#!/bin/bash
#
# Copyright 2014-2023 Security Onion Solutions, LLC
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.


# This script returns the average of all the workers average capture loss to telegraf / influxdb in influx format include nanosecond precision timestamp

# if this script isn't already running
if [[ ! "`pidof -x $(basename $0) -o %PPID`" ]]; then

    if [ -d "/host/nsm/zeek/spool/logger" ]; then
      WORKERS={{ salt['pillar.get']('sensor:zeek_lbprocs', salt['pillar.get']('sensor:zeek_pins') | length) }}
      ZEEKLOG=/host/nsm/zeek/spool/logger/capture_loss.log
    elif [ -d "/host/nsm/zeek/spool/zeeksa" ]; then
      WORKERS=1
      ZEEKLOG=/host/nsm/zeek/spool/zeeksa/capture_loss.log
    else
      echo 'Zeek capture_loss.log not found' >/dev/stderr
      exit 2
    fi

    LASTCAPTURELOSSLOG=/var/log/telegraf/lastcaptureloss.txt
    if [ -f "$ZEEKLOG" ]; then
      CURRENTTS=$(tail -1 $ZEEKLOG | jq .ts | sed 's/"//g')
      if [ -f "$LASTCAPTURELOSSLOG" ]; then
        LASTTS=$(cat $LASTCAPTURELOSSLOG)
        if [[ "$LASTTS" != "$CURRENTTS" ]]; then
          LOSS=$(tail -$WORKERS $ZEEKLOG | awk -F, '{print $NF}' | sed 's/}//' | awk -v WORKERS=$WORKERS -F: '{LOSS += $2 / WORKERS} END { print LOSS}')
          echo "zeekcaptureloss loss=$LOSS"
        fi
      fi
      echo "$CURRENTTS" > $LASTCAPTURELOSSLOG
    fi

fi

exit 0