#!/usr/bin/perl -w
# --*-perl-*-
;#
;# ntploopstat,v 3.1 1993/07/06 01:09:11 jbj Exp
;#
;# Poll NTP server using NTP mode 7 loopinfo request.
;# Log info and timestamp to file for processing by ntploopwatch.
;#
;#
;# Copyright (c) 1992
;# Rainer Pruy Friedrich-Alexander Universitaet Erlangen-Nuernberg
;#
;#################################################################
;#
;# The format written to the logfile is the same as used by xntpd
;# for the loopstats file.
;# This script however allows to gather loop filter statistics from
;# remote servers where you do not have access to the loopstats logfile.
;#
;# Please note: Communication delays affect the accuracy of the
;# timestamps recorded. Effects from these delays will probably
;# not show up, as timestamps are recorded to the second only.
;# (Should have implemented &gettimeofday()..)
;#
$0 =~ s!^.*/([^/]+)$!$1!; # beautify script name
$ntpserver = 'localhost'; # default host to poll
$delay = 60; # default sampling rate
;# keep it shorter than minpoll (=64)
;# to get all values
require "ctime.pl";
;# handle bug in early ctime distributions
$ENV{'TZ'} = 'MET' unless defined($ENV{'TZ'}) || $] > 4.010;
if (defined(@ctime'MoY))
{
*MonthName = *ctime'MoY;
}
else
{
@MonthName = ('Jan','Feb','Mar','Apr','May','Jun',
'Jul','Aug','Sep','Oct','Nov','Dec');
}
;# this routine can be redefined to point to syslog if necessary
sub msg
{
return unless $verbose;
print STDERR "$0: ";
printf STDERR @_;
}
;#############################################################
;#
;# process command line
$usage = <<"E-O-S";
usage:
$0 [-d<delay>] [-t<timeout>] [-l <logfile>] [-v] [ntpserver]
E-O-S
while($_ = shift)
{
/^-v(\d*)$/ && ($verbose=($1 eq '') ? 1 : $1,1) && next;
/^-d(\d*)$/ &&
do {
($1 ne '') && ($delay = $1,1) && next;
@ARGV || die("$0: delay value missing after -d\n$usage");
$delay = shift;
($delay >= 0) || die("$0: bad delay value \"$delay\"\n$usage");
next;
};
/^-l$/ &&
do {
@ARGV || die("$0: logfile missing after -l\n$usage");
$logfile = shift;
next;
};
/^-t(\d*(\.\d*)?)$/ &&
do {
($1 ne '') && ($timeout = $1,1) && next;
@ARGV || die("$0: timeout value missing after -t\n$usage\n");
$timeout = shift;
($timeout > 0) ||
die("$0: bad timeout value \"$timeout\"\n$usage");
next;
};
/^-/ && die("$0: unknown option \"$_\"\n$usage");
;# any other argument is server to poll
$ntpserver = $_;
last;
}
if (@ARGV)
{
warn("unexpected arguments: ".join(" ",@ARGV).".\n");
die("$0: too many servers specified\n$usage");
}
;# logfile defaults to include server name
;# The name of the current month is appended and
;# the file is opened and closed for each sample.
;#
$logfile = "loopstats:$ntpserver." unless defined($logfile);
$timeout = 12.0 unless defined($timeout); # wait $timeout seconds for reply
$MAX_FAIL = 60; # give up after $MAX_FAIL failed polls
$MJD_1970 = 40587;
if (eval 'require "syscall.ph";')
{
if (defined(&SYS_gettimeofday))
{
;# assume standard
;# gettimeofday(struct timeval *tp,struct timezone *tzp)
;# syntax for gettimeofday syscall
;# tzp = NULL -> undef
;# tp = (long,long)
eval 'sub time { local($tz) = pack("LL",0,0);
(&msg("gettimeofday failed: $!\n"),
return (time))
unless syscall(&SYS_gettimeofday,$tz,undef) == 0;
local($s,$us) = unpack("LL",$tz);
return $s + $us/1000000; }';
local($t1,$t2,$t3);
$t1 = time;
eval '$t2 = &time;';
$t3 = time;
die("$0: gettimeofday failed: $@.\n") if defined($@) && $@;
die("$0: gettimeofday inconsistency time=$t1,gettimeofday=$t2,time=$t2\n")
if (int($t1) != int($t2) && int($t3) != int($t2));
&msg("Using gettimeofday for timestamps\n");
}
else
{
warn("No gettimeofday syscall found - using time builtin for timestamps\n");
eval 'sub time { return time; }';
}
}
else
{
warn("No syscall.ph file found - using time builtin for timestamps\n");
eval 'sub time { return time; }';
}
;#------------------+
;# from ntp_request.h
;#------------------+
;# NTP mode 7 packet format:
;# Byte 1: ResponseBit MoreBit Version(3bit) Mode(3bit)==7
;# Byte 2: AuthBit Sequence # - 0 - 127 see MoreBit
;# Byte 3: Implementation #
;# Byte 4: Request Code
;#
;# Short 1: Err(3bit) NumItems(12bit)
;# Short 2: MBZ(3bit)=0 DataItemSize(12bit)
