def test_receive_data(self):
client_transport, _ = dummy_dtls_transport_pair()
client = RTCSctpTransport(client_transport)
client._last_received_tsn = 0
# receive chunk
chunk = DataChunk(flags=(SCTP_DATA_FIRST_FRAG | SCTP_DATA_LAST_FRAG))
chunk.user_data = b'foo'
chunk.tsn = 1
run(client._receive_chunk(chunk))
self.assertEqual(client._sack_needed, True)
self.assertEqual(client._sack_duplicates, [])
self.assertEqual(client._last_received_tsn, 1)
client._sack_needed = False
# receive chunk again
run(client._receive_chunk(chunk))
self.assertEqual(client._sack_needed, True)
self.assertEqual(client._sack_duplicates, [1])
self.assertEqual(client._last_received_tsn, 1)
def test_receive_data_out_of_order(self):
client_transport, _ = dummy_dtls_transport_pair()
client = RTCSctpTransport(client_transport)
client._last_received_tsn = 0
# build chunks
chunks = []
chunk = DataChunk(flags=SCTP_DATA_FIRST_FRAG)
chunk.user_data = b'foo'
chunk.tsn = 1
chunks.append(chunk)
chunk = DataChunk()
chunk.user_data = b'bar'
chunk.tsn = 2
chunks.append(chunk)
chunk = DataChunk(flags=SCTP_DATA_LAST_FRAG)
chunk.user_data = b'baz'
chunk.tsn = 3
chunks.append(chunk)
# receive first chunk
run(client._receive_chunk(chunks[0]))
self.assertEqual(client._sack_needed, True)
self.assertEqual(client._sack_duplicates, [])
self.assertEqual(client._sack_misordered, set())
self.assertEqual(client._last_received_tsn, 1)
client._sack_needed = False
# receive last chunk
run(client._receive_chunk(chunks[2]))
self.assertEqual(client._sack_needed, True)
self.assertEqual(client._sack_duplicates, [])
self.assertEqual(client._sack_misordered, set([3]))
self.assertEqual(client._last_received_tsn, 1)
client._sack_needed = False
# receive middle chunk
run(client._receive_chunk(chunks[1]))
self.assertEqual(client._sack_needed, True)
self.assertEqual(client._sack_duplicates, [])
self.assertEqual(client._sack_misordered, set([]))
self.assertEqual(client._last_received_tsn, 3)
client._sack_needed = False
# receive last chunk again
run(client._receive_chunk(chunks[2]))
self.assertEqual(client._sack_needed, True)
self.assertEqual(client._sack_duplicates, [3])
self.assertEqual(client._sack_misordered, set([]))
self.assertEqual(client._last_received_tsn, 3)
client._sack_needed = False
def setUp(self):
self.fragmented = []
self.whole = []
# fragmented
chunk = DataChunk(flags=SCTP_DATA_FIRST_FRAG)
chunk.tsn = 1
chunk.protocol = 123
chunk.stream_id = 456
chunk.user_data = b'foo'
self.fragmented.append(chunk)
chunk = DataChunk()
chunk.protocol = 123
chunk.stream_id = 456
chunk.tsn = 2
chunk.user_data = b'bar'
self.fragmented.append(chunk)
chunk = DataChunk(flags=SCTP_DATA_LAST_FRAG)
chunk.protocol = 123
chunk.stream_id = 456
chunk.tsn = 3
chunk.user_data = b'baz'
self.fragmented.append(chunk)
# whole
chunk = DataChunk(flags=SCTP_DATA_FIRST_FRAG | SCTP_DATA_LAST_FRAG)
chunk.tsn = 1
chunk.protocol = 123
chunk.stream_id = 456
chunk.stream_seq = 0
chunk.user_data = b'foo'
self.whole.append(chunk)
chunk = DataChunk(flags=SCTP_DATA_FIRST_FRAG | SCTP_DATA_LAST_FRAG)
chunk.tsn = 2
chunk.protocol = 123
chunk.stream_id = 456
chunk.stream_seq = 1
chunk.user_data = b'bar'
self.whole.append(chunk)
chunk = DataChunk(flags=SCTP_DATA_FIRST_FRAG)
chunk.tsn = 3
chunk.protocol = 123
chunk.stream_id = 456
chunk.stream_seq = 2
chunk.user_data = b'baz'
self.whole.append(chunk)