#!/bin/bash # # contrary to ttcn3-tcpdump-start.sh, this version is dumpcap-only and # needed when we want to capture from interfaces of different link # types. It will also store the results as pcap-ng, not plain old pcap. PIDFILE_PCAP=/tmp/pcap.pid DUMPCAP=/usr/bin/dumpcap PIDFILE_NETCAT=/tmp/netcat.pid NETCAT=/bin/nc GSMTAP_PORT=4729 TESTCASE=$1 kill_rm_pidfile() { if [ -e $1 ]; then kill "$(cat "$1")" rm $1 fi } echo "------ $TESTCASE ------" date if [ "z$TTCN3_PCAP_PATH" = "z" ]; then TTCN3_PCAP_PATH=/tmp fi kill_rm_pidfile $PIDFILE_NETCAT kill_rm_pidfile $PIDFILE_PCAP if [ ! -x "$DUMPCAP" ]; then echo "Missing required dumpcap binary at ${DUMPCAP}" exit 31 fi if [ "$(id -u)" = "0" ]; then CMD="$DUMPCAP -q" else CAP_ERR="1" if [ -x /sbin/setcap ]; then # N. B: this check requires libcap2-bin package /sbin/setcap -q -v 'cap_net_admin,cap_net_raw=pie' $DUMPCAP CAP_ERR="$?" fi if [ -u $DUMPCAP -o "$CAP_ERR" = "0" ]; then CMD="$DUMPCAP -q" else echo "NOTE: unable to use dumpcap due to missing capabilities or suid bit" exit 32 fi fi # Create a dummy sink for GSMTAP packets $NETCAT -l -u -k -p $GSMTAP_PORT >/dev/null 2>$TESTCASE.netcat.stderr & PID=$! echo $PID > $PIDFILE_NETCAT # generate the list of interface arguments. For capturing from # interfaces of different link-layer types, we cannot use "-i all" # but must use dumpcap with each individual interface name. We also # must write pcapng files, as only those can record the interface of # each packet ADDL_ARGS="-i lo" for f in /sys/class/net/*; do DEV=`basename $f` if [[ "$DEV" == "hdlcnet"* ]]; then # skip these as we only want the hdlcX devices, avoid capturing twice on both sides continue elif [[ "$DEV" == "hdlc"* ]]; then # these are the user-side of the FR links, which is # what we interface with from our test suite, emulating # a BSS. ADDL_ARGS="${ADDL_ARGS} -i ${DEV}" elif [[ "$DEV" == "eth"* ]]; then # we blindly assume that "normal" docker network devices # are called ethXXX ADDL_ARGS="${ADDL_ARGS} -i ${DEV}" fi done $CMD -s 1520 -n ${ADDL_ARGS} -w "$TTCN3_PCAP_PATH/$TESTCASE.pcapng" >$TTCN3_PCAP_PATH/$TESTCASE.pcapng.stdout 2>&1 & PID=$! echo $PID > $PIDFILE_PCAP # Wait until packet dumper creates the pcap file and starts recording. # We generate some traffic until we see packet dumper catches it. # Timeout is 10 seconds. ping 127.0.0.1 >/dev/null 2>&1 & PID=$! i=0 while [ ! -f "$TTCN3_PCAP_PATH/$TESTCASE.pcapng" ] || [ "$(stat -c '%s' "$TTCN3_PCAP_PATH/$TESTCASE.pcapng")" -eq 32 ] do echo "Waiting for packet dumper to start... $i" sleep 1 i=$((i+1)) if [ $i -eq 10 ]; then break fi done kill $PID