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[dragonfireclient.git] / 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         Player *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         // If player is dead we don't care of this packet
813         if (player->isDead()) {
814                 verbosestream << "TOSERVER_PLAYERPOS: " << player->getName()
815                         << " is dead. Ignoring packet";
816                 return;
817         }
818
819         PlayerSAO *playersao = player->getPlayerSAO();
820         if (playersao == NULL) {
821                 errorstream << "Server::ProcessData(): Canceling: "
822                                 "No player object for peer_id=" << pkt->getPeerId()
823                                 << " disconnecting peer!" << std::endl;
824                 m_con.DisconnectPeer(pkt->getPeerId());
825                 return;
826         }
827
828         player->setPosition(position);
829         player->setSpeed(speed);
830         player->setPitch(pitch);
831         player->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         Player *player = m_env->getPlayer(pkt->getPeerId());
883         if (player == NULL) {
884                 errorstream << "Server::ProcessData(): Canceling: "
885                                 "No player for peer_id=" << pkt->getPeerId()
886                                 << " disconnecting peer!" << std::endl;
887                 m_con.DisconnectPeer(pkt->getPeerId());
888                 return;
889         }
890
891         PlayerSAO *playersao = player->getPlayerSAO();
892         if (playersao == NULL) {
893                 errorstream << "Server::ProcessData(): Canceling: "
894                                 "No player object for peer_id=" << pkt->getPeerId()
895                                 << " disconnecting peer!" << std::endl;
896                 m_con.DisconnectPeer(pkt->getPeerId());
897                 return;
898         }
899
900         // Strip command and create a stream
901         std::string datastring(pkt->getString(0), pkt->getSize());
902         verbosestream << "TOSERVER_INVENTORY_ACTION: data=" << datastring
903                 << std::endl;
904         std::istringstream is(datastring, std::ios_base::binary);
905         // Create an action
906         InventoryAction *a = InventoryAction::deSerialize(is);
907         if (a == NULL) {
908                 infostream << "TOSERVER_INVENTORY_ACTION: "
909                                 << "InventoryAction::deSerialize() returned NULL"
910                                 << std::endl;
911                 return;
912         }
913
914         // If something goes wrong, this player is to blame
915         RollbackScopeActor rollback_scope(m_rollback,
916                         std::string("player:")+player->getName());
917
918         /*
919                 Note: Always set inventory not sent, to repair cases
920                 where the client made a bad prediction.
921         */
922
923         /*
924                 Handle restrictions and special cases of the move action
925         */
926         if (a->getType() == IACTION_MOVE) {
927                 IMoveAction *ma = (IMoveAction*)a;
928
929                 ma->from_inv.applyCurrentPlayer(player->getName());
930                 ma->to_inv.applyCurrentPlayer(player->getName());
931
932                 setInventoryModified(ma->from_inv, false);
933                 setInventoryModified(ma->to_inv, false);
934
935                 bool from_inv_is_current_player =
936                         (ma->from_inv.type == InventoryLocation::PLAYER) &&
937                         (ma->from_inv.name == player->getName());
938
939                 bool to_inv_is_current_player =
940                         (ma->to_inv.type == InventoryLocation::PLAYER) &&
941                         (ma->to_inv.name == player->getName());
942
943                 /*
944                         Disable moving items out of craftpreview
945                 */
946                 if (ma->from_list == "craftpreview") {
947                         infostream << "Ignoring IMoveAction from "
948                                         << (ma->from_inv.dump()) << ":" << ma->from_list
949                                         << " to " << (ma->to_inv.dump()) << ":" << ma->to_list
950                                         << " because src is " << ma->from_list << std::endl;
951                         delete a;
952                         return;
953                 }
954
955                 /*
956                         Disable moving items into craftresult and craftpreview
957                 */
958                 if (ma->to_list == "craftpreview" || ma->to_list == "craftresult") {
959                         infostream << "Ignoring IMoveAction from "
960                                         << (ma->from_inv.dump()) << ":" << ma->from_list
961                                         << " to " << (ma->to_inv.dump()) << ":" << ma->to_list
962                                         << " because dst is " << ma->to_list << std::endl;
963                         delete a;
964                         return;
965                 }
966
967                 // Disallow moving items in elsewhere than player's inventory
968                 // if not allowed to interact
969                 if (!checkPriv(player->getName(), "interact") &&
970                                 (!from_inv_is_current_player ||
971                                 !to_inv_is_current_player)) {
972                         infostream << "Cannot move outside of player's inventory: "
973                                         << "No interact privilege" << std::endl;
974                         delete a;
975                         return;
976                 }
977         }
978         /*
979                 Handle restrictions and special cases of the drop action
980         */
981         else if (a->getType() == IACTION_DROP) {
982                 IDropAction *da = (IDropAction*)a;
983
984                 da->from_inv.applyCurrentPlayer(player->getName());
985
986                 setInventoryModified(da->from_inv, false);
987
988                 /*
989                         Disable dropping items out of craftpreview
990                 */
991                 if (da->from_list == "craftpreview") {
992                         infostream << "Ignoring IDropAction from "
993                                         << (da->from_inv.dump()) << ":" << da->from_list
994                                         << " because src is " << da->from_list << std::endl;
995                         delete a;
996                         return;
997                 }
998
999                 // Disallow dropping items if not allowed to interact
1000                 if (!checkPriv(player->getName(), "interact")) {
1001                         delete a;
1002                         return;
1003                 }
1004         }
1005         /*
1006                 Handle restrictions and special cases of the craft action
1007         */
1008         else if (a->getType() == IACTION_CRAFT) {
1009                 ICraftAction *ca = (ICraftAction*)a;
