Is there a one liner which can list public key fingerprints with authorized_keys as input?

Question

I'd like to audit the authorized_keys file on a number of servers and match them with known AWS key fingerprints.

Is there a one-liner which incorporates ssh-keygen -lf which will output the fingerprint of every key in an authorized_keys file in a nice list with line breaks?

Answer 1

From serverfault:

You can easily make it a function in your .bashrc:

function fingerprints() {
  local file="$1"
  while read l; do
    [[ -n $l && ${l###} = $l ]] && ssh-keygen -l -f /dev/stdin <<<$l
  done < $file
}

and then do:

$ fingerprints .ssh/authorized_keys

Answer 2

Here you go:

    find /path/to/keys/directory -type f -name "*.pub" -exec ssh-keygen -lf {} \; | awk '{print $2}'

Edit: Whops, ok. get it now.

here you go:

    while read line; do ssh-keygen -lf "$line"; done < <(cat authorised_keys_file)

(if this file have one key per line)