Shuffle the modules about a bit.

1 files changed, 501 insertions, 0 deletions

diff --git a/modules/cap.cpp b/modules/cap.cpp
new file mode 100644
index 000000000..87eb8f794
--- /dev/null
+++ b/modules/cap.cpp
@@ -0,0 +1,501 @@
+/*
+ * InspIRCd -- Internet Relay Chat Daemon
+ *
+ *   Copyright (C) 2018-2023 Sadie Powell <sadie@witchery.services>
+ *   Copyright (C) 2015-2016, 2018 Attila Molnar <attilamolnar@hush.com>
+ *
+ * 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/reload.h"
+#include "modules/cap.h"
+#include "utility/string.h"
+
+enum
+{
+	// From IRCv3 capability-negotiation-3.1.
+	ERR_INVALIDCAPCMD = 410
+};
+
+namespace Cap
+{
+	class ManagerImpl;
+}
+
+static Cap::ManagerImpl* managerimpl;
+
+class Cap::ManagerImpl final
+	: public Cap::Manager
+	, public ReloadModule::EventListener
+{
+	/** Stores the cap state of a module being reloaded
+	 */
+	struct CapModData final
+	{
+		struct Data final
+		{
+			std::string name;
+			std::vector<std::string> users;
+
+			Data(Capability* cap)
+				: name(cap->GetName())
+			{
+			}
+		};
+		std::vector<Data> caps;
+	};
+
+	typedef insp::flat_map<std::string, Capability*, irc::insensitive_swo> CapMap;
+
+	ExtItem capext;
+	CapMap caps;
+	Events::ModuleEventProvider& evprov;
+
+	static bool CanRequest(LocalUser* user, Ext usercaps, Capability* cap, bool adding)
+	{
+		const bool hascap = ((usercaps & cap->GetMask()) != 0);
+		if (hascap == adding)
+			return true;
+
+		return cap->OnRequest(user, adding);
+	}
+
+	Capability::Bit AllocateBit() const
+	{
+		Capability::Bit used = 0;
+		for (const auto& [_, cap] : caps)
+			used |= cap->GetMask();
+
+		for (size_t i = 0; i < MAX_CAPS; i++)
+		{
+			Capability::Bit bit = (static_cast<Capability::Bit>(1) << i);
+			if (!(used & bit))
+				return bit;
+		}
+		throw ModuleException(creator, "Too many caps");
+	}
+
+	void OnReloadModuleSave(Module* mod, ReloadModule::CustomData& cd) override
+	{
+		ServerInstance->Logs.Debug(MODNAME, "OnReloadModuleSave()");
+		if (mod == creator)
+			return;
+
+		auto* capmoddata = new CapModData();
+		cd.add(this, capmoddata);
+
+		for (const auto& [_, cap] : caps)
+		{
+			// Only save users of caps that belong to the module being reloaded
+			if (cap->creator != mod)
+				continue;
+
+			ServerInstance->Logs.Debug(MODNAME, "Module being reloaded implements cap {}, saving cap users", cap->GetName());
+			capmoddata->caps.emplace_back(cap);
+			CapModData::Data& capdata = capmoddata->caps.back();
+
+			// Populate list with uuids of users who are using the cap
+			for (auto* user : ServerInstance->Users.GetLocalUsers())
+			{
+				if (cap->IsEnabled(user))
+					capdata.users.push_back(user->uuid);
+			}
+		}
+	}
+
+	void OnReloadModuleRestore(Module* mod, void* data) override
+	{
+		CapModData* capmoddata = static_cast<CapModData*>(data);
+		for (const auto& capdata : capmoddata->caps)
+		{
+			Capability* cap = ManagerImpl::Find(capdata.name);
+			if (!cap)
+			{
+				ServerInstance->Logs.Debug(MODNAME, "Cap {} is no longer available after reload", capdata.name);
+				continue;
+			}
+
+			// Set back the cap for all users who were using it before the reload
+			for (const auto& uuid : capdata.users)
+			{
+				auto* user = ServerInstance->Users.FindUUID(uuid);
+				if (!user)
+				{
+					ServerInstance->Logs.Debug(MODNAME, "User {} is gone when trying to restore cap {}", uuid, capdata.name);
+					continue;
+				}
+
+				cap->Set(user, true);
+			}
+		}
+		delete capmoddata;
+	}
+
+public:
+	ManagerImpl(Module* mod, Events::ModuleEventProvider& evprovref)
+		: Cap::Manager(mod)
+		, ReloadModule::EventListener(mod)
+		, capext(mod)
+		, evprov(evprovref)
+	{
+		managerimpl = this;
+	}
+
+	~ManagerImpl() override
+	{
+		for (const auto& [_, cap] : caps)
+			cap->Unregister();
+	}
+
+	void AddCap(Cap::Capability* cap) override
+	{
+		// No-op if the cap is already registered.
