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_READ)
 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 = get_encoded_srp_verifier(playerName, default_password);
 265                         auth_mechs |= AUTH_MECHANISM_SRP;
 266                         // Allocate player in db, but only on successful login.
 267                         client->create_player_on_auth_success = true;
 268                 }
 269         }
 270
 271         /*
 272                 Answer with a TOCLIENT_HELLO
 273         */
 274
 275         verbosestream << "Sending TOCLIENT_HELLO with auth method field: "
 276                 << auth_mechs << std::endl;
 277
 278         NetworkPacket resp_pkt(TOCLIENT_HELLO, 1 + 4
 279                 + legacyPlayerNameCasing.size(), pkt->getPeerId());
 280
 281         u16 depl_compress_mode = NETPROTO_COMPRESSION_NONE;
 282         resp_pkt << depl_serial_v << depl_compress_mode << net_proto_version
 283                 << auth_mechs << legacyPlayerNameCasing;
 284
 285         Send(&resp_pkt);
 286
 287         client->allowed_auth_mechs = auth_mechs;
 288         client->setDeployedCompressionMode(depl_compress_mode);
 289
 290         m_clients.event(pkt->getPeerId(), CSE_Hello);
 291 }
 292
 293 void Server::handleCommand_Init_Legacy(NetworkPacket* pkt)
 294 {
 295         // [0] u8 SER_FMT_VER_HIGHEST_READ
 296         // [1] u8[20] player_name
 297         // [21] u8[28] password <--- can be sent without this, from old versions
 298
 299         if (pkt->getSize() < 1+PLAYERNAME_SIZE)
 300                 return;
 301
 302         RemoteClient* client = getClient(pkt->getPeerId(), CS_Created);
 303
 304         std::string addr_s;
 305         try {
 306                 Address address = getPeerAddress(pkt->getPeerId());
 307                 addr_s = address.serializeString();
 308         }
 309         catch (con::PeerNotFoundException &e) {
 310                 /*
 311                  * no peer for this packet found
 312                  * most common reason is peer timeout, e.g. peer didn't
 313                  * respond for some time, your server was overloaded or
 314                  * things like that.
 315                  */
 316                 infostream << "Server::ProcessData(): Canceling: peer "
 317                                 << pkt->getPeerId() << " not found" << std::endl;
 318                 return;
 319         }
 320
 321         // If net_proto_version is set, this client has already been handled
 322         if (client->getState() > CS_Created) {
 323                 verbosestream << "Server: Ignoring multiple TOSERVER_INITs from "
 324                                 << addr_s << " (peer_id=" << pkt->getPeerId() << ")" << std::endl;
 325                 return;
 326         }
 327
 328         verbosestream << "Server: Got TOSERVER_INIT_LEGACY from " << addr_s << " (peer_id="
 329                         << pkt->getPeerId() << ")" << std::endl;
 330
 331         // Do not allow multiple players in simple singleplayer mode.
 332         // This isn't a perfect way to do it, but will suffice for now
 333         if (m_simple_singleplayer_mode && m_clients.getClientIDs().size() > 1) {
 334                 infostream << "Server: Not allowing another client (" << addr_s
 335                                 << ") to connect in simple singleplayer mode" << std::endl;
 336                 DenyAccess_Legacy(pkt->getPeerId(), L"Running in simple singleplayer mode.");
 337                 return;
 338         }
 339
 340         // First byte after command is maximum supported
 341         // serialization version
 342         u8 client_max;
 343
 344         *pkt >> client_max;
 345
 346         u8 our_max = SER_FMT_VER_HIGHEST_READ;
 347         // Use the highest version supported by both
 348         int deployed = std::min(client_max, our_max);
 349         // If it's lower than the lowest supported, give up.
 350         if (deployed < SER_FMT_VER_LOWEST_READ)
 351                 deployed = SER_FMT_VER_INVALID;
 352
 353         if (deployed == SER_FMT_VER_INVALID) {
 354                 actionstream << "Server: A mismatched client tried to connect from "
 355                                 << addr_s << std::endl;
 356                 infostream<<"Server: Cannot negotiate serialization version with "
 357                                 << addr_s << std::endl;
 358                 DenyAccess_Legacy(pkt->getPeerId(), std::wstring(
 359                                 L"Your client's version is not supported.\n"
 360                                 L"Server version is ")
 361                                 + utf8_to_wide(g_version_string) + L"."
 362                 );
 363                 return;
 364         }
 365
 366         client->setPendingSerializationVersion(deployed);
 367
 368         /*
 369                 Read and check network protocol version
 370         */
 371
 372         u16 min_net_proto_version = 0;
 373         if (pkt->getSize() >= 1 + PLAYERNAME_SIZE + PASSWORD_SIZE + 2)
 374                 min_net_proto_version = pkt->getU16(1 + PLAYERNAME_SIZE + PASSWORD_SIZE);
 375
 376         // Use same version as minimum and maximum if maximum version field
 377         // doesn't exist (backwards compatibility)
 378         u16 max_net_proto_version = min_net_proto_version;
 379         if (pkt->getSize() >= 1 + PLAYERNAME_SIZE + PASSWORD_SIZE + 2 + 2)
 380                 max_net_proto_version = pkt->getU16(1 + PLAYERNAME_SIZE + PASSWORD_SIZE + 2);
 381
 382         // Start with client's maximum version
 383         u16 net_proto_version = max_net_proto_version;
 384
 385         // Figure out a working version if it is possible at all
 386         if (max_net_proto_version >= SERVER_PROTOCOL_VERSION_MIN ||
 387                         min_net_proto_version <= SERVER_PROTOCOL_VERSION_MAX) {
 388                 // If maximum is larger than our maximum, go with our maximum
 389                 if (max_net_proto_version > SERVER_PROTOCOL_VERSION_MAX)
 390                         net_proto_version = SERVER_PROTOCOL_VERSION_MAX;
 391                 // Else go with client's maximum
 392                 else
 393                         net_proto_version = max_net_proto_version;
 394         }
 395
 396         // The client will send up to date init packet, ignore this one
 397         if (net_proto_version >= 25)
 398                 return;
 399
 400         verbosestream << "Server: " << addr_s << ": Protocol version: min: "
 401                         << min_net_proto_version << ", max: " << max_net_proto_version
 402                         << ", chosen: " << net_proto_version << std::endl;
 403
 404         client->net_proto_version = net_proto_version;
 405
 406         if (net_proto_version < SERVER_PROTOCOL_VERSION_MIN ||
 407                         net_proto_version > SERVER_PROTOCOL_VERSION_MAX) {
 408                 actionstream << "Server: A mismatched client tried to connect from "
 409                                 << addr_s << std::endl;
 410                 DenyAccess_Legacy(pkt->getPeerId(), std::wstring(
 411                                 L"Your client's version is not supported.\n"
 412                                 L"Server version is ")
 413                                 + utf8_to_wide(g_version_string) + L",\n"
 414                                 + L"server's PROTOCOL_VERSION is "
 415                                 + utf8_to_wide(itos(SERVER_PROTOCOL_VERSION_MIN))
 416                                 + L"..."
 417                                 + utf8_to_wide(itos(SERVER_PROTOCOL_VERSION_MAX))
 418                                 + L", client's PROTOCOL_VERSION is "
 419                                 + utf8_to_wide(itos(min_net_proto_version))
 420                                 + L"..."
 421                                 + utf8_to_wide(itos(max_net_proto_version))
 422                 );
 423                 return;
 424         }
 425
 426         if (g_settings->getBool("strict_protocol_version_checking")) {
 427                 if (net_proto_version != LATEST_PROTOCOL_VERSION) {
 428                         actionstream << "Server: A mismatched (strict) client tried to "
 429                                         << "connect from " << addr_s << std::endl;
 430                         DenyAccess_Legacy(pkt->getPeerId(), std::wstring(
 431                                         L"Your client's version is not supported.\n"
 432                                         L"Server version is ")
 433                                         + utf8_to_wide(g_version_string) + L",\n"
 434                                         + L"server's PROTOCOL_VERSION (strict) is "
 435                                         + utf8_to_wide(itos(LATEST_PROTOCOL_VERSION))
 436                                         + L", client's PROTOCOL_VERSION is "
 437                                         + utf8_to_wide(itos(min_net_proto_version))
 438                                         + L"..."
