Merge branch 'master+cap'

12 files changed, 1088 insertions, 43 deletions

diff --git a/docs/conf/modules.conf.example b/docs/conf/modules.conf.example
index 055bdc0b4..52a8f5eeb 100644
--- a/docs/conf/modules.conf.example
+++ b/docs/conf/modules.conf.example
@@ -878,6 +878,9 @@
 # hostcycle: If loaded, when a user gets a host or ident set, it will
 # cycle them in all their channels. If not loaded it will simply change
 # their host/ident without cycling them.
+# This module is compatible with the ircv3_chghost module. Clients
+# supporting the chghost extension will get the chghost message instead
+# of seeing a host cycle.
 #<module name="hostcycle">
 
 #-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#
@@ -966,6 +969,19 @@
 #<ircv3 accountnotify="on" awaynotify="on" extendedjoin="on">
 
 #-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#
+# IRCv3 cap-notify module: Provides the cap-notify IRCv3.2 extension.
+# Required for IRCv3.2 conformance.
+#<module name="ircv3_capnotify">
+
+#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#
+# IRCv3 chghost module: Provides the chghost IRCv3.2 extension which
+# allows capable clients to learn when the host/ident of another user
+# changes without cycling the user. This module is compatible with the
+# hostcycle module. If both are loaded, clients supporting the chghost
+# extension will get the chghost message and won't see host cycling.
+#<module name="ircv3_chghost">
+
+#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#
 # Join flood module: Adds support for join flood protection +j X:Y.
 # Closes the channel for 60 seconds if X users join in Y seconds.
 #<module name="joinflood">
diff --git a/include/modules/cap.h b/include/modules/cap.h
new file mode 100644
index 000000000..e6f9340e8
--- /dev/null
+++ b/include/modules/cap.h
@@ -0,0 +1,316 @@
+/*
+ * InspIRCd -- Internet Relay Chat Daemon
+ *
+ *   Copyright (C) 2015 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/>.
+ */
+
+
+#pragma once
+
+#include "event.h"
+
+namespace Cap
+{
+	static const unsigned int MAX_CAPS = (sizeof(intptr_t) * 8) - 1;
+	static const intptr_t CAP_302_BIT = (intptr_t)1 << MAX_CAPS;
+	static const unsigned int MAX_VALUE_LENGTH = 100;
+
+	typedef intptr_t Ext;
+	class ExtItem : public LocalIntExt
+	{
+	 public:
+		ExtItem(Module* mod);
+		std::string serialize(SerializeFormat format, const Extensible* container, void* item) const;
+		void unserialize(SerializeFormat format, Extensible* container, const std::string& value);
+	};
+
+	class Capability;
+
+	enum Protocol
+	{
+		/** Supports capability negotiation protocol v3.1, or none
+		 */
+		CAP_LEGACY,
+
+		/** Supports capability negotiation v3.2
+		 */
+		CAP_302
+	};
+
+	class EventListener : public Events::ModuleEventListener
+	{
+	 public:
+		EventListener(Module* mod)
+			: ModuleEventListener(mod, "event/cap")
+		{
+		}
+
+		/** Called whenever a new client capability becomes available or unavailable
+		 * @param cap Capability being added or removed
+		 * @param add If true, the capability is being added, otherwise its being removed
+		 */
+		virtual void OnCapAddDel(Capability* cap, bool add) = 0;
+
+		/** Called whenever the value of a cap changes.
+		 * @param cap Capability whose value changed
+		 */
+		virtual void OnCapValueChange(Capability* cap) { }
+	};
+
+	class Manager : public DataProvider
+	{
+	 public:
+		Manager(Module* mod)
+			: DataProvider(mod, "capmanager")
+		{
+		}
+
+		/** Register a client capability.
+		 * Modules should call Capability::SetActive(true) instead of this method.
+		 * @param cap Capability to register
+		 */
+		virtual void AddCap(Capability* cap) = 0;
+
+		/** Unregister a client capability.
+		 * Modules should call Capability::SetActive(false) instead of this method.
+		 * @param cap Capability to unregister
+		 */
+		virtual void DelCap(Capability* cap) = 0;
+
+		/** Find a capability by name
+		 * @param name Capability to find
+		 * @return Capability object pointer if found, NULL otherwise
+		 */
+		virtual Capability* Find(const std::string& name) const = 0;
+
+		/** Notify manager when a value of a cap changed
+		 * @param cap Cap whose value changed
+		 */
+		virtual void NotifyValueChange(Capability* cap) = 0;
+	};
+
+	/** Represents a client capability.
+	 *
+	 * Capabilities offer extensions to the client to server protocol. They must be negotiated with clients before they have any effect on the protocol.
+	 * Each cap must have a unique name that is used during capability negotiation.
+	 *
+	 * After construction the cap is ready to be used by clients without any further setup, like other InspIRCd services.
+	 * The get() method accepts a user as parameter and can be used to check whether that user has negotiated usage of the cap. This is only known for local users.
+	 *
+	 * The cap module must be loaded for the capability to work. The IsRegistered() method can be used to query whether the cap is actually online or not.
+	 * The capability can be deactivated and reactivated with the SetActive() method. Deactivated caps behave as if they don't exist.
+	 *
+	 * It is possible to implement special behavior by inheriting from this class and overriding some of its methods.
+	 */
+	class Capability : public ServiceProvider, private dynamic_reference_base::CaptureHook
+	{
+		typedef size_t Bit;
+
+		/** Bit allocated to this cap, undefined if the cap is unregistered
+		 */
+		Bit bit;
