plugins/muc/muc.lib.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 local select = select;
  10 local pairs, ipairs = pairs, ipairs;
  11
  12 local datetime = require "util.datetime";
  13
  14 local dataform = require "util.dataforms";
  15
  16 local jid_split = require "util.jid".split;
  17 local jid_bare = require "util.jid".bare;
  18 local jid_prep = require "util.jid".prep;
  19 local st = require "util.stanza";
  20 local log = require "util.logger".init("mod_muc");
  21 local t_insert, t_remove = table.insert, table.remove;
  22 local setmetatable = setmetatable;
  23 local base64 = require "util.encodings".base64;
  24 local md5 = require "util.hashes".md5;
  25
  26 local muc_domain = nil; --module:get_host();
  27 local default_history_length, max_history_length = 20, math.huge;
  28
  29 ------------
  30 local presence_filters = {["http://jabber.org/protocol/muc"]=true;["http://jabber.org/protocol/muc#user"]=true};
  31 local function presence_filter(tag)
  32         if presence_filters[tag.attr.xmlns] then
  33                 return nil;
  34         end
  35         return tag;
  36 end
  37
  38 local function get_filtered_presence(stanza)
  39         return st.clone(stanza):maptags(presence_filter);
  40 end
  41 local kickable_error_conditions = {
  42         ["gone"] = true;
  43         ["internal-server-error"] = true;
  44         ["item-not-found"] = true;
  45         ["jid-malformed"] = true;
  46         ["recipient-unavailable"] = true;
  47         ["redirect"] = true;
  48         ["remote-server-not-found"] = true;
  49         ["remote-server-timeout"] = true;
  50         ["service-unavailable"] = true;
  51         ["malformed error"] = true;
  52 };
  53
  54 local function get_error_condition(stanza)
  55         local _, condition = stanza:get_error();
  56         return condition or "malformed error";
  57 end
  58
  59 local function is_kickable_error(stanza)
  60         local cond = get_error_condition(stanza);
  61         return kickable_error_conditions[cond] and cond;
  62 end
  63 -----------
  64
  65 local room_mt = {};
  66 room_mt.__index = room_mt;
  67
  68 function room_mt:__tostring()
  69         return "MUC room ("..self.jid..")";
  70 end
  71
  72 function room_mt:get_default_role(affiliation)
  73         if affiliation == "owner" or affiliation == "admin" then
  74                 return "moderator";
  75         elseif affiliation == "member" then
  76                 return "participant";
  77         elseif not affiliation then
  78                 if not self:get_members_only() then
  79                         return self:get_moderated() and "visitor" or "participant";
  80                 end
  81         end
  82 end
  83
  84 function room_mt:broadcast_presence(stanza, sid, code, nick)
  85         stanza = get_filtered_presence(stanza);
  86         local occupant = self._occupants[stanza.attr.from];
  87         stanza:tag("x", {xmlns='http://jabber.org/protocol/muc#user'})
  88                 :tag("item", {affiliation=occupant.affiliation or "none", role=occupant.role or "none", nick=nick}):up();
  89         if code then
  90                 stanza:tag("status", {code=code}):up();
  91         end
  92         self:broadcast_except_nick(stanza, stanza.attr.from);
  93         local me = self._occupants[stanza.attr.from];
  94         if me then
  95                 stanza:tag("status", {code='110'}):up();
  96                 stanza.attr.to = sid;
  97                 self:_route_stanza(stanza);
  98         end
  99 end
 100 function room_mt:broadcast_message(stanza, historic)
 101         local to = stanza.attr.to;
 102         for occupant, o_data in pairs(self._occupants) do
 103                 for jid in pairs(o_data.sessions) do
 104                         stanza.attr.to = jid;
 105                         self:_route_stanza(stanza);
 106                 end
 107         end
 108         stanza.attr.to = to;
 109         if historic then -- add to history
 110                 local history = self._data['history'];
 111                 if not history then history = {}; self._data['history'] = history; end
 112                 stanza = st.clone(stanza);
 113                 stanza.attr.to = "";
 114                 local stamp = datetime.datetime();
 115                 stanza:tag("delay", {xmlns = "urn:xmpp:delay", from = muc_domain, stamp = stamp}):up(); -- XEP-0203
 116                 stanza:tag("x", {xmlns = "jabber:x:delay", from = muc_domain, stamp = datetime.legacy()}):up(); -- XEP-0091 (deprecated)
 117                 local entry = { stanza = stanza, stamp = stamp };
 118                 t_insert(history, entry);
 119                 while #history > (self._data.history_length or default_history_length) do t_remove(history, 1) end
 120         end
 121 end
 122 function room_mt:broadcast_except_nick(stanza, nick)
 123         for rnick, occupant in pairs(self._occupants) do
 124                 if rnick ~= nick then
 125                         for jid in pairs(occupant.sessions) do
 126                                 stanza.attr.to = jid;
 127                                 self:_route_stanza(stanza);
 128                         end
 129                 end
 130         end
 131 end
 132
 133 function room_mt:send_occupant_list(to)
 134         local current_nick = self._jid_nick[to];
 135         for occupant, o_data in pairs(self._occupants) do
 136                 if occupant ~= current_nick then
 137                         local pres = get_filtered_presence(o_data.sessions[o_data.jid]);
 138                         pres.attr.to, pres.attr.from = to, occupant;
 139                         pres:tag("x", {xmlns='http://jabber.org/protocol/muc#user'})
 140                                 :tag("item", {affiliation=o_data.affiliation or "none", role=o_data.role or "none"}):up();
 141                         self:_route_stanza(pres);
 142                 end
 143         end
 144 end
 145 function room_mt:send_history(to, stanza)
 146         local history = self._data['history']; -- send discussion history
 147         if history then
 148                 local x_tag = stanza and stanza:get_child("x", "http://jabber.org/protocol/muc");
 149                 local history_tag = x_tag and x_tag:get_child("history", "http://jabber.org/protocol/muc");
 150
 151                 local maxchars = history_tag and tonumber(history_tag.attr.maxchars);
 152                 if maxchars then maxchars = math.floor(maxchars); end
 153
 154                 local maxstanzas = math.floor(history_tag and tonumber(history_tag.attr.maxstanzas) or #history);
 155                 if not history_tag then maxstanzas = 20; end
 156
 157                 local seconds = history_tag and tonumber(history_tag.attr.seconds);
 158                 if seconds then seconds = datetime.datetime(os.time() - math.floor(seconds)); end
 159
 160                 local since = history_tag and history_tag.attr.since;
 161                 if since then since = datetime.parse(since); since = since and datetime.datetime(since); end
 162                 if seconds and (not since or since < seconds) then since = seconds; end
 163
 164                 local n = 0;
 165                 local charcount = 0;
 166
 167                 for i=#history,1,-1 do
 168                         local entry = history[i];
 169                         if maxchars then
 170                                 if not entry.chars then
 171                                         entry.stanza.attr.to = "";
 172                                         entry.chars = #tostring(entry.stanza);
 173                                 end
 174                                 charcount = charcount + entry.chars + #to;
 175                                 if charcount > maxchars then break; end
 176                         end
 177                         if since and since > entry.stamp then break; end
 178                         if n + 1 > maxstanzas then break; end
 179                         n = n + 1;
 180                 end
 181                 for i=#history-n+1,#history do
 182                         local msg = history[i].stanza;
 183                         msg.attr.to = to;
 184                         self:_route_stanza(msg);
 185                 end
 186         end
 187         if self._data['subject'] then
 188                 self:_route_stanza(st.message({type='groupchat', from=self._data['subject_from'] or self.jid, to=to}):tag("subject"):text(self._data['subject']));
 189         end
 190 end
 191
 192 function room_mt:get_disco_info(stanza)
 193         local count = 0; for _ in pairs(self._occupants) do count = count + 1; end
 194         return st.reply(stanza):query("http://jabber.org/protocol/disco#info")
 195                 :tag("identity", {category="conference", type="text", name=self:get_name()}):up()
 196                 :tag("feature", {var="http://jabber.org/protocol/muc"}):up()
 197                 :tag("feature", {var=self:get_password() and "muc_passwordprotected" or "muc_unsecured"}):up()
 198                 :tag("feature", {var=self:get_moderated() and "muc_moderated" or "muc_unmoderated"}):up()
 199                 :tag("feature", {var=self:get_members_only() and "muc_membersonly" or "muc_open"}):up()
 200                 :tag("feature", {var=self:get_persistent() and "muc_persistent" or "muc_temporary"}):up()
 201                 :tag("feature", {var=self:get_hidden() and "muc_hidden" or "muc_public"}):up()
 202                 :tag("feature", {var=self._data.whois ~= "anyone" and "muc_semianonymous" or "muc_nonanonymous"}):up()
 203                 :add_child(dataform.new({
 204                         { name = "FORM_TYPE", type = "hidden", value = "http://jabber.org/protocol/muc#roominfo" },
 205                         { name = "muc#roominfo_description", label = "Description"},
 206                         { name = "muc#roominfo_occupants", label = "Number of occupants", value = tostring(count) }
 207                 }):form({["muc#roominfo_description"] = self:get_description()}, 'result'))
 208         ;
 209 end
 210 function room_mt:get_disco_items(stanza)
 211         local reply = st.reply(stanza):query("http://jabber.org/protocol/disco#items");
 212         for room_jid in pairs(self._occupants) do
 213                 reply:tag("item", {jid = room_jid, name = room_jid:match("/(.*)")}):up();
 214         end
 215         return reply;
 216 end
 217 function room_mt:set_subject(current_nick, subject)
 218         -- TODO check nick's authority
 219         if subject == "" then subject = nil; end
 220         self._data['subject'] = subject;
 221         self._data['subject_from'] = current_nick;
 222         if self.save then self:save(); end
 223         local msg = st.message({type='groupchat', from=current_nick})
 224                 :tag('subject'):text(subject):up();
 225         self:broadcast_message(msg, false);
 226         return true;
 227 end
 228
 229 local function build_unavailable_presence_from_error(stanza)
 230         local type, condition, text = stanza:get_error();
 231         local error_message = "Kicked: "..(condition and condition:gsub("%-", " ") or "presence error");
 232         if text then
 233                 error_message = error_message..": "..text;
 234         end
 235         return st.presence({type='unavailable', from=stanza.attr.from, to=stanza.attr.to})
 236                 :tag('status'):text(error_message);
 237 end
 238
 239 function room_mt:set_name(name)
 240         if name == "" or type(name) ~= "string" or name == (jid_split(self.jid)) then name = nil; end
 241         if self._data.name ~= name then
 242                 self._data.name = name;
 243                 if self.save then self:save(true); end
 244         end
 245 end
 246 function room_mt:get_name()
 247         return self._data.name or jid_split(self.jid);
 248 end
 249 function room_mt:set_description(description)
 250         if description == "" or type(description) ~= "string" then description = nil; end
 251         if self._data.description ~= description then
 252                 self._data.description = description;
 253                 if self.save then self:save(true); end
 254         end
 255 end
 256 function room_mt:get_description()
 257         return self._data.description;
 258 end
 259 function room_mt:set_password(password)
 260         if password == "" or type(password) ~= "string" then password = nil; end
 261         if self._data.password ~= password then
 262                 self._data.password = password;
 263                 if self.save then self:save(true); end
 264         end
 265 end
 266 function room_mt:get_password()
 267         return self._data.password;
 268 end
 269 function room_mt:set_moderated(moderated)
 270         moderated = moderated and true or nil;
 271         if self._data.moderated ~= moderated then
 272                 self._data.moderated = moderated;
 273                 if self.save then self:save(true); end
 274         end
 275 end
 276 function room_mt:get_moderated()
 277         return self._data.moderated;
 278 end
 279 function room_mt:set_members_only(members_only)
 280         members_only = members_only and true or nil;
 281         if self._data.members_only ~= members_only then
 282                 self._data.members_only = members_only;
 283                 if self.save then self:save(true); end
 284         end
 285 end
 286 function room_mt:get_members_only()
 287         return self._data.members_only;
 288 end
 289 function room_mt:set_persistent(persistent)
 290         persistent = persistent and true or nil;
 291         if self._data.persistent ~= persistent then
 292                 self._data.persistent = persistent;
 293                 if self.save then self:save(true); end
 294         end
 295 end
 296 function room_mt:get_persistent()
 297         return self._data.persistent;
 298 end
 299 function room_mt:set_hidden(hidden)
 300         hidden = hidden and true or nil;
 301         if self._data.hidden ~= hidden then
 302                 self._data.hidden = hidden;
 303                 if self.save then self:save(true); end
 304         end
 305 end
 306 function room_mt:get_hidden()
 307         return self._data.hidden;
 308 end
 309 function room_mt:get_public()
 310         return not self:get_hidden();
 311 end
 312 function room_mt:set_public(public)
 313         return self:set_hidden(not public);
 314 end
 315 function room_mt:set_changesubject(changesubject)
 316         changesubject = changesubject and true or nil;
 317         if self._data.changesubject ~= changesubject then
 318                 self._data.changesubject = changesubject;
 319                 if self.save then self:save(true); end
 320         end
 321 end
 322 function room_mt:get_changesubject()
 323         return self._data.changesubject;
 324 end
 325 function room_mt:get_historylength()
 326         return self._data.history_length or default_history_length;
 327 end
 328 function room_mt:set_historylength(length)
 329         length = math.min(tonumber(length) or default_history_length, max_history_length or math.huge);
 330         if length == default_history_length then
 331                 length = nil;
 332         end
 333         self._data.history_length = length;
 334 end
 335
 336
 337 local valid_whois = { moderators = true, anyone = true };
 338
 339 function room_mt:set_whois(whois)
 340         if valid_whois[whois] and self._data.whois ~= whois then
 341                 self._data.whois = whois;
 342                 if self.save then self:save(true); end
 343         end
 344 end
 345
 346 function room_mt:get_whois()
 347         return self._data.whois;
 348 end
 349
 350 local function construct_stanza_id(room, stanza)
 351         local from_jid, to_nick = stanza.attr.from, stanza.attr.to;
 352         local from_nick = room._jid_nick[from_jid];
 353         local occupant = room._occupants[to_nick];
 354         local to_jid = occupant.jid;
 355
 356         return from_nick, to_jid, base64.encode(to_jid.."\0"..stanza.attr.id.."\0"..md5(from_jid));
 357 end
 358 local function deconstruct_stanza_id(room, stanza)
 359         local from_jid_possiblybare, to_nick = stanza.attr.from, stanza.attr.to;
 360         local from_jid, id, to_jid_hash = (base64.decode(stanza.attr.id) or ""):match("^(.+)%z(.*)%z(.+)$");
 361         local from_nick = room._jid_nick[from_jid];
 362
 363         if not(from_nick) then return; end
 364         if not(from_jid_possiblybare == from_jid or from_jid_possiblybare == jid_bare(from_jid)) then return; end
 365
 366         local occupant = room._occupants[to_nick];
 367         for to_jid in pairs(occupant and occupant.sessions or {}) do
 368                 if md5(to_jid) == to_jid_hash then
 369                         return from_nick, to_jid, id;
 370                 end
 371         end
 372 end
 373
 374
 375 function room_mt:handle_to_occupant(origin, stanza) -- PM, vCards, etc
 376         local from, to = stanza.attr.from, stanza.attr.to;
 377         local room = jid_bare(to);
 378         local current_nick = self._jid_nick[from];
 379         local type = stanza.attr.type;
 380         log("debug", "room: %s, current_nick: %s, stanza: %s", room or "nil", current_nick or "nil", stanza:top_tag());
 381         if (select(2, jid_split(from)) == muc_domain) then error("Presence from the MUC itself!!!"); end
 382         if stanza.name == "presence" then
 383                 local pr = get_filtered_presence(stanza);
 384                 pr.attr.from = current_nick;
 385                 if type == "error" then -- error, kick em out!
 386                         if current_nick then
 387                                 log("debug", "kicking %s from %s", current_nick, room);
 388                                 self:handle_to_occupant(origin, build_unavailable_presence_from_error(stanza));
 389                         end
 390                 elseif type == "unavailable" then -- unavailable
 391                         if current_nick then
 392                                 log("debug", "%s leaving %s", current_nick, room);
 393                                 self._jid_nick[from] = nil;
 394                                 local occupant = self._occupants[current_nick];
 395                                 local new_jid = next(occupant.sessions);
 396                                 if new_jid == from then new_jid = next(occupant.sessions, new_jid); end
 397                                 if new_jid then
 398                                         local jid = occupant.jid;
 399                                         occupant.jid = new_jid;
 400                                         occupant.sessions[from] = nil;
 401                                         pr.attr.to = from;
 402                                         pr:tag("x", {xmlns='http://jabber.org/protocol/muc#user'})
 403                                                 :tag("item", {affiliation=occupant.affiliation or "none", role='none'}):up()
 404                                                 :tag("status", {code='110'}):up();
 405                                         self:_route_stanza(pr);
 406                                         if jid ~= new_jid then
 407                                                 pr = st.clone(occupant.sessions[new_jid])
 408                                                         :tag("x", {xmlns='http://jabber.org/protocol/muc#user'})
 409                                                         :tag("item", {affiliation=occupant.affiliation or "none", role=occupant.role or "none"});
 410                                                 pr.attr.from = current_nick;
 411                                                 self:broadcast_except_nick(pr, current_nick);
 412                                         end
 413                                 else
 414                                         occupant.role = 'none';
 415                                         self:broadcast_presence(pr, from);
 416                                         self._occupants[current_nick] = nil;
 417                                 end
 418                         end
 419                 elseif not type then -- available
 420                         if current_nick then
 421                                 --if #pr == #stanza or current_nick ~= to then -- commented because google keeps resending directed presence
 422                                         if current_nick == to then -- simple presence
 423                                                 log("debug", "%s broadcasted presence", current_nick);
 424                                                 self._occupants[current_nick].sessions[from] = pr;
 425                                                 self:broadcast_presence(pr, from);
 426                                         else -- change nick
 427                                                 local occupant = self._occupants[current_nick];
 428                                                 local is_multisession = next(occupant.sessions, next(occupant.sessions));
 429                                                 if self._occupants[to] or is_multisession then
 430                                                         log("debug", "%s couldn't change nick", current_nick);
 431                                                         local reply = st.error_reply(stanza, "cancel", "conflict"):up();
 432                                                         reply.tags[1].attr.code = "409";
 433                                                         origin.send(reply:tag("x", {xmlns = "http://jabber.org/protocol/muc"}));
 434                                                 else
 435                                                         local data = self._occupants[current_nick];
 436                                                         local to_nick = select(3, jid_split(to));
 437                                                         if to_nick then
 438                                                                 log("debug", "%s (%s) changing nick to %s", current_nick, data.jid, to);
 439                                                                 local p = st.presence({type='unavailable', from=current_nick});
 440                                                                 self:broadcast_presence(p, from, '303', to_nick);
 441                                                                 self._occupants[current_nick] = nil;
 442                                                                 self._occupants[to] = data;
 443                                                                 self._jid_nick[from] = to;
 444                                                                 pr.attr.from = to;
 445                                                                 self._occupants[to].sessions[from] = pr;
 446                                                                 self:broadcast_presence(pr, from);
 447                                                         else
 448                                                                 --TODO malformed-jid
 449                                                         end
 450                                                 end
 451                                         end
 452                                 --else -- possible rejoin
 453                                 --      log("debug", "%s had connection replaced", current_nick);
 454                                 --      self:handle_to_occupant(origin, st.presence({type='unavailable', from=from, to=to})
 455                                 --              :tag('status'):text('Replaced by new connection'):up()); -- send unavailable
 456                                 --      self:handle_to_occupant(origin, stanza); -- resend available
 457                                 --end
 458                         else -- enter room
 459                                 local new_nick = to;
 460                                 local is_merge;
 461                                 if self._occupants[to] then
 462                                         if jid_bare(from) ~= jid_bare(self._occupants[to].jid) then
 463                                                 new_nick = nil;
 464                                         end
 465                                         is_merge = true;
 466                                 end
 467                                 local password = stanza:get_child("x", "http://jabber.org/protocol/muc");
