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 tostring, type = tostring, type;
  13 local xpcall = require "util.xpcall".xpcall;
  14 local traceback = debug.traceback;
  15
  16 local logger = require "util.logger";
  17 local sha1 = require "util.hashes".sha1;
  18 local st = require "util.stanza";
  19
  20 local jid_split = require "util.jid".split;
  21 local new_xmpp_stream = require "util.xmppstream".new;
  22 local uuid_gen = require "util.uuid".generate;
  23
  24 local core_process_stanza = prosody.core_process_stanza;
  25 local hosts = prosody.hosts;
  26
  27 local log = module._log;
  28
  29 local opt_keepalives = module:get_option_boolean("component_tcp_keepalives", module:get_option_boolean("tcp_keepalives", true));
  30
  31 local sessions = module:shared("sessions");
  32
  33 local function keepalive(event)
  34         local session = event.session;
  35         if not session.notopen then
  36                 return event.session.send(' ');
  37         end
  38 end
  39
  40 function module.add_host(module)
  41         if module:get_host_type() ~= "component" then
  42                 error("Don't load mod_component manually, it should be for a component, please see https://prosody.im/doc/components", 0);
  43         end
  44
  45         local env = module.environment;
  46         env.connected = false;
  47         env.session = false;
  48
  49         local send;
  50
  51         local function on_destroy(session, err) --luacheck: ignore 212/err
  52                 module:set_status("warn", err and ("Disconnected: "..err) or "Disconnected");
  53                 env.connected = false;
  54                 env.session = false;
  55                 send = nil;
  56                 session.on_destroy = nil;
  57         end
  58
  59         -- Handle authentication attempts by component
  60         local function handle_component_auth(event)
  61                 local session, stanza = event.origin, event.stanza;
  62
  63                 if session.type ~= "component_unauthed" then return; end
  64
  65                 if (not session.host) or #stanza.tags > 0 then
  66                         (session.log or log)("warn", "Invalid component handshake for host: %s", session.host);
  67                         session:close("not-authorized");
  68                         return true;
  69                 end
  70
  71                 local secret = module:get_option_string("component_secret");
  72                 if not secret then
  73                         (session.log or log)("warn", "Component attempted to identify as %s, but component_secret is not set", session.host);
  74                         session:close("not-authorized");
  75                         return true;
  76                 end
  77
  78                 local supplied_token = t_concat(stanza);
  79                 local calculated_token = sha1(session.streamid..secret, true);
  80                 if supplied_token:lower() ~= calculated_token:lower() then
  81                         module:log("info", "Component authentication failed for %s", session.host);
  82                         session:close{ condition = "not-authorized", text = "Given token does not match calculated token" };
  83                         return true;
  84                 end
  85
  86                 if env.connected then
  87                         local policy = module:get_option_string("component_conflict_resolve", "kick_new");
  88                         if policy == "kick_old" then
  89                                 env.session:close{ condition = "conflict", text = "Replaced by a new connection" };
  90                         else -- kick_new
  91                                 module:log("error", "Second component attempted to connect, denying connection");
  92                                 session:close{ condition = "conflict", text = "Component already connected" };
  93                                 return true;
  94                         end
  95                 end
  96
  97                 env.connected = true;
  98                 env.session = session;
  99                 send = session.send;
 100                 session.on_destroy = on_destroy;
 101                 session.component_validate_from = module:get_option_boolean("validate_from_addresses", true);
 102                 session.type = "component";
 103                 module:log("info", "External component successfully authenticated");
 104                 session.send(st.stanza("handshake"));
 105                 module:fire_event("component-authenticated", { session = session });
 106                 module:set_status("info", "Connected");
 107
 108                 return true;
 109         end
 110         module:hook("stanza/jabber:component:accept:handshake", handle_component_auth, -1);
 111
 112         -- Handle stanzas addressed to this component
 113         local function handle_stanza(event)
 114                 local stanza = event.stanza;
 115                 if send then
 116                         stanza.attr.xmlns = nil;
