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
:nofqdn
);
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();
Will also return an ipV4 or ipV6 representation of a
resolvable Fully Qualified Domanin Name (FQDN).
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, [ $mask]])"
- "->new6FFFF([$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 three 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.
new6FFFF specifically returns an IPv4 address in IPv6 format according to
RFC4291
new6 ::xxxx:xxxx
new6FFFF ::FFFF:xxxx:xxxx
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.
If called with an empty string as the argument, returns 'undef'
$addr can be any of the following and possibly more...
n.n
n.n/mm
n.n mm
n.n.n
n.n.n/mm
n.n.n mm
n.n.n.n
n.n.n.n/mm 32 bit cidr notation
n.n.n.n mm
n.n.n.n/m.m.m.m
n.n.n.n m.m.m.m
loopback, localhost, broadcast, any, default
x.x.x.x/host
0xABCDEF, 0b111111000101011110, (or a bcd number)
a netaddr as returned by 'inet_aton'
Any RFC1884 notation
::n.n.n.n
::n.n.n.n/mmm 128 bit cidr notation
::n.n.n.n/::m.m.m.m
::x:x
::x:x/mmm
x:x:x:x:x:x:x:x
x:x:x:x:x:x:x:x/mmm
x:x:x:x:x:x:x:x/m:m:m:m:m:m:m:m any RFC1884 notation
loopback, localhost, unspecified, any, default
::x:x/host
0xABCDEF, 0b111111000101011110 within the limits
of perl's number resolution
123456789012 a 'big' bcd number (bigger than perl likes)
and Math::BigInt
A Fully Qualified Domain Name which returns an ipV4 address or an ipV6
address, embodied in that order. This previously undocumented feature may
be disabled with:
use NetAddr::IP::Lite ':nofqdn';
If called with no arguments, 'default' is assumed.
If called with and empty string as the argument, 'undef' is returned;
- "->broadcast()"
- Returns a new object referring to the broadcast address of a given subnet.
The broadcast address has all ones in all the bit positions where the
netmask has zero bits. This is normally used to address all the hosts in a
given subnet.
- "->network()"
- Returns a new object referring to the network address of a given subnet. A
network address has all zero bits where the bits of the netmask are zero.
Normally this is used to refer to a subnet.
- "->addr()"
- Returns a scalar with the address part of the object as an IPv4 or IPv6
text string as appropriate. This is useful for printing or for passing the
address part of the NetAddr::IP::Lite object to other components that
expect an IP address. If the object is an ipV6 address or was created
using ->new6($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.
- C->is_rfc1918()>
- Returns true when $me is an RFC 1918 address.
10.0.0.0 - 10.255.255.255 (10/8 prefix)
172.16.0.0 - 172.31.255.255 (172.16/12 prefix)
192.168.0.0 - 192.168.255.255 (192.168/16 prefix)
- "->first()"
- Returns a new object representing the first usable IP address within the
subnet (ie, the first host address).
- "->last()"
- Returns a new object representing the last usable IP address within the
subnet (ie, one less than the broadcast address).
- "->nth($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
:nofqdn
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 - 2014.
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.,
51 Franklin Street, Fifth Floor
Boston, MA 02110-1301 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)