 468                                 password = password and password:get_child("password", "http://jabber.org/protocol/muc");
 469                                 password = password and password[1] ~= "" and password[1];
 470                                 if self:get_password() and self:get_password() ~= password then
 471                                         log("debug", "%s couldn't join due to invalid password: %s", from, to);
 472                                         local reply = st.error_reply(stanza, "auth", "not-authorized"):up();
 473                                         reply.tags[1].attr.code = "401";
 474                                         origin.send(reply:tag("x", {xmlns = "http://jabber.org/protocol/muc"}));
 475                                 elseif not new_nick then
 476                                         log("debug", "%s couldn't join due to nick conflict: %s", from, to);
 477                                         local reply = st.error_reply(stanza, "cancel", "conflict"):up();
 478                                         reply.tags[1].attr.code = "409";
 479                                         origin.send(reply:tag("x", {xmlns = "http://jabber.org/protocol/muc"}));
 480                                 else
 481                                         log("debug", "%s joining as %s", from, to);
 482                                         if not next(self._affiliations) then -- new room, no owners
 483                                                 self._affiliations[jid_bare(from)] = "owner";
 484                                         end
 485                                         local affiliation = self:get_affiliation(from);
 486                                         local role = self:get_default_role(affiliation)
 487                                         if role then -- new occupant
 488                                                 if not is_merge then
 489                                                         self._occupants[to] = {affiliation=affiliation, role=role, jid=from, sessions={[from]=get_filtered_presence(stanza)}};
 490                                                 else
 491                                                         self._occupants[to].sessions[from] = get_filtered_presence(stanza);
 492                                                 end
 493                                                 self._jid_nick[from] = to;
 494                                                 self:send_occupant_list(from);
 495                                                 pr.attr.from = to;
 496                                                 pr:tag("x", {xmlns='http://jabber.org/protocol/muc#user'})
 497                                                         :tag("item", {affiliation=affiliation or "none", role=role or "none"}):up();
 498                                                 if not is_merge then
 499                                                         self:broadcast_except_nick(pr, to);
 500                                                 end
 501                                                 pr:tag("status", {code='110'}):up();
 502                                                 if self._data.whois == 'anyone' then
 503                                                         pr:tag("status", {code='100'}):up();
 504                                                 end
 505                                                 pr.attr.to = from;
 506                                                 self:_route_stanza(pr);
 507                                                 self:send_history(from, stanza);
 508                                         elseif not affiliation then -- registration required for entering members-only room
 509                                                 local reply = st.error_reply(stanza, "auth", "registration-required"):up();
 510                                                 reply.tags[1].attr.code = "407";
 511                                                 origin.send(reply:tag("x", {xmlns = "http://jabber.org/protocol/muc"}));
 512                                         else -- banned
 513                                                 local reply = st.error_reply(stanza, "auth", "forbidden"):up();
 514                                                 reply.tags[1].attr.code = "403";
 515                                                 origin.send(reply:tag("x", {xmlns = "http://jabber.org/protocol/muc"}));
 516                                         end
 517                                 end
 518                         end
 519                 elseif type ~= 'result' then -- bad type
 520                         if type ~= 'visible' and type ~= 'invisible' then -- COMPAT ejabberd can broadcast or forward XEP-0018 presences
 521                                 origin.send(st.error_reply(stanza, "modify", "bad-request")); -- FIXME correct error?
 522                         end
 523                 end
 524         elseif not current_nick then -- not in room
 525                 if (type == "error" or type == "result") and stanza.name == "iq" then
 526                         local id = stanza.attr.id;
 527                         stanza.attr.from, stanza.attr.to, stanza.attr.id = deconstruct_stanza_id(self, stanza);
 528                         if stanza.attr.id then
 529                                 self:_route_stanza(stanza);
 530                         end
 531                         stanza.attr.from, stanza.attr.to, stanza.attr.id = from, to, id;
 532                 elseif type ~= "error" then
 533                         origin.send(st.error_reply(stanza, "cancel", "not-acceptable"));
 534                 end
 535         elseif stanza.name == "message" and type == "groupchat" then -- groupchat messages not allowed in PM
 536                 origin.send(st.error_reply(stanza, "modify", "bad-request"));
 537         elseif current_nick and stanza.name == "message" and type == "error" and is_kickable_error(stanza) then
 538                 log("debug", "%s kicked from %s for sending an error message", current_nick, self.jid);
 539                 self:handle_to_occupant(origin, build_unavailable_presence_from_error(stanza)); -- send unavailable
 540         else -- private stanza
 541                 local o_data = self._occupants[to];
 542                 if o_data then
 543                         log("debug", "%s sent private stanza to %s (%s)", from, to, o_data.jid);
 544                         if stanza.name == "iq" then
 545                                 local id = stanza.attr.id;
 546                                 if stanza.attr.type == "get" or stanza.attr.type == "set" then
 547                                         stanza.attr.from, stanza.attr.to, stanza.attr.id = construct_stanza_id(self, stanza);
 548                                 else
 549                                         stanza.attr.from, stanza.attr.to, stanza.attr.id = deconstruct_stanza_id(self, stanza);
 550                                 end
 551                                 if type == 'get' and stanza.tags[1].attr.xmlns == 'vcard-temp' then
 552                                         stanza.attr.to = jid_bare(stanza.attr.to);
 553                                 end
 554                                 if stanza.attr.id then
 555                                         self:_route_stanza(stanza);
 556                                 end
 557                                 stanza.attr.from, stanza.attr.to, stanza.attr.id = from, to, id;
 558                         else -- message
 559                                 stanza.attr.from = current_nick;
 560                                 for jid in pairs(o_data.sessions) do
 561                                         stanza.attr.to = jid;
 562                                         self:_route_stanza(stanza);
 563                                 end
 564                                 stanza.attr.from, stanza.attr.to = from, to;
 565                         end
 566                 elseif type ~= "error" and type ~= "result" then -- recipient not in room
