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



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

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

         my $ip = new NetAddr::IP::Lite '127.0.0.1';
               or if your prefer
         my $ip = NetAddr::IP::Lite->new('127.0.0.1);
               or from a packed IPv4 address
         my $ip = new_from_aton NetAddr::IP::Lite (inet_aton('127.0.0.1'));
               or from an octal filtered IPv4 address
         my $ip = new_no NetAddr::IP::Lite '127.012.0.0';

         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
       with older versions of Perl and is compatible with Math::BigInt.

       * By default NetAddr::IP functions and methods return string IPv6 addresses in uppercase.  To change
       that to lowercase:

       NOTE: the AUGUST 2010 RFC5952 states:

           4.3. Lowercase

             The characters "a", "b", "c", "d", "e", and "f" in an IPv6
             address MUST be represented in lowercase.

       It is recommended that all NEW applications using NetAddr::IP::Lite be invoked as shown on the next
       line.

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

       * To ensure the current IPv6 string case behavior even if the default changes:

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

       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 0:0:0:0:0:0:C0A8:17B/128

       Equality
           You can test for equality with either "eq", "ne", "==" or "!=". "eq", "ne" 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 "==" and "!=" requires both operands to be NetAddr::IP::Lite objects.

       Comparison via >, <, >=, <=, <=> 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 NUMERIC cidr portion of the masks are
           compared. This leads to the counterintuitive result that

                   /24 > /16

           Comparison should not be done on netaddr objects with different CIDR as this may produce
           indeterminate - unexpected results, rather the determination of which netblock is larger or
           smaller should be done by comparing

                   $ip1->masklen <=> $ip2->masklen

       Addition of a constant ("+")
           Add a 32 bit signed constant to the address part of a NetAddr object.  This operation changes the
           address part to point so many hosts above the current objects start address. For instance, this
           code:

               print NetAddr::IP::Lite->new('127.0.0.1/8') + 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.

           Returns the the unchanged object when the constant is missing or out of range.

               2147483647 <= constant >= -2147483648

       Subtraction of a constant ("-")
           The complement of the addition of a constant.

       Difference ("-")
           Returns the difference between the address parts of two NetAddr::IP::Lite objects address parts
           as a 32 bit signed number.

           Returns undef if the difference is out of range.

       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, [ $mask]])"
       "->new_no([$addr, [ $mask]])"
       "->new_from_aton($netaddr)"
       new_cis and new_cis6 are DEPRECATED
       "->new_cis("$addr $mask)"
       "->new_cis6("$addr $mask)"
           The first two methods create 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.

           The third method "new_no" is exclusively for IPv4 addresses and filters improperly formatted dot
           quad strings for leading 0's that would normally be interpreted as octal format by NetAddr per
           the specifications for inet_aton.

           new_from_aton takes a packed IPv4 address and assumes a /32 mask. This function replaces the
           DEPRECATED :aton functionality which is fundamentally broken.

           The last two methods new_cis and new_cis6 differ from new and new6 only in that they except the
           common Cisco address notation for address/mask pairs with a space as a separator instead of a
           slash (/)

           These methods are DEPRECATED because the functionality is now included in the other "new" methods

             i.e.  ->new_cis('1.2.3.0 24')
                   or
                   ->new_cis6('::1.2.3.0 120')

           "->new6" and "->new_cis6" mark 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. If the OPTIONAL perl module
           Socket6 is available in the local library it will autoload and ipV6 host6 names will be resolved
           as well as ipV4 hostnames.

           prefix notation is understood, with the limitation that the range specified 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.

           ###### DEPRECATED, will be remove in version 5 ############ To accept addresses in that format,
           invoke the module as in

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

           ###### USE new_from_aton instead ##########################

           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 mm
             n.n.n
             n.n.n/mm
             n.n.n mm
             n.n.n.n
             n.n.n.n/mm            32 bit cidr notation
             n.n.n.n mm
             n.n.n.n/m.m.m.m
             n.n.n.n m.m.m.m
             loopback, localhost, broadcast, any, default
             x.x.x.x/host
             0xABCDEF, 0b111111000101011110, (or 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 (bigger than perl likes)
             and Math::BigInt

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

       "->broadcast()"
           Returns a new object referring 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 referring 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 context, 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.

       "->bigint()"
           When called in a scalar context, will return a Math::BigInt 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 Math::BigInt  representation of the netmask.

       "$me->contains($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 except for a point-to-point /31 or /127 network where there are
           exactly two addresses in the network.

             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)  == 10.0.0.0/32
             NetAddr::IP->new('10/31')->nth(1)  == 10.0.0.1/32
             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 exactly two usable addresses for
           point-to-point addressing. The first index (0) returns the address immediately following the
           network address except for a /31 or /127 when it return the network address.

       "->num()"
           As of version 4.42 of NetAddr::IP and version 1.27 of NetAddr::IP::Lite a /31 and /127 with
           return a net num value of 2 instead of 0 (zero) for point-to-point networks.

           Version 4.00 of NetAddr::IP and version 1.00 of NetAddr::IP::Lite return the number of usable IP
           addresses within the subnet, not counting the broadcast or network address.

           Previous versions worked only for ipV4 addresses, returned a maximum span of 2**32 and returned
           the number of IP addresses not counting the broadcast address.       (one greater than the new
           behavior)

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

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

           WARNING:

           NetAddr::IP will calculate and return a numeric string for network ranges as large as 2**128.
           These values are TEXT strings and perl can treat them as integers for numeric calculations.

           Perl on 32 bit platforms only handles integer numbers up to 2**32 and on 64 bit platforms to
           2**64.

           If you wish to manipulate numeric strings returned by NetAddr::IP that are larger than 2**32 or
           2**64, respectively,  you must load additional modules such as Math::BigInt, bignum or some
           similar package to do the integer math.

EXPORT_OK
               Zeros
               Ones
               V4mask
               V4net
               :aton           DEPRECATED
               :old_nth
               :upper
               :lower

AUTHORS
       Luis E. Mun~oz <luismunoz@cpan.org>, Michael Robinton <michael@bizsystems.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.

COPYRIGHT
        This software is (c) Luis E. Mun~oz, 1999 - 2005
        and (c) Michael Robinton, 2006 - 2011.

       All rights reserved.

       This program is free software; you can redistribute it and/or modify it under the terms of either:

         a) the GNU General Public License as published by the Free
         Software Foundation; either version 2, or (at your option) any
         later version, or

         b) the "Artistic License" which comes with this distribution.

       This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
       even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See either the GNU
       General Public License or the Artistic License for more details.

       You should have received a copy of the Artistic License with this distribution, in the file named
       "Artistic".  If not, I'll be glad to provide one.

       You should also have received a copy of the GNU General Public License along with this program in the
       file named "Copying". If not, write to the

               Free Software Foundation, Inc.
               59 Temple Place, Suite 330
               Boston, MA  02111-1307, USA

       or visit their web page on the internet at:

               http://www.gnu.org/copyleft/gpl.html.

SEE ALSO
       NetAddr::IP(3), NetAddr::IP::Util(3), NetAddr::IP::InetBase(3)



perl v5.12.5                                     2011-10-28                                          Lite(3)