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 config_get = require "core.configmanager".get;
  20 local connlisteners = require "net.connlisteners";
  21 local sha1 = require "util.hashes".sha1;
  22 local server = require "net.server";
  23
  24 local host, name = module:get_host(), "SOCKS5 Bytestreams Service";
  25 local sessions, transfers, component, replies_cache = {}, {}, nil, {};
  26
  27 local proxy_port = config_get(host, "core", "proxy65_port") or 5000;
  28 local proxy_interface = config_get(host, "core", "proxy65_interface") or "*";
  29 local proxy_address = config_get(host, "core", "proxy65_address") or (proxy_interface ~= "*" and proxy_interface) or host;
  30 local proxy_acl = config_get(host, "core", "proxy65_acl");
  31 local max_buffer_size = 4096;
  32
  33 local connlistener = { default_port = proxy_port, default_interface = proxy_interface, default_mode = "*a" };
  34
  35 function connlistener.onincoming(conn, data)
  36         local session = sessions[conn] or {};
  37
  38         if session.setup == nil and data ~= nil and data:sub(1):byte() == 0x05 and data:len() > 2 then
  39                 local nmethods = data:sub(2):byte();
  40                 local methods = data:sub(3);
  41                 local supported = false;
  42                 for i=1, nmethods, 1 do
  43                         if(methods:sub(i):byte() == 0x00) then -- 0x00 == method: NO AUTH
  44                                 supported = true;
  45                                 break;
  46                         end
  47                 end
  48                 if(supported) then
  49                         module:log("debug", "new session found ... ")
  50                         session.setup = true;
  51                         sessions[conn] = session;
  52                         conn:write(string.char(5, 0));
  53                 end
  54                 return;
  55         end
  56         if session.setup then
  57                 if session.sha ~= nil and transfers[session.sha] ~= nil then
  58                         local sha = session.sha;
  59                         if transfers[sha].activated == true and transfers[sha].target ~= nil then
  60                                 if  transfers[sha].initiator == conn then
  61                                         transfers[sha].target:write(data);
  62                                 else
  63                                         transfers[sha].initiator:write(data);
  64                                 end
  65                                 return;
  66                         end
  67                 end
  68                 if data ~= nil and data:len() == 0x2F and  -- 40 == length of SHA1 HASH, and 7 other bytes => 47 => 0x2F
  69                         data:sub(1):byte() == 0x05 and -- SOCKS5 has 5 in first byte
  70                         data:sub(2):byte() == 0x01 and -- CMD must be 1
  71                         data:sub(3):byte() == 0x00 and -- RSV must be 0
  72                         data:sub(4):byte() == 0x03 and -- ATYP must be 3
  73                         data:sub(5):byte() == 40 and -- SHA1 HASH length must be 40 (0x28)
  74                         data:sub(-2):byte() == 0x00 and -- PORT must be 0, size 2 byte
  75                         data:sub(-1):byte() == 0x00
  76                 then
  77                         local sha = data:sub(6, 45); -- second param is not count! it's the ending index (included!)
  78                         if transfers[sha] == nil then
  79                                 transfers[sha] = {};
  80                                 transfers[sha].activated = false;
  81                                 transfers[sha].target = conn;
  82                                 session.sha = sha;
  83                                 module:log("debug", "target connected ... ");
  84                         elseif transfers[sha].target ~= nil then
  85                                 transfers[sha].initiator = conn;
  86                                 session.sha = sha;
  87                                 module:log("debug", "initiator connected ... ");
  88                                 server.link(conn, transfers[sha].target, max_buffer_size);
  89                                 server.link(transfers[sha].target, conn, max_buffer_size);
  90                         end
  91                         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)
  92                         conn:lock_read(true)
  93                 else
  94                         module:log("warn", "Neither data transfer nor initial connect of a participator of a transfer.")