 439                                         + utf8_to_wide(itos(max_net_proto_version))
 440                         );
 441                         return;
 442                 }
 443         }
 444
 445         /*
 446                 Set up player
 447         */
 448         char playername[PLAYERNAME_SIZE];
 449         unsigned int playername_length = 0;
 450         for (; playername_length < PLAYERNAME_SIZE; playername_length++ ) {
 451                 playername[playername_length] = pkt->getChar(1+playername_length);
 452                 if (pkt->getChar(1+playername_length) == 0)
 453                         break;
 454         }
 455
 456         if (playername_length == PLAYERNAME_SIZE) {
 457                 actionstream << "Server: Player with name exceeding max length "
 458                                 << "tried to connect from " << addr_s << std::endl;
 459                 DenyAccess_Legacy(pkt->getPeerId(), L"Name too long");
 460                 return;
 461         }
 462
 463
 464         if (playername[0]=='\0') {
 465                 actionstream << "Server: Player with an empty name "
 466                                 << "tried to connect from " << addr_s << std::endl;
 467                 DenyAccess_Legacy(pkt->getPeerId(), L"Empty name");
 468                 return;
 469         }
 470
 471         if (string_allowed(playername, PLAYERNAME_ALLOWED_CHARS) == false) {
 472                 actionstream << "Server: Player with an invalid name "
 473                                 << "tried to connect from " << addr_s << std::endl;
 474                 DenyAccess_Legacy(pkt->getPeerId(), L"Name contains unallowed characters");
 475                 return;
 476         }
 477
 478         if (!isSingleplayer() && strcasecmp(playername, "singleplayer") == 0) {
 479                 actionstream << "Server: Player with the name \"singleplayer\" "
 480                                 << "tried to connect from " << addr_s << std::endl;
 481                 DenyAccess_Legacy(pkt->getPeerId(), L"Name is not allowed");
 482                 return;
 483         }
 484
 485         {
 486                 std::string reason;
 487                 if (m_script->on_prejoinplayer(playername, addr_s, &reason)) {
 488                         actionstream << "Server: Player with the name \"" << playername << "\" "
 489                                         << "tried to connect from " << addr_s << " "
 490                                         << "but it was disallowed for the following reason: "
 491                                         << reason << std::endl;
 492                         DenyAccess_Legacy(pkt->getPeerId(), utf8_to_wide(reason.c_str()));
 493                         return;
 494                 }
 495         }
 496
 497         infostream<<"Server: New connection: \""<<playername<<"\" from "
 498                         <<addr_s<<" (peer_id="<<pkt->getPeerId()<<")"<<std::endl;
 499
 500         // Get password
 501         char given_password[PASSWORD_SIZE];
 502         if (pkt->getSize() < 1 + PLAYERNAME_SIZE + PASSWORD_SIZE) {
 503                 // old version - assume blank password
 504                 given_password[0] = 0;
 505         }
 506         else {
 507                 for (u16 i = 0; i < PASSWORD_SIZE - 1; i++) {
 508                         given_password[i] = pkt->getChar(21 + i);
 509                 }
 510                 given_password[PASSWORD_SIZE - 1] = 0;
 511         }
 512
 513         if (!base64_is_valid(given_password)) {
 514                 actionstream << "Server: " << playername
 515                                 << " supplied invalid password hash" << std::endl;
 516                 DenyAccess_Legacy(pkt->getPeerId(), L"Invalid password hash");
 517                 return;
 518         }
 519
 520         // Enforce user limit.
 521         // Don't enforce for users that have some admin right
 522         if (m_clients.getClientIDs(CS_Created).size() >= g_settings->getU16("max_users") &&
 523                         !checkPriv(playername, "server") &&
 524                         !checkPriv(playername, "ban") &&
 525                         !checkPriv(playername, "privs") &&
 526                         !checkPriv(playername, "password") &&
 527                         playername != g_settings->get("name")) {
 528                 actionstream << "Server: " << playername << " tried to join, but there"
 529                                 << " are already max_users="
 530                                 << g_settings->getU16("max_users") << " players." << std::endl;
 531                 DenyAccess_Legacy(pkt->getPeerId(), L"Too many users.");
 532                 return;
 533         }
 534
 535         std::string checkpwd; // Password hash to check against
 536         bool has_auth = m_script->getAuth(playername, &checkpwd, NULL);
 537
 538         // If no authentication info exists for user, create it
 539         if (!has_auth) {
 540                 if (!isSingleplayer() &&
 541                                 g_settings->getBool("disallow_empty_password") &&
 542                                 std::string(given_password) == "") {
 543                         actionstream << "Server: " << playername
 544                                         << " supplied empty password" << std::endl;
 545                         DenyAccess_Legacy(pkt->getPeerId(), L"Empty passwords are "
 546                                         L"disallowed. Set a password and try again.");
 547                         return;
 548                 }
 549                 std::string raw_default_password =
 550                         g_settings->get("default_password");
 551                 std::string initial_password =
 552                         translate_password(playername, raw_default_password);
 553
 554                 // If default_password is empty, allow any initial password
 555                 if (raw_default_password.length() == 0)
 556                         initial_password = given_password;
 557
 558                 m_script->createAuth(playername, initial_password);
 559         }
 560
 561         has_auth = m_script->getAuth(playername, &checkpwd, NULL);
 562
 563         if (!has_auth) {
 564                 actionstream << "Server: " << playername << " cannot be authenticated"
 565                                 << " (auth handler does not work?)" << std::endl;
 566                 DenyAccess_Legacy(pkt->getPeerId(), L"Not allowed to login");
 567                 return;
 568         }
 569
 570         if (given_password != checkpwd) {
 571                 actionstream << "Server: User " << playername
 572                         << " at " << addr_s
 573                         << " supplied wrong password (auth mechanism: legacy)."
 574                         << std::endl;
 575                 DenyAccess_Legacy(pkt->getPeerId(), L"Wrong password");
 576                 return;
 577         }
 578
 579         RemotePlayer *player =
 580                         static_cast<RemotePlayer*>(m_env->getPlayer(playername));
 581
 582         if (player && player->peer_id != 0) {
 583                 actionstream << "Server: " << playername << ": Failed to emerge player"
 584                                 << " (player allocated to an another client)" << std::endl;
 585                 DenyAccess_Legacy(pkt->getPeerId(), L"Another client is connected with this "
 586                                 L"name. If your client closed unexpectedly, try again in "
 587                                 L"a minute.");
 588         }
 589
 590         m_clients.setPlayerName(pkt->getPeerId(), playername);
 591
 592         /*
 593                 Answer with a TOCLIENT_INIT
 594         */
 595
 596         NetworkPacket resp_pkt(TOCLIENT_INIT_LEGACY, 1 + 6 + 8 + 4,
 597                         pkt->getPeerId());
 598
 599         resp_pkt << (u8) deployed << (v3s16) floatToInt(v3f(0,0,0), BS)
 600                         << (u64) m_env->getServerMap().getSeed()
 601                         << g_settings->getFloat("dedicated_server_step");
 602
 603         Send(&resp_pkt);
 604         m_clients.event(pkt->getPeerId(), CSE_InitLegacy);
 605 }
 606
 607 void Server::handleCommand_Init2(NetworkPacket* pkt)
 608 {
 609         verbosestream << "Server: Got TOSERVER_INIT2 from "
 610                         << pkt->getPeerId() << std::endl;
 611
 612         m_clients.event(pkt->getPeerId(), CSE_GotInit2);
 613         u16 protocol_version = m_clients.getProtocolVersion(pkt->getPeerId());
 614
 615
 616         ///// begin compatibility code
 617         PlayerSAO* playersao = NULL;
 618         if (protocol_version <= 22) {
 619                 playersao = StageTwoClientInit(pkt->getPeerId());
 620
 621                 if (playersao == NULL) {
 622                         actionstream
 623                                 << "TOSERVER_INIT2 stage 2 client init failed for peer "
 624                                 << pkt->getPeerId() << std::endl;
 625                         return;
 626                 }
 627         }
 628         ///// end compatibility code
 629
 630         /*
 631                 Send some initialization data
 632         */
 633
 634         infostream << "Server: Sending content to "
 635                         << getPlayerName(pkt->getPeerId()) << std::endl;
 636
 637         // Send player movement settings
 638         SendMovement(pkt->getPeerId());
 639
 640         // Send item definitions
 641         SendItemDef(pkt->getPeerId(), m_itemdef, protocol_version);
 642
 643         // Send node definitions
 644         SendNodeDef(pkt->getPeerId(), m_nodedef, protocol_version);
 645
 646         m_clients.event(pkt->getPeerId(), CSE_SetDefinitionsSent);
 647
 648         // Send media announcement
 649         sendMediaAnnouncement(pkt->getPeerId());
 650
 651         // Send detached inventories
 652         sendDetachedInventories(pkt->getPeerId());
 653
 654         // Send time of day
 655         u16 time = m_env->getTimeOfDay();
 656         float time_speed = g_settings->getFloat("time_speed");
