krb5int_etm_decrypt
krb5_error_code krb5int_etm_decrypt(const struct krb5_keytypes *ktp,
krb5int_aes2_crypto_length, krb5int_etm_encrypt, krb5int_etm_decrypt,
krb5int_aes2_crypto_length, krb5int_etm_encrypt, krb5int_etm_decrypt,