Bug#427605: ITP: privbind -- Allow unprivileged apps to bind to a privileged port

[Shachar Shemesh <shachar@debian.org>]

martin f krafft wrote:
> How? Could you include a short note on how it does this "magic" in
> the description please?
>
>   
I'll do (arguably) better. I'll link to a not so short description at
http://privbind.svn.sourceforge.net/viewvc/privbind/trunk/README?view=markup

In a nutshell, privbind uses a 100% user space approach that does not
rely on SUID executables or on global configs (unlike authbind).
Instead, a root process runs privbind, which drops privileges and runs
the actual program. Privbind does leave a root process behind, and wraps
the program run with a LD_PRELOAD library that intercepts the "bind"
call, and forwards its file descriptor through an open UNIX domain
socket to the root process, which carries out the actual bind.

Shachar