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README.adoc

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+= cc20p1305ssh
+Brent Saner <bts@square-r00t.net>
+Last updated {localdatetime}
+:doctype: book
+:docinfo: shared
+:data-uri:
+:imagesdir: images
+:sectlinks:
+:sectnums:
+:sectnumlevels: 7
+:toc: preamble
+:toc2: left
+:idprefix:
+:toclevels: 7
+:source-highlighter: rouge
+
+== What is it?
+
+A Golang library variant of ChaCha20-Poly1305 that OpenSSH uses (`chacha20-poly1305@openssh.com`).
+
+Note that this module *only* supports the OpenSSH variant, and should only be used for key generation/parsing/modification/manipulation, not actual connection/stream encryption.
+
+== Why is this necessary?
+
+Because Golang.org/x/crypto https://github.com/golang/go/issues/36646[removes functionality^] (even for https://github.com/golang/go/issues/44226[very common tech^]) and thinks OpenSSH is a "weird" use case. That's a direct reference; they called it "weird".
+
+I *really, really* hope this library is https://github.com/golang/go/issues/57699[no longer necessary^] by the time I'm done writing it but based on my past experiences with core Golang devs, my expectations are extremely low.
+
+They have no decent support for OpenSSH keys or lower-level operations. And guess what -- sometimes you *need* lower-level functionality. Who knew?
+
+So now because I'm just a single individual, bug fixes will probably lag behind upstream. All because Golang devs decided the OpenSSH variant was "too weird".
+
+But, of course, not "weird" enough to https://github.com/golang/crypto/blob/3d872d042823aed41f28af3b13beb27c0c9b1e35/ssh/cipher.go#L652[not support the *wire* protocol^] for SSH. Just the key encryption. Because of course. And not publicly exposed either. Because *of course*.
+
+Assholes.
+
+== Why is the name so ugly?
+
+I couldn't think of a better one and I wanted something notably distinct from the stdlib-x naming.
+
+And module names can't include the `@` symbol.
+
+== Why don't you expose the rest of ChaCha20/Poly1305/ChaCha20-Poly1305?
+
+* To keep code changes from upstream light (and thus easier to debug, audit, etc.)
+* Because otherwise the module name is inaccurate
+** Because OpenSSH has their own specific variant
+** Which means we can handle SSH-specific functionality if needed
+* Because golang/x/crypto has made it painfully clear that if you want something that deviates from what they *think* is "best practice", you need to do it yourself
+** Which ironically is something they also brand an "anti-pattern" which is just \*chef's kiss*