TagClassPrivate: "PRIVATE ",
TagClassUniversal: "UNIV ",
}
+EOC = b"\x00\x00"
+EOC_LEN = len(EOC)
########################################################################
pass
+class LenIndefiniteForm(DecodeError):
+ pass
+
+
class TagMismatch(DecodeError):
pass
if octets_num + 1 > len(data):
raise NotEnoughData("encoded length is longer than data")
if octets_num == 0:
- raise DecodeError("long form instead of short one")
+ raise LenIndefiniteForm()
if byte2int(data[1:]) == 0:
raise DecodeError("leading zeros")
l = 0
"offset",
"llen",
"vlen",
+ "bered",
)
def __init__(
self.optional = optional
self.offset, self.llen, self.vlen = _decoded
self.default = None
+ self.bered = False
@property
def ready(self): # pragma: no cover
offset=offset,
)
first_octet = byte2int(v)
+ bered = False
if first_octet == 0:
value = False
elif first_octet == 0xFF:
value = True
+ elif ctx.get("bered", False):
+ value = True
+ bered = True
else:
raise DecodeError(
"unacceptable Boolean value",
optional=self.optional,
_decoded=(offset, 1, 1),
)
+ obj.bered = bered
return obj, v[1:]
def __repr__(self):
>>> b.specs
{'nonRepudiation': 1, 'digitalSignature': 0, 'keyEncipherment': 2}
"""
- __slots__ = ("specs", "defined")
+ __slots__ = ("tag_constructed", "specs", "defined")
tag_default = tag_encode(3)
asn1_type_name = "BIT STRING"
if value is None:
self._value = default
self.defined = None
+ tag_klass, _, tag_num = tag_decode(self.tag)
+ self.tag_constructed = tag_encode(
+ klass=tag_klass,
+ form=TagFormConstructed,
+ num=tag_num,
+ )
def _bits2octets(self, bits):
if len(self.specs) > 0:
octets,
))
- def _decode(self, tlv, offset, decode_path, ctx, tag_only):
- try:
- t, _, lv = tag_strip(tlv)
- except DecodeError as err:
- raise err.__class__(
- msg=err.msg,
- klass=self.__class__,
- decode_path=decode_path,
- offset=offset,
- )
- if t != self.tag:
- raise TagMismatch(
- klass=self.__class__,
- decode_path=decode_path,
- offset=offset,
- )
- if tag_only:
- return
+ def _decode_chunk(self, lv, offset, decode_path, ctx):
try:
l, llen, v = len_decode(lv)
except DecodeError as err:
)
return obj, tail
+ def _decode(self, tlv, offset, decode_path, ctx, tag_only):
+ try:
+ t, tlen, lv = tag_strip(tlv)
+ except DecodeError as err:
+ raise err.__class__(
+ msg=err.msg,
+ klass=self.__class__,
+ decode_path=decode_path,
+ offset=offset,
+ )
+ if t == self.tag:
+ if tag_only:
+ return
+ return self._decode_chunk(lv, offset, decode_path, ctx)
+ if t == self.tag_constructed:
+ if not ctx.get("bered", False):
+ raise DecodeError(
+ msg="unallowed BER constructed encoding",
+ decode_path=decode_path,
+ offset=offset,
+ )
+ if tag_only:
+ return
+ eoc_expected = False
+ try:
+ l, llen, v = len_decode(lv)
+ except LenIndefiniteForm:
+ llen, l, v = 1, 0, lv[1:]
+ eoc_expected = True
+ except DecodeError as err:
+ raise err.__class__(
+ msg=err.msg,
+ klass=self.__class__,
+ decode_path=decode_path,
+ offset=offset,
+ )
+ if l > 0 and l > len(v):
+ raise NotEnoughData(
+ "encoded length is longer than data",
+ klass=self.__class__,
+ decode_path=decode_path,
+ offset=offset,
+ )
+ if not eoc_expected and l == 0:
+ raise NotEnoughData(
+ "zero length",
+ klass=self.__class__,
+ decode_path=decode_path,
+ offset=offset,
+ )
+ chunks = []
+ sub_offset = offset + tlen + llen
+ vlen = 0
+ while True:
+ if eoc_expected:
+ if v[:EOC_LEN].tobytes() == EOC:
+ break
+ else:
+ if vlen == l:
+ break
+ if vlen > l:
+ raise DecodeError(
+ msg="chunk out of bounds",
