/* * ngIRCd -- The Next Generation IRC Daemon * Copyright (c)2001-2018 Alexander Barton (alex@barton.de) and Contributors. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * Please read the file COPYING, README and AUTHORS for more information. */ #include "portab.h" /** * @file * IRC commands */ #include #include #include #include #include #include "ngircd.h" #include "conn-func.h" #include "conf.h" #include "channel.h" #ifdef ICONV # include "conn-encoding.h" #endif #include "irc-macros.h" #include "irc-write.h" #include "log.h" #include "match.h" #include "messages.h" #include "parse.h" #include "op.h" #include "irc.h" static char *Option_String PARAMS((CONN_ID Idx)); static bool Send_Message PARAMS((CLIENT *Client, REQUEST *Req, int ForceType, bool SendErrors)); static bool Send_Message_Mask PARAMS((CLIENT *from, char *command, char *targetMask, char *message, bool SendErrors)); static bool Help PARAMS((CLIENT *Client, const char *Topic)); /** * Check if a list limit is reached and inform client accordingly. * * @param From The client. * @param Count Reply item count. * @param Limit Reply limit. * @param Name Name of the list. * @return true if list limit has been reached; false otherwise. */ GLOBAL bool IRC_CheckListTooBig(CLIENT *From, const int Count, const int Limit, const char *Name) { assert(From != NULL); assert(Count >= 0); assert(Limit > 0); assert(Name != NULL); if (Count < Limit) return false; (void)IRC_WriteStrClient(From, "NOTICE %s :%s list limit (%d) reached!", Client_ID(From), Name, Limit); IRC_SetPenalty(From, 2); return true; } /** * Handler for the IRC "ERROR" command. * * @param Client The client from which this command has been received. * @param Req Request structure with prefix and all parameters. * @return CONNECTED or DISCONNECTED. */ GLOBAL bool IRC_ERROR(CLIENT *Client, REQUEST *Req) { char *msg; assert( Client != NULL ); assert( Req != NULL ); if (Client_Type(Client) != CLIENT_GOTPASS && Client_Type(Client) != CLIENT_GOTPASS_2813 && Client_Type(Client) != CLIENT_UNKNOWNSERVER && Client_Type(Client) != CLIENT_SERVER && Client_Type(Client) != CLIENT_SERVICE) { LogDebug("Ignored ERROR command from \"%s\" ...", Client_Mask(Client)); IRC_SetPenalty(Client, 2); return CONNECTED; } if (Req->argc < 1) { msg = "Got ERROR command"; Log(LOG_NOTICE, "Got ERROR from \"%s\"!", Client_Mask(Client)); } else { msg = Req->argv[0]; Log(LOG_NOTICE, "Got ERROR from \"%s\": \"%s\"!", Client_Mask(Client), msg); } if (Client_Conn(Client) != NONE) { Conn_Close(Client_Conn(Client), NULL, msg, false); return DISCONNECTED; } return CONNECTED; } /* IRC_ERROR */ /** * Handler for the IRC "KILL" command. * * This function implements the IRC command "KILL" which is used to selectively * disconnect clients. It can be used by IRC operators and servers, for example * to "solve" nick collisions after netsplits. See RFC 2812 section 3.7.1. * * Please note that this function is also called internally, without a real * KILL command being received over the network! Client is Client_ThisServer() * in this case, and the prefix in Req is NULL. * * @param Client The client from which this command has been received or * Client_ThisServer() when generated interanlly. * @param Req Request structure with prefix and all parameters. * @return CONNECTED or DISCONNECTED. */ GLOBAL bool IRC_KILL(CLIENT *Client, REQUEST *Req) { CLIENT *prefix; char reason[COMMAND_LEN]; assert (Client != NULL); assert (Req != NULL); if (Client_Type(Client) != CLIENT_SERVER && !Op_Check(Client, Req)) return Op_NoPrivileges(Client, Req); /* Get prefix (origin); use the client if no prefix is given. */ if (Req->prefix) prefix = Client_Search(Req->prefix); else prefix = Client; /* Log a warning message and use this server as origin when the * prefix (origin) is invalid. And this is the reason why we don't * use the _IRC_GET_SENDER_OR_RETURN_ macro above! */ if (!prefix) { Log(LOG_WARNING, "Got KILL with invalid prefix: \"%s\"!", Req->prefix ); prefix = Client_ThisServer(); } if (Client != Client_ThisServer()) Log(LOG_NOTICE|LOG_snotice, "Got KILL command from \"%s\" for \"%s\": \"%s\".", Client_Mask(prefix), Req->argv[0], Req->argv[1]); /* Build reason string: Prefix the "reason" if the originator is a * regular user, so users can't spoof KILLs of servers. */ if (Client_Type(Client) == CLIENT_USER) snprintf(reason, sizeof(reason), "KILLed by %s: %s", Client_ID(Client), Req->argv[1]); else strlcpy(reason, Req->argv[1], sizeof(reason)); return IRC_KillClient(Client, prefix, Req->argv[0], reason); } /** * Handler for the IRC "NOTICE" command. * * @param Client The client from which this command has been received. * @param Req Request structure with prefix and all parameters. * @return CONNECTED or DISCONNECTED. */ GLOBAL bool IRC_NOTICE(CLIENT *Client, REQUEST *Req) { return Send_Message(Client, Req, CLIENT_USER, false); } /* IRC_NOTICE */ /** * Handler for the IRC "PRIVMSG" command. * * @param Client The client from which this command has been received. * @param Req Request structure with prefix and all parameters. * @return CONNECTED or DISCONNECTED. */ GLOBAL bool IRC_PRIVMSG(CLIENT *Client, REQUEST *Req) { return Send_Message(Client, Req, CLIENT_USER, true); } /* IRC_PRIVMSG */ /** * Handler for the IRC "SQUERY" command. * * @param Client The client from which this command has been received. * @param Req Request structure with prefix and all parameters. * @return CONNECTED or DISCONNECTED. */ GLOBAL bool IRC_SQUERY(CLIENT *Client, REQUEST *Req) { return Send_Message(Client, Req, CLIENT_SERVICE, true); } /* IRC_SQUERY */ /* * Handler for the IRC "TRACE" command. * * @param Client The client from which this command has been received. * @param Req Request structure with prefix and all parameters. * @return CONNECTED or DISCONNECTED. */ GLOBAL bool IRC_TRACE(CLIENT *Client, REQUEST *Req) { CLIENT *from, *target, *c; CONN_ID idx, idx2; char user[CLIENT_USER_LEN]; assert(Client != NULL); assert(Req != NULL); _IRC_GET_SENDER_OR_RETURN_(from, Req, Client) _IRC_GET_TARGET_SERVER_OR_RETURN_(target, Req, 0, from) /* Forward command to other server? */ if (target != Client_ThisServer()) { /* Send RPL_TRACELINK back to initiator */ idx = Client_Conn(Client); assert(idx > NONE); idx2 = Client_Conn(Client_NextHop(target)); assert(idx2 > NONE); if (!IRC_WriteStrClient(from, RPL_TRACELINK_MSG, Client_ID(from), PACKAGE_NAME, PACKAGE_VERSION, Client_ID(target), Client_ID(Client_NextHop(target)), Option_String(idx2), (long)(time(NULL) - Conn_StartTime(idx2)), Conn_SendQ(idx), Conn_SendQ(idx2))) return DISCONNECTED; /* Forward command */ IRC_WriteStrClientPrefix(target, from, "TRACE %s", Req->argv[0]); return CONNECTED; } /* Infos about all connected servers */ c = Client_First(); while (c) { if (Client_Conn(c) > NONE) { /* Local client */ if (Client_Type(c) == CLIENT_SERVER) { /* Server link */ strlcpy(user, Client_User(c), sizeof(user)); if (user[0] == '~') strlcpy(user, "unknown", sizeof(user)); if (!IRC_WriteStrClient(from, RPL_TRACESERVER_MSG, Client_ID(from), Client_ID(c), user, Client_Hostname(c), Client_Mask(Client_ThisServer()), Option_String(Client_Conn(c)))) return