fuzz: Differential fuzzing for ChaCha20Forward4064-Poly1305@bitcoin cipher suite

[stratospher]

This PR does an alternate implementation of the ChaCha20Forward4064-Poly1305@bitcoin cipher suite according to the new specification proposed in BIP 324. It performs differential fuzzing in order to ensure that the outputs obtained from #20962 and the alternate implementation are consistent.

The alternate implementation was successfully tested with the ChaCha20Poly1305@Bitcoin AEAD's test vectors in this branch. The first two commits in this PR are from #20962.

[DrahtBot]

The following sections might be updated with supplementary metadata relevant to reviewers and maintainers.

Conflicts

Reviewers, this pull request conflicts with the following ones:

• #24203 (doc: Fix typos pointed out by lint-spelling by brunoerg)
• #23233 (BIP324: Add encrypted p2p transport {de}serializer by dhruv)
• #20962 (Alter the ChaCha20Poly1305@Bitcoin AEAD to the new specification by jonasschnelli)

If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

[DrahtBot]

🐙 This pull request conflicts with the target branch and needs rebase.

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[DrahtBot]

There hasn't been much activity lately and the patch still needs rebase. What is the status here?

• Is it still relevant? ➡️ Please solve the conflicts to make it ready for review and to ensure the CI passes.
• Is it no longer relevant? ➡️ Please close.
• Did the author lose interest or time to work on this? ➡️ Please close it and mark it 'Up for grabs' with the label, so that it can be picked up in the future.

[achow101]

Are you still working on this?

[stratospher]

Closing this PR since this has been replaced with a better AEAD with formal security analysis in BIP 324.

And if anyone's interested in differential fuzzing(feel free to reach out!), I am working on fuzz testing python and cpp implementations of cryptography used in BIP 324 outside this repository. This would be a stronger test compared to the one in the PR since different programming languages are involved. See #23915.