Vanilla Tor Connectivity Issues In Iran -- Directory Authorities Blocked?
Social media users and @mttp report that vanilla Tor no longer works.
Confirmed that Tor v0.2.2.35 out of the box fails to progress beyond:
Bootstrapped 5%: Connecting to directory server.
Same behavior confirmed on v0.2.4.23 built from source.
Fetched random bridge from bridges.tpo and applied to torrc, quickly bootstrapped through bridge and successfully confirmed access through check.tpo.
With stem-listed DAs, wrote python script to check connectivity to DAs based on a simple TCP connect(). For OR port, if successful, the cert sha1 was retrieved.
Connect Test Results for directory authorities:
Tonga 188.8.131.52 (OR: 443 , 14:C7:A1:55:82:1C:D4:81:5C:55:8F:25:E5:7F:CF:F0:3E:BF:67:30 ), (Dir: 80 , successful ) turtles 184.108.40.206 (OR: 9090 , timeout ), (Dir: 9030 , timeout ) dizum 220.127.116.11 (OR: 443 , timeout ), (Dir: 80 , timeout ) gabelmoo 18.104.22.168 (OR: 443 , timeout ), (Dir: 80 , timeout ) urras 22.214.171.124 (OR: 80 , timeout ), (Dir: 443 , timeout ) tor26 126.96.36.199 (OR: 443 , timeout ), (Dir: 80 , timeout ) moria1 188.8.131.52 (OR: 9101 , 97:4B:DD:96:D3:21:1F:52:F9:8C:0A:BB:7C:27:3B:19:7F:02:5A:1D ), (Dir: 9131 , successful ) dannenberg 184.108.40.206 (OR: 443 , timeout ), (Dir: 80 , timeout ) Faravahar 220.127.116.11 (OR: 443 , timeout ), (Dir: 80 , timeout ) maatuska 18.104.22.168 (OR: 80 , timeout ), (Dir: 443 , timeout )
TCP traceroute to Faravahar dies at the Telecommunications Company of Iran for all TCP ports (ICMP is fine).
traceroute to 22.214.171.124 (126.96.36.199), 30 hops max, 60 byte packets 1 [hop-1, responsive] 2 [hop-2, unresponsive] 3 [hop-3, responsive] 4 [hop-4, responsive] 5 188.8.131.52 (184.108.40.206) 1.300 ms 1.127 ms 1.334 ms 6 * * * 7 * * * 8 * * * 9 * * * 10 * * * [...]
Taken against the successful ICMP traceroute, the next hop hits 10.10.53.209 then exits Iran through PCCW Global. Based on the TCI's history in past disruptions, that this would occur at the international gateway is unsurprising and indicates that all users on unprivileged networks are likely blocked unless using a bridge.
For posterity, 10.10.53.209 only has one open port, HTTP on 80, which returns the "level 15 access" authentication message indicative that it is a Cisco router.