 657         SendTimeOfDay(pkt->getPeerId(), time, time_speed);
 658
 659         ///// begin compatibility code
 660         if (protocol_version <= 22) {
 661                 m_clients.event(pkt->getPeerId(), CSE_SetClientReady);
 662                 m_script->on_joinplayer(playersao);
 663         }
 664         ///// end compatibility code
 665
 666         // Warnings about protocol version can be issued here
 667         if (getClient(pkt->getPeerId())->net_proto_version < LATEST_PROTOCOL_VERSION) {
 668                 SendChatMessage(pkt->getPeerId(), L"# Server: WARNING: YOUR CLIENT'S "
 669                                 L"VERSION MAY NOT BE FULLY COMPATIBLE WITH THIS SERVER!");
 670         }
 671 }
 672
 673 void Server::handleCommand_RequestMedia(NetworkPacket* pkt)
 674 {
 675         std::vector<std::string> tosend;
 676         u16 numfiles;
 677
 678         *pkt >> numfiles;
 679
 680         infostream << "Sending " << numfiles << " files to "
 681                         << getPlayerName(pkt->getPeerId()) << std::endl;
 682         verbosestream << "TOSERVER_REQUEST_MEDIA: " << std::endl;
 683
 684         for (u16 i = 0; i < numfiles; i++) {
 685                 std::string name;
 686
 687                 *pkt >> name;
 688
 689                 tosend.push_back(name);
 690                 verbosestream << "TOSERVER_REQUEST_MEDIA: requested file "
 691                                 << name << std::endl;
 692         }
 693
 694         sendRequestedMedia(pkt->getPeerId(), tosend);
 695 }
 696
 697 void Server::handleCommand_ReceivedMedia(NetworkPacket* pkt)
 698 {
 699 }
 700
 701 void Server::handleCommand_ClientReady(NetworkPacket* pkt)
 702 {
 703         u16 peer_id = pkt->getPeerId();
 704         u16 peer_proto_ver = getClient(peer_id, CS_InitDone)->net_proto_version;
 705
 706         // clients <= protocol version 22 did not send ready message,
 707         // they're already initialized
 708         if (peer_proto_ver <= 22) {
 709                 infostream << "Client sent message not expected by a "
 710                         << "client using protocol version <= 22,"
 711                         << "disconnecting peer_id: " << peer_id << std::endl;
 712                 m_con.DisconnectPeer(peer_id);
 713                 return;
 714         }
 715
 716         PlayerSAO* playersao = StageTwoClientInit(peer_id);
 717
 718         if (playersao == NULL) {
 719                 actionstream
 720                         << "TOSERVER_CLIENT_READY stage 2 client init failed for peer_id: "
 721                         << peer_id << std::endl;
 722                 m_con.DisconnectPeer(peer_id);
 723                 return;
 724         }
 725
 726
 727         if (pkt->getSize() < 8) {
 728                 errorstream
 729                         << "TOSERVER_CLIENT_READY client sent inconsistent data, disconnecting peer_id: "
 730                         << peer_id << std::endl;
 731                 m_con.DisconnectPeer(peer_id);
 732                 return;
 733         }
 734
 735         u8 major_ver, minor_ver, patch_ver, reserved;
 736         std::string full_ver;
 737         *pkt >> major_ver >> minor_ver >> patch_ver >> reserved >> full_ver;
 738
 739         m_clients.setClientVersion(
 740                         peer_id, major_ver, minor_ver, patch_ver,
 741                         full_ver);
 742
 743         m_clients.event(peer_id, CSE_SetClientReady);
 744         m_script->on_joinplayer(playersao);
 745 }
 746
 747 void Server::handleCommand_GotBlocks(NetworkPacket* pkt)
 748 {
 749         if (pkt->getSize() < 1)
 750                 return;
 751
 752         /*
 753                 [0] u16 command
 754                 [2] u8 count
 755                 [3] v3s16 pos_0
 756                 [3+6] v3s16 pos_1
 757                 ...
 758         */
 759
 760         u8 count;
 761         *pkt >> count;
 762
 763         RemoteClient *client = getClient(pkt->getPeerId());
 764
 765         if ((s16)pkt->getSize() < 1 + (int)count * 6) {
 766                 throw con::InvalidIncomingDataException
 767                                 ("GOTBLOCKS length is too short");
 768         }
 769
 770         for (u16 i = 0; i < count; i++) {
 771                 v3s16 p;
 772                 *pkt >> p;
 773                 client->GotBlock(p);
 774         }
 775 }
 776
 777 void Server::handleCommand_PlayerPos(NetworkPacket* pkt)
 778 {
 779         if (pkt->getSize() < 12 + 12 + 4 + 4)
 780                 return;
 781
 782         v3s32 ps, ss;
 783         s32 f32pitch, f32yaw;
 784
 785         *pkt >> ps;
 786         *pkt >> ss;
 787         *pkt >> f32pitch;
 788         *pkt >> f32yaw;
 789
 790         f32 pitch = (f32)f32pitch / 100.0;
 791         f32 yaw = (f32)f32yaw / 100.0;
 792         u32 keyPressed = 0;
 793
 794         if (pkt->getSize() >= 12 + 12 + 4 + 4 + 4)
 795                 *pkt >> keyPressed;
 796
 797         v3f position((f32)ps.X / 100.0, (f32)ps.Y / 100.0, (f32)ps.Z / 100.0);
 798         v3f speed((f32)ss.X / 100.0, (f32)ss.Y / 100.0, (f32)ss.Z / 100.0);
 799
 800         pitch = modulo360f(pitch);
 801         yaw = modulo360f(yaw);
 802
 803         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
 804         if (player == NULL) {
 805                 errorstream << "Server::ProcessData(): Canceling: "
 806                                 "No player for peer_id=" << pkt->getPeerId()
 807                                 << " disconnecting peer!" << std::endl;
 808                 m_con.DisconnectPeer(pkt->getPeerId());
 809                 return;
 810         }
 811
 812         PlayerSAO *playersao = player->getPlayerSAO();
 813         if (playersao == NULL) {
 814                 errorstream << "Server::ProcessData(): Canceling: "
 815                                 "No player object for peer_id=" << pkt->getPeerId()
 816                                 << " disconnecting peer!" << std::endl;
 817                 m_con.DisconnectPeer(pkt->getPeerId());
 818                 return;
 819         }
 820
 821         // If player is dead we don't care of this packet
 822         if (playersao->isDead()) {
 823                 verbosestream << "TOSERVER_PLAYERPOS: " << player->getName()
 824                                 << " is dead. Ignoring packet";
 825                 return;
 826         }
 827
 828         playersao->setBasePosition(position);
 829         player->setSpeed(speed);
 830         playersao->setPitch(pitch);
 831         playersao->setYaw(yaw);
 832         player->keyPressed = keyPressed;
 833         player->control.up = (keyPressed & 1);
 834         player->control.down = (keyPressed & 2);
 835         player->control.left = (keyPressed & 4);
 836         player->control.right = (keyPressed & 8);
 837         player->control.jump = (keyPressed & 16);
 838         player->control.aux1 = (keyPressed & 32);
 839         player->control.sneak = (keyPressed & 64);
 840         player->control.LMB = (keyPressed & 128);
 841         player->control.RMB = (keyPressed & 256);
 842
 843         if (playersao->checkMovementCheat()) {
 844                 // Call callbacks
 845                 m_script->on_cheat(playersao, "moved_too_fast");
 846                 SendMovePlayer(pkt->getPeerId());
 847         }
 848 }
 849
 850 void Server::handleCommand_DeletedBlocks(NetworkPacket* pkt)
 851 {
 852         if (pkt->getSize() < 1)
 853                 return;
 854
 855         /*
 856                 [0] u16 command
 857                 [2] u8 count
 858                 [3] v3s16 pos_0
 859                 [3+6] v3s16 pos_1
 860                 ...
 861         */
 862
 863         u8 count;
 864         *pkt >> count;
 865
 866         RemoteClient *client = getClient(pkt->getPeerId());
 867
 868         if ((s16)pkt->getSize() < 1 + (int)count * 6) {
 869                 throw con::InvalidIncomingDataException
 870                                 ("DELETEDBLOCKS length is too short");
 871         }
 872
 873         for (u16 i = 0; i < count; i++) {
 874                 v3s16 p;
 875                 *pkt >> p;
 876                 client->SetBlockNotSent(p);
 877         }
 878 }
 879
 880 void Server::handleCommand_InventoryAction(NetworkPacket* pkt)
 881 {
 882         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
 883
 884         if (player == NULL) {
 885                 errorstream << "Server::ProcessData(): Canceling: "
 886                                 "No player for peer_id=" << pkt->getPeerId()
 887                                 << " disconnecting peer!" << std::endl;
 888                 m_con.DisconnectPeer(pkt->getPeerId());
 889                 return;
 890         }
 891
 892         PlayerSAO *playersao = player->getPlayerSAO();
 893         if (playersao == NULL) {
 894                 errorstream << "Server::ProcessData(): Canceling: "
 895                                 "No player object for peer_id=" << pkt->getPeerId()
 896                                 << " disconnecting peer!" << std::endl;
 897                 m_con.DisconnectPeer(pkt->getPeerId());
 898                 return;
 899         }
 900
 901         // Strip command and create a stream
 902         std::string datastring(pkt->getString(0), pkt->getSize());
 903         verbosestream << "TOSERVER_INVENTORY_ACTION: data=" << datastring
 904                 << std::endl;
 905         std::istringstream is(datastring, std::ios_base::binary);
 906         // Create an action
 907         InventoryAction *a = InventoryAction::deSerialize(is);
 908         if (a == NULL) {
 909                 infostream << "TOSERVER_INVENTORY_ACTION: "
 910                                 << "InventoryAction::deSerialize() returned NULL"
 911                                 << std::endl;
 912                 return;
 913         }
 914
 915         // If something goes wrong, this player is to blame
 916         RollbackScopeActor rollback_scope(m_rollback,
 917                         std::string("player:")+player->getName());
 918
 919         /*
 920                 Note: Always set inventory not sent, to repair cases
 921                 where the client made a bad prediction.
