def encode_bit_str(self, obj):
if isinstance(obj._val, ASN1.ASN1Obj):
# obj._val: ASN1Obj, according to CONTAINING constraint
V = Layer('V')
V.append(Int('pad_len', Pt=0, Type='uint8'))
obj._val._encode()
V.extend(obj._val._msg)
obj._val._msg = None
#
else:
# obj._val: (BE uint value, BE uint bit length)
val_len = obj._val[1] // 8
val_ext = obj._val[1] % 8
if val_ext:
val_len += 1
V = Layer('V')
V.append(Int('pad_len', Pt=(8-val_ext)%8, Type='uint8'))
V.append(Bit('val', Pt=obj._val[0], BitLen=obj._val[1],
Repr=self._REPR_BIT_STR))
if val_ext > 0:
V.append(Bit('pad', Pt=0, BitLen=8-val_ext,
Repr=self._REPR_BIT_STR))
#
obj._msg = BER_TLV(obj.get_name())
obj._msg.set(V)
self.handle_tag_enc(obj)
def encode_bit_str(self, obj):
if isinstance(obj._val, ASN1.ASN1Obj):
# obj._val: ASN1Obj, according to CONTAINING constraint
V = Layer('V')
V.append(Int('pad_len', Pt=0, Type='uint8'))
obj._val._encode()
V.extend(obj._val._msg)
obj._val._msg = None
#
else:
# obj._val: (BE uint value, BE uint bit length)
val_len = obj._val[1] // 8
val_ext = obj._val[1] % 8
if val_ext:
val_len += 1
V = Layer('V')
V.append(Int('pad_len', Pt=(8 - val_ext) % 8, Type='uint8'))
V.append(
Bit('val',
Pt=obj._val[0],
BitLen=obj._val[1],
Repr=self._REPR_BIT_STR))
if val_ext > 0:
V.append(
Bit('pad',
Pt=0,
BitLen=8 - val_ext,
Repr=self._REPR_BIT_STR))
#
obj._msg = BER_TLV(obj.get_name())
obj._msg.set(V)
self.handle_tag_enc(obj)
def parse(self, buf=''):
self.__init__(self.CallName)
self.map(buf)
L = len(self)
#
# parse nested BER_TLV structures within the Value
if self[0].PC():
# indefinite form
indef = self[1]() == -1
# parsing further internal Value
buf = str(self[2])
inner = []
marker = None
while buf:
tlv = BER_TLV()
tlv.parse(buf)
buf = buf[len(tlv):]
if indef and (tlv[0]() == 0 and tlv[1]() == 0):
marker = tlv
marker.CallName = '_end_'
break
else:
inner.append(tlv)
if inner:
self.remove(self[2])
V = Layer('V')
V.extend(inner)
self.append(V)
if marker:
self.append(marker)
# returns the length parsed
return L
def parse(self, buf=''):
self.__init__(self.CallName)
self.map(buf)
L = len(self)
#
# parse nested BER_TLV structures within the Value
if self[0].PC():
# indefinite form
indef = self[1]() == -1
# parsing further internal Value
buf = str(self[2])
inner = []
marker = None
while buf:
tlv = BER_TLV()
tlv.parse(buf)
buf = buf[len(tlv):]
if indef and (tlv[0]() == 0 and tlv[1]() == 0):
marker = tlv
marker.CallName = '_end_'
break
else:
inner.append(tlv)
if inner:
self.remove(self[2])
V = Layer('V')
V.extend(inner)
self.append(V)
if marker:
self.append(marker)
# returns the length parsed
return L
