From eb67733960022e82168120c03b5c0e81272ddb2b Mon Sep 17 00:00:00 2001 From: Sergey Matveev Date: Thu, 22 Mar 2018 16:02:00 +0300 Subject: [PATCH] Fix nasty BitString decode bug --- VERSION | 2 +- doc/news.rst | 8 +++ pyderasn.py | 2 +- tests/test_pyderasn.py | 115 +++++++++++++++++++++++++++++------------ 4 files changed, 92 insertions(+), 35 deletions(-) diff --git a/VERSION b/VERSION index a3ec5a4..eb39e53 100644 --- a/VERSION +++ b/VERSION @@ -1 +1 @@ -3.2 +3.3 diff --git a/doc/news.rst b/doc/news.rst index b9de7c1..ad0284c 100644 --- a/doc/news.rst +++ b/doc/news.rst @@ -1,6 +1,14 @@ News ==== +.. _release3.3: + +3.3 +--- +* Fix nasty BitString decoding bug: it could fail when data follows + encoded BitString value. There weren't any problems when BitString is + at the end of Sequence + .. _release3.2: 3.2 diff --git a/pyderasn.py b/pyderasn.py index 207920e..885f816 100755 --- a/pyderasn.py +++ b/pyderasn.py @@ -2014,7 +2014,7 @@ class BitString(Obj): decode_path=decode_path, offset=offset, ) - if byte2int(v[-1:]) & ((1 << pad_size) - 1) != 0: + if byte2int(v[l - 1:l]) & ((1 << pad_size) - 1) != 0: raise DecodeError( "invalid pad", klass=self.__class__, diff --git a/tests/test_pyderasn.py b/tests/test_pyderasn.py index 18ce656..f655d97 100644 --- a/tests/test_pyderasn.py +++ b/tests/test_pyderasn.py @@ -529,8 +529,9 @@ class TestBoolean(CommonMixin, TestCase): booleans(), integers(min_value=1).map(tag_ctxc), integers(min_value=0), + binary(max_size=5), ) - def test_symmetric(self, values, value, tag_expl, offset): + def test_symmetric(self, values, value, tag_expl, offset, tail_junk): for klass in (Boolean, BooleanInherited): _, _, _, default, optional, _decoded = values obj = klass( @@ -548,10 +549,13 @@ class TestBoolean(CommonMixin, TestCase): repr(obj_expled) pprint(obj_expled) obj_expled_encoded = obj_expled.encode() - obj_decoded, tail = obj_expled.decode(obj_expled_encoded, offset=offset) + obj_decoded, tail = obj_expled.decode( + obj_expled_encoded + tail_junk, + offset=offset, + ) repr(obj_decoded) pprint(obj_decoded) - self.assertEqual(tail, b"") + self.assertEqual(tail, tail_junk) self.assertEqual(obj_decoded, obj_expled) self.assertNotEqual(obj_decoded, obj) self.assertEqual(bool(obj_decoded), bool(obj_expled)) @@ -904,8 +908,9 @@ class TestInteger(CommonMixin, TestCase): integers(), integers(min_value=1).map(tag_ctxc), integers(min_value=0), + binary(max_size=5), ) - def test_symmetric(self, values, value, tag_expl, offset): + def test_symmetric(self, values, value, tag_expl, offset, tail_junk): for klass in (Integer, IntegerInherited): _, _, _, _, default, optional, _, _decoded = values obj = klass( @@ -923,10 +928,13 @@ class TestInteger(CommonMixin, TestCase): repr(obj_expled) pprint(obj_expled) obj_expled_encoded = obj_expled.encode() - obj_decoded, tail = obj_expled.decode(obj_expled_encoded, offset=offset) + obj_decoded, tail = obj_expled.decode( + obj_expled_encoded + tail_junk, + offset=offset, + ) repr(obj_decoded) pprint(obj_decoded) - self.assertEqual(tail, b"") + self.assertEqual(tail, tail_junk) self.assertEqual(obj_decoded, obj_expled) self.assertNotEqual(obj_decoded, obj) self.assertEqual(int(obj_decoded), int(obj_expled)) @@ -1279,6 +1287,7 @@ class