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 (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
 495         player->keyPressed = keyPressed;
 496         player->control.up    = (keyPressed & (0x1 << 0));
 497         player->control.down  = (keyPressed & (0x1 << 1));
 498         player->control.left  = (keyPressed & (0x1 << 2));
 499         player->control.right = (keyPressed & (0x1 << 3));
 500         player->control.jump  = (keyPressed & (0x1 << 4));
 501         player->control.aux1  = (keyPressed & (0x1 << 5));
 502         player->control.sneak = (keyPressed & (0x1 << 6));
 503         player->control.dig   = (keyPressed & (0x1 << 7));
 504         player->control.place = (keyPressed & (0x1 << 8));
 505         player->control.zoom  = (keyPressed & (0x1 << 9));
 506
 507         if (playersao->checkMovementCheat()) {
 508                 // Call callbacks
 509                 m_script->on_cheat(playersao, "moved_too_fast");
 510                 SendMovePlayer(pkt->getPeerId());
 511         }
 512 }
 513
 514 void Server::handleCommand_PlayerPos(NetworkPacket* pkt)
 515 {
 516         session_t peer_id = pkt->getPeerId();
 517         RemotePlayer *player = m_env->getPlayer(peer_id);
 518         if (player == NULL) {
 519                 errorstream <<
 520                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 521                         peer_id << " disconnecting peer!" << std::endl;
 522                 DisconnectPeer(peer_id);
 523                 return;
 524         }
 525
 526         PlayerSAO *playersao = player->getPlayerSAO();
 527         if (playersao == NULL) {
 528                 errorstream <<
 529                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
 530                         peer_id << " disconnecting peer!" << std::endl;
 531                 DisconnectPeer(peer_id);
 532                 return;
 533         }
 534
 535         // If player is dead we don't care of this packet
 536         if (playersao->isDead()) {
 537                 verbosestream << "TOSERVER_PLAYERPOS: " << player->getName()
 538                                 << " is dead. Ignoring packet";
 539                 return;
 540         }
 541
 542         process_PlayerPos(player, playersao, pkt);
 543 }
 544
 545 void Server::handleCommand_DeletedBlocks(NetworkPacket* pkt)
 546 {
 547         if (pkt->getSize() < 1)
 548                 return;
 549
 550         /*
 551                 [0] u16 command
 552                 [2] u8 count
 553                 [3] v3s16 pos_0
 554                 [3+6] v3s16 pos_1
 555                 ...
 556         */
 557
 558         u8 count;
 559         *pkt >> count;
 560
 561         RemoteClient *client = getClient(pkt->getPeerId());
 562
 563         if ((s16)pkt->getSize() < 1 + (int)count * 6) {
 564                 throw con::InvalidIncomingDataException
 565                                 ("DELETEDBLOCKS length is too short");
 566         }
 567
 568         for (u16 i = 0; i < count; i++) {
 569                 v3s16 p;
 570                 *pkt >> p;
 571                 client->SetBlockNotSent(p);
 572         }
 573 }
 574
 575 void Server::handleCommand_InventoryAction(NetworkPacket* pkt)
 576 {
 577         session_t peer_id = pkt->getPeerId();
 578         RemotePlayer *player = m_env->getPlayer(peer_id);
 579
 580         if (player == NULL) {
 581                 errorstream <<
 582                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 583                         peer_id << " disconnecting peer!" << std::endl;
 584                 DisconnectPeer(peer_id);
 585                 return;
 586         }
 587
 588         PlayerSAO *playersao = player->getPlayerSAO();
 589         if (playersao == NULL) {
 590                 errorstream <<
 591                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
 592                         peer_id << " disconnecting peer!" << std::endl;
 593                 DisconnectPeer(peer_id);
 594                 return;
 595         }
 596
 597         // Strip command and create a stream
 598         std::string datastring(pkt->getString(0), pkt->getSize());
 599         verbosestream << "TOSERVER_INVENTORY_ACTION: data=" << datastring
 600                 << std::endl;
 601         std::istringstream is(datastring, std::ios_base::binary);
 602         // Create an action
 603         std::unique_ptr<InventoryAction> a(InventoryAction::deSerialize(is));
 604         if (!a) {
 605                 infostream << "TOSERVER_INVENTORY_ACTION: "
 606                                 << "InventoryAction::deSerialize() returned NULL"
 607                                 << std::endl;
 608                 return;
 609         }
 610
 611         // If something goes wrong, this player is to blame
 612         RollbackScopeActor rollback_scope(m_rollback,
 613                         std::string("player:")+player->getName());
 614
 615         /*
 616                 Note: Always set inventory not sent, to repair cases
 617                 where the client made a bad prediction.
 618         */
 619
 620         const bool player_has_interact = checkPriv(player->getName(), "interact");
 621
 622         auto check_inv_access = [player, player_has_interact] (
 623                         const InventoryLocation &loc) -> bool {
 624                 if (loc.type == InventoryLocation::CURRENT_PLAYER)
 625                         return false; // Only used internally on the client, never sent
 626                 if (loc.type == InventoryLocation::PLAYER) {
 627                         // Allow access to own inventory in all cases
 628                         return loc.name == player->getName();
 629                 }
 630
 631                 if (!player_has_interact) {
 632                         infostream << "Cannot modify foreign inventory: "
 633                                         << "No interact privilege" << std::endl;
 634                         return false;
 635                 }
 636                 return true;
 637         };
 638
 639         /*
 640                 Handle restrictions and special cases of the move action
 641         */
 642         if (a->getType() == IAction::Move) {
 643                 IMoveAction *ma = (IMoveAction*)a.get();
 644
 645                 ma->from_inv.applyCurrentPlayer(player->getName());
 646                 ma->to_inv.applyCurrentPlayer(player->getName());
 647
 648                 m_inventory_mgr->setInventoryModified(ma->from_inv);
 649                 if (ma->from_inv != ma->to_inv)
 650                         m_inventory_mgr->setInventoryModified(ma->to_inv);
 651
 652                 if (!check_inv_access(ma->from_inv) ||
 653                                 !check_inv_access(ma->to_inv))
 654                         return;
 655
 656                 InventoryLocation *remote = ma->from_inv.type == InventoryLocation::PLAYER ?
 657                         &ma->to_inv : &ma->from_inv;
 658
 659                 // Check for out-of-range interaction
 660                 if (remote->type == InventoryLocation::NODEMETA) {
 661                         v3f node_pos   = intToFloat(remote->p, BS);
 662                         v3f player_pos = player->getPlayerSAO()->getEyePosition();
 663                         f32 d = player_pos.getDistanceFrom(node_pos);
 664                         if (!checkInteractDistance(player, d, "inventory"))
 665                                 return;
 666                 }
 667
 668                 /*
 669                         Disable moving items out of craftpreview
 670                 */
 671                 if (ma->from_list == "craftpreview") {
 672                         infostream << "Ignoring IMoveAction from "
 673                                         << (ma->from_inv.dump()) << ":" << ma->from_list
 674                                         << " to " << (ma->to_inv.dump()) << ":" << ma->to_list
 675                                         << " because src is " << ma->from_list << std::endl;
 676                         return;
 677                 }
 678
 679                 /*
 680                         Disable moving items into craftresult and craftpreview
 681                 */
 682                 if (ma->to_list == "craftpreview" || ma->to_list == "craftresult") {
 683                         infostream << "Ignoring IMoveAction from "
 684                                         << (ma->from_inv.dump()) << ":" << ma->from_list
 685                                         << " to " << (ma->to_inv.dump()) << ":" << ma->to_list
 686                                         << " because dst is " << ma->to_list << std::endl;
 687                         return;
 688                 }
 689         }
 690         /*
 691                 Handle restrictions and special cases of the drop action
 692         */
 693         else if (a->getType() == IAction::Drop) {
 694                 IDropAction *da = (IDropAction*)a.get();
 695
 696                 da->from_inv.applyCurrentPlayer(player->getName());
 697
 698                 m_inventory_mgr->setInventoryModified(da->from_inv);
 699
 700                 /*
 701                         Disable dropping items out of craftpreview
 702                 */
 703                 if (da->from_list == "craftpreview") {
 704                         infostream << "Ignoring IDropAction from "
 705                                         << (da->from_inv.dump()) << ":" << da->from_list
 706                                         << " because src is " << da->from_list << std::endl;
 707                         return;
 708                 }
 709
 710                 // Disallow dropping items if not allowed to interact
 711                 if (!player_has_interact || !check_inv_access(da->from_inv))
 712                         return;
 713
 714                 // Disallow dropping items if dead
 715                 if (playersao->isDead()) {
 716                         infostream << "Ignoring IDropAction from "
 717                                         << (da->from_inv.dump()) << ":" << da->from_list
 718                                         << " because player is dead." << std::endl;
 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.get();
 727
 728                 ca->craft_inv.applyCurrentPlayer(player->getName());
 729
 730                 m_inventory_mgr->setInventoryModified(ca->craft_inv);
 731
 732                 // Disallow crafting if not allowed to interact
 733                 if (!player_has_interact) {
 734                         infostream << "Cannot craft: "
 735                                         << "No interact privilege" << std::endl;
 736                         return;
 737                 }
 738
 739                 if (!check_inv_access(ca->craft_inv))
 740                         return;
 741         } else {
 742                 // Unknown action. Ignored.
 743                 return;
 744         }
 745
 746         // Do the action
 747         a->apply(m_inventory_mgr.get(), playersao, this);
 748 }
 749
 750 void Server::handleCommand_ChatMessage(NetworkPacket* pkt)
 751 {
 752         /*
 753                 u16 command
 754                 u16 length
 755                 wstring message
 756         */
 757         u16 len;
 758         *pkt >> len;
 759
 760         std::wstring message;
 761         for (u16 i = 0; i < len; i++) {
 762                 u16 tmp_wchar;
 763                 *pkt >> tmp_wchar;
 764
 765                 message += (wchar_t)tmp_wchar;
 766         }
 767
 768         session_t peer_id = pkt->getPeerId();
 769         RemotePlayer *player = m_env->getPlayer(peer_id);
 770         if (player == NULL) {
 771                 errorstream <<
 772                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 773                         peer_id << " disconnecting peer!" << std::endl;
 774                 DisconnectPeer(peer_id);
 775                 return;
 776         }
 777
 778         // Get player name of this client
 779         std::string name = player->getName();
 780         std::wstring wname = narrow_to_wide(name);
 781
 782         std::wstring answer_to_sender = handleChat(name, wname, message, true, player);
 783         if (!answer_to_sender.empty()) {
 784                 // Send the answer to sender
 785                 SendChatMessage(peer_id, ChatMessage(CHATMESSAGE_TYPE_NORMAL,
 786                         answer_to_sender, wname));
 787         }
 788 }
 789
 790 void Server::handleCommand_Damage(NetworkPacket* pkt)
 791 {
 792         u16 damage;
 793
 794         *pkt >> damage;
 795
 796         session_t peer_id = pkt->getPeerId();
 797         RemotePlayer *player = m_env->getPlayer(peer_id);
 798
 799         if (player == NULL) {
 800                 errorstream <<
 801                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 802                         peer_id << " disconnecting peer!" << std::endl;
 803                 DisconnectPeer(peer_id);
 804                 return;
 805         }
 806
 807         PlayerSAO *playersao = player->getPlayerSAO();
 808         if (playersao == NULL) {
 809                 errorstream <<
 810                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
 811                         peer_id << " disconnecting peer!" << std::endl;
 812                 DisconnectPeer(peer_id);
 813                 return;
 814         }
 815
 816         if (!playersao->isImmortal()) {
 817                 if (playersao->isDead()) {
 818                         verbosestream << "Server::ProcessData(): Info: "
 819                                 "Ignoring damage as player " << player->getName()
 820                                 << " is already dead." << std::endl;
 821                         return;
 822                 }
 823
 824                 actionstream << player->getName() << " damaged by "
 825                                 << (int)damage << " hp at " << PP(playersao->getBasePosition() / BS)
 826                                 << std::endl;
 827
 828                 PlayerHPChangeReason reason(PlayerHPChangeReason::FALL);
 829                 playersao->setHP((s32)playersao->getHP() - (s32)damage, reason);
 830                 SendPlayerHPOrDie(playersao, reason);
 831         }
 832 }
 833
 834 void Server::handleCommand_PlayerItem(NetworkPacket* pkt)
 835 {
 836         if (pkt->getSize() < 2)
 837                 return;
 838
 839         session_t peer_id = pkt->getPeerId();
 840         RemotePlayer *player = m_env->getPlayer(peer_id);
 841
 842         if (player == NULL) {
 843                 errorstream <<
 844                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 845                         peer_id << " disconnecting peer!" << std::endl;
 846                 DisconnectPeer(peer_id);
 847                 return;
 848         }
 849
 850         PlayerSAO *playersao = player->getPlayerSAO();
 851         if (playersao == NULL) {
 852                 errorstream <<
 853                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
 854                         peer_id << " disconnecting peer!" << std::endl;
 855                 DisconnectPeer(peer_id);
 856                 return;
 857         }
 858
 859         u16 item;
 860
 861         *pkt >> item;
 862
 863         if (item >= player->getHotbarItemcount()) {
 864                 actionstream << "Player: " << player->getName()
 865                         << " tried to access item=" << item
 866                         << " out of hotbar_itemcount="
 867                         << player->getHotbarItemcount()
 868                         << "; ignoring." << std::endl;
 869                 return;
 870         }
 871
 872         playersao->getPlayer()->setWieldIndex(item);
 873 }
 874
 875 void Server::handleCommand_Respawn(NetworkPacket* pkt)
 876 {
 877         session_t peer_id = pkt->getPeerId();
 878         RemotePlayer *player = m_env->getPlayer(peer_id);
 879         if (player == NULL) {
 880                 errorstream <<
 881                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 882                         peer_id << " disconnecting peer!" << std::endl;
 883                 DisconnectPeer(peer_id);
 884                 return;
 885         }
 886
 887         PlayerSAO *playersao = player->getPlayerSAO();
 888         assert(playersao);
 889
 890         if (!playersao->isDead())
 891                 return;
 892
 893         RespawnPlayer(peer_id);
 894
 895         actionstream << player->getName() << " respawns at "
 896                         << PP(playersao->getBasePosition() / BS) << std::endl;
 897
