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 "server.h"
  21 #include "log.h"
  22
  23 #include "content_abm.h"
  24 #include "content_sao.h"
  25 #include "emerge.h"
  26 #include "nodedef.h"
  27 #include "player.h"
  28 #include "rollback_interface.h"
  29 #include "scripting_game.h"
  30 #include "settings.h"
  31 #include "tool.h"
  32 #include "version.h"
  33 #include "network/networkprotocol.h"
  34 #include "network/serveropcodes.h"
  35 #include "util/auth.h"
  36 #include "util/base64.h"
  37 #include "util/pointedthing.h"
  38 #include "util/serialize.h"
  39 #include "util/srp.h"
  40
  41 void Server::handleCommand_Deprecated(NetworkPacket* pkt)
  42 {
  43         infostream << "Server: " << toServerCommandTable[pkt->getCommand()].name
  44                 << " not supported anymore" << std::endl;
  45 }
  46
  47 void Server::handleCommand_Init(NetworkPacket* pkt)
  48 {
  49
  50         if(pkt->getSize() < 1)
  51                 return;
  52
  53         RemoteClient* client = getClient(pkt->getPeerId(), CS_Created);
  54
  55         std::string addr_s;
  56         try {
  57                 Address address = getPeerAddress(pkt->getPeerId());
  58                 addr_s = address.serializeString();
  59         }
  60         catch (con::PeerNotFoundException &e) {
  61                 /*
  62                  * no peer for this packet found
  63                  * most common reason is peer timeout, e.g. peer didn't
  64                  * respond for some time, your server was overloaded or
  65                  * things like that.
  66                  */
  67                 infostream << "Server::ProcessData(): Canceling: peer "
  68                                 << pkt->getPeerId() << " not found" << std::endl;
  69                 return;
  70         }
  71
  72         // If net_proto_version is set, this client has already been handled
  73         if (client->getState() > CS_Created) {
  74                 verbosestream << "Server: Ignoring multiple TOSERVER_INITs from "
  75                                 << addr_s << " (peer_id=" << pkt->getPeerId() << ")" << std::endl;
  76                 return;
  77         }
  78
  79         verbosestream << "Server: Got TOSERVER_INIT from " << addr_s << " (peer_id="
  80                         << pkt->getPeerId() << ")" << std::endl;
  81
  82         // Do not allow multiple players in simple singleplayer mode.
  83         // This isn't a perfect way to do it, but will suffice for now
  84         if (m_simple_singleplayer_mode && m_clients.getClientIDs().size() > 1) {
  85                 infostream << "Server: Not allowing another client (" << addr_s
  86                                 << ") to connect in simple singleplayer mode" << std::endl;
  87                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_SINGLEPLAYER);
  88                 return;
  89         }
  90
  91         // First byte after command is maximum supported
  92         // serialization version
  93         u8 client_max;
  94         u16 supp_compr_modes;
  95         u16 min_net_proto_version = 0;
  96         u16 max_net_proto_version;
  97         std::string playerName;
  98
  99         *pkt >> client_max >> supp_compr_modes >> min_net_proto_version
 100                         >> max_net_proto_version >> playerName;
 101
 102         u8 our_max = SER_FMT_VER_HIGHEST_READ;
 103         // Use the highest version supported by both
 104         u8 depl_serial_v = std::min(client_max, our_max);
 105         // If it's lower than the lowest supported, give up.
 106         if (depl_serial_v < SER_FMT_VER_LOWEST)
 107                 depl_serial_v = SER_FMT_VER_INVALID;
 108
 109         if (depl_serial_v == SER_FMT_VER_INVALID) {
 110                 actionstream << "Server: A mismatched client tried to connect from "
 111                                 << addr_s << std::endl;
 112                 infostream<<"Server: Cannot negotiate serialization version with "
 113                                 << addr_s << std::endl;
 114                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_VERSION);
 115                 return;
 116         }
 117
 118         client->setPendingSerializationVersion(depl_serial_v);
 119
 120         /*
 121                 Read and check network protocol version
 122         */
 123
 124         u16 net_proto_version = 0;
 125
 126         // Figure out a working version if it is possible at all
 127         if (max_net_proto_version >= SERVER_PROTOCOL_VERSION_MIN ||
 128                         min_net_proto_version <= SERVER_PROTOCOL_VERSION_MAX) {
 129                 // If maximum is larger than our maximum, go with our maximum
 130                 if (max_net_proto_version > SERVER_PROTOCOL_VERSION_MAX)
 131                         net_proto_version = SERVER_PROTOCOL_VERSION_MAX;
 132                 // Else go with client's maximum
 133                 else
 134                         net_proto_version = max_net_proto_version;
 135         }
 136
 137         verbosestream << "Server: " << addr_s << ": Protocol version: min: "
 138                         << min_net_proto_version << ", max: " << max_net_proto_version
 139                         << ", chosen: " << net_proto_version << std::endl;
 140
 141         client->net_proto_version = net_proto_version;
 142
 143         // On this handler at least protocol version 25 is required
 144         if (net_proto_version < 25 ||
 145                         net_proto_version < SERVER_PROTOCOL_VERSION_MIN ||
 146                         net_proto_version > SERVER_PROTOCOL_VERSION_MAX) {
 147                 actionstream << "Server: A mismatched client tried to connect from "
 148                                 << addr_s << std::endl;
 149                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_VERSION);
 150                 return;
 151         }
 152
 153         if (g_settings->getBool("strict_protocol_version_checking")) {
 154                 if (net_proto_version != LATEST_PROTOCOL_VERSION) {
 155                         actionstream << "Server: A mismatched (strict) client tried to "
 156                                         << "connect from " << addr_s << std::endl;
 157                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_VERSION);
 158                         return;
 159                 }
 160         }
 161
 162         /*
 163                 Validate player name
 164         */
 165         const char* playername = playerName.c_str();
 166
 167         size_t pns = playerName.size();
 168         if (pns == 0 || pns > PLAYERNAME_SIZE) {
 169                 actionstream << "Server: Player with "
 170                         << ((pns > PLAYERNAME_SIZE) ? "a too long" : "an empty")
 171                         << " name tried to connect from " << addr_s << std::endl;
 172                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_NAME);
 173                 return;
 174         }
 175
 176         if (string_allowed(playerName, PLAYERNAME_ALLOWED_CHARS) == false) {
 177                 actionstream << "Server: Player with an invalid name "
 178                                 << "tried to connect from " << addr_s << std::endl;
 179                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_CHARS_IN_NAME);
 180                 return;
 181         }
 182
 183         m_clients.setPlayerName(pkt->getPeerId(), playername);
 184         //TODO (later) case insensitivity
 185
 186         std::string legacyPlayerNameCasing = playerName;
 187
 188         if (!isSingleplayer() && strcasecmp(playername, "singleplayer") == 0) {
 189                 actionstream << "Server: Player with the name \"singleplayer\" "
 190                                 << "tried to connect from " << addr_s << std::endl;
 191                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_NAME);
 192                 return;
 193         }
 194
 195         {
 196                 std::string reason;
 197                 if (m_script->on_prejoinplayer(playername, addr_s, &reason)) {
 198                         actionstream << "Server: Player with the name \"" << playerName << "\" "
 199                                         << "tried to connect from " << addr_s << " "
 200                                         << "but it was disallowed for the following reason: "
 201                                         << reason << std::endl;
 202                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_CUSTOM_STRING,
 203                                         reason.c_str());
 204                         return;
 205                 }
 206         }
 207
 208         infostream << "Server: New connection: \"" << playerName << "\" from "
 209                         << addr_s << " (peer_id=" << pkt->getPeerId() << ")" << std::endl;
 210
 211         // Enforce user limit.
 212         // Don't enforce for users that have some admin right
 213         if (m_clients.getClientIDs(CS_Created).size() >= g_settings->getU16("max_users") &&
 214                         !checkPriv(playername, "server") &&
 215                         !checkPriv(playername, "ban") &&
 216                         !checkPriv(playername, "privs") &&
 217                         !checkPriv(playername, "password") &&
 218                         playername != g_settings->get("name")) {
 219                 actionstream << "Server: " << playername << " tried to join from "
 220                                 << addr_s << ", but there" << " are already max_users="
 221                                 << g_settings->getU16("max_users") << " players." << std::endl;
 222                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_TOO_MANY_USERS);
 223                 return;
 224         }
 225
 226         /*
 227                 Compose auth methods for answer
 228         */
 229         std::string encpwd; // encrypted Password field for the user
 230         bool has_auth = m_script->getAuth(playername, &encpwd, NULL);
 231         u32 auth_mechs = 0;
 232
 233         client->chosen_mech = AUTH_MECHANISM_NONE;
 234
 235         if (has_auth) {
 236                 std::vector<std::string> pwd_components = str_split(encpwd, '#');
 237                 if (pwd_components.size() == 4) {
 238                         if (pwd_components[1] == "1") { // 1 means srp
 239                                 auth_mechs |= AUTH_MECHANISM_SRP;
 240                                 client->enc_pwd = encpwd;
 241                         } else {
 242                                 actionstream << "User " << playername
 243                                         << " tried to log in, but password field"
 244                                         << " was invalid (unknown mechcode)." << std::endl;
 245                                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_SERVER_FAIL);
 246                                 return;
 247                         }
 248                 } else if (base64_is_valid(encpwd)) {
 249                         auth_mechs |= AUTH_MECHANISM_LEGACY_PASSWORD;
 250                         client->enc_pwd = encpwd;
 251                 } else {
 252                         actionstream << "User " << playername
 253                                 << " tried to log in, but password field"
 254                                 << " was invalid (invalid base64)." << std::endl;
 255                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_SERVER_FAIL);
 256                         return;
 257                 }
 258         } else {
 259                 std::string default_password = g_settings->get("default_password");
 260                 if (default_password.length() == 0) {
 261                         auth_mechs |= AUTH_MECHANISM_FIRST_SRP;
 262                 } else {
 263                         // Take care of default passwords.
