         }
  82
  83         verbosestream << "Server: Got TOSERVER_INIT from " << addr_s <<
  84                 " (peer_id=" << peer_id << ")" << std::endl;
  85
  86         // Do not allow multiple players in simple singleplayer mode.
  87         // This isn't a perfect way to do it, but will suffice for now
  88         if (m_simple_singleplayer_mode && m_clients.getClientIDs().size() > 1) {
  89                 infostream << "Server: Not allowing another client (" << addr_s <<
  90                         ") to connect in simple singleplayer mode" << std::endl;
  91                 DenyAccess(peer_id, SERVER_ACCESSDENIED_SINGLEPLAYER);
  92                 return;
  93         }
  94
  95         // First byte after command is maximum supported
  96         // serialization version
  97         u8 client_max;
  98         u16 supp_compr_modes;
  99         u16 min_net_proto_version = 0;
 100         u16 max_net_proto_version;
 101         std::string playerName;
 102
 103         *pkt >> client_max >> supp_compr_modes >> min_net_proto_version
 104                         >> max_net_proto_version >> playerName;
 105
 106         u8 our_max = SER_FMT_VER_HIGHEST_READ;
 107         // Use the highest version supported by both
 108         u8 depl_serial_v = std::min(client_max, our_max);
 109         // If it's lower than the lowest supported, give up.
 110         if (depl_serial_v < SER_FMT_VER_LOWEST_READ)
 111                 depl_serial_v = SER_FMT_VER_INVALID;
 112
 113         if (depl_serial_v == SER_FMT_VER_INVALID) {
 114                 actionstream << "Server: A mismatched client tried to connect from " <<
 115                         addr_s << " ser_fmt_max=" << (int)client_max << std::endl;
 116                 DenyAccess(peer_id, SERVER_ACCESSDENIED_WRONG_VERSION);
 117                 return;
 118         }
 119
 120         client->setPendingSerializationVersion(depl_serial_v);
 121
 122         /*
 123                 Read and check network protocol version
 124         */
 125
 126         u16 net_proto_version = 0;
 127
 128         // Figure out a working version if it is possible at all
 129         if (max_net_proto_version >= SERVER_PROTOCOL_VERSION_MIN ||
 130                         min_net_proto_version <= SERVER_PROTOCOL_VERSION_MAX) {
 131                 // If maximum is larger than our maximum, go with our maximum
 132                 if (max_net_proto_version > SERVER_PROTOCOL_VERSION_MAX)
 133                         net_proto_version = SERVER_PROTOCOL_VERSION_MAX;
 134                 // Else go with client's maximum
 135                 else
 136                         net_proto_version = max_net_proto_version;
 137         }
 138
 139         verbosestream << "Server: " << addr_s << ": Protocol version: min: "
 140                         << min_net_proto_version << ", max: " << max_net_proto_version
 141                         << ", chosen: " << net_proto_version << std::endl;
 142
 143         client->net_proto_version = net_proto_version;
 144
 145         if ((g_settings->getBool("strict_protocol_version_checking") &&
 146                         net_proto_version != LATEST_PROTOCOL_VERSION) ||
 147                         net_proto_version < SERVER_PROTOCOL_VERSION_MIN ||
 148                         net_proto_version > SERVER_PROTOCOL_VERSION_MAX) {
 149                 actionstream << "Server: A mismatched client tried to connect from " <<
 150                         addr_s << " proto_max=" << (int)max_net_proto_version << std::endl;
 151                 DenyAccess(peer_id, SERVER_ACCESSDENIED_WRONG_VERSION);
 152                 return;
 153         }
 154
 155         /*
 156                 Validate player name
 157         */
 158         const char* playername = playerName.c_str();
 159
 160         size_t pns = playerName.size();
 161         if (pns == 0 || pns > PLAYERNAME_SIZE) {
 162                 actionstream << "Server: Player with " <<
 163                         ((pns > PLAYERNAME_SIZE) ? "a too long" : "an empty") <<
 164                         " name tried to connect from " << addr_s << std::endl;
 165                 DenyAccess(peer_id, SERVER_ACCESSDENIED_WRONG_NAME);
 166                 return;
 167         }
 168
 169         if (!string_allowed(playerName, PLAYERNAME_ALLOWED_CHARS)) {
 170                 actionstream << "Server: Player with an invalid name tried to connect "
 171                         "from " << addr_s << std::endl;
 172                 DenyAccess(peer_id, SERVER_ACCESSDENIED_WRONG_CHARS_IN_NAME);
 173                 return;
 174         }
 175
 176         m_clients.setPlayerName(peer_id, playername);
 177         //TODO (later) case insensitivity
 178
 179         std::string legacyPlayerNameCasing = playerName;
 180
 181         if (!isSingleplayer() && strcasecmp(playername, "singleplayer") == 0) {
 182                 actionstream << "Server: Player with the name \"singleplayer\" tried "
 183                         "to connect from " << addr_s << std::endl;
 184                 DenyAccess(peer_id, SERVER_ACCESSDENIED_WRONG_NAME);
 185                 return;
 186         }
 187
 188         {
 189                 std::string reason;
 190                 if (m_script->on_prejoinplayer(playername, addr_s, &reason)) {
 191                         actionstream << "Server: Player with the name \"" << playerName <<
 192                                 "\" tried to connect from " << addr_s <<
 193                                 " but it was disallowed for the following reason: " << reason <<
 194                                 std::endl;
 195                         DenyAccess(peer_id, SERVER_ACCESSDENIED_CUSTOM_STRING, reason);
 196                         return;
 197                 }
 198         }
 199
 200         infostream << "Server: New connection: \"" << playerName << "\" from " <<
 201                 addr_s << " (peer_id=" << peer_id << ")" << std::endl;
 202
 203         // Enforce user limit.
 204         // Don't enforce for users that have some admin right or mod permits it.
 205         if (m_clients.isUserLimitReached() &&
 206                         playername != g_settings->get("name") &&
 207                         !m_script->can_bypass_userlimit(playername, addr_s)) {
 208                 actionstream << "Server: " << playername << " tried to join from " <<
 209                         addr_s << ", but there are already max_users=" <<
 210                         g_settings->getU16("max_users") << " players." << std::endl;
 211                 DenyAccess(peer_id, SERVER_ACCESSDENIED_TOO_MANY_USERS);
 212                 return;
 213         }
 214
 215         /*
 216                 Compose auth methods for answer
 217         */
 218         std::string encpwd; // encrypted Password field for the user
 219         bool has_auth = m_script->getAuth(playername, &encpwd, NULL);
 220         u32 auth_mechs = 0;
 221
 222         client->chosen_mech = AUTH_MECHANISM_NONE;
 223
 224         if (has_auth) {
 225                 std::vector<std::string> pwd_components = str_split(encpwd, '#');
 226                 if (pwd_components.size() == 4) {
 227                         if (pwd_components[1] == "1") { // 1 means srp
 228                                 auth_mechs |= AUTH_MECHANISM_SRP;
 229                                 client->enc_pwd = encpwd;
 230                         } else {
 231                                 actionstream << "User " << playername << " tried to log in, "
 232                                         "but password field was invalid (unknown mechcode)." <<
 233                                         std::endl;
 234                                 DenyAccess(peer_id, SERVER_ACCESSDENIED_SERVER_FAIL);
 235                                 return;
 236                         }
 237                 } else if (base64_is_valid(encpwd)) {
 238                         auth_mechs |= AUTH_MECHANISM_LEGACY_PASSWORD;
 239                         client->enc_pwd = encpwd;
 240                 } else {
 241                         actionstream << "User " << playername << " tried to log in, but "
 242                                 "password field was invalid (invalid base64)." << std::endl;
 243                         DenyAccess(peer_id, SERVER_ACCESSDENIED_SERVER_FAIL);
 244                         return;
 245                 }
 246         } else {
 247                 std::string default_password = g_settings->get("default_password");
 248                 if (default_password.length() == 0) {
 249                         auth_mechs |= AUTH_MECHANISM_FIRST_SRP;
 250                 } else {
 251                         // Take care of default passwords.