DISCONNECTED; } if (Client_Type(c) == CLIENT_USER && Client_HasMode(c, 'o')) { /* IRC Operator */ if (!IRC_WriteStrClient(from, RPL_TRACEOPERATOR_MSG, Client_ID(from), Client_ID(c))) return DISCONNECTED; } } c = Client_Next( c ); } return IRC_WriteStrClient(from, RPL_TRACEEND_MSG, Client_ID(from), Conf_ServerName, PACKAGE_NAME, PACKAGE_VERSION, NGIRCd_DebugLevel); } /* IRC_TRACE */ /** * Handler for the IRC "HELP" command. * * @param Client The client from which this command has been received. * @param Req Request structure with prefix and all parameters. * @return CONNECTED or DISCONNECTED. */ GLOBAL bool IRC_HELP(CLIENT *Client, REQUEST *Req) { COMMAND *cmd; assert(Client != NULL); assert(Req != NULL); if ((Req->argc == 0 && array_bytes(&Conf_Helptext) > 0) || (Req->argc >= 1 && strcasecmp(Req->argv[0], "Commands") != 0)) { /* Help text available and requested */ if (Req->argc >= 1) return Help(Client, Req->argv[0]); if (!Help(Client, "Intro")) return DISCONNECTED; return CONNECTED; } cmd = Parse_GetCommandStruct(); while(cmd->name) { if (!IRC_WriteStrClient(Client, "NOTICE %s :%s", Client_ID(Client), cmd->name)) return DISCONNECTED; cmd++; } return CONNECTED; } /* IRC_HELP */ /** * Kill an client identified by its nick name. * * Please note that after killig a client, its CLIENT cond CONNECTION * structures are invalid. So the caller must make sure on its own not to * access data of probably killed clients after calling this function! * * @param Client The client from which the command leading to the KILL has * been received, or NULL. The KILL will no be forwarded in this * direction. Only relevant when From is set, too. * @param From The client from which the command originated, or NULL for the local server. * @param Nick The nick name to kill. * @param Reason Text to send as reason to the client and other servers. */ GLOBAL bool IRC_KillClient(CLIENT *Client, CLIENT *From, const char *Nick, const char *Reason) { const char *msg; CONN_ID my_conn = NONE, conn; CLIENT *c; assert(Nick != NULL); assert(Reason != NULL); /* Do we know such a client in the network? */ c = Client_Search(Nick); if (!c) { LogDebug("Client with nick \"%s\" is unknown, not forwaring.", Nick); return CONNECTED; } if (Client_Type(c) != CLIENT_USER && Client_Type(c) != CLIENT_GOTNICK && Client_Type(c) != CLIENT_SERVICE) { /* Target of this KILL is not a regular user, this is * invalid! So we ignore this case if we received a * regular KILL from the network and try to kill the * client/connection anyway (but log an error!) if the * origin is the local server. */ if (Client != Client_ThisServer()) { /* Invalid KILL received from remote */ if (Client_Type(c) == CLIENT_SERVER) msg = ERR_CANTKILLSERVER_MSG; else msg = ERR_NOPRIVILEGES_MSG; return IRC_WriteErrClient(Client, msg, Client_ID(Client)); } Log(LOG_ERR, "Got KILL for invalid client type: %d, \"%s\"!", Client_Type(c), Nick); } /* Inform other servers */ IRC_WriteStrServersPrefix(From ? Client : NULL, From ? From : Client_ThisServer(), "KILL %s :%s", Nick, Reason); /* Save ID of this connection */ if (Client) my_conn = Client_Conn(Client); /* Kill the client NOW: * - Close the local connection (if there is one), * - Destroy the CLIENT structure for remote clients. * Note: Conn_Close() removes the CLIENT structure as well. */ conn = Client_Conn(c); if(conn > NONE) Conn_Close(conn, NULL, Reason, true); else Client_Destroy(c, NULL, Reason, false); /* Are we still connected