+-- sasl.lua v0.4
+-- Copyright (C) 2008-2009 Tobias Markmann
+--
+-- All rights reserved.
+--
+-- Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
+--
+-- * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
+-- * 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.
+-- * 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.
+--
+-- 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.
+
local md5 = require "util.hashes".md5;
local log = require "util.logger".init("sasl");
local tostring = tostring;
local st = require "util.stanza";
local generate_uuid = require "util.uuid".generate;
+local pairs, ipairs = pairs, ipairs;
+local t_insert, t_concat = table.insert, table.concat;
+local to_byte, to_char = string.byte, string.char;
+local to_unicode = require "util.encodings".idna.to_unicode;
local s_match = string.match;
local gmatch = string.gmatch
local string = string
local type = type
local error = error
local print = print
+local setmetatable = setmetatable;
+local assert = assert;
+
+require "util.iterators"
+local keys = keys
+local array = require "util.array"
module "sasl"
-local function new_plain(realm, password_handler)
- local object = { mechanism = "PLAIN", realm = realm, password_handler = password_handler}
- function object.feed(self, message)
-
- if message == "" or message == nil then return "failure", "malformed-request" end
- local response = message
- local authorization = s_match(response, "([^&%z]+)")
- local authentication = s_match(response, "%z([^&%z]+)%z")
- local password = s_match(response, "%z[^&%z]+%z([^&%z]+)")
-
- if authentication == nil or password == nil then return "failure", "malformed-request" end
-
- local password_encoding, correct_password = self.password_handler(authentication, self.realm, "PLAIN")
-
- if correct_password == nil then return "failure", "not-authorized"
- elseif correct_password == false then return "failure", "account-disabled" end
-
- local claimed_password = ""
- if password_encoding == nil then claimed_password = password
- else claimed_password = password_encoding(password) end
-
- self.username = authentication
- if claimed_password == correct_password then
- return "success"
- else
- return "failure", "not-authorized"
- end
+--[[
+Authentication Backend Prototypes:
+
+plain:
+ function(username, realm)
+ return password, state;
end
- return object
-end
-local function new_digest_md5(realm, password_handler)
- --TODO maybe support for authzid
-
- local function serialize(message)
- local data = ""
-
- if type(message) ~= "table" then error("serialize needs an argument of type table.") end
-
- -- testing all possible values
- if message["nonce"] then data = data..[[nonce="]]..message.nonce..[[",]] end
- if message["qop"] then data = data..[[qop="]]..message.qop..[[",]] end
- if message["charset"] then data = data..[[charset=]]..message.charset.."," end
- if message["algorithm"] then data = data..[[algorithm=]]..message.algorithm.."," end
- if message["realm"] then data = data..[[realm="]]..message.realm..[[",]] end
- if message["rspauth"] then data = data..[[rspauth=]]..message.rspauth.."," end
- data = data:gsub(",$", "")
- return data
+plain-test:
+ function(username, realm, password)
+ return true or false, state;
end
-
- local function parse(data)
- message = {}
- for k, v in gmatch(data, [[([%w%-]+)="?([^",]*)"?,?]]) do -- FIXME The hacky regex makes me shudder
- message[k] = v
- end
- return message
+
+digest-md5:
+ function(username, realm, encoding)
+ return digesthash, state;
end
- local object = { mechanism = "DIGEST-MD5", realm = realm, password_handler = password_handler}
-
- --TODO: something better than math.random would be nice, maybe OpenSSL's random number generator
- object.nonce = generate_uuid()
- object.step = 0
- object.nonce_count = {}
-
- function object.feed(self, message)
- self.step = self.step + 1
- if (self.step == 1) then
- local challenge = serialize({ nonce = object.nonce,
- qop = "auth",
- charset = "utf-8",
- algorithm = "md5-sess",
- realm = self.realm});
- return "challenge", challenge
- elseif (self.step == 2) then
- local response = parse(message)
- -- check for replay attack
- if response["nc"] then
- if self.nonce_count[response["nc"]] then return "failure", "not-authorized" end
- end
-
- -- check for username, it's REQUIRED by RFC 2831
- if not response["username"] then
- return "failure", "malformed-request"
- end
- self["username"] = response["username"]
-
- -- check for nonce, ...
- if not response["nonce"] then
- return "failure", "malformed-request"
- else
- -- check if it's the right nonce
- if response["nonce"] ~= tostring(self.nonce) then return "failure", "malformed-request" end
- end
-
- if not response["cnonce"] then return "failure", "malformed-request", "Missing entry for cnonce in SASL message." end
- if not response["qop"] then response["qop"] = "auth" end
-
- if response["realm"] == nil then response["realm"] = "" end
-
- local domain = ""
- local protocol = ""
- if response["digest-uri"] then
- protocol, domain = response["digest-uri"]:match("(%w+)/(.*)$")
- if protocol == nil or domain == nil then return "failure", "malformed-request" end
- else
- return "failure", "malformed-request", "Missing entry for digest-uri in SASL message."
