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Re: [Question] Signature calculation ignoring parts of binary files




"Randall S. Becker" <rsbecker@xxxxxxxxxxxxx> writes:

>> author is important to our process. My objective is to keep the original file
>> 100% exact as supplied and then ignore any changes to the metadata that I
>> don't care about (like Creator) if the remainder of the file is the same.

That will *not* work.  If person A gave you a version of original,
which hashes to X after you strip the cruft you do not care about,
you would register that original with person A's fingerprint on
under the name of X.  What happens when person B gives you another
version, which is not byte-for-byte identical to the one you got
earlier from person A, but does hash to the same X after you strip
the cruft?  If you are going to store it in Git, and if by SHA-1 you
are calling what we perceive as "object name" in Git land, you must
store that one with person B's fingerprint on it also under the name
of X.  Now which version will you get from Git when you ask it to
give you the object that hashes to X?