TestBitString(CommonMixin, TestCase): optional, _decoded, ) = d.draw(bit_string_values_strategy(value_required=True)) + tail_junk = d.draw(binary(max_size=5)) tag_expl = tag_ctxc(d.draw(integers(min_value=1))) offset = d.draw(integers(min_value=0)) for klass in (BitString, BitStringInherited): @@ -1299,10 +1308,13 @@ class TestBitString(CommonMixin, TestCase): repr(obj_expled) pprint(obj_expled) obj_expled_encoded = obj_expled.encode() - obj_decoded, tail = obj_expled.decode(obj_expled_encoded, offset=offset) + obj_decoded, tail = obj_expled.decode( + obj_expled_encoded + tail_junk, + offset=offset, + ) repr(obj_decoded) pprint(obj_decoded) - self.assertEqual(tail, b"") + self.assertEqual(tail, tail_junk) self.assertEqual(obj_decoded, obj_expled) self.assertNotEqual(obj_decoded, obj) self.assertEqual(bytes(obj_decoded), bytes(obj_expled)) @@ -1637,8 +1649,9 @@ class TestOctetString(CommonMixin, TestCase): binary(), integers(min_value=1).map(tag_ctxc), integers(min_value=0), + binary(max_size=5), ) - def test_symmetric(self, values, value, tag_expl, offset): + def test_symmetric(self, values, value, tag_expl, offset, tail_junk): for klass in (OctetString, OctetStringInherited): _, _, _, _, default, optional, _decoded = values obj = klass( @@ -1656,10 +1669,13 @@ class TestOctetString(CommonMixin, TestCase): repr(obj_expled) pprint(obj_expled) obj_expled_encoded = obj_expled.encode() - obj_decoded, tail = obj_expled.decode(obj_expled_encoded, offset=offset) + obj_decoded, tail = obj_expled.decode( + obj_expled_encoded + tail_junk, + offset=offset, + ) repr(obj_decoded) pprint(obj_decoded) - self.assertEqual(tail, b"") + self.assertEqual(tail, tail_junk) self.assertEqual(obj_decoded, obj_expled) self.assertNotEqual(obj_decoded, obj) self.assertEqual(bytes(obj_decoded), bytes(obj_expled)) @@ -1816,8 +1832,9 @@ class TestNull(CommonMixin, TestCase): null_values_strategy(), integers(min_value=1).map(tag_ctxc), integers(min_value=0), + binary(max_size=5), ) - def test_symmetric(self, values, tag_expl, offset): + def test_symmetric(self, values, tag_expl, offset, tail_junk): for klass in (Null, NullInherited): _, _, optional, _decoded = values obj = klass(optional=optional, _decoded=_decoded) @@ -1830,10 +1847,13 @@ class TestNull(CommonMixin, TestCase): repr(obj_expled) pprint(obj_expled) obj_expled_encoded = obj_expled.encode() - obj_decoded, tail = obj_expled.decode(obj_expled_encoded, offset=offset) + obj_decoded, tail = obj_expled.decode( + obj_expled_encoded + tail_junk, + offset=offset, + ) repr(obj_decoded) pprint(obj_decoded) - self.assertEqual(tail, b"") + self.assertEqual(tail, tail_junk) self.assertEqual(obj_decoded, obj_expled) self.assertNotEqual(obj_decoded, obj) self.assertSequenceEqual(obj_decoded.encode(), obj_expled_encoded) @@ -2136,8 +2156,9 @@ class TestObjectIdentifier(CommonMixin, TestCase): oid_strategy(), integers(min_value=1).map(tag_ctxc), integers(min_value=0), + binary(max_size=5), ) - def test_symmetric(self, values, value, tag_expl, offset): + def test_symmetric(self, values, value, tag_expl, offset, tail_junk): for klass in (ObjectIdentifier, ObjectIdentifierInherited): _, _, _, default, optional, _decoded = values obj = klass( @@ -2155,10 +2176,13 @@ class