NAME

       Net::Frame::Layer - base class for all layer objects

DESCRIPTION

       This is the base class for all other layer modules. It provides those layers with
       inheritable attributes, methods, constants and useful subroutines.

ATTRIBUTES

       raw Stores the raw layer (as captured from the network, or packed to send to network).

       payload
           Stores what is not part of the layer, that is the encapsulated part to be decoded by
           upper layers.

       nextLayer
           User definable next layer. It may be used to define custom protocols.

METHODS

       new
       new (hash)
           Object constructor.

       layer
           Returns the string describing the layer (example: 'IPv4' for a Net::Frame::Layer::IPv4
           object).

       computeLengths
       computeChecksums
           Generally, when a layer is built, some attributes are not yet known until all layers
           that will be assembled are known. Those methods computes various lengths and checksums
           attributes found in a specific layer. Return 1 on success, undef otherwise. The usage
           depends from layer to layer, so see related documentation.

           Also note that in most cases, you will need to call computeLength before
           computeChecksums, because checksums may depend upon lengths.

       pack
           Packs all attributes into a raw format, in order to inject to network. Returns the raw
           packed string on success, undef otherwise. Result is stored into raw attribute.

       unpack
           Unpacks raw data from network and stores attributes into the object. Returns $self on
           success, undef otherwise.

       encapsulate
           Returns the next layer type (parsed from payload). This is the same string as returned
           by layer method.

       getLength
           Returns the layer length in bytes.

       getPayloadLength
           Returns the length of layer's payload in bytes.

       print
           Just returns a string in a human readable format describing attributes found in the
           layer.

       dump
           Just returns a string in hexadecimal format which is how the layer appears on the
           network.

USEFUL SUBROUTINES

       Load them: use Net::Frame::Layer qw(:subs);

       getHostIpv4Addr (hostname)
           Resolves IPv4 address of specified hostname.

       getHostIpv4Addrs (hostname)
           Same as above, but returns an array of IPv4 addresses.

       getHostIpv6Addr (hostname)
           Resolves IPv6 address of specified hostname.

       inet6Aton (IPv6 address)
           Takes IPv6 address and returns the network form.

       inet6Ntoa (IPv6 network form)
           Takes IPv6 address in network format, and returns the IPv6 human form.

       inetAton (IPv4 address)
       inetNtoa (IPv4 network form)
           Same as for IPv6, but for IPv4 addresses.

       convertMac (MAC network form)
           Takes a MAC address from network form, and returns the human form.

       getRandom16bitsInt
       getRandom32bitsInt
           Returns respectively a random 16 bits integer, and a random 32 bits integer.

       getRandomHighPort
           Returns a random high port (> 1024).

       inetChecksum (pseudo header format)
           Will take a frame in pseudo header format, and compute the INET checksum.

CONSTANTS

       Load them: use Net::Frame::Layer qw(:consts);

       NF_LAYER_NONE
       NF_LAYER_UNKNOWN
       NF_LAYER_NOT_AVAILABLE

AUTHOR

       Patrice <GomoR> Auffret

COPYRIGHT AND LICENSE

       Copyright (c) 2006-2014, Patrice <GomoR> Auffret

       You may distribute this module under the terms of the Artistic license.  See
       LICENSE.Artistic file in the source distribution archive.