X-Git-Url: http://www.git.cypherpunks.ru/?p=pyderasn.git;a=blobdiff_plain;f=pyderasn.py;h=ed5b763ccef4123c790d52569d9b376ef2acf168;hp=0d2d3f5a2982d27fbe49239139c7a01919469104;hb=ad6ac8681ad5479b7274165a056624433e0ca2f1;hpb=a41b107369d403a134c34813ed88ea6808590640 diff --git a/pyderasn.py b/pyderasn.py index 0d2d3f5..ed5b763 100755 --- a/pyderasn.py +++ b/pyderasn.py @@ -2630,64 +2630,6 @@ class BitString(Obj): octets, )) - def _decode_chunk(self, lv, offset, decode_path): - try: - l, llen, v = len_decode(lv) - except DecodeError as err: - raise err.__class__( - msg=err.msg, - klass=self.__class__, - decode_path=decode_path, - offset=offset, - ) - if l > len(v): - raise NotEnoughData( - "encoded length is longer than data", - klass=self.__class__, - decode_path=decode_path, - offset=offset, - ) - if l == 0: - raise NotEnoughData( - "zero length", - klass=self.__class__, - decode_path=decode_path, - offset=offset, - ) - pad_size = byte2int(v) - if l == 1 and pad_size != 0: - raise DecodeError( - "invalid empty value", - klass=self.__class__, - decode_path=decode_path, - offset=offset, - ) - if pad_size > 7: - raise DecodeError( - "too big pad", - klass=self.__class__, - decode_path=decode_path, - offset=offset, - ) - if byte2int(v[l - 1:l]) & ((1 << pad_size) - 1) != 0: - raise DecodeError( - "invalid pad", - klass=self.__class__, - decode_path=decode_path, - offset=offset, - ) - v, tail = v[:l], v[l:] - obj = self.__class__( - value=((len(v) - 1) * 8 - pad_size, v[1:].tobytes()), - impl=self.tag, - expl=self._expl, - default=self.default, - optional=self.optional, - _specs=self.specs, - _decoded=(offset, llen, l), - ) - return obj, tail - def _decode(self, tlv, offset, decode_path, ctx, tag_only): try: t, tlen, lv = tag_strip(tlv) @@ -2701,23 +2643,8 @@ class BitString(Obj): if t == self.tag: if tag_only: # pragma: no cover return None - return self._decode_chunk(lv, offset, decode_path) - if t == self.tag_constructed: - if not ctx.get("bered", False): - raise DecodeError( - "unallowed BER constructed encoding", - klass=self.__class__, - decode_path=decode_path, - offset=offset, - ) - if tag_only: # pragma: no cover - return None - lenindef = False try: l, llen, v = len_decode(lv) - except LenIndefForm: - llen, l, v = 1, 0, lv[1:] - lenindef = True except DecodeError as err: raise err.__class__( msg=err.msg, @@ -2732,90 +2659,160 @@ class BitString(Obj): decode_path=decode_path, offset=offset, ) - if not lenindef and l == 0: + if 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 lenindef: - if v[:EOC_LEN].tobytes() == EOC: - break - else: - if vlen == l: - break - if vlen > l: - raise DecodeError( - "chunk out of bounds", - klass=self.__class__, - decode_path=decode_path + (str(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, - _ctx_immutable=False, - ) - except TagMismatch: - raise DecodeError( - "expected BitString encoded chunk", - klass=self.__class__, - 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: + pad_size = byte2int(v) + if l == 1 and pad_size != 0: raise DecodeError( - "no chunks", + "invalid empty value", klass=self.__class__, 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( - "BitString chunk is not multiple of 8 bits", - klass=self.__class__, - 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 + if pad_size > 7: + raise DecodeError( + "too big pad", + klass=self.__class__, + decode_path=decode_path, + offset=offset, + ) + if byte2int(v[l - 1:l]) & ((1 << pad_size) - 1) != 0: + raise DecodeError( + "invalid pad", + klass=self.__class__, + decode_path=decode_path, + offset=offset, + ) + v, tail = v[:l], v[l:] obj = self.__class__( - value=(bit_len, b"".join(values)), + value=((len(v) - 1) * 8 - pad_size, v[1:].tobytes()), impl=self.tag, expl=self._expl, default=self.default, optional=self.optional, _specs=self.specs, - _decoded=(offset, llen, vlen + (EOC_LEN if lenindef else 0)), + _decoded=(offset, llen, l), ) - obj.lenindef = lenindef - obj.ber_encoded = True - return obj, (v[EOC_LEN:] if lenindef else v) - raise TagMismatch( - klass=self.__class__, - decode_path=decode_path, - offset=offset, + return obj, tail + if t != self.tag_constructed: + raise TagMismatch( + klass=self.__class__, + decode_path=decode_path, + offset=offset, + ) + if not ctx.get("bered", False): + raise DecodeError( + "unallowed BER constructed encoding", + klass=self.__class__, + decode_path=decode_path, + offset=offset, + ) + if tag_only: # pragma: no cover + return None + lenindef = False + try: + l, llen, v = len_decode(lv) + except LenIndefForm: + llen, l, v = 1, 0, lv[1:] + lenindef = True + except DecodeError as err: + raise err.__class__( + msg=err.msg, + klass=self.__class__, + decode_path=decode_path, + offset=offset, + ) + if l > len(v): + raise NotEnoughData( + "encoded length is longer than data", + klass=self.__class__, + decode_path=decode_path, + offset=offset, + ) + if not lenindef 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 lenindef: + if v[:EOC_LEN].tobytes() == EOC: + break + else: + if vlen == l: + break + if vlen > l: + raise DecodeError( + "chunk out of bounds", + klass=self.__class__, + decode_path=decode_path + (str(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, + _ctx_immutable=False, + ) + except TagMismatch: + raise DecodeError( + "expected BitString encoded chunk", + klass=self.