This allows the sign command to work on BIOS images with
invalid VBLOCK areas. When re-signing an existing image, the
length of the firmware body is part of the firmware preamble
in the VBLOCK areas. If those are invalid, the BIOS can
still be signed, but it will have to sign the entire FW_MAIN
area. That's a little slower to verify, so we'd prefer not
to do that, but it works.
BUG=chromium:224734
BRANCH=ToT
TEST=make runtests
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Change-Id: If58b5c86c5df12f004eabff72c22bfb1e84de7fd
Reviewed-on: https://chromium-review.googlesource.com/216229
Reviewed-by: Randall Spangler <rspangler@chromium.org>