commit 77310c9cb96c0367412afbc6535ea54fe25fc442 Author: Dave Rolek <dmr-x@riseup.net> Date: Tue Aug 7 21:45:26 2018 +0000 Add CANNOT_DIRECTLY_UNPACK facility; set True for existing RelayCell Since RELAY cells come across the wire encrypted, they cannot be directly unpacked - their payload must first be decrypted. Note that this breaks unpacking RelayCell in the interim. --- stem/client/cell.py | 5 +++-- test/unit/client/cell.py | 2 ++ 2 files changed, 5 insertions(+), 2 deletions(-) diff --git a/stem/client/cell.py b/stem/client/cell.py index a4fb1a67..dcebc544 100644 --- a/stem/client/cell.py +++ b/stem/client/cell.py @@ -109,7 +109,7 @@ class Cell(object): """ for _, cls in inspect.getmembers(sys.modules[__name__]): - if name == getattr(cls, 'NAME', UNDEFINED): + if name == getattr(cls, 'NAME', UNDEFINED) and not getattr(cls, 'CANNOT_DIRECTLY_UNPACK', False): return cls raise ValueError("'%s' isn't a valid cell type" % name) @@ -125,7 +125,7 @@ class Cell(object): """ for _, cls in inspect.getmembers(sys.modules[__name__]): - if value == getattr(cls, 'VALUE', UNDEFINED): + if value == getattr(cls, 'VALUE', UNDEFINED) and not getattr(cls, 'CANNOT_DIRECTLY_UNPACK', False): return cls raise ValueError("'%s' isn't a valid cell value" % value) @@ -371,6 +371,7 @@ class RelayCell(CircuitCell): NAME = 'RELAY' VALUE = 3 IS_FIXED_SIZE = True + CANNOT_DIRECTLY_UNPACK = True def __init__(self, circ_id, command, data, digest = 0, stream_id = 0, recognized = 0, unused = b''): if 'HASH' in str(type(digest)): diff --git a/test/unit/client/cell.py b/test/unit/client/cell.py index a6ddf3ea..b8fe58df 100644 --- a/test/unit/client/cell.py +++ b/test/unit/client/cell.py @@ -220,6 +220,8 @@ class TestCell(unittest.TestCase): self.assertRaisesWith(ValueError, expected_message_format % payload_len, BaseRelayCell, arbitrary_circ_id, ZERO * payload_len) def test_relay_cell(self): + self.assertEquals(True, RelayCell.CANNOT_DIRECTLY_UNPACK) + for cell_bytes, (command, command_int, circ_id, stream_id, data, digest, unused, link_protocol) in RELAY_CELLS.items(): if not unused.strip(ZERO): self.assertEqual(cell_bytes, RelayCell(circ_id, command, data, digest, stream_id).pack(link_protocol))