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.h"
  35 #include "irc-info.h"
  36 #include "irc-write.h"
  37 #include "op.h"
  38
  39 #include "irc-server.h"
  40
  41 /**
  42  * Handler for the IRC "SERVER" command.
  43  *
  44  * @param Client The client from which this command has been received.
  45  * @param Req Request structure with prefix and all parameters.
  46  * @return CONNECTED or DISCONNECTED.
  47  */
  48 GLOBAL bool
  49 IRC_SERVER( CLIENT *Client, REQUEST *Req )
  50 {
  51         char str[100];
  52         CLIENT *from, *c;
  53         int i;
  54
  55         assert( Client != NULL );
  56         assert( Req != NULL );
  57
  58         /* Return an error if this is not a local client */
  59         if (Client_Conn(Client) <= NONE)
  60                 return IRC_WriteErrClient(Client, ERR_UNKNOWNCOMMAND_MSG,
  61                                           Client_ID(Client), Req->command);
  62
  63         if (Client_Type(Client) == CLIENT_GOTPASS ||
  64             Client_Type(Client) == CLIENT_GOTPASS_2813) {
  65                 /* We got a PASS command from the peer, and now a SERVER
  66                  * command: the peer tries to register itself as a server. */
  67                 LogDebug("Connection %d: got SERVER command (new server link) ...",
  68                         Client_Conn(Client));
  69
  70                 if (Req->argc != 2 && Req->argc != 3)
  71                         return IRC_WriteErrClient(Client, ERR_NEEDMOREPARAMS_MSG,
  72                                                   Client_ID(Client),
  73                                                   Req->command);
  74
  75                 /* Get configuration index of new remote server ... */
  76                 for (i = 0; i < MAX_SERVERS; i++)
  77                         if (strcasecmp(Req->argv[0], Conf_Server[i].name) == 0)
  78                                 break;
  79
  80                 /* Make sure the remote server is configured here */
  81                 if (i >= MAX_SERVERS) {
  82                         Log(LOG_ERR,
  83                             "Connection %d: Server \"%s\" not configured here!",
  84                             Client_Conn(Client), Req->argv[0]);
  85                         Conn_Close(Client_Conn(Client), NULL,
  86                                    "Server not configured here", true);
  87                         return DISCONNECTED;
  88                 }
  89
  90                 /* Check server password */
  91                 if (strcmp(Conn_Password(Client_Conn(Client)),
  92                     Conf_Server[i].pwd_in) != 0) {
  93                         Log(LOG_ERR,
  94                             "Connection %d: Got bad password from server \"%s\"!",
  95                             Client_Conn(Client), Req->argv[0]);
  96                         Conn_Close(Client_Conn(Client), NULL,
  97                                    "Bad password", true);
  98                         return DISCONNECTED;
  99                 }
 100
 101                 /* Is there a registered server with this ID? */
 102                 if (!Client_CheckID(Client, Req->argv[0]))
 103                         return DISCONNECTED;
 104
 105                 /* Mark this connection as belonging to an configured server */
 106                 if (!Conf_SetServer(i, Client_Conn(Client)))
 107                         return DISCONNECTED;
 108
 109                 Client_SetID( Client, Req->argv[0] );
 110                 Client_SetHops( Client, 1 );
 111                 Client_SetInfo( Client, Req->argv[Req->argc - 1] );
 112
 113                 /* Is this server registering on our side, or are we connecting to
 114                  * a remote server? */
 115                 if (Client_Token(Client) != TOKEN_OUTBOUND) {
 116                         /* Incoming connection, send user/pass */
 117                         if (!IRC_WriteStrClient(Client, "PASS %s %s",
 118                                                 Conf_Server[i].pwd_out,
 119                                                 NGIRCd_ProtoID)
 120                             || !IRC_WriteStrClient(Client, "SERVER %s 1 :%s",
 121                                                    Conf_ServerName,
 122                                                    Conf_ServerInfo)) {
 123                                     Conn_Close(Client_Conn(Client),
 124                                                "Unexpected server behavior!",
 125                                                NULL, false);
 126                                     return DISCONNECTED;
 127                         }
 128                         Client_SetIntroducer(Client, Client);
 129                         Client_SetToken(Client, 1);
 130                 } else {
 131                         /* outgoing connect, we already sent a SERVER and PASS
 132                          * command to the peer */
 133                         Client_SetToken(Client, atoi(Req->argv[1]));
 134                 }
 135
 136                 /* Check protocol level */
 137                 if (Client_Type(Client) == CLIENT_GOTPASS) {
 138                         /* We got a "simple" PASS command, so the peer is
 139                          * using the protocol as defined in RFC 1459. */
