plugins/mod_privacy.lua

   1 -- Prosody IM
   2 -- Copyright (C) 2009-2010 Matthew Wild
   3 -- Copyright (C) 2009-2010 Waqas Hussain
   4 -- Copyright (C) 2009 Thilo Cestonaro
   5 --
   6 -- This project is MIT/X11 licensed. Please see the
   7 -- COPYING file in the source package for more information.
   8 --
   9
  10 module:add_feature("jabber:iq:privacy");
  11
  12 local prosody = prosody;
  13 local st = require "util.stanza";
  14 local datamanager = require "util.datamanager";
  15 local bare_sessions, full_sessions = bare_sessions, full_sessions;
  16 local util_Jid = require "util.jid";
  17 local jid_bare = util_Jid.bare;
  18 local jid_split, jid_join = util_Jid.split, util_Jid.join;
  19 local load_roster = require "core.rostermanager".load_roster;
  20 local to_number = tonumber;
  21
  22 function isListUsed(origin, name, privacy_lists)
  23         local user = bare_sessions[origin.username.."@"..origin.host];
  24         if user then
  25                 for resource, session in pairs(user.sessions) do
  26                         if resource ~= origin.resource then
  27                                 if session.activePrivacyList == name then
  28                                         return true;
  29                                 elseif session.activePrivacyList == nil and privacy_lists.default == name then
  30                                         return true;
  31                                 end
  32                         end
  33                 end
  34         end
  35 end
  36
  37 function isAnotherSessionUsingDefaultList(origin)
  38         local user = bare_sessions[origin.username.."@"..origin.host];
  39         if user then
  40                 for resource, session in pairs(user.sessions) do
  41                         if resource ~= origin.resource and session.activePrivacyList == nil then
  42                                 return true;
  43                         end
  44                 end
  45         end
  46 end
  47
  48 function sendUnavailable(origin, to, from)
  49 --[[ example unavailable presence stanza
  50 <presence from="node@host/resource" type="unavailable" to="node@host" >
  51         <status>Logged out</status>
  52 </presence>
  53 ]]--
  54         local presence = st.presence({from=from, type="unavailable"});
  55         presence:tag("status"):text("Logged out");
  56
  57         local node, host = jid_bare(to);
  58         local bare = node .. "@" .. host;
  59
  60         local user = bare_sessions[bare];
  61         if user then
  62                 for resource, session in pairs(user.sessions) do
  63                         presence.attr.to = session.full_jid;
  64                         module:log("debug", "send unavailable to: %s; from: %s", tostring(presence.attr.to), tostring(presence.attr.from));
  65                         origin.send(presence);
  66                 end
  67         end
  68 end
  69
  70 function declineList(privacy_lists, origin, stanza, which)
  71         if which == "default" then
  72                 if isAnotherSessionUsingDefaultList(origin) then
  73                         return { "cancel", "conflict", "Another session is online and using the default list."};
  74                 end
  75                 privacy_lists.default = nil;
  76                 origin.send(st.reply(stanza));
  77         elseif which == "active" then
  78                 origin.activePrivacyList = nil;
  79                 origin.send(st.reply(stanza));
  80         else
  81                 return {"modify", "bad-request", "Neither default nor active list specifed to decline."};
  82         end
  83         return true;
  84 end
  85
  86 function activateList(privacy_lists, origin, stanza, which, name)
  87         local list = privacy_lists.lists[name];
  88
  89         if which == "default" and list then
  90                 if isAnotherSessionUsingDefaultList(origin) then
  91                         return {"cancel", "conflict", "Another session is online and using the default list."};
  92                 end
  93                 privacy_lists.default = name;
  94                 origin.send(st.reply(stanza));
  95         elseif which == "active" and list then
  96                 origin.activePrivacyList = name;
  97                 origin.send(st.reply(stanza));
  98         elseif not list then
  99                 return {"cancel", "item-not-found", "No such list: "..name};
 100         else
 101                 return {"modify", "bad-request", "No list chosen to be active or default."};
 102         end
 103         return true;
 104 end
 105
 106 function deleteList(privacy_lists, origin, stanza, name)
 107         local list = privacy_lists.lists[name];
 108
 109         if list then
 110                 if isListUsed(origin, name, privacy_lists) then
 111                         return {"cancel", "conflict", "Another session is online and using the list which should be deleted."};
 112                 end
 113                 if privacy_lists.default == name then
 114                         privacy_lists.default = nil;
 115                 end
 116                 if origin.activePrivacyList == name then
 117                         origin.activePrivacyList = nil;
 118                 end
 119                 privacy_lists.lists[name] = nil;