 567                         origin.send(st.error_reply(stanza, "cancel", "item-not-found", "Recipient not in room"));
 568                 end
 569         end
 570 end
 571
 572 function room_mt:send_form(origin, stanza)
 573         origin.send(st.reply(stanza):query("http://jabber.org/protocol/muc#owner")
 574                 :add_child(self:get_form_layout(stanza.attr.from):form())
 575         );
 576 end
 577
 578 function room_mt:get_form_layout(actor)
 579         local form = dataform.new({
 580                 title = "Configuration for "..self.jid,
 581                 instructions = "Complete and submit this form to configure the room.",
 582                 {
 583                         name = 'FORM_TYPE',
 584                         type = 'hidden',
 585                         value = 'http://jabber.org/protocol/muc#roomconfig'
 586                 },
 587                 {
 588                         name = 'muc#roomconfig_roomname',
 589                         type = 'text-single',
 590                         label = 'Name',
 591                         value = self:get_name() or "",
 592                 },
 593                 {
 594                         name = 'muc#roomconfig_roomdesc',
 595                         type = 'text-single',
 596                         label = 'Description',
 597                         value = self:get_description() or "",
 598                 },
 599                 {
 600                         name = 'muc#roomconfig_persistentroom',
 601                         type = 'boolean',
 602                         label = 'Make Room Persistent?',
 603                         value = self:get_persistent()
 604                 },
 605                 {
 606                         name = 'muc#roomconfig_publicroom',
 607                         type = 'boolean',
 608                         label = 'Make Room Publicly Searchable?',
 609                         value = not self:get_hidden()
 610                 },
 611                 {
 612                         name = 'muc#roomconfig_changesubject',
 613                         type = 'boolean',
 614                         label = 'Allow Occupants to Change Subject?',
 615                         value = self:get_changesubject()
 616                 },
 617                 {
 618                         name = 'muc#roomconfig_whois',
 619                         type = 'list-single',
 620                         label = 'Who May Discover Real JIDs?',
 621                         value = {
 622                                 { value = 'moderators', label = 'Moderators Only', default = self._data.whois == 'moderators' },
 623                                 { value = 'anyone',     label = 'Anyone',          default = self._data.whois == 'anyone' }
 624                         }
 625                 },
 626                 {
 627                         name = 'muc#roomconfig_roomsecret',
 628                         type = 'text-private',
 629                         label = 'Password',
 630                         value = self:get_password() or "",
 631                 },
 632                 {
 633                         name = 'muc#roomconfig_moderatedroom',
 634                         type = 'boolean',
 635                         label = 'Make Room Moderated?',
 636                         value = self:get_moderated()
 637                 },
 638                 {
 639                         name = 'muc#roomconfig_membersonly',
 640                         type = 'boolean',
 641                         label = 'Make Room Members-Only?',
 642                         value = self:get_members_only()
 643                 },
 644                 {
 645                         name = 'muc#roomconfig_historylength',
 646                         type = 'text-single',
 647                         label = 'Maximum Number of History Messages Returned by Room',
 648                         value = tostring(self:get_historylength())
 649                 }
 650         });
 651         return module:fire_event("muc-config-form", { room = self, actor = actor, form = form }) or form;
 652 end
 653
 654 function room_mt:process_form(origin, stanza)
 655         local query = stanza.tags[1];
 656         local form;
 657         for _, tag in ipairs(query.tags) do if tag.name == "x" and tag.attr.xmlns == "jabber:x:data" then form = tag; break; end end
 658         if not form then origin.send(st.error_reply(stanza, "cancel", "service-unavailable")); return; end
 659         if form.attr.type == "cancel" then origin.send(st.reply(stanza)); return; end
 660         if form.attr.type ~= "submit" then origin.send(st.error_reply(stanza, "cancel", "bad-request", "Not a submitted form")); return; end
 661
 662         local fields = self:get_form_layout(stanza.attr.from):data(form);
 663         if fields.FORM_TYPE ~= "http://jabber.org/protocol/muc#roomconfig" then origin.send(st.error_reply(stanza, "cancel", "bad-request", "Form is not of type room configuration")); return; end
 664
 665
 666         local changed = {};
 667
 668         local function handle_option(name, field, allowed)
 669                 local new = fields[field];
 670                 if new == nil then return; end
 671                 if allowed and not allowed[new] then return; end
 672                 if new == self["get_"..name](self) then return; end
 673                 changed[name] = true;
 674                 self["set_"..name](self, new);
 675         end
 676
 677         local event = { room = self, fields = fields, changed = changed, stanza = stanza, origin = origin, update_option = handle_option };
 678         module:fire_event("muc-config-submitted", event);
 679
 680         handle_option("name", "muc#roomconfig_roomname");
 681         handle_option("description", "muc#roomconfig_roomdesc");
 682         handle_option("persistent", "muc#roomconfig_persistentroom");
 683         handle_option("moderated", "muc#roomconfig_moderatedroom");
 684         handle_option("members_only", "muc#roomconfig_membersonly");
 685         handle_option("public", "muc#roomconfig_publicroom");
 686         handle_option("changesubject", "muc#roomconfig_changesubject");
 687         handle_option("historylength", "muc#roomconfig_historylength");
 688         handle_option("whois", "muc#roomconfig_whois", valid_whois);
 689         handle_option("password", "muc#roomconfig_roomsecret");
 690
 691         if self.save then self:save(true); end
 692         origin.send(st.reply(stanza));
 693
 694         if next(changed) then
 695                 local msg = st.message({type='groupchat', from=self.jid})
 696                         :tag('x', {xmlns='http://jabber.org/protocol/muc#user'}):up()
 697                                 :tag('status', {code = '104'}):up();
 698                 if changed.whois then
 699                         local code = (self:get_whois() == 'moderators') and "173" or "172";
 700                         msg.tags[1]:tag('status', {code = code}):up();
 701                 end
 702                 self:broadcast_message(msg, false)
 703         end
 704 end
 705
 706 function room_mt:destroy(newjid, reason, password)
 707         local pr = st.presence({type = "unavailable"})
 708                 :tag("x", {xmlns = "http://jabber.org/protocol/muc#user"})
 709                         :tag("item", { affiliation='none', role='none' }):up()
 710                         :tag("destroy", {jid=newjid})
 711         if reason then pr:tag("reason"):text(reason):up(); end
 712         if password then pr:tag("password"):text(password):up(); end
 713         for nick, occupant in pairs(self._occupants) do
 714                 pr.attr.from = nick;
 715                 for jid in pairs(occupant.sessions) do
 716                         pr.attr.to = jid;
 717                         self:_route_stanza(pr);
 718                         self._jid_nick[jid] = nil;
 719                 end
 720                 self._occupants[nick] = nil;
 721         end
 722         self:set_persistent(false);
 723         module:fire_event("muc-room-destroyed", { room = self });
 724 end
 725
 726 function room_mt:handle_to_room(origin, stanza) -- presence changes and groupchat messages, along with disco/etc
