On Tue, Aug 27, 2013 at 11:12:01PM +0200, Tor Exit wrote:
Why is it so bad if a Tor exit operator tries to match the use of their node with their own moral beliefs?
I really would like to support this if I could.
Specifically, I'd love a way for exit relay operators to only allow people to do things *via their exit relay* that they're comfortable with.
The trouble is, I only want to do it if we can have a way for Tor clients to automatically learn what each exit will allow, so they can pick an exit that will allow their connection.
We have that working with exit policies right now: each relay advertises what IP blocks and ports it will allow, and then clients learn all the exit policies and automatically choose an exit that will support their stream. See Andy's post for details: https://lists.torproject.org/pipermail/tor-relays/2013-August/002560.html
The trouble with more fine-grained approaches, where you look at the content of the communication rather than the address of it, is that the Tor client doesn't know the entirety of the communication when it's selecting the path to use. This seems like an inherent contradiction, especially since the client will need to know, ahead of time, everything the *destination* (e.g. website) will send too.
(Ok, that's just the technical trouble. There are also legal troubles with filtering some things you consider bad while not filtering everything that anybody could consider bad. See the EFF Tor legal faq.)
--Roger