Re: dhclient: avoiding hostname disclosure via DHCP request

[Dan Williams <dcbw redhat com>]

On Mon, 2014-01-06 at 17:35 +0000, Robert Horovitz wrote:
> Hi Dan,
>
> thanks for your reply.
>
> > Ah, sorry.  That block is for the connection files
> > in /etc/NetworkManager/system-connections, if that's where the
> > connection is stored.
> >
> > If the connection is instead stored in an ifcfg file on Fedora or RHEL,
> > then you'll want to use "DHCP_SEND_HOSTNAME=no" in the ifcfg file for
> > the connection in /etc/sysconfig/network-scripts/
>
> /etc/NetworkManager/system-connections is an empty folder so I went
> ahead and added "DHCP_SEND_HOSTNAME=no" to
> /etc/sysconfig/network-scripts/ifcfg-<SSID>
>
> (a WIFI connection)
>
> unfortunately I still see my hostname in the DHCP Request packets
> (wireshark).
> I even tried a reboot to see if this change requires a reboot, but no luck.
>
> Is this a bug in a rarely used config option or am I still doing
> something wrong?

This turns out to be a bug in the 'ifcfg-rh' config file parsing plugin.
I've fixed it in git upstream, but a temporary workaround would be:

DHCP_HOSTNAME=wont-be-used
DHCP_SEND_HOSTNAME=no

DHCP_SEND_HOSTNAME was only parsed if DHCP_HOSTNAME was also given.

Dan