 252                         client->enc_pwd = get_encoded_srp_verifier(playerName, default_password);
 253                         auth_mechs |= AUTH_MECHANISM_SRP;
 254                         // Allocate player in db, but only on successful login.
 255                         client->create_player_on_auth_success = true;
 256                 }
 257         }
 258
 259         /*
 260                 Answer with a TOCLIENT_HELLO
 261         */
 262
 263         verbosestream << "Sending TOCLIENT_HELLO with auth method field: "
 264                 << auth_mechs << std::endl;
 265
 266         NetworkPacket resp_pkt(TOCLIENT_HELLO,
 267                 1 + 4 + legacyPlayerNameCasing.size(), peer_id);
 268
 269         u16 depl_compress_mode = NETPROTO_COMPRESSION_NONE;
 270         resp_pkt << depl_serial_v << depl_compress_mode << net_proto_version
 271                 << auth_mechs << legacyPlayerNameCasing;
 272
 273         Send(&resp_pkt);
 274
 275         client->allowed_auth_mechs = auth_mechs;
 276         client->setDeployedCompressionMode(depl_compress_mode);
 277
 278         m_clients.event(peer_id, CSE_Hello);
 279 }
 280
 281 void Server::handleCommand_Init2(NetworkPacket* pkt)
 282 {
 283         session_t peer_id = pkt->getPeerId();
 284         verbosestream << "Server: Got TOSERVER_INIT2 from " << peer_id << std::endl;
 285
 286         m_clients.event(peer_id, CSE_GotInit2);
 287         u16 protocol_version = m_clients.getProtocolVersion(peer_id);
 288
 289         std::string lang;
 290         if (pkt->getSize() > 0)
 291                 *pkt >> lang;
 292
 293         /*
 294                 Send some initialization data
 295         */
 296
 297         infostream << "Server: Sending content to " << getPlayerName(peer_id) <<
 298                 std::endl;
 299
 300         // Send item definitions
 301         SendItemDef(peer_id, m_itemdef, protocol_version);
 302
 303         // Send node definitions
 304         SendNodeDef(peer_id, m_nodedef, protocol_version);
 305
 306         m_clients.event(peer_id, CSE_SetDefinitionsSent);
 307
 308         // Send media announcement
 309         sendMediaAnnouncement(peer_id, lang);
 310
 311         RemoteClient *client = getClient(peer_id, CS_InitDone);
 312
 313         // Keep client language for server translations
 314         client->setLangCode(lang);
 315
 316         // Send active objects
 317         {
 318                 PlayerSAO *sao = getPlayerSAO(peer_id);
 319                 if (client && sao)
 320                         SendActiveObjectRemoveAdd(client, sao);
 321         }
 322
 323         // Send detached inventories
 324         sendDetachedInventories(peer_id, false);
 325
 326         // Send player movement settings
 327         SendMovement(peer_id);
 328
 329         // Send time of day
 330         u16 time = m_env->getTimeOfDay();
 331         float time_speed = g_settings->getFloat("time_speed");
 332         SendTimeOfDay(peer_id, time, time_speed);
 333
 334         SendCSMRestrictionFlags(peer_id);
 335
 336         // Warnings about protocol version can be issued here
 337         if (client->net_proto_version < LATEST_PROTOCOL_VERSION) {
 338                 SendChatMessage(peer_id, ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
 339                         L"# Server: WARNING: YOUR CLIENT'S VERSION MAY NOT BE FULLY COMPATIBLE "
 340                         L"WITH THIS SERVER!"));
 341         }
 342 }
 343
 344 void Server::handleCommand_RequestMedia(NetworkPacket* pkt)
 345 {
 346         std::vector<std::string> tosend;
 347         u16 numfiles;
 348
 349         *pkt >> numfiles;
 350
 351         session_t peer_id = pkt->getPeerId();
 352         infostream << "Sending " << numfiles << " files to " <<
 353                 getPlayerName(peer_id) << std::endl;
 354         verbosestream << "TOSERVER_REQUEST_MEDIA: " << std::endl;
 355
 356         for (u16 i = 0; i < numfiles; i++) {
 357                 std::string name;
 358
 359                 *pkt >> name;
 360
 361                 tosend.push_back(name);
 362                 verbosestream << "TOSERVER_REQUEST_MEDIA: requested file "
 363                                 << name << std::endl;
 364         }
 365
 366         sendRequestedMedia(peer_id, tosend);
 367 }
 368
 369 void Server::handleCommand_ClientReady(NetworkPacket* pkt)
 370 {
 371         session_t peer_id = pkt->getPeerId();
 372
 373         PlayerSAO* playersao = StageTwoClientInit(peer_id);
 374
 375         if (playersao == NULL) {
 376                 errorstream << "TOSERVER_CLIENT_READY stage 2 client init failed "
 377                         "peer_id=" << peer_id << std::endl;
 378                 DisconnectPeer(peer_id);
 379                 return;
 380         }
 381
 382
 383         if (pkt->getSize() < 8) {
 384                 errorstream << "TOSERVER_CLIENT_READY client sent inconsistent data, "
 385                         "disconnecting peer_id: " << peer_id << std::endl;
 386                 DisconnectPeer(peer_id);
 387                 return;
 388         }
 389
 390         u8 major_ver, minor_ver, patch_ver, reserved;
 391         std::string full_ver;
 392         *pkt >> major_ver >> minor_ver >> patch_ver >> reserved >> full_ver;
 393
 394         m_clients.setClientVersion(peer_id, major_ver, minor_ver, patch_ver,
 395                 full_ver);
 396
 397         if (pkt->getRemainingBytes() >= 2)
 398                 *pkt >> playersao->getPlayer()->formspec_version;
 399
 400         const std::vector<std::string> &players = m_clients.getPlayerNames();
 401         NetworkPacket list_pkt(TOCLIENT_UPDATE_PLAYER_LIST, 0, peer_id);
 402         list_pkt << (u8) PLAYER_LIST_INIT << (u16) players.size();
 403         for (const std::string &player: players) {
 404                 list_pkt <<  player;
 405         }
 406         m_clients.send(peer_id, 0, &list_pkt, true);
 407
 408         NetworkPacket notice_pkt(TOCLIENT_UPDATE_PLAYER_LIST, 0, PEER_ID_INEXISTENT);
 409         // (u16) 1 + std::string represents a pseudo vector serialization representation
 410         notice_pkt << (u8) PLAYER_LIST_ADD << (u16) 1 << std::string(playersao->getPlayer()->getName());
 411         m_clients.sendToAll(&notice_pkt);
 412         m_clients.event(peer_id, CSE_SetClientReady);
 413
 414         s64 last_login;
 415         m_script->getAuth(playersao->getPlayer()->getName(), nullptr, nullptr, &last_login);
 416         m_script->on_joinplayer(playersao, last_login);
 417
 418         // Send shutdown timer if shutdown has been scheduled
 419         if (m_shutdown_state.isTimerRunning()) {
 420                 SendChatMessage(peer_id, m_shutdown_state.getShutdownTimerMessage());
 421         }
 422 }
 423
 424 void Server::handleCommand_GotBlocks(NetworkPacket* pkt)
 425 {
 426         if (pkt->getSize() < 1)
 427                 return;
 428
 429         /*
 430                 [0] u16 command
 431                 [2] u8 count
 432                 [3] v3s16 pos_0
 433                 [3+6] v3s16 pos_1
 434                 ...
