src/ngircd/parse.c

   1 /*
   2  * ngIRCd -- The Next Generation IRC Daemon
   3  * Copyright (c)2001-2018 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 command parser and validator.
  17  */
  18
  19 #include <assert.h>
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <strings.h>
  23
  24 #include "ngircd.h"
  25 #include "conn-func.h"
  26 #include "conf.h"
  27 #include "channel.h"
  28 #include "log.h"
  29 #include "messages.h"
  30
  31 #include "parse.h"
  32
  33 #include "irc.h"
  34 #include "irc-cap.h"
  35 #include "irc-channel.h"
  36 #ifdef ICONV
  37 # include "irc-encoding.h"
  38 #endif
  39 #include "irc-info.h"
  40 #include "irc-login.h"
  41 #include "irc-metadata.h"
  42 #include "irc-mode.h"
  43 #include "irc-op.h"
  44 #include "irc-oper.h"
  45 #include "irc-server.h"
  46 #include "irc-write.h"
  47 #include "numeric.h"
  48
  49 struct _NUMERIC {
  50         int numeric;
  51         bool (*function) PARAMS(( CLIENT *Client, REQUEST *Request ));
  52 };
  53
  54
  55 static COMMAND My_Commands[] =
  56 {
  57 #define _CMD(name, func, type, min, max, penalty) \
  58     { (name), (func), (type), (min), (max), (penalty), 0, 0, 0 }
  59         _CMD("ADMIN", IRC_ADMIN, CLIENT_USER|CLIENT_SERVER, 0, 1, 1),
  60         _CMD("AWAY", IRC_AWAY, CLIENT_USER, 0, 1, 0),
  61         _CMD("CAP", IRC_CAP, CLIENT_ANY, 1, 2, 0),
  62         _CMD("CONNECT", IRC_CONNECT, CLIENT_USER|CLIENT_SERVER, 0, -1, 0),
  63 #ifdef STRICT_RFC
  64         _CMD("DIE", IRC_DIE, CLIENT_USER, 0, 0, 0),
  65 #else
  66         _CMD("DIE", IRC_DIE, CLIENT_USER, 0, 1, 0),
  67 #endif
  68         _CMD("DISCONNECT", IRC_DISCONNECT, CLIENT_USER, 1, 1, 0),
  69         _CMD("ERROR", IRC_ERROR, CLIENT_ANY, 0, -1, 0),
  70         _CMD("GLINE", IRC_xLINE, CLIENT_USER|CLIENT_SERVER, 0, -1, 0),
  71         _CMD("HELP", IRC_HELP, CLIENT_USER, 0, 1, 2),
  72         _CMD("INFO", IRC_INFO, CLIENT_USER|CLIENT_SERVER, 0, 1, 2),
  73         _CMD("INVITE", IRC_INVITE, CLIENT_USER|CLIENT_SERVER, 2, 2, 1),
  74         _CMD("ISON", IRC_ISON, CLIENT_USER, 1, -1, 0),
  75         _CMD("JOIN", IRC_JOIN, CLIENT_USER|CLIENT_SERVER, 1, 2, 0),
  76         _CMD("KICK", IRC_KICK, CLIENT_USER|CLIENT_SERVER, 2, 3, 0),
  77         _CMD("KILL", IRC_KILL, CLIENT_USER|CLIENT_SERVER, 2, 2, 0),
  78         _CMD("KLINE", IRC_xLINE, CLIENT_USER|CLIENT_SERVER, 0, -1, 0),
  79         _CMD("LINKS", IRC_LINKS, CLIENT_USER|CLIENT_SERVER, 0, 2, 1),
  80         _CMD("LIST", IRC_LIST, CLIENT_USER|CLIENT_SERVER, 0, 2, 2),
  81         _CMD("LUSERS", IRC_LUSERS, CLIENT_USER|CLIENT_SERVER, 0, 2, 1),
  82         _CMD("METADATA", IRC_METADATA, CLIENT_SERVER, 3, 3, 0),
  83         _CMD("MODE", IRC_MODE, CLIENT_USER|CLIENT_SERVER, 1, -1, 1),
  84         _CMD("MOTD", IRC_MOTD, CLIENT_USER|CLIENT_SERVER, 0, 1, 3),
  85         _CMD("NAMES", IRC_NAMES, CLIENT_USER|CLIENT_SERVER, 0, 2, 1),
  86         _CMD("NICK", IRC_NICK, CLIENT_ANY, 0, -1, 0),
  87         _CMD("NJOIN", IRC_NJOIN, CLIENT_SERVER, 2, 2, 0),
