bao

I mostly agree with you, but there are a couple other bullet points I like to throw in the mix: - Length extension attacks. I think all of the SHA-3 candidates did the right thing here, and we would never accept a new cryptographic hash function that didn't do the right thing here, but SHA-2 gets a pass for legacy reasons. That's understandable, but we need to replace it eventually. - Kind of niche, but BLAKE3 supports incremental verification, i.e. checking the hash of a file while you stream it rather learning whether it was valid at the end of the stream. https://github.com/oconnor663/bao. That's useful if you know the hash of a file but you don't necessarily trust the service that's storing it.

We go over some of our reasoning around that in section 7.5 of https://github.com/BLAKE3-team/BLAKE3-specs/blob/master/blak.... An early BLAKE3 prototype actually didn't include the chunk counter (https://github.com/oconnor663/bao/blob/master/docs/spec_0.9....), so I'm definitely sympathetic to the use cases that wish it wasn't there. However, after publication we found out that something like a chunk counter is necessary for the security of the Bao streaming verification tool: https://github.com/oconnor663/bao/issues/41. It could be that there's a design that's the best of both worlds, but I'm not sure.