X-Git-Url: http://www.git.cypherpunks.ru/?p=pyderasn.git;a=blobdiff_plain;f=pyderasn.py;h=acf0e469260588a921f20d5493546a86955e2a2b;hp=717c06cce42d63a15ed38356f71eb92cce217076;hb=4d56972efc2c9afe2edb27c4d91bf5c1d5ca4ede;hpb=63f01edc8b8f09f07fcc331f92242bbca1db40b7

diff --git a/pyderasn.py b/pyderasn.py
index 717c06c..acf0e46 100755
--- a/pyderasn.py
+++ b/pyderasn.py
@@ -68,7 +68,7 @@ ____
 Most types in ASN.1 has specific tag for them. ``Obj.tag_default`` is
 the default tag used during coding process. You can override it with
 either ``IMPLICIT`` (using ``impl`` keyword argument), or
-``EXPLICIT`` one (using ``expl`` keyword argument). Both arguments takes
+``EXPLICIT`` one (using ``expl`` keyword argument). Both arguments take
 raw binary string, containing that tag. You can **not** set implicit and
 explicit tags simultaneously.
 
@@ -88,10 +88,10 @@ number. Pay attention that explicit tags always have *constructed* tag
 
 Implicit tag is not explicitly shown.
 
-Two object of the same type, but with different implicit/explicit tags
+Two objects of the same type, but with different implicit/explicit tags
 are **not** equal.
 
-You can get objects effective tag (either default or implicited) through
+You can get object's effective tag (either default or implicited) through
 ``tag`` property. You can decode it using :py:func:`pyderasn.tag_decode`
 function::
 
@@ -159,12 +159,12 @@ raised.
 Common methods
 ______________
 
-All objects have ``ready`` boolean property, that tells if it is ready
-to be encoded. If that kind of action is performed on unready object,
-then :py:exc:`pyderasn.ObjNotReady` exception will be raised.
+All objects have ``ready`` boolean property, that tells if object is
+ready to be encoded. If that kind of action is performed on unready
+object, then :py:exc:`pyderasn.ObjNotReady` exception will be raised.
 
-All objects have ``copy()`` method, returning its copy, that can be safely
-mutated.
+All objects have ``copy()`` method, that returns their copy, that can be
+safely mutated.
 
 .. _decoding:
 
@@ -251,16 +251,19 @@ done.
 Following types can be automatically decoded (DEFINED BY):
 
 * :py:class:`pyderasn.Any`
+* :py:class:`pyderasn.BitString` (that is multiple of 8 bits)
 * :py:class:`pyderasn.OctetString`
 * :py:class:`pyderasn.SequenceOf`/:py:class:`pyderasn.SetOf`
   ``Any``/``OctetString``-s
 
 When any of those fields is automatically decoded, then ``.defined``
-attribute contains ``(OID, value)`` tuple. OID tell by which OID it was
-defined, ``value`` contains corresponding decoded value. For example
+attribute contains ``(OID, value)`` tuple. ``OID`` tells by which OID it
+was defined, ``value`` contains corresponding decoded value. For example
 above, ``content_info["content"].defined == (id_signedData,
 signed_data)``.
 
+.. _defines_by_path_kwarg:
+
 defines_by_path kwarg
 _____________________
 
@@ -322,8 +325,8 @@ of ``PKIResponse``::
 
 Pay attention for :py:func:`pyderasn.decode_path_defby` and ``any``.
 First function is useful for path construction when some automatic
-decoding is already done. ``any`` is used for human readability and
-means literally any value it meet -- useful for sequence and set of-s.
+decoding is already done. ``any`` means literally any value it meet --
+useful for SEQUENCE/SET OF-s.
 
 Primitive types
 ---------------
@@ -1679,7 +1682,7 @@ class BitString(Obj):
     >>> b.specs
     {'nonRepudiation': 1, 'digitalSignature': 0, 'keyEncipherment': 2}
     """
-    __slots__ = ("specs",)
+    __slots__ = ("specs", "defined")
     tag_default = tag_encode(3)
     asn1_type_name = "BIT STRING"
 
@@ -1716,6 +1719,7 @@ class BitString(Obj):
             )
             if value is None:
                 self._value = default
+        self.defined = None
 
     def _bits2octets(self, bits):
         if len(self.specs) > 0:
@@ -1964,6 +1968,11 @@ class BitString(Obj):
             expl_llen=self.expl_llen if self.expled else None,
             expl_vlen=self.expl_vlen if self.expled else None,
         )
+        defined_by, defined = self.defined or (None, None)
+        if defined_by is not None:
+            yield defined.pps(
+                decode_path=decode_path + (decode_path_defby(defined_by),)
+            )
 
 
 class OctetString(Obj):
@@ -4326,6 +4335,12 @@ def generic_decoder():  # pragma: no cover
 def main():  # pragma: no cover
     import argparse
     parser = argparse.ArgumentParser(description="PyDERASN ASN.1 DER decoder")
+    parser.add_argument(
+        "--skip",
+        type=int,
+        default=0,
+        help="Skip that number of bytes from the beginning",
+    )
     parser.add_argument(
         "--oids",
         help="Python path to dictionary with OIDs",
@@ -4334,12 +4349,17 @@ def main():  # pragma: no cover
         "--schema",
         help="Python path to schema definition to use",
     )
+    parser.add_argument(
+        "--defines-by-path",
+        help="Python path to decoder's defines_by_path",
+    )
     parser.add_argument(
         "DERFile",
         type=argparse.FileType("rb"),
         help="Path to DER file you want to decode",
     )
     args = parser.parse_args()
+    args.DERFile.seek(args.skip)
     der = memoryview(args.DERFile.read())
     args.DERFile.close()
     oids = obj_by_path(args.oids) if args.oids else {}
@@ -4349,7 +4369,13 @@ def main():  # pragma: no cover
         pprinter = partial(pprint, big_blobs=True)
     else:
         schema, pprinter = generic_decoder()
-    obj, tail = schema().decode(der)
+    obj, tail = schema().decode(
+        der,
+        defines_by_path=(
+            None if args.defines_by_path is None
+            else obj_by_path(args.defines_by_path)
+        ),
+    )
     print(pprinter(obj, oids=oids))
     if tail != b"":
         print("\nTrailing data: %s" % hexenc(tail))