krb5_derive_Kc
int krb5_derive_Kc(const struct krb5_enctype *krb5, const struct krb5_buffer *TK,
ret = krb5_derive_Kc(krb5, TK, usage, setkey, gfp);
ret = krb5_derive_Kc(krb5, base_key, test->use, &result, GFP_KERNEL);