bitcoin/contrib/verify-commits
Wladimir J. van der Laan b2e5fe8b55
Merge #12708: Make verify-commits.sh test that merges are clean
577f111 Make verify-commits.sh test that merges are clean (Pieter Wuille)

Pull request description:

  Unsure if we want this.

  This modifies verify-commits.sh to redo all merges along the leftmost commit branch (which includes all PR merges), and verify whether they match the merge commit's trees.

  The benefit is that it will detect a case where one of the maintainers merges a PR, but makes an unrelated change inside the merge commit. This on itself is not very strong, as unrelated changes can also be included in the merged branch itself - but perhaps the merge commit is not something that people are otherwise likely to look at.

  Fixes #8089

Tree-SHA512: 2c020f5ac3f771ac775aa726832916bb8e03a311b2745d7a9825047239bd0660d838f086f3456f2bb05cea14c1529f74436b8cdd74cc94b70e40b4617309f62c
2018-04-07 18:48:27 +02:00
..
allow-revsig-commits Add Marco-expired-key-signed-commits to allow-revsig-commits 2018-03-28 14:55:50 -04:00
gpg.sh [verify-commits] Fix gpg.sh's echoing for commits with '\n' 2017-12-05 15:21:23 -05:00
pre-push-hook.sh [copyright] add MIT license headers to .sh scripts where missing 2016-09-11 13:36:22 -06:00
README.md [verify-commits] Add some additional useful documentation. 2018-03-29 10:31:56 -04:00
trusted-git-root Revert "test: Update trust git root". 2018-03-28 14:55:50 -04:00
trusted-keys Allow any subkey in verify-commits 2017-03-04 09:41:16 -05:00
trusted-sha512-root-commit Update trusted-sha512-root-commit for new bad tree hash 2017-03-09 09:53:19 -05:00
verify-commits.sh Make verify-commits.sh test that merges are clean 2018-03-16 10:24:59 -07:00

Tooling for verification of PGP signed commits

This is an incomplete work in progress, but currently includes a pre-push hook script (pre-push-hook.sh) for maintainers to ensure that their own commits are PGP signed (nearly always merge commits), as well as a script to verify commits against a trusted keys list.

Using verify-commits.sh safely

Remember that you can't use an untrusted script to verify itself. This means that checking out code, then running verify-commits.sh against HEAD is not safe, because the version of verify-commits.sh that you just ran could be backdoored. Instead, you need to use a trusted version of verify-commits prior to checkout to make sure you're checking out only code signed by trusted keys:

git fetch origin && \
  ./contrib/verify-commits/verify-commits.sh origin/master && \
  git checkout origin/master

Note that the above isn't a good UI/UX yet, and needs significant improvements to make it more convenient and reduce the chance of errors; pull-reqs improving this process would be much appreciated.

Configuration files

  • trusted-git-root: This file should contain a single git commit hash which is the first unsigned git commit (hence it is the "root of trust").
  • trusted-sha512-root-commit: This file should contain a single git commit hash which is the first commit without a SHA512 root commitment.
  • trusted-keys: This file should contain a \n-delimited list of all PGP fingerprints of authorized commit signers (primary, not subkeys).
  • allow-revsig-commits: This file should contain a \n-delimited list of git commit hashes. See next section for more info.

Key expiry/revocation

When a key (or subkey) which has signed old commits expires or is revoked, verify-commits will start failing to verify all commits which were signed by said key. In order to avoid bumping the root-of-trust trusted-git-root file, individual commits which were signed by such a key can be added to the allow-revsig-commits file. That way, the PGP signatures are still verified but no new commits can be signed by any expired/revoked key. To easily build a list of commits which need to be added, verify-commits.sh can be edited to test each commit with BITCOIN_VERIFY_COMMITS_ALLOW_REVSIG set to both 1 and 0, and those which need it set to 1 printed.