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 "content_sao.h"
  24 #include "emerge.h"
  25 #include "mapblock.h"
  26 #include "modchannels.h"
  27 #include "nodedef.h"
  28 #include "remoteplayer.h"
  29 #include "rollback_interface.h"
  30 #include "scripting_server.h"
  31 #include "settings.h"
  32 #include "tool.h"
  33 #include "version.h"
  34 #include "network/connection.h"
  35 #include "network/networkprotocol.h"
  36 #include "network/serveropcodes.h"
  37 #include "util/auth.h"
  38 #include "util/base64.h"
  39 #include "util/pointedthing.h"
  40 #include "util/serialize.h"
  41 #include "util/srp.h"
  42
  43 void Server::handleCommand_Deprecated(NetworkPacket* pkt)
  44 {
  45         infostream << "Server: " << toServerCommandTable[pkt->getCommand()].name
  46                 << " not supported anymore" << std::endl;
  47 }
  48
  49 void Server::handleCommand_Init(NetworkPacket* pkt)
  50 {
  51
  52         if(pkt->getSize() < 1)
  53                 return;
  54
  55         RemoteClient* client = getClient(pkt->getPeerId(), CS_Created);
  56
  57         std::string addr_s;
  58         try {
  59                 Address address = getPeerAddress(pkt->getPeerId());
  60                 addr_s = address.serializeString();
  61         }
  62         catch (con::PeerNotFoundException &e) {
  63                 /*
  64                  * no peer for this packet found
  65                  * most common reason is peer timeout, e.g. peer didn't
  66                  * respond for some time, your server was overloaded or
  67                  * things like that.
  68                  */
  69                 infostream << "Server::ProcessData(): Canceling: peer "
  70                                 << pkt->getPeerId() << " not found" << std::endl;
  71                 return;
  72         }
  73
  74         // If net_proto_version is set, this client has already been handled
  75         if (client->getState() > CS_Created) {
  76                 verbosestream << "Server: Ignoring multiple TOSERVER_INITs from "
  77                                 << addr_s << " (peer_id=" << pkt->getPeerId() << ")" << std::endl;
  78                 return;
  79         }
  80
  81         verbosestream << "Server: Got TOSERVER_INIT from " << addr_s << " (peer_id="
  82                         << pkt->getPeerId() << ")" << std::endl;
  83
  84         // Do not allow multiple players in simple singleplayer mode.
  85         // This isn't a perfect way to do it, but will suffice for now
  86         if (m_simple_singleplayer_mode && m_clients.getClientIDs().size() > 1) {
  87                 infostream << "Server: Not allowing another client (" << addr_s
  88                                 << ") to connect in simple singleplayer mode" << std::endl;
  89                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_SINGLEPLAYER);
  90                 return;
  91         }
  92
  93         // First byte after command is maximum supported
  94         // serialization version
  95         u8 client_max;
  96         u16 supp_compr_modes;
  97         u16 min_net_proto_version = 0;
  98         u16 max_net_proto_version;
  99         std::string playerName;
 100
 101         *pkt >> client_max >> supp_compr_modes >> min_net_proto_version
 102                         >> max_net_proto_version >> playerName;
 103
 104         u8 our_max = SER_FMT_VER_HIGHEST_READ;
 105         // Use the highest version supported by both
 106         u8 depl_serial_v = std::min(client_max, our_max);
 107         // If it's lower than the lowest supported, give up.
 108         if (depl_serial_v < SER_FMT_VER_LOWEST_READ)
 109                 depl_serial_v = SER_FMT_VER_INVALID;
 110
 111         if (depl_serial_v == SER_FMT_VER_INVALID) {
 112                 actionstream << "Server: A mismatched client tried to connect from "
 113                                 << addr_s << std::endl;
 114                 infostream<<"Server: Cannot negotiate serialization version with "
 115                                 << addr_s << std::endl;
 116                 DenyAccess(pkt->getPeerId(), 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 < SERVER_PROTOCOL_VERSION_MIN ||
 147                         net_proto_version > SERVER_PROTOCOL_VERSION_MAX) {
 148                 actionstream << "Server: A mismatched client tried to connect from "
 149                                 << addr_s << std::endl;
 150                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_VERSION);
 151                 return;
 152         }
 153
 154         /*
 155                 Validate player name
 156         */
 157         const char* playername = playerName.c_str();
 158
 159         size_t pns = playerName.size();
 160         if (pns == 0 || pns > PLAYERNAME_SIZE) {
 161                 actionstream << "Server: Player with "
 162                         << ((pns > PLAYERNAME_SIZE) ? "a too long" : "an empty")
 163                         << " name tried to connect from " << addr_s << std::endl;
 164                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_NAME);
 165                 return;
 166         }
 167
 168         if (!string_allowed(playerName, PLAYERNAME_ALLOWED_CHARS)) {
 169                 actionstream << "Server: Player with an invalid name "
 170                                 << "tried to connect from " << addr_s << std::endl;
 171                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_CHARS_IN_NAME);
 172                 return;
 173         }
 174
 175         m_clients.setPlayerName(pkt->getPeerId(), playername);
 176         //TODO (later) case insensitivity
 177
 178         std::string legacyPlayerNameCasing = playerName;
 179
 180         if (!isSingleplayer() && strcasecmp(playername, "singleplayer") == 0) {
 181                 actionstream << "Server: Player with the name \"singleplayer\" "
 182                                 << "tried to connect from " << addr_s << std::endl;
 183                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_NAME);
 184                 return;
 185         }
 186
 187         {
 188                 std::string reason;
 189                 if (m_script->on_prejoinplayer(playername, addr_s, &reason)) {
 190                         actionstream << "Server: Player with the name \"" << playerName << "\" "
 191                                         << "tried to connect from " << addr_s << " "
 192                                         << "but it was disallowed for the following reason: "
 193                                         << reason << std::endl;
 194                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_CUSTOM_STRING, reason);
 195                         return;
 196                 }
 197         }
 198
 199         infostream << "Server: New connection: \"" << playerName << "\" from "
 200                         << addr_s << " (peer_id=" << pkt->getPeerId() << ")" << std::endl;
 201
 202         // Enforce user limit.
 203         // Don't enforce for users that have some admin right or mod permits it.