 264                         client->enc_pwd = getSRPVerifier(playerName, default_password);
 265                         auth_mechs |= AUTH_MECHANISM_SRP;
 266                 }
 267         }
 268
 269         /*
 270                 Answer with a TOCLIENT_HELLO
 271         */
 272
 273         verbosestream << "Sending TOCLIENT_HELLO with auth method field: "
 274                 << auth_mechs << std::endl;
 275
 276         NetworkPacket resp_pkt(TOCLIENT_HELLO, 1 + 4
 277                 + legacyPlayerNameCasing.size(), pkt->getPeerId());
 278
 279         u16 depl_compress_mode = NETPROTO_COMPRESSION_NONE;
 280         resp_pkt << depl_serial_v << depl_compress_mode << net_proto_version
 281                 << auth_mechs << legacyPlayerNameCasing;
 282
 283         Send(&resp_pkt);
 284
 285         client->allowed_auth_mechs = auth_mechs;
 286         client->setDeployedCompressionMode(depl_compress_mode);
 287
 288         m_clients.event(pkt->getPeerId(), CSE_Hello);
 289 }
 290
 291 void Server::handleCommand_Init_Legacy(NetworkPacket* pkt)
 292 {
 293         // [0] u8 SER_FMT_VER_HIGHEST_READ
 294         // [1] u8[20] player_name
 295         // [21] u8[28] password <--- can be sent without this, from old versions
 296
 297         if (pkt->getSize() < 1+PLAYERNAME_SIZE)
 298                 return;
 299
 300         RemoteClient* client = getClient(pkt->getPeerId(), CS_Created);
 301
 302         std::string addr_s;
 303         try {
 304                 Address address = getPeerAddress(pkt->getPeerId());
 305                 addr_s = address.serializeString();
 306         }
 307         catch (con::PeerNotFoundException &e) {
 308                 /*
 309                  * no peer for this packet found
 310                  * most common reason is peer timeout, e.g. peer didn't
 311                  * respond for some time, your server was overloaded or
 312                  * things like that.
 313                  */
 314                 infostream << "Server::ProcessData(): Canceling: peer "
 315                                 << pkt->getPeerId() << " not found" << std::endl;
 316                 return;
 317         }
 318
 319         // If net_proto_version is set, this client has already been handled
 320         if (client->getState() > CS_Created) {
 321                 verbosestream << "Server: Ignoring multiple TOSERVER_INITs from "
 322                                 << addr_s << " (peer_id=" << pkt->getPeerId() << ")" << std::endl;
 323                 return;
 324         }
 325
 326         verbosestream << "Server: Got TOSERVER_INIT_LEGACY from " << addr_s << " (peer_id="
 327                         << pkt->getPeerId() << ")" << std::endl;
 328
 329         // Do not allow multiple players in simple singleplayer mode.
 330         // This isn't a perfect way to do it, but will suffice for now
 331         if (m_simple_singleplayer_mode && m_clients.getClientIDs().size() > 1) {
 332                 infostream << "Server: Not allowing another client (" << addr_s
 333                                 << ") to connect in simple singleplayer mode" << std::endl;
 334                 DenyAccess_Legacy(pkt->getPeerId(), L"Running in simple singleplayer mode.");
 335                 return;
 336         }
 337
 338         // First byte after command is maximum supported
 339         // serialization version
 340         u8 client_max;
 341
 342         *pkt >> client_max;
 343
 344         u8 our_max = SER_FMT_VER_HIGHEST_READ;
 345         // Use the highest version supported by both
 346         int deployed = std::min(client_max, our_max);
 347         // If it's lower than the lowest supported, give up.
 348         if (deployed < SER_FMT_VER_LOWEST)
 349                 deployed = SER_FMT_VER_INVALID;
 350
 351         if (deployed == SER_FMT_VER_INVALID) {
 352                 actionstream << "Server: A mismatched client tried to connect from "
 353                                 << addr_s << std::endl;
 354                 infostream<<"Server: Cannot negotiate serialization version with "
 355                                 << addr_s << std::endl;
 356                 DenyAccess_Legacy(pkt->getPeerId(), std::wstring(
 357                                 L"Your client's version is not supported.\n"
 358                                 L"Server version is ")
 359                                 + narrow_to_wide(g_version_string) + L"."
 360                 );
 361                 return;
 362         }
 363
 364         client->setPendingSerializationVersion(deployed);
 365
 366         /*
 367                 Read and check network protocol version
 368         */
 369
 370         u16 min_net_proto_version = 0;
 371         if (pkt->getSize() >= 1 + PLAYERNAME_SIZE + PASSWORD_SIZE + 2)
 372                 min_net_proto_version = pkt->getU16(1 + PLAYERNAME_SIZE + PASSWORD_SIZE);
 373
 374         // Use same version as minimum and maximum if maximum version field
 375         // doesn't exist (backwards compatibility)
 376         u16 max_net_proto_version = min_net_proto_version;
 377         if (pkt->getSize() >= 1 + PLAYERNAME_SIZE + PASSWORD_SIZE + 2 + 2)
 378                 max_net_proto_version = pkt->getU16(1 + PLAYERNAME_SIZE + PASSWORD_SIZE + 2);
 379
 380         // Start with client's maximum version
 381         u16 net_proto_version = max_net_proto_version;
 382
 383         // Figure out a working version if it is possible at all
 384         if (max_net_proto_version >= SERVER_PROTOCOL_VERSION_MIN ||
 385                         min_net_proto_version <= SERVER_PROTOCOL_VERSION_MAX) {
 386                 // If maximum is larger than our maximum, go with our maximum
 387                 if (max_net_proto_version > SERVER_PROTOCOL_VERSION_MAX)
 388                         net_proto_version = SERVER_PROTOCOL_VERSION_MAX;
 389                 // Else go with client's maximum
 390                 else
 391                         net_proto_version = max_net_proto_version;
 392         }
 393
 394         // The client will send up to date init packet, ignore this one
 395         if (net_proto_version >= 25)
 396                 return;
 397
 398         verbosestream << "Server: " << addr_s << ": Protocol version: min: "
 399                         << min_net_proto_version << ", max: " << max_net_proto_version
 400                         << ", chosen: " << net_proto_version << std::endl;
 401
 402         client->net_proto_version = net_proto_version;
 403
 404         if (net_proto_version < SERVER_PROTOCOL_VERSION_MIN ||
 405                         net_proto_version > SERVER_PROTOCOL_VERSION_MAX) {
 406                 actionstream << "Server: A mismatched client tried to connect from "
 407                                 << addr_s << std::endl;
 408                 DenyAccess_Legacy(pkt->getPeerId(), std::wstring(
 409                                 L"Your client's version is not supported.\n"
 410                                 L"Server version is ")
 411                                 + narrow_to_wide(g_version_string) + L",\n"
 412                                 + L"server's PROTOCOL_VERSION is "
 413                                 + narrow_to_wide(itos(SERVER_PROTOCOL_VERSION_MIN))
 414                                 + L"..."
 415                                 + narrow_to_wide(itos(SERVER_PROTOCOL_VERSION_MAX))
 416                                 + L", client's PROTOCOL_VERSION is "
 417                                 + narrow_to_wide(itos(min_net_proto_version))
 418                                 + L"..."
 419                                 + narrow_to_wide(itos(max_net_proto_version))
 420                 );
 421                 return;
 422         }
 423
 424         if (g_settings->getBool("strict_protocol_version_checking")) {
 425                 if (net_proto_version != LATEST_PROTOCOL_VERSION) {
 426                         actionstream << "Server: A mismatched (strict) client tried to "
 427                                         << "connect from " << addr_s << std::endl;
 428                         DenyAccess_Legacy(pkt->getPeerId(), std::wstring(
 429                                         L"Your client's version is not supported.\n"
 430                                         L"Server version is ")
 431                                         + narrow_to_wide(g_version_string) + L",\n"
 432                                         + L"server's PROTOCOL_VERSION (strict) is "
 433                                         + narrow_to_wide(itos(LATEST_PROTOCOL_VERSION))
 434                                         + L", client's PROTOCOL_VERSION is "
 435                                         + narrow_to_wide(itos(min_net_proto_version))
 436                                         + L"..."
 437                                         + narrow_to_wide(itos(max_net_proto_version))
 438                         );
 439                         return;
 440                 }
 441         }
 442
 443         /*
 444                 Set up player
 445         */
 446         char playername[PLAYERNAME_SIZE];
 447         unsigned int playername_length = 0;
 448         for (; playername_length < PLAYERNAME_SIZE; playername_length++ ) {
 449                 playername[playername_length] = pkt->getChar(1+playername_length);
 450                 if (pkt->getChar(1+playername_length) == 0)
 451                         break;
 452         }
 453
 454         if (playername_length == PLAYERNAME_SIZE) {
 455                 actionstream << "Server: Player with name exceeding max length "
 456                                 << "tried to connect from " << addr_s << std::endl;
 457                 DenyAccess_Legacy(pkt->getPeerId(), L"Name too long");
 458                 return;
 459         }
 460
 461
 462         if (playername[0]=='\0') {
 463                 actionstream << "Server: Player with an empty name "
 464                                 << "tried to connect from " << addr_s << std::endl;
 465                 DenyAccess_Legacy(pkt->getPeerId(), L"Empty name");
 466                 return;
 467         }
 468
 469         if (string_allowed(playername, PLAYERNAME_ALLOWED_CHARS) == false) {
 470                 actionstream << "Server: Player with an invalid name "
 471                                 << "tried to connect from " << addr_s << std::endl;
 472                 DenyAccess_Legacy(pkt->getPeerId(), L"Name contains unallowed characters");
 473                 return;
 474         }
 475
 476         if (!isSingleplayer() && strcasecmp(playername, "singleplayer") == 0) {
 477                 actionstream << "Server: Player with the name \"singleplayer\" "
 478                                 << "tried to connect from " << addr_s << std::endl;
 479                 DenyAccess_Legacy(pkt->getPeerId(), L"Name is not allowed");
 480                 return;
 481         }
 482
 483         {
 484                 std::string reason;
 485                 if (m_script->on_prejoinplayer(playername, addr_s, &reason)) {
 486                         actionstream << "Server: Player with the name \"" << playername << "\" "
 487                                         << "tried to connect from " << addr_s << " "
 488                                         << "but it was disallowed for the following reason: "
 489                                         << reason << std::endl;
 490                         DenyAccess_Legacy(pkt->getPeerId(), narrow_to_wide(reason.c_str()));
 491                         return;
 492                 }
 493         }
 494
 495         infostream<<"Server: New connection: \""<<playername<<"\" from "
 496                         <<addr_s<<" (peer_id="<<pkt->getPeerId()<<")"<<std::endl;
 497
 498         // Get password
 499         char given_password[PASSWORD_SIZE];
 500         if (pkt->getSize() < 1 + PLAYERNAME_SIZE + PASSWORD_SIZE) {
 501                 // old version - assume blank password
 502                 given_password[0] = 0;
 503         }
 504         else {
 505                 for (u16 i = 0; i < PASSWORD_SIZE - 1; i++) {
 506                         given_password[i] = pkt->getChar(21 + i);
 507                 }
 508                 given_password[PASSWORD_SIZE - 1] = 0;
 509         }
 510
 511         if (!base64_is_valid(given_password)) {
 512                 actionstream << "Server: " << playername
 513                                 << " supplied invalid password hash" << std::endl;
 514                 DenyAccess_Legacy(pkt->getPeerId(), L"Invalid password hash");
 515                 return;
 516         }
 517
 518         // Enforce user limit.
