src/ngircd/irc-server.c

   1 /*
   2  * ngIRCd -- The Next Generation IRC Daemon
   3  * Copyright (c)2001-2014 Alexander Barton (alex@barton.de) and Contributors.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  * Please read the file COPYING, README and AUTHORS for more information.
  10  */
  11
  12 #include "portab.h"
  13
  14 /**
  15  * @file
  16  * IRC commands for server links
  17  */
  18
  19 #include <assert.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <strings.h>
  24
  25 #include "conn-func.h"
  26 #include "conn-zip.h"
  27 #include "conf.h"
  28 #include "channel.h"
  29 #include "log.h"
  30 #include "messages.h"
  31 #include "parse.h"
  32 #include "numeric.h"
  33 #include "ngircd.h"
  34 #include "irc-info.h"
  35 #include "irc-write.h"
  36 #include "op.h"
  37
  38 #include "irc-server.h"
  39
  40 /**
  41  * Handler for the IRC "SERVER" command.
  42  *
  43  * @param Client The client from which this command has been received.
  44  * @param Req Request structure with prefix and all parameters.
  45  * @return CONNECTED or DISCONNECTED.
  46  */
  47 GLOBAL bool
  48 IRC_SERVER( CLIENT *Client, REQUEST *Req )
  49 {
  50         char str[100];
  51         CLIENT *from, *c;
  52         int i;
  53
  54         assert( Client != NULL );
  55         assert( Req != NULL );
  56
  57         /* Return an error if this is not a local client */
  58         if (Client_Conn(Client) <= NONE)
  59                 return IRC_WriteErrClient(Client, ERR_UNKNOWNCOMMAND_MSG,
  60                                           Client_ID(Client), Req->command);
  61
  62         if (Client_Type(Client) == CLIENT_GOTPASS ||
  63             Client_Type(Client) == CLIENT_GOTPASS_2813) {
  64                 /* We got a PASS command from the peer, and now a SERVER
  65                  * command: the peer tries to register itself as a server. */
  66                 LogDebug("Connection %d: got SERVER command (new server link) ...",
  67                         Client_Conn(Client));
  68
  69                 if (Req->argc != 2 && Req->argc != 3)
  70                         return IRC_WriteErrClient(Client, ERR_NEEDMOREPARAMS_MSG,
  71                                                   Client_ID(Client),
  72                                                   Req->command);
  73
  74                 /* Get configuration index of new remote server ... */
  75                 for (i = 0; i < MAX_SERVERS; i++)
  76                         if (strcasecmp(Req->argv[0], Conf_Server[i].name) == 0)
  77                                 break;
  78
  79                 /* Make sure the remote server is configured here */
  80                 if (i >= MAX_SERVERS) {
  81                         Log(LOG_ERR,
  82                             "Connection %d: Server \"%s\" not configured here!",
  83                             Client_Conn(Client), Req->argv[0]);
  84                         Conn_Close(Client_Conn(Client), NULL,
  85                                    "Server not configured here", true);
  86                         return DISCONNECTED;
  87                 }
  88
  89                 /* Check server password */
  90                 if (strcmp(Conn_Password(Client_Conn(Client)),
  91                     Conf_Server[i].pwd_in) != 0) {
  92                         Log(LOG_ERR,
  93                             "Connection %d: Got bad password from server \"%s\"!",
  94                             Client_Conn(Client), Req->argv[0]);
  95                         Conn_Close(Client_Conn(Client), NULL,
  96                                    "Bad password", true);
  97                         return DISCONNECTED;
  98                 }
  99
 100                 /* Is there a registered server with this ID? */
 101                 if (!Client_CheckID(Client, Req->argv[0]))
 102                         return DISCONNECTED;
 103
 104                 /* Mark this connection as belonging to an configured server */
 105                 if (!Conf_SetServer(i, Client_Conn(Client)))
 106                         return DISCONNECTED;
 107
 108                 Client_SetID( Client, Req->argv[0] );
 109                 Client_SetHops( Client, 1 );
 110                 Client_SetInfo( Client, Req->argv[Req->argc - 1] );
 111
 112                 /* Is this server registering on our side, or are we connecting to
 113                  * a remote server? */
 114                 if (Client_Token(Client) != TOKEN_OUTBOUND) {
 115                         /* Incoming connection, send user/pass */
 116                         if (!IRC_WriteStrClient(Client, "PASS %s %s",
 117                                                 Conf_Server[i].pwd_out,
 118                                                 NGIRCd_ProtoID)
 119                             || !IRC_WriteStrClient(Client, "SERVER %s 1 :%s",
 120                                                    Conf_ServerName,
 121                                                    Conf_ServerInfo)) {
 122                                     Conn_Close(Client_Conn(Client),
 123                                                "Unexpected server behavior!",
 124                                                NULL, false);
 125                                     return DISCONNECTED;
 126                         }
 127                         Client_SetIntroducer(Client, Client);
 128                         Client_SetToken(Client, 1);
 129                 } else {
 130                         /* outgoing connect, we already sent a SERVER and PASS
 131                          * command to the peer */
 132                         Client_SetToken(Client, atoi(Req->argv[1]));
 133                 }
 134
 135                 /* Check protocol level */
 136                 if (Client_Type(Client) == CLIENT_GOTPASS) {
 137                         /* We got a "simple" PASS command, so the peer is
 138                          * using the protocol as defined in RFC 1459. */
 139                         if (! (Conn_Options(Client_Conn(Client)) & CONN_RFC1459))
 140                                 Log(LOG_INFO,
 141                                     "Switching connection %d (\"%s\") to RFC 1459 compatibility mode.",
 142                                     Client_Conn(Client), Client_ID(Client));
 143                         Conn_SetOption(Client_Conn(Client), CONN_RFC1459);
 144                 }
 145
 146                 Client_SetType(Client, CLIENT_UNKNOWNSERVER);
 147
 148 #ifdef ZLIB
 149                 if (Client_HasFlag(Client, 'Z')
 150                     && !Zip_InitConn(Client_Conn(Client))) {
 151                         Conn_Close(Client_Conn(Client),
 152                                    "Can't initialize compression (zlib)!",
 153                                    NULL, false );
 154                         return DISCONNECTED;
 155                 }
 156 #endif
 157
 158 #ifdef IRCPLUS
 159                 if (Client_HasFlag(Client, 'H')) {
 160                         LogDebug("Peer supports IRC+ extended server handshake ...");
 161                         if (!IRC_Send_ISUPPORT(Client))
 162                                 return DISCONNECTED;
 163                         return IRC_WriteStrClient(Client, RPL_ENDOFMOTD_MSG,
 164                                                   Client_ID(Client));
 165                 } else {
 166 #endif
 167                         if (Conf_MaxNickLength != CLIENT_NICK_LEN_DEFAULT)
 168                                 Log(LOG_CRIT,
 169                                     "Attention: this server uses a non-standard nick length, but the peer doesn't support the IRC+ extended server handshake!");
 170 #ifdef IRCPLUS
 171                 }
 172 #endif
 173
 174                 return IRC_Num_ENDOFMOTD(Client, Req);
 175         }
 176         else if( Client_Type( Client ) == CLIENT_SERVER )
 177         {
 178                 /* New server is being introduced to the network */
 179
 180                 if (Req->argc != 4)
 181                         return IRC_WriteErrClient(Client, ERR_NEEDMOREPARAMS_MSG,
 182                                                   Client_ID(Client), Req->command);
 183
 184                 /* check for existing server with same ID */
 185                 if (!Client_CheckID(Client, Req->argv[0]))
 186                         return DISCONNECTED;
 187
 188                 from = Client_Search( Req->prefix );
 189                 if (! from) {
 190                         /* Uh, Server, that introduced the new server is unknown?! */
 191                         Log(LOG_ALERT,
 192                             "Unknown ID in prefix of SERVER: \"%s\"! (on connection %d)",
 193                             Req->prefix, Client_Conn(Client));
 194                         Conn_Close(Client_Conn(Client), NULL,
 195                                    "Unknown ID in prefix of SERVER", true);
 196                         return DISCONNECTED;
 197                 }
 198
 199                 c = Client_NewRemoteServer(Client, Req->argv[0], from,
 200                                            atoi(Req->argv[1]), atoi(Req->argv[2]),
 201                                            Req->argv[3], true);
 202                 if (!c) {
 203                         Log(LOG_ALERT,
 204                             "Can't create client structure for server! (on connection %d)",
 205                             Client_Conn(Client));
 206                         Conn_Close(Client_Conn(Client), NULL,
 207                                    "Can't allocate client structure for remote server",
 208                                    true);
 209                         return DISCONNECTED;
 210                 }
 211
 212                 if (Client_Hops(c) > 1 && Req->prefix[0])
 213                         snprintf(str, sizeof(str), "connected to %s, ",
 214                                  Client_ID(from));
 215                 else
 216                         strcpy(str, "");
 217                 Log(LOG_NOTICE|LOG_snotice,
 218                     "Server \"%s\" registered (via %s, %s%d hop%s).",
 219                     Client_ID(c), Client_ID(Client), str, Client_Hops(c),
 220                     Client_Hops(c) > 1 ? "s": "" );
 221
 222                 /* notify other servers */
 223                 IRC_WriteStrServersPrefix(Client, from, "SERVER %s %d %d :%s",
 224                                           Client_ID(c), Client_Hops(c) + 1,
 225                                           Client_MyToken(c), Client_Info(c));
 226
 227                 return CONNECTED;
 228         } else
 229                 return IRC_WriteErrClient(Client, ERR_NEEDMOREPARAMS_MSG,
 230                                           Client_ID(Client), Req->command);
 231 } /* IRC_SERVER */
 232
 233 /*
 234  * Handler for the IRC "NJOIN" command.
