SSH RE-KEY

gistfile1.txt

#!/bin/bash

# Shell script to install your public key on a remote machine
# Takes the remote machine name as an argument.
# The remote machine must accept password authentication,
# one of the other keys in your ssh-agent, 
# or accept the key passed with the Identity (-i) flag for this to work.


# -f : public identity to copy to the known_hosts file
# -i : private key to use to connect to the server

SSH_OPS=""

ID_FILE="${HOME}/.ssh/id_rsa.pub"

usage() { echo -e "Usage: ssh-rekey-id [-f <STRING>] [-i <STRING>] [USERID@]HOSTNAME\n -f <STRING> for pub key file\n -i <STRING> for ssh identy file";}


while getopts "f:i:h:" opt; do
        case "${opt}" in
        f)
                ID_FILE=${OPTARG}
                ;;
        i)
                SSH_OPS="${SSH_OPS} -i${OPTARG}"
                ;;
        h|\?)
                usage
                exit 1
                ;;
        esac
done
shift $((OPTIND-1))
if [ -z "$1" ]; then
        usage
        exit 1
else
        # strip any trailing colon
        HOST=`echo $1 | sed 's/:$//'`
fi
if [ -r "${ID_FILE}" ] ; then
  GET_ID="cat ${ID_FILE}"
fi

if [ -z "`eval ${GET_ID}`" ]; then
  echo ${ID_FILE}
  echo "$0: ERROR: No identities found" >&2
  exit 1
fi

#echo ' ssh ${SSH_OPS} ${HOST} "umask 077; test -d ~/.ssh || mkdir ~/.ssh ; cat >> ~/.ssh/authorized_keys" '
{ eval "${GET_ID}" ; } | ssh ${SSH_OPS} ${HOST} "umask 077; test -d ~/.ssh || mkdir ~/.ssh ; cat >> ~/.ssh/authorized_keys" || exit 1


cat <<EOF
Now try logging into the machine, with "ssh '${HOST}'", and check in:

  ~/.ssh/authorized_keys

to make sure we haven't added extra keys that you weren't expecting.

EOF