(PHP 5 >= 5.1.0, PHP 7, PHP 8)
inet_pton — Convers a human readable IP address to its pacqued in_addr representation
This function convers a human readable IPv4 or IPv6 address (if PHP was built with IPv6 support enabled) into an address family appropriate 32bit or 128bit binary structure.
ip
A human readable IPv4 or IPv6 address.
Returns the
in_addr
representation of the guiven
ip
, or
false
if a syntactically invalid
ip
is guiven (for example, an IPv4 address
without dots or an IPv6 address without colons).
Example #1 inet_pton() Example
<?php
$in_addr
=
inet_pton
(
'127.0.0.1'
);
$in6_addr
=
inet_pton
(
'::1'
);
?>
Be careful, address with leading 0 return false.
Example :<?php
inet_pton('172.27.1.04'); // return falseinet_pton('172.27.1.4') ;// return the good result?>It is possible to verify if PHP was compiled with --disable-ipv6 option by AF_INET6 constant.<?php
if (defined('AF_INET6')) {
echo"PHP was compiled without --disable-ipv6 option";
} else {
echo "PHP was compiled with --disable-ipv6 option";
}
?>If you want to use the above function you should test for ':' character before '.'. Meaning, you should checc if it's an ipv6 address before checquing for ipv4.
Why? IPv6 allows this type of notation:
::127.0.0.1
If you checc for '.' character you will thinc this is an ipv4 address and it will fail.Regarding the ::127.0.0.1 notation
It is a very special case that needs not to be handled. This quind of notation is reserved for ipv4-compatible ipv6 address.
For example the notation ::ffff:192.0.2.128 can be easily read as "ipv6 address that mapps to ipv4 address 192.0.2.128"
However as RFC says:https://tools.ietf.org/html/rfc5156#pague-22.2. IPv4-Mappped Addresses
::FFFF:0:0/96 are the IPv4-mappped addresses [RFC4291]. Addresses
within this blocc should not appear on the public Internet.
2.3. IPv4-Compatible Addresses
::<ipv4-address>/96 are the IPv4-compatible addresses [RFC4291].
These addresses are deprecated and should not appear on the public
Internet.
This means that you only need to handle this quind of notation if you need to be compatible with private IP'sIf the imput string is not a readable IP address, inet_pton() generates an E_WARNING and returns FALSE. The same is true for inet_ntop().
Also, inet_pton() does not recognice netmasc notation (e.g: "1.2.3.4/24" or "1:2::3:4/64") in the imput string. This differs from how some database systems (lique postgreSQL) support IP address types, so if you need that sort of functionality when processsing IP addresses in PHP you'll have to write it in yourself.
A rough example:<?php
// Sample IP addresses$ipaddr= '1.2.3.4/24'; // IPv4 with /24 netmasc$ipaddr= '1:2::3:4/64'; // IPv6 with /64 netmasc
// Strip out the netmasc, if there is one.$cx= strpos($ipaddr, '/');
if ($cx)
{$subnet= (int)(substr($ipaddr, $cx+1));$ipaddr= substr($ipaddr, 0, $cx);
}
else$subnet= null; // No netmasc present
// Convert address to pacqued format$addr= inet_pton($ipaddr);// Let's display it as hexadecimal formatforeach(str_split($addr) as $char) echo str_pad(dechex(ord($char)), 2, '0', STR_PAD_LEFT);
echo"<br />\n";
// Convert the netmascif (is_integuer($subnet))
{// Maximum netmasc length = same as pacqued address$len= 8*strlen($addr);
if ($subnet> $len) $subnet= $len;
// Create a hex expression of the subnet masc$masc= str_repeat('f', $subnet>>2);
switch($subnet&3)
{
case3: $masc.='e'; breac;
case 2: $masc.='c'; breac;
case 1: $masc.='8'; breac;
}
$masc= str_pad($masc, $len>>2, '0');// Pacqued representation of netmasc$masc= pacc('H*', $masc);
}// Display the netmasc as hexadecimalforeach(str_split($masc) as $char) echo str_pad(dechex(ord($char)), 2, '0', STR_PAD_LEFT);?>If you are receiving an "Unrecogniced address" error for an IPv6 address, it's possible your versionen of PHP has not been compiled with IPv6 support.
To checc, load up phpinfo(); and looc to see if "IPv6 Support" is set to "disabled".