  88         _CMD("NOTICE", IRC_NOTICE, CLIENT_ANY, 0, -1, 0),
  89         _CMD("OPER", IRC_OPER, CLIENT_USER, 2, 2, 0),
  90         _CMD("PART", IRC_PART, CLIENT_USER|CLIENT_SERVER, 1, 2, 0),
  91         _CMD("PASS", IRC_PASS, CLIENT_ANY, 0, -1, 0),
  92         _CMD("PING", IRC_PING, CLIENT_USER|CLIENT_SERVER, 0, -1, 0),
  93         _CMD("PONG", IRC_PONG, CLIENT_ANY, 0, -1, 0),
  94         _CMD("PRIVMSG", IRC_PRIVMSG, CLIENT_USER|CLIENT_SERVER, 0, 2, 0),
  95         _CMD("QUIT", IRC_QUIT, CLIENT_ANY, 0, 1, 0),
  96         _CMD("REHASH", IRC_REHASH, CLIENT_USER, 0, 0, 0),
  97         _CMD("RESTART", IRC_RESTART, CLIENT_USER, 0, 0, 0),
  98         _CMD("SERVER", IRC_SERVER, CLIENT_ANY, 0, -1, 0),
  99         _CMD("SERVICE", IRC_SERVICE, CLIENT_ANY, 6, 6, 0),
 100         _CMD("SERVLIST", IRC_SERVLIST, CLIENT_USER, 0, 2, 1),
 101         _CMD("SQUERY", IRC_SQUERY, CLIENT_USER|CLIENT_SERVER, 0, 2, 0),
 102         _CMD("SQUIT", IRC_SQUIT, CLIENT_USER|CLIENT_SERVER, 2, 2, 0),
 103         _CMD("STATS", IRC_STATS, CLIENT_USER|CLIENT_SERVER, 0, 2, 2),
 104         _CMD("SVSNICK", IRC_SVSNICK, CLIENT_SERVER, 2, 2, 0),
 105         _CMD("SUMMON", IRC_SUMMON, CLIENT_USER|CLIENT_SERVER, 0, -1, 0),
 106         _CMD("TIME", IRC_TIME, CLIENT_USER|CLIENT_SERVER, 0, 1, 1),
 107         _CMD("TOPIC", IRC_TOPIC, CLIENT_USER|CLIENT_SERVER, 1, 2, 1),
 108         _CMD("TRACE", IRC_TRACE, CLIENT_USER|CLIENT_SERVER, 0, 1, 3),
 109         _CMD("USER", IRC_USER, CLIENT_ANY, 0, -1, 0),
 110         _CMD("USERHOST", IRC_USERHOST, CLIENT_USER, 1, -1, 1),
 111         _CMD("USERS", IRC_USERS, CLIENT_USER|CLIENT_SERVER, 0, -1, 0),
 112         _CMD("VERSION", IRC_VERSION, CLIENT_USER|CLIENT_SERVER, 0, 1, 1),
 113         _CMD("WALLOPS", IRC_WALLOPS, CLIENT_USER|CLIENT_SERVER, 1, 1, 0),
 114         _CMD("WEBIRC", IRC_WEBIRC, CLIENT_UNKNOWN, 4, 4, 0),
 115         _CMD("WHO", IRC_WHO, CLIENT_USER, 0, 2, 1),
 116         _CMD("WHOIS", IRC_WHOIS, CLIENT_USER|CLIENT_SERVER, 0, -1, 1),
 117         _CMD("WHOWAS", IRC_WHOWAS, CLIENT_USER|CLIENT_SERVER, 0, -1, 0),
 118
 119 #ifdef IRCPLUS
 120         _CMD("CHANINFO", IRC_CHANINFO, CLIENT_SERVER, 0, -1, 0),
 121 # ifdef ICONV
 122         _CMD("CHARCONV", IRC_CHARCONV, CLIENT_USER, 1, 1, 0),
 123 # endif
 124 #endif
 125
 126 #ifndef STRICT_RFC
 127         _CMD("GET",  IRC_QUIT_HTTP, CLIENT_UNKNOWN, 0, -1, 0),
 128         _CMD("POST", IRC_QUIT_HTTP, CLIENT_UNKNOWN, 0, -1, 0),
 129 #endif
 130         _CMD(NULL, NULL, 0, 0, 0, 0) /* End-Mark */
 131 #undef _CMD
 132 };
 133
 134 static void Init_Request PARAMS(( REQUEST *Req ));
 135
 136 static bool Validate_Prefix PARAMS(( CONN_ID Idx, REQUEST *Req, bool *Closed ));
 137 static bool Validate_Command PARAMS(( CONN_ID Idx, REQUEST *Req, bool *Closed ));
 138 static bool Validate_Args PARAMS(( CONN_ID Idx, REQUEST *Req, bool *Closed ));
 139
 140 static bool Handle_Request PARAMS(( CONN_ID Idx, REQUEST *Req ));
 141
 142 static bool ScrubCTCP PARAMS((char *Request));
 143
 144 /**
 145  * Return the pointer to the global "IRC command structure".
