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 s2s_make_authenticated = require "core.s2smanager".make_authenticated;
15 local base64 = require "util.encodings".base64;
17 local cert_verify_identity = require "util.x509".verify_identity;
19 local nodeprep = require "util.encodings".stringprep.nodeprep;
20 local usermanager_get_sasl_handler = require "core.usermanager".get_sasl_handler;
21 local tostring = tostring;
23 local secure_auth_only = module:get_option("c2s_require_encryption") or module:get_option("require_encryption");
24 local allow_unencrypted_plain_auth = module:get_option("allow_unencrypted_plain_auth")
26 local log = module._log;
28 local xmlns_sasl ='urn:ietf:params:xml:ns:xmpp-sasl';
29 local xmlns_bind ='urn:ietf:params:xml:ns:xmpp-bind';
30 local xmlns_stanzas ='urn:ietf:params:xml:ns:xmpp-stanzas';
32 local function build_reply(status, ret, err_msg)
33 local reply = st.stanza(status, {xmlns = xmlns_sasl});
34 if status == "challenge" then
35 --log("debug", "CHALLENGE: %s", ret or "");
36 reply:text(base64.encode(ret or ""));
37 elseif status == "failure" then
39 if err_msg then reply:tag("text"):text(err_msg); end
40 elseif status == "success" then
41 --log("debug", "SUCCESS: %s", ret or "");
42 reply:text(base64.encode(ret or ""));
44 module:log("error", "Unknown sasl status: %s", status);
49 local function handle_status(session, status, ret, err_msg)
50 if status == "failure" then
51 session.sasl_handler = session.sasl_handler:clean_clone();
52 elseif status == "success" then
53 local username = nodeprep(session.sasl_handler.username);
55 local ok, err = sm_make_authenticated(session, session.sasl_handler.username);
57 session.sasl_handler = nil;
58 session:reset_stream();
60 module:log("warn", "SASL succeeded but username was invalid");
61 session.sasl_handler = session.sasl_handler:clean_clone();
62 return "failure", "not-authorized", "User authenticated successfully, but username was invalid";
65 return status, ret, err_msg;
68 local function sasl_process_cdata(session, stanza)
69 local text = stanza[1];
71 text = base64.decode(text);
72 --log("debug", "AUTH: %s", text:gsub("[%z\001-\008\011\012\014-\031]", " "));
74 session.sasl_handler = nil;
75 session.send(build_reply("failure", "incorrect-encoding"));
79 local status, ret, err_msg = session.sasl_handler:process(text);
80 status, ret, err_msg = handle_status(session, status, ret, err_msg);
81 local s = build_reply(status, ret, err_msg);
82 log("debug", "sasl reply: %s", tostring(s));
87 module:hook_stanza(xmlns_sasl, "success", function (session, stanza)
88 if session.type ~= "s2sout_unauthed" or session.external_auth ~= "attempting" then return; end
89 module:log("debug", "SASL EXTERNAL with %s succeeded", session.to_host);
90 session.external_auth = "succeeded"
91 session:reset_stream();
93 local default_stream_attr = {xmlns = "jabber:server", ["xmlns:stream"] = "http://etherx.jabber.org/streams",
94 ["xmlns:db"] = 'jabber:server:dialback', version = "1.0", to = session.to_host, from = session.from_host};
95 session.sends2s("<?xml version='1.0'?>");
96 session.sends2s(st.stanza("stream:stream", default_stream_attr):top_tag());
98 s2s_make_authenticated(session, session.to_host);
102 module:hook_stanza(xmlns_sasl, "failure", function (session, stanza)
103 if session.type ~= "s2sout_unauthed" or session.external_auth ~= "attempting" then return; end
105 module:log("info", "SASL EXTERNAL with %s failed", session.to_host)
106 -- TODO: Log the failure reason
107 session.external_auth = "failed"
110 module:hook_stanza(xmlns_sasl, "failure", function (session, stanza)
111 -- TODO: Dialback wasn't loaded. Do something useful.
