plugins/mod_saslauth.lua

   1
   2 local st = require "util.stanza";
   3 local send = require "core.sessionmanager".send_to_session;
   4 local sm_bind_resource = require "core.sessionmanager".bind_resource;
   5 local jid
   6
   7 local usermanager_validate_credentials = require "core.usermanager".validate_credentials;
   8 local t_concat, t_insert = table.concat, table.insert;
   9 local tostring = tostring;
  10
  11 local log = require "util.logger".init("mod_saslauth");
  12
  13 local xmlns_sasl ='urn:ietf:params:xml:ns:xmpp-sasl';
  14 local xmlns_bind ='urn:ietf:params:xml:ns:xmpp-bind';
  15 local xmlns_stanzas ='urn:ietf:params:xml:ns:xmpp-stanzas';
  16
  17 local new_sasl = require "util.sasl".new;
  18
  19 local function build_reply(status, ret)
  20         local reply = st.stanza(status, {xmlns = xmlns_sasl});
  21         if status == "challenge" then
  22                 reply:text(ret or "");
  23         elseif status == "failure" then
  24                 reply:tag(ret):up();
  25         elseif status == "success" then
  26                 reply:text(ret or "");
  27         else
  28                 error("Unknown sasl status: "..status);
  29         end
  30         return reply;
  31 end
  32
  33 local function handle_status(session, status)
  34         if status == "failure" then
  35                 session.sasl_handler = nil;
  36         elseif status == "success" then
  37                 session.sasl_handler = nil;
  38                 session:reset_stream();
  39         end
  40 end
  41
  42 local function password_callback(jid, mechanism)
  43         local node, host = jid_split(jid);
  44         local password = (datamanager.load(node, host, "accounts") or {}).password; -- FIXME handle hashed passwords
  45         local func = function(x) return x; end;
  46         if password then
  47                 if mechanism == "PLAIN" then
  48                         return func, password;
  49                 elseif mechanism == "DIGEST-MD5" then
  50                         return func, require "hashes".md5(node.."::"..password);
  51                 end
  52         end
  53         return func, nil;
  54 end
  55
  56 add_handler("c2s_unauthed", "auth", xmlns_sasl,
  57                 function (session, stanza)
  58                         if not session.sasl_handler then
  59                                 session.sasl_handler = new_sasl(stanza.attr.mechanism, session.host, password_callback);
  60                                 local status, ret = session.sasl_handler:feed(stanza[1]);
  61                                 handle_status(session, status);
  62                                 session.send(build_reply(status, ret));
  63                                 --[[session.sasl_handler = new_sasl(stanza.attr.mechanism,
  64                                         function (username, password)
  65                                                 -- onAuth
  66                                                 require "core.usermanager"
  67                                                 if usermanager_validate_credentials(session.host, username, password) then
  68                                                         return true;
  69                                                 end
  70                                                 return false;
  71                                         end,
  72                                         function (username)
  73                                                 -- onSuccess
  74                                                 local success, err = sessionmanager.make_authenticated(session, username);
  75                                                 if not success then
  76                                                         sessionmanager.destroy_session(session);
  77                                                         return;
  78                                                 end
  79                                                 session.sasl_handler = nil;
  80                                                 session:reset_stream();
  81                                         end,
  82                                         function (reason)
  83                                                 -- onFail
  84                                                 log("debug", "SASL failure, reason: %s", reason);
  85                                         end,
  86                                         function (stanza)
  87                                                 -- onWrite
  88                                                 log("debug", "SASL writes: %s", tostring(stanza));
  89                                                 send(session, stanza);
  90                                         end
  91                                 );
  92                                 session.sasl_handler:feed(stanza);      ]]
  93                         else
  94                                 error("Client tried to negotiate SASL again", 0);
  95                         end
  96                 end);
  97
  98 add_handler("c2s_unauthed", "abort", xmlns_sasl,
  99         function(session, stanza)
 100                 if not session.sasl_handler then error("Attempt to abort when sasl has not started"); end
 101                 local status, ret = session.sasl_handler:feed(stanza[1]);
 102                 handle_status(session, status);
 103                 session.send(build_reply(status, ret));
 104         end);
 105
 106 add_handler("c2s_unauthed", "response", xmlns_sasl,
 107         function(session, stanza)
 108                 if not session.sasl_handler then error("Attempt to respond when sasl has not started"); end
 109                 local status, ret = session.sasl_handler:feed(stanza[1]);
 110                 handle_status(session, status);
 111                 session.send(build_reply(status, ret));
 112         end);
 113
 114 add_event_hook("stream-features",
 115                                         function (session, features)
 116                                                 if not session.username then
 117                                                         t_insert(features, "<mechanisms xmlns='urn:ietf:params:xml:ns:xmpp-sasl'>");
 118                                                                 t_insert(features, "<mechanism>PLAIN</mechanism>");
 119                                                                 t_insert(features, "<mechanism>DIGEST-MD5</mechanism>");
 120                                                         t_insert(features, "</mechanisms>");
 121                                                 else
 122                                                         t_insert(features, "<bind xmlns='urn:ietf:params:xml:ns:xmpp-bind'><required/></bind>");
 123                                                         t_insert(features, "<session xmlns='urn:ietf:params:xml:ns:xmpp-session'/>");
 124                                                 end
 125                                                 --send [[<register xmlns="http://jabber.org/features/iq-register"/> ]]
 126                                         end);
 127
 128 add_iq_handler("c2s", "urn:ietf:params:xml:ns:xmpp-bind",
 129                 function (session, stanza)
 130                         log("debug", "Client tried to bind to a resource");
 131                         local resource;
 132                         if stanza.attr.type == "set" then
 133                                 local bind = stanza.tags[1];
 134
 135                                 if bind and bind.attr.xmlns == xmlns_bind then
 136                                         resource = bind:child_with_name("resource");
 137                                         if resource then
 138                                                 resource = resource[1];
 139                                         end
 140                                 end
 141                         end
 142                         local success, err = sm_bind_resource(session, resource);
 143                         if not success then
 144                                 local reply = st.reply(stanza);
 145                                 reply.attr.type = "error";
 146                                 if err == "conflict" then
 147                                         reply:tag("error", { type = "modify" })
 148                                                 :tag("conflict", { xmlns = xmlns_stanzas });
 149                                 elseif err == "constraint" then
 150                                         reply:tag("error", { type = "cancel" })
 151                                                 :tag("resource-constraint", { xmlns = xmlns_stanzas });
 152                                 elseif err == "auth" then
 153                                         reply:tag("error", { type = "cancel" })
 154                                                 :tag("not-allowed", { xmlns = xmlns_stanzas });
 155                                 end
 156                                 send(session, reply);
 157                         else
 158                                 local reply = st.reply(stanza);
 159                                 reply:tag("bind", { xmlns = xmlns_bind})
 160                                         :tag("jid"):text(session.full_jid);
 161                                 send(session, reply);
 162                         end
 163                 end);
 164
 165 add_iq_handler("c2s", "urn:ietf:params:xml:ns:xmpp-session",
 166                 function (session, stanza)
 167                         log("debug", "Client tried to bind to a resource");
 168                         send(session, st.reply(stanza));
 169                 end);