]> Cypherpunks.ru repositories - pyderasn.git/blobdiff - pyderasn.py
Revert "CHOICE should proxy lenindef/bered attributed of underlying object"
[pyderasn.git] / pyderasn.py
index a7732964dedcc8befbd31da6f4778cfb1cb23dc6..88579558b731b42143a1363c07226e54f274a87e 100755 (executable)
@@ -215,6 +215,7 @@ Currently available context options:
 
 * :ref:`allow_default_values <allow_default_values_ctx>`
 * :ref:`allow_expl_oob <allow_expl_oob_ctx>`
+* :ref:`allow_unordered_set <allow_unordered_set_ctx>`
 * :ref:`bered <bered_ctx>`
 * :ref:`defines_by_path <defines_by_path_ctx>`
 
@@ -381,15 +382,21 @@ DER. But you can optionally enable BER decoding with setting ``bered``
 :ref:`context <ctx>` argument to True. Indefinite lengths and
 constructed primitive types should be parsed successfully.
 
-* If object is encoded in BER form (not the DER one), then ``bered``
+* 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`` can contain it.
+  STRING``, ``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
   contain it.
 * If object has an indefinite length encoded explicit tag, then
   ``expl_lenindef`` is set to True.
+* If object has either any of BER-related encoding (explicit tag
+  indefinite length, object's indefinite length, BER-encoding) or any
+  underlying component has that kind of encoding, then ``bered``
+  attribute is set to True. For example SignedData CMS can have
+  ``ContentInfo:content:signerInfos:*`` ``bered`` value set to True, but
+  ``ContentInfo:content:signerInfos:*:signedAttrs`` won't.
 
 EOC (end-of-contents) token's length is taken in advance in object's
 value length.
@@ -921,7 +928,7 @@ class Obj(object):
         "vlen",
         "expl_lenindef",
         "lenindef",
-        "bered",
+        "ber_encoded",
     )
 
     def __init__(
@@ -943,7 +950,7 @@ class Obj(object):
         self.default = None
         self.expl_lenindef = False
         self.lenindef = False
-        self.bered = False
+        self.ber_encoded = False
 
     @property
     def ready(self):  # pragma: no cover
@@ -951,6 +958,12 @@ class Obj(object):
         """
         raise NotImplementedError()
 
+    @property
+    def bered(self):
+        """Is either object or any elements inside is BER encoded?
+        """
+        return self.expl_lenindef or self.lenindef or self.ber_encoded
+
     def _assert_ready(self):
         if not self.ready:
             raise ObjNotReady(self.__class__.__name__)
@@ -1169,6 +1182,7 @@ class Obj(object):
                 tlen=1,
                 llen=1,
                 vlen=0,
+                ber_encoded=True,
                 bered=True,
             )
         if self.expl_lenindef:
@@ -1180,6 +1194,7 @@ class Obj(object):
                 tlen=1,
                 llen=1,
                 vlen=0,
+                ber_encoded=True,
                 bered=True,
             )
 
@@ -1231,6 +1246,7 @@ PP = namedtuple("PP", (
     "expl_vlen",
     "expl_lenindef",
     "lenindef",
+    "ber_encoded",
     "bered",
 ))
 
@@ -1255,6 +1271,7 @@ def _pp(
         expl_vlen=None,
         expl_lenindef=False,
         lenindef=False,
+        ber_encoded=False,
         bered=False,
 ):
     return PP(
@@ -1277,6 +1294,7 @@ def _pp(
         expl_vlen,
         expl_lenindef,
         lenindef,
+        ber_encoded,
         bered,
     )
 
@@ -1304,7 +1322,9 @@ def pp_console_row(
             ),
             LENINDEF_PP_CHAR if pp.expl_lenindef else " ",
         )
-        cols.append(_colourize(col, "red", with_colours, ()))
+        col = _colourize(col, "red", with_colours, ())
+        col += _colourize("B", "red", with_colours) if pp.bered else " "
+        cols.append(col)
         col = "[%d,%d,%4d]%s" % (
             pp.tlen,
             pp.llen,
@@ -1341,7 +1361,7 @@ def pp_console_row(
         cols.append(_colourize(col, "blue", with_colours))
     if pp.asn1_type_name.replace(" ", "") != pp.obj_name.upper():
         cols.append(_colourize(pp.obj_name, "magenta", with_colours))
-    if pp.bered:
+    if pp.ber_encoded:
         cols.append(_colourize("BER", "red", with_colours))
     cols.append(_colourize(pp.asn1_type_name, "cyan", with_colours))
     if pp.value is not None:
@@ -1372,7 +1392,7 @@ def pp_console_row(
 