 922         */
 923
 924         /*
 925                 Handle restrictions and special cases of the move action
 926         */
 927         if (a->getType() == IACTION_MOVE) {
 928                 IMoveAction *ma = (IMoveAction*)a;
 929
 930                 ma->from_inv.applyCurrentPlayer(player->getName());
 931                 ma->to_inv.applyCurrentPlayer(player->getName());
 932
 933                 setInventoryModified(ma->from_inv, false);
 934                 setInventoryModified(ma->to_inv, false);
 935
 936                 bool from_inv_is_current_player =
 937                         (ma->from_inv.type == InventoryLocation::PLAYER) &&
 938                         (ma->from_inv.name == player->getName());
 939
 940                 bool to_inv_is_current_player =
 941                         (ma->to_inv.type == InventoryLocation::PLAYER) &&
 942                         (ma->to_inv.name == player->getName());
 943
 944                 /*
 945                         Disable moving items out of craftpreview
 946                 */
 947                 if (ma->from_list == "craftpreview") {
 948                         infostream << "Ignoring IMoveAction from "
 949                                         << (ma->from_inv.dump()) << ":" << ma->from_list
 950                                         << " to " << (ma->to_inv.dump()) << ":" << ma->to_list
 951                                         << " because src is " << ma->from_list << std::endl;
 952                         delete a;
 953                         return;
 954                 }
 955
 956                 /*
 957                         Disable moving items into craftresult and craftpreview
 958                 */
 959                 if (ma->to_list == "craftpreview" || ma->to_list == "craftresult") {
 960                         infostream << "Ignoring IMoveAction from "
 961                                         << (ma->from_inv.dump()) << ":" << ma->from_list
 962                                         << " to " << (ma->to_inv.dump()) << ":" << ma->to_list
 963                                         << " because dst is " << ma->to_list << std::endl;
 964                         delete a;
 965                         return;
 966                 }
 967
 968                 // Disallow moving items in elsewhere than player's inventory
 969                 // if not allowed to interact
 970                 if (!checkPriv(player->getName(), "interact") &&
 971                                 (!from_inv_is_current_player ||
 972                                 !to_inv_is_current_player)) {
 973                         infostream << "Cannot move outside of player's inventory: "
 974                                         << "No interact privilege" << std::endl;
 975                         delete a;
 976                         return;
 977                 }
 978         }
 979         /*
 980                 Handle restrictions and special cases of the drop action
 981         */
 982         else if (a->getType() == IACTION_DROP) {
 983                 IDropAction *da = (IDropAction*)a;
 984
 985                 da->from_inv.applyCurrentPlayer(player->getName());
 986
 987                 setInventoryModified(da->from_inv, false);
 988
 989                 /*
 990                         Disable dropping items out of craftpreview
 991                 */
 992                 if (da->from_list == "craftpreview") {
 993                         infostream << "Ignoring IDropAction from "
 994                                         << (da->from_inv.dump()) << ":" << da->from_list
 995                                         << " because src is " << da->from_list << std::endl;
 996                         delete a;
 997                         return;
 998                 }
 999
1000                 // Disallow dropping items if not allowed to interact
1001                 if (!checkPriv(player->getName(), "interact")) {
1002                         delete a;
1003                         return;
1004                 }
1005         }
1006         /*
1007                 Handle restrictions and special cases of the craft action
1008         */
1009         else if (a->getType() == IACTION_CRAFT) {
1010                 ICraftAction *ca = (ICraftAction*)a;
1011
1012                 ca->craft_inv.applyCurrentPlayer(player->getName());
1013
1014                 setInventoryModified(ca->craft_inv, false);
1015
1016                 //bool craft_inv_is_current_player =
1017                 //      (ca->craft_inv.type == InventoryLocation::PLAYER) &&
1018                 //      (ca->craft_inv.name == player->getName());
1019
1020                 // Disallow crafting if not allowed to interact
1021                 if (!checkPriv(player->getName(), "interact")) {
1022                         infostream << "Cannot craft: "
1023                                         << "No interact privilege" << std::endl;
1024                         delete a;
1025                         return;
1026                 }
1027         }
1028
1029         // Do the action
1030         a->apply(this, playersao, this);
1031         // Eat the action
1032         delete a;
1033
1034         SendInventory(playersao);
1035 }
1036
1037 void Server::handleCommand_ChatMessage(NetworkPacket* pkt)
1038 {
1039         /*
1040                 u16 command
1041                 u16 length
1042                 wstring message
1043         */
1044         u16 len;
1045         *pkt >> len;
1046
1047         std::wstring message;
1048         for (u16 i = 0; i < len; i++) {
1049                 u16 tmp_wchar;
1050                 *pkt >> tmp_wchar;
1051
1052                 message += (wchar_t)tmp_wchar;
1053         }
1054
1055         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
1056         if (player == NULL) {
1057                 errorstream << "Server::ProcessData(): Canceling: "
1058                                 "No player for peer_id=" << pkt->getPeerId()
1059                                 << " disconnecting peer!" << std::endl;
1060                 m_con.DisconnectPeer(pkt->getPeerId());
1061                 return;
1062         }
1063
1064         // Get player name of this client
1065         std::string name = player->getName();
1066         std::wstring wname = narrow_to_wide(name);
1067
1068         std::wstring answer_to_sender = handleChat(name, wname, message,
1069                 true, dynamic_cast<RemotePlayer *>(player));
1070         if (!answer_to_sender.empty()) {
1071                 // Send the answer to sender
1072                 SendChatMessage(pkt->getPeerId(), answer_to_sender);
1073         }
1074 }
1075
1076 void Server::handleCommand_Damage(NetworkPacket* pkt)
1077 {
1078         u8 damage;
1079
1080         *pkt >> damage;
1081
1082         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
1083
1084         if (player == NULL) {
1085                 errorstream << "Server::ProcessData(): Canceling: "
1086                                 "No player for peer_id=" << pkt->getPeerId()
1087                                 << " disconnecting peer!" << std::endl;
1088                 m_con.DisconnectPeer(pkt->getPeerId());
1089                 return;
1090         }
1091
1092         PlayerSAO *playersao = player->getPlayerSAO();
1093         if (playersao == NULL) {
1094                 errorstream << "Server::ProcessData(): Canceling: "
1095                                 "No player object for peer_id=" << pkt->getPeerId()
1096                                 << " disconnecting peer!" << std::endl;
1097                 m_con.DisconnectPeer(pkt->getPeerId());
1098                 return;
1099         }
1100
1101         if (g_settings->getBool("enable_damage")) {
1102                 actionstream << player->getName() << " damaged by "
1103                                 << (int)damage << " hp at " << PP(playersao->getBasePosition() / BS)
1104                                 << std::endl;
1105
1106                 playersao->setHP(playersao->getHP() - damage);
1107                 SendPlayerHPOrDie(playersao);
1108         }
1109 }
1110
1111 void Server::handleCommand_Breath(NetworkPacket* pkt)
1112 {
1113         u16 breath;
1114
1115         *pkt >> breath;
1116
1117         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
1118
1119         if (player == NULL) {
1120                 errorstream << "Server::ProcessData(): Canceling: "
1121                                 "No player for peer_id=" << pkt->getPeerId()
1122                                 << " disconnecting peer!" << std::endl;
1123                 m_con.DisconnectPeer(pkt->getPeerId());
1124                 return;
1125         }
1126
1127
1128         PlayerSAO *playersao = player->getPlayerSAO();
1129         if (playersao == NULL) {
1130                 errorstream << "Server::ProcessData(): Canceling: "
1131                                 "No player object for peer_id=" << pkt->getPeerId()
1132                                 << " disconnecting peer!" << std::endl;
1133                 m_con.DisconnectPeer(pkt->getPeerId());
1134                 return;
1135         }
1136
1137         /*
1138          * If player is dead, we don't need to update the breath
1139          * He is dead !
