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