Re: Safe destinations

[Peter Hultqvist <phq@xxxxxxxxxx>]

Drake Wilson skrev:
> My initial impulse would be to allow end sites to declare that they
> are willing to receive connections via Tor.  Using DNS records, for
> instance, of a style like:
>
>   _toraccept.example.net TXT "toraccept1: 80,443,6667,9000,7777,9999"
>     (and/or)
>   _toraccept.23.2.0.192.in-addr.arpa TXT "toraccept1: 5234,5269,11000-11999"
>
> Obviously you could include other information about which nodes should
> try to exit there, or other such stuff.
>   
The forward DNS is problematic since they can be spoofed by pointing any
domain to a server that does not belong to one. Second, I believe that
ptr lookup is very limited but I'm not that knowledgeable in that area.

One way could be to given an IP do an reverse lookup, take that domain,
add _toraccept and do a forward dns lookup at suggested above.

Another solution could be to use robot.txt(at the raw ip http/80
request, without host), this would make it much easier for most sited to
allow tor. Here one would add a line with "Allow: tor-anonymous".

In any case I would suggest that there will be a new flag for nodes that
flag them to be "target allowed" exit nodes. This would make it possible
for a client to guess and use one of those nodes as exit node to any ip
address, the node would then on connection check if the target server
specifically allows tor and otherwise deny the connection.

This way there would be no list to maintain more than local cache at the
nodes, and perhaps at the clients, but that would be a local design
decision not specific to the TOR protocol.