On Tue, 1 Aug 2006, Nikolas Britton wrote:

On 8/1/06, Robert Huff <[EMAIL PROTECTED]> wrote:
User Freebsd writes:
>  Actually, using ifconfig wouldn't work ... it would give unique, but as
> soon as you add another IP (ie. alias), the ID would change ... you'd need
>  to do something like:
>
>  ifconfig | grep ether | sha256 | md5
>
>  since the 'ether' would never change ...

        At least some cards (+ FreeBSD drivers) allow you to set the
MAC address ....




You still don't get it! Maybe this simple perl program will illustrate
the problem:

my $number = "100000000000000000000";
my $randomkey = "";
while (0 == 0) {
$randomkey = `echo $number | md5`;
print "fetch http://www.hub.org/freebsd_stats.php?HOSTID=$randomkey";;
$number++
}

Also by using only the mac address output of ifconfig you have limited
the pool of unique keys to 16^12 (281,474,976,710,656)!!! All I need
to do to find your mac address is compute all possible mac address
combinations into MD5 and then just simply match it up with yours.
Anonymity only works if the input is large then the output!!! Because
it's computationally impossible to compute all values of a 500+ byte
string etc. etc. The MD5 string maps back to at least  (how do you
compute the collisions?) two SHA256 keys and the SHA256 maps back to
at least two ifconfig strings.

Thing is, we aren't so much looking for anonymity as we are uniqueness, but, wouldn't the CPU serial id not be both?


----
Marc G. Fournier           Hub.Org Networking Services (http://www.hub.org)
Email . [EMAIL PROTECTED]                              MSN . [EMAIL PROTECTED]
Yahoo . yscrappy               Skype: hub.org        ICQ . 7615664
_______________________________________________
freebsd-questions@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-questions
To unsubscribe, send any mail to "[EMAIL PROTECTED]"

Reply via email to