+
+		/** Extension containing all caps set by a user. NULL if the cap is unregistered.
+		 */
+		ExtItem* extitem;
+
+		/** True if the cap is active. Only active caps are registered in the manager.
+		 */
+		bool active;
+
+		/** Reference to the cap manager object
+		 */
+		dynamic_reference<Manager> manager;
+
+		void OnCapture() CXX11_OVERRIDE
+		{
+			if (active)
+				SetActive(true);
+		}
+
+		void Unregister()
+		{
+			bit = 0;
+			extitem = NULL;
+		}
+
+		Ext AddToMask(Ext mask) const { return (mask | GetMask()); }
+		Ext DelFromMask(Ext mask) const { return (mask & (~GetMask())); }
+		Bit GetMask() const { return bit; }
+
+		friend class ManagerImpl;
+
+	 protected:
+		/** Notify the manager that the value of the capability changed.
+		 * Must be called if the value of the cap changes for any reason.
+		 */
+		void NotifyValueChange()
+		{
+			if (IsRegistered())
+				manager->NotifyValueChange(this);
+		}
+
+	 public:
+		/** Constructor, initializes the capability.
+		 * Caps are active by default.
+		 * @param mod Module providing the cap
+		 * @param Name Raw name of the cap as used in the protocol (CAP LS, etc.)
+		 */
+		Capability(Module* mod, const std::string& Name)
+			: ServiceProvider(mod, Name, SERVICE_CUSTOM)
+			, active(true)
+			, manager(mod, "capmanager")
+		{
+			Unregister();
+		}
+
+		~Capability()
+		{
+			SetActive(false);
+		}
+
+		void RegisterService() CXX11_OVERRIDE
+		{
+			manager.SetCaptureHook(this);
+			SetActive(true);
+		}
+
+		/** Check whether a user has the capability turned on.
+		 * This method is safe to call if the cap is unregistered and will return false.
+		 * @param user User to check
+		 * @return True if the user is using this capability, false otherwise
+		 */
+		bool get(User* user) const
+		{
+			if (!IsRegistered())
+				return false;
+			Ext caps = extitem->get(user);
+			return (caps & GetMask());
+		}
+
+		/** Turn the capability on/off for a user. If the cap is not registered this method has no effect.
+		 * @param user User to turn the cap on/off for
+		 * @param val True to turn the cap on, false to turn it off
+		 */
+		void set(User* user, bool val)
+		{
+			if (!IsRegistered())
+				return;
+			Ext curr = extitem->get(user);
+			extitem->set(user, (val ? AddToMask(curr) : DelFromMask(curr)));
+		}
+
+		/** Activate or deactivate the capability.
+		 * If activating, the cap is marked as active and if the manager is available the cap is registered in the manager.
+		 * If deactivating, the cap is marked as inactive and if it is registered, it will be unregistered.
+		 * Users who had the cap turned on will have it turned off automatically.
+		 * @param activate True to activate the cap, false to deactivate it
+		 */
+		void SetActive(bool activate)
+		{
+			active = activate;
+			if (manager)
+			{
+				if (activate)
+					manager->AddCap(this);
+				else
+					manager->DelCap(this);
+			}
+		}
+
+		/** Get the name of the capability that's used in the protocol
+		 * @return Name of the capability as used in the protocol
+		 */
+		const std::string& GetName() const { return name; }
+
+		/** Check whether the capability is active. The cap must be active and registered to be used by users.
+		 * @return True if the cap is active, false if it has been deactivated
+		 */
+		bool IsActive() const { return active; }
+
+		/** Check whether the capability is registered
+		 * The cap must be active and the manager must be available for a cap to be registered.
+		 * @return True if the cap is registered in the manager, false otherwise
+		 */
+		bool IsRegistered() const { return (extitem != NULL); }
+
+		/** Get the CAP negotiation protocol version of a user.
+		 * The cap must be registered for this to return anything other than CAP_LEGACY.
+		 * @param user User whose negotiation protocol version to query
+		 * @return One of the Capability::Protocol enum indicating the highest supported capability negotiation protocol version
+		 */
+		Protocol GetProtocol(LocalUser* user) const
+		{
+			return ((IsRegistered() && (extitem->get(user) & CAP_302_BIT)) ? CAP_302 : CAP_LEGACY);
+		}
+
+		/** Called when a user requests to turn this capability on or off.
+		 * @param user User requesting to change the state of the cap
+		 * @param add True if requesting to turn the cap on, false if requesting to turn it off
+		 * @return True to allow the request, false to reject it
+		 */
+		virtual bool OnRequest(LocalUser* user, bool add)
+		{
+			return true;
+		}
+
+		/** Called when a user requests a list of all capabilities and this capability is about to be included in the list.
+		 * The default behavior always includes the cap in the list.
+		 * @param user User querying a list capabilities
+		 * @return True to add this cap to the list sent to the user, false to not list it
+		 */
+		virtual bool OnList(LocalUser* user)
+		{
+			return true;
+		}
+
+		/** Query the value of this capability for a user
+		 * @param user User who will get the value of the capability
+		 * @return Value to show to the user. If NULL, the capability has no value (default).
+		 */
+		virtual const std::string* GetValue(LocalUser* user) const
+		{
+			return NULL;
+		}
+	};
+
+	/** Reference to a cap. The cap may be provided by another module.
+	 */
+	class Reference
+	{
+		dynamic_reference_nocheck<Capability> ref;
+
+	 public:
+		/** Constructor, initializes the capability reference
