plugins/mod_component.lua

   1 -- Prosody IM
   2 -- Copyright (C) 2008-2010 Matthew Wild
   3 -- Copyright (C) 2008-2010 Waqas Hussain
   4 --
   5 -- This project is MIT/X11 licensed. Please see the
   6 -- COPYING file in the source package for more information.
   7 --
   8
   9 module:set_global();
  10
  11 local t_concat = table.concat;
  12 local xpcall, tostring, type = xpcall, tostring, type;
  13 local traceback = debug.traceback;
  14
  15 local logger = require "util.logger";
  16 local sha1 = require "util.hashes".sha1;
  17 local st = require "util.stanza";
  18
  19 local jid_split = require "util.jid".split;
  20 local new_xmpp_stream = require "util.xmppstream".new;
  21 local uuid_gen = require "util.uuid".generate;
  22
  23 local core_process_stanza = prosody.core_process_stanza;
  24 local hosts = prosody.hosts;
  25
  26 local log = module._log;
  27
  28 local opt_keepalives = module:get_option_boolean("component_tcp_keepalives", module:get_option_boolean("tcp_keepalives", true));
  29
  30 local sessions = module:shared("sessions");
  31
  32 function module.add_host(module)
  33         if module:get_host_type() ~= "component" then
  34                 error("Don't load mod_component manually, it should be for a component, please see http://prosody.im/doc/components", 0);
  35         end
  36
  37         local env = module.environment;
  38         env.connected = false;
  39
  40         local send;
  41
  42         local function on_destroy(session, err)
  43                 env.connected = false;
  44                 send = nil;
  45                 session.on_destroy = nil;
  46         end
  47
  48         -- Handle authentication attempts by component
  49         local function handle_component_auth(event)
  50                 local session, stanza = event.origin, event.stanza;
  51
  52                 if session.type ~= "component_unauthed" then return; end
  53
  54                 if (not session.host) or #stanza.tags > 0 then
  55                         (session.log or log)("warn", "Invalid component handshake for host: %s", session.host);
  56                         session:close("not-authorized");
  57                         return true;
  58                 end
  59
  60                 local secret = module:get_option("component_secret");
  61                 if not secret then
  62                         (session.log or log)("warn", "Component attempted to identify as %s, but component_secret is not set", session.host);
  63                         session:close("not-authorized");
  64                         return true;
  65                 end
  66
  67                 local supplied_token = t_concat(stanza);
  68                 local calculated_token = sha1(session.streamid..secret, true);
  69                 if supplied_token:lower() ~= calculated_token:lower() then
  70                         module:log("info", "Component authentication failed for %s", session.host);
  71                         session:close{ condition = "not-authorized", text = "Given token does not match calculated token" };
  72                         return true;
  73                 end
  74
  75                 if env.connected then
  76                         module:log("error", "Second component attempted to connect, denying connection");
  77                         session:close{ condition = "conflict", text = "Component already connected" };
  78                         return true;
  79                 end
  80
  81                 env.connected = true;
  82                 send = session.send;
  83                 session.on_destroy = on_destroy;
  84                 session.component_validate_from = module:get_option_boolean("validate_from_addresses", true);
  85                 session.type = "component";
  86                 module:log("info", "External component successfully authenticated");
  87                 session.send(st.stanza("handshake"));
  88
  89                 return true;
  90         end
  91         module:hook("stanza/jabber:component:accept:handshake", handle_component_auth, -1);
  92
  93         -- Handle stanzas addressed to this component
  94         local function handle_stanza(event)
  95                 local stanza = event.stanza;
  96                 if send then
  97                         stanza.attr.xmlns = nil;
  98                         send(stanza);
  99                 else
 100                         if stanza.name == "iq" and stanza.attr.type == "get" and stanza.attr.to == module.host then
 101                                 local query = stanza.tags[1];
 102                                 local node = query.attr.node;
