Problem with obfs2/obfs3 (Bad encapsulated packet length?)
Posted: Tue Jan 16, 2018 11:20 am
Followed the instructions here:
https://www.sparklabs.com/support/kb/ar ... viscosity/
(1) OpenVPN, TCP, port 443
(2) Verified working in a 'vanilla' connection in Viscosity (yay)
(3) Run the following on the server, also created firewall rule
(5) Connect
Client Log:
https://www.sparklabs.com/support/kb/ar ... viscosity/
(1) OpenVPN, TCP, port 443
(2) Verified working in a 'vanilla' connection in Viscosity (yay)
(3) Run the following on the server, also created firewall rule
obfsproxy --log-min-severity=debug --no-safe-logging obfs2 --dest=127.0.0.1:443 server 0.0.0.0:993(4) Duplicated the working vanilla connection in Viscosity, changed only the port to 993 and the obfuscation method to obfs2 in the UI
(5) Connect
Client Log:
2018-01-15 19:17:25: Attempting to establish TCP connection with [AF_INET]127.0.0.1:54844 [nonblock]obfs2proxy output:
2018-01-15 19:17:26: TCP connection established with [AF_INET]127.0.0.1:54844
2018-01-15 19:17:26: TCPv4_CLIENT link local: (not bound)
2018-01-15 19:17:26: TCPv4_CLIENT link remote: [AF_INET]127.0.0.1:54844
2018-01-15 19:17:26: WARNING: Bad encapsulated packet length from peer (18516), which must be > 0 and <= 1627 -- please ensure that --tun-mtu or --link-mtu is equal on both peers -- this condition could also indicate a possible active attack on the TCP link -- [Attempting restart...]
2018-01-15 19:17:26: Connection reset, restarting [0]
2018-01-15 19:17:26: SIGUSR1[soft,connection-reset] received, process restarting
2018-01-15 19:17:29,139 [DEBUG] fact_s_0x806f4f518: New connection from [REDACTED]:54959.
2018-01-15 19:17:29,139 [INFO] Starting factory <obfsproxy.network.network.StaticDestinationClientFactory instance at 0x806f82ef0>
2018-01-15 19:17:29,139 [DEBUG] fact_c_0x806f82ef0: Client factory started connecting.
2018-01-15 19:17:29,139 [DEBUG] conn_0x806f87d90: connectionMade (server): Setting it as downstream on our circuit.
2018-01-15 19:17:29,139 [DEBUG] circ_0x806f82cf8: Setting downstream connection (conn_0x806f87d90).
2018-01-15 19:17:29,140 [DEBUG] conn_0x806f87d90: Incomplete circuit; cached 1448 bytes.
2018-01-15 19:17:29,140 [DEBUG] conn_0x806f87e90: connectionMade (server): Setting it as upstream on our circuit.
2018-01-15 19:17:29,140 [DEBUG] circ_0x806f82cf8: Setting upstream connection (conn_0x806f87e90).
2018-01-15 19:17:29,140 [DEBUG] circ_0x806f82cf8: Circuit completed.
2018-01-15 19:17:29,140 [DEBUG] obfs2 handshake: responder queued 7959 bytes (padding_length: 7935).
2018-01-15 19:17:29,141 [DEBUG] conn_0x806f87d90: Writing 7959 bytes.
2018-01-15 19:17:29,141 [DEBUG] circ_0x806f82cf8: downstream: Received 4344 bytes.
2018-01-15 19:17:29,141 [DEBUG] obfs2 receivedDownstream: Waiting for key.
2018-01-15 19:17:29,141 [DEBUG] obfs2 receivedDownstream: Got 4320 bytes of handshake data (padding_length: 4469, magic: 0x2bf5ca7e)
2018-01-15 19:17:29,141 [DEBUG] obfs2 receivedDownstream: Consumed 4320 bytes of padding, 149 still to come (0).
2018-01-15 19:17:29,141 [DEBUG] circ_0x806f82cf8: downstream: Received 149 bytes.
2018-01-15 19:17:29,142 [DEBUG] obfs2 receivedDownstream: Consumed 149 bytes of padding, 0 still to come (0).
2018-01-15 19:17:29,142 [DEBUG] obfs2 receivedDownstream: Processing 0 bytes of application data.
2018-01-15 19:17:29,142 [DEBUG] conn_0x806f87e90: Writing 0 bytes.
2018-01-15 19:17:29,146 [DEBUG] circ_0x806f82cf8: downstream: Received 56 bytes.
2018-01-15 19:17:29,146 [DEBUG] obfs2 receivedDownstream: Processing 56 bytes of application data.
2018-01-15 19:17:29,146 [DEBUG] conn_0x806f87e90: Writing 56 bytes.
2018-01-15 19:17:29,147 [DEBUG] circ_0x806f82cf8: upstream: Received 311 bytes.
2018-01-15 19:17:29,147 [DEBUG] obfs2 receivedUpstream: Transmitting 311 bytes.
2018-01-15 19:17:29,147 [DEBUG] conn_0x806f87d90: Writing 311 bytes.
2018-01-15 19:17:29,147 [DEBUG] conn_0x806f87e90: Connection was lost (Connection was closed cleanly.).
2018-01-15 19:17:29,147 [DEBUG] conn_0x806f87e90: Closing connection.
2018-01-15 19:17:29,147 [DEBUG] circ_0x806f82cf8: Tearing down circuit.
2018-01-15 19:17:29,147 [DEBUG] conn_0x806f87d90: Closing connection.
2018-01-15 19:17:29,148 [INFO] Stopping factory <obfsproxy.network.network.StaticDestinationClientFactory instance at 0x806f82ef0>
2018-01-15 19:17:29,148 [DEBUG] conn_0x806f87d90: Connection was lost (Connection was closed cleanly.).