+		 * @param mod Module creating this object
+		 * @param Name Raw name of the cap as used in the protocol (CAP LS, etc.)
+		 */
+		Reference(Module* mod, const std::string& Name)
+			: ref(mod, "cap/" + Name)
+		{
+		}
+
+		/** Check whether a user has the referenced capability turned on.
+		 * @param user User to check
+		 * @return True if the user is using the referenced capability, false otherwise
+		 */
+		bool get(LocalUser* user)
+		{
+			if (ref)
+				return ref->get(user);
+			return false;
+		}
+	};
+}
diff --git a/include/modules/ircv3.h b/include/modules/ircv3.h
new file mode 100644
index 000000000..e03ee16fa
--- /dev/null
+++ b/include/modules/ircv3.h
@@ -0,0 +1,45 @@
+/*
+ * InspIRCd -- Internet Relay Chat Daemon
+ *
+ *   Copyright (C) 2015 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/>.
+ */
+
+
+#pragma once
+
+namespace IRCv3
+{
+	class WriteNeighborsWithCap;
+}
+
+class IRCv3::WriteNeighborsWithCap : public User::ForEachNeighborHandler
+{
+	const Cap::Capability& cap;
+	const std::string& msg;
+
+	void Execute(LocalUser* user) CXX11_OVERRIDE
+	{
+		if (cap.get(user))
+			user->Write(msg);
+	}
+
+ public:
+	WriteNeighborsWithCap(User* user, const std::string& message, const Cap::Capability& capability)
+		: cap(capability)
+		, msg(message)
+	{
+		user->ForEachNeighbor(*this, false);
+	}
+};
diff --git a/src/modules/m_cap.cpp b/src/modules/m_cap.cpp
new file mode 100644
index 000000000..3e9c37a34
--- /dev/null
+++ b/src/modules/m_cap.cpp
@@ -0,0 +1,430 @@
+/*
+ * InspIRCd -- Internet Relay Chat Daemon
+ *
+ *   Copyright (C) 2015 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"
+
+namespace Cap
+{
+	class ManagerImpl;
+}
+
+static Cap::ManagerImpl* managerimpl;
+
+class Cap::ManagerImpl : public Cap::Manager, public ReloadModule::EventListener
+{
+	/** Stores the cap state of a module being reloaded
+	 */
+	struct CapModData
+	{
+		struct Data
+		{
+			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)
+	{
+		if ((usercaps & cap->GetMask()) == adding)
+			return true;
+
+		return cap->OnRequest(user, adding);
+	}
+
+	Capability::Bit AllocateBit() const
+	{
+		Capability::Bit used = 0;
+		for (CapMap::const_iterator i = caps.begin(); i != caps.end(); ++i)
+		{
+			Capability* cap = i->second;
+			used |= cap->GetMask();
+		}
+
+		for (unsigned int i = 0; i < MAX_CAPS; i++)
+		{
+			Capability::Bit bit = (1 << i);
+			if (!(used & bit))
+				return bit;
+		}
+		throw ModuleException("Too many caps");
+	}
+
+	void OnReloadModuleSave(Module* mod, ReloadModule::CustomData& cd) CXX11_OVERRIDE
+	{
+		ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "OnReloadModuleSave()");
+		if (mod == creator)
+			return;
+
+		CapModData* capmoddata = new CapModData;
+		cd.add(this, capmoddata);
+
+		for (CapMap::iterator i = caps.begin(); i != caps.end(); ++i)
+		{
+			Capability* cap = i->second;
+			// Only save users of caps that belong to the module being reloaded
+			if (cap->creator != mod)
+				continue;
+
+			ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Module being reloaded implements cap %s, saving cap users", cap->GetName().c_str());
+			capmoddata->caps.push_back(CapModData::Data(cap));
+			CapModData::Data& capdata = capmoddata->caps.back();
+
+			// Populate list with uuids of users who are using the cap
+			const UserManager::LocalList& list = ServerInstance->Users.GetLocalUsers();
+			for (UserManager::LocalList::const_iterator j = list.begin(); j != list.end(); ++j)
+			{
+				LocalUser* user = *j;
+				if (cap->get(user))
+					capdata.users.push_back(user->uuid);
+			}
+		}
+	}
+
+	void OnReloadModuleRestore(Module* mod, void* data) CXX11_OVERRIDE
+	{
+		CapModData* capmoddata = static_cast<CapModData*>(data);
+		for (std::vector<CapModData::Data>::const_iterator i = capmoddata->caps.begin(); i != capmoddata->caps.end(); ++i)
+		{
+			const CapModData::Data& capdata = *i;
+			Capability* cap = ManagerImpl::Find(capdata.name);
+			if (!cap)
+			{
+				ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Cap %s is no longer available after reload", capdata.name.c_str());
+				continue;
+			}
+
+			// Set back the cap for all users who were using it before the reload
+			for (std::vector<std::string>::const_iterator j = capdata.users.begin(); j != capdata.users.end(); ++j)
+			{
+				const std::string& uuid = *j;
+				User* user = ServerInstance->FindUUID(uuid);
+				if (!user)
+				{
+					ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "User %s is gone when trying to restore cap %s", uuid.c_str(), capdata.name.c_str());
+					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()
+	{
+		for (CapMap::iterator i = caps.begin(); i != caps.end(); ++i)
+		{
+			Capability* cap = i->second;
+			cap->Unregister();
+		}
+	}
+
+	void AddCap(Cap::Capability* cap) CXX11_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->Log(MODNAME, LOG_DEBUG, "Registering cap %s", cap->GetName().c_str());
+		cap->bit = AllocateBit();
+		cap->extitem = &capext;
+		caps.insert(std::make_pair(cap->GetName(), cap));
+		ServerInstance->Modules.AddReferent("cap/" + cap->GetName(), cap);
+
+		FOREACH_MOD_CUSTOM(evprov, Cap::EventListener, OnCapAddDel, (cap, true));
+	}
+
+	void DelCap(Cap::Capability* cap) CXX11_OVERRIDE
+	{
+		// No-op if the cap is not registered, see AddCap() above
+		if (!cap->IsRegistered())
+			return;
+
+		ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Unregistering cap %s", cap->GetName().c_str());
+
