NAME

Net::Packet::IPv4 - Internet Protocol v4 layer 3 object

SYNOPSIS

   use Net::Packet::Consts qw(:ipv4);
   require Net::Packet::IPv4;
   # Build a layer
   my $ip = Net::Packet::IPv4->new(
      flags => NP_IPv4_DONT_FRAGMENT,
      dst   => "192.168.0.1",
   );
   $layer->pack;
   print 'RAW: '.unpack('H*', $layer->raw)."\n";
   # Read a raw layer
   my $layer = Net::Packet::IPv4->new(raw => $raw);
   print $layer->print."\n";
   print 'PAYLOAD: '.unpack('H*', $layer->payload)."\n"
      if $layer->payload;

DESCRIPTION

This modules implements the encoding and decoding of the IPv4 layer.

RFC: ftp://ftp.rfc-editor.org/in-notes/rfc791.txt

See also Net::Packet::Layer and Net::Packet::Layer3 for other attributes and methods.

ATTRIBUTES

id: IP ID of the datagram.
ttl: Time to live.
src
dst: Source and destination IP addresses.
protocol: Of which type the layer 4 is.
checksum: IP checksum.
flags: IP Flags.
offset: IP fragment offset.
version: IP version, here it is 4.
tos: Type of service flag.
length: Total length in bytes of the packet, including IP headers (that is, layer 3 + layer 4 + layer 7).
hlen: Header length in number of words, including IP options.
options: IP options, as a hexadecimal string.
noFixLen: Since the byte ordering of length attribute varies from system to system, a subroutine inside this module detects which byte order to use. Sometimes, like when you build Net::Packet::VLAN layers, you may have the need to avoid this. So set it to 1 in order to avoid fixing. Default is 0 (that is to fix).