 435         */
 436
 437         u8 count;
 438         *pkt >> count;
 439
 440         RemoteClient *client = getClient(pkt->getPeerId());
 441
 442         if ((s16)pkt->getSize() < 1 + (int)count * 6) {
 443                 throw con::InvalidIncomingDataException
 444                                 ("GOTBLOCKS length is too short");
 445         }
 446
 447         for (u16 i = 0; i < count; i++) {
 448                 v3s16 p;
 449                 *pkt >> p;
 450                 client->GotBlock(p);
 451         }
 452 }
 453
 454 void Server::process_PlayerPos(RemotePlayer *player, PlayerSAO *playersao,
 455         NetworkPacket *pkt)
 456 {
 457         if (pkt->getRemainingBytes() < 12 + 12 + 4 + 4 + 4 + 1 + 1)
 458                 return;
 459
 460         v3s32 ps, ss;
 461         s32 f32pitch, f32yaw;
 462         u8 f32fov;
 463
 464         *pkt >> ps;
 465         *pkt >> ss;
 466         *pkt >> f32pitch;
 467         *pkt >> f32yaw;
 468
 469         f32 pitch = (f32)f32pitch / 100.0f;
 470         f32 yaw = (f32)f32yaw / 100.0f;
 471         u32 keyPressed = 0;
 472
 473         // default behavior (in case an old client doesn't send these)
 474         f32 fov = 0;
 475         u8 wanted_range = 0;
 476
 477         *pkt >> keyPressed;
 478         *pkt >> f32fov;
 479         fov = (f32)f32fov / 80.0f;
 480         *pkt >> wanted_range;
 481
 482         v3f position((f32)ps.X / 100.0f, (f32)ps.Y / 100.0f, (f32)ps.Z / 100.0f);
 483         v3f speed((f32)ss.X / 100.0f, (f32)ss.Y / 100.0f, (f32)ss.Z / 100.0f);
 484
 485         pitch = modulo360f(pitch);
 486         yaw = wrapDegrees_0_360(yaw);
 487
 488         playersao->setBasePosition(position);
 489         player->setSpeed(speed);
 490         playersao->setLookPitch(pitch);
 491         playersao->setPlayerYaw(yaw);
 492         playersao->setFov(fov);
 493         playersao->setWantedRange(wanted_range);
 494         player->keyPressed = keyPressed;
 495         player->control.up = (keyPressed & 1);
 496         player->control.down = (keyPressed & 2);
 497         player->control.left = (keyPressed & 4);
 498         player->control.right = (keyPressed & 8);
 499         player->control.jump = (keyPressed & 16);
 500         player->control.aux1 = (keyPressed & 32);
 501         player->control.sneak = (keyPressed & 64);
 502         player->control.LMB = (keyPressed & 128);
 503         player->control.RMB = (keyPressed & 256);
 504
 505         if (playersao->checkMovementCheat()) {
 506                 // Call callbacks
 507                 m_script->on_cheat(playersao, "moved_too_fast");
 508                 SendMovePlayer(pkt->getPeerId());
 509         }
 510 }
 511
 512 void Server::handleCommand_PlayerPos(NetworkPacket* pkt)
 513 {
 514         session_t peer_id = pkt->getPeerId();
 515         RemotePlayer *player = m_env->getPlayer(peer_id);
 516         if (player == NULL) {
 517                 errorstream <<
 518                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 519                         peer_id << " disconnecting peer!" << std::endl;
 520                 DisconnectPeer(peer_id);
 521                 return;
 522         }
 523
 524         PlayerSAO *playersao = player->getPlayerSAO();
 525         if (playersao == NULL) {
 526                 errorstream <<
 527                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
 528                         peer_id << " disconnecting peer!" << std::endl;
 529                 DisconnectPeer(peer_id);
 530                 return;
 531         }
 532
 533         // If player is dead we don't care of this packet
 534         if (playersao->isDead()) {
 535                 verbosestream << "TOSERVER_PLAYERPOS: " << player->getName()
 536                                 << " is dead. Ignoring packet";
 537                 return;
 538         }
 539
 540         process_PlayerPos(player, playersao, pkt);
 541 }
 542
 543 void Server::handleCommand_DeletedBlocks(NetworkPacket* pkt)
 544 {
 545         if (pkt->getSize() < 1)
 546                 return;
 547
 548         /*
 549                 [0] u16 command
 550                 [2] u8 count
 551                 [3] v3s16 pos_0
 552                 [3+6] v3s16 pos_1
 553                 ...
 554         */
 555
 556         u8 count;
 557         *pkt >> count;
 558
 559         RemoteClient *client = getClient(pkt->getPeerId());
 560
 561         if ((s16)pkt->getSize() < 1 + (int)count * 6) {
 562                 throw con::InvalidIncomingDataException
 563                                 ("DELETEDBLOCKS length is too short");
 564         }
 565
 566         for (u16 i = 0; i < count; i++) {
 567                 v3s16 p;
 568                 *pkt >> p;
 569                 client->SetBlockNotSent(p);
 570         }
 571 }
 572
 573 void Server::handleCommand_InventoryAction(NetworkPacket* pkt)
 574 {
 575         session_t peer_id = pkt->getPeerId();
 576         RemotePlayer *player = m_env->getPlayer(peer_id);
 577
 578         if (player == NULL) {
 579                 errorstream <<
 580                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 581                         peer_id << " disconnecting peer!" << std::endl;
 582                 DisconnectPeer(peer_id);
 583                 return;
 584         }
 585
 586         PlayerSAO *playersao = player->getPlayerSAO();
 587         if (playersao == NULL) {
 588                 errorstream <<
 589                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
 590                         peer_id << " disconnecting peer!" << std::endl;
 591                 DisconnectPeer(peer_id);
 592                 return;
 593         }
 594
 595         // Strip command and create a stream
 596         std::string datastring(pkt->getString(0), pkt->getSize());
 597         verbosestream << "TOSERVER_INVENTORY_ACTION: data=" << datastring
 598                 << std::endl;
 599         std::istringstream is(datastring, std::ios_base::binary);
 600         // Create an action
 601         InventoryAction *a = InventoryAction::deSerialize(is);
 602         if (!a) {
 603                 infostream << "TOSERVER_INVENTORY_ACTION: "
 604                                 << "InventoryAction::deSerialize() returned NULL"
 605                                 << std::endl;
 606                 return;
 607         }
 608
 609         // If something goes wrong, this player is to blame
 610         RollbackScopeActor rollback_scope(m_rollback,
 611                         std::string("player:")+player->getName());
 612
 613         /*
 614                 Note: Always set inventory not sent, to repair cases
 615                 where the client made a bad prediction.
 616         */
 617
 618         /*
 619                 Handle restrictions and special cases of the move action
 620         */
 621         if (a->getType() == IAction::Move) {
 622                 IMoveAction *ma = (IMoveAction*)a;
 623
 624                 ma->from_inv.applyCurrentPlayer(player->getName());
 625                 ma->to_inv.applyCurrentPlayer(player->getName());
 626
 627                 m_inventory_mgr->setInventoryModified(ma->from_inv);
 628                 if (ma->from_inv != ma->to_inv)
 629                         m_inventory_mgr->setInventoryModified(ma->to_inv);
 630
 631                 bool from_inv_is_current_player =
 632                         (ma->from_inv.type == InventoryLocation::PLAYER) &&
 633                         (ma->from_inv.name == player->getName());
 634
 635                 bool to_inv_is_current_player =
 636                         (ma->to_inv.type == InventoryLocation::PLAYER) &&
 637                         (ma->to_inv.name == player->getName());