+		// Fire the event first so modules can still see who is using the cap which is being unregistered
+		FOREACH_MOD_CUSTOM(evprov, Cap::EventListener, OnCapAddDel, (cap, false));
+
+		// Turn off the cap for all users
+		const UserManager::LocalList& list = ServerInstance->Users.GetLocalUsers();
+		for (UserManager::LocalList::const_iterator i = list.begin(); i != list.end(); ++i)
+		{
+			LocalUser* user = *i;
+			cap->set(user, false);
+		}
+
+		ServerInstance->Modules.DelReferent(cap);		
+		cap->Unregister();
+		caps.erase(cap->GetName());
+	}
+
+	Capability* Find(const std::string& capname) const CXX11_OVERRIDE
+	{
+		CapMap::const_iterator it = caps.find(capname);
+		if (it != caps.end())
+			return it->second;
+		return NULL;
+	}
+
+	void NotifyValueChange(Capability* cap) CXX11_OVERRIDE
+	{
+		ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Cap %s changed value", cap->GetName().c_str());
+		FOREACH_MOD_CUSTOM(evprov, 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::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 (CapMap::const_iterator i = caps.begin(); i != caps.end(); ++i)
+		{
+			Capability* cap = i->second;
+			if (!(show_caps & cap->GetMask()))
+				continue;
+
+			if ((show_all) && (!cap->OnList(user)))
+				continue;
+
+			if (minus_prefix)
+				out.push_back('-');
+			out.append(cap->GetName());
+
+			if (show_values)
+			{
+				const std::string* capvalue = cap->GetValue(user);
+				if ((capvalue) && (!capvalue->empty()) && (capvalue->find(' ') == std::string::npos))
+				{
+					out.push_back('=');
+					out.append(*capvalue, 0, MAX_VALUE_LENGTH);
+				}
+			}
+			out.push_back(' ');
+		}
+	}
+
+	void HandleClear(LocalUser* user, std::string& result)
+	{
+		HandleList(result, user, false, false, true);
+		capext.unset(user);
+	}
+};
+
+Cap::ExtItem::ExtItem(Module* mod)
+	: LocalIntExt("caps", ExtensionItem::EXT_USER, mod)
+{
+}
+
+std::string Cap::ExtItem::serialize(SerializeFormat format, const Extensible* container, void* item) const
+{
+	std::string ret;
+	// 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 ((format == FORMAT_NETWORK) || (!user))
+		return ret;
+
+	// List requested caps
+	managerimpl->HandleList(ret, 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.
+	Protocol protocol = managerimpl->GetProtocol(user);
+	if (format == FORMAT_USER)
+		ret.append("capversion=3.");
+	else if (!ret.empty())
+		ret.erase(ret.length()-1);
+
+	if (protocol == CAP_302)
+		ret.push_back('2');
+	else
+		ret.push_back('1');
+
+	return ret;
+}
+
+void Cap::ExtItem::unserialize(SerializeFormat format, Extensible* container, const std::string& value)
+{
+	if (format == FORMAT_NETWORK)
+		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
+	const char verchar = *value.rbegin();
+	if (verchar == '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 CommandCap : public SplitCommand
+{
+	Events::ModuleEventProvider evprov;
+	Cap::ManagerImpl manager;
+
+	static void DisplayResult(LocalUser* user, std::string& result)
+	{
+		if (result.size() > 5)
+			result.erase(result.end()-1);
+		user->WriteCommand("CAP", result);
+	}
+
+ public:
+	LocalIntExt holdext;
+
+	CommandCap(Module* mod)
+		: SplitCommand(mod, "CAP", 1)
+		, evprov(mod, "event/cap")
+		, manager(mod, evprov)
+		, holdext("cap_hold", ExtensionItem::EXT_USER, mod)
+	{
+		works_before_reg = true;
+	}
+
+	CmdResult HandleLocal(const std::vector<std::string>& parameters, LocalUser* user) CXX11_OVERRIDE
+	{
+		if (user->registered != REG_ALL)
+			holdext.set(user, 1);
+
+		std::string subcommand(parameters[0].length(), ' ');
+		std::transform(parameters[0].begin(), parameters[0].end(), subcommand.begin(), ::toupper);
+
+		if (subcommand == "REQ")
+		{
+			if (parameters.size() < 2)
+				return CMD_FAILURE;
+
+			std::string result = (manager.HandleReq(user, parameters[1]) ? "ACK :" : "NAK :");
+			result.append(parameters[1]);
+			user->WriteCommand("CAP", result);
+		}
+		else if (subcommand == "END")
+		{
+			holdext.unset(user);
+		}
+		else if ((subcommand == "LS") || (subcommand == "LIST"))
+		{
+			const bool is_ls = (subcommand.length() == 2);
+			if ((is_ls) && (parameters.size() > 1) && (parameters[1] == "302"))
+				manager.Set302Protocol(user);
+
+			std::string result = subcommand + " :";
+			// Show values only if supports v3.2 and doing LS
+			manager.HandleList(result, user, is_ls, ((is_ls) && (manager.GetProtocol(user) != Cap::CAP_LEGACY)));
+			DisplayResult(user, result);
+		}
+		else if ((subcommand == "CLEAR") && (manager.GetProtocol(user) == Cap::CAP_LEGACY))
+		{
+			std::string result = "ACK :";
+			manager.HandleClear(user, result);
+			DisplayResult(user, result);
+		}
+		else
+		{
+			user->WriteNumeric(ERR_INVALIDCAPSUBCOMMAND, "%s :Invalid CAP subcommand", subcommand.c_str());
+			return CMD_FAILURE;
+		}
+
+		return CMD_SUCCESS;
+	}
+};
+
+class ModuleCap : public Module
+{
+	CommandCap cmd;
+
+ public:
+	ModuleCap()
+		: cmd(this)
+	{
+	}
+
+	ModResult OnCheckReady(LocalUser* user) CXX11_OVERRIDE
+	{
+		return (cmd.holdext.get(user) ? MOD_RES_DENY : MOD_RES_PASSTHRU);
+	}
+
+	Version GetVersion() CXX11_OVERRIDE
+	{
+		return Version("Provides support for CAP capability negotiation", VF_VENDOR);
+	}
+};
+
+MODULE_INIT(ModuleCap)
diff --git a/src/modules/m_hostcycle.cpp b/src/modules/m_hostcycle.cpp
index d4def6473..b33c101ef 100644
--- a/src/modules/m_hostcycle.cpp
+++ b/src/modules/m_hostcycle.cpp
@@ -19,12 +19,15 @@
 
