catarrh/pysim
1
0
Fork 0
mirror of https://gitea.osmocom.org/sim-card/pysim.git synced 2026-03-16 18:38:32 +03:00
Code Issues Packages Projects Releases Wiki Activity

filesystem: do not decode short TransRecEF records

Browse Source 
A TransRecEF is based on a TransparentEF. This means that a TransRecEF
is basically normal TransparentEF that holds a record oriented data
structure. This also requires that the total length of the TransRecEF
is a multiple of the record length of the data structure that is stored
in it. When this is not the case, the last record will be cut short and
the decoding will fail. We should guard against this case.

Related: OS#6598
Change-Id: Ib1dc4d7ce306f1f0b080bb4b6abc36e72431d3fa
This commit is contained in:
Philipp Maier
2025-03-04 12:32:51 +01:00
committed by laforge
parent cabb8edd53
commit 74be2e202f
1 changed files with 12 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

12
pySim/filesystem.py
View File

@@ -1224,6 +1224,13 @@ class TransRecEF(TransparentEF):
Returns: Returns:
abstract_data; dict representing the decoded data abstract_data; dict representing the decoded data
""" """
# The record data length should always be equal or at least greater than the record length defined for the
# TransRecEF. Short records may be occur when the length of the underlying TransparentEF is not a multiple
# of the TransRecEF record length.
if len(raw_hex_data) // 2 < self.__get_rec_len():
return {'raw': raw_hex_data}
method = getattr(self, '_decode_record_hex', None) method = getattr(self, '_decode_record_hex', None)
if callable(method): if callable(method):
return method(raw_hex_data) return method(raw_hex_data)
@@ -1251,6 +1258,11 @@ class TransRecEF(TransparentEF):
Returns: Returns:
abstract_data; dict representing the decoded data abstract_data; dict representing the decoded data
""" """
# See comment in decode_record_hex (above)
if len(raw_bin_data) < self.__get_rec_len():
return {'raw': b2h(raw_bin_data)}
method = getattr(self, '_decode_record_bin', None) method = getattr(self, '_decode_record_bin', None)
if callable(method): if callable(method):
return method(raw_bin_data) return method(raw_bin_data)