 204         if (m_clients.isUserLimitReached() &&
 205                         playername != g_settings->get("name") &&
 206                         !m_script->can_bypass_userlimit(playername, addr_s)) {
 207                 actionstream << "Server: " << playername << " tried to join from "
 208                                 << addr_s << ", but there" << " are already max_users="
 209                                 << g_settings->getU16("max_users") << " players." << std::endl;
 210                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_TOO_MANY_USERS);
 211                 return;
 212         }
 213
 214         /*
 215                 Compose auth methods for answer
 216         */
 217         std::string encpwd; // encrypted Password field for the user
 218         bool has_auth = m_script->getAuth(playername, &encpwd, NULL);
 219         u32 auth_mechs = 0;
 220
 221         client->chosen_mech = AUTH_MECHANISM_NONE;
 222
 223         if (has_auth) {
 224                 std::vector<std::string> pwd_components = str_split(encpwd, '#');
 225                 if (pwd_components.size() == 4) {
 226                         if (pwd_components[1] == "1") { // 1 means srp
 227                                 auth_mechs |= AUTH_MECHANISM_SRP;
 228                                 client->enc_pwd = encpwd;
 229                         } else {
 230                                 actionstream << "User " << playername
 231                                         << " tried to log in, but password field"
 232                                         << " was invalid (unknown mechcode)." << std::endl;
 233                                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_SERVER_FAIL);
 234                                 return;
 235                         }
 236                 } else if (base64_is_valid(encpwd)) {
 237                         auth_mechs |= AUTH_MECHANISM_LEGACY_PASSWORD;
 238                         client->enc_pwd = encpwd;
 239                 } else {
 240                         actionstream << "User " << playername
 241                                 << " tried to log in, but password field"
 242                                 << " was invalid (invalid base64)." << std::endl;
 243                         DenyAccess(pkt->getPeerId(), 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, 1 + 4
 267                 + legacyPlayerNameCasing.size(), pkt->getPeerId());
 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(pkt->getPeerId(), CSE_Hello);
 279 }
 280
 281 void Server::handleCommand_Init2(NetworkPacket* pkt)
 282 {
 283         verbosestream << "Server: Got TOSERVER_INIT2 from "
 284                         << pkt->getPeerId() << std::endl;
 285
 286         m_clients.event(pkt->getPeerId(), CSE_GotInit2);
 287         u16 protocol_version = m_clients.getProtocolVersion(pkt->getPeerId());
 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 "
 298                         << getPlayerName(pkt->getPeerId()) << std::endl;
 299
 300         // Send player movement settings
 301         SendMovement(pkt->getPeerId());
 302
 303         // Send item definitions
 304         SendItemDef(pkt->getPeerId(), m_itemdef, protocol_version);
 305
 306         // Send node definitions
 307         SendNodeDef(pkt->getPeerId(), m_nodedef, protocol_version);
 308
 309         m_clients.event(pkt->getPeerId(), CSE_SetDefinitionsSent);
 310
 311         // Send media announcement
 312         sendMediaAnnouncement(pkt->getPeerId(), lang);
 313
 314         // Send detached inventories
 315         sendDetachedInventories(pkt->getPeerId());
 316
 317         // Send time of day
 318         u16 time = m_env->getTimeOfDay();
 319         float time_speed = g_settings->getFloat("time_speed");
 320         SendTimeOfDay(pkt->getPeerId(), time, time_speed);
 321
 322         SendCSMFlavourLimits(pkt->getPeerId());
 323
 324         // Warnings about protocol version can be issued here
 325         if (getClient(pkt->getPeerId())->net_proto_version < LATEST_PROTOCOL_VERSION) {
 326                 SendChatMessage(pkt->getPeerId(), ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
 327                                 L"# Server: WARNING: YOUR CLIENT'S VERSION MAY NOT BE FULLY COMPATIBLE "
 328                                 L"WITH THIS SERVER!"));
 329
 330         }
 331 }
 332
 333 void Server::handleCommand_RequestMedia(NetworkPacket* pkt)
 334 {
 335         std::vector<std::string> tosend;
 336         u16 numfiles;
 337
 338         *pkt >> numfiles;
 339
 340         infostream << "Sending " << numfiles << " files to "
 341                         << getPlayerName(pkt->getPeerId()) << std::endl;
 342         verbosestream << "TOSERVER_REQUEST_MEDIA: " << std::endl;
 343
 344         for (u16 i = 0; i < numfiles; i++) {
 345                 std::string name;
 346
 347                 *pkt >> name;
 348
 349                 tosend.push_back(name);
 350                 verbosestream << "TOSERVER_REQUEST_MEDIA: requested file "
 351                                 << name << std::endl;
 352         }
 353
 354         sendRequestedMedia(pkt->getPeerId(), tosend);
 355 }
 356
 357 void Server::handleCommand_ClientReady(NetworkPacket* pkt)
 358 {
 359         session_t peer_id = pkt->getPeerId();
 360
 361         PlayerSAO* playersao = StageTwoClientInit(peer_id);
 362
 363         if (playersao == NULL) {
 364                 actionstream
 365                         << "TOSERVER_CLIENT_READY stage 2 client init failed for peer_id: "
 366                         << peer_id << std::endl;
 367                 DisconnectPeer(peer_id);
 368                 return;
 369         }
 370
 371
 372         if (pkt->getSize() < 8) {
 373                 errorstream
 374                         << "TOSERVER_CLIENT_READY client sent inconsistent data, disconnecting peer_id: "
 375                         << peer_id << std::endl;
 376                 DisconnectPeer(peer_id);
 377                 return;
 378         }
 379
 380         u8 major_ver, minor_ver, patch_ver, reserved;
 381         std::string full_ver;
 382         *pkt >> major_ver >> minor_ver >> patch_ver >> reserved >> full_ver;
 383
 384         m_clients.setClientVersion(
 385                         peer_id, major_ver, minor_ver, patch_ver,
 386                         full_ver);
 387
 388         const std::vector<std::string> &players = m_clients.getPlayerNames();
 389         NetworkPacket list_pkt(TOCLIENT_UPDATE_PLAYER_LIST, 0, peer_id);
 390         list_pkt << (u8) PLAYER_LIST_INIT << (u16) players.size();
 391         for (const std::string &player: players) {
 392                 list_pkt <<  player;
 393         }
 394         m_clients.send(peer_id, 0, &list_pkt, true);
 395
 396         NetworkPacket notice_pkt(TOCLIENT_UPDATE_PLAYER_LIST, 0, PEER_ID_INEXISTENT);
 397         // (u16) 1 + std::string represents a pseudo vector serialization representation
 398         notice_pkt << (u8) PLAYER_LIST_ADD << (u16) 1 << std::string(playersao->getPlayer()->getName());
 399         m_clients.sendToAll(&notice_pkt);
 400
 401         m_clients.event(peer_id, CSE_SetClientReady);
 402         m_script->on_joinplayer(playersao);
 403         // Send shutdown timer if shutdown has been scheduled
 404         if (m_shutdown_timer > 0.0f) {
 405                 std::wstringstream ws;
 406                 ws << L"*** Server shutting down in "
 407                                 << duration_to_string(myround(m_shutdown_timer)).c_str() << ".";
 408                 SendChatMessage(pkt->getPeerId(), ws.str());
 409         }
 410 }
 411
 412 void Server::handleCommand_GotBlocks(NetworkPacket* pkt)
 413 {
 414         if (pkt->getSize() < 1)
 415                 return;
 416
 417         /*
 418                 [0] u16 command
 419                 [2] u8 count
 420                 [3] v3s16 pos_0
 421                 [3+6] v3s16 pos_1
 422                 ...
 423         */
 424
 425         u8 count;
 426         *pkt >> count;
 427
 428         RemoteClient *client = getClient(pkt->getPeerId());
 429
 430         if ((s16)pkt->getSize() < 1 + (int)count * 6) {
 431                 throw con::InvalidIncomingDataException
 432                                 ("GOTBLOCKS length is too short");
 433         }
 434
 435         for (u16 i = 0; i < count; i++) {
 436                 v3s16 p;
 437                 *pkt >> p;
 438                 client->GotBlock(p);
 439         }
 440 }
 441
 442 void Server::process_PlayerPos(RemotePlayer *player, PlayerSAO *playersao,
 443         NetworkPacket *pkt)
 444 {
 445         if (pkt->getRemainingBytes() < 12 + 12 + 4 + 4 + 4 + 1 + 1)
 446                 return;
 447
 448         v3s32 ps, ss;
 449         s32 f32pitch, f32yaw;
 450         u8 f32fov;
 451
 452         *pkt >> ps;
 453         *pkt >> ss;
 454         *pkt >> f32pitch;
 455         *pkt >> f32yaw;
 456
 457         f32 pitch = (f32)f32pitch / 100.0f;
 458         f32 yaw = (f32)f32yaw / 100.0f;
 459         u32 keyPressed = 0;
 460
 461         // default behavior (in case an old client doesn't send these)
 462         f32 fov = 0;
 463         u8 wanted_range = 0;
 464
 465         *pkt >> keyPressed;
 466         *pkt >> f32fov;
 467         fov = (f32)f32fov / 80.0f;
 468         *pkt >> wanted_range;
 469
 470         v3f position((f32)ps.X / 100.0f, (f32)ps.Y / 100.0f, (f32)ps.Z / 100.0f);
 471         v3f speed((f32)ss.X / 100.0f, (f32)ss.Y / 100.0f, (f32)ss.Z / 100.0f);
 472
 473         pitch = modulo360f(pitch);
 474         yaw = wrapDegrees_0_360(yaw);
 475
 476         playersao->setBasePosition(position);
 477         player->setSpeed(speed);
 478         playersao->setPitch(pitch);
 479         playersao->setYaw(yaw);
 480         playersao->setFov(fov);
 481         playersao->setWantedRange(wanted_range);
 482         player->keyPressed = keyPressed;
 483         player->control.up = (keyPressed & 1);
 484         player->control.down = (keyPressed & 2);
 485         player->control.left = (keyPressed & 4);
 486         player->control.right = (keyPressed & 8);
 487         player->control.jump = (keyPressed & 16);
 488         player->control.aux1 = (keyPressed & 32);
 489         player->control.sneak = (keyPressed & 64);
 490         player->control.LMB = (keyPressed & 128);
 491         player->control.RMB = (keyPressed & 256);
 492
 493         if (playersao->checkMovementCheat()) {
 494                 // Call callbacks
 495                 m_script->on_cheat(playersao, "moved_too_fast");
 496                 SendMovePlayer(pkt->getPeerId());
 497         }
 498 }
 499
 500 void Server::handleCommand_PlayerPos(NetworkPacket* pkt)
 501 {
 502         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
 503         if (player == NULL) {
 504                 errorstream << "Server::ProcessData(): Canceling: "
 505                                 "No player for peer_id=" << pkt->getPeerId()
 506                                 << " disconnecting peer!" << std::endl;
 507                 DisconnectPeer(pkt->getPeerId());
 508                 return;
 509         }
 510
 511         PlayerSAO *playersao = player->getPlayerSAO();
 512         if (playersao == NULL) {
 513                 errorstream << "Server::ProcessData(): Canceling: "
 514                                 "No player object for peer_id=" << pkt->getPeerId()
 515                                 << " disconnecting peer!" << std::endl;
 516                 DisconnectPeer(pkt->getPeerId());
 517                 return;
 518         }
 519
 520         // If player is dead we don't care of this packet
 521         if (playersao->isDead()) {
 522                 verbosestream << "TOSERVER_PLAYERPOS: " << player->getName()
 523                                 << " is dead. Ignoring packet";
 524                 return;
 525         }
 526
 527         process_PlayerPos(player, playersao, pkt);
 528 }
 529
 530 void Server::handleCommand_DeletedBlocks(NetworkPacket* pkt)
 531 {
 532         if (pkt->getSize() < 1)
 533                 return;
 534
 535         /*
 536                 [0] u16 command
 537                 [2] u8 count
 538                 [3] v3s16 pos_0
 539                 [3+6] v3s16 pos_1
 540                 ...