 519         // Don't enforce for users that have some admin right
 520         if (m_clients.getClientIDs(CS_Created).size() >= g_settings->getU16("max_users") &&
 521                         !checkPriv(playername, "server") &&
 522                         !checkPriv(playername, "ban") &&
 523                         !checkPriv(playername, "privs") &&
 524                         !checkPriv(playername, "password") &&
 525                         playername != g_settings->get("name")) {
 526                 actionstream << "Server: " << playername << " tried to join, but there"
 527                                 << " are already max_users="
 528                                 << g_settings->getU16("max_users") << " players." << std::endl;
 529                 DenyAccess_Legacy(pkt->getPeerId(), L"Too many users.");
 530                 return;
 531         }
 532
 533         std::string checkpwd; // Password hash to check against
 534         bool has_auth = m_script->getAuth(playername, &checkpwd, NULL);
 535
 536         // If no authentication info exists for user, create it
 537         if (!has_auth) {
 538                 if (!isSingleplayer() &&
 539                                 g_settings->getBool("disallow_empty_password") &&
 540                                 std::string(given_password) == "") {
 541                         actionstream << "Server: " << playername
 542                                         << " supplied empty password" << std::endl;
 543                         DenyAccess_Legacy(pkt->getPeerId(), L"Empty passwords are "
 544                                         L"disallowed. Set a password and try again.");
 545                         return;
 546                 }
 547                 std::string raw_default_password =
 548                         g_settings->get("default_password");
 549                 std::string initial_password =
 550                         translatePassword(playername, raw_default_password);
 551
 552                 // If default_password is empty, allow any initial password
 553                 if (raw_default_password.length() == 0)
 554                         initial_password = given_password;
 555
 556                 m_script->createAuth(playername, initial_password);
 557         }
 558
 559         has_auth = m_script->getAuth(playername, &checkpwd, NULL);
 560
 561         if (!has_auth) {
 562                 actionstream << "Server: " << playername << " cannot be authenticated"
 563                                 << " (auth handler does not work?)" << std::endl;
 564                 DenyAccess_Legacy(pkt->getPeerId(), L"Not allowed to login");
 565                 return;
 566         }
 567
 568         if (given_password != checkpwd) {
 569                 actionstream << "Server: " << playername << " supplied wrong password"
 570                                 << std::endl;
 571                 DenyAccess_Legacy(pkt->getPeerId(), L"Wrong password");
 572                 return;
 573         }
 574
 575         RemotePlayer *player =
 576                         static_cast<RemotePlayer*>(m_env->getPlayer(playername));
 577
 578         if (player && player->peer_id != 0) {
 579                 errorstream << "Server: " << playername << ": Failed to emerge player"
 580                                 << " (player allocated to an another client)" << std::endl;
 581                 DenyAccess_Legacy(pkt->getPeerId(), L"Another client is connected with this "
 582                                 L"name. If your client closed unexpectedly, try again in "
 583                                 L"a minute.");
 584         }
 585
 586         m_clients.setPlayerName(pkt->getPeerId(), playername);
 587
 588         /*
 589                 Answer with a TOCLIENT_INIT
 590         */
 591
 592         NetworkPacket resp_pkt(TOCLIENT_INIT_LEGACY, 1 + 6 + 8 + 4,
 593                         pkt->getPeerId());
 594
 595         resp_pkt << (u8) deployed << (v3s16) floatToInt(v3f(0,0,0), BS)
 596                         << (u64) m_env->getServerMap().getSeed()
 597                         << g_settings->getFloat("dedicated_server_step");
 598
 599         Send(&resp_pkt);
 600         m_clients.event(pkt->getPeerId(), CSE_InitLegacy);
 601 }
 602
 603 void Server::handleCommand_Init2(NetworkPacket* pkt)
 604 {
 605         verbosestream << "Server: Got TOSERVER_INIT2 from "
 606                         << pkt->getPeerId() << std::endl;
 607
 608         m_clients.event(pkt->getPeerId(), CSE_GotInit2);
 609         u16 protocol_version = m_clients.getProtocolVersion(pkt->getPeerId());
 610
 611
 612         ///// begin compatibility code
 613         PlayerSAO* playersao = NULL;
 614         if (protocol_version <= 22) {
 615                 playersao = StageTwoClientInit(pkt->getPeerId());
 616
 617                 if (playersao == NULL) {
 618                         actionstream
 619                                 << "TOSERVER_INIT2 stage 2 client init failed for peer "
 620                                 << pkt->getPeerId() << std::endl;
 621                         return;
 622                 }
 623         }
 624         ///// end compatibility code
 625
 626         /*
 627                 Send some initialization data
 628         */
 629
 630         infostream << "Server: Sending content to "
 631                         << getPlayerName(pkt->getPeerId()) << std::endl;
 632
 633         // Send player movement settings
 634         SendMovement(pkt->getPeerId());
 635
 636         // Send item definitions
 637         SendItemDef(pkt->getPeerId(), m_itemdef, protocol_version);
 638
 639         // Send node definitions
 640         SendNodeDef(pkt->getPeerId(), m_nodedef, protocol_version);
 641
 642         m_clients.event(pkt->getPeerId(), CSE_SetDefinitionsSent);
 643
 644         // Send media announcement
 645         sendMediaAnnouncement(pkt->getPeerId());
 646
 647         // Send detached inventories
 648         sendDetachedInventories(pkt->getPeerId());
 649
 650         // Send time of day
 651         u16 time = m_env->getTimeOfDay();
 652         float time_speed = g_settings->getFloat("time_speed");
 653         SendTimeOfDay(pkt->getPeerId(), time, time_speed);
 654
 655         ///// begin compatibility code
 656         if (protocol_version <= 22) {
 657                 m_clients.event(pkt->getPeerId(), CSE_SetClientReady);
 658                 m_script->on_joinplayer(playersao);
 659         }
 660         ///// end compatibility code
 661
 662         // Warnings about protocol version can be issued here
 663         if (getClient(pkt->getPeerId())->net_proto_version < LATEST_PROTOCOL_VERSION) {
 664                 SendChatMessage(pkt->getPeerId(), L"# Server: WARNING: YOUR CLIENT'S "
 665                                 L"VERSION MAY NOT BE FULLY COMPATIBLE WITH THIS SERVER!");
 666         }
 667 }
 668
 669 void Server::handleCommand_RequestMedia(NetworkPacket* pkt)
 670 {
 671         std::vector<std::string> tosend;
 672         u16 numfiles;
 673
 674         *pkt >> numfiles;
 675
 676         infostream << "Sending " << numfiles << " files to "
 677                         << getPlayerName(pkt->getPeerId()) << std::endl;
 678         verbosestream << "TOSERVER_REQUEST_MEDIA: " << std::endl;
 679
 680         for (u16 i = 0; i < numfiles; i++) {
 681                 std::string name;
 682
 683                 *pkt >> name;
 684
 685                 tosend.push_back(name);
 686                 verbosestream << "TOSERVER_REQUEST_MEDIA: requested file "
 687                                 << name << std::endl;
 688         }
 689
 690         sendRequestedMedia(pkt->getPeerId(), tosend);
 691 }
 692
 693 void Server::handleCommand_ReceivedMedia(NetworkPacket* pkt)
 694 {
 695 }
 696
 697 void Server::handleCommand_ClientReady(NetworkPacket* pkt)
 698 {
 699         u16 peer_id = pkt->getPeerId();
 700         u16 peer_proto_ver = getClient(peer_id, CS_InitDone)->net_proto_version;
 701
 702         // clients <= protocol version 22 did not send ready message,
 703         // they're already initialized
 704         if (peer_proto_ver <= 22) {
 705                 infostream << "Client sent message not expected by a "
 706                         << "client using protocol version <= 22,"
 707                         << "disconnecting peer_id: " << peer_id << std::endl;
 708                 m_con.DisconnectPeer(peer_id);
 709                 return;
 710         }
 711
 712         PlayerSAO* playersao = StageTwoClientInit(peer_id);
 713
 714         if (playersao == NULL) {
 715                 actionstream
 716                         << "TOSERVER_CLIENT_READY stage 2 client init failed for peer_id: "
 717                         << peer_id << std::endl;
 718                 m_con.DisconnectPeer(peer_id);
 719                 return;
 720         }
 721
 722
 723         if (pkt->getSize() < 8) {
 724                 errorstream
 725                         << "TOSERVER_CLIENT_READY client sent inconsistent data, disconnecting peer_id: "
 726                         << peer_id << std::endl;
 727                 m_con.DisconnectPeer(peer_id);
 728                 return;
 729         }
 730
 731         u8 major_ver, minor_ver, patch_ver, reserved;
 732         std::string full_ver;
 733         *pkt >> major_ver >> minor_ver >> patch_ver >> reserved >> full_ver;
 734
 735         m_clients.setClientVersion(
 736                         peer_id, major_ver, minor_ver, patch_ver,
 737                         full_ver);
 738
 739         m_clients.event(peer_id, CSE_SetClientReady);
 740         m_script->on_joinplayer(playersao);
 741 }
 742
 743 void Server::handleCommand_GotBlocks(NetworkPacket* pkt)
 744 {
 745         if (pkt->getSize() < 1)
 746                 return;
 747
 748         /*
 749                 [0] u16 command
 750                 [2] u8 count
 751                 [3] v3s16 pos_0
 752                 [3+6] v3s16 pos_1
 753                 ...