1140          */
1141         if (playersao->isDead()) {
1142                 verbosestream << "TOSERVER_BREATH: " << player->getName()
1143                                 << " is dead. Ignoring packet";
1144                 return;
1145         }
1146
1147         playersao->setBreath(breath);
1148         SendPlayerBreath(pkt->getPeerId());
1149 }
1150
1151 void Server::handleCommand_Password(NetworkPacket* pkt)
1152 {
1153         if (pkt->getSize() != PASSWORD_SIZE * 2)
1154                 return;
1155
1156         std::string oldpwd;
1157         std::string newpwd;
1158
1159         // Deny for clients using the new protocol
1160         RemoteClient* client = getClient(pkt->getPeerId(), CS_Created);
1161         if (client->net_proto_version >= 25) {
1162                 infostream << "Server::handleCommand_Password(): Denying change: "
1163                         << " Client protocol version for peer_id=" << pkt->getPeerId()
1164                         << " too new!" << std::endl;
1165                 return;
1166         }
1167
1168         for (u16 i = 0; i < PASSWORD_SIZE - 1; i++) {
1169                 char c = pkt->getChar(i);
1170                 if (c == 0)
1171                         break;
1172                 oldpwd += c;
1173         }
1174
1175         for (u16 i = 0; i < PASSWORD_SIZE - 1; i++) {
1176                 char c = pkt->getChar(PASSWORD_SIZE + i);
1177                 if (c == 0)
1178                         break;
1179                 newpwd += c;
1180         }
1181
1182         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
1183         if (player == NULL) {
1184                 errorstream << "Server::ProcessData(): Canceling: "
1185                                 "No player for peer_id=" << pkt->getPeerId()
1186                                 << " disconnecting peer!" << std::endl;
1187                 m_con.DisconnectPeer(pkt->getPeerId());
1188                 return;
1189         }
1190
1191         if (!base64_is_valid(newpwd)) {
1192                 infostream<<"Server: " << player->getName() <<
1193                                 " supplied invalid password hash" << std::endl;
1194                 // Wrong old password supplied!!
1195                 SendChatMessage(pkt->getPeerId(), L"Invalid new password hash supplied. Password NOT changed.");
1196                 return;
1197         }
1198
1199         infostream << "Server: Client requests a password change from "
1200                         << "'" << oldpwd << "' to '" << newpwd << "'" << std::endl;
1201
1202         std::string playername = player->getName();
1203
1204         std::string checkpwd;
1205         m_script->getAuth(playername, &checkpwd, NULL);
1206
1207         if (oldpwd != checkpwd) {
1208                 infostream << "Server: invalid old password" << std::endl;
1209                 // Wrong old password supplied!!
1210                 SendChatMessage(pkt->getPeerId(), L"Invalid old password supplied. Password NOT changed.");
1211                 return;
1212         }
1213
1214         bool success = m_script->setPassword(playername, newpwd);
1215         if (success) {
1216                 actionstream << player->getName() << " changes password" << std::endl;
1217                 SendChatMessage(pkt->getPeerId(), L"Password change successful.");
1218         } else {
1219                 actionstream << player->getName() << " tries to change password but "
1220                                 << "it fails" << std::endl;
1221                 SendChatMessage(pkt->getPeerId(), L"Password change failed or unavailable.");
1222         }
1223 }
1224
1225 void Server::handleCommand_PlayerItem(NetworkPacket* pkt)
1226 {
1227         if (pkt->getSize() < 2)
1228                 return;
1229
1230         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
1231
1232         if (player == NULL) {
1233                 errorstream << "Server::ProcessData(): Canceling: "
1234                                 "No player for peer_id=" << pkt->getPeerId()
1235                                 << " disconnecting peer!" << std::endl;
1236                 m_con.DisconnectPeer(pkt->getPeerId());
1237                 return;
1238         }
1239
1240         PlayerSAO *playersao = player->getPlayerSAO();
1241         if (playersao == NULL) {
1242                 errorstream << "Server::ProcessData(): Canceling: "
1243                                 "No player object for peer_id=" << pkt->getPeerId()
1244                                 << " disconnecting peer!" << std::endl;
1245                 m_con.DisconnectPeer(pkt->getPeerId());
1246                 return;
1247         }
1248
1249         u16 item;
1250
1251         *pkt >> item;
1252
1253         playersao->setWieldIndex(item);
1254 }
1255
1256 void Server::handleCommand_Respawn(NetworkPacket* pkt)
1257 {
1258         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
1259         if (player == NULL) {
1260                 errorstream << "Server::ProcessData(): Canceling: "
1261                                 "No player for peer_id=" << pkt->getPeerId()
1262                                 << " disconnecting peer!" << std::endl;
1263                 m_con.DisconnectPeer(pkt->getPeerId());
1264                 return;
1265         }
1266
1267         PlayerSAO *playersao = player->getPlayerSAO();
1268         assert(playersao);
1269
1270         if (!playersao->isDead())
1271                 return;
1272
1273         RespawnPlayer(pkt->getPeerId());
1274
1275         actionstream << player->getName() << " respawns at "
1276                         << PP(playersao->getBasePosition() / BS) << std::endl;
1277
1278         // ActiveObject is added to environment in AsyncRunStep after
1279         // the previous addition has been successfully removed
1280 }
1281
1282 void Server::handleCommand_Interact(NetworkPacket* pkt)
1283 {
1284         std::string datastring(pkt->getString(0), pkt->getSize());
1285         std::istringstream is(datastring, std::ios_base::binary);
1286
1287         /*
1288                 [0] u16 command
1289                 [2] u8 action
1290                 [3] u16 item
1291                 [5] u32 length of the next item
1292                 [9] serialized PointedThing
1293                 actions:
1294                 0: start digging (from undersurface) or use
1295                 1: stop digging (all parameters ignored)
1296                 2: digging completed
1297                 3: place block or item (to abovesurface)
1298                 4: use item
1299         */
1300         u8 action = readU8(is);
1301         u16 item_i = readU16(is);
1302         std::istringstream tmp_is(deSerializeLongString(is), std::ios::binary);
1303         PointedThing pointed;
1304         pointed.deSerialize(tmp_is);
1305
1306         verbosestream << "TOSERVER_INTERACT: action=" << (int)action << ", item="
1307                         << item_i << ", pointed=" << pointed.dump() << std::endl;
1308
1309         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
1310
1311         if (player == NULL) {
1312                 errorstream << "Server::ProcessData(): Canceling: "
1313                                 "No player for peer_id=" << pkt->getPeerId()
1314                                 << " disconnecting peer!" << std::endl;
1315                 m_con.DisconnectPeer(pkt->getPeerId());
1316                 return;
1317         }
1318
1319         PlayerSAO *playersao = player->getPlayerSAO();
1320         if (playersao == NULL) {
1321                 errorstream << "Server::ProcessData(): Canceling: "
1322                                 "No player object for peer_id=" << pkt->getPeerId()
1323                                 << " disconnecting peer!" << std::endl;
1324                 m_con.DisconnectPeer(pkt->getPeerId());
1325                 return;
1326         }
1327
1328         if (playersao->isDead()) {
1329                 verbosestream << "TOSERVER_INTERACT: " << player->getName()
1330                                 << " is dead. Ignoring packet";
1331                 return;
1332         }
1333
1334         v3f player_pos = playersao->getLastGoodPosition();
1335
1336         // Update wielded item
1337         playersao->setWieldIndex(item_i);
1338
1339         // Get pointed to node (undefined if not POINTEDTYPE_NODE)
1340         v3s16 p_under = pointed.node_undersurface;
1341         v3s16 p_above = pointed.node_abovesurface;
1342
1343         // Get pointed to object (NULL if not POINTEDTYPE_OBJECT)
1344         ServerActiveObject *pointed_object = NULL;
1345         if (pointed.type == POINTEDTHING_OBJECT) {
1346                 pointed_object = m_env->getActiveObject(pointed.object_id);
1347                 if (pointed_object == NULL) {
1348                         verbosestream << "TOSERVER_INTERACT: "
1349                                 "pointed object is NULL" << std::endl;
1350                         return;
1351                 }
1352
1353         }
1354
1355         v3f pointed_pos_under = player_pos;
1356         v3f pointed_pos_above = player_pos;
1357         if (pointed.type == POINTEDTHING_NODE) {
1358                 pointed_pos_under = intToFloat(p_under, BS);
1359                 pointed_pos_above = intToFloat(p_above, BS);
1360         }
1361         else if (pointed.type == POINTEDTHING_OBJECT) {
1362                 pointed_pos_under = pointed_object->getBasePosition();
1363                 pointed_pos_above = pointed_pos_under;
1364         }
1365
1366         /*
1367                 Check that target is reasonably close
1368                 (only when digging or placing things)
1369         */
1370         static const bool enable_anticheat = !g_settings->getBool("disable_anticheat");
1371         if ((action == 0 || action == 2 || action == 3) &&
1372                         (enable_anticheat && !isSingleplayer())) {
1373                 float d = player_pos.getDistanceFrom(pointed_pos_under);
1374                 float max_d = BS * 14; // Just some large enough value
1375                 if (d > max_d) {
1376                         actionstream << "Player " << player->getName()
1377                                         << " tried to access " << pointed.dump()
1378                                         << " from too far: "
1379                                         << "d=" << d <<", max_d=" << max_d
1380                                         << ". ignoring." << std::endl;
1381                         // Re-send block to revert change on client-side
1382                         RemoteClient *client = getClient(pkt->getPeerId());
1383                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1384                         client->SetBlockNotSent(blockpos);
1385                         // Call callbacks
1386                         m_script->on_cheat(playersao, "interacted_too_far");
1387                         // Do nothing else
1388                         return;
1389                 }
1390         }
1391
1392         /*
1393                 Make sure the player is allowed to do it
1394         */
1395         if (!checkPriv(player->getName(), "interact")) {
1396                 actionstream<<player->getName()<<" attempted to interact with "
1397                                 <<pointed.dump()<<" without 'interact' privilege"
1398                                 <<std::endl;
1399                 // Re-send block to revert change on client-side
1400                 RemoteClient *client = getClient(pkt->getPeerId());
1401                 // Digging completed -> under
1402                 if (action == 2) {
1403                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1404                         client->SetBlockNotSent(blockpos);
1405                 }
1406                 // Placement -> above
1407                 if (action == 3) {
1408                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_above, BS));
1409                         client->SetBlockNotSent(blockpos);
1410                 }
1411                 return;
1412         }
1413
1414         /*
1415                 If something goes wrong, this player is to blame
1416         */
1417         RollbackScopeActor rollback_scope(m_rollback,
1418                         std::string("player:")+player->getName());
1419
1420         /*
1421                 0: start digging or punch object
1422         */
1423         if (action == 0) {
1424                 if (pointed.type == POINTEDTHING_NODE) {
1425                         /*
1426                                 NOTE: This can be used in the future to check if
1427                                 somebody is cheating, by checking the timing.
