UB authentication schema

Actually this is modified DIGEST schema with SHA256 hash algorithm and modified authorization mechanism. In case of this schema usage UnityBase store client passwords hash in upasswordHashHexa attribute of uba_user entity. Schema is protected from MIT type of attack and secure enough for most type of application.

On the UI client enter a userName & password, after this client must send a two request:

1) Request a nonce

Client call auth endpoint passing userName as parameter.

-> GET|POST appName/auth?AUTHTYPE=UB&userName=admin

Server return a serverNonce - one time public key valid for 5 minutes in a result field

<- 200 OK
{"result":"c0a94994a9baaf5f6f071a13c6b5f7c4f8219e1ba514d9f0b81df57cc4b4b81f"}

2) Sending hashed password and obtain a sessionWord

Client generate clientNonce, calculate hash of his password and call auth again, passing as parameters userName, clientNonce and password hashed with nonces.

-> GET|POST appName/auth?AUTHTYPE=UB&
  clientNonce=ffac6401331cce72e82ecfa8dd40c8cb4456098000392da2bac8c41d19b57467&
  password=09561d07211a8ef1d125355bfb5e871028826484a30bde6c98562742d2e9460e
  &userName=admin

here:

clientNonce = unique string client generate and memorize
secretWord = sha256('salt' + passwordWhatUserEnterDuringLogin)
password=sha256(appName + serverNonce + clientNonce + userName + secretWord)

Server return sessionPrivateKey, used in future request as one of signature part.

<- 200 OK
{
    "result":"537445910+634e82b0aa70c0ec67395d59935f1cec36c14cedc4cc824049e175109987d1c6",
    "logonname":"admin",
    "uData": {}
}

result in response is a sessionPrivateKey. First part of result before + is clientSessionID.

Consider what neither password, nor password hash not transferred other the wire, so the MIT attack is impossible.

JavaScript implementation:

var secretWord, sessionPrivateKey, hexa8ID;
promise = me.get('auth', {
    params: {
        AUTHTYPE: authSchema,
        userName: authParams.login
    }
}).then(function(resp){
    var
        serverNonce = resp.data.result,
        SHA256 = CryptoJS.SHA256;
    if (!serverNonce) throw new Error('invalid auth response');
    var clientNonce = SHA256(new Date().toISOString().substr(0, 16)).toString();
    var pwdHash = SHA256('salt' + authParams.password).toString();
    secretWord = pwdHash;
    return me.get('auth', {
        params: {
            AUTHTYPE: authSchema,
            userName: authParams.login,
            password: SHA256(appName.toLowerCase() + serverNonce +
                clientNonce + authParams.login + pwdHash).toString(),
            clientNonce: clientNonce
        }
    });
}).then(function(response){
    sessionPrivateKey = response.result;
    hexa8ID = hexa8(sessionWord.split('+')[0]);
});