 541         */
 542
 543         u8 count;
 544         *pkt >> count;
 545
 546         RemoteClient *client = getClient(pkt->getPeerId());
 547
 548         if ((s16)pkt->getSize() < 1 + (int)count * 6) {
 549                 throw con::InvalidIncomingDataException
 550                                 ("DELETEDBLOCKS length is too short");
 551         }
 552
 553         for (u16 i = 0; i < count; i++) {
 554                 v3s16 p;
 555                 *pkt >> p;
 556                 client->SetBlockNotSent(p);
 557         }
 558 }
 559
 560 void Server::handleCommand_InventoryAction(NetworkPacket* pkt)
 561 {
 562         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
 563
 564         if (player == NULL) {
 565                 errorstream << "Server::ProcessData(): Canceling: "
 566                                 "No player for peer_id=" << pkt->getPeerId()
 567                                 << " disconnecting peer!" << std::endl;
 568                 DisconnectPeer(pkt->getPeerId());
 569                 return;
 570         }
 571
 572         PlayerSAO *playersao = player->getPlayerSAO();
 573         if (playersao == NULL) {
 574                 errorstream << "Server::ProcessData(): Canceling: "
 575                                 "No player object for peer_id=" << pkt->getPeerId()
 576                                 << " disconnecting peer!" << std::endl;
 577                 DisconnectPeer(pkt->getPeerId());
 578                 return;
 579         }
 580
 581         // Strip command and create a stream
 582         std::string datastring(pkt->getString(0), pkt->getSize());
 583         verbosestream << "TOSERVER_INVENTORY_ACTION: data=" << datastring
 584                 << std::endl;
 585         std::istringstream is(datastring, std::ios_base::binary);
 586         // Create an action
 587         InventoryAction *a = InventoryAction::deSerialize(is);
 588         if (!a) {
 589                 infostream << "TOSERVER_INVENTORY_ACTION: "
 590                                 << "InventoryAction::deSerialize() returned NULL"
 591                                 << std::endl;
 592                 return;
 593         }
 594
 595         // If something goes wrong, this player is to blame
 596         RollbackScopeActor rollback_scope(m_rollback,
 597                         std::string("player:")+player->getName());
 598
 599         /*
 600                 Note: Always set inventory not sent, to repair cases
 601                 where the client made a bad prediction.
 602         */
 603
 604         /*
 605                 Handle restrictions and special cases of the move action
 606         */
 607         if (a->getType() == IAction::Move) {
 608                 IMoveAction *ma = (IMoveAction*)a;
 609
 610                 ma->from_inv.applyCurrentPlayer(player->getName());
 611                 ma->to_inv.applyCurrentPlayer(player->getName());
 612
 613                 setInventoryModified(ma->from_inv, false);
 614                 setInventoryModified(ma->to_inv, false);
 615
 616                 bool from_inv_is_current_player =
 617                         (ma->from_inv.type == InventoryLocation::PLAYER) &&
 618                         (ma->from_inv.name == player->getName());
 619
 620                 bool to_inv_is_current_player =
 621                         (ma->to_inv.type == InventoryLocation::PLAYER) &&
 622                         (ma->to_inv.name == player->getName());
 623
 624                 /*
 625                         Disable moving items out of craftpreview
 626                 */
 627                 if (ma->from_list == "craftpreview") {
 628                         infostream << "Ignoring IMoveAction from "
 629                                         << (ma->from_inv.dump()) << ":" << ma->from_list
 630                                         << " to " << (ma->to_inv.dump()) << ":" << ma->to_list
 631                                         << " because src is " << ma->from_list << std::endl;
 632                         delete a;
 633                         return;
 634                 }
 635
 636                 /*
 637                         Disable moving items into craftresult and craftpreview
 638                 */
 639                 if (ma->to_list == "craftpreview" || ma->to_list == "craftresult") {
 640                         infostream << "Ignoring IMoveAction from "
 641                                         << (ma->from_inv.dump()) << ":" << ma->from_list
 642                                         << " to " << (ma->to_inv.dump()) << ":" << ma->to_list
 643                                         << " because dst is " << ma->to_list << std::endl;
 644                         delete a;
 645                         return;
 646                 }
 647
 648                 // Disallow moving items in elsewhere than player's inventory
 649                 // if not allowed to interact
 650                 if (!checkPriv(player->getName(), "interact") &&
 651                                 (!from_inv_is_current_player ||
 652                                 !to_inv_is_current_player)) {
 653                         infostream << "Cannot move outside of player's inventory: "
 654                                         << "No interact privilege" << std::endl;
 655                         delete a;
 656                         return;
 657                 }
 658         }
 659         /*
 660                 Handle restrictions and special cases of the drop action
 661         */
 662         else if (a->getType() == IAction::Drop) {
 663                 IDropAction *da = (IDropAction*)a;
 664
 665                 da->from_inv.applyCurrentPlayer(player->getName());
 666
 667                 setInventoryModified(da->from_inv, false);
 668
 669                 /*
 670                         Disable dropping items out of craftpreview
 671                 */
 672                 if (da->from_list == "craftpreview") {
 673                         infostream << "Ignoring IDropAction from "
 674                                         << (da->from_inv.dump()) << ":" << da->from_list
 675                                         << " because src is " << da->from_list << std::endl;
 676                         delete a;
 677                         return;
 678                 }
 679
 680                 // Disallow dropping items if not allowed to interact
 681                 if (!checkPriv(player->getName(), "interact")) {
 682                         delete a;
 683                         return;
 684                 }
 685
 686                 // Disallow dropping items if dead
 687                 if (playersao->isDead()) {
 688                         infostream << "Ignoring IDropAction from "
 689                                         << (da->from_inv.dump()) << ":" << da->from_list
 690                                         << " because player is dead." << std::endl;
 691                         delete a;
 692                         return;
 693                 }
 694         }
 695         /*
 696                 Handle restrictions and special cases of the craft action
 697         */
 698         else if (a->getType() == IAction::Craft) {
 699                 ICraftAction *ca = (ICraftAction*)a;
 700
 701                 ca->craft_inv.applyCurrentPlayer(player->getName());
 702
 703                 setInventoryModified(ca->craft_inv, false);
 704
 705                 //bool craft_inv_is_current_player =
 706                 //      (ca->craft_inv.type == InventoryLocation::PLAYER) &&
 707                 //      (ca->craft_inv.name == player->getName());
 708
 709                 // Disallow crafting if not allowed to interact
 710                 if (!checkPriv(player->getName(), "interact")) {
 711                         infostream << "Cannot craft: "
 712                                         << "No interact privilege" << std::endl;
 713                         delete a;
 714                         return;
 715                 }
 716         }
 717
 718         // Do the action
 719         a->apply(this, playersao, this);
 720         // Eat the action
 721         delete a;
 722
 723         SendInventory(playersao);
 724 }
 725
 726 void Server::handleCommand_ChatMessage(NetworkPacket* pkt)
 727 {
 728         /*
 729                 u16 command
 730                 u16 length
 731                 wstring message
 732         */
 733         u16 len;
 734         *pkt >> len;
 735
 736         std::wstring message;
 737         for (u16 i = 0; i < len; i++) {
 738                 u16 tmp_wchar;
 739                 *pkt >> tmp_wchar;
 740
 741                 message += (wchar_t)tmp_wchar;
 742         }
 743
 744         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
 745         if (player == NULL) {
 746                 errorstream << "Server::ProcessData(): Canceling: "
 747                                 "No player for peer_id=" << pkt->getPeerId()
 748                                 << " disconnecting peer!" << std::endl;
 749                 DisconnectPeer(pkt->getPeerId());
 750                 return;
 751         }
 752
 753         // Get player name of this client
 754         std::string name = player->getName();
 755         std::wstring wname = narrow_to_wide(name);
 756
 757         std::wstring answer_to_sender = handleChat(name, wname, message, true, player);
 758         if (!answer_to_sender.empty()) {
 759                 // Send the answer to sender
 760                 SendChatMessage(pkt->getPeerId(), ChatMessage(CHATMESSAGE_TYPE_NORMAL,
 761                                 answer_to_sender, wname));
 762         }
 763 }
 764
