I'm curious, what do you actually use it for?

I'd have otherwise guessed that this tool mainly exists just to test lib25519. Personally I'd only ever want a library, or some higher-level tool. A CLI tool that just does raw signing feels like a weird (and footgun-shaped) middle ground.

I was wondering the same thing. My best guess is that is to guard against operator misuse. Like usb-a only plugging in one way. Anything that is secret will never accidentally print to stdout. String interpolation in bash with `—option $empty` might be safer than `8<$empty`. Have to explore more but yeah, this is a new pattern for me as well.

What a strange convention. I'm partial to minisign, which works on plain old files.

That's such a user-hostile design decision. I can't fathom what justifies it (other than kinky taste).

Makes your commands unreadable without a manual, leaves a lot of room for errors that are quietly ignored. And forces you into using a shell that comes with its own set of gotchas, bash is not known to be a particularly good tool for security.

And to those who stay this adds flexibility: it doesn't. Those file descriptors are available under/dev/fd on linux, with named options you can do --pk /dev/fd/5. Or make a named pipe.

It's djb's web site so it's a djb design. With great genius comes great different thinking.

I’m guessing it’s to support the test framework it’s built with?

If you mean the OpenSSL CLI, it's hard to think of a more footgun-y cryptographic tool than the one that:

* defaults to unauthenticated encryption

* buries its one authenticated mode

* requires explicit command-line nonces

* defaults to an MD5 KDF

You could probably keep going for another 10 bullets. Never use the OpenSSL CLI for anything other than TLS stuff.

Short of suspecting a malicious tarball, I really can't think of a reason why "publish[ing] their code on an independent third-party public code sharing platform" would be a selling point. You're getting the source code straight from the horse's mouth this way.

The Download link in the header (https://lib25519.cr.yp.to/download.html).