Script to NMAP a network and Post Differences to Slack

slackmap.sh

#!/bin/sh
TARGETS="192.168.1.0/24"
OPTIONS="-v -T4 -F -sV"
date=$(date +%Y-%m-%d-%H-%M-%S)
cd /nmap/diffs
nmap $OPTIONS $TARGETS -oA scan-$date > /dev/null
slack(){
curl -F file=@diff-$date -F initial_comment="Internal Port Change Detected" -F channels=#alerts -F token=xxxx-xxxx-xxxx https://slack.com/api/files.upload
}

if [ -e scan-prev.xml ]; then
ndiff scan-prev.xml scan-$date.xml > diff-$date
[ "$?" -eq "1" ] && sed -i -e 1,3d diff-$date && slack
fi
ln -sf scan-$date.xml scan-prev.xml