/* * InspIRCd -- Internet Relay Chat Daemon * * Copyright (C) 2009-2010 Daniel De Graaf * Copyright (C) 2008 Robin Burchell * Copyright (C) 2008 Dennis Friis * Copyright (C) 2008 Craig Edwards * * This file is part of InspIRCd. InspIRCd 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, version 2. * * This program is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more * details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ #include "inspircd.h" #include "commands.h" #include "treeserver.h" #include "treesocket.h" /** FJOIN, almost identical to TS6 SJOIN, except for nicklist handling. */ CmdResult CommandFJoin::Handle(const std::vector& params, User *srcuser) { SpanningTreeUtilities* Utils = ((ModuleSpanningTree*)(Module*)creator)->Utils; /* 1.1+ FJOIN works as follows: * * Each FJOIN is sent along with a timestamp, and the side with the lowest * timestamp 'wins'. From this point on we will refer to this side as the * winner. The side with the higher timestamp loses, from this point on we * will call this side the loser or losing side. This should be familiar to * anyone who's dealt with dreamforge or TS6 before. * * When two sides of a split heal and this occurs, the following things * will happen: * * If the timestamps are exactly equal, both sides merge their privilages * and users, as in InspIRCd 1.0 and ircd2.8. The channels have not been * re-created during a split, this is safe to do. * * If the timestamps are NOT equal, the losing side removes all of its * modes from the channel, before introducing new users into the channel * which are listed in the FJOIN command's parameters. The losing side then * LOWERS its timestamp value of the channel to match that of the winning * side, and the modes of the users of the winning side are merged in with * the losing side. * * The winning side on the other hand will ignore all user modes from the * losing side, so only its own modes get applied. Life is simple for those * who succeed at internets. :-) * * Syntax: * : FJOIN :[[modes,] [[modes,] ... ]] * The last parameter is a list consisting of zero or more (modelist, uuid) * pairs (permanent channels may have zero users). The mode list for each * user is a concatenation of the mode letters the user has on the channel * (e.g.: "ov" if the user is opped and voiced). The order of the mode letters * are not important but if a server ecounters an unknown mode letter, it will * drop the link to avoid desync. * * InspIRCd 2.0 and older required a comma before the uuid even if the user * had no prefix modes on the channel, InspIRCd 2.2 and later does not require * a comma in this case anymore. * */ time_t TS = ConvToInt(params[1]); if (!TS) { ServerInstance->Logs->Log("m_spanningtree", LOG_DEFAULT, "*** BUG? *** TS of 0 sent to FJOIN. Are some services authors smoking craq, or is it 1970 again?. Dropped."); ServerInstance->SNO->WriteToSnoMask('d', "WARNING: The server %s is sending FJOIN with a TS of zero. Total craq. Command was dropped.", srcuser->server.c_str()); return CMD_INVALID; } const std::string& channel = params[0]; Channel* chan = ServerInstance->FindChan(channel); bool apply_other_sides_modes = true; if (!chan) { chan = new Channel(channel, TS); } else { time_t ourTS = chan->age; if (TS != ourTS) { ServerInstance->SNO->WriteToSnoMask('d', "Merge FJOIN received for %s, ourTS: %lu, TS: %lu, difference: %lu", chan->name.c_str(), (unsigned long)ourTS, (unsigned long)TS, (unsigned long)(ourTS - TS)); /* If our TS is less than theirs, we dont accept their modes */ if (ourTS < TS) { apply_other_sides_modes = false; } else if (ourTS > TS) { /* Our TS greater than theirs, clear all our modes from the channel, accept theirs. */ if (Utils->AnnounceTSChange) chan->WriteChannelWithServ(ServerInstance->Config->ServerName, "NOTICE %s :TS for %s changed from %lu to %lu", chan->name.c_str(), channel.c_str(), (unsigned long) ourTS, (unsigned long) TS); // while the name is equal in case-insensitive compare, it might differ in case; use the remote version chan->name = channel; chan->age = TS; chan->ClearInvites(); CommandFJoin::RemoveStatus(chan); // XXX: If the channel does not exist in the chan hash at this point, create it so the remote modes can be applied on it. // This happens to 0-user permanent channels on the losing side, because those are removed (from the chan hash, then // deleted later) as soon as the permchan mode is removed from them. if (ServerInstance->FindChan(channel) == NULL) { chan = new Channel(channel, TS); } } } } /* First up, apply their channel modes if they won the TS war */ if (apply_other_sides_modes) { std::vector modelist; modelist.push_back(channel); /* Remember, params[params.size() - 1] is userlist, and we don't want to apply *that* */ modelist.insert(modelist.end(), params.begin()+2, params.end()-1); ServerInstance->SendMode(modelist, srcuser); } irc::modestacker modestack(true); TreeSocket* src_socket = Utils->FindServer(srcuser->server)->GetRoute()->GetSocket(); /* Now, process every 'modes,uuid' pair */ irc::tokenstream users(*params.rbegin()); std::string item; irc::modestacker* modestackptr = (apply_other_sides_modes ? &modestack : NULL); while (users.GetToken(item)) { if (!ProcessModeUUIDPair(item, src_socket, chan, modestackptr)) return CMD_INVALID; } /* Flush mode stacker if we lost the FJOIN or had equal TS */ if (apply_other_sides_modes) CommandFJoin::ApplyModeStack(srcuser, chan, modestack); return CMD_SUCCESS; } bool CommandFJoin::ProcessModeUUIDPair(const std::string& item, TreeSocket* src_socket, Channel* chan, irc::modestacker* modestack) { std::string::size_type comma = item.find(','); // Comma not required anymore if the user has no modes std::string uuid = ((comma == std::string::npos) ? item : item.substr(comma+1)); User* who = ServerInstance->FindUUID(uuid); if (!who) { // Probably KILLed, ignore return true; } /* Check that the user's 'direction' is correct */ SpanningTreeUtilities* Utils = ((ModuleSpanningTree*)(Module*)creator)->Utils; TreeServer* route_back_again = Utils->BestRouteTo(who->server); if ((!route_back_again) || (route_back_again->GetSocket() != src_socket)) { return true; } /* Check if the user received at least one mode */ if ((modestack) && (comma > 0) && (comma != std::string::npos)) { /* Iterate through the modes and see if they are valid here, if so, apply */ std::string::const_iterator commait = item.begin()+comma; for (std::string::const_iterator i = item.begin(); i != commait; ++i) { if (!ServerInstance->Modes->FindMode(*i, MODETYPE_CHANNEL)) { ServerInstance->SNO->WriteToSnoMask('d', "Unrecognised mode '%c' for a user in FJOIN, dropping link", *i); return false; } /* Add any modes this user had to the mode stack */ modestack->Push(*i, who->nick); } } chan->ForceJoin(who, NULL, route_back_again->bursting); return true; } void CommandFJoin::RemoveStatus(Channel* c) { irc::modestacker stack(false); for (char modeletter = 'A'; modeletter <= 'z'; ++modeletter) { ModeHandler* mh = ServerInstance->Modes->FindMode(modeletter, MODETYPE_CHANNEL); /* Passing a pointer to a modestacker here causes the mode to be put onto the mode stack, * rather than applied immediately. Module unloads require this to be done immediately, * for this function we require tidyness instead. Fixes bug #493 */ if (mh) mh->RemoveMode(c, &stack); } ApplyModeStack(ServerInstance->FakeClient, c, stack); } void CommandFJoin::ApplyModeStack(User* srcuser, Channel* c, irc::modestacker& stack) { parameterlist stackresult; stackresult.push_back(c->name); while (stack.GetStackedLine(stackresult)) { ServerInstance->SendMode(stackresult, srcuser); stackresult.erase(stackresult.begin() + 1, stackresult.end()); } }