inet_ntop
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.
inet_pton
(PHP 5 >= 5.1.0)
inet_pton — Converts a human readable IP address to its packed in_addr representation
Description
string inet_pton
( string
$address
)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.
Parameters
-
address -
A human readable IPv4 or IPv6 address.
Return Values
Returns the in_addr representation of the given
address, or FALSE if a syntactically invalid
address is given (for example, an IPv4 address
without dots or an IPv6 address without colons).
Examples
Example #1 inet_pton() Example
<?php
$in_addr = inet_pton('127.0.0.1');
$in6_addr = inet_pton('::1');
?>
Changelog
| Version | Description |
|---|---|
| 5.3.0 | This function is now available on Windows platforms. |
See Also
- ip2long() - Converts a string containing an (IPv4) Internet Protocol dotted address into a proper address
- long2ip() - Converts an (IPv4) Internet network address into a string in Internet standard dotted format
- inet_ntop() - Converts a packed internet address to a human readable representation
add a note
User Contributed Notes
inet_pton - [6 notes]
me at diogoresende dot net ¶
7 years ago
eric at vyncke org ¶
5 years ago
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
francis dot besset at gmail dot com ¶
1 year ago
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 ¶
3 years ago
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);
?>
djmaze(AT)dragonflycms(.)org ¶
7 years ago
If you need the functionality but your PHP version doesn't have the functionality (like on windows) the following might help
<?php
function inet_pton($ip)
{
# ipv4
if (strpos($ip, '.') !== FALSE) {
$ip = pack('N',ip2long($ip));
}
# ipv6
elseif (strpos($ip, ':') !== FALSE) {
$ip = explode(':', $ip);
$res = str_pad('', (4*(8-count($ip))), '0000', STR_PAD_LEFT);
foreach ($ip as $seg) {
$res .= str_pad($seg, 4, '0', STR_PAD_LEFT);
}
$ip = pack('H'.strlen($res), $res);
}
return $ip;
}
?>
SK at example dot com ¶
10 months ago
I noticed that inet_pton() doesn't like compressed single hex groups
i.e. ::ffff:ffff:ffff:ffff:ffff:ffff:ffff and ::ffff:ffff:ffff:ffff:ffff:127.0.0.1
work around and/or PHP 4.0.1+ add-in:
<?php
function ip2bin($ip)
{
$s = $ipv4 = '';
if(strpos($ip, ':') !== false)
{
if(!($l = preg_match_all('#(?|::|(?|\d{1,3}\.){3}\d{1,3}|[0-9a-f]{1,4})#i', $ip, $m)) || $l > 8)
return false;
foreach($m[0] as $p)
{
if($p == '::')
$s .= str_repeat('0000', 8 - $l + (strpos($m[0][$l-1], '.') === false));
else if(strpos($p, '.') !== false)
$ipv4 = ip2bin($p);
else
$s .= str_pad($p, 4, '0', STR_PAD_LEFT);
}
if($ipv4 === false)
return false;
return pack('H*', $s). $ipv4;
}
else if(strpos($ip, '.') !== false)
{
$x = explode('.', $ip);
if(count($x) != 4)
return false;
foreach($x as $i)
$s .= chr((int) $i);
return $s;
}
return false;
}
var_dump(
@inet_pton('::ffff:ffff:ffff:ffff:ffff:ffff:ffff'), // bool(false)
ip2bin('::ffff:ffff:ffff:ffff:ffff:ffff:ffff'),
@inet_pton('::ffff:ffff:ffff:ffff:ffff:127.0.0.1'), // bool(false)
ip2bin('::ffff:ffff:ffff