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 #ifdef SSL_SUPPORT
 101                 /*
 102                  * This check is only done if RequireClientCert is disabled, and this Servers [SERVER] section has
 103                  * "SSLVerify" enabled.
 104                  * (if RequireClientCert is set, certificate validation is done during SSL/TLS handshake)
 105                  */
 106                 CONN_ID con = Client_Conn (Client);
 107                 if (Conf_Server[i].SSLVerify && !(Conn_Options(con) & CONN_SSL_PEERCERT_OK)) {
 108                         Log(LOG_ERR, "Connection %d: SSLVerify is set, and server \"%s\" did not present a valid certificate",
 109                                                                                 Client_Conn(Client), Req->argv[0]);
 110                         Conn_Close(Client_Conn(Client), NULL, "No valid SSL certificate", true);
 111                         return DISCONNECTED;
 112                 }
 113 #endif
 114
 115                 /* Is there a registered server with this ID? */
 116                 if (!Client_CheckID(Client, Req->argv[0]))
 117                         return DISCONNECTED;
 118
 119                 /* Mark this connection as belonging to an configured server */
 120                 if (!Conf_SetServer(i, Client_Conn(Client)))
 121                         return DISCONNECTED;
 122
 123                 Client_SetID( Client, Req->argv[0] );
 124                 Client_SetHops( Client, 1 );
 125                 Client_SetInfo( Client, Req->argv[Req->argc - 1] );
 126
 127                 /* Is this server registering on our side, or are we connecting to
 128                  * a remote server? */
 129                 if (Client_Token(Client) != TOKEN_OUTBOUND) {
 130                         /* Incoming connection, send user/pass */
 131                         if (!IRC_WriteStrClient(Client, "PASS %s %s",
 132                                                 Conf_Server[i].pwd_out,
 133                                                 NGIRCd_ProtoID)
 134                             || !IRC_WriteStrClient(Client, "SERVER %s 1 :%s",
 135                                                    Conf_ServerName,
 136                                                    Conf_ServerInfo)) {
 137                                     Conn_Close(Client_Conn(Client),
 138                                                "Unexpected server behavior!",
 139                                                NULL, false);
 140                                     return DISCONNECTED;
 141                         }
 142                         Client_SetIntroducer(Client, Client);
 143                         Client_SetToken(Client, 1);
 144                 } else {
 145                         /* outgoing connect, we already sent a SERVER and PASS
 146                          * command to the peer */
 147                         Client_SetToken(Client, atoi(Req->argv[1]));
 148                 }
 149
 150                 /* Check protocol level */
 151                 if (Client_Type(Client) == CLIENT_GOTPASS) {
 152                         /* We got a "simple" PASS command, so the peer is
 153                          * using the protocol as defined in RFC 1459. */
 154                         if (! (Conn_Options(Client_Conn(Client)) & CONN_RFC1459))
 155                                 Log(LOG_INFO,
 156                                     "Switching connection %d (\"%s\") to RFC 1459 compatibility mode.",
 157                                     Client_Conn(Client), Client_ID(Client));
 158                         Conn_SetOption(Client_Conn(Client), CONN_RFC1459);
 159                 }
 160
 161                 Client_SetType(Client, CLIENT_UNKNOWNSERVER);
 162
 163 #ifdef ZLIB
 164                 if (Client_HasFlag(Client, 'Z')
 165                     && !Zip_InitConn(Client_Conn(Client))) {
 166                         Conn_Close(Client_Conn(Client),
 167                                    "Can't initialize compression (zlib)!",
 168                                    NULL, false );
 169                         return DISCONNECTED;
 170                 }
