plugins/mod_dialback.lua

   1 -- Prosody IM v0.2
   2 -- Copyright (C) 2008 Matthew Wild
   3 -- Copyright (C) 2008 Waqas Hussain
   4 --
   5 -- This program is free software; you can redistribute it and/or
   6 -- modify it under the terms of the GNU General Public License
   7 -- as published by the Free Software Foundation; either version 2
   8 -- of the License, or (at your option) any later version.
   9 --
  10 -- This program is distributed in the hope that it will be useful,
  11 -- but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 -- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 -- GNU General Public License for more details.
  14 --
  15 -- You should have received a copy of the GNU General Public License
  16 -- along with this program; if not, write to the Free Software
  17 -- Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  18 --
  19
  20
  21
  22 local send_s2s = require "core.s2smanager".send_to_host;
  23 local s2s_make_authenticated = require "core.s2smanager".make_authenticated;
  24 local s2s_verify_dialback = require "core.s2smanager".verify_dialback;
  25
  26 local st = require "util.stanza";
  27
  28 local log = require "util.logger".init("mod_dialback");
  29
  30 local xmlns_dialback = "jabber:server:dialback";
  31
  32 local dialback_requests = setmetatable({}, { __mode = 'v' });
  33
  34 module:add_handler({"s2sin_unauthed", "s2sin"}, "verify", xmlns_dialback,
  35         function (origin, stanza)
  36                 -- We are being asked to verify the key, to ensure it was generated by us
  37                 log("debug", "verifying dialback key...");
  38                 local attr = stanza.attr;
  39                 -- FIXME: Grr, ejabberd breaks this one too?? it is black and white in XEP-220 example 34
  40                 --if attr.from ~= origin.to_host then error("invalid-from"); end
  41                 local type;
  42                 if s2s_verify_dialback(attr.id, attr.from, attr.to, stanza[1]) then
  43                         type = "valid"
  44                 else
  45                         type = "invalid"
  46                         log("warn", "Asked to verify a dialback key that was incorrect. An imposter is claiming to be %s?", attr.to);
  47                 end
  48                 log("debug", "verified dialback key... it is %s", type);
  49                 origin.sends2s(st.stanza("db:verify", { from = attr.to, to = attr.from, id = attr.id, type = type }):text(stanza[1]));
  50         end);
  51
  52 module:add_handler({ "s2sin_unauthed", "s2sin" }, "result", xmlns_dialback,
  53         function (origin, stanza)
  54                 -- he wants to be identified through dialback
  55                 -- We need to check the key with the Authoritative server
  56                 local attr = stanza.attr;
  57                 origin.hosts[attr.from] = { dialback_key = stanza[1] };
  58
  59                 if not hosts[attr.to] then
  60                         -- Not a host that we serve
  61                         log("info", "%s tried to connect to %s, which we don't serve", attr.from, attr.to);
  62                         origin:close("host-unknown");
  63                         return;
  64                 end
  65
  66                 dialback_requests[attr.from] = origin;
  67
  68                 if not origin.from_host then
  69                         -- Just used for friendlier logging
  70                         origin.from_host = attr.from;
  71                 end
  72                 if not origin.to_host then
  73                         -- Just used for friendlier logging
  74                         origin.to_host = attr.to;
  75                 end
  76
  77                 log("debug", "asking %s if key %s belongs to them", attr.from, stanza[1]);
  78                 send_s2s(attr.to, attr.from,
  79                         st.stanza("db:verify", { from = attr.to, to = attr.from, id = origin.streamid }):text(stanza[1]));
  80         end);
  81
  82 module:add_handler({ "s2sout_unauthed", "s2sout" }, "verify", xmlns_dialback,
  83         function (origin, stanza)
  84                 local attr = stanza.attr;
  85                 local dialback_verifying = dialback_requests[attr.from];
  86                 if dialback_verifying then
  87                         local valid;
  88                         if attr.type == "valid" then
  89                                 s2s_make_authenticated(dialback_verifying, attr.from);
  90                                 valid = "valid";
  91                         else
  92                                 -- Warn the original connection that is was not verified successfully
  93                                 log("warn", "authoritative server for "..(attr.from or "(unknown)").." denied the key");
  94                                 valid = "invalid";
  95                         end
  96                         if not dialback_verifying.sends2s then
  97                                 log("warn", "Incoming s2s session %s was closed in the meantime, so we can't notify it of the db result", tostring(dialback_verifying):match("%w+$"));
  98                         else
  99                                 dialback_verifying.sends2s(
 100                                                 st.stanza("db:result", { from = attr.to, to = attr.from, id = attr.id, type = valid })
 101                                                                 :text(dialback_verifying.hosts[attr.from].dialback_key));
 102                         end
 103                         dialback_requests[attr.from] = nil;
 104                 end
 105         end);
 106
 107 module:add_handler({ "s2sout_unauthed", "s2sout" }, "result", xmlns_dialback,
 108         function (origin, stanza)
 109                 -- Remote server is telling us whether we passed dialback
 110
 111                 local attr = stanza.attr;
 112                 if not hosts[attr.to] then
 113                         origin:close("host-unknown");
 114                         return;
 115                 elseif hosts[attr.to].s2sout[attr.from] ~= origin then
 116                         -- This isn't right
 117                         origin:close("invalid-id");
 118                         return;
 119                 end
 120                 if stanza.attr.type == "valid" then
 121                         s2s_make_authenticated(origin, attr.from);
 122                 else
 123                         -- FIXME: Waiting on #33
 124                         error("dialback failed!");
 125                 end
 126         end);