;# 0 - 500 byte Data
;# if AuthBit is set:
;# Long: KeyId
;# 2xLong: AuthCode
;#
$IMPL_XNTPD = 2;
$REQ_LOOP_INFO = 8;
;# request packet for REQ_LOOP_INFO:
;# B1: RB=0 MB=0 V=2 M=7
;# B2: S# = 0
;# B3: I# = IMPL_XNTPD
;# B4: RC = REQ_LOOP_INFO
;# S1: E=0 NI=0
;# S2: MBZ=0 DIS=0
;# data: 32 byte 0 padding
;# 8byte timestamp if encryption, 0 padding otherwise
$loopinfo_reqpkt =
pack("CCCC nn x32 x8", 0x17, 0, $IMPL_XNTPD, $REQ_LOOP_INFO, 0, 0);
;# ignore any auth data in packets
$loopinfo_response_size =
1+1+1+1+2+2 # header size like request pkt
+ 8 # l_fp last_offset
+ 8 # l_fp drift_comp
+ 4 # u_long compliance
+ 4 # u_long watchdog_timer
;
$loopinfo_response_fmt = "C4n2N2N2NN";
$loopinfo_response_fmt_v2 = "C4n2N2N2N2N";
;#
;# prepare connection to server
;#
;# workaround for broken socket.ph on dynix_ptx
eval 'sub INTEL {1;}' unless defined(&INTEL);
eval 'sub ATT {1;}' unless defined(&ATT);
require "sys/socket.ph";
require 'netinet/in.ph';
;# if you do not have netinet/in.ph enable the following lines
;#eval 'sub INADDR_ANY { 0x00000000; }' unless defined(&INADDR_ANY);
;#eval 'sub IPPRORO_UDP { 17; }' unless defined(&IPPROTO_UDP);
if ($ntpserver =~ /^((0x?)?\w+)\.((0x?)?\w+)\.((0x?)?\w+)\.((0x?)?\w+)$/)
{
local($a,$b,$c,$d) = ($1,$3,$5,$7);
$a = oct($a) if defined($2);
$b = oct($b) if defined($4);
$c = oct($c) if defined($6);
$d = oct($d) if defined($8);
$server_addr = pack("C4", $a,$b,$c,$d);
$server_mainname
= (gethostbyaddr($server_addr,&AF_INET))[$[] || $ntpserver;
}
else
{
($server_mainname,$server_addr)
= (gethostbyname($ntpserver))[$[,$[+4];
die("$0: host \"$ntpserver\" is unknown\n")
unless defined($server_addr);
}
&msg ("Address of server \"$ntpserver\" is \"%d.%d.%d.%d\"\n",
unpack("C4",$server_addr));
$proto_udp = (getprotobyname('udp'))[$[+2] || &IPPROTO_UDP;
$ntp_port =
(getservbyname('ntp','udp'))[$[+2] ||
(warn "Could not get port number for service \"ntp/udp\" using 123\n"),
($ntp_port=123);
;#
0 && &SOCK_DGRAM; # satisfy perl -w ...
socket(S, &AF_INET, &SOCK_DGRAM, $proto_udp) ||
die("Cannot open socket: $!\n");
bind(S, pack("S n N x8", &AF_INET, 0, &INADDR_ANY)) ||
die("Cannot bind: $!\n");
($my_port, $my_addr) = (unpack("S n a4 x8",getsockname(S)))[$[+1,$[+2];
&msg("Listening at address %d.%d.%d.%d port %d\n",
unpack("C4",$my_addr), $my_port);
$server_inaddr = pack("Sna4x8", &AF_INET, $ntp_port, $server_addr);
;############################################################
;#
;# the main loop:
;# send request
;# get reply
;# wait til next sample time
undef($lasttime);
$lostpacket = 0;
while(1)
{
$stime = &time;
&msg("Sending request $stime...\n");
$ret = send(S,$loopinfo_reqpkt,0,$server_inaddr);
if (! defined($ret) || $ret < length($loopinfo_reqpkt))
{
warn("$0: send failed ret=($ret): $!\n");
$fail++;
next;
}
&msg("Waiting for reply...\n");
$mask = ""; vec($mask,fileno(S),1) = 1;
$ret = select($mask,undef,undef,$timeout);
if (! defined($ret))
{
warn("$0: select failed: $!\n");
$fail++;
next;
}
elsif ($ret == 0)
{
warn("$0: request to $ntpserver timed out ($timeout seconds)\n");
;# do not count this event as failure
;# it usually this happens due to dropped udp packets on noisy and
;# havily loaded lines, so just try again;
$lostpacket = 1;
next;
}
&msg("Receiving reply...\n");
$len = 520; # max size of a mode 7 packet
$reply = ""; # just make it defined for -w
$ret = recv(S,$reply,$len,0);
if (!defined($ret))
{
warn("$0: recv failed: $!\n");
$fail++;
next;
}
$etime = &time;
&msg("Received at\t$etime\n");
;#$time = ($stime + $etime) / 2; # symmetric delay assumed
$time = $etime; # the above assumption breaks for X25
;# so taking etime makes timestamps be a
;# little late, but keeps them increasing
;# monotonously
&msg(sprintf("Reply from %d.%d.%d.%d took %f seconds\n",
(unpack("SnC4",$ret))[$[+2 .. $[+5], ($etime - $stime)));
if ($len < $loopinfo_response_size)
{
warn("$0: short packet ($len bytes) received ($loopinfo_response_size bytes expected\n");
$fail++;
next;
}
($b1,$b2,$b3,$b4,$s1,$s2,
$offset_i,$offset_f,$drift_i,$drift_f,$compl,$watchdog)
= unpack($loopinfo_response_fmt,$reply);
;# check reply
if (($s1 >> 12) != 0) # error !