 638
 639                 InventoryLocation *remote = from_inv_is_current_player ?
 640                         &ma->to_inv : &ma->from_inv;
 641
 642                 // Check for out-of-range interaction
 643                 if (remote->type == InventoryLocation::NODEMETA) {
 644                         v3f node_pos   = intToFloat(remote->p, BS);
 645                         v3f player_pos = player->getPlayerSAO()->getEyePosition();
 646                         f32 d = player_pos.getDistanceFrom(node_pos);
 647                         if (!checkInteractDistance(player, d, "inventory"))
 648                                 return;
 649                 }
 650
 651                 /*
 652                         Disable moving items out of craftpreview
 653                 */
 654                 if (ma->from_list == "craftpreview") {
 655                         infostream << "Ignoring IMoveAction from "
 656                                         << (ma->from_inv.dump()) << ":" << ma->from_list
 657                                         << " to " << (ma->to_inv.dump()) << ":" << ma->to_list
 658                                         << " because src is " << ma->from_list << std::endl;
 659                         delete a;
 660                         return;
 661                 }
 662
 663                 /*
 664                         Disable moving items into craftresult and craftpreview
 665                 */
 666                 if (ma->to_list == "craftpreview" || ma->to_list == "craftresult") {
 667                         infostream << "Ignoring IMoveAction from "
 668                                         << (ma->from_inv.dump()) << ":" << ma->from_list
 669                                         << " to " << (ma->to_inv.dump()) << ":" << ma->to_list
 670                                         << " because dst is " << ma->to_list << std::endl;
 671                         delete a;
 672                         return;
 673                 }
 674
 675                 // Disallow moving items in elsewhere than player's inventory
 676                 // if not allowed to interact
 677                 if (!checkPriv(player->getName(), "interact") &&
 678                                 (!from_inv_is_current_player ||
 679                                 !to_inv_is_current_player)) {
 680                         infostream << "Cannot move outside of player's inventory: "
 681                                         << "No interact privilege" << std::endl;
 682                         delete a;
 683                         return;
 684                 }
 685         }
 686         /*
 687                 Handle restrictions and special cases of the drop action
 688         */
 689         else if (a->getType() == IAction::Drop) {
 690                 IDropAction *da = (IDropAction*)a;
 691
 692                 da->from_inv.applyCurrentPlayer(player->getName());
 693
 694                 m_inventory_mgr->setInventoryModified(da->from_inv);
 695
 696                 /*
 697                         Disable dropping items out of craftpreview
 698                 */
 699                 if (da->from_list == "craftpreview") {
 700                         infostream << "Ignoring IDropAction from "
 701                                         << (da->from_inv.dump()) << ":" << da->from_list
 702                                         << " because src is " << da->from_list << std::endl;
 703                         delete a;
 704                         return;
 705                 }
 706
 707                 // Disallow dropping items if not allowed to interact
 708                 if (!checkPriv(player->getName(), "interact")) {
 709                         delete a;
 710                         return;
 711                 }
 712
 713                 // Disallow dropping items if dead
 714                 if (playersao->isDead()) {
 715                         infostream << "Ignoring IDropAction from "
 716                                         << (da->from_inv.dump()) << ":" << da->from_list
 717                                         << " because player is dead." << std::endl;
 718                         delete a;
 719                         return;
 720                 }
 721         }
 722         /*
 723                 Handle restrictions and special cases of the craft action
 724         */
 725         else if (a->getType() == IAction::Craft) {
 726                 ICraftAction *ca = (ICraftAction*)a;
 727
 728                 ca->craft_inv.applyCurrentPlayer(player->getName());
 729
 730                 m_inventory_mgr->setInventoryModified(ca->craft_inv);
 731
 732                 //bool craft_inv_is_current_player =
 733                 //      (ca->craft_inv.type == InventoryLocation::PLAYER) &&
 734                 //      (ca->craft_inv.name == player->getName());
 735
 736                 // Disallow crafting if not allowed to interact
 737                 if (!checkPriv(player->getName(), "interact")) {
 738                         infostream << "Cannot craft: "
 739                                         << "No interact privilege" << std::endl;
 740                         delete a;
 741                         return;
 742                 }
 743         }
 744
 745         // Do the action
 746         a->apply(m_inventory_mgr.get(), playersao, this);
 747         // Eat the action
 748         delete a;
 749 }
 750
 751 void Server::handleCommand_ChatMessage(NetworkPacket* pkt)
 752 {
 753         /*
 754                 u16 command
 755                 u16 length
 756                 wstring message
 757         */
 758         u16 len;
 759         *pkt >> len;
 760
 761         std::wstring message;
 762         for (u16 i = 0; i < len; i++) {
 763                 u16 tmp_wchar;
 764                 *pkt >> tmp_wchar;
 765
 766                 message += (wchar_t)tmp_wchar;
 767         }
 768
 769         session_t peer_id = pkt->getPeerId();
 770         RemotePlayer *player = m_env->getPlayer(peer_id);
 771         if (player == NULL) {
 772                 errorstream <<
 773                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 774                         peer_id << " disconnecting peer!" << std::endl;
 775                 DisconnectPeer(peer_id);
 776                 return;
 777         }
 778
 779         // Get player name of this client
 780         std::string name = player->getName();
 781         std::wstring wname = narrow_to_wide(name);
 782
 783         std::wstring answer_to_sender = handleChat(name, wname, message, true, player);
 784         if (!answer_to_sender.empty()) {
 785                 // Send the answer to sender
 786                 SendChatMessage(peer_id, ChatMessage(CHATMESSAGE_TYPE_NORMAL,
 787                         answer_to_sender, wname));
 788         }
 789 }
 790
 791 void Server::handleCommand_Damage(NetworkPacket* pkt)
 792 {
 793         u16 damage;
 794
 795         *pkt >> damage;
 796
 797         session_t peer_id = pkt->getPeerId();
 798         RemotePlayer *player = m_env->getPlayer(peer_id);
 799
 800         if (player == NULL) {
 801                 errorstream <<
 802                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 803                         peer_id << " disconnecting peer!" << std::endl;
 804                 DisconnectPeer(peer_id);
 805                 return;
 806         }
 807
 808         PlayerSAO *playersao = player->getPlayerSAO();
 809         if (playersao == NULL) {
 810                 errorstream <<
 811                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
 812                         peer_id << " disconnecting peer!" << std::endl;
 813                 DisconnectPeer(peer_id);
 814                 return;
 815         }
 816
 817         if (!playersao->isImmortal()) {
 818                 if (playersao->isDead()) {
 819                         verbosestream << "Server::ProcessData(): Info: "
 820                                 "Ignoring damage as player " << player->getName()
 821                                 << " is already dead." << std::endl;
 822                         return;
 823                 }
 824
 825                 actionstream << player->getName() << " damaged by "
 826                                 << (int)damage << " hp at " << PP(playersao->getBasePosition() / BS)
 827                                 << std::endl;
 828
 829                 PlayerHPChangeReason reason(PlayerHPChangeReason::FALL);
 830                 playersao->setHP((s32)playersao->getHP() - (s32)damage, reason);
 831                 SendPlayerHPOrDie(playersao, reason);
 832         }
 833 }
 834
 835 void Server::handleCommand_PlayerItem(NetworkPacket* pkt)
 836 {
 837         if (pkt->getSize() < 2)
 838                 return;
 839
 840         session_t peer_id = pkt->getPeerId();
 841         RemotePlayer *player = m_env->getPlayer(peer_id);
 842
 843         if (player == NULL) {
 844                 errorstream <<
 845                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 846                         peer_id << " disconnecting peer!" << std::endl;
 847                 DisconnectPeer(peer_id);
 848                 return;
 849         }
 850
 851         PlayerSAO *playersao = player->getPlayerSAO();
 852         if (playersao == NULL) {
 853                 errorstream <<
 854                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
 855                         peer_id << " disconnecting peer!" << std::endl;
 856                 DisconnectPeer(peer_id);
 857                 return;
 858         }
 859
 860         u16 item;
 861
 862         *pkt >> item;
 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         playersao->getPlayer()->setWieldIndex(item_i);
 980
 981         // Get pointed to node (undefined if not POINTEDTYPE_NODE)
 982         v3s16 p_under = pointed.node_undersurface;
 983         v3s16 p_above = pointed.node_abovesurface;
 984
 985         // Get pointed to object (NULL if not POINTEDTYPE_OBJECT)
 986         ServerActiveObject *pointed_object = NULL;
 987         if (pointed.type == POINTEDTHING_OBJECT) {
 988                 pointed_object = m_env->getActiveObject(pointed.object_id);
 989                 if (pointed_object == NULL) {
 990                         verbosestream << "TOSERVER_INTERACT: "
 991                                 "pointed object is NULL" << std::endl;
 992                         return;
 993                 }
 994
 995         }
 996
 997         v3f pointed_pos_under = player_pos;
 998         v3f pointed_pos_above = player_pos;
 999         if (pointed.type == POINTEDTHING_NODE) {
1000                 pointed_pos_under = intToFloat(p_under, BS);
1001                 pointed_pos_above = intToFloat(p_above, BS);
1002         }
1003         else if (pointed.type == POINTEDTHING_OBJECT) {
1004                 pointed_pos_under = pointed_object->getBasePosition();
1005                 pointed_pos_above = pointed_pos_under;
1006         }
1007
1008         /*
1009                 Make sure the player is allowed to do it
1010         */
1011         if (!checkPriv(player->getName(), "interact")) {
1012                 actionstream << player->getName() << " attempted to interact with " <<
1013                                 pointed.dump() << " without 'interact' privilege" << std::endl;
1014
1015                 // Re-send block to revert change on client-side
1016                 RemoteClient *client = getClient(peer_id);
1017                 // Digging completed -> under
1018                 if (action == INTERACT_DIGGING_COMPLETED) {
1019                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1020                         client->SetBlockNotSent(blockpos);
1021                 }
1022                 // Placement -> above
1023                 else if (action == INTERACT_PLACE) {
1024                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_above, BS));
1025                         client->SetBlockNotSent(blockpos);
1026                 }
1027                 return;
1028         }
1029
1030         /*
1031                 Check that target is reasonably close
1032                 (only when digging or placing things)
1033         */
1034         static thread_local const bool enable_anticheat =
1035                         !g_settings->getBool("disable_anticheat");
1036
1037         if ((action == INTERACT_START_DIGGING || action == INTERACT_DIGGING_COMPLETED ||
1038                         action == INTERACT_PLACE || action == INTERACT_USE) &&
1039                         enable_anticheat && !isSingleplayer()) {
1040                 float d = playersao->getEyePosition().getDistanceFrom(pointed_pos_under);
1041
1042                 if (!checkInteractDistance(player, d, pointed.dump())) {
1043                         // Re-send block to revert change on client-side
1044                         RemoteClient *client = getClient(peer_id);
1045                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1046                         client->SetBlockNotSent(blockpos);
1047                         return;
1048                 }
1049         }
1050
1051         /*
1052                 If something goes wrong, this player is to blame
1053         */
1054         RollbackScopeActor rollback_scope(m_rollback,
1055                         std::string("player:")+player->getName());
1056
1057         /*
1058                 0: start digging or punch object
1059         */
1060         if (action == INTERACT_START_DIGGING) {
1061                 if (pointed.type == POINTEDTHING_NODE) {
1062                         MapNode n(CONTENT_IGNORE);
1063                         bool pos_ok;
1064
1065                         n = m_env->getMap().getNode(p_under, &pos_ok);
1066                         if (!pos_ok) {
1067                                 infostream << "Server: Not punching: Node not found. "
1068                                         "Adding block to emerge queue." << std::endl;
1069                                 m_emerge->enqueueBlockEmerge(peer_id, getNodeBlockPos(p_above),
1070                                         false);
1071                         }
1072
1073                         if (n.getContent() != CONTENT_IGNORE)
1074                                 m_script->node_on_punch(p_under, n, playersao, pointed);
1075
1076                         // Cheat prevention
1077                         playersao->noCheatDigStart(p_under);
1078                 }
1079                 else if (pointed.type == POINTEDTHING_OBJECT) {
1080                         // Skip if object can't be interacted with anymore
1081                         if (pointed_object->isGone())
1082                                 return;
1083
1084                         ItemStack selected_item, hand_item;
1085                         ItemStack tool_item = playersao->getWieldedItem(&selected_item, &hand_item);
1086                         ToolCapabilities toolcap =
1087                                         tool_item.getToolCapabilities(m_itemdef);
1088                         v3f dir = (pointed_object->getBasePosition() -
1089                                         (playersao->getBasePosition() + playersao->getEyeOffset())
1090                                                 ).normalize();
1091                         float time_from_last_punch =
1092                                 playersao->resetTimeFromLastPunch();
1093
1094                         u16 src_original_hp = pointed_object->getHP();
1095                         u16 dst_origin_hp = playersao->getHP();
1096
1097                         u16 wear = pointed_object->punch(dir, &toolcap, playersao,
1098                                         time_from_last_punch);
1099
1100                         // Callback may have changed item, so get it again
1101                         playersao->getWieldedItem(&selected_item);
1102                         bool changed = selected_item.addWear(wear, m_itemdef);
1103                         if (changed)
1104                                 playersao->setWieldedItem(selected_item);
1105
1106                         // If the object is a player and its HP changed
1107                         if (src_original_hp != pointed_object->getHP() &&
1108                                         pointed_object->getType() == ACTIVEOBJECT_TYPE_PLAYER) {
1109                                 SendPlayerHPOrDie((PlayerSAO *)pointed_object,
1110                                                 PlayerHPChangeReason(PlayerHPChangeReason::PLAYER_PUNCH, playersao));
1111                         }
1112
1113                         // If the puncher is a player and its HP changed
1114                         if (dst_origin_hp != playersao->getHP())
1115                                 SendPlayerHPOrDie(playersao,
1116                                                 PlayerHPChangeReason(PlayerHPChangeReason::PLAYER_PUNCH, pointed_object));
1117                 }
1118
1119         } // action == INTERACT_START_DIGGING
1120
1121         /*
1122                 1: stop digging
1123         */
1124         else if (action == INTERACT_STOP_DIGGING) {
1125         } // action == INTERACT_STOP_DIGGING
1126
1127         /*
1128                 2: Digging completed
1129         */
1130         else if (action == INTERACT_DIGGING_COMPLETED) {
1131                 // Only digging of nodes
1132                 if (pointed.type == POINTEDTHING_NODE) {
1133                         bool pos_ok;
1134                         MapNode n = m_env->getMap().getNode(p_under, &pos_ok);
1135                         if (!pos_ok) {
1136                                 infostream << "Server: Not finishing digging: Node not found. "
1137                                         "Adding block to emerge queue." << std::endl;
1138                                 m_emerge->enqueueBlockEmerge(peer_id, getNodeBlockPos(p_above),
1139                                         false);
1140                         }
1141
1142                         /* Cheat prevention */
1143                         bool is_valid_dig = true;
1144                         if (enable_anticheat && !isSingleplayer()) {
1145                                 v3s16 nocheat_p = playersao->getNoCheatDigPos();
1146                                 float nocheat_t = playersao->getNoCheatDigTime();
1147                                 playersao->noCheatDigEnd();
1148                                 // If player didn't start digging this, ignore dig
1149                                 if (nocheat_p != p_under) {
1150                                         infostream << "Server: " << player->getName()
1151                                                         << " started digging "
1152                                                         << PP(nocheat_p) << " and completed digging "
1153                                                         << PP(p_under) << "; not digging." << std::endl;
1154                                         is_valid_dig = false;
1155                                         // Call callbacks
1156                                         m_script->on_cheat(playersao, "finished_unknown_dig");
1157                                 }
1158
1159                                 // Get player's wielded item
1160                                 // See also: Game::handleDigging
1161                                 ItemStack selected_item, hand_item;
1162                                 playersao->getPlayer()->getWieldedItem(&selected_item, &hand_item);
1163
1164                                 // Get diggability and expected digging time
1165                                 DigParams params = getDigParams(m_nodedef->get(n).groups,
1166                                                 &selected_item.getToolCapabilities(m_itemdef));
1167                                 // If can't dig, try hand
1168                                 if (!params.diggable) {
1169                                         params = getDigParams(m_nodedef->get(n).groups,
1170                                                 &hand_item.getToolCapabilities(m_itemdef));
1171                                 }
1172                                 // If can't dig, ignore dig
1173                                 if (!params.diggable) {
1174                                         infostream << "Server: " << player->getName()
1175                                                         << " completed digging " << PP(p_under)
1176                                                         << ", which is not diggable with tool; not digging."