 120                 origin.send(st.reply(stanza));
 121                 return true;
 122         end
 123         return {"modify", "bad-request", "Not existing list specifed to be deleted."};
 124 end
 125
 126 function createOrReplaceList (privacy_lists, origin, stanza, name, entries, roster)
 127         local bare_jid = origin.username.."@"..origin.host;
 128
 129         if privacy_lists.lists == nil then
 130                 privacy_lists.lists = {};
 131         end
 132
 133         local list = {};
 134         privacy_lists.lists[name] = list;
 135
 136         local orderCheck = {};
 137         list.name = name;
 138         list.items = {};
 139
 140         for _,item in ipairs(entries) do
 141                 if to_number(item.attr.order) == nil or to_number(item.attr.order) < 0 or orderCheck[item.attr.order] ~= nil then
 142                         return {"modify", "bad-request", "Order attribute not valid."};
 143                 end
 144
 145                 if item.attr.type ~= nil and item.attr.type ~= "jid" and item.attr.type ~= "subscription" and item.attr.type ~= "group" then
 146                         return {"modify", "bad-request", "Type attribute not valid."};
 147                 end
 148
 149                 local tmp = {};
 150                 orderCheck[item.attr.order] = true;
 151
 152                 tmp["type"] = item.attr.type;
 153                 tmp["value"] = item.attr.value;
 154                 tmp["action"] = item.attr.action;
 155                 tmp["order"] = to_number(item.attr.order);
 156                 tmp["presence-in"] = false;
 157                 tmp["presence-out"] = false;
 158                 tmp["message"] = false;
 159                 tmp["iq"] = false;
 160
 161                 if #item.tags > 0 then
 162                         for _,tag in ipairs(item.tags) do
 163                                 tmp[tag.name] = true;
 164                         end
 165                 end
 166
 167                 if tmp.type == "subscription" then
 168                         if      tmp.value ~= "both" and
 169                                 tmp.value ~= "to" and
 170                                 tmp.value ~= "from" and
 171                                 tmp.value ~= "none" then
 172                                 return {"cancel", "bad-request", "Subscription value must be both, to, from or none."};
 173                         end
 174                 end
 175
 176                 if tmp.action ~= "deny" and tmp.action ~= "allow" then
 177                         return {"cancel", "bad-request", "Action must be either deny or allow."};
 178                 end
 179                 list.items[#list.items + 1] = tmp;
 180         end
 181
 182         table.sort(list, function(a, b) return a.order < b.order; end);
 183
 184         origin.send(st.reply(stanza));
 185         if bare_sessions[bare_jid] ~= nil then
 186                 local iq = st.iq ( { type = "set", id="push1" } );
 187                 iq:tag ("query", { xmlns = "jabber:iq:privacy" } );
 188                 iq:tag ("list", { name = list.name } ):up();
 189                 iq:up();
 190                 for resource, session in pairs(bare_sessions[bare_jid].sessions) do
 191                         iq.attr.to = bare_jid.."/"..resource
 192                         session.send(iq);
 193                 end
 194         else
 195                 return {"cancel", "bad-request", "internal error."};
 196         end
 197         return true;
 198 end
 199
 200 function getList(privacy_lists, origin, stanza, name)
 201         local reply = st.reply(stanza);
 202         reply:tag("query", {xmlns="jabber:iq:privacy"});
 203
 204         if name == nil then
 205                 if privacy_lists.lists then
 206                         if origin.activePrivacyList then
 207                                 reply:tag("active", {name=origin.activePrivacyList}):up();
 208                         end
 209                         if privacy_lists.default then
 210                                 reply:tag("default", {name=privacy_lists.default}):up();
 211                         end
 212                         for name,list in pairs(privacy_lists.lists) do
 213                                 reply:tag("list", {name=name}):up();
 214                         end
 215                 end
 216         else
 217                 local list = privacy_lists.lists[name];
 218                 if list then
 219                         reply = reply:tag("list", {name=list.name});
 220                         for _,item in ipairs(list.items) do
 221                                 reply:tag("item", {type=item.type, value=item.value, action=item.action, order=item.order});
 222                                 if item["message"] then reply:tag("message"):up(); end
 223                                 if item["iq"] then reply:tag("iq"):up(); end
 224                                 if item["presence-in"] then reply:tag("presence-in"):up(); end
 225                                 if item["presence-out"] then reply:tag("presence-out"):up(); end
 226                                 reply:up();
 227                         end
 228                 else
 229                         return {"cancel", "item-not-found", "Unknown list specified."};
 230                 end
 231         end
 232