TestObjectIdentifier(CommonMixin, TestCase): repr(obj_expled) pprint(obj_expled) obj_expled_encoded = obj_expled.encode() - obj_decoded, tail = obj_expled.decode(obj_expled_encoded, offset=offset) + obj_decoded, tail = obj_expled.decode( + obj_expled_encoded + tail_junk, + offset=offset, + ) repr(obj_decoded) pprint(obj_decoded) - self.assertEqual(tail, b"") + self.assertEqual(tail, tail_junk) self.assertEqual(obj_decoded, obj_expled) self.assertNotEqual(obj_decoded, obj) self.assertEqual(tuple(obj_decoded), tuple(obj_expled)) @@ -2413,6 +2437,7 @@ class TestEnumerated(CommonMixin, TestCase): tag_expl = d.draw(integers(min_value=1).map(tag_ctxc)) offset = d.draw(integers(min_value=0)) value = d.draw(sampled_from(sorted([v for _, v in schema_input]))) + tail_junk = d.draw(binary(max_size=5)) class E(Enumerated): schema = schema_input @@ -2431,10 +2456,13 @@ class TestEnumerated(CommonMixin, TestCase): repr(obj_expled) pprint(obj_expled) obj_expled_encoded = obj_expled.encode() - obj_decoded, tail = obj_expled.decode(obj_expled_encoded, offset=offset) + obj_decoded, tail = obj_expled.decode( + obj_expled_encoded + tail_junk, + offset=offset, + ) repr(obj_decoded) pprint(obj_decoded) - self.assertEqual(tail, b"") + self.assertEqual(tail, tail_junk) self.assertEqual(obj_decoded, obj_expled) self.assertNotEqual(obj_decoded, obj) self.assertEqual(int(obj_decoded), int(obj_expled)) @@ -2724,6 +2752,7 @@ class StringMixin(object): value = d.draw(text(alphabet=self.text_alphabet())) tag_expl = tag_ctxc(d.draw(integers(min_value=1))) offset = d.draw(integers(min_value=0)) + tail_junk = d.draw(binary(max_size=5)) _, _, _, _, default, optional, _decoded = values obj = self.base_klass( value=value, @@ -2740,10 +2769,13 @@ class StringMixin(object): repr(obj_expled) pprint(obj_expled) obj_expled_encoded = obj_expled.encode() - obj_decoded, tail = obj_expled.decode(obj_expled_encoded, offset=offset) + obj_decoded, tail = obj_expled.decode( + obj_expled_encoded + tail_junk, + offset=offset, + ) repr(obj_decoded) pprint(obj_decoded) - self.assertEqual(tail, b"") + self.assertEqual(tail, tail_junk) self.assertEqual(obj_decoded, obj_expled) self.assertNotEqual(obj_decoded, obj) self.assertEqual(bytes(obj_decoded), bytes(obj_expled)) @@ -3008,6 +3040,7 @@ class TimeMixin(object): )) tag_expl = tag_ctxc(d.draw(integers(min_value=1))) offset = d.draw(integers(min_value=0)) + tail_junk = d.draw(binary(max_size=5)) _, _, _, default, optional, _decoded = values obj = self.base_klass( value=value, @@ -3024,10 +3057,13 @@ class TimeMixin(object): repr(obj_expled) pprint(obj_expled) obj_expled_encoded = obj_expled.encode() - obj_decoded, tail = obj_expled.decode(obj_expled_encoded, offset=offset) + obj_decoded, tail = obj_expled.decode( + obj_expled_encoded + tail_junk, + offset=offset, + ) repr(obj_decoded) pprint(obj_decoded) - self.assertEqual(tail, b"") + self.assertEqual(tail, tail_junk) self.assertEqual(obj_decoded, obj_expled) self.assertEqual(obj_decoded.todatetime(), obj_expled.todatetime()) self.assertEqual(obj_decoded.todatetime(), obj.todatetime()) @@ -3326,8 +3362,9 @@ class TestAny(CommonMixin, TestCase): integers().map(lambda x: Integer(x).encode()), integers(min_value=1).map(tag_ctxc), integers(min_value=0), + binary(max_size=5), ) - def