1177                                                         << std::endl;
1178                                         is_valid_dig = false;
1179                                         // Call callbacks
1180                                         m_script->on_cheat(playersao, "dug_unbreakable");
1181                                 }
1182                                 // Check digging time
1183                                 // If already invalidated, we don't have to
1184                                 if (!is_valid_dig) {
1185                                         // Well not our problem then
1186                                 }
1187                                 // Clean and long dig
1188                                 else if (params.time > 2.0 && nocheat_t * 1.2 > params.time) {
1189                                         // All is good, but grab time from pool; don't care if
1190                                         // it's actually available
1191                                         playersao->getDigPool().grab(params.time);
1192                                 }
1193                                 // Short or laggy dig
1194                                 // Try getting the time from pool
1195                                 else if (playersao->getDigPool().grab(params.time)) {
1196                                         // All is good
1197                                 }
1198                                 // Dig not possible
1199                                 else {
1200                                         infostream << "Server: " << player->getName()
1201                                                         << " completed digging " << PP(p_under)
1202                                                         << "too fast; not digging." << std::endl;
1203                                         is_valid_dig = false;
1204                                         // Call callbacks
1205                                         m_script->on_cheat(playersao, "dug_too_fast");
1206                                 }
1207                         }
1208
1209                         /* Actually dig node */
1210
1211                         if (is_valid_dig && n.getContent() != CONTENT_IGNORE)
1212                                 m_script->node_on_dig(p_under, n, playersao);
1213
1214                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1215                         RemoteClient *client = getClient(peer_id);
1216                         // Send unusual result (that is, node not being removed)
1217                         if (m_env->getMap().getNode(p_under).getContent() != CONTENT_AIR) {
1218                                 // Re-send block to revert change on client-side
1219                                 client->SetBlockNotSent(blockpos);
1220                         }
1221                         else {
1222                                 client->ResendBlockIfOnWire(blockpos);
1223                         }
1224                 }
1225         } // action == INTERACT_DIGGING_COMPLETED
1226
1227         /*
1228                 3: place block or right-click object
1229         */
1230         else if (action == INTERACT_PLACE) {
1231                 ItemStack selected_item;
1232                 playersao->getWieldedItem(&selected_item, nullptr);
1233
1234                 // Reset build time counter
1235                 if (pointed.type == POINTEDTHING_NODE &&
1236                                 selected_item.getDefinition(m_itemdef).type == ITEM_NODE)
1237                         getClient(peer_id)->m_time_from_building = 0.0;
1238
1239                 if (pointed.type == POINTEDTHING_OBJECT) {
1240                         // Right click object
1241
1242                         // Skip if object can't be interacted with anymore
1243                         if (pointed_object->isGone())
1244                                 return;
1245
1246                         actionstream << player->getName() << " right-clicks object "
1247                                         << pointed.object_id << ": "
1248                                         << pointed_object->getDescription() << std::endl;
1249
1250                         // Do stuff
1251                         if (m_script->item_OnSecondaryUse(
1252                                         selected_item, playersao, pointed)) {
1253                                 if (playersao->setWieldedItem(selected_item)) {
1254                                         SendInventory(playersao, true);
1255                                 }
1256                         }
1257
1258                         pointed_object->rightClick(playersao);
1259                 } else if (m_script->item_OnPlace(
1260                                 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
1269                 // If item has node placement prediction, always send the
1270                 // blocks to make sure the client knows what exactly happened
1271                 RemoteClient *client = getClient(peer_id);
1272                 v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_above, BS));
1273                 v3s16 blockpos2 = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1274                 if (!selected_item.getDefinition(m_itemdef).node_placement_prediction.empty()) {
1275                         client->SetBlockNotSent(blockpos);
1276                         if (blockpos2 != blockpos) {
1277                                 client->SetBlockNotSent(blockpos2);
1278                         }
1279                 }
1280                 else {
1281                         client->ResendBlockIfOnWire(blockpos);
1282                         if (blockpos2 != blockpos) {
1283                                 client->ResendBlockIfOnWire(blockpos2);
1284                         }
1285                 }
1286         } // action == INTERACT_PLACE
1287
1288         /*
1289                 4: use
1290         */
1291         else if (action == INTERACT_USE) {
1292                 ItemStack selected_item;
1293                 playersao->getWieldedItem(&selected_item, nullptr);
1294
1295                 actionstream << player->getName() << " uses " << selected_item.name
1296                                 << ", pointing at " << pointed.dump() << std::endl;
1297
1298                 if (m_script->item_OnUse(
1299                                 selected_item, playersao, pointed)) {
1300                         // Apply returned ItemStack
1301                         if (playersao->setWieldedItem(selected_item)) {
1302                                 SendInventory(playersao, true);
1303                         }
1304                 }
1305
1306         } // action == INTERACT_USE
1307
1308         /*
1309                 5: rightclick air
1310         */
1311         else if (action == INTERACT_ACTIVATE) {
1312                 ItemStack selected_item;
1313                 playersao->getWieldedItem(&selected_item, nullptr);
1314
1315                 actionstream << player->getName() << " activates "
1316                                 << selected_item.name << std::endl;
1317
1318                 pointed.type = POINTEDTHING_NOTHING; // can only ever be NOTHING
1319
1320                 if (m_script->item_OnSecondaryUse(
1321                                 selected_item, playersao, pointed)) {
1322                         if (playersao->setWieldedItem(selected_item)) {
1323                                 SendInventory(playersao, true);
1324                         }
1325                 }
1326         } // action == INTERACT_ACTIVATE
1327
1328
1329         /*
1330                 Catch invalid actions
1331         */
1332         else {
1333                 warningstream << "Server: Invalid action "
1334                                 << action << std::endl;
1335         }
1336 }
1337
1338 void Server::handleCommand_RemovedSounds(NetworkPacket* pkt)
1339 {
1340         u16 num;
1341         *pkt >> num;
1342         for (u16 k = 0; k < num; k++) {
1343                 s32 id;
1344
1345                 *pkt >> id;
1346
1347                 std::unordered_map<s32, ServerPlayingSound>::iterator i =
1348                         m_playing_sounds.find(id);
1349                 if (i == m_playing_sounds.end())
1350                         continue;
1351
1352                 ServerPlayingSound &psound = i->second;
1353                 psound.clients.erase(pkt->getPeerId());
1354                 if (psound.clients.empty())
1355                         m_playing_sounds.erase(i++);
1356         }
1357 }
1358
1359 void Server::handleCommand_NodeMetaFields(NetworkPacket* pkt)
1360 {
1361         v3s16 p;
1362         std::string formname;
1363         u16 num;
1364
1365         *pkt >> p >> formname >> num;
1366
1367         StringMap fields;
1368         for (u16 k = 0; k < num; k++) {
1369                 std::string fieldname;
1370                 *pkt >> fieldname;
1371                 fields[fieldname] = pkt->readLongString();
1372         }
1373
1374         session_t peer_id = pkt->getPeerId();
1375         RemotePlayer *player = m_env->getPlayer(peer_id);
1376
1377         if (player == NULL) {
1378                 errorstream <<
1379                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
1380                         peer_id << " disconnecting peer!" << std::endl;
1381                 DisconnectPeer(peer_id);
1382                 return;
1383         }
1384
1385         PlayerSAO *playersao = player->getPlayerSAO();
1386         if (playersao == NULL) {
1387                 errorstream <<
1388                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
1389                         peer_id << " disconnecting peer!" << std::endl;
1390                 DisconnectPeer(peer_id);
1391                 return;
1392         }
1393
1394         // If something goes wrong, this player is to blame
1395         RollbackScopeActor rollback_scope(m_rollback,
1396                         std::string("player:")+player->getName());
1397
1398         // Check the target node for rollback data; leave others unnoticed
1399         RollbackNode rn_old(&m_env->getMap(), p, this);
1400
1401         m_script->node_on_receive_fields(p, formname, fields, playersao);
1402
1403         // Report rollback data
1404         RollbackNode rn_new(&m_env->getMap(), p, this);
1405         if (rollback() && rn_new != rn_old) {
1406                 RollbackAction action;
1407                 action.setSetNode(p, rn_old, rn_new);
1408                 rollback()->reportAction(action);
1409         }
1410 }
1411
1412 void Server::handleCommand_InventoryFields(NetworkPacket* pkt)
1413 {
1414         std::string client_formspec_name;
