[tbb-dev] Tor unable to parse Bridge setting if using domain

[David Fifield]

On Tue, Aug 27, 2019 at 08:29:08PM -0300, Hikari wrote:
> Hello everybody! Sorry if I'm asking on the wrong list.

This is more of a Tor issue than a Tor Browser issue. But looking at
https://lists.torproject.org/cgi-bin/mailman/listinfo, I don't
immediately see an appropriate list. I know questions like this would be
welcome on the #tor IRC channel.

> I had setup a Tor bridge on my home server. When I test it using 4G it works.
> It happens that my ISP's dynamic IPs are blocked too. I managed to find a
> domain I can use and isn't blocked, so when I go to my server's web server
> using its IP I get blocked, but when I go using my domain I'm able to browse
> it.
> 
> Now I'm strugging to get Tor client at office to connect to my Tor bridge at
> home. If I use Bridge 51.113.0.17:80 (a obfuscated IP, not the current one) it
> fails as happens with most bridges on BridgeDB.
> 
> But when I use Bridge hikari.mydomain.com:80 (which works if accessed from a
> browser on port 8080) I get Error parsing Bridge address
> 'hikari.mydomain.com:80'. Failed to parse/validate config: Bridge line did not
> parse.
> 
> Any idea why it's not parsing domains on bridge setting?

About five years ago, tor would accept hostnames in bridge lines, but
stopped doing that here: https://bugs.torproject.org/10801.

I suspect that your problem is nothing really to do with hostname versus
IP address. After all, after resolving the name, tor is still just going
to connect to the IP address. More likely it is related to the port
and/or protocol. You say that tor on port 80 is blocked but HTTP on port
8080 works; it could be that the firewall is dynamically detecting the
Tor protocol and blocking it, while allowing HTTP. Try using an unlisted
obfs4 bridge from https://bridges.torproject.org/options and see if it
works.