 754         */
 755
 756         u8 count;
 757         *pkt >> count;
 758
 759         RemoteClient *client = getClient(pkt->getPeerId());
 760
 761         for (u16 i = 0; i < count; i++) {
 762                 if ((s16)pkt->getSize() < 1 + (i + 1) * 6)
 763                         throw con::InvalidIncomingDataException
 764                                 ("GOTBLOCKS length is too short");
 765                 v3s16 p;
 766
 767                 *pkt >> p;
 768
 769                 client->GotBlock(p);
 770         }
 771 }
 772
 773 void Server::handleCommand_PlayerPos(NetworkPacket* pkt)
 774 {
 775         if (pkt->getSize() < 12 + 12 + 4 + 4)
 776                 return;
 777
 778         v3s32 ps, ss;
 779         s32 f32pitch, f32yaw;
 780
 781         *pkt >> ps;
 782         *pkt >> ss;
 783         *pkt >> f32pitch;
 784         *pkt >> f32yaw;
 785
 786         f32 pitch = (f32)f32pitch / 100.0;
 787         f32 yaw = (f32)f32yaw / 100.0;
 788         u32 keyPressed = 0;
 789
 790         if (pkt->getSize() >= 12 + 12 + 4 + 4 + 4)
 791                 *pkt >> keyPressed;
 792
 793         v3f position((f32)ps.X / 100.0, (f32)ps.Y / 100.0, (f32)ps.Z / 100.0);
 794         v3f speed((f32)ss.X / 100.0, (f32)ss.Y / 100.0, (f32)ss.Z / 100.0);
 795
 796         pitch = modulo360f(pitch);
 797         yaw = modulo360f(yaw);
 798
 799         Player *player = m_env->getPlayer(pkt->getPeerId());
 800         if (player == NULL) {
 801                 errorstream << "Server::ProcessData(): Canceling: "
 802                                 "No player for peer_id=" << pkt->getPeerId()
 803                                 << " disconnecting peer!" << std::endl;
 804                 m_con.DisconnectPeer(pkt->getPeerId());
 805                 return;
 806         }
 807
 808         // If player is dead we don't care of this packet
 809         if (player->isDead()) {
 810                 verbosestream << "TOSERVER_PLAYERPOS: " << player->getName()
 811                         << " is dead. Ignoring packet";
 812                 return;
 813         }
 814
 815         PlayerSAO *playersao = player->getPlayerSAO();
 816         if (playersao == NULL) {
 817                 errorstream << "Server::ProcessData(): Canceling: "
 818                                 "No player object for peer_id=" << pkt->getPeerId()
 819                                 << " disconnecting peer!" << std::endl;
 820                 m_con.DisconnectPeer(pkt->getPeerId());
 821                 return;
 822         }
 823
 824         player->setPosition(position);
 825         player->setSpeed(speed);
 826         player->setPitch(pitch);
 827         player->setYaw(yaw);
 828         player->keyPressed = keyPressed;
 829         player->control.up = (keyPressed & 1);
 830         player->control.down = (keyPressed & 2);
 831         player->control.left = (keyPressed & 4);
 832         player->control.right = (keyPressed & 8);
 833         player->control.jump = (keyPressed & 16);
 834         player->control.aux1 = (keyPressed & 32);
 835         player->control.sneak = (keyPressed & 64);
 836         player->control.LMB = (keyPressed & 128);
 837         player->control.RMB = (keyPressed & 256);
 838
 839         if (playersao->checkMovementCheat()) {
 840                 // Call callbacks
 841                 m_script->on_cheat(playersao, "moved_too_fast");
 842                 SendMovePlayer(pkt->getPeerId());
 843         }
 844 }
 845
 846 void Server::handleCommand_DeletedBlocks(NetworkPacket* pkt)
 847 {
 848         if (pkt->getSize() < 1)
 849                 return;
 850
 851         /*
 852                 [0] u16 command
 853                 [2] u8 count
 854                 [3] v3s16 pos_0
 855                 [3+6] v3s16 pos_1
 856                 ...
 857         */
 858
 859         u8 count;
 860         *pkt >> count;
 861
 862         RemoteClient *client = getClient(pkt->getPeerId());
 863
 864         for (u16 i = 0; i < count; i++) {
 865                 if ((s16)pkt->getSize() < 1 + (i + 1) * 6)
 866                         throw con::InvalidIncomingDataException
 867                                 ("DELETEDBLOCKS length is too short");
 868                 v3s16 p;
 869                 *pkt >> p;
 870
 871                 client->SetBlockNotSent(p);
 872         }
 873 }
 874
 875 void Server::handleCommand_InventoryAction(NetworkPacket* pkt)
 876 {
 877         Player *player = m_env->getPlayer(pkt->getPeerId());
 878         if (player == NULL) {
 879                 errorstream << "Server::ProcessData(): Canceling: "
 880                                 "No player for peer_id=" << pkt->getPeerId()
 881                                 << " disconnecting peer!" << std::endl;
 882                 m_con.DisconnectPeer(pkt->getPeerId());
 883                 return;
 884         }
 885
 886         PlayerSAO *playersao = player->getPlayerSAO();
 887         if (playersao == NULL) {
 888                 errorstream << "Server::ProcessData(): Canceling: "
 889                                 "No player object for peer_id=" << pkt->getPeerId()
 890                                 << " disconnecting peer!" << std::endl;
 891                 m_con.DisconnectPeer(pkt->getPeerId());
 892                 return;
 893         }
 894
 895         // Strip command and create a stream
 896         std::string datastring(pkt->getString(0), pkt->getSize());
 897         verbosestream << "TOSERVER_INVENTORY_ACTION: data=" << datastring
 898                 << std::endl;
 899         std::istringstream is(datastring, std::ios_base::binary);
 900         // Create an action
 901         InventoryAction *a = InventoryAction::deSerialize(is);
 902         if (a == NULL) {
 903                 infostream << "TOSERVER_INVENTORY_ACTION: "
 904                                 << "InventoryAction::deSerialize() returned NULL"
 905                                 << std::endl;
 906                 return;
 907         }
 908
 909         // If something goes wrong, this player is to blame
 910         RollbackScopeActor rollback_scope(m_rollback,
 911                         std::string("player:")+player->getName());
 912
 913         /*
 914                 Note: Always set inventory not sent, to repair cases
 915                 where the client made a bad prediction.
 916         */
 917
 918         /*
 919                 Handle restrictions and special cases of the move action
 920         */
 921         if (a->getType() == IACTION_MOVE) {
 922                 IMoveAction *ma = (IMoveAction*)a;
 923
 924                 ma->from_inv.applyCurrentPlayer(player->getName());
 925                 ma->to_inv.applyCurrentPlayer(player->getName());
 926
 927                 setInventoryModified(ma->from_inv, false);
 928                 setInventoryModified(ma->to_inv, false);
 929
 930                 bool from_inv_is_current_player =
 931                         (ma->from_inv.type == InventoryLocation::PLAYER) &&
 932                         (ma->from_inv.name == player->getName());
 933
 934                 bool to_inv_is_current_player =
 935                         (ma->to_inv.type == InventoryLocation::PLAYER) &&
 936                         (ma->to_inv.name == player->getName());
 937
 938                 /*
 939                         Disable moving items out of craftpreview
 940                 */
 941                 if (ma->from_list == "craftpreview") {
 942                         infostream << "Ignoring IMoveAction from "
 943                                         << (ma->from_inv.dump()) << ":" << ma->from_list
 944                                         << " to " << (ma->to_inv.dump()) << ":" << ma->to_list
 945                                         << " because src is " << ma->from_list << std::endl;
 946                         delete a;
 947                         return;
 948                 }
 949
 950                 /*
 951                         Disable moving items into craftresult and craftpreview
 952                 */
 953                 if (ma->to_list == "craftpreview" || ma->to_list == "craftresult") {
 954                         infostream << "Ignoring IMoveAction from "
 955                                         << (ma->from_inv.dump()) << ":" << ma->from_list
 956                                         << " to " << (ma->to_inv.dump()) << ":" << ma->to_list
 957                                         << " because dst is " << ma->to_list << std::endl;
 958                         delete a;
 959                         return;
 960                 }
 961
 962                 // Disallow moving items in elsewhere than player's inventory
 963                 // if not allowed to interact
 964                 if (!checkPriv(player->getName(), "interact") &&
 965                                 (!from_inv_is_current_player ||
 966                                 !to_inv_is_current_player)) {
 967                         infostream << "Cannot move outside of player's inventory: "
 968                                         << "No interact privilege" << std::endl;
 969                         delete a;
 970                         return;
 971                 }
 972         }
 973         /*
 974                 Handle restrictions and special cases of the drop action
 975         */
 976         else if (a->getType() == IACTION_DROP) {
 977                 IDropAction *da = (IDropAction*)a;
 978
 979                 da->from_inv.applyCurrentPlayer(player->getName());
 980
 981                 setInventoryModified(da->from_inv, false);
 982
 983                 /*
 984                         Disable dropping items out of craftpreview
 985                 */
 986                 if (da->from_list == "craftpreview") {
 987                         infostream << "Ignoring IDropAction from "
 988                                         << (da->from_inv.dump()) << ":" << da->from_list
 989                                         << " because src is " << da->from_list << std::endl;
 990                         delete a;
 991                         return;
 992                 }
 993
 994                 // Disallow dropping items if not allowed to interact
 995                 if (!checkPriv(player->getName(), "interact")) {
 996                         delete a;
 997                         return;