1415         u16 num;
1416
1417         *pkt >> client_formspec_name >> num;
1418
1419         StringMap fields;
1420         for (u16 k = 0; k < num; k++) {
1421                 std::string fieldname;
1422                 *pkt >> fieldname;
1423                 fields[fieldname] = pkt->readLongString();
1424         }
1425
1426         session_t peer_id = pkt->getPeerId();
1427         RemotePlayer *player = m_env->getPlayer(peer_id);
1428
1429         if (player == NULL) {
1430                 errorstream <<
1431                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
1432                         peer_id << " disconnecting peer!" << std::endl;
1433                 DisconnectPeer(peer_id);
1434                 return;
1435         }
1436
1437         PlayerSAO *playersao = player->getPlayerSAO();
1438         if (playersao == NULL) {
1439                 errorstream <<
1440                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
1441                         peer_id << " disconnecting peer!" << std::endl;
1442                 DisconnectPeer(peer_id);
1443                 return;
1444         }
1445
1446         if (client_formspec_name.empty()) { // pass through inventory submits
1447                 m_script->on_playerReceiveFields(playersao, client_formspec_name, fields);
1448                 return;
1449         }
1450
1451         // verify that we displayed the formspec to the user
1452         const auto peer_state_iterator = m_formspec_state_data.find(peer_id);
1453         if (peer_state_iterator != m_formspec_state_data.end()) {
1454                 const std::string &server_formspec_name = peer_state_iterator->second;
1455                 if (client_formspec_name == server_formspec_name) {
1456                         auto it = fields.find("quit");
1457                         if (it != fields.end() && it->second == "true")
1458                                 m_formspec_state_data.erase(peer_state_iterator);
1459
1460                         m_script->on_playerReceiveFields(playersao, client_formspec_name, fields);
1461                         return;
1462                 }
1463                 actionstream << "'" << player->getName()
1464                         << "' submitted formspec ('" << client_formspec_name
1465                         << "') but the name of the formspec doesn't match the"
1466                         " expected name ('" << server_formspec_name << "')";
1467
1468         } else {
1469                 actionstream << "'" << player->getName()
1470                         << "' submitted formspec ('" << client_formspec_name
1471                         << "') but server hasn't sent formspec to client";
1472         }
1473         actionstream << ", possible exploitation attempt" << std::endl;
1474 }
1475
1476 void Server::handleCommand_FirstSrp(NetworkPacket* pkt)
1477 {
1478         session_t peer_id = pkt->getPeerId();
1479         RemoteClient *client = getClient(peer_id, CS_Invalid);
1480         ClientState cstate = client->getState();
1481
1482         std::string playername = client->getName();
1483
1484         std::string salt;
1485         std::string verification_key;
1486
1487         std::string addr_s = getPeerAddress(peer_id).serializeString();
1488         u8 is_empty;
1489
1490         *pkt >> salt >> verification_key >> is_empty;
1491
1492         verbosestream << "Server: Got TOSERVER_FIRST_SRP from " << addr_s
1493                 << ", with is_empty=" << (is_empty == 1) << std::endl;
1494
1495         // Either this packet is sent because the user is new or to change the password
1496         if (cstate == CS_HelloSent) {
1497                 if (!client->isMechAllowed(AUTH_MECHANISM_FIRST_SRP)) {
1498                         actionstream << "Server: Client from " << addr_s
1499                                         << " tried to set password without being "
1500                                         << "authenticated, or the username being new." << std::endl;
1501                         DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1502                         return;
1503                 }
1504
1505                 if (!isSingleplayer() &&
1506                                 g_settings->getBool("disallow_empty_password") &&
1507                                 is_empty == 1) {
1508                         actionstream << "Server: " << playername
1509                                         << " supplied empty password from " << addr_s << std::endl;
1510                         DenyAccess(peer_id, SERVER_ACCESSDENIED_EMPTY_PASSWORD);
1511                         return;
1512                 }
1513
1514                 std::string initial_ver_key;
1515
1516                 initial_ver_key = encode_srp_verifier(verification_key, salt);
1517                 m_script->createAuth(playername, initial_ver_key);
1518                 m_script->on_authplayer(playername, addr_s, true);
1519
1520                 acceptAuth(peer_id, false);
1521         } else {
1522                 if (cstate < CS_SudoMode) {
1523                         infostream << "Server::ProcessData(): Ignoring TOSERVER_FIRST_SRP from "
1524                                         << addr_s << ": " << "Client has wrong state " << cstate << "."
1525                                         << std::endl;
1526                         return;
1527                 }
1528                 m_clients.event(peer_id, CSE_SudoLeave);
1529                 std::string pw_db_field = encode_srp_verifier(verification_key, salt);
1530                 bool success = m_script->setPassword(playername, pw_db_field);
1531                 if (success) {
1532                         actionstream << playername << " changes password" << std::endl;
1533                         SendChatMessage(peer_id, ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
1534                                 L"Password change successful."));
1535                 } else {
1536                         actionstream << playername <<
1537                                 " tries to change password but it fails" << std::endl;
1538                         SendChatMessage(peer_id, ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
1539                                 L"Password change failed or unavailable."));
1540                 }
1541         }
1542 }
1543
1544 void Server::handleCommand_SrpBytesA(NetworkPacket* pkt)
1545 {
1546         session_t peer_id = pkt->getPeerId();
1547         RemoteClient *client = getClient(peer_id, CS_Invalid);
1548         ClientState cstate = client->getState();
1549
1550         bool wantSudo = (cstate == CS_Active);
1551
1552         if (!((cstate == CS_HelloSent) || (cstate == CS_Active))) {
1553                 actionstream << "Server: got SRP _A packet in wrong state " << cstate <<
1554                         " from " << getPeerAddress(peer_id).serializeString() <<
1555                         ". Ignoring." << std::endl;
1556                 return;
1557         }
1558
1559         if (client->chosen_mech != AUTH_MECHANISM_NONE) {
1560                 actionstream << "Server: got SRP _A packet, while auth is already "
1561                         "going on with mech " << client->chosen_mech << " from " <<
1562                         getPeerAddress(peer_id).serializeString() <<
1563                         " (wantSudo=" << wantSudo << "). Ignoring." << std::endl;
1564                 if (wantSudo) {
1565                         DenySudoAccess(peer_id);
1566                         return;
1567                 }
1568
1569                 DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1570                 return;
1571         }
1572
1573         std::string bytes_A;
1574         u8 based_on;
1575         *pkt >> bytes_A >> based_on;
1576
1577         infostream << "Server: TOSERVER_SRP_BYTES_A received with "
1578                 << "based_on=" << int(based_on) << " and len_A="
1579                 << bytes_A.length() << "." << std::endl;
1580
1581         AuthMechanism chosen = (based_on == 0) ?
1582                 AUTH_MECHANISM_LEGACY_PASSWORD : AUTH_MECHANISM_SRP;
1583
1584         if (wantSudo) {
1585                 if (!client->isSudoMechAllowed(chosen)) {
1586                         actionstream << "Server: Player \"" << client->getName() <<
1587                                 "\" at " << getPeerAddress(peer_id).serializeString() <<
1588                                 " tried to change password using unallowed mech " << chosen <<
1589                                 "." << std::endl;
1590                         DenySudoAccess(peer_id);
1591                         return;
1592                 }
1593         } else {
1594                 if (!client->isMechAllowed(chosen)) {
1595                         actionstream << "Server: Client tried to authenticate from " <<
1596                                 getPeerAddress(peer_id).serializeString() <<
1597                                 " using unallowed mech " << chosen << "." << std::endl;
1598                         DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1599                         return;
1600                 }
1601         }
1602
1603         client->chosen_mech = chosen;
1604
1605         std::string salt;
1606         std::string verifier;
1607
1608         if (based_on == 0) {
1609
1610                 generate_srp_verifier_and_salt(client->getName(), client->enc_pwd,
1611                         &verifier, &salt);
1612         } else if (!decode_srp_verifier_and_salt(client->enc_pwd, &verifier, &salt)) {
1613                 // Non-base64 errors should have been catched in the init handler
1614                 actionstream << "Server: User " << client->getName() <<
1615                         " tried to log in, but srp verifier field was invalid (most likely "
1616                         "invalid base64)." << std::endl;
1617                 DenyAccess(peer_id, SERVER_ACCESSDENIED_SERVER_FAIL);
1618                 return;
1619         }
1620
1621         char *bytes_B = 0;
1622         size_t len_B = 0;
1623
1624         client->auth_data = srp_verifier_new(SRP_SHA256, SRP_NG_2048,
1625                 client->getName().c_str(),
1626                 (const unsigned char *) salt.c_str(), salt.size(),
1627                 (const unsigned char *) verifier.c_str(), verifier.size(),
1628                 (const unsigned char *) bytes_A.c_str(), bytes_A.size(),
1629                 NULL, 0,
1630                 (unsigned char **) &bytes_B, &len_B, NULL, NULL);
1631
1632         if (!bytes_B) {
1633                 actionstream << "Server: User " << client->getName()
1634                         << " tried to log in, SRP-6a safety check violated in _A handler."
