/*
* InspIRCd -- Internet Relay Chat Daemon
*
* Copyright (C) 2019 Robby <robby@chatbelgie.be>
* Copyright (C) 2018-2021 Sadie Powell <sadie@witchery.services>
*
* 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"
#include "modules/exemption.h"
enum AntiCapsMethod
{
ACM_BAN,
ACM_BLOCK,
ACM_MUTE,
ACM_KICK,
ACM_KICK_BAN
};
class AntiCapsSettings
{
public:
const AntiCapsMethod method;
const uint16_t minlen;
const uint8_t percent;
AntiCapsSettings(const AntiCapsMethod& Method, const uint16_t& MinLen, const uint8_t& Percent)
: method(Method)
, minlen(MinLen)
, percent(Percent)
{
}
};
class AntiCapsMode : public ParamMode<AntiCapsMode, SimpleExtItem<AntiCapsSettings> >
{
private:
bool ParseMethod(irc::sepstream& stream, AntiCapsMethod& method)
{
std::string methodstr;
if (!stream.GetToken(methodstr))
return false;
if (irc::equals(methodstr, "ban"))
method = ACM_BAN;
else if (irc::equals(methodstr, "block"))
method = ACM_BLOCK;
else if (irc::equals(methodstr, "mute"))
method = ACM_MUTE;
else if (irc::equals(methodstr, "kick"))
method = ACM_KICK;
else if (irc::equals(methodstr, "kickban"))
method = ACM_KICK_BAN;
else
return false;
return true;
}
bool ParseMinimumLength(irc::sepstream& stream, uint16_t& minlen)
{
std::string minlenstr;
if (!stream.GetToken(minlenstr))
return false;
uint16_t result = ConvToNum<uint16_t>(minlenstr);
if (result < 1 || result > ServerInstance->Config->Limits.MaxLine)
return false;
minlen = result;
return true;
}
bool ParsePercent(irc::sepstream& stream, uint8_t& percent)
{
std::string percentstr;
if (!stream.GetToken(percentstr))
return false;
uint8_t result = ConvToNum<uint8_t>(percentstr);
if (result < 1 || result > 100)
return false;
percent = result;
return true;
}
public:
AntiCapsMode(Module* Creator)
: ParamMode<AntiCapsMode, SimpleExtItem<AntiCapsSettings> >(Creator, "anticaps", 'B')
{
syntax = "{ban|block|mute|kick|kickban}:<minlen>:<percent>";
}
ModeAction OnSet(User* source, Channel* channel, std::string& parameter) CXX11_OVERRIDE
{
irc::sepstream stream(parameter, ':');
AntiCapsMethod method;
uint16_t minlen;
uint8_t percent;
// Attempt to parse the method.
if (!ParseMethod(stream, method) || !ParseMinimumLength(stream, minlen) || !ParsePercent(stream, percent))
{
source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter));
return MODEACTION_DENY;
}
ext.set(channel, new AntiCapsSettings(method, minlen, percent));
return MODEACTION_ALLOW;
}
void SerializeParam(Channel* chan, const AntiCapsSettings* acs, std::string& out)
{
switch (acs->method)
{
case ACM_BAN:
out.append("ban");
break;
case ACM_BLOCK:
out.append("block");
break;
case ACM_MUTE:
out.append("mute");
break;
case ACM_KICK:
out.append("kick");
break;
case ACM_KICK_BAN:
out.append("kickban");
break;
default:
out.append("unknown~");
out.append(ConvToStr(acs->method));
break;
}
out.push_back(':');
out.append(ConvToStr(acs->minlen));
out.push_back(':');
out.append(ConvNumeric(acs->percent));
}
};
class ModuleAntiCaps : public Module
{
private:
CheckExemption::EventProvider exemptionprov;
std::bitset<UCHAR_MAX + 1> uppercase;
std::bitset<UCHAR_MAX + 1> lowercase;
AntiCapsMode mode;
void CreateBan(Channel* channel, User* user, bool mute)
{
std::string banmask(mute ? "m:" : "");
banmask.append("*!*@");
banmask.append(user->GetDisplayedHost());
Modes::ChangeList changelist;
changelist.push_add(ServerInstance->Modes->FindMode('b', MODETYPE_CHANNEL), banmask);
ServerInstance->Modes->Process(ServerInstance->FakeClient, channel, NULL, changelist);
}
void InformUser(Channel* channel, User* user, const std::string& message)
{
user->WriteNumeric(Numerics::CannotSendTo(channel, message + " and was blocked."));
}
public:
ModuleAntiCaps()
: exemptionprov(this)
, mode(this)
{
}
void ReadConfig(ConfigStatus&) CXX11_OVERRIDE
{
ConfigTag* tag = ServerInstance->Config->ConfValue("anticaps");
uppercase.reset();
const std::string upper = tag->getString("uppercase", "ABCDEFGHIJKLMNOPQRSTUVWXYZ", 1);
for (std::string::const_iterator iter = upper.begin(); iter != upper.end(); ++iter)
uppercase.set(static_cast<unsigned char>(*iter));
lowercase.reset();
const std::string lower = tag->getString("lowercase", "abcdefghijklmnopqrstuvwxyz");
for (std::string::const_iterator iter = lower.begin(); iter != lower.end(); ++iter)
lowercase.set(static_cast<unsigned char>(*iter));
}
ModResult OnUserPreMessage(User* user, const MessageTarget& target, MessageDetails& details) CXX11_OVERRIDE
{
// We only want to operate on messages from local users.
