#!/bin/sh # Copyright (c) 2011 Rozhuk Ivan <rozhuk.im@gmail.com> # All rights reserved. # # Subject to the following obligations and disclaimer of warranty, use and # redistribution of this software, in source or object code forms, with or # without modifications are expressly permitted by Whistle Communications; # provided, however, that: # 1. Any and all reproductions of the source or object code must include the # copyright notice above and the following disclaimer of warranties; and # 2. No rights are granted, in any manner or form, to use Whistle # Communications, Inc. trademarks, including the mark "WHISTLE # COMMUNICATIONS" on advertising, endorsements, or otherwise except as # such appears in the above copyright notice or in the software. # # THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND # TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO # REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, # INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF # MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. # WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY # REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS # SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. # IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES # RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING # WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, # PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR # SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF # THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY # OF SUCH DAMAGE. # # Author: Rozhuk Ivan <rozhuk.im@gmail.com> # # This script creates bridge between two network interfaces # downstream - network with clients # upstream - network with multicast # downstream <-IGMP-> upstream # downstream <-UDP<- upstream # Only packets with multicast destination mac address are forwarded # through the bridge and (!) are not passed to network stack IF_UPSTREAM="$2" IF_DOWNSTREAM="$3" BR_NAME="${IF_UPSTREAM}-${IF_DOWNSTREAM}-br" PATTERN_MCAST_IGMP="ether[0] & 1 = 1 and (ether[0:4] != 0xffffffff or ether[4:2] != 0xffff) and ip[9] = 2" PATTERN_MCAST_IGMP_UDP="ether[0] & 1 = 1 and (ether[0:4] != 0xffffffff or ether[4:2] != 0xffff) and (ip[9] = 17 or ip[9] = 2)" # allways NOT MATCH BPFPROG_PASSTROUTH="bpf_prog_len=1 bpf_prog=[ { code=6 jt=0 jf=0 k=0 } ]"
usage_msg() { echo "usage: start|stop upstreamIF downstreamIF" echo "This will create bridge between two interfaces for IGMP, and UDP from upstreamIF to downstreamIF" } if [ -z "${IF_UPSTREAM}" -o -z "${IF_DOWNSTREAM}" ]; then usage_msg return 1 fi if ! ifconfig "$IF_UPSTREAM" > /dev/null 2>&1 ; then usage_msg echo "Invalid upstream interface: ${IF_UPSTREAM}" return 1 fi if ! ifconfig "$IF_DOWNSTREAM" > /dev/null 2>&1 ; then usage_msg echo "Invalid downstream interface: ${IF_DOWNSTREAM}" return 1 fi case "$1" in start) echo "start bridging beetwen ${IF_UPSTREAM} and ${IF_DOWNSTREAM}" # load modules kldload ng_ether > /dev/null 2>&1 kldload ng_bpf > /dev/null 2>&1 BPFPROG_MCAST_IGMP=$( tcpdump -s 65535 -ddd ${PATTERN_MCAST_IGMP} | \ ( read len ; \ echo -n "bpf_prog_len=$len " ; \ echo -n "bpf_prog=[" ; \ while read code jt jf k ; do \ echo -n " { code=$code jt=$jt jf=$jf k=$k }" ; \ done ; \ echo " ]" ) ) BPFPROG_MCAST_IGMP_UDP=$( tcpdump -s 65535 -ddd ${PATTERN_MCAST_IGMP_UDP} | \ ( read len ; \ echo -n "bpf_prog_len=$len " ; \ echo -n "bpf_prog=[" ; \ while read code jt jf k ; do \ echo -n " { code=$code jt=$jt jf=$jf k=$k }" ; \ done ; \ echo " ]" ) ) # create and connect nodes ngctl mkpeer ${IF_UPSTREAM}: bpf lower ${IF_UPSTREAM}-lower ngctl name ${IF_UPSTREAM}:lower ${BR_NAME}-bpf ngctl connect ${IF_UPSTREAM}: ${BR_NAME}-bpf: upper ${IF_UPSTREAM}-upper ngctl connect ${IF_DOWNSTREAM}: ${BR_NAME}-bpf: lower ${IF_DOWNSTREAM}-lower ngctl connect ${IF_DOWNSTREAM}: ${BR_NAME}-bpf: upper ${IF_DOWNSTREAM}-upper # configure BPF node ngctl msg ${BR_NAME}-bpf: setprogram { thisHook=\"${IF_UPSTREAM}-lower\" ifMatch=\"${IF_DOWNSTREAM}-lower\" ifNotMatch=\"${IF_UPSTREAM}-upper\" ${BPFPROG_MCAST_IGMP_UDP} } ngctl msg ${BR_NAME}-bpf: setprogram { thisHook=\"${IF_UPSTREAM}-upper\" ifMatch=\"\" ifNotMatch=\"${IF_UPSTREAM}-lower\" ${BPFPROG_PASSTROUTH} } ngctl msg ${BR_NAME}-bpf: setprogram { thisHook=\"${IF_DOWNSTREAM}-lower\" ifMatch=\"${IF_UPSTREAM}-lower\" ifNotMatch=\"${IF_DOWNSTREAM}-upper\" ${BPFPROG_MCAST_IGMP} } ngctl msg ${BR_NAME}-bpf: setprogram { thisHook=\"${IF_DOWNSTREAM}-upper\" ifMatch=\"\" ifNotMatch=\"${IF_DOWNSTREAM}-lower\" ${BPFPROG_PASSTROUTH} } # configure net if ngctl msg ${IF_UPSTREAM}: setautosrc 1 ngctl msg ${IF_UPSTREAM}: setpromisc 1 #ngctl msg ${IF_DOWNSTREAM}: setautosrc 0 ngctl msg ${IF_DOWNSTREAM}: setpromisc 1 ;; stop) echo "stop bridging beetwen ${IF_UPSTREAM} and ${IF_DOWNSTREAM}" # configure net if ngctl msg ${IF_UPSTREAM}: setautosrc 0 ngctl msg ${IF_UPSTREAM}: setpromisc 0 #ngctl msg ${IF_DOWNSTREAM}: setautosrc 0 ngctl msg ${IF_DOWNSTREAM}: setpromisc 0 # remove hooks and nodes ngctl rmhook ${IF_UPSTREAM}: lower ngctl rmhook ${IF_UPSTREAM}: upper ngctl rmhook ${IF_DOWNSTREAM}: lower ngctl rmhook ${IF_DOWNSTREAM}: upper ngctl shutdown ${BR_NAME}-bpf: # unload modules #kldunload ng_ether > /dev/null 2>&1 #kldunload ng_bpf > /dev/null 2>&1 ;; *) usage_msg esac return 0 | 
