plugins/mod_proxy65.lua

   1 -- Copyright (C) 2009 Thilo Cestonaro
   2 --
   3 -- This project is MIT/X11 licensed. Please see the
   4 -- COPYING file in the source package for more information.
   5 --
   6 --[[
   7 * to restart the proxy in the console: e.g.
   8 module:unload("proxy65");
   9 > server.removeserver(<proxy65_port>);
  10 module:load("proxy65", <proxy65_jid>);
  11 ]]--
  12
  13 if module:get_host_type() ~= "component" then
  14         error("proxy65 should be loaded as a component, please see http://prosody.im/doc/components", 0);
  15 end
  16
  17 local jid_split, jid_join, jid_compare = require "util.jid".split, require "util.jid".join, require "util.jid".compare;
  18 local st = require "util.stanza";
  19 local connlisteners = require "net.connlisteners";
  20 local sha1 = require "util.hashes".sha1;
  21 local server = require "net.server";
  22
  23 local host, name = module:get_host(), "SOCKS5 Bytestreams Service";
  24 local sessions, transfers, component, replies_cache = {}, {}, nil, {};
  25
  26 local proxy_port = module:get_option("proxy65_port") or 5000;
  27 local proxy_interface = module:get_option("proxy65_interface") or "*";
  28 local proxy_address = module:get_option("proxy65_address") or (proxy_interface ~= "*" and proxy_interface) or host;
  29 local proxy_acl = module:get_option("proxy65_acl");
  30 local max_buffer_size = 4096;
  31
  32 local connlistener = { default_port = proxy_port, default_interface = proxy_interface, default_mode = "*a" };
  33
  34 function connlistener.onincoming(conn, data)
  35         local session = sessions[conn] or {};
  36
  37         if session.setup == nil and data ~= nil and data:sub(1):byte() == 0x05 and data:len() > 2 then
  38                 local nmethods = data:sub(2):byte();
  39                 local methods = data:sub(3);
  40                 local supported = false;
  41                 for i=1, nmethods, 1 do
  42                         if(methods:sub(i):byte() == 0x00) then -- 0x00 == method: NO AUTH
  43                                 supported = true;
  44                                 break;
  45                         end
  46                 end
  47                 if(supported) then
  48                         module:log("debug", "new session found ... ")
  49                         session.setup = true;
  50                         sessions[conn] = session;
  51                         conn:write(string.char(5, 0));
  52                 end
  53                 return;
  54         end
  55         if session.setup then
  56                 if session.sha ~= nil and transfers[session.sha] ~= nil then
  57                         local sha = session.sha;
  58                         if transfers[sha].activated == true and transfers[sha].target ~= nil then
  59                                 if  transfers[sha].initiator == conn then
  60                                         transfers[sha].target:write(data);
  61                                 else
  62                                         transfers[sha].initiator:write(data);
  63                                 end
  64                                 return;
  65                         end
  66                 end
  67                 if data ~= nil and data:len() == 0x2F and  -- 40 == length of SHA1 HASH, and 7 other bytes => 47 => 0x2F
  68                         data:sub(1):byte() == 0x05 and -- SOCKS5 has 5 in first byte
  69                         data:sub(2):byte() == 0x01 and -- CMD must be 1
  70                         data:sub(3):byte() == 0x00 and -- RSV must be 0
  71                         data:sub(4):byte() == 0x03 and -- ATYP must be 3
  72                         data:sub(5):byte() == 40 and -- SHA1 HASH length must be 40 (0x28)
  73                         data:sub(-2):byte() == 0x00 and -- PORT must be 0, size 2 byte
  74                         data:sub(-1):byte() == 0x00
  75                 then
  76                         local sha = data:sub(6, 45); -- second param is not count! it's the ending index (included!)
  77                         if transfers[sha] == nil then
  78                                 transfers[sha] = {};
  79                                 transfers[sha].activated = false;
  80                                 transfers[sha].target = conn;
  81                                 session.sha = sha;
  82                                 module:log("debug", "target connected ... ");
  83                         elseif transfers[sha].target ~= nil then
  84                                 transfers[sha].initiator = conn;
  85                                 session.sha = sha;
  86                                 module:log("debug", "initiator connected ... ");
  87                                 server.link(conn, transfers[sha].target, max_buffer_size);
  88                                 server.link(transfers[sha].target, conn, max_buffer_size);
  89                         end
  90                         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)
  91                         conn:lock_read(true)
  92                 else
  93                         module:log("warn", "Neither data transfer nor initial connect of a participator of a transfer.")
