Add m_insp_joinpartspam - First release.

Implement better support for the InspIRCd 2.0 Extras
m_joinpartspam. Verify cycle, duration, and block time
parameters; and disallow channel redirects when using
ChanServ MODE for this custom mode.

README.md

@@ -32,6 +32,12 @@ To send a notice (via email and/or memo) to a user that their registered nicknam
 channel is soon to expire and/or expired. Fully configurable with what to send for and
 how to send the notices, when to send the pre-expiry notices, and the messages sent.
 
+### m_insp_joinpartspam
+Adds (almost) proper support for the InspIRCd 2.0 Extras module m_joinpartspam. Use
+this module to ensure the mode is not abusable through ChanServ MODE. Channel redirects
+with this mode are disallowed here, as we can't verify the parameter.
+Requires a restart to load, can be reloaded live though.
+
 ### [m_xlinetoakill](https://modules.anope.org/index.php?page=view&id=285 "View module on the Anope Module Site")
 Syncs X-Lines (G, Z, R) from the uplink IRCd to the AKILL list. Works on server sync
 and as X-Lines are added or removed. Requires OperServ, AKILL, and the InspIRCd 2.0

m_insp_joinpartspam.cpp

@@ -0,0 +1,104 @@
+/*
+ * Support for InspIRCd 2.0 Extras m_joinpartspam.
+ *
+ * (C) 2019 - Matt Schatz (genius3000@g3k.solutions)
+ * Please refer to the GPL License in use by Anope at:
+ * https://github.com/anope/anope/blob/master/docs/COPYING
+ *
+ * Provides the required logic for the mode to be mostly
+ * functional with ChanServ MODE but not abusable.
+ *
+ * Configuration to put into your modules config:
+module { name = "m_insp_joinpartspam" }
+ *
+ */
+
+#include "module.h"
+
+
+static Module *me;
+
+class ChannelModeJoinPartSpam : public ChannelModeParam
+{
+	bool ParseCycles(sepstream &stream) const
+	{
+		Anope::string strcycles;
+		if (!stream.GetToken(strcycles))
+			return false;
+
+		int result = convertTo<int>(strcycles);
+		if (result < 2 || result > 20)
+			return false;
+
+		return true;
+	}
+
+	bool ParseSeconds(sepstream &stream) const
+	{
+		Anope::string strseconds;
+		if (!stream.GetToken(strseconds))
+			return false;
+
+		int result = convertTo<int>(strseconds);
+		if (result < 1 || result > 43200)
+			return false;
+
+		return true;
+	}
+
+ public:
+	ChannelModeJoinPartSpam(const Anope::string &modename, const char modechar) : ChannelModeParam(modename, modechar, true) { }
+
+	bool IsValid(Anope::string &value) const anope_override
+	{
+		sepstream stream(value, ':');
+
+		if (!ParseCycles(stream))
+			return false;
+		// This checks duration first then block time.
+		if (!ParseSeconds(stream) || !ParseSeconds(stream))
+			return false;
+		// Disallow any redirect from here, we can't verify the parameter.
+		if (!stream.StreamEnd())
+			return false;
+
+		return true;
+	}
+};
+
+class InspJoinPartSpam : public Module
+{
+	const Anope::string modename;
+	const char modechar;
+
+ public:
+	InspJoinPartSpam(const Anope::string &modname, const Anope::string &creator)
+		: Module(modname, creator, THIRD)
+		, modename("JOINPARTSPAM")
+		, modechar('x')
+	{
+		if (Anope::VersionMajor() != 2 || Anope::VersionMinor() != 0)
+			throw ModuleException("Requires version 2.0.x of Anope.");
+
+		if (!ModuleManager::FindModule("inspircd20"))
+			throw ModuleException("This module only works with the InspIRCd 2.0 protocol.");
+
+		ChannelMode *cm = ModeManager::FindChannelModeByChar(modechar);
+		if (cm)
+			throw ModuleException("A channel mode with character '" + Anope::string(modechar) + "' already exists.");
+
+		this->SetAuthor("genius3000");
+		this->SetVersion("1.0.0");
+		me = this;
+		ModeManager::AddChannelMode(new ChannelModeJoinPartSpam(modename, modechar));
+	}
+
+	~InspJoinPartSpam()
+	{
+		ChannelMode *cm = ModeManager::FindChannelModeByChar(modechar);
+		if (cm)
+			ModeManager::RemoveChannelMode(cm);
+	}
+};
+
+MODULE_INIT(InspJoinPartSpam)