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
 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         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         /*
 621                 Handle restrictions and special cases of the move action
 622         */
 623         if (a->getType() == IAction::Move) {
 624                 IMoveAction *ma = (IMoveAction*)a;
 625
 626                 ma->from_inv.applyCurrentPlayer(player->getName());
 627                 ma->to_inv.applyCurrentPlayer(player->getName());
 628
 629                 m_inventory_mgr->setInventoryModified(ma->from_inv);
 630                 if (ma->from_inv != ma->to_inv)
 631                         m_inventory_mgr->setInventoryModified(ma->to_inv);
 632
 633                 bool from_inv_is_current_player = false;
 634                 if (ma->from_inv.type == InventoryLocation::PLAYER) {
 635                         if (ma->from_inv.name != player->getName())
 636                                 return;
 637                         from_inv_is_current_player = true;
 638                 }
 639
 640                 bool to_inv_is_current_player = false;
 641                 if (ma->to_inv.type == InventoryLocation::PLAYER) {
 642                         if (ma->to_inv.name != player->getName())
 643                                 return;
 644                         to_inv_is_current_player = true;
 645                 }
 646
 647                 InventoryLocation *remote = from_inv_is_current_player ?
 648                         &ma->to_inv : &ma->from_inv;
 649
 650                 // Check for out-of-range interaction
 651                 if (remote->type == InventoryLocation::NODEMETA) {
 652                         v3f node_pos   = intToFloat(remote->p, BS);
 653                         v3f player_pos = player->getPlayerSAO()->getEyePosition();
 654                         f32 d = player_pos.getDistanceFrom(node_pos);
 655                         if (!checkInteractDistance(player, d, "inventory"))
 656                                 return;
 657                 }
 658
 659                 /*
 660                         Disable moving items out of craftpreview
 661                 */
 662                 if (ma->from_list == "craftpreview") {
 663                         infostream << "Ignoring IMoveAction from "
 664                                         << (ma->from_inv.dump()) << ":" << ma->from_list
 665                                         << " to " << (ma->to_inv.dump()) << ":" << ma->to_list
 666                                         << " because src is " << ma->from_list << std::endl;
 667                         delete a;
 668                         return;
 669                 }
 670
 671                 /*
 672                         Disable moving items into craftresult and craftpreview
 673                 */
 674                 if (ma->to_list == "craftpreview" || ma->to_list == "craftresult") {
 675                         infostream << "Ignoring IMoveAction from "
 676                                         << (ma->from_inv.dump()) << ":" << ma->from_list
 677                                         << " to " << (ma->to_inv.dump()) << ":" << ma->to_list
 678                                         << " because dst is " << ma->to_list << std::endl;
 679                         delete a;
 680                         return;
 681                 }
 682
 683                 // Disallow moving items in elsewhere than player's inventory
 684                 // if not allowed to interact
 685                 if (!checkPriv(player->getName(), "interact") &&
 686                                 (!from_inv_is_current_player ||
 687                                 !to_inv_is_current_player)) {
 688                         infostream << "Cannot move outside of player's inventory: "
 689                                         << "No interact privilege" << std::endl;
 690                         delete a;
 691                         return;
 692                 }
 693         }
 694         /*
 695                 Handle restrictions and special cases of the drop action
 696         */
 697         else if (a->getType() == IAction::Drop) {
 698                 IDropAction *da = (IDropAction*)a;
 699
 700                 da->from_inv.applyCurrentPlayer(player->getName());
 701
 702                 m_inventory_mgr->setInventoryModified(da->from_inv);
 703
 704                 /*
 705                         Disable dropping items out of craftpreview
 706                 */
 707                 if (da->from_list == "craftpreview") {
 708                         infostream << "Ignoring IDropAction from "
 709                                         << (da->from_inv.dump()) << ":" << da->from_list
 710                                         << " because src is " << da->from_list << std::endl;
 711                         delete a;
 712                         return;
 713                 }
 714
 715                 // Disallow dropping items if not allowed to interact
 716                 if (!checkPriv(player->getName(), "interact")) {
 717                         delete a;
 718                         return;
 719                 }
 720
 721                 // Disallow dropping items if dead
 722                 if (playersao->isDead()) {
 723                         infostream << "Ignoring IDropAction from "
 724                                         << (da->from_inv.dump()) << ":" << da->from_list
 725                                         << " because player is dead." << std::endl;
 726                         delete a;
 727                         return;
 728                 }
 729         }
 730         /*
 731                 Handle restrictions and special cases of the craft action
 732         */
 733         else if (a->getType() == IAction::Craft) {
 734                 ICraftAction *ca = (ICraftAction*)a;
 735
 736                 ca->craft_inv.applyCurrentPlayer(player->getName());
 737
 738                 m_inventory_mgr->setInventoryModified(ca->craft_inv);
 739
 740                 //bool craft_inv_is_current_player =
 741                 //      (ca->craft_inv.type == InventoryLocation::PLAYER) &&
 742                 //      (ca->craft_inv.name == player->getName());
 743
 744                 // Disallow crafting if not allowed to interact
 745                 if (!checkPriv(player->getName(), "interact")) {
 746                         infostream << "Cannot craft: "
 747                                         << "No interact privilege" << std::endl;
 748                         delete a;
 749                         return;
 750                 }
 751         }
 752
 753         // Do the action
