2 -- Copyright (C) 2008-2010 Matthew Wild
3 -- Copyright (C) 2008-2010 Waqas Hussain
5 -- This project is MIT/X11 licensed. Please see the
6 -- COPYING file in the source package for more information.
11 local st = require "util.stanza";
12 local sm_bind_resource = require "core.sessionmanager".bind_resource;
13 local sm_make_authenticated = require "core.sessionmanager".make_authenticated;
14 local base64 = require "util.encodings".base64;
16 local usermanager_get_sasl_handler = require "core.usermanager".get_sasl_handler;
17 local tostring = tostring;
19 local secure_auth_only = module:get_option_boolean("c2s_require_encryption", module:get_option_boolean("require_encryption", false));
20 local allow_unencrypted_plain_auth = module:get_option_boolean("allow_unencrypted_plain_auth", false)
21 local insecure_mechanisms = module:get_option_set("insecure_sasl_mechanisms", allow_unencrypted_plain_auth and {} or {"PLAIN", "LOGIN"});
22 local disabled_mechanisms = module:get_option_set("disable_sasl_mechanisms", { "DIGEST-MD5" });
24 local log = module._log;
26 local xmlns_sasl ='urn:ietf:params:xml:ns:xmpp-sasl';
27 local xmlns_bind ='urn:ietf:params:xml:ns:xmpp-bind';
29 local function build_reply(status, ret, err_msg)
30 local reply = st.stanza(status, {xmlns = xmlns_sasl});
31 if status == "failure" then
33 if err_msg then reply:tag("text"):text(err_msg); end
34 elseif status == "challenge" or status == "success" then
38 reply:text(base64.encode(ret));
41 module:log("error", "Unknown sasl status: %s", status);
46 local function handle_status(session, status, ret, err_msg)
47 if status == "failure" then
48 module:fire_event("authentication-failure", { session = session, condition = ret, text = err_msg });
49 session.sasl_handler = session.sasl_handler:clean_clone();
50 elseif status == "success" then
51 local ok, err = sm_make_authenticated(session, session.sasl_handler.username);
53 module:fire_event("authentication-success", { session = session });
54 session.sasl_handler = nil;
55 session:reset_stream();
57 module:log("warn", "SASL succeeded but username was invalid");
58 module:fire_event("authentication-failure", { session = session, condition = "not-authorized", text = err });
59 session.sasl_handler = session.sasl_handler:clean_clone();
60 return "failure", "not-authorized", "User authenticated successfully, but username was invalid";
63 return status, ret, err_msg;
66 local function sasl_process_cdata(session, stanza)
67 local text = stanza[1];
69 text = base64.decode(text);
70 --log("debug", "AUTH: %s", text:gsub("[%z\001-\008\011\012\014-\031]", " "));
72 session.sasl_handler = nil;
73 session.send(build_reply("failure", "incorrect-encoding"));
77 local status, ret, err_msg = session.sasl_handler:process(text);
78 status, ret, err_msg = handle_status(session, status, ret, err_msg);
79 local s = build_reply(status, ret, err_msg);
80 log("debug", "sasl reply: %s", tostring(s));
85 module:hook_stanza(xmlns_sasl, "success", function (session, stanza)
86 if session.type ~= "s2sout_unauthed" or session.external_auth ~= "attempting" then return; end
87 module:log("debug", "SASL EXTERNAL with %s succeeded", session.to_host);
88 session.external_auth = "succeeded"
89 session:reset_stream();
90 session:open_stream(session.from_host, session.to_host);
92 module:fire_event("s2s-authenticated", { session = session, host = session.to_host });
96 module:hook_stanza(xmlns_sasl, "failure", function (session, stanza)
97 if session.type ~= "s2sout_unauthed" or session.external_auth ~= "attempting" then return; end
99 module:log("info", "SASL EXTERNAL with %s failed", session.to_host)
100 -- TODO: Log the failure reason
101 session.external_auth = "failed"
106 module:hook_stanza("http://etherx.jabber.org/streams", "features", function (session, stanza)
107 if session.type ~= "s2sout_unauthed" or not session.secure then return; end
109 local mechanisms = stanza:get_child("mechanisms", xmlns_sasl)
111 for mech in mechanisms:childtags() do
112 if mech[1] == "EXTERNAL" then
113 module:log("debug", "Initiating SASL EXTERNAL with %s", session.to_host);
114 local reply = st.stanza("auth", {xmlns = xmlns_sasl, mechanism = "EXTERNAL"});
115 reply:text(base64.encode(session.from_host))
116 session.sends2s(reply)
117 session.external_auth = "attempting"
124 local function s2s_external_auth(session, stanza)
125 if session.external_auth ~= "offered" then return end -- Unexpected request
127 local mechanism = stanza.attr.mechanism;
129 if mechanism ~= "EXTERNAL" then
130 session.sends2s(build_reply("failure", "invalid-mechanism"));
134 if not session.secure then
135 session.sends2s(build_reply("failure", "encryption-required"));
139 local text = stanza[1];
141 session.sends2s(build_reply("failure", "malformed-request"));
145 text = base64.decode(text);
147 session.sends2s(build_reply("failure", "incorrect-encoding"));
151 -- The text value is either "" or equals session.from_host
152 if not ( text == "" or text == session.from_host ) then
153 session.sends2s(build_reply("failure", "invalid-authzid"));
157 -- We've already verified the external cert identity before offering EXTERNAL
158 if session.cert_chain_status ~= "valid" or session.cert_identity_status ~= "valid" then