 898         // ActiveObject is added to environment in AsyncRunStep after
 899         // the previous addition has been successfully removed
 900 }
 901
 902 bool Server::checkInteractDistance(RemotePlayer *player, const f32 d, const std::string &what)
 903 {
 904         ItemStack selected_item, hand_item;
 905         player->getWieldedItem(&selected_item, &hand_item);
 906         f32 max_d = BS * getToolRange(selected_item.getDefinition(m_itemdef),
 907                         hand_item.getDefinition(m_itemdef));
 908
 909         // Cube diagonal * 1.5 for maximal supported node extents:
 910         // sqrt(3) * 1.5 ≅ 2.6
 911         if (d > max_d + 2.6f * BS) {
 912                 actionstream << "Player " << player->getName()
 913                                 << " tried to access " << what
 914                                 << " from too far: "
 915                                 << "d=" << d << ", max_d=" << max_d
 916                                 << "; ignoring." << std::endl;
 917                 // Call callbacks
 918                 m_script->on_cheat(player->getPlayerSAO(), "interacted_too_far");
 919                 return false;
 920         }
 921         return true;
 922 }
 923
 924 void Server::handleCommand_Interact(NetworkPacket *pkt)
 925 {
 926         /*
 927                 [0] u16 command
 928                 [2] u8 action
 929                 [3] u16 item
 930                 [5] u32 length of the next item (plen)
 931                 [9] serialized PointedThing
 932                 [9 + plen] player position information
 933         */
 934
 935         InteractAction action;
 936         u16 item_i;
 937
 938         *pkt >> (u8 &)action;
 939         *pkt >> item_i;
 940
 941         std::istringstream tmp_is(pkt->readLongString(), std::ios::binary);
 942         PointedThing pointed;
 943         pointed.deSerialize(tmp_is);
 944
 945         verbosestream << "TOSERVER_INTERACT: action=" << (int)action << ", item="
 946                         << item_i << ", pointed=" << pointed.dump() << std::endl;
 947
 948         session_t peer_id = pkt->getPeerId();
 949         RemotePlayer *player = m_env->getPlayer(peer_id);
 950
 951         if (player == NULL) {
 952                 errorstream <<
 953                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 954                         peer_id << " disconnecting peer!" << std::endl;
 955                 DisconnectPeer(peer_id);
 956                 return;
 957         }
 958
 959         PlayerSAO *playersao = player->getPlayerSAO();
 960         if (playersao == NULL) {
 961                 errorstream <<
 962                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
 963                         peer_id << " disconnecting peer!" << std::endl;
 964                 DisconnectPeer(peer_id);
 965                 return;
 966         }
 967
 968         if (playersao->isDead()) {
 969                 actionstream << "Server: " << player->getName()
 970                                 << " tried to interact while dead; ignoring." << std::endl;
 971                 if (pointed.type == POINTEDTHING_NODE) {
 972                         // Re-send block to revert change on client-side
 973                         RemoteClient *client = getClient(peer_id);
 974                         v3s16 blockpos = getNodeBlockPos(pointed.node_undersurface);
 975                         client->SetBlockNotSent(blockpos);
 976                 }
 977                 // Call callbacks
 978                 m_script->on_cheat(playersao, "interacted_while_dead");
 979                 return;
 980         }
 981
 982         process_PlayerPos(player, playersao, pkt);
 983
 984         v3f player_pos = playersao->getLastGoodPosition();
 985
 986         // Update wielded item
 987
 988         if (item_i >= player->getHotbarItemcount()) {
 989                 actionstream << "Player: " << player->getName()
 990                         << " tried to access item=" << item_i
 991                         << " out of hotbar_itemcount="
 992                         << player->getHotbarItemcount()
 993                         << "; ignoring." << std::endl;
 994                 return;
 995         }
 996
 997         playersao->getPlayer()->setWieldIndex(item_i);
 998
 999         // Get pointed to object (NULL if not POINTEDTYPE_OBJECT)
1000         ServerActiveObject *pointed_object = NULL;
1001         if (pointed.type == POINTEDTHING_OBJECT) {
1002                 pointed_object = m_env->getActiveObject(pointed.object_id);
1003                 if (pointed_object == NULL) {
1004                         verbosestream << "TOSERVER_INTERACT: "
1005                                 "pointed object is NULL" << std::endl;
1006                         return;
1007                 }
1008
1009         }
1010
1011         /*
1012                 Make sure the player is allowed to do it
1013         */
1014         if (!checkPriv(player->getName(), "interact")) {
1015                 actionstream << player->getName() << " attempted to interact with " <<
1016                                 pointed.dump() << " without 'interact' privilege" << std::endl;
1017
1018                 if (pointed.type != POINTEDTHING_NODE)
1019                         return;
1020
1021                 // Re-send block to revert change on client-side
1022                 RemoteClient *client = getClient(peer_id);
1023                 // Digging completed -> under
1024                 if (action == INTERACT_DIGGING_COMPLETED) {
1025                         v3s16 blockpos = getNodeBlockPos(pointed.node_undersurface);
1026                         client->SetBlockNotSent(blockpos);
1027                 }
1028                 // Placement -> above
