]> Cypherpunks.ru repositories - pyderasn.git/blobdiff - pyderasn.py
More test coverage
[pyderasn.git] / pyderasn.py
index 6db8017e12a60a7d7ddfa4202514c31f808bd39e..2e63b5a2320bc672bf7d01f35acb053d241b3145 100755 (executable)
@@ -213,10 +213,11 @@ decoding process.
 
 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>`
-* :ref:`strict_default_existence <strict_default_existence_ctx>`
 
 .. _pprinting:
 
@@ -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`` 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.
@@ -552,7 +559,7 @@ from six.moves import xrange as six_xrange
 
 try:
     from termcolor import colored
-except ImportError:
+except ImportError:  # pragma: no cover
     def colored(what, *args):
         return what
 
@@ -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
@@ -955,6 +962,12 @@ class Obj(object):
         if not self.ready:
             raise ObjNotReady(self.__class__.__name__)
 
+    @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
+
     @property
     def decoded(self):
         """Is object decoded?
@@ -1071,7 +1084,7 @@ class Obj(object):
                     ctx=ctx,
                     tag_only=tag_only,
                 )
-                if tag_only:
+                if tag_only:  # pragma: no cover
                     return
                 obj, tail = result
                 eoc_expected, tail = tail[:EOC_LEN], tail[EOC_LEN:]
@@ -1106,7 +1119,7 @@ class Obj(object):
                     ctx=ctx,
                     tag_only=tag_only,
                 )
-                if tag_only:
+                if tag_only:  # pragma: no cover
                     return
                 obj, tail = result
                 if obj.tlvlen < l and not ctx.get("allow_expl_oob", False):
@@ -1157,7 +1170,10 @@ class Obj(object):
         return self.expl_tlvlen if self.expled else self.tlvlen
 
     def pps_lenindef(self, decode_path):
-        if self.lenindef:
+        if self.lenindef and not (
+            getattr(self, "defined", None) is not None and
+            self.defined[1].lenindef
+        ):
             yield _pp(
                 asn1_type_name="EOC",
                 obj_name="",
@@ -1169,6 +1185,7 @@ class Obj(object):
                 tlen=1,
                 llen=1,
                 vlen=0,
+                ber_encoded=True,
                 bered=True,
             )
         if self.expl_lenindef:
@@ -1180,6 +1197,7 @@ class Obj(object):
                 tlen=1,
                 llen=1,
                 vlen=0,
+                ber_encoded=True,
                 bered=True,
             )
 
@@ -1231,6 +1249,7 @@ PP = namedtuple("PP", (
     "expl_vlen",
     "expl_lenindef",
     "lenindef",
+    "ber_encoded",
     "bered",
 ))
 
@@ -1255,6 +1274,7 @@ def _pp(
         expl_vlen=None,
         expl_lenindef=False,
         lenindef=False,
+        ber_encoded=False,
         bered=False,
 ):
     return PP(
@@ -1277,6 +1297,7 @@ def _pp(
         expl_vlen,
         expl_lenindef,
         lenindef,
+        ber_encoded,
         bered,
     )
 
@@ -1304,7 +1325,9 @@ 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 +1364,7 @@ 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 +1395,7 @@ 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 +1627,14 @@ 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 +1650,7 @@ 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 +1675,7 @@ 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 +2002,7 @@ 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
@@ -2292,7 +2317,7 @@ class BitString(Obj):
                 offset=offset,
             )
         if t == self.tag:
-            if tag_only:
+            if tag_only:  # pragma: no cover
                 return
             return self._decode_chunk(lv, offset, decode_path, ctx)
         if t == self.tag_constructed:
@@ -2303,7 +2328,7 @@ class BitString(Obj):
                     decode_path=decode_path,
                     offset=offset,
                 )
-            if tag_only:
+            if tag_only:  # pragma: no cover
                 return
             lenindef = False
             try:
@@ -2401,7 +2426,7 @@ 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 +2465,7 @@ 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 +2783,7 @@ 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 +2815,7 @@ 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)
@@ -2883,7 +2910,7 @@ class Null(Obj):
                 decode_path=decode_path,
                 offset=offset,
             )
-        if tag_only:
+        if tag_only:  # pragma: no cover
             return
         try:
             l, _, v = len_decode(lv)
@@ -2929,6 +2956,7 @@ 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
@@ -3133,7 +3161,7 @@ class ObjectIdentifier(Obj):
                 decode_path=decode_path,
                 offset=offset,
             )
-        if tag_only:
+        if tag_only:  # pragma: no cover
             return
         try:
             l, llen, v = len_decode(lv)
@@ -3220,6 +3248,7 @@ 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 +3474,8 @@ 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 +3678,8 @@ 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 +3878,13 @@ 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
@@ -3944,7 +3984,7 @@ class Choice(Obj):
                 decode_path=decode_path,
                 offset=offset,
             )
-        if tag_only:
+        if tag_only:  # pragma: no cover
             return
         value, tail = spec.decode(
             tlv,
@@ -3984,6 +4024,7 @@ 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 +4113,14 @@ 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 +4255,7 @@ 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:
@@ -4338,18 +4388,14 @@ class Sequence(Obj):
 
     All defaulted values are always optional.
 
