Merge bitcoin/bitcoin#27058: contrib: Improve verify-commits.py to work with maintainers leaving

14fac808bd6c12bce121011bbf50501960c7326f verify-commits: Mention git v2.38.0 requirement (Andrew Chow)
bb86887527d817ee2a015863ddf3541dac42080f verify-commits: Skip checks for commits older than trusted roots (Andrew Chow)
5497c1483097a9b582ef78089a2ce1101b7d722e verify-commits: Use merge-tree in clean merge check (Andrew Chow)
76923bfa09397568fb8eb72142468a986fc6f790 verify-commits: Remove all allowed commit exceptions (Andrew Chow)
53b07b2b47aa3d4ca80fac74e432783a1e724df3 verify-commits: Move trusted-keys valid sig check into verify-commits itself (Andrew Chow)

Pull request description:

  Currently the `verify-commits.py` script does not work well with maintainers giving up their commit access. If a key is removed from `trusted-keys`, any commits it signed previously will fail to verify, however keys cannot be kept in the list as it would allow that person to continue to push new commits. Furthermore, the `trusted-keys` used depends on the working tree which `verify-commits.py` itself may be modifying. When the script is run, the `trusted-keys` may be the one that is intended to be used, but the script may change the tree to a different commit with a different `trusted-keys` and use that instead!

  To resolve these issues, I've updated `verify-commits.py` to load the `trusted-keys` file and check the keys itself rather than delegating that to `gpg.sh` (which previously read in `trusted-keys`). This avoids the issue with the tree changing.

  I've also updated the script so that it stops modifying the tree. It would do this for the clean merge check where it would checkout each individual commit and attempt to reapply the merges, and then checking out the commit given as a cli arg. `git merge-tree` lets us do basically that but without modifying the tree. It will give us the object id for the resulting tree which we can compare against the object id of the tree in the merge commit in question. This also appears to be quite a bit faster.

  Lastly I've removed all of the exception commits in `allow-revsig-commits`, `allow-incorrect-sha512-commits`, and `allow-unclean-merge-commits` since all of these predate the commits in `trusted-git-root` and `trusted-sha512-root`. I've also updated the script to skip verification of commits that predate `trusted-git-root`, and skip sha512 verification for those that predate `trusted-sha512-root`.

ACKs for top commit:
  Sjors:
    ACK 14fac808bd6c12bce121011bbf50501960c7326f
  glozow:
    Concept ACK 14fac808bd6c12bce121011bbf50501960c7326f

Tree-SHA512: f9b0c6e1f1aecb169cdd6c833b8871b15e31c2374dc589858df0523659b294220d327481cc36dd0f92e9040d868eee6a8a68502f3163e05fa751f9fc2fa8832a

0 files changed, 0 insertions, 0 deletions