plugins/mod_proxy65.lua

   1 -- Prosody IM
   2 -- Copyright (C) 2008-2011 Matthew Wild
   3 -- Copyright (C) 2008-2011 Waqas Hussain
   4 -- Copyright (C) 2009 Thilo Cestonaro
   5 --
   6 -- This project is MIT/X11 licensed. Please see the
   7 -- COPYING file in the source package for more information.
   8 --
   9
  10 module:set_global();
  11
  12 local jid_compare, jid_prep = require "util.jid".compare, require "util.jid".prep;
  13 local st = require "util.stanza";
  14 local sha1 = require "util.hashes".sha1;
  15 local b64 = require "util.encodings".base64.encode;
  16 local server = require "net.server";
  17 local portmanager = require "core.portmanager";
  18
  19 local sessions, transfers = module:shared("sessions", "transfers");
  20 local max_buffer_size = 4096;
  21
  22 local listener = {};
  23
  24 function listener.onincoming(conn, data)
  25         local session = sessions[conn] or {};
  26
  27         local transfer = transfers[session.sha];
  28         if transfer and transfer.activated then -- copy data between initiator and target
  29                 local initiator, target = transfer.initiator, transfer.target;
  30                 (conn == initiator and target or initiator):write(data);
  31                 return;
  32         end -- FIXME server.link should be doing this?
  33
  34         if not session.greeting_done then
  35                 local nmethods = data:byte(2) or 0;
  36                 if data:byte(1) == 0x05 and nmethods > 0 and #data == 2 + nmethods then -- check if we have all the data
  37                         if data:find("%z") then -- 0x00 = 'No authentication' is supported
  38                                 session.greeting_done = true;
  39                                 sessions[conn] = session;
  40                                 conn:write("\5\0"); -- send (SOCKS version 5, No authentication)
  41                                 module:log("debug", "SOCKS5 greeting complete");
  42                                 return;
  43                         end
  44                 end -- else error, unexpected input
  45                 conn:write("\5\255"); -- send (SOCKS version 5, no acceptable method)
  46                 conn:close();
  47                 module:log("debug", "Invalid SOCKS5 greeting recieved: '%s'", b64(data));
  48         else -- connection request
  49                 --local head = string.char( 0x05, 0x01, 0x00, 0x03, 40 ); -- ( VER=5=SOCKS5, CMD=1=CONNECT, RSV=0=RESERVED, ATYP=3=DOMAIMNAME, SHA-1 size )
  50                 if #data == 47 and data:sub(1,5) == "\5\1\0\3\40" and data:sub(-2) == "\0\0" then
  51                         local sha = data:sub(6, 45);
  52                         conn:pause();
  53                         conn:write("\5\0\0\3\40" .. sha .. "\0\0"); -- VER, REP, RSV, ATYP, BND.ADDR (sha), BND.PORT (2 Byte)
  54                         if not transfers[sha] then
  55                                 transfers[sha] = {};
  56                                 transfers[sha].target = conn;
  57                                 session.sha = sha;
  58                                 module:log("debug", "SOCKS5 target connected for session %s", sha);
  59                         else -- transfers[sha].target ~= nil
  60                                 transfers[sha].initiator = conn;
  61                                 session.sha = sha;
  62                                 module:log("debug", "SOCKS5 initiator connected for session %s", sha);
  63                                 server.link(conn, transfers[sha].target, max_buffer_size);
  64                                 server.link(transfers[sha].target, conn, max_buffer_size);
  65                         end
  66                 else -- error, unexpected input
  67                         conn:write("\5\1\0\3\0\0\0"); -- VER, REP, RSV, ATYP, BND.ADDR (sha), BND.PORT (2 Byte)
  68                         conn:close();
  69                         module:log("debug", "Invalid SOCKS5 negotiation recieved: '%s'", b64(data));
  70                 end
  71         end
  72 end
  73
  74 function listener.ondisconnect(conn, err)
  75         local session = sessions[conn];
  76         if session then
  77                 if transfers[session.sha] then
  78                         local initiator, target = transfers[session.sha].initiator, transfers[session.sha].target;
  79                         if initiator == conn and target ~= nil then
  80                                 target:close();
  81                         elseif target == conn and initiator ~= nil then
  82                                 initiator:close();
  83                         end
  84                         transfers[session.sha] = nil;
  85                 end
  86                 -- Clean up any session-related stuff here
  87                 sessions[conn] = nil;
  88         end
  89 end
  90
  91 function module.add_host(module)
  92         local host, name = module:get_host(), module:get_option_string("name", "SOCKS5 Bytestreams Service");
  93
  94         local proxy_address = module:get_option_string("proxy65_address", host);
  95         local proxy_port = next(portmanager.get_active_services():search("proxy65", nil)[1] or {});
  96         local proxy_acl = module:get_option_array("proxy65_acl");
  97
  98         -- COMPAT w/pre-0.9 where proxy65_port was specified in the components section of the config
  99         local legacy_config = module:get_option_number("proxy65_port");
 100         if legacy_config then
 101                 module:log("warn", "proxy65_port is deprecated, please put proxy65_ports = { %d } into the global section instead", legacy_config);
 102         end
 103
 104         module:depends("disco");
 105         module:add_identity("proxy", "bytestreams", name);
 106         module:add_feature("http://jabber.org/protocol/bytestreams");
 107
 108         module:hook("iq-get/host/http://jabber.org/protocol/bytestreams:query", function(event)
 109                 local origin, stanza = event.origin, event.stanza;
 110
 111                 -- check ACL
 112                 while proxy_acl and #proxy_acl > 0 do -- using 'while' instead of 'if' so we can break out of it
 113                         local jid = stanza.attr.from;
 114                         local allow;
 115                         for _, acl in ipairs(proxy_acl) do
 116                                 if jid_compare(jid, acl) then allow = true; break; end
 117                         end
 118                         if allow then break; end
 119                         module:log("warn", "Denying use of proxy for %s", tostring(stanza.attr.from));
 120                         origin.send(st.error_reply(stanza, "auth", "forbidden"));
 121                         return true;
 122                 end
 123
 124                 local sid = stanza.tags[1].attr.sid;
 125                 origin.send(st.reply(stanza):tag("query", {xmlns="http://jabber.org/protocol/bytestreams", sid=sid})
 126                         :tag("streamhost", {jid=host, host=proxy_address, port=proxy_port}));
 127                 return true;
 128         end);
 129
 130         module:hook("iq-set/host/http://jabber.org/protocol/bytestreams:query", function(event)
 131                 local origin, stanza = event.origin, event.stanza;
 132
 133                 local query = stanza.tags[1];
 134                 local sid = query.attr.sid;
 135                 local from = stanza.attr.from;
 136                 local to = query:get_child_text("activate");
 137                 local prepped_to = jid_prep(to);
 138
 139                 local info = "sid: "..tostring(sid)..", initiator: "..tostring(from)..", target: "..tostring(prepped_to or to);
 140                 if prepped_to and sid then
 141                         local sha = sha1(sid .. from .. prepped_to, true);
 142                         if not transfers[sha] then
 143                                 module:log("debug", "Activation request has unknown session id; activation failed (%s)", info);
 144                                 origin.send(st.error_reply(stanza, "modify", "item-not-found"));
 145                         elseif not transfers[sha].initiator then
 146                                 module:log("debug", "The sender was not connected to the proxy; activation failed (%s)", info);
 147                                 origin.send(st.error_reply(stanza, "cancel", "not-allowed", "The sender (you) is not connected to the proxy"));
 148                         --elseif not transfers[sha].target then -- can't happen, as target is set when a transfer object is created
 149                         --      module:log("debug", "The recipient was not connected to the proxy; activation failed (%s)", info);
 150                         --      origin.send(st.error_reply(stanza, "cancel", "not-allowed", "The recipient is not connected to the proxy"));
 151                         else -- if transfers[sha].initiator ~= nil and transfers[sha].target ~= nil then
 152                                 module:log("debug", "Transfer activated (%s)", info);
 153                                 transfers[sha].activated = true;
 154                                 transfers[sha].target:resume();
 155                                 transfers[sha].initiator:resume();
 156                                 origin.send(st.reply(stanza));
 157                         end
 158                 elseif to and sid then
 159                         module:log("debug", "Malformed activation jid; activation failed (%s)", info);
 160                         origin.send(st.error_reply(stanza, "modify", "jid-malformed"));
 161                 else
 162                         module:log("debug", "Bad request; activation failed (%s)", info);
 163                         origin.send(st.error_reply(stanza, "modify", "bad-request"));
 164                 end
 165                 return true;
 166         end);
 167 end
 168
 169 module:provides("net", {
 170         default_port = 5000;
 171         listener = listener;
 172         multiplex = {
 173                 pattern = "^\5";
 174         };
 175 });