 117                         send(stanza);
 118                 else
 119                         if stanza.name == "iq" and stanza.attr.type == "get" and stanza.attr.to == module.host then
 120                                 local query = stanza.tags[1];
 121                                 local node = query.attr.node;
 122                                 if query.name == "query" and query.attr.xmlns == "http://jabber.org/protocol/disco#info" and (not node or node == "") then
 123                                         local name = module:get_option_string("name");
 124                                         if name then
 125                                                 local reply = st.reply(stanza):tag("query", { xmlns = "http://jabber.org/protocol/disco#info" })
 126                                                         :tag("identity", { category = "component", type = "generic", name = module:get_option_string("name", "Prosody") }):up()
 127                                                         :tag("feature", { var = "http://jabber.org/protocol/disco#info" }):up();
 128                                                 event.origin.send(reply);
 129                                                 return true;
 130                                         end
 131                                 end
 132                         end
 133                         module:log("warn", "Component not connected, bouncing error for: %s", stanza:top_tag());
 134                         if stanza.attr.type ~= "error" and stanza.attr.type ~= "result" then
 135                                 event.origin.send(st.error_reply(stanza, "wait", "service-unavailable", "Component unavailable"));
 136                         end
 137                 end
 138                 return true;
 139         end
 140
 141         module:hook("iq/bare", handle_stanza, -1);
 142         module:hook("message/bare", handle_stanza, -1);
 143         module:hook("presence/bare", handle_stanza, -1);
 144         module:hook("iq/full", handle_stanza, -1);
 145         module:hook("message/full", handle_stanza, -1);
 146         module:hook("presence/full", handle_stanza, -1);
 147         module:hook("iq/host", handle_stanza, -1);
 148         module:hook("message/host", handle_stanza, -1);
 149         module:hook("presence/host", handle_stanza, -1);
 150
 151         module:hook("component-read-timeout", keepalive, -1);
 152 end
 153
 154 module:hook("component-read-timeout", keepalive, -1);
 155
 156 --- Network and stream part ---
 157
 158 local xmlns_component = 'jabber:component:accept';
 159
 160 local listener = {};
 161
 162 --- Callbacks/data for xmppstream to handle streams for us ---
 163
 164 local stream_callbacks = { default_ns = xmlns_component };
 165
 166 local xmlns_xmpp_streams = "urn:ietf:params:xml:ns:xmpp-streams";
 167
 168 function stream_callbacks.error(session, error, data)
 169         if session.destroyed then return; end
 170         module:log("warn", "Error processing component stream: %s", error);
 171         if error == "no-stream" then
 172                 session:close("invalid-namespace");
 173         elseif error == "parse-error" then
 174                 session.log("warn", "External component %s XML parse error: %s", session.host, data);
 175                 session:close("not-well-formed");
 176         elseif error == "stream-error" then
 177                 local condition, text = "undefined-condition";
 178                 for child in data:childtags(nil, xmlns_xmpp_streams) do
 179                         if child.name ~= "text" then
 180                                 condition = child.name;
 181                         else
 182                                 text = child:get_text();
 183                         end
 184                         if condition ~= "undefined-condition" and text then
 185                                 break;
 186                         end
 187                 end
 188                 text = condition .. (text and (" ("..text..")") or "");
 189                 session.log("info", "Session closed by remote with error: %s", text);
 190                 session:close(nil, text);
 191         end
 192 end
 193
 194 function stream_callbacks.streamopened(session, attr)
 195         if not hosts[attr.to] or not hosts[attr.to].modules.component then
 196                 session:close{ condition = "host-unknown", text = tostring(attr.to).." does not match any configured external components" };
 197                 return;
 198         end
 199         session.host = attr.to;
 200         session.streamid = uuid_gen();
 201         session.notopen = nil;
 202         -- Return stream header
 203         session:open_stream();
 204 end
 205
 206 function stream_callbacks.streamclosed(session)
 207         session.log("debug", "Received </stream:stream>");
 208         session:close();
 209 end
 210
 211 local function handleerr(err) log("error", "Traceback[component]: %s", traceback(err, 2)); end
 212 function stream_callbacks.handlestanza(session, stanza)
 213         -- Namespaces are icky.