1635                         << std::endl;
1636                 if (wantSudo) {
1637                         DenySudoAccess(peer_id);
1638                         return;
1639                 }
1640
1641                 DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1642                 return;
1643         }
1644
1645         NetworkPacket resp_pkt(TOCLIENT_SRP_BYTES_S_B, 0, peer_id);
1646         resp_pkt << salt << std::string(bytes_B, len_B);
1647         Send(&resp_pkt);
1648 }
1649
1650 void Server::handleCommand_SrpBytesM(NetworkPacket* pkt)
1651 {
1652         session_t peer_id = pkt->getPeerId();
1653         RemoteClient *client = getClient(peer_id, CS_Invalid);
1654         ClientState cstate = client->getState();
1655         std::string addr_s = getPeerAddress(pkt->getPeerId()).serializeString();
1656         std::string playername = client->getName();
1657
1658         bool wantSudo = (cstate == CS_Active);
1659
1660         verbosestream << "Server: Received TOCLIENT_SRP_BYTES_M." << std::endl;
1661
1662         if (!((cstate == CS_HelloSent) || (cstate == CS_Active))) {
1663                 actionstream << "Server: got SRP _M packet in wrong state "
1664                         << cstate << " from " << addr_s
1665                         << ". Ignoring." << std::endl;
1666                 return;
1667         }
1668
1669         if (client->chosen_mech != AUTH_MECHANISM_SRP &&
1670                         client->chosen_mech != AUTH_MECHANISM_LEGACY_PASSWORD) {
1671                 actionstream << "Server: got SRP _M packet, while auth"
1672                         << "is going on with mech " << client->chosen_mech << " from "
1673                         << addr_s << " (wantSudo=" << wantSudo << "). Denying." << std::endl;
1674                 if (wantSudo) {
1675                         DenySudoAccess(peer_id);
1676                         return;
1677                 }
1678
1679                 DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1680                 return;
1681         }
1682
1683         std::string bytes_M;
1684         *pkt >> bytes_M;
1685
1686         if (srp_verifier_get_session_key_length((SRPVerifier *) client->auth_data)
1687                         != bytes_M.size()) {
1688                 actionstream << "Server: User " << playername << " at " << addr_s
1689                         << " sent bytes_M with invalid length " << bytes_M.size() << std::endl;
1690                 DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1691                 return;
1692         }
1693
1694         unsigned char *bytes_HAMK = 0;
1695
1696         srp_verifier_verify_session((SRPVerifier *) client->auth_data,
1697                 (unsigned char *)bytes_M.c_str(), &bytes_HAMK);
1698
1699         if (!bytes_HAMK) {
1700                 if (wantSudo) {
1701                         actionstream << "Server: User " << playername << " at " << addr_s
1702                                 << " tried to change their password, but supplied wrong"
1703                                 << " (SRP) password for authentication." << std::endl;
1704                         DenySudoAccess(peer_id);
1705                         return;
1706                 }
1707
1708                 actionstream << "Server: User " << playername << " at " << addr_s
1709                         << " supplied wrong password (auth mechanism: SRP)." << std::endl;
1710                 m_script->on_authplayer(playername, addr_s, false);
1711                 DenyAccess(peer_id, SERVER_ACCESSDENIED_WRONG_PASSWORD);
1712                 return;
1713         }
1714
1715         if (client->create_player_on_auth_success) {
1716                 m_script->createAuth(playername, client->enc_pwd);
1717
1718                 std::string checkpwd; // not used, but needed for passing something
1719                 if (!m_script->getAuth(playername, &checkpwd, NULL)) {
1720                         actionstream << "Server: " << playername <<
1721                                 " cannot be authenticated (auth handler does not work?)" <<
1722                                 std::endl;
1723                         DenyAccess(peer_id, SERVER_ACCESSDENIED_SERVER_FAIL);
1724                         return;
1725                 }
1726                 client->create_player_on_auth_success = false;
1727         }
1728
1729         m_script->on_authplayer(playername, addr_s, true);
1730         acceptAuth(peer_id, wantSudo);
1731 }
1732
1733 /*
1734  * Mod channels
1735  */
1736
1737 void Server::handleCommand_ModChannelJoin(NetworkPacket *pkt)
1738 {
1739         std::string channel_name;
1740         *pkt >> channel_name;
1741
1742         session_t peer_id = pkt->getPeerId();
1743         NetworkPacket resp_pkt(TOCLIENT_MODCHANNEL_SIGNAL,
1744                 1 + 2 + channel_name.size(), peer_id);
1745
1746         // Send signal to client to notify join succeed or not
1747         if (g_settings->getBool("enable_mod_channels") &&
1748                         m_modchannel_mgr->joinChannel(channel_name, peer_id)) {
1749                 resp_pkt << (u8) MODCHANNEL_SIGNAL_JOIN_OK;
1750                 infostream << "Peer " << peer_id << " joined channel " <<
1751                         channel_name << std::endl;
1752         }
1753         else {
1754                 resp_pkt << (u8)MODCHANNEL_SIGNAL_JOIN_FAILURE;
1755                 infostream << "Peer " << peer_id << " tried to join channel " <<
1756                         channel_name << ", but was already registered." << std::endl;
1757         }
1758         resp_pkt << channel_name;
1759         Send(&resp_pkt);
1760 }
1761
1762 void Server::handleCommand_ModChannelLeave(NetworkPacket *pkt)
1763 {
1764         std::string channel_name;
1765         *pkt >> channel_name;
1766
1767         session_t peer_id = pkt->getPeerId();
1768         NetworkPacket resp_pkt(TOCLIENT_MODCHANNEL_SIGNAL,
1769                 1 + 2 + channel_name.size(), peer_id);
1770
1771         // Send signal to client to notify join succeed or not
1772         if (g_settings->getBool("enable_mod_channels") &&
1773                         m_modchannel_mgr->leaveChannel(channel_name, peer_id)) {
1774                 resp_pkt << (u8)MODCHANNEL_SIGNAL_LEAVE_OK;
1775                 infostream << "Peer " << peer_id << " left channel " << channel_name <<
1776                         std::endl;
1777         } else {
1778                 resp_pkt << (u8) MODCHANNEL_SIGNAL_LEAVE_FAILURE;
1779                 infostream << "Peer " << peer_id << " left channel " << channel_name <<
1780                         ", but was not registered." << std::endl;
1781         }
1782         resp_pkt << channel_name;
1783         Send(&resp_pkt);
1784 }
1785
1786 void Server::handleCommand_ModChannelMsg(NetworkPacket *pkt)
1787 {
1788         std::string channel_name, channel_msg;
1789         *pkt >> channel_name >> channel_msg;
1790
1791         session_t peer_id = pkt->getPeerId();
1792         verbosestream << "Mod channel message received from peer " << peer_id <<
1793                 " on channel " << channel_name << " message: " << channel_msg <<
1794                 std::endl;
1795
1796         // If mod channels are not enabled, discard message
1797         if (!g_settings->getBool("enable_mod_channels")) {
1798                 return;
1799         }
1800
1801         // If channel not registered, signal it and ignore message
1802         if (!m_modchannel_mgr->channelRegistered(channel_name)) {
1803                 NetworkPacket resp_pkt(TOCLIENT_MODCHANNEL_SIGNAL,
1804                         1 + 2 + channel_name.size(), peer_id);
1805                 resp_pkt << (u8)MODCHANNEL_SIGNAL_CHANNEL_NOT_REGISTERED << channel_name;
1806                 Send(&resp_pkt);
1807                 return;
1808         }
1809
1810         // @TODO: filter, rate limit
1811
1812         broadcastModChannelMessage(channel_name, channel_msg, peer_id);
1813 }