 765 void Server::handleCommand_Damage(NetworkPacket* pkt)
 766 {
 767         u8 damage;
 768
 769         *pkt >> damage;
 770
 771         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
 772
 773         if (player == NULL) {
 774                 errorstream << "Server::ProcessData(): Canceling: "
 775                                 "No player for peer_id=" << pkt->getPeerId()
 776                                 << " disconnecting peer!" << std::endl;
 777                 DisconnectPeer(pkt->getPeerId());
 778                 return;
 779         }
 780
 781         PlayerSAO *playersao = player->getPlayerSAO();
 782         if (playersao == NULL) {
 783                 errorstream << "Server::ProcessData(): Canceling: "
 784                                 "No player object for peer_id=" << pkt->getPeerId()
 785                                 << " disconnecting peer!" << std::endl;
 786                 DisconnectPeer(pkt->getPeerId());
 787                 return;
 788         }
 789
 790         if (g_settings->getBool("enable_damage")) {
 791                 if (playersao->isDead()) {
 792                         verbosestream << "Server::ProcessData(): Info: "
 793                                 "Ignoring damage as player " << player->getName()
 794                                 << " is already dead." << std::endl;
 795                         return;
 796                 }
 797
 798                 actionstream << player->getName() << " damaged by "
 799                                 << (int)damage << " hp at " << PP(playersao->getBasePosition() / BS)
 800                                 << std::endl;
 801
 802                 playersao->setHP(playersao->getHP() - damage);
 803                 SendPlayerHPOrDie(playersao);
 804         }
 805 }
 806
 807 void Server::handleCommand_Password(NetworkPacket* pkt)
 808 {
 809         if (pkt->getSize() != PASSWORD_SIZE * 2)
 810                 return;
 811
 812         std::string oldpwd;
 813         std::string newpwd;
 814
 815         // Deny for clients using the new protocol
 816         RemoteClient* client = getClient(pkt->getPeerId(), CS_Created);
 817         if (client->net_proto_version >= 25) {
 818                 infostream << "Server::handleCommand_Password(): Denying change: "
 819                         << " Client protocol version for peer_id=" << pkt->getPeerId()
 820                         << " too new!" << std::endl;
 821                 return;
 822         }
 823
 824         for (u16 i = 0; i < PASSWORD_SIZE - 1; i++) {
 825                 char c = pkt->getChar(i);
 826                 if (c == 0)
 827                         break;
 828                 oldpwd += c;
 829         }
 830
 831         for (u16 i = 0; i < PASSWORD_SIZE - 1; i++) {
 832                 char c = pkt->getChar(PASSWORD_SIZE + i);
 833                 if (c == 0)
 834                         break;
 835                 newpwd += c;
 836         }
 837
 838         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
 839         if (player == NULL) {
 840                 errorstream << "Server::ProcessData(): Canceling: "
 841                                 "No player for peer_id=" << pkt->getPeerId()
 842                                 << " disconnecting peer!" << std::endl;
 843                 DisconnectPeer(pkt->getPeerId());
 844                 return;
 845         }
 846
 847         if (!base64_is_valid(newpwd)) {
 848                 infostream<<"Server: " << player->getName() <<
 849                                 " supplied invalid password hash" << std::endl;
 850                 // Wrong old password supplied!!
 851                 SendChatMessage(pkt->getPeerId(), ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
 852                                 L"Invalid new password hash supplied. Password NOT changed."));
 853                 return;
 854         }
 855
 856         infostream << "Server: Client requests a password change from "
 857                         << "'" << oldpwd << "' to '" << newpwd << "'" << std::endl;
 858
 859         std::string playername = player->getName();
 860
 861         std::string checkpwd;
 862         m_script->getAuth(playername, &checkpwd, NULL);
 863
 864         if (oldpwd != checkpwd) {
 865                 infostream << "Server: invalid old password" << std::endl;
 866                 // Wrong old password supplied!!
 867                 SendChatMessage(pkt->getPeerId(), ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
 868                                 L"Invalid old password supplied. Password NOT changed."));
 869                 return;
 870         }
 871
 872         bool success = m_script->setPassword(playername, newpwd);
 873         if (success) {
 874                 actionstream << player->getName() << " changes password" << std::endl;
 875                 SendChatMessage(pkt->getPeerId(), ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
 876                                 L"Password change successful."));
 877         } else {
 878                 actionstream << player->getName() << " tries to change password but "
 879                                 << "it fails" << std::endl;
 880                 SendChatMessage(pkt->getPeerId(), ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
 881                                 L"Password change failed or unavailable."));
 882         }
 883 }
 884
 885 void Server::handleCommand_PlayerItem(NetworkPacket* pkt)
 886 {
 887         if (pkt->getSize() < 2)
 888                 return;
 889
 890         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
 891
 892         if (player == NULL) {
 893                 errorstream << "Server::ProcessData(): Canceling: "
 894                                 "No player for peer_id=" << pkt->getPeerId()
 895                                 << " disconnecting peer!" << std::endl;
 896                 DisconnectPeer(pkt->getPeerId());
 897                 return;
 898         }
 899
 900         PlayerSAO *playersao = player->getPlayerSAO();
 901         if (playersao == NULL) {
 902                 errorstream << "Server::ProcessData(): Canceling: "
 903                                 "No player object for peer_id=" << pkt->getPeerId()
 904                                 << " disconnecting peer!" << std::endl;
 905                 DisconnectPeer(pkt->getPeerId());
 906                 return;
 907         }
 908
 909         u16 item;
 910
 911         *pkt >> item;
 912
 913         playersao->setWieldIndex(item);
 914 }
 915
 916 void Server::handleCommand_Respawn(NetworkPacket* pkt)
 917 {
 918         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
 919         if (player == NULL) {
 920                 errorstream << "Server::ProcessData(): Canceling: "
 921                                 "No player for peer_id=" << pkt->getPeerId()
 922                                 << " disconnecting peer!" << std::endl;
 923                 DisconnectPeer(pkt->getPeerId());
 924                 return;
 925         }
 926
 927         PlayerSAO *playersao = player->getPlayerSAO();
 928         assert(playersao);
 929
 930         if (!playersao->isDead())
 931                 return;
 932
 933         RespawnPlayer(pkt->getPeerId());
 934
 935         actionstream << player->getName() << " respawns at "
 936                         << PP(playersao->getBasePosition() / BS) << std::endl;
 937
 938         // ActiveObject is added to environment in AsyncRunStep after
 939         // the previous addition has been successfully removed
 940 }
 941
 942 void Server::handleCommand_Interact(NetworkPacket* pkt)
 943 {
 944         /*
 945                 [0] u16 command
 946                 [2] u8 action
 947                 [3] u16 item
 948                 [5] u32 length of the next item (plen)
 949                 [9] serialized PointedThing
 950                 [9 + plen] player position information
 951                 actions:
 952                 0: start digging (from undersurface) or use
 953                 1: stop digging (all parameters ignored)
 954                 2: digging completed
 955                 3: place block or item (to abovesurface)
 956                 4: use item
 957                 5: rightclick air ("activate")
 958         */
 959         u8 action;
 960         u16 item_i;
 961         *pkt >> action;
 962         *pkt >> item_i;
 963         std::istringstream tmp_is(pkt->readLongString(), std::ios::binary);
 964         PointedThing pointed;
 965         pointed.deSerialize(tmp_is);
 966
 967         verbosestream << "TOSERVER_INTERACT: action=" << (int)action << ", item="
 968                         << item_i << ", pointed=" << pointed.dump() << std::endl;
 969
 970         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
 971
 972         if (player == NULL) {
 973                 errorstream << "Server::ProcessData(): Canceling: "
 974                                 "No player for peer_id=" << pkt->getPeerId()
 975                                 << " disconnecting peer!" << std::endl;
 976                 DisconnectPeer(pkt->getPeerId());
 977                 return;
 978         }
 979
 980         PlayerSAO *playersao = player->getPlayerSAO();
 981         if (playersao == NULL) {
 982                 errorstream << "Server::ProcessData(): Canceling: "
 983                                 "No player object for peer_id=" << pkt->getPeerId()
 984                                 << " disconnecting peer!" << std::endl;
 985                 DisconnectPeer(pkt->getPeerId());
 986                 return;
 987         }
 988
 989         if (playersao->isDead()) {
