[master]

Checkin for 20680, adding perl script to look at lease files

1 files changed, 199 insertions, 0 deletions

diff --git a/contrib/dhcp-lease-list.pl b/contrib/dhcp-lease-list.pl
new file mode 100644
index 00000000..f7e8c0c3
--- /dev/null
+++ b/contrib/dhcp-lease-list.pl
@@ -0,0 +1,199 @@
+#!/usr/bin/perl
+#
+# Shows current leases.
+#
+# THIS SCRIPT IS PUBLIC DOMAIN, NO RIGHTS RESERVED!
+#
+# I've removed the email addresses of Christian and vom to avoid
+# putting them on spam lists.  If either of you would like to have
+# your email in here please send mail to the DHCP bugs list at ISC.
+#
+# 2008-07-13, Christian Hammers
+#
+# 2009-06-?? - added loading progress counter, pulls hostname, adjusted formatting
+#        vom
+#
+# 2013-04-22 - added option to choose lease file, made manufacture information
+#              optional, sar
+use strict;
+use warnings;
+use POSIX qw(strftime);
+
+my $LEASES = '/var/db/dhcpd.leases';
+my @all_leases;
+my @leases;
+
+my @OUIS = ('/usr/share/misc/oui.txt', '/usr/local/etc/oui.txt');
+my $OUI_URL = 'http://standards.ieee.org/regauth/oui/oui.txt';
+my $oui;
+
+my %data;
+
+my $opt_format = 'human';
+my $opt_keep = 'active';
+
+our $total_leases = 0;
+
+## Return manufactorer name for specified MAC address (aa:bb:cc:dd:ee:ff).
+sub get_manufactorer_for_mac($) {
+    my $manu = "-NA-";
+
+    if (defined $oui) {
+	$manu = join('-', ($_[0] =~ /^(..):(..):(..):/));
+	$manu = `grep -i '$manu' $oui | cut -f3`;
+	chomp($manu);
+    }
+
+    return $manu;
+}
+
+## Read oui.txt or print warning.
+sub check_oui_file() {
+
+    for my $oui_cand (@OUIS) {
+        if ( -r $oui_cand) {
+        $oui = $oui_cand;
+        last;
+        }
+    }
+
+    if (not defined $oui) {
+	print(STDERR "To get manufacturer names please download $OUI_URL ");
+	print(STDERR "to /usr/local/etc/oui.txt\n");
+    }
+}
+
+## Read current leases file into array.
+sub read_dhcpd_leases() {
+
+    open(F, $LEASES) or die("Cannot open $LEASES: $!");
+    my $content = join('', <F>);
+    close(F);
+    @all_leases = split(/lease/, $content);
+
+    foreach my $lease (@all_leases) {
+    if ($lease =~ /^\s+([\.\d]+)\s+{.*starts \d+ ([\/\d\ \:]+);.*ends \d+ ([\/\d\ \:]+);.*ethernet ([a-f0-9:]+);/s) {
+       ++$total_leases;
+       }
+    }
+}
+
+## Add manufactor name and sort out obsolet assignements.
+sub process_leases() {
+    my $gm_now = strftime("%Y/%m/%d %H:%M:%S", gmtime());
+    my %tmp_leases; # for sorting and filtering
+
+    my $counter = 1;
+
+    # parse entries
+    foreach my $lease (@all_leases) {
+	# skip invalid lines
+	next if not ($lease =~ /^\s+([\.\d]+)\s+{.*starts \d+ ([\/\d\ \:]+);.*ends \d+ ([\/\d\ \:]+);.*ethernet ([a-f0-9:]+);(.*client-hostname \"(\S+)\";)*/s);
+	# skip outdated lines
+	next if ($opt_keep eq 'active'  and  $3 lt $gm_now);
+
+	my $percent = (($counter / $total_leases)*100);
+	printf "Processing: %2d%% complete\r", $percent;
+	++$counter;
+
+	 my $hostname = "-NA-";
+	 if ($6) {
+	     $hostname = $6;
+	 }
+
+	my $mac = $4;
+	my $date_end = $3;
+	my %entry = (
+	    'ip' => $1,
+	    'date_begin' => $2,
+	    'date_end' => $date_end,
+	    'mac' => $mac,
+	    'hostname' => $hostname,
+	    'manu' => get_manufactorer_for_mac($mac),
+	    );
+
+	$entry{'date_begin'} =~ s#\/#-#g; # long live ISO 8601
+	$entry{'date_end'}   =~ s#\/#-#g;
+
+	if ($opt_keep eq 'all') {
+	    push(@leases, \%entry);
+	} elsif (not defined $tmp_leases{$mac}  or  $tmp_leases{$mac}{'date_end'} gt $date_end) {
+	    $tmp_leases{$mac} = \%entry;
+	}
+    }
+
+    # In case we used the hash to filtered
+    if (%tmp_leases) {
+	foreach (sort keys %tmp_leases) {
+	    my $h = $tmp_leases{$_};
+	    push(@leases, $h);
+	}
+    }
+
+    # print "\n";
+
+}
+
+# Output all valid leases.
+sub output_leases() {
+    if ($opt_format eq 'human') {
+	printf "%-19s%-16s%-15s%-20s%-20s\n","MAC","IP","hostname","valid until","manufacturer";
+	print("===============================================================================================\n");
+    }
+    foreach (@leases) {
+       if ($opt_format eq 'human') {
+	   printf("%-19s%-16s%-15s%-20s%-20s\n",
+		  $_->{'mac'},       # MAC
+		  $_->{'ip'},        # IP address
+		  $_->{'hostname'},  # hostname
+		  $_->{'date_end'},  # Date
+		  $_->{'manu'});     # manufactor name
+       } else {
+	   printf("MAC %s IP %s HOSTNAME %s BEGIN %s END %s MANUFACTURER %s\n",
+		  $_->{'mac'},
+		  $_->{'ip'},
+		  $_->{'hostname'},
+		  $_->{'date_begin'},
+		  $_->{'date_end'},
+		  $_->{'manu'});
+       }
+    }
+}
+
+# Commandline Processing.
+sub cli_processing() {
+    while (my $arg = shift(@ARGV)) {
+	if ($arg eq '--help') {
+	    print(
+		"Prints active DHCP leases.\n\n".
+		"Usage: $0 [options]\n".
+		" --help      shows this help\n".
+		" --parsable  machine readable output with full dates\n".
+		" --last      prints the last (even if end<now) entry for every MAC\n".
+		" --all       prints all entries i.e. more than one per MAC\n".
+		" --lease     uses the next argument as the name of the lease file\n".
+		"             the default is /var/db/dhcpd.leases\n".
+		"\n");
+	    exit(0);
+	} elsif ($arg eq '--parsable') {
+	    $opt_format = 'parsable';
+	} elsif ($arg eq '--last') {
+	    $opt_keep = 'last';
+	} elsif ($arg eq '--all') {
+	    $opt_keep = 'all';
+	} elsif ($arg eq '--lease') {
+	    $LEASES = shift(@ARGV);
+	} else {
+	    die("Unknown option $arg");
+	}
+    }
+}
+
+#
+# main()
+#
+cli_processing();
+check_oui_file();
+read_dhcpd_leases();
+process_leases();
+output_leases();