 727         local type = stanza.attr.type;
 728         local xmlns = stanza.tags[1] and stanza.tags[1].attr.xmlns;
 729         if stanza.name == "iq" then
 730                 if xmlns == "http://jabber.org/protocol/disco#info" and type == "get" and not stanza.tags[1].attr.node then
 731                         origin.send(self:get_disco_info(stanza));
 732                 elseif xmlns == "http://jabber.org/protocol/disco#items" and type == "get" and not stanza.tags[1].attr.node then
 733                         origin.send(self:get_disco_items(stanza));
 734                 elseif xmlns == "http://jabber.org/protocol/muc#admin" then
 735                         local actor = stanza.attr.from;
 736                         local affiliation = self:get_affiliation(actor);
 737                         local current_nick = self._jid_nick[actor];
 738                         local role = current_nick and self._occupants[current_nick].role or self:get_default_role(affiliation);
 739                         local item = stanza.tags[1].tags[1];
 740                         if item and item.name == "item" then
 741                                 if type == "set" then
 742                                         local callback = function() origin.send(st.reply(stanza)); end
 743                                         if item.attr.jid then -- Validate provided JID
 744                                                 item.attr.jid = jid_prep(item.attr.jid);
 745                                                 if not item.attr.jid then
 746                                                         origin.send(st.error_reply(stanza, "modify", "jid-malformed"));
 747                                                         return;
 748                                                 end
 749                                         end
 750                                         if not item.attr.jid and item.attr.nick then -- COMPAT Workaround for Miranda sending 'nick' instead of 'jid' when changing affiliation
 751                                                 local occupant = self._occupants[self.jid.."/"..item.attr.nick];
 752                                                 if occupant then item.attr.jid = occupant.jid; end
 753                                         elseif not item.attr.nick and item.attr.jid then
 754                                                 local nick = self._jid_nick[item.attr.jid];
 755                                                 if nick then item.attr.nick = select(3, jid_split(nick)); end
 756                                         end
 757                                         local reason = item.tags[1] and item.tags[1].name == "reason" and #item.tags[1] == 1 and item.tags[1][1];
 758                                         if item.attr.affiliation and item.attr.jid and not item.attr.role then
 759                                                 local success, errtype, err = self:set_affiliation(actor, item.attr.jid, item.attr.affiliation, callback, reason);
 760                                                 if not success then origin.send(st.error_reply(stanza, errtype, err)); end
 761                                         elseif item.attr.role and item.attr.nick and not item.attr.affiliation then
 762                                                 local success, errtype, err = self:set_role(actor, self.jid.."/"..item.attr.nick, item.attr.role, callback, reason);
 763                                                 if not success then origin.send(st.error_reply(stanza, errtype, err)); end
 764                                         else
 765                                                 origin.send(st.error_reply(stanza, "cancel", "bad-request"));
 766                                         end
 767                                 elseif type == "get" then
 768                                         local _aff = item.attr.affiliation;
 769                                         local _rol = item.attr.role;
 770                                         if _aff and not _rol then
 771                                                 if affiliation == "owner" or (affiliation == "admin" and _aff ~= "owner" and _aff ~= "admin") then
 772                                                         local reply = st.reply(stanza):query("http://jabber.org/protocol/muc#admin");
 773                                                         for jid, affiliation in pairs(self._affiliations) do
 774                                                                 if affiliation == _aff then
 775                                                                         reply:tag("item", {affiliation = _aff, jid = jid}):up();
 776                                                                 end
 777                                                         end
 778                                                         origin.send(reply);
 779                                                 else
 780                                                         origin.send(st.error_reply(stanza, "auth", "forbidden"));
 781                                                 end
 782                                         elseif _rol and not _aff then
 783                                                 if role == "moderator" then
 784                                                         -- TODO allow admins and owners not in room? Provide read-only access to everyone who can see the participants anyway?
 785                                                         if _rol == "none" then _rol = nil; end
 786                                                         local reply = st.reply(stanza):query("http://jabber.org/protocol/muc#admin");
 787                                                         for occupant_jid, occupant in pairs(self._occupants) do
 788                                                                 if occupant.role == _rol then
 789                                                                         reply:tag("item", {
 790                                                                                 nick = select(3, jid_split(occupant_jid)),
 791                                                                                 role = _rol or "none",
 792                                                                                 affiliation = occupant.affiliation or "none",
 793                                                                                 jid = occupant.jid
 794                                                                                 }):up();
 795                                                                 end
 796                                                         end
 797                                                         origin.send(reply);
 798                                                 else
 799                                                         origin.send(st.error_reply(stanza, "auth", "forbidden"));
 800                                                 end
 801                                         else
 802                                                 origin.send(st.error_reply(stanza, "cancel", "bad-request"));
 803                                         end
 804                                 end
 805                         elseif type == "set" or type == "get" then
 806                                 origin.send(st.error_reply(stanza, "cancel", "bad-request"));
 807                         end
 808                 elseif xmlns == "http://jabber.org/protocol/muc#owner" and (type == "get" or type == "set") and stanza.tags[1].name == "query" then
 809                         if self:get_affiliation(stanza.attr.from) ~= "owner" then
 810                                 origin.send(st.error_reply(stanza, "auth", "forbidden", "Only owners can configure rooms"));
 811                         elseif stanza.attr.type == "get" then
 812                                 self:send_form(origin, stanza);
 813                         elseif stanza.attr.type == "set" then
 814                                 local child = stanza.tags[1].tags[1];
 815                                 if not child then
