From 863d21e01e95ba9f1626159b6997c794e0cc11a5 Mon Sep 17 00:00:00 2001 From: Sergey Matveev Date: Sat, 8 Dec 2018 19:05:10 +0300 Subject: [PATCH] ctx is safe to use as immutable --- VERSION | 2 +- doc/news.rst | 7 +++++ pyderasn.py | 17 ++++++++++ tests/test_pyderasn.py | 71 ++++++++++++++++++++++++++++++++++++++---- 4 files changed, 90 insertions(+), 7 deletions(-) diff --git a/VERSION b/VERSION index 515be8f..4caecc7 100644 --- a/VERSION +++ b/VERSION @@ -1 +1 @@ -4.4 +4.5 diff --git a/doc/news.rst b/doc/news.rst index 369b823..87863f5 100644 --- a/doc/news.rst +++ b/doc/news.rst @@ -1,6 +1,13 @@ News ==== +.. _release4.5: + +4.5 +--- +* ``ctx`` parameter can be safely used in .decode() and won't be muted + + .. _release4.4: 4.4 diff --git a/pyderasn.py b/pyderasn.py index aa91b04..4142af6 100755 --- a/pyderasn.py +++ b/pyderasn.py @@ -539,6 +539,7 @@ from codecs import getdecoder from codecs import getencoder from collections import namedtuple from collections import OrderedDict +from copy import copy from datetime import datetime from math import ceil from os import environ @@ -646,6 +647,7 @@ LENINDEF_PP_CHAR = "I" if PY2 else "∞" class ASN1Error(ValueError): pass + class DecodeError(ASN1Error): def __init__(self, msg="", klass=None, decode_path=(), offset=0): """ @@ -1027,6 +1029,7 @@ class Obj(object): decode_path=(), ctx=None, tag_only=False, + _ctx_immutable=True, ): """Decode the data @@ -1038,10 +1041,13 @@ class Obj(object): :param tag_only: decode only the tag, without length and contents (used only in Choice and Set structures, trying to determine if tag satisfies the scheme) + :param _ctx_immutable: do we need to copy ``ctx`` before using it :returns: (Obj, remaining data) """ if ctx is None: ctx = {} + elif _ctx_immutable: + ctx = copy(ctx) tlv = memoryview(data) if self._expl is None: result = self._decode( @@ -2387,6 +2393,7 @@ class BitString(Obj): decode_path=sub_decode_path, leavemm=True, ctx=ctx, + _ctx_immutable=False, ) except TagMismatch: raise DecodeError( @@ -2751,6 +2758,7 @@ class OctetString(Obj): decode_path=sub_decode_path, leavemm=True, ctx=ctx, + _ctx_immutable=False, ) except TagMismatch: raise DecodeError( @@ -4007,6 +4015,7 @@ class Choice(Obj): decode_path=sub_decode_path, ctx=ctx, tag_only=True, + _ctx_immutable=False, ) except TagMismatch: continue @@ -4025,6 +4034,7 @@ class Choice(Obj): leavemm=True, decode_path=sub_decode_path, ctx=ctx, + _ctx_immutable=False, ) obj = self.__class__( schema=self.specs, @@ -4226,6 +4236,7 @@ class Any(Obj): decode_path=decode_path + (str(chunk_i),), leavemm=True, ctx=ctx, + _ctx_immutable=False, ) vlen += chunk.tlvlen sub_offset += chunk.tlvlen @@ -4641,6 +4652,7 @@ class Sequence(Obj): leavemm=True, decode_path=sub_decode_path, ctx=ctx, + _ctx_immutable=False, ) except TagMismatch: if spec.optional: @@ -4665,6 +4677,7 @@ class Sequence(Obj): leavemm=True, decode_path=sub_sub_decode_path, ctx=ctx, + _ctx_immutable=False, ) if len(defined_tail) > 0: raise DecodeError( @@ -4684,6 +4697,7 @@ class Sequence(Obj): leavemm=True, decode_path=sub_decode_path + (DecodePathDefBy(defined_by),), ctx=ctx, + _ctx_immutable=False, ) if len(defined_tail) > 0: raise DecodeError( @@ -4885,6 +4899,7 @@ class Set(Sequence): decode_path=sub_decode_path, ctx=ctx, tag_only=True, + _ctx_immutable=False, ) except TagMismatch: continue @@ -4901,6 +4916,7 @@ class Set(Sequence): leavemm=True, decode_path=sub_decode_path, ctx=ctx, + _ctx_immutable=False, ) value_len = value.fulllen if value_prev.tobytes() > v[:value_len].tobytes(): @@ -5210,6 +5226,7 @@ class SequenceOf(Obj): leavemm=True, decode_path=sub_decode_path, ctx=ctx, + _ctx_immutable=False, ) value_len = value.fulllen if ordering_check: diff --git a/tests/test_pyderasn.py b/tests/test_pyderasn.py index 26addf0..a0a60cb 100644 --- a/tests/test_pyderasn.py +++ b/tests/test_pyderasn.py @@ -16,6 +16,7 @@ # License along with this program. If not, see # . +from copy import deepcopy from datetime import datetime from string import ascii_letters from string import digits @@ -132,6 +133,7 @@ tag_forms = sampled_from((TagFormConstructed, TagFormPrimitive)) decode_path_strat = lists(integers(), max_size=3).map( lambda decode_path: tuple(str(dp) for dp in decode_path) ) +ctx_dummy = dictionaries(integers(), integers(), min_size=2, max_size=4).example() class TestHex(TestCase): @@ -561,10 +563,13 @@ class TestBoolean(CommonMixin, TestCase): list(obj_expled.pps()) pprint(obj_expled, big_blobs=True, with_decode_path=True) obj_expled_encoded = obj_expled.encode() + ctx_copied = deepcopy(ctx_dummy) obj_decoded, tail = obj_expled.decode( obj_expled_encoded + tail_junk, offset=offset, + ctx=ctx_copied, ) + self.assertDictEqual(ctx_copied, ctx_dummy) repr(obj_decoded) list(obj_decoded.pps()) pprint(obj_decoded, big_blobs=True, with_decode_path=True) @@ -1041,10 +1046,13 @@ class TestInteger(CommonMixin, TestCase): list(obj_expled.pps()) pprint(obj_expled, big_blobs=True, with_decode_path=True) obj_expled_encoded = obj_expled.encode() + ctx_copied = deepcopy(ctx_dummy) obj_decoded, tail = obj_expled.decode( obj_expled_encoded + tail_junk, offset=offset, + ctx=ctx_copied, ) + self.assertDictEqual(ctx_copied, ctx_dummy) repr(obj_decoded) list(obj_decoded.pps()) pprint(obj_decoded, big_blobs=True, with_decode_path=True) @@ -1424,10 +1432,13 @@ class TestBitString(CommonMixin, TestCase): list(obj_expled.pps()) pprint(obj_expled, big_blobs=True, with_decode_path=True) obj_expled_encoded = obj_expled.encode() + ctx_copied = deepcopy(ctx_dummy) obj_decoded, tail = obj_expled.decode( obj_expled_encoded + tail_junk, offset=offset, + ctx=ctx_copied, ) + self.assertDictEqual(ctx_copied, ctx_dummy) repr(obj_decoded) list(obj_decoded.pps()) pprint(obj_decoded, big_blobs=True, with_decode_path=True) @@ -2002,10 +2013,13 @@ class TestOctetString(CommonMixin, TestCase): list(obj_expled.pps()) pprint(obj_expled, big_blobs=True, with_decode_path=True) obj_expled_encoded = obj_expled.encode() + ctx_copied = deepcopy(ctx_dummy) obj_decoded, tail = obj_expled.decode( obj_expled_encoded + tail_junk, offset=offset, + ctx=ctx_copied, ) + self.assertDictEqual(ctx_copied, ctx_dummy) repr(obj_decoded) list(obj_decoded.pps()) pprint(obj_decoded, big_blobs=True, with_decode_path=True) @@ -2299,10 +2313,13 @@ class TestNull(CommonMixin, TestCase): list(obj_expled.pps()) pprint(obj_expled, big_blobs=True, with_decode_path=True) obj_expled_encoded = obj_expled.encode() + ctx_copied = deepcopy(ctx_dummy) obj_decoded, tail = obj_expled.decode( obj_expled_encoded + tail_junk, offset=offset, + ctx=ctx_copied, ) + self.assertDictEqual(ctx_copied, ctx_dummy) repr(obj_decoded) list(obj_decoded.pps()) pprint(obj_decoded, big_blobs=True, with_decode_path=True) @@ -2631,10 +2648,13 @@ class TestObjectIdentifier(CommonMixin, TestCase): list(obj_expled.pps()) pprint(obj_expled, big_blobs=True, with_decode_path=True) obj_expled_encoded = obj_expled.encode() + ctx_copied = deepcopy(ctx_dummy) obj_decoded, tail = obj_expled.decode( obj_expled_encoded + tail_junk, offset=offset, + ctx=ctx_copied, ) + self.assertDictEqual(ctx_copied, ctx_dummy) repr(obj_decoded) list(obj_decoded.pps()) pprint(obj_decoded, big_blobs=True, with_decode_path=True) @@ -2922,10 +2942,13 @@ class TestEnumerated(CommonMixin, TestCase): list(obj_expled.pps()) pprint(obj_expled, big_blobs=True, with_decode_path=True) obj_expled_encoded = obj_expled.encode() + ctx_copied = deepcopy(ctx_dummy) obj_decoded, tail = obj_expled.decode( obj_expled_encoded + tail_junk, offset=offset, + ctx=ctx_copied, ) + self.assertDictEqual(ctx_copied, ctx_dummy) repr(obj_decoded) list(obj_decoded.pps()) pprint(obj_decoded, big_blobs=True, with_decode_path=True) @@ -3247,10 +3270,13 @@ class StringMixin(object): list(obj_expled.pps()) pprint(obj_expled, big_blobs=True, with_decode_path=True) obj_expled_encoded = obj_expled.encode() + ctx_copied = deepcopy(ctx_dummy) obj_decoded, tail = obj_expled.decode( obj_expled_encoded + tail_junk, offset=offset, + ctx=ctx_copied, ) + self.assertDictEqual(ctx_copied, ctx_dummy) repr(obj_decoded) list(obj_decoded.pps()) pprint(obj_decoded, big_blobs=True, with_decode_path=True) @@ -3673,10 +3699,13 @@ class TimeMixin(object): list(obj_expled.pps()) pprint(obj_expled, big_blobs=True, with_decode_path=True) obj_expled_encoded = obj_expled.encode() + ctx_copied = deepcopy(ctx_dummy) obj_decoded, tail = obj_expled.decode( obj_expled_encoded + tail_junk, offset=offset, + ctx=ctx_copied, ) + self.assertDictEqual(ctx_copied, ctx_dummy) repr(obj_decoded) list(obj_decoded.pps()) pprint(obj_decoded, big_blobs=True, with_decode_path=True) @@ -4060,10 +4089,13 @@ class TestAny(CommonMixin, TestCase): list(obj_expled.pps()) pprint(obj_expled, big_blobs=True, with_decode_path=True) obj_expled_encoded = obj_expled.encode() + ctx_copied = deepcopy(ctx_dummy) obj_decoded, tail = obj_expled.decode( obj_expled_encoded + tail_junk, offset=offset, + ctx=ctx_copied, ) + self.assertDictEqual(ctx_copied, ctx_dummy) repr(obj_decoded) list(obj_decoded.pps()) pprint(obj_decoded, big_blobs=True, with_decode_path=True) @@ -4411,10 +4443,13 @@ class TestChoice(CommonMixin, TestCase): list(obj_expled.pps()) pprint(obj_expled, big_blobs=True, with_decode_path=True) obj_expled_encoded = obj_expled.encode() + ctx_copied = deepcopy(ctx_dummy) obj_decoded, tail = obj_expled.decode( obj_expled_encoded + tail_junk, offset=offset, + ctx=ctx_copied, ) + self.assertDictEqual(ctx_copied, ctx_dummy) repr(obj_decoded) list(obj_decoded.pps()) pprint(obj_decoded, big_blobs=True, with_decode_path=True) @@ -4922,10 +4957,14 @@ class SeqMixing(object): t, _, lv = tag_strip(seq_encoded) _, _, v = len_decode(lv) seq_encoded_lenindef = t + LENINDEF + v + EOC + ctx_copied = deepcopy(ctx_dummy) + ctx_copied["bered"] = True seq_decoded_lenindef, tail_lenindef = seq.decode( seq_encoded_lenindef + tail_junk, - ctx={"bered": True}, + ctx=ctx_copied, ) + del ctx_copied["bered"] + self.assertDictEqual(ctx_copied, ctx_dummy) self.assertTrue(seq_decoded_lenindef.lenindef) self.assertTrue(seq_decoded_lenindef.bered) with self.assertRaises(DecodeError): @@ -5575,10 +5614,13 @@ class SeqOfMixing(object): list(obj_expled.pps()) pprint(obj_expled, big_blobs=True, with_decode_path=True) obj_expled_encoded = obj_expled.encode() + ctx_copied = deepcopy(ctx_dummy) obj_decoded, tail = obj_expled.decode( obj_expled_encoded + tail_junk, offset=offset, + ctx=ctx_copied, ) + self.assertDictEqual(ctx_copied, ctx_dummy) repr(obj_decoded) list(obj_decoded.pps()) pprint(obj_decoded, big_blobs=True, with_decode_path=True) @@ -6044,7 +6086,12 @@ class TestDefinesByPath(TestCase): pprint(seq_sequenced, big_blobs=True, with_decode_path=True) defines_by_path = [] - seq_integered, _ = Seq().decode(seq_integered_raw) + ctx_copied = deepcopy(ctx_dummy) + seq_integered, _ = Seq().decode( + seq_integered_raw, + ctx=ctx_copied, + ) + self.assertDictEqual(ctx_copied, ctx_dummy) self.assertIsNone(seq_integered["value"].defined) defines_by_path.append( (("type",), ((("value",), { @@ -6052,10 +6099,13 @@ class TestDefinesByPath(TestCase): type_sequenced: SeqInner(), }),)) ) + ctx_copied["defines_by_path"] = defines_by_path seq_integered, _ = Seq().decode( seq_integered_raw, - ctx={"defines_by_path": defines_by_path}, + ctx=ctx_copied, ) + del ctx_copied["defines_by_path"] + self.assertDictEqual(ctx_copied, ctx_dummy) self.assertIsNotNone(seq_integered["value"].defined) self.assertEqual(seq_integered["value"].defined[0], type_integered) self.assertEqual(seq_integered["value"].defined[1], Integer(123)) @@ -6066,10 +6116,13 @@ class TestDefinesByPath(TestCase): list(seq_integered.pps()) pprint(seq_integered, big_blobs=True, with_decode_path=True) + ctx_copied["defines_by_path"] = defines_by_path seq_sequenced, _ = Seq().decode( seq_sequenced_raw, - ctx={"defines_by_path": defines_by_path}, + ctx=ctx_copied, ) + del ctx_copied["defines_by_path"] + self.assertDictEqual(ctx_copied, ctx_dummy) self.assertIsNotNone(seq_sequenced["value"].defined) self.assertEqual(seq_sequenced["value"].defined[0], type_sequenced) seq_inner = seq_sequenced["value"].defined[1] @@ -6082,10 +6135,13 @@ class TestDefinesByPath(TestCase): ("value", DecodePathDefBy(type_sequenced), "typeInner"), ((("valueInner",), {type_innered: Pairs()}),), )) + ctx_copied["defines_by_path"] = defines_by_path seq_sequenced, _ = Seq().decode( seq_sequenced_raw, - ctx={"defines_by_path": defines_by_path}, + ctx=ctx_copied, ) + del ctx_copied["defines_by_path"] + self.assertDictEqual(ctx_copied, ctx_dummy) self.assertIsNotNone(seq_sequenced["value"].defined) self.assertEqual(seq_sequenced["value"].defined[0], type_sequenced) seq_inner = seq_sequenced["value"].defined[1] @@ -6112,10 +6168,13 @@ class TestDefinesByPath(TestCase): type_octet_stringed: OctetString(), }),), )) + ctx_copied["defines_by_path"] = defines_by_path seq_sequenced, _ = Seq().decode( seq_sequenced_raw, - ctx={"defines_by_path": defines_by_path}, + ctx=ctx_copied, ) + del ctx_copied["defines_by_path"] + self.assertDictEqual(ctx_copied, ctx_dummy) self.assertIsNotNone(seq_sequenced["value"].defined) self.assertEqual(seq_sequenced["value"].defined[0], type_sequenced) seq_inner = seq_sequenced["value"].defined[1] -- 2.44.0