--- a/util/sasl.lua Sun Nov 16 02:10:01 2008 +0500
+++ b/util/sasl.lua Sat Nov 15 22:30:09 2008 +0100
@@ -1,7 +1,5 @@
-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";
@@ -27,7 +25,7 @@
local authentication = s_match(response, "%z([^&%z]+)%z")
local password = s_match(response, "%z[^&%z]+%z([^&%z]+)")
- local password_encoding, correct_password = self.password_handler(authentication.."@"..self.realm, "PLAIN")
+ local password_encoding, correct_password = self.password_handler(authentication, self.realm, "PLAIN")
local claimed_password = ""
if password_encoding == nil then claimed_password = password
@@ -36,7 +34,7 @@
self.username = authentication
if claimed_password == correct_password then
log("debug", "success")
- return "success", nil
+ return "success"
else
log("debug", "failure")
return "failure", "not-authorized"
@@ -45,7 +43,7 @@
return object
end
-local function new_digest_md5(onAuth, onSuccess, onFail, onWrite)
+local function new_digest_md5(realm, password_handler)
--TODO maybe support for authzid
local function serialize(message)
@@ -74,107 +72,97 @@
return message
end
- local object = { mechanism = "DIGEST-MD5", onAuth = onAuth, onSuccess = onSuccess, onFail = onFail,
- onWrite = onWrite }
+ 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()
- log("debug", "SASL nonce: "..object.nonce)
- object.step = 1
+ object.step = 0
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)
- log("debug", "SASL step: "..self.step)
- 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["nc"] then
- if self.nonce_count[response["nc"]] 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
- self["username"] = response["username"]
-
- -- check for nonce, ...
- if not response["nonce"] then
- self.onFail("malformed-request")
- else
- -- check if it's the right nonce
- if response["nonce"] ~= tostring(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
-
- if response["realm"] == nil then response["realm"] = "" end
-
- local domain = ""
- local protocol = ""
- if response["digest-uri"] then
- protocol, domain = 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"]
-
- --FIXME actual username and password here :P
- local X = "tobias:"..response["realm"]..":tobias"
- local Y = md5.sum(X)
- local A1 = Y..":"..response["nonce"]..":"..response["cnonce"]--:authzid
- local A2 = "AUTHENTICATE:"..protocol.."/"..domain
-
- local HA1 = md5.sumhexa(A1)
- local HA2 = md5.sumhexa(A2)
-
- local KD = HA1..":"..response["nonce"]..":"..response["nc"]..":"..response["cnonce"]..":"..response["qop"]..":"..HA2
- local response_value = md5.sumhexa(KD)
-
- log("debug", "response_value: "..response_value);
- log("debug", "response: "..response["response"]);
- if response_value == response["response"] then
- -- calculate rspauth
- A2 = ":"..protocol.."/"..domain
-
- HA1 = md5.sumhexa(A1)
- HA2 = md5.sumhexa(A2)
-
- KD = HA1..":"..response["nonce"]..":"..response["nc"]..":"..response["cnonce"]..":"..response["qop"]..":"..HA2
- local rspauth = md5.sumhexa(KD)
-
- self.onWrite(st.stanza("challenge", {xmlns = "urn:ietf:params:xml:ns:xmpp-sasl"}):text(base64.encode(serialize({rspauth = rspauth}))))
- else
- self.onWrite(st.stanza("response", {xmlns = "urn:ietf:params:xml:ns:xmpp-sasl"}))
- self.onFail()
- end
- elseif self.step == 3 then
- if stanza.name == "response" then
- self.onWrite(st.stanza("success", {xmlns = "urn:ietf:params:xml:ns:xmpp-sasl"}))
- self.onSuccess(self.username)
- else
- self.onFail("Third step isn't a response stanza.")
- end
- end
- end
+
+ function object.feed(self, message)
+ log("debug", "SASL step: "..self.step)
+ 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});
+ log("debug", "challenge: "..challenge)
+ 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" 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+)/(.*)$")
+ else
+ return "failure", "malformed-request", "Missing entry for digest-uri in SASL message."
+ end
+
+ --TODO maybe realm support
+ self.username = response["username"]
+ local password_encoding, Y = self.password_handler(response["username"], response["realm"], "DIGEST-MD5")
+ local A1 = Y..":"..response["nonce"]..":"..response["cnonce"]--:authzid
+ local A2 = "AUTHENTICATE:"..protocol.."/"..domain
+
+ local HA1 = md5.sumhexa(A1)
+ local HA2 = md5.sumhexa(A2)
+
+ local KD = HA1..":"..response["nonce"]..":"..response["nc"]..":"..response["cnonce"]..":"..response["qop"]..":"..HA2
+ local response_value = md5.sumhexa(KD)
+
+ log("debug", "response_value: "..response_value);
+ log("debug", "response: "..response["response"]);
+ if response_value == response["response"] then
+ -- calculate rspauth
+ A2 = ":"..protocol.."/"..domain
+
+ HA1 = md5.sumhexa(A1)
+ HA2 = md5.sumhexa(A2)
+
+ KD = HA1..":"..response["nonce"]..":"..response["nc"]..":"..response["cnonce"]..":"..response["qop"]..":"..HA2
+ local rspauth = md5.sumhexa(KD)
+
+ 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
+ return "success"
+ end
+ end
return object
end
-function new(mechanism, realm, password)
+function new(mechanism, realm, password_handler)
local object
- if mechanism == "PLAIN" then object = new_plain(realm, password)
- --elseif mechanism == "DIGEST-MD5" then object = new_digest_md5(ream, password)
+ if mechanism == "PLAIN" then object = new_plain(realm, password_handler)
+ elseif mechanism == "DIGEST-MD5" then object = new_digest_md5(realm, password_handler)
else
log("debug", "Unsupported SASL mechanism: "..tostring(mechanism));
return nil