Re: BSD jail

[Joshua Hudson <joshudson@gmail.com>]

On 8/13/05, Serge E. Hallyn <serue@us.ibm.com> wrote:
> The latest version (which is still quite old) is at
> http://www.sf.net/projects/linuxjail and does have ipv6 support.  The last
> time I submitted it, Christoph had objected to the way the networking was
> done in general.  I've tried twice to float a generalized "per-process
> network namespaces" patch, but haven't really found a good approach.
> 
> I suspect that the best approach would be to take the linux-vserver
> ngnet implementation and convert it to a standalone network namespace
> plus virtual network device implementation.  Do you care to give this
> a try?
> 
> thanks,
> -serge

Why would you want a virtual network device implementation? The whole
point of jail()
is a replacement for chroot() for housing untrusted root processes in
a lightweight
manner as reasonable.  I think in one way at least, I have restricted the manner
of jail behavior better than the current linuxjail, by turning off
capabilities rather than
blocking mknod(), mount(), etc.

I do like the idea of patching in through LSM, however not everything
can be done there.
In particular, I could escape from the jail as implemented there by a
classic chroot()
trick.