RFC: Network privilege separation.

[Michael Stone <michael@laptop.org>]

Dear lkml and netdev,

I'm trying to implement a kernel facility for unprivileged processes to
irrevocably discard their and their future children's ability to perform
unrestricted network I/O. (Restricted network I/O, e.g. on sockets which were
connected before the privilege-reduction or on filesystem-based sockets is
okay.)

I want the kernel to provide a facility like this one because such a facility
will make it much easier for users, authors, and distributors of userland
software to protect themselves and one another from a broad class of malicious
software.

For the sake of discussion, I have written up and documented one possible
implementation of this concept based on the idea of a new rlimit named
RLIMIT_NETWORK in the following patch series. 

I eagerly await your questions, comments, suggestions, and improvements.

Thanks very much,

Michael

P.S. - I'm not subscribed to either lkml or netdev, so please CC me on
responses. Thanks!