 754         a->apply(m_inventory_mgr.get(), playersao, this);
 755         // Eat the action
 756         delete a;
 757 }
 758
 759 void Server::handleCommand_ChatMessage(NetworkPacket* pkt)
 760 {
 761         /*
 762                 u16 command
 763                 u16 length
 764                 wstring message
 765         */
 766         u16 len;
 767         *pkt >> len;
 768
 769         std::wstring message;
 770         for (u16 i = 0; i < len; i++) {
 771                 u16 tmp_wchar;
 772                 *pkt >> tmp_wchar;
 773
 774                 message += (wchar_t)tmp_wchar;
 775         }
 776
 777         session_t peer_id = pkt->getPeerId();
 778         RemotePlayer *player = m_env->getPlayer(peer_id);
 779         if (player == NULL) {
 780                 errorstream <<
 781                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 782                         peer_id << " disconnecting peer!" << std::endl;
 783                 DisconnectPeer(peer_id);
 784                 return;
 785         }
 786
 787         // Get player name of this client
 788         std::string name = player->getName();
 789         std::wstring wname = narrow_to_wide(name);
 790
 791         std::wstring answer_to_sender = handleChat(name, wname, message, true, player);
 792         if (!answer_to_sender.empty()) {
 793                 // Send the answer to sender
 794                 SendChatMessage(peer_id, ChatMessage(CHATMESSAGE_TYPE_NORMAL,
 795                         answer_to_sender, wname));
 796         }
 797 }
 798
 799 void Server::handleCommand_Damage(NetworkPacket* pkt)
 800 {
 801         u16 damage;
 802
 803         *pkt >> damage;
 804
 805         session_t peer_id = pkt->getPeerId();
 806         RemotePlayer *player = m_env->getPlayer(peer_id);
 807
 808         if (player == NULL) {
 809                 errorstream <<
 810                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 811                         peer_id << " disconnecting peer!" << std::endl;
 812                 DisconnectPeer(peer_id);
 813                 return;
 814         }
 815
 816         PlayerSAO *playersao = player->getPlayerSAO();
 817         if (playersao == NULL) {
 818                 errorstream <<
 819                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
 820                         peer_id << " disconnecting peer!" << std::endl;
 821                 DisconnectPeer(peer_id);
 822                 return;
 823         }
 824
 825         if (!playersao->isImmortal()) {
 826                 if (playersao->isDead()) {
 827                         verbosestream << "Server::ProcessData(): Info: "
 828                                 "Ignoring damage as player " << player->getName()
 829                                 << " is already dead." << std::endl;
 830                         return;
 831                 }
 832
 833                 actionstream << player->getName() << " damaged by "
 834                                 << (int)damage << " hp at " << PP(playersao->getBasePosition() / BS)
 835                                 << std::endl;
 836
 837                 PlayerHPChangeReason reason(PlayerHPChangeReason::FALL);
 838                 playersao->setHP((s32)playersao->getHP() - (s32)damage, reason);
 839                 SendPlayerHPOrDie(playersao, reason);
 840         }
 841 }
 842
 843 void Server::handleCommand_PlayerItem(NetworkPacket* pkt)
 844 {
 845         if (pkt->getSize() < 2)
 846                 return;
 847
 848         session_t peer_id = pkt->getPeerId();
 849         RemotePlayer *player = m_env->getPlayer(peer_id);
 850
 851         if (player == NULL) {
 852                 errorstream <<
 853                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 854                         peer_id << " disconnecting peer!" << std::endl;
 855                 DisconnectPeer(peer_id);
 856                 return;
 857         }
 858
 859         PlayerSAO *playersao = player->getPlayerSAO();
 860         if (playersao == NULL) {
 861                 errorstream <<
 862                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
 863                         peer_id << " disconnecting peer!" << std::endl;
 864                 DisconnectPeer(peer_id);
 865                 return;
 866         }
 867
 868         u16 item;
 869
 870         *pkt >> item;
 871
 872         if (item >= player->getHotbarItemcount()) {
 873                 actionstream << "Player: " << player->getName()
 874                         << " tried to access item=" << item
 875                         << " out of hotbar_itemcount="
 876                         << player->getHotbarItemcount()
 877                         << "; ignoring." << std::endl;
 878                 return;
 879         }
 880
 881         playersao->getPlayer()->setWieldIndex(item);
 882 }
 883
 884 void Server::handleCommand_Respawn(NetworkPacket* pkt)
 885 {
 886         session_t peer_id = pkt->getPeerId();
 887         RemotePlayer *player = m_env->getPlayer(peer_id);
 888         if (player == NULL) {
 889                 errorstream <<
 890                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 891                         peer_id << " disconnecting peer!" << std::endl;
 892                 DisconnectPeer(peer_id);
 893                 return;
 894         }
 895
 896         PlayerSAO *playersao = player->getPlayerSAO();
 897         assert(playersao);
 898
 899         if (!playersao->isDead())
 900                 return;
 901
 902         RespawnPlayer(peer_id);
 903
 904         actionstream << player->getName() << " respawns at "
 905                         << PP(playersao->getBasePosition() / BS) << std::endl;
 906
 907         // ActiveObject is added to environment in AsyncRunStep after
 908         // the previous addition has been successfully removed
 909 }
 910
 911 bool Server::checkInteractDistance(RemotePlayer *player, const f32 d, const std::string &what)
 912 {
 913         ItemStack selected_item, hand_item;
 914         player->getWieldedItem(&selected_item, &hand_item);
 915         f32 max_d = BS * getToolRange(selected_item.getDefinition(m_itemdef),
 916                         hand_item.getDefinition(m_itemdef));
 917
 918         // Cube diagonal * 1.5 for maximal supported node extents:
 919         // sqrt(3) * 1.5 ≅ 2.6
 920         if (d > max_d + 2.6f * BS) {
 921                 actionstream << "Player " << player->getName()
 922                                 << " tried to access " << what
 923                                 << " from too far: "
 924                                 << "d=" << d << ", max_d=" << max_d
 925                                 << "; ignoring." << std::endl;
 926                 // Call callbacks
 927                 m_script->on_cheat(player->getPlayerSAO(), "interacted_too_far");
 928                 return false;
 929         }
 930         return true;
 931 }
 932
 933 void Server::handleCommand_Interact(NetworkPacket *pkt)
 934 {
 935         /*
 936                 [0] u16 command
 937                 [2] u8 action
 938                 [3] u16 item
 939                 [5] u32 length of the next item (plen)
 940                 [9] serialized PointedThing
 941                 [9 + plen] player position information
 942         */
 943
 944         InteractAction action;
 945         u16 item_i;
 946
 947         *pkt >> (u8 &)action;
 948         *pkt >> item_i;
 949
 950         std::istringstream tmp_is(pkt->readLongString(), std::ios::binary);
 951         PointedThing pointed;
 952         pointed.deSerialize(tmp_is);
 953
 954         verbosestream << "TOSERVER_INTERACT: action=" << (int)action << ", item="
 955                         << item_i << ", pointed=" << pointed.dump() << std::endl;
 956
 957         session_t peer_id = pkt->getPeerId();
 958         RemotePlayer *player = m_env->getPlayer(peer_id);
 959
 960         if (player == NULL) {
 961                 errorstream <<
 962                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
 963                         peer_id << " disconnecting peer!" << std::endl;
 964                 DisconnectPeer(peer_id);
 965                 return;
 966         }
 967
 968         PlayerSAO *playersao = player->getPlayerSAO();
 969         if (playersao == NULL) {
 970                 errorstream <<
 971                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
 972                         peer_id << " disconnecting peer!" << std::endl;
 973                 DisconnectPeer(peer_id);
 974                 return;
 975         }
 976
 977         if (playersao->isDead()) {
 978                 actionstream << "Server: " << player->getName()
 979                                 << " tried to interact while dead; ignoring." << std::endl;
 980                 if (pointed.type == POINTEDTHING_NODE) {
 981                         // Re-send block to revert change on client-side
 982                         RemoteClient *client = getClient(peer_id);
 983                         v3s16 blockpos = getNodeBlockPos(pointed.node_undersurface);
 984                         client->SetBlockNotSent(blockpos);
 985                 }
 986                 // Call callbacks
 987                 m_script->on_cheat(playersao, "interacted_while_dead");
 988                 return;
 989         }
 990
 991         process_PlayerPos(player, playersao, pkt);
 992
 993         v3f player_pos = playersao->getLastGoodPosition();
 994
 995         // Update wielded item
 996
 997         if (item_i >= player->getHotbarItemcount()) {
 998                 actionstream << "Player: " << player->getName()
 999                         << " tried to access item=" << item_i
1000                         << " out of hotbar_itemcount="
1001                         << player->getHotbarItemcount()
1002                         << "; ignoring." << std::endl;
1003                 return;
1004         }
1005
1006         playersao->getPlayer()->setWieldIndex(item_i);
1007
1008         // Get pointed to object (NULL if not POINTEDTYPE_OBJECT)
1009         ServerActiveObject *pointed_object = NULL;
1010         if (pointed.type == POINTEDTHING_OBJECT) {
1011                 pointed_object = m_env->getActiveObject(pointed.object_id);
1012                 if (pointed_object == NULL) {
1013                         verbosestream << "TOSERVER_INTERACT: "
1014                                 "pointed object is NULL" << std::endl;
1015                         return;
1016                 }
1017
1018         }
1019
1020         /*
1021                 Make sure the player is allowed to do it
1022         */
1023         if (!checkPriv(player->getName(), "interact")) {
1024                 actionstream << player->getName() << " attempted to interact with " <<
1025                                 pointed.dump() << " without 'interact' privilege" << std::endl;
1026
1027                 if (pointed.type != POINTEDTHING_NODE)
1028                         return;
1029
1030                 // Re-send block to revert change on client-side
1031                 RemoteClient *client = getClient(peer_id);
1032                 // Digging completed -> under
1033                 if (action == INTERACT_DIGGING_COMPLETED) {
1034                         v3s16 blockpos = getNodeBlockPos(pointed.node_undersurface);
1035                         client->SetBlockNotSent(blockpos);
1036                 }
1037                 // Placement -> above
1038                 else if (action == INTERACT_PLACE) {
1039                         v3s16 blockpos = getNodeBlockPos(pointed.node_abovesurface);
1040                         client->SetBlockNotSent(blockpos);
1041                 }
1042                 return;
1043         }
1044
1045         /*
1046                 Check that target is reasonably close
1047         */
1048         static thread_local const bool enable_anticheat =
1049                         !g_settings->getBool("disable_anticheat");
1050
1051         if ((action == INTERACT_START_DIGGING || action == INTERACT_DIGGING_COMPLETED ||
1052                         action == INTERACT_PLACE || action == INTERACT_USE) &&
1053                         enable_anticheat && !isSingleplayer()) {
1054                 v3f target_pos = player_pos;
1055                 if (pointed.type == POINTEDTHING_NODE) {
1056                         target_pos = intToFloat(pointed.node_undersurface, BS);
1057                 } else if (pointed.type == POINTEDTHING_OBJECT) {
1058                         target_pos = pointed_object->getBasePosition();
1059                 }
1060                 float d = playersao->getEyePosition().getDistanceFrom(target_pos);
1061
1062                 if (!checkInteractDistance(player, d, pointed.dump())
1063                                 && pointed.type == POINTEDTHING_NODE) {
1064                         // Re-send block to revert change on client-side
1065                         RemoteClient *client = getClient(peer_id);
1066                         v3s16 blockpos = getNodeBlockPos(pointed.node_undersurface);
1067                         client->SetBlockNotSent(blockpos);
1068                         return;
1069                 }
1070         }
1071
1072         /*
1073                 If something goes wrong, this player is to blame
1074         */
1075         RollbackScopeActor rollback_scope(m_rollback,
1076                         std::string("player:")+player->getName());
