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