 103                                 if query.name == "query" and query.attr.xmlns == "http://jabber.org/protocol/disco#info" and (not node or node == "") then
 104                                         local name = module:get_option_string("name");
 105                                         if name then
 106                                                 event.origin.send(st.reply(stanza):tag("query", { xmlns = "http://jabber.org/protocol/disco#info" })
 107                                                         :tag("identity", { category = "component", type = "generic", name = module:get_option_string("name", "Prosody") }))
 108                                                 return true;
 109                                         end
 110                                 end
 111                         end
 112                         module:log("warn", "Component not connected, bouncing error for: %s", stanza:top_tag());
 113                         if stanza.attr.type ~= "error" and stanza.attr.type ~= "result" then
 114                                 event.origin.send(st.error_reply(stanza, "wait", "service-unavailable", "Component unavailable"));
 115                         end
 116                 end
 117                 return true;
 118         end
 119
 120         module:hook("iq/bare", handle_stanza, -1);
 121         module:hook("message/bare", handle_stanza, -1);
 122         module:hook("presence/bare", handle_stanza, -1);
 123         module:hook("iq/full", handle_stanza, -1);
 124         module:hook("message/full", handle_stanza, -1);
 125         module:hook("presence/full", handle_stanza, -1);
 126         module:hook("iq/host", handle_stanza, -1);
 127         module:hook("message/host", handle_stanza, -1);
 128         module:hook("presence/host", handle_stanza, -1);
 129 end
 130
 131 --- Network and stream part ---
 132
 133 local xmlns_component = 'jabber:component:accept';
 134
 135 local listener = {};
 136
 137 --- Callbacks/data for xmppstream to handle streams for us ---
 138
 139 local stream_callbacks = { default_ns = xmlns_component };
 140
 141 local xmlns_xmpp_streams = "urn:ietf:params:xml:ns:xmpp-streams";
 142
 143 function stream_callbacks.error(session, error, data, data2)
 144         if session.destroyed then return; end
 145         module:log("warn", "Error processing component stream: %s", tostring(error));
 146         if error == "no-stream" then
 147                 session:close("invalid-namespace");
 148         elseif error == "parse-error" then
 149                 session.log("warn", "External component %s XML parse error: %s", tostring(session.host), tostring(data));
 150                 session:close("not-well-formed");
 151         elseif error == "stream-error" then
 152                 local condition, text = "undefined-condition";
 153                 for child in data:children() do
 154                         if child.attr.xmlns == xmlns_xmpp_streams then
 155                                 if child.name ~= "text" then
 156                                         condition = child.name;
 157                                 else
 158                                         text = child:get_text();
 159                                 end
 160                                 if condition ~= "undefined-condition" and text then
 161                                         break;
 162                                 end
 163                         end
 164                 end
 165                 text = condition .. (text and (" ("..text..")") or "");
 166                 session.log("info", "Session closed by remote with error: %s", text);
 167                 session:close(nil, text);
 168         end
 169 end
 170
 171 function stream_callbacks.streamopened(session, attr)
 172         if not hosts[attr.to] or not hosts[attr.to].modules.component then
 173                 session:close{ condition = "host-unknown", text = tostring(attr.to).." does not match any configured external components" };
 174                 return;
 175         end
 176         session.host = attr.to;
 177         session.streamid = uuid_gen();
 178         session.notopen = nil;
 179         -- Return stream header
 180         session:open_stream();
 181 end
 182
 183 function stream_callbacks.streamclosed(session)
 184         session.log("debug", "Received </stream:stream>");
 185         session:close();
 186 end
 187
 188 local function handleerr(err) log("error", "Traceback[component]: %s", traceback(tostring(err), 2)); end
 189 function stream_callbacks.handlestanza(session, stanza)
 190         -- Namespaces are icky.