 816                                         origin.send(st.error_reply(stanza, "modify", "bad-request"));
 817                                 elseif child.name == "destroy" then
 818                                         local newjid = child.attr.jid;
 819                                         local reason, password;
 820                                         for _,tag in ipairs(child.tags) do
 821                                                 if tag.name == "reason" then
 822                                                         reason = #tag.tags == 0 and tag[1];
 823                                                 elseif tag.name == "password" then
 824                                                         password = #tag.tags == 0 and tag[1];
 825                                                 end
 826                                         end
 827                                         self:destroy(newjid, reason, password);
 828                                         origin.send(st.reply(stanza));
 829                                 else
 830                                         self:process_form(origin, stanza);
 831                                 end
 832                         end
 833                 elseif type == "set" or type == "get" then
 834                         origin.send(st.error_reply(stanza, "cancel", "service-unavailable"));
 835                 end
 836         elseif stanza.name == "message" and type == "groupchat" then
 837                 local from = stanza.attr.from;
 838                 local current_nick = self._jid_nick[from];
 839                 local occupant = self._occupants[current_nick];
 840                 if not occupant then -- not in room
 841                         origin.send(st.error_reply(stanza, "cancel", "not-acceptable"));
 842                 elseif occupant.role == "visitor" then
 843                         origin.send(st.error_reply(stanza, "auth", "forbidden"));
 844                 else
 845                         local from = stanza.attr.from;
 846                         stanza.attr.from = current_nick;
 847                         local subject = stanza:get_child_text("subject");
 848                         if subject then
 849                                 if occupant.role == "moderator" or
 850                                         ( self._data.changesubject and occupant.role == "participant" ) then -- and participant
 851                                         self:set_subject(current_nick, subject); -- TODO use broadcast_message_stanza
 852                                 else
 853                                         stanza.attr.from = from;
 854                                         origin.send(st.error_reply(stanza, "auth", "forbidden"));
 855                                 end
 856                         else
 857                                 self:broadcast_message(stanza, self:get_historylength() > 0 and stanza:get_child("body"));
 858                         end
 859                         stanza.attr.from = from;
 860                 end
 861         elseif stanza.name == "message" and type == "error" and is_kickable_error(stanza) then
 862                 local current_nick = self._jid_nick[stanza.attr.from];
 863                 log("debug", "%s kicked from %s for sending an error message", current_nick, self.jid);
 864                 self:handle_to_occupant(origin, build_unavailable_presence_from_error(stanza)); -- send unavailable
 865         elseif stanza.name == "presence" then -- hack - some buggy clients send presence updates to the room rather than their nick
 866                 local to = stanza.attr.to;
 867                 local current_nick = self._jid_nick[stanza.attr.from];
 868                 if current_nick then
 869                         stanza.attr.to = current_nick;
 870                         self:handle_to_occupant(origin, stanza);
 871                         stanza.attr.to = to;
 872                 elseif type ~= "error" and type ~= "result" then
 873                         origin.send(st.error_reply(stanza, "cancel", "service-unavailable"));
 874                 end
 875         elseif stanza.name == "message" and not(type == "chat" or type == "error" or type == "groupchat" or type == "headline") and #stanza.tags == 1
 876                 and self._jid_nick[stanza.attr.from] and stanza.tags[1].name == "x" and stanza.tags[1].attr.xmlns == "http://jabber.org/protocol/muc#user" then
 877                 local x = stanza.tags[1];
 878                 local payload = (#x.tags == 1 and x.tags[1]);
 879                 if payload and payload.name == "invite" and payload.attr.to then
 880                         local _from, _to = stanza.attr.from, stanza.attr.to;
 881                         local _invitee = jid_prep(payload.attr.to);
 882                         if _invitee then
 883                                 local _reason = payload.tags[1] and payload.tags[1].name == 'reason' and #payload.tags[1].tags == 0 and payload.tags[1][1];
 884                                 local invite = st.message({from = _to, to = _invitee, id = stanza.attr.id})
 885                                         :tag('x', {xmlns='http://jabber.org/protocol/muc#user'})
 886                                                 :tag('invite', {from=_from})
 887                                                         :tag('reason'):text(_reason or ""):up()
 888                                                 :up();
 889                                                 if self:get_password() then
 890                                                         invite:tag("password"):text(self:get_password()):up();
 891                                                 end
 892                                         invite:up()
 893                                         :tag('x', {xmlns="jabber:x:conference", jid=_to}) -- COMPAT: Some older clients expect this
 894                                                 :text(_reason or "")
 895                                         :up()
 896                                         :tag('body') -- Add a plain message for clients which don't support invites
 897                                                 :text(_from..' invited you to the room '.._to..(_reason and (' ('.._reason..')') or ""))
 898                                         :up();
 899                                 if self:get_members_only() and not self:get_affiliation(_invitee) then
 900                                         log("debug", "%s invited %s into members only room %s, granting membership", _from, _invitee, _to);
 901                                         self:set_affiliation(_from, _invitee, "member", nil, "Invited by " .. self._jid_nick[_from])
 902                                 end
 903                                 self:_route_stanza(invite);
 904                         else
 905                                 origin.send(st.error_reply(stanza, "cancel", "jid-malformed"));
 906                         end
 907                 else
 908                         origin.send(st.error_reply(stanza, "cancel", "bad-request"));
 909                 end
 910         else
 911                 if type == "error" or type == "result" then return; end
 912                 origin.send(st.error_reply(stanza, "cancel", "service-unavailable"));
 913         end
 914 end
 915
 916 function room_mt:handle_stanza(origin, stanza)
 917         local to_node, to_host, to_resource = jid_split(stanza.attr.to);
 918         if to_resource then
 919                 self:handle_to_occupant(origin, stanza);
 920         else
 921                 self:handle_to_room(origin, stanza);
 922         end
 923 end
 924
 925 function room_mt:route_stanza(stanza) end -- Replace with a routing function, e.g., function(room, stanza) core_route_stanza(origin, stanza); end
 926
 927 function room_mt:get_affiliation(jid)
 928         local node, host, resource = jid_split(jid);
 929         local bare = node and node.."@"..host or host;
 930         local result = self._affiliations[bare]; -- Affiliations are granted, revoked, and maintained based on the user's bare JID.
