[c-nsp] SSH public key authentication

Phil Mayers p.mayers at imperial.ac.uk
Thu Feb 25 07:15:29 EST 2016

On 25/02/16 11:11, Tom Storey wrote:
> Playing with public key authentication on a 1811, and it seems that
> when trying to paste in my public key, it wont accept more than 254
> characters.
> The public key is longer than 254 characters, however.

Just enter the hash.

> How does one go about entering more than 254 characters? Im sure Im
> missing something really simple here, like a control character
> sequence to allow more text to be entered on a following line
> perhaps....?
> Ive noticed that you can also use a hash instead of the full key text,
> and this is working just fine. Are there any concerns using the hash
> instead of full key text?

It converts a key to a hash anyway IME, so no - you get the exact same 

You can get the hash from a Unix box with:

ssh-keygen  -l -f $KEY | awk '{ print $2 }' | sed -e 's/://g'

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