ring VS ed25519-dalek

Again, this is just a temporary situation, and a matter of burning down a list of small tasks. Not that the OpenSSL license issue is a big deal for most anyway. Feel free to help; see this issue filed by Josh Triplett: https://github.com/briansmith/ring/issues/1318#issuecomment-...

Note also that rustls depends on ring, which has architecture-dependent code in it that is not as widely compatible as eg. OpenSSL/GnuTLS/Mbed-TLS. For example, MIPS is not supported by ring.

The AWS Rust library we were using as a dependency depended on a cryptography library called ring. This library leverages C and assembly code to implement its cryptographic primitives. Unfortunately, cross compiling when C is involved can add complexity to the build process. While it might've been possible to overcome these issues I decided that it wasn't worth digging into more.

That'd be great. Thanks Brian. Re: making ring portable to all platforms: IBM have been graciously maintaining a up to date patchset for Ring for years now and there's an outstanding PR here you may not have seen since they filed it in 2020... https://github.com/briansmith/ring/pull/1057

Beyond the simple matter of Rust being much newer than OpenSSL, one concern for some cryptographic primitives is the timing side-channel.

https://en.wikipedia.org/wiki/Timing_attack

In high level languages like Rust, the compiler does not prioritise trying to emit machine code which executes in constant time for all inputs. OpenSSL has implementations for some primitives which are known to be constant time, which can be important.

One option if you're working with Rust anyway would be use something like Ring:

https://github.com/briansmith/ring

Ring's primitives are just taken from BoringSSL which is Google's fork of OpenSSL, they're a mix of C and assembly language, it's possible (though fraught) to write some constant time algorithms in C if you know which compiler will be used, and of course it's possible (if you read the performance manuals carefully) to write constant time assembly in many cases.

In the C / assembly language code of course you do not have any safety benefits.

It can certainly make sense to do this very tricky primitive stuff in dangerous C or assembly, but then write all the higher level stuff in Rust, and that's the sort of thing Ring is intended for. BoringSSL for example includes code to do X.509 parsing and signature validation in C, but those things aren't sensitive, a timing attack on my X.509 parsing tells you nothing of value, and it's complicated to do correctly so Rust could make sense.

machine learning, neural networks, image processing, cryptography (though it is getting better), font shaping/rendering (though it is getting better), CPU/software rendering (though it is getting better)

Much of what you'll find highly visibly will be high-level libraries, but look at their dependencies. For example, from the ed25519 library you may find ed25519-dalek, and from there you could find curve25519-dalek which deals in point encodings and that like. (I don't know these particular libraries; they might help or just serve as an example of a viable exploration path).