X-Git-Url: http://www.git.cypherpunks.ru/?a=blobdiff_plain;f=pyderasn.py;h=516036862de84a150bd57bd8f29941da40985393;hb=3ad9ef9200070276702491f2bb2e3f49cba013f4;hp=2e63b5a2320bc672bf7d01f35acb053d241b3145;hpb=a441b706391d96088555054663cafa5aa244c592;p=pyderasn.git diff --git a/pyderasn.py b/pyderasn.py index 2e63b5a..5160368 100755 --- a/pyderasn.py +++ b/pyderasn.py @@ -1,7 +1,7 @@ #!/usr/bin/env python # coding: utf-8 # PyDERASN -- Python ASN.1 DER/BER codec with abstract structures -# Copyright (C) 2017-2018 Sergey Matveev +# Copyright (C) 2017-2019 Sergey Matveev # # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU Lesser General Public License as @@ -384,7 +384,8 @@ constructed primitive types should be parsed successfully. * If object is encoded in BER form (not the DER one), then ``ber_encoded`` attribute is set to True. Only ``BOOLEAN``, ``BIT STRING``, ``OCTET - STRING``, ``SEQUENCE``, ``SET``, ``SET OF`` can contain it. + STRING``, ``OBJECT IDENTIFIER``, ``SEQUENCE``, ``SET``, ``SET OF`` + can contain it. * If object has an indefinite length encoding, then its ``lenindef`` attribute is set to True. Only ``BIT STRING``, ``OCTET STRING``, ``SEQUENCE``, ``SET``, ``SEQUENCE OF``, ``SET OF``, ``ANY`` can @@ -515,6 +516,7 @@ Various ------- .. autofunction:: pyderasn.abs_decode_path +.. autofunction:: pyderasn.colonize_hex .. autofunction:: pyderasn.hexenc .. autofunction:: pyderasn.hexdec .. autofunction:: pyderasn.tag_encode @@ -539,9 +541,11 @@ from codecs import getdecoder from codecs import getencoder from collections import namedtuple from collections import OrderedDict +from copy import copy from datetime import datetime from math import ceil from os import environ +from string import ascii_letters from string import digits from six import add_metaclass @@ -554,6 +558,7 @@ from six import iterbytes from six import PY2 from six import string_types from six import text_type +from six import unichr as six_unichr from six.moves import xrange as six_xrange @@ -641,7 +646,11 @@ LENINDEF_PP_CHAR = "I" if PY2 else "∞" # Errors ######################################################################## -class DecodeError(Exception): +class ASN1Error(ValueError): + pass + + +class DecodeError(ASN1Error): def __init__(self, msg="", klass=None, decode_path=(), offset=0): """ :param str msg: reason of decode failing @@ -696,7 +705,7 @@ class InvalidOID(DecodeError): pass -class ObjUnknown(ValueError): +class ObjUnknown(ASN1Error): def __init__(self, name): super(ObjUnknown, self).__init__() self.name = name @@ -708,7 +717,7 @@ class ObjUnknown(ValueError): return "%s(%s)" % (self.__class__.__name__, self) -class ObjNotReady(ValueError): +class ObjNotReady(ASN1Error): def __init__(self, name): super(ObjNotReady, self).__init__() self.name = name @@ -720,7 +729,7 @@ class ObjNotReady(ValueError): return "%s(%s)" % (self.__class__.__name__, self) -class InvalidValueType(ValueError): +class InvalidValueType(ASN1Error): def __init__(self, expected_types): super(InvalidValueType, self).__init__() self.expected_types = expected_types @@ -734,7 +743,7 @@ class InvalidValueType(ValueError): return "%s(%s)" % (self.__class__.__name__, self) -class BoundsError(ValueError): +class BoundsError(ASN1Error): def __init__(self, bound_min, value, bound_max): super(BoundsError, self).__init__() self.bound_min = bound_min @@ -1022,6 +1031,7 @@ class Obj(object): decode_path=(), ctx=None, tag_only=False, + _ctx_immutable=True, ): """Decode the data @@ -1029,14 +1039,17 @@ class Obj(object): :param int offset: initial data's offset :param bool leavemm: do we need to leave memoryview of remaining data as is, or convert it to bytes otherwise - :param ctx: optional :ref:`context ` governing decoding process. + :param ctx: optional :ref:`context ` governing decoding process :param tag_only: decode only the tag, without length and contents (used only in Choice and Set structures, trying to determine if tag satisfies the scheme) + :param _ctx_immutable: do we need to copy ``ctx`` before using it :returns: (Obj, remaining data) """ if ctx is None: ctx = {} + elif _ctx_immutable: + ctx = copy(ctx) tlv = memoryview(data) if self._expl is None: result = self._decode( @@ -1230,6 +1243,7 @@ class DecodePathDefBy(object): ######################################################################## PP = namedtuple("PP", ( + "obj", "asn1_type_name", "obj_name", "decode_path", @@ -1255,6 +1269,7 @@ PP = namedtuple("PP", ( def _pp( + obj=None, asn1_type_name="unknown", obj_name="unknown", decode_path=(), @@ -1278,6 +1293,7 @@ def _pp( bered=False, ): return PP( + obj, asn1_type_name, obj_name, decode_path, @@ -1306,6 +1322,12 @@ def _colourize(what, colour, with_colours, attrs=("bold",)): return colored(what, colour, attrs=attrs) if with_colours else what +def colonize_hex(hexed): + """Separate hexadecimal string with colons + """ + return ":".join(hexed[i:i + 2] for i in range(0, len(hexed), 2)) + + def pp_console_row( pp, oids=None, @@ -1376,6 +1398,15 @@ def pp_console_row( value in oids ): cols.append(_colourize("(%s)" % oids[value], "green", with_colours)) + if pp.asn1_type_name == Integer.asn1_type_name: + hex_repr = hex(int(pp.obj._value))[2:].upper() + if len(hex_repr) % 2 != 0: + hex_repr = "0" + hex_repr + cols.append(_colourize( + "(%s)" % colonize_hex(hex_repr), + "green", + with_colours, + )) if with_blob: if isinstance(pp.blob, binary_type): cols.append(hexenc(pp.blob)) @@ -1403,9 +1434,7 @@ def pp_console_blob(pp, decode_path_len_decrease=0): blob = hexenc(pp.blob).upper() for i in range(0, len(blob), 32): chunk = blob[i:i + 32] - yield " ".join(cols + [":".join( - chunk[j:j + 2] for j in range(0, len(chunk), 2) - )]) + yield " ".join(cols + [colonize_hex(chunk)]) elif isinstance(pp.blob, tuple): yield " ".join(cols + [", ".join(pp.blob)]) @@ -1658,6 +1687,7 @@ class Boolean(Obj): def pps(self, decode_path=()): yield _pp( + obj=self, asn1_type_name=self.asn1_type_name, obj_name=self.__class__.__name__, decode_path=decode_path, @@ -1985,6 +2015,7 @@ class Integer(Obj): def pps(self, decode_path=()): yield _pp( + obj=self, asn1_type_name=self.asn1_type_name, obj_name=self.__class__.__name__, decode_path=decode_path, @@ -2382,6 +2413,7 @@ class BitString(Obj): decode_path=sub_decode_path, leavemm=True, ctx=ctx, + _ctx_immutable=False, ) except TagMismatch: raise DecodeError( @@ -2446,6 +2478,7 @@ class BitString(Obj): if len(self.specs) > 0: blob = tuple(self.named) yield _pp( + obj=self, asn1_type_name=self.asn1_type_name, obj_name=self.__class__.__name__, decode_path=decode_path, @@ -2746,6 +2779,7 @@ class OctetString(Obj): decode_path=sub_decode_path, leavemm=True, ctx=ctx, + _ctx_immutable=False, ) except TagMismatch: raise DecodeError( @@ -2796,6 +2830,7 @@ class OctetString(Obj): def pps(self, decode_path=()): yield _pp( + obj=self, asn1_type_name=self.asn1_type_name, obj_name=self.__class__.__name__, decode_path=decode_path, @@ -2941,6 +2976,7 @@ class Null(Obj): def pps(self, decode_path=()): yield _pp( + obj=self, asn1_type_name=self.asn1_type_name, obj_name=self.__class__.__name__, decode_path=decode_path, @@ -3188,11 +3224,17 @@ class ObjectIdentifier(Obj): ) v, tail = v[:l], v[l:] arcs = [] + ber_encoded = False while len(v) > 0: i = 0 arc = 0 while True: octet = indexbytes(v, i) + if i == 0 and octet == 0x80: + if ctx.get("bered", False): + ber_encoded = True + else: + raise DecodeError("non normalized arc encoding") arc = (arc << 7) | (octet & 0x7F) if octet & 0x80 == 0: arcs.append(arc) @@ -3224,6 +3266,8 @@ class ObjectIdentifier(Obj): optional=self.optional, _decoded=(offset, llen, l), ) + if ber_encoded: + obj.ber_encoded = True return obj, tail def __repr__(self): @@ -3231,6 +3275,7 @@ class ObjectIdentifier(Obj): def pps(self, decode_path=()): yield _pp( + obj=self, asn1_type_name=self.asn1_type_name, obj_name=self.__class__.__name__, decode_path=decode_path, @@ -3248,6 +3293,7 @@ class ObjectIdentifier(Obj): expl_llen=self.expl_llen if self.expled else None, expl_vlen=self.expl_vlen if self.expled else None, expl_lenindef=self.expl_lenindef, + ber_encoded=self.ber_encoded, bered=self.bered, ) for pp in self.pps_lenindef(decode_path): @@ -3457,6 +3503,7 @@ class CommonString(OctetString): if self.ready: value = hexenc(bytes(self)) if no_unicode else self.__unicode__() yield _pp( + obj=self, asn1_type_name=self.asn1_type_name, obj_name=self.__class__.__name__, decode_path=decode_path, @@ -3488,29 +3535,57 @@ class UTF8String(CommonString): asn1_type_name = "UTF8String" -class NumericString(CommonString): +class AllowableCharsMixin(object): + @property + def allowable_chars(self): + if PY2: + return self._allowable_chars + return set(six_unichr(c) for c in self._allowable_chars) + + +class NumericString(AllowableCharsMixin, CommonString): """Numeric string - Its value is properly sanitized: only ASCII digits can be stored. + Its value is properly sanitized: only ASCII digits with spaces can + be stored. + + >>> NumericString().allowable_chars + set(['3', '4', '7', '5', '1', '0', '8', '9', ' ', '6', '2']) """ __slots__ = () tag_default = tag_encode(18) encoding = "ascii" asn1_type_name = "NumericString" - allowable_chars = set(digits.encode("ascii")) + _allowable_chars = set(digits.encode("ascii") + b" ") def _value_sanitize(self, value): value = super(NumericString, self)._value_sanitize(value) - if not set(value) <= self.allowable_chars: + if not set(value) <= self._allowable_chars: raise DecodeError("non-numeric value") return value -class PrintableString(CommonString): +class PrintableString(AllowableCharsMixin, CommonString): + """Printable string + + Its value is properly sanitized: see X.680 41.4 table 10. + + >>> PrintableString().allowable_chars + >>> set([' ', "'", ..., 'z']) + """ __slots__ = () tag_default = tag_encode(19) encoding = "ascii" asn1_type_name = "PrintableString" + _allowable_chars = set( + (ascii_letters + digits + " '()+,-./:=?").encode("ascii") + ) + + def _value_sanitize(self, value): + value = super(PrintableString, self)._value_sanitize(value) + if not set(value) <= self._allowable_chars: + raise DecodeError("non-printable value") + return value class TeletexString(CommonString): @@ -3661,6 +3736,7 @@ class UTCTime(CommonString): def pps(self, decode_path=()): yield _pp( + obj=self, asn1_type_name=self.asn1_type_name, obj_name=self.