core/stanza_router.lua

   1
   2 -- The code in this file should be self-explanatory, though the logic is horrible
   3 -- for more info on that, see doc/stanza_routing.txt, which attempts to condense
   4 -- the rules from the RFCs (mainly 3921)
   5
   6 require "core.servermanager"
   7
   8 local log = require "util.logger".init("stanzarouter")
   9
  10 local st = require "util.stanza";
  11 local send_s2s = require "core.s2smanager".send_to_host;
  12 local user_exists = require "core.usermanager".user_exists;
  13
  14 local rostermanager = require "core.rostermanager";
  15 local sessionmanager = require "core.sessionmanager";
  16
  17 local s2s_verify_dialback = require "core.s2smanager".verify_dialback;
  18 local s2s_make_authenticated = require "core.s2smanager".make_authenticated;
  19
  20 local modules_handle_stanza = require "core.modulemanager".handle_stanza;
  21
  22 local format = string.format;
  23 local tostring = tostring;
  24
  25 local jid_split = require "util.jid".split;
  26 local print = print;
  27
  28 function core_process_stanza(origin, stanza)
  29         log("debug", "Received["..origin.type.."]: "..tostring(stanza))
  30         -- TODO verify validity of stanza (as well as JID validity)
  31         if stanza.name == "iq" and not(#stanza.tags == 1 and stanza.tags[1].attr.xmlns) then
  32                 if stanza.attr.type == "set" or stanza.attr.type == "get" then
  33                         error("Invalid IQ");
  34                 elseif #stanza.tags > 1 and not(stanza.attr.type == "error" or stanza.attr.type == "result") then
  35                         error("Invalid IQ");
  36                 end
  37         end
  38
  39         if origin.type == "c2s" and not origin.full_jid
  40                 and not(stanza.name == "iq" and stanza.tags[1].name == "bind"
  41                                 and stanza.tags[1].attr.xmlns == "urn:ietf:params:xml:ns:xmpp-bind") then
  42                 error("Client MUST bind resource after auth");
  43         end
  44
  45         local to = stanza.attr.to;
  46         -- TODO also, stazas should be returned to their original state before the function ends
  47         if origin.type == "c2s" then
  48                 stanza.attr.from = origin.full_jid; -- quick fix to prevent impersonation (FIXME this would be incorrect when the origin is not c2s)
  49         end
  50
  51         if not to then
  52                 core_handle_stanza(origin, stanza);
  53         elseif origin.type == "c2s" and stanza.name == "presence" and stanza.attr.type ~= nil and stanza.attr.type ~= "unavailable" then
  54                 local node, host = jid_split(stanza.attr.to);
  55                 local to_bare = node and (node.."@"..host) or host; -- bare JID
  56                 local from_node, from_host = jid_split(stanza.attr.from);
  57                 local from_bare = from_node and (from_node.."@"..from_host) or from_host; -- bare JID
  58                 handle_outbound_presence_subscriptions_and_probes(origin, stanza, from_bare, to_bare);
  59         elseif hosts[to] and hosts[to].type == "local" then
  60                 core_handle_stanza(origin, stanza);
  61         elseif stanza.name == "iq" and not select(3, jid_split(to)) then
  62                 core_handle_stanza(origin, stanza);
  63         elseif stanza.attr.xmlns and stanza.attr.xmlns ~= "jabber:client" and stanza.attr.xmlns ~= "jabber:server" then
  64                 modules_handle_stanza(origin, stanza);
  65         elseif origin.type == "c2s" or origin.type == "s2sin" then
  66                 core_route_stanza(origin, stanza);
  67         end
  68 end
  69
  70 -- This function handles stanzas which are not routed any further,
  71 -- that is, they are handled by this server
  72 function core_handle_stanza(origin, stanza)
  73         -- Handlers
  74         if modules_handle_stanza(origin, stanza) then return; end
  75         if origin.type == "c2s" or origin.type == "c2s_unauthed" then
  76                 local session = origin;
  77
  78                 if stanza.name == "presence" and origin.roster then
  79                         if stanza.attr.type == nil or stanza.attr.type == "unavailable" then
  80                                 for jid in pairs(origin.roster) do -- broadcast to all interested contacts
  81                                         local subscription = origin.roster[jid].subscription;
  82                                         if subscription == "both" or subscription == "from" then
  83                                                 stanza.attr.to = jid;
  84                                                 core_route_stanza(origin, stanza);
  85                                         end
  86                                 end
  87                                 local node, host = jid_split(stanza.attr.from);
  88                                 for _, res in pairs(hosts[host].sessions[node].sessions) do -- broadcast to all resources
  89                                         if res ~= origin and res.full_jid then -- to resource. FIXME is res.full_jid the correct check? Maybe it should be res.presence
  90                                                 stanza.attr.to = res.full_jid;
  91                                                 core_route_stanza(origin, stanza);
  92                                         end
  93                                 end
  94                                 if not origin.presence then -- presence probes on initial presence -- FIXME does unavailable qualify as initial presence?