 990                 actionstream << "Server: NoCheat: " << player->getName()
 991                                 << " tried to interact while dead; ignoring." << std::endl;
 992                 if (pointed.type == POINTEDTHING_NODE) {
 993                         // Re-send block to revert change on client-side
 994                         RemoteClient *client = getClient(pkt->getPeerId());
 995                         v3s16 blockpos = getNodeBlockPos(pointed.node_undersurface);
 996                         client->SetBlockNotSent(blockpos);
 997                 }
 998                 // Call callbacks
 999                 m_script->on_cheat(playersao, "interacted_while_dead");
1000                 return;
1001         }
1002
1003         process_PlayerPos(player, playersao, pkt);
1004
1005         v3f player_pos = playersao->getLastGoodPosition();
1006
1007         // Update wielded item
1008         playersao->setWieldIndex(item_i);
1009
1010         // Get pointed to node (undefined if not POINTEDTYPE_NODE)
1011         v3s16 p_under = pointed.node_undersurface;
1012         v3s16 p_above = pointed.node_abovesurface;
1013
1014         // Get pointed to object (NULL if not POINTEDTYPE_OBJECT)
1015         ServerActiveObject *pointed_object = NULL;
1016         if (pointed.type == POINTEDTHING_OBJECT) {
1017                 pointed_object = m_env->getActiveObject(pointed.object_id);
1018                 if (pointed_object == NULL) {
1019                         verbosestream << "TOSERVER_INTERACT: "
1020                                 "pointed object is NULL" << std::endl;
1021                         return;
1022                 }
1023
1024         }
1025
1026         v3f pointed_pos_under = player_pos;
1027         v3f pointed_pos_above = player_pos;
1028         if (pointed.type == POINTEDTHING_NODE) {
1029                 pointed_pos_under = intToFloat(p_under, BS);
1030                 pointed_pos_above = intToFloat(p_above, BS);
1031         }
1032         else if (pointed.type == POINTEDTHING_OBJECT) {
1033                 pointed_pos_under = pointed_object->getBasePosition();
1034                 pointed_pos_above = pointed_pos_under;
1035         }
1036
1037         /*
1038                 Make sure the player is allowed to do it
1039         */
1040         if (!checkPriv(player->getName(), "interact")) {
1041                 actionstream<<player->getName()<<" attempted to interact with "
1042                                 <<pointed.dump()<<" without 'interact' privilege"
1043                                 <<std::endl;
1044                 // Re-send block to revert change on client-side
1045                 RemoteClient *client = getClient(pkt->getPeerId());
1046                 // Digging completed -> under
1047                 if (action == 2) {
1048                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1049                         client->SetBlockNotSent(blockpos);
1050                 }
1051                 // Placement -> above
1052                 if (action == 3) {
1053                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_above, BS));
1054                         client->SetBlockNotSent(blockpos);
1055                 }
1056                 return;
1057         }
1058
1059         /*
1060                 Check that target is reasonably close
1061                 (only when digging or placing things)
1062         */
1063         static thread_local const bool enable_anticheat =
1064                         !g_settings->getBool("disable_anticheat");
1065
1066         if ((action == 0 || action == 2 || action == 3 || action == 4) &&
1067                         (enable_anticheat && !isSingleplayer())) {
1068                 float d = player_pos.getDistanceFrom(pointed_pos_under);
1069                 const ItemDefinition &playeritem_def =
1070                         playersao->getWieldedItem().getDefinition(m_itemdef);
1071                 float max_d = BS * playeritem_def.range;
1072                 InventoryList *hlist = playersao->getInventory()->getList("hand");
1073                 const ItemDefinition &hand_def =
1074                         hlist ? (hlist->getItem(0).getDefinition(m_itemdef)) : (m_itemdef->get(""));
1075                 float max_d_hand = BS * hand_def.range;
1076                 if (max_d < 0 && max_d_hand >= 0)
1077                         max_d = max_d_hand;
1078                 else if (max_d < 0)
1079                         max_d = BS * 4.0f;
1080                 // cube diagonal: sqrt(3) = 1.73
1081                 if (d > max_d * 1.73) {
1082                         actionstream << "Player " << player->getName()
1083                                         << " tried to access " << pointed.dump()
1084                                         << " from too far: "
1085                                         << "d=" << d <<", max_d=" << max_d
1086                                         << ". ignoring." << std::endl;
1087                         // Re-send block to revert change on client-side
1088                         RemoteClient *client = getClient(pkt->getPeerId());
1089                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1090                         client->SetBlockNotSent(blockpos);
1091                         // Call callbacks
1092                         m_script->on_cheat(playersao, "interacted_too_far");
1093                         // Do nothing else
1094                         return;
1095                 }
1096         }
1097
1098         /*
1099                 If something goes wrong, this player is to blame
1100         */
1101         RollbackScopeActor rollback_scope(m_rollback,
1102                         std::string("player:")+player->getName());
1103
1104         /*
1105                 0: start digging or punch object
1106         */
1107         if (action == 0) {
1108                 if (pointed.type == POINTEDTHING_NODE) {
1109                         MapNode n(CONTENT_IGNORE);
1110                         bool pos_ok;
1111
1112                         n = m_env->getMap().getNodeNoEx(p_under, &pos_ok);
1113                         if (!pos_ok) {
1114                                 infostream << "Server: Not punching: Node not found."
1115                                                 << " Adding block to emerge queue."
1116                                                 << std::endl;
1117                                 m_emerge->enqueueBlockEmerge(pkt->getPeerId(),
1118                                         getNodeBlockPos(p_above), false);
1119                         }
1120
1121                         if (n.getContent() != CONTENT_IGNORE)
1122                                 m_script->node_on_punch(p_under, n, playersao, pointed);
1123
1124                         // Cheat prevention
1125                         playersao->noCheatDigStart(p_under);
1126                 }
1127                 else if (pointed.type == POINTEDTHING_OBJECT) {
1128                         // Skip if object can't be interacted with anymore
1129                         if (pointed_object->isGone())
1130                                 return;
1131
1132                         actionstream<<player->getName()<<" punches object "
1133                                         <<pointed.object_id<<": "
1134                                         <<pointed_object->getDescription()<<std::endl;
1135
1136                         ItemStack punchitem = playersao->getWieldedItemOrHand();
1137                         ToolCapabilities toolcap =
1138                                         punchitem.getToolCapabilities(m_itemdef);
1139                         v3f dir = (pointed_object->getBasePosition() -
1140                                         (playersao->getBasePosition() + playersao->getEyeOffset())
1141                                                 ).normalize();
1142                         float time_from_last_punch =
1143                                 playersao->resetTimeFromLastPunch();
1144
1145                         s16 src_original_hp = pointed_object->getHP();
1146                         s16 dst_origin_hp = playersao->getHP();
1147
1148                         pointed_object->punch(dir, &toolcap, playersao,
1149                                         time_from_last_punch);
1150
1151                         // If the object is a player and its HP changed
1152                         if (src_original_hp != pointed_object->getHP() &&
1153                                         pointed_object->getType() == ACTIVEOBJECT_TYPE_PLAYER) {
1154                                 SendPlayerHPOrDie((PlayerSAO *)pointed_object);
1155                         }
1156
1157                         // If the puncher is a player and its HP changed
1158                         if (dst_origin_hp != playersao->getHP())
1159                                 SendPlayerHPOrDie(playersao);
1160                 }
1161
1162         } // action == 0
1163
1164         /*
1165                 1: stop digging
1166         */
1167         else if (action == 1) {
1168         } // action == 1
1169
1170         /*
1171                 2: Digging completed
1172         */
1173         else if (action == 2) {
1174                 // Only digging of nodes
1175                 if (pointed.type == POINTEDTHING_NODE) {
1176                         bool pos_ok;
1177                         MapNode n = m_env->getMap().getNodeNoEx(p_under, &pos_ok);
1178                         if (!pos_ok) {
1179                                 infostream << "Server: Not finishing digging: Node not found."
1180                                                 << " Adding block to emerge queue."
