I searched for the Snowflake bridge in Atlas, and couldn't find it. Its fingerprint is 2B280B23E1107BB62ABFC40DDCC8824814F80A72. Its torrc is stock "Last updated 9 October 2013 for Tor 0.2.5.2-alpha" except for these settings: ContactInfo David Fifield dcf@torproject.org SOCKSPort 0 ORPort 9001 BridgeRelay 1 ExtORPort auto ServerTransportPlugin snowflake exec /usr/local/bin/snowflake-server --acme-hostnames snowflake.bamsoftware.com --acme-email dcf@torproject.org --log /var/log/tor/snowflake-server.log ServerTransportListenAddr snowflake 0.0.0.0:443
Its ORPort 9001 is blocked by the local firewall, because it is meant to be only a Snowflake bridge, and not a vanilla bridge. (Most of the default Tor Browser obfs4 bridges are configured the same way, with their ORPort blocked.) There are these messages in the log (which I exxpected): [warn] Your server (37.218.242.151:9001) has not managed to confirm that its ORPort is reachable. Please check your firewalls, ports, address, /etc/hosts file, etc.
Why is the bridge not appearing in Atlas? I initially suspected https://bugs.torproject.org/18050, whose changelog entry is: - Check that both the ORPort and DirPort (if present) are reachable before publishing a relay descriptor. Otherwise, relays publish a descriptor with DirPort 0 when the DirPort reachability test takes longer than the ORPort reachability test. Closes bug #18050. Reported by "starlight", patch by "teor". Bugfix on 0.1.0.1-rc, commit a1f1fa6ab on 27 Feb 2005. But if it's the case that an unreachable ORPort causes descriptors not to be uploaded, then why do the default obfs4 bridges appear in Atlas? For example: https://atlas.torproject.org/#details/D9C805C955CB124D188C0D44F271E9BE57DE21... https://atlas.torproject.org/#details/D3D4A456FCB5F301F092F6A49ED671B84B432F... https://atlas.torproject.org/#details/11A3982C417AF37230F576006405BE5338F41C... Actually, now that I look at it, I notice some other default bridges are not present in Atlas, for example the two from https://bugs.torproject.org/21917, which went out in Tor Browser 6.5.2: C8CBDB2464FC9804A69531437BCF2BE31FDD2EE4 0BAC39417268B96B9F514E7F63FA6FBA1A788955
What's going on and how can we fix it? You can find a list of default bridge fingerprints here: https://gitweb.torproject.org/builders/tor-browser-bundle.git/tree/Bundle-Da...