  95                         conn:close();
  96                 end
  97         else
  98                 if data ~= nil then
  99                         module:log("warn", "unknown connection with no authentication data -> closing it");
 100                         conn:close();
 101                 end
 102         end
 103 end
 104
 105 function connlistener.ondisconnect(conn, err)
 106         local session = sessions[conn];
 107         if session then
 108                 if session.sha and transfers[session.sha] then
 109                         local initiator, target = transfers[session.sha].initiator, transfers[session.sha].target;
 110                         if initiator == conn and target ~= nil then
 111                                 target:close();
 112                         elseif target == conn and initiator ~= nil then
 113                                 initiator:close();
 114                         end
 115                         transfers[session.sha] = nil;
 116                 end
 117                 -- Clean up any session-related stuff here
 118                 sessions[conn] = nil;
 119         end
 120 end
 121
 122 local function get_disco_info(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         return reply;
 134 end
 135
 136 local function get_disco_items(stanza)
 137         local reply = replies_cache.disco_items;
 138         if reply == nil then
 139                 reply = st.iq({type='result', from=host}):query("http://jabber.org/protocol/disco#items");
 140                 replies_cache.disco_items = reply;
 141         end
 142
 143         reply.attr.id = stanza.attr.id;
 144         reply.attr.to = stanza.attr.from;
 145         return reply;
 146 end
 147
 148 local function get_stream_host(origin, stanza)
 149         local reply = replies_cache.stream_host;
 150         local err_reply = replies_cache.stream_host_err;
 151         local sid = stanza.tags[1].attr.sid;
 152         local allow = false;
 153         local jid = stanza.attr.from;
 154
 155         if proxy_acl and #proxy_acl > 0 then
 156                 for _, acl in ipairs(proxy_acl) do
 157                         if jid_compare(jid, acl) then allow = true; end
 158                 end
 159         else
 160                 allow = true;
 161         end
 162         if allow == true then
 163                 if reply == nil then
 164                         reply = st.iq({type="result", from=host})
 165                                 :query("http://jabber.org/protocol/bytestreams")
 166                                 :tag("streamhost", {jid=host, host=proxy_address, port=proxy_port});
 167                         replies_cache.stream_host = reply;
 168                 end
 169         else
 170                 module:log("warn", "Denying use of proxy for %s", tostring(jid));
 171                 if err_reply == nil then
 172                         err_reply = st.iq({type="error", from=host})
 173                                 :query("http://jabber.org/protocol/bytestreams")
 174                                 :tag("error", {code='403', type='auth'})
 175                                 :tag("forbidden", {xmlns='urn:ietf:params:xml:ns:xmpp-stanzas'});
 176                         replies_cache.stream_host_err = err_reply;
 177                 end
 178                 reply = err_reply;
 179         end
 180         reply.attr.id = stanza.attr.id;
 181         reply.attr.to = stanza.attr.from;
 182         reply.tags[1].attr.sid = sid;
 183         return reply;
 184 end
 185
 186 module.unload = function()
 187         connlisteners.deregister(module.host .. ':proxy65');
 188 end
 189
 190 local function set_activation(stanza)
 191         local from, to, sid, reply = nil;
 192         from = stanza.attr.from;
 193         if stanza.tags[1] ~= nil and tostring(stanza.tags[1].name) == "query" then
 194                 if stanza.tags[1].attr ~= nil then
 195                         sid = stanza.tags[1].attr.sid;
 196                 end
 197                 if stanza.tags[1].tags[1] ~= nil and tostring(stanza.tags[1].tags[1].name) == "activate" then
 198                         to = stanza.tags[1].tags[1][1];
 199                 end
 200         end
 201         if from ~= nil and to ~= nil and sid ~= nil then
 202                 reply = st.iq({type="result", from=host, to=from});
 203                 reply.attr.id = stanza.attr.id;
 204         end
 205         return reply, from, to, sid;
 206 end
 207
 208 function handle_to_domain(event)
 209         local origin, stanza = event.origin, event.stanza;
 210         if stanza.attr.type == "get" then
 211                 local xmlns = stanza.tags[1].attr.xmlns
 212                 if xmlns == "http://jabber.org/protocol/disco#info" then
 213                         origin.send(get_disco_info(stanza));
 214                         return true;
 215                 elseif xmlns == "http://jabber.org/protocol/disco#items" then
 216                         origin.send(get_disco_items(stanza));
 217                         return true;
 218                 elseif xmlns == "http://jabber.org/protocol/bytestreams" then
 219                         origin.send(get_stream_host(origin, stanza));
 220                         return true;
 221                 else
 222                         origin.send(st.error_reply(stanza, "cancel", "service-unavailable"));
 223                         return true;
 224                 end
 225         else -- stanza.attr.type == "set"
 226                 module:log("debug", "Received activation request from %s", stanza.attr.from);
 227                 local reply, from, to, sid = set_activation(stanza);
 228                 if reply ~= nil and from ~= nil and to ~= nil and sid ~= nil then
 229                         local sha = sha1(sid .. from .. to, true);
 230                         if transfers[sha] == nil then
 231                                 module:log("error", "transfers[sha]: nil");
 232                         elseif(transfers[sha] ~= nil and transfers[sha].initiator ~= nil and transfers[sha].target ~= nil) then
 233                                 origin.send(reply);
 234                                 transfers[sha].activated = true;
 235                                 transfers[sha].target:lock_read(false);
 236                                 transfers[sha].initiator:lock_read(false);
 237                         else
 238                                 module:log("debug", "Both parties were not yet connected");
 239                                 local message = "Neither party is connected to the proxy";
 240                                 if transfers[sha].initiator then
 241                                         message = "The recipient is not connected to the proxy";
 242                                 elseif transfers[sha].target then
 243                                         message = "The sender (you) is not connected to the proxy";
 244                                 end
 245                                 origin.send(st.error_reply(stanza, "cancel", "not-allowed", message));
 246                         end
 247                         return true;
 248                 else
 249                         module:log("error", "activation failed: sid: %s, initiator: %s, target: %s", tostring(sid), tostring(from), tostring(to));
 250                 end
 251         end
 252 end
 253 module:hook("iq/host", handle_to_domain);
 254
 255 if not connlisteners.register(module.host .. ':proxy65', connlistener) then
 256         module:log("error", "mod_proxy65: Could not establish a connection listener. Check your configuration please.");
 257         module:log("error", "Possibly two proxy65 components are configured to share the same port.");
 258 end
 259
 260 connlisteners.start(module.host .. ':proxy65');