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 = require "util.jid".split, require "util.jid".join;
  18 local st = require "util.stanza";
  19 local componentmanager = require "core.componentmanager";
  20 local config_get = require "core.configmanager".get;
  21 local connlisteners = require "net.connlisteners";
  22 local sha1 = require "util.hashes".sha1;
  23 local server = require "net.server";
  24
  25 local host, name = module:get_host(), "SOCKS5 Bytestreams Service";
  26 local sessions, transfers, component, replies_cache = {}, {}, nil, {};
  27
  28 local proxy_port = config_get(host, "core", "proxy65_port") or 5000;
  29 local proxy_interface = config_get(host, "core", "proxy65_interface") or "*";
  30 local proxy_address = config_get(host, "core", "proxy65_address") or (proxy_interface ~= "*" and proxy_interface) or host;
  31 local proxy_acl = config_get(host, "core", "proxy65_acl");
  32 local max_buffer_size = 4096;
  33
  34 local connlistener = { default_port = proxy_port, default_interface = proxy_interface, default_mode = "*a" };
  35
  36 function connlistener.onincoming(conn, data)
  37         local session = sessions[conn] or {};
  38
  39         if session.setup == nil and data ~= nil and data:sub(1):byte() == 0x05 and data:len() > 2 then
  40                 local nmethods = data:sub(2):byte();
  41                 local methods = data:sub(3);
  42                 local supported = false;
  43                 for i=1, nmethods, 1 do
  44                         if(methods:sub(i):byte() == 0x00) then -- 0x00 == method: NO AUTH
  45                                 supported = true;
  46                                 break;
  47                         end
  48                 end
  49                 if(supported) then
  50                         module:log("debug", "new session found ... ")
  51                         session.setup = true;
  52                         sessions[conn] = session;
  53                         conn:write(string.char(5, 0));
  54                 end
  55                 return;
  56         end
  57         if session.setup then
  58                 if session.sha ~= nil and transfers[session.sha] ~= nil then
  59                         local sha = session.sha;
  60                         if transfers[sha].activated == true and transfers[sha].target ~= nil then
  61                                 if  transfers[sha].initiator == conn then
  62                                         transfers[sha].target:write(data);
  63                                 else
  64                                         transfers[sha].initiator:write(data);
  65                                 end
  66                                 return;
  67                         end
  68                 end
  69                 if data ~= nil and data:len() == 0x2F and  -- 40 == length of SHA1 HASH, and 7 other bytes => 47 => 0x2F
  70                         data:sub(1):byte() == 0x05 and -- SOCKS5 has 5 in first byte
  71                         data:sub(2):byte() == 0x01 and -- CMD must be 1
  72                         data:sub(3):byte() == 0x00 and -- RSV must be 0
  73                         data:sub(4):byte() == 0x03 and -- ATYP must be 3
  74                         data:sub(5):byte() == 40 and -- SHA1 HASH length must be 40 (0x28)
  75                         data:sub(-2):byte() == 0x00 and -- PORT must be 0, size 2 byte
  76                         data:sub(-1):byte() == 0x00
  77                 then
  78                         local sha = data:sub(6, 45); -- second param is not count! it's the ending index (included!)
  79                         if transfers[sha] == nil then
  80                                 transfers[sha] = {};
  81                                 transfers[sha].activated = false;
  82                                 transfers[sha].target = conn;
  83                                 session.sha = sha;
  84                                 module:log("debug", "target connected ... ");
  85                         elseif transfers[sha].target ~= nil then
  86                                 transfers[sha].initiator = conn;
  87                                 session.sha = sha;
  88                                 module:log("debug", "initiator connected ... ");
  89                                 server.link(conn, transfers[sha].target, max_buffer_size);
  90                                 server.link(transfers[sha].target, conn, max_buffer_size);
  91                         end
  92                         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)
  93                         conn:lock_read(true)
  94                 else
  95                         module:log("warn", "Neither data transfer nor initial connect of a participator of a transfer.")
  96                         conn:close();
  97                 end
  98         else
  99                 if data ~= nil then
 100                         module:log("warn", "unknown connection with no authentication data -> closing it");
 101                         conn:close();
 102                 end
 103         end
 104 end
 105
 106 function connlistener.ondisconnect(conn, err)
 107         local session = sessions[conn];
 108         if session then
 109                 if session.sha and transfers[session.sha] then
 110                         local initiator, target = transfers[session.sha].initiator, transfers[session.sha].target;
 111                         if initiator == conn and target ~= nil then
 112                                 target:close();
 113                         elseif target == conn and initiator ~= nil then
 114                                 initiator:close();
 115                         end
 116                         transfers[session.sha] = nil;
 117                 end
 118                 -- Clean up any session-related stuff here
 119                 sessions[conn] = nil;
 120         end
 121 end
 122
 123 local function get_disco_info(stanza)
 124         local reply = replies_cache.disco_info;
 125         if reply == nil then
 126                 reply = st.iq({type='result', from=host}):query("http://jabber.org/protocol/disco#info")
 127                         :tag("identity", {category='proxy', type='bytestreams', name=name}):up()
 128                         :tag("feature", {var="http://jabber.org/protocol/bytestreams"});
 129                 replies_cache.disco_info = reply;
 130         end
 131
 132         reply.attr.id = stanza.attr.id;
 133         reply.attr.to = stanza.attr.from;
 134         return reply;
 135 end
 136
 137 local function get_disco_items(stanza)
 138         local reply = replies_cache.disco_items;
 139         if reply == nil then
 140                 reply = st.iq({type='result', from=host}):query("http://jabber.org/protocol/disco#items");
 141                 replies_cache.disco_items = reply;
 142         end
 143
 144         reply.attr.id = stanza.attr.id;
 145         reply.attr.to = stanza.attr.from;
 146         return reply;
 147 end
 148
 149 local function get_stream_host(origin, stanza)
 150         local reply = replies_cache.stream_host;
 151         local err_reply = replies_cache.stream_host_err;
 152         local sid = stanza.tags[1].attr.sid;
 153         local allow = false;
 154         local jid_node, jid_host, jid_resource = jid_split(stanza.attr.from);
 155
 156         if stanza.attr.from == nil then
 157                 jid_node = origin.username;
 158                 jid_host = origin.host;
 159                 jid_resource = origin.resource;
 160         end
 161
 162         if proxy_acl and #proxy_acl > 0 then
 163                 if host ~= nil then -- at least a domain is needed.
 164                         for _, acl in ipairs(proxy_acl) do
 165                                 local acl_node, acl_host, acl_resource = jid_split(acl);
 166                                 if ((acl_node ~= nil and acl_node == jid_node) or acl_node == nil) and
 167                                    ((acl_host ~= nil and acl_host == jid_host) or acl_host == nil) and
 168                                    ((acl_resource ~= nil and acl_resource == jid_resource) or acl_resource == nil) then
 169                                         allow = true;
 170                                 end
 171                         end
 172                 end
 173         else
 174                 allow = true;
 175         end
 176         if allow == true then
 177                 if reply == nil then
 178                         reply = st.iq({type="result", from=host})
 179                                 :query("http://jabber.org/protocol/bytestreams")
 180                                 :tag("streamhost", {jid=host, host=proxy_address, port=proxy_port});
 181                         replies_cache.stream_host = reply;
 182                 end
 183         else
 184                 module:log("warn", "Denying use of proxy for %s", tostring(jid_join(jid_node, jid_host, jid_resource)));
 185                 if err_reply == nil then
 186                         err_reply = st.iq({type="error", from=host})
 187                                 :query("http://jabber.org/protocol/bytestreams")
 188                                 :tag("error", {code='403', type='auth'})
 189                                 :tag("forbidden", {xmlns='urn:ietf:params:xml:ns:xmpp-stanzas'});
 190                         replies_cache.stream_host_err = err_reply;
 191                 end
 192                 reply = err_reply;
 193         end
 194         reply.attr.id = stanza.attr.id;
 195         reply.attr.to = stanza.attr.from;
 196         reply.tags[1].attr.sid = sid;
 197         return reply;
 198 end
