1#! /usr/local/bin/perl -w
2#
3
4# John Hay -- John.Hay@icomtek.csir.co.za / jhay@FreeBSD.org
5
6use Socket;
7use Getopt::Std;
8use vars qw($opt_n);
9
10$ntpq = "ntpq";
11
12getopts('n');
13
14$dodns = 1;
15$dodns = 0 if (defined($opt_n));
16
17$host = shift;
18$host ||= "127.0.0.1";
19
20for (;;) {
21	$stratum = 255;
22	$cmd = "$ntpq -n -c rv $host";
23	open(PH, $cmd . "|") || die "failed to start command $cmd: $!";
24	while (<PH>) {
25		$stratum = $1 if (/stratum=(\d+)/);
26		$peer = $1 if (/peer=(\d+)/);
27		# Very old servers report phase and not offset.
28		$offset = $1 if (/(?:offset|phase)=([^\s,]+)/);
29		$rootdelay = $1 if (/rootdelay=([^\s,]+)/);
30		$refid = $1 if (/refid=([^\s,]+)/);
31	}
32	close(PH) || die "$cmd failed";
33	last if ($stratum == 255);
34	$offset /= 1000;
35	$rootdelay /= 1000;
36	$dhost = $host;
37	# Only do lookups of IPv4 addresses. The standard lookup functions
38	# of perl only do IPv4 and I don't know if we should require extras.
39	if ($dodns && $host =~ /^(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})$/) {
40		$iaddr = inet_aton($host);
41		$name = (gethostbyaddr($iaddr, AF_INET))[0];
42		$dhost = $name if (defined($name));
43	}
44	printf("%s: stratum %d, offset %f, root distance %f",
45	    $dhost, $stratum, $offset, $rootdelay);
46	printf(", refid '%s'", $refid) if ($stratum == 1);
47	printf("\n");
48	last if ($stratum == 0 || $stratum == 1 || $stratum == 16);
49	last if ($refid =~ /^127\.127\.\d{1,3}\.\d{1,3}$/);
50
51	$cmd = "$ntpq -n -c \"pstat $peer\" $host";
52	open(PH, $cmd . "|") || die "failed to start command $cmd: $!";
53	$thost = "";
54	while (<PH>) {
55		$thost = $1, last if (/srcadr=(\S+),/);
56	}
57	close(PH) || die "$cmd failed";
58	last if ($thost eq "");
59	$host = $thost;
60}
61
62