replace uname -a informational string

[Fabian Keil]

"O. Hartmann" <ohartman at zedat.fu-berlin.de> wrote:

> Am Fri, 23 Oct 2015 23:56:12 -0400
> "Michael B. Eichorn" <ike at michaeleichorn.com> schrieb:
> 
> > On Sat, 2015-10-24 at 08:09 +0800, Erich Dollansky wrote:
[...]
> > > On Fri, 23 Oct 2015 22:54:24 +0200
> > > "O. Hartmann" <ohartman at zedat.fu-berlin.de> wrote:
> > >   
> > > > Am Fri, 23 Oct 2015 13:45:25 -0400
> > > > "Michael B. Eichorn" <ike at michaeleichorn.com> schrieb:
[...]
> > > > > On Fri, 2015-10-23 at 09:08 +0200, O. Hartmann wrote:  
> > > > > > For security purposes, I need to replace the informations given
> > > > > > by
> > > > > > "uname -a"
> > > > > > to hode the kernel build system, name et cetera.    
> > > > > 
> > > > > I presume you intendend 'hide' here?
> > > > > 
> > > > > If you want to scrub a binaries of _all_ information about the
> > > > > building system this is a problem Debian is actively working on
> > > > > called 'reproducible builds' but is not possible today.
> > > > > 
> > > > > https://reproducible.debian.net
> > > > > 
> > > > > If you want to hide the hostname, why not just build with a
> > > > > different hostname set?  
> > > > 
> > > > Because it is not only the hostname, uname reveals the target host,
> > > > date and OS version.
> > > > 
> > > > In our case, the image ist built on a dedicated host for a security
> > > > appliabce based on NanoBSD and I'd like to hide the OS type, the OS
> > > > name, the build box' name and the build date. 
> > > >   
> > > why not replace uname at the source level then?
[...]
> > That wouldn't hide the information in any substantial way. Uname is
> > basically an abstraction of a subset of sysctls. As such, the information
> > is integral to the kernel itself. Uname is just one of many tools that
> > can be used to display this information.
> > 
> > Fundamentally the kernel itself needs to be changed not uname.
> 
> I'm well aware of that fact. At many places, the build-process sets variables from the
> outside world while building binaries and kernel and since I build everything from
> scratch, I intend to manipulate those variables - if possible.

It's possible and already done on FreeBSD consumers like
ElectroBSD as one of the steps to get reproducible builds.

The variables are set by sys/conf/newvers.sh and most of them can
already be overwritten through the environment.

Fabian
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 181 bytes
Desc: OpenPGP digital signature
URL: <http://lists.freebsd.org/pipermail/freebsd-questions/attachments/20151024/44080894/attachment.bin>