1428                         */
1429
1430                         MapNode n(CONTENT_IGNORE);
1431                         bool pos_ok;
1432
1433                         n = m_env->getMap().getNodeNoEx(p_under, &pos_ok);
1434                         if (!pos_ok) {
1435                                 infostream << "Server: Not punching: Node not found."
1436                                                 << " Adding block to emerge queue."
1437                                                 << std::endl;
1438                                 m_emerge->enqueueBlockEmerge(pkt->getPeerId(),
1439                                         getNodeBlockPos(p_above), false);
1440                         }
1441
1442                         if (n.getContent() != CONTENT_IGNORE)
1443                                 m_script->node_on_punch(p_under, n, playersao, pointed);
1444
1445                         // Cheat prevention
1446                         playersao->noCheatDigStart(p_under);
1447                 }
1448                 else if (pointed.type == POINTEDTHING_OBJECT) {
1449                         // Skip if object has been removed
1450                         if (pointed_object->m_removed)
1451                                 return;
1452
1453                         actionstream<<player->getName()<<" punches object "
1454                                         <<pointed.object_id<<": "
1455                                         <<pointed_object->getDescription()<<std::endl;
1456
1457                         ItemStack punchitem = playersao->getWieldedItem();
1458                         ToolCapabilities toolcap =
1459                                         punchitem.getToolCapabilities(m_itemdef);
1460                         v3f dir = (pointed_object->getBasePosition() -
1461                                         (playersao->getBasePosition() + playersao->getEyeOffset())
1462                                                 ).normalize();
1463                         float time_from_last_punch =
1464                                 playersao->resetTimeFromLastPunch();
1465
1466                         s16 src_original_hp = pointed_object->getHP();
1467                         s16 dst_origin_hp = playersao->getHP();
1468
1469                         pointed_object->punch(dir, &toolcap, playersao,
1470                                         time_from_last_punch);
1471
1472                         // If the object is a player and its HP changed
1473                         if (src_original_hp != pointed_object->getHP() &&
1474                                         pointed_object->getType() == ACTIVEOBJECT_TYPE_PLAYER) {
1475                                 SendPlayerHPOrDie((PlayerSAO *)pointed_object);
1476                         }
1477
1478                         // If the puncher is a player and its HP changed
1479                         if (dst_origin_hp != playersao->getHP())
1480                                 SendPlayerHPOrDie(playersao);
1481                 }
1482
1483         } // action == 0
1484
1485         /*
1486                 1: stop digging
1487         */
1488         else if (action == 1) {
1489         } // action == 1
1490
1491         /*
1492                 2: Digging completed
1493         */
1494         else if (action == 2) {
1495                 // Only digging of nodes
1496                 if (pointed.type == POINTEDTHING_NODE) {
1497                         bool pos_ok;
1498                         MapNode n = m_env->getMap().getNodeNoEx(p_under, &pos_ok);
1499                         if (!pos_ok) {
1500                                 infostream << "Server: Not finishing digging: Node not found."
1501                                                 << " Adding block to emerge queue."
1502                                                 << std::endl;
1503                                 m_emerge->enqueueBlockEmerge(pkt->getPeerId(),
1504                                         getNodeBlockPos(p_above), false);
1505                         }
1506
1507                         /* Cheat prevention */
1508                         bool is_valid_dig = true;
1509                         if (enable_anticheat && !isSingleplayer()) {
1510                                 v3s16 nocheat_p = playersao->getNoCheatDigPos();
1511                                 float nocheat_t = playersao->getNoCheatDigTime();
1512                                 playersao->noCheatDigEnd();
1513                                 // If player didn't start digging this, ignore dig
1514                                 if (nocheat_p != p_under) {
1515                                         infostream << "Server: NoCheat: " << player->getName()
1516                                                         << " started digging "
1517                                                         << PP(nocheat_p) << " and completed digging "
1518                                                         << PP(p_under) << "; not digging." << std::endl;
1519                                         is_valid_dig = false;
1520                                         // Call callbacks
1521                                         m_script->on_cheat(playersao, "finished_unknown_dig");
1522                                 }
1523                                 // Get player's wielded item
1524                                 ItemStack playeritem;
1525                                 InventoryList *mlist = playersao->getInventory()->getList("main");
1526                                 if (mlist != NULL)
1527                                         playeritem = mlist->getItem(playersao->getWieldIndex());
1528                                 ToolCapabilities playeritem_toolcap =
1529                                                 playeritem.getToolCapabilities(m_itemdef);
1530                                 // Get diggability and expected digging time
1531                                 DigParams params = getDigParams(m_nodedef->get(n).groups,
1532                                                 &playeritem_toolcap);
1533                                 // If can't dig, try hand
1534                                 if (!params.diggable) {
1535                                         const ItemDefinition &hand = m_itemdef->get("");
1536                                         const ToolCapabilities *tp = hand.tool_capabilities;
1537                                         if (tp)
1538                                                 params = getDigParams(m_nodedef->get(n).groups, tp);
1539                                 }
1540                                 // If can't dig, ignore dig
1541                                 if (!params.diggable) {
1542                                         infostream << "Server: NoCheat: " << player->getName()
1543                                                         << " completed digging " << PP(p_under)
1544                                                         << ", which is not diggable with tool. not digging."
