src/ngircd/irc-mode.c

   1 /*
   2  * ngIRCd -- The Next Generation IRC Daemon
   3  * Copyright (c)2001-2023 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 mode changes (like MODE, AWAY, etc.)
  17  */
  18
  19 #include <assert.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23
  24 #include "conn.h"
  25 #include "channel.h"
  26 #include "irc-macros.h"
  27 #include "irc-write.h"
  28 #include "lists.h"
  29 #include "log.h"
  30 #include "parse.h"
  31 #include "messages.h"
  32 #include "conf.h"
  33
  34 #include "irc-mode.h"
  35
  36 static bool Client_Mode PARAMS((CLIENT *Client, REQUEST *Req, CLIENT *Origin,
  37                                 CLIENT *Target));
  38 static bool Channel_Mode PARAMS((CLIENT *Client, REQUEST *Req, CLIENT *Origin,
  39                                  CHANNEL *Channel));
  40
  41 static bool Add_To_List PARAMS((char what, CLIENT *Prefix, CLIENT *Client,
  42                                 CHANNEL *Channel, const char *Pattern));
  43 static bool Del_From_List PARAMS((char what, CLIENT *Prefix, CLIENT *Client,
  44                                   CHANNEL *Channel, const char *Pattern));
  45
  46 static bool Send_ListChange PARAMS((const bool IsAdd, const char ModeChar,
  47                                     CLIENT *Prefix, CLIENT *Client,
  48                                     CHANNEL *Channel, const char *Mask));
  49
  50 /**
  51  * Handler for the IRC "MODE" command.
  52  *
  53  * This function detects whether user or channel modes should be modified
  54  * and calls the appropriate sub-functions.
  55  *
  56  * @param Client The client from which this command has been received.
  57  * @param Req Request structure with prefix and all parameters.
  58  * @return CONNECTED or DISCONNECTED.
  59  */
  60 GLOBAL bool
  61 IRC_MODE( CLIENT *Client, REQUEST *Req )
  62 {
  63         CLIENT *cl, *origin;
  64         CHANNEL *chan;
  65
  66         assert(Client != NULL);
  67         assert(Req != NULL);
  68
  69         _IRC_GET_SENDER_OR_RETURN_(origin, Req, Client)
  70
  71         /* Test for "fake" MODE commands injected by this local instance,
  72          * for example when handling the "DefaultUserModes" settings.
  73          * This doesn't harm real commands, because prefixes of regular
  74          * clients are checked in Validate_Prefix() and can't be faked. */
  75         if (Req->prefix && Client_Search(Req->prefix) == Client_ThisServer())
  76                 Client = Client_Search(Req->prefix);
  77
  78         /* Channel or user mode? */
  79         cl = NULL; chan = NULL;
  80         if (Client_IsValidNick(Req->argv[0]))
  81                 cl = Client_Search(Req->argv[0]);
  82         if (Channel_IsValidName(Req->argv[0]))
  83                 chan = Channel_Search(Req->argv[0]);
  84
  85         if (cl)
  86                 return Client_Mode(Client, Req, origin, cl);
  87         if (chan)
  88                 return Channel_Mode(Client, Req, origin, chan);
  89
  90         /* No target found! */
  91         return IRC_WriteErrClient(Client, ERR_NOSUCHNICK_MSG,
  92                         Client_ID(Client), Req->argv[0]);
  93 } /* IRC_MODE */
  94
  95 /**
  96  * Check if the "mode limit" for a client has been reached.
  97  *
  98  * This limit doesn't apply for servers or services!
  99  *
 100  * @param Client The client to check.
 101  * @param Count The number of modes already handled.
 102  * @return true if the limit has been reached.
 103  */
 104 static bool
 105 Mode_Limit_Reached(CLIENT *Client, int Count)
 106 {
 107         if (Client_Type(Client) == CLIENT_SERVER
 108             || Client_Type(Client) == CLIENT_SERVICE)
 109                 return false;
 110         if (Count < MAX_HNDL_MODES_ARG)
 111                 return false;
 112         return true;
 113 }
 114
 115 /**
 116  * Handle client mode requests
 117  *
 118  * @param Client The client from which this command has been received.
 119  * @param Req Request structure with prefix and all parameters.
 120  * @param Origin The originator of the MODE command (prefix).
 121  * @param Target The target (client) of this MODE command.
 122  * @return CONNECTED or DISCONNECTED.
