kem-pbkdf2 {
    {field . {map}}
    {field a {str} =pbkdf2}
    {field cek {bin} >0} {# wrapped CEK}
    {field hash {str} >0} {# hash algorithm identifier}
    {field iter {int} >0} {# number of iterations}
    {field salt {bin} >0}
    {field wrap {str} >0} {# key wrapping algorithm identifier}
}
