Linus Torvalds wrote:

On Tue, 13 May 2003, David Howells wrote:

quoted

 (1) PAG (Process Authentication Group) support. A PAG is ID'd by a unique
     number, and is represented in memory as a structure that has a ring of
     associated authentication tokens.

     Each process can either be part of a PAG, or it can PAG-less - in
     which case it has no authentication tokens.

     Two new syscalls are added: setpag and getpag.

I think the code looks pretty horrible,

Any particular bits?

but I think we'll need something like this to keep track of keys. However,
I'm not sure we should make this a new structure - I think we should make
the current "tsk->user" thing _be_ the "PAG".

Maybe... There are arguments either way, but if the token ring is kept in
struct user, a task can't detach from it and pass a token-less set of keys
onto another process it wants to run.

Also, using a separate PAG structure means that you can lend your keys to an
SUID program and conversely it means a SUID program can't so easily gain
access to keys it didn't inherit from its caller.

I'm not sure that the ability to arbitrarily join a PAG should be permitted,
but it was requested.

David