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 "$1" in
  44     start)
  45         check4root || exit 1
  46         einfo "Starting sniffing setup"
  47         eindent
  48             einfo "Creating bridge device"
  49             brctl addbr "$BRIDGE_NAME"
  50             eend $?
  51
  52             einfo "Bringing network device in promiscuous mode up:"
  53             eindent
  54                for i in $BRIDGE_DEVICES ; do
  55                    einfo "$i"
  56                    ifconfig "$i" -arp promisc 0.0.0.0 up ; eend $?
  57                done
  58             eoutdent
  59
  60             einfo "Adding network devices to $BRIDGE_NAME:"
  61             eindent
  62             for i in $BRIDGE_DEVICES ; do
  63                 einfo "$i"
  64                 brctl addif "$BRIDGE_NAME" $i  ; eend $?
  65             done
  66             eoutdent
  67
  68             einfo "Bringing bridge $BRIDGE_NAME in promiscuous up"
  69             ip link set "$BRIDGE_NAME" promisc on up ; eend $?
  70         eoutdent
  71    ;;
  72
  73    stop)
  74         check4root || exit 1
  75         einfo "Stopping sniffing setup"
  76         eindent
  77             einfo "Removing network devices from $BRIDGE_NAME: "
  78
  79             eindent
  80                for i in $BRIDGE_DEVICES ; do
  81                    einfo "$i "
  82                    brctl delif "$BRIDGE_NAME" $i  ; eend $?
  83                done
  84             eoutdent
  85
  86             einfo "Disabling promiscuous mode on: "
  87             eindent
  88                for i in $BRIDGE_DEVICES ; do
  89                    einfo "$i "
  90                    ip link set "$i" promisc off ; eend $?
  91                done
  92             eoutdent
  93
  94             einfo "Bringing bridge $BRIDGE_NAME down"
  95             ip link set "$BRIDGE_NAME" down; eend $?
  96
  97             einfo "Removing bridge device $BRIDGE_NAME"
  98             ifconfig "$BRIDGE_NAME" down || /bin/true
  99             brctl delbr "$BRIDGE_NAME"
 100             eend $?
 101         eoutdent
 102    ;;
 103
 104    restart)
 105         check4root || exit 1
 106         $0 stop
 107         sleep 1
 108         $0 start
 109    ;;
 110
 111    info|-h|--help)
 112         usage_info
 113    ;;
 114
 115    status)
 116         check4root || exit 1
 117         einfo "$0 - status:"
 118         $BRCTL show ; eend $?
 119    ;;
 120
 121    *)
 122         echo "Usage: $0 {start|stop|restart|status|info}"
 123         exit 1
 124    ;;
 125 esac
 126
 127 ## END OF FILE #################################################################
 128 # vim: ft=sh expandtab ai