 140                         if (! (Conn_Options(Client_Conn(Client)) & CONN_RFC1459))
 141                                 Log(LOG_INFO,
 142                                     "Switching connection %d (\"%s\") to RFC 1459 compatibility mode.",
 143                                     Client_Conn(Client), Client_ID(Client));
 144                         Conn_SetOption(Client_Conn(Client), CONN_RFC1459);
 145                 }
 146
 147                 Client_SetType(Client, CLIENT_UNKNOWNSERVER);
 148
 149 #ifdef ZLIB
 150                 if (Client_HasFlag(Client, 'Z')
 151                     && !Zip_InitConn(Client_Conn(Client))) {
 152                         Conn_Close(Client_Conn(Client),
 153                                    "Can't initialize compression (zlib)!",
 154                                    NULL, false );
 155                         return DISCONNECTED;
 156                 }
 157 #endif
 158
 159 #ifdef IRCPLUS
 160                 if (Client_HasFlag(Client, 'H')) {
 161                         LogDebug("Peer supports IRC+ extended server handshake ...");
 162                         if (!IRC_Send_ISUPPORT(Client))
 163                                 return DISCONNECTED;
 164                         return IRC_WriteStrClient(Client, RPL_ENDOFMOTD_MSG,
 165                                                   Client_ID(Client));
 166                 } else {
 167 #endif
 168                         if (Conf_MaxNickLength != CLIENT_NICK_LEN_DEFAULT)
 169                                 Log(LOG_CRIT,
 170                                     "Attention: this server uses a non-standard nick length, but the peer doesn't support the IRC+ extended server handshake!");
 171 #ifdef IRCPLUS
 172                 }
 173 #endif
 174
 175                 return IRC_Num_ENDOFMOTD(Client, Req);
 176         }
 177         else if( Client_Type( Client ) == CLIENT_SERVER )
 178         {
 179                 /* New server is being introduced to the network */
 180
 181                 if (Req->argc != 4)
 182                         return IRC_WriteErrClient(Client, ERR_NEEDMOREPARAMS_MSG,
 183                                                   Client_ID(Client), Req->command);
 184
 185                 /* check for existing server with same ID */
 186                 if (!Client_CheckID(Client, Req->argv[0]))
 187                         return DISCONNECTED;
 188
 189                 if (!Req->prefix) {
 190                         /* We definitely need a prefix here! */
 191                         Log(LOG_ALERT, "Got SERVER command without prefix! (on connection %d)",
 192                             Client_Conn(Client));
 193                         Conn_Close(Client_Conn(Client), NULL,
 194                                    "SERVER command without prefix", true);
 195                         return DISCONNECTED;
 196                 }
 197
 198                 from = Client_Search( Req->prefix );
 199                 if (! from) {
 200                         /* Uh, Server, that introduced the new server is unknown?! */
 201                         Log(LOG_ALERT,
 202                             "Unknown ID in prefix of SERVER: \"%s\"! (on connection %d)",
 203                             Req->prefix, Client_Conn(Client));
 204                         Conn_Close(Client_Conn(Client), NULL,
 205                                    "Unknown ID in prefix of SERVER", true);
 206                         return DISCONNECTED;
 207                 }
 208
 209                 c = Client_NewRemoteServer(Client, Req->argv[0], from,
 210                                            atoi(Req->argv[1]), atoi(Req->argv[2]),
 211                                            Req->argv[3], true);
 212                 if (!c) {
 213                         Log(LOG_ALERT,
 214                             "Can't create client structure for server! (on connection %d)",
 215                             Client_Conn(Client));
 216                         Conn_Close(Client_Conn(Client), NULL,
 217                                    "Can't allocate client structure for remote server",
 218                                    true);
 219                         return DISCONNECTED;
 220                 }
 221
 222                 if (Client_Hops(c) > 1 && Req->prefix[0])
 223                         snprintf(str, sizeof(str), "connected to %s, ",
 224                                  Client_ID(from));
 225                 else
 226                         strcpy(str, "");
 227                 Log(LOG_NOTICE|LOG_snotice,
 228                     "Server \"%s\" registered (via %s, %s%d hop%s).",
 229                     Client_ID(c), Client_ID(Client), str, Client_Hops(c),
 230                     Client_Hops(c) > 1 ? "s": "" );
 231
 232                 /* notify other servers */
 233                 IRC_WriteStrServersPrefix(Client, from, "SERVER %s %d %d :%s",
 234                                           Client_ID(c), Client_Hops(c) + 1,
 235                                           Client_MyToken(c), Client_Info(c));
 236
 237                 return CONNECTED;
 238         } else
 239                 return IRC_WriteErrClient(Client, ERR_NEEDMOREPARAMS_MSG,
 240                                           Client_ID(Client), Req->command);
 241 } /* IRC_SERVER */
 242
 243 /*
 244  * Handler for the IRC "NJOIN" command.
