-local base64 = require "base64"
-local md5 = require "md5"
-local crypto = require "crypto"
+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 s_match = string.match;
local gmatch = string.gmatch
+local string = string
local math = require "math"
local type = type
local error = error
local print = print
+local idna_ascii = require "util.encodings".idna.to_ascii
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("");
- --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
- local response = base64.decode(stanza[1])
- 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
+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
+ end
return object
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 new_digest_md5(realm, password_handler)
+ --TODO maybe support for authzid
local function serialize(message)
local data = ""
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
+ 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
end
local function parse(data)
message = {}
- for k, v in gmatch(data, [[([%w%-]+)="?([%w%-%/%.]+)"?,?]]) do
+ for k, v in gmatch(data, [[([%w%-]+)="?([^",]*)"?,?]]) do -- FIXME The hacky regex makes me shudder
message[k] = v
end
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 = math.random(0, 9)
- for i = 1, 9 do object.nonce = object.nonce..math.random(0, 9) end
- object.step = 1
+ object.nonce = generate_uuid()
+ 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)
- 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-- = H(response["username"]..":"..realm-value, ":", passwd } ),
- -- ":", nonce-value, ":", cnonce-value)
- local A2
-
- --local response_value = HEX(KD(HEX(H(A1)), response["nonce"]..":"..response["nonce-count"]..":"..response["cnonce-value"]..":"..response["qop"]..":"..HEX(H(A2))))
-
- 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
+
+ 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."
+ 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.."/"..idna_ascii(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.."/"..idna_ascii(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
end
-function new(mechanism, onAuth, onSuccess, onFail, onWrite)
+function new(mechanism, realm, password_handler)
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)
+ 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));
- onFail("unsupported-mechanism")
+ return nil
end
return object
end
projects / prosody.git / blobdiff