1#! @PATH_PERL@ -w
2
3# John Hay -- John.Hay@icomtek.csir.co.za / jhay@FreeBSD.org
4
5use Socket;
6use Getopt::Std;
7use vars qw($opt_n $opt_m);
8
9$ntpq = "ntpq";
10
11getopts('nm:');
12
13$dodns = 1;
14$dodns = 0 if (defined($opt_n));
15
16$max_hosts = (defined($opt_m) ? $opt_m :  99);
17$max_hosts = 0 if ( $max_hosts !~ /^\d+$/ );
18$nb_host = 1;
19
20$host = shift;
21$host ||= "127.0.0.1";
22
23for (;;) {
24	$nb_host++;
25	$rootdelay = 0;
26	$rootdispersion = 0;
27	$stratum = 255;
28	$cmd = "$ntpq -n -c rv $host";
29	open(PH, $cmd . "|") || die "failed to start command $cmd: $!";
30	while (<PH>) {
31		$stratum = $1 if (/stratum=(\d+)/);
32		$peer = $1 if (/peer=(\d+)/);
33		# Very old servers report phase and not offset.
34		$offset = $1 if (/(?:offset|phase)=([^\s,]+)/);
35		$rootdelay = $1 if (/rootdelay=([^\s,]+)/);
36		$rootdispersion = $1 if (/rootdispersion=([^\s,]+)/);
37		$refid = $1 if (/refid=([^\s,]+)/);
38	}
39	close(PH) || die "$cmd failed";
40	last if ($stratum == 255);
41	$offset /= 1000;
42	$syncdistance = ($rootdispersion + ($rootdelay / 2)) / 1000;
43	$dhost = $host;
44	# Only do lookups of IPv4 addresses. The standard lookup functions
45	# of perl only do IPv4 and I don't know if we should require extras.
46	if ($dodns && $host =~ /^(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})$/) {
47		$iaddr = inet_aton($host);
48		$name = (gethostbyaddr($iaddr, AF_INET))[0];
49		$dhost = $name if (defined($name));
50	}
51	printf("%s: stratum %d, offset %f, synch distance %f",
52	    $dhost, $stratum, $offset, $syncdistance);
53	printf(", refid '%s'", $refid) if ($stratum == 1);
54	printf("\n");
55	last if ($stratum == 0 || $stratum == 1 || $stratum == 16);
56	last if ($refid =~ /^127\.127\.\d{1,3}\.\d{1,3}$/);
57	last if ($nb_host > $max_hosts);
58
59	$cmd = "$ntpq -n -c \"pstat $peer\" $host";
60	open(PH, $cmd . "|") || die "failed to start command $cmd: $!";
61	$thost = "";
62	while (<PH>) {
63		$thost = $1, last if (/srcadr=(\S+),/);
64	}
65	close(PH) || die "$cmd failed";
66	last if ($thost eq "");
67	last if ($thost =~ /^127\.127\.\d{1,3}\.\d{1,3}$/);
68	$host = $thost;
69}
70
71