x/crypto/ssh: MarshalAuthorizedKey discards comment

[dpogorzelski]

What version of Go are you using (go version)?

1.16

Does this issue reproduce with the latest release?

yes

What operating system and processor architecture are you using (go env)?

go env Output

GOHOSTARCH="amd64"
GOHOSTOS="darwin"

Hello, it seems like https://github.com/golang/crypto/blob/master/ssh/keys.go#L281 will never consider writing the comment of the key so when parsing such key later on via https://github.com/golang/crypto/blob/master/ssh/keys.go#L85 the comment value will always be empty.

[dpogorzelski]

Please also notice that the https://github.com/golang/crypto/blob/master/ssh/keys.go#L293 interface has a method to retrieve the key type but not the comment

[toothrot]

/cc @FiloSottile