/*
* InspIRCd -- Internet Relay Chat Daemon
*
* Copyright (C) 2009 Daniel De Graaf <danieldg@inspircd.org>
* Copyright (C) 2007, 2009 Robin Burchell <robin+git@viroteck.net>
*
* 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 <http://www.gnu.org/licenses/>.
*/
#include "inspircd.h"
/* $ModDesc: Provides channel mode +F (nick flood protection) */
/** Holds settings and state associated with channel mode +F
*/
class nickfloodsettings
{
public:
int secs;
int nicks;
time_t reset;
time_t unlocktime;
int counter;
bool locked;
nickfloodsettings(int b, int c) : secs(b), nicks(c)
{
reset = ServerInstance->Time() + secs;
counter = 0;
locked = false;
};
void addnick()
{
counter++;
if (ServerInstance->Time() > reset)
{
counter = 0;
reset = ServerInstance->Time() + secs;
}
}
bool shouldlock()
{
/* XXX HACK: using counter + 1 here now to allow the counter to only be incremented
* on successful nick changes; this will be checked before the counter is
* incremented.
*/
return (counter + 1 >= this->nicks);
}
void clear()
{
counter = 0;
}
bool islocked()
{
if (locked)
{
if (ServerInstance->Time() > unlocktime)
{
locked = false;
return false;
}
else
{
return true;
}
}
return false;
}
void lock()
{
locked = true;
unlocktime = ServerInstance->Time() + 60;
}
};
/** Handles channel mode +j
*/
class NickFlood : public ModeHandler
{
public:
SimpleExtItem<nickfloodsettings> ext;
NickFlood(Module* Creator) : ModeHandler(Creator, "nickflood", 'F', PARAM_SETONLY, MODETYPE_CHANNEL),
ext("nickflood", Creator) { }
ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string ¶meter, bool adding)
{
nickfloodsettings *f = ext.get(channel);
if (adding)
{
char ndata[MAXBUF];
char* data = ndata;
strlcpy(ndata,parameter.c_str(),MAXBUF);
char* nicks = data;
char* secs = NULL;
while (*data)
{
if (*data == ':')
{
*data = 0;
data++;
secs = data;
break;
}
else data++;
}
if (secs)
{
/* Set up the flood parameters for this channel */
int nnicks = atoi(nicks);
int nsecs = atoi(secs);
if ((nnicks<1) || (nsecs<1))
{
source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
parameter.clear();
return MODEACTION_DENY;
}
else
{
if (!f)
{
parameter = ConvToStr(nnicks) + ":" +ConvToStr(nsecs);
f = new nickfloodsettings(nsecs, nnicks);
ext.set(channel, f);
channel->SetModeParam('F', parameter);
return MODEACTION_ALLOW;
}
else
{
std::string cur_param = channel->GetModeParameter('F');
parameter = ConvToStr(nnicks) + ":" +ConvToStr(nsecs);
if (cur_param == parameter)
{
// mode params match
return MODEACTION_DENY;
}
else
{
// new mode param, replace old with new
if ((nsecs > 0) && (nnicks > 0))
{
f = new nickfloodsettings(nsecs, nnicks);
ext.set(channel, f);
channel->SetModeParam('F', parameter);
return MODEACTION_ALLOW;
}
else
{
return MODEACTION_DENY;
}
}
}
}
}
else
{
source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
return MODEACTION_DENY;
}
}
else
{
if (f)
{
ext.unset(channel);
channel->SetModeParam('F', "");
return MODEACTION_ALLOW;
}
}
return MODEACTION_DENY;
}
};
class ModuleNickFlood : public Module
{
NickFlood nf;
public:
ModuleNickFlood()
: nf(this)
{
if (!ServerInstance->Modes->AddMode(&nf))
throw ModuleException("Could not add new modes!");
ServerInstance->Extensions.Register(&nf.ext);
Implementation eventlist[] = { I_OnUserPreNick, I_OnUserPostNick };
ServerInstance->Modules->Attach(eventlist, this, 2);
}
ModResult OnUserPreNick(User* user, const std::string &newnick)
{
if (ServerInstance->NICKForced.get(user)) /* Allow forced nick changes */
return MOD_RES_PASSTHRU;
for (UCListIter i = user->chans.begin(); i != user->chans.end(); i++)
{
Channel *channel = *i;
ModResult res;
nickfloodsettings *f = nf.ext.get(channel);
if (f)
{
res = ServerInstance->OnCheckExemption(user,channel,"nickflood");
if (res == MOD_RES_ALLOW)
continue;
if (f->islocked())
{
user->WriteNumeric(447, "%s :%s has been locked for nickchanges for 60 seconds because there have been more than %d nick changes in %d seconds", user->nick.c_str(), channel->name.c_str(), f->nicks, f->secs);
return MOD_RES_DENY;
}
if (f->shouldlock())
{
f->clear();
f->lock();
channel->WriteChannelWithServ((char*)ServerInstance->Config->ServerName.c_str(), "NOTICE %s :No nick changes are allowed for 60 seconds because there have been more than %d nick changes in %d seconds.", channel->name.c_str(), f->nicks, f->secs);
return MOD_RES_DENY;
}
}
}
return MOD_RES_PASSTHRU;
}
/*
* XXX: HACK: We do the increment on the *POST* event here (instead of all together) because we have no way of knowing whether other modules would block a nickchange.
*/
void OnUserPostNick(User* user, const std::string &oldnick)
{
if (isdigit(user->nick[0])) /* allow switches to UID */
return;
for (UCListIter i = user->chans.begin(); i != user->chans.end(); ++i)
{
Channel *channel = *i;
ModResult res;
nickfloodsettings *f = nf.ext.get(channel);
if (f)
{
res = ServerInstance->OnCheckExemption(user,channel,"nickflood");
if (res == MOD_RES_ALLOW)
return;
/* moved this here to avoid incrementing the counter for nick
* changes that are denied for some other reason (bans, +N, etc.)
* per bug #874.
*/
f->addnick();
}
}
return;
}
~ModuleNickFlood()
{
}
Version GetVersion()
{
return Version("Channel mode F - nick flood protection", VF_VENDOR);
}
};
MODULE_INIT(ModuleNickFlood)
