construct: add adapter Utf8Adapter to safely interpret utf8 text
Uninitialized Files, File records or fields in a File record or File
usually contain a string of 0xff bytes. This becomes a problem when the
content is normally encoded/decoded as utf8 since by the construct
parser. The parser will throw an expection when it tries to decode the
0xff string as utf8. This is especially a serious problem in pySim-trace
where an execption stops the parser.
Let's fix this by interpreting a string of 0xff as an empty string.
Related: OS#6094
Change-Id: Id114096ccb8b7ff8fcc91e1ef3002526afa09cb7
diff --git a/pySim/ts_31_102.py b/pySim/ts_31_102.py
index 5db3e88..dc674b2 100644
--- a/pySim/ts_31_102.py
+++ b/pySim/ts_31_102.py
@@ -872,7 +872,7 @@
class ePDGId(BER_TLV_IE, tag=0x80, nested=[]):
_construct = Struct('type_of_ePDG_address'/Enum(Byte, FQDN=0, IPv4=1, IPv6=2),
'ePDG_address'/Switch(this.type_of_address,
- {'FQDN': GreedyString("utf8"),
+ {'FQDN': Utf8Adapter(GreedyBytes),
'IPv4': HexAdapter(GreedyBytes),
'IPv6': HexAdapter(GreedyBytes)}))
@@ -951,15 +951,15 @@
class EF_SUPI_NAI(TransparentEF):
class NetworkSpecificIdentifier(TLV_IE, tag=0x80):
# RFC 7542 encoded as UTF-8 string
- _construct = GreedyString("utf8")
+ _construct = Utf8Adapter(GreedyBytes)
class GlobalLineIdentifier(TLV_IE, tag=0x81):
# TS 23.003 clause 28.16.2
- _construct = GreedyString("utf8")
+ _construct = Utf8Adapter(GreedyBytes)
class GlobalCableIdentifier(TLV_IE, tag=0x82):
# TS 23.003 clause 28.15.2
- _construct = GreedyString("utf8")
+ _construct = Utf8Adapter(GreedyBytes)
class NAI_TLV_Collection(TLV_IE_Collection,
nested=[NetworkSpecificIdentifier, GlobalLineIdentifier, GlobalCableIdentifier]):
@@ -984,7 +984,7 @@
# TS 31.102 Section 4.4.11.13
class EF_TN3GPPSNN(TransparentEF):
class ServingNetworkName(BER_TLV_IE, tag=0x80):
- _construct = GreedyString("utf8")
+ _construct = Utf8Adapter(GreedyBytes)
def __init__(self, fid='4f0c', sfid=0x0c, name='EF.TN3GPPSNN',
desc='Trusted non-3GPP Serving network names list', **kwargs):
super().__init__(fid, sfid=sfid, name=name, desc=desc, **kwargs)