Add a vendor tag that shows the IP/real host to privileged users.

This is a non-official implementation of UnrealIRCd's userhost-tag and
userip-tag modules.
See discussion at: ircv3/ircv3-specifications#418

3.0/m_tag_iphost.cpp

@@ -0,0 +1,121 @@
+/*
+ * InspIRCd -- Internet Relay Chat Daemon
+ *
+ *   Copyright (C) 2020 Matt Schatz <[email protected]>
+ *
+ * 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/>.
+ */
+
+/// $ModAuthor: genius3000
+/// $ModAuthorMail: [email protected]
+/// $ModConfig: <iphost accounts="sally22 BillBob someoneElse"> <class privs="users/iphost">
+/// $ModDepends: core 3
+/// $ModDesc: Provides message tags for showing the IP address and real host to a privileged user.
+// These tags will only be sent to a privileged user if they have enabled the 'message-tags' capability.
+// Privileged users are set via an oper class privilege or a space separated list of services accounts.
+// Note: m_ircv3_ctctags is required for this module to provide anything.
+// Note: m_services_account is required for the services account method to be used.
+
+
+#include "inspircd.h"
+#include "modules/account.h"
+#include "modules/ctctags.h"
+
+class TagIPHost : public ClientProtocol::MessageTagProvider
+{
+ private:
+	CTCTags::CapReference ctctagcap;
+
+ public:
+	std::vector<std::string> accounts;
+
+	TagIPHost(Module* mod)
+		: ClientProtocol::MessageTagProvider(mod)
+		, ctctagcap(mod)
+	{
+	}
+
+	void OnPopulateTags(ClientProtocol::Message& msg) CXX11_OVERRIDE
+	{
+		User* const user = msg.GetSourceUser();
+		if (user && !IS_SERVER(user) && !user->server->IsULine())
+		{
+			msg.AddTag("inspircd.org/ip", this, user->GetIPString());
+			msg.AddTag("inspircd.org/realhost", this, user->GetHost(true));
+		}
+	}
+
+	ModResult OnProcessTag(User*, const std::string&, std::string&) CXX11_OVERRIDE
+	{
+		// Disallow anyone from sending this tag themselves.
+		return MOD_RES_DENY;
+	}
+
+	bool ShouldSendTag(LocalUser* user, const ClientProtocol::MessageTagData&) CXX11_OVERRIDE
+	{
+		if (!ctctagcap.get(user))
+			return false;
+
+		if (user->HasPrivPermission("users/iphost"))
+			return true;
+
+		if (accounts.empty())
+			return false;
+
+		const AccountExtItem* accountext = GetAccountExtItem();
+		const std::string* account = accountext ? accountext->get(user) : NULL;
+		if (!account)
+			return false;
+
+		for (std::vector<std::string>::const_iterator i = accounts.begin(); i != accounts.end(); ++i)
+		{
+			if (irc::equals(*account, *i))
+				return true;
+		}
+
+		return false;
+	}
+};
+
+class ModuleTagIPHost : public Module
+{
+ private:
+	TagIPHost iphost;
+
+ public:
+	ModuleTagIPHost()
+		: iphost(this)
+	{
+	}
+
+	void ReadConfig(ConfigStatus&) CXX11_OVERRIDE
+	{
+		std::vector<std::string> newaccounts;
+
+		ConfigTag* tag = ServerInstance->Config->ConfValue("iphost");
+		const std::string accounts = tag->getString("accounts");
+
+		irc::spacesepstream ss(accounts);
+		for (std::string token; ss.GetToken(token); )
+			newaccounts.push_back(token);
+
+		iphost.accounts.swap(newaccounts);
+	}
+
+	Version GetVersion() CXX11_OVERRIDE
+	{
+		return Version("Provides message tags for showing the IP address and real host to a privileged user.");
+	}
+};
+
+MODULE_INIT(ModuleTagIPHost)