 199
 200 module.unload = function()
 201         componentmanager.deregister_component(host);
 202         connlisteners.deregister(module.host .. ':proxy65');
 203 end
 204
 205 local function set_activation(stanza)
 206         local from, to, sid, reply = nil;
 207         from = stanza.attr.from;
 208         if stanza.tags[1] ~= nil and tostring(stanza.tags[1].name) == "query" then
 209                 if stanza.tags[1].attr ~= nil then
 210                         sid = stanza.tags[1].attr.sid;
 211                 end
 212                 if stanza.tags[1].tags[1] ~= nil and tostring(stanza.tags[1].tags[1].name) == "activate" then
 213                         to = stanza.tags[1].tags[1][1];
 214                 end
 215         end
 216         if from ~= nil and to ~= nil and sid ~= nil then
 217                 reply = st.iq({type="result", from=host, to=from});
 218                 reply.attr.id = stanza.attr.id;
 219         end
 220         return reply, from, to, sid;
 221 end
 222
 223 function handle_to_domain(origin, stanza)
 224         local to_node, to_host, to_resource = jid_split(stanza.attr.to);
 225         if to_node == nil then
 226                 local type = stanza.attr.type;
 227                 if type == "error" or type == "result" then return; end
 228                 if stanza.name == "iq" and type == "get" then
 229                         local xmlns = stanza.tags[1].attr.xmlns
 230                         if xmlns == "http://jabber.org/protocol/disco#info" then
 231                                 origin.send(get_disco_info(stanza));
 232                                 return true;
 233                         elseif xmlns == "http://jabber.org/protocol/disco#items" then
 234                                 origin.send(get_disco_items(stanza));
 235                                 return true;
 236                         elseif xmlns == "http://jabber.org/protocol/bytestreams" then
 237                                 origin.send(get_stream_host(origin, stanza));
 238                                 return true;
 239                         else
 240                                 origin.send(st.error_reply(stanza, "cancel", "service-unavailable"));
 241                                 return true;
 242                         end
 243                 elseif stanza.name == "iq" and type == "set" then
 244                         module:log("debug", "Received activation request from %s", stanza.attr.from);
 245                         local reply, from, to, sid = set_activation(stanza);
 246                         if reply ~= nil and from ~= nil and to ~= nil and sid ~= nil then
 247                                 local sha = sha1(sid .. from .. to, true);
 248                                 if transfers[sha] == nil then
 249                                         module:log("error", "transfers[sha]: nil");
 250                                 elseif(transfers[sha] ~= nil and transfers[sha].initiator ~= nil and transfers[sha].target ~= nil) then
 251                                         origin.send(reply);
 252                                         transfers[sha].activated = true;
 253                                         transfers[sha].target:lock_read(false);
 254                                         transfers[sha].initiator:lock_read(false);
 255                                 else
 256                                         module:log("debug", "Both parties were not yet connected");
 257                                         local message = "Neither party is connected to the proxy";
 258                                         if transfers[sha].initiator then
 259                                                 message = "The recipient is not connected to the proxy";
 260                                         elseif transfers[sha].target then
 261                                                 message = "The sender (you) is not connected to the proxy";
 262                                         end
 263                                         origin.send(st.error_reply(stanza, "cancel", "not-allowed", message));
 264                                 end
 265                         else
 266                                 module:log("error", "activation failed: sid: %s, initiator: %s, target: %s", tostring(sid), tostring(from), tostring(to));
 267                         end
 268                 end
 269         end
 270         return;
 271 end
 272
 273 if not connlisteners.register(module.host .. ':proxy65', connlistener) then
 274         module:log("error", "mod_proxy65: Could not establish a connection listener. Check your configuration please.");
 275         module:log("error", "Possibly two proxy65 components are configured to share the same port.");
 276 end
 277
 278 connlisteners.start(module.host .. ':proxy65');
 279 component = componentmanager.register_component(host, handle_to_domain);