theta-idl VS constant-time

I've found it comes up pretty often. Sometimes because the logic I'm writing demands it—traversing over some kind of nested recursive structure, for example—but more often because it makes the code easier to read. A real-world example: I have a little interface description language which can generate code in a few different target languages. I want to factor out some of the more complex logic (eg dealing with record types) into self-contained, testable functions, which means that my top-level toDefinition function needs to call toRecord, which needs to call toDefinition for each of the record's fields[1].

(Sorry if it's hard to follow the code without context, but that's the problem with examples—either they're too trivial to be interesting, or they're complex enough to be a bit confusing!)

Additionally—and maybe even more importantly—tail call elimination also makes code written in continuation-passing style (CPS) more efficient. While CPS isn't something we usually want to write by hand, a lot of common abstractions (async libraries, promises, monads) map to CPS under the hood.

[1]: https://github.com/target/theta-idl/blob/stage/theta/src/The...

I noticed in July of 2022 that Go did exactly the vulnerable example and reported it to the security team.

https://github.com/golang/go/issues/53849

It was fixed as of Go 1.21 https://go.dev/doc/go1.21

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The article cites JavaScript, which is not constant time. There's no sure way to do constant time operations in JavaScript and thus no secure way to do crypto directly in Javascript. Browsers like Firefox depend on low level calls which should be implemented in languages that are constant time capable.

JavaScript needs something like constant time WASM in order to do crypto securely, but seeing the only constant time WASM project on GitHub has only 16 stars and the last commit was 2 years ago, it doesn't appear to have much interest. https://github.com/WebAssembly/constant-time

However, for JavaScript, I recommend Paul's library Noble which is "hardened to be algorithmically constant time". It is by far the best library available for JavaScript. https://github.com/paulmillr/noble-secp256k1

Also see the constant time spec: https://github.com/WebAssembly/constant-time

I'm waiting for constant time WASM. https://github.com/WebAssembly/constant-time/blob/main/propo...

Also: We're excited for constant time Wasm.