[tor-talk] Does obfsproxy make any sense for relays

[Robert Ransom]

On 2012-02-29, MacLemon <tor at maclemon.at> wrote:

> I was wondering if building tor with obfsproxy would make any sense for a
> relay. The documentation suggests that obfsproxy is rather exclusive for
> bridges yet isn’t absolutely clear about that.
>
> The only scenario I can fabricate is someone blocking tor by DPI, being
> confident that they can block any tor traffic and subsequently doesn’t
> bother to explicitly block relay IPs anymore. Doesn’t seem too realistic to
> me.
>
> Would it hurt to implement obfsproxy into a relay?

We don't know.  We were worried that https://bugs.torproject.org/1776
would crash clients who use an obfsproxy with a relay behind it, but
I've had a Tor 0.2.3.12-alpha-dev client running for over a day
configured to use a relay as a bridge, and so far I haven't seen a
crash.

I'll be willing to declare that clients which use microdescriptors
aren't susceptible to #1776 after a week or two (to ensure that moria1
has changed its onion key, and this issued a new microdescriptor).
That won't help clients that are configured to also use a bridge
running 0.2.2.x, but hopefully no one who uses obfsproxy will try to
also use a regular bridge.

I should start another Tor client with microdescriptors disabled, too.
 Maybe that will help us find (and fix) #1776, if it's still around in
0.2.3.x.


Robert Ransom