inet_pton

(PHP 5 >= 5.1.0, PHP 7, PHP 8)

inet_pton — Converts a human readable IP address to its packed in_addr representation

说明

inet_pton ( string $ip ) : string|false

This function converts 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.

参数

ip: A human readable IPv4 or IPv6 address.

返回值

Returns the in_addr representation of the given ip, or false if a syntactically invalid ip is given (for example, an IPv4 address without dots or an IPv6 address without colons).

范例

Example #1 inet_pton() Example


<?php
$in_addr = inet_pton('127.0.0.1');
 
$in6_addr = inet_pton('::1');
?>

参见

ip2long() - 将 IPV4 的字符串互联网协议转换成长整型数字
long2ip() - 将长整型转化为字符串形式带点的互联网标准格式地址（IPV4）
inet_ntop() - Converts a packed internet address to a human readable representation

User Contributed Notes

admin at hanzlsoft dot eu 22-Jan-2021 12:33


Regarding the ::127.0.0.1 notation



It is a very special case that needs not to be handled. This kind 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 maps to ipv4 address 192.0.2.128"



However as RFC says:

https://tools.ietf.org/html/rfc5156#page-2



2.2.  IPv4-Mapped Addresses



   ::FFFF:0:0/96 are the IPv4-mapped addresses [RFC4291].  Addresses

   within this block 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 kind of notation if you need to be compatible with private IP's

tobias 06-May-2016 05:04


Oh my god:



0000:0000:0000:0000:0000:0000:0127:2258

becomes '"X.



Do not forget to escape it

dave at php dot net 06-Mar-2015 04:07


If you are receiving an "Unrecognized address" error for an IPv6 address, it's possible your version of PHP has not been compiled with IPv6 support.



To check, load up phpinfo(); and look to see if "IPv6 Support" is set to "disabled".

TuRn3r 02-Jun-2014 03:26


Be careful, address with leading 0 return false.



Example : 

<?php

inet_pton('172.27.1.04'); // return false

inet_pton('172.27.1.4') ;// return the good result

?>

francis dot besset at gmail dot com 15-Jul-2011 01:45


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";

}



?>

strata_ranger at hotmail dot com 13-Sep-2009 10:51


If the input 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 recognize netmask notation (e.g: "1.2.3.4/24" or "1:2::3:4/64") in the input string.  This differs from how some database systems (like postgreSQL) support IP address types, so if you need that sort of functionality when processing 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 netmask

$ipaddr = '1:2::3:4/64'; // IPv6 with /64 netmask



// Strip out the netmask, if there is one.

$cx = strpos($ipaddr, '/');

if ($cx)

{

  $subnet = (int)(substr($ipaddr, $cx+1));

  $ipaddr = substr($ipaddr, 0, $cx);

}

else $subnet = null; // No netmask present



// Convert address to packed format

$addr = inet_pton($ipaddr);



// Let's display it as hexadecimal format

foreach(str_split($addr) as $char) echo str_pad(dechex(ord($char)), 2, '0', STR_PAD_LEFT);

echo "<br />\n";



// Convert the netmask

if (is_integer($subnet))

{

  // Maximum netmask length = same as packed address

  $len = 8*strlen($addr);

  if ($subnet > $len) $subnet = $len;

  

  // Create a hex expression of the subnet mask

  $mask  = str_repeat('f', $subnet>>2);

  switch($subnet & 3)

  {

  case 3: $mask .= 'e'; break;

  case 2: $mask .= 'c'; break;

  case 1: $mask .= '8'; break;

  }

  $mask = str_pad($mask, $len>>2, '0');



  // Packed representation of netmask

  $mask = pack('H*', $mask);

}



// Display the netmask as hexadecimal

foreach(str_split($mask) as $char) echo str_pad(dechex(ord($char)), 2, '0', STR_PAD_LEFT);



?>

eric at vyncke org 18-Jul-2007 10:52


Not so easy in the function below... It is not handling the case of '::' which can happen in an IPv6 and represents any number of 0, addresses could be as simple as ff05::1

me at diogoresende dot net 16-May-2006 02:34


If you want to use the above function you should test for ':' character before '.'. Meaning, you should check if it's an ipv6 address before checking for ipv4.

Why? IPv6 allows this type of notation:



::127.0.0.1



If you check for '.' character you will think this is an ipv4 address and it will fail.