sbin/grml-sniff

   1 #!/bin/sh
   2 # Filename:      grml-sniff
   3 # Purpose:       script for configuring a network sniffing setup
   4 # Authors:       grml-team (grml.org), (c) Michael Prokop <mika@grml.org>
   5 # Bug-Reports:   see http://grml.org/bugs/
   6 # License:       This file is licensed under the GPL v2.
   7 ################################################################################
   8
   9 CONFIG_FILE=/etc/grml/routersetup
  10 . /etc/grml/lsb-functions
  11 . /etc/grml/script-functions
  12
  13 usage_info()
  14 {
  15    einfo "$0 - script for configuring a network sniffing setup"
  16    einfo "Configure via $CONFIG_FILE - see man 8 grml-sniff" ; eend 0
  17 }
  18
  19 if [ -r "$CONFIG_FILE" ] ; then
  20   . "$CONFIG_FILE"
  21 else
  22   ewarn "Could not read $CONFIG_FILE"
  23 fi
  24
  25 # defaults if unconfigured
  26 [ -n "$BRCTL" ]          || BRCTL='brctl'
  27 [ -n "$BRIDGE_NAME" ]    || BRIDGE_NAME='br0'
  28 [ -n "$BRIDGE_DEVICES" ] || BRIDGE_DEVICES='eth0 eth1'
  29
  30 check_devs() {
  31   for dev in $BRIDGE_DEVICES ; do
  32     ip link show dev "$dev" >/dev/null 2>&1 || return 1
  33  done
  34 }
  35
  36 if ! check_devs ; then
  37   eerror "BRIDGE_DEVICES $BRIDGE_DEVICES do not seem to exist." >&2
  38   exit 1
  39 fi
  40
  41 check4progs $BRCTL || exit 1
  42
  43 case "$1" in
  44     start)
  45         check4root || exit 1
  46         einfo "Starting sniffing setup"
  47         eindent
  48
  49             einfo "Creating bridge device"
  50             brctl addbr "$BRIDGE_NAME"
  51             eend $?
  52
  53             einfo "Bringing network device in promiscuous mode up:"
  54             eindent
  55                for i in $BRIDGE_DEVICES ; do
  56                    einfo "$i"
  57                    ifconfig "$i" -arp promisc 0.0.0.0 up ; eend $?
  58                done
  59             eoutdent
  60
  61             einfo "Adding network devices to $BRIDGE_NAME:"
  62             eindent
  63             for i in $BRIDGE_DEVICES ; do
  64                 einfo "$i"
  65                 brctl addif "$BRIDGE_NAME" $i  ; eend $?
  66             done
  67             eoutdent
  68
  69             einfo "Bringing bridge $BRIDGE_NAME in promiscuous up"
  70             ip link set "$BRIDGE_NAME" promisc on up ; eend $?
  71         eoutdent
  72    ;;
  73
  74    stop)
  75         check4root || exit 1
  76         einfo "Stopping sniffing setup"
  77         eindent
  78             einfo "Removing network devices from $BRIDGE_NAME: "
  79
  80             eindent
  81                for i in $BRIDGE_DEVICES ; do
  82                    einfo "$i "
  83                    brctl delif "$BRIDGE_NAME" $i  ; eend $?
  84                done
  85             eoutdent
  86
  87             einfo "Disabling promiscuous mode on: "
  88             eindent
  89                for i in $BRIDGE_DEVICES ; do
  90                    einfo "$i "
  91                    ip link set "$i" promisc off ; eend $?
  92                done
  93             eoutdent
  94
  95             einfo "Bringing bridge $BRIDGE_NAME down"
  96             ip link set "$BRIDGE_NAME" down; eend $?
  97
  98             einfo "Removing bridge device $BRIDGE_NAME"
  99             ifconfig "$BRIDGE_NAME" down || /bin/true
 100             brctl delbr "$BRIDGE_NAME"
 101             eend $?
 102
 103         eoutdent
 104    ;;
 105
 106    restart)
 107         check4root || exit 1
 108         $0 stop
 109         sleep 1
 110         $0 start
 111    ;;
 112
 113    info|-h|--help)
 114         usage_info
 115    ;;
 116
 117    status)
 118         check4root || exit 1
 119         einfo "$0 - status:"
 120         $BRCTL show ; eend $?
 121    ;;
 122
 123    *)
 124         echo "Usage: $0 {start|stop|restart|status|info}"
 125         exit 1
 126    ;;
 127 esac
 128
 129 ## END OF FILE #################################################################
 130 # vim: ft=sh expandtab ai