1077
1078         switch (action) {
1079         // Start digging or punch object
1080         case INTERACT_START_DIGGING: {
1081                 if (pointed.type == POINTEDTHING_NODE) {
1082                         MapNode n(CONTENT_IGNORE);
1083                         bool pos_ok;
1084
1085                         v3s16 p_under = pointed.node_undersurface;
1086                         n = m_env->getMap().getNode(p_under, &pos_ok);
1087                         if (!pos_ok) {
1088                                 infostream << "Server: Not punching: Node not found. "
1089                                         "Adding block to emerge queue." << std::endl;
1090                                 m_emerge->enqueueBlockEmerge(peer_id,
1091                                         getNodeBlockPos(pointed.node_abovesurface), false);
1092                         }
1093
1094                         if (n.getContent() != CONTENT_IGNORE)
1095                                 m_script->node_on_punch(p_under, n, playersao, pointed);
1096
1097                         // Cheat prevention
1098                         playersao->noCheatDigStart(p_under);
1099
1100                         return;
1101                 }
1102
1103                 // Skip if the object can't be interacted with anymore
1104                 if (pointed.type != POINTEDTHING_OBJECT || pointed_object->isGone())
1105                         return;
1106
1107                 ItemStack selected_item, hand_item;
1108                 ItemStack tool_item = playersao->getWieldedItem(&selected_item, &hand_item);
1109                 ToolCapabilities toolcap =
1110                                 tool_item.getToolCapabilities(m_itemdef);
1111                 v3f dir = (pointed_object->getBasePosition() -
1112                                 (playersao->getBasePosition() + playersao->getEyeOffset())
1113                                         ).normalize();
1114                 float time_from_last_punch =
1115                         playersao->resetTimeFromLastPunch();
1116
1117                 u16 src_original_hp = pointed_object->getHP();
1118                 u16 dst_origin_hp = playersao->getHP();
1119
1120                 u16 wear = pointed_object->punch(dir, &toolcap, playersao,
1121                                 time_from_last_punch);
1122
1123                 // Callback may have changed item, so get it again
1124                 playersao->getWieldedItem(&selected_item);
1125                 bool changed = selected_item.addWear(wear, m_itemdef);
1126                 if (changed)
1127                         playersao->setWieldedItem(selected_item);
1128
1129                 // If the object is a player and its HP changed
1130                 if (src_original_hp != pointed_object->getHP() &&
1131                                 pointed_object->getType() == ACTIVEOBJECT_TYPE_PLAYER) {
1132                         SendPlayerHPOrDie((PlayerSAO *)pointed_object,
1133                                         PlayerHPChangeReason(PlayerHPChangeReason::PLAYER_PUNCH, playersao));
1134                 }
1135
1136                 // If the puncher is a player and its HP changed
1137                 if (dst_origin_hp != playersao->getHP())
1138                         SendPlayerHPOrDie(playersao,
1139                                         PlayerHPChangeReason(PlayerHPChangeReason::PLAYER_PUNCH, pointed_object));
1140
1141                 return;
1142         } // action == INTERACT_START_DIGGING
1143
1144         case INTERACT_STOP_DIGGING:
1145                 // Nothing to do
1146                 return;
1147
1148         case INTERACT_DIGGING_COMPLETED: {
1149                 // Only digging of nodes
1150                 if (pointed.type != POINTEDTHING_NODE)
1151                         return;
1152                 bool pos_ok;
1153                 v3s16 p_under = pointed.node_undersurface;
1154                 MapNode n = m_env->getMap().getNode(p_under, &pos_ok);
1155                 if (!pos_ok) {
1156                         infostream << "Server: Not finishing digging: Node not found. "
1157                                 "Adding block to emerge queue." << std::endl;
1158                         m_emerge->enqueueBlockEmerge(peer_id,
1159                                 getNodeBlockPos(pointed.node_abovesurface), false);
1160                 }
1161
1162                 /* Cheat prevention */
1163                 bool is_valid_dig = true;
1164                 if (enable_anticheat && !isSingleplayer()) {
1165                         v3s16 nocheat_p = playersao->getNoCheatDigPos();
1166                         float nocheat_t = playersao->getNoCheatDigTime();
1167                         playersao->noCheatDigEnd();
1168                         // If player didn't start digging this, ignore dig
1169                         if (nocheat_p != p_under) {
1170                                 infostream << "Server: " << player->getName()
1171                                                 << " started digging "
1172                                                 << PP(nocheat_p) << " and completed digging "
1173                                                 << PP(p_under) << "; not digging." << std::endl;
1174                                 is_valid_dig = false;
1175                                 // Call callbacks
1176                                 m_script->on_cheat(playersao, "finished_unknown_dig");
1177                         }
1178
1179                         // Get player's wielded item
1180                         // See also: Game::handleDigging
1181                         ItemStack selected_item, hand_item;
1182                         playersao->getPlayer()->getWieldedItem(&selected_item, &hand_item);
1183
1184                         // Get diggability and expected digging time
1185                         DigParams params = getDigParams(m_nodedef->get(n).groups,
1186                                         &selected_item.getToolCapabilities(m_itemdef));
1187                         // If can't dig, try hand
1188                         if (!params.diggable) {
1189                                 params = getDigParams(m_nodedef->get(n).groups,
1190                                         &hand_item.getToolCapabilities(m_itemdef));
1191                         }
1192                         // If can't dig, ignore dig
1193                         if (!params.diggable) {
1194                                 infostream << "Server: " << player->getName()
1195                                                 << " completed digging " << PP(p_under)
1196                                                 << ", which is not diggable with tool; not digging."