 998                 }
 999         }
1000         /*
1001                 Handle restrictions and special cases of the craft action
1002         */
1003         else if (a->getType() == IACTION_CRAFT) {
1004                 ICraftAction *ca = (ICraftAction*)a;
1005
1006                 ca->craft_inv.applyCurrentPlayer(player->getName());
1007
1008                 setInventoryModified(ca->craft_inv, false);
1009
1010                 //bool craft_inv_is_current_player =
1011                 //      (ca->craft_inv.type == InventoryLocation::PLAYER) &&
1012                 //      (ca->craft_inv.name == player->getName());
1013
1014                 // Disallow crafting if not allowed to interact
1015                 if (!checkPriv(player->getName(), "interact")) {
1016                         infostream << "Cannot craft: "
1017                                         << "No interact privilege" << std::endl;
1018                         delete a;
1019                         return;
1020                 }
1021         }
1022
1023         // Do the action
1024         a->apply(this, playersao, this);
1025         // Eat the action
1026         delete a;
1027
1028         SendInventory(playersao);
1029 }
1030
1031 void Server::handleCommand_ChatMessage(NetworkPacket* pkt)
1032 {
1033         /*
1034                 u16 command
1035                 u16 length
1036                 wstring message
1037         */
1038         u16 len;
1039         *pkt >> len;
1040
1041         std::wstring message;
1042         for (u16 i = 0; i < len; i++) {
1043                 u16 tmp_wchar;
1044                 *pkt >> tmp_wchar;
1045
1046                 message += (wchar_t)tmp_wchar;
1047         }
1048
1049         Player *player = m_env->getPlayer(pkt->getPeerId());
1050         if (player == NULL) {
1051                 errorstream << "Server::ProcessData(): Canceling: "
1052                                 "No player for peer_id=" << pkt->getPeerId()
1053                                 << " disconnecting peer!" << std::endl;
1054                 m_con.DisconnectPeer(pkt->getPeerId());
1055                 return;
1056         }
1057
1058         // If something goes wrong, this player is to blame
1059         RollbackScopeActor rollback_scope(m_rollback,
1060                         std::string("player:")+player->getName());
1061
1062         // Get player name of this client
1063         std::wstring name = narrow_to_wide(player->getName());
1064
1065         // Run script hook
1066         bool ate = m_script->on_chat_message(player->getName(),
1067                         wide_to_narrow(message));
1068         // If script ate the message, don't proceed
1069         if (ate)
1070                 return;
1071
1072         // Line to send to players
1073         std::wstring line;
1074         // Whether to send to the player that sent the line
1075         bool send_to_sender_only = false;
1076
1077         // Commands are implemented in Lua, so only catch invalid
1078         // commands that were not "eaten" and send an error back
1079         if (message[0] == L'/') {
1080                 message = message.substr(1);
1081                 send_to_sender_only = true;
1082                 if (message.length() == 0)
1083                         line += L"-!- Empty command";
1084                 else
1085                         line += L"-!- Invalid command: " + str_split(message, L' ')[0];
1086         }
1087         else {
1088                 if (checkPriv(player->getName(), "shout")) {
1089                         line += L"<";
1090                         line += name;
1091                         line += L"> ";
1092                         line += message;
1093                 } else {
1094                         line += L"-!- You don't have permission to shout.";
1095                         send_to_sender_only = true;
1096                 }
1097         }
1098
1099         if (line != L"")
1100         {
1101                 /*
1102                         Send the message to sender
1103                 */
1104                 if (send_to_sender_only) {
1105                         SendChatMessage(pkt->getPeerId(), line);
1106                 }
1107                 /*
1108                         Send the message to others
1109                 */
1110                 else {
1111                         actionstream << "CHAT: " << wide_to_narrow(line)<<std::endl;
1112
1113                         std::vector<u16> clients = m_clients.getClientIDs();
1114
1115                         for (std::vector<u16>::iterator i = clients.begin();
1116                                 i != clients.end(); ++i) {
1117                                 if (*i != pkt->getPeerId())
1118                                         SendChatMessage(*i, line);
1119                         }
1120                 }
1121         }
1122 }
1123
1124 void Server::handleCommand_Damage(NetworkPacket* pkt)
1125 {
1126         u8 damage;
1127
1128         *pkt >> damage;
1129
1130         Player *player = m_env->getPlayer(pkt->getPeerId());
1131         if (player == NULL) {
1132                 errorstream << "Server::ProcessData(): Canceling: "
1133                                 "No player for peer_id=" << pkt->getPeerId()
1134                                 << " disconnecting peer!" << std::endl;
1135                 m_con.DisconnectPeer(pkt->getPeerId());
1136                 return;
1137         }
1138
1139         PlayerSAO *playersao = player->getPlayerSAO();
1140         if (playersao == NULL) {
1141                 errorstream << "Server::ProcessData(): Canceling: "
1142                                 "No player object for peer_id=" << pkt->getPeerId()
1143                                 << " disconnecting peer!" << std::endl;
1144                 m_con.DisconnectPeer(pkt->getPeerId());
1145                 return;
1146         }
1147
1148         if (g_settings->getBool("enable_damage")) {
1149                 actionstream << player->getName() << " damaged by "
1150                                 << (int)damage << " hp at " << PP(player->getPosition() / BS)
1151                                 << std::endl;
1152
1153                 playersao->setHP(playersao->getHP() - damage);
1154                 SendPlayerHPOrDie(playersao->getPeerID(), playersao->getHP() == 0);
1155         }
1156 }
1157
1158 void Server::handleCommand_Breath(NetworkPacket* pkt)
1159 {
1160         u16 breath;
1161
1162         *pkt >> breath;
1163
1164         Player *player = m_env->getPlayer(pkt->getPeerId());
1165         if (player == NULL) {
1166                 errorstream << "Server::ProcessData(): Canceling: "
1167                                 "No player for peer_id=" << pkt->getPeerId()
1168                                 << " disconnecting peer!" << std::endl;
1169                 m_con.DisconnectPeer(pkt->getPeerId());
1170                 return;
1171         }
1172
1173         /*
1174          * If player is dead, we don't need to update the breath
1175          * He is dead !
1176          */
1177         if (player->isDead()) {
1178                 verbosestream << "TOSERVER_BREATH: " << player->getName()
1179                         << " is dead. Ignoring packet";
1180                 return;
1181         }
1182
1183
1184         PlayerSAO *playersao = player->getPlayerSAO();
1185         if (playersao == NULL) {
1186                 errorstream << "Server::ProcessData(): Canceling: "
1187                                 "No player object for peer_id=" << pkt->getPeerId()
1188                                 << " disconnecting peer!" << std::endl;
1189                 m_con.DisconnectPeer(pkt->getPeerId());
1190                 return;
1191         }
1192
1193         playersao->setBreath(breath);
1194         SendPlayerBreath(pkt->getPeerId());
1195 }
1196
1197 void Server::handleCommand_Password(NetworkPacket* pkt)
1198 {
1199         if (pkt->getSize() != PASSWORD_SIZE * 2)
1200                 return;
1201
1202         std::string oldpwd;
1203         std::string newpwd;
1204
1205         // Deny for clients using the new protocol
1206         RemoteClient* client = getClient(pkt->getPeerId(), CS_Created);
1207         if (client->net_proto_version >= 25) {
1208                 infostream << "Server::handleCommand_Password(): Denying change: "
1209                         << " Client protocol version for peer_id=" << pkt->getPeerId()
1210                         << " too new!" << std::endl;
1211                 return;
1212         }
1213
1214         for (u16 i = 0; i < PASSWORD_SIZE - 1; i++) {
1215                 char c = pkt->getChar(i);
1216                 if (c == 0)
1217                         break;
1218                 oldpwd += c;
1219         }
1220
1221         for (u16 i = 0; i < PASSWORD_SIZE - 1; i++) {
1222                 char c = pkt->getChar(PASSWORD_SIZE + i);
1223                 if (c == 0)
1224                         break;
1225                 newpwd += c;
1226         }
1227
1228         Player *player = m_env->getPlayer(pkt->getPeerId());
1229         if (player == NULL) {
1230                 errorstream << "Server::ProcessData(): Canceling: "
1231                                 "No player for peer_id=" << pkt->getPeerId()
1232                                 << " disconnecting peer!" << std::endl;
1233                 m_con.DisconnectPeer(pkt->getPeerId());
1234                 return;
1235         }
1236
1237         if (!base64_is_valid(newpwd)) {
1238                 infostream<<"Server: " << player->getName() <<
1239                                 " supplied invalid password hash" << std::endl;
1240                 // Wrong old password supplied!!
1241                 SendChatMessage(pkt->getPeerId(), L"Invalid new password hash supplied. Password NOT changed.");
1242                 return;
1243         }
1244
1245         infostream << "Server: Client requests a password change from "
1246                         << "'" << oldpwd << "' to '" << newpwd << "'" << std::endl;
1247
1248         std::string playername = player->getName();
1249
1250         std::string checkpwd;
1251         m_script->getAuth(playername, &checkpwd, NULL);
1252
1253         if (oldpwd != checkpwd) {
1254                 infostream << "Server: invalid old password" << std::endl;
1255                 // Wrong old password supplied!!