1010
1011                 ca->craft_inv.applyCurrentPlayer(player->getName());
1012
1013                 setInventoryModified(ca->craft_inv, false);
1014
1015                 //bool craft_inv_is_current_player =
1016                 //      (ca->craft_inv.type == InventoryLocation::PLAYER) &&
1017                 //      (ca->craft_inv.name == player->getName());
1018
1019                 // Disallow crafting if not allowed to interact
1020                 if (!checkPriv(player->getName(), "interact")) {
1021                         infostream << "Cannot craft: "
1022                                         << "No interact privilege" << std::endl;
1023                         delete a;
1024                         return;
1025                 }
1026         }
1027
1028         // Do the action
1029         a->apply(this, playersao, this);
1030         // Eat the action
1031         delete a;
1032
1033         SendInventory(playersao);
1034 }
1035
1036 void Server::handleCommand_ChatMessage(NetworkPacket* pkt)
1037 {
1038         /*
1039                 u16 command
1040                 u16 length
1041                 wstring message
1042         */
1043         u16 len;
1044         *pkt >> len;
1045
1046         std::wstring message;
1047         for (u16 i = 0; i < len; i++) {
1048                 u16 tmp_wchar;
1049                 *pkt >> tmp_wchar;
1050
1051                 message += (wchar_t)tmp_wchar;
1052         }
1053
1054         Player *player = m_env->getPlayer(pkt->getPeerId());
1055         if (player == NULL) {
1056                 errorstream << "Server::ProcessData(): Canceling: "
1057                                 "No player for peer_id=" << pkt->getPeerId()
1058                                 << " disconnecting peer!" << std::endl;
1059                 m_con.DisconnectPeer(pkt->getPeerId());
1060                 return;
1061         }
1062
1063         // Get player name of this client
1064         std::string name = player->getName();
1065         std::wstring wname = narrow_to_wide(name);
1066
1067         std::wstring answer_to_sender = handleChat(name, wname, message,
1068                 true, dynamic_cast<RemotePlayer *>(player));
1069         if (!answer_to_sender.empty()) {
1070                 // Send the answer to sender
1071                 SendChatMessage(pkt->getPeerId(), answer_to_sender);
1072         }
1073 }
1074
1075 void Server::handleCommand_Damage(NetworkPacket* pkt)
1076 {
1077         u8 damage;
1078
1079         *pkt >> damage;
1080
1081         Player *player = m_env->getPlayer(pkt->getPeerId());
1082         if (player == NULL) {
1083                 errorstream << "Server::ProcessData(): Canceling: "
1084                                 "No player for peer_id=" << pkt->getPeerId()
1085                                 << " disconnecting peer!" << std::endl;
1086                 m_con.DisconnectPeer(pkt->getPeerId());
1087                 return;
1088         }
1089
1090         PlayerSAO *playersao = player->getPlayerSAO();
1091         if (playersao == NULL) {
1092                 errorstream << "Server::ProcessData(): Canceling: "
1093                                 "No player object for peer_id=" << pkt->getPeerId()
1094                                 << " disconnecting peer!" << std::endl;
1095                 m_con.DisconnectPeer(pkt->getPeerId());
1096                 return;
1097         }
1098
1099         if (g_settings->getBool("enable_damage")) {
1100                 actionstream << player->getName() << " damaged by "
1101                                 << (int)damage << " hp at " << PP(player->getPosition() / BS)
1102                                 << std::endl;
1103
1104                 playersao->setHP(playersao->getHP() - damage);
1105                 SendPlayerHPOrDie(playersao);
1106         }
1107 }
1108
1109 void Server::handleCommand_Breath(NetworkPacket* pkt)
1110 {
1111         u16 breath;
1112
1113         *pkt >> breath;
1114
1115         Player *player = m_env->getPlayer(pkt->getPeerId());
1116         if (player == NULL) {
1117                 errorstream << "Server::ProcessData(): Canceling: "
1118                                 "No player for peer_id=" << pkt->getPeerId()
1119                                 << " disconnecting peer!" << std::endl;
1120                 m_con.DisconnectPeer(pkt->getPeerId());
1121                 return;
1122         }
1123
1124         /*
1125          * If player is dead, we don't need to update the breath
1126          * He is dead !
1127          */
1128         if (player->isDead()) {
1129                 verbosestream << "TOSERVER_BREATH: " << player->getName()
1130                         << " is dead. Ignoring packet";
1131                 return;
1132         }
1133
1134
1135         PlayerSAO *playersao = player->getPlayerSAO();
1136         if (playersao == NULL) {
1137                 errorstream << "Server::ProcessData(): Canceling: "
1138                                 "No player object for peer_id=" << pkt->getPeerId()
1139                                 << " disconnecting peer!" << std::endl;
1140                 m_con.DisconnectPeer(pkt->getPeerId());
1141                 return;
1142         }
1143
1144         playersao->setBreath(breath);
1145         SendPlayerBreath(pkt->getPeerId());
1146 }
1147
1148 void Server::handleCommand_Password(NetworkPacket* pkt)
1149 {
1150         if (pkt->getSize() != PASSWORD_SIZE * 2)
1151                 return;
1152
1153         std::string oldpwd;
1154         std::string newpwd;
1155
1156         // Deny for clients using the new protocol
1157         RemoteClient* client = getClient(pkt->getPeerId(), CS_Created);
1158         if (client->net_proto_version >= 25) {
1159                 infostream << "Server::handleCommand_Password(): Denying change: "
1160                         << " Client protocol version for peer_id=" << pkt->getPeerId()
1161                         << " too new!" << std::endl;
1162                 return;
1163         }
1164
1165         for (u16 i = 0; i < PASSWORD_SIZE - 1; i++) {
1166                 char c = pkt->getChar(i);
1167                 if (c == 0)
1168                         break;
1169                 oldpwd += c;
1170         }
1171
1172         for (u16 i = 0; i < PASSWORD_SIZE - 1; i++) {
1173                 char c = pkt->getChar(PASSWORD_SIZE + i);
1174                 if (c == 0)
1175                         break;
1176                 newpwd += c;
1177         }
1178
1179         Player *player = m_env->getPlayer(pkt->getPeerId());
1180         if (player == NULL) {
1181                 errorstream << "Server::ProcessData(): Canceling: "
1182                                 "No player for peer_id=" << pkt->getPeerId()
1183                                 << " disconnecting peer!" << std::endl;
1184                 m_con.DisconnectPeer(pkt->getPeerId());
1185                 return;
1186         }
1187
1188         if (!base64_is_valid(newpwd)) {
1189                 infostream<<"Server: " << player->getName() <<
1190                                 " supplied invalid password hash" << std::endl;
1191                 // Wrong old password supplied!!