1545                                                         << std::endl;
1546                                         is_valid_dig = false;
1547                                         // Call callbacks
1548                                         m_script->on_cheat(playersao, "dug_unbreakable");
1549                                 }
1550                                 // Check digging time
1551                                 // If already invalidated, we don't have to
1552                                 if (!is_valid_dig) {
1553                                         // Well not our problem then
1554                                 }
1555                                 // Clean and long dig
1556                                 else if (params.time > 2.0 && nocheat_t * 1.2 > params.time) {
1557                                         // All is good, but grab time from pool; don't care if
1558                                         // it's actually available
1559                                         playersao->getDigPool().grab(params.time);
1560                                 }
1561                                 // Short or laggy dig
1562                                 // Try getting the time from pool
1563                                 else if (playersao->getDigPool().grab(params.time)) {
1564                                         // All is good
1565                                 }
1566                                 // Dig not possible
1567                                 else {
1568                                         infostream << "Server: NoCheat: " << player->getName()
1569                                                         << " completed digging " << PP(p_under)
1570                                                         << "too fast; not digging." << std::endl;
1571                                         is_valid_dig = false;
1572                                         // Call callbacks
1573                                         m_script->on_cheat(playersao, "dug_too_fast");
1574                                 }
1575                         }
1576
1577                         /* Actually dig node */
1578
1579                         if (is_valid_dig && n.getContent() != CONTENT_IGNORE)
1580                                 m_script->node_on_dig(p_under, n, playersao);
1581
1582                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1583                         RemoteClient *client = getClient(pkt->getPeerId());
1584                         // Send unusual result (that is, node not being removed)
1585                         if (m_env->getMap().getNodeNoEx(p_under).getContent() != CONTENT_AIR) {
1586                                 // Re-send block to revert change on client-side
1587                                 client->SetBlockNotSent(blockpos);
1588                         }
1589                         else {
1590                                 client->ResendBlockIfOnWire(blockpos);
1591                         }
1592                 }
1593         } // action == 2
1594
1595         /*
1596                 3: place block or right-click object
1597         */
1598         else if (action == 3) {
1599                 ItemStack item = playersao->getWieldedItem();
1600
1601                 // Reset build time counter
1602                 if (pointed.type == POINTEDTHING_NODE &&
1603                                 item.getDefinition(m_itemdef).type == ITEM_NODE)
1604                         getClient(pkt->getPeerId())->m_time_from_building = 0.0;
1605
1606                 if (pointed.type == POINTEDTHING_OBJECT) {
1607                         // Right click object
1608
1609                         // Skip if object has been removed
1610                         if (pointed_object->m_removed)
1611                                 return;
1612
1613                         actionstream << player->getName() << " right-clicks object "
1614                                         << pointed.object_id << ": "
1615                                         << pointed_object->getDescription() << std::endl;
1616
1617                         // Do stuff
1618                         pointed_object->rightClick(playersao);
1619                 }
1620                 else if (m_script->item_OnPlace(
1621                                 item, playersao, pointed)) {
1622                         // Placement was handled in lua
1623
1624                         // Apply returned ItemStack
1625                         if (playersao->setWieldedItem(item)) {
1626                                 SendInventory(playersao);
1627                         }
1628                 }
1629
1630                 // If item has node placement prediction, always send the
1631                 // blocks to make sure the client knows what exactly happened
1632                 RemoteClient *client = getClient(pkt->getPeerId());
1633                 v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_above, BS));
1634                 v3s16 blockpos2 = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1635                 if (item.getDefinition(m_itemdef).node_placement_prediction != "") {
1636                         client->SetBlockNotSent(blockpos);
1637                         if (blockpos2 != blockpos) {
1638                                 client->SetBlockNotSent(blockpos2);
1639                         }
1640                 }
1641                 else {
1642                         client->ResendBlockIfOnWire(blockpos);
1643                         if (blockpos2 != blockpos) {
1644                                 client->ResendBlockIfOnWire(blockpos2);
1645                         }
1646                 }
1647         } // action == 3
1648
1649         /*
1650                 4: use
1651         */
1652         else if (action == 4) {
1653                 ItemStack item = playersao->getWieldedItem();
1654
1655                 actionstream << player->getName() << " uses " << item.name
1656                                 << ", pointing at " << pointed.dump() << std::endl;
1657
1658                 if (m_script->item_OnUse(
1659                                 item, playersao, pointed)) {
1660                         // Apply returned ItemStack
1661                         if (playersao->setWieldedItem(item)) {
1662                                 SendInventory(playersao);
1663                         }
1664                 }
1665
1666         } // action == 4
1667
1668         /*
1669                 5: rightclick air
1670         */
1671         else if (action == 5) {
1672                 ItemStack item = playersao->getWieldedItem();
1673
1674                 actionstream << player->getName() << " activates "
1675                                 << item.name << std::endl;
1676
1677                 if (m_script->item_OnSecondaryUse(
1678                                 item, playersao)) {
1679                         if( playersao->setWieldedItem(item)) {
1680                                 SendInventory(playersao);
1681                         }
1682                 }
1683         }
1684
1685
1686         /*
1687                 Catch invalid actions
1688         */
1689         else {
1690                 warningstream << "Server: Invalid action "
1691                                 << action << std::endl;
1692         }
1693 }
1694
1695 void Server::handleCommand_RemovedSounds(NetworkPacket* pkt)
1696 {
1697         u16 num;
1698         *pkt >> num;
1699         for (u16 k = 0; k < num; k++) {
1700                 s32 id;
1701
1702                 *pkt >> id;
1703
1704                 UNORDERED_MAP<s32, ServerPlayingSound>::iterator i = m_playing_sounds.find(id);
1705                 if (i == m_playing_sounds.end())
1706                         continue;
1707
1708                 ServerPlayingSound &psound = i->second;
1709                 psound.clients.erase(pkt->getPeerId());
1710                 if (psound.clients.empty())
1711                         m_playing_sounds.erase(i++);
1712         }
1713 }
1714
1715 void Server::handleCommand_NodeMetaFields(NetworkPacket* pkt)
1716 {
1717         v3s16 p;
1718         std::string formname;
1719         u16 num;
1720
1721         *pkt >> p >> formname >> num;
1722
1723         StringMap fields;
1724         for (u16 k = 0; k < num; k++) {
1725                 std::string fieldname;
1726                 *pkt >> fieldname;
1727                 fields[fieldname] = pkt->readLongString();
1728         }
1729
1730         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
1731
1732         if (player == NULL) {
1733                 errorstream << "Server::ProcessData(): Canceling: "
1734                                 "No player for peer_id=" << pkt->getPeerId()
1735                                 << " disconnecting peer!" << std::endl;
1736                 m_con.DisconnectPeer(pkt->getPeerId());
1737                 return;
1738         }
1739
1740         PlayerSAO *playersao = player->getPlayerSAO();
1741         if (playersao == NULL) {
1742                 errorstream << "Server::ProcessData(): Canceling: "
1743                                 "No player object for peer_id=" << pkt->getPeerId()
1744                                 << " disconnecting peer!"  << std::endl;
1745                 m_con.DisconnectPeer(pkt->getPeerId());
1746                 return;
1747         }
1748
1749         // If something goes wrong, this player is to blame
1750         RollbackScopeActor rollback_scope(m_rollback,
1751                         std::string("player:")+player->getName());
1752
1753         // Check the target node for rollback data; leave others unnoticed
1754         RollbackNode rn_old(&m_env->getMap(), p, this);
1755
1756         m_script->node_on_receive_fields(p, formname, fields, playersao);
1757
1758         // Report rollback data
1759         RollbackNode rn_new(&m_env->getMap(), p, this);
1760         if (rollback() && rn_new != rn_old) {
1761                 RollbackAction action;
1762                 action.setSetNode(p, rn_old, rn_new);
1763                 rollback()->reportAction(action);
1764         }
1765 }
1766
1767 void Server::handleCommand_InventoryFields(NetworkPacket* pkt)
1768 {
1769         std::string formname;
1770         u16 num;
1771
1772         *pkt >> formname >> num;
1773
1774         StringMap fields;
1775         for (u16 k = 0; k < num; k++) {
1776                 std::string fieldname;
1777                 *pkt >> fieldname;
1778                 fields[fieldname] = pkt->readLongString();
1779         }
1780
1781         RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
1782
1783         if (player == NULL) {
1784                 errorstream << "Server::ProcessData(): Canceling: "
1785                                 "No player for peer_id=" << pkt->getPeerId()
1786                                 << " disconnecting peer!" << std::endl;
1787                 m_con.DisconnectPeer(pkt->getPeerId());
1788                 return;
1789         }
1790
1791         PlayerSAO *playersao = player->getPlayerSAO();
1792         if (playersao == NULL) {
1793                 errorstream << "Server::ProcessData(): Canceling: "
1794                                 "No player object for peer_id=" << pkt->getPeerId()
1795                                 << " disconnecting peer!" << std::endl;
1796                 m_con.DisconnectPeer(pkt->getPeerId());
1797                 return;
1798         }
1799
1800         m_script->on_playerReceiveFields(playersao, formname, fields);
1801 }
1802
1803 void Server::handleCommand_FirstSrp(NetworkPacket* pkt)
1804 {
1805         RemoteClient* client = getClient(pkt->getPeerId(), CS_Invalid);
1806         ClientState cstate = client->getState();
1807
1808         std::string playername = client->getName();
1809
1810         std::string salt;
1811         std::string verification_key;
1812
1813         std::string addr_s = getPeerAddress(pkt->getPeerId()).serializeString();
1814         u8 is_empty;
1815
1816         *pkt >> salt >> verification_key >> is_empty;
1817
1818         verbosestream << "Server: Got TOSERVER_FIRST_SRP from " << addr_s
1819                 << ", with is_empty=" << (is_empty == 1) << std::endl;
1820
1821         // Either this packet is sent because the user is new or to change the password
1822         if (cstate == CS_HelloSent) {
1823                 if (!client->isMechAllowed(AUTH_MECHANISM_FIRST_SRP)) {
1824                         actionstream << "Server: Client from " << addr_s
1825                                         << " tried to set password without being "
1826                                         << "authenticated, or the username being new." << std::endl;
1827                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1828                         return;
1829                 }
1830
1831                 if (!isSingleplayer() &&
1832                                 g_settings->getBool("disallow_empty_password") &&
1833                                 is_empty == 1) {
1834                         actionstream << "Server: " << playername
1835                                         << " supplied empty password from " << addr_s << std::endl;
1836                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_EMPTY_PASSWORD);
1837                         return;
1838                 }
1839
1840                 std::string initial_ver_key;
1841
1842                 initial_ver_key = encode_srp_verifier(verification_key, salt);
1843                 m_script->createAuth(playername, initial_ver_key);
1844
1845                 acceptAuth(pkt->getPeerId(), false);
1846         } else {
1847                 if (cstate < CS_SudoMode) {
1848                         infostream << "Server::ProcessData(): Ignoring TOSERVER_FIRST_SRP from "
1849                                         << addr_s << ": " << "Client has wrong state " << cstate << "."