or were we killed, too? */ if (my_conn > NONE && Conn_GetClient(my_conn)) return CONNECTED; else return DISCONNECTED; } /** * Send help for a given topic to the client. * * @param Client The client requesting help. * @param Topic The help topic requested. * @return CONNECTED or DISCONNECTED. */ static bool Help(CLIENT *Client, const char *Topic) { char *line; size_t helptext_len, len_str, idx_start, lines = 0; bool in_article = false; assert(Client != NULL); assert(Topic != NULL); helptext_len = array_bytes(&Conf_Helptext); line = array_start(&Conf_Helptext); while (helptext_len > 0) { len_str = strlen(line) + 1; assert(helptext_len >= len_str); helptext_len -= len_str; if (in_article) { /* The first character in each article text line must * be a TAB (ASCII 9) character which will be stripped * in the output. If it is not a TAB, the end of the * article has been reached. */ if (line[0] != '\t') { if (lines > 0) return CONNECTED; else break; } /* A single '.' character indicates an empty line */ if (line[1] == '.' && line[2] == '\0') idx_start = 2; else idx_start = 1; if (!IRC_WriteStrClient(Client, "NOTICE %s :%s", Client_ID(Client), &line[idx_start])) return DISCONNECTED; lines++; } else { if (line[0] == '-' && line[1] == ' ' && strcasecmp(&line[2], Topic) == 0) in_article = true; } line += len_str; } /* Help topic not found (or empty)! */ if (!IRC_WriteStrClient(Client, "NOTICE %s :No help for \"%s\" found!", Client_ID(Client), Topic)) return DISCONNECTED; return CONNECTED; } /** * Get pointer to a static string representing the connection "options". * * @param Idx Connection index. * @return Pointer to static (global) string buffer. */ static char * #if defined(SSL_SUPPORT) || defined(ZLIB) Option_String(CONN_ID Idx) { static char option_txt[8]; UINT16 options; assert(Idx != NONE); options = Conn_Options(Idx); strcpy(option_txt, "F"); /* No idea what this means, but the * original ircd sends it ... */ #ifdef SSL_SUPPORT if(options & CONN_SSL) /* SSL encrypted link */ strlcat(option_txt, "s", sizeof(option_txt)); #endif #ifdef ZLIB if(options & CONN_ZIP) /* zlib compression enabled */ strlcat(option_txt, "z", sizeof(option_txt)); #endif return option_txt; #else Option_String(UNUSED CONN_ID Idx) { return ""; #endif } /* Option_String */ /** * Send a message to target(s). * * This function is used by IRC_{PRIVMSG|NOTICE|SQUERY} to actualy * send the message(s). * * @param Client The client from which this command has been received. * @param Req Request structure with prefix and all parameters. * @param ForceType Required type of the destination of the message(s). * @param SendErrors Whether to report errors back to the client or not. * @return CONNECTED or DISCONNECTED. */ static bool Send_Message(CLIENT * Client, REQUEST * Req, int ForceType, bool SendErrors) { CLIENT *cl, *from; CL2CHAN *cl2chan; CHANNEL *chan; char *currentTarget = Req->argv[0]; char *strtok_last = NULL; char *message = NULL; char *targets[MAX_HNDL_TARGETS]; int i, target_nr = 0; assert(Client != NULL); assert(Req != NULL); if (Req->argc == 0) { if (!SendErrors) return CONNECTED; return IRC_WriteErrClient(Client, ERR_NORECIPIENT_MSG, Client_ID(Client), Req->command); } if (Req->argc == 1) { if (!SendErrors) return CONNECTED; return IRC_WriteErrClient(Client, ERR_NOTEXTTOSEND_MSG, Client_ID(Client)); } if (Req->argc > 2) { if (!SendErrors) return CONNECTED; return IRC_WriteErrClient(Client, ERR_NEEDMOREPARAMS_MSG, Client_ID(Client), Req->command); } if (Client_Type(Client) == CLIENT_SERVER && Req->prefix) from = Client_Search(Req->prefix); else from = Client; if (!from) return IRC_WriteErrClient(Client, ERR_NOSUCHNICK_MSG, Client_ID(Client), Req->prefix); #ifdef ICONV if (Client_Conn(Client) > NONE) message = Conn_EncodingFrom(Client_Conn(Client), Req->argv[1]); else #endif message = Req->argv[1]; /* handle msgtarget = msgto *("," msgto) */ currentTarget = strtok_r(currentTarget, ",", &strtok_last); ngt_UpperStr(Req->command); /* Please note that "currentTarget" is NULL when the target contains * the separator character only, e. g. "," or ",,,," etc.! */ while (currentTarget) { /* Make sure that there hasn't been such a target already: */ targets[target_nr++] = currentTarget; for(i = 0; i < target_nr - 1; i++) { if (strcasecmp(currentTarget, targets[i]) == 0) goto send_next_target; } /* Check for and handle valid of form: * RFC 2812 2.3.1: * msgto = channel / ( user [ "%" host ] "@" servername ) * msgto =/ ( user "%" host ) / targetmask * msgto =/ nickname / ( nickname "!" user "@" host ) */ if (strchr(currentTarget, '!') == NULL) /* nickname */ cl = Client_Search(currentTarget); else cl = NULL; if (cl == NULL) { /* If currentTarget isn't a nickname check for: * user ["%" host] "@" servername * user "%" host * nickname "!" user "@" host */ char target[COMMAND_LEN]; char * nick = NULL; char * user = NULL; char * host = NULL; char * server = NULL; strlcpy(target, currentTarget, COMMAND_LEN); server = strchr(target, '@'); if (server) { *server = '\0'; server++; } host = strchr(target, '%'); if (host) { *host = '\0'; host++; } user = strchr(target, '!'); if (user) { /* msgto form: nick!user@host */ *user = '\0'; user++; nick = target; host = server; /* not "@server" but "@host" */ } else { user = target; } for (cl = Client_First(); cl != NULL; cl = Client_Next(cl)) { if (Client_Type(cl) != CLIENT_USER && Client_Type(cl) != CLIENT_SERVICE) continue; if (nick != NULL && host != NULL) { if (strcasecmp(nick, Client_ID(cl)) == 0 && strcasecmp(user, Client_User(cl)) == 0 && strcasecmp(host, Client_HostnameDisplayed(cl)) == 0) break; else continue; } if (strcasecmp(user, Client_User(cl)) != 0) continue; if (host != NULL && strcasecmp(host, Client_HostnameDisplayed(cl)) != 0) continue; if (server != NULL && strcasecmp(server, Client_ID(Client_Introducer(cl))) != 0) continue; break; } } if (cl) { /* Target is a user, enforce type */ #ifndef STRICT_RFC if (Client_Type(cl) != ForceType && !(ForceType == CLIENT_USER && (Client_Type(cl) == CLIENT_USER || Client_Type(cl) == CLIENT_SERVICE))) { #else if (Client_Type(cl) != ForceType) { #endif if (SendErrors && !IRC_WriteErrClient( from, ERR_NOSUCHNICK_MSG,Client_ID(from), currentTarget)) return DISCONNECTED; goto send_next_target; } #ifndef STRICT_RFC if (ForceType == CLIENT_SERVICE && (Conn_Options(Client_Conn(Client_NextHop(cl))) & CONN_RFC1459)) { /* SQUERY command but RFC 1459 link: convert * request to PRIVMSG command */ Req->command = "PRIVMSG"; } #endif if (Client_HasMode(cl, 'b') && !Client_HasMode(from, 'R') && !Client_HasMode(from, 'o') && !(Client_Type(from) == CLIENT_SERVER) && !(Client_Type(from) == CLIENT_SERVICE)) { if (SendErrors && !IRC_WriteErrClient(from, ERR_NONONREG_MSG, Client_ID(from), Client_ID(cl))) return DISCONNECTED; goto send_next_target; } if (Client_HasMode(cl, 'C') && !Client_HasMode(from, 'o') && !(Client_Type(from) == CLIENT_SERVER) && !