{
die("$0: got error reply ".($s1>>12)."\n");
}
if (($b1 != 0x97 && $b1 != 0x9f) || # Reply NotMore V=2 M=7
($b2 != 0 && $b2 != 0x80) || # S=0 Auth no/yes
$b3 != $IMPL_XNTPD || # ! IMPL_XNTPD
$b4 != $REQ_LOOP_INFO || # Ehh.. not loopinfo reply ?
$s1 != 1 || # ????
($s2 != 24 && $s2 != 28) #
)
{
warn("$0: Bad/unexpected reply from server:\n");
warn(" \"".unpack("H*",$reply)."\"\n");
warn(" ".sprintf("b1=%x b2=%x b3=%x b4=%x s1=%d s2=%d\n",
$b1,$b2,$b3,$b4,$s1,$s2));
$fail++;
next;
}
elsif ($s2 == 28)
{
;# seems to be a version 2 xntpd
($b1,$b2,$b3,$b4,$s1,$s2,
$offset_i,$offset_f,$drift_i,$drift_f,$compl_i,$compl_f,$watchdog)
= unpack($loopinfo_response_fmt_v2,$reply);
$compl = &lfptoa($compl_i, $compl_f);
}
$time -= $watchdog;
$offset = &lfptoa($offset_i, $offset_f);
$drift = &lfptoa($drift_i, $drift_f);
&log($time,$offset,$drift,$compl) && ($fail = 0);;
}
continue
{
die("$0: Too many failures - terminating\n") if $fail > $MAX_FAIL;
&msg("Sleeping " . ($lostpacket ? ($delay / 2) : $delay) . " seconds...\n");
sleep($lostpacket ? ($delay / 2) : $delay);
$lostpacket = 0;
}
sub log
{
local($time,$offs,$freq,$cmpl) = @_;
local($y,$m,$d);
local($fname,$suff) = ($logfile);
;# silently drop sample if distance to last sample is too low
if (defined($lasttime) && ($lasttime + 2) >= $time)
{
&msg("Dropped packet - old sample\n");
return 1;
}
;# $suff determines which samples end up in the same file
;# could have used $year (;-) or WeekOfYear, DayOfYear,....
;# Change it to your suit...
($d,$m,$y) = (localtime($time))[$[+3 .. $[+5];
$suff = sprintf("%04d%02d%02d",$y+1900,$m+1,$d);
$fname .= $suff;
if (!open(LOG,">>$fname"))
{
warn("$0: open($fname) failed: $!\n");
$fail++;
return 0;
}
else
{
;# file format
;# MJD seconds offset drift compliance
printf LOG ("%d %.3lf %.8lf %.7lf %d\n",
int($time/86400)+$MJD_1970,
$time - int($time/86400) * 86400,
$offs,$freq,$cmpl);
close(LOG);
$lasttime = $time;
}
return 1;
}
;# see ntp_fp.h to understand this
sub lfptoa
{
local($i,$f) = @_;
local($sign) = 1;
if ($i & 0x80000000)
{
if ($f == 0)
{
$i = -$i;
}
else
{
$f = -$f;
$i = ~$i;
$i += 1; # 2s complement
}
$sign = -1;
;#print "NEG: $i $f\n";
}
else
{
;#print "POS: $i $f\n";
}
;# unlike xntpd I have perl do the dirty work.
;# Using floats here may affect precision, but
;# currently these bits aren't significant anyway
return $sign * ($i + $f/2**32);
}