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 sessions = module:shared("sessions");
  29
  30 function module.add_host(module)
  31         if module:get_host_type() ~= "component" then
  32                 error("Don't load mod_component manually, it should be for a component, please see http://prosody.im/doc/components", 0);
  33         end
  34
  35         local env = module.environment;
  36         env.connected = false;
  37
  38         local send;
  39
  40         local function on_destroy(session, err)
  41                 env.connected = false;
  42                 send = nil;
  43                 session.on_destroy = nil;
  44         end
  45
  46         -- Handle authentication attempts by component
  47         local function handle_component_auth(event)
  48                 local session, stanza = event.origin, event.stanza;
  49
  50                 if session.type ~= "component_unauthed" then return; end
  51
  52                 if (not session.host) or #stanza.tags > 0 then
  53                         (session.log or log)("warn", "Invalid component handshake for host: %s", session.host);
  54                         session:close("not-authorized");
  55                         return true;
  56                 end
  57
  58                 local secret = module:get_option("component_secret");
  59                 if not secret then
  60                         (session.log or log)("warn", "Component attempted to identify as %s, but component_secret is not set", session.host);
  61                         session:close("not-authorized");
  62                         return true;
  63                 end
  64
  65                 local supplied_token = t_concat(stanza);
  66                 local calculated_token = sha1(session.streamid..secret, true);
  67                 if supplied_token:lower() ~= calculated_token:lower() then
  68                         module:log("info", "Component authentication failed for %s", session.host);
  69                         session:close{ condition = "not-authorized", text = "Given token does not match calculated token" };
  70                         return true;
  71                 end
  72
  73                 if env.connected then
  74                         module:log("error", "Second component attempted to connect, denying connection");
  75                         session:close{ condition = "conflict", text = "Component already connected" };
  76                         return true;
  77                 end
  78
  79                 env.connected = true;
  80                 send = session.send;
  81                 session.on_destroy = on_destroy;
  82                 session.component_validate_from = module:get_option_boolean("validate_from_addresses", true);
  83                 session.type = "component";
  84                 module:log("info", "External component successfully authenticated");
  85                 session.send(st.stanza("handshake"));
  86
  87                 return true;
  88         end
  89         module:hook("stanza/jabber:component:accept:handshake", handle_component_auth);
  90
  91         -- Handle stanzas addressed to this component
  92         local function handle_stanza(event)
  93                 local stanza = event.stanza;
  94                 if send then
  95                         stanza.attr.xmlns = nil;
  96                         send(stanza);
  97                 else
  98                         if stanza.name == "iq" and stanza.attr.type == "get" and stanza.attr.to == module.host then
  99                                 local query = stanza.tags[1];
 100                                 local node = query.attr.node;
 101                                 if query.name == "query" and query.attr.xmlns == "http://jabber.org/protocol/disco#info" and (not node or node == "") then
 102                                         local name = module:get_option_string("name");
 103                                         if name then
 104                                                 event.origin.send(st.reply(stanza):tag("query", { xmlns = "http://jabber.org/protocol/disco#info" })
 105                                                         :tag("identity", { category = "component", type = "generic", name = module:get_option_string("name", "Prosody") }))
 106                                                 return true;
 107                                         end
 108                                 end
 109                         end
 110                         module:log("warn", "Component not connected, bouncing error for: %s", stanza:top_tag());
 111                         if stanza.attr.type ~= "error" and stanza.attr.type ~= "result" then
 112                                 event.origin.send(st.error_reply(stanza, "wait", "service-unavailable", "Component unavailable"));
 113                         end
 114                 end
 115                 return true;
 116         end
 117
 118         module:hook("iq/bare", handle_stanza, -1);
 119         module:hook("message/bare", handle_stanza, -1);
 120         module:hook("presence/bare", handle_stanza, -1);
