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Lite(3pm)             User Contributed Perl Documentation            Lite(3pm)



NAME
       NetAddr::IP::Lite - Manages IPv4 and IPv6 addresses and subnets

SYNOPSIS
         use NetAddr::IP::Lite qw(
               Zeros
               Ones
               V4mask
               V4net
               :aton
               :old_nth
         );

         my $ip = new NetAddr::IP::Lite '127.0.0.1';

         print "The address is ", $ip->addr, " with mask ", $ip->mask, "\n" ;

         if ($ip->within(new NetAddr::IP::Lite "127.0.0.0", "255.0.0.0")) {
             print "Is a loopback address\n";
         }

                                       # This prints 127.0.0.1/32
         print "You can also say $ip...\n";

         The following four functions return ipV6 representations of:

         ::                                       = Zeros();
         FFFF:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF: = Ones();
         FFFF:FFFF:FFFF:FFFF:FFFF:FFFF::          = V4mask();
         ::FFFF:FFFF                              = V4net();

INSTALLATION
       Un-tar the distribution in an appropriate directory and type:

               perl Makefile.PL
               make
               make test
               make install

       NetAddr::IP::Lite depends on NetAddr::IP::Util which installs by
       default with its primary functions compiled using Perl's XS extensions
       to build a 'C' library. If you do not have a 'C' complier available or
       would like the slower Pure Perl version for some other reason, then
       type:

               perl Makefile.PL -noxs
               make
               make test
               make install

DESCRIPTION
       This module provides an object-oriented abstraction on top of IP
       addresses or IP subnets, that allows for easy manipulations. Most of
       the operations of NetAddr::IP are supported. This module will work
       older versions of Perl and does not use Math::BigInt.

       The internal representation of all IP objects is in 128 bit IPv6
       notation.  IPv4 and IPv6 objects may be freely mixed.

       The supported operations are described below:

       Overloaded Operators

       Assignment ("=")
           Has been optimized to copy one NetAddr::IP::Lite object to another
           very quickly.

       "->>copy()"
           The assignment ("=") operation is only put in to operation when the
           copied object is further mutated by another overloaded operation.
           See overload SPECIAL SYMBOLS FOR "use overload" for details.

           "->>copy()" actually creates a new object when called.

       Stringification
           An object can be used just as a string. For instance, the following
           code

                   my $ip = new NetAddr::IP::Lite '192.168.1.123';
                   print "$ip\n";

           Will print the string 192.168.1.123/32.

                   my $ip = new6 NetAddr::IP::Lite '192.168.1.123';
                   print "$ip\n";

           Will print the string

       Equality
           You can test for equality with either "eq" or "==". "eq" allows the
           comparison with arbitrary strings as well as NetAddr::IP::Lite
           objects. The following example:

               if (NetAddr::IP::Lite->new('127.0.0.1','255.0.0.0') eq '127.0.0.1/8')
                  { print "Yes\n"; }

           Will print out "Yes".

           Comparison with "==" requires both operands to be NetAddr::IP::Lite
           objects.

           In both cases, a true value is returned if the CIDR representation
           of the operands is equal.

       Comparison via >&gt;, <&lt;, >&gt;=, <&lt;=, <&lt;=>&gt; and "cmp"
           Internally, all network objects are represented in 128 bit format.
           The numeric representation of the network is compared through the
           corresponding operation. Comparisons are tried first on the address
           portion of the object and if that is equal then the cidr portion of
           the masks are compared.

       Addition of a constant
           Adding a constant to a NetAddr::IP::Lite object changes its address
           part to point to the one so many hosts above the start address. For
           instance, this code:

               print NetAddr::IP::Lite->new('127.0.0.1') + 5;

           will output 127.0.0.6/8. The address will wrap around at the
           broadcast back to the network address. This code:

               print NetAddr::IP::Lite->new('10.0.0.1/24') + 255;

           outputs 10.0.0.0/24.

       Substraction of a constant
           The complement of the addition of a constant.

       Auto-increment
           Auto-incrementing a NetAddr::IP::Lite object causes the address
           part to be adjusted to the next host address within the subnet. It
           will wrap at the broadcast address and start again from the network
           address.

