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