Diff

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/plugins/mod_proxy65.lua	Sun Nov 22 14:58:09 2009 +0000
@@ -0,0 +1,268 @@
+-- Copyright (C) 2009 Thilo Cestonaro
+-- 
+-- This project is MIT/X11 licensed. Please see the
+-- COPYING file in the source package for more information.
+--
+--[[
+* to restart the proxy in the console: e.g.
+module:unload("proxy65");
+> server.removeserver(<proxy65_port>);
+module:load("proxy65", <proxy65_jid>);
+]]--
+
+if module:get_host_type() ~= "component" then
+	error("proxy65 should be loaded as a component, please see http://prosody.im/doc/components", 0);
+end
+
+local jid_split = require "util.jid".split;
+local st = require "util.stanza";
+local componentmanager = require "core.componentmanager";
+local config_get = require "core.configmanager".get;
+local connlisteners = require "net.connlisteners";
+local sha1 = require "util.hashes".sha1;
+
+local host, name = module:get_host(), "SOCKS5 Bytestreams Service";
+local sessions, transfers, component, replies_cache = {}, {}, nil, {};
+
+local proxy_port = config_get(host, "core", "proxy65_port") or 5000;
+local proxy_interface = config_get(host, "core", "proxy65_interface") or "*";
+local proxy_address = config_get(host, "core", "proxy65_address") or (proxy_interface ~= "*" and proxy_interface) or host;
+local proxy_acl = config_get(host, "core", "proxy65_acl");
+
+local connlistener = { default_port = proxy_port, default_interface = proxy_interface, default_mode = "*a" };
+
+function connlistener.listener(conn, data)
+	local session = sessions[conn] or {};
+	
+	if session.setup == nil and data ~= nil and data:sub(1):byte() == 0x05 and data:len() > 2 then
+		local nmethods = data:sub(2):byte();
+		local methods = data:sub(3);
+		local supported = false;
+		for i=1, nmethods, 1 do
+			if(methods:sub(i):byte() == 0x00) then -- 0x00 == method: NO AUTH
+				supported = true;
+				break;
+			end
+		end
+		if(supported) then
+			module:log("debug", "new session found ... ")
+			session.setup = true;
+			sessions[conn] = session;
+			conn.write(string.char(5, 0));
+		end
+		return;
+	end
+	if session.setup then
+		if session.sha ~= nil and transfers[session.sha] ~= nil then
+			local sha = session.sha;
+			if transfers[sha].activated == true and transfers[sha].initiator == conn and transfers[sha].target ~= nil then
+				transfers[sha].target.write(data);
+				return;
+			end
+		end
+		if data ~= nil and data:len() == 0x2F and  -- 40 == length of SHA1 HASH, and 7 other bytes => 47 => 0x2F
+			data:sub(1):byte() == 0x05 and -- SOCKS5 has 5 in first byte
+			data:sub(2):byte() == 0x01 and -- CMD must be 1
+			data:sub(3):byte() == 0x00 and -- RSV must be 0
+			data:sub(4):byte() == 0x03 and -- ATYP must be 3
+			data:sub(5):byte() == 40 and -- SHA1 HASH length must be 40 (0x28)
+			data:sub(-2):byte() == 0x00 and -- PORT must be 0, size 2 byte
+			data:sub(-1):byte() == 0x00 		
+		then
+			local sha = data:sub(6, 45); -- second param is not count! it's the ending index (included!)
+			if transfers[sha] == nil then
+				transfers[sha] = {};
+				transfers[sha].activated = false;
+				transfers[sha].target = conn;
+				session.sha = sha;
+				module:log("debug", "target connected ... ");
+			elseif transfers[sha].target ~= nil then
+				transfers[sha].initiator = conn;
+				session.sha = sha;
+				module:log("debug", "initiator connected ... ");
+			end
+			conn.write(string.char(5, 0, 0, 3, sha:len()) .. sha .. string.char(0, 0)); -- VER, REP, RSV, ATYP, BND.ADDR (sha), BND.PORT (2 Byte)
+		else
+			log:module("warn", "Neither data transfer nor initial connect of a participator of a transfer.")
+			conn.close();
+		end
+	else
+		if data ~= nil then
+			module:log("warn", "unknown connection with no authentication data -> closing it");
+			conn.close();
+		end
+	end
+end
+
+function connlistener.disconnect(conn, err)
+	local session = sessions[conn];
+	if session then
+		if session.sha and transfers[session.sha] then
+			local initiator, target = transfers[session.sha].initiator, transfers[session.sha].target;
+			if initiator == conn and target ~= nil then
+				target.close();
+			elseif target == conn and initiator ~= nil then
+			 	initiator.close();
+			end
+			transfers[session.sha] = nil;
+		end
+		-- Clean up any session-related stuff here
+		sessions[conn] = nil;
+	end
+end
+
+local function get_disco_info(stanza)
+	local reply = replies_cache.disco_info;
+	if reply == nil then
+	 	reply = st.iq({type='result', from=host}):query("http://jabber.org/protocol/disco#info")
+			:tag("identity", {category='proxy', type='bytestreams', name=name}):up()
+			:tag("feature", {var="http://jabber.org/protocol/bytestreams"});
+		replies_cache.disco_info = reply;
+	end
+
+	reply.attr.id = stanza.attr.id;
+	reply.attr.to = stanza.attr.from;
+	return reply;
+end
+
+local function get_disco_items(stanza)
+	local reply = replies_cache.disco_items;
+	if reply == nil then
+	 	reply = st.iq({type='result', from=host}):query("http://jabber.org/protocol/disco#items");
+		replies_cache.disco_items = reply;
+	end
+	
+	reply.attr.id = stanza.attr.id;
+	reply.attr.to = stanza.attr.from;
+	return reply;
+end
+
+local function _jid_join(node, host, resource)
+	local ret = host;
+	if ret then
+		if node then
+			ret = node .. "@" .. ret;
+		end
+		if resource then
+			ret = ret .. "/" .. resource;
+		end
+	end
+	return ret;
+end
+
+local function get_stream_host(origin, stanza)
+	local reply = replies_cache.stream_host;
+	local err_reply = replies_cache.stream_host_err;
+	local sid = stanza.tags[1].attr.sid;
+	local allow = false;
+	local jid_node, jid_host, jid_resource = jid_split(stanza.attr.from);
+	
+	if stanza.attr.from == nil then
+		jid_node = origin.username;
+		jid_host = origin.host;
+		jid_resource = origin.resource;
+	end
+	
+	if proxy_acl and #proxy_acl > 0 then
+		if host ~= nil then -- at least a domain is needed.
