ssh-keygen -Z

[Benjamin Kaduk]

On Sun, 16 Feb 2014, Ruslan Makhmatkhanov wrote:

> Hello,
>
> there is -Z parameter in ssh-keygen --help output, but no mention of it in 
> ssh-keygen's man-page. Any clue what values this parameter accept?

It is the "new-format ciphername", which can be used for RSA keys if the 
new format file is being used, and is used for the elliptic curve keys, if 
I'm reading things correctly. I guess that would mean that it accepts 
things like "chacha20-poly1305 at openssh.com" and "aes256-ctr" (see the 
table ciphers[] in cipher.c), though I don't know which ones make sense to 
pass in there.

I guess we should ask the OpenBSD folks to document it, the -Z argument 
was added to ssh-keygen.c in r1.237 back in December.

-Ben