-    .. _strict_default_existence_ctx:
-
-    .. warning::
+    .. _allow_default_values_ctx:
 
-       When decoded DER contains defaulted value inside, then
-       technically this is not valid DER encoding. But we allow and pass
-       it **by default**. Of course reencoding of that kind of DER will
-       result in different binary representation (validly without
-       defaulted value inside). You can enable strict defaulted values
-       existence validation by setting ``"strict_default_existence":
-       True`` :ref:`context <ctx>` option -- decoding process will raise
-       an exception if defaulted value is met.
+    DER prohibits default value encoding and will raise an error if
+    default value is unexpectedly met during decode.
+    If :ref:`bered <bered_ctx>` context option is set, then no error
+    will be raised, but ``bered`` attribute set. You can disable strict
+    defaulted values existence validation by setting
+    ``"allow_default_values": True`` :ref:`context <ctx>` option.
 
     Two sequences are equal if they have equal specification (schema),
     implicit/explicit tagging and the same values.
@@ -4407,6 +4453,12 @@ 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
@@ -4506,13 +4558,14 @@ class Sequence(Obj):
                 decode_path=decode_path,
                 offset=offset,
             )
-        if tag_only:
+        if tag_only:  # pragma: no cover
             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__,
@@ -4540,6 +4593,8 @@ class Sequence(Obj):
         vlen = 0
         sub_offset = offset + tlen + llen
         values = {}
+        ber_encoded = False
+        ctx_allow_default_values = ctx.get("allow_default_values", False)
         for name, spec in self.specs.items():
             if spec.optional and (
                     (lenindef and v[:EOC_LEN].tobytes() == EOC) or
@@ -4612,15 +4667,15 @@ class Sequence(Obj):
             sub_offset += value_len
             v = v_tail
             if spec.default is not None and value == spec.default:
-                if ctx.get("strict_default_existence", False):
+                if ctx_bered or ctx_allow_default_values:
+                    ber_encoded = True
+                else:
                     raise DecodeError(
                         "DEFAULT value met",
                         klass=self.__class__,
                         decode_path=sub_decode_path,
                         offset=sub_offset,
                     )
-                else:
-                    continue
             values[name] = value
 
             spec_defines = getattr(spec, "defines", ())
@@ -4663,6 +4718,7 @@ class Sequence(Obj):
         )
         obj._value = values
         obj.lenindef = lenindef
+        obj.ber_encoded = ber_encoded
         return obj, tail
 
     def __repr__(self):
@@ -4694,6 +4750,8 @@ 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 +4766,14 @@ 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)
@@ -4738,10 +4804,11 @@ class Set(Sequence):
         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__,
@@ -4768,6 +4835,10 @@ class Set(Sequence):
         vlen = 0
         sub_offset = offset + tlen + llen
         values = {}
+        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:
@@ -4800,12 +4871,32 @@ class Set(Sequence):
                 ctx=ctx,
             )
             value_len = value.fulllen
+            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:
+                ber_encoded = True
+            else:
+                raise DecodeError(
+                    "DEFAULT value met",
+                    klass=self.__class__,
+                    decode_path=sub_decode_path,
+                    offset=sub_offset,
+                )
+            values[name] = value
+            value_prev = v[:value_len]
             sub_offset += value_len
             vlen += value_len
             v = v_tail
-            if spec.default is None or value != spec.default:  # pragma: no cover
-                # SeqMixing.test_encoded_default_accepted covers that place
-                values[name] = value
         obj = self.__class__(
             schema=self.specs,
             impl=self.tag,
@@ -4814,7 +4905,6 @@ class Set(Sequence):
             optional=self.optional,
             _decoded=(offset, llen, vlen + (EOC_LEN if lenindef else 0)),
         )
-        obj._value = values
         if lenindef:
             if v[:EOC_LEN].tobytes() != EOC:
                 raise DecodeError(
@@ -4825,6 +4915,7 @@ class Set(Sequence):
                 )
             tail = v[EOC_LEN:]
             obj.lenindef = True
+        obj._value = values
         if not obj.ready:
             raise DecodeError(
                 "not all values are ready",
@@ -4832,6 +4923,7 @@ class Set(Sequence):
                 decode_path=decode_path,
                 offset=offset,
             )
+        obj.ber_encoded = ber_encoded
         return obj, tail
 
 
@@ -4930,6 +5022,12 @@ 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
@@ -5015,7 +5113,7 @@ 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:
@@ -5034,10 +5132,11 @@ 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__,
@@ -5065,22 +5164,38 @@ 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,
@@ -5109,6 +5224,7 @@ class SequenceOf(Obj):
                 )
             obj.lenindef = True
             tail = v[EOC_LEN:]
+        obj.ber_encoded = ber_encoded
         return obj, tail
 
     def __repr__(self):
@@ -5136,6 +5252,8 @@ 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),))
@@ -5158,6 +5276,16 @@ 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