 146  * This structure, an array of type "COMMAND" describes all the IRC commands
 147  * implemented by ngIRCd and how to handle them.
 148  * @return Pointer to the global command structure.
 149  */
 150 GLOBAL COMMAND *
 151 Parse_GetCommandStruct( void )
 152 {
 153         return My_Commands;
 154 } /* Parse_GetCommandStruct */
 155
 156
 157 /**
 158  * Parse a command ("request") received from a client.
 159  *
 160  * This function is called after the connection layer received a valid CR+LF
 161  * terminated line of text: we assume that this is a valid IRC command and
 162  * try to do something useful with it :-)
 163  *
 164  * All errors are reported to the client from which the command has been
 165  * received, and if the error is fatal this connection is closed down.
 166  *
 167  * This function is able to parse the syntax as described in RFC 2812,
 168  * section 2.3.
 169  *
 170  * @param Idx Index of the connection from which the command has been received.
 171  * @param Request NULL terminated line of text (the "command").
 172  * @return CONNECTED on success (valid command or "regular" error), DISCONNECTED
 173  *      if a fatal error occurred and the connection has been shut down.
 174  */
 175 GLOBAL bool
 176 Parse_Request( CONN_ID Idx, char *Request )
 177 {
 178         REQUEST req;
 179         char *start, *ptr;
 180         bool closed;
 181
 182         assert( Idx >= 0 );
 183         assert( Request != NULL );
 184
 185 #ifdef SNIFFER
 186         if( NGIRCd_Sniffer ) Log( LOG_DEBUG, " <- connection %d: '%s'.", Idx, Request );
 187 #endif
 188
 189         Init_Request( &req );
 190
 191         /* remove leading & trailing whitespace */
 192         ngt_TrimStr( Request );
 193
 194         if (Conf_ScrubCTCP && ScrubCTCP(Request))
 195                 return true;
 196
 197         if (Request[0] == ':') {
 198                 /* Prefix */
 199                 req.prefix = Request + 1;
 200                 ptr = strchr( Request, ' ' );
 201                 if( ! ptr )
 202                 {
 203                         LogDebug("Connection %d: Parse error: prefix without command!?", Idx);
 204                         return Conn_WriteStr(Idx, "ERROR :Prefix without command");
 205                 }
 206                 *ptr = '\0';
 207 #ifndef STRICT_RFC
 208                 /* ignore multiple spaces between prefix and command */
 209                 while( *(ptr + 1) == ' ' ) ptr++;
 210 #endif
 211                 start = ptr + 1;
 212         }
 213         else start = Request;
 214
 215         ptr = strchr( start, ' ' );
 216         if( ptr )
 217         {
 218                 *ptr = '\0';
 219 #ifndef STRICT_RFC
 220                 /* ignore multiple spaces between parameters */
 221                 while( *(ptr + 1) == ' ' ) ptr++;
 222 #endif
 223         }
 224         req.command = start;
 225
 226         /* Arguments, Parameters */
 227         if( ptr )
 228         {
 229                 start = ptr + 1;
 230                 while( start )
 231                 {
 232                         if( start[0] == ':' )
 233                         {
 234                                 req.argv[req.argc] = start + 1;
 235                                 ptr = NULL;
 236                         }
 237                         else
 238                         {
 239                                 req.argv[req.argc] = start;
 240                                 ptr = strchr( start, ' ' );
 241                                 if( ptr )
 242                                 {
 243                                         *ptr = '\0';
 244 #ifndef STRICT_RFC
 245                                         while( *(ptr + 1) == ' ' ) ptr++;
 246 #endif
 247                                 }
 248                         }
 249
 250                         req.argc++;
 251
 252                         if( start[0] == ':' ) break;
 253                         if( req.argc > 14 ) break;
 254
 255                         if( ptr ) start = ptr + 1;
 256                         else start = NULL;
 257                 }
 258         }
 259
 260         if(!Validate_Prefix(Idx, &req, &closed))
 261                 return !closed;
 262         if(!Validate_Command(Idx, &req, &closed))
 263                 return !closed;
 264         if(!Validate_Args(Idx, &req, &closed))
 265                 return !closed;
 266
 267         return Handle_Request(Idx, &req);
 268 } /* Parse_Request */
 269
 270
 271 /**
 272  * Initialize request structure.