1029                 else if (action == INTERACT_PLACE) {
1030                         v3s16 blockpos = getNodeBlockPos(pointed.node_abovesurface);
1031                         client->SetBlockNotSent(blockpos);
1032                 }
1033                 return;
1034         }
1035
1036         /*
1037                 Check that target is reasonably close
1038         */
1039         static thread_local const bool enable_anticheat =
1040                         !g_settings->getBool("disable_anticheat");
1041
1042         if ((action == INTERACT_START_DIGGING || action == INTERACT_DIGGING_COMPLETED ||
1043                         action == INTERACT_PLACE || action == INTERACT_USE) &&
1044                         enable_anticheat && !isSingleplayer()) {
1045                 v3f target_pos = player_pos;
1046                 if (pointed.type == POINTEDTHING_NODE) {
1047                         target_pos = intToFloat(pointed.node_undersurface, BS);
1048                 } else if (pointed.type == POINTEDTHING_OBJECT) {
1049                         target_pos = pointed_object->getBasePosition();
1050                 }
1051                 float d = playersao->getEyePosition().getDistanceFrom(target_pos);
1052
1053                 if (!checkInteractDistance(player, d, pointed.dump())) {
1054                         if (pointed.type == POINTEDTHING_NODE) {
1055                                 // Re-send block to revert change on client-side
1056                                 RemoteClient *client = getClient(peer_id);
1057                                 v3s16 blockpos = getNodeBlockPos(pointed.node_undersurface);
1058                                 client->SetBlockNotSent(blockpos);
1059                         }
1060                         return;
1061                 }
1062         }
1063
1064         /*
1065                 If something goes wrong, this player is to blame
1066         */
1067         RollbackScopeActor rollback_scope(m_rollback,
1068                         std::string("player:")+player->getName());
1069
1070         switch (action) {
1071         // Start digging or punch object
1072         case INTERACT_START_DIGGING: {
1073                 if (pointed.type == POINTEDTHING_NODE) {
1074                         MapNode n(CONTENT_IGNORE);
1075                         bool pos_ok;
1076
1077                         v3s16 p_under = pointed.node_undersurface;
1078                         n = m_env->getMap().getNode(p_under, &pos_ok);
1079                         if (!pos_ok) {
1080                                 infostream << "Server: Not punching: Node not found. "
1081                                         "Adding block to emerge queue." << std::endl;
1082                                 m_emerge->enqueueBlockEmerge(peer_id,
1083                                         getNodeBlockPos(pointed.node_abovesurface), false);
1084                         }
1085
1086                         if (n.getContent() != CONTENT_IGNORE)
1087                                 m_script->node_on_punch(p_under, n, playersao, pointed);
1088
1089                         // Cheat prevention
1090                         playersao->noCheatDigStart(p_under);
1091
1092                         return;
1093                 }
1094
1095                 // Skip if the object can't be interacted with anymore
1096                 if (pointed.type != POINTEDTHING_OBJECT || pointed_object->isGone())
1097                         return;
1098
1099                 ItemStack selected_item, hand_item;
1100                 ItemStack tool_item = playersao->getWieldedItem(&selected_item, &hand_item);
1101                 ToolCapabilities toolcap =
1102                                 tool_item.getToolCapabilities(m_itemdef);
1103                 v3f dir = (pointed_object->getBasePosition() -
1104                                 (playersao->getBasePosition() + playersao->getEyeOffset())
1105                                         ).normalize();
1106                 float time_from_last_punch =
1107                         playersao->resetTimeFromLastPunch();
1108
1109                 u16 src_original_hp = pointed_object->getHP();
1110                 u16 dst_origin_hp = playersao->getHP();
1111
1112                 u16 wear = pointed_object->punch(dir, &toolcap, playersao,
1113                                 time_from_last_punch);
1114
1115                 // Callback may have changed item, so get it again
1116                 playersao->getWieldedItem(&selected_item);
1117                 bool changed = selected_item.addWear(wear, m_itemdef);
1118                 if (changed)
1119                         playersao->setWieldedItem(selected_item);
1120
1121                 // If the object is a player and its HP changed
1122                 if (src_original_hp != pointed_object->getHP() &&
1123                                 pointed_object->getType() == ACTIVEOBJECT_TYPE_PLAYER) {
1124                         SendPlayerHPOrDie((PlayerSAO *)pointed_object,
1125                                         PlayerHPChangeReason(PlayerHPChangeReason::PLAYER_PUNCH, playersao));
1126                 }
1127
1128                 // If the puncher is a player and its HP changed
1129                 if (dst_origin_hp != playersao->getHP())
1130                         SendPlayerHPOrDie(playersao,
1131                                         PlayerHPChangeReason(PlayerHPChangeReason::PLAYER_PUNCH, pointed_object));
1132
1133                 return;
1134         } // action == INTERACT_START_DIGGING
1135
1136         case INTERACT_STOP_DIGGING:
1137                 // Nothing to do
1138                 return;
1139
1140         case INTERACT_DIGGING_COMPLETED: {
1141                 // Only digging of nodes
