#! /bin/sh
#  ipscan - scan IP network for non-DNS listed hosts using PING
#  usage:    ipscan  domain       class-C-subnet
#  example:  ipscan  wr.usgs.gov  130.118.25
#  Rex Sanders, USGS, 8/24/94

# Get current list of DNS-registered hosts
echo "ls $1" | /usr/etc/nslookup | \
grep " $2"'\.[0-9][0-9]*$' | \
    sed -e 's/^ .*  '"$2"'\./'"$2"'./' | \
    sort -u > /tmp/ipscan1.$$

# Generate list of all possible Class C addresses
awk 'END {i=1; while (i<=254) {printf "'"$2"'.%d\n", i; i++}}' < /dev/null | \
   sort > /tmp/ipscan2.$$

# Generate list of non-DNS-registered addresses
comm -13 /tmp/ipscan1.$$ /tmp/ipscan2.$$ | sort -t. +2 -3n +3n > /tmp/ipscan3.$$

rm -f /tmp/ipscan1.$$ /tmp/ipscan2.$$

# Ping each non-DNS-registered address
for i in `cat /tmp/ipscan3.$$`
do
  /usr/etc/ping -s $i 56 1 | fgrep "bytes from $i"
done

rm /tmp/ipscan3.$$