X-Git-Url: http://www.git.cypherpunks.ru/?a=blobdiff_plain;f=pyderasn.py;h=4142af690d616b316ac46494dfde8857fcb25a02;hb=863d21e01e95ba9f1626159b6997c794e0cc11a5;hp=9a8ccddfa319df841e98a94ac4950f9b6f308c3d;hpb=e7a4b259f8cd580f52160c17842d797fc3ddf7dc;p=pyderasn.git diff --git a/pyderasn.py b/pyderasn.py index 9a8ccdd..4142af6 100755 --- a/pyderasn.py +++ b/pyderasn.py @@ -539,6 +539,7 @@ 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 @@ -555,6 +556,7 @@ 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 @@ -642,7 +644,11 @@ 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 @@ -697,7 +703,7 @@ class InvalidOID(DecodeError): pass -class ObjUnknown(ValueError): +class ObjUnknown(ASN1Error): def __init__(self, name): super(ObjUnknown, self).__init__() self.name = name @@ -709,7 +715,7 @@ 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 @@ -721,7 +727,7 @@ 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 @@ -735,7 +741,7 @@ 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 @@ -1023,6 +1029,7 @@ class Obj(object): decode_path=(), ctx=None, tag_only=False, + _ctx_immutable=True, ): """Decode the data @@ -1030,14 +1037,17 @@ 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( @@ -2383,6 +2393,7 @@ class BitString(Obj): decode_path=sub_decode_path, leavemm=True, ctx=ctx, + _ctx_immutable=False, ) except TagMismatch: raise DecodeError( @@ -2747,6 +2758,7 @@ class OctetString(Obj): decode_path=sub_decode_path, leavemm=True, ctx=ctx, + _ctx_immutable=False, ) except TagMismatch: raise DecodeError( @@ -3489,34 +3501,55 @@ 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") + b" ") + _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")) + _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: + if not set(value) <= self._allowable_chars: raise DecodeError("non-printable value") return value @@ -3982,6 +4015,7 @@ class Choice(Obj): decode_path=sub_decode_path, ctx=ctx, tag_only=True, + _ctx_immutable=False, ) except TagMismatch: continue @@ -4000,6 +4034,7 @@ class Choice(Obj): leavemm=True, decode_path=sub_decode_path, ctx=ctx, + _ctx_immutable=False, ) obj = self.__class__( schema=self.specs, @@ -4201,6 +4236,7 @@ class Any(Obj): decode_path=decode_path + (str(chunk_i),), leavemm=True, ctx=ctx, + _ctx_immutable=False, ) vlen += chunk.tlvlen sub_offset += chunk.tlvlen @@ -4294,8 +4330,7 @@ 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 @@ -4617,6 +4652,7 @@ class Sequence(Obj): leavemm=True, decode_path=sub_decode_path, ctx=ctx, + _ctx_immutable=False, ) except TagMismatch: if spec.optional: @@ -4641,6 +4677,7 @@ class Sequence(Obj): leavemm=True, decode_path=sub_sub_decode_path, ctx=ctx, + _ctx_immutable=False, ) if len(defined_tail) > 0: raise DecodeError( @@ -4660,6 +4697,7 @@ 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( @@ -4861,6 +4899,7 @@ class Set(Sequence): decode_path=sub_decode_path, ctx=ctx, tag_only=True, + _ctx_immutable=False, ) except TagMismatch: continue @@ -4877,6 +4916,7 @@ 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(): @@ -5186,6 +5226,7 @@ class SequenceOf(Obj): leavemm=True, decode_path=sub_decode_path, ctx=ctx, + _ctx_immutable=False, ) value_len = value.fulllen if ordering_check: