Add SHA-512/256 hash op and FIXED32_LITTLE length op

[kostko]

See discussion in cosmos/ibc#554.

[ethanfrey]

Thanks for this PR and nice to point out https://github.com/confio/ics23/pull/39/files#diff-946b8d2ee64b4b178e19710fbd2c831353ccef71968db74f051f482ca747afb4R167-R171

We aim to keep all 3 language implementations in sync, so this needs to be implemented for rust and typescript (in other folders).

If you can implement them, that would be great. If not, I will put this on my TODO list.

[kostko]

Whoops, missed that, yeah I can add the other implementations.

[kostko]

@ethanfrey Added the rest, Javascript is the most annoying.

[ethanfrey]

Looks good. One minor comment.

If you do fix that, please run cargo fmt on the rust code as well. Then it is good to merge.

[ethanfrey]

I would do = (l % 256). That is quite clear what you want. I think this will happen automatically in JS, but it is harder to review and ensure correctness.

[kostko]

Yeah makes sense, I prefer bitwise ops (e.g., l & 0xFF), but the linter doesn't like them for some reason.

[kostko]

Changed.

[ethanfrey]

Looks good. Thanks for your contribution.

[ethanfrey]

I pushed 0.6.5 rust crate and npm package.

I tagged for go, but I got some errors trying to update local files. I will try again for that.

There was a solution in #35 but I just get errors.

[kostko]

I tagged for go, but I got some errors trying to update local files. I will try again for that.

There was a solution in #35 but I just get errors.

Seems to work for me with both v0.6.5 and v0.6.6 (since your module is in a subfolder you need to use e.g. go/v0.6.6 as tags -- which you are). Note that you need to import this as github.com/confio/ics23/go so not sure why you also have a top-level go.mod file.

I would just remove that one (e.g., https://github.com/confio/ics23/blob/master/go.mod and corresponding go.sum) as it is confusing and unused.

[ethanfrey]

Note that you need to import this as github.com/confio/ics23/go so not sure why you also have a top-level go.mod file.

I would just remove that one (e.g., https://github.com/confio/ics23/blob/master/go.mod and corresponding go.sum) as it is confusing and unused.

Yes, it is confusing, and Zaki helped with the Go tagging. I can gladly remove the top level go.mod. For some reason I thought it was needed.

[ethanfrey]

BTW, if you need this in a build of the cosmos sdk, you need to manually update the dependency. And if you want it on the hub, maybe make a PR to bump the ics23 version, so it will be included in the next release