       Auto-decrement
           Auto-decrementing a NetAddr::IP::Lite object performs exactly the
           opposite of auto-incrementing it, as you would expect.

       Methods

       "->new([$addr, [ $mask|IPv6 ]])"
       "->new6([$addr, [ $mask]])"
           These methods creates a new address with the supplied address in
           $addr and an optional netmask $mask, which can be omitted to get a
           /32 or /128 netmask for IPv4 / IPv6 addresses respectively

           "->new6" marks the address as being in ipV6 address space even if
           the format would suggest otherwise.

             i.e.  ->new6('1.2.3.4') will result in ::102:304

             addresses submitted to ->new in ipV6 notation will
             remain in that notation permanently. i.e.
                   ->new('::1.2.3.4') will result in ::102:304
             whereas new('1.2.3.4') would print out as 1.2.3.4

             See "STRINGIFICATION" below.

           $addr can be almost anything that can be resolved to an IP address
           in all the notations I have seen over time. It can optionally
           contain the mask in CIDR notation.

           prefix notation is understood, with the limitation that the range
           speficied by the prefix must match with a valid subnet.

           Addresses in the same format returned by "inet_aton" or
           "gethostbyname" can also be understood, although no mask can be
           specified for them. The default is to not attempt to recognize this
           format, as it seems to be seldom used.

           To accept addresses in that format, invoke the module as in

             use NetAddr::IP::Lite ':aton'

           If called with no arguments, 'default' is assumed.

           $addr can be any of the following and possibly more...

             n.n
             n.n/mm
             n.n.n
             n.n.n/mm
             n.n.n.n
             n.n.n.n/mm            32 bit cidr notation
             n.n.n.n/m.m.m.m
             loopback, localhost, broadcast, any, default
             x.x.x.x/host
             0xABCDEF, 0b111111000101011110, (a bcd number)
             a netaddr as returned by 'inet_aton'

           Any RFC1884 notation

             ::n.n.n.n
             ::n.n.n.n/mmm         128 bit cidr notation
             ::n.n.n.n/::m.m.m.m
             ::x:x
             ::x:x/mmm
             x:x:x:x:x:x:x:x
             x:x:x:x:x:x:x:x/mmm
             x:x:x:x:x:x:x:x/m:m:m:m:m:m:m:m any RFC1884 notation
             loopback, localhost, unspecified, any, default
             ::x:x/host
             0xABCDEF, 0b111111000101011110 within the limits
             of perl's number resolution
             123456789012  a 'big' bcd number i.e. Math::BigInt

           If called with no arguments, 'default' is assumed.

       "->broadcast()"
           Returns a new object refering to the broadcast address of a given
           subnet. The broadcast address has all ones in all the bit positions
           where the netmask has zero bits. This is normally used to address
           all the hosts in a given subnet.

       "->network()"
           Returns a new object refering to the network address of a given
           subnet. A network address has all zero bits where the bits of the
           netmask are zero. Normally this is used to refer to a subnet.

       "->addr()"
           Returns a scalar with the address part of the object as an IPv4 or
           IPv6 text string as appropriate. This is useful for printing or for
           passing the address part of the NetAddr::IP::Lite object to other
           components that expect an IP address. If the object is an ipV6
           address or was created using ->new6($ip) it will be reported in
           ipV6 hex format otherwise it will be reported in dot quad format
           only if it resides in ipV4 address space.

       "->mask()"
           Returns a scalar with the mask as an IPv4 or IPv6 text string as
           described above.

       "->masklen()"
           Returns a scalar the number of one bits in the mask.

       "->bits()"
           Returns the width of the address in bits. Normally 32 for v4 and
           128 for v6.

       "->version()"
           Returns the version of the address or subnet. Currently this can be
           either 4 or 6.

       "->cidr()"
           Returns a scalar with the address and mask in CIDR notation. A
           NetAddr::IP::Lite object stringifies to the result of this
           function.  (see comments about ->new6() and ->addr() for output
           formats)

       "->aton()"
           Returns the address part of the NetAddr::IP::Lite object in the
           same format as the "inet_aton()" or "ipv6_aton" function
           respectively. If the object was created using ->new6($ip), the
           address returned will always be in ipV6 format, even for addresses
           in ipV4 address space.