1197                                                 << std::endl;
1198                                 is_valid_dig = false;
1199                                 // Call callbacks
1200                                 m_script->on_cheat(playersao, "dug_unbreakable");
1201                         }
1202                         // Check digging time
1203                         // If already invalidated, we don't have to
1204                         if (!is_valid_dig) {
1205                                 // Well not our problem then
1206                         }
1207                         // Clean and long dig
1208                         else if (params.time > 2.0 && nocheat_t * 1.2 > params.time) {
1209                                 // All is good, but grab time from pool; don't care if
1210                                 // it's actually available
1211                                 playersao->getDigPool().grab(params.time);
1212                         }
1213                         // Short or laggy dig
1214                         // Try getting the time from pool
1215                         else if (playersao->getDigPool().grab(params.time)) {
1216                                 // All is good
1217                         }
1218                         // Dig not possible
1219                         else {
1220                                 infostream << "Server: " << player->getName()
1221                                                 << " completed digging " << PP(p_under)
1222                                                 << "too fast; not digging." << std::endl;
1223                                 is_valid_dig = false;
1224                                 // Call callbacks
1225                                 m_script->on_cheat(playersao, "dug_too_fast");
1226                         }
1227                 }
1228
1229                 /* Actually dig node */
1230
1231                 if (is_valid_dig && n.getContent() != CONTENT_IGNORE)
1232                         m_script->node_on_dig(p_under, n, playersao);
1233
1234                 v3s16 blockpos = getNodeBlockPos(p_under);
1235                 RemoteClient *client = getClient(peer_id);
1236                 // Send unusual result (that is, node not being removed)
1237                 if (m_env->getMap().getNode(p_under).getContent() != CONTENT_AIR)
1238                         // Re-send block to revert change on client-side
1239                         client->SetBlockNotSent(blockpos);
1240                 else
1241                         client->ResendBlockIfOnWire(blockpos);
1242
1243                 return;
1244         } // action == INTERACT_DIGGING_COMPLETED
1245
1246         // Place block or right-click object
1247         case INTERACT_PLACE: {
1248                 ItemStack selected_item;
1249                 playersao->getWieldedItem(&selected_item, nullptr);
1250
1251                 // Reset build time counter
1252                 if (pointed.type == POINTEDTHING_NODE &&
1253                                 selected_item.getDefinition(m_itemdef).type == ITEM_NODE)
1254                         getClient(peer_id)->m_time_from_building = 0.0;
1255
1256                 if (pointed.type == POINTEDTHING_OBJECT) {
1257                         // Right click object
1258
1259                         // Skip if object can't be interacted with anymore
1260                         if (pointed_object->isGone())
1261                                 return;
1262
1263                         actionstream << player->getName() << " right-clicks object "
1264                                         << pointed.object_id << ": "
1265                                         << pointed_object->getDescription() << std::endl;
1266
1267                         // Do stuff
1268                         if (m_script->item_OnSecondaryUse(
1269                                         selected_item, playersao, pointed)) {
1270                                 if (playersao->setWieldedItem(selected_item)) {
1271                                         SendInventory(playersao, true);
1272                                 }
1273                         }
1274
1275                         pointed_object->rightClick(playersao);
1276                 } else if (m_script->item_OnPlace(selected_item, playersao, pointed)) {
1277                         // Placement was handled in lua
1278
1279                         // Apply returned ItemStack
1280                         if (playersao->setWieldedItem(selected_item))
1281                                 SendInventory(playersao, true);
1282                 }
1283
1284                 if (pointed.type != POINTEDTHING_NODE)
1285                         return;
1286
1287                 // If item has node placement prediction, always send the
1288                 // blocks to make sure the client knows what exactly happened
1289                 RemoteClient *client = getClient(peer_id);
1290                 v3s16 blockpos = getNodeBlockPos(pointed.node_abovesurface);
1291                 v3s16 blockpos2 = getNodeBlockPos(pointed.node_undersurface);
1292                 if (!selected_item.getDefinition(m_itemdef
1293                                 ).node_placement_prediction.empty()) {
1294                         client->SetBlockNotSent(blockpos);
1295                         if (blockpos2 != blockpos)
1296                                 client->SetBlockNotSent(blockpos2);
1297                 } else {
1298                         client->ResendBlockIfOnWire(blockpos);
1299                         if (blockpos2 != blockpos)
1300                                 client->ResendBlockIfOnWire(blockpos2);
1301                 }
1302
1303                 return;
1304         } // action == INTERACT_PLACE
1305
1306         case INTERACT_USE: {
1307                 ItemStack selected_item;
1308                 playersao->getWieldedItem(&selected_item, nullptr);
1309
1310                 actionstream << player->getName() << " uses " << selected_item.name
1311                                 << ", pointing at " << pointed.dump() << std::endl;
1312
1313                 if (m_script->item_OnUse(selected_item, playersao, pointed)) {
1314                         // Apply returned ItemStack
1315                         if (playersao->setWieldedItem(selected_item))
1316                                 SendInventory(playersao, true);
1317                 }
1318
1319                 return;
1320         }
1321
1322         // Rightclick air
1323         case INTERACT_ACTIVATE: {
1324                 ItemStack selected_item;
1325                 playersao->getWieldedItem(&selected_item, nullptr);
1326
1327                 actionstream << player->getName() << " activates "
1328                                 << selected_item.name << std::endl;
1329
1330                 pointed.type = POINTEDTHING_NOTHING; // can only ever be NOTHING
1331
1332                 if (m_script->item_OnSecondaryUse(selected_item, playersao, pointed)) {
1333                         if (playersao->setWieldedItem(selected_item))
1334                                 SendInventory(playersao, true);
1335                 }
1336
1337                 return;
1338         }
1339
1340         default:
1341                 warningstream << "Server: Invalid action " << action << std::endl;
1342
1343         }
1344 }
1345
1346 void Server::handleCommand_RemovedSounds(NetworkPacket* pkt)
1347 {
1348         u16 num;
1349         *pkt >> num;
1350         for (u16 k = 0; k < num; k++) {
1351                 s32 id;
1352
1353                 *pkt >> id;
1354
1355                 std::unordered_map<s32, ServerPlayingSound>::iterator i =
1356                         m_playing_sounds.find(id);
1357                 if (i == m_playing_sounds.end())
