authkeys-report - create a table with ssh keys type/strength/finger print from authorized_keys. no known licence, copied from http://unix.stackexchange.com/questions/2116/given-keys-in-ssh-authorized-keys-format-can-you-determine-key-strength-easi

authkeys-report

#!/bin/sh

# usage: authkeys-report <authorized_keys-file>

set -ue

tmp="$(mktemp -t fingerprint-authkeys.XXXXXXXX)"
trap 'rm -f "$tmp"' 0

while read opts key; do
    case "$opts" in
        [0-9]*|ssh-dss|ssh-rsa)
            # not options, first "word" is part of key
            key="$opts $key"
        ;;
    esac
    echo "$key" >$tmp
    set -- $(ssh-keygen -lf "$tmp")
    bits="$1" fingerprint="$2"

    set -- $key # Note: will mangle whitespace in the comment
    case "$1" in
        [0-9]*) # SSH v1 key
            type=rsa1
            shift 3
        ;;
        ssh-rsa|ssh-dss) # SSH v2 key
            type="$1"
            shift 2
        ;;
        *)
            type=unknown
            set --
        ;;
    esac

    printf '%-14s %-9s %s %s\n' "$type" "$bits" "$fingerprint" "$*"
done <$1

I believe ssh-keygen -l produces MD5 fingerprints, not SHA1 fingerprints. So if you need SHA1, this won't do it.

On Wed, Mar 14, 2012 at 8:39 PM, Shawn Willden ***@***.*** wrote: I believe ssh-keygen -l produces MD5 fingerprints, not SHA1 fingerprints.  So if you need SHA1, this won't do it. --- Reply to this email directly or view it on GitHub: https://gist.github.com/2001086

Mmh true the fingerprint seems top be MD5. I blindly copied the info from the stack exchange page without checking. I've just edited the gist presentation to remove mention of the hashing protocol to correct that. Cheers Gildas