1256                 SendChatMessage(pkt->getPeerId(), L"Invalid old password supplied. Password NOT changed.");
1257                 return;
1258         }
1259
1260         bool success = m_script->setPassword(playername, newpwd);
1261         if (success) {
1262                 actionstream << player->getName() << " changes password" << std::endl;
1263                 SendChatMessage(pkt->getPeerId(), L"Password change successful.");
1264         } else {
1265                 actionstream << player->getName() << " tries to change password but "
1266                                 << "it fails" << std::endl;
1267                 SendChatMessage(pkt->getPeerId(), L"Password change failed or unavailable.");
1268         }
1269 }
1270
1271 void Server::handleCommand_PlayerItem(NetworkPacket* pkt)
1272 {
1273         if (pkt->getSize() < 2)
1274                 return;
1275
1276         Player *player = m_env->getPlayer(pkt->getPeerId());
1277         if (player == NULL) {
1278                 errorstream << "Server::ProcessData(): Canceling: "
1279                                 "No player for peer_id=" << pkt->getPeerId()
1280                                 << " disconnecting peer!" << std::endl;
1281                 m_con.DisconnectPeer(pkt->getPeerId());
1282                 return;
1283         }
1284
1285         PlayerSAO *playersao = player->getPlayerSAO();
1286         if (playersao == NULL) {
1287                 errorstream << "Server::ProcessData(): Canceling: "
1288                                 "No player object for peer_id=" << pkt->getPeerId()
1289                                 << " disconnecting peer!" << std::endl;
1290                 m_con.DisconnectPeer(pkt->getPeerId());
1291                 return;
1292         }
1293
1294         u16 item;
1295
1296         *pkt >> item;
1297
1298         playersao->setWieldIndex(item);
1299 }
1300
1301 void Server::handleCommand_Respawn(NetworkPacket* pkt)
1302 {
1303         Player *player = m_env->getPlayer(pkt->getPeerId());
1304         if (player == NULL) {
1305                 errorstream << "Server::ProcessData(): Canceling: "
1306                                 "No player for peer_id=" << pkt->getPeerId()
1307                                 << " disconnecting peer!" << std::endl;
1308                 m_con.DisconnectPeer(pkt->getPeerId());
1309                 return;
1310         }
1311
1312         if (!player->isDead())
1313                 return;
1314
1315         RespawnPlayer(pkt->getPeerId());
1316
1317         actionstream << player->getName() << " respawns at "
1318                         << PP(player->getPosition()/BS) << std::endl;
1319
1320         // ActiveObject is added to environment in AsyncRunStep after
1321         // the previous addition has been successfully removed
1322 }
1323
1324 void Server::handleCommand_Interact(NetworkPacket* pkt)
1325 {
1326         std::string datastring(pkt->getString(0), pkt->getSize());
1327         std::istringstream is(datastring, std::ios_base::binary);
1328
1329         /*
1330                 [0] u16 command
1331                 [2] u8 action
1332                 [3] u16 item
1333                 [5] u32 length of the next item
1334                 [9] serialized PointedThing
1335                 actions:
1336                 0: start digging (from undersurface) or use
1337                 1: stop digging (all parameters ignored)
1338                 2: digging completed
1339                 3: place block or item (to abovesurface)
1340                 4: use item
1341         */
1342         u8 action = readU8(is);
1343         u16 item_i = readU16(is);
1344         std::istringstream tmp_is(deSerializeLongString(is), std::ios::binary);
1345         PointedThing pointed;
1346         pointed.deSerialize(tmp_is);
1347
1348         verbosestream << "TOSERVER_INTERACT: action=" << (int)action << ", item="
1349                         << item_i << ", pointed=" << pointed.dump() << std::endl;
1350
1351         Player *player = m_env->getPlayer(pkt->getPeerId());
1352         if (player == NULL) {
1353                 errorstream << "Server::ProcessData(): Canceling: "
1354                                 "No player for peer_id=" << pkt->getPeerId()
1355                                 << " disconnecting peer!" << std::endl;
1356                 m_con.DisconnectPeer(pkt->getPeerId());
1357                 return;
1358         }
1359
1360         PlayerSAO *playersao = player->getPlayerSAO();
1361         if (playersao == NULL) {
1362                 errorstream << "Server::ProcessData(): Canceling: "
1363                                 "No player object for peer_id=" << pkt->getPeerId()
1364                                 << " disconnecting peer!" << std::endl;
1365                 m_con.DisconnectPeer(pkt->getPeerId());
1366                 return;
1367         }
1368
1369         if (player->isDead()) {
1370                 verbosestream << "TOSERVER_INTERACT: " << player->getName()
1371                         << " is dead. Ignoring packet";
1372                 return;
1373         }
1374
1375         v3f player_pos = playersao->getLastGoodPosition();
1376
1377         // Update wielded item
1378         playersao->setWieldIndex(item_i);
1379
1380         // Get pointed to node (undefined if not POINTEDTYPE_NODE)
1381         v3s16 p_under = pointed.node_undersurface;
1382         v3s16 p_above = pointed.node_abovesurface;
1383
1384         // Get pointed to object (NULL if not POINTEDTYPE_OBJECT)
1385         ServerActiveObject *pointed_object = NULL;
1386         if (pointed.type == POINTEDTHING_OBJECT) {
1387                 pointed_object = m_env->getActiveObject(pointed.object_id);
1388                 if (pointed_object == NULL) {
1389                         verbosestream << "TOSERVER_INTERACT: "
1390                                 "pointed object is NULL" << std::endl;
1391                         return;
1392                 }
1393
1394         }
1395
1396         v3f pointed_pos_under = player_pos;
1397         v3f pointed_pos_above = player_pos;
1398         if (pointed.type == POINTEDTHING_NODE) {
1399                 pointed_pos_under = intToFloat(p_under, BS);
1400                 pointed_pos_above = intToFloat(p_above, BS);
1401         }
1402         else if (pointed.type == POINTEDTHING_OBJECT) {
1403                 pointed_pos_under = pointed_object->getBasePosition();
1404                 pointed_pos_above = pointed_pos_under;
1405         }
1406
1407         /*
1408                 Check that target is reasonably close
1409                 (only when digging or placing things)
1410         */
1411         if (action == 0 || action == 2 || action == 3) {
1412                 float d = player_pos.getDistanceFrom(pointed_pos_under);
1413                 float max_d = BS * 14; // Just some large enough value
1414                 if (d > max_d) {
1415                         actionstream << "Player " << player->getName()
1416                                         << " tried to access " << pointed.dump()
1417                                         << " from too far: "
1418                                         << "d=" << d <<", max_d=" << max_d
1419                                         << ". ignoring." << std::endl;
1420                         // Re-send block to revert change on client-side
1421                         RemoteClient *client = getClient(pkt->getPeerId());
1422                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1423                         client->SetBlockNotSent(blockpos);
1424                         // Call callbacks
1425                         m_script->on_cheat(playersao, "interacted_too_far");
1426                         // Do nothing else
1427                         return;
1428                 }
1429         }
1430
1431         /*
1432                 Make sure the player is allowed to do it
1433         */
1434         if (!checkPriv(player->getName(), "interact")) {
1435                 actionstream<<player->getName()<<" attempted to interact with "
1436                                 <<pointed.dump()<<" without 'interact' privilege"
1437                                 <<std::endl;
1438                 // Re-send block to revert change on client-side
1439                 RemoteClient *client = getClient(pkt->getPeerId());
1440                 // Digging completed -> under
1441                 if (action == 2) {
1442                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1443                         client->SetBlockNotSent(blockpos);
1444                 }
1445                 // Placement -> above
1446                 if (action == 3) {
1447                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_above, BS));
1448                         client->SetBlockNotSent(blockpos);
1449                 }
1450                 return;
1451         }
1452
1453         /*
1454                 If something goes wrong, this player is to blame
1455         */
1456         RollbackScopeActor rollback_scope(m_rollback,
1457                         std::string("player:")+player->getName());
1458
1459         /*
1460                 0: start digging or punch object
1461         */
1462         if (action == 0) {
1463                 if (pointed.type == POINTEDTHING_NODE) {
1464                         /*
1465                                 NOTE: This can be used in the future to check if
1466                                 somebody is cheating, by checking the timing.
1467                         */
1468                         MapNode n(CONTENT_IGNORE);
1469                         bool pos_ok;
1470                         n = m_env->getMap().getNodeNoEx(p_under, &pos_ok);
1471                         if (pos_ok)
1472                                 n = m_env->getMap().getNodeNoEx(p_under, &pos_ok);
1473
1474                         if (!pos_ok) {
1475                                 infostream << "Server: Not punching: Node not found."
1476                                                 << " Adding block to emerge queue."
1477                                                 << std::endl;
1478                                 m_emerge->enqueueBlockEmerge(pkt->getPeerId(), getNodeBlockPos(p_above), false);
1479                         }
1480
1481                         if (n.getContent() != CONTENT_IGNORE)
1482                                 m_script->node_on_punch(p_under, n, playersao, pointed);
1483                         // Cheat prevention
1484                         playersao->noCheatDigStart(p_under);
1485                 }
1486                 else if (pointed.type == POINTEDTHING_OBJECT) {
1487                         // Skip if object has been removed
1488                         if (pointed_object->m_removed)
1489                                 return;
1490
1491                         actionstream<<player->getName()<<" punches object "
1492                                         <<pointed.object_id<<": "
1493                                         <<pointed_object->getDescription()<<std::endl;
1494
1495                         ItemStack punchitem = playersao->getWieldedItem();
1496                         ToolCapabilities toolcap =
1497                                         punchitem.getToolCapabilities(m_itemdef);
1498                         v3f dir = (pointed_object->getBasePosition() -
1499                                         (player->getPosition() + player->getEyeOffset())
1500                                                 ).normalize();
1501                         float time_from_last_punch =
1502                                 playersao->resetTimeFromLastPunch();
1503
1504                         s16 src_original_hp = pointed_object->getHP();
1505                         s16 dst_origin_hp = playersao->getHP();
1506
1507                         pointed_object->punch(dir, &toolcap, playersao,
1508                                         time_from_last_punch);
1509
1510                         // If the object is a player and its HP changed
1511                         if (src_original_hp != pointed_object->getHP() &&
1512                                         pointed_object->getType() == ACTIVEOBJECT_TYPE_PLAYER) {
1513                                 SendPlayerHPOrDie(((PlayerSAO*)pointed_object)->getPeerID(),
1514                                                 pointed_object->getHP() == 0);
1515                         }
1516
1517                         // If the puncher is a player and its HP changed
1518                         if (dst_origin_hp != playersao->getHP()) {
1519                                 SendPlayerHPOrDie(playersao->getPeerID(), playersao->getHP() == 0);
1520                         }
1521                 }
1522
1523         } // action == 0
1524
1525         /*
1526                 1: stop digging
1527         */
1528         else if (action == 1) {
1529         } // action == 1
1530
1531         /*
1532                 2: Digging completed
1533         */
1534         else if (action == 2) {
1535                 // Only digging of nodes
1536                 if (pointed.type == POINTEDTHING_NODE) {
1537                         bool pos_ok;
1538                         MapNode n = m_env->getMap().getNodeNoEx(p_under, &pos_ok);
1539                         if (!pos_ok) {
1540                                 infostream << "Server: Not finishing digging: Node not found."
1541                                                    << " Adding block to emerge queue."
1542                                                    << std::endl;
1543                                 m_emerge->enqueueBlockEmerge(pkt->getPeerId(), getNodeBlockPos(p_above), false);
1544                         }
1545
1546                         /* Cheat prevention */
1547                         bool is_valid_dig = true;
1548                         if (!isSingleplayer() && !g_settings->getBool("disable_anticheat")) {
1549                                 v3s16 nocheat_p = playersao->getNoCheatDigPos();
1550                                 float nocheat_t = playersao->getNoCheatDigTime();
1551                                 playersao->noCheatDigEnd();
1552                                 // If player didn't start digging this, ignore dig
1553                                 if (nocheat_p != p_under) {
1554                                         infostream << "Server: NoCheat: " << player->getName()
1555                                                         << " started digging "
1556                                                         << PP(nocheat_p) << " and completed digging "
1557                                                         << PP(p_under) << "; not digging." << std::endl;
1558                                         is_valid_dig = false;
1559                                         // Call callbacks
1560                                         m_script->on_cheat(playersao, "finished_unknown_dig");
1561                                 }
1562                                 // Get player's wielded item
1563                                 ItemStack playeritem;
1564                                 InventoryList *mlist = playersao->getInventory()->getList("main");
1565                                 if (mlist != NULL)
1566                                         playeritem = mlist->getItem(playersao->getWieldIndex());
1567                                 ToolCapabilities playeritem_toolcap =
1568                                                 playeritem.getToolCapabilities(m_itemdef);
1569                                 // Get diggability and expected digging time
1570                                 DigParams params = getDigParams(m_nodedef->get(n).groups,
1571                                                 &playeritem_toolcap);
1572                                 // If can't dig, try hand
1573                                 if (!params.diggable) {
1574                                         const ItemDefinition &hand = m_itemdef->get("");
1575                                         const ToolCapabilities *tp = hand.tool_capabilities;
1576                                         if (tp)
1577                                                 params = getDigParams(m_nodedef->get(n).groups, tp);
1578                                 }
1579                                 // If can't dig, ignore dig
1580                                 if (!params.diggable) {
1581                                         infostream << "Server: NoCheat: " << player->getName()
1582                                                         << " completed digging " << PP(p_under)
1583                                                         << ", which is not diggable with tool. not digging."