 245  *
 246  * @param Client The client from which this command has been received.
 247  * @param Req Request structure with prefix and all parameters.
 248  * @return CONNECTED or DISCONNECTED.
 249  */
 250 GLOBAL bool
 251 IRC_NJOIN( CLIENT *Client, REQUEST *Req )
 252 {
 253         char nick_in[COMMAND_LEN], nick_out[COMMAND_LEN], *channame, *ptr, modes[8];
 254         bool is_owner, is_chanadmin, is_op, is_halfop, is_voiced;
 255         CHANNEL *chan;
 256         CLIENT *c;
 257
 258         assert(Client != NULL);
 259         assert(Req != NULL);
 260
 261         strlcpy(nick_in, Req->argv[1], sizeof(nick_in));
 262         strcpy(nick_out, "");
 263
 264         channame = Req->argv[0];
 265
 266         ptr = strtok(nick_in, ",");
 267         while (ptr) {
 268                 is_owner = is_chanadmin = is_op = is_halfop = is_voiced = false;
 269
 270                 /* cut off prefixes */
 271                 while ((*ptr == '~') || (*ptr == '&') || (*ptr == '@') ||
 272                        (*ptr == '%') || (*ptr == '+')) {
 273                         if (*ptr == '~')
 274                                 is_owner = true;
 275                         if (*ptr == '&')
 276                                 is_chanadmin = true;
 277                         if (*ptr == '@')
 278                                 is_op = true;
 279                         if (*ptr == '%')
 280                                 is_halfop = true;
 281                         if (*ptr == '+')
 282                                 is_voiced = true;
 283                         ptr++;
 284                 }
 285
 286                 c = Client_Search(ptr);
 287                 if (!c) {
 288                         /* Client not found? */
 289                         Log(LOG_ERR,
 290                             "Got NJOIN for unknown nick \"%s\" for channel \"%s\"!",
 291                             ptr, channame);
 292                         goto skip_njoin;
 293                 }
 294
 295                 if (!Channel_Join(c, channame)) {
 296                         /* Failed to join channel. Ooops!? */
 297                         Log(LOG_ALERT,
 298                             "Failed to join client \"%s\" to channel \"%s\" (NJOIN): killing it!",
 299                             ptr, channame);
 300                         IRC_KillClient(NULL, NULL, ptr, "Internal NJOIN error!");
 301                         LogDebug("... done.");
 302                         goto skip_njoin;
 303                 }
 304
 305                 chan = Channel_Search(channame);
 306                 assert(chan != NULL);
 307
 308                 if (is_owner)
 309                         Channel_UserModeAdd(chan, c, 'q');
 310                 if (is_chanadmin)
 311                         Channel_UserModeAdd(chan, c, 'a');
 312                 if (is_op)
 313                         Channel_UserModeAdd(chan, c, 'o');
 314                 if (is_halfop)
 315                         Channel_UserModeAdd(chan, c, 'h');
 316                 if (is_voiced)
 317                         Channel_UserModeAdd(chan, c, 'v');
 318
 319                 /* Announce client to the channel */
 320                 IRC_WriteStrChannelPrefix(Client, chan, c, false,
 321                                           "JOIN :%s", channame);
 322
 323                 /* Announce "channel user modes" to the channel, if any */
 324                 strlcpy(modes, Channel_UserModes(chan, c), sizeof(modes));
 325                 if (modes[0])
 326                         IRC_WriteStrChannelPrefix(Client, chan, Client, false,
 327                                                   "MODE %s +%s %s", channame,
 328                                                   modes, Client_ID(c));
 329
 330                 /* Build nick list for forwarding command */
 331                 if (nick_out[0] != '\0')
 332                         strlcat(nick_out, ",", sizeof(nick_out));
 333                 if (is_owner)
 334                         strlcat(nick_out, "~", sizeof(nick_out));
 335                 if (is_chanadmin)
 336                         strlcat(nick_out, "&", sizeof(nick_out));
 337                 if (is_op)
 338                         strlcat(nick_out, "@", sizeof(nick_out));
 339                 if (is_halfop)
 340                         strlcat(nick_out, "%", sizeof(nick_out));
 341                 if (is_voiced)
 342                         strlcat(nick_out, "+", sizeof(nick_out));
 343                 strlcat(nick_out, ptr, sizeof(nick_out));
 344
 345               skip_njoin:
 346                 /* Get next nick, if any ... */
 347                 ptr = strtok(NULL, ",");
 348         }
 349
 350         /* forward to other servers */
 351         if (nick_out[0] != '\0')
 352                 IRC_WriteStrServersPrefix(Client, Client_ThisServer(),
 353                                           "NJOIN %s :%s", Req->argv[0], nick_out);
 354
 355         return CONNECTED;
 356 } /* IRC_NJOIN */
 357
 358 /**
 359  * Handler for the IRC "SQUIT" command.