 123  */
 124 static bool
 125 Client_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CLIENT *Target )
 126 {
 127         char the_modes[COMMAND_LEN], x[2], *mode_ptr;
 128         bool ok, set;
 129         bool send_RPL_HOSTHIDDEN_MSG = false;
 130         int mode_arg;
 131         size_t len;
 132
 133         /* Is the client allowed to request or change the modes? */
 134         if (Client_Type(Client) == CLIENT_USER) {
 135                 /* Users are only allowed to manipulate their own modes! */
 136                 if (Target != Client)
 137                         return IRC_WriteErrClient(Client,
 138                                                   ERR_USERSDONTMATCH_MSG,
 139                                                   Client_ID(Client));
 140         }
 141
 142         /* Mode request: let's answer it :-) */
 143         if (Req->argc == 1)
 144                 return IRC_WriteStrClient(Origin, RPL_UMODEIS_MSG,
 145                                           Client_ID(Target),
 146                                           Client_Modes(Target));
 147
 148         mode_arg = 1;
 149         mode_ptr = Req->argv[mode_arg];
 150
 151         /* Initial state: set or unset modes? */
 152         if (*mode_ptr == '+') {
 153                 set = true;
 154                 strcpy(the_modes, "+");
 155         } else if (*mode_ptr == '-') {
 156                 set = false;
 157                 strcpy(the_modes, "-");
 158         } else
 159                 return IRC_WriteErrClient(Origin, ERR_UMODEUNKNOWNFLAG_MSG,
 160                                           Client_ID(Origin));
 161
 162         x[1] = '\0';
 163         ok = CONNECTED;
 164         while (mode_ptr) {
 165                 mode_ptr++;
 166                 if (!*mode_ptr) {
 167                         /* Try next argument if there's any */
 168                         mode_arg++;
 169                         if (mode_arg < Req->argc)
 170                                 mode_ptr = Req->argv[mode_arg];
 171                         else
 172                                 break;
 173                 }
 174
 175                 switch(*mode_ptr) {
 176                   case '+':
 177                   case '-':
 178                         if ((*mode_ptr == '+' && !set)
 179                             || (*mode_ptr == '-' && set)) {
 180                                 /* Action modifier ("+"/"-") must be changed */
 181                                 len = strlen(the_modes) - 1;
 182                                 if (the_modes[len] == '+'
 183                                     || the_modes[len] == '-') {
 184                                         /* Last character in the "result
 185                                          * string" was an "action", so just
 186                                          * overwrite it with the new action */
 187                                         the_modes[len] = *mode_ptr;
 188                                 } else {
 189                                         /* Append new modifier character to
 190                                          * the resulting mode string */
 191                                         x[0] = *mode_ptr;
 192                                         strlcat(the_modes, x,
 193                                                 sizeof(the_modes));
 194                                 }
 195                                 if (*mode_ptr == '+')
 196                                         set = true;
 197                                 else
 198                                         set = false;
 199                         }
 200                         continue;
 201                 }
 202
 203                 /* Validate modes */
 204                 x[0] = '\0';
 205                 switch (*mode_ptr) {
 206                 case 'b': /* Block private msgs */
 207                 case 'C': /* Only messages from clients sharing a channel */
 208                 case 'i': /* Invisible */
 209                 case 'I': /* Hide channel list from WHOIS */
 210                 case 's': /* Server messages */
 211                 case 'w': /* Wallops messages */
 212                         x[0] = *mode_ptr;
 213                         break;
 214                 case 'a': /* Away */
 215                         if (Client_Type(Client) == CLIENT_SERVER) {
 216                                 x[0] = 'a';
 217                                 Client_SetAway(Origin, DEFAULT_AWAY_MSG);
 218                         } else
 219                                 ok = IRC_WriteErrClient(Origin,
 220                                                         ERR_NOPRIVILEGES_MSG,
 221                                                         Client_ID(Origin));
 222                         break;
 223                 case 'B': /* Bot */
 224                         if (Client_HasMode(Client, 'r'))
 225                                 ok = IRC_WriteErrClient(Origin,
 226                                                         ERR_RESTRICTED_MSG,
 227                                                         Client_ID(Origin));
 228                         else
 229                                 x[0] = 'B';
 230                         break;
 231                 case 'c': /* Receive connect notices */
 232                 case 'q': /* KICK-protected user */
 233                 case 'F': /* disable flood protection */
 234                           /* (only settable by IRC operators!) */
 235                         if (!set || Client_Type(Client) == CLIENT_SERVER
 236                             || Client_HasMode(Origin, 'o'))
 237                                 x[0] = *mode_ptr;
 238                         else
 239                                 ok = IRC_WriteErrClient(Origin,
 240                                                         ERR_NOPRIVILEGES_MSG,
 241                                                         Client_ID(Origin));
 242                         break;
 243                 case 'o': /* IRC operator (only unsettable!) */
 244                         if (!set || Client_Type(Client) == CLIENT_SERVER) {
 245                                 x[0] = 'o';
 246                         } else
 247                                 ok = IRC_WriteErrClient(Origin,
 248                                                         ERR_NOPRIVILEGES_MSG,
 249                                                         Client_ID(Origin));
 250                         break;
 251                 case 'r': /* Restricted (only settable) */
 252                         if (set || Client_Type(Client) == CLIENT_SERVER)
 253                                 x[0] = 'r';
 254                         else
 255                                 ok = IRC_WriteErrClient(Origin,
 256                                                         ERR_RESTRICTED_MSG,
 257                                                         Client_ID(Origin));
 258                         break;
 259                 case 'R': /* Registered (not [un]settable by clients) */
 260                         if (Client_Type(Client) == CLIENT_SERVER)
 261                                 x[0] = 'R';
 262                         else
 263                                 ok = IRC_WriteErrClient(Origin,
 264                                                         ERR_NICKREGISTER_MSG,
 265                                                         Client_ID(Origin));
 266                         break;
 267                 case 'x': /* Cloak hostname */
 268                         if (Client_HasMode(Client, 'r'))
 269                                 ok = IRC_WriteErrClient(Origin,
 270                                                         ERR_RESTRICTED_MSG,
 271                                                         Client_ID(Origin));
 272                         else if (!set || Conf_CloakHostModeX[0]
 273                                  || Client_Type(Client) == CLIENT_SERVER
 274                                  || Client_HasMode(Origin, 'o')) {
 275                                 x[0] = 'x';