__class__.__name__, decode_path=decode_path, @@ -3974,6 +4050,7 @@ class Choice(Obj): decode_path=sub_decode_path, ctx=ctx, tag_only=True, + _ctx_immutable=False, ) except TagMismatch: continue @@ -3992,6 +4069,7 @@ class Choice(Obj): leavemm=True, decode_path=sub_decode_path, ctx=ctx, + _ctx_immutable=False, ) obj = self.__class__( schema=self.specs, @@ -4011,6 +4089,7 @@ class Choice(Obj): def pps(self, decode_path=()): yield _pp( + obj=self, asn1_type_name=self.asn1_type_name, obj_name=self.__class__.__name__, decode_path=decode_path, @@ -4193,6 +4272,7 @@ class Any(Obj): decode_path=decode_path + (str(chunk_i),), leavemm=True, ctx=ctx, + _ctx_immutable=False, ) vlen += chunk.tlvlen sub_offset += chunk.tlvlen @@ -4237,6 +4317,7 @@ class Any(Obj): def pps(self, decode_path=()): yield _pp( + obj=self, asn1_type_name=self.asn1_type_name, obj_name=self.__class__.__name__, decode_path=decode_path, @@ -4286,8 +4367,7 @@ def get_def_by_path(defines_by_path, sub_decode_path): def abs_decode_path(decode_path, rel_path): """Create an absolute decode path from current and relative ones - :param decode_path: current decode path, starting point. - Tuple of strings + :param decode_path: current decode path, starting point. Tuple of strings :param rel_path: relative path to ``decode_path``. Tuple of strings. If first tuple's element is "/", then treat it as an absolute path, ignoring ``decode_path`` as @@ -4609,6 +4689,7 @@ class Sequence(Obj): leavemm=True, decode_path=sub_decode_path, ctx=ctx, + _ctx_immutable=False, ) except TagMismatch: if spec.optional: @@ -4633,6 +4714,7 @@ class Sequence(Obj): leavemm=True, decode_path=sub_sub_decode_path, ctx=ctx, + _ctx_immutable=False, ) if len(defined_tail) > 0: raise DecodeError( @@ -4652,6 +4734,7 @@ class Sequence(Obj): leavemm=True, decode_path=sub_decode_path + (DecodePathDefBy(defined_by),), ctx=ctx, + _ctx_immutable=False, ) if len(defined_tail) > 0: raise DecodeError( @@ -4733,6 +4816,7 @@ class Sequence(Obj): def pps(self, decode_path=()): yield _pp( + obj=self, asn1_type_name=self.asn1_type_name, obj_name=self.__class__.__name__, decode_path=decode_path, @@ -4853,6 +4937,7 @@ class Set(Sequence): decode_path=sub_decode_path, ctx=ctx, tag_only=True, + _ctx_immutable=False, ) except TagMismatch: continue @@ -4869,6 +4954,7 @@ class Set(Sequence): leavemm=True, decode_path=sub_decode_path, ctx=ctx, + _ctx_immutable=False, ) value_len = value.fulllen if value_prev.tobytes() > v[:value_len].tobytes(): @@ -5178,6 +5264,7 @@ class SequenceOf(Obj): leavemm=True, decode_path=sub_decode_path, ctx=ctx, + _ctx_immutable=False, ) value_len = value.fulllen if ordering_check: @@ -5235,6 +5322,7 @@ class SequenceOf(Obj): def pps(self, decode_path=()): yield _pp( + obj=self, asn1_type_name=self.asn1_type_name, obj_name=self.__class__.__name__, decode_path=decode_path,