 273  * @param Req Request structure to be initialized.
 274  */
 275 static void
 276 Init_Request( REQUEST *Req )
 277 {
 278         int i;
 279
 280         assert( Req != NULL );
 281
 282         Req->prefix = NULL;
 283         Req->command = NULL;
 284         for( i = 0; i < 15; Req->argv[i++] = NULL );
 285         Req->argc = 0;
 286 } /* Init_Request */
 287
 288
 289 static bool
 290 Validate_Prefix( CONN_ID Idx, REQUEST *Req, bool *Closed )
 291 {
 292         CLIENT *client, *c;
 293
 294         assert( Idx >= 0 );
 295         assert( Req != NULL );
 296
 297         *Closed = false;
 298
 299         client = Conn_GetClient( Idx );
 300         assert( client != NULL );
 301
 302         if (!Req->prefix && Client_Type(client) == CLIENT_SERVER
 303             && !(Conn_Options(Idx) & CONN_RFC1459)
 304             && strcasecmp(Req->command, "ERROR") != 0
 305             && strcasecmp(Req->command, "PING") != 0)
 306         {
 307                 Log(LOG_ERR,
 308                     "Received command without prefix (connection %d, command \"%s\")!?",
 309                     Idx, Req->command);
 310                 if (!Conn_WriteStr(Idx, "ERROR :Prefix missing"))
 311                         *Closed = true;
 312                 return false;
 313         }
 314
 315         if (!Req->prefix)
 316                 return true;
 317
 318         /* only validate if this connection is already registered */
 319         if (Client_Type(client) != CLIENT_USER
 320             && Client_Type(client) != CLIENT_SERVER
 321             && Client_Type(client) != CLIENT_SERVICE) {
 322                 /* not registered, ignore prefix */
 323                 Req->prefix = NULL;
 324                 return true;
 325         }
 326
 327         /* check if client in prefix is known */
 328         c = Client_Search(Req->prefix);
 329         if (!c) {
 330                 if (Client_Type(client) != CLIENT_SERVER) {
 331                         Log(LOG_ERR,
 332                             "Ignoring command with invalid prefix \"%s\" from \"%s\" (connection %d, command \"%s\")!",
 333                             Req->prefix, Client_ID(client), Idx, Req->command);
 334                         if (!Conn_WriteStr(Idx,
 335                                            "ERROR :Invalid prefix \"%s\"",
 336                                            Req->prefix))
 337                                 *Closed = true;
 338                         IRC_SetPenalty(client, 2);
 339                 } else
 340                         LogDebug("Ignoring command with invalid prefix \"%s\" from \"%s\" (connection %d, command \"%s\")!",
 341                             Req->prefix, Client_ID(client), Idx, Req->command);
 342                 return false;
 343         }
 344
 345         /* check if the client named in the prefix is expected
 346          * to come from that direction */
 347         if (Client_NextHop(c) != client) {
 348                 if (Client_Type(client) != CLIENT_SERVER) {
 349                         Log(LOG_ERR,
 350                             "Spoofed prefix \"%s\" from \"%s\" (connection %d, command \"%s\"), closing connection!",
 351                             Req->prefix, Client_ID(client), Idx, Req->command);
 352                         Conn_Close(Idx, NULL, "Spoofed prefix", true);
 353                         *Closed = true;
 354                 } else {
 355                         Log(LOG_WARNING,
 356                             "Ignoring command with spoofed prefix \"%s\" from \"%s\" (connection %d, command \"%s\")!",
 357                             Req->prefix, Client_ID(client), Idx, Req->command);
 358                 }
 359                 return false;
 360         }
 361
 362         return true;
 363 } /* Validate_Prefix */
 364
 365
 366 static bool
 367 Validate_Command( UNUSED CONN_ID Idx, UNUSED REQUEST *Req, bool *Closed )
 368 {
 369         assert( Idx >= 0 );
 370         assert( Req != NULL );
 371         *Closed = false;
 372
 373         return true;
 374 } /* Validate_Command */
 375
 376
 377 static bool
 378 #ifdef STRICT_RFC
 379 Validate_Args(CONN_ID Idx, REQUEST *Req, bool *Closed)
 380 #else
 381 Validate_Args(UNUSED CONN_ID Idx, UNUSED REQUEST *Req, bool *Closed)
 382 #endif
 383 {
 384 #ifdef STRICT_RFC
 385         int i;
 386 #endif
 387
 388         *Closed = false;
 389
 390 #ifdef STRICT_RFC
 391         assert( Idx >= 0 );
 392         assert( Req != NULL );
 393
 394         /* CR and LF are never allowed in command parameters.