 
 #include "inspircd.h"
+#include "modules/cap.h"
 
 class ModuleHostCycle : public Module
 {
+	Cap::Reference chghostcap;
+
 	/** Send fake quit/join/mode messages for host or ident cycle.
 	 */
-	static void DoHostCycle(User* user, const std::string& newident, const std::string& newhost, const char* quitmsg)
+	void DoHostCycle(User* user, const std::string& newident, const std::string& newhost, const char* quitmsg)
 	{
 		// GetFullHost() returns the original data at the time this function is called
 		const std::string quitline = ":" + user->GetFullHost() + " QUIT :" + quitmsg;
@@ -40,7 +43,7 @@ class ModuleHostCycle : public Module
 		for (std::map<User*,bool>::iterator i = exceptions.begin(); i != exceptions.end(); ++i)
 		{
 			LocalUser* u = IS_LOCAL(i->first);
-			if (u && !u->quitting)
+			if ((u) && (!u->quitting) && (!chghostcap.get(u)))
 			{
 				if (i->second)
 				{
@@ -80,6 +83,8 @@ class ModuleHostCycle : public Module
 					continue;
 				if (u->already_sent == silent_id)
 					continue;
+				if (chghostcap.get(u))
+					continue;
 
 				if (u->already_sent != seen_id)
 				{
@@ -95,6 +100,11 @@ class ModuleHostCycle : public Module
 	}
 
  public:
+	ModuleHostCycle()
+		: chghostcap(this, "chghost")
+	{
+	}
+
 	void OnChangeIdent(User* user, const std::string& newident) CXX11_OVERRIDE
 	{
 		DoHostCycle(user, newident, user->dhost, "Changing ident");
diff --git a/src/modules/m_ircv3.cpp b/src/modules/m_ircv3.cpp
index caee0d329..5275e9bd5 100644
--- a/src/modules/m_ircv3.cpp
+++ b/src/modules/m_ircv3.cpp
@@ -19,32 +19,13 @@
 #include "inspircd.h"
 #include "modules/account.h"
 #include "modules/cap.h"
-
-class WriteNeighboursWithExt : public User::ForEachNeighborHandler
-{
-	const LocalIntExt& ext;
-	const std::string& msg;
-
-	void Execute(LocalUser* user) CXX11_OVERRIDE
-	{
-		if (ext.get(user))
-			user->Write(msg);
-	}
-
- public:
-	WriteNeighboursWithExt(User* user, const std::string& message, const LocalIntExt& extension)
-		: ext(extension)
-		, msg(message)
-	{
-		user->ForEachNeighbor(*this, false);
-	}
-};
+#include "modules/ircv3.h"
 
 class ModuleIRCv3 : public Module, public AccountEventListener
 {
-	GenericCap cap_accountnotify;
-	GenericCap cap_awaynotify;
-	GenericCap cap_extendedjoin;
+	Cap::Capability cap_accountnotify;
+	Cap::Capability cap_awaynotify;
+	Cap::Capability cap_extendedjoin;
 
