On 1/16/12 8:46 AM, Karsten Loesing wrote:
On 1/11/12 10:34 AM, Linus Nordberg wrote:
Alex Le Heux alexlh@funk.org wrote Wed, 11 Jan 2012 09:57:00 +0100:
| > RFC 3849 defines the prefix 2001:DB8::/32 as being reserved for | > documentation. That should be fine for this. | | The documentation prefix is for just that, use in documentation :) | | ULA (RFC4193) is actually closer to the 10/8 (RFC1918) addresses that you use for IPv4.
Oh, right. *blush*
So, just to get that right: how would we apply RFC4193 here?
We start with FC00::/7 as the prefix for Local IPv6 unicast addresses.
We set the 8th bit, the L bit, to 1, because we're generating the
subsequent Global ID locally.
- We generate a random 40-bit Global ID for "Tor sanitized bridge IPv6
addresses." We don't change it, ever.
We set the 16-bit Subnet ID to all zeros.
We use the least significant 24 bits of the 64-bit Interface ID for
the actual sanitized bridge address that was formerly encoded in 10.x.x.x.
As an example, a sanitized IPv6 bridge address would be:
[fc01:0123:4567:89ab::fedc:ba98:7654]
Err... What I meant was something like this:
[fd9f:2e19:3bcf::f8:2444]
Does that make sense?
The approach discussed above is now implemented:
https://gitweb.torproject.org/metrics-db.git/commitdiff/70a3d998
Unless somebody shouts at me within the next 48 hours and tells me the approach is stupid, I'm going to deploy it.
Best, Karsten