 276                                 send_RPL_HOSTHIDDEN_MSG = true;
 277                         } else
 278                                 ok = IRC_WriteErrClient(Origin,
 279                                                         ERR_NOPRIVILEGES_MSG,
 280                                                         Client_ID(Origin));
 281                         break;
 282                 default:
 283                         if (Client_Type(Client) != CLIENT_SERVER) {
 284                                 LogDebug(
 285                                     "Unknown mode \"%c%c\" from \"%s\"!?",
 286                                     set ? '+' : '-', *mode_ptr,
 287                                     Client_ID(Origin));
 288                                 ok = IRC_WriteErrClient(Origin,
 289                                                         ERR_UMODEUNKNOWNFLAG2_MSG,
 290                                                         Client_ID(Origin),
 291                                                         set ? '+' : '-',
 292                                                         *mode_ptr);
 293                                 x[0] = '\0';
 294                         } else {
 295                                 LogDebug(
 296                                     "Handling unknown mode \"%c%c\" from \"%s\" for \"%s\" ...",
 297                                     set ? '+' : '-', *mode_ptr,
 298                                     Client_ID(Origin), Client_ID(Target));
 299                                 x[0] = *mode_ptr;
 300                         }
 301                 }
 302
 303                 if (!ok)
 304                         break;
 305
 306                 /* Is there a valid mode change? */
 307                 if (!x[0])
 308                         continue;
 309
 310                 if (set) {
 311                         if (Client_ModeAdd(Target, x[0]))
 312                                 strlcat(the_modes, x, sizeof(the_modes));
 313                 } else {
 314                         if (Client_ModeDel(Target, x[0]))
 315                                 strlcat(the_modes, x, sizeof(the_modes));
 316                 }
 317         }
 318
 319         /* Are there changed modes? */
 320         if (the_modes[1]) {
 321                 /* Remove needless action modifier characters */
 322                 len = strlen(the_modes) - 1;
 323                 if (the_modes[len] == '+' || the_modes[len] == '-')
 324                         the_modes[len] = '\0';
 325
 326                 if (Client_Type(Client) == CLIENT_SERVER) {
 327                         /* Forward modes to other servers */
 328                         if (Client_Conn(Target) != NONE) {
 329                                 /* Remote server (service?) changed modes
 330                                  * for one of our clients. Inform it! */
 331                                 IRC_WriteStrClientPrefix(Target, Origin,
 332                                                          "MODE %s :%s",
 333                                                          Client_ID(Target),
 334                                                          the_modes);
 335                         }
 336                         IRC_WriteStrServersPrefix(Client, Origin,
 337                                                   "MODE %s :%s",
 338                                                   Client_ID(Target),
 339                                                   the_modes);
 340                 } else {
 341                         /* Send reply to client and inform other servers */
 342                         ok = IRC_WriteStrClientPrefix(Client, Origin,
 343                                                       "MODE %s :%s",
 344                                                       Client_ID(Target),
 345                                                       the_modes);
 346                         IRC_WriteStrServersPrefix(Client, Origin,
 347                                                   "MODE %s :%s",
 348                                                   Client_ID(Target),
 349                                                   the_modes);
 350                 }
 351
 352                 if (send_RPL_HOSTHIDDEN_MSG && Client_Conn(Target) > NONE) {
 353                         /* A new (cloaked) hostname must be announced */
 354                         IRC_WriteStrClientPrefix(Target, Origin,
 355                                                  RPL_HOSTHIDDEN_MSG,
 356                                                  Client_ID(Target),
 357                                                  Client_HostnameDisplayed(Target));
 358
 359                 }
 360
 361                 LogDebug("%s \"%s\": Mode change, now \"%s\".",
 362                          Client_TypeText(Target), Client_Mask(Target),
 363                          Client_Modes(Target));
 364         }
 365
 366         return ok;
 367 } /* Client_Mode */
 368
 369 /*
 370  * Reply to a channel mode request.
 371  *
 372  * @param Origin The originator of the MODE command (prefix).
 373  * @param Channel The channel of which the modes should be sent.
 374  * @return CONNECTED or DISCONNECTED.
 375  */
 376 static bool
 377 Channel_Mode_Answer_Request(CLIENT *Origin, CHANNEL *Channel)
 378 {
 379         char the_modes[COMMAND_LEN], the_args[COMMAND_LEN], argadd[CLIENT_PASS_LEN];
 380         const char *mode_ptr;
 381
 382         if (!Channel_IsMemberOf(Channel, Origin)) {
 383                 /* Not a member: "simple" mode reply */
 384                 if (!IRC_WriteStrClient(Origin, RPL_CHANNELMODEIS_MSG,
 385                                         Client_ID(Origin), Channel_Name(Channel),
 386                                         Channel_Modes(Channel)))
 387                         return DISCONNECTED;
 388         } else {
 389                 /* The sender is a member: generate extended reply */
 390                 strlcpy(the_modes, Channel_Modes(Channel), sizeof(the_modes));
 391                 mode_ptr = the_modes;
 392                 the_args[0] = '\0';
 393
 394                 while(*mode_ptr) {
 395                         switch(*mode_ptr) {
 396                         case 'l':
 397                                 snprintf(argadd, sizeof(argadd), " %lu",
 398                                          Channel_MaxUsers(Channel));
 399                                 strlcat(the_args, argadd, sizeof(the_args));
 400                                 break;
 401                         case 'k':
 402                                 strlcat(the_args, " ", sizeof(the_args));
 403                                 strlcat(the_args, Channel_Key(Channel),
 404                                         sizeof(the_args));
 405                                 break;
 406                         }
 407                         mode_ptr++;
 408                 }
 409                 if (the_args[0])
 410                         strlcat(the_modes, the_args, sizeof(the_modes));
 411
 412                 if (!IRC_WriteStrClient(Origin, RPL_CHANNELMODEIS_MSG,
 413                                         Client_ID(Origin), Channel_Name(Channel),
 414                                         the_modes))
 415                         return DISCONNECTED;
 416         }
 417
 418 #ifndef STRICT_RFC
 419         /* Channel creation time */
 420         if (!IRC_WriteStrClient(Origin, RPL_CREATIONTIME_MSG,
 421                                   Client_ID(Origin), Channel_Name(Channel),
 422                                   Channel_CreationTime(Channel)))
 423                 return DISCONNECTED;
 424 #endif
 425         return CONNECTED;
 426 }
 427
 428 /**
 429  * Handle channel mode and channel-user mode changes
 430  *
 431  * @param Client The client from which this command has been received.
 432  * @param Req Request structure with prefix and all parameters.
 433  * @param Origin The originator of the MODE command (prefix).
 434  * @param Channel The target channel of this MODE command.
 435  * @return CONNECTED or DISCONNECTED.
