Add rewritten m_cap module

- Caps are now managed by m_cap
- Each cap uses one bit in an extension item shared with other caps

7 files changed, 457 insertions, 21 deletions

diff --git a/include/modules/cap.h b/include/modules/cap.h
new file mode 100644
index 000000000..9dd44a4aa
--- /dev/null
+++ b/include/modules/cap.h
@@ -0,0 +1,191 @@
+/*
+ * 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;
+	typedef intptr_t Ext;
+	typedef LocalIntExt ExtItem;
+	class Capability;
+
+	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;
+	};
+
+	/** 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.
+	 */
+	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;
+
+	 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); }
+	};
+}
diff --git a/src/modules/m_cap.cpp b/src/modules/m_cap.cpp
new file mode 100644
index 000000000..9e857ad28
--- /dev/null
+++ b/src/modules/m_cap.cpp
@@ -0,0 +1,245 @@
+/*
+ * 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"
+
+namespace Cap
+{
+	class ManagerImpl;
+}
+
+class Cap::ManagerImpl : public Cap::Manager
+{
+	typedef insp::flat_map<std::string, Capability*, irc::insensitive_swo> CapMap;
+
+	ExtItem capext;
+	CapMap caps;
+
+	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");
+	}
+
+ public:
+	ManagerImpl(Module* mod)
+		: Cap::Manager(mod)
+		, capext("caps", ExtensionItem::EXT_USER, mod)
+	{
+	}
+
+	~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));
+	}
+
+	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());
+
+		// 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);
+		}
+
+		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;
+	}
+
+	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)
+				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 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 (minus_prefix)
+				out.push_back('-');
+			out.append(cap->GetName()).push_back(' ');
+		}
+	}
+
+	void HandleClear(LocalUser* user, std::string& result)
+	{
+		HandleList(result, user, false, true);
+		capext.unset(user);
+	}
+};
+
+class CommandCap : public SplitCommand
+{
+	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)
+		, manager(mod)
+		, 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);
+
+			std::string result = subcommand + " :";
+			manager.HandleList(result, user, is_ls);
+			DisplayResult(user, result);
+		}
+		else if (subcommand == "CLEAR")
+		{
+			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_ircv3.cpp b/src/modules/m_ircv3.cpp
index 123d07069..c99d920ba 100644
--- a/src/modules/m_ircv3.cpp
+++ b/src/modules/m_ircv3.cpp
@@ -22,7 +22,7 @@
 
 class WriteNeighborsWithCap : public User::ForEachNeighborHandler
 {
-	const LocalIntExt& cap;
+	const Cap::Capability& cap;
 	const std::string& msg;
 
 	void Execute(LocalUser* user) CXX11_OVERRIDE
@@ -32,8 +32,8 @@ class WriteNeighborsWithCap : public User::ForEachNeighborHandler
 	}
 
  public:
-	WriteNeighborsWithCap(User* user, const std::string& message, const GenericCap& capability)
-		: cap(capability.ext)
+	WriteNeighborsWithCap(User* user, const std::string& message, const Cap::Capability& capability)
+		: cap(capability)
 		, msg(message)
 	{
 		user->ForEachNeighbor(*this, false);
@@ -42,9 +42,9 @@ class WriteNeighborsWithCap : public User::ForEachNeighborHandler
 
 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;
 
@@ -105,7 +105,7 @@ 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())
@@ -179,7 +179,7 @@ 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_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 341b3aea7..297abad85 100644
--- a/src/modules/m_sasl.cpp
+++ b/src/modules/m_sasl.cpp
@@ -179,8 +179,8 @@ 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 +191,7 @@ 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 +247,7 @@ class CommandSASL : public Command
 class ModuleSASL : public Module
 {
 	SimpleExtItem<SaslAuthenticator> authExt;
-	GenericCap cap;
+	Cap::Capability cap;
 	CommandAuthenticate auth;
 	CommandSASL sasl;
 	Events::ModuleEventProvider sasleventprov;
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;