Re: [PATCH] net: change capability used by socket options IP{,V6}_TRANSPARENT

[Balazs Scheidler <bazsi@balabit.hu>]

On Fri, 2011-09-02 at 12:10 -0700, Maciej Żenczykowski wrote:
> From: Maciej Żenczykowski <maze@google.com>
> 
> Up till now the IP{,V6}_TRANSPARENT socket options (which actually set
> the same bit in the socket struct) have required CAP_NET_ADMIN
> privileges to set or clear the option.
> 
> - we make clearing the bit not require any privileges.
> - we deprecate using CAP_NET_ADMIN for this purpose.
> - we introduce a new capability CAP_NET_TRANSPARENT,
>   which is tailored to allow setting just this bit.
> - we allow either one of CAP_NET_TRANSPARENT or CAP_NET_RAW
>   to set this bit, because raw sockets already effectively
>   allow you to emulate socket transparency, and make the
>   transition easier for apps not desiring to use a brand
>   new capability (because of header file or glibc support)
> - we print a warning (but allow it) if you try to set
>   the socket option with CAP_NET_ADMIN privs, but without
>   either one of CAP_NET_TRANSPARENT or CAP_NET_RAW.
> 
> The reason for introducing a new capability is that while
> transparent sockets are potentially dangerous (and can let you
> spoof your source IP on traffic), they don't normally give you
> the full 'freedom' of eavesdropping and/or spoofing that raw sockets
> give you.
> 
> Signed-off-by: Maciej Żenczykowski <maze@google.com>
> CC: Balazs Scheidler <bazsi@balabit.hu>

This is ok for me, as long as the security maintainers allow the
introduction of this new cap.

Thanks for doing this and sorry for the late reply.

Acked-by: Balazs Scheidler <bazsi@balabit.hu>

-- 
Bazsi