# HG changeset patch
# User Matthew Wild <mwild1@gmail.com>
# Date 1282400888 -3600
# Node ID 9c5362d393f08d4f6ff79d90d7b001080c0c7f14
# Parent  e45883a3f39a2c01b93dc7b75cb1d4095365b857
verse.plugins.jingle_s5b: Jingle SOCKS5 Bytestreams transport

diff -r e45883a3f39a -r 9c5362d393f0 plugins/jingle_s5b.lua
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/plugins/jingle_s5b.lua	Sat Aug 21 15:28:08 2010 +0100
@@ -0,0 +1,215 @@
+
+local xmlns_s5b = "urn:xmpp:jingle:transports:s5b:1";
+local sha1 = require "util.sha1".sha1;
+local uuid_generate = require "util.uuid".generate;
+
+local function negotiate_socks5(conn, hash)
+	local function suppress_connected()
+		conn:unhook("connected", suppress_connected);
+		return true;
+	end
+	local function receive_connection_response(data)
+		conn:unhook("incoming-raw", receive_connection_response);
+		
+		if data:sub(1, 2) ~= "\005\000" then
+			return conn:event("error", "connection-failure");
+		end
+		conn:event("connected");
+		return true;
+	end
+	local function receive_auth_response(data)
+		conn:unhook("incoming-raw", receive_auth_response);
+		if data ~= "\005\000" then -- SOCKSv5; "NO AUTHENTICATION"
+			-- Server is not SOCKSv5, or does not allow no auth
+			local err = "version-mismatch";
+			if data:sub(1,1) == "\005" then
+				err = "authentication-failure";
+			end
+			return conn:event("error", err);
+		end
+		-- Request SOCKS5 connection
+		conn:send(string.char(0x05, 0x01, 0x00, 0x03, #hash)..hash.."\0\0"); --FIXME: Move to "connected"?
+		conn:hook("incoming-raw", receive_connection_response, 100);
+		return true;
+	end
+	conn:hook("connected", suppress_connected, 200);
+	conn:hook("incoming-raw", receive_auth_response, 100);
+	conn:send("\005\001\000"); -- SOCKSv5; 1 mechanism; "NO AUTHENTICATION"
+end
+
+local function connect_to_usable_streamhost(callback, streamhosts, auth_token)
+	local conn = verse.new(nil, {
+		streamhosts = streamhosts,
+		current_host = 0;
+	});
+	--Attempt to connect to the next host
+	local function attempt_next_streamhost(event)
+		if event then
+			return callback(nil, event.reason); 
+		end
+		-- First connect, or the last connect failed
+		if conn.current_host < #conn.streamhosts then
+			conn.current_host = conn.current_host + 1;
+			conn:debug("Attempting to connect to "..conn.streamhosts[conn.current_host].host..":"..conn.streamhosts[conn.current_host].port.."...");
+			local ok, err = conn:connect(
+				conn.streamhosts[conn.current_host].host,
+				conn.streamhosts[conn.current_host].port
+			);
+			if not ok then
+				conn:debug("Error connecting to proxy (%s:%s): %s", 
+					conn.streamhosts[conn.current_host].host,
+					conn.streamhosts[conn.current_host].port,
+					err
+				);
+			else
+				conn:debug("Connecting...");
+			end
+			negotiate_socks5(conn, auth_token);
+			return true; -- Halt processing of disconnected event
+		end
+		-- All streamhosts tried, none successful
+		conn:unhook("disconnected", attempt_next_streamhost);
+		return callback(nil);
+		-- Let disconnected event fall through to user handlers...