+digest-md5-test:
+ function(username, realm, encoding, digesthash)
+ return true or false, state;
+ end
+]]
+
+local method = {};
+method.__index = method;
+local mechanisms = {};
+local backend_mechanism = {};
+
+-- register a new SASL mechanims
+local function registerMechanism(name, backends, f)
+ assert(type(name) == "string", "Parameter name MUST be a string.");
+ assert(type(backends) == "string" or type(backends) == "table", "Parameter backends MUST be either a string or a table.");
+ assert(type(f) == "function", "Parameter f MUST be a function.");
+ mechanisms[name] = f
+ for _, backend_name in ipairs(backends) do
+ if backend_mechanism[backend_name] == nil then backend_mechanism[backend_name] = {}; end
+ t_insert(backend_mechanism[backend_name], name);
+ end
+end
+
+-- create a new SASL object which can be used to authenticate clients
+function new(realm, profile)
+ sasl_i = {profile = profile};
+ sasl_i.realm = realm;
+ return setmetatable(sasl_i, method);
+end
+
+-- get a list of possible SASL mechanims to use
+function method:mechanisms()
+ local mechanisms = {}
+ for backend, f in pairs(self.profile) do
+ print(backend)
+ if backend_mechanism[backend] then
+ for _, mechanism in ipairs(backend_mechanism[backend]) do
+ mechanisms[mechanism] = true;
end
-
- --TODO maybe realm support
- self.username = response["username"]
- local password_encoding, Y = self.password_handler(response["username"], response["realm"], "DIGEST-MD5")
- if Y == nil then return "failure", "not-authorized"
- elseif Y == false then return "failure", "account-disabled" end
-
- local A1 = Y..":"..response["nonce"]..":"..response["cnonce"]--:authzid
- local A2 = "AUTHENTICATE:"..protocol.."/"..domain
-
- local HA1 = md5(A1, true)
- local HA2 = md5(A2, true)
-
- local KD = HA1..":"..response["nonce"]..":"..response["nc"]..":"..response["cnonce"]..":"..response["qop"]..":"..HA2
- local response_value = md5(KD, true)
-
- if response_value == response["response"] then
- -- calculate rspauth
- A2 = ":"..protocol.."/"..domain
-
- HA1 = md5(A1, true)
- HA2 = md5(A2, true)
-
- KD = HA1..":"..response["nonce"]..":"..response["nc"]..":"..response["cnonce"]..":"..response["qop"]..":"..HA2
- local rspauth = md5(KD, true)
- self.authenticated = true
- return "challenge", serialize({rspauth = rspauth})
- else
- return "failure", "not-authorized", "The response provided by the client doesn't match the one we calculated."
- end
- elseif self.step == 3 then
- if self.authenticated ~= nil then return "success"
- else return "failure", "malformed-request" end
end
end
- return object
+ self["possible_mechanisms"] = mechanisms;
+ return array.collect(keys(mechanisms));
+end
+
+-- select a mechanism to use
+function method:select(mechanism)
+ self.mech_i = mechanisms[mechanism]
+ if self.mech_i == nil then
+ return false;
+ end
+ return true;
+end
+
+-- feed new messages to process into the library
+function method:process(message)
+ if message == "" or message == nil then return "failure", "malformed-request" end
+ return self.mech_i(self, message);
end
-function new(mechanism, realm, password_handler)
- local object
- if mechanism == "PLAIN" then object = new_plain(realm, password_handler)
- elseif mechanism == "DIGEST-MD5" then object = new_digest_md5(realm, password_handler)
+--=========================
+--SASL PLAIN
+local function sasl_mechanism_plain(self, message)
+ local response = message
+ local authorization = s_match(response, "([^%z]+)")
+ local authentication = s_match(response, "%z([^%z]+)%z")
+ local password = s_match(response, "%z[^%z]+%z([^%z]+)")
+
+ if authentication == nil or password == nil then
+ return "failure", "malformed-request";
+ end
+
+ local correct, state = false, false;
+ if self.profile.plain then
+ local correct_password;
+ correct_password, state = self.profile.plain(authentication, self.realm);
+ if correct_password == password then correct = true; else correct = false; end
+ elseif self.profile.plain_test then
+ correct, state = self.profile.plain_test(authentication, self.realm, password);
+ end
+
+ self.username = authentication
+ if not state then
+ return "failure", "account-disabled";
+ end
+
+ if correct then
+ return "success";
else
- log("debug", "Unsupported SASL mechanism: "..tostring(mechanism));
- return nil
+ return "failure", "not-authorized";
end
- return object
end
+registerMechanism("PLAIN", {"plain", "plain_test"}, sasl_mechanism_plain);
-return _M;
\ No newline at end of file
+return _M;
projects / prosody.git / blobdiff