gss_krb5: add ability to have a keyed checksum (hmac)

Encryption types besides DES may use a keyed checksum (hmac).
Modify the make_checksum() function to allow for a key
and take care of enctype-specific processing such as truncating
the resulting hash.

Signed-off-by: Kevin Coffman <[email protected]>
Signed-off-by: Steve Dickson <[email protected]>
Signed-off-by: Trond Myklebust <[email protected]>
6 files changed