[Pkg-utopia-maintainers] Bug#771077: macchanger package installed?

[Martin Steigerwald]

Am Sonntag, 30. November 2014, 10:25:02 schrieb Alexander Dreweke:
> Hi Martin,

Hi Alexander,
 
> could it be, that you have the macchanger package installed? This
> package brings along 2 ifup/down scripts:

Indeed I have:

merkaba:~> apt-show-versions 2>/dev/null | grep macchanger
macchanger:amd64/sid 1.7.0-3.1 uptodate
macchanger:i386 not installed

I don´t know why tough as nothing in my system reverse depends on it. Maybe I 
thought at some day it would be nice to have in case I want to surf privately 
somewhere.

> /etc/network/if-post-down.d/macchanger
> /etc/network/if-pre-up.d/macchanger
> 
> These hooks change the mac address to random values. It seems, that by
> default the post-down hook is enabled, but you can be disabled via:
> 
> /etc/default/macchanger

And post-down hook is enabled:

merkaba:~> head -5 /etc/default/macchanger 
# before bringing up any network interface, run macchanger. Careful, this is
# not guaranteed to prevent leaking your real MAC address before the new one
# gets assigned!
#
ENABLE_ON_POST_DOWN=yes

I set it to "no" but the MAC address still is changed on disconnecting:

- I set the MAC to the correct value
- I go online
- It stays that way
- I go offline
- I always get "b4:9e:e6:eb:77:d0" as MAC address


That doesn´t make sense as the macchanger script really respects this setting:

merkaba:~> tail -3 /var/log/macchanger.log
disabled in /etc/default/macchanger
disabled in /etc/default/macchanger
disabled in /etc/default/macchanger


I even purged the package, still to no avail.

And I have no reference to that MAC address in

merkaba:/etc> grep -ir "b4:9e:e6:eb:77:d0" .
merkaba:/etc>


Okay, this time Network Manager does it:

merkaba:~> grep "reset MAC" /var/log/daemon.log | tail -3
Nov 30 11:21:17 merkaba NetworkManager[28834]: <info> (eth0): reset MAC 
address to B4:9E:E6:EB:77:D0
Nov 30 11:25:09 merkaba NetworkManager[28834]: <info> (eth0): reset MAC 
address to B4:9E:E6:EB:77:D0
Nov 30 11:25:59 merkaba NetworkManager[28834]: <info> (eth0): reset MAC 
address to B4:9E:E6:EB:77:D0

This seems unintuitive for me. Maybe it carries some state. Thus restarting 
Network Manager.

Okay, now this does work. Even with macchanger installed and post down hook 
disabled MAC address stays stable now.


Anyway I think the macchanger default is questionable, at least without 
telling people about it on package install. I am leaving this report open for 
consideration of this.

Thank you very much for that pointer, Alex.

Ciao,
-- 
Martin 'Helios' Steigerwald - http://www.Lichtvoll.de
GPG: 03B0 0D6C 0040 0710 4AFA  B82F 991B EAAC A599 84C7