 360  *
 361  * @param Client The client from which this command has been received.
 362  * @param Req Request structure with prefix and all parameters.
 363  * @return CONNECTED or DISCONNECTED.
 364  */
 365 GLOBAL bool
 366 IRC_SQUIT(CLIENT * Client, REQUEST * Req)
 367 {
 368         char msg[COMMAND_LEN], logmsg[COMMAND_LEN];
 369         CLIENT *from, *target;
 370         CONN_ID con, client_con;
 371         int loglevel;
 372
 373         assert(Client != NULL);
 374         assert(Req != NULL);
 375
 376         if (Client_Type(Client) != CLIENT_SERVER
 377             && !Client_HasMode(Client, 'o'))
 378                 return Op_NoPrivileges(Client, Req);
 379
 380         if (Client_Type(Client) == CLIENT_SERVER && Req->prefix) {
 381                 from = Client_Search(Req->prefix);
 382                 if (Client_Type(from) != CLIENT_SERVER
 383                     && !Op_Check(Client, Req))
 384                         return Op_NoPrivileges(Client, Req);
 385         } else
 386                 from = Client;
 387         if (!from)
 388                 return IRC_WriteErrClient(Client, ERR_NOSUCHNICK_MSG,
 389                                           Client_ID(Client), Req->prefix);
 390
 391         if (Client_Type(Client) == CLIENT_USER)
 392                 loglevel = LOG_NOTICE | LOG_snotice;
 393         else
 394                 loglevel = LOG_DEBUG;
 395         Log(loglevel, "Got SQUIT from %s for \"%s\": \"%s\" ...",
 396             Client_ID(from), Req->argv[0], Req->argv[1]);
 397
 398         target = Client_Search(Req->argv[0]);
 399         if (Client_Type(Client) != CLIENT_SERVER &&
 400             target == Client_ThisServer())
 401                 return Op_NoPrivileges(Client, Req);
 402         if (!target) {
 403                 /* The server is (already) unknown */
 404                 Log(LOG_WARNING,
 405                     "Got SQUIT from %s for unknown server \"%s\"!?",
 406                     Client_ID(Client), Req->argv[0]);
 407                 return CONNECTED;
 408         }
 409
 410         client_con = Client_Conn(Client);
 411         con = Client_Conn(target);
 412
 413         if (Req->argv[1][0])
 414                 if (Client_NextHop(from) != Client || con > NONE)
 415                         snprintf(msg, sizeof(msg), "\"%s\" (SQUIT from %s)",
 416                                  Req->argv[1], Client_ID(from));
 417                 else
 418                         strlcpy(msg, Req->argv[1], sizeof(msg));
 419         else
 420                 snprintf(msg, sizeof(msg), "Got SQUIT from %s",
 421                          Client_ID(from));
 422
 423         if (con > NONE) {
 424                 /* We are directly connected to the target server, so we
 425                  * have to tear down the connection and to inform all the
 426                  * other remaining servers in the network */
 427                 IRC_SendWallops(Client_ThisServer(), Client_ThisServer(),
 428                                 "Received SQUIT %s from %s: %s",
 429                                 Req->argv[0], Client_ID(from),
 430                                 Req->argv[1][0] ? Req->argv[1] : "-");
 431                 Conn_Close(con, NULL, msg, true);
 432                 if (con == client_con)
 433                         return DISCONNECTED;
 434         } else {
 435                 /* This server is not directly connected, so the SQUIT must
 436                  * be forwarded ... */
 437                 if (Client_Type(from) != CLIENT_SERVER) {
 438                         /* The origin is not an IRC server, so don't evaluate
 439                          * this SQUIT but simply forward it */
 440                         IRC_WriteStrClientPrefix(Client_NextHop(target),
 441                             from, "SQUIT %s :%s", Req->argv[0], Req->argv[1]);
 442                 } else {
 443                         /* SQUIT has been generated by another server, so
 444                          * remove the target server from the network! */
 445                         logmsg[0] = '\0';
 446                         if (!strchr(msg, '('))
 447                                 snprintf(logmsg, sizeof(logmsg),
 448                                          "\"%s\" (SQUIT from %s)", Req->argv[1],
 449                                          Client_ID(from));
 450                         Client_Destroy(target, logmsg[0] ? logmsg : msg,
 451                                        msg, false);
 452                 }
 453         }
 454         return CONNECTED;
 455 } /* IRC_SQUIT */
 456
 457 /* -eof- */