1358                         continue;
1359
1360                 ServerPlayingSound &psound = i->second;
1361                 psound.clients.erase(pkt->getPeerId());
1362                 if (psound.clients.empty())
1363                         m_playing_sounds.erase(i++);
1364         }
1365 }
1366
1367 void Server::handleCommand_NodeMetaFields(NetworkPacket* pkt)
1368 {
1369         v3s16 p;
1370         std::string formname;
1371         u16 num;
1372
1373         *pkt >> p >> formname >> num;
1374
1375         StringMap fields;
1376         for (u16 k = 0; k < num; k++) {
1377                 std::string fieldname;
1378                 *pkt >> fieldname;
1379                 fields[fieldname] = pkt->readLongString();
1380         }
1381
1382         session_t peer_id = pkt->getPeerId();
1383         RemotePlayer *player = m_env->getPlayer(peer_id);
1384
1385         if (player == NULL) {
1386                 errorstream <<
1387                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
1388                         peer_id << " disconnecting peer!" << std::endl;
1389                 DisconnectPeer(peer_id);
1390                 return;
1391         }
1392
1393         PlayerSAO *playersao = player->getPlayerSAO();
1394         if (playersao == NULL) {
1395                 errorstream <<
1396                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
1397                         peer_id << " disconnecting peer!" << std::endl;
1398                 DisconnectPeer(peer_id);
1399                 return;
1400         }
1401
1402         // If something goes wrong, this player is to blame
1403         RollbackScopeActor rollback_scope(m_rollback,
1404                         std::string("player:")+player->getName());
1405
1406         // Check the target node for rollback data; leave others unnoticed
1407         RollbackNode rn_old(&m_env->getMap(), p, this);
1408
1409         m_script->node_on_receive_fields(p, formname, fields, playersao);
1410
1411         // Report rollback data
1412         RollbackNode rn_new(&m_env->getMap(), p, this);
1413         if (rollback() && rn_new != rn_old) {
1414                 RollbackAction action;
1415                 action.setSetNode(p, rn_old, rn_new);
1416                 rollback()->reportAction(action);
1417         }
1418 }
1419
1420 void Server::handleCommand_InventoryFields(NetworkPacket* pkt)
1421 {
1422         std::string client_formspec_name;
1423         u16 num;
1424
1425         *pkt >> client_formspec_name >> num;
1426
1427         StringMap fields;
1428         for (u16 k = 0; k < num; k++) {
1429                 std::string fieldname;
1430                 *pkt >> fieldname;
1431                 fields[fieldname] = pkt->readLongString();
1432         }
1433
1434         session_t peer_id = pkt->getPeerId();
1435         RemotePlayer *player = m_env->getPlayer(peer_id);
1436
1437         if (player == NULL) {
1438                 errorstream <<
1439                         "Server::ProcessData(): Canceling: No player for peer_id=" <<
1440                         peer_id << " disconnecting peer!" << std::endl;
1441                 DisconnectPeer(peer_id);
1442                 return;
1443         }
1444
1445         PlayerSAO *playersao = player->getPlayerSAO();
1446         if (playersao == NULL) {
1447                 errorstream <<
1448                         "Server::ProcessData(): Canceling: No player object for peer_id=" <<
1449                         peer_id << " disconnecting peer!" << std::endl;
1450                 DisconnectPeer(peer_id);
1451                 return;
1452         }
1453
1454         if (client_formspec_name.empty()) { // pass through inventory submits
1455                 m_script->on_playerReceiveFields(playersao, client_formspec_name, fields);
1456                 return;
1457         }
1458
1459         // verify that we displayed the formspec to the user
1460         const auto peer_state_iterator = m_formspec_state_data.find(peer_id);
1461         if (peer_state_iterator != m_formspec_state_data.end()) {
1462                 const std::string &server_formspec_name = peer_state_iterator->second;
1463                 if (client_formspec_name == server_formspec_name) {
1464                         auto it = fields.find("quit");
1465                         if (it != fields.end() && it->second == "true")
1466                                 m_formspec_state_data.erase(peer_state_iterator);
1467
1468                         m_script->on_playerReceiveFields(playersao, client_formspec_name, fields);
1469                         return;
1470                 }
1471                 actionstream << "'" << player->getName()
1472                         << "' submitted formspec ('" << client_formspec_name
1473                         << "') but the name of the formspec doesn't match the"
1474                         " expected name ('" << server_formspec_name << "')";
1475
1476         } else {
1477                 actionstream << "'" << player->getName()
1478                         << "' submitted formspec ('" << client_formspec_name
1479                         << "') but server hasn't sent formspec to client";
1480         }
1481         actionstream << ", possible exploitation attempt" << std::endl;
1482 }
1483
1484 void Server::handleCommand_FirstSrp(NetworkPacket* pkt)
1485 {
1486         session_t peer_id = pkt->getPeerId();
1487         RemoteClient *client = getClient(peer_id, CS_Invalid);
1488         ClientState cstate = client->getState();
1489
1490         std::string playername = client->getName();
1491
1492         std::string salt;
1493         std::string verification_key;
1494
1495         std::string addr_s = getPeerAddress(peer_id).serializeString();
1496         u8 is_empty;
1497
1498         *pkt >> salt >> verification_key >> is_empty;
1499
1500         verbosestream << "Server: Got TOSERVER_FIRST_SRP from " << addr_s
1501                 << ", with is_empty=" << (is_empty == 1) << std::endl;
1502
1503         // Either this packet is sent because the user is new or to change the password
1504         if (cstate == CS_HelloSent) {
1505                 if (!client->isMechAllowed(AUTH_MECHANISM_FIRST_SRP)) {
1506                         actionstream << "Server: Client from " << addr_s
1507                                         << " tried to set password without being "
1508                                         << "authenticated, or the username being new." << std::endl;
1509                         DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1510                         return;
1511                 }
1512
1513                 if (!isSingleplayer() &&
1514                                 g_settings->getBool("disallow_empty_password") &&
1515                                 is_empty == 1) {
1516                         actionstream << "Server: " << playername
1517                                         << " supplied empty password from " << addr_s << std::endl;
1518                         DenyAccess(peer_id, SERVER_ACCESSDENIED_EMPTY_PASSWORD);
1519                         return;
1520                 }
1521
1522                 std::string initial_ver_key;
1523
1524                 initial_ver_key = encode_srp_verifier(verification_key, salt);
1525                 m_script->createAuth(playername, initial_ver_key);
1526                 m_script->on_authplayer(playername, addr_s, true);
1527
1528                 acceptAuth(peer_id, false);
1529         } else {
1530                 if (cstate < CS_SudoMode) {
1531                         infostream << "Server::ProcessData(): Ignoring TOSERVER_FIRST_SRP from "
1532                                         << addr_s << ": " << "Client has wrong state " << cstate << "."