1181                                                 << std::endl;
1182                                 m_emerge->enqueueBlockEmerge(pkt->getPeerId(),
1183                                         getNodeBlockPos(p_above), false);
1184                         }
1185
1186                         /* Cheat prevention */
1187                         bool is_valid_dig = true;
1188                         if (enable_anticheat && !isSingleplayer()) {
1189                                 v3s16 nocheat_p = playersao->getNoCheatDigPos();
1190                                 float nocheat_t = playersao->getNoCheatDigTime();
1191                                 playersao->noCheatDigEnd();
1192                                 // If player didn't start digging this, ignore dig
1193                                 if (nocheat_p != p_under) {
1194                                         infostream << "Server: NoCheat: " << player->getName()
1195                                                         << " started digging "
1196                                                         << PP(nocheat_p) << " and completed digging "
1197                                                         << PP(p_under) << "; not digging." << std::endl;
1198                                         is_valid_dig = false;
1199                                         // Call callbacks
1200                                         m_script->on_cheat(playersao, "finished_unknown_dig");
1201                                 }
1202                                 // Get player's wielded item
1203                                 ItemStack playeritem = playersao->getWieldedItemOrHand();
1204                                 ToolCapabilities playeritem_toolcap =
1205                                                 playeritem.getToolCapabilities(m_itemdef);
1206                                 // Get diggability and expected digging time
1207                                 DigParams params = getDigParams(m_nodedef->get(n).groups,
1208                                                 &playeritem_toolcap);
1209                                 // If can't dig, try hand
1210                                 if (!params.diggable) {
1211                                         InventoryList *hlist = playersao->getInventory()->getList("hand");
1212                                         const ItemDefinition &hand =
1213                                                 hlist ? hlist->getItem(0).getDefinition(m_itemdef) : m_itemdef->get("");
1214                                         const ToolCapabilities *tp = hand.tool_capabilities;
1215                                         if (tp)
1216                                                 params = getDigParams(m_nodedef->get(n).groups, tp);
1217                                 }
1218                                 // If can't dig, ignore dig
1219                                 if (!params.diggable) {
1220                                         infostream << "Server: NoCheat: " << player->getName()
1221                                                         << " completed digging " << PP(p_under)
1222                                                         << ", which is not diggable with tool. not digging."
1223                                                         << std::endl;
1224                                         is_valid_dig = false;
1225                                         // Call callbacks
1226                                         m_script->on_cheat(playersao, "dug_unbreakable");
1227                                 }
1228                                 // Check digging time
1229                                 // If already invalidated, we don't have to
1230                                 if (!is_valid_dig) {
1231                                         // Well not our problem then
1232                                 }
1233                                 // Clean and long dig
1234                                 else if (params.time > 2.0 && nocheat_t * 1.2 > params.time) {
1235                                         // All is good, but grab time from pool; don't care if
1236                                         // it's actually available
1237                                         playersao->getDigPool().grab(params.time);
1238                                 }
1239                                 // Short or laggy dig
1240                                 // Try getting the time from pool
1241                                 else if (playersao->getDigPool().grab(params.time)) {
1242                                         // All is good
1243                                 }
1244                                 // Dig not possible
1245                                 else {
1246                                         infostream << "Server: NoCheat: " << player->getName()
1247                                                         << " completed digging " << PP(p_under)
1248                                                         << "too fast; not digging." << std::endl;
1249                                         is_valid_dig = false;
1250                                         // Call callbacks
1251                                         m_script->on_cheat(playersao, "dug_too_fast");
1252                                 }
1253                         }
1254
1255                         /* Actually dig node */
1256
1257                         if (is_valid_dig && n.getContent() != CONTENT_IGNORE)
1258                                 m_script->node_on_dig(p_under, n, playersao);
1259
1260                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1261                         RemoteClient *client = getClient(pkt->getPeerId());
1262                         // Send unusual result (that is, node not being removed)
1263                         if (m_env->getMap().getNodeNoEx(p_under).getContent() != CONTENT_AIR) {
1264                                 // Re-send block to revert change on client-side
1265                                 client->SetBlockNotSent(blockpos);
1266                         }
1267                         else {
1268                                 client->ResendBlockIfOnWire(blockpos);
1269                         }
1270                 }
1271         } // action == 2
1272
1273         /*
1274                 3: place block or right-click object
1275         */
1276         else if (action == 3) {
1277                 ItemStack item = playersao->getWieldedItem();
1278
1279                 // Reset build time counter
1280                 if (pointed.type == POINTEDTHING_NODE &&
1281                                 item.getDefinition(m_itemdef).type == ITEM_NODE)
1282                         getClient(pkt->getPeerId())->m_time_from_building = 0.0;
1283
1284                 if (pointed.type == POINTEDTHING_OBJECT) {
1285                         // Right click object
1286
1287                         // Skip if object can't be interacted with anymore
1288                         if (pointed_object->isGone())
1289                                 return;
1290
1291                         actionstream << player->getName() << " right-clicks object "
1292                                         << pointed.object_id << ": "
1293                                         << pointed_object->getDescription() << std::endl;
1294
1295                         // Do stuff
1296                         pointed_object->rightClick(playersao);
1297                 }
1298                 else if (m_script->item_OnPlace(
1299                                 item, playersao, pointed)) {
1300                         // Placement was handled in lua
1301
1302                         // Apply returned ItemStack
1303                         if (playersao->setWieldedItem(item)) {
1304                                 SendInventory(playersao);
1305                         }
1306                 }
1307
1308                 // If item has node placement prediction, always send the
1309                 // blocks to make sure the client knows what exactly happened
1310                 RemoteClient *client = getClient(pkt->getPeerId());
1311                 v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_above, BS));
1312                 v3s16 blockpos2 = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1313                 if (!item.getDefinition(m_itemdef).node_placement_prediction.empty()) {
1314                         client->SetBlockNotSent(blockpos);
1315                         if (blockpos2 != blockpos) {
1316                                 client->SetBlockNotSent(blockpos2);
1317                         }
1318                 }
1319                 else {
1320                         client->ResendBlockIfOnWire(blockpos);
1321                         if (blockpos2 != blockpos) {
1322                                 client->ResendBlockIfOnWire(blockpos2);
1323                         }
1324                 }
1325         } // action == 3
1326
1327         /*
1328                 4: use
1329         */
1330         else if (action == 4) {
1331                 ItemStack item = playersao->getWieldedItem();
1332
1333                 actionstream << player->getName() << " uses " << item.name
1334                                 << ", pointing at " << pointed.dump() << std::endl;
1335
1336                 if (m_script->item_OnUse(
1337                                 item, playersao, pointed)) {
1338                         // Apply returned ItemStack
1339                         if (playersao->setWieldedItem(item)) {
1340                                 SendInventory(playersao);
1341                         }
1342                 }
1343
1344         } // action == 4
1345
1346         /*
1347                 5: rightclick air
1348         */
1349         else if (action == 5) {
1350                 ItemStack item = playersao->getWieldedItem();
1351
1352                 actionstream << player->getName() << " activates "
1353                                 << item.name << std::endl;
1354
1355                 if (m_script->item_OnSecondaryUse(
1356                                 item, playersao)) {
1357                         if( playersao->setWieldedItem(item)) {
1358                                 SendInventory(playersao);
1359                         }
1360                 }
1361         }
1362
1363
1364         /*
1365                 Catch invalid actions
1366         */
1367         else {
1368                 warningstream << "Server: Invalid action "
1369                                 << action << std::endl;
1370         }
1371 }
1372
1373 void Server::handleCommand_RemovedSounds(NetworkPacket* pkt)
1374 {
1375         u16 num;
1376         *pkt >> num;
1377         for (u16 k = 0; k < num; k++) {
1378                 s32 id;
1379
1380                 *pkt >> id;
1381
1382                 std::unordered_map<s32, ServerPlayingSound>::iterator i =
1383                         m_playing_sounds.find(id);
1384                 if (i == m_playing_sounds.end())
1385                         continue;
1386
1387                 ServerPlayingSound &psound = i->second;
1388                 psound.clients.erase(pkt->getPeerId());
1389                 if (psound.clients.empty())
1390                         m_playing_sounds.erase(i++);
1391         }
1392 }
1393
