On Mon, Nov 16, 2020 at 10:35 AM Mimi Zohar <zo...@linux.ibm.com> wrote:
>
> We need to differentiate between signed files, which by definition are
> immutable, and those that are mutable. Appending to a mutable file,
> for example, would result in the file hash not being updated.
> Subsequent reads would fail.
Why would that require any reading of the file at all AT WRITE TIME?
Don't do it. Really.
When opening the file write-only, you just invalidate the hash. It
doesn't matter anyway - you're only writing.
Later on, when reading, only at that point does the hash matter, and
then you can do the verification.
Although honestly, I don't even see the point. You know the hash won't
match, if you wrote to the file.
Linus
