2 * InspIRCd -- Internet Relay Chat Daemon
4 * Copyright (C) 2009 Daniel De Graaf <danieldg@inspircd.org>
5 * Copyright (C) 2008 Robin Burchell <robin+git@viroteck.net>
7 * This file is part of InspIRCd. InspIRCd is free software: you can
8 * redistribute it and/or modify it under the terms of the GNU General Public
9 * License as published by the Free Software Foundation, version 2.
11 * This program is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
13 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
23 #include "treesocket.h"
26 /* $ModDep: m_spanningtree/utils.h m_spanningtree/treesocket.h */
30 * Yes, this function looks a little ugly.
31 * However, in some circumstances we may not have a User, so we need to do things this way.
32 * Returns 1 if colliding local client, 2 if colliding remote, 3 if colliding both.
33 * Sends SAVEs as appropriate and forces nickchanges too.
35 int TreeSocket::DoCollision(User *u, time_t remotets, const std::string &remoteident, const std::string &remoteip, const std::string &remoteuid)
38 * Under old protocol rules, we would have had to kill both clients.
40 * These days, we have UID. And, so what we do is, force nick change client(s)
41 * involved according to timestamp rules.
45 * Force nick change on OLDER timestamped client
47 * Force nick change on NEWER timestamped client
51 * This stops abusive use of collisions, simplifies problems with loops, and so on.
54 bool bChangeLocal = true;
55 bool bChangeRemote = true;
57 /* for brevity, don't use the User - use defines to avoid any copy */
58 #define localts u->age
59 #define localident u->ident
60 #define localip u->GetIPString()
62 /* mmk. let's do this again. */
63 if (remotets == localts)
65 /* equal. fuck them both! do nada, let the handler at the bottom figure this out. */
69 /* fuck. now it gets complex. */
71 /* first, let's see if ident@host matches. */
72 bool SamePerson = (localident == remoteident)
73 && (localip == remoteip);
76 * if ident@ip is equal, and theirs is newer, or
77 * ident@ip differ, and ours is newer
79 if((SamePerson && remotets < localts) ||
80 (!SamePerson && remotets > localts))
82 /* remote needs to change */
87 /* ours needs to change */
88 bChangeRemote = false;
93 * Cheat a little here. Instead of a dedicated command to change UID,
94 * use SAVE and accept the losing client with its UID (as we know the SAVE will
95 * not fail under any circumstances -- UIDs are netwide exclusive).
97 * This means that each side of a collide will generate one extra NICK back to where
98 * they have just linked (and where it got the SAVE from), however, it will
99 * be dropped harmlessly as it will come in as :928AAAB NICK 928AAAB, and we already
100 * have 928AAAB's nick set to that.
107 * Local-side nick needs to change. Just in case we are hub, and
108 * this "local" nick is actually behind us, send an SAVE out.
110 parameterlist params;
111 params.push_back(u->uuid);
112 params.push_back(ConvToStr(u->age));
113 Utils->DoOneToMany(ServerInstance->Config->GetSID(),"SAVE",params);
115 u->ForceNickChange(u->uuid);
122 User *remote = ServerInstance->FindUUID(remoteuid);
124 * remote side needs to change. If this happens, we will modify
125 * the UID or halt the propagation of the nick change command,
126 * so other servers don't need to see the SAVE
128 WriteLine(":"+ServerInstance->Config->GetSID()+" SAVE "+remoteuid+" "+ ConvToStr(remotets));
132 /* nick change collide. Force change their nick. */
133 remote->ForceNickChange(remoteuid);