# isPatchInstalled.pl checks if specified MS hotfix (patch) is installed on
# specified machine(s).  Initial implementation checks hotfixes subkeys in
# registry.
#
# Written 17-sep-03 by fgb (another quick-n-dirty script)
# Mod 25-may-2005, fgb: added key4 (windows xp)
# Mod 17-aug-2005, fgb: broke out ChkSubkey function from ChkReg, added win 2003 support.

require "ctime.pl";
use Net::Ping;
use Win32::Registry;

### evil globals: ###

$bDebug = 0;
$sAppName = "isPatchInstalled";
$sDate = &ctime(time); chop $sDate;
$bFound = 0;
$hkr;
$bListAll = 0;
$sLocalMachine = Win32::NodeName;
$sMachine = "";
$sMachineList = "";
$sPatch = "";
$sServer = "";
$bSingleMachine = 0;
$nTotalMachines = 0;
$bVerbose = 1;
$sVersion = "1.1";

_main:

ParseCmdArgs();

print "$sAppName $sVersion startup at $sDate...\n\n";

if ($sMachineList eq "") { 
  if (! $bSingleMachine) { $sMachine = $sLocalMachine; }
  if (-1 != &DoCheck()) { ++$nTotalMachines; }
  }
else { 
  open(FPCLIST,$sMachineList) || die "Can't open file $sMachineList: $!\n";

  while (<FPCLIST>) {
    if (!/^\!/) {						# skip comments
      chop $_;
      s/\s(.*)//;						# remove whitespace
      s/^\\\\//;						# remove leading '\\'
      $sMachine = $_;
      if (&IsVisibleOnNet()) {
        if (-1 != &DoCheck()) { ++$nTotalMachines; }
        }
      }
    }
  close(FPCLIST);
  }

_thatsAllFolks:

if ($nTotalMachines == 1) { 
  print "\n$sPatch ";  
  if (!$bFound) { print "not "; }
  print "installed on $sMachine.\n";
  }
else { print "\n$sAppName: checked $nTotalMachines machines.\n"; }

print "\n$sAppName complete.\n";

### end of execution

### subroutines here ###

sub DoCheck {
  $sServer = "\\\\" . $sMachine;				# used by Connect()
  print "Checking $sMachine...\n";
  if ($bListAll) { print "Listing all installed patches:\n"; }

  if (&ChkReg()) {
    $nFixCount++; 
    }
  
  return 0;
}

sub ChkReg {
  my $sKey1 = "SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\Hotfix";
  my $sKeyRoot = "SOFTWARE\\Microsoft\\Updates\\";
  my $sKey = "";
  my @locations = 'DataAccess','Windows 2000','Windows XP','Windows Server 2003';
  my $nRet = 1;

  if (!$HKEY_LOCAL_MACHINE->Connect($sServer,$hkr)) { 
    print "can't connect to $sServer: $!"; 
    return 0;
    }
  &ChkSubkey($sKey1);
  if ($bFound) { goto _skipIt; }

  foreach (@locations) {
    $sKey = $sKeyRoot . $_;
    &ChkSubkey($sKey);
    if ($bFound) { last; }
    }

_skipIt:
  $hkr->Close();

  return $nRet;
}

sub ChkSubkey {
  my $hk;
  my $skey = $_[0];
  my $nRetVal = 1;
  my @subkeys = ();
  my $pSubkeys = \@subkeys;			# reference (ptr) to subkeys list

  $#subkeys = 0;				# truncate any elements from prior calls

  if (!$hkr->Open($skey,$hk)) { print "FYI: can't open key $skey\n"; goto _endChkSubkey; }
  if (!$hk->GetKeys($pSubkeys))
    { print "error reading subkeys of $skey\n"; $nRetVal = 0; }
  $hk->Close();

  my $nCount = scalar @subkeys;

  if (0 == $nCount) {				# no subkeys 
    if ($bVerbose) { print "no subkeys under $skey\n"; }
    }
  else {					# iterate thru each subkey:
    foreach (@subkeys) {
      if ($bListAll) { print "$_\n"; next; }
      else { if (/$sPatch/) { print "$_ installed\n"; $bFound = 1; last; }
        }
      }
    }
_endChkSubkey:

return $nRetVal;
  }

sub Help {
  printf("%s version %s by fgb\n",$sAppName,$sVersion);
  print "Check machines for installed hotfix.\n";
  print "\nusage: $sAppName patch [\\\\machine || /list=machines.lis] \n";
  print "\nwarning: only performs regex match so a short patch could be a substring of an\n";
  print "installed patch with a longer number! (enter the whole number)\n";
}

sub IsVisibleOnNet {
  $p = Net::Ping->new("icmp");
  return ($p->ping($sMachine,1));
}

sub ParseCmdArgs {
  if ($bDebug) { $na = $#ARGV+1; print "dbg: entered ParseCmdArgs w $na args...\n";}
  while ($#ARGV+1) {
    $_ = shift @ARGV;
    if ($bDebug) {
      print "dbg: parsing $_\n";
      }
    if (/^[\/\-]/) {				# is arg a switch?
      $arg = lc(substr($_,1,3));		# parse 1st 3 chars:

      if ($arg eq "deb") { $bDebug = 1; }
      if ($arg eq "lis") {
        $i = index($_,"=");
        $i++;
        $sMachineList = sprintf("%s",substr($_,$i));
        }
      if (($arg eq "hel") || (substr($arg,0,1) eq "?")) {
        &Help();
	exit;
        }
      }
    else {					# not a switch
      if (/^[\\]/) {				# single machine (UNC)
        s/\s(.*)//;				# remove whitespace
        s/^\\\\//;				# remove leading \\
        $sMachine = $_;
        $bSingleMachine = 1;
        }
      else { $sPatch = $_; }
      }
    }
  if ($sPatch eq "") { $bListAll = 1; }
  if ($bDebug) {
    $bVerbose = 1;
    print "dbg: patch=$sPatch sMachine=$sMachine sMachineList=$sMachineList\n";
    }
  }

__END__