(Client_Type(from) == CLIENT_SERVICE)) { cl2chan = Channel_FirstChannelOf(cl); while (cl2chan) { chan = Channel_GetChannel(cl2chan); if (Channel_IsMemberOf(chan, from)) break; cl2chan = Channel_NextChannelOf(cl, cl2chan); } if (!cl2chan) { if (SendErrors && !IRC_WriteErrClient( from, ERR_NOTONSAMECHANNEL_MSG, Client_ID(from), Client_ID(cl))) return DISCONNECTED; goto send_next_target; } } if (SendErrors && (Client_Type(Client) != CLIENT_SERVER) && Client_HasMode(cl, 'a')) { /* Target is away */ if (!IRC_WriteStrClient(from, RPL_AWAY_MSG, Client_ID(from), Client_ID(cl), Client_Away(cl))) return DISCONNECTED; } if (Client_Conn(from) > NONE) { Conn_UpdateIdle(Client_Conn(from)); } if (!IRC_WriteStrClientPrefix(cl, from, "%s %s :%s", Req->command, Client_ID(cl), message)) return DISCONNECTED; } else if (ForceType != CLIENT_SERVICE && (chan = Channel_Search(currentTarget))) { /* Target is a channel */ if (!Channel_Write(chan, from, Client, Req->command, SendErrors, message)) return DISCONNECTED; } else if (ForceType != CLIENT_SERVICE && strchr("$#", currentTarget[0]) && strchr(currentTarget, '.')) { /* $#: server/host mask, RFC 2812, sec. 3.3.1 */ if (!Send_Message_Mask(from, Req->command, currentTarget, message, SendErrors)) return DISCONNECTED; } else { if (!SendErrors) return CONNECTED; if (!IRC_WriteErrClient(from, ERR_NOSUCHNICK_MSG, Client_ID(from), currentTarget)) return DISCONNECTED; } send_next_target: currentTarget = strtok_r(NULL, ",", &strtok_last); if (!currentTarget) break; Conn_SetPenalty(Client_Conn(Client), 1); if (target_nr >= MAX_HNDL_TARGETS) { /* Too many targets given! */ return IRC_WriteErrClient(Client, ERR_TOOMANYTARGETS_MSG, currentTarget); } } return CONNECTED; } /* Send_Message */ /** * Send a message to "target mask" target(s). * * See RFC 2812, sec. 3.3.1 for details. * * @param from The client from which this command has been received. * @param command The command to use (PRIVMSG, NOTICE, ...). * @param targetMask The "target mask" (will be verified by this function). * @param message The message to send. * @param SendErrors Whether to report errors back to the client or not. * @return CONNECTED or DISCONNECTED. */ static bool Send_Message_Mask(CLIENT * from, char * command, char * targetMask, char * message, bool SendErrors) { CLIENT *cl; bool client_match; char *mask = targetMask + 1; const char *check_wildcards; cl = NULL; if (!Client_HasMode(from, 'o')) { if (!SendErrors) return true; return IRC_WriteErrClient(from, ERR_NOPRIVILEGES_MSG, Client_ID(from)); } /* * RFC 2812, sec. 3.3.1 requires that targetMask have at least one * dot (".") and no wildcards ("*", "?") following the last one. */ check_wildcards = strrchr(targetMask, '.'); if (!check_wildcards || check_wildcards[strcspn(check_wildcards, "*?")]) { if (!SendErrors) return true; return IRC_WriteErrClient(from, ERR_WILDTOPLEVEL_MSG, targetMask); } if (targetMask[0] == '#') { /* #: hostmask, see RFC 2812, sec. 3.3.1 */ for (cl = Client_First(); cl != NULL; cl = Client_Next(cl)) { if (Client_Type(cl) != CLIENT_USER) continue; client_match = MatchCaseInsensitive(mask, Client_Hostname(cl)); if (client_match) if (!IRC_WriteStrClientPrefix(cl, from, "%s %s :%s", command, Client_ID(cl), message)) return false; } } else { /* $: server mask, see RFC 2812, sec. 3.3.1 */ assert(targetMask[0] == '$'); for (cl = Client_First(); cl != NULL; cl = Client_Next(cl)) { if (Client_Type(cl) != CLIENT_USER) continue; client_match = MatchCaseInsensitive(mask, Client_ID(Client_Introducer(cl))); if (client_match) if (!IRC_WriteStrClientPrefix(cl, from, "%s %s :%s", command, Client_ID(cl), message)) return false; } } return CONNECTED; } /* Send_Message_Mask */ /* -eof- */