1850                                         << std::endl;
1851                         return;
1852                 }
1853                 m_clients.event(pkt->getPeerId(), CSE_SudoLeave);
1854                 std::string pw_db_field = encode_srp_verifier(verification_key, salt);
1855                 bool success = m_script->setPassword(playername, pw_db_field);
1856                 if (success) {
1857                         actionstream << playername << " changes password" << std::endl;
1858                         SendChatMessage(pkt->getPeerId(), L"Password change successful.");
1859                 } else {
1860                         actionstream << playername << " tries to change password but "
1861                                 << "it fails" << std::endl;
1862                         SendChatMessage(pkt->getPeerId(), L"Password change failed or unavailable.");
1863                 }
1864         }
1865 }
1866
1867 void Server::handleCommand_SrpBytesA(NetworkPacket* pkt)
1868 {
1869         RemoteClient* client = getClient(pkt->getPeerId(), CS_Invalid);
1870         ClientState cstate = client->getState();
1871
1872         bool wantSudo = (cstate == CS_Active);
1873
1874         if (!((cstate == CS_HelloSent) || (cstate == CS_Active))) {
1875                 actionstream << "Server: got SRP _A packet in wrong state "
1876                         << cstate << " from "
1877                         << getPeerAddress(pkt->getPeerId()).serializeString()
1878                         << ". Ignoring." << std::endl;
1879                 return;
1880         }
1881
1882         if (client->chosen_mech != AUTH_MECHANISM_NONE) {
1883                 actionstream << "Server: got SRP _A packet, while auth"
1884                         << "is already going on with mech " << client->chosen_mech
1885                         << " from " << getPeerAddress(pkt->getPeerId()).serializeString()
1886                         << " (wantSudo=" << wantSudo << "). Ignoring." << std::endl;
1887                 if (wantSudo) {
1888                         DenySudoAccess(pkt->getPeerId());
1889                         return;
1890                 } else {
1891                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1892                         return;
1893                 }
1894         }
1895
1896         std::string bytes_A;
1897         u8 based_on;
1898         *pkt >> bytes_A >> based_on;
1899
1900         infostream << "Server: TOSERVER_SRP_BYTES_A received with "
1901                 << "based_on=" << int(based_on) << " and len_A="
1902                 << bytes_A.length() << "." << std::endl;
1903
1904         AuthMechanism chosen = (based_on == 0) ?
1905                 AUTH_MECHANISM_LEGACY_PASSWORD : AUTH_MECHANISM_SRP;
1906
1907         if (wantSudo) {
1908                 if (!client->isSudoMechAllowed(chosen)) {
1909                         actionstream << "Server: Player \"" << client->getName()
1910                                 << "\" at " << getPeerAddress(pkt->getPeerId()).serializeString()
1911                                 << " tried to change password using unallowed mech "
1912                                 << chosen << "." << std::endl;
1913                         DenySudoAccess(pkt->getPeerId());
1914                         return;
1915                 }
1916         } else {
1917                 if (!client->isMechAllowed(chosen)) {
1918                         actionstream << "Server: Client tried to authenticate from "
1919                                 << getPeerAddress(pkt->getPeerId()).serializeString()
1920                                 << " using unallowed mech " << chosen << "." << std::endl;
1921                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1922                         return;
1923                 }
1924         }
1925
1926         client->chosen_mech = chosen;
1927
1928         std::string salt;
1929         std::string verifier;
1930
1931         if (based_on == 0) {
1932
1933                 generate_srp_verifier_and_salt(client->getName(), client->enc_pwd,
1934                         &verifier, &salt);
1935         } else if (!decode_srp_verifier_and_salt(client->enc_pwd, &verifier, &salt)) {
1936                 // Non-base64 errors should have been catched in the init handler
1937                 actionstream << "Server: User " << client->getName()
1938                         << " tried to log in, but srp verifier field"
1939                         << " was invalid (most likely invalid base64)." << std::endl;
1940                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_SERVER_FAIL);
1941                 return;
1942         }
1943
1944         char *bytes_B = 0;
1945         size_t len_B = 0;
1946
1947         client->auth_data = srp_verifier_new(SRP_SHA256, SRP_NG_2048,
1948                 client->getName().c_str(),
1949                 (const unsigned char *) salt.c_str(), salt.size(),
1950                 (const unsigned char *) verifier.c_str(), verifier.size(),
1951                 (const unsigned char *) bytes_A.c_str(), bytes_A.size(),
1952                 NULL, 0,
1953                 (unsigned char **) &bytes_B, &len_B, NULL, NULL);
1954
1955         if (!bytes_B) {
1956                 actionstream << "Server: User " << client->getName()
1957                         << " tried to log in, SRP-6a safety check violated in _A handler."
1958                         << std::endl;
1959                 if (wantSudo) {
1960                         DenySudoAccess(pkt->getPeerId());
1961                         return;
1962                 } else {
1963                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1964                         return;
1965                 }
1966         }
1967
1968         NetworkPacket resp_pkt(TOCLIENT_SRP_BYTES_S_B, 0, pkt->getPeerId());
1969         resp_pkt << salt << std::string(bytes_B, len_B);
1970         Send(&resp_pkt);
1971 }
1972
1973 void Server::handleCommand_SrpBytesM(NetworkPacket* pkt)
1974 {
1975         RemoteClient* client = getClient(pkt->getPeerId(), CS_Invalid);
1976         ClientState cstate = client->getState();
1977
1978         bool wantSudo = (cstate == CS_Active);
1979
1980         verbosestream << "Server: Recieved TOCLIENT_SRP_BYTES_M." << std::endl;
1981
1982         if (!((cstate == CS_HelloSent) || (cstate == CS_Active))) {
1983                 actionstream << "Server: got SRP _M packet in wrong state "
1984                         << cstate << " from "
1985                         << getPeerAddress(pkt->getPeerId()).serializeString()
1986                         << ". Ignoring." << std::endl;
1987                 return;
1988         }
1989
1990         if ((client->chosen_mech != AUTH_MECHANISM_SRP)
1991                 && (client->chosen_mech != AUTH_MECHANISM_LEGACY_PASSWORD)) {
1992                 actionstream << "Server: got SRP _M packet, while auth"
1993                         << "is going on with mech " << client->chosen_mech
1994                         << " from " << getPeerAddress(pkt->getPeerId()).serializeString()
1995                         << " (wantSudo=" << wantSudo << "). Denying." << std::endl;
1996                 if (wantSudo) {
1997                         DenySudoAccess(pkt->getPeerId());
1998                         return;
1999                 } else {
2000                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
2001                         return;
2002                 }
2003         }
2004
2005         std::string bytes_M;
2006         *pkt >> bytes_M;
2007
2008         if (srp_verifier_get_session_key_length((SRPVerifier *) client->auth_data)
2009                         != bytes_M.size()) {
2010                 actionstream << "Server: User " << client->getName()
2011                         << " at " << getPeerAddress(pkt->getPeerId()).serializeString()
2012                         << " sent bytes_M with invalid length " << bytes_M.size() << std::endl;
2013                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
2014                 return;
2015         }
2016
2017         unsigned char *bytes_HAMK = 0;
2018
2019         srp_verifier_verify_session((SRPVerifier *) client->auth_data,
2020                 (unsigned char *)bytes_M.c_str(), &bytes_HAMK);
2021
2022         if (!bytes_HAMK) {
2023                 if (wantSudo) {
2024                         actionstream << "Server: User " << client->getName()
2025                                 << " at " << getPeerAddress(pkt->getPeerId()).serializeString()
2026                                 << " tried to change their password, but supplied wrong"
2027                                 << " (SRP) password for authentication." << std::endl;
2028                         DenySudoAccess(pkt->getPeerId());
2029                         return;
2030                 } else {
2031                         actionstream << "Server: User " << client->getName()
2032                                 << " at " << getPeerAddress(pkt->getPeerId()).serializeString()
2033                                 << " supplied wrong password (auth mechanism: SRP)."
2034                                 << std::endl;
2035                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_PASSWORD);
2036                         return;
2037                 }
2038         }
2039
2040         if (client->create_player_on_auth_success) {
2041                 std::string playername = client->getName();
2042                 m_script->createAuth(playername, client->enc_pwd);
2043
2044                 std::string checkpwd; // not used, but needed for passing something
2045                 if (!m_script->getAuth(playername, &checkpwd, NULL)) {
2046                         actionstream << "Server: " << playername << " cannot be authenticated"
2047                                 << " (auth handler does not work?)" << std::endl;
2048                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_SERVER_FAIL);
2049                         return;
2050                 }
2051                 client->create_player_on_auth_success = false;
2052         }
2053
2054         acceptAuth(pkt->getPeerId(), wantSudo);
2055 }