passless-auth

#!/bin/bash

debug=false

user=$USER
key_path=~/.ssh/id_ecdsa.pub

function usage()
{
cat << _EOF_
usage:
 $(basename $0) -u [USER] -h [HOST IP] -p [SSH KEY PATH]

arguments:
 -u     Login User
 -h     Host IP Address
 -p     SSH Key File Path

_EOF_
exit
}

function add_key()
{
    remote=$user@$host
    cat $key_path | ssh -o StrictHostKeyChecking=no $remote "
        mkdir -p ~/.ssh
        chmod 700 ~/.ssh
        cat >> ~/.ssh/authorized_keys
        sort -u ~/.ssh/authorized_keys > ~/.ssh/authorized_keys.bak
        mv ~/.ssh/authorized_keys.bak ~/.ssh/authorized_keys
        chmod 600 ~/.ssh/authorized_keys
    "
    ssh -n -o PasswordAuthentication=no $remote true
}

while getopts ":u:h:p:" opt;
do
    case $opt in
        u)
            user=${OPTARG}
            ;;
        h)
            host=${OPTARG}
            ;;
        p)
            key_path=${OPTARG}
            ;;
        *)
            break
            ;;
    esac
done

if [ $OPTIND -eq 0 ] || [ -z "$user" ] || [ -z "$host" ] || [ -z "$key_path" ]
then
    usage
fi

add_key