if (!IS_LOCAL(user))
return MOD_RES_PASSTHRU;
// The mode can only be applied to channels.
if (target.type != MessageTarget::TYPE_CHANNEL)
return MOD_RES_PASSTHRU;
// We only act if the channel has the mode set.
Channel* channel = target.Get<Channel>();
if (!channel->IsModeSet(&mode))
return MOD_RES_PASSTHRU;
// If the user is exempt from anticaps then we don't need
// to do anything else.
ModResult result = CheckExemption::Call(exemptionprov, user, channel, "anticaps");
if (result == MOD_RES_ALLOW)
return MOD_RES_PASSTHRU;
// If the message is a CTCP then we skip it unless it is
// an ACTION in which case we just check against the body.
std::string ctcpname;
std::string msgbody(details.text);
if (details.IsCTCP(ctcpname, msgbody))
{
// If the CTCP is not an action then skip it.
if (!irc::equals(ctcpname, "ACTION"))
return MOD_RES_PASSTHRU;
}
// Retrieve the anticaps config. This should never be
// null but its better to be safe than sorry.
AntiCapsSettings* config = mode.ext.get(channel);
if (!config)
return MOD_RES_PASSTHRU;
// If the message is shorter than the minimum length then
// we don't need to do anything else.
size_t length = msgbody.length();
if (length < config->minlen)
return MOD_RES_PASSTHRU;
// Count the characters to see how many upper case and
// ignored (non upper or lower) characters there are.
size_t upper = 0;
for (std::string::const_iterator iter = msgbody.begin(); iter != msgbody.end(); ++iter)
{
unsigned char chr = static_cast<unsigned char>(*iter);
if (uppercase.test(chr))
upper += 1;
else if (!lowercase.test(chr))
length -= 1;
}
// If the message was entirely symbols then the message
// can't contain any upper case letters.
if (length == 0)
return MOD_RES_PASSTHRU;
// Calculate the percentage.
double percent = round((upper * 100) / length);
if (percent < config->percent)
return MOD_RES_PASSTHRU;
const std::string message = InspIRCd::Format("Your message exceeded the %d%% upper case character threshold for %s",
config->percent, channel->name.c_str());
switch (config->method)
{
case ACM_BAN:
InformUser(channel, user, message);
CreateBan(channel, user, false);
break;
case ACM_BLOCK:
InformUser(channel, user, message);
break;
case ACM_MUTE:
InformUser(channel, user, message);
CreateBan(channel, user, true);
break;
case ACM_KICK:
channel->KickUser(ServerInstance->FakeClient, user, message);
break;
case ACM_KICK_BAN:
CreateBan(channel, user, false);
channel->KickUser(ServerInstance->FakeClient, user, message);
break;
}
return MOD_RES_DENY;
}
Version GetVersion() CXX11_OVERRIDE
{
return Version("Adds channel mode B (anticaps) which allows channels to block messages which are excessively capitalised.", VF_COMMON|VF_VENDOR);
}
};
MODULE_INIT(ModuleAntiCaps)