       "->range()"
           Returns a scalar with the base address and the broadcast address
           separated by a dash and spaces. This is called range notation.

       "->numeric()"
           When called in a scalar context, will return a numeric
           representation of the address part of the IP address. When called
           in an array contest, it returns a list of two elements. The first
           element is as described, the second element is the numeric
           representation of the netmask.

           This method is essential for serializing the representation of a
           subnet.

       "$me->contains($other)"
           Returns true when $me completely contains $other. False is returned
           otherwise and "undef" is returned if $me and $other are not both
           "NetAddr::IP::Lite" objects.

       "$me->within($other)"
           The complement of "->contains()". Returns true when $me is
           completely contained within $other, undef if $me and $other are not
           both "NetAddr::IP::Lite" objects.

       "->first()"
           Returns a new object representing the first usable IP address
           within the subnet (ie, the first host address).

       "->last()"
           Returns a new object representing the last usable IP address within
           the subnet (ie, one less than the broadcast address).

       "->nth($index)"
           Returns a new object representing the n-th usable IP address within
           the subnet (ie, the n-th host address).  If no address is available
           (for example, when the network is too small for $index hosts),
           "undef" is returned.

           Version 4.00 of NetAddr::IP and version 1.00 of NetAddr::IP::Lite
           implements "->nth($index)" and "->num()" exactly as the
           documentation states.  Previous versions behaved slightly
           differently and not in a consistent manner.

           To use the old behavior for "->nth($index)" and "->num()":

             use NetAddr::IP::Lite qw(:old_nth);

             old behavior:
             NetAddr::IP->new('10/32')->nth(0) == undef
             NetAddr::IP->new('10/32')->nth(1) == undef
             NetAddr::IP->new('10/31')->nth(0) == undef
             NetAddr::IP->new('10/31')->nth(1) == 10.0.0.1/31
             NetAddr::IP->new('10/30')->nth(0) == undef
             NetAddr::IP->new('10/30')->nth(1) == 10.0.0.1/30
             NetAddr::IP->new('10/30')->nth(2) == 10.0.0.2/30
             NetAddr::IP->new('10/30')->nth(3) == 10.0.0.3/30

           Note that in each case, the broadcast address is represented in the
           output set and that the 'zero'th index is alway undef.

             new behavior:
             NetAddr::IP->new('10/32')->nth(0)  == 10.0.0.0/32
             NetAddr::IP->new('10.1/32'->nth(0) == 10.0.0.1/32
             NetAddr::IP->new('10/31')->nth(0)  == undef
             NetAddr::IP->new('10/31')->nth(1)  == undef
             NetAddr::IP->new('10/30')->nth(0) == 10.0.0.1/30
             NetAddr::IP->new('10/30')->nth(1) == 10.0.0.2/30
             NetAddr::IP->new('10/30')->nth(2) == undef

           Note that a /32 net always has 1 usable address while a /31 has
           none since it has a network and broadcast address, but no host
           addresses. The first index (0) returns the address immediately
           following the network address.

       "->num()"
           Version 4.00 of NetAddr::IP and version 1.00 of NetAddr::IP::Lite
           Returns the number of usable addresses IP addresses within the
           subnet, not counting the broadcast or network address. Previous
           versions returned th number of IP addresses not counting the
           broadcast address.

           To use the old behavior for "->nth($index)" and "->num()":

             use NetAddr::IP::Lite qw(:old_nth);

EXPORT_OK
               Zero
               Ones
               V4mask
               V4net
               :aton
               :old_nth

AUTHOR
       Luis E. MuA~Xoz <luismunozATcpan.org>, Michael Robinton
       <michaelATbizsystems.com>

WARRANTY
       This software comes with the  same warranty as perl itself (ie, none),
       so by using it you accept any and all the liability.

LICENSE
       This software is (c) Luis E. MuA~Xoz, 1999 - 2005, and (c) Michael
       Robinton, 2006.  It can be used under the terms of the perl artistic
       license provided that proper credit for the work of the author is
       preserved in the form of this copyright notice and license for this
       module.

SEE ALSO
       perl(1), NetAddr::IP(3), NetAddr::IP::Util(3)



perl v5.10.0                      2008-05-02                         Lite(3pm)