1192                 SendChatMessage(pkt->getPeerId(), L"Invalid new password hash supplied. Password NOT changed.");
1193                 return;
1194         }
1195
1196         infostream << "Server: Client requests a password change from "
1197                         << "'" << oldpwd << "' to '" << newpwd << "'" << std::endl;
1198
1199         std::string playername = player->getName();
1200
1201         std::string checkpwd;
1202         m_script->getAuth(playername, &checkpwd, NULL);
1203
1204         if (oldpwd != checkpwd) {
1205                 infostream << "Server: invalid old password" << std::endl;
1206                 // Wrong old password supplied!!
1207                 SendChatMessage(pkt->getPeerId(), L"Invalid old password supplied. Password NOT changed.");
1208                 return;
1209         }
1210
1211         bool success = m_script->setPassword(playername, newpwd);
1212         if (success) {
1213                 actionstream << player->getName() << " changes password" << std::endl;
1214                 SendChatMessage(pkt->getPeerId(), L"Password change successful.");
1215         } else {
1216                 actionstream << player->getName() << " tries to change password but "
1217                                 << "it fails" << std::endl;
1218                 SendChatMessage(pkt->getPeerId(), L"Password change failed or unavailable.");
1219         }
1220 }
1221
1222 void Server::handleCommand_PlayerItem(NetworkPacket* pkt)
1223 {
1224         if (pkt->getSize() < 2)
1225                 return;
1226
1227         Player *player = m_env->getPlayer(pkt->getPeerId());
1228         if (player == NULL) {
1229                 errorstream << "Server::ProcessData(): Canceling: "
1230                                 "No player for peer_id=" << pkt->getPeerId()
1231                                 << " disconnecting peer!" << std::endl;
1232                 m_con.DisconnectPeer(pkt->getPeerId());
1233                 return;
1234         }
1235
1236         PlayerSAO *playersao = player->getPlayerSAO();
1237         if (playersao == NULL) {
1238                 errorstream << "Server::ProcessData(): Canceling: "
1239                                 "No player object for peer_id=" << pkt->getPeerId()
1240                                 << " disconnecting peer!" << std::endl;
1241                 m_con.DisconnectPeer(pkt->getPeerId());
1242                 return;
1243         }
1244
1245         u16 item;
1246
1247         *pkt >> item;
1248
1249         playersao->setWieldIndex(item);
1250 }
1251
1252 void Server::handleCommand_Respawn(NetworkPacket* pkt)
1253 {
1254         Player *player = m_env->getPlayer(pkt->getPeerId());
1255         if (player == NULL) {
1256                 errorstream << "Server::ProcessData(): Canceling: "
1257                                 "No player for peer_id=" << pkt->getPeerId()
1258                                 << " disconnecting peer!" << std::endl;
1259                 m_con.DisconnectPeer(pkt->getPeerId());
1260                 return;
1261         }
1262
1263         if (!player->isDead())
1264                 return;
1265
1266         RespawnPlayer(pkt->getPeerId());
1267
1268         actionstream << player->getName() << " respawns at "
1269                         << PP(player->getPosition()/BS) << std::endl;
1270
1271         // ActiveObject is added to environment in AsyncRunStep after
1272         // the previous addition has been successfully removed
1273 }
1274
1275 void Server::handleCommand_Interact(NetworkPacket* pkt)
1276 {
1277         std::string datastring(pkt->getString(0), pkt->getSize());
1278         std::istringstream is(datastring, std::ios_base::binary);
1279
1280         /*
1281                 [0] u16 command
1282                 [2] u8 action
1283                 [3] u16 item
1284                 [5] u32 length of the next item
1285                 [9] serialized PointedThing
1286                 actions:
1287                 0: start digging (from undersurface) or use
1288                 1: stop digging (all parameters ignored)
1289                 2: digging completed
1290                 3: place block or item (to abovesurface)
1291                 4: use item
1292         */
1293         u8 action = readU8(is);
1294         u16 item_i = readU16(is);
1295         std::istringstream tmp_is(deSerializeLongString(is), std::ios::binary);
1296         PointedThing pointed;
1297         pointed.deSerialize(tmp_is);
1298
1299         verbosestream << "TOSERVER_INTERACT: action=" << (int)action << ", item="
1300                         << item_i << ", pointed=" << pointed.dump() << std::endl;
1301
1302         Player *player = m_env->getPlayer(pkt->getPeerId());
1303         if (player == NULL) {
1304                 errorstream << "Server::ProcessData(): Canceling: "
1305                                 "No player for peer_id=" << pkt->getPeerId()
1306                                 << " disconnecting peer!" << std::endl;
1307                 m_con.DisconnectPeer(pkt->getPeerId());
1308                 return;
1309         }
1310
1311         PlayerSAO *playersao = player->getPlayerSAO();
1312         if (playersao == NULL) {
1313                 errorstream << "Server::ProcessData(): Canceling: "
1314                                 "No player object for peer_id=" << pkt->getPeerId()
1315                                 << " disconnecting peer!" << std::endl;
1316                 m_con.DisconnectPeer(pkt->getPeerId());
1317                 return;
1318         }
1319
1320         if (player->isDead()) {
1321                 verbosestream << "TOSERVER_INTERACT: " << player->getName()
1322                         << " is dead. Ignoring packet";
1323                 return;
1324         }
1325
1326         v3f player_pos = playersao->getLastGoodPosition();
1327
1328         // Update wielded item
1329         playersao->setWieldIndex(item_i);
1330
1331         // Get pointed to node (undefined if not POINTEDTYPE_NODE)
1332         v3s16 p_under = pointed.node_undersurface;
1333         v3s16 p_above = pointed.node_abovesurface;
1334
1335         // Get pointed to object (NULL if not POINTEDTYPE_OBJECT)
1336         ServerActiveObject *pointed_object = NULL;
1337         if (pointed.type == POINTEDTHING_OBJECT) {
1338                 pointed_object = m_env->getActiveObject(pointed.object_id);
1339                 if (pointed_object == NULL) {
1340                         verbosestream << "TOSERVER_INTERACT: "
1341                                 "pointed object is NULL" << std::endl;
1342                         return;
1343                 }
1344
1345         }
1346
1347         v3f pointed_pos_under = player_pos;
1348         v3f pointed_pos_above = player_pos;
1349         if (pointed.type == POINTEDTHING_NODE) {
1350                 pointed_pos_under = intToFloat(p_under, BS);
1351                 pointed_pos_above = intToFloat(p_above, BS);
1352         }
1353         else if (pointed.type == POINTEDTHING_OBJECT) {
