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