Shuffle the modules about a bit.

1 files changed, 298 insertions, 0 deletions

diff --git a/modules/anticaps.cpp b/modules/anticaps.cpp
new file mode 100644
index 000000000..bc396600c
--- /dev/null
+++ b/modules/anticaps.cpp
@@ -0,0 +1,298 @@
+/*
+ * InspIRCd -- Internet Relay Chat Daemon
+ *
+ *   Copyright (C) 2018-2024 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 <cmath>
+
+#include "inspircd.h"
+#include "extension.h"
+#include "modules/exemption.h"
+#include "numerichelper.h"
+
+enum class AntiCapsMethod
+	: uint8_t
+{
+	BAN,
+	BLOCK,
+	MUTE,
+	KICK,
+	KICK_BAN,
+};
+
+class AntiCapsSettings final
+{
+private:
+	bool ParseMethod(irc::sepstream& stream)
+	{
+		std::string methodstr;
+		if (!stream.GetToken(methodstr))
+			return false;
+
+		if (irc::equals(methodstr, "ban"))
+			method = AntiCapsMethod::BAN;
+		else if (irc::equals(methodstr, "block"))
+			method = AntiCapsMethod::BLOCK;
+		else if (irc::equals(methodstr, "mute"))
+			method = AntiCapsMethod::MUTE;
+		else if (irc::equals(methodstr, "kick"))
+			method = AntiCapsMethod::KICK;
+		else if (irc::equals(methodstr, "kickban"))
+			method = AntiCapsMethod::KICK_BAN;
+		else
+			return false;
+
+		return true;
+	}
+
+	bool ParseMinimumLength(irc::sepstream& stream)
+	{
+		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)
+	{
+		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:
+	AntiCapsMethod method = AntiCapsMethod::BLOCK;
+	uint16_t minlen = 0;
+	uint8_t percent = 0;
+
+	bool Parse(const std::string& str)
+	{
+		irc::sepstream stream(str, ':');
+		return ParseMethod(stream) && ParseMinimumLength(stream) && ParsePercent(stream);
+	}
+};
+
+class AntiCapsMode final
+	: public ParamMode<AntiCapsMode, SimpleExtItem<AntiCapsSettings>>
+{
+public:
+	AntiCapsMode(Module* Creator)
+		: ParamMode<AntiCapsMode, SimpleExtItem<AntiCapsSettings>>(Creator, "anticaps", 'B')
+	{
+		syntax = "{ban|block|mute|kick|kickban}:<minlen>:<percent>";
+	}
+
+	bool OnSet(User* source, Channel* channel, std::string& parameter) override
+	{
+		AntiCapsSettings settings;
+		if (!settings.Parse(parameter))
+		{
+			source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter));
+			return false;
+		}
+
+		ext.Set(channel, settings);
+		return true;
+	}
+
+	void SerializeParam(Channel* chan, const AntiCapsSettings* acs, std::string& out)
+	{
+		switch (acs->method)
+		{
+			case AntiCapsMethod::BAN:
+				out.append("ban");
+				break;
+			case AntiCapsMethod::BLOCK:
+				out.append("block");
+				break;
+			case AntiCapsMethod::MUTE:
+				out.append("mute");
+				break;
+			case AntiCapsMethod::KICK:
+				out.append("kick");
+				break;
+			case AntiCapsMethod::KICK_BAN:
+				out.append("kickban");
+				break;
+		}
+		out.push_back(':');
+		out.append(ConvToStr(acs->minlen));
+		out.push_back(':');
+		out.append(ConvToStr<uint16_t>(acs->percent));
+	}
+};
+
+class ModuleAntiCaps final
+	: public Module
+{
+private:
+	ChanModeReference banmode;
+	CheckExemption::EventProvider exemptionprov;
+	CharState uppercase;
+	CharState lowercase;
+	AntiCapsMode mode;
+
+	void CreateBan(Channel* channel, User* user, bool mute)
+	{
+		std::string banmask(mute ? "m:*!" : "*!");
+		banmask.append(user->GetBanUser(false));
+		banmask.append("@");
+		banmask.append(user->GetDisplayedHost());
+
+		Modes::ChangeList changelist;
+		changelist.push_add(*banmode, banmask);
+		ServerInstance->Modes.Process(ServerInstance->FakeClient, channel, nullptr, changelist);
+	}
+
+	static void InformUser(Channel* channel, User* user, const std::string& message)
+	{
+		user->WriteNumeric(Numerics::CannotSendTo(channel, message + " and was blocked."));
+	}
+
+public:
+	ModuleAntiCaps()
+		: Module(VF_VENDOR | VF_COMMON, "Adds channel mode B (anticaps) which allows channels to block messages which are excessively capitalised.")
+		, banmode(this, "ban")
+		, exemptionprov(this)
+		, mode(this)
+	{
+	}
+
+	void ReadConfig(ConfigStatus&) override
+	{
+		const auto& tag = ServerInstance->Config->ConfValue("anticaps");
+
+		uppercase.reset();
+		for (const auto chr : tag->getString("uppercase", "ABCDEFGHIJKLMNOPQRSTUVWXYZ", 1))
+			uppercase.set(static_cast<unsigned char>(chr));
+
+		lowercase.reset();
+		for (const auto chr : tag->getString("lowercase", "abcdefghijklmnopqrstuvwxyz", 1))
+			lowercase.set(static_cast<unsigned char>(chr));
+	}
+
+	ModResult OnUserPreMessage(User* user, MessageTarget& target, MessageDetails& details) 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.
+		auto* 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 = exemptionprov.Check(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_view ctcpname;
+		std::string_view 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 (const auto chr : msgbody)
+		{
+			if (uppercase.test(static_cast<unsigned char>(chr)))
+				upper += 1;
+			else if (!lowercase.test(static_cast<unsigned char>(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 = fmt::format("Your message exceeded the {}% upper case character threshold for {}",
+			config->percent, channel->name);
+
+		switch (config->method)
+		{
+			case AntiCapsMethod::BAN:
+				InformUser(channel, user, message);
+				CreateBan(channel, user, false);
+				break;
+
+			case AntiCapsMethod::BLOCK:
+				InformUser(channel, user, message);
+				break;
+
+			case AntiCapsMethod::MUTE:
+				InformUser(channel, user, message);
+				CreateBan(channel, user, true);
+				break;
+
+			case AntiCapsMethod::KICK:
+				channel->KickUser(ServerInstance->FakeClient, user, message);
+				break;
+
+			case AntiCapsMethod::KICK_BAN:
+				CreateBan(channel, user, false);
+				channel->KickUser(ServerInstance->FakeClient, user, message);
+				break;
+		}
+		return MOD_RES_DENY;
+	}
+};
+
+MODULE_INIT(ModuleAntiCaps)