Add initial mod_component for XEP-0114 support. Albert, where are you?

1 files changed, 217 insertions, 0 deletions

diff --git a/plugins/mod_component.lua b/plugins/mod_component.lua
new file mode 100644
index 00000000..57679ca9
--- /dev/null
+++ b/plugins/mod_component.lua
@@ -0,0 +1,217 @@
+-- Prosody IM v0.4
+-- Copyright (C) 2008-2009 Matthew Wild
+-- Copyright (C) 2008-2009 Waqas Hussain
+-- 
+-- This project is MIT/X11 licensed. Please see the
+-- COPYING file in the source package for more information.
+--
+
+if module:get_host_type() ~= "component" then
+	error("Don't load mod_component manually, it should be for a component, please see http://prosody.im/doc/components", 0);
+end
+
+local t_concat = table.concat;
+
+local connlisteners = require "net.connlisteners";
+local cm_register_component = require "core.componentmanager".register_component;
+local uuid_gen = require "util.uuid".generate;
+local sha1 = require "util.hashes".sha1;
+local st = stanza;
+local init_xmlhandlers = require "core.xmlhandlers";
+
+local sessions = {};
+
+local log = module._log;
+
+local component_listener = { default_port = 5347; default_mode = "*a"; };
+
+local xmlns_component = 'jabber:component:accept';
+
+--- Callbacks/data for xmlhandlers to handle streams for us ---
+
+local stream_callbacks = { stream_tag = "http://etherx.jabber.org/streams|stream", default_ns = xmlns_component };
+
+function stream_callbacks.error(session, error, data, data2)
+	log("warn", "Error processing component stream: "..tostring(error));
+	if error == "no-stream" then
+		session:close("invalid-namespace");
+	elseif error == "xml-parse-error" and data == "unexpected-element-close" then
+		session.log("debug", "Unexpected close of '%s' tag", data2);
+		session:close("xml-not-well-formed");
+	else
+		session.log("debug", "External component %s XML parse error: %s", tostring(session.host), tostring(error));
+		print(data, debug.traceback())
+		session:close("xml-not-well-formed");
+	end
+end
+
+function stream_callbacks.streamopened(session, attr)
+	if config.get(attr.to, "core", "component_module") ~= "component" then
+		-- Trying to act as a component domain which 
+		-- hasn't been configured
+		session:close{ condition = "host-unknown", text = tostring(attr.to).." does not match any configured external components" };
+		return;
+	end
+	
+	-- Store the original host (this is used for config, etc.)
+	session.user = attr.to;
+	-- Set the host for future reference
+	session.host = config.get(attr.to, "core", "component_address") or attr.to;
+	-- Note that we don't create the internal component 
+	-- until after the external component auths successfully
+
+	session.streamid = uuid_gen();
+	session.notopen = nil;
+	
+	session.send(st.stanza("stream:stream", { xmlns=xmlns_component,
+			["xmlns:stream"]='http://etherx.jabber.org/streams', id=session.streamid, from=session.host }):top_tag());
+
+end
+
+function stream_callbacks.streamclosed(session)
+end
+
+local core_process_stanza = core_process_stanza;
+
+function stream_callbacks.handlestanza(session, stanza)
+	-- Namespaces are icky.
