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 st = require "util.stanza";
18 local set = require "util.set";
19 local array = require "util.array";
20 local to_unicode = require "util.encodings".idna.to_unicode;
22 local tostring = tostring;
23 local pairs, ipairs = pairs, ipairs;
24 local t_insert, t_concat = table.insert, table.concat;
25 local s_match = string.match;
28 local setmetatable = setmetatable;
29 local assert = assert;
30 local require = require;
32 require "util.iterators"
35 local array = require "util.array"
39 Authentication Backend Prototypes:
41 state = false : disabled
42 state = true : enabled
43 state = nil : non-existant
46 function(username, realm)
47 return password, state;
51 function(username, realm, password)
52 return true or false, state;
56 function(username, domain, realm, encoding) -- domain and realm are usually the same; for some broken
57 -- implementations it's not
58 return digesthash, state;
62 function(username, domain, realm, encoding, digesthash)
63 return true or false, state;
68 method.__index = method;
69 local mechanisms = {};
70 local backend_mechanism = {};
72 -- register a new SASL mechanims
73 local function registerMechanism(name, backends, f)
74 assert(type(name) == "string", "Parameter name MUST be a string.");
75 assert(type(backends) == "string" or type(backends) == "table", "Parameter backends MUST be either a string or a table.");
76 assert(type(f) == "function", "Parameter f MUST be a function.");
78 for _, backend_name in ipairs(backends) do
79 if backend_mechanism[backend_name] == nil then backend_mechanism[backend_name] = {}; end
80 t_insert(backend_mechanism[backend_name], name);
84 -- create a new SASL object which can be used to authenticate clients
85 function new(realm, profile, forbidden)
86 local sasl_i = {profile = profile};
88 local s = setmetatable(sasl_i, method);
89 if forbidden == nil then forbidden = {} end
90 s:forbidden(forbidden)
94 -- get a fresh clone with the same realm, profiles and forbidden mechanisms
95 function method:clean_clone()
96 return new(self.realm, self.profile, self:forbidden())
99 -- set the forbidden mechanisms
100 function method:forbidden( restrict )
103 self.restrict = set.new(restrict);
106 return array.collect(self.restrict:items());
110 -- get a list of possible SASL mechanims to use
111 function method:mechanisms()
112 local mechanisms = {}
113 for backend, f in pairs(self.profile) do
114 if backend_mechanism[backend] then
115 for _, mechanism in ipairs(backend_mechanism[backend]) do
116 if not self.restrict:contains(mechanism) then
117 mechanisms[mechanism] = true;
122 self["possible_mechanisms"] = mechanisms;
123 return array.collect(keys(mechanisms));
126 -- select a mechanism to use
127 function method:select(mechanism)
132 self.mech_i = mechanisms[mechanism]
133 if self.mech_i == nil then
139 -- feed new messages to process into the library
140 function method:process(message)
141 --if message == "" or message == nil then return "failure", "malformed-request" end
142 return self.mech_i(self, message);
145 -- load the mechanisms
146 local load_mechs = {"plain", "digest-md5", "anonymous", "scram"}
147 for _, mech in ipairs(load_mechs) do
148 local name = "util.sasl."..mech;
149 local m = require(name);
150 m.init(registerMechanism)