diff options
Diffstat (limited to 'util')
| -rw-r--r-- | util/sasl.lua | 145 |
1 files changed, 143 insertions, 2 deletions
diff --git a/util/sasl.lua b/util/sasl.lua index dbd6326a..f2ff6592 100644 --- a/util/sasl.lua +++ b/util/sasl.lua @@ -1,16 +1,24 @@ local base64 = require "base64" +local md5 = require "md5" +local crypto = require "crypto" local log = require "util.logger".init("sasl"); local tostring = tostring; local st = require "util.stanza"; +local generate_uuid = require "util.uuid".generate; local s_match = string.match; -module "sasl" +local gmatch = string.gmatch +local math = require "math" +local type = type +local error = error +local print = print +module "sasl" local function new_plain(onAuth, onSuccess, onFail, onWrite) local object = { mechanism = "PLAIN", onAuth = onAuth, onSuccess = onSuccess, onFail = onFail, onWrite = onWrite} - --local challenge = base64.encode(""); + local challenge = base64.encode(""); --onWrite(st.stanza("challenge", {xmlns = "urn:ietf:params:xml:ns:xmpp-sasl"}):text(challenge)) object.feed = function(self, stanza) if stanza.name ~= "response" and stanza.name ~= "auth" then self.onFail("invalid-stanza-tag") end @@ -30,9 +38,142 @@ local function new_plain(onAuth, onSuccess, onFail, onWrite) end +--[[ +SERVER: +nonce="3145176401",qop="auth",charset=utf-8,algorithm=md5-sess + +CLIENT: username="tobiasfar",nonce="3145176401",cnonce="pJiW7hzeZLvOSAf7gBzwTzLWe4obYOVDlnNESzQCzGg=",nc=00000001,digest-uri="xmpp/jabber.org",qop=auth,response=99a93ba75235136e6403c3a2ba37089d,charset=utf-8 + +username="tobias",nonce="4406697386",cnonce="wUnT7vYrOB0V8D/lKd5bhpaNCk+hLJwc8T4CBCqp7WM=",nc=00000001,digest-uri="xmpp/luaetta.ath.cx",qop=auth,response=d202b8a1bdf8204816fb23c5f87b6b63,charset=utf-8 + +SERVER: +rspauth=ab66d28c260e97da577ce3aac46a8991 +]]-- +local function new_digest_md5(onAuth, onSuccess, onFail, onWrite) + local function H(s) + return md5.sum(s) + end + + local function KD(k, s) + return H(k..":"..s) + end + + local function HEX(n) + return md5.sumhexa(n) + end + + local function HMAC(k, s) + return crypto.hmac.digest("md5", s, k, true) + end + + 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["rspauth"] then data = data..[[rspauth=]]..message.algorith.."," end + data = data:gsub(",$", "") + return data + end + + local function parse(data) + message = {} + for k, v in gmatch(data, [[([%w%-]+)="?([%w%-%/%.]+)"?,?]]) do + message[k] = v + end + return message + end + + local object = { mechanism = "DIGEST-MD5", onAuth = onAuth, onSuccess = onSuccess, onFail = onFail, + onWrite = onWrite } + + --TODO: something better than math.random would be nice, maybe OpenSSL's random number generator + object.nonce = math.random(0, 9) + for i = 1, 9 do object.nonce = object.nonce..math.random(0, 9) end + object.step = 1 + object.nonce_count = {} + local challenge = base64.encode(serialize({ nonce = object.nonce, + qop = "auth", + charset = "utf-8", + algorithm = "md5-sess"} )); + object.onWrite(st.stanza("challenge", {xmlns = "urn:ietf:params:xml:ns:xmpp-sasl"}):text(challenge)) + object.feed = function(self, stanza) + if stanza.name ~= "response" and stanza.name ~= "auth" then self.onFail("invalid-stanza-tag") end + if stanza.attr.xmlns ~= "urn:ietf:params:xml:ns:xmpp-sasl" then self.onFail("invalid-stanza-namespace") end + if stanza.name == "auth" then return end + self.step = self.step + 1 + if (self.step == 2) then + local response = parse(base64.decode(stanza[1])) + -- check for replay attack + if response["nonce-count"] then + if self.nonce_count[response["nonce-count"]] then self.onFail("not-authorized") end + end + + -- check for username, it's REQUIRED by RFC 2831 + if not response["username"] then + self.onFail("malformed-request") + end + + -- check for nonce, ... + if not response["nonce"] then + self.onFail("malformed-request") + else + -- check if it's the right nonce + if response["nonce"] ~= self.nonce then self.onFail("malformed-request") end + end + + if not response["cnonce"] then self.onFail("malformed-request") end + if not response["qop"] then response["qop"] = "auth" end + + local hostname = "" + local protocol = "" + if response["digest-uri"] then + protocol, hostname = response["digest-uri"]:match("(%w+)/(.*)$") + else + error("No digest-uri") + end + + -- compare response_value with own calculation + --local A1 = usermanager.get_md5(response["username"], hostname)..":"..response["nonce"]..response["cnonce"] + local A1 = H("tobias:luaetta.ath.cx:tobias")..":"..response["nonce"]..response["cnonce"] + local A2 = "AUTHENTICATE:"..response["digest-uri"] + + local response_value = HEX(KD(HEX(H(A1)), response["nonce"]..":"..response["nonce-count"]..":"..response["cnonce-value"]..":"..response["qop"]..":"..HEX(H(A2)))) + + log("debug", "response_value: "..response_value); + + if response["qop"] == "auth" then + + else + + end + + --local response_value = HEX(KD(HEX(H(A1)), response["nonce"]..":"..response["nonce-count"]..":"..response["cnonce-value"]..":"..response["qop"]..":"..HEX(H(A2)))) + + end + --[[ + local authorization = s_match(response, "([^&%z]+)") + local authentication = s_match(response, "%z([^&%z]+)%z") + local password = s_match(response, "%z[^&%z]+%z([^&%z]+)") + if self.onAuth(authentication, password) == true then + self.onWrite(st.stanza("success", {xmlns = "urn:ietf:params:xml:ns:xmpp-sasl"})) + self.onSuccess(authentication) + else + self.onWrite(st.stanza("failure", {xmlns = "urn:ietf:params:xml:ns:xmpp-sasl"}):tag("temporary-auth-failure")); + end]]-- + end + return object +end + function new(mechanism, onAuth, onSuccess, onFail, onWrite) local object if mechanism == "PLAIN" then object = new_plain(onAuth, onSuccess, onFail, onWrite) + elseif mechanism == "DIGEST-MD5" then object = new_digest_md5(onAuth, onSuccess, onFail, onWrite) else log("debug", "Unsupported SASL mechanism: "..tostring(mechanism)); onFail("unsupported-mechanism") |