+ decode_path=len(chunks) - 1,
+ offset=chunks[-1].offset,
+ )
+ sub_decode_path = decode_path + (str(len(chunks)),)
+ try:
+ chunk, v_tail = BitString().decode(
+ v,
+ offset=sub_offset,
+ decode_path=sub_decode_path,
+ leavemm=True,
+ ctx=ctx,
+ )
+ except TagMismatch:
+ raise DecodeError(
+ msg="expected BitString encoded chunk",
+ decode_path=sub_decode_path,
+ offset=sub_offset,
+ )
+ chunks.append(chunk)
+ sub_offset += chunk.tlvlen
+ vlen += chunk.tlvlen
+ v = v_tail
+ if len(chunks) == 0:
+ raise DecodeError(
+ msg="no chunks",
+ decode_path=decode_path,
+ offset=offset,
+ )
+ values = []
+ bit_len = 0
+ for chunk_i, chunk in enumerate(chunks[:-1]):
+ if chunk.bit_len % 8 != 0:
+ raise DecodeError(
+ msg="BitString chunk is not multiple of 8 bit",
+ decode_path=decode_path + (str(chunk_i),),
+ offset=chunk.offset,
+ )
+ values.append(bytes(chunk))
+ bit_len += chunk.bit_len
+ chunk_last = chunks[-1]
+ values.append(bytes(chunk_last))
+ bit_len += chunk_last.bit_len
+ obj = self.__class__(
+ value=(bit_len, b"".join(values)),
+ impl=self.tag,
+ expl=self._expl,
+ default=self.default,
+ optional=self.optional,
+ _specs=self.specs,
+ _decoded=(offset, llen, vlen + (EOC_LEN if eoc_expected else 0)),
+ )
+ obj.bered = True
+ return obj, v[EOC_LEN if eoc_expected else 0:]
+ raise TagMismatch(
+ klass=self.__class__,
+ decode_path=decode_path,
+ offset=offset,
+ )
+
def __repr__(self):
return pp_console_row(next(self.pps()))
>>> OctetString(b"hell", bounds=(4, 4))
OCTET STRING 4 bytes 68656c6c
"""
- __slots__ = ("_bound_min", "_bound_max", "defined")
+ __slots__ = ("tag_constructed", "_bound_min", "_bound_max", "defined")
tag_default = tag_encode(4)
asn1_type_name = "OCTET STRING"
if self._value is None:
self._value = default
self.defined = None
+ tag_klass, _, tag_num = tag_decode(self.tag)
+ self.tag_constructed = tag_encode(
+ klass=tag_klass,
+ form=TagFormConstructed,
+ num=tag_num,
+ )
def _value_sanitize(self, value):
if issubclass(value.__class__, OctetString):
self._value,
))
- def _decode(self, tlv, offset, decode_path, ctx, tag_only):
- try:
- t, _, lv = tag_strip(tlv)
- except DecodeError as err:
- raise err.__class__(
- msg=err.msg,
- klass=self.__class__,
- decode_path=decode_path,
- offset=offset,
- )
- if t != self.tag:
- raise TagMismatch(
- klass=self.__class__,
- decode_path=decode_path,
- offset=offset,
- )
- if tag_only:
- return
+ def _decode_chunk(self, lv, offset, decode_path, ctx):
try:
l, llen, v = len_decode(lv)
except DecodeError as err:
)
return obj, tail
+ def _decode(self, tlv, offset, decode_path, ctx, tag_only):
+ try:
+ t, tlen, lv = tag_strip(tlv)
+ except DecodeError as err:
+ raise err.__class__(
+ msg=err.msg,
+ klass=self.__class__,
+ decode_path=decode_path,
+ offset=offset,
+ )
+ if t == self.tag:
+ if tag_only:
+ return
+ return self._decode_chunk(lv, offset, decode_path, ctx)
+ if t == self.tag_constructed:
+ if not ctx.get("bered", False):
+ raise DecodeError(
+ msg="unallowed BER constructed encoding",
+ decode_path=decode_path,
+ offset=offset,
+ )
+ if tag_only:
+ return
+ eoc_expected = False
+ try:
+ l, llen, v = len_decode(lv)
+ except LenIndefiniteForm:
+ llen, l, v = 1, 0, lv[1:]
+ eoc_expected = True
+ except DecodeError as err:
+ raise err.__class__(
+ msg=err.msg,
+ klass=self.__class__,
+ decode_path=decode_path,
+ offset=offset,
+ )
+ if l > 0 and l > len(v):
+ raise NotEnoughData(
+ "encoded length is longer than data",
+ klass=self.__class__,