 436  */
 437 static bool
 438 Channel_Mode(CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel)
 439 {
 440         char the_modes[COMMAND_LEN], the_args[COMMAND_LEN], x[2],
 441             argadd[CLIENT_PASS_LEN], *mode_ptr;
 442         bool connected, set, skiponce, retval, use_servermode,
 443              is_halfop, is_op, is_admin, is_owner, is_machine, is_oper;
 444         int mode_arg, arg_arg, mode_arg_count = 0;
 445         CLIENT *client;
 446         long l;
 447         size_t len;
 448
 449         is_halfop = is_op = is_admin = is_owner = is_machine = is_oper = false;
 450
 451         if (Channel_IsModeless(Channel))
 452                 return IRC_WriteErrClient(Client, ERR_NOCHANMODES_MSG,
 453                                 Client_ID(Client), Channel_Name(Channel));
 454
 455         /* Mode request: let's answer it :-) */
 456         if (Req->argc <= 1)
 457                 return Channel_Mode_Answer_Request(Origin, Channel);
 458
 459         /* Check if origin is oper and opers can use mode */
 460         use_servermode = Conf_OperServerMode;
 461         if(Client_HasMode(Client, 'o') && Conf_OperCanMode) {
 462                 is_oper = true;
 463         }
 464
 465         /* Check if client is a server/service */
 466         if(Client_Type(Client) == CLIENT_SERVER ||
 467            Client_Type(Client) == CLIENT_SERVICE) {
 468                 is_machine = true;
 469         }
 470
 471         /* Check if client is member of channel or an oper or an server/service */
 472         if(!Channel_IsMemberOf(Channel, Client) && !is_oper && !is_machine)
 473                 return IRC_WriteErrClient(Origin, ERR_NOTONCHANNEL_MSG,
 474                                           Client_ID(Origin),
 475                                           Channel_Name(Channel));
 476
 477         mode_arg = 1;
 478         mode_ptr = Req->argv[mode_arg];
 479         if (Req->argc > mode_arg + 1)
 480                 arg_arg = mode_arg + 1;
 481         else
 482                 arg_arg = -1;
 483
 484         /* Initial state: set or unset modes? */
 485         skiponce = false;
 486         switch (*mode_ptr) {
 487         case '-':
 488                 set = false;
 489                 break;
 490         case '+':
 491                 set = true;
 492                 break;
 493         default:
 494                 set = true;
 495                 skiponce = true;
 496         }
 497
 498         /* Prepare reply string */
 499         strcpy(the_modes, set ? "+" : "-");
 500         the_args[0] = '\0';
 501
 502         x[1] = '\0';
 503         connected = CONNECTED;
 504         while (mode_ptr) {
 505                 if (!skiponce)
 506                         mode_ptr++;
 507                 if (!*mode_ptr) {
 508                         /* Try next argument if there's any */
 509                         if (arg_arg < 0)
 510                                 break;
 511                         if (arg_arg > mode_arg)
 512                                 mode_arg = arg_arg;
 513                         else
 514                                 mode_arg++;
 515
 516                         if (mode_arg >= Req->argc)
 517                                 break;
 518                         mode_ptr = Req->argv[mode_arg];
 519
 520                         if (Req->argc > mode_arg + 1)
 521                                 arg_arg = mode_arg + 1;
 522                         else
 523                                 arg_arg = -1;
 524                 }
 525                 skiponce = false;
 526
 527                 switch (*mode_ptr) {
 528                 case '+':
 529                 case '-':
 530                         if (((*mode_ptr == '+') && !set)
 531                             || ((*mode_ptr == '-') && set)) {
 532                                 /* Action modifier ("+"/"-") must be changed ... */
 533                                 len = strlen(the_modes) - 1;
 534                                 if (the_modes[len] == '+' || the_modes[len] == '-') {
 535                                         /* Adjust last action modifier in result */
 536                                         the_modes[len] = *mode_ptr;
 537                                 } else {
 538                                         /* Append modifier character to result string */
 539                                         x[0] = *mode_ptr;
 540                                         strlcat(the_modes, x, sizeof(the_modes));
 541                                 }
 542                                 set = *mode_ptr == '+';
 543                         }
 544                         continue;
 545                 }
 546
 547                 /* Are there arguments left? */
 548                 if (arg_arg >= Req->argc)
 549                         arg_arg = -1;
 550
 551                 if(!is_machine && !is_oper) {
 552                         if (Channel_UserHasMode(Channel, Client, 'q'))
 553                                 is_owner = true;
 554                         if (Channel_UserHasMode(Channel, Client, 'a'))
 555                                 is_admin = true;
 556                         if (Channel_UserHasMode(Channel, Client, 'o'))
 557                                 is_op = true;
 558                         if (Channel_UserHasMode(Channel, Client, 'h'))
 559                                 is_halfop = true;
 560                 }
 561
 562                 /* Validate modes */
 563                 x[0] = '\0';
 564                 argadd[0] = '\0';
 565                 client = NULL;
 566                 switch (*mode_ptr) {
 567                 /* --- Channel modes --- */
 568                 case 'R': /* Registered users only */
 569                 case 's': /* Secret channel */
 570                 case 'z': /* Secure connections only */
 571                         if(!is_oper && !is_machine && !is_owner &&
 572                            !is_admin && !is_op) {
 573                                 connected = IRC_WriteErrClient(Origin,
 574                                         ERR_CHANOPRIVSNEEDED_MSG,
 575                                         Client_ID(Origin), Channel_Name(Channel));
 576                                 goto chan_exit;
 577                         }
 578                 case 'i': /* Invite only */
 579                 case 'V': /* Invite disallow */
 580                 case 'M': /* Only identified nicks can write */
 581                 case 'm': /* Moderated */
 582                 case 'n': /* Only members can write */
 583                 case 'N': /* Can't change nick while on this channel */
 584                 case 'Q': /* No kicks */
 585                 case 't': /* Topic locked */
 586                         if(is_oper || is_machine || is_owner ||
 587                            is_admin || is_op || is_halfop)
 588                                 x[0] = *mode_ptr;
 589                         else
 590                                 connected = IRC_WriteErrClient(Origin,
 591                                         ERR_CHANOPRIVSNEEDED_MSG,
 592                                         Client_ID(Origin), Channel_Name(Channel));
 593                         break;
 594                 case 'k': /* Channel key */
 595                         if (Mode_Limit_Reached(Client, mode_arg_count++))
 596                                 goto chan_exit;
 597                         if (!set) {
 598                                 if (is_oper || is_machine || is_owner ||
 599                                     is_admin || is_op || is_halfop) {
 600                                         x[0] = *mode_ptr;
 601                                         if (Channel_HasMode(Channel, 'k'))
