Net::Packet::IGMPv4 - Internet Group Management Protocol v4 layer 4 object

   use Net::Packet::Consts qw(:igmpv4);
   require Net::Packet::IGMPv4;

   # Build a layer
   my $layer = Net::Packet::IGMPv4->new(
      version      => 2,
      type         => NP_IGMPv4_v2_TYPE_QUERY,
      maxRespTime  => 10,
      checksum     => 0,
      groupAddress => NP_IGMPv4_GROUP_ADDRESS_ALL_HOSTS,
   );
   $layer->pack;

   print 'RAW: '.unpack('H*', $layer->raw)."\n";

   # Read a raw layer
   my $layer = Net::Packet::IGMPv4->new(raw => $raw);

   print $layer->print."\n";
   print 'PAYLOAD: '.unpack('H*', $layer->payload)."\n"
      if $layer->payload;

#
# $Id: IGMPv4.pm 1640 2009-11-09 17:58:27Z gomor $
#
package Net::Packet::IGMPv4;
use strict;
use warnings;

require Net::Packet::Layer4;
our @ISA = qw(Net::Packet::Layer4);

use Net::Packet::Consts qw(:igmpv4 :layer);
use Net::Packet::Utils qw(inetNtoa inetAton);
require Bit::Vector;

our @AS = qw(
   version
   type
   maxRespTime
   unused
   checksum
   groupAddress
);
__PACKAGE__->cgBuildIndices;
__PACKAGE__->cgBuildAccessorsScalar(\@AS);

#no strict 'vars';

sub new {
   shift->SUPER::new(
      version      => 2,
      type         => NP_IGMPv4_v2_TYPE_QUERY,
      maxRespTime  => 10,
      unused       => 0,
      checksum     => 0,
      groupAddress => NP_IGMPv4_GROUP_ADDRESS_ALL_HOSTS,
      @_,
   );
}

sub getLength { NP_IGMPv4_HDR_LEN }

sub pack {
   my $self = shift;

   if ($self->version == 1) {
      $self->raw($self->SUPER::pack('CCna4',
         $self->version, $self->type, $self->unused, $self->checksum,
         inetAton($self->groupAddress),
      )) or return undef;
   }
   else {
      $self->raw($self->SUPER::pack('CCna4',
         $self->type, $self->maxRespTime, $self->checksum,
         inetAton($self->groupAddress),
      )) or return undef;
   }

   1;
}

sub unpack {
   my $self = shift;

   my ($versionType, $unused, $checksum, $groupAddress, $payload) =
      $self->SUPER::unpack('CCna4 a*', $self->raw)
         or return undef;

   # It is a version 2 of the protocol spec
   if ($unused) {
      $self->version(2);
      $self->type($versionType);
      $self->maxRespTime($unused / 10);
   }
   # Or version 1
   else {
      my $v8 = Bit::Vector->new_Dec(8, $versionType);
      $self->version($v8->Chunk_Read(4, 0));
      $self->type($v8->Chunk_Read(4, 4));
      $self->unused($unused);
   }

   $self->checksum($checksum);
   $self->groupAddress(inetNtoa($groupAddress));

   $self->payload($payload);

   1;
}

sub encapsulate {
   my $types = {
      NP_LAYER_NONE() => NP_LAYER_NONE(),
   };

   $types->{NP_LAYER_NONE()} || NP_LAYER_UNKNOWN();
}

sub print {
   my $self = shift;

   my $l = $self->layer;
   my $i = $self->is;
   if ($self->version == 1) {
      sprintf "$l:+$i: version:%d  type:0x%01x  unused:0x%02x  ".
              "checksum:0x%04x\n".
              "$l: $i: groupAddress:%s",
                 $self->version, $self->type, $self->unused, $self->checksum,
                 $self->groupAddress;
   }
   else {
      sprintf "$l:+$i: version:%d  type:0x%02x  maxRespTime:%d  ".
              "checksum:0x%04x\n".
              "$l: $i: groupAddress:%s",
                 $self->version, $self->type, $self->maxRespTime,
                 $self->checksum, $self->groupAddress;
   }
}

1;

__END__