krb5_s4u_userid
encode_krb5_s4u_userid(const krb5_s4u_userid *, krb5_data **);
krb5_s4u_userid user_id;
krb5_free_s4u_userid_contents(krb5_context, krb5_s4u_userid *);
krb5_s4u_userid *id;
DEFFIELD(s4u_userid_0, krb5_s4u_userid, nonce, 0, int32);
DEFFIELD(s4u_userid_1, krb5_s4u_userid, user, 1, opt_s4u_principal);
DEFFIELD(s4u_userid_2, krb5_s4u_userid, user, 2, realm_of_principal);
DEFFIELD(s4u_userid_3, krb5_s4u_userid, subject_cert, 3, opt_ostring_data);
DEFFIELD(s4u_userid_4, krb5_s4u_userid, options, 4, opt_krb5_flags);
DEFSEQTYPE(s4u_userid, krb5_s4u_userid, s4u_userid_fields);
krb5_free_s4u_userid_contents(krb5_context context, krb5_s4u_userid *user_id)
krb5_s4u_userid *userid,