1584                                                         << std::endl;
1585                                         is_valid_dig = false;
1586                                         // Call callbacks
1587                                         m_script->on_cheat(playersao, "dug_unbreakable");
1588                                 }
1589                                 // Check digging time
1590                                 // If already invalidated, we don't have to
1591                                 if (!is_valid_dig) {
1592                                         // Well not our problem then
1593                                 }
1594                                 // Clean and long dig
1595                                 else if (params.time > 2.0 && nocheat_t * 1.2 > params.time) {
1596                                         // All is good, but grab time from pool; don't care if
1597                                         // it's actually available
1598                                         playersao->getDigPool().grab(params.time);
1599                                 }
1600                                 // Short or laggy dig
1601                                 // Try getting the time from pool
1602                                 else if (playersao->getDigPool().grab(params.time)) {
1603                                         // All is good
1604                                 }
1605                                 // Dig not possible
1606                                 else {
1607                                         infostream << "Server: NoCheat: " << player->getName()
1608                                                         << " completed digging " << PP(p_under)
1609                                                         << "too fast; not digging." << std::endl;
1610                                         is_valid_dig = false;
1611                                         // Call callbacks
1612                                         m_script->on_cheat(playersao, "dug_too_fast");
1613                                 }
1614                         }
1615
1616                         /* Actually dig node */
1617
1618                         if (is_valid_dig && n.getContent() != CONTENT_IGNORE)
1619                                 m_script->node_on_dig(p_under, n, playersao);
1620
1621                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1622                         RemoteClient *client = getClient(pkt->getPeerId());
1623                         // Send unusual result (that is, node not being removed)
1624                         if (m_env->getMap().getNodeNoEx(p_under).getContent() != CONTENT_AIR) {
1625                                 // Re-send block to revert change on client-side
1626                                 client->SetBlockNotSent(blockpos);
1627                         }
1628                         else {
1629                                 client->ResendBlockIfOnWire(blockpos);
1630                         }
1631                 }
1632         } // action == 2
1633
1634         /*
1635                 3: place block or right-click object
1636         */
1637         else if (action == 3) {
1638                 ItemStack item = playersao->getWieldedItem();
1639
1640                 // Reset build time counter
1641                 if (pointed.type == POINTEDTHING_NODE &&
1642                                 item.getDefinition(m_itemdef).type == ITEM_NODE)
1643                         getClient(pkt->getPeerId())->m_time_from_building = 0.0;
1644
1645                 if (pointed.type == POINTEDTHING_OBJECT) {
1646                         // Right click object
1647
1648                         // Skip if object has been removed
1649                         if (pointed_object->m_removed)
1650                                 return;
1651
1652                         actionstream << player->getName() << " right-clicks object "
1653                                         << pointed.object_id << ": "
1654                                         << pointed_object->getDescription() << std::endl;
1655
1656                         // Do stuff
1657                         pointed_object->rightClick(playersao);
1658                 }
1659                 else if (m_script->item_OnPlace(
1660                                 item, playersao, pointed)) {
1661                         // Placement was handled in lua
1662
1663                         // Apply returned ItemStack
1664                         if (playersao->setWieldedItem(item)) {
1665                                 SendInventory(playersao);
1666                         }
1667                 }
1668
1669                 // If item has node placement prediction, always send the
1670                 // blocks to make sure the client knows what exactly happened
1671                 RemoteClient *client = getClient(pkt->getPeerId());
1672                 v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_above, BS));
1673                 v3s16 blockpos2 = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1674                 if (item.getDefinition(m_itemdef).node_placement_prediction != "") {
1675                         client->SetBlockNotSent(blockpos);
1676                         if (blockpos2 != blockpos) {
1677                                 client->SetBlockNotSent(blockpos2);
1678                         }
1679                 }
1680                 else {
1681                         client->ResendBlockIfOnWire(blockpos);
1682                         if (blockpos2 != blockpos) {
1683                                 client->ResendBlockIfOnWire(blockpos2);
1684                         }
1685                 }
1686         } // action == 3
1687
1688         /*
1689                 4: use
1690         */
1691         else if (action == 4) {
1692                 ItemStack item = playersao->getWieldedItem();
1693
1694                 actionstream << player->getName() << " uses " << item.name
1695                                 << ", pointing at " << pointed.dump() << std::endl;
1696
1697                 if (m_script->item_OnUse(
1698                                 item, playersao, pointed)) {
1699                         // Apply returned ItemStack
1700                         if (playersao->setWieldedItem(item)) {
1701                                 SendInventory(playersao);
1702                         }
1703                 }
1704
1705         } // action == 4
1706
1707
1708         /*
1709                 Catch invalid actions
1710         */
1711         else {
1712                 infostream << "WARNING: Server: Invalid action "
1713                                 << action << std::endl;
1714         }
1715 }
1716
1717 void Server::handleCommand_RemovedSounds(NetworkPacket* pkt)
1718 {
1719         u16 num;
1720         *pkt >> num;
1721         for (u16 k = 0; k < num; k++) {
1722                 s32 id;
1723
1724                 *pkt >> id;
1725
1726                 std::map<s32, ServerPlayingSound>::iterator i =
1727                         m_playing_sounds.find(id);
1728
1729                 if (i == m_playing_sounds.end())
1730                         continue;
1731
1732                 ServerPlayingSound &psound = i->second;
1733                 psound.clients.erase(pkt->getPeerId());
1734                 if (psound.clients.empty())
1735                         m_playing_sounds.erase(i++);
1736         }
1737 }
1738
1739 void Server::handleCommand_NodeMetaFields(NetworkPacket* pkt)
1740 {
1741         v3s16 p;
1742         std::string formname;
1743         u16 num;
1744
1745         *pkt >> p >> formname >> num;
1746
1747         StringMap fields;
1748         for (u16 k = 0; k < num; k++) {
1749                 std::string fieldname;
1750                 *pkt >> fieldname;
1751                 fields[fieldname] = pkt->readLongString();
1752         }
1753
1754         Player *player = m_env->getPlayer(pkt->getPeerId());
1755         if (player == NULL) {
1756                 errorstream << "Server::ProcessData(): Canceling: "
1757                                 "No player for peer_id=" << pkt->getPeerId()
1758                                 << " disconnecting peer!" << std::endl;
1759                 m_con.DisconnectPeer(pkt->getPeerId());
1760                 return;
1761         }
1762
1763         PlayerSAO *playersao = player->getPlayerSAO();
1764         if (playersao == NULL) {
1765                 errorstream << "Server::ProcessData(): Canceling: "
1766                                 "No player object for peer_id=" << pkt->getPeerId()
1767                                 << " disconnecting peer!"  << std::endl;
1768                 m_con.DisconnectPeer(pkt->getPeerId());
1769                 return;
1770         }
1771
1772         // If something goes wrong, this player is to blame
1773         RollbackScopeActor rollback_scope(m_rollback,
1774                         std::string("player:")+player->getName());
1775
1776         // Check the target node for rollback data; leave others unnoticed
1777         RollbackNode rn_old(&m_env->getMap(), p, this);
1778
1779         m_script->node_on_receive_fields(p, formname, fields, playersao);
1780
1781         // Report rollback data
1782         RollbackNode rn_new(&m_env->getMap(), p, this);
1783         if (rollback() && rn_new != rn_old) {
1784                 RollbackAction action;
1785                 action.setSetNode(p, rn_old, rn_new);
1786                 rollback()->reportAction(action);
1787         }
1788 }
1789
1790 void Server::handleCommand_InventoryFields(NetworkPacket* pkt)
1791 {
1792         std::string formname;
1793         u16 num;
1794
1795         *pkt >> formname >> num;
1796
1797         StringMap fields;
1798         for (u16 k = 0; k < num; k++) {
1799                 std::string fieldname;
1800                 *pkt >> fieldname;
1801                 fields[fieldname] = pkt->readLongString();
1802         }
1803
1804         Player *player = m_env->getPlayer(pkt->getPeerId());
1805         if (player == NULL) {
1806                 errorstream << "Server::ProcessData(): Canceling: "
1807                                 "No player for peer_id=" << pkt->getPeerId()
1808                                 << " disconnecting peer!" << std::endl;
1809                 m_con.DisconnectPeer(pkt->getPeerId());
1810                 return;
1811         }
1812
1813         PlayerSAO *playersao = player->getPlayerSAO();
1814         if (playersao == NULL) {
1815                 errorstream << "Server::ProcessData(): Canceling: "
1816                                 "No player object for peer_id=" << pkt->getPeerId()
1817                                 << " disconnecting peer!" << std::endl;
1818                 m_con.DisconnectPeer(pkt->getPeerId());
1819                 return;
1820         }
1821
1822         m_script->on_playerReceiveFields(playersao, formname, fields);
1823 }
1824
1825 void Server::handleCommand_FirstSrp(NetworkPacket* pkt)
1826 {
1827         RemoteClient* client = getClient(pkt->getPeerId(), CS_Invalid);
1828         ClientState cstate = client->getState();
1829
1830         std::string playername = client->getName();
1831
1832         std::string salt;
1833         std::string verification_key;
1834
1835         std::string addr_s = getPeerAddress(pkt->getPeerId()).serializeString();
1836         u8 is_empty;
1837
1838         *pkt >> salt >> verification_key >> is_empty;
1839
1840         verbosestream << "Server: Got TOSERVER_FIRST_SRP from " << addr_s
1841                 << ", with is_empty= " << is_empty << std::endl;
1842
1843         // Either this packet is sent because the user is new or to change the password
1844         if (cstate == CS_HelloSent) {
1845                 if (!client->isMechAllowed(AUTH_MECHANISM_FIRST_SRP)) {
1846                         actionstream << "Server: Client from " << addr_s
1847                                         << " tried to set password without being "
1848                                         << "authenticated, or the username being new." << std::endl;
1849                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1850                         return;
1851                 }
1852
1853                 if (!isSingleplayer() &&
1854                                 g_settings->getBool("disallow_empty_password") &&
1855                                 is_empty == 1) {
1856                         actionstream << "Server: " << playername
1857                                         << " supplied empty password from " << addr_s << std::endl;
1858                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_EMPTY_PASSWORD);
1859                         return;
1860                 }
1861
1862                 std::string initial_ver_key;
1863                 std::string raw_default_password = g_settings->get("default_password");
1864                 // If default_password is empty, allow any initial password
1865                 if (raw_default_password.length() == 0) {
1866                         initial_ver_key = encodeSRPVerifier(verification_key, salt);
1867                 } else {
1868                         initial_ver_key = getSRPVerifier(playername, raw_default_password);
1869                 }
1870
1871                 m_script->createAuth(playername, initial_ver_key);
1872
1873                 acceptAuth(pkt->getPeerId(), false);
1874         } else {
1875                 if (cstate < CS_SudoMode) {
1876                         infostream << "Server::ProcessData(): Ignoring TOSERVER_FIRST_SRP from "
1877                                         << addr_s << ": " << "Client has wrong state " << cstate << "."