1533                                         << std::endl;
1534                         return;
1535                 }
1536                 m_clients.event(peer_id, CSE_SudoLeave);
1537                 std::string pw_db_field = encode_srp_verifier(verification_key, salt);
1538                 bool success = m_script->setPassword(playername, pw_db_field);
1539                 if (success) {
1540                         actionstream << playername << " changes password" << std::endl;
1541                         SendChatMessage(peer_id, ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
1542                                 L"Password change successful."));
1543                 } else {
1544                         actionstream << playername <<
1545                                 " tries to change password but it fails" << std::endl;
1546                         SendChatMessage(peer_id, ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
1547                                 L"Password change failed or unavailable."));
1548                 }
1549         }
1550 }
1551
1552 void Server::handleCommand_SrpBytesA(NetworkPacket* pkt)
1553 {
1554         session_t peer_id = pkt->getPeerId();
1555         RemoteClient *client = getClient(peer_id, CS_Invalid);
1556         ClientState cstate = client->getState();
1557
1558         bool wantSudo = (cstate == CS_Active);
1559
1560         if (!((cstate == CS_HelloSent) || (cstate == CS_Active))) {
1561                 actionstream << "Server: got SRP _A packet in wrong state " << cstate <<
1562                         " from " << getPeerAddress(peer_id).serializeString() <<
1563                         ". Ignoring." << std::endl;
1564                 return;
1565         }
1566
1567         if (client->chosen_mech != AUTH_MECHANISM_NONE) {
1568                 actionstream << "Server: got SRP _A packet, while auth is already "
1569                         "going on with mech " << client->chosen_mech << " from " <<
1570                         getPeerAddress(peer_id).serializeString() <<
1571                         " (wantSudo=" << wantSudo << "). Ignoring." << std::endl;
1572                 if (wantSudo) {
1573                         DenySudoAccess(peer_id);
1574                         return;
1575                 }
1576
1577                 DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1578                 return;
1579         }
1580
1581         std::string bytes_A;
1582         u8 based_on;
1583         *pkt >> bytes_A >> based_on;
1584
1585         infostream << "Server: TOSERVER_SRP_BYTES_A received with "
1586                 << "based_on=" << int(based_on) << " and len_A="
1587                 << bytes_A.length() << "." << std::endl;
1588
1589         AuthMechanism chosen = (based_on == 0) ?
1590                 AUTH_MECHANISM_LEGACY_PASSWORD : AUTH_MECHANISM_SRP;
1591
1592         if (wantSudo) {
1593                 if (!client->isSudoMechAllowed(chosen)) {
1594                         actionstream << "Server: Player \"" << client->getName() <<
1595                                 "\" at " << getPeerAddress(peer_id).serializeString() <<
1596                                 " tried to change password using unallowed mech " << chosen <<
1597                                 "." << std::endl;
1598                         DenySudoAccess(peer_id);
1599                         return;
1600                 }
1601         } else {
1602                 if (!client->isMechAllowed(chosen)) {
1603                         actionstream << "Server: Client tried to authenticate from " <<
1604                                 getPeerAddress(peer_id).serializeString() <<
1605                                 " using unallowed mech " << chosen << "." << std::endl;
1606                         DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1607                         return;
1608                 }
1609         }
1610
1611         client->chosen_mech = chosen;
1612
1613         std::string salt;
1614         std::string verifier;
1615
1616         if (based_on == 0) {
1617
1618                 generate_srp_verifier_and_salt(client->getName(), client->enc_pwd,
1619                         &verifier, &salt);
1620         } else if (!decode_srp_verifier_and_salt(client->enc_pwd, &verifier, &salt)) {
1621                 // Non-base64 errors should have been catched in the init handler
1622                 actionstream << "Server: User " << client->getName() <<
1623                         " tried to log in, but srp verifier field was invalid (most likely "
1624                         "invalid base64)." << std::endl;
1625                 DenyAccess(peer_id, SERVER_ACCESSDENIED_SERVER_FAIL);
1626                 return;
1627         }
1628
1629         char *bytes_B = 0;
1630         size_t len_B = 0;
1631
1632         client->auth_data = srp_verifier_new(SRP_SHA256, SRP_NG_2048,
1633                 client->getName().c_str(),
1634                 (const unsigned char *) salt.c_str(), salt.size(),
1635                 (const unsigned char *) verifier.c_str(), verifier.size(),
1636                 (const unsigned char *) bytes_A.c_str(), bytes_A.size(),
1637                 NULL, 0,
1638                 (unsigned char **) &bytes_B, &len_B, NULL, NULL);
1639
1640         if (!bytes_B) {
1641                 actionstream << "Server: User " << client->getName()
1642                         << " tried to log in, SRP-6a safety check violated in _A handler."