 602                                                 strlcpy(argadd, "*", sizeof(argadd));
 603                                         if (arg_arg > mode_arg)
 604                                                 arg_arg++;
 605                                 } else
 606                                         connected = IRC_WriteErrClient(Origin,
 607                                                 ERR_CHANOPRIVSNEEDED_MSG,
 608                                                 Client_ID(Origin),
 609                                                 Channel_Name(Channel));
 610                                 break;
 611                         }
 612                         if (arg_arg <= mode_arg) {
 613                                 if (is_machine)
 614                                         Log(LOG_ERR,
 615                                             "Got MODE +k without key for \"%s\" from \"%s\"! Ignored.",
 616                                             Channel_Name(Channel), Client_ID(Origin));
 617                                 else
 618                                         connected = IRC_WriteErrClient(Origin,
 619                                                 ERR_NEEDMOREPARAMS_MSG,
 620                                                 Client_ID(Origin), Req->command);
 621                                 goto chan_exit;
 622                         }
 623                         if (!Req->argv[arg_arg][0] || strchr(Req->argv[arg_arg], ' ')) {
 624                                 if (is_machine)
 625                                         Log(LOG_ERR,
 626                                             "Got invalid key on MODE +k for \"%s\" from \"%s\"! Ignored.",
 627                                             Channel_Name(Channel), Client_ID(Origin));
 628                                 else
 629                                         connected = IRC_WriteErrClient(Origin,
 630                                                ERR_INVALIDMODEPARAM_MSG,
 631                                                 Client_ID(Origin),
 632                                                 Channel_Name(Channel), 'k');
 633                                 goto chan_exit;
 634                         }
 635                         if (is_oper || is_machine || is_owner ||
 636                             is_admin || is_op || is_halfop) {
 637                                 Channel_ModeDel(Channel, 'k');
 638                                 Channel_SetKey(Channel, Req->argv[arg_arg]);
 639                                 strlcpy(argadd, Channel_Key(Channel), sizeof(argadd));
 640                                 x[0] = *mode_ptr;
 641                         } else {
 642                                 connected = IRC_WriteErrClient(Origin,
 643                                         ERR_CHANOPRIVSNEEDED_MSG,
 644                                         Client_ID(Origin),
 645                                         Channel_Name(Channel));
 646                         }
 647                         Req->argv[arg_arg][0] = '\0';
 648                         arg_arg++;
 649                         break;
 650                 case 'l': /* Member limit */
 651                         if (Mode_Limit_Reached(Client, mode_arg_count++))
 652                                 goto chan_exit;
 653                         if (!set) {
 654                                 if (is_oper || is_machine || is_owner ||
 655                                     is_admin || is_op || is_halfop)
 656                                         x[0] = *mode_ptr;
 657                                 else
 658                                         connected = IRC_WriteErrClient(Origin,
 659                                                 ERR_CHANOPRIVSNEEDED_MSG,
 660                                                 Client_ID(Origin),
 661                                                 Channel_Name(Channel));
 662                                 break;
 663                         }
 664                         if (arg_arg <= mode_arg) {
 665                                 if (is_machine)
 666                                         Log(LOG_ERR,
 667                                             "Got MODE +l without limit for \"%s\" from \"%s\"! Ignored.",
 668                                             Channel_Name(Channel), Client_ID(Origin));
 669                                 else
 670                                         connected = IRC_WriteErrClient(Origin,
 671                                                 ERR_NEEDMOREPARAMS_MSG,
 672                                                 Client_ID(Origin), Req->command);
 673                                 goto chan_exit;
 674                         }
 675                         l = atol(Req->argv[arg_arg]);
 676                         if (l <= 0 || l >= 0xFFFF) {
 677                                 if (is_machine)
 678                                         Log(LOG_ERR,
 679                                             "Got MODE +l with invalid limit for \"%s\" from \"%s\"! Ignored.",
 680                                             Channel_Name(Channel), Client_ID(Origin));
 681                                 else
 682                                         connected = IRC_WriteErrClient(Origin,
 683                                                 ERR_INVALIDMODEPARAM_MSG,
 684                                                 Client_ID(Origin),
 685                                                 Channel_Name(Channel), 'l');
 686                                 goto chan_exit;
 687                         }
 688                         if (is_oper || is_machine || is_owner ||
 689                             is_admin || is_op || is_halfop) {
 690                                 Channel_ModeDel(Channel, 'l');
 691                                 Channel_SetMaxUsers(Channel, l);
 692                                 snprintf(argadd, sizeof(argadd), "%ld", l);
 693                                 x[0] = *mode_ptr;
 694                         } else {
 695                                 connected = IRC_WriteErrClient(Origin,
 696                                         ERR_CHANOPRIVSNEEDED_MSG,
 697                                         Client_ID(Origin),
 698                                         Channel_Name(Channel));
 699                         }
 700                         Req->argv[arg_arg][0] = '\0';
 701                         arg_arg++;
 702                         break;
 703                 case 'O': /* IRC operators only */
 704                         if (set) {
 705                                 /* Only IRC operators are allowed to
 706                                  * set the 'O' channel mode! */
 707                                 if(is_oper || is_machine)
 708                                         x[0] = 'O';
 709                                 else
 710                                         connected = IRC_WriteErrClient(Origin,
 711                                                 ERR_NOPRIVILEGES_MSG,
 712                                                 Client_ID(Origin));
 713                         } else if(is_oper || is_machine || is_owner ||
 714                                   is_admin || is_op)
 715                                 x[0] = 'O';
 716                         else
 717                                 connected = IRC_WriteErrClient(Origin,
 718                                         ERR_CHANOPRIVSNEEDED_MSG,
 719                                         Client_ID(Origin),
 720                                         Channel_Name(Channel));
 721                         break;
 722                 case 'P': /* Persistent channel */
 723                         if (set) {