+	log("warn", "Handing stanza with name %s", stanza.name);
+	if stanza.name ~= "handshake" then
+		return core_process_stanza(session, stanza);
+	else
+		handle_component_auth(session, stanza);
+	end
+end
+
+--- Handle authentication attempts by components
+function handle_component_auth(session, stanza)
+	if (not session.host) or #stanza.tags > 0 then
+		session:close("not-authorized");
+		return;
+	end
+	
+	local secret = config.get(session.user, "core", "component_secret");
+	if not secret then
+		log("warn", "Component attempted to identify as %s, but component_password is not set", session.user);
+		session:close("not-authorized");
+		return;
+	end
+	
+	local supplied_token = t_concat(stanza);
+	local calculated_token = sha1(session.streamid..secret, true);
+	if supplied_token:lower() ~= calculated_token:lower() then
+		session:close{ condition = "not-authorized", text = "Given token does not match calculated token" };
+		return;
+	end
+	
+	
+	-- Authenticated now
+	
+	-- If component not already created for this host, create one now
+	if not hosts[session.host].connected then
+		local send = session.send;
+		session.component_session = cm_register_component(session.host, function (_, data) return send(data); end);
+		hosts[session.host].connected = true;
+	else
+		log("error", "Multiple components bound to the same address, first one wins (TODO: Implement stanza distribution)");
+	end
+	
+	-- Signal successful authentication
+	session.send(st.stanza("handshake"));
+end
+
+module:add_handler("component", "handshake", xmlns_component, handle_component_auth);
+
+--[[
+-- Helper function to deal with errors processing component stanzas
+local function handleerr(err) log("error", "Traceback[component]: %s: %s", tostring(err), debug.traceback()); end
+function stream_callbacks.handlestanza(a, b)
+	xpcall(function () core_process_stanza(a, b) end, handleerr);
+end
+]]
+
+--- Closing a component connection
+local stream_xmlns_attr = {xmlns='urn:ietf:params:xml:ns:xmpp-streams'};
+local function session_close(session, reason)
+	local log = session.log or log;
+	if session.conn then
+		if reason then
+			if type(reason) == "string" then -- assume stream error
+				log("info", "Disconnecting component, <stream:error> is: %s", reason);
+				session.send(st.stanza("stream:error"):tag(reason, {xmlns = 'urn:ietf:params:xml:ns:xmpp-streams' }));
+			elseif type(reason) == "table" then
+				if reason.condition then
+					local stanza = st.stanza("stream:error"):tag(reason.condition, stream_xmlns_attr):up();
+					if reason.text then
+						stanza:tag("text", stream_xmlns_attr):text(reason.text):up();
+					end
+					if reason.extra then
+						stanza:add_child(reason.extra);
+					end
+					log("info", "Disconnecting component, <stream:error> is: %s", tostring(stanza));
+					session.send(stanza);
+				elseif reason.name then -- a stanza
+					log("info", "Disconnecting component, <stream:error> is: %s", tostring(reason));
+					session.send(reason);
+				end
+			end
+		end
+		session.send("</stream:stream>");
+		session.conn.close();
+		component_listener.disconnect(session.conn, "stream error");
+	end
+end
+
+--- Component connlistener
+function component_listener.listener(conn, data)
+	local session = sessions[conn];
+	if not session then
+		local _send = conn.write;
+		session = { type = "component", conn = conn, send = function (data) return _send(tostring(data)); end };
+		sessions[conn] = session;
+
+		-- Logging functions --
+		
+		local conn_name = "xep114-"..tostring(conn):match("[a-f0-9]+$");
+		session.log = logger.init(conn_name);
+		session.close = session_close;
+		
+		session.log("info", "Incoming XEP-0114 connection");
+		
+		local parser = lxp.new(init_xmlhandlers(session, stream_callbacks), "|");
+		session.parser = parser;
+		
+		session.notopen = true;
+		
+		function session.data(conn, data)
+			local ok, err = parser:parse(data);
+			if ok then return; end
+			session:close("xml-not-well-formed");
+		end
+		
+		session.dispatch_stanza = stream_callbacks.handlestanza;
+		
+	end
+	if data then
+		session.data(conn, data);
+	end
+end
+	
+function component_listener.disconnect(conn, err)
+	local session = sessions[conn];
+	if session then
+		(session.log or log)("info", "component disconnected: %s (%s)", tostring(session.host), tostring(err));
+		if session.host then
+			if session.component then
+				deregister_component(session.host);
+			end
+		end
+		sessions[conn]  = nil;
+		session = nil;
+		collectgarbage("collect");
+	end
+end
+
+connlisteners.register('component', component_listener);
+
+module:add_event_hook("server-starting", function () connlisteners.start("component"); end);