test_symmetric(self, values, value, tag_expl, offset): + def test_symmetric(self, values, value, tag_expl, offset, tail_junk): for klass in (Any, AnyInherited): _, _, optional, _decoded = values obj = klass(value=value, optional=optional, _decoded=_decoded) @@ -3340,10 +3377,13 @@ class TestAny(CommonMixin, TestCase): repr(obj_expled) pprint(obj_expled) obj_expled_encoded = obj_expled.encode() - obj_decoded, tail = obj_expled.decode(obj_expled_encoded, offset=offset) + obj_decoded, tail = obj_expled.decode( + obj_expled_encoded + tail_junk, + offset=offset, + ) repr(obj_decoded) pprint(obj_decoded) - self.assertEqual(tail, b"") + self.assertEqual(tail, tail_junk) self.assertEqual(obj_decoded, obj_expled) self.assertEqual(bytes(obj_decoded), bytes(obj_expled)) self.assertEqual(bytes(obj_decoded), bytes(obj)) @@ -3570,6 +3610,7 @@ class TestChoice(CommonMixin, TestCase): ) tag_expl = tag_ctxc(d.draw(integers(min_value=1))) offset = d.draw(integers(min_value=0)) + tail_junk = d.draw(binary(max_size=5)) class Wahl(self.base_klass): schema = _schema @@ -3588,10 +3629,13 @@ class TestChoice(CommonMixin, TestCase): repr(obj_expled) pprint(obj_expled) obj_expled_encoded = obj_expled.encode() - obj_decoded, tail = obj_expled.decode(obj_expled_encoded, offset=offset) + obj_decoded, tail = obj_expled.decode( + obj_expled_encoded + tail_junk, + offset=offset, + ) repr(obj_decoded) pprint(obj_decoded) - self.assertEqual(tail, b"") + self.assertEqual(tail, tail_junk) self.assertEqual(obj_decoded, obj_expled) self.assertEqual(obj_decoded.choice, obj_expled.choice) self.assertEqual(obj_decoded.value, obj_expled.value) @@ -4057,14 +4101,15 @@ class SeqMixing(object): @given(data_strategy()) def test_symmetric(self, d): seq, expects = d.draw(sequence_strategy(seq_klass=self.base_klass)) + tail_junk = d.draw(binary(max_size=5)) self.assertTrue(seq.ready) self.assertFalse(seq.decoded) self._assert_expects(seq, expects) repr(seq) pprint(seq) seq_encoded = seq.encode() - seq_decoded, tail = seq.decode(seq_encoded) - self.assertEqual(tail, b"") + seq_decoded, tail = seq.decode(seq_encoded + tail_junk) + self.assertEqual(tail, tail_junk) self.assertTrue(seq.ready) self._assert_expects(seq_decoded, expects) self.assertEqual(seq, seq_decoded) @@ -4592,8 +4637,9 @@ class SeqOfMixing(object): lists(integers().map(Integer)), integers(min_value=1).map(tag_ctxc), integers(min_value=0), + binary(max_size=5), ) - def test_symmetric(self, values, value, tag_expl, offset): + def test_symmetric(self, values, value, tag_expl, offset, tail_junk): _, _, _, _, _, default, optional, _decoded = values class SeqOf(self.base_klass): @@ -4613,10 +4659,13 @@ class SeqOfMixing(object): repr(obj_expled) pprint(obj_expled) obj_expled_encoded = obj_expled.encode() - obj_decoded, tail = obj_expled.decode(obj_expled_encoded, offset=offset) + obj_decoded, tail = obj_expled.decode( + obj_expled_encoded + tail_junk, + offset=offset, + ) repr(obj_decoded) pprint(obj_decoded) - self.assertEqual(tail, b"") + self.assertEqual(tail, tail_junk) self._test_symmetric_compare_objs(obj_decoded, obj_expled) self.assertSequenceEqual(obj_decoded.encode(), obj_expled_encoded) self.assertSequenceEqual(obj_decoded.expl_tag, tag_expl) -- 2.44.0