Request for review: Sandboxing dhclient using Capsicum.

[Brooks Davis]

On Sun, Jun 09, 2013 at 12:33:46AM +0200, Pawel Jakub Dawidek wrote:
> I'd appreciate any review, especially security audit of the proposed
> changes. The new and most critical function is probably send_packet_priv().

I've looked over the diff and not found any significant issues, but have
a few comments in order of most to least important.

In change 229477 using a cached hostname may change behavior if the host
is renamed as a result of dhclient operation.  The new behavior might be
more correct, at least it would be if we reliably restored the host name
on termination.  I think the change is fine, but we should be keep an
eye out for problem reports.

In change 229476 I noticed there is a constant 0x1fff that you've moved
around.  It was already there, but it seems like an unnecessary magic
number.

In the send_packet_* function declarations in dhcpd.h, you have included
variable names which is inconsistent with the surrounding definitions.

I saw a few style/whitespace fixed mixed in that should be batched,
probably before the substantive commits.

-- Brooks