 171 #endif
 172
 173 #ifdef IRCPLUS
 174                 if (Client_HasFlag(Client, 'H')) {
 175                         LogDebug("Peer supports IRC+ extended server handshake ...");
 176                         if (!IRC_Send_ISUPPORT(Client))
 177                                 return DISCONNECTED;
 178                         return IRC_WriteStrClient(Client, RPL_ENDOFMOTD_MSG,
 179                                                   Client_ID(Client));
 180                 } else {
 181 #endif
 182                         if (Conf_MaxNickLength != CLIENT_NICK_LEN_DEFAULT)
 183                                 Log(LOG_CRIT,
 184                                     "Attention: this server uses a non-standard nick length, but the peer doesn't support the IRC+ extended server handshake!");
 185 #ifdef IRCPLUS
 186                 }
 187 #endif
 188
 189                 return IRC_Num_ENDOFMOTD(Client, Req);
 190         }
 191         else if( Client_Type( Client ) == CLIENT_SERVER )
 192         {
 193                 /* New server is being introduced to the network */
 194
 195                 if (Req->argc != 4)
 196                         return IRC_WriteErrClient(Client, ERR_NEEDMOREPARAMS_MSG,
 197                                                   Client_ID(Client), Req->command);
 198
 199                 /* check for existing server with same ID */
 200                 if (!Client_CheckID(Client, Req->argv[0]))
 201                         return DISCONNECTED;
 202
 203                 from = Client_Search( Req->prefix );
 204                 if (! from) {
 205                         /* Uh, Server, that introduced the new server is unknown?! */
 206                         Log(LOG_ALERT,
 207                             "Unknown ID in prefix of SERVER: \"%s\"! (on connection %d)",
 208                             Req->prefix, Client_Conn(Client));
 209                         Conn_Close(Client_Conn(Client), NULL,
 210                                    "Unknown ID in prefix of SERVER", true);
 211                         return DISCONNECTED;
 212                 }
 213
 214                 c = Client_NewRemoteServer(Client, Req->argv[0], from,
 215                                            atoi(Req->argv[1]), atoi(Req->argv[2]),
 216                                            Req->argv[3], true);
 217                 if (!c) {
 218                         Log(LOG_ALERT,
 219                             "Can't create client structure for server! (on connection %d)",
 220                             Client_Conn(Client));
 221                         Conn_Close(Client_Conn(Client), NULL,
 222                                    "Can't allocate client structure for remote server",
 223                                    true);
 224                         return DISCONNECTED;
 225                 }
 226
 227                 if (Client_Hops(c) > 1 && Req->prefix[0])
 228                         snprintf(str, sizeof(str), "connected to %s, ",
 229                                  Client_ID(from));
 230                 else
 231                         strcpy(str, "");
 232                 Log(LOG_NOTICE|LOG_snotice,
 233                     "Server \"%s\" registered (via %s, %s%d hop%s).",
 234                     Client_ID(c), Client_ID(Client), str, Client_Hops(c),
 235                     Client_Hops(c) > 1 ? "s": "" );
 236
 237                 /* notify other servers */
 238                 IRC_WriteStrServersPrefix(Client, from, "SERVER %s %d %d :%s",
 239                                           Client_ID(c), Client_Hops(c) + 1,
 240                                           Client_MyToken(c), Client_Info(c));
 241
 242                 return CONNECTED;
 243         } else
 244                 return IRC_WriteErrClient(Client, ERR_NEEDMOREPARAMS_MSG,
 245                                           Client_ID(Client), Req->command);
 246 } /* IRC_SERVER */
 247
 248 /*
 249  * Handler for the IRC "NJOIN" command.
 250  *
 251  * @param Client The client from which this command has been received.
 252  * @param Req Request structure with prefix and all parameters.
 253  * @return CONNECTED or DISCONNECTED.
