Please take a review at http://cr.openjdk.java.net/~weijun/8229775/webrev.00/
The updated code checks both SHA-256-Digest-Manifest and SHA-256-Digest-Manifest-Main-Attributes. The latter should always appear in a SF file generated by our own jarsigner but theoretically it could be missing if MANIFEST.MF has no header. Anyway, checking both is more reliable. Thanks, Max