1354                 pointed_pos_under = pointed_object->getBasePosition();
1355                 pointed_pos_above = pointed_pos_under;
1356         }
1357
1358         /*
1359                 Check that target is reasonably close
1360                 (only when digging or placing things)
1361         */
1362         static const bool enable_anticheat = !g_settings->getBool("disable_anticheat");
1363         if ((action == 0 || action == 2 || action == 3) &&
1364                         (enable_anticheat && !isSingleplayer())) {
1365                 float d = player_pos.getDistanceFrom(pointed_pos_under);
1366                 float max_d = BS * 14; // Just some large enough value
1367                 if (d > max_d) {
1368                         actionstream << "Player " << player->getName()
1369                                         << " tried to access " << pointed.dump()
1370                                         << " from too far: "
1371                                         << "d=" << d <<", max_d=" << max_d
1372                                         << ". ignoring." << std::endl;
1373                         // Re-send block to revert change on client-side
1374                         RemoteClient *client = getClient(pkt->getPeerId());
1375                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1376                         client->SetBlockNotSent(blockpos);
1377                         // Call callbacks
1378                         m_script->on_cheat(playersao, "interacted_too_far");
1379                         // Do nothing else
1380                         return;
1381                 }
1382         }
1383
1384         /*
1385                 Make sure the player is allowed to do it
1386         */
1387         if (!checkPriv(player->getName(), "interact")) {
1388                 actionstream<<player->getName()<<" attempted to interact with "
1389                                 <<pointed.dump()<<" without 'interact' privilege"
1390                                 <<std::endl;
1391                 // Re-send block to revert change on client-side
1392                 RemoteClient *client = getClient(pkt->getPeerId());
1393                 // Digging completed -> under
1394                 if (action == 2) {
1395                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1396                         client->SetBlockNotSent(blockpos);
1397                 }
1398                 // Placement -> above
1399                 if (action == 3) {
1400                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_above, BS));
1401                         client->SetBlockNotSent(blockpos);
1402                 }
1403                 return;
1404         }
1405
1406         /*
1407                 If something goes wrong, this player is to blame
1408         */
1409         RollbackScopeActor rollback_scope(m_rollback,
1410                         std::string("player:")+player->getName());
1411
1412         /*
1413                 0: start digging or punch object
1414         */
1415         if (action == 0) {
1416                 if (pointed.type == POINTEDTHING_NODE) {
1417                         /*
1418                                 NOTE: This can be used in the future to check if
1419                                 somebody is cheating, by checking the timing.
1420                         */
1421
1422                         MapNode n(CONTENT_IGNORE);
1423                         bool pos_ok;
1424
1425                         n = m_env->getMap().getNodeNoEx(p_under, &pos_ok);
1426                         if (!pos_ok) {
1427                                 infostream << "Server: Not punching: Node not found."
1428                                                 << " Adding block to emerge queue."
1429                                                 << std::endl;
1430                                 m_emerge->enqueueBlockEmerge(pkt->getPeerId(),
1431                                         getNodeBlockPos(p_above), false);
1432                         }
1433
1434                         if (n.getContent() != CONTENT_IGNORE)
1435                                 m_script->node_on_punch(p_under, n, playersao, pointed);
1436
1437                         // Cheat prevention
1438                         playersao->noCheatDigStart(p_under);
1439                 }
1440                 else if (pointed.type == POINTEDTHING_OBJECT) {
1441                         // Skip if object has been removed
1442                         if (pointed_object->m_removed)
1443                                 return;
1444
1445                         actionstream<<player->getName()<<" punches object "
1446                                         <<pointed.object_id<<": "
1447                                         <<pointed_object->getDescription()<<std::endl;
1448
1449                         ItemStack punchitem = playersao->getWieldedItem();
1450                         ToolCapabilities toolcap =
1451                                         punchitem.getToolCapabilities(m_itemdef);
1452                         v3f dir = (pointed_object->getBasePosition() -
1453                                         (player->getPosition() + player->getEyeOffset())
1454                                                 ).normalize();
1455                         float time_from_last_punch =
1456                                 playersao->resetTimeFromLastPunch();
1457
1458                         s16 src_original_hp = pointed_object->getHP();
1459                         s16 dst_origin_hp = playersao->getHP();
1460
1461                         pointed_object->punch(dir, &toolcap, playersao,
1462                                         time_from_last_punch);
1463
1464                         // If the object is a player and its HP changed
1465                         if (src_original_hp != pointed_object->getHP() &&
1466                                         pointed_object->getType() == ACTIVEOBJECT_TYPE_PLAYER) {
1467                                 SendPlayerHPOrDie((PlayerSAO *)pointed_object);
1468                         }
1469
1470                         // If the puncher is a player and its HP changed
1471                         if (dst_origin_hp != playersao->getHP())
1472                                 SendPlayerHPOrDie(playersao);
1473                 }
1474
1475         } // action == 0
1476
1477         /*
1478                 1: stop digging
1479         */
1480         else if (action == 1) {
1481         } // action == 1
1482
1483         /*
1484                 2: Digging completed
1485         */
1486         else if (action == 2) {
1487                 // Only digging of nodes
1488                 if (pointed.type == POINTEDTHING_NODE) {
1489                         bool pos_ok;
1490                         MapNode n = m_env->getMap().getNodeNoEx(p_under, &pos_ok);
1491                         if (!pos_ok) {
1492                                 infostream << "Server: Not finishing digging: Node not found."