+		// This allows modules to call SetActive() on a cap without checking if it's active first.
+		if (cap->IsRegistered())
+			return;
+
+		ServerInstance->Logs.Debug(MODNAME, "Registering cap {}", cap->GetName());
+		cap->bit = AllocateBit();
+		cap->extitem = &capext;
+		caps.emplace(cap->GetName(), cap);
+		ServerInstance->Modules.AddReferent("cap/" + cap->GetName(), cap);
+
+		evprov.Call(&Cap::EventListener::OnCapAddDel, cap, true);
+	}
+
+	void DelCap(Cap::Capability* cap) override
+	{
+		// No-op if the cap is not registered, see AddCap() above
+		if (!cap->IsRegistered())
+			return;
+
+		ServerInstance->Logs.Debug(MODNAME, "Unregistering cap {}", cap->GetName());
+
+		// Fire the event first so modules can still see who is using the cap which is being unregistered
+		evprov.Call(&Cap::EventListener::OnCapAddDel, cap, false);
+
+		// Turn off the cap for all users
+		for (auto* user : ServerInstance->Users.GetLocalUsers())
+			cap->Set(user, false);
+
+		ServerInstance->Modules.DelReferent(cap);
+		cap->Unregister();
+		caps.erase(cap->GetName());
+	}
+
+	Capability* Find(const std::string& capname) const override
+	{
+		CapMap::const_iterator it = caps.find(capname);
+		if (it != caps.end())
+			return it->second;
+		return nullptr;
+	}
+
+	void NotifyValueChange(Capability* cap) override
+	{
+		ServerInstance->Logs.Debug(MODNAME, "Cap {} changed value", cap->GetName());
+		evprov.Call(&Cap::EventListener::OnCapValueChange, cap);
+	}
+
+	Protocol GetProtocol(LocalUser* user) const
+	{
+		return ((capext.Get(user) & CAP_302_BIT) ? CAP_302 : CAP_LEGACY);
+	}
+
+	void Set302Protocol(LocalUser* user)
+	{
+		capext.Set(user, capext.Get(user) | CAP_302_BIT);
+	}
+
+	bool HandleReq(LocalUser* user, const std::string& reqlist)
+	{
+		Ext usercaps = capext.Get(user);
+		irc::spacesepstream ss(reqlist);
+		for (std::string capname; ss.GetToken(capname); )
+		{
+			bool remove = (capname[0] == '-');
+			if (remove)
+				capname.erase(capname.begin());
+
+			Capability* cap = ManagerImpl::Find(capname);
+			if ((!cap) || (!CanRequest(user, usercaps, cap, !remove)))
+				return false;
+
+			if (remove)
+				usercaps = cap->DelFromMask(usercaps);
+			else
+				usercaps = cap->AddToMask(usercaps);
+		}
+
+		capext.Set(user, usercaps);
+		return true;
+	}
+
+	void HandleList(std::vector<std::string>& out, LocalUser* user, bool show_all, bool show_values, bool minus_prefix = false) const
+	{
+		Ext show_caps = (show_all ? ~0 : capext.Get(user));
+
+		for (const auto& [_, cap] : caps)
+		{
+			if (!(show_caps & cap->GetMask()))
+				continue;
+
+			if ((show_all) && (!cap->OnList(user)))
+				continue;
+
+			std::string token;
+			if (minus_prefix)
+				token.push_back('-');
+			token.append(cap->GetName());
+
+			if (show_values)
+			{
+				const std::string* capvalue = cap->GetValue(user);
+				if ((capvalue) && (!capvalue->empty()) && (capvalue->find(' ') == std::string::npos))
+				{
+					token.push_back('=');
+					token.append(*capvalue, 0, MAX_VALUE_LENGTH);
