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mod_auth_cyrus/sasl_cyrus.lua @ 4710:099dcdb732b1

mod_auth_cyrus: Import from Prosody rev 8f1e7fd55e7b
author Kim Alvefur <zash@zash.se>
date Sun, 17 Oct 2021 17:08:07 +0200
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equal deleted inserted replaced
4709:679f1834dbdb 4710:099dcdb732b1
1 -- sasl.lua v0.4
2 -- Copyright (C) 2008-2009 Tobias Markmann
3 --
4 -- All rights reserved.
5 --
6 -- Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
7 --
8 -- * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
9 -- * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
10 -- * Neither the name of Tobias Markmann nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
11 --
12 -- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
13
14 local cyrussasl = require "cyrussasl";
15 local log = require "util.logger".init("sasl_cyrus");
16
17 local setmetatable = setmetatable
18
19 local pcall = pcall
20 local s_match, s_gmatch = string.match, string.gmatch
21
22 local sasl_errstring = {
23 -- SASL result codes --
24 [1] = "another step is needed in authentication";
25 [0] = "successful result";
26 [-1] = "generic failure";
27 [-2] = "memory shortage failure";
28 [-3] = "overflowed buffer";
29 [-4] = "mechanism not supported";
30 [-5] = "bad protocol / cancel";
31 [-6] = "can't request info until later in exchange";
32 [-7] = "invalid parameter supplied";
33 [-8] = "transient failure (e.g., weak key)";
34 [-9] = "integrity check failed";
35 [-12] = "SASL library not initialized";
36
37 -- client only codes --
38 [2] = "needs user interaction";
39 [-10] = "server failed mutual authentication step";
40 [-11] = "mechanism doesn't support requested feature";
41
42 -- server only codes --
43 [-13] = "authentication failure";
44 [-14] = "authorization failure";
45 [-15] = "mechanism too weak for this user";
46 [-16] = "encryption needed to use mechanism";
47 [-17] = "One time use of a plaintext password will enable requested mechanism for user";
48 [-18] = "passphrase expired, has to be reset";
49 [-19] = "account disabled";
50 [-20] = "user not found";
51 [-23] = "version mismatch with plug-in";
52 [-24] = "remote authentication server unavailable";
53 [-26] = "user exists, but no verifier for user";
54
55 -- codes for password setting --
56 [-21] = "passphrase locked";
57 [-22] = "requested change was not needed";
58 [-27] = "passphrase is too weak for security policy";
59 [-28] = "user supplied passwords not permitted";
60 };
61 setmetatable(sasl_errstring, { __index = function() return "undefined error!" end });
62
63 local _ENV = nil;
64 -- luacheck: std none
65
66 local method = {};
67 method.__index = method;
68 local initialized = false;
69
70 local function init(service_name)
71 if not initialized then
72 local st, errmsg = pcall(cyrussasl.server_init, service_name);
73 if st then
74 initialized = true;
75 else
76 log("error", "Failed to initialize Cyrus SASL: %s", errmsg);
77 end
78 end
79 end
80
81 -- create a new SASL object which can be used to authenticate clients
82 -- host_fqdn may be nil in which case gethostname() gives the value.
83 -- For GSSAPI, this determines the hostname in the service ticket (after
84 -- reverse DNS canonicalization, only if [libdefaults] rdns = true which
85 -- is the default).
86 local function new(realm, service_name, app_name, host_fqdn)
87
88 init(app_name or service_name);
89
90 local st, ret = pcall(cyrussasl.server_new, service_name, host_fqdn, realm, nil, nil)
91 if not st then
92 log("error", "Creating SASL server connection failed: %s", ret);
93 return nil;
94 end
95
96 local sasl_i = { realm = realm, service_name = service_name, cyrus = ret };
97
98 if cyrussasl.set_canon_cb then
99 local c14n_cb = function (user)
100 local node = s_match(user, "^([^@]+)");
101 log("debug", "Canonicalizing username %s to %s", user, node)
102 return node
103 end
104 cyrussasl.set_canon_cb(sasl_i.cyrus, c14n_cb);
105 end
106
107 cyrussasl.setssf(sasl_i.cyrus, 0, 0xffffffff)
108 local mechanisms = {};
109 local cyrus_mechs = cyrussasl.listmech(sasl_i.cyrus, nil, "", " ", "");
110 for w in s_gmatch(cyrus_mechs, "[^ ]+") do
111 mechanisms[w] = true;
112 end
113 sasl_i.mechs = mechanisms;
114 return setmetatable(sasl_i, method);
115 end
116
117 -- get a fresh clone with the same realm and service name
118 function method:clean_clone()
119 return new(self.realm, self.service_name)
120 end
121
122 -- get a list of possible SASL mechanims to use
123 function method:mechanisms()
124 return self.mechs;
125 end
126
127 -- select a mechanism to use
128 function method:select(mechanism)
129 if not self.selected and self.mechs[mechanism] then
130 self.selected = mechanism;
131 return true;
132 end
133 end
134
135 -- feed new messages to process into the library
136 function method:process(message)
137 local err;
138 local data;
139
140 if not self.first_step_done then
141 err, data = cyrussasl.server_start(self.cyrus, self.selected, message or "")
142 self.first_step_done = true;
143 else
144 err, data = cyrussasl.server_step(self.cyrus, message or "")
145 end
146
147 self.username = cyrussasl.get_username(self.cyrus)
148
149 if (err == 0) then -- SASL_OK
150 if self.require_provisioning and not self.require_provisioning(self.username) then
151 return "failure", "not-authorized", "User authenticated successfully, but not provisioned for XMPP";
152 end
153 return "success", data
154 elseif (err == 1) then -- SASL_CONTINUE
155 return "challenge", data
156 elseif (err == -4) then -- SASL_NOMECH
157 log("debug", "SASL mechanism not available from remote end")
158 return "failure", "invalid-mechanism", "SASL mechanism not available"
159 elseif (err == -13) then -- SASL_BADAUTH
160 return "failure", "not-authorized", sasl_errstring[err];
161 else
162 log("debug", "Got SASL error condition %d: %s", err, sasl_errstring[err]);
163 return "failure", "undefined-condition", sasl_errstring[err];
164 end
165 end
166
167 return {
168 new = new;
169 };