2 -- Copyright (C) 2008-2009 Tobias Markmann
4 -- All rights reserved.
6 -- Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
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.
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.
15 local md5 = require "util.hashes".md5;
16 local log = require "util.logger".init("sasl");
17 local tostring = tostring;
18 local st = require "util.stanza";
19 local generate_uuid = require "util.uuid".generate;
20 local pairs, ipairs = pairs, ipairs;
21 local t_insert, t_concat = table.insert, table.concat;
22 local to_byte, to_char = string.byte, string.char;
23 local to_unicode = require "util.encodings".idna.to_unicode;
24 local s_match = string.match;
25 local gmatch = string.gmatch
27 local math = require "math"
31 local setmetatable = setmetatable;
32 local assert = assert;
34 require "util.iterators"
37 local array = require "util.array"
41 Authentication Backend Prototypes:
44 function(username, realm)
45 return password, state;
49 function(username, realm, password)
50 return true or false, state;
54 function(username, realm, encoding)
55 return digesthash, state;
59 function(username, realm, encoding, digesthash)
60 return true or false, state;
65 method.__index = method;
66 local mechanisms = {};
67 local backend_mechanism = {};
69 -- register a new SASL mechanims
70 local function registerMechanism(name, backends, f)
71 assert(type(name) == "string", "Parameter name MUST be a string.");
72 assert(type(backends) == "string" or type(backends) == "table", "Parameter backends MUST be either a string or a table.");
73 assert(type(f) == "function", "Parameter f MUST be a function.");
75 for _, backend_name in ipairs(backends) do
76 if backend_mechanism[backend_name] == nil then backend_mechanism[backend_name] = {}; end
77 t_insert(backend_mechanism[backend_name], name);
81 -- create a new SASL object which can be used to authenticate clients
82 function new(realm, profile)
83 sasl_i = {profile = profile};
84 return setmetatable(sasl_i, method);
87 -- get a list of possible SASL mechanims to use
88 function method:mechanisms()
90 for backend, f in pairs(self.profile) do
92 if backend_mechanism[backend] then
93 for _, mechanism in ipairs(backend_mechanism[backend]) do
94 mechanisms[mechanism] = true;
98 self["possible_mechanisms"] = mechanisms;
99 return array.collect(keys(mechanisms));
102 -- select a mechanism to use
103 function method:select(mechanism)
104 self.mech_i = mechanisms[mechanism]
105 if self.mech_i == nil then return false; end
109 -- feed new messages to process into the library
110 function method:process(message)
111 if message == "" or message == nil then return "failure", "malformed-request" end
112 return self.mech_i(self, message);
115 --=========================
117 local function sasl_mechanism_plain(self, message)
118 local response = message
119 local authorization = s_match(response, "([^&%z]+)")
120 local authentication = s_match(response, "%z([^&%z]+)%z")
121 local password = s_match(response, "%z[^&%z]+%z([^&%z]+)")
123 if authentication == nil or password == nil then return "failure", "malformed-request" end
125 local correct, state = false, false, false;
126 if self.profile.plain then
127 local correct_password, state = self.profile.plain(authentication, self.realm);
128 if correct_password == password then correct = true; else correct = false; end
129 else if self.profile.plain_test then
130 correct, state = self.profile.plain_test(authentication, self.realm, password);
133 self.username = authentication
135 return "failure", "account-disabled";
141 return "failure", "not-authorized";
144 registerMechanism("PLAIN", {"plain", "plain_test"}, sasl_mechanism_plain);