I have a tarball from a point in time from a multi-year project. The tarball was supposedly from a particular release and the project tags the commit corresponding to each release. However the content of the tarball doesn’t match that from the git tag.

Usually I’m navigating git commits seeing what files looked like in the past. In this case I’ve got the file contents, but wondering which commit(s) match that content.

Can I take a sample file from the tarball and search the git history for a file with matching content?

The git log -S<string> option looks promising. Can I feed an entire (500 line) file to it as the search criteria?

Also git log --find-object=<object-id> offers hope. Can I hash (e.g. sha1sum) a standalone file and search for files within git that have the same content and hence the same hash?