Net::DNS::ToolKit::RR::AAAA - Resource Record Handler


Net-DNS-ToolKit documentation  | view source Contained in the Net-DNS-ToolKit distribution.

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NAME

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Net::DNS::ToolKit::RR::AAAA - Resource Record Handler

SYNOPSIS

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  DO NOT use Net::DNS::ToolKit::RR::AAAA
  DO NOT require Net::DNS::ToolKit::RR::AAAA

  Net::DNS::ToolKit::RR::AAAA is autoloaded by 
  class Net::DNS::ToolKit::RR and its methods
  are instantiated in a 'special' manner.

  use Net::DNS::ToolKit::RR;
  ($get,$put,$parse) = new Net::DNS::ToolKit::RR;

  ($newoff,$name,$type,$class,$ttl,$rdlength,
        $netaddr) = $get->AAAA(\$buffer,$offset);

  Note: the $get->AAAA method is normally called
  via:  @stuff = $get->next(\$buffer,$offset);

  ($newoff,@dnptrs)=$put->AAAA(\$buffer,$offset,\@dnptrs,
        $name,$type,$class,$ttl,$ipv6addr);

  $name,$TYPE,$CLASS,$TTL,$rdlength,$IP6addr) 
    = $parse->AAAA($name,$type,$class,$ttl,$rdlength,
        $ipv6addr);

DESCRIPTION

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Net::DNS::ToolKit::RR:AAAA appends an AAAA resource record to a DNS packet under construction, recovers an AAAA resource record from a packet being decoded, and converts the numeric/binary portions of the resource record to human readable form.

  Description from RFC1035.txt

  3.2.1. Format

  All RRs have the same top level format shown below:

                                    1  1  1  1  1  1
      0  1  2  3  4  5  6  7  8  9  0  1  2  3  4  5
    +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    |                      NAME                     |
    +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    |                      TYPE                     |
    +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    |                     CLASS                     |
    +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    |                      TTL                      |
    +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    |                   RDLENGTH                    |
    +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--|
    |                     RDATA                     |
    +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+

  NAME  an owner name, i.e., the name of the node to which this
        resource record pertains.

  TYPE  two octets containing one of the RR TYPE codes.

  CLASS two octets containing one of the RR CLASS codes.

  TTL   a 32 bit signed integer that specifies the time interval
        that the resource record may be cached before the source
        of the information should again be consulted.  Zero
        values are interpreted to mean that the RR can only be
        used for the transaction in progress, and should not be
        cached.  For example, SOA records are always distributed
        with a zero TTL to prohibit caching.  Zero values can
        also be used for extremely volatile data.

  RDLENGTH an unsigned 16 bit integer that specifies the length
        in octets of the RDATA field.

  RDATA a variable length string of octets that describes the
        resource.  The format of this information varies
        according to the TYPE and CLASS of the resource record.

  Description from RFC1884.txt

                  AAAA RDATA format
                                    1  1  1  1  1  1
      0  1  2  3  4  5  6  7  8  9  0  1  2  3  4  5
    +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    |                                               |
    +                                               +
    |                  128 bit                      |
    +                IPv6 ADDRESS                   +
    |                                               |
    +                                               +
    |                                               |
    +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+

* @stuff = $get->AAAA(\$buffer,$offset);
  Get the contents of the resource record.

  USE: @stuff = $get->next(\$buffer,$offset);

  where: @stuff = (
  $newoff $name,$type,$class,$ttl,$rdlength,
  $ipv6addr );

All except the last item, $ipv6addr, is provided by the class loader, Net::DNS::ToolKit::RR. The code in this method knows how to retrieve $ipv6addr.

  input:        pointer to buffer,
                offset into buffer
  returns:      offset to next resource,
                @common RR elements,
                128 bit IPv6 address 

  NOTE: convert IPv6 address to hex or hex + dotquad
        using Net::DNS::ToolKit::ipv6_n2x or ipv6_ntd
	respectively.

* ($newoff,@dnptrs)=$put->AAAA(\$buffer,$offset,\@dnptrs, @common,$ipv6addr);

Append an AAAA record to $buffer.

  where @common = (
	$name,$type,$class,$ttl);

The method will insert the $rdlength and $ipv6addr, then pass through the updated pointer to the array of compressed names

The class loader, Net::DNS::ToolKit::RR, inserts the @common elements and returns updated @dnptrs. This module knows how to insert its RDATA and calculate the $rdlength.

  input:        pointer to buffer,
                offset (normally end of buffer), 
                pointer to compressed name array,
                @common RR elements,
                128 bit IPv6 address
  output:       offset to next RR,
                new compressed name pointer array,
           or   empty list () on error.

* (@COMMON,$IPaddr) = $parse->AAAA(@common,$ipv6addr);

Converts binary/numeric field data into human readable form. The common RR elements are supplied by the class loader, Net::DNS::ToolKit::RR. This module knows how to parse its RDATA.

        EXAMPLE
Common is: name,$type,$class,$ttl,$rdlength

  name       '.' is appended
  type       numeric to text 
  class      numeric to text 
  ttl        numeric to text
  rdlength   is a number
  rdata      RR specific conversion

Resource Record AAAA returns $rdata containing a 128 bit IPv6 address. The parse operation would be:

input:

  name       foo.bar.com
  type       1  
  class      1  
  ttl        123
  rdlength   4  
  rdata      a 128 bit IPv6 address

output:

  name       foo.bar.com
  type       T_AAAA
  class      C_IN
  ttl        2m 3s
  rdlength   16
  rdata      FE:0:0:0:1:2:3:4

DEPENDENCIES

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        Net::DNS::ToolKit
        Net::DNS::Codes

EXPORT

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	none

AUTHOR

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Michael Robinton <michael@bizsystems.com>

COPYRIGHT

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See also:

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Net::DNS::Codes(3), Net::DNS::ToolKit(3)


Net-DNS-ToolKit documentation  | view source Contained in the Net-DNS-ToolKit distribution.