1142                 if (pointed.type != POINTEDTHING_NODE)
1143                         return;
1144                 bool pos_ok;
1145                 v3s16 p_under = pointed.node_undersurface;
1146                 MapNode n = m_env->getMap().getNode(p_under, &pos_ok);
1147                 if (!pos_ok) {
1148                         infostream << "Server: Not finishing digging: Node not found. "
1149                                 "Adding block to emerge queue." << std::endl;
1150                         m_emerge->enqueueBlockEmerge(peer_id,
1151                                 getNodeBlockPos(pointed.node_abovesurface), false);
1152                 }
1153
1154                 /* Cheat prevention */
1155                 bool is_valid_dig = true;
1156                 if (enable_anticheat && !isSingleplayer()) {
1157                         v3s16 nocheat_p = playersao->getNoCheatDigPos();
1158                         float nocheat_t = playersao->getNoCheatDigTime();
1159                         playersao->noCheatDigEnd();
1160                         // If player didn't start digging this, ignore dig
1161                         if (nocheat_p != p_under) {
1162                                 infostream << "Server: " << player->getName()
1163                                                 << " started digging "
1164                                                 << PP(nocheat_p) << " and completed digging "
1165                                                 << PP(p_under) << "; not digging." << std::endl;
1166                                 is_valid_dig = false;
1167                                 // Call callbacks
1168                                 m_script->on_cheat(playersao, "finished_unknown_dig");
1169                         }
1170
1171                         // Get player's wielded item
1172                         // See also: Game::handleDigging
1173                         ItemStack selected_item, hand_item;
1174                         playersao->getPlayer()->getWieldedItem(&selected_item, &hand_item);
1175
1176                         // Get diggability and expected digging time
1177                         DigParams params = getDigParams(m_nodedef->get(n).groups,
1178                                         &selected_item.getToolCapabilities(m_itemdef));
1179                         // If can't dig, try hand
1180                         if (!params.diggable) {
1181                                 params = getDigParams(m_nodedef->get(n).groups,
1182                                         &hand_item.getToolCapabilities(m_itemdef));
1183                         }
1184                         // If can't dig, ignore dig
1185                         if (!params.diggable) {
1186                                 infostream << "Server: " << player->getName()
1187                                                 << " completed digging " << PP(p_under)
1188                                                 << ", which is not diggable with tool; not digging."
1189                                                 << std::endl;
1190                                 is_valid_dig = false;
1191                                 // Call callbacks
1192                                 m_script->on_cheat(playersao, "dug_unbreakable");
1193                         }
1194                         // Check digging time
1195                         // If already invalidated, we don't have to
1196                         if (!is_valid_dig) {
1197                                 // Well not our problem then
1198                         }
1199                         // Clean and long dig
1200                         else if (params.time > 2.0 && nocheat_t * 1.2 > params.time) {
1201                                 // All is good, but grab time from pool; don't care if
1202                                 // it's actually available
1203                                 playersao->getDigPool().grab(params.time);
1204                         }
1205                         // Short or laggy dig
1206                         // Try getting the time from pool
1207                         else if (playersao->getDigPool().grab(params.time)) {
1208                                 // All is good
1209                         }
1210                         // Dig not possible
1211                         else {
1212                                 infostream << "Server: " << player->getName()
1213                                                 << " completed digging " << PP(p_under)
1214                                                 << "too fast; not digging." << std::endl;
1215                                 is_valid_dig = false;
1216                                 // Call callbacks
1217                                 m_script->on_cheat(playersao, "dug_too_fast");
1218                         }
1219                 }
1220
1221                 /* Actually dig node */
1222
1223                 if (is_valid_dig && n.getContent() != CONTENT_IGNORE)
1224                         m_script->node_on_dig(p_under, n, playersao);
1225
1226                 v3s16 blockpos = getNodeBlockPos(p_under);
1227                 RemoteClient *client = getClient(peer_id);
1228                 // Send unusual result (that is, node not being removed)
1229                 if (m_env->getMap().getNode(p_under).getContent() != CONTENT_AIR)
1230                         // Re-send block to revert change on client-side
1231                         client->SetBlockNotSent(blockpos);
1232                 else
1233                         client->ResendBlockIfOnWire(blockpos);
1234
1235                 return;
1236         } // action == INTERACT_DIGGING_COMPLETED
1237
1238         // Place block or right-click object
1239         case INTERACT_PLACE: {
1240                 ItemStack selected_item;
1241                 playersao->getWieldedItem(&selected_item, nullptr);
1242
1243                 // Reset build time counter
1244                 if (pointed.type == POINTEDTHING_NODE &&
1245                                 selected_item.getDefinition(m_itemdef).type == ITEM_NODE)
1246                         getClient(peer_id)->m_time_from_building = 0.0;
1247
1248                 if (pointed.type == POINTEDTHING_OBJECT) {
1249                         // Right click object
1250
1251                         // Skip if object can't be interacted with anymore
1252                         if (pointed_object->isGone())
1253                                 return;
1254
1255                         actionstream << player->getName() << " right-clicks object "
1256                                         << pointed.object_id << ": "
1257                                         << pointed_object->getDescription() << std::endl;
1258
1259                         // Do stuff
1260                         if (m_script->item_OnSecondaryUse(
1261                                         selected_item, playersao, pointed)) {
1262                                 if (playersao->setWieldedItem(selected_item)) {
1263                                         SendInventory(playersao, true);
1264                                 }
1265                         }
1266
1267                         pointed_object->rightClick(playersao);
1268                 } else if (m_script->item_OnPlace(selected_item, playersao, pointed)) {
1269                         // Placement was handled in lua
1270
1271                         // Apply returned ItemStack
1272                         if (playersao->setWieldedItem(selected_item))
1273                                 SendInventory(playersao, true);
1274                 }
1275
1276                 if (pointed.type != POINTEDTHING_NODE)
1277                         return;
1278
1279                 // If item has node placement prediction, always send the
1280                 // blocks to make sure the client knows what exactly happened
1281                 RemoteClient *client = getClient(peer_id);
1282                 v3s16 blockpos = getNodeBlockPos(pointed.node_abovesurface);
1283                 v3s16 blockpos2 = getNodeBlockPos(pointed.node_undersurface);
1284                 if (!selected_item.getDefinition(m_itemdef
1285                                 ).node_placement_prediction.empty()) {
1286                         client->SetBlockNotSent(blockpos);
1287                         if (blockpos2 != blockpos)
1288                                 client->SetBlockNotSent(blockpos2);
1289                 } else {
1290                         client->ResendBlockIfOnWire(blockpos);
1291                         if (blockpos2 != blockpos)
1292                                 client->ResendBlockIfOnWire(blockpos2);
1293                 }
1294
1295                 return;
1296         } // action == INTERACT_PLACE
1297
1298         case INTERACT_USE: {
1299                 ItemStack selected_item;
1300                 playersao->getWieldedItem(&selected_item, nullptr);
1301
1302                 actionstream << player->getName() << " uses " << selected_item.name
1303                                 << ", pointing at " << pointed.dump() << std::endl;
1304
1305                 if (m_script->item_OnUse(selected_item, playersao, pointed)) {
1306                         // Apply returned ItemStack
1307                         if (playersao->setWieldedItem(selected_item))
1308                                 SendInventory(playersao, true);
1309                 }
1310
1311                 return;
1312         }
1313
1314         // Rightclick air
1315         case INTERACT_ACTIVATE: {
1316                 ItemStack selected_item;
1317                 playersao->getWieldedItem(&selected_item, nullptr);
1318
1319                 actionstream << player->getName() << " activates "
1320                                 << selected_item.name << std::endl;
1321
1322                 pointed.type = POINTEDTHING_NOTHING; // can only ever be NOTHING
1323
1324                 if (m_script->item_OnSecondaryUse(selected_item, playersao, pointed)) {
1325                         if (playersao->setWieldedItem(selected_item))
1326                                 SendInventory(playersao, true);
1327                 }
1328
1329                 return;
1330         }
1331
1332         default:
1333                 warningstream << "Server: Invalid action " << action << std::endl;
1334
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 TOSERVER_SRP_BYTES_M." << std::endl;
1661
1662         if (!((cstate == CS_HelloSent) || (cstate == CS_Active))) {
1663                 warningstream << "Server: got SRP_M packet in wrong state "
1664                         << cstate << " from " << addr_s << ". Ignoring." << std::endl;
1665                 return;
1666         }
1667
1668         if (client->chosen_mech != AUTH_MECHANISM_SRP &&
1669                         client->chosen_mech != AUTH_MECHANISM_LEGACY_PASSWORD) {
1670                 warningstream << "Server: got SRP_M packet, while auth "
1671                         "is going on with mech " << client->chosen_mech << " from "
1672                         << addr_s << " (wantSudo=" << wantSudo << "). Denying." << std::endl;
1673                 if (wantSudo) {
1674                         DenySudoAccess(peer_id);
1675                         return;
1676                 }
1677
1678                 DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1679                 return;
1680         }
1681
1682         std::string bytes_M;
1683         *pkt >> bytes_M;
1684
1685         if (srp_verifier_get_session_key_length((SRPVerifier *) client->auth_data)
