Re: musl 1.0.x branch

[Laurent Bercot <ska-dietlibc@skarnet.org>]

On 10/06/2014 17:03, Rich Felker wrote:

> FYI you can emulate the usefulness of suid, without the danger, by
> having a daemon on a unix socket that you connect to which provides
> the functionality. This is a vastly superior design because there is
> exactly one input channel to the code running with elevated privileges
> (the socket) as opposed to unboundedly many (environment, open fds,
> resource limits, working directory, priority, signal mask and
> dispositions, cpu affinity, ... and whatever else the kernel folks add
> in the future).

  And now there are even programs designed to help you do exactly that:
  http://skarnet.org/software/s6-networking/s6-sudo.html
  (Shameless plug of the day: achieved)

  However, despite being a good solution for noninteractive programs, the
unix socket mechanism isn't perfect. There are a lot of things it cannot
transmit without significant trouble - in particular terminals and
everything job-control-related, and signals, etc. I've done quite a bit
of thinking while writing s6-sudo, and my conclusion was that it's a
daunting task to get everything working properly with programs that
need a terminal; it would require ugly wrappers à la ptyget, and more.
I'm not convinced it's even worth trying, as opposed to tackling the
existing terminal-using privilege-granting programs and kicking the
suid out of them.

-- 
  Laurent