  95                                         local probe = st.presence({from = origin.full_jid, type = "probe"});
  96                                         for jid in pairs(origin.roster) do -- probe all contacts we are subscribed to
  97                                                 local subscription = origin.roster[jid].subscription;
  98                                                 if subscription == "both" or subscription == "to" then
  99                                                         probe.attr.to = jid;
 100                                                         core_route_stanza(origin, probe);
 101                                                 end
 102                                         end
 103                                         for _, res in pairs(hosts[host].sessions[node].sessions) do -- broadcast from all resources
 104                                                 if res ~= origin and stanza.attr.type ~= "unavailable" and res.presence then -- FIXME does unavailable qualify as initial presence?
 105                                                         res.presence.attr.to = origin.full_jid;
 106                                                         core_route_stanza(res, res.presence);
 107                                                         res.presence.attr.to = nil;
 108                                                 end
 109                                         end
 110                                         -- TODO resend subscription requests
 111                                 end
 112                                 origin.presence = stanza;
 113                                 stanza.attr.to = nil; -- reset it
 114                         else
 115                                 -- TODO error, bad type
 116                         end
 117                 end
 118         else
 119                 log("warn", "Unhandled origin: %s", origin.type);
 120         end
 121 end
 122
 123 function send_presence_of_available_resources(user, host, jid, recipient_session)
 124         local h = hosts[host];
 125         local count = 0;
 126         if h and h.type == "local" then
 127                 local u = h.sessions[user];
 128                 if u then
 129                         for k, session in pairs(u.sessions) do
 130                                 local pres = session.presence;
 131                                 if pres then
 132                                         pres.attr.to = jid;
 133                                         pres.attr.from = session.full_jid;
 134                                         recipient_session.send(pres);
 135                                         pres.attr.to = nil;
 136                                         pres.attr.from = nil;
 137                                         count = count + 1;
 138                                 end
 139                         end
 140                 end
 141         end
 142         return count;
 143 end
 144
 145 function handle_outbound_presence_subscriptions_and_probes(origin, stanza, from_bare, to_bare)
 146         local node, host = jid_split(from_bare);
 147         local st_from, st_to = stanza.attr.from, stanza.attr.to;
 148         stanza.attr.from, stanza.attr.to = from_bare, to_bare;
 149         if stanza.attr.type == "subscribe" then
 150                 log("debug", "outbound subscribe from "..from_bare.." for "..to_bare);
 151                 -- 1. route stanza
 152                 -- 2. roster push (subscription = none, ask = subscribe)
 153                 if rostermanager.set_contact_pending_out(node, host, to_bare) then
 154                         rostermanager.roster_push(node, host, to_bare);
 155                 end -- else file error
 156                 core_route_stanza(origin, stanza);
 157         elseif stanza.attr.type == "unsubscribe" then
 158                 log("debug", "outbound unsubscribe from "..from_bare.." for "..to_bare);
 159                 -- 1. route stanza
 160                 -- 2. roster push (subscription = none or from)
 161                 if rostermanager.unsubscribe(node, host, to_bare) then
 162                         rostermanager.roster_push(node, host, to_bare); -- FIXME do roster push when roster has in fact not changed?
