X-Git-Url: http://www.git.cypherpunks.ru/?p=pyderasn.git;a=blobdiff_plain;f=pyderasn.py;h=3eb10715ed1400a0bd3c55dccd71419a46e7c499;hp=116ef6e9e8d899fb2dfa95e431b6915045993c4c;hb=HEAD;hpb=b54295efb44566cd7eb6b09a4d5366f82cb96441 diff --git a/pyderasn.py b/pyderasn.py index 116ef6e..54242a3 100755 --- a/pyderasn.py +++ b/pyderasn.py @@ -4,7 +4,7 @@ # pylint: disable=line-too-long,superfluous-parens,protected-access,too-many-lines # pylint: disable=too-many-return-statements,too-many-branches,too-many-statements # PyDERASN -- Python ASN.1 DER/CER/BER codec with abstract structures -# Copyright (C) 2017-2022 Sergey Matveev +# Copyright (C) 2017-2024 Sergey Matveev # # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU Lesser General Public License as @@ -235,6 +235,7 @@ Currently available context options: * :ref:`bered ` * :ref:`defines_by_path ` * :ref:`evgen_mode_upto ` +* :ref:`keep_memoryview ` .. _pprinting: @@ -706,6 +707,15 @@ creates read-only memoryview on the file contents:: page cache used for mmaps. It can take twice the necessary size in the memory: both in page cache and ZFS ARC. +.. _keep_memoryview_ctx: + +That read-only memoryview could be safe to be used as a value inside +decoded :py:class:`pyderasn.OctetString` and :py:class:`pyderasn.Any` +objects. You can enable that by setting `"keep_memoryview": True` in +:ref:`decode context `. No OCTET STRING and ANY values will be +copied to memory. Of course that works only in DER encoding, where the +value is continuously encoded. + CER encoding ____________ @@ -1186,7 +1196,7 @@ except ImportError: # pragma: no cover tzUTC = "missing" -__version__ = "9.1" +__version__ = "9.3" __all__ = ( "agg_octet_string", @@ -3630,6 +3640,7 @@ class OctetString(Obj): tag_default = tag_encode(4) asn1_type_name = "OCTET STRING" evgen_mode_skip_value = True + memoryview_safe = True def __init__( self, @@ -3726,6 +3737,10 @@ class OctetString(Obj): self._assert_ready() return bytes(self._value) + def memoryview(self): + self._assert_ready() + return memoryview(self._value) + def __eq__(self, their): if their.__class__ == bytes: return self._value == their @@ -3839,12 +3854,15 @@ class OctetString(Obj): decode_path=decode_path, offset=offset, ) + if evgen_mode and self.evgen_mode_skip_value: + value = None + elif self.memoryview_safe and ctx.get("keep_memoryview", False): + value = v + else: + value = v.tobytes() try: obj = self.__class__( - value=( - None if (evgen_mode and self.evgen_mode_skip_value) - else v.tobytes() - ), + value=value, bounds=(self._bound_min, self._bound_max), impl=self.tag, expl=self._expl, @@ -4694,6 +4712,7 @@ class CommonString(OctetString): - utf-16-be """ __slots__ = () + memoryview_safe = False def _value_sanitize(self, value): value_raw = None @@ -4743,6 +4762,9 @@ class CommonString(OctetString): return self._value.decode(self.encoding) return str(self._value) + def memoryview(self): + raise ValueError("CommonString does not support .memoryview()") + def __repr__(self): return pp_console_row(next(self.pps())) @@ -5842,7 +5864,7 @@ class Any(Obj): value = self._value_sanitize(value) self._value = value if self._expl is None: - if value.__class__ == bytes: + if value.__class__ == bytes or value.__class__ == memoryview: tag_class, _, tag_num = tag_decode(tag_strip(value)[0]) else: tag_class, tag_num = value.tag_order @@ -5852,7 +5874,7 @@ class Any(Obj): self.defined = None def _value_sanitize(self, value): - if value.__class__ == bytes: + if value.__class__ == bytes or value.__class__ == memoryview: if len(value) == 0: raise ValueError("%s value can not be empty" % self.__class__.__name__) return value @@ -5903,13 +5925,13 @@ class Any(Obj): self.defined = state.defined def __eq__(self, their): - if their.__class__ == bytes: - if self._value.__class__ == bytes: + if their.__class__ == bytes or their.__class__ == memoryview: + if self._value.__class__ == bytes or their.__class__ == memoryview: return self._value == their return self._value.encode() == their if issubclass(their.__class__, Any): if self.ready and their.ready: - return bytes(self) == bytes(their) + return self.memoryview() == their.memoryview() return self.ready == their.ready return False @@ -5930,8 +5952,17 @@ class Any(Obj): value = self._value if value.__class__ == bytes: return value + if value.__class__ == memoryview: + return bytes(value) return self._value.encode() + def memoryview(self): + self._assert_ready() + value = self._value + if value.__class__ == memoryview: + return memoryview(value) + return memoryview(bytes(self)) + @property def tlen(self): return 0 @@ -5939,20 +5970,20 @@ class Any(Obj): def _encode(self): self._assert_ready() value = self._value - if value.__class__ == bytes: - return value + if value.__class__ == bytes or value.__class__ == memoryview: + return bytes(self) return value.encode() def _encode1st(self, state): self._assert_ready() value = self._value - if value.__class__ == bytes: + if value.__class__ == bytes or value.__class__ == memoryview: return len(value), state return value.encode1st(state) def _encode2nd(self, writer, state_iter): value = self._value - if value.__class__ == bytes: + if value.__class__ == bytes or value.__class__ == memoryview: write_full(writer, value) else: value.encode2nd(writer, state_iter) @@ -5960,7 +5991,7 @@ class Any(Obj): def _encode_cer(self, writer): self._assert_ready() value = self._value - if value.__class__ == bytes: + if value.__class__ == bytes or value.__class__ == memoryview: write_full(writer, value) else: value.encode_cer(writer) @@ -6027,8 +6058,14 @@ class Any(Obj): ) tlvlen = tlen + llen + l v, tail = tlv[:tlvlen], v[l:] + if evgen_mode: + value = None + elif ctx.get("keep_memoryview", False): + value = v + else: + value = v.tobytes() obj = self.__class__( - value=None if evgen_mode else v.tobytes(), + value=value, expl=self._expl, optional=self.optional, _decoded=(offset, 0, tlvlen), @@ -6043,7 +6080,7 @@ class Any(Obj): value = self._value if value is None: pass - elif value.__class__ == bytes: + elif value.__class__ == bytes or value.__class__ == memoryview: value = None else: value = repr(value) @@ -6053,7 +6090,10 @@ class Any(Obj): obj_name=self.__class__.__name__, decode_path=decode_path, value=value, - blob=self._value if self._value.__class__ == bytes else None, + blob=self._value if ( + self._value.__class__ == bytes or + value.__class__ == memoryview + ) else None, optional=self.optional, default=self == self.default, impl=None if self.tag == self.tag_default else tag_decode(self.tag),