#!/usr/bin/perl

## check_services version 0.27
## check services on different hosts 
## and mail info
##
## license change 2001
## Copyright (c) 1999 Jeremy C. Reed. All Rights Reserved.
## This program is free software; you may redistribute it and/or modify
## it as long as you retain this entire copyright and notice.
## This software is provided as is and the author is not liable
## for anything resulting from its use.
##
## updated: Nov. 10, 1999

## use the --verbose switch to see what's happening

# @mail_list = ('firstperson@yahoo.com', 'anotherperson@hotmail.com');
@mail_list = ('your address on another machine');

# ignore is a router to be pinged just to see if I can get out!
# if I can't get out, of course, the other stuff won't work.
# @ignore = ('this machine's router's or gateway's ip');

@ignore = ();

# %routers = ('ip.to.check', 'a machine name but not used except for reporting',
#             '192.168.1.13, 'bob's router',
#             '10.1.228.75', '75.bogus.GW1.SEA5.foo.bar');

%routers = ('192.168.1.12',	'some router',
	    '10.1.228.29',	'some other router');

%ts =   ();

%dns =  ('192.168.0.5',		'ns1.foo.bar',
	 '10.1.228.99', 	'another dns');

%http = ('192.168.99.100',	'web.foo.bar');

%mail = ('10.1.1.200',	'mail.foo.bar',
	 '10.5.5.5', 	'my secondary MX');

%news = ();

$lynx = '/usr/bin/lynx';
$telnet = '/usr/bin/telnet';
$sleep = '/bin/sleep';
$ping = '/bin/ping';
$nslookup = '/usr/bin/nslookup';
$sendmail = '/usr/sbin/sendmail -t';

## main

if ($ARGV[0] eq '--verbose') { $verbose = '1'; }

if (! &check_ignore) {
  $all_problems = '';

  $all_problems .= &check_routers;
  $all_problems .= &check_terminal_servers;
  $all_problems .= &check_dns;
  $all_problems .= &check_http;
  $all_problems .= &check_mail;
  $all_problems .= &check_news;

  if ($all_problems) { &mail_problem; }
}
exit;

sub check_ignore {

  foreach $ip (@ignore) {
    if ($verbose) { print "checking $ip\n"; }
    $result = `$ping -c 1 $ip 2>&1`;
    if ($result =~ /0 packets received/) {
      if ($verbose) { print "problem $ip\n"; }
      return 1;
    }
  }
  return 0;
}

sub check_routers {

  my $problem;
  foreach $ip (keys %routers) {
    if ($verbose) { print "ROUTER: $ip (@routers{$ip})\n"; }
    $result = `$ping -c 1 $ip 2>&1`;
    if ($result =~ /0 packets received/) {
      $problem .= "ROUTER: $ip (@routers{$ip}) appears to have a problem.\n";
      if ($verbose) { print "problem $ip\n"; }
    }
  }
  return $problem;
}

sub check_terminal_servers {
  my $problem;
  foreach $ip (keys %ts) {
    if ($verbose) { print "TS: $ip (@ts{$ip})\n"; }
    $result = `$ping -c 1 $ip 2>&1`;
    if ($result =~ /0 packets received/) {
      $problem .= "TERMINAL SERVER: $ip (@ts{$ip}) appears to have a problem.\n";
      if ($verbose) { print "problem $ip\n"; }
    }
  }
  return $problem;
}

sub check_dns {
  my $problem;
  foreach $ip (keys %dns) {
    if ($verbose) { print "DNS: $ip (@dns{$ip})\n"; }
    $result = `$nslookup $ip $ip 2>&1`;
    if ($result =~ /Can\'t find server name/) {
      $problem .= "DNS: $ip (@dns{$ip}) timed out (can\'t find server name).\n";
    }
    elsif ($result =~ /can\'t find $ip: Non-existent host/) {
      $problem .= "DNS: $ip (@dns{$ip}) appears to have a problem.\n";
      if ($verbose) { print "problem $ip\n"; }
    }
  }
  return $problem;
}

sub check_http {
  my $problem;
  foreach $ip (keys %http) {
    if ($verbose) { print "HTTP: $ip (@http{$ip})\n"; }
    $results = `$lynx '$ip' -source -term=vt100 2>&1`;
    if (($results =~ /404 Not Found/) ||
      ($results =~ /Can\'t access startfile/)) {
      $problem .= "HTTP: $ip (@http{$ip}) appears to have a problem.\n";
      if ($verbose) { print "problem $ip\n"; }
    }
  } 
  return $problem;
}

sub check_mail {
  my $problem;
  foreach $ip (keys %mail) {
    if ($verbose) { print "MAIL: $ip (@mail{$ip})\n"; }
    $results =
          `(echo quit ; $sleep 3) | $telnet $ip 25 2>&1`;
    if (($results =~ /Connection refused/) ||
        ($results =~ /Unknown host/) ||
        ($results =~ /Unable to connect/) ||
        ($results =~ /Connection timed out/)) {
      $problem .= "MAIL: $ip (@mail{$ip}) appears to have a problem.\n";
      if ($verbose) { print "problem $ip\n"; }
    }
  }
  return $problem;
}


sub check_news {
  my $problem, $bad;
  foreach $ip (keys %news) {
    if ($verbose) { print "NEWS: $ip (@news{$ip})\n"; }
    $bad = '';
    $results =
          `(echo quit ; $sleep 3) | $telnet $ip 119 2>&1`;

    if (($results =~ /Connection refused/) ||
        ($results =~ /Unknown host/) ||
        ($results =~ /Unable to connect/) ||
        ($results =~ /Connection timed out/)) {
      $bad = 1;
    }
    elsif ($results !~ /205 GoodBye/) {
      $bad = 1;
    }
    if ($bad) {
      $problem .= "NEWS: $ip (@news{$ip}) appears to have a problem.\n";
      if ($verbose) { print "problem $ip\n"; }
    }
  }
  return $problem;
}

sub mail_problem {

  foreach $email_address (@mail_list) {

    if ($verbose) { print "mailing to $email_address\n"; }

    open (SENDMAIL, "| $sendmail");
    print SENDMAIL <<end_of_header;
To: $email_address
Subject: Network/Server Problem Report

end_of_header
    print SENDMAIL "$all_problems";
    close (SENDMAIL);
  }
}