 214         if not stanza.attr.xmlns and stanza.name == "handshake" then
 215                 stanza.attr.xmlns = xmlns_component;
 216         end
 217         if not stanza.attr.xmlns or stanza.attr.xmlns == "jabber:client" then
 218                 local from = stanza.attr.from;
 219                 if from then
 220                         if session.component_validate_from then
 221                                 local _, domain = jid_split(stanza.attr.from);
 222                                 if domain ~= session.host then
 223                                         -- Return error
 224                                         session.log("warn", "Component sent stanza with missing or invalid 'from' address");
 225                                         session:close{
 226                                                 condition = "invalid-from";
 227                                                 text = "Component tried to send from address <"..tostring(from)
 228                                                            .."> which is not in domain <"..tostring(session.host)..">";
 229                                         };
 230                                         return;
 231                                 end
 232                         end
 233                 else
 234                         stanza.attr.from = session.host; -- COMPAT: Strictly we shouldn't allow this
 235                 end
 236                 if not stanza.attr.to then
 237                         session.log("warn", "Rejecting stanza with no 'to' address");
 238                         session.send(st.error_reply(stanza, "modify", "bad-request", "Components MUST specify a 'to' address on stanzas"));
 239                         return;
 240                 end
 241         end
 242
 243         if stanza then
 244                 return xpcall(core_process_stanza, handleerr, session, stanza);
 245         end
 246 end
 247
 248 --- Closing a component connection
 249 local stream_xmlns_attr = {xmlns='urn:ietf:params:xml:ns:xmpp-streams'};
 250 local default_stream_attr = { ["xmlns:stream"] = "http://etherx.jabber.org/streams", xmlns = stream_callbacks.default_ns, version = "1.0", id = "" };
 251 local function session_close(session, reason)
 252         if session.destroyed then return; end
 253         if session.conn then
 254                 if session.notopen then
 255                         session.send("<?xml version='1.0'?>");
 256                         session.send(st.stanza("stream:stream", default_stream_attr):top_tag());
 257                 end
 258                 if reason then
 259                         if type(reason) == "string" then -- assume stream error
 260                                 module:log("info", "Disconnecting component, <stream:error> is: %s", reason);
 261                                 session.send(st.stanza("stream:error"):tag(reason, {xmlns = 'urn:ietf:params:xml:ns:xmpp-streams' }));
 262                         elseif type(reason) == "table" then
 263                                 if reason.condition then
 264                                         local stanza = st.stanza("stream:error"):tag(reason.condition, stream_xmlns_attr):up();
 265                                         if reason.text then
 266                                                 stanza:tag("text", stream_xmlns_attr):text(reason.text):up();
 267                                         end
 268                                         if reason.extra then
 269                                                 stanza:add_child(reason.extra);
 270                                         end
 271                                         module:log("info", "Disconnecting component, <stream:error> is: %s", stanza);
 272                                         session.send(stanza);
 273                                 elseif reason.name then -- a stanza
 274                                         module:log("info", "Disconnecting component, <stream:error> is: %s", reason);
 275                                         session.send(reason);
 276                                 end
 277                         end
 278                 end
 279                 session.send("</stream:stream>");
 280                 session.conn:close();
 281                 listener.ondisconnect(session.conn, "stream error");
 282         end
 283 end
 284
 285 --- Component connlistener
 286
 287 function listener.onconnect(conn)
 288         local _send = conn.write;
 289         local session = { type = "component_unauthed", conn = conn, send = function (data) return _send(conn, tostring(data)); end };
 290
 291         -- Logging functions --
 292         local conn_name = "jcp"..tostring(session):match("[a-f0-9]+$");
 293         session.log = logger.init(conn_name);
 294         session.close = session_close;
 295
 296         if opt_keepalives then
 297                 conn:setoption("keepalive", opt_keepalives);
 298         end
 299
 300         session.log("info", "Incoming Jabber component connection");
 301
 302         local stream = new_xmpp_stream(session, stream_callbacks);
 303         session.stream = stream;
 304
 305         session.notopen = true;
 306
 307         function session.reset_stream()
 308                 session.notopen = true;
 309                 session.stream:reset();
 310         end
 311
 312         function session.data(_, data)
 313                 local ok, err = stream:feed(data);
 314                 if ok then return; end
 315                 log("debug", "Received invalid XML (%s) %d bytes: %q", err, #data, data:sub(1, 300));
 316                 session:close("not-well-formed");
 317         end
 318
 319         session.dispatch_stanza = stream_callbacks.handlestanza;
 320
 321         sessions[conn] = session;
 322 end
 323 function listener.onincoming(conn, data)
 324         local session = sessions[conn];
 325         session.data(conn, data);
 326 end
 327 function listener.ondisconnect(conn, err)
 328         local session = sessions[conn];
 329         if session then
 330                 (session.log or log)("info", "component disconnected: %s (%s)", session.host, err);
 331                 if session.host then
 332                         module:context(session.host):fire_event("component-disconnected", { session = session, reason = err });
 333                 end
 334                 if session.on_destroy then session:on_destroy(err); end
 335                 sessions[conn] = nil;
 336                 for k in pairs(session) do
 337                         if k ~= "log" and k ~= "close" then
 338                                 session[k] = nil;
 339                         end
 340                 end
 341                 session.destroyed = true;
 342         end
 343 end
 344
 345 function listener.ondetach(conn)
 346         sessions[conn] = nil;
 347 end
 348
 349 function listener.onreadtimeout(conn)
 350         local session = sessions[conn];
 351         if session then
 352                 return (hosts[session.host] or prosody).events.fire_event("component-read-timeout", { session = session });
 353         end
 354 end
 355
 356 module:provides("net", {
 357         name = "component";
 358         private = true;
 359         listener = listener;
 360         default_port = 5347;
 361         multiplex = {
 362                 pattern = "^<.*:stream.*%sxmlns%s*=%s*(['\"])jabber:component:accept%1.*>";
 363         };
 364 });