#!/bin/sh -
#
#   Reads /usr/local/arpwatch/arp.dat and displays a history.
#   Works with arpwatch (/usr/ports/net/arpwatch on FreeBSD).
#
#   Oliver Fromme  <olli@fromme.com>
#   This is free software.  BSD-style license applies (no GPL).
#

ARPDAT="/usr/local/arpwatch/arp.dat"
ETHDAT="/usr/local/arpwatch/ethercodes.dat"

DO_DATE=0
DO_VEND=1

while [ $# -gt 0 ]; do case "$1" in
	-d)
		DO_DATE=$((1 - $DO_DATE))
		shift
		;;
	-v)
		DO_VEND=$((1 - $DO_VEND))
		shift
		;;
	-dv|-vd)
		DO_DATE=$((1 - $DO_DATE))
		DO_VEND=$((1 - $DO_VEND))
		shift
		;;
	*)
		ME=`basename "$0"`
		echo "Usage: $ME [-d] [-v]" >&2
		echo "-d   toggle display of date/time stamps" >&2
		echo "-v   toggle display of vendors" >&2
		exit 1
		;;
esac; done

export ETHDAT DO_DATE DO_VEND

sort -n -k 3 "$ARPDAT" \
| awk '

BEGIN {
	zeit = "";
	vendor = "";
	ethdat = ENVIRON["ETHDAT"];
	do_date = ENVIRON["DO_DATE"];
	do_vend = ENVIRON["DO_VEND"];
	columns = ENVIRON["COLUMNS"];
	if (!columns || columns < 80)
		columns = 80;

	if (do_vend)
		while ((getline < "'"$ETHDAT"'") > 0) {
			e = tolower($1);
			n = $0;
			sub(/^[^ 	]*[ 	]*/, "", n);
			gsub(/[	 ][ 	]+/, " ", n);
			vendortab[e] = n;
		}
}

{
	ether = $1;
	ip    = $2;
	name  = $4;

	if (do_date)
		zeit = strftime("%Y-%m-%d %H:%M:%S  ", $3);

	if (!name)
		name = "<unknown>";

	if (do_vend) {
		vendorcode = tolower(ether);
		sub(/:[^:]+:[^:]+:[^:]+$/, "", vendorcode)
		if (!(vendor = vendortab[vendorcode]))
			vendor = "<unknown>";
	}

	s = sprintf("%s%-15s %-15s %-18s%s", zeit, ip, name, ether, vendor);
	print substr(s, 1, columns - 1);
}
'

#--