contrib/check_ica_master_browser.pl

   1 #!/usr/bin/perl -w
   2
   3 # $Id: check_ica_master_browser.pl 1099 2005-01-25 09:09:33Z stanleyhopcroft $
   4
   5 # Revision 1.1  2005/01/25 09:09:33  stanleyhopcroft
   6 # New plugin - checks that ICA master browser is what it should be (important for firewalled dialup)
   7 #
   8
   9 use strict ;
  10
  11 use IO::Socket;
  12 use IO::Select;
  13 use Getopt::Long ;
  14
  15 use lib qw(/usr/local/nagios/libexec) ;
  16 use utils qw(%ERRORS &print_revision &support &usage);
  17 use packet_utils qw(&pdump &tethereal) ;
  18
  19 my $PROGNAME = 'check_ica_master_browser' ;
  20
  21 # You might have to change this...
  22
  23 my $PACKET_TIMEOUT      = 1;
  24                                                                                                 # Number of seconds to wait for further UDP packets
  25 my $TEST_COUNT          = 2;
  26                                                                                                 # Number of datagrams sent without reply
  27 my $BUFFER_SIZE         = 1500;
  28                                                                                                 # buffer size used for 'recv' calls.
  29 my $ICA_PORT            = 1604;
  30                                                                                                 # what port ICA runs on. Unlikely to change.
  31
  32 # End user config.
  33
  34 my ($debug, $preferred_master, $bcast_addr, $ica_browser, $timeout) ;
  35
  36 Getopt::Long::Configure('bundling', 'no_ignore_case');
  37 GetOptions
  38         ("V|version"     => \&version,
  39          "h|help"        => \&help,
  40          "v|verbose"     => \$debug,
  41          "B|broadcast_addr:s"   => \$bcast_addr,
  42          "I|ica_browser:s"      => \$ica_browser,
  43          "P|preferred_master:s" => \$preferred_master,
  44          "T|Packet_timeout:i"   => \$timeout,
  45 ) ;
  46
  47
  48 my $broadcast_addr = $1 if $bcast_addr and $bcast_addr =~ m#(\d+\.\d+\.\d+\.\d+)# ;
  49 usage("Invalid broadcast address: $bcast_addr")
  50         if $bcast_addr and not defined($broadcast_addr)  ;
  51
  52 usage("You must provide either the name of an ICA browser or the broadcast address of the subnet containing them\n")
  53         unless ($ica_browser or $broadcast_addr) ;
  54
  55 usage("You must provide the name or address of a preferred ICA master browser\n")
  56         unless ($preferred_master) ;
  57
  58 my $preferred_master_n = $preferred_master =~ m#(\d+\.\d+\.\d+\.\d+)#
  59         ? $preferred_master
  60         : inet_ntoa(scalar gethostbyname($preferred_master)) ;
  61
  62 my $Timeout = $timeout || $PACKET_TIMEOUT ;
  63
  64                                                                                                 # Definitions of query strings. Change at your own risk :)
  65                                                                                                 # this info was gathered with tcpdump whilst trying to use an ICA client,
  66                                                                                                 # so I'm not 100% sure of what each value is.
  67
  68 my $bcast_helo = &tethereal(<<'End_of_Tethereal_trace', '1e') ;
  69 0020  ff ff 04 d6 06 44 00 26 4a 76 1e 00 01 30 02 fd   .....D.&Jv...0..
  70 0030  a8 e3 00 02 f5 95 9f f5 30 07 00 00 00 00 00 00   ........0.......
  71 0040  00 00 00 00 00 00 01 00                           ........
  72 End_of_Tethereal_trace
  73
  74 my $direct_helo = &tethereal(<<'End_of_Tethereal_trace', '20') ;
  75 0020  64 17 05 0f 06 44 00 28 ab b5 20 00 01 30 02 fd   d....D.(.. ..0..
  76 0030  a8 e3 00 00 00 00 00 00 00 00 00 00 00 00 00 00   ................
  77 0040  00 00 00 00 00 00 00 00 00 00                     ........
  78 End_of_Tethereal_trace
  79
  80 my $Udp =  IO::Socket::INET->new( Proto => 'udp' )
  81         || die "Socket failure: $!";
  82
  83                                                                                                 # select is here to allow us to set timeouts on the connections.  Otherwise they
  84                                                                                                 # just 'stop' until a server appears.
  85
  86 my $select =  IO::Select->new($Udp)
  87         || die "Select failure: $!";
  88
  89 $Udp->sockopt(SO_BROADCAST, 1 );
  90
  91 my ($remote_host, $buff, $destination, $raddr, $rport, $rhost, @remote_response);
  92 my ($query_message, $send_addr, $this_test) ;
  93
  94 $buff = '';
  95 $this_test = 0;
  96
  97                                                                                                 # If there is no response to the first helo packet it will be resent
  98                                                                                                 # up to $TEST_COUNT (see at the top).
