Angenommen wir haben einen "RootServer" im Internet
mit der WAN IP: 1.2.3.4
Dort lassen wir das Programm: ptunnel und Squid laufen.
# apt-get install ptunnel
startscript
/etc/init.d/ptunnel
#! /bin/sh
### BEGIN INIT INFO
# Provides: ptunnel
# Required-Start: $remote_fs $network $syslog
# Required-Stop: $remote_fs $network $syslog
# Default-Start: 2 3 4 5
# Default-Stop: 0 1 6
# Short-Description: initscript for ptunnel
# Description: initscript for ptunnel
### END INIT INFO
# Do NOT "set -e"
# PATH should only include /usr/* if it runs after the mountnfs.sh script
PATH=/sbin:/usr/sbin:/bin:/usr/bin
DESC="IP over ICMP tunneling server"
NAME=ptunnel
DAEMON=/usr/sbin/$NAME
DEFAULT=ptunnel
DAEMON_ARGS=""
PIDFILE=/var/run/$NAME.pid
SCRIPTNAME=/etc/init.d/$NAME
# Exit if the package is not installed
[ -x "$DAEMON" ] || exit 0
# Load the VERBOSE setting and other rcS variables
. /lib/init/vars.sh
# Define LSB log_* functions.
# Depend on lsb-base (>= 3.0-6) to ensure that this file is present.
. /lib/lsb/init-functions
# Get config
get_config() {
[ -r /etc/default/$DEFAULT ] && . /etc/default/$DEFAULT
if [ "$run_daemon" != "true" ] ; then
[ "$VERBOSE" != no ] && log_progress_msg "- automatic start disabled" && log_end_msg 0
exit 0
fi
}
#
# Function that starts the daemon/service
#
do_start()
{
# populate $DAEMON_ARGS
get_config
#
# Return
# 0 if daemon has been started
# 1 if daemon was already running
# 2 if daemon could not be started
start-stop-daemon --start --quiet --exec $DAEMON --test > /dev/null \
|| return 1
start-stop-daemon --start --quiet --background --exec $DAEMON -- -x "" -m 200\
|| return 2
# Add code here, if necessary, that waits for the process to be ready
# to handle requests from services started subsequently which depend
# on this one. As a last resort, sleep for some time.
}
#
# Function that stops the daemon/service
#
do_stop()
{
# Return
# 0 if daemon has been stopped
# 1 if daemon was already stopped
# 2 if daemon could not be stopped
# other if a failure occurred
start-stop-daemon --stop --quiet --retry=TERM/5/KILL/5 --exec $DAEMON
RETVAL="$?"
[ "$RETVAL" = 2 ] && return 2
# Wait for children to finish too if this is a daemon that forks
# and if the daemon is only ever run from this initscript.
# If the above conditions are not satisfied then add some other code
# that waits for the process to drop all resources that could be
# needed by services started subsequently. A last resort is to
# sleep for some time.
start-stop-daemon --stop --quiet --oknodo --retry=0/5/KILL/5 --exec $DAEMON
[ "$?" = 2 ] && return 2
# Many daemons don't delete their pidfiles when they exit.
rm -f $PIDFILE
return "$RETVAL"
}
case "$1" in
start)
[ "$VERBOSE" != no ] && log_daemon_msg "Starting $DESC" "$NAME"
do_start
case "$?" in
0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
esac
;;
stop)
[ "$VERBOSE" != no ] && log_daemon_msg "Stopping $DESC" "$NAME"
do_stop
case "$?" in
0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
esac
;;
restart|force-reload)
log_daemon_msg "Restarting $DESC" "$NAME"
do_stop
case "$?" in
0|1)
do_start
case "$?" in
0) log_end_msg 0 ;;
1) log_end_msg 1 ;; # Old process is still running
*) log_end_msg 1 ;; # Failed to start
esac
;;
*)
# Failed to stop
log_end_msg 1
;;
esac
;;
*)
echo "Usage: $SCRIPTNAME {start|stop|restart|force-reload}" >&2
exit 3
;;
esac
# update-rc.d ptunnel defaults
# /etc/init.d/ptunnel start
Auf dem Client ptunnel installieren oder kompilieren
# ./ptunnel -m 30 -p 1.2.3.4 -lp 8000 -da localhost -dp 3128 -c eth0 -x
Dann auf dem Client im Browser folgenden Proxy eintragen
Host: localhost Port:8000
So kann man aus einem Netzwerk das einen Ping ins internet zulässt aber
keinen Zugriff per HTTP / HTTPs / FTP über einen ICMP Tunnel über
den Proxy auf dem "RootServer" doch surfen.