 724                                 /* Only IRC operators are allowed to
 725                                  * set the 'P' channel mode! */
 726                                 if(is_oper || is_machine)
 727                                         x[0] = 'P';
 728                                 else
 729                                         connected = IRC_WriteErrClient(Origin,
 730                                                 ERR_NOPRIVILEGES_MSG,
 731                                                 Client_ID(Origin));
 732                         } else if(is_oper || is_machine || is_owner ||
 733                                   is_admin || is_op)
 734                                 x[0] = 'P';
 735                         else
 736                                 connected = IRC_WriteErrClient(Origin,
 737                                         ERR_CHANOPRIVSNEEDED_MSG,
 738                                         Client_ID(Origin),
 739                                         Channel_Name(Channel));
 740                         break;
 741                 /* --- Channel user modes --- */
 742                 case 'q': /* Owner */
 743                         if(!is_oper && !is_machine && !is_owner) {
 744                                 connected = IRC_WriteErrClient(Origin,
 745                                         ERR_CHANOPPRIVTOOLOW_MSG,
 746                                         Client_ID(Origin),
 747                                         Channel_Name(Channel));
 748                                 goto chan_exit;
 749                         }
 750                 case 'a': /* Channel admin */
 751                         if(!is_oper && !is_machine && !is_owner && !is_admin) {
 752                                 connected = IRC_WriteErrClient(Origin,
 753                                         ERR_CHANOPPRIVTOOLOW_MSG,
 754                                         Client_ID(Origin),
 755                                         Channel_Name(Channel));
 756                                 goto chan_exit;
 757                         }
 758                 case 'o': /* Channel operator */
 759                         if(!is_oper && !is_machine && !is_owner &&
 760                            !is_admin && !is_op) {
 761                                 connected = IRC_WriteErrClient(Origin,
 762                                         ERR_CHANOPRIVSNEEDED_MSG,
 763                                         Client_ID(Origin),
 764                                         Channel_Name(Channel));
 765                                 goto chan_exit;
 766                         }
 767                 case 'h': /* Half Op */
 768                         if(!is_oper && !is_machine && !is_owner &&
 769                            !is_admin && !is_op) {
 770                                 connected = IRC_WriteErrClient(Origin,
 771                                         ERR_CHANOPRIVSNEEDED_MSG,
 772                                         Client_ID(Origin),
 773                                         Channel_Name(Channel));
 774                                 goto chan_exit;
 775                         }
 776                 case 'v': /* Voice */
 777                         if (arg_arg > mode_arg) {
 778                                 if (is_oper || is_machine || is_owner ||
 779                                     is_admin || is_op || is_halfop) {
 780                                         client = Client_Search(Req->argv[arg_arg]);
 781                                         if (client)
 782                                                 x[0] = *mode_ptr;
 783                                         else
 784                                                 connected = IRC_WriteErrClient(Origin,
 785                                                         ERR_NOSUCHNICK_MSG,
 786                                                         Client_ID(Origin),
 787                                                         Req->argv[arg_arg]);
 788                                 } else {
 789                                         connected = IRC_WriteErrClient(Origin,
 790                                                 ERR_CHANOPRIVSNEEDED_MSG,
 791                                                 Client_ID(Origin),
 792                                                 Channel_Name(Channel));
 793                                 }
 794                                 Req->argv[arg_arg][0] = '\0';
 795                                 arg_arg++;
 796                         } else {
 797 #ifdef STRICT_RFC
 798                                 /* Report an error to the client, when a user
 799                                  * mode should be changed but no nickname is
 800                                  * given. But don't do it when not in "strict"
 801                                  * mode, because most other servers don't do
 802                                  * it as well and some clients send "wired"
 803                                  * MODE commands like "MODE #chan -ooo nick". */
 804                                 connected = IRC_WriteErrClient(Origin,
 805                                         ERR_NEEDMOREPARAMS_MSG,
 806                                         Client_ID(Origin), Req->command);
 807 #endif
 808                                 goto chan_exit;
 809                         }
 810                         break;
 811                 /* --- Channel lists --- */
 812                 case 'I': /* Invite lists */
 813                 case 'b': /* Ban lists */
 814                 case 'e': /* Channel exception lists */
 815                         if (Mode_Limit_Reached(Client, mode_arg_count++))
 816                                 goto chan_exit;
 817                         if (arg_arg > mode_arg) {
 818                                 /* modify list */
 819                                 if (is_oper || is_machine || is_owner ||
 820                                     is_admin || is_op || is_halfop) {
 821                                         connected = set
 822                                            ? Add_To_List(*mode_ptr, Origin,
 823                                                 Client, Channel,
 824                                                 Req->argv[arg_arg])
 825                                            : Del_From_List(*mode_ptr, Origin,
 826                                                 Client, Channel,
 827                                                 Req->argv[arg_arg]);
 828                                 } else {
 829                                         connected = IRC_WriteErrClient(Origin,
 830                                                 ERR_CHANOPRIVSNEEDED_MSG,
 831                                                 Client_ID(Origin),
 832                                                 Channel_Name(Channel));
 833                                 }
 834                                 Req->argv[arg_arg][0] = '\0';
 835                                 arg_arg++;
 836                         } else {
 837                                 switch (*mode_ptr) {
 838                                 case 'I':
 839                                         Channel_ShowInvites(Origin, Channel);
 840                                         break;
 841                                 case 'b':
 842                                         Channel_ShowBans(Origin, Channel);
 843                                         break;
 844                                 case 'e':
 845                                         Channel_ShowExcepts(Origin, Channel);
 846                                         break;
 847                                 }
 848                         }