1394 void Server::handleCommand_NodeMetaFields(NetworkPacket* pkt)
1395 {
1396         v3s16 p;
1397         std::string formname;
1398         u16 num;
1399
1400         *pkt >> p >> formname >> num;
1401
1402         StringMap fields;
1403         for (u16 k = 0; k < num; k++) {
1404                 std::string fieldname;
1405                 *pkt >> fieldname;
1406                 fields[fieldname] = pkt->readLongString();
1407         }
1408
1409         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
1410
1411         if (player == NULL) {
1412                 errorstream << "Server::ProcessData(): Canceling: "
1413                                 "No player for peer_id=" << pkt->getPeerId()
1414                                 << " disconnecting peer!" << std::endl;
1415                 DisconnectPeer(pkt->getPeerId());
1416                 return;
1417         }
1418
1419         PlayerSAO *playersao = player->getPlayerSAO();
1420         if (playersao == NULL) {
1421                 errorstream << "Server::ProcessData(): Canceling: "
1422                                 "No player object for peer_id=" << pkt->getPeerId()
1423                                 << " disconnecting peer!"  << std::endl;
1424                 DisconnectPeer(pkt->getPeerId());
1425                 return;
1426         }
1427
1428         // If something goes wrong, this player is to blame
1429         RollbackScopeActor rollback_scope(m_rollback,
1430                         std::string("player:")+player->getName());
1431
1432         // Check the target node for rollback data; leave others unnoticed
1433         RollbackNode rn_old(&m_env->getMap(), p, this);
1434
1435         m_script->node_on_receive_fields(p, formname, fields, playersao);
1436
1437         // Report rollback data
1438         RollbackNode rn_new(&m_env->getMap(), p, this);
1439         if (rollback() && rn_new != rn_old) {
1440                 RollbackAction action;
1441                 action.setSetNode(p, rn_old, rn_new);
1442                 rollback()->reportAction(action);
1443         }
1444 }
1445
1446 void Server::handleCommand_InventoryFields(NetworkPacket* pkt)
1447 {
1448         std::string formname;
1449         u16 num;
1450
1451         *pkt >> formname >> num;
1452
1453         StringMap fields;
1454         for (u16 k = 0; k < num; k++) {
1455                 std::string fieldname;
1456                 *pkt >> fieldname;
1457                 fields[fieldname] = pkt->readLongString();
1458         }
1459
1460         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
1461
1462         if (player == NULL) {
1463                 errorstream << "Server::ProcessData(): Canceling: "
1464                                 "No player for peer_id=" << pkt->getPeerId()
1465                                 << " disconnecting peer!" << std::endl;
1466                 DisconnectPeer(pkt->getPeerId());
1467                 return;
1468         }
1469
1470         PlayerSAO *playersao = player->getPlayerSAO();
1471         if (playersao == NULL) {
1472                 errorstream << "Server::ProcessData(): Canceling: "
1473                                 "No player object for peer_id=" << pkt->getPeerId()
1474                                 << " disconnecting peer!" << std::endl;
1475                 DisconnectPeer(pkt->getPeerId());
1476                 return;
1477         }
1478
1479         m_script->on_playerReceiveFields(playersao, formname, fields);
1480 }
1481
1482 void Server::handleCommand_FirstSrp(NetworkPacket* pkt)
1483 {
1484         RemoteClient* client = getClient(pkt->getPeerId(), CS_Invalid);
1485         ClientState cstate = client->getState();
1486
1487         std::string playername = client->getName();
1488
1489         std::string salt;
1490         std::string verification_key;
1491
1492         std::string addr_s = getPeerAddress(pkt->getPeerId()).serializeString();
1493         u8 is_empty;
1494
1495         *pkt >> salt >> verification_key >> is_empty;
1496
1497         verbosestream << "Server: Got TOSERVER_FIRST_SRP from " << addr_s
1498                 << ", with is_empty=" << (is_empty == 1) << std::endl;
1499
1500         // Either this packet is sent because the user is new or to change the password
1501         if (cstate == CS_HelloSent) {
1502                 if (!client->isMechAllowed(AUTH_MECHANISM_FIRST_SRP)) {
1503                         actionstream << "Server: Client from " << addr_s
1504                                         << " tried to set password without being "
1505                                         << "authenticated, or the username being new." << std::endl;
1506                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1507                         return;
1508                 }
1509
1510                 if (!isSingleplayer() &&
1511                                 g_settings->getBool("disallow_empty_password") &&
1512                                 is_empty == 1) {
1513                         actionstream << "Server: " << playername
1514                                         << " supplied empty password from " << addr_s << std::endl;
1515                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_EMPTY_PASSWORD);
1516                         return;
1517                 }
1518
1519                 std::string initial_ver_key;
1520
1521                 initial_ver_key = encode_srp_verifier(verification_key, salt);
1522                 m_script->createAuth(playername, initial_ver_key);
1523
1524                 acceptAuth(pkt->getPeerId(), false);
1525         } else {
1526                 if (cstate < CS_SudoMode) {
1527                         infostream << "Server::ProcessData(): Ignoring TOSERVER_FIRST_SRP from "
1528                                         << addr_s << ": " << "Client has wrong state " << cstate << "."
1529                                         << std::endl;
1530                         return;
1531                 }
1532                 m_clients.event(pkt->getPeerId(), CSE_SudoLeave);
1533                 std::string pw_db_field = encode_srp_verifier(verification_key, salt);
1534                 bool success = m_script->setPassword(playername, pw_db_field);
1535                 if (success) {
1536                         actionstream << playername << " changes password" << std::endl;
1537                         SendChatMessage(pkt->getPeerId(), ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
1538                                         L"Password change successful."));
1539                 } else {
1540                         actionstream << playername << " tries to change password but "
1541                                 << "it fails" << std::endl;
1542                         SendChatMessage(pkt->getPeerId(), ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
1543                                         L"Password change failed or unavailable."));
1544                 }
1545         }
1546 }
1547
1548 void Server::handleCommand_SrpBytesA(NetworkPacket* pkt)
1549 {
1550         RemoteClient* client = getClient(pkt->getPeerId(), CS_Invalid);
1551         ClientState cstate = client->getState();
1552
1553         bool wantSudo = (cstate == CS_Active);
1554
1555         if (!((cstate == CS_HelloSent) || (cstate == CS_Active))) {
1556                 actionstream << "Server: got SRP _A packet in wrong state "
1557                         << cstate << " from "
1558                         << getPeerAddress(pkt->getPeerId()).serializeString()
1559                         << ". Ignoring." << std::endl;
1560                 return;
1561         }
1562
1563         if (client->chosen_mech != AUTH_MECHANISM_NONE) {
1564                 actionstream << "Server: got SRP _A packet, while auth"
1565                         << "is already going on with mech " << client->chosen_mech
1566                         << " from " << getPeerAddress(pkt->getPeerId()).serializeString()
1567                         << " (wantSudo=" << wantSudo << "). Ignoring." << std::endl;
1568                 if (wantSudo) {
1569                         DenySudoAccess(pkt->getPeerId());
1570                         return;
1571                 }
1572
1573                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1574                 return;
1575         }
1576
1577         std::string bytes_A;
1578         u8 based_on;
1579         *pkt >> bytes_A >> based_on;
1580
1581         infostream << "Server: TOSERVER_SRP_BYTES_A received with "
1582                 << "based_on=" << int(based_on) << " and len_A="
1583                 << bytes_A.length() << "." << std::endl;
1584
1585         AuthMechanism chosen = (based_on == 0) ?
1586                 AUTH_MECHANISM_LEGACY_PASSWORD : AUTH_MECHANISM_SRP;
1587
1588         if (wantSudo) {
1589                 if (!client->isSudoMechAllowed(chosen)) {
1590                         actionstream << "Server: Player \"" << client->getName()
1591                                 << "\" at " << getPeerAddress(pkt->getPeerId()).serializeString()
1592                                 << " tried to change password using unallowed mech "
1593                                 << chosen << "." << std::endl;
1594                         DenySudoAccess(pkt->getPeerId());
1595                         return;
1596                 }
1597         } else {
1598                 if (!client->isMechAllowed(chosen)) {
1599                         actionstream << "Server: Client tried to authenticate from "
1600                                 << getPeerAddress(pkt->getPeerId()).serializeString()
1601                                 << " using unallowed mech " << chosen << "." << std::endl;
1602                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1603                         return;
1604                 }
1605         }
1606
1607         client->chosen_mech = chosen;
1608
1609         std::string salt;
1610         std::string verifier;
1611
1612         if (based_on == 0) {
1613
1614                 generate_srp_verifier_and_salt(client->getName(), client->enc_pwd,
1615                         &verifier, &salt);
1616         } else if (!decode_srp_verifier_and_salt(client->enc_pwd, &verifier, &salt)) {
1617                 // Non-base64 errors should have been catched in the init handler
1618                 actionstream << "Server: User " << client->getName()
1619                         << " tried to log in, but srp verifier field"
1620                         << " was invalid (most likely invalid base64)." << std::endl;
1621                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_SERVER_FAIL);
1622                 return;
1623         }
1624
1625         char *bytes_B = 0;
1626         size_t len_B = 0;
1627
1628         client->auth_data = srp_verifier_new(SRP_SHA256, SRP_NG_2048,
1629                 client->getName().c_str(),
1630                 (const unsigned char *) salt.c_str(), salt.size(),
1631                 (const unsigned char *) verifier.c_str(), verifier.size(),
1632                 (const unsigned char *) bytes_A.c_str(), bytes_A.size(),
1633                 NULL, 0,
1634                 (unsigned char **) &bytes_B, &len_B, NULL, NULL);
1635
1636         if (!bytes_B) {
1637                 actionstream << "Server: User " << client->getName()
1638                         << " tried to log in, SRP-6a safety check violated in _A handler."