1493                                                 << " Adding block to emerge queue."
1494                                                 << std::endl;
1495                                 m_emerge->enqueueBlockEmerge(pkt->getPeerId(),
1496                                         getNodeBlockPos(p_above), false);
1497                         }
1498
1499                         /* Cheat prevention */
1500                         bool is_valid_dig = true;
1501                         if (enable_anticheat && !isSingleplayer()) {
1502                                 v3s16 nocheat_p = playersao->getNoCheatDigPos();
1503                                 float nocheat_t = playersao->getNoCheatDigTime();
1504                                 playersao->noCheatDigEnd();
1505                                 // If player didn't start digging this, ignore dig
1506                                 if (nocheat_p != p_under) {
1507                                         infostream << "Server: NoCheat: " << player->getName()
1508                                                         << " started digging "
1509                                                         << PP(nocheat_p) << " and completed digging "
1510                                                         << PP(p_under) << "; not digging." << std::endl;
1511                                         is_valid_dig = false;
1512                                         // Call callbacks
1513                                         m_script->on_cheat(playersao, "finished_unknown_dig");
1514                                 }
1515                                 // Get player's wielded item
1516                                 ItemStack playeritem;
1517                                 InventoryList *mlist = playersao->getInventory()->getList("main");
1518                                 if (mlist != NULL)
1519                                         playeritem = mlist->getItem(playersao->getWieldIndex());
1520                                 ToolCapabilities playeritem_toolcap =
1521                                                 playeritem.getToolCapabilities(m_itemdef);
1522                                 // Get diggability and expected digging time
1523                                 DigParams params = getDigParams(m_nodedef->get(n).groups,
1524                                                 &playeritem_toolcap);
1525                                 // If can't dig, try hand
1526                                 if (!params.diggable) {
1527                                         const ItemDefinition &hand = m_itemdef->get("");
1528                                         const ToolCapabilities *tp = hand.tool_capabilities;
1529                                         if (tp)
1530                                                 params = getDigParams(m_nodedef->get(n).groups, tp);
1531                                 }
1532                                 // If can't dig, ignore dig
1533                                 if (!params.diggable) {
1534                                         infostream << "Server: NoCheat: " << player->getName()
1535                                                         << " completed digging " << PP(p_under)
1536                                                         << ", which is not diggable with tool. not digging."
1537                                                         << std::endl;
1538                                         is_valid_dig = false;
1539                                         // Call callbacks
1540                                         m_script->on_cheat(playersao, "dug_unbreakable");
1541                                 }
1542                                 // Check digging time
1543                                 // If already invalidated, we don't have to
1544                                 if (!is_valid_dig) {
1545                                         // Well not our problem then
1546                                 }
1547                                 // Clean and long dig
1548                                 else if (params.time > 2.0 && nocheat_t * 1.2 > params.time) {
1549                                         // All is good, but grab time from pool; don't care if
1550                                         // it's actually available
1551                                         playersao->getDigPool().grab(params.time);
1552                                 }
1553                                 // Short or laggy dig
1554                                 // Try getting the time from pool
1555                                 else if (playersao->getDigPool().grab(params.time)) {
1556                                         // All is good
1557                                 }
1558                                 // Dig not possible
1559                                 else {
1560                                         infostream << "Server: NoCheat: " << player->getName()
1561                                                         << " completed digging " << PP(p_under)
1562                                                         << "too fast; not digging." << std::endl;
1563                                         is_valid_dig = false;
1564                                         // Call callbacks
1565                                         m_script->on_cheat(playersao, "dug_too_fast");
1566                                 }
1567                         }
1568
1569                         /* Actually dig node */
1570
1571                         if (is_valid_dig && n.getContent() != CONTENT_IGNORE)
1572                                 m_script->node_on_dig(p_under, n, playersao);
1573
1574                         v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1575                         RemoteClient *client = getClient(pkt->getPeerId());
1576                         // Send unusual result (that is, node not being removed)
1577                         if (m_env->getMap().getNodeNoEx(p_under).getContent() != CONTENT_AIR) {
1578                                 // Re-send block to revert change on client-side
1579                                 client->SetBlockNotSent(blockpos);
1580                         }
1581                         else {
1582                                 client->ResendBlockIfOnWire(blockpos);
1583                         }
1584                 }
1585         } // action == 2
1586
1587         /*
1588                 3: place block or right-click object
1589         */
1590         else if (action == 3) {
1591                 ItemStack item = playersao->getWieldedItem();
1592
1593                 // Reset build time counter
1594                 if (pointed.type == POINTEDTHING_NODE &&
1595                                 item.getDefinition(m_itemdef).type == ITEM_NODE)
1596                         getClient(pkt->getPeerId())->m_time_from_building = 0.0;
1597
1598                 if (pointed.type == POINTEDTHING_OBJECT) {
1599                         // Right click object
1600
1601                         // Skip if object has been removed
1602                         if (pointed_object->m_removed)
1603                                 return;
1604
1605                         actionstream << player->getName() << " right-clicks object "
1606                                         << pointed.object_id << ": "
1607                                         << pointed_object->getDescription() << std::endl;
1608
1609                         // Do stuff
1610                         pointed_object->rightClick(playersao);
1611                 }
1612                 else if (m_script->item_OnPlace(
1613                                 item, playersao, pointed)) {
1614                         // Placement was handled in lua
1615
1616                         // Apply returned ItemStack
1617                         if (playersao->setWieldedItem(item)) {
1618                                 SendInventory(playersao);
1619                         }
1620                 }
1621
1622                 // If item has node placement prediction, always send the
1623                 // blocks to make sure the client knows what exactly happened
1624                 RemoteClient *client = getClient(pkt->getPeerId());
1625                 v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_above, BS));
1626                 v3s16 blockpos2 = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
1627                 if (item.getDefinition(m_itemdef).node_placement_prediction != "") {
1628                         client->SetBlockNotSent(blockpos);
1629                         if (blockpos2 != blockpos) {
1630                                 client->SetBlockNotSent(blockpos2);
1631                         }
1632                 }
1633                 else {
1634                         client->ResendBlockIfOnWire(blockpos);
1635                         if (blockpos2 != blockpos) {
1636                                 client->ResendBlockIfOnWire(blockpos2);
1637                         }
1638                 }
1639         } // action == 3
1640
1641         /*
1642                 4: use
1643         */
1644         else if (action == 4) {
1645                 ItemStack item = playersao->getWieldedItem();
1646
1647                 actionstream << player->getName() << " uses " << item.name
1648                                 << ", pointing at " << pointed.dump() << std::endl;
1649
1650                 if (m_script->item_OnUse(
1651                                 item, playersao, pointed)) {
1652                         // Apply returned ItemStack
1653                         if (playersao->setWieldedItem(item)) {
1654                                 SendInventory(playersao);
1655                         }
1656                 }
1657
1658         } // action == 4
1659
1660         /*
1661                 5: rightclick air
1662         */
1663         else if (action == 5) {
1664                 ItemStack item = playersao->getWieldedItem();
1665
1666                 actionstream << player->getName() << " activates "
1667                                 << item.name << std::endl;
1668
1669                 if (m_script->item_OnSecondaryUse(
1670                                 item, playersao)) {
1671                         if( playersao->setWieldedItem(item)) {
1672                                 SendInventory(playersao);
1673                         }
1674                 }
1675         }
1676
1677
1678         /*
1679                 Catch invalid actions
1680         */
1681         else {
1682                 warningstream << "Server: Invalid action "
1683                                 << action << std::endl;
1684         }
1685 }
1686
1687 void Server::handleCommand_RemovedSounds(NetworkPacket* pkt)
1688 {
1689         u16 num;
1690         *pkt >> num;
1691         for (u16 k = 0; k < num; k++) {
1692                 s32 id;
1693
1694                 *pkt >> id;
1695
1696                 UNORDERED_MAP<s32, ServerPlayingSound>::iterator i = m_playing_sounds.find(id);
1697                 if (i == m_playing_sounds.end())
1698                         continue;
1699
1700                 ServerPlayingSound &psound = i->second;
1701                 psound.clients.erase(pkt->getPeerId());
1702                 if (psound.clients.empty())
1703                         m_playing_sounds.erase(i++);
1704         }
1705 }
1706
1707 void Server::handleCommand_NodeMetaFields(NetworkPacket* pkt)
1708 {
1709         v3s16 p;
1710         std::string formname;
1711         u16 num;
1712
1713         *pkt >> p >> formname >> num;
1714
1715         StringMap fields;
1716         for (u16 k = 0; k < num; k++) {
1717                 std::string fieldname;
1718                 *pkt >> fieldname;
1719                 fields[fieldname] = pkt->readLongString();
1720         }
1721
1722         Player *player = m_env->getPlayer(pkt->getPeerId());
1723         if (player == NULL) {
1724                 errorstream << "Server::ProcessData(): Canceling: "
1725                                 "No player for peer_id=" << pkt->getPeerId()
1726                                 << " disconnecting peer!" << std::endl;
1727                 m_con.DisconnectPeer(pkt->getPeerId());
1728                 return;
1729         }
1730
1731         PlayerSAO *playersao = player->getPlayerSAO();
1732         if (playersao == NULL) {
1733                 errorstream << "Server::ProcessData(): Canceling: "
1734                                 "No player object for peer_id=" << pkt->getPeerId()
1735                                 << " disconnecting peer!"  << std::endl;
1736                 m_con.DisconnectPeer(pkt->getPeerId());
1737                 return;
1738         }
1739
1740         // If something goes wrong, this player is to blame
1741         RollbackScopeActor rollback_scope(m_rollback,
1742                         std::string("player:")+player->getName());
1743
1744         // Check the target node for rollback data; leave others unnoticed
1745         RollbackNode rn_old(&m_env->getMap(), p, this);
1746
1747         m_script->node_on_receive_fields(p, formname, fields, playersao);
1748
1749         // Report rollback data
1750         RollbackNode rn_new(&m_env->getMap(), p, this);