1686                         != bytes_M.size()) {
1687                 actionstream << "Server: User " << playername << " at " << addr_s
1688                         << " sent bytes_M with invalid length " << bytes_M.size() << std::endl;
1689                 DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1690                 return;
1691         }
1692
1693         unsigned char *bytes_HAMK = 0;
1694
1695         srp_verifier_verify_session((SRPVerifier *) client->auth_data,
1696                 (unsigned char *)bytes_M.c_str(), &bytes_HAMK);
1697
1698         if (!bytes_HAMK) {
1699                 if (wantSudo) {
1700                         actionstream << "Server: User " << playername << " at " << addr_s
1701                                 << " tried to change their password, but supplied wrong"
1702                                 << " (SRP) password for authentication." << std::endl;
1703                         DenySudoAccess(peer_id);
1704                         return;
1705                 }
1706
1707                 actionstream << "Server: User " << playername << " at " << addr_s
1708                         << " supplied wrong password (auth mechanism: SRP)." << std::endl;
1709                 m_script->on_authplayer(playername, addr_s, false);
1710                 DenyAccess(peer_id, SERVER_ACCESSDENIED_WRONG_PASSWORD);
1711                 return;
1712         }
1713
1714         if (client->create_player_on_auth_success) {
1715                 m_script->createAuth(playername, client->enc_pwd);
1716
1717                 std::string checkpwd; // not used, but needed for passing something
1718                 if (!m_script->getAuth(playername, &checkpwd, NULL)) {
1719                         errorstream << "Server: " << playername <<
1720                                 " cannot be authenticated (auth handler does not work?)" <<
1721                                 std::endl;
1722                         DenyAccess(peer_id, SERVER_ACCESSDENIED_SERVER_FAIL);
1723                         return;
1724                 }
1725                 client->create_player_on_auth_success = false;
1726         }
1727
1728         m_script->on_authplayer(playername, addr_s, true);
1729         acceptAuth(peer_id, wantSudo);
1730 }
1731
1732 /*
1733  * Mod channels
1734  */
1735
1736 void Server::handleCommand_ModChannelJoin(NetworkPacket *pkt)
1737 {
1738         std::string channel_name;
1739         *pkt >> channel_name;
1740
1741         session_t peer_id = pkt->getPeerId();
1742         NetworkPacket resp_pkt(TOCLIENT_MODCHANNEL_SIGNAL,
1743                 1 + 2 + channel_name.size(), peer_id);
1744
1745         // Send signal to client to notify join succeed or not
1746         if (g_settings->getBool("enable_mod_channels") &&
1747                         m_modchannel_mgr->joinChannel(channel_name, peer_id)) {
1748                 resp_pkt << (u8) MODCHANNEL_SIGNAL_JOIN_OK;
1749                 infostream << "Peer " << peer_id << " joined channel " <<
1750                         channel_name << std::endl;
1751         }
1752         else {
1753                 resp_pkt << (u8)MODCHANNEL_SIGNAL_JOIN_FAILURE;
1754                 infostream << "Peer " << peer_id << " tried to join channel " <<
1755                         channel_name << ", but was already registered." << std::endl;
1756         }
1757         resp_pkt << channel_name;
1758         Send(&resp_pkt);
1759 }
1760
1761 void Server::handleCommand_ModChannelLeave(NetworkPacket *pkt)
1762 {
1763         std::string channel_name;
1764         *pkt >> channel_name;
1765
1766         session_t peer_id = pkt->getPeerId();
1767         NetworkPacket resp_pkt(TOCLIENT_MODCHANNEL_SIGNAL,
1768                 1 + 2 + channel_name.size(), peer_id);
1769
1770         // Send signal to client to notify join succeed or not
1771         if (g_settings->getBool("enable_mod_channels") &&
1772                         m_modchannel_mgr->leaveChannel(channel_name, peer_id)) {
1773                 resp_pkt << (u8)MODCHANNEL_SIGNAL_LEAVE_OK;
1774                 infostream << "Peer " << peer_id << " left channel " << channel_name <<
1775                         std::endl;
1776         } else {
1777                 resp_pkt << (u8) MODCHANNEL_SIGNAL_LEAVE_FAILURE;
1778                 infostream << "Peer " << peer_id << " left channel " << channel_name <<
1779                         ", but was not registered." << std::endl;
1780         }
1781         resp_pkt << channel_name;
1782         Send(&resp_pkt);
1783 }
1784
1785 void Server::handleCommand_ModChannelMsg(NetworkPacket *pkt)
1786 {
1787         std::string channel_name, channel_msg;
1788         *pkt >> channel_name >> channel_msg;
1789
1790         session_t peer_id = pkt->getPeerId();
1791         verbosestream << "Mod channel message received from peer " << peer_id <<
1792                 " on channel " << channel_name << " message: " << channel_msg <<
1793                 std::endl;
1794
1795         // If mod channels are not enabled, discard message
1796         if (!g_settings->getBool("enable_mod_channels")) {
1797                 return;
1798         }
1799
1800         // If channel not registered, signal it and ignore message
1801         if (!m_modchannel_mgr->channelRegistered(channel_name)) {
1802                 NetworkPacket resp_pkt(TOCLIENT_MODCHANNEL_SIGNAL,
1803                         1 + 2 + channel_name.size(), peer_id);
1804                 resp_pkt << (u8)MODCHANNEL_SIGNAL_CHANNEL_NOT_REGISTERED << channel_name;
1805                 Send(&resp_pkt);
1806                 return;
1807         }
1808
1809         // @TODO: filter, rate limit
1810
1811         broadcastModChannelMessage(channel_name, channel_msg, peer_id);
1812 }