 254  */
 255 GLOBAL bool
 256 IRC_NJOIN( CLIENT *Client, REQUEST *Req )
 257 {
 258         char nick_in[COMMAND_LEN], nick_out[COMMAND_LEN], *channame, *ptr, modes[8];
 259         bool is_owner, is_chanadmin, is_op, is_halfop, is_voiced;
 260         CHANNEL *chan;
 261         CLIENT *c;
 262
 263         assert( Client != NULL );
 264         assert( Req != NULL );
 265
 266         strlcpy( nick_in, Req->argv[1], sizeof( nick_in ));
 267         strcpy( nick_out, "" );
 268
 269         channame = Req->argv[0];
 270         ptr = strtok( nick_in, "," );
 271         while( ptr )
 272         {
 273                 is_owner = is_chanadmin = is_op = is_halfop = is_voiced = false;
 274
 275                 /* cut off prefixes */
 276                 while(( *ptr == '~') || ( *ptr == '&' ) || ( *ptr == '@' ) ||
 277                         ( *ptr == '%') || ( *ptr == '+' ))
 278                 {
 279                         if( *ptr == '~' ) is_owner = true;
 280                         if( *ptr == '&' ) is_chanadmin = true;
 281                         if( *ptr == '@' ) is_op = true;
 282                         if( *ptr == 'h' ) is_halfop = true;
 283                         if( *ptr == '+' ) is_voiced = true;
 284                         ptr++;
 285                 }
 286
 287                 c = Client_Search( ptr );
 288                 if( c )
 289                 {
 290                         Channel_Join( c, channame );
 291                         chan = Channel_Search( channame );
 292                         assert( chan != NULL );
 293
 294                         if( is_owner ) Channel_UserModeAdd( chan, c, 'q' );
 295                         if( is_chanadmin ) Channel_UserModeAdd( chan, c, 'a' );
 296                         if( is_op ) Channel_UserModeAdd( chan, c, 'o' );
 297                         if( is_halfop ) Channel_UserModeAdd( chan, c, 'h' );
 298                         if( is_voiced ) Channel_UserModeAdd( chan, c, 'v' );
 299
 300                         /* announce to channel... */
 301                         IRC_WriteStrChannelPrefix( Client, chan, c, false, "JOIN :%s", channame );
 302
 303                         /* set Channel-User-Modes */
 304                         strlcpy( modes, Channel_UserModes( chan, c ), sizeof( modes ));
 305                         if( modes[0] )
 306                         {
 307                                 /* send modes to channel */
 308                                 IRC_WriteStrChannelPrefix( Client, chan, Client, false, "MODE %s +%s %s", channame, modes, Client_ID( c ));
 309                         }
 310
 311                         if( nick_out[0] != '\0' ) strlcat( nick_out, ",", sizeof( nick_out ));
 312                         if( is_owner ) strlcat( nick_out, "~", sizeof( nick_out ));
 313                         if( is_chanadmin ) strlcat( nick_out, "&", sizeof( nick_out ));
 314                         if( is_op ) strlcat( nick_out, "@", sizeof( nick_out ));
 315                         if( is_halfop ) strlcat( nick_out, "%", sizeof( nick_out ));
 316                         if( is_voiced ) strlcat( nick_out, "+", sizeof( nick_out ));
 317                         strlcat( nick_out, ptr, sizeof( nick_out ));
 318                 }
 319                 else Log( LOG_ERR, "Got NJOIN for unknown nick \"%s\" for channel \"%s\"!", ptr, channame );
 320
 321                 /* search for next Nick */
 322                 ptr = strtok( NULL, "," );
 323         }
 324
 325         /* forward to other servers */
 326         if (nick_out[0] != '\0')
 327                 IRC_WriteStrServersPrefix(Client, Client_ThisServer(),
 328                                           "NJOIN %s :%s", Req->argv[0], nick_out);
 329
 330         return CONNECTED;
 331 } /* IRC_NJOIN */
 332
 333 /**
 334  * Handler for the IRC "SQUIT" command.
 335  *
 336  * @param Client The client from which this command has been received.
 337  * @param Req Request structure with prefix and all parameters.
 338  * @return CONNECTED or DISCONNECTED.
