1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
|
-- Prosody IM
-- Copyright (C) 2008-2010 Matthew Wild
-- Copyright (C) 2008-2010 Waqas Hussain
--
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--
local st = require "util.stanza";
local sm_bind_resource = require "core.sessionmanager".bind_resource;
local sm_make_authenticated = require "core.sessionmanager".make_authenticated;
local base64 = require "util.encodings".base64;
local nodeprep = require "util.encodings".stringprep.nodeprep;
local usermanager_get_sasl_handler = require "core.usermanager".get_sasl_handler;
local t_concat, t_insert = table.concat, table.insert;
local tostring = tostring;
local secure_auth_only = module:get_option("c2s_require_encryption") or module:get_option("require_encryption");
local anonymous_login = module:get_option("anonymous_login");
local allow_unencrypted_plain_auth = module:get_option("allow_unencrypted_plain_auth")
local log = module._log;
local xmlns_sasl ='urn:ietf:params:xml:ns:xmpp-sasl';
local xmlns_bind ='urn:ietf:params:xml:ns:xmpp-bind';
local xmlns_stanzas ='urn:ietf:params:xml:ns:xmpp-stanzas';
local new_sasl = require "util.sasl".new;
local anonymous_authentication_profile = {
anonymous = function(username, realm)
return true; -- for normal usage you should always return true here
end
};
local function build_reply(status, ret, err_msg)
local reply = st.stanza(status, {xmlns = xmlns_sasl});
if status == "challenge" then
--log("debug", "CHALLENGE: %s", ret or "");
reply:text(base64.encode(ret or ""));
elseif status == "failure" then
reply:tag(ret):up();
if err_msg then reply:tag("text"):text(err_msg); end
elseif status == "success" then
--log("debug", "SUCCESS: %s", ret or "");
reply:text(base64.encode(ret or ""));
else
module:log("error", "Unknown sasl status: %s", status);
end
return reply;
end
local function handle_status(session, status, ret, err_msg)
if status == "failure" then
session.sasl_handler = session.sasl_handler:clean_clone();
elseif status == "success" then
local username = nodeprep(session.sasl_handler.username);
local ok, err = sm_make_authenticated(session, session.sasl_handler.username);
if ok then
session.sasl_handler = nil;
session:reset_stream();
else
module:log("warn", "SASL succeeded but username was invalid");
session.sasl_handler = session.sasl_handler:clean_clone();
return "failure", "not-authorized", "User authenticated successfully, but username was invalid";
end
end
return status, ret, err_msg;
end
local function sasl_handler(session, stanza)
if stanza.name == "auth" then
-- FIXME ignoring duplicates because ejabberd does
local mechanism = stanza.attr.mechanism;
if anonymous_login then
if mechanism ~= "ANONYMOUS" then
return session.send(build_reply("failure", "invalid-mechanism"));
end
elseif mechanism == "ANONYMOUS" then
return session.send(build_reply("failure", "mechanism-too-weak"));
end
if not session.secure and (secure_auth_only or (mechanism == "PLAIN" and not allow_unencrypted_plain_auth)) then
return session.send(build_reply("failure", "encryption-required"));
end
local valid_mechanism = session.sasl_handler:select(mechanism);
if not valid_mechanism then
return session.send(build_reply("failure", "invalid-mechanism"));
end
elseif not session.sasl_handler then
return; -- FIXME ignoring out of order stanzas because ejabberd does
end
local text = stanza[1];
if text then
text = base64.decode(text);
--log("debug", "AUTH: %s", text:gsub("[%z\001-\008\011\012\014-\031]", " "));
if not text then
session.sasl_handler = nil;
session.send(build_reply("failure", "incorrect-encoding"));
return;
end
end
local status, ret, err_msg = session.sasl_handler:process(text);
status, ret, err_msg = handle_status(session, status, ret, err_msg);
local s = build_reply(status, ret, err_msg);
log("debug", "sasl reply: %s", tostring(s));
session.send(s);
end
module:add_handler("c2s_unauthed", "auth", xmlns_sasl, sasl_handler);
module:add_handler("c2s_unauthed", "abort", xmlns_sasl, sasl_handler);
module:add_handler("c2s_unauthed", "response", xmlns_sasl, sasl_handler);
local mechanisms_attr = { xmlns='urn:ietf:params:xml:ns:xmpp-sasl' };
local bind_attr = { xmlns='urn:ietf:params:xml:ns:xmpp-bind' };
local xmpp_session_attr = { xmlns='urn:ietf:params:xml:ns:xmpp-session' };
module:hook("stream-features", function(event)
local origin, features = event.origin, event.features;
if not origin.username then
if secure_auth_only and not origin.secure then
return;
end
if anonymous_login then
origin.sasl_handler = new_sasl(module.host, anonymous_authentication_profile);
else
origin.sasl_handler = usermanager_get_sasl_handler(module.host);
end
features:tag("mechanisms", mechanisms_attr);
for mechanism in pairs(origin.sasl_handler:mechanisms()) do
if mechanism ~= "PLAIN" or origin.secure or allow_unencrypted_plain_auth then
features:tag("mechanism"):text(mechanism):up();
end
end
features:up();
else
features:tag("bind", bind_attr):tag("required"):up():up();
features:tag("session", xmpp_session_attr):tag("optional"):up():up();
end
end);
module:hook("iq/self/urn:ietf:params:xml:ns:xmpp-bind:bind", function(event)
log("debug", "Client requesting a resource bind");
local origin, stanza = event.origin, event.stanza;
local resource;
if stanza.attr.type == "set" then
local bind = stanza.tags[1];
resource = bind:child_with_name("resource");
resource = resource and #resource.tags == 0 and resource[1] or nil;
end
local success, err_type, err, err_msg = sm_bind_resource(origin, resource);
if success then
origin.send(st.reply(stanza)
:tag("bind", { xmlns = xmlns_bind })
:tag("jid"):text(origin.full_jid));
else
origin.send(st.error_reply(stanza, err_type, err, err_msg));
end
return true;
end);
module:hook("iq/self/urn:ietf:params:xml:ns:xmpp-session:session", function(event)
log("debug", "Client requesting a session");
event.origin.send(st.reply(event.stanza));
return true;
end);
|