 931         if not result and self._affiliations[host] == "outcast" then result = "outcast"; end -- host banned
 932         return result;
 933 end
 934 function room_mt:set_affiliation(actor, jid, affiliation, callback, reason)
 935         jid = jid_bare(jid);
 936         if affiliation == "none" then affiliation = nil; end
 937         if affiliation and affiliation ~= "outcast" and affiliation ~= "owner" and affiliation ~= "admin" and affiliation ~= "member" then
 938                 return nil, "modify", "not-acceptable";
 939         end
 940         if actor ~= true then
 941                 local actor_affiliation = self:get_affiliation(actor);
 942                 local target_affiliation = self:get_affiliation(jid);
 943                 if target_affiliation == affiliation then -- no change, shortcut
 944                         if callback then callback(); end
 945                         return true;
 946                 end
 947                 if actor_affiliation ~= "owner" then
 948                         if affiliation == "owner" or affiliation == "admin" or actor_affiliation ~= "admin" or target_affiliation == "owner" or target_affiliation == "admin" then
 949                                 return nil, "cancel", "not-allowed";
 950                         end
 951                 elseif target_affiliation == "owner" and jid_bare(actor) == jid then -- self change
 952                         local is_last = true;
 953                         for j, aff in pairs(self._affiliations) do if j ~= jid and aff == "owner" then is_last = false; break; end end
 954                         if is_last then
 955                                 return nil, "cancel", "conflict";
 956                         end
 957                 end
 958         end
 959         self._affiliations[jid] = affiliation;
 960         local role = self:get_default_role(affiliation);
 961         local x = st.stanza("x", {xmlns = "http://jabber.org/protocol/muc#user"})
 962                         :tag("item", {affiliation=affiliation or "none", role=role or "none"})
 963                                 :tag("reason"):text(reason or ""):up()
 964                         :up();
 965         local presence_type = nil;
 966         if not role then -- getting kicked
 967                 presence_type = "unavailable";
 968                 if affiliation == "outcast" then
 969                         x:tag("status", {code="301"}):up(); -- banned
 970                 else
 971                         x:tag("status", {code="321"}):up(); -- affiliation change
 972                 end
 973         end
 974         local modified_nicks = {};
 975         for nick, occupant in pairs(self._occupants) do
 976                 if jid_bare(occupant.jid) == jid then
 977                         if not role then -- getting kicked
 978                                 self._occupants[nick] = nil;
 979                         else
 980                                 occupant.affiliation, occupant.role = affiliation, role;
 981                         end
 982                         for jid,pres in pairs(occupant.sessions) do -- remove for all sessions of the nick
 983                                 if not role then self._jid_nick[jid] = nil; end
 984                                 local p = st.clone(pres);
 985                                 p.attr.from = nick;
 986                                 p.attr.type = presence_type;
 987                                 p.attr.to = jid;
 988                                 p:add_child(x);
 989                                 self:_route_stanza(p);
 990                                 if occupant.jid == jid then
 991                                         modified_nicks[nick] = p;
 992                                 end
 993                         end
 994                 end
 995         end
 996         if self.save then self:save(); end
 997         if callback then callback(); end
 998         for nick,p in pairs(modified_nicks) do
 999                 p.attr.from = nick;
1000                 self:broadcast_except_nick(p, nick);
1001         end
1002         return true;
1003 end
1004
1005 function room_mt:get_role(nick)
1006         local session = self._occupants[nick];
1007         return session and session.role or nil;
1008 end
1009 function room_mt:can_set_role(actor_jid, occupant_jid, role)
1010         local occupant = self._occupants[occupant_jid];
1011         if not occupant or not actor_jid then return nil, "modify", "not-acceptable"; end
1012
1013         if actor_jid == true then return true; end
1014
1015         local actor = self._occupants[self._jid_nick[actor_jid]];
1016         if actor.role == "moderator" then
1017                 if occupant.affiliation ~= "owner" and occupant.affiliation ~= "admin" then
1018                         if actor.affiliation == "owner" or actor.affiliation == "admin" then
1019                                 return true;
1020                         elseif occupant.role ~= "moderator" and role ~= "moderator" then
1021                                 return true;
1022                         end
1023                 end
1024         end
1025         return nil, "cancel", "not-allowed";
1026 end
1027 function room_mt:set_role(actor, occupant_jid, role, callback, reason)
1028         if role == "none" then role = nil; end
1029         if role and role ~= "moderator" and role ~= "participant" and role ~= "visitor" then return nil, "modify", "not-acceptable"; end
1030         local allowed, err_type, err_condition = self:can_set_role(actor, occupant_jid, role);
1031         if not allowed then return allowed, err_type, err_condition; end
1032         local occupant = self._occupants[occupant_jid];
1033         local x = st.stanza("x", {xmlns = "http://jabber.org/protocol/muc#user"})
1034                         :tag("item", {affiliation=occupant.affiliation or "none", nick=select(3, jid_split(occupant_jid)), role=role or "none"})
1035                                 :tag("reason"):text(reason or ""):up()
1036                         :up();
1037         local presence_type = nil;
1038         if not role then -- kick
1039                 presence_type = "unavailable";
1040                 self._occupants[occupant_jid] = nil;
1041                 for jid in pairs(occupant.sessions) do -- remove for all sessions of the nick
1042                         self._jid_nick[jid] = nil;
1043                 end
1044                 x:tag("status", {code = "307"}):up();
1045         else
1046                 occupant.role = role;
1047         end
1048         local bp;
1049         for jid,pres in pairs(occupant.sessions) do -- send to all sessions of the nick
1050                 local p = st.clone(pres);
1051                 p.attr.from = occupant_jid;
1052                 p.attr.type = presence_type;
1053                 p.attr.to = jid;
1054                 p:add_child(x);
1055                 self:_route_stanza(p);
1056                 if occupant.jid == jid then
1057                         bp = p;
1058                 end
1059         end
1060         if callback then callback(); end
1061         if bp then
1062                 self:broadcast_except_nick(bp, occupant_jid);
1063         end
1064         return true;
1065 end
1066
1067 function room_mt:_route_stanza(stanza)
1068         local muc_child;
1069         local to_occupant = self._occupants[self._jid_nick[stanza.attr.to]];
1070         local from_occupant = self._occupants[stanza.attr.from];
1071         if stanza.name == "presence" then
1072                 if to_occupant and from_occupant then
1073                         if self._data.whois == 'anyone' then
1074                             muc_child = stanza:get_child("x", "http://jabber.org/protocol/muc#user");
1075                         else
1076                                 if to_occupant.role == "moderator" or jid_bare(to_occupant.jid) == jid_bare(from_occupant.jid) then
1077                                         muc_child = stanza:get_child("x", "http://jabber.org/protocol/muc#user");
1078                                 end
1079                         end
1080                 end
1081         end
1082         if muc_child then
1083                 for _, item in pairs(muc_child.tags) do
1084                         if item.name == "item" then
1085                                 if from_occupant == to_occupant then
1086                                         item.attr.jid = stanza.attr.to;
1087                                 else
1088                                         item.attr.jid = from_occupant.jid;
1089                                 end
1090                         end
1091                 end
1092         end
1093         self:route_stanza(stanza);
1094         if muc_child then
1095                 for _, item in pairs(muc_child.tags) do
1096                         if item.name == "item" then
1097                                 item.attr.jid = nil;
1098                         end
1099                 end
1100         end
1101 end
1102
1103 local _M = {}; -- module "muc"
1104
1105 function _M.new_room(jid, config)
1106         return setmetatable({
1107                 jid = jid;
1108                 _jid_nick = {};
1109                 _occupants = {};
1110                 _data = {
1111                     whois = 'moderators';
1112                     history_length = math.min((config and config.history_length)
1113                         or default_history_length, max_history_length);
1114                 };
1115                 _affiliations = {};
1116         }, room_mt);
1117 end
1118
1119 function _M.set_max_history_length(_max_history_length)
1120         max_history_length = _max_history_length or math.huge;
1121 end
1122
1123 _M.room_mt = room_mt;
1124
1125 return _M;