+				}
+			}
+			out.push_back(token);
+		}
+	}
+
+	void HandleClear(LocalUser* user, std::vector<std::string>& result)
+	{
+		HandleList(result, user, false, false, true);
+		capext.Unset(user);
+	}
+};
+
+namespace
+{
+	std::string SerializeCaps(const Extensible* container, bool human)
+	{
+		// XXX: Cast away the const because IS_LOCAL() doesn't handle it
+		LocalUser* user = IS_LOCAL(const_cast<User*>(static_cast<const User*>(container)));
+		if (!user)
+			return {};
+
+		// List requested caps
+		std::vector<std::string> result;
+		managerimpl->HandleList(result, user, false, false);
+
+		// Serialize cap protocol version. If building a human-readable string append a
+		// new token, otherwise append only a single character indicating the version.
+		std::string version;
+		if (human)
+			version.append("capversion=3.");
+		switch (managerimpl->GetProtocol(user))
+		{
+			case Cap::CAP_302:
+				version.push_back('2');
+				break;
+			default:
+				version.push_back('1');
+				break;
+		}
+		result.push_back(version);
+
+		return insp::join(result, ' ');
+	}
+}
+
+Cap::ExtItem::ExtItem(Module* mod)
+	: IntExtItem(mod, "caps", ExtensionType::USER)
+{
+}
+
+std::string Cap::ExtItem::ToHuman(const Extensible* container, void* item) const noexcept
+{
+	return SerializeCaps(container, true);
+}
+
+std::string Cap::ExtItem::ToInternal(const Extensible* container, void* item) const noexcept
+{
+	return SerializeCaps(container, false);
+}
+
+void Cap::ExtItem::FromInternal(Extensible* container, const std::string& value) noexcept
+{
+	if (container->extype != this->extype)
+		return;
+
+	LocalUser* user = IS_LOCAL(static_cast<User*>(container));
+	if (!user)
+		return; // Can't happen
+
+	// Process the cap protocol version which is a single character at the end of the serialized string
+	if (value.back() == '2')
+		managerimpl->Set302Protocol(user);
+
+	// Remove the version indicator from the string passed to HandleReq
+	std::string caplist(value, 0, value.size()-1);
+	managerimpl->HandleReq(user, caplist);
+}
+
+class CapMessage final
+	: public Cap::MessageBase
+{
+public:
+	CapMessage(LocalUser* user, const std::string& subcmd, const std::string& result, bool asterisk)
+		: Cap::MessageBase(subcmd)
+	{
+		SetUser(user);
+		if (asterisk)
+			PushParam("*");
+		PushParamRef(result);
+	}
+};
+
+class CommandCap final
+	: public SplitCommand
+{
+private:
+	Events::ModuleEventProvider evprov;
+	Cap::ManagerImpl manager;
+	ClientProtocol::EventProvider protoevprov;
+
+	void DisplayResult(LocalUser* user, const std::string& subcmd, const std::vector<std::string>& result, bool asterisk)
+	{
+		size_t maxline = ServerInstance->Config->Limits.MaxLine - ServerInstance->Config->ServerName.size() - user->nick.length() - subcmd.length() - 11;
+		std::string line;
+		for (const auto& cap : result)
+		{
+			if (line.length() + cap.length() < maxline)
+			{
+				line.append(cap);
+				line.push_back(' ');
+			}
+			else
+			{