 	CUList last_excepts;
 
@@ -76,7 +57,7 @@ class ModuleIRCv3 : public Module, public AccountEventListener
 		else
 			line += newaccount;
 
-		WriteNeighboursWithExt(user, line, cap_accountnotify.ext);
+		IRCv3::WriteNeighborsWithCap(user, line, cap_accountnotify);
 	}
 
 	void OnUserJoin(Membership* memb, bool sync, bool created, CUList& excepts) CXX11_OVERRIDE
@@ -105,7 +86,7 @@ class ModuleIRCv3 : public Module, public AccountEventListener
 		{
 			// Send the extended join line if the current member is local, has the extended-join cap and isn't excepted
 			User* member = IS_LOCAL(it->first);
-			if ((member) && (cap_extendedjoin.ext.get(member)) && (excepts.find(member) == excepts.end()))
+			if ((member) && (cap_extendedjoin.get(member)) && (excepts.find(member) == excepts.end()))
 			{
 				// Construct the lines we're going to send if we haven't constructed them already
 				if (line.empty())
@@ -162,7 +143,7 @@ class ModuleIRCv3 : public Module, public AccountEventListener
 			if (!awaymsg.empty())
 				line += " :" + awaymsg;
 
-			WriteNeighboursWithExt(user, line, cap_awaynotify.ext);
+			IRCv3::WriteNeighborsWithCap(user, line, cap_awaynotify);
 		}
 		return MOD_RES_PASSTHRU;
 	}
@@ -179,7 +160,7 @@ class ModuleIRCv3 : public Module, public AccountEventListener
 		{
 			// Send the away notify line if the current member is local, has the away-notify cap and isn't excepted
 			User* member = IS_LOCAL(it->first);
-			if ((member) && (cap_awaynotify.ext.get(member)) && (last_excepts.find(member) == last_excepts.end()))
+			if ((member) && (cap_awaynotify.get(member)) && (last_excepts.find(member) == last_excepts.end()))
 			{
 				member->Write(line);
 			}
diff --git a/src/modules/m_ircv3_capnotify.cpp b/src/modules/m_ircv3_capnotify.cpp
new file mode 100644
index 000000000..b19c2665d
--- /dev/null
+++ b/src/modules/m_ircv3_capnotify.cpp
@@ -0,0 +1,149 @@
+/*
+ * InspIRCd -- Internet Relay Chat Daemon
+ *
+ *   Copyright (C) 2015 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/cap.h"
+#include "modules/reload.h"
+
+class CapNotify : public Cap::Capability
+{
+	bool OnRequest(LocalUser* user, bool add) CXX11_OVERRIDE
+	{
+		// Users using the negotiation protocol v3.2 or newer may not turn off cap-notify
+		if ((!add) && (GetProtocol(user) != Cap::CAP_LEGACY))
+			return false;
+		return true;
+	}
+
+	bool OnList(LocalUser* user) CXX11_OVERRIDE
+	{
+		// If the client supports 3.2 enable cap-notify for them
+		if (GetProtocol(user) != Cap::CAP_LEGACY)
+			set(user, true);
+		return true;
+	}
+
+ public:
+	CapNotify(Module* mod)
+		: Cap::Capability(mod, "cap-notify")
+	{
+	}
+};
+
+class ModuleIRCv3CapNotify : public Module, public Cap::EventListener, public ReloadModule::EventListener
+{
+	CapNotify capnotify;
+	std::string reloadedmod;
+	std::vector<std::string> reloadedcaps;
+
+	void Send(const std::string& capname, Cap::Capability* cap, bool add)
+	{
+		std::string msg = (add ? "ADD :" : "DEL :");
+		msg.append(capname);
+		std::string msgwithval = msg;
+		msgwithval.push_back('=');
+		std::string::size_type msgpos = msgwithval.size();
+
+		const UserManager::LocalList& list = ServerInstance->Users.GetLocalUsers();
+		for (UserManager::LocalList::const_iterator i = list.begin(); i != list.end(); ++i)
+		{
+			LocalUser* user = *i;
+			if (!capnotify.get(user))
+				continue;
+
+			// If the cap is being added and the client supports cap values then show the value, if any
+			if ((add) && (capnotify.GetProtocol(user) != Cap::CAP_LEGACY))
+			{
+				const std::string* capvalue = cap->GetValue(user);
+				if ((capvalue) && (!capvalue->empty()))
+				{
+					msgwithval.append(*capvalue);
+					user->WriteCommand("CAP", msgwithval);
+					msgwithval.erase(msgpos);
+					continue;
+				}
+			}
+			user->WriteCommand("CAP", msg);
+		}
+	}
+
+ public:
+	ModuleIRCv3CapNotify()
+		: Cap::EventListener(this)
+		, ReloadModule::EventListener(this)
+		, capnotify(this)
+	{
+	}
+
+	void OnCapAddDel(Cap::Capability* cap, bool add) CXX11_OVERRIDE
+	{
+		if (cap->creator == this)
+			return;
+
+		if (cap->creator->ModuleSourceFile == reloadedmod)
+		{
+			if (!add)
+				reloadedcaps.push_back(cap->GetName());
+			return;
+		}
+		Send(cap->GetName(), cap, add);
+	}
+
+	void OnCapValueChange(Cap::Capability* cap) CXX11_OVERRIDE
+	{
+		// The value of a cap has changed, send CAP DEL and CAP NEW with the new value
+		Send(cap->GetName(), cap, false);
+		Send(cap->GetName(), cap, true);
+	}
+
+	void OnReloadModuleSave(Module* mod, ReloadModule::CustomData& cd) CXX11_OVERRIDE
+	{
+		if (mod == this)
+			return;
+		reloadedmod = mod->ModuleSourceFile;
+		// Request callback when reload is complete
+		cd.add(this, NULL);
+	}
+
+	void OnReloadModuleRestore(Module* mod, void* data) CXX11_OVERRIDE
+	{
+		// Reloading can change the set of caps provided by a module so assuming that if the reload succeded all
+		// caps that the module previously provided are available or all were lost if the reload failed is wrong.
+		// Instead, we verify the availability of each cap individually.
+		dynamic_reference_nocheck<Cap::Manager> capmanager(this, "capmanager");
+		if (capmanager)
+		{
+			for (std::vector<std::string>::const_iterator i = reloadedcaps.begin(); i != reloadedcaps.end(); ++i)
+			{
+				const std::string& capname = *i;
+				if (!capmanager->Find(capname))
+					Send(capname, NULL, false);
+			}
+		}
+		reloadedmod.clear();
+		reloadedcaps.clear();
+	}
+
+	Version GetVersion() CXX11_OVERRIDE
+	{
+		return Version("Provides the cap-notify IRCv3.2 extension", VF_VENDOR);
+	}
+};
+
+MODULE_INIT(ModuleIRCv3CapNotify)
diff --git a/src/modules/m_ircv3_chghost.cpp b/src/modules/m_ircv3_chghost.cpp
new file mode 100644
index 000000000..af3503108
--- /dev/null
+++ b/src/modules/m_ircv3_chghost.cpp
@@ -0,0 +1,57 @@
+/*
+ * InspIRCd -- Internet Relay Chat Daemon
+ *
+ *   Copyright (C) 2015 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/cap.h"
+#include "modules/ircv3.h"
+
+class ModuleIRCv3ChgHost : public Module
+{
+	Cap::Capability cap;
+
+	void DoChgHost(User* user, const std::string& ident, const std::string& host)
+	{
+		std::string line(1, ':');
+		line.append(user->GetFullHost()).append(" CHGHOST ").append(ident).append(1, ' ').append(host);
+		IRCv3::WriteNeighborsWithCap(user, line, cap);
+	}
+
+ public:
+	ModuleIRCv3ChgHost()
+		: cap(this, "chghost")
+	{
+	}
+
+	void OnChangeIdent(User* user, const std::string& newident) CXX11_OVERRIDE
+	{
+		DoChgHost(user, newident, user->dhost);
+	}
+
+	void OnChangeHost(User* user, const std::string& newhost) CXX11_OVERRIDE
+	{
+		DoChgHost(user, user->ident, newhost);
+	}
+
+	Version GetVersion() CXX11_OVERRIDE
+	{
+		return Version("Provides the chghost IRCv3.2 extension", VF_VENDOR);
+	}
+};
+
+MODULE_INIT(ModuleIRCv3ChgHost)
diff --git a/src/modules/m_namesx.cpp b/src/modules/m_namesx.cpp
index c701f16bf..c906322bf 100644
--- a/src/modules/m_namesx.cpp
+++ b/src/modules/m_namesx.cpp
@@ -25,7 +25,7 @@
 