 235  *
 236  * @param Client The client from which this command has been received.
 237  * @param Req Request structure with prefix and all parameters.
 238  * @return CONNECTED or DISCONNECTED.
 239  */
 240 GLOBAL bool
 241 IRC_NJOIN( CLIENT *Client, REQUEST *Req )
 242 {
 243         char nick_in[COMMAND_LEN], nick_out[COMMAND_LEN], *channame, *ptr, modes[8];
 244         bool is_owner, is_chanadmin, is_op, is_halfop, is_voiced;
 245         CHANNEL *chan;
 246         CLIENT *c;
 247
 248         assert(Client != NULL);
 249         assert(Req != NULL);
 250
 251         strlcpy(nick_in, Req->argv[1], sizeof(nick_in));
 252         strcpy(nick_out, "");
 253
 254         channame = Req->argv[0];
 255
 256         ptr = strtok(nick_in, ",");
 257         while (ptr) {
 258                 is_owner = is_chanadmin = is_op = is_halfop = is_voiced = false;
 259
 260                 /* cut off prefixes */
 261                 while ((*ptr == '~') || (*ptr == '&') || (*ptr == '@') ||
 262                        (*ptr == '%') || (*ptr == '+')) {
 263                         if (*ptr == '~')
 264                                 is_owner = true;
 265                         if (*ptr == '&')
 266                                 is_chanadmin = true;
 267                         if (*ptr == '@')
 268                                 is_op = true;
 269                         if (*ptr == '%')
 270                                 is_halfop = true;
 271                         if (*ptr == '+')
 272                                 is_voiced = true;
 273                         ptr++;
 274                 }
 275
 276                 c = Client_Search(ptr);
 277                 if (!c) {
 278                         /* Client not found? */
 279                         Log(LOG_ERR,
 280                             "Got NJOIN for unknown nick \"%s\" for channel \"%s\"!",
 281                             ptr, channame);
 282                         goto skip_njoin;
 283                 }
 284
 285                 Channel_Join(c, channame);
 286                 chan = Channel_Search(channame);
 287                 assert(chan != NULL);
 288
 289                 if (is_owner)
 290                         Channel_UserModeAdd(chan, c, 'q');
 291                 if (is_chanadmin)
 292                         Channel_UserModeAdd(chan, c, 'a');
 293                 if (is_op)
 294                         Channel_UserModeAdd(chan, c, 'o');
 295                 if (is_halfop)
 296                         Channel_UserModeAdd(chan, c, 'h');
 297                 if (is_voiced)
 298                         Channel_UserModeAdd(chan, c, 'v');
 299
 300                 /* Announce client to the channel */
 301                 IRC_WriteStrChannelPrefix(Client, chan, c, false,
 302                                           "JOIN :%s", channame);
 303
 304                 /* Announce "channel user modes" to the channel, if any */
 305                 strlcpy(modes, Channel_UserModes(chan, c), sizeof(modes));
 306                 if (modes[0])
 307                         IRC_WriteStrChannelPrefix(Client, chan, Client, false,
 308                                                   "MODE %s +%s %s", channame,
 309                                                   modes, Client_ID(c));
 310
 311                 /* Build nick list for forwarding command */
 312                 if (nick_out[0] != '\0')
 313                         strlcat(nick_out, ",", sizeof(nick_out));
 314                 if (is_owner)
 315                         strlcat(nick_out, "~", sizeof(nick_out));
 316                 if (is_chanadmin)
 317                         strlcat(nick_out, "&", sizeof(nick_out));
 318                 if (is_op)
 319                         strlcat(nick_out, "@", sizeof(nick_out));
 320                 if (is_halfop)
 321                         strlcat(nick_out, "%", sizeof(nick_out));
 322                 if (is_voiced)
 323                         strlcat(nick_out, "+", sizeof(nick_out));
 324                 strlcat(nick_out, ptr, sizeof(nick_out));
 325
 326               skip_njoin:
 327                 /* Get next nick, if any ... */
 328                 ptr = strtok(NULL, ",");
 329         }
 330
 331         /* forward to other servers */
 332         if (nick_out[0] != '\0')
 333                 IRC_WriteStrServersPrefix(Client, Client_ThisServer(),
 334                                           "NJOIN %s :%s", Req->argv[0], nick_out);
 335
 336         return CONNECTED;
 337 } /* IRC_NJOIN */
 338
 339 /**
 340  * Handler for the IRC "SQUIT" command.
