webpki VS sign-cert-remote

Beyond that, various things like the ScyllaDB driver are using OpenSSL because WebPKI doesn't support validating connections to IP addresses (as opposed to DNS names) and RusTLS currently delegates to WebPKI.

There's a JIT framework in Rust: https://github.com/bytecodealliance/wasmtime

There's a library for doing full X.509 certificate parsing and verification: https://briansmith.org/rustdoc/webpki/

There's definitely some attempts at doing pure-Rust SSL, but I suspect a lot of them are also doing some sketchy things with crypto that shouldn't be trusted (getting constant-time stuff implemented properly is really challenging, and probably requires large amounts of assembly to guarantee correctness).

An issue was raised with webpki to support the IP addressees 5 years ago, and yet it's still not there. What do people use to overcome the fact that rustls can't do IP-based client connections because of it? My guess would be, they are switching to native-tls or openssl-tls.

Yes, rustls currently doesn't support certificates without hostnames (only an IP); this is actually an issue with the webpki crate, and work to solve it is ongoing (will hopefully land in a release in a few months or so).

> Bundling this set with Firefox

I love that they did that; it was actually my idea (https://bugzilla.mozilla.org/show_bug.cgi?id=657228). I believe the list is pretty large and changes frequently and so they download it dynamically.

> short cut to a "Yes"

Do they really do that? That's awesome if so. Then they don't even need to ship the roots.

> I specifically don't like [...] saying "unknown issuer"

https://github.com/briansmith/webpki/issues/221

> If std::fs::File::open() gives me Result with an io:Error that claims "File not found" but the underlying OS file open actually failed due to a permission error, you can see why that's a problem right? Even if this hypothetical OS doesn't expose any specific errors, "File not found" is misleading.

A more accurate analogy: You ask to open "example.txt" without supplying the path, and there is no "example.txt" in the current working directory. You will get "file not found."

Regardless, I agree we could have a better name than UnknownIssuer for this error.

rustls definitely does support self-signed certificates, but it makes it somewhat harder to use to prevent users from shooting themselves in the foot trusting certificates that should not be trusted. I've used the rcgen crate in the past to work with self-signed certificates, some example code is here: https://github.com/djc/sign-cert-remote/blob/main/src/main.rs.