 class ModuleNamesX : public Module
 {
-	GenericCap cap;
+	Cap::Capability cap;
  public:
 	ModuleNamesX() : cap(this, "multi-prefix")
 	{
@@ -52,7 +52,7 @@ class ModuleNamesX : public Module
 		{
 			if ((parameters.size()) && (!strcasecmp(parameters[0].c_str(),"NAMESX")))
 			{
-				cap.ext.set(user, 1);
+				cap.set(user, true);
 				return MOD_RES_DENY;
 			}
 		}
@@ -61,7 +61,7 @@ class ModuleNamesX : public Module
 
 	ModResult OnNamesListItem(User* issuer, Membership* memb, std::string& prefixes, std::string& nick) CXX11_OVERRIDE
 	{
-		if (cap.ext.get(issuer))
+		if (cap.get(issuer))
 			prefixes = memb->GetAllPrefixChars();
 
 		return MOD_RES_PASSTHRU;
@@ -69,7 +69,7 @@ class ModuleNamesX : public Module
 
 	void OnSendWhoLine(User* source, const std::vector<std::string>& params, User* user, Membership* memb, std::string& line) CXX11_OVERRIDE
 	{
-		if ((!memb) || (!cap.ext.get(source)))
+		if ((!memb) || (!cap.get(source)))
 			return;
 
 		// Channel names can contain ":", and ":" as a 'start-of-token' delimiter is
diff --git a/src/modules/m_sasl.cpp b/src/modules/m_sasl.cpp
index a38ed1a1b..20243370d 100644
--- a/src/modules/m_sasl.cpp
+++ b/src/modules/m_sasl.cpp
@@ -24,6 +24,41 @@
 #include "modules/sasl.h"
 #include "modules/ssl.h"
 
