From: NeilBrown <neilb@cse.unsw.edu.au>

From: "J. Bruce Fields" <bfields@fieldses.org>

rpcsec_gss supports three security levels:

1.  authentication only: sign the header of each rpc request and response.

2. integrity: sign the header and body of each rpc request and response.

3.  privacy: sign the header and encrypt the body of each rpc request and
   response.

The first 2 are already supported on the client; this adds integrity support
on the server.