 233         origin.send(reply);
 234         return true;
 235 end
 236
 237 module:hook("iq/bare/jabber:iq:privacy:query", function(data)
 238         local origin, stanza = data.origin, data.stanza;
 239
 240         if stanza.attr.to == nil then -- only service requests to own bare JID
 241                 local query = stanza.tags[1]; -- the query element
 242                 local valid = false;
 243                 local privacy_lists = datamanager.load(origin.username, origin.host, "privacy") or { lists = {} };
 244
 245                 if privacy_lists.lists[1] then -- Code to migrate from old privacy lists format, remove in 0.8
 246                         module:log("info", "Upgrading format of stored privacy lists for %s@%s", origin.username, origin.host);
 247                         local lists = privacy_lists.lists;
 248                         for idx, list in ipairs(lists) do
 249                                 lists[list.name] = list;
 250                                 lists[idx] = nil;
 251                         end
 252                 end
 253
 254                 if stanza.attr.type == "set" then
 255                         if #query.tags == 1 then --  the <query/> element MUST NOT include more than one child element
 256                                 for _,tag in ipairs(query.tags) do
 257                                         if tag.name == "active" or tag.name == "default" then
 258                                                 if tag.attr.name == nil then -- Client declines the use of active / default list
 259                                                         valid = declineList(privacy_lists, origin, stanza, tag.name);
 260                                                 else -- Client requests change of active / default list
 261                                                         valid = activateList(privacy_lists, origin, stanza, tag.name, tag.attr.name);
 262                                                 end
 263                                         elseif tag.name == "list" and tag.attr.name then -- Client adds / edits a privacy list
 264                                                 if #tag.tags == 0 then -- Client removes a privacy list
 265                                                         valid = deleteList(privacy_lists, origin, stanza, tag.attr.name);
 266                                                 else -- Client edits a privacy list
 267                                                         valid = createOrReplaceList(privacy_lists, origin, stanza, tag.attr.name, tag.tags);
 268                                                 end
 269                                         end
 270                                 end
 271                         end
 272                 elseif stanza.attr.type == "get" then
 273                         local name = nil;
 274                         local listsToRetrieve = 0;
 275                         if #query.tags >= 1 then
 276                                 for _,tag in ipairs(query.tags) do
 277                                         if tag.name == "list" then -- Client requests a privacy list from server
 278                                                 name = tag.attr.name;
 279                                                 listsToRetrieve = listsToRetrieve + 1;
 280                                         end
 281                                 end
 282                         end
 283                         if listsToRetrieve == 0 or listsToRetrieve == 1 then
 284                                 valid = getList(privacy_lists, origin, stanza, name);
 285                         end
 286                 end
 287
 288                 if valid ~= true then
 289                         valid = valid or { "cancel", "bad-request", "Couldn't understand request" };
 290                         if valid[1] == nil then
 291                                 valid[1] = "cancel";
 292                         end
 293                         if valid[2] == nil then
 294                                 valid[2] = "bad-request";
 295                         end
 296                         origin.send(st.error_reply(stanza, valid[1], valid[2], valid[3]));
 297                 else
 298                         datamanager.store(origin.username, origin.host, "privacy", privacy_lists);
 299                 end
 300                 return true;
 301         end
 302 end);
 303
 304 function checkIfNeedToBeBlocked(e, session)
 305         local origin, stanza = e.origin, e.stanza;
 306         local privacy_lists = datamanager.load(session.username, session.host, "privacy") or {};
 307         local bare_jid = session.username.."@"..session.host;
 308         local to = stanza.attr.to or bare_jid;
 309         local from = stanza.attr.from;
 310
 311         local is_to_user = bare_jid == jid_bare(to);
 312         local is_from_user = bare_jid == jid_bare(from);
 313
 314         --module:log("debug", "stanza: %s, to: %s, from: %s", tostring(stanza.name), tostring(to), tostring(from));
 315
 316         if privacy_lists.lists == nil or
 317                 not (session.activePrivacyList or privacy_lists.default)
 318         then
 319                 return; -- Nothing to block, default is Allow all
 320         end
 321         if is_from_user and is_to_user then
