Files
pysim-local/pySim/apdu_source/pyshark_gsmtap.py
Philipp Maier 162ba3af3e pySim-trace: mark card reset in the trace
The trace log currently does not contain any information about card
resets. This makes the trace difficult to follow. Let's use the
CardReset object to display the ATR in the trace.

Related: OS#6094
Change-Id: Ia550a8bd2f45d2ad622cb2ac2a2905397db76bce
2023-07-28 10:14:19 +02:00

91 lines
3.3 KiB
Python

# coding=utf-8
# (C) 2022 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 sys
import logging
from pprint import pprint as pp
from typing import Tuple
import pyshark
from pySim.utils import h2b, b2h
from pySim.apdu import Tpdu
from pySim.gsmtap import GsmtapMessage
from . import ApduSource, PacketType, CardReset
from pySim.apdu.ts_102_221 import ApduCommands as UiccApduCommands
from pySim.apdu.ts_31_102 import ApduCommands as UsimApduCommands
from pySim.apdu.global_platform import ApduCommands as GpApduCommands
ApduCommands = UiccApduCommands + UsimApduCommands + GpApduCommands
logger = logging.getLogger(__name__)
class _PysharkGsmtap(ApduSource):
"""APDU Source [provider] base class for reading GSMTAP SIM APDU via tshark."""
def __init__(self, pyshark_inst):
self.pyshark = pyshark_inst
self.bank_id = None
self.bank_slot = None
self.cmd_tpdu = None
super().__init__()
def read_packet(self) -> PacketType:
p = self.pyshark.next()
return self._parse_packet(p)
def _set_or_verify_bank_slot(self, bsl: Tuple[int, int]):
"""Keep track of the bank:slot to make sure we don't mix traces of multiple cards"""
if not self.bank_id:
self.bank_id = bsl[0]
self.bank_slot = bsl[1]
else:
if self.bank_id != bsl[0] or self.bank_slot != bsl[1]:
raise ValueError('Received data for unexpected B(%u:%u)' % (bsl[0], bsl[1]))
def _parse_packet(self, p) -> PacketType:
udp_layer = p['udp']
udp_payload_hex = udp_layer.get_field('payload').replace(':','')
gsmtap = GsmtapMessage(h2b(udp_payload_hex))
gsmtap_msg = gsmtap.decode()
if gsmtap_msg['type'] != 'sim':
raise ValueError('Unsupported GSMTAP type %s' % gsmtap_msg['type'])
sub_type = gsmtap_msg['sub_type']
if sub_type == 'apdu':
return ApduCommands.parse_cmd_bytes(gsmtap_msg['body'])
elif sub_type == 'atr':
# card has been reset
return CardReset(gsmtap_msg['body'])
elif sub_type in ['pps_req', 'pps_rsp']:
# simply ignore for now
pass
else:
raise ValueError('Unsupported GSMTAP-SIM sub-type %s' % sub_type)
class PysharkGsmtapPcap(_PysharkGsmtap):
"""APDU Source [provider] class for reading GSMTAP from a PCAP
file via pyshark, which in turn uses tshark (part of wireshark).
"""
def __init__(self, pcap_filename):
"""
Args:
pcap_filename: File name of the pcap file to be opened
"""
pyshark_inst = pyshark.FileCapture(pcap_filename, display_filter='gsm_sim', use_json=True, keep_packets=False)
super().__init__(pyshark_inst)