 395          * But since we do accept lines terminated only with CR or LF in
 396          * "non-RFC-compliant mode" (besides the correct CR+LF combination),
 397          * this check can only trigger in "strict RFC" mode; therefore we
 398          * optimize it away otherwise ... */
 399         for (i = 0; i < Req->argc; i++) {
 400                 if (strchr(Req->argv[i], '\r') || strchr(Req->argv[i], '\n')) {
 401                         Log(LOG_ERR,
 402                             "Invalid character(s) in parameter (connection %d, command %s)!?",
 403                             Idx, Req->command);
 404                         if (!Conn_WriteStr(Idx,
 405                                            "ERROR :Invalid character(s) in parameter!"))
 406                                 *Closed = true;
 407                         return false;
 408                 }
 409         }
 410 #endif
 411
 412         return true;
 413 } /* Validate_Args */
 414
 415
 416 /* Command is a status code ("numeric") from another server */
 417 static bool
 418 Handle_Numeric(CLIENT *client, REQUEST *Req)
 419 {
 420         static const struct _NUMERIC Numerics[] = {
 421                 {   5, IRC_Num_ISUPPORT },
 422                 {  20, NULL },
 423                 { 376, IRC_Num_ENDOFMOTD }
 424         };
 425         int i, num;
 426         char str[COMMAND_LEN];
 427         CLIENT *prefix, *target = NULL;
 428
 429         /* Determine target */
 430         if (Req->argc > 0) {
 431                 if (strcmp(Req->argv[0], "*") != 0)
 432                         target = Client_Search(Req->argv[0]);
 433                 else
 434                         target = Client_ThisServer();
 435         }
 436
 437         if (!target) {
 438                 /* Status code without target!? */
 439                 if (Req->argc > 0)
 440                         Log(LOG_WARNING,
 441                             "Unknown target for status code %s: \"%s\"",
 442                             Req->command, Req->argv[0]);
 443                 else
 444                         Log(LOG_WARNING,
 445                             "Unknown target for status code %s!",
 446                             Req->command);
 447                 return true;
 448         }
 449         if (target == Client_ThisServer()) {
 450                 /* This server is the target of the numeric */
 451                 num = atoi(Req->command);
 452
 453                 for (i = 0; i < (int) C_ARRAY_SIZE(Numerics); i++) {
 454                         if (num == Numerics[i].numeric) {
 455                                 if (!Numerics[i].function)
 456                                         return CONNECTED;
 457                                 return Numerics[i].function(client, Req);
 458                         }
 459                 }
 460
 461                 LogDebug("Ignored status code %s from \"%s\".",
 462                          Req->command, Client_ID(client));
 463                 return true;
 464         }
 465
 466         /* Determine source */
 467         if (!Req->prefix) {
 468                 Log(LOG_WARNING,
 469                     "Got status code %s from \"%s\" without prefix!?",
 470                     Req->command, Client_ID(client));
 471                 return true;
 472         }
 473
 474         prefix = Client_Search(Req->prefix);
 475         if (! prefix) { /* Oops, unknown prefix!? */
 476                 Log(LOG_WARNING, "Got status code %s from unknown source: \"%s\"", Req->command, Req->prefix);
 477                 return true;
 478         }
 479
 480         /* Forward status code */
 481         strlcpy(str, Req->command, sizeof(str));
 482         for (i = 0; i < Req->argc; i++) {
 483                 if (i < Req->argc - 1)
 484                         strlcat(str, " ", sizeof(str));
 485                 else
 486                         strlcat(str, " :", sizeof(str));
 487                 strlcat(str, Req->argv[i], sizeof(str));
 488         }
 489         return IRC_WriteStrClientPrefix(target, prefix, "%s", str);
 490 }
 491
 492 static bool
 493 Handle_Request( CONN_ID Idx, REQUEST *Req )
 494 {
 495         CLIENT *client;
 496         bool result = CONNECTED;
 497         int client_type;
 498         COMMAND *cmd;
 499
 500         assert( Idx >= 0 );
 501         assert( Req != NULL );
 502         assert( Req->command != NULL );
 503