__class__, + 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( + "no chunks", + klass=self.__class__, + 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( + "BitString chunk is not multiple of 8 bits", + klass=self.__class__, + 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 lenindef else 0)), ) + obj.lenindef = lenindef + obj.ber_encoded = True + return obj, (v[EOC_LEN:] if lenindef else v) def __repr__(self): return pp_console_row(next(self.pps())) @@ -3056,51 +3053,6 @@ class OctetString(Obj): self._value, )) - def _decode_chunk(self, lv, offset, decode_path, ctx): - try: - l, llen, v = len_decode(lv) - except DecodeError as err: - raise err.__class__( - msg=err.msg, - klass=self.__class__, - decode_path=decode_path, - offset=offset, - ) - if l > len(v): - raise NotEnoughData( - "encoded length is longer than data", - klass=self.__class__, - decode_path=decode_path, - offset=offset, - ) - v, tail = v[:l], v[l:] - try: - obj = self.__class__( - value=v.tobytes(), - bounds=(self._bound_min, self._bound_max), - impl=self.tag, - expl=self._expl, - default=self.default, - optional=self.optional, - _decoded=(offset, llen, l), - ctx=ctx, - ) - 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, - ) - return obj, tail - def _decode(self, tlv, offset, decode_path, ctx, tag_only): try: t, tlen, lv = tag_strip(tlv) @@ -3114,23 +3066,8 @@ class OctetString(Obj): if t == self.tag: if tag_only: return None - return self._decode_chunk(lv, offset, decode_path, ctx) - if t == self.tag_constructed: - if not ctx.get("bered", False): - raise DecodeError( - "unallowed BER constructed encoding", - klass=self.__class__, - decode_path=decode_path, - offset=offset, - ) - if tag_only: - return None - lenindef = False try: l, llen, v = len_decode(lv) - except LenIndefForm: - llen, l, v = 1, 0, lv[1:] - lenindef = True except DecodeError as err: raise err.__class__( msg=err.msg, @@ -3145,53 +3082,16 @@ class OctetString(Obj): decode_path=decode_path, offset=offset, ) - chunks = [] - sub_offset = offset + tlen + llen - vlen = 0 - while True: - if lenindef: - if v[:EOC_LEN].tobytes() == EOC: - break - else: - if vlen == l: - break - if vlen > l: - raise DecodeError( - "chunk out of bounds", - klass=self.__class__, - decode_path=decode_path + (str(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, - _ctx_immutable=False, - ) - except TagMismatch: - raise DecodeError( - "expected OctetString encoded chunk", - klass=self.__class__, - decode_path=sub_decode_path, - offset=sub_offset, - ) - chunks.append(chunk) - sub_offset += chunk.tlvlen - vlen += chunk.tlvlen - v = v_tail + v, tail = v[:l], v[l:] try: obj = self.__class__( - value=b"".join(bytes(chunk) for chunk in chunks), + value=v.tobytes(), 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 lenindef else 0)), + _decoded=(offset, llen, l), ctx=ctx, ) except DecodeError as err: @@ -3208,14 +3108,108 @@ class OctetString(Obj): decode_path=decode_path, offset=offset, ) - obj.lenindef = lenindef - obj.ber_encoded = True - return obj, (v[EOC_LEN:] if lenindef else v) - raise TagMismatch( - klass=self.__class__, - decode_path=decode_path, - offset=offset, - ) + return obj, tail + if t != self.tag_constructed: + raise TagMismatch( + klass=self.__class__, + decode_path=decode_path, + offset=offset, + ) + if not ctx.get("bered", False): + raise DecodeError( + "unallowed BER constructed encoding", + klass=self.__class__, + decode_path=decode_path, + offset=offset, + ) + if tag_only: + return None + lenindef = False + try: + l, llen, v = len_decode(lv) + except LenIndefForm: + llen, l, v = 1, 0, lv[1:] + lenindef = True + except DecodeError as err: + raise err.__class__( + msg=err.msg, + klass=self.__class__, + decode_path=decode_path, + offset=offset, + ) + if l > len(v): + raise NotEnoughData( + "encoded length is longer than data", + klass=self.__class__, + decode_path=decode_path, + offset=offset, + ) + chunks = [] + sub_offset = offset + tlen + llen + vlen = 0 + while True: + if lenindef: + if v[:EOC_LEN].tobytes() == EOC: + break + else: + if vlen == l: + break + if vlen > l: + raise DecodeError( + "chunk out of bounds", + klass=self.__class__, + decode_path=decode_path + (str(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, + _ctx_immutable=False, + ) + except TagMismatch: + raise DecodeError( + "expected OctetString encoded chunk", + klass=self.__class__, + decode_path=sub_decode_path, + offset=sub_offset, + ) + chunks.append(chunk) + sub_offset += chunk.tlvlen + vlen += chunk.tlvlen + v = v_tail + 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 lenindef else 0)), + ctx=ctx, + ) + 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.lenindef = lenindef + obj.ber_encoded = True + return obj, (v[EOC_LEN:] if lenindef else v) def __repr__(self): return pp_console_row(next(self.pps())) @@ -5822,13 +5816,14 @@ class Set(Sequence): tail = v[EOC_LEN:] obj.lenindef = True obj._value = values - if not obj.ready: - raise DecodeError( - "not all values are ready", - klass=self.__class__, - decode_path=decode_path, - offset=offset, - ) + for name, spec in iteritems(self.specs): + if name not in values and not spec.optional: + raise DecodeError( + "%s value is not ready" % name, + klass=self.__class__, + decode_path=decode_path, + offset=offset, + ) obj.ber_encoded = ber_encoded return obj, tail