 322                 --module:log("debug", "Not blocking communications between user's resources");
 323                 return; -- from one of a user's resource to another => HANDS OFF!
 324         end
 325
 326         local item;
 327         local listname = session.activePrivacyList;
 328         if listname == nil then
 329                 listname = privacy_lists.default; -- no active list selected, use default list
 330         end
 331         local list = privacy_lists.lists[listname];
 332         if not list then -- should never happen
 333                 module:log("warn", "given privacy list not found. name: %s for user %s", listname, bare_jid);
 334                 return;
 335         end
 336         for _,item in ipairs(list.items) do
 337                 local apply = false;
 338                 local block = false;
 339                 if (
 340                         (stanza.name == "message" and item.message) or
 341                         (stanza.name == "iq" and item.iq) or
 342                         (stanza.name == "presence" and is_to_user and item["presence-in"]) or
 343                         (stanza.name == "presence" and is_from_user and item["presence-out"]) or
 344                         (item.message == false and item.iq == false and item["presence-in"] == false and item["presence-out"] == false)
 345                 ) then
 346                         apply = true;
 347                 end
 348                 if apply then
 349                         local evilJid = {};
 350                         apply = false;
 351                         if is_to_user then
 352                                 --module:log("debug", "evil jid is (from): %s", from);
 353                                 evilJid.node, evilJid.host, evilJid.resource = jid_split(from);
 354                         else
 355                                 --module:log("debug", "evil jid is (to): %s", to);
 356                                 evilJid.node, evilJid.host, evilJid.resource = jid_split(to);
 357                         end
 358                         if      item.type == "jid" and
 359                                 (evilJid.node and evilJid.host and evilJid.resource and item.value == evilJid.node.."@"..evilJid.host.."/"..evilJid.resource) or
 360                                 (evilJid.node and evilJid.host and item.value == evilJid.node.."@"..evilJid.host) or
 361                                 (evilJid.host and evilJid.resource and item.value == evilJid.host.."/"..evilJid.resource) or
 362                                 (evilJid.host and item.value == evilJid.host) then
 363                                 apply = true;
 364                                 block = (item.action == "deny");
 365                         elseif item.type == "group" then
 366                                 local roster = load_roster(session.username, session.host);
 367                                 local roster_entry = roster[jid_join(evilJid.node, evilJid.host)];
 368                                 if roster_entry then
 369                                         local groups = roster_entry.groups;
 370                                         for group in pairs(groups) do
 371                                                 if group == item.value then
 372                                                         apply = true;
 373                                                         block = (item.action == "deny");
 374                                                         break;
 375                                                 end
 376                                         end
 377                                 end
 378                         elseif item.type == "subscription" then -- we need a valid bare evil jid
 379                                 local roster = load_roster(session.username, session.host);
 380                                 local roster_entry = roster[jid_join(evilJid.node, evilJid.host)];
 381                                 if (not(roster_entry) and item.value == "none")
 382                                    or (roster_entry and roster_entry.subscription == item.value) then
 383                                         apply = true;
 384                                         block = (item.action == "deny");
 385                                 end
 386                         elseif item.type == nil then
 387                                 apply = true;
 388                                 block = (item.action == "deny");
 389                         end
 390                 end
 391                 if apply then
 392                         if block then
 393                                 module:log("debug", "stanza blocked: %s, to: %s, from: %s", tostring(stanza.name), tostring(to), tostring(from));
 394                                 if stanza.name == "message" then
 395                                         origin.send(st.error_reply(stanza, "cancel", "service-unavailable"));
 396                                 elseif stanza.name == "iq" and (stanza.attr.type == "get" or stanza.attr.type == "set") then
 397                                         origin.send(st.error_reply(stanza, "cancel", "service-unavailable"));
 398                                 end
 399                                 return true; -- stanza blocked !