1643                         << std::endl;
1644                 if (wantSudo) {
1645                         DenySudoAccess(peer_id);
1646                         return;
1647                 }
1648
1649                 DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1650                 return;
1651         }
1652
1653         NetworkPacket resp_pkt(TOCLIENT_SRP_BYTES_S_B, 0, peer_id);
1654         resp_pkt << salt << std::string(bytes_B, len_B);
1655         Send(&resp_pkt);
1656 }
1657
1658 void Server::handleCommand_SrpBytesM(NetworkPacket* pkt)
1659 {
1660         session_t peer_id = pkt->getPeerId();
1661         RemoteClient *client = getClient(peer_id, CS_Invalid);
1662         ClientState cstate = client->getState();
1663         std::string addr_s = getPeerAddress(pkt->getPeerId()).serializeString();
1664         std::string playername = client->getName();
1665
1666         bool wantSudo = (cstate == CS_Active);
1667
1668         verbosestream << "Server: Received TOCLIENT_SRP_BYTES_M." << std::endl;
1669
1670         if (!((cstate == CS_HelloSent) || (cstate == CS_Active))) {
1671                 actionstream << "Server: got SRP _M packet in wrong state "
1672                         << cstate << " from " << addr_s
1673                         << ". Ignoring." << std::endl;
1674                 return;
1675         }
1676
1677         if (client->chosen_mech != AUTH_MECHANISM_SRP &&
1678                         client->chosen_mech != AUTH_MECHANISM_LEGACY_PASSWORD) {
1679                 actionstream << "Server: got SRP _M packet, while auth"
1680                         << "is going on with mech " << client->chosen_mech << " from "
1681                         << addr_s << " (wantSudo=" << wantSudo << "). Denying." << std::endl;
1682                 if (wantSudo) {
1683                         DenySudoAccess(peer_id);
1684                         return;
1685                 }
1686
1687                 DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1688                 return;
1689         }
1690
1691         std::string bytes_M;
1692         *pkt >> bytes_M;
1693
1694         if (srp_verifier_get_session_key_length((SRPVerifier *) client->auth_data)
1695                         != bytes_M.size()) {
1696                 actionstream << "Server: User " << playername << " at " << addr_s
1697                         << " sent bytes_M with invalid length " << bytes_M.size() << std::endl;
1698                 DenyAccess(peer_id, SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1699                 return;
1700         }
1701
1702         unsigned char *bytes_HAMK = 0;
1703
1704         srp_verifier_verify_session((SRPVerifier *) client->auth_data,
1705                 (unsigned char *)bytes_M.c_str(), &bytes_HAMK);
1706
1707         if (!bytes_HAMK) {
1708                 if (wantSudo) {
1709                         actionstream << "Server: User " << playername << " at " << addr_s
1710                                 << " tried to change their password, but supplied wrong"
1711                                 << " (SRP) password for authentication." << std::endl;
1712                         DenySudoAccess(peer_id);
1713                         return;
1714                 }
1715
1716                 actionstream << "Server: User " << playername << " at " << addr_s
1717                         << " supplied wrong password (auth mechanism: SRP)." << std::endl;
1718                 m_script->on_authplayer(playername, addr_s, false);
1719                 DenyAccess(peer_id, SERVER_ACCESSDENIED_WRONG_PASSWORD);
1720                 return;
1721         }
1722
1723         if (client->create_player_on_auth_success) {
1724                 m_script->createAuth(playername, client->enc_pwd);
1725
1726                 std::string checkpwd; // not used, but needed for passing something
1727                 if (!m_script->getAuth(playername, &checkpwd, NULL)) {
1728                         actionstream << "Server: " << playername <<
1729                                 " cannot be authenticated (auth handler does not work?)" <<
1730                                 std::endl;
1731                         DenyAccess(peer_id, SERVER_ACCESSDENIED_SERVER_FAIL);
1732                         return;
1733                 }
1734                 client->create_player_on_auth_success = false;
1735         }
1736
1737         m_script->on_authplayer(playername, addr_s, true);
1738         acceptAuth(peer_id, wantSudo);
1739 }
1740
1741 /*
1742  * Mod channels
1743  */
1744
1745 void Server::handleCommand_ModChannelJoin(NetworkPacket *pkt)
1746 {
1747         std::string channel_name;
1748         *pkt >> channel_name;
1749
1750         session_t peer_id = pkt->getPeerId();
1751         NetworkPacket resp_pkt(TOCLIENT_MODCHANNEL_SIGNAL,
1752                 1 + 2 + channel_name.size(), peer_id);
1753
1754         // Send signal to client to notify join succeed or not
1755         if (g_settings->getBool("enable_mod_channels") &&
1756                         m_modchannel_mgr->joinChannel(channel_name, peer_id)) {
1757                 resp_pkt << (u8) MODCHANNEL_SIGNAL_JOIN_OK;
1758                 infostream << "Peer " << peer_id << " joined channel " <<
1759                         channel_name << std::endl;
1760         }
1761         else {
1762                 resp_pkt << (u8)MODCHANNEL_SIGNAL_JOIN_FAILURE;
1763                 infostream << "Peer " << peer_id << " tried to join channel " <<
1764                         channel_name << ", but was already registered." << std::endl;
1765         }
1766         resp_pkt << channel_name;
1767         Send(&resp_pkt);
1768 }
1769
1770 void Server::handleCommand_ModChannelLeave(NetworkPacket *pkt)
1771 {
1772         std::string channel_name;
1773         *pkt >> channel_name;
1774
1775         session_t peer_id = pkt->getPeerId();
1776         NetworkPacket resp_pkt(TOCLIENT_MODCHANNEL_SIGNAL,
1777                 1 + 2 + channel_name.size(), peer_id);
1778
1779         // Send signal to client to notify join succeed or not
1780         if (g_settings->getBool("enable_mod_channels") &&
1781                         m_modchannel_mgr->leaveChannel(channel_name, peer_id)) {
1782                 resp_pkt << (u8)MODCHANNEL_SIGNAL_LEAVE_OK;
1783                 infostream << "Peer " << peer_id << " left channel " << channel_name <<
1784                         std::endl;
1785         } else {
1786                 resp_pkt << (u8) MODCHANNEL_SIGNAL_LEAVE_FAILURE;
1787                 infostream << "Peer " << peer_id << " left channel " << channel_name <<
1788                         ", but was not registered." << std::endl;
1789         }
1790         resp_pkt << channel_name;
1791         Send(&resp_pkt);
1792 }
1793
1794 void Server::handleCommand_ModChannelMsg(NetworkPacket *pkt)
1795 {
1796         std::string channel_name, channel_msg;
1797         *pkt >> channel_name >> channel_msg;
1798
1799         session_t peer_id = pkt->getPeerId();
1800         verbosestream << "Mod channel message received from peer " << peer_id <<
1801                 " on channel " << channel_name << " message: " << channel_msg <<
1802                 std::endl;
1803
1804         // If mod channels are not enabled, discard message
1805         if (!g_settings->getBool("enable_mod_channels")) {
1806                 return;
1807         }
1808
1809         // If channel not registered, signal it and ignore message
1810         if (!m_modchannel_mgr->channelRegistered(channel_name)) {
1811                 NetworkPacket resp_pkt(TOCLIENT_MODCHANNEL_SIGNAL,
1812                         1 + 2 + channel_name.size(), peer_id);
1813                 resp_pkt << (u8)MODCHANNEL_SIGNAL_CHANNEL_NOT_REGISTERED << channel_name;
1814                 Send(&resp_pkt);
1815                 return;
1816         }
1817
1818         // @TODO: filter, rate limit
1819
1820         broadcastModChannelMessage(channel_name, channel_msg, peer_id);
1821 }