 849                         break;
 850                 default:
 851                         if (Client_Type(Client) != CLIENT_SERVER) {
 852                                 LogDebug(
 853                                     "Unknown mode \"%c%c\" from \"%s\" on %s!?",
 854                                     set ? '+' : '-', *mode_ptr,
 855                                     Client_ID(Origin), Channel_Name(Channel));
 856                                 connected = IRC_WriteErrClient(Origin,
 857                                         ERR_UNKNOWNMODE_MSG,
 858                                         Client_ID(Origin), *mode_ptr,
 859                                         Channel_Name(Channel));
 860                                 x[0] = '\0';
 861                         } else {
 862                                 LogDebug(
 863                                     "Handling unknown mode \"%c%c\" from \"%s\" on %s ...",
 864                                     set ? '+' : '-', *mode_ptr,
 865                                     Client_ID(Origin), Channel_Name(Channel));
 866                                 x[0] = *mode_ptr;
 867                         }
 868                 }
 869
 870                 if (!connected)
 871                         break;
 872
 873                 /* Is there a valid mode change? */
 874                 if (!x[0])
 875                         continue;
 876
 877                 /* Validate target client */
 878                 if (client && (!Channel_IsMemberOf(Channel, client))) {
 879                         if (!IRC_WriteErrClient(Origin, ERR_USERNOTINCHANNEL_MSG,
 880                                                 Client_ID(Origin),
 881                                                 Client_ID(client),
 882                                                 Channel_Name(Channel)))
 883                                 break;
 884                         continue;
 885                 }
 886
 887                 if (client) {
 888                         /* Channel-User-Mode */
 889                         retval = set
 890                                ? Channel_UserModeAdd(Channel, client, x[0])
 891                                : Channel_UserModeDel(Channel, client, x[0]);
 892                         if (retval) {
 893                                 strlcat(the_args, " ", sizeof(the_args));
 894                                 strlcat(the_args, Client_ID(client),
 895                                         sizeof(the_args));
 896                                 strlcat(the_modes, x, sizeof(the_modes));
 897                                 LogDebug
 898                                     ("User \"%s\": Mode change on %s, now \"%s\"",
 899                                      Client_Mask(client), Channel_Name(Channel),
 900                                      Channel_UserModes(Channel, client));
 901                         }
 902                 } else {
 903                         /* Channel-Mode */
 904                         retval = set
 905                                ? Channel_ModeAdd(Channel, x[0])
 906                                : Channel_ModeDel(Channel, x[0]);
 907                         if (retval) {
 908                                 strlcat(the_modes, x, sizeof(the_modes));
 909                                 LogDebug("Channel %s: Mode change, now \"%s\".",
 910                                          Channel_Name(Channel),
 911                                          Channel_Modes(Channel));
 912                         }
 913                 }
 914
 915                 /* Are there additional arguments to add? */
 916                 if (argadd[0]) {
 917                         strlcat(the_args, " ", sizeof(the_args));
 918                         strlcat(the_args, argadd, sizeof(the_args));
 919                 }
 920         }
 921
 922       chan_exit:
 923         /* Are there changed modes? */
 924         if (the_modes[1]) {
 925                 /* Clean up mode string */
 926                 len = strlen(the_modes) - 1;
 927                 if ((the_modes[len] == '+') || (the_modes[len] == '-'))
 928                         the_modes[len] = '\0';
 929
 930                 if (Client_Type(Client) == CLIENT_SERVER) {
 931                         /* MODE requests for local channels from other servers
 932                          * are definitely invalid! */
 933                         if (Channel_IsLocal(Channel) && Client != Client_ThisServer()) {
 934                                 Log(LOG_ALERT, "Got remote MODE command for local channel!? Ignored.");
 935                                 return CONNECTED;
 936                         }
 937
 938                         /* Forward mode changes to channel users and all the
 939                          * other remote servers: */
 940                         IRC_WriteStrServersPrefix(Client, Origin,
 941                                 "MODE %s %s%s", Channel_Name(Channel),
 942                                 the_modes, the_args);
 943                         IRC_WriteStrChannelPrefix(Client, Channel, Origin,
 944                                 false, "MODE %s %s%s", Channel_Name(Channel),
 945                                 the_modes, the_args);
 946                 } else {
 947                         if (use_servermode)
 948                                 Origin = Client_ThisServer();
 949                         /* Send reply to client and inform other servers and channel users */
 950                         connected = IRC_WriteStrClientPrefix(Client, Origin,
 951                                         "MODE %s %s%s", Channel_Name(Channel),
 952                                         the_modes, the_args);
 953                         /* Only forward requests for non-local channels */
 954                         if (!Channel_IsLocal(Channel))
 955                                 IRC_WriteStrServersPrefix(Client, Origin,
 956                                         "MODE %s %s%s", Channel_Name(Channel),
 957                                         the_modes, the_args);
 958                         IRC_WriteStrChannelPrefix(Client, Channel, Origin,
 959                                 false, "MODE %s %s%s", Channel_Name(Channel),
 960                                 the_modes, the_args);
 961                 }
 962         }
 963
 964         return connected;
 965 } /* Channel_Mode */
 966
 967 /**
 968  * Handler for the IRC "AWAY" command.
 969  *
 970  * @param Client The client from which this command has been received.
 971  * @param Req Request structure with prefix and all parameters.
 972  * @return CONNECTED or DISCONNECTED.
 973  */
 974 GLOBAL bool
 975 IRC_AWAY( CLIENT *Client, REQUEST *Req )
 976 {
 977         assert (Client != NULL);
 978         assert (Req != NULL);
 979
 980         if (Req->argc == 1 && Req->argv[0][0]) {
 981                 Client_SetAway(Client, Req->argv[0]);
 982                 Client_ModeAdd(Client, 'a');
 983                 IRC_WriteStrServersPrefix(Client, Client, "MODE %s :+a",
 984                                           Client_ID( Client));
 985                 return IRC_WriteStrClient(Client, RPL_NOWAWAY_MSG,
 986                                           Client_ID( Client));
 987         } else {
 988                 Client_ModeDel(Client, 'a');
 989                 IRC_WriteStrServersPrefix(Client, Client, "MODE %s :-a",
 990                                           Client_ID( Client));
 991                 return IRC_WriteStrClient(Client, RPL_UNAWAY_MSG,
 992                                           Client_ID( Client));
 993         }
 994 } /* IRC_AWAY */
 995
 996 /**
 997  * Add entries to channel invite, ban and exception lists.