 121         module:hook("iq/full", handle_stanza, -1);
 122         module:hook("message/full", handle_stanza, -1);
 123         module:hook("presence/full", handle_stanza, -1);
 124         module:hook("iq/host", handle_stanza, -1);
 125         module:hook("message/host", handle_stanza, -1);
 126         module:hook("presence/host", handle_stanza, -1);
 127 end
 128
 129 --- Network and stream part ---
 130
 131 local xmlns_component = 'jabber:component:accept';
 132
 133 local listener = {};
 134
 135 --- Callbacks/data for xmppstream to handle streams for us ---
 136
 137 local stream_callbacks = { default_ns = xmlns_component };
 138
 139 local xmlns_xmpp_streams = "urn:ietf:params:xml:ns:xmpp-streams";
 140
 141 function stream_callbacks.error(session, error, data, data2)
 142         if session.destroyed then return; end
 143         module:log("warn", "Error processing component stream: %s", tostring(error));
 144         if error == "no-stream" then
 145                 session:close("invalid-namespace");
 146         elseif error == "parse-error" then
 147                 session.log("warn", "External component %s XML parse error: %s", tostring(session.host), tostring(data));
 148                 session:close("not-well-formed");
 149         elseif error == "stream-error" then
 150                 local condition, text = "undefined-condition";
 151                 for child in data:children() do
 152                         if child.attr.xmlns == xmlns_xmpp_streams then
 153                                 if child.name ~= "text" then
 154                                         condition = child.name;
 155                                 else
 156                                         text = child:get_text();
 157                                 end
 158                                 if condition ~= "undefined-condition" and text then
 159                                         break;
 160                                 end
 161                         end
 162                 end
 163                 text = condition .. (text and (" ("..text..")") or "");
 164                 session.log("info", "Session closed by remote with error: %s", text);
 165                 session:close(nil, text);
 166         end
 167 end
 168
 169 function stream_callbacks.streamopened(session, attr)
 170         if not hosts[attr.to] or not hosts[attr.to].modules.component then
 171                 session:close{ condition = "host-unknown", text = tostring(attr.to).." does not match any configured external components" };
 172                 return;
 173         end
 174         session.host = attr.to;
 175         session.streamid = uuid_gen();
 176         session.notopen = nil;
 177         -- Return stream header
 178         session.send("<?xml version='1.0'?>");
 179         session.send(st.stanza("stream:stream", { xmlns=xmlns_component,
 180                         ["xmlns:stream"]='http://etherx.jabber.org/streams', id=session.streamid, from=session.host }):top_tag());
 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         session.log("info", "Incoming Jabber component connection");
 274
 275         local stream = new_xmpp_stream(session, stream_callbacks);
 276         session.stream = stream;
 277
 278         session.notopen = true;
 279
 280         function session.reset_stream()
 281                 session.notopen = true;
 282                 session.stream:reset();
 283         end
 284
 285         function session.data(conn, data)
 286                 local ok, err = stream:feed(data);
 287                 if ok then return; end
 288                 module:log("debug", "Received invalid XML (%s) %d bytes: %s", tostring(err), #data, data:sub(1, 300):gsub("[\r\n]+", " "):gsub("[%z\1-\31]", "_"));
 289                 session:close("not-well-formed");
 290         end
 291
 292         session.dispatch_stanza = stream_callbacks.handlestanza;
 293
 294         sessions[conn] = session;
 295 end
 296 function listener.onincoming(conn, data)
 297         local session = sessions[conn];
 298         session.data(conn, data);
 299 end
 300 function listener.ondisconnect(conn, err)
 301         local session = sessions[conn];
 302         if session then
 303                 (session.log or log)("info", "component disconnected: %s (%s)", tostring(session.host), tostring(err));
 304                 if session.on_destroy then session:on_destroy(err); end
 305                 sessions[conn] = nil;
 306                 for k in pairs(session) do
 307                         if k ~= "log" and k ~= "close" then
 308                                 session[k] = nil;
 309                         end
 310                 end
 311                 session.destroyed = true;
 312                 session = nil;
 313         end
 314 end
 315
 316 module:provides("net", {
 317         name = "component";
 318         private = true;
 319         listener = listener;
 320         default_port = 5347;
 321         multiplex = {
 322                 pattern = "^<.*:stream.*%sxmlns%s*=%s*(['\"])jabber:component:accept%1.*>";
 323         };
 324 });