114 module:hook_stanza("http://etherx.jabber.org/streams", "features", function (session, stanza)
115 if session.type ~= "s2sout_unauthed" or not session.secure then return; end
117 local mechanisms = stanza:get_child("mechanisms", xmlns_sasl)
119 for mech in mechanisms:childtags() do
120 if mech[1] == "EXTERNAL" then
121 module:log("debug", "Initiating SASL EXTERNAL with %s", session.to_host);
122 local reply = st.stanza("auth", {xmlns = xmlns_sasl, mechanism = "EXTERNAL"});
123 reply:text(base64.encode(session.from_host))
124 session.sends2s(reply)
125 session.external_auth = "attempting"
132 local function s2s_external_auth(session, stanza)
133 local mechanism = stanza.attr.mechanism;
135 if not session.secure then
136 if mechanism == "EXTERNAL" then
137 session.sends2s(build_reply("failure", "encryption-required"))
139 session.sends2s(build_reply("failure", "invalid-mechanism"))
144 if mechanism ~= "EXTERNAL" or session.cert_chain_status ~= "valid" then
145 session.sends2s(build_reply("failure", "invalid-mechanism"))
149 local text = stanza[1]
151 session.sends2s(build_reply("failure", "malformed-request"))
155 -- Either the value is "=" and we've already verified the external
156 -- cert identity, or the value is a string and either matches the
159 text = base64.decode(text)
161 session.sends2s(build_reply("failure", "incorrect-encoding"))
165 if session.cert_identity_status == "valid" then
166 if text ~= "" and text ~= session.from_host then
167 session.sends2s(build_reply("failure", "invalid-authzid"))
172 session.sends2s(build_reply("failure", "invalid-authzid"))
176 local cert = session.conn:socket():getpeercertificate()
177 if (cert_verify_identity(text, "xmpp-server", cert)) then
178 session.cert_identity_status = "valid"
180 session.cert_identity_status = "invalid"
181 session.sends2s(build_reply("failure", "invalid-authzid"))
186 session.external_auth = "succeeded"
188 if not session.from_host then
189 session.from_host = text;
191 session.sends2s(build_reply("success"))
192 module:log("info", "Accepting SASL EXTERNAL identity from %s", text or session.from_host);
193 s2s_make_authenticated(session, text or session.from_host)
194 session:reset_stream();
198 module:hook("stanza/urn:ietf:params:xml:ns:xmpp-sasl:auth", function(event)
199 local session, stanza = event.origin, event.stanza;
200 if session.type == "s2sin_unauthed" then
201 return s2s_external_auth(session, stanza)
204 if session.type ~= "c2s_unauthed" then return; end
206 if session.sasl_handler and session.sasl_handler.selected then
207 session.sasl_handler = nil; -- allow starting a new SASL negotiation before completing an old one
209 if not session.sasl_handler then
210 session.sasl_handler = usermanager_get_sasl_handler(module.host);
212 local mechanism = stanza.attr.mechanism;
213 if not session.secure and (secure_auth_only or (mechanism == "PLAIN" and not allow_unencrypted_plain_auth)) then
214 session.send(build_reply("failure", "encryption-required"));
217 local valid_mechanism = session.sasl_handler:select(mechanism);
218 if not valid_mechanism then
219 session.send(build_reply("failure", "invalid-mechanism"));
222 return sasl_process_cdata(session, stanza);
224 module:hook("stanza/urn:ietf:params:xml:ns:xmpp-sasl:response", function(event)
225 local session = event.origin;
226 if not(session.sasl_handler and session.sasl_handler.selected) then
227 session.send(build_reply("failure", "not-authorized", "Out of order SASL element"));
230 return sasl_process_cdata(session, event.stanza);
232 module:hook("stanza/urn:ietf:params:xml:ns:xmpp-sasl:abort", function(event)
233 local session = event.origin;
234 session.sasl_handler = nil;
235 session.send(build_reply("failure", "aborted"));
239 local mechanisms_attr = { xmlns='urn:ietf:params:xml:ns:xmpp-sasl' };
240 local bind_attr = { xmlns='urn:ietf:params:xml:ns:xmpp-bind' };
241 local xmpp_session_attr = { xmlns='urn:ietf:params:xml:ns:xmpp-session' };
242 module:hook("stream-features", function(event)
243 local origin, features = event.origin, event.features;
244 if not origin.username then
245 if secure_auth_only and not origin.secure then
248 origin.sasl_handler = usermanager_get_sasl_handler(module.host);
249 features:tag("mechanisms", mechanisms_attr);
250 for mechanism in pairs(origin.sasl_handler:mechanisms()) do
251 if mechanism ~= "PLAIN" or origin.secure or allow_unencrypted_plain_auth then
252 features:tag("mechanism"):text(mechanism):up();
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 if chain is valid and either we didn't validate
266 -- the identity or it passed.
267 if origin.cert_chain_status == "valid" and origin.cert_identity_status ~= "invalid" then --TODO: Configurable
268 module:log("debug", "Offering SASL EXTERNAL")
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:child_with_name("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);