1878                                         << std::endl;
1879                         return;
1880                 }
1881                 m_clients.event(pkt->getPeerId(), CSE_SudoLeave);
1882                 std::string pw_db_field = encodeSRPVerifier(verification_key, salt);
1883                 bool success = m_script->setPassword(playername, pw_db_field);
1884                 if (success) {
1885                         actionstream << playername << " changes password" << std::endl;
1886                         SendChatMessage(pkt->getPeerId(), L"Password change successful.");
1887                 } else {
1888                         actionstream << playername << " tries to change password but "
1889                                 << "it fails" << std::endl;
1890                         SendChatMessage(pkt->getPeerId(), L"Password change failed or unavailable.");
1891                 }
1892         }
1893 }
1894
1895 void Server::handleCommand_SrpBytesA(NetworkPacket* pkt)
1896 {
1897         RemoteClient* client = getClient(pkt->getPeerId(), CS_Invalid);
1898         ClientState cstate = client->getState();
1899
1900         bool wantSudo = (cstate == CS_Active);
1901
1902         if (!((cstate == CS_HelloSent) || (cstate == CS_Active))) {
1903                 actionstream << "Server: got SRP _A packet in wrong state "
1904                         << cstate << " from "
1905                         << getPeerAddress(pkt->getPeerId()).serializeString()
1906                         << ". Ignoring." << std::endl;
1907                 return;
1908         }
1909
1910         if (client->chosen_mech != AUTH_MECHANISM_NONE) {
1911                 actionstream << "Server: got SRP _A packet, while auth"
1912                         << "is already going on with mech " << client->chosen_mech
1913                         << " from " << getPeerAddress(pkt->getPeerId()).serializeString()
1914                         << " (wantSudo=" << wantSudo << "). Ignoring." << std::endl;
1915                 if (wantSudo) {
1916                         DenySudoAccess(pkt->getPeerId());
1917                         return;
1918                 } else {
1919                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1920                         return;
1921                 }
1922         }
1923
1924         std::string bytes_A;
1925         u8 based_on;
1926         *pkt >> bytes_A >> based_on;
1927
1928         infostream << "Server: TOSERVER_SRP_BYTES_A received with "
1929                 << "based_on=" << int(based_on) << " and len_A="
1930                 << bytes_A.length() << "." << std::endl;
1931
1932         AuthMechanism chosen = (based_on == 0) ?
1933                 AUTH_MECHANISM_LEGACY_PASSWORD : AUTH_MECHANISM_SRP;
1934
1935         if (wantSudo) {
1936                 if (!client->isSudoMechAllowed(chosen)) {
1937                         actionstream << "Server: Player \"" << client->getName()
1938                                 << "\" at " << getPeerAddress(pkt->getPeerId()).serializeString()
1939                                 << " tried to change password using unallowed mech "
1940                                 << chosen << "." << std::endl;
1941                         DenySudoAccess(pkt->getPeerId());
1942                         return;
1943                 }
1944         } else {
1945                 if (!client->isMechAllowed(chosen)) {
1946                         actionstream << "Server: Client tried to authenticate from "
1947                                 << getPeerAddress(pkt->getPeerId()).serializeString()
1948                                 << " using unallowed mech " << chosen << "." << std::endl;
1949                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1950                         return;
1951                 }
1952         }
1953
1954         client->chosen_mech = chosen;
1955
1956         std::string bytes_s;
1957         std::string bytes_v;
1958
1959         if (based_on == 0) {
1960                 char *p_bytes_s = 0;
1961                 size_t len_s = 0;
1962                 char *p_bytes_v = 0;
1963                 size_t len_v = 0;
1964                 getSRPVerifier(client->getName(), client->enc_pwd,
1965                         &p_bytes_s, &len_s,
1966                         &p_bytes_v, &len_v);
1967                 bytes_s = std::string(p_bytes_s, len_s);
1968                 bytes_v = std::string(p_bytes_v, len_v);
1969                 free(p_bytes_s);
1970                 free(p_bytes_v);
1971         } else if (!decodeSRPVerifier(client->enc_pwd, &bytes_s, &bytes_v)) {
1972                 // Non-base64 errors should have been catched in the init handler
1973                 actionstream << "Server: User " << client->getName()
1974                         << " tried to log in, but srp verifier field"
1975                         << " was invalid (most likely invalid base64)." << std::endl;
1976                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_SERVER_FAIL);
1977                 return;
1978         }
1979
1980         char *bytes_B = 0;
1981         size_t len_B = 0;
1982
1983         client->auth_data = srp_verifier_new(SRP_SHA256, SRP_NG_2048,
1984                 client->getName().c_str(),
1985                 (const unsigned char *) bytes_s.c_str(), bytes_s.size(),
1986                 (const unsigned char *) bytes_v.c_str(), bytes_v.size(),
1987                 (const unsigned char *) bytes_A.c_str(), bytes_A.size(),
1988                 NULL, 0,
1989                 (unsigned char **) &bytes_B, &len_B, NULL, NULL);
1990
1991         if (!bytes_B) {
1992                 actionstream << "Server: User " << client->getName()
1993                         << " tried to log in, SRP-6a safety check violated in _A handler."
1994                         << std::endl;
1995                 if (wantSudo) {
1996                         DenySudoAccess(pkt->getPeerId());
1997                         return;
1998                 } else {
1999                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
2000                         return;
2001                 }
2002         }
2003
2004         NetworkPacket resp_pkt(TOCLIENT_SRP_BYTES_S_B, 0, pkt->getPeerId());
2005         resp_pkt << bytes_s << std::string(bytes_B, len_B);
2006         Send(&resp_pkt);
2007 }
2008
2009 void Server::handleCommand_SrpBytesM(NetworkPacket* pkt)
2010 {
2011         RemoteClient* client = getClient(pkt->getPeerId(), CS_Invalid);
2012         ClientState cstate = client->getState();
2013
2014         bool wantSudo = (cstate == CS_Active);
2015
2016         verbosestream << "Server: Recieved TOCLIENT_SRP_BYTES_M." << std::endl;
2017
2018         if (!((cstate == CS_HelloSent) || (cstate == CS_Active))) {
2019                 actionstream << "Server: got SRP _M packet in wrong state "
2020                         << cstate << " from "
2021                         << getPeerAddress(pkt->getPeerId()).serializeString()
2022                         << ". Ignoring." << std::endl;
2023                 return;
2024         }
2025
2026         if ((client->chosen_mech != AUTH_MECHANISM_SRP)
2027                 && (client->chosen_mech != AUTH_MECHANISM_LEGACY_PASSWORD)) {
2028                 actionstream << "Server: got SRP _M packet, while auth"
2029                         << "is going on with mech " << client->chosen_mech
2030                         << " from " << getPeerAddress(pkt->getPeerId()).serializeString()
2031                         << " (wantSudo=" << wantSudo << "). Denying." << std::endl;
2032                 if (wantSudo) {
2033                         DenySudoAccess(pkt->getPeerId());
2034                         return;
2035                 } else {
2036                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
2037                         return;
2038                 }
2039         }
2040
2041         std::string bytes_M;
2042         *pkt >> bytes_M;
2043
2044         if (srp_verifier_get_session_key_length((SRPVerifier *) client->auth_data)
2045                         != bytes_M.size()) {
2046                 actionstream << "Server: User " << client->getName()
2047                         << " at " << getPeerAddress(pkt->getPeerId()).serializeString()
2048                         << " sent bytes_M with invalid length " << bytes_M.size() << std::endl;
2049                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
2050                 return;
2051         }
2052
2053         unsigned char *bytes_HAMK = 0;
2054
2055         srp_verifier_verify_session((SRPVerifier *) client->auth_data,
2056                 (unsigned char *)bytes_M.c_str(), &bytes_HAMK);
2057
2058         if (!bytes_HAMK) {
2059                 if (wantSudo) {
2060                         actionstream << "Server: User " << client->getName()
2061                                 << " at " << getPeerAddress(pkt->getPeerId()).serializeString()
2062                                 << " tried to change their password, but supplied wrong"
2063                                 << " (SRP) password for authentication." << std::endl;
2064                         DenySudoAccess(pkt->getPeerId());
2065                         return;
2066                 } else {
2067                         actionstream << "Server: User " << client->getName()
2068                                 << " at " << getPeerAddress(pkt->getPeerId()).serializeString()
2069                                 << " supplied wrong (SRP) password from address "
2070                                 << getPeerAddress(pkt->getPeerId()).serializeString()
2071                                 << "." << std::endl;
2072                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_PASSWORD);
2073                         return;
2074                 }
2075         }
2076
2077         acceptAuth(pkt->getPeerId(), wantSudo);
2078 }