+class SASLCap : public Cap::Capability
+{
+	std::string mechlist;
+
+	bool OnRequest(LocalUser* user, bool adding) CXX11_OVERRIDE
+	{
+		// Requesting this cap is allowed anytime
+		if (adding)
+			return true;
+
+		// But removing it can only be done when unregistered
+		return (user->registered != REG_ALL);
+	}
+
+	const std::string* GetValue(LocalUser* user) const CXX11_OVERRIDE
+	{
+		return &mechlist;
+	}
+
+ public:
+	SASLCap(Module* mod)
+		: Cap::Capability(mod, "sasl")
+	{
+	}
+
+	void SetMechlist(const std::string& newmechlist)
+	{
+		if (mechlist == newmechlist)
+			return;
+
+		mechlist = newmechlist;
+		NotifyValueChange();
+	}
+};
+
 enum SaslState { SASL_INIT, SASL_COMM, SASL_DONE };
 enum SaslResult { SASL_OK, SASL_FAIL, SASL_ABORT };
 
@@ -179,8 +214,8 @@ class CommandAuthenticate : public Command
 {
  public:
 	SimpleExtItem<SaslAuthenticator>& authExt;
-	GenericCap& cap;
-	CommandAuthenticate(Module* Creator, SimpleExtItem<SaslAuthenticator>& ext, GenericCap& Cap)
+	Cap::Capability& cap;
+	CommandAuthenticate(Module* Creator, SimpleExtItem<SaslAuthenticator>& ext, Cap::Capability& Cap)
 		: Command(Creator, "AUTHENTICATE", 1), authExt(ext), cap(Cap)
 	{
 		works_before_reg = true;
@@ -191,7 +226,7 @@ class CommandAuthenticate : public Command
 		/* Only allow AUTHENTICATE on unregistered clients */
 		if (user->registered != REG_ALL)
 		{
-			if (!cap.ext.get(user))
+			if (!cap.get(user))
 				return CMD_FAILURE;
 
 			SaslAuthenticator *sasl = authExt.get(user);
@@ -247,7 +282,7 @@ class CommandSASL : public Command
 class ModuleSASL : public Module
 {
 	SimpleExtItem<SaslAuthenticator> authExt;
-	GenericCap cap;
+	SASLCap cap;
 	CommandAuthenticate auth;
 	CommandSASL sasl;
 	Events::ModuleEventProvider sasleventprov;
@@ -255,7 +290,7 @@ class ModuleSASL : public Module
  public:
 	ModuleSASL()
 		: authExt("sasl_auth", ExtensionItem::EXT_USER, this)
-		, cap(this, "sasl")
+		, cap(this)
 		, auth(this, authExt, cap)
 		, sasl(this, authExt)
 		, sasleventprov(this, "event/sasl")
@@ -286,6 +321,12 @@ class ModuleSASL : public Module
 		return MOD_RES_PASSTHRU;
 	}
 
+	void OnDecodeMetaData(Extensible* target, const std::string& extname, const std::string& extdata) CXX11_OVERRIDE
+	{
+		if ((target == NULL) && (extname == "saslmechlist"))
+			cap.SetMechlist(extdata);
+	}
+
 	Version GetVersion() CXX11_OVERRIDE
 	{
 		return Version("Provides support for IRC Authentication Layer (aka: SASL) via AUTHENTICATE.", VF_VENDOR);
diff --git a/src/modules/m_starttls.cpp b/src/modules/m_starttls.cpp
index b05302fa9..a47480728 100644
--- a/src/modules/m_starttls.cpp
+++ b/src/modules/m_starttls.cpp
@@ -80,7 +80,7 @@ class CommandStartTLS : public SplitCommand
 class ModuleStartTLS : public Module
 {
 	CommandStartTLS starttls;
-	GenericCap tls;
+	Cap::Capability tls;
 	dynamic_reference_nocheck<IOHookProvider> ssl;
 
  public:
diff --git a/src/modules/m_uhnames.cpp b/src/modules/m_uhnames.cpp
index 90bac54f5..ce9c517f4 100644
--- a/src/modules/m_uhnames.cpp
+++ b/src/modules/m_uhnames.cpp
@@ -24,9 +24,9 @@
 
 class ModuleUHNames : public Module
 {
- public:
-	GenericCap cap;
+	Cap::Capability cap;
 
+ public:
 	ModuleUHNames() : cap(this, "userhost-in-names")
 	{
 	}
@@ -52,7 +52,7 @@ class ModuleUHNames : public Module
 		{
 			if ((parameters.size()) && (!strcasecmp(parameters[0].c_str(),"UHNAMES")))
 			{
-				cap.ext.set(user, 1);
+				cap.set(user, true);
 				return MOD_RES_DENY;
 			}
 		}
@@ -61,7 +61,7 @@ class ModuleUHNames : public Module
 
 	ModResult OnNamesListItem(User* issuer, Membership* memb, std::string& prefixes, std::string& nick) CXX11_OVERRIDE
 	{
-		if (cap.ext.get(issuer))
+		if (cap.get(issuer))
 			nick = memb->user->GetFullHost();
 
 		return MOD_RES_PASSTHRU;