 400                         else
 401                                 --module:log("debug", "stanza explicitly allowed!")
 402                                 return;
 403                         end
 404                 end
 405         end
 406 end
 407
 408 function preCheckIncoming(e)
 409         local session;
 410         if e.stanza.attr.to ~= nil then
 411                 local node, host, resource = jid_split(e.stanza.attr.to);
 412                 if node == nil or host == nil then
 413                         return;
 414                 end
 415                 if resource == nil then
 416                         local prio = 0;
 417                         local session_;
 418                         if bare_sessions[node.."@"..host] ~= nil then
 419                                 for resource, session_ in pairs(bare_sessions[node.."@"..host].sessions) do
 420                                         if session_.priority ~= nil and session_.priority > prio then
 421                                                 session = session_;
 422                                                 prio = session_.priority;
 423                                         end
 424                                 end
 425                         end
 426                 else
 427                         session = full_sessions[node.."@"..host.."/"..resource];
 428                 end
 429                 if session ~= nil then
 430                         return checkIfNeedToBeBlocked(e, session);
 431                 else
 432                         --module:log("debug", "preCheckIncoming: Couldn't get session for jid: %s@%s/%s", tostring(node), tostring(host), tostring(resource));
 433                 end
 434         end
 435 end
 436
 437 function preCheckOutgoing(e)
 438         local session = e.origin;
 439         if e.stanza.attr.from == nil then
 440                 e.stanza.attr.from = session.username .. "@" .. session.host;
 441                 if session.resource ~= nil then
 442                         e.stanza.attr.from = e.stanza.attr.from .. "/" .. session.resource;
 443                 end
 444         end
 445         if session.username then -- FIXME do properly
 446                 return checkIfNeedToBeBlocked(e, session);
 447         end
 448 end
 449
 450 module:hook("pre-message/full", preCheckOutgoing, 500);
 451 module:hook("pre-message/bare", preCheckOutgoing, 500);
 452 module:hook("pre-message/host", preCheckOutgoing, 500);
 453 module:hook("pre-iq/full", preCheckOutgoing, 500);
 454 module:hook("pre-iq/bare", preCheckOutgoing, 500);
 455 module:hook("pre-iq/host", preCheckOutgoing, 500);
 456 module:hook("pre-presence/full", preCheckOutgoing, 500);
 457 module:hook("pre-presence/bare", preCheckOutgoing, 500);
 458 module:hook("pre-presence/host", preCheckOutgoing, 500);
 459
 460 module:hook("message/full", preCheckIncoming, 500);
 461 module:hook("message/bare", preCheckIncoming, 500);
 462 module:hook("message/host", preCheckIncoming, 500);
 463 module:hook("iq/full", preCheckIncoming, 500);
 464 module:hook("iq/bare", preCheckIncoming, 500);
 465 module:hook("iq/host", preCheckIncoming, 500);
 466 module:hook("presence/full", preCheckIncoming, 500);
 467 module:hook("presence/bare", preCheckIncoming, 500);
 468 module:hook("presence/host", preCheckIncoming, 500);