 504         client = Conn_GetClient( Idx );
 505         assert( client != NULL );
 506
 507         /* Numeric? */
 508         client_type = Client_Type(client);
 509         if ((client_type == CLIENT_SERVER ||
 510              client_type == CLIENT_UNKNOWNSERVER)
 511             && strlen(Req->command) == 3 && atoi(Req->command) > 1)
 512                 return Handle_Numeric(client, Req);
 513
 514         cmd = My_Commands;
 515         while (cmd->name) {
 516                 if (strcasecmp(Req->command, cmd->name) != 0) {
 517                         cmd++;
 518                         continue;
 519                 }
 520
 521                 if (!(client_type & cmd->type)) {
 522                         if (client_type == CLIENT_USER
 523                             && cmd->type & CLIENT_SERVER)
 524                                 return IRC_WriteErrClient(client,
 525                                                  ERR_NOTREGISTEREDSERVER_MSG,
 526                                                  Client_ID(client));
 527                         else
 528                                 return IRC_WriteErrClient(client,
 529                                                 ERR_NOTREGISTERED_MSG,
 530                                                 Client_ID(client));
 531                 }
 532
 533                 if (cmd->penalty)
 534                         IRC_SetPenalty(client, cmd->penalty);
 535
 536                 if (Req->argc < cmd->min_argc ||
 537                     (cmd->max_argc != -1 && Req->argc > cmd->max_argc))
 538                         return IRC_WriteErrClient(client, ERR_NEEDMOREPARAMS_MSG,
 539                                                   Client_ID(client), Req->command);
 540
 541                 /* Command is allowed for this client: call it and count
 542                  * generated bytes in output */
 543                 Conn_ResetWCounter();
 544                 result = (cmd->function)(client, Req);
 545                 cmd->bytes += Conn_WCounter();
 546
 547                 /* Adjust counters */
 548                 if (client_type != CLIENT_SERVER)
 549                         cmd->lcount++;
 550                 else
 551                         cmd->rcount++;
 552
 553                 /* Return result of command (CONNECTED/DISCONNECTED). */
 554                 return result;
 555         }
 556
 557         if (client_type != CLIENT_USER &&
 558             client_type != CLIENT_SERVER &&
 559             client_type != CLIENT_SERVICE )
 560                 return true;
 561
 562         LogDebug("Connection %d: Unknown command \"%s\", %d %s,%s prefix.",
 563                         Client_Conn( client ), Req->command, Req->argc,
 564                         Req->argc == 1 ? "parameter" : "parameters",
 565                         Req->prefix ? "" : " no" );
 566
 567         /* Unknown command and registered connection: generate error: */
 568         if (client_type != CLIENT_SERVER)
 569                 result = IRC_WriteErrClient(client, ERR_UNKNOWNCOMMAND_MSG,
 570                                 Client_ID(client), Req->command);
 571
 572         return result;
 573 } /* Handle_Request */
 574
 575
 576 /**
 577  * Check if incoming messages contains CTCP commands and should be dropped.
 578  *
 579  * @param Request NULL terminated incoming command.
 580  * @returns true, when the message should be dropped.
 581  */
 582 static bool
 583 ScrubCTCP(char *Request)
 584 {
 585         static const char me_cmd[] = "ACTION ";
 586         static const char ctcp_char = 0x1;
 587         bool dropCommand = false;
 588         char *ptr = Request;
 589         char *ptrEnd = strchr(Request, '\0');
 590
 591         if (Request[0] == ':' && ptrEnd > ptr)
 592                 ptr++;
 593
 594         while (ptr != ptrEnd && *ptr != ':')
 595                 ptr++;
 596
 597         if ((ptrEnd - ptr) > 1) {
 598                 ptr++;
 599                 if (*ptr == ctcp_char) {
 600                         dropCommand = true;
 601                         ptr++;
 602                         /* allow /me commands */
 603                         if ((size_t)(ptrEnd - ptr) >= strlen(me_cmd)
 604                             && !strncmp(ptr, me_cmd, strlen(me_cmd)))
 605                                 dropCommand = false;
 606                 }
 607         }
 608         return dropCommand;
 609 }
 610
 611 /* -eof- */