+ decode_path=decode_path,
+ offset=offset,
+ )
+ if not eoc_expected and l == 0:
+ raise NotEnoughData(
+ "zero length",
+ klass=self.__class__,
+ decode_path=decode_path,
+ offset=offset,
+ )
+ chunks = []
+ sub_offset = offset + tlen + llen
+ vlen = 0
+ while True:
+ if eoc_expected:
+ if v[:EOC_LEN].tobytes() == EOC:
+ break
+ else:
+ if vlen == l:
+ break
+ if vlen > l:
+ raise DecodeError(
+ msg="chunk out of bounds",
+ decode_path=len(chunks) - 1,
+ offset=chunks[-1].offset,
+ )
+ sub_decode_path = decode_path + (str(len(chunks)),)
+ try:
+ chunk, v_tail = OctetString().decode(
+ v,
+ offset=sub_offset,
+ decode_path=sub_decode_path,
+ leavemm=True,
+ ctx=ctx,
+ )
+ except TagMismatch:
+ raise DecodeError(
+ msg="expected OctetString encoded chunk",
+ decode_path=sub_decode_path,
+ offset=sub_offset,
+ )
+ chunks.append(chunk)
+ sub_offset += chunk.tlvlen
+ vlen += chunk.tlvlen
+ v = v_tail
+ if len(chunks) == 0:
+ raise DecodeError(
+ msg="no chunks",
+ decode_path=decode_path,
+ offset=offset,
+ )
+ try:
+ obj = self.__class__(
+ value=b"".join(bytes(chunk) for chunk in chunks),
+ bounds=(self._bound_min, self._bound_max),
+ impl=self.tag,
+ expl=self._expl,
+ default=self.default,
+ optional=self.optional,
+ _decoded=(offset, llen, vlen + (EOC_LEN if eoc_expected else 0)),
+ )
+ except DecodeError as err:
+ raise DecodeError(
+ msg=err.msg,
+ klass=self.__class__,
+ decode_path=decode_path,
+ offset=offset,
+ )
+ except BoundsError as err:
+ raise DecodeError(
+ msg=str(err),
+ klass=self.__class__,
+ decode_path=decode_path,
+ offset=offset,
+ )
+ obj.bered = True
+ return obj, v[EOC_LEN if eoc_expected else 0:]
+ raise TagMismatch(
+ klass=self.__class__,
+ decode_path=decode_path,
+ offset=offset,
+ )
+
def __repr__(self):
return pp_console_row(next(self.pps()))
pyderasn.InvalidValueType: invalid value type, expected: <class 'pyderasn.ObjectIdentifier'>
>>> ext["extnID"] = ObjectIdentifier("1.2.3")
- You can know if sequence is ready to be encoded:
+ You can determine if sequence is ready to be encoded:
>>> ext.ready
False
Assign ``None`` to remove value from sequence.
- You can know if value exists/set in the sequence and take its value:
+ You can set values in Sequence during its initialization:
+
+ >>> AlgorithmIdentifier((
+ ("algorithm", ObjectIdentifier("1.2.3")),
+ ("parameters", Any(Null()))
+ ))
+ AlgorithmIdentifier SEQUENCE[OBJECT IDENTIFIER 1.2.3, ANY 0500 OPTIONAL]
+
+ You can determine if value exists/set in the sequence and take its value:
>>> "extnID" in ext, "extnValue" in ext, "critical" in ext
(True, True, False)
)
self._value = {}
if value is not None:
- self._value = self._value_sanitize(value)
+ if issubclass(value.__class__, Sequence):
+ self._value = value._value
+ elif hasattr(value, "__iter__"):
+ for seq_key, seq_value in value:
+ self[seq_key] = seq_value
+ else:
+ raise InvalidValueType((Sequence,))
if default is not None:
- default_value = self._value_sanitize(default)
+ if not issubclass(default.__class__, Sequence):
+ raise InvalidValueType((Sequence,))
+ default_value = default._value
default_obj = self.__class__(impl=self.tag, expl=self._expl)
default_obj.specs = self.specs
default_obj._value = default_value
if value is None:
self._value = default_obj.copy()._value
- def _value_sanitize(self, value):
- if not issubclass(value.__class__, Sequence):
- raise InvalidValueType((Sequence,))
- return value._value
-
@property
def ready(self):
for name, spec in self.specs.items():