[PATCH]Introduce generalized hooks for getting and setting inode secctx.

["David P. Quigley" <dpquigl-+05T5uksL2qpZYMLLGbcSA@public.gmane.org>]

This patch set does two things. First it factors the section of vfs_setxattr
that does the real work into a helper function. This allows LSMs the ability 
to set the xattrs they need without hitting the permission check inside
vfs_setxattr each time. Second it introduces three new hooks
inode_{get,set}secctx, and inode_notifysecctx.

The first hook retreives all security information the LSM feels is relavent in
the form of a security context. The second hook given this context can sets
both the in-core and on-disk store for the particular inode. The third hook is
used to notify the in-core inode of a change to it's security state.

This is the fourth revision of this patch set which takes into account
concerns by Casey Schaufler, and Christop Hellwig.

fs/xattr.c               |   57 ++++++++++++++++++++++++++++++++++-----------
include/linux/security.h |   50 ++++++++++++++++++++++++++++++++++++++++
include/linux/xattr.h    |    1 +
security/dummy.c         |   17 +++++++++++++
security/security.c      |   18 ++++++++++++++
security/selinux/hooks.c |   28 ++++++++++++++++++++++
6 files changed, 157 insertions(+), 14 deletions(-)