 
 def pp_console_blob(pp, decode_path_len_decrease=0):
-    cols = [" " * len("XXXXXYYZ [X,X,XXXX]Z")]
+    cols = [" " * len("XXXXXYYZZ [X,X,XXXX]Z")]
     decode_path_len = len(pp.decode_path) - decode_path_len_decrease
     if decode_path_len > 0:
         cols.append(" ." * (decode_path_len + 1))
@@ -1604,14 +1624,14 @@ class Boolean(Obj):
                 offset=offset,
             )
         first_octet = byte2int(v)
-        bered = False
+        ber_encoded = False
         if first_octet == 0:
             value = False
         elif first_octet == 0xFF:
             value = True
         elif ctx.get("bered", False):
             value = True
-            bered = True
+            ber_encoded = True
         else:
             raise DecodeError(
                 "unacceptable Boolean value",
@@ -1627,7 +1647,7 @@ class Boolean(Obj):
             optional=self.optional,
             _decoded=(offset, 1, 1),
         )
-        obj.bered = bered
+        obj.ber_encoded = ber_encoded
         return obj, v[1:]
 
     def __repr__(self):
@@ -1652,6 +1672,7 @@ class Boolean(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):
@@ -1978,6 +1999,7 @@ class Integer(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,
+            bered=self.bered,
         )
         for pp in self.pps_lenindef(decode_path):
             yield pp
@@ -2401,7 +2423,7 @@ class BitString(Obj):
                 _decoded=(offset, llen, vlen + (EOC_LEN if lenindef else 0)),
             )
             obj.lenindef = lenindef
-            obj.bered = True
+            obj.ber_encoded = True
             return obj, (v[EOC_LEN:] if lenindef else v)
         raise TagMismatch(
             klass=self.__class__,
@@ -2440,6 +2462,7 @@ class BitString(Obj):
             expl_vlen=self.expl_vlen if self.expled else None,
             expl_lenindef=self.expl_lenindef,
             lenindef=self.lenindef,
+            ber_encoded=self.ber_encoded,
             bered=self.bered,
         )
         defined_by, defined = self.defined or (None, None)
@@ -2757,7 +2780,7 @@ class OctetString(Obj):
                     offset=offset,
                 )
             obj.lenindef = lenindef
-            obj.bered = True
+            obj.ber_encoded = True
             return obj, (v[EOC_LEN:] if lenindef else v)
         raise TagMismatch(
             klass=self.__class__,
@@ -2789,6 +2812,7 @@ class OctetString(Obj):
             expl_vlen=self.expl_vlen if self.expled else None,
             expl_lenindef=self.expl_lenindef,
             lenindef=self.lenindef,
+            ber_encoded=self.ber_encoded,
             bered=self.bered,
         )
         defined_by, defined = self.defined or (None, None)
@@ -2929,6 +2953,7 @@ class Null(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,
+            bered=self.bered,
         )
         for pp in self.pps_lenindef(decode_path):
             yield pp
@@ -3220,6 +3245,7 @@ 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,
+            bered=self.bered,
         )
         for pp in self.pps_lenindef(decode_path):
             yield pp
@@ -3445,6 +3471,8 @@ class CommonString(OctetString):
             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):
             yield pp
@@ -3647,6 +3675,8 @@ class UTCTime(CommonString):
             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):
             yield pp
@@ -3845,6 +3875,13 @@ class Choice(Obj):
     def ready(self):
         return self._value is not None and self._value[1].ready
 
+    @property
+    def bered(self):
+        return self.expl_lenindef or (
+            (self._value is not None) and
+            self._value[1].bered
+        )
+
     def copy(self):
         obj = self.__class__(schema=self.specs)
         obj._expl = self._expl
@@ -3984,6 +4021,7 @@ class Choice(Obj):
             llen=self.llen,
             vlen=self.vlen,
             expl_lenindef=self.expl_lenindef,
+            bered=self.bered,
         )
         if self.ready:
             yield self.value.pps(decode_path=decode_path + (self.choice,))
@@ -4072,6 +4110,14 @@ class Any(Obj):
     def ready(self):
         return self._value is not None
 
+    @property
+    def bered(self):
+        if self.expl_lenindef or self.lenindef:
+            return True
+        if self.defined is None:
+            return False
+        return self.defined[1].bered
+
     def copy(self):
         obj = self.__class__()
         obj._value = self._value
@@ -4206,6 +4252,7 @@ class Any(Obj):
             expl_vlen=self.expl_vlen if self.expled else None,
             expl_lenindef=self.expl_lenindef,
             lenindef=self.lenindef,
+            bered=self.bered,
         )
         defined_by, defined = self.defined or (None, None)
         if defined_by is not None:
@@ -4403,6 +4450,12 @@ class Sequence(Obj):
                     return False
         return True
 
+    @property
+    def bered(self):
+        if self.expl_lenindef or self.lenindef or self.ber_encoded:
+            return True
+        return any(value.bered for value in self._value.values())
+
     def copy(self):
         obj = self.__class__(schema=self.specs)
         obj.tag = self.tag
@@ -4537,7 +4590,7 @@ class Sequence(Obj):
         vlen = 0
         sub_offset = offset + tlen + llen
         values = {}
-        bered = False
+        ber_encoded = False
         ctx_allow_default_values = ctx.get("allow_default_values", False)
         for name, spec in self.specs.items():
             if spec.optional and (
@@ -4612,7 +4665,7 @@ class Sequence(Obj):
             v = v_tail
             if spec.default is not None and value == spec.default:
                 if ctx_bered or ctx_allow_default_values:
-                    bered = True
+                    ber_encoded = True
                 else:
                     raise DecodeError(
                         "DEFAULT value met",
@@ -4662,7 +4715,7 @@ class Sequence(Obj):
         )
         obj._value = values
         obj.lenindef = lenindef
-        obj.bered = bered
+        obj.ber_encoded = ber_encoded
         return obj, tail
 
     def __repr__(self):
@@ -4694,6 +4747,8 @@ class Sequence(Obj):
             expl_vlen=self.expl_vlen if self.expled else None,
             expl_lenindef=self.expl_lenindef,
             lenindef=self.lenindef,
+            ber_encoded=self.ber_encoded,
+            bered=self.bered,
         )
         for name in self.specs:
             value = self._value.get(name)
@@ -4708,6 +4763,14 @@ class Set(Sequence):
     """``SET`` structure type
 
     Its usage is identical to :py:class:`pyderasn.Sequence`.
+
+    .. _allow_unordered_set_ctx:
+
+    DER prohibits unordered values encoding and will raise an error
+    during decode. If If :ref:`bered <bered_ctx>` context option is set,
+    then no error will occure. Also you can disable strict values
+    ordering check by setting ``"allow_unordered_set": True``
+    :ref:`context <ctx>` option.
     """
     __slots__ = ()
     tag_default = tag_encode(form=TagFormConstructed, num=17)
@@ -4769,8 +4832,10 @@ class Set(Sequence):
         vlen = 0
         sub_offset = offset + tlen + llen
         values = {}
-        bered = False
+        ber_encoded = False
         ctx_allow_default_values = ctx.get("allow_default_values", False)
+        ctx_allow_unordered_set = ctx.get("allow_unordered_set", False)
+        value_prev = memoryview(v[:0])
         specs_items = self.specs.items
         while len(v) > 0:
             if lenindef and v[:EOC_LEN].tobytes() == EOC:
@@ -4803,13 +4868,20 @@ class Set(Sequence):
                 ctx=ctx,
             )
             value_len = value.fulllen
-            sub_offset += value_len
-            vlen += value_len
-            v = v_tail
+            if value_prev.tobytes() > v[:value_len].tobytes():
+                if ctx_bered or ctx_allow_unordered_set:
+                    ber_encoded = True
+                else:
+                    raise DecodeError(
+                        "unordered " + self.asn1_type_name,
+                        klass=self.__class__,
+                        decode_path=sub_decode_path,
+                        offset=sub_offset,
+                    )
             if spec.default is None or value != spec.default:
                 pass
             elif ctx_bered or ctx_allow_default_values:
-                bered = True
+                ber_encoded = True
             else:
                 raise DecodeError(
                     "DEFAULT value met",
@@ -4818,6 +4890,10 @@ class Set(Sequence):
                     offset=sub_offset,
                 )
             values[name] = value
+            value_prev = v[:value_len]
+            sub_offset += value_len
+            vlen += value_len
+            v = v_tail
         obj = self.__class__(
             schema=self.specs,
             impl=self.tag,
@@ -4826,8 +4902,6 @@ class Set(Sequence):
             optional=self.optional,
             _decoded=(offset, llen, vlen + (EOC_LEN if lenindef else 0)),
         )
-        obj._value = values
-        obj.bered = bered
         if lenindef:
             if v[:EOC_LEN].tobytes() != EOC:
                 raise DecodeError(
@@ -4838,6 +4912,7 @@ class Set(Sequence):
                 )
             tail = v[EOC_LEN:]
             obj.lenindef = True
+        obj._value = values
         if not obj.ready:
             raise DecodeError(
                 "not all values are ready",
@@ -4845,6 +4920,7 @@ class Set(Sequence):
                 decode_path=decode_path,
                 offset=offset,
             )
+        obj.ber_encoded = ber_encoded
         return obj, tail
 