1751         if (rollback() && rn_new != rn_old) {
1752                 RollbackAction action;
1753                 action.setSetNode(p, rn_old, rn_new);
1754                 rollback()->reportAction(action);
1755         }
1756 }
1757
1758 void Server::handleCommand_InventoryFields(NetworkPacket* pkt)
1759 {
1760         std::string formname;
1761         u16 num;
1762
1763         *pkt >> formname >> num;
1764
1765         StringMap fields;
1766         for (u16 k = 0; k < num; k++) {
1767                 std::string fieldname;
1768                 *pkt >> fieldname;
1769                 fields[fieldname] = pkt->readLongString();
1770         }
1771
1772         Player *player = m_env->getPlayer(pkt->getPeerId());
1773         if (player == NULL) {
1774                 errorstream << "Server::ProcessData(): Canceling: "
1775                                 "No player for peer_id=" << pkt->getPeerId()
1776                                 << " disconnecting peer!" << std::endl;
1777                 m_con.DisconnectPeer(pkt->getPeerId());
1778                 return;
1779         }
1780
1781         PlayerSAO *playersao = player->getPlayerSAO();
1782         if (playersao == NULL) {
1783                 errorstream << "Server::ProcessData(): Canceling: "
1784                                 "No player object for peer_id=" << pkt->getPeerId()
1785                                 << " disconnecting peer!" << std::endl;
1786                 m_con.DisconnectPeer(pkt->getPeerId());
1787                 return;
1788         }
1789
1790         m_script->on_playerReceiveFields(playersao, formname, fields);
1791 }
1792
1793 void Server::handleCommand_FirstSrp(NetworkPacket* pkt)
1794 {
1795         RemoteClient* client = getClient(pkt->getPeerId(), CS_Invalid);
1796         ClientState cstate = client->getState();
1797
1798         std::string playername = client->getName();
1799
1800         std::string salt;
1801         std::string verification_key;
1802
1803         std::string addr_s = getPeerAddress(pkt->getPeerId()).serializeString();
1804         u8 is_empty;
1805
1806         *pkt >> salt >> verification_key >> is_empty;
1807
1808         verbosestream << "Server: Got TOSERVER_FIRST_SRP from " << addr_s
1809                 << ", with is_empty=" << (is_empty == 1) << std::endl;
1810
1811         // Either this packet is sent because the user is new or to change the password
1812         if (cstate == CS_HelloSent) {
1813                 if (!client->isMechAllowed(AUTH_MECHANISM_FIRST_SRP)) {
1814                         actionstream << "Server: Client from " << addr_s
1815                                         << " tried to set password without being "
1816                                         << "authenticated, or the username being new." << std::endl;
1817                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1818                         return;
1819                 }
1820
1821                 if (!isSingleplayer() &&
1822                                 g_settings->getBool("disallow_empty_password") &&
1823                                 is_empty == 1) {
1824                         actionstream << "Server: " << playername
1825                                         << " supplied empty password from " << addr_s << std::endl;
1826                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_EMPTY_PASSWORD);
1827                         return;
1828                 }
1829
1830                 std::string initial_ver_key;
1831
1832                 initial_ver_key = encode_srp_verifier(verification_key, salt);
1833                 m_script->createAuth(playername, initial_ver_key);
1834
1835                 acceptAuth(pkt->getPeerId(), false);
1836         } else {
1837                 if (cstate < CS_SudoMode) {
1838                         infostream << "Server::ProcessData(): Ignoring TOSERVER_FIRST_SRP from "
1839                                         << addr_s << ": " << "Client has wrong state " << cstate << "."
1840                                         << std::endl;
1841                         return;
1842                 }
1843                 m_clients.event(pkt->getPeerId(), CSE_SudoLeave);
1844                 std::string pw_db_field = encode_srp_verifier(verification_key, salt);
1845                 bool success = m_script->setPassword(playername, pw_db_field);
1846                 if (success) {
1847                         actionstream << playername << " changes password" << std::endl;
1848                         SendChatMessage(pkt->getPeerId(), L"Password change successful.");
1849                 } else {
1850                         actionstream << playername << " tries to change password but "
1851                                 << "it fails" << std::endl;
1852                         SendChatMessage(pkt->getPeerId(), L"Password change failed or unavailable.");
1853                 }
1854         }
1855 }
1856
1857 void Server::handleCommand_SrpBytesA(NetworkPacket* pkt)
1858 {
1859         RemoteClient* client = getClient(pkt->getPeerId(), CS_Invalid);
1860         ClientState cstate = client->getState();
1861
1862         bool wantSudo = (cstate == CS_Active);
1863
1864         if (!((cstate == CS_HelloSent) || (cstate == CS_Active))) {
1865                 actionstream << "Server: got SRP _A packet in wrong state "
1866                         << cstate << " from "
1867                         << getPeerAddress(pkt->getPeerId()).serializeString()
1868                         << ". Ignoring." << std::endl;
1869                 return;
1870         }
1871
1872         if (client->chosen_mech != AUTH_MECHANISM_NONE) {
1873                 actionstream << "Server: got SRP _A packet, while auth"
1874                         << "is already going on with mech " << client->chosen_mech
1875                         << " from " << getPeerAddress(pkt->getPeerId()).serializeString()
1876                         << " (wantSudo=" << wantSudo << "). Ignoring." << std::endl;
1877                 if (wantSudo) {
1878                         DenySudoAccess(pkt->getPeerId());
1879                         return;
1880                 } else {
1881                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1882                         return;
1883                 }
1884         }
1885
1886         std::string bytes_A;
1887         u8 based_on;
1888         *pkt >> bytes_A >> based_on;
1889
1890         infostream << "Server: TOSERVER_SRP_BYTES_A received with "
1891                 << "based_on=" << int(based_on) << " and len_A="
1892                 << bytes_A.length() << "." << std::endl;
1893
1894         AuthMechanism chosen = (based_on == 0) ?
1895                 AUTH_MECHANISM_LEGACY_PASSWORD : AUTH_MECHANISM_SRP;
1896
1897         if (wantSudo) {
1898                 if (!client->isSudoMechAllowed(chosen)) {
1899                         actionstream << "Server: Player \"" << client->getName()
1900                                 << "\" at " << getPeerAddress(pkt->getPeerId()).serializeString()
1901                                 << " tried to change password using unallowed mech "
1902                                 << chosen << "." << std::endl;
1903                         DenySudoAccess(pkt->getPeerId());
1904                         return;
1905                 }
1906         } else {
1907                 if (!client->isMechAllowed(chosen)) {
1908                         actionstream << "Server: Client tried to authenticate from "
1909                                 << getPeerAddress(pkt->getPeerId()).serializeString()
1910                                 << " using unallowed mech " << chosen << "." << std::endl;
1911                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1912                         return;
1913                 }
1914         }
1915
1916         client->chosen_mech = chosen;
1917
1918         std::string salt;
1919         std::string verifier;
1920
1921         if (based_on == 0) {
1922
1923                 generate_srp_verifier_and_salt(client->getName(), client->enc_pwd,
1924                         &verifier, &salt);
1925         } else if (!decode_srp_verifier_and_salt(client->enc_pwd, &verifier, &salt)) {
1926                 // Non-base64 errors should have been catched in the init handler
1927                 actionstream << "Server: User " << client->getName()
1928                         << " tried to log in, but srp verifier field"
1929                         << " was invalid (most likely invalid base64)." << std::endl;
1930                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_SERVER_FAIL);
1931                 return;
1932         }
1933
1934         char *bytes_B = 0;
1935         size_t len_B = 0;
1936
1937         client->auth_data = srp_verifier_new(SRP_SHA256, SRP_NG_2048,
1938                 client->getName().c_str(),
1939                 (const unsigned char *) salt.c_str(), salt.size(),
1940                 (const unsigned char *) verifier.c_str(), verifier.size(),
1941                 (const unsigned char *) bytes_A.c_str(), bytes_A.size(),
1942                 NULL, 0,
1943                 (unsigned char **) &bytes_B, &len_B, NULL, NULL);
1944
1945         if (!bytes_B) {
1946                 actionstream << "Server: User " << client->getName()
1947                         << " tried to log in, SRP-6a safety check violated in _A handler."
1948                         << std::endl;
1949                 if (wantSudo) {
1950                         DenySudoAccess(pkt->getPeerId());
1951                         return;
1952                 } else {
1953                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1954                         return;
1955                 }
1956         }
1957
1958         NetworkPacket resp_pkt(TOCLIENT_SRP_BYTES_S_B, 0, pkt->getPeerId());
1959         resp_pkt << salt << std::string(bytes_B, len_B);
1960         Send(&resp_pkt);
1961 }
1962
1963 void Server::handleCommand_SrpBytesM(NetworkPacket* pkt)
1964 {
1965         RemoteClient* client = getClient(pkt->getPeerId(), CS_Invalid);
1966         ClientState cstate = client->getState();
1967
1968         bool wantSudo = (cstate == CS_Active);
1969
1970         verbosestream << "Server: Recieved TOCLIENT_SRP_BYTES_M." << std::endl;
1971
1972         if (!((cstate == CS_HelloSent) || (cstate == CS_Active))) {
1973                 actionstream << "Server: got SRP _M packet in wrong state "
1974                         << cstate << " from "
1975                         << getPeerAddress(pkt->getPeerId()).serializeString()
1976                         << ". Ignoring." << std::endl;
1977                 return;
1978         }
1979
1980         if ((client->chosen_mech != AUTH_MECHANISM_SRP)
1981                 && (client->chosen_mech != AUTH_MECHANISM_LEGACY_PASSWORD)) {
1982                 actionstream << "Server: got SRP _M packet, while auth"
1983                         << "is going on with mech " << client->chosen_mech
1984                         << " from " << getPeerAddress(pkt->getPeerId()).serializeString()
1985                         << " (wantSudo=" << wantSudo << "). Denying." << std::endl;
1986                 if (wantSudo) {
1987                         DenySudoAccess(pkt->getPeerId());
1988                         return;
1989                 } else {
1990                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
1991                         return;
1992                 }
1993         }
1994
1995         std::string bytes_M;
1996         *pkt >> bytes_M;
1997
1998         if (srp_verifier_get_session_key_length((SRPVerifier *) client->auth_data)
1999                         != bytes_M.size()) {
2000                 actionstream << "Server: User " << client->getName()
2001                         << " at " << getPeerAddress(pkt->getPeerId()).serializeString()
2002                         << " sent bytes_M with invalid length " << bytes_M.size() << std::endl;
2003                 DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
2004                 return;
2005         }
2006
2007         unsigned char *bytes_HAMK = 0;
2008
2009         srp_verifier_verify_session((SRPVerifier *) client->auth_data,
2010                 (unsigned char *)bytes_M.c_str(), &bytes_HAMK);
2011
2012         if (!bytes_HAMK) {
2013                 if (wantSudo) {
2014                         actionstream << "Server: User " << client->getName()
2015                                 << " at " << getPeerAddress(pkt->getPeerId()).serializeString()
2016                                 << " tried to change their password, but supplied wrong"
2017                                 << " (SRP) password for authentication." << std::endl;
2018                         DenySudoAccess(pkt->getPeerId());
2019                         return;
2020                 } else {
2021                         actionstream << "Server: User " << client->getName()
2022                                 << " at " << getPeerAddress(pkt->getPeerId()).serializeString()
2023                                 << " supplied wrong password (auth mechanism: SRP)."
2024                                 << std::endl;
2025                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_PASSWORD);
2026                         return;
2027                 }
2028         }
2029
2030         if (client->create_player_on_auth_success) {
2031                 std::string playername = client->getName();
2032                 m_script->createAuth(playername, client->enc_pwd);
2033
2034                 std::string checkpwd; // not used, but needed for passing something
2035                 if (!m_script->getAuth(playername, &checkpwd, NULL)) {
2036                         actionstream << "Server: " << playername << " cannot be authenticated"
2037                                 << " (auth handler does not work?)" << std::endl;
2038                         DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_SERVER_FAIL);
2039                         return;
2040                 }
2041                 client->create_player_on_auth_success = false;
2042         }
2043
2044         acceptAuth(pkt->getPeerId(), wantSudo);
2045 }