ssh-copy-id replacement to copy only if key auth fails

ssh-copy-id-if-needed.sh

#!/bin/bash
########################################################################################
## ssh-copy-id-if-needed
## 
## Copies specified identity file to specified server
##

usage() {
	echo "usage: $0 [-i [identity_file]] [user@]machine" >&2
	exit 1
}

IDENTITY_FILE=""

while getopts “hi:” OPTION
do
	case $OPTION in
		 h)
			 usage
			 ;;
		 i)
			 IDENTITY_FILE="${OPTARG}"
			 ;;
		 ?)
			 usage
			 ;;
	 esac
done

REMOTE_HOST="${@:$OPTIND:1}"

if [[ "${IDENTITY_FILE}" == "" ]]; then
	usage
fi

# echo "IDENTITY_FILE: ${IDENTITY_FILE}"
# echo "REMOTE_HOST: ${REMOTE_HOST}"

SSH_AUTH_SOCK=/dev/null ssh -o "BatchMode yes" -i "${IDENTITY_FILE}" "${REMOTE_HOST}" uptime > /dev/null 2> /dev/null
RV=${?}
if [[  ${RV} != 255 ]]; then
	echo "error: Key may already be on server (RV not 255)" >&2
	exit 99
fi

GET_ID="$(cat "${IDENTITY_FILE}")"
{ echo "${GET_ID}" ; } | ssh ${REMOTE_HOST} -i "${IDENTITY_FILE}" "umask 077; test -d .ssh || mkdir .ssh ; cat >> .ssh/authorized_keys" || exit 1