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.venv2/Lib/site-packages/pyasn1/codec/der/decoder.py

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+#
+# This file is part of pyasn1 software.
+#
+# Copyright (c) 2005-2020, Ilya Etingof <etingof@gmail.com>
+# License: https://pyasn1.readthedocs.io/en/latest/license.html
+#
+import warnings
+
+from pyasn1.codec.cer import decoder
+from pyasn1.type import univ
+
+__all__ = ['decode', 'StreamingDecoder']
+
+
+class BitStringPayloadDecoder(decoder.BitStringPayloadDecoder):
+    supportConstructedForm = False
+
+
+class OctetStringPayloadDecoder(decoder.OctetStringPayloadDecoder):
+    supportConstructedForm = False
+
+
+# TODO: prohibit non-canonical encoding
+RealPayloadDecoder = decoder.RealPayloadDecoder
+
+TAG_MAP = decoder.TAG_MAP.copy()
+TAG_MAP.update(
+    {univ.BitString.tagSet: BitStringPayloadDecoder(),
+     univ.OctetString.tagSet: OctetStringPayloadDecoder(),
+     univ.Real.tagSet: RealPayloadDecoder()}
+)
+
+TYPE_MAP = decoder.TYPE_MAP.copy()
+
+# Put in non-ambiguous types for faster codec lookup
+for typeDecoder in TAG_MAP.values():
+    if typeDecoder.protoComponent is not None:
+        typeId = typeDecoder.protoComponent.__class__.typeId
+        if typeId is not None and typeId not in TYPE_MAP:
+            TYPE_MAP[typeId] = typeDecoder
+
+
+class SingleItemDecoder(decoder.SingleItemDecoder):
+    __doc__ = decoder.SingleItemDecoder.__doc__
+
+    TAG_MAP = TAG_MAP
+    TYPE_MAP = TYPE_MAP
+
+    supportIndefLength = False
+
+
+class StreamingDecoder(decoder.StreamingDecoder):
+    __doc__ = decoder.StreamingDecoder.__doc__
+
+    SINGLE_ITEM_DECODER = SingleItemDecoder
+
+
+class Decoder(decoder.Decoder):
+    __doc__ = decoder.Decoder.__doc__
+
+    STREAMING_DECODER = StreamingDecoder
+
+
+#: Turns DER octet stream into an ASN.1 object.
+#:
+#: Takes DER octet-stream and decode it into an ASN.1 object
+#: (e.g. :py:class:`~pyasn1.type.base.PyAsn1Item` derivative) which
+#: may be a scalar or an arbitrary nested structure.
+#:
+#: Parameters
+#: ----------
+#: substrate: :py:class:`bytes`
+#:     DER octet-stream
+#:
+#: Keyword Args
+#: ------------
+#: asn1Spec: any pyasn1 type object e.g. :py:class:`~pyasn1.type.base.PyAsn1Item` derivative
+#:     A pyasn1 type object to act as a template guiding the decoder. Depending on the ASN.1 structure
+#:     being decoded, *asn1Spec* may or may not be required. Most common reason for
+#:     it to require is that ASN.1 structure is encoded in *IMPLICIT* tagging mode.
+#:
+#: Returns
+#: -------
+#: : :py:class:`tuple`
+#:     A tuple of pyasn1 object recovered from DER substrate (:py:class:`~pyasn1.type.base.PyAsn1Item` derivative)
+#:     and the unprocessed trailing portion of the *substrate* (may be empty)
+#:
+#: Raises
+#: ------
+#: ~pyasn1.error.PyAsn1Error, ~pyasn1.error.SubstrateUnderrunError
+#:     On decoding errors
+#:
+#: Examples
+#: --------
+#: Decode DER serialisation without ASN.1 schema
+#:
+#: .. code-block:: pycon
+#:
+#:    >>> s, _ = decode(b'0\t\x02\x01\x01\x02\x01\x02\x02\x01\x03')
+#:    >>> str(s)
+#:    SequenceOf:
+#:     1 2 3
+#:
+#: Decode DER serialisation with ASN.1 schema
+#:
+#: .. code-block:: pycon
+#:
+#:    >>> seq = SequenceOf(componentType=Integer())
+#:    >>> s, _ = decode(b'0\t\x02\x01\x01\x02\x01\x02\x02\x01\x03', asn1Spec=seq)
+#:    >>> str(s)
+#:    SequenceOf:
+#:     1 2 3
+#:
+decode = Decoder()
+
+def __getattr__(attr: str):
+    if newAttr := {"tagMap": "TAG_MAP", "typeMap": "TYPE_MAP"}.get(attr):
+        warnings.warn(f"{attr} is deprecated. Please use {newAttr} instead.", DeprecationWarning)
+        return globals()[newAttr]
+    raise AttributeError(attr)