1639                         << std::endl;
1640                 if (wantSudo) {
1641                         DenySudoAccess(pkt->getPeerId());
1642                         return;
1643                 }
1644
1645                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1646                 return;
1647         }
1648
1649         NetworkPacket resp_pkt(TOCLIENT_SRP_BYTES_S_B, 0, pkt->getPeerId());
1650         resp_pkt << salt << std::string(bytes_B, len_B);
1651         Send(&resp_pkt);
1652 }
1653
1654 void Server::handleCommand_SrpBytesM(NetworkPacket* pkt)
1655 {
1656         RemoteClient* client = getClient(pkt->getPeerId(), CS_Invalid);
1657         ClientState cstate = client->getState();
1658
1659         bool wantSudo = (cstate == CS_Active);
1660
1661         verbosestream << "Server: Received TOCLIENT_SRP_BYTES_M." << std::endl;
1662
1663         if (!((cstate == CS_HelloSent) || (cstate == CS_Active))) {
1664                 actionstream << "Server: got SRP _M packet in wrong state "
1665                         << cstate << " from "
1666                         << getPeerAddress(pkt->getPeerId()).serializeString()
1667                         << ". Ignoring." << std::endl;
1668                 return;
1669         }
1670
1671         if (client->chosen_mech != AUTH_MECHANISM_SRP &&
1672                         client->chosen_mech != AUTH_MECHANISM_LEGACY_PASSWORD) {
1673                 actionstream << "Server: got SRP _M packet, while auth"
1674                         << "is going on with mech " << client->chosen_mech
1675                         << " from " << getPeerAddress(pkt->getPeerId()).serializeString()
1676                         << " (wantSudo=" << wantSudo << "). Denying." << std::endl;
1677                 if (wantSudo) {
1678                         DenySudoAccess(pkt->getPeerId());
1679                         return;
1680                 }
1681
1682                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1683                 return;
1684         }
1685
1686         std::string bytes_M;
1687         *pkt >> bytes_M;
1688
1689         if (srp_verifier_get_session_key_length((SRPVerifier *) client->auth_data)
1690                         != bytes_M.size()) {
1691                 actionstream << "Server: User " << client->getName()
1692                         << " at " << getPeerAddress(pkt->getPeerId()).serializeString()
1693                         << " sent bytes_M with invalid length " << bytes_M.size() << std::endl;
1694                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1695                 return;
1696         }
1697
1698         unsigned char *bytes_HAMK = 0;
1699
1700         srp_verifier_verify_session((SRPVerifier *) client->auth_data,
1701                 (unsigned char *)bytes_M.c_str(), &bytes_HAMK);
1702
1703         if (!bytes_HAMK) {
1704                 if (wantSudo) {
1705                         actionstream << "Server: User " << client->getName()
1706                                 << " at " << getPeerAddress(pkt->getPeerId()).serializeString()
1707                                 << " tried to change their password, but supplied wrong"
1708                                 << " (SRP) password for authentication." << std::endl;
1709                         DenySudoAccess(pkt->getPeerId());
1710                         return;
1711                 }
1712
1713                 actionstream << "Server: User " << client->getName()
1714                         << " at " << getPeerAddress(pkt->getPeerId()).serializeString()
1715                         << " supplied wrong password (auth mechanism: SRP)."
1716                         << std::endl;
1717                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_PASSWORD);
1718                 return;
1719         }
1720
1721         if (client->create_player_on_auth_success) {
1722                 std::string playername = client->getName();
1723                 m_script->createAuth(playername, client->enc_pwd);
1724
1725                 std::string checkpwd; // not used, but needed for passing something
1726                 if (!m_script->getAuth(playername, &checkpwd, NULL)) {
1727                         actionstream << "Server: " << playername << " cannot be authenticated"
1728                                 << " (auth handler does not work?)" << std::endl;
1729                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_SERVER_FAIL);
1730                         return;
1731                 }
1732                 client->create_player_on_auth_success = false;
1733         }
1734
1735         acceptAuth(pkt->getPeerId(), wantSudo);
1736 }
1737
1738 /*
1739  * Mod channels
1740  */
1741
1742 void Server::handleCommand_ModChannelJoin(NetworkPacket *pkt)
1743 {
1744         std::string channel_name;
1745         *pkt >> channel_name;
1746
1747         NetworkPacket resp_pkt(TOCLIENT_MODCHANNEL_SIGNAL, 1 + 2 + channel_name.size(),
1748                 pkt->getPeerId());
1749
1750         // Send signal to client to notify join succeed or not
1751         if (g_settings->getBool("enable_mod_channels") &&
1752                         m_modchannel_mgr->joinChannel(channel_name, pkt->getPeerId())) {
1753                 resp_pkt << (u8) MODCHANNEL_SIGNAL_JOIN_OK;
1754                 infostream << "Peer " << pkt->getPeerId() << " joined channel " << channel_name
1755                                 << std::endl;
1756         }
1757         else {
1758                 resp_pkt << (u8)MODCHANNEL_SIGNAL_JOIN_FAILURE;
1759                 infostream << "Peer " << pkt->getPeerId() << " tried to join channel "
1760                         << channel_name << ", but was already registered." << std::endl;
1761         }
1762         resp_pkt << channel_name;
1763         Send(&resp_pkt);
1764 }
1765
1766 void Server::handleCommand_ModChannelLeave(NetworkPacket *pkt)
1767 {
1768         std::string channel_name;
1769         *pkt >> channel_name;
1770
1771         NetworkPacket resp_pkt(TOCLIENT_MODCHANNEL_SIGNAL, 1 + 2 + channel_name.size(),
1772                 pkt->getPeerId());
1773
1774         // Send signal to client to notify join succeed or not
1775         if (g_settings->getBool("enable_mod_channels") &&
1776                         m_modchannel_mgr->leaveChannel(channel_name, pkt->getPeerId())) {
1777                 resp_pkt << (u8)MODCHANNEL_SIGNAL_LEAVE_OK;
1778                 infostream << "Peer " << pkt->getPeerId() << " left channel " << channel_name
1779                                 << std::endl;
1780         } else {
1781                 resp_pkt << (u8) MODCHANNEL_SIGNAL_LEAVE_FAILURE;
1782                 infostream << "Peer " << pkt->getPeerId() << " left channel " << channel_name
1783                                 << ", but was not registered." << std::endl;
1784         }
1785         resp_pkt << channel_name;
1786         Send(&resp_pkt);
1787 }
1788
1789 void Server::handleCommand_ModChannelMsg(NetworkPacket *pkt)
1790 {
1791         std::string channel_name, channel_msg;
1792         *pkt >> channel_name >> channel_msg;
1793
1794         verbosestream << "Mod channel message received from peer " << pkt->getPeerId()
1795                         << " on channel " << channel_name << " message: " << channel_msg << std::endl;
1796
1797         // If mod channels are not enabled, discard message
1798         if (!g_settings->getBool("enable_mod_channels")) {
1799                 return;
1800         }
1801
1802         // If channel not registered, signal it and ignore message
1803         if (!m_modchannel_mgr->channelRegistered(channel_name)) {
1804                 NetworkPacket resp_pkt(TOCLIENT_MODCHANNEL_SIGNAL, 1 + 2 + channel_name.size(),
1805                         pkt->getPeerId());
1806                 resp_pkt << (u8)MODCHANNEL_SIGNAL_CHANNEL_NOT_REGISTERED << channel_name;
1807                 Send(&resp_pkt);
1808                 return;
1809         }
1810
1811         // @TODO: filter, rate limit
1812
1813         broadcastModChannelMessage(channel_name, channel_msg, pkt->getPeerId());
1814 }