 998  *
 999  * @param what Can be 'I' for invite, 'b' for ban, and 'e' for exception list.
1000  * @param Prefix The originator of the command.
1001  * @param Client The sender of the command.
1002  * @param Channel The channel of which the list should be modified.
1003  * @param Pattern The pattern to add to the list.
1004  * @return CONNECTED or DISCONNECTED.
1005  */
1006 static bool
1007 Add_To_List(char what, CLIENT *Prefix, CLIENT *Client, CHANNEL *Channel,
1008             const char *Pattern)
1009 {
1010         char mask[MASK_LEN];
1011         struct list_head *list = NULL;
1012         long int current_count;
1013
1014         assert(Client != NULL);
1015         assert(Channel != NULL);
1016         assert(Pattern != NULL);
1017         assert(what == 'I' || what == 'b' || what == 'e');
1018
1019         Lists_MakeMask(Pattern, mask, sizeof(mask));
1020         current_count = Lists_Count(Channel_GetListInvites(Channel))
1021                         + Lists_Count(Channel_GetListExcepts(Channel))
1022                         + Lists_Count(Channel_GetListBans(Channel));
1023
1024         switch(what) {
1025                 case 'I':
1026                         list = Channel_GetListInvites(Channel);
1027                         break;
1028                 case 'b':
1029                         list = Channel_GetListBans(Channel);
1030                         break;
1031                 case 'e':
1032                         list = Channel_GetListExcepts(Channel);
1033                         break;
1034         }
1035
1036         if (Lists_CheckDupeMask(list, mask))
1037                 return CONNECTED;
1038         if (Client_Type(Client) == CLIENT_USER &&
1039             current_count >= MAX_HNDL_CHANNEL_LISTS)
1040                 return IRC_WriteErrClient(Client, ERR_LISTFULL_MSG,
1041                                           Client_ID(Client),
1042                                           Channel_Name(Channel), mask,
1043                                           MAX_HNDL_CHANNEL_LISTS);
1044
1045         switch (what) {
1046                 case 'I':
1047                         if (!Channel_AddInvite(Channel, mask, false, Client_ID(Client)))
1048                                 return CONNECTED;
1049                         break;
1050                 case 'b':
1051                         if (!Channel_AddBan(Channel, mask, Client_ID(Client)))
1052                                 return CONNECTED;
1053                         break;
1054                 case 'e':
1055                         if (!Channel_AddExcept(Channel, mask, Client_ID(Client)))
1056                                 return CONNECTED;
1057                         break;
1058         }
1059         return Send_ListChange(true, what, Prefix, Client, Channel, mask);
1060 }
1061
1062 /**
1063  * Delete entries from channel invite, ban and exception lists.
1064  *
1065  * @param what Can be 'I' for invite, 'b' for ban, and 'e' for exception list.
1066  * @param Prefix The originator of the command.
1067  * @param Client The sender of the command.
1068  * @param Channel The channel of which the list should be modified.
1069  * @param Pattern The pattern to add to the list.
1070  * @return CONNECTED or DISCONNECTED.
1071  */
1072 static bool
1073 Del_From_List(char what, CLIENT *Prefix, CLIENT *Client, CHANNEL *Channel,
1074               const char *Pattern)
1075 {
1076         char mask[MASK_LEN];
1077         struct list_head *list = NULL;
1078
1079         assert(Client != NULL);
1080         assert(Channel != NULL);
1081         assert(Pattern != NULL);
1082         assert(what == 'I' || what == 'b' || what == 'e');
1083
1084         Lists_MakeMask(Pattern, mask, sizeof(mask));
1085
1086         switch (what) {
1087                 case 'I':
1088                         list = Channel_GetListInvites(Channel);
1089                         break;
1090                 case 'b':
1091                         list = Channel_GetListBans(Channel);
1092                         break;
1093                 case 'e':
1094                         list = Channel_GetListExcepts(Channel);
1095                         break;
1096         }
1097
1098         if (!Lists_CheckDupeMask(list, mask))
1099                 return CONNECTED;
1100         Lists_Del(list, mask);
1101
1102         return Send_ListChange(false, what, Prefix, Client, Channel, mask);
1103 }
1104
1105 /**
1106  * Send information about changed channel invite/ban/exception lists to clients.
1107  *
1108  * @param IsAdd true if the list item has been added, false otherwise.
1109  * @param ModeChar The mode to use (e. g. 'b' or 'I')
1110  * @param Prefix The originator of the mode list change.
1111  * @param Client The sender of the command.
1112  * @param Channel The channel of which the list has been modified.
1113  * @param Mask The mask which has been added or removed.
1114  * @return CONNECTED or DISCONNECTED.
1115  */
1116 static bool
1117 Send_ListChange(const bool IsAdd, const char ModeChar, CLIENT *Prefix,
1118                 CLIENT *Client, CHANNEL *Channel, const char *Mask)
1119 {
1120         bool ok = true;
1121
1122         /* Send confirmation to the client */
1123         if (Client_Type(Client) == CLIENT_USER)
1124                 ok = IRC_WriteStrClientPrefix(Client, Prefix, "MODE %s %c%c %s",
1125                                               Channel_Name(Channel),
1126                                               IsAdd ? '+' : '-',
1127                                               ModeChar, Mask);
1128
1129         /* to other servers */
1130         IRC_WriteStrServersPrefix(Client, Prefix, "MODE %s %c%c %s",
1131                                   Channel_Name(Channel), IsAdd ? '+' : '-',
1132                                   ModeChar, Mask);
1133
1134         /* and local users in channel */
1135         IRC_WriteStrChannelPrefix(Client, Channel, Prefix, false,
1136                                   "MODE %s %c%c %s", Channel_Name(Channel),
1137                                   IsAdd ? '+' : '-', ModeChar, Mask );
1138
1139         return ok;
1140 } /* Send_ListChange */
1141
1142 /* -eof- */