159 session.sends2s(build_reply("failure", "not-authorized"));
165 session.external_auth = "succeeded";
166 session.sends2s(build_reply("success"));
167 module:log("info", "Accepting SASL EXTERNAL identity from %s", session.from_host);
168 module:fire_event("s2s-authenticated", { session = session, host = session.from_host });
169 session:reset_stream();
173 module:hook("stanza/urn:ietf:params:xml:ns:xmpp-sasl:auth", function(event)
174 local session, stanza = event.origin, event.stanza;
175 if session.type == "s2sin_unauthed" then
176 return s2s_external_auth(session, stanza)
179 if session.type ~= "c2s_unauthed" or module:get_host_type() ~= "local" then return; end
181 if session.sasl_handler and session.sasl_handler.selected then
182 session.sasl_handler = nil; -- allow starting a new SASL negotiation before completing an old one
184 if not session.sasl_handler then
185 session.sasl_handler = usermanager_get_sasl_handler(module.host, session);
187 local mechanism = stanza.attr.mechanism;
188 if not session.secure and (secure_auth_only or insecure_mechanisms:contains(mechanism)) then
189 session.send(build_reply("failure", "encryption-required"));
191 elseif disabled_mechanisms:contains(mechanism) then
192 session.send(build_reply("failure", "invalid-mechanism"));
195 local valid_mechanism = session.sasl_handler:select(mechanism);
196 if not valid_mechanism then
197 session.send(build_reply("failure", "invalid-mechanism"));
200 return sasl_process_cdata(session, stanza);
202 module:hook("stanza/urn:ietf:params:xml:ns:xmpp-sasl:response", function(event)
203 local session = event.origin;
204 if not(session.sasl_handler and session.sasl_handler.selected) then
205 session.send(build_reply("failure", "not-authorized", "Out of order SASL element"));
208 return sasl_process_cdata(session, event.stanza);
210 module:hook("stanza/urn:ietf:params:xml:ns:xmpp-sasl:abort", function(event)
211 local session = event.origin;
212 session.sasl_handler = nil;
213 session.send(build_reply("failure", "aborted"));
217 local function tls_unique(self)
218 return self.userdata["tls-unique"]:getpeerfinished();
221 local mechanisms_attr = { xmlns='urn:ietf:params:xml:ns:xmpp-sasl' };
222 local bind_attr = { xmlns='urn:ietf:params:xml:ns:xmpp-bind' };
223 local xmpp_session_attr = { xmlns='urn:ietf:params:xml:ns:xmpp-session' };
224 module:hook("stream-features", function(event)
225 local origin, features = event.origin, event.features;
226 if not origin.username then
227 if secure_auth_only and not origin.secure then
230 local sasl_handler = usermanager_get_sasl_handler(module.host, origin)
231 origin.sasl_handler = sasl_handler;
232 if origin.encrypted then
233 -- check wether LuaSec has the nifty binding to the function needed for tls-unique
234 -- FIXME: would be nice to have this check only once and not for every socket
235 if sasl_handler.add_cb_handler then
236 local socket = origin.conn:socket();
237 if socket.getpeerfinished then
238 sasl_handler:add_cb_handler("tls-unique", tls_unique);
240 sasl_handler["userdata"] = {
241 ["tls-unique"] = socket;
245 local mechanisms = st.stanza("mechanisms", mechanisms_attr);
246 for mechanism in pairs(sasl_handler:mechanisms()) do
247 if (not disabled_mechanisms:contains(mechanism)) and (origin.secure or not insecure_mechanisms:contains(mechanism)) then
248 mechanisms:tag("mechanism"):text(mechanism):up();
251 if mechanisms[1] then
252 features:add_child(mechanisms);
254 (origin.log or log)("warn", "No SASL mechanisms to offer");
257 features:tag("bind", bind_attr):tag("required"):up():up();
258 features:tag("session", xmpp_session_attr):tag("optional"):up():up();
262 module:hook("s2s-stream-features", function(event)
263 local origin, features = event.origin, event.features;
264 if origin.secure and origin.type == "s2sin_unauthed" then
265 -- Offer EXTERNAL only if both chain and identity is valid.
266 if origin.cert_chain_status == "valid" and origin.cert_identity_status == "valid" then
267 module:log("debug", "Offering SASL EXTERNAL");
268 origin.external_auth = "offered"
269 features:tag("mechanisms", { xmlns = xmlns_sasl })
270 :tag("mechanism"):text("EXTERNAL")
276 module:hook("iq/self/urn:ietf:params:xml:ns:xmpp-bind:bind", function(event)
277 local origin, stanza = event.origin, event.stanza;
279 if stanza.attr.type == "set" then
280 local bind = stanza.tags[1];
281 resource = bind:get_child("resource");
282 resource = resource and #resource.tags == 0 and resource[1] or nil;
284 local success, err_type, err, err_msg = sm_bind_resource(origin, resource);
286 origin.send(st.reply(stanza)
287 :tag("bind", { xmlns = xmlns_bind })
288 :tag("jid"):text(origin.full_jid));
289 origin.log("debug", "Resource bound: %s", origin.full_jid);
291 origin.send(st.error_reply(stanza, err_type, err, err_msg));
292 origin.log("debug", "Resource bind failed: %s", err_msg or err);
297 local function handle_legacy_session(event)
298 event.origin.send(st.reply(event.stanza));
302 module:hook("iq/self/urn:ietf:params:xml:ns:xmpp-session:session", handle_legacy_session);
303 module:hook("iq/host/urn:ietf:params:xml:ns:xmpp-session:session", handle_legacy_session);