 163                 end -- else file error
 164                 core_route_stanza(origin, stanza);
 165         elseif stanza.attr.type == "subscribed" then
 166                 log("debug", "outbound subscribed from "..from_bare.." for "..to_bare);
 167                 -- 1. route stanza
 168                 -- 2. roster_push ()
 169                 -- 3. send_presence_of_available_resources
 170                 if rostermanager.subscribed(node, host, to_bare) then
 171                         rostermanager.roster_push(node, host, to_bare);
 172                         core_route_stanza(origin, stanza);
 173                         send_presence_of_available_resources(node, host, to_bare, origin);
 174                 end
 175         elseif stanza.attr.type == "unsubscribed" then
 176                 log("debug", "outbound unsubscribed from "..from_bare.." for "..to_bare);
 177                 -- 1. route stanza
 178                 -- 2. roster push (subscription = none or to)
 179                 if rostermanager.unsubscribed(node, host, to_bare) then
 180                         rostermanager.roster_push(node, host, to_bare);
 181                         core_route_stanza(origin, stanza);
 182                 end
 183         end
 184         stanza.attr.from, stanza.attr.to = st_from, st_to;
 185 end
 186
 187 function handle_inbound_presence_subscriptions_and_probes(origin, stanza, from_bare, to_bare)
 188         local node, host = jid_split(to_bare);
 189         local st_from, st_to = stanza.attr.from, stanza.attr.to;
 190         stanza.attr.from, stanza.attr.to = from_bare, to_bare;
 191         if stanza.attr.type == "probe" then
 192                 if rostermanager.is_contact_subscribed(node, host, from_bare) then
 193                         if 0 == send_presence_of_available_resources(node, host, from_bare, origin) then
 194                                 -- TODO send last recieved unavailable presence (or we MAY do nothing, which is fine too)
 195                         end
 196                 else
 197                         core_route_stanza(origin, st.presence({from=to_bare, to=from_bare, type="unsubscribed"}));
 198                 end
 199         elseif stanza.attr.type == "subscribe" then
 200                 log("debug", "inbound subscribe from "..from_bare.." for "..to_bare);
 201                 if rostermanager.is_contact_subscribed(node, host, from_bare) then
 202                         core_route_stanza(origin, st.presence({from=to_bare, to=from_bare, type="subscribed"})); -- already subscribed
 203                 else
 204                         if not rostermanager.is_contact_pending_in(node, host, from_bare) then
 205                                 if rostermanager.set_contact_pending_in(node, host, from_bare) then
 206                                         sessionmanager.send_to_available_resources(node, host, stanza);
 207                                 end -- TODO else return error, unable to save
 208                         end
 209                 end
 210         elseif stanza.attr.type == "unsubscribe" then
 211                 log("debug", "inbound unsubscribe from "..from_bare.." for "..to_bare);
 212                 if rostermanager.process_inbound_unsubscribe(node, host, from_bare) then
 213                         rostermanager.roster_push(node, host, from_bare);
 214                 end
 215         elseif stanza.attr.type == "subscribed" then
 216                 log("debug", "inbound subscribed from "..from_bare.." for "..to_bare);
 217                 if rostermanager.process_inbound_subscription_approval(node, host, from_bare) then
 218                         rostermanager.roster_push(node, host, from_bare);
 219                 end
 220         elseif stanza.attr.type == "unsubscribed" then
 221                 log("debug", "inbound unsubscribed from "..from_bare.." for "..to_bare);
 222                 if rostermanager.process_inbound_subscription_approval(node, host, from_bare) then
 223                         rostermanager.roster_push(node, host, from_bare);
 224                 end
 225         end -- discard any other type
 226         stanza.attr.from, stanza.attr.to = st_from, st_to;
 227 end
 228
 229 function core_route_stanza(origin, stanza)
 230         -- Hooks
 231         --- ...later
 232
 233         -- Deliver
 234         local to = stanza.attr.to;
 235         local node, host, resource = jid_split(to);
 236         local to_bare = node and (node.."@"..host) or host; -- bare JID
 237         local from = stanza.attr.from;
 238         local from_node, from_host, from_resource = jid_split(from);
 239         local from_bare = from_node and (from_node.."@"..from_host) or from_host; -- bare JID
 240
 241         if stanza.name == "presence" and (stanza.attr.type ~= nil and stanza.attr.type ~= "unavailable") then resource = nil; end
 242
 243         local host_session = hosts[host]
 244         if host_session and host_session.type == "local" then
 245                 -- Local host
 246                 local user = host_session.sessions[node];
 247                 if user then
 248                         local res = user.sessions[resource];
 249                         if not res then
 250                                 -- if we get here, resource was not specified or was unavailable
 251                                 if stanza.name == "presence" then
 252                                         if stanza.attr.type ~= nil and stanza.attr.type ~= "unavailable" then
 253                                                 handle_inbound_presence_subscriptions_and_probes(origin, stanza, from_bare, to_bare);
 254                                         else -- sender is available or unavailable
 255                                                 for k in pairs(user.sessions) do -- presence broadcast to all user resources. FIXME should this be just for available resources? Do we need to check subscription?
