IPB 4中的密码哈希

Question

I am using IPB 4 forum platform for my community and I want to make a portal that uses the forums user/password combo The problem is that I cant figure out how to hash the password when logging in

I've tried this

function ipbhash($salt, $password){
    return crypt($password, '$2a$13$' . $salt);
}

function ipbhash($salt, $password){
    return  md5(md5($salt) . md5($password));
}

But still no luck