 191         if not stanza.attr.xmlns and stanza.name == "handshake" then
 192                 stanza.attr.xmlns = xmlns_component;
 193         end
 194         if not stanza.attr.xmlns or stanza.attr.xmlns == "jabber:client" then
 195                 local from = stanza.attr.from;
 196                 if from then
 197                         if session.component_validate_from then
 198                                 local _, domain = jid_split(stanza.attr.from);
 199                                 if domain ~= session.host then
 200                                         -- Return error
 201                                         session.log("warn", "Component sent stanza with missing or invalid 'from' address");
 202                                         session:close{
 203                                                 condition = "invalid-from";
 204                                                 text = "Component tried to send from address <"..tostring(from)
 205                                                            .."> which is not in domain <"..tostring(session.host)..">";
 206                                         };
 207                                         return;
 208                                 end
 209                         end
 210                 else
 211                         stanza.attr.from = session.host; -- COMPAT: Strictly we shouldn't allow this
 212                 end
 213                 if not stanza.attr.to then
 214                         session.log("warn", "Rejecting stanza with no 'to' address");
 215                         session.send(st.error_reply(stanza, "modify", "bad-request", "Components MUST specify a 'to' address on stanzas"));
 216                         return;
 217                 end
 218         end
 219
 220         if stanza then
 221                 return xpcall(function () return core_process_stanza(session, stanza) end, handleerr);
 222         end
 223 end
 224
 225 --- Closing a component connection
 226 local stream_xmlns_attr = {xmlns='urn:ietf:params:xml:ns:xmpp-streams'};
 227 local default_stream_attr = { ["xmlns:stream"] = "http://etherx.jabber.org/streams", xmlns = stream_callbacks.default_ns, version = "1.0", id = "" };
 228 local function session_close(session, reason)
 229         if session.destroyed then return; end
 230         if session.conn then
 231                 if session.notopen then
 232                         session.send("<?xml version='1.0'?>");
 233                         session.send(st.stanza("stream:stream", default_stream_attr):top_tag());
 234                 end
 235                 if reason then
 236                         if type(reason) == "string" then -- assume stream error
 237                                 module:log("info", "Disconnecting component, <stream:error> is: %s", reason);
 238                                 session.send(st.stanza("stream:error"):tag(reason, {xmlns = 'urn:ietf:params:xml:ns:xmpp-streams' }));
 239                         elseif type(reason) == "table" then
 240                                 if reason.condition then
 241                                         local stanza = st.stanza("stream:error"):tag(reason.condition, stream_xmlns_attr):up();
 242                                         if reason.text then
 243                                                 stanza:tag("text", stream_xmlns_attr):text(reason.text):up();
 244                                         end
 245                                         if reason.extra then
 246                                                 stanza:add_child(reason.extra);
 247                                         end
 248                                         module:log("info", "Disconnecting component, <stream:error> is: %s", tostring(stanza));
 249                                         session.send(stanza);
 250                                 elseif reason.name then -- a stanza
 251                                         module:log("info", "Disconnecting component, <stream:error> is: %s", tostring(reason));
 252                                         session.send(reason);
 253                                 end
 254                         end
 255                 end
 256                 session.send("</stream:stream>");
 257                 session.conn:close();
 258                 listener.ondisconnect(session.conn, "stream error");
 259         end
 260 end
 261
 262 --- Component connlistener
 263
 264 function listener.onconnect(conn)
 265         local _send = conn.write;
 266         local session = { type = "component_unauthed", conn = conn, send = function (data) return _send(conn, tostring(data)); end };
 267
 268         -- Logging functions --
 269         local conn_name = "jcp"..tostring(session):match("[a-f0-9]+$");
 270         session.log = logger.init(conn_name);
 271         session.close = session_close;
 272
 273         if opt_keepalives then
 274                 conn:setoption("keepalive", opt_keepalives);
 275         end
 276
 277         session.log("info", "Incoming Jabber component connection");
 278
 279         local stream = new_xmpp_stream(session, stream_callbacks);
 280         session.stream = stream;
 281
 282         session.notopen = true;
 283
 284         function session.reset_stream()
 285                 session.notopen = true;
 286                 session.stream:reset();
 287         end
 288
 289         function session.data(conn, data)
 290                 local ok, err = stream:feed(data);
 291                 if ok then return; end
 292                 module:log("debug", "Received invalid XML (%s) %d bytes: %s", tostring(err), #data, data:sub(1, 300):gsub("[\r\n]+", " "):gsub("[%z\1-\31]", "_"));
 293                 session:close("not-well-formed");
 294         end
 295
 296         session.dispatch_stanza = stream_callbacks.handlestanza;
 297
 298         sessions[conn] = session;
 299 end
 300 function listener.onincoming(conn, data)
 301         local session = sessions[conn];
 302         session.data(conn, data);
 303 end
 304 function listener.ondisconnect(conn, err)
 305         local session = sessions[conn];
 306         if session then
 307                 (session.log or log)("info", "component disconnected: %s (%s)", tostring(session.host), tostring(err));
 308                 if session.on_destroy then session:on_destroy(err); end
 309                 sessions[conn] = nil;
 310                 for k in pairs(session) do
 311                         if k ~= "log" and k ~= "close" then
 312                                 session[k] = nil;
 313                         end
 314                 end
 315                 session.destroyed = true;
 316                 session = nil;
 317         end
 318 end
 319
 320 module:provides("net", {
 321         name = "component";
 322         private = true;
 323         listener = listener;
 324         default_port = 5347;
 325         multiplex = {
 326                 pattern = "^<.*:stream.*%sxmlns%s*=%s*(['\"])jabber:component:accept%1.*>";
 327         };
 328 });