 256                                                         if user.sessions[k].full_jid then
 257                                                                 stanza.attr.to = user.sessions[k].full_jid; -- reset at the end of function
 258                                                                 user.sessions[k].send(stanza);
 259                                                         end
 260                                                 end
 261                                         end
 262                                 elseif stanza.name == "message" then -- select a resource to recieve message
 263                                         for k in pairs(user.sessions) do
 264                                                 if user.sessions[k].full_jid then
 265                                                         res = user.sessions[k];
 266                                                         break;
 267                                                 end
 268                                         end
 269                                         -- TODO find resource with greatest priority
 270                                         res.send(stanza);
 271                                 else
 272                                         -- TODO send IQ error
 273                                 end
 274                         else
 275                                 -- User + resource is online...
 276                                 stanza.attr.to = res.full_jid; -- reset at the end of function
 277                                 res.send(stanza); -- Yay \o/
 278                         end
 279                 else
 280                         -- user not online
 281                         if user_exists(node, host) then
 282                                 if stanza.name == "presence" then
 283                                         if stanza.attr.type ~= nil and stanza.attr.type ~= "unavailable" then
 284                                                 handle_inbound_presence_subscriptions_and_probes(origin, stanza, from_bare, to_bare);
 285                                         else
 286                                                 -- TODO send unavailable presence or unsubscribed
 287                                         end
 288                                 elseif stanza.name == "message" then
 289                                         -- TODO send message error, or store offline messages
 290                                 elseif stanza.name == "iq" then
 291                                         -- TODO send IQ error
 292                                 end
 293                         else -- user does not exist
 294                                 -- TODO we would get here for nodeless JIDs too. Do something fun maybe? Echo service? Let plugins use xmpp:server/resource addresses?
 295                                 if stanza.name == "presence" then
 296                                         if stanza.attr.type == "probe" then
 297                                                 origin.send(st.presence({from = to_bare, to = from_bare, type = "unsubscribed"}));
 298                                         end
 299                                         -- else ignore
 300                                 else
 301                                         origin.send(st.error_reply(stanza, "cancel", "service-unavailable"));
 302                                 end
 303                         end
 304                 end
 305         elseif origin.type == "c2s" then
 306                 -- Remote host
 307                 local xmlns = stanza.attr.xmlns;
 308                 --stanza.attr.xmlns = "jabber:server";
 309                 stanza.attr.xmlns = nil;
 310                 log("debug", "sending s2s stanza: %s", tostring(stanza));
 311                 send_s2s(origin.host, host, stanza); -- TODO handle remote routing errors
 312                 stanza.attr.xmlns = xmlns; -- reset
 313         else
 314                 log("warn", "received stanza from unhandled connection type: %s", origin.type);
 315         end
 316         stanza.attr.to = to; -- reset
 317 end
 318
 319 function handle_stanza_toremote(stanza)
 320         log("error", "Stanza bound for remote host, but s2s is not implemented");
 321 end