+	end
+	conn:hook("disconnected", attempt_next_streamhost, 100);
+	-- When this event fires, we're connected to a streamhost
+	conn:hook("connected", function ()
+		conn:unhook("disconnected", attempt_next_streamhost);
+		callback(conn.streamhosts[conn.current_host], conn);
+	end, 100);
+	attempt_next_streamhost(); -- Set it in motion
+	return conn;
+end
+
+function verse.plugins.jingle_s5b(stream)
+	stream:hook("ready", function ()
+		stream:add_disco_feature(xmlns_s5b);
+	end, 10);
+
+	local s5b = {};
+	
+	function s5b:generate_initiate()
+		self.s5b_sid = uuid_generate();
+		local transport = verse.stanza("transport", { xmlns = xmlns_s5b,
+			mode = "tcp", sid = self.s5b_sid });
+		local p = 0;
+		for jid, streamhost in pairs(stream.proxy65.available_streamhosts) do
+			p = p + 1;
+			transport:tag("candidate", { jid = jid, host = streamhost.host,
+				port = streamhost.port, cid=jid, priority = p, type = "proxy" }):up();
+		end
+		stream:debug("Have %d proxies", p)
+		return transport;
+	end
+	
+	function s5b:generate_accept(initiate_transport)
+		local candidates = {};
+		self.s5b_peer_candidates = candidates;
+		self.s5b_mode = initiate_transport.attr.mode or "tcp";
+		self.s5b_sid = initiate_transport.attr.sid or self.jingle.sid;
+		
+		-- Import the list of candidates the initiator offered us
+		for candidate in initiate_transport:childtags() do
+			--if candidate.attr.jid == "asterix4@jabber.lagaule.org/Gajim"
+			--and candidate.attr.host == "82.246.25.239" then
+				candidates[candidate.attr.cid] = {
+					type = candidate.attr.type;
+					jid = candidate.attr.jid;
+					host = candidate.attr.host;
+					port = tonumber(candidate.attr.port) or 0;
+					priority = tonumber(candidate.attr.priority) or 0;
+					cid = candidate.attr.cid;
+				};
+			--end
+		end
+		
+		-- Import our own candidates
+		-- TODO ^
+		local transport = verse.stanza("transport", { xmlns = xmlns_s5b });
+		return transport;
+	end
+	
+	function s5b:connect(callback)
+		stream:warn("Connecting!");
+		
+		local streamhost_array = {};
+		for cid, streamhost in pairs(self.s5b_peer_candidates or {}) do
+			streamhost_array[#streamhost_array+1] = streamhost;
+		end
+		
+		if #streamhost_array > 0 then
+			self.connecting_peer_candidates = true;
+			local function onconnect(streamhost, conn)
+				self.jingle:send_command("transport-info", verse.stanza("transport", { xmlns = xmlns_s5b, sid = self.s5b_sid })
+					:tag("candidate-used", { cid = streamhost.cid }));
+				self.onconnect_callback = callback;
+				self.conn = conn;
+			end
+			local auth_token = sha1(self.s5b_sid..self.peer..stream.jid, true);
+			connect_to_usable_streamhost(onconnect, streamhost_array, auth_token);
+		else
+			stream:warn("Actually, I'm going to wait for my peer to tell me its streamhost...");
+			self.onconnect_callback = callback;
+		end
+	end
+	
+	function s5b:info_received(jingle_tag)
+		stream:warn("Info received");
+		local transport_tag = jingle_tag:child_with_name("content"):child_with_name("transport");
+		if transport_tag:get_child("candidate-used") and not self.connecting_peer_candidates then
+			local candidate_used = transport_tag:child_with_name("candidate-used");
+			if candidate_used then
+				-- Connect straight away to candidate used, we weren't trying any anyway
+				local function onconnect(streamhost, conn)
+					if self.jingle.role == "initiator" then -- More correct would be - "is this a candidate we offered?"
+						-- Activate the stream
+						self.jingle.stream:send_iq(verse.iq({ to = streamhost.jid, type = "set" })
+							:tag("query", { xmlns = xmlns_bytestreams, sid = self.s5b_sid })
+								:tag("activate"):text(self.jingle.peer), function (result)
+							
+							if result.attr.type == "result" then
+								self.jingle:send_command("transport-info", verse.stanza("transport", { xmlns = xmlns_s5b, sid = self.s5b_sid })
+									:tag("activated", { cid = candidate_used.attr.cid }));
+								self.conn = conn;
+								self.onconnect_callback(conn);
+							else
+								self.jingle.stream:error("Failed to activate bytestream");
+							end
+						end);
+					end
+				end
+				
+				-- FIXME: Another assumption that cid==jid, and that it was our candidate
+				self.jingle.stream:debug("CID: %s", self.jingle.stream.proxy65.available_streamhosts[candidate_used.attr.cid]);
+				local streamhost_array = {
+					self.jingle.stream.proxy65.available_streamhosts[candidate_used.attr.cid];
+				};
+
+				local auth_token = sha1(self.s5b_sid..stream.jid..self.peer, true);
+				connect_to_usable_streamhost(onconnect, streamhost_array, auth_token);
+			end
+		elseif transport_tag:get_child("activated") then
+			self.onconnect_callback(self.conn);
+		end
+	end
+	
+	function s5b:disconnect()
+		if self.conn then
+			self.conn:close();
+		end
+	end
+	
+	function s5b:handle_accepted(jingle_tag)
+	end
+
+	local s5b_mt = { __index = s5b };
+	stream:hook("jingle/transport/"..xmlns_s5b, function (jingle)
+		return setmetatable({
+			role = jingle.role,
+			peer = jingle.peer,
+			stream = jingle.stream,
+			jingle = jingle,
+		}, s5b_mt);
+	end);
+end