+			for _, acl in ipairs(proxy_acl) do
+				local acl_node, acl_host, acl_resource = jid_split(acl);
+				if ((acl_node ~= nil and acl_node == jid_node) or acl_node == nil) and
+				   ((acl_host ~= nil and acl_host == jid_host) or acl_host == nil) and
+				   ((acl_resource ~= nil and acl_resource == jid_resource) or acl_resource == nil) then
+					allow = true;
+				end
+			end
+		end
+	else
+		allow = true;
+	end
+	if allow == true then
+		if reply == nil then
+			reply = st.iq({type="result", from=host})
+				:query("http://jabber.org/protocol/bytestreams")
+				:tag("streamhost", {jid=host, host=proxy_address, port=proxy_port});
+			replies_cache.stream_host = reply;
+		end
+	else
+		module:log("warn", "Denying use of proxy for %s", tostring(_jid_join(jid_node, jid_host, jid_resource)));
+		if err_reply == nil then
+			err_reply = st.iq({type="error", from=host})
+				:query("http://jabber.org/protocol/bytestreams")
+				:tag("error", {code='403', type='auth'})
+				:tag("forbidden", {xmlns='urn:ietf:params:xml:ns:xmpp-stanzas'});
+			replies_cache.stream_host_err = err_reply;
+		end
+		reply = err_reply;
+	end
+	reply.attr.id = stanza.attr.id;
+	reply.attr.to = stanza.attr.from;
+	reply.tags[1].attr.sid = sid;
+	return reply;
+end
+
+module.unload = function()
+	componentmanager.deregister_component(host);
+	connlisteners.deregister(module.host .. ':proxy65');
+end
+
+local function set_activation(stanza)
+	local from, to, sid, reply = nil;
+	from = stanza.attr.from;
+	if stanza.tags[1] ~= nil and tostring(stanza.tags[1].name) == "query" then
+		if stanza.tags[1].attr ~= nil then
+			sid = stanza.tags[1].attr.sid;
+		end
+		if stanza.tags[1].tags[1] ~= nil and tostring(stanza.tags[1].tags[1].name) == "activate" then
+			to = stanza.tags[1].tags[1][1];
+		end
+	end
+	if from ~= nil and to ~= nil and sid ~= nil then
+		reply = st.iq({type="result", from=host, to=from});
+		reply.attr.id = stanza.attr.id;
+	end
+	return reply, from, to, sid;
+end
+
+function handle_to_domain(origin, stanza)
+	local to_node, to_host, to_resource = jid_split(stanza.attr.to);
+	if to_node == nil then
+		local type = stanza.attr.type;
+		if type == "error" or type == "result" then return; end
+		if stanza.name == "iq" and type == "get" then
+			local xmlns = stanza.tags[1].attr.xmlns
+			if xmlns == "http://jabber.org/protocol/disco#info" then
+				origin.send(get_disco_info(stanza));
+				return true;
+			elseif xmlns == "http://jabber.org/protocol/disco#items" then
+				origin.send(get_disco_items(stanza));
+				return true;
+			elseif xmlns == "http://jabber.org/protocol/bytestreams" then
+				origin.send(get_stream_host(origin, stanza));
+				return true;
+			end
+		elseif stanza.name == "iq" and type == "set" then
+			local reply, from, to, sid = set_activation(stanza);
+			if reply ~= nil and from ~= nil and to ~= nil and sid ~= nil then
+				local sha = sha1(sid .. from .. to, true);
+				if transfers[sha] == nil then
+					module:log("error", "transfers[sha]: nil");
+				elseif(transfers[sha] ~= nil and transfers[sha].initiator ~= nil and transfers[sha].target ~= nil) then
+					origin.send(reply);
+					transfers[sha].activated = true;
+				end
+			else
+				module:log("error", "activation failed: sid: %s, initiator: %s, target: %s", tostring(sid), tostring(from), tostring(to));
+			end
+		end
+	end
+	return;
+end
+
+if not connlisteners.register(module.host .. ':proxy65', connlistener) then
+	error("mod_proxy65: Could not establish a connection listener. Check your configuration please.");
+	error(" one possible cause for this would be that two proxy65 components share the same port.");
+end
+
+connlisteners.start(module.host .. ':proxy65');
+component = componentmanager.register_component(host, handle_to_domain);