  99
 100 $query_message = $broadcast_addr ? $bcast_helo : $direct_helo ;
 101 $destination   = $broadcast_addr ? $broadcast_addr: $ica_browser ;
 102 $send_addr = sockaddr_in($ICA_PORT, inet_aton($destination) ) ;
 103
 104 while ( ++$this_test <= $TEST_COUNT && !$buff ) {
 105
 106         print "Sending helo datagram. datagram number: ", $this_test, "\n"
 107                 if $debug ;
 108
 109         print "Querying $destination for master browser\n"
 110                 if  $debug  ;
 111         &pdump($query_message)
 112                 if $debug ;
 113         $Udp->send($query_message, 0, $send_addr );
 114         if ( $select->can_read($Timeout) ) {
 115                 $remote_host = $Udp->recv($buff, $BUFFER_SIZE, 0 );
 116         }
 117
 118         last
 119                 if $buff ;
 120         sleep 1 ;
 121
 122 }
 123
 124                                                                                                 # Ok we've looped several times, looking for a response. If we don't have one
 125                                                                                                 # yet, we simply mark the whole lot as being unavailable.
 126
 127 unless ( $buff ) {
 128         print "Failed. No response to helo datagram (master browser query) from $destination.\n" ;
 129         exit $ERRORS{CRITICAL} ;
 130 }
 131
 132 ($rport, $raddr) = sockaddr_in( $remote_host );
 133 $rhost = gethostbyaddr( $raddr, AF_INET );
 134 my @tmpbuf = unpack('C*', $buff );
 135 if ( $debug ) {
 136         print "$rhost:$rport responded with: ",length($buff), " bytes\n";
 137         &pdump($buff) ;
 138 }
 139
 140                                                                                                 # Now we have a response, then we need to figure out the master browser, and
 141                                                                                                 # query it for published applications...
 142
 143 my $master_browser = join '.', @tmpbuf[32..35] ;
 144 my ($master_browser_a) = gethostbyaddr(inet_aton($master_browser), AF_INET) =~ /^(\w+?)\./ ;
 145
 146                                                                                                 # Ok should probably error check this, because it's remotely possible
 147                                                                                                 # that a server response might be completely wrong...
 148
 149 print "Master browser = $master_browser_a/$master_browser\n"
 150         if  $debug ;
 151
 152 $send_addr = sockaddr_in($ICA_PORT, inet_aton($master_browser));
 153
 154 my $subject_clause = $bcast_addr ? "of the \"$destination\" subnet" : "known to ICA server \"$destination\"" ;
 155
 156 if ( $master_browser eq  $preferred_master_n ) {
 157         print "Preferred master browser \"$preferred_master\" __is__ the master browser (\"$master_browser_a/$master_browser\") $subject_clause.\n" ;
 158         exit $ERRORS{OK} ;
 159 } else {
 160         print "\"\u$preferred_master\" is __not__ the master browser (\"$master_browser_a/$master_browser\") $subject_clause: remote clients (dialup) may not find Published applications from Master Browser.\n" ;
 161         exit $ERRORS{CRITICAL} ;
 162 }
 163
 164 close $Udp;
 165
 166
 167 sub print_usage () {
 168         print "Usage: $PROGNAME (-B <broadcast_address>| -I <citrix_server>) - P <preferred_master_browser>" ;
 169 }
 170
 171 sub print_help () {
 172         print_revision($PROGNAME,'$Revision: 1099 $ ');
 173         print "Copyright (c) 2002 Ed Rolison/Tom De Blende/S Hopcroft
 174
 175 Perl Check Citrix Master Browser plugin for Nagios.
 176
 177 Returns OK if the Citrix master browser is that given by the -P option.
 178
 179 The plugin works by
 180   If the -B option is specified, sends a broadcast helo to find the address of the Citrix master browser in the specified subnet.
 181     return critical if there is no reply;
 182   Else if the -I option is specified
 183     send a direct helo to the specified server until there is a response (containing the address of the Citrix master browser)
 184
 185
 186   return Critical if the response does not contain the address of the 'preferred master browser' (-P option).
 187   return OK
 188
 189   How ICA Clients Use the Master ICA Browser.
 190
 191 Citrix ICA Clients must locate the master browser to get the address of a server or published application.
 192
 193 The Citrix ICA Client can locate the master browser by sending out broadcast packets, or,
 194 if the address of a Citrix server is specified in the Citrix ICA Client or in an ICA file,
 195 the ICA Client locates the master browser by sending directed packets to the specified address.
 196 The ICA Client requests the address of the ICA master browser from the Citrix server.
 197
 198 ";
 199         print_usage();
 200         print '
 201 -B, --broadcast_address:STRING
 202    The broadcast address that should contain Citrix master browser. This option takes precedence over -I.
 203 -I, --ica_browser:STRING
 204    Optional name or address of an ICA server that could be the master browser (used when broadcast not possible).
 205 -P, --preferred_master:STRING
 206    Name or address of the ICA server that _should_ be the master browser.
 207    Required.
 208 -T, --packet-timeout:INTEGER
 209    Time to wait for UDP packets (default 1 sec).
 210 -v, --verbose
 211    Debugging output.
 212 -h, --help
 213    This stuff.
 214
 215 ';
 216         support();
 217 }
 218
 219 sub version () {
 220         print_revision($PROGNAME,'$Revision: 1099 $ ');
 221         exit $ERRORS{'OK'};
 222 }
 223
 224 sub help () {
 225         print_help();
 226         exit $ERRORS{'OK'};
 227 }
 228