 
@@ -4943,6 +5019,12 @@ class SequenceOf(Obj):
     def ready(self):
         return all(v.ready for v in self._value)
 
+    @property
+    def bered(self):
+        if self.expl_lenindef or self.lenindef or self.ber_encoded:
+            return True
+        return any(v.bered for v in self._value)
+
     def copy(self):
         obj = self.__class__(schema=self.spec)
         obj._bound_min = self._bound_min
@@ -5028,7 +5110,7 @@ class SequenceOf(Obj):
         v = b"".join(self._encoded_values())
         return b"".join((self.tag, len_encode(len(v)), v))
 
-    def _decode(self, tlv, offset, decode_path, ctx, tag_only):
+    def _decode(self, tlv, offset, decode_path, ctx, tag_only, ordering_check=False):
         try:
             t, tlen, lv = tag_strip(tlv)
         except DecodeError as err:
@@ -5047,10 +5129,11 @@ class SequenceOf(Obj):
         if tag_only:
             return
         lenindef = False
+        ctx_bered = ctx.get("bered", False)
         try:
             l, llen, v = len_decode(lv)
         except LenIndefForm as err:
-            if not ctx.get("bered", False):
+            if not ctx_bered:
                 raise err.__class__(
                     msg=err.msg,
                     klass=self.__class__,
@@ -5078,22 +5161,38 @@ class SequenceOf(Obj):
         vlen = 0
         sub_offset = offset + tlen + llen
         _value = []
+        ctx_allow_unordered_set = ctx.get("allow_unordered_set", False)
+        value_prev = memoryview(v[:0])
+        ber_encoded = False
         spec = self.spec
         while len(v) > 0:
             if lenindef and v[:EOC_LEN].tobytes() == EOC:
                 break
+            sub_decode_path = decode_path + (str(len(_value)),)
             value, v_tail = spec.decode(
                 v,
                 sub_offset,
                 leavemm=True,
-                decode_path=decode_path + (str(len(_value)),),
+                decode_path=sub_decode_path,
                 ctx=ctx,
             )
             value_len = value.fulllen
+            if ordering_check:
+                if value_prev.tobytes() > v[:value_len].tobytes():
+                    if ctx_bered or ctx_allow_unordered_set:
+                        ber_encoded = True
+                    else:
+                        raise DecodeError(
+                            "unordered " + self.asn1_type_name,
+                            klass=self.__class__,
+                            decode_path=sub_decode_path,
+                            offset=sub_offset,
+                        )
+                value_prev = v[:value_len]
+            _value.append(value)
             sub_offset += value_len
             vlen += value_len
             v = v_tail
-            _value.append(value)
         try:
             obj = self.__class__(
                 value=_value,
@@ -5122,6 +5221,7 @@ class SequenceOf(Obj):
                 )
             obj.lenindef = True
             tail = v[EOC_LEN:]
+        obj.ber_encoded = ber_encoded
         return obj, tail
 
     def __repr__(self):
@@ -5149,6 +5249,8 @@ class SequenceOf(Obj):
             expl_vlen=self.expl_vlen if self.expled else None,
             expl_lenindef=self.expl_lenindef,
             lenindef=self.lenindef,
+            ber_encoded=self.ber_encoded,
+            bered=self.bered,
         )
         for i, value in enumerate(self._value):
             yield value.pps(decode_path=decode_path + (str(i),))
@@ -5171,6 +5273,16 @@ class SetOf(SequenceOf):
         v = b"".join(raws)
         return b"".join((self.tag, len_encode(len(v)), v))
 
+    def _decode(self, tlv, offset, decode_path, ctx, tag_only):
+        return super(SetOf, self)._decode(
+            tlv,
+            offset,
+            decode_path,
+            ctx,
+            tag_only,
+            ordering_check=True,
+        )
+
 
 def obj_by_path(pypath):  # pragma: no cover
     """Import object specified as string Python path