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