 339  */
 340 GLOBAL bool
 341 IRC_SQUIT(CLIENT * Client, REQUEST * Req)
 342 {
 343         char msg[COMMAND_LEN], logmsg[COMMAND_LEN];
 344         CLIENT *from, *target;
 345         CONN_ID con;
 346         int loglevel;
 347
 348         assert(Client != NULL);
 349         assert(Req != NULL);
 350
 351         if (Client_Type(Client) != CLIENT_SERVER
 352             && !Client_HasMode(Client, 'o'))
 353                 return Op_NoPrivileges(Client, Req);
 354
 355         if (Client_Type(Client) == CLIENT_SERVER && Req->prefix) {
 356                 from = Client_Search(Req->prefix);
 357                 if (Client_Type(from) != CLIENT_SERVER
 358                     && !Op_Check(Client, Req))
 359                         return Op_NoPrivileges(Client, Req);
 360         } else
 361                 from = Client;
 362         if (!from)
 363                 return IRC_WriteErrClient(Client, ERR_NOSUCHNICK_MSG,
 364                                           Client_ID(Client), Req->prefix);
 365
 366         if (Client_Type(Client) == CLIENT_USER)
 367                 loglevel = LOG_NOTICE | LOG_snotice;
 368         else
 369                 loglevel = LOG_DEBUG;
 370         Log(loglevel, "Got SQUIT from %s for \"%s\": \"%s\" ...",
 371             Client_ID(from), Req->argv[0], Req->argv[1]);
 372
 373         target = Client_Search(Req->argv[0]);
 374         if (Client_Type(Client) != CLIENT_SERVER &&
 375             target == Client_ThisServer())
 376                 return Op_NoPrivileges(Client, Req);
 377         if (!target) {
 378                 /* The server is (already) unknown */
 379                 Log(LOG_WARNING,
 380                     "Got SQUIT from %s for unknown server \"%s\"!?",
 381                     Client_ID(Client), Req->argv[0]);
 382                 return CONNECTED;
 383         }
 384
 385         con = Client_Conn(target);
 386
 387         if (Req->argv[1][0])
 388                 if (Client_NextHop(from) != Client || con > NONE)
 389                         snprintf(msg, sizeof(msg), "\"%s\" (SQUIT from %s)",
 390                                  Req->argv[1], Client_ID(from));
 391                 else
 392                         strlcpy(msg, Req->argv[1], sizeof(msg));
 393         else
 394                 snprintf(msg, sizeof(msg), "Got SQUIT from %s",
 395                          Client_ID(from));
 396
 397         if (con > NONE) {
 398                 /* We are directly connected to the target server, so we
 399                  * have to tear down the connection and to inform all the
 400                  * other remaining servers in the network */
 401                 IRC_SendWallops(Client_ThisServer(), Client_ThisServer(),
 402                                 "Received SQUIT %s from %s: %s",
 403                                 Req->argv[0], Client_ID(from),
 404                                 Req->argv[1][0] ? Req->argv[1] : "-");
 405                 Conn_Close(con, NULL, msg, true);
 406                 if (con == Client_Conn(Client))
 407                         return DISCONNECTED;
 408         } else {
 409                 /* This server is not directly connected, so the SQUIT must
 410                  * be forwarded ... */
 411                 if (Client_Type(from) != CLIENT_SERVER) {
 412                         /* The origin is not an IRC server, so don't evaluate
 413                          * this SQUIT but simply forward it */
 414                         IRC_WriteStrClientPrefix(Client_NextHop(target),
 415                             from, "SQUIT %s :%s", Req->argv[0], Req->argv[1]);
 416                 } else {
 417                         /* SQUIT has been generated by another server, so
 418                          * remove the target server from the network! */
 419                         logmsg[0] = '\0';
 420                         if (!strchr(msg, '('))
 421                                 snprintf(logmsg, sizeof(logmsg),
 422                                          "\"%s\" (SQUIT from %s)", Req->argv[1],
 423                                          Client_ID(from));
 424                         Client_Destroy(target, logmsg[0] ? logmsg : msg,
 425                                        msg, false);
 426                 }
 427         }
 428         return CONNECTED;
 429 } /* IRC_SQUIT */
 430
 431 /* -eof- */