#!/bin/bash
export KRB5CCNAME=/tmp/krb5cc_$(id -u).root
export KRBTKFILE=/dev/null

lifetime=900
hostopt=""
[ -z "$hostopt" ] && hostopt="${HOSTNAME}"
[ -z "$hostopt" ] && hostopt=`uname -n 2>/dev/null || echo unknown`
keys=~/.ssh/id_rsa_root

function with-keys
{
    unset SSH_AUTH_SOCK SSH_AGENT_PID
    eval $(keychain --eval --host "$hostopt-root")
    exec "$@"
}

case $1 in
    init)
        shift;
        unset SSH_AUTH_SOCK SSH_AGENT_PID
        echo exec keychain --host "$hostopt-root" $keys
        ;;
    add)
        with-keys ssh-add -t $lifetime "$@"
        ;;
    destroy)
        with-keys ssh-add -D
        ;;
    shell)
        HOSTNAME="`hostname` (sshroot)" with-keys $SHELL
        ;;
    ssh)
        shift
        with-keys ssh -l root "$@"
        ;;
    *)
        if [ $# = 0 ]; then
            echo "Usage: $0 init" >&2
            echo "       $0 add" >&2
            echo "       $0 destroy" >&2
            echo "       $0 shell" >&2
            echo "       $0 ssh [args]" >&2
            echo "       $0 [cmd]" >&2
        else
            with-keys "$@"
        fi
        ;;
esac