[Novalug] IPV6 Questions

Mackenzie Morgan macoafi@gmail.com
Tue Jul 22 16:34:22 EDT 2008


On Tue, Jul 22, 2008 at 4:30 PM, Gregory Maxwell <gmaxwell@gmail.com> wrote:
> On Tue, Jul 22, 2008 at 4:23 PM, Mackenzie Morgan <macoafi@gmail.com> wrote:
>> Hm...Greg, are you talking about something like Teredo or Miredo?
>
> I'm talking about 6to4 which is similar in application to Teredo.
>
>> Because your IPv4 address and IPv6 address should most definitely
>> *not* be mappable.  Yes, Windows Mobile does use some stupidly simple
>> algorithm to map them together, but that gets rid of the little bit of
>> security-through-obscurity gained by having a huge address-space in
>> which to take a stab-in-the-dark.  It's no longer a stab-in-the-dark,
>> but very easy to figure out which IPv6 addresses will be possible
>> based on which ones can map to IPv4 using a given algorithm.
>
> Nah, it only makes 48 bits of it obvious, but the rest is still obscure.
>
> For example, my IPv6 address on my laptop at home right now is:
>
> 2002:47bf:878c:feed:<snip>
>
> 2002: is the prefix used for 6to4.  47bf:878c  is my 32 bit VZN FIOS
> IPv4 address (encoded in hex).   :feed: is a random address I assigned
> to the wireless network here (the wired network is beef) and the rest
> is the ipv6 autoconf address derrived from my laptop's wireless card's
> MAC address.

Ah ok.  The algorithm for Windows Mobile is stupid.  I don't know if
it's Windows Mobile with Sprint specifically, or all of them, but they
all have the same first 64bits then the 32bit IPv4 address is simply
repeated in hex twice for the last 64bits.  D'oh!

-- 
Mackenzie Morgan
Linux User #432169
ACM Member #3445683
http://ubuntulinuxtipstricks.blogspot.com <-my blog of Ubuntu stuff
apt-get moo



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