 341  *
 342  * @param Client The client from which this command has been received.
 343  * @param Req Request structure with prefix and all parameters.
 344  * @return CONNECTED or DISCONNECTED.
 345  */
 346 GLOBAL bool
 347 IRC_SQUIT(CLIENT * Client, REQUEST * Req)
 348 {
 349         char msg[COMMAND_LEN], logmsg[COMMAND_LEN];
 350         CLIENT *from, *target;
 351         CONN_ID con;
 352         int loglevel;
 353
 354         assert(Client != NULL);
 355         assert(Req != NULL);
 356
 357         if (Client_Type(Client) != CLIENT_SERVER
 358             && !Client_HasMode(Client, 'o'))
 359                 return Op_NoPrivileges(Client, Req);
 360
 361         if (Client_Type(Client) == CLIENT_SERVER && Req->prefix) {
 362                 from = Client_Search(Req->prefix);
 363                 if (Client_Type(from) != CLIENT_SERVER
 364                     && !Op_Check(Client, Req))
 365                         return Op_NoPrivileges(Client, Req);
 366         } else
 367                 from = Client;
 368         if (!from)
 369                 return IRC_WriteErrClient(Client, ERR_NOSUCHNICK_MSG,
 370                                           Client_ID(Client), Req->prefix);
 371
 372         if (Client_Type(Client) == CLIENT_USER)
 373                 loglevel = LOG_NOTICE | LOG_snotice;
 374         else
 375                 loglevel = LOG_DEBUG;
 376         Log(loglevel, "Got SQUIT from %s for \"%s\": \"%s\" ...",
 377             Client_ID(from), Req->argv[0], Req->argv[1]);
 378
 379         target = Client_Search(Req->argv[0]);
 380         if (Client_Type(Client) != CLIENT_SERVER &&
 381             target == Client_ThisServer())
 382                 return Op_NoPrivileges(Client, Req);
 383         if (!target) {
 384                 /* The server is (already) unknown */
 385                 Log(LOG_WARNING,
 386                     "Got SQUIT from %s for unknown server \"%s\"!?",
 387                     Client_ID(Client), Req->argv[0]);
 388                 return CONNECTED;
 389         }
 390
 391         con = Client_Conn(target);
 392
 393         if (Req->argv[1][0])
 394                 if (Client_NextHop(from) != Client || con > NONE)
 395                         snprintf(msg, sizeof(msg), "\"%s\" (SQUIT from %s)",
 396                                  Req->argv[1], Client_ID(from));
 397                 else
 398                         strlcpy(msg, Req->argv[1], sizeof(msg));
 399         else
 400                 snprintf(msg, sizeof(msg), "Got SQUIT from %s",
 401                          Client_ID(from));
 402
 403         if (con > NONE) {
 404                 /* We are directly connected to the target server, so we
 405                  * have to tear down the connection and to inform all the
 406                  * other remaining servers in the network */
 407                 IRC_SendWallops(Client_ThisServer(), Client_ThisServer(),
 408                                 "Received SQUIT %s from %s: %s",
 409                                 Req->argv[0], Client_ID(from),
 410                                 Req->argv[1][0] ? Req->argv[1] : "-");
 411                 Conn_Close(con, NULL, msg, true);
 412                 if (con == Client_Conn(Client))
 413                         return DISCONNECTED;
 414         } else {
 415                 /* This server is not directly connected, so the SQUIT must
 416                  * be forwarded ... */
 417                 if (Client_Type(from) != CLIENT_SERVER) {
 418                         /* The origin is not an IRC server, so don't evaluate
 419                          * this SQUIT but simply forward it */
 420                         IRC_WriteStrClientPrefix(Client_NextHop(target),
 421                             from, "SQUIT %s :%s", Req->argv[0], Req->argv[1]);
 422                 } else {
 423                         /* SQUIT has been generated by another server, so
 424                          * remove the target server from the network! */
 425                         logmsg[0] = '\0';
 426                         if (!strchr(msg, '('))
 427                                 snprintf(logmsg, sizeof(logmsg),
 428                                          "\"%s\" (SQUIT from %s)", Req->argv[1],
 429                                          Client_ID(from));
 430                         Client_Destroy(target, logmsg[0] ? logmsg : msg,
 431                                        msg, false);
 432                 }
 433         }
 434         return CONNECTED;
 435 } /* IRC_SQUIT */
 436
 437 /* -eof- */