On 10/13/2018 12:07 AM, Nathaniel Suchy wrote: > Currently tor traffic uses an TLS handshake hostname like the following: > > $ sudo tcpdump -An "tcp" | grep "www" > listening on pktap, link-type PKTAP (Apple DLT_PKTAP), capture size 262144 > bytes > .............". ...www.odezz26nvv7jeqz1xghzs.com......... > .............#.!...www.bxbko3qi7vacgwyk4ggulh.com......... > .6....m.....>...:.........|../* > Z....W....X=..6...C../....................................0...0..0.......'....F./0.. > *.H........0%1#0!..U....www.b6zazzahl3h3faf4x2.com0...160402000000Z..170317000000Z0'1%0#..U....www.tm3ddrghe22wgqna5u8g.net0..0.. > > A network observer could run a DNS lookup on the hostnames and see if > they are real or not. So my idea would be to register a set of random > hostnames which are legitimate and point the IPs somewhere to avoid > looking for an NX Domain response and dropping the stream. You could > even give each relay a unique subdomain and rotate these every few > weeks. This may be expensive to implement but could make blocking Tor > traffic with this method harder. Thoughts? >
Why wouldn't it be just as easy for censors to identify the small set of registered domains that Tor relays use and block TLS connections that involve them? I don't see how changing the domain a relay uses from aaaaaa.foo.com to bbbbbb.foo.com helps. The censor would just notice 'foo.com' and block it. In fact, I think this would make censorship easier. Matt _______________________________________________ tor-dev mailing list tor-dev@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev
