| # Generic code related to Secure Channel processing |
| # |
| # (C) 2023-2024 by Harald Welte <laforge@osmocom.org> |
| # |
| # This program is free software: you can redistribute it and/or modify |
| # it under the terms of the GNU General Public License as published by |
| # the Free Software Foundation, either version 2 of the License, or |
| # (at your option) any later version. |
| # |
| # This program is distributed in the hope that it will be useful, |
| # but WITHOUT ANY WARRANTY; without even the implied warranty of |
| # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| # GNU General Public License for more details. |
| # |
| # You should have received a copy of the GNU General Public License |
| # along with this program. If not, see <http://www.gnu.org/licenses/>. |
| |
| import abc |
| from pySim.utils import b2h, h2b, ResTuple, Hexstr |
| |
| class SecureChannel(abc.ABC): |
| @abc.abstractmethod |
| def wrap_cmd_apdu(self, apdu: bytes) -> bytes: |
| """Wrap Command APDU according to specific Secure Channel Protocol.""" |
| pass |
| |
| @abc.abstractmethod |
| def unwrap_rsp_apdu(self, sw: bytes, rsp_apdu: bytes) -> bytes: |
| """UnWrap Response-APDU according to specific Secure Channel Protocol.""" |
| pass |
| |
| def send_apdu_wrapper(self, send_fn: callable, pdu: Hexstr, *args, **kwargs) -> ResTuple: |
| """Wrapper function to wrap command APDU and unwrap repsonse APDU around send_apdu callable.""" |
| pdu_wrapped = b2h(self.wrap_cmd_apdu(h2b(pdu))) |
| res, sw = send_fn(pdu_wrapped, *args, **kwargs) |
| res_unwrapped = b2h(self.unwrap_rsp_apdu(h2b(sw), h2b(res))) |
| return res_unwrapped, sw |