+				DisplaySingleResult(user, subcmd, line, asterisk);
+				line.clear();
+			}
+		}
+		DisplaySingleResult(user, subcmd, line, false);
+	}
+
+	void DisplaySingleResult(LocalUser* user, const std::string& subcmd, const std::string& result, bool asterisk)
+	{
+		CapMessage msg(user, subcmd, result, asterisk);
+		ClientProtocol::Event ev(protoevprov, msg);
+		user->Send(ev);
+	}
+
+public:
+	BoolExtItem holdext;
+
+	CommandCap(Module* mod)
+		: SplitCommand(mod, "CAP", 1)
+		, evprov(mod, "event/cap")
+		, manager(mod, evprov)
+		, protoevprov(mod, name)
+		, holdext(mod, "cap-hold", ExtensionType::USER)
+	{
+		works_before_reg = true;
+	}
+
+	CmdResult HandleLocal(LocalUser* user, const Params& parameters) override
+	{
+		if (!user->IsFullyConnected())
+			holdext.Set(user);
+
+		const std::string& subcommand = parameters[0];
+		if (irc::equals(subcommand, "REQ"))
+		{
+			if (parameters.size() < 2)
+				return CmdResult::FAILURE;
+
+			const std::string replysubcmd = (manager.HandleReq(user, parameters[1]) ? "ACK" : "NAK");
+			DisplaySingleResult(user, replysubcmd, parameters[1], false);
+		}
+		else if (irc::equals(subcommand, "END"))
+		{
+			holdext.Unset(user);
+		}
+		else if (irc::equals(subcommand, "LS") || irc::equals(subcommand, "LIST"))
+		{
+			Cap::Protocol capversion = Cap::CAP_LEGACY;
+			const bool is_ls = (subcommand.length() == 2);
+			if ((is_ls) && (parameters.size() > 1))
+			{
+				unsigned int version = ConvToNum<unsigned int>(parameters[1]);
+				if (version >= 302)
+				{
+					capversion = Cap::CAP_302;
+					manager.Set302Protocol(user);
+				}
+			}
+
+			std::vector<std::string> result;
+			// Show values only if supports v3.2 and doing LS
+			manager.HandleList(result, user, is_ls, ((is_ls) && (capversion != Cap::CAP_LEGACY)));
+			DisplayResult(user, subcommand, result, (capversion != Cap::CAP_LEGACY));
+		}
+		else if (irc::equals(subcommand, "CLEAR") && (manager.GetProtocol(user) == Cap::CAP_LEGACY))
+		{
+			std::vector<std::string> result;
+			manager.HandleClear(user, result);
+			DisplayResult(user, "ACK", result, false);
+		}
+		else
+		{
+			user->WriteNumeric(ERR_INVALIDCAPCMD, subcommand.empty() ? "*" : subcommand, "Invalid CAP subcommand");
+			return CmdResult::FAILURE;
+		}
+
+		return CmdResult::SUCCESS;
+	}
+};
+
+class PoisonCap final
+	: public Cap::Capability
+{
+public:
+	PoisonCap(Module* mod)
+		: Cap::Capability(mod, "inspircd.org/poison")
+	{
+	}
+
+	bool OnRequest(LocalUser* user, bool adding) override
+	{
+		// Reject the attempt to enable this capability.
+		return false;
+	}
+};
+
+class ModuleCap final
+	: public Module
+{
+private:
+	CommandCap cmd;
+	PoisonCap poisoncap;
+
+public:
+	ModuleCap()
+		: Module(VF_VENDOR, "Provides support for the IRCv3 Client Capability Negotiation extension.")
+		, cmd(this)
+		, poisoncap(this)
+	{
+	}
+
+	ModResult OnCheckReady(LocalUser* user) override
+	{
+		return (cmd.holdext.Get(user) ? MOD_RES_DENY : MOD_RES_PASSTHRU);
+	}
+};
+
+MODULE_INIT(ModuleCap)