  94                         conn:close();
  95                 end
  96         else
  97                 if data ~= nil then
  98                         module:log("warn", "unknown connection with no authentication data -> closing it");
  99                         conn:close();
 100                 end
 101         end
 102 end
 103
 104 function connlistener.ondisconnect(conn, err)
 105         local session = sessions[conn];
 106         if session then
 107                 if session.sha and transfers[session.sha] then
 108                         local initiator, target = transfers[session.sha].initiator, transfers[session.sha].target;
 109                         if initiator == conn and target ~= nil then
 110                                 target:close();
 111                         elseif target == conn and initiator ~= nil then
 112                                 initiator:close();
 113                         end
 114                         transfers[session.sha] = nil;
 115                 end
 116                 -- Clean up any session-related stuff here
 117                 sessions[conn] = nil;
 118         end
 119 end
 120
 121 module:hook("iq-get/host/http://jabber.org/protocol/disco#info:query", function(event)
 122         local origin, stanza = event.origin, event.stanza;
 123         local reply = replies_cache.disco_info;
 124         if reply == nil then
 125                 reply = st.iq({type='result', from=host}):query("http://jabber.org/protocol/disco#info")
 126                         :tag("identity", {category='proxy', type='bytestreams', name=name}):up()
 127                         :tag("feature", {var="http://jabber.org/protocol/bytestreams"});
 128                 replies_cache.disco_info = reply;
 129         end
 130
 131         reply.attr.id = stanza.attr.id;
 132         reply.attr.to = stanza.attr.from;
 133         origin.send(reply);
 134         return true;
 135 end, -1);
 136
 137 module:hook("iq-get/host/http://jabber.org/protocol/disco#items:query", function(event)
 138         local origin, stanza = event.origin, event.stanza;
 139         local reply = replies_cache.disco_items;
 140         if reply == nil then
 141                 reply = st.iq({type='result', from=host}):query("http://jabber.org/protocol/disco#items");
 142                 replies_cache.disco_items = reply;
 143         end
 144
 145         reply.attr.id = stanza.attr.id;
 146         reply.attr.to = stanza.attr.from;
 147         origin.send(reply);
 148         return true;
 149 end, -1);
 150
 151 module:hook("iq-get/host/http://jabber.org/protocol/bytestreams:query", function(event)
 152         local origin, stanza = event.origin, event.stanza;
 153         local reply = replies_cache.stream_host;
 154         local err_reply = replies_cache.stream_host_err;
 155         local sid = stanza.tags[1].attr.sid;
 156         local allow = false;
 157         local jid = stanza.attr.from;
 158
 159         if proxy_acl and #proxy_acl > 0 then
 160                 for _, acl in ipairs(proxy_acl) do
 161                         if jid_compare(jid, acl) then allow = true; end
 162                 end
 163         else
 164                 allow = true;
 165         end
 166         if allow == true then
 167                 if reply == nil then
 168                         reply = st.iq({type="result", from=host})
 169                                 :query("http://jabber.org/protocol/bytestreams")
 170                                 :tag("streamhost", {jid=host, host=proxy_address, port=proxy_port});
 171                         replies_cache.stream_host = reply;
 172                 end
 173         else
 174                 module:log("warn", "Denying use of proxy for %s", tostring(jid));
 175                 if err_reply == nil then
 176                         err_reply = st.iq({type="error", from=host})
 177                                 :query("http://jabber.org/protocol/bytestreams")
 178                                 :tag("error", {code='403', type='auth'})
 179                                 :tag("forbidden", {xmlns='urn:ietf:params:xml:ns:xmpp-stanzas'});
 180                         replies_cache.stream_host_err = err_reply;
 181                 end
 182                 reply = err_reply;
 183         end
 184         reply.attr.id = stanza.attr.id;
 185         reply.attr.to = stanza.attr.from;
 186         reply.tags[1].attr.sid = sid;
 187         origin.send(reply);
 188         return true;
 189 end);
 190
 191 module.unload = function()
 192         connlisteners.deregister(module.host .. ':proxy65');
 193 end
 194
 195 local function set_activation(stanza)
 196         local from, to, sid, reply = nil;
 197         from = stanza.attr.from;
 198         if stanza.tags[1] ~= nil and tostring(stanza.tags[1].name) == "query" then
 199                 if stanza.tags[1].attr ~= nil then
 200                         sid = stanza.tags[1].attr.sid;
 201                 end
 202                 if stanza.tags[1].tags[1] ~= nil and tostring(stanza.tags[1].tags[1].name) == "activate" then
 203                         to = stanza.tags[1].tags[1][1];
 204                 end
 205         end
 206         if from ~= nil and to ~= nil and sid ~= nil then
 207                 reply = st.iq({type="result", from=host, to=from});
 208                 reply.attr.id = stanza.attr.id;
 209         end
 210         return reply, from, to, sid;
 211 end
 212
 213 module:hook("iq-set/host/http://jabber.org/protocol/bytestreams:query", function(event)
 214         local origin, stanza = event.origin, event.stanza;
 215
 216         module:log("debug", "Received activation request from %s", stanza.attr.from);
 217         local reply, from, to, sid = set_activation(stanza);
 218         if reply ~= nil and from ~= nil and to ~= nil and sid ~= nil then
 219                 local sha = sha1(sid .. from .. to, true);
 220                 if transfers[sha] == nil then
 221                         module:log("error", "transfers[sha]: nil");
 222                 elseif(transfers[sha] ~= nil and transfers[sha].initiator ~= nil and transfers[sha].target ~= nil) then
 223                         origin.send(reply);
 224                         transfers[sha].activated = true;
 225                         transfers[sha].target:lock_read(false);
 226                         transfers[sha].initiator:lock_read(false);
 227                 else
 228                         module:log("debug", "Both parties were not yet connected");
 229                         local message = "Neither party is connected to the proxy";
 230                         if transfers[sha].initiator then
 231                                 message = "The recipient is not connected to the proxy";
 232                         elseif transfers[sha].target then
 233                                 message = "The sender (you) is not connected to the proxy";
 234                         end
 235                         origin.send(st.error_reply(stanza, "cancel", "not-allowed", message));
 236                 end
 237                 return true;
 238         else
 239                 module:log("error", "activation failed: sid: %s, initiator: %s, target: %s", tostring(sid), tostring(from), tostring(to));
 240         end
 241 end);
 242
 243 if not connlisteners.register(module.host .. ':proxy65', connlistener) then
 244         module:log("error", "mod_proxy65: Could not establish a connection listener. Check your configuration please.");
 245         module:log("error", "Possibly two proxy65 components are configured to share the same port.");
 246 end
 247
 248 connlisteners.start(module.host .. ':proxy65');