[tor-bugs] #10412 [Pluggable transport]: IPv6 Support By Pluggable Transport

[Tor Bug Tracker & Wiki]

#10412: IPv6 Support By Pluggable Transport
-------------------------------------+-----------------
     Reporter:  sysrqb               |      Owner:  asn
         Type:  enhancement          |     Status:  new
     Priority:  normal               |  Milestone:
    Component:  Pluggable transport  |    Version:
   Resolution:                       |   Keywords:
Actual Points:                       |  Parent ID:
       Points:                       |
-------------------------------------+-----------------

Comment (by asn):

 Replying to [ticket:10412 sysrqb]:
 > Tor clients can't send a proxy request for an ipv6 address connection to
 a pluggable transport if the PT says it supports socks4. This is not so
 good because IPv6 addresses are becoming more prevalent. The three
 options, as I see them, are:
 >
 >  - Change pt-spec to state that PTs can support either socks4a or socks5
 (and change Tor and implementation to adhere to this)

 This is currently the case, right? But socks4a doesn't support IPv6
 either.

 >  - If a PT supports IPv6 addresses then it must use SOCKS5.

 Yep. #9221 is the relevant ticket here.
 The problem with SOCKS5 is that it only supports 255 bytes of
 username/password, which is the field we are using as a covert channel to
 pass PT parameters. I have considered making a custom SOCKS5 handshake
 (using the reserved codes) to allow bigger username/passwords, but I'm not
 sure if it's worth the effort just yet.

 >  - Allow a PT to claim it supports both socks4 and socks5 in the CMETHOD
 line and Tor will need to decide which SOCKS version to use depending on
 the IP version.
 >

 Interesting idea, but why not always go for SOCKS5 if it's available?

 > The first one seems like a good idea. The second requires no spec change
 but will cause some pain with existing PTs. The last seems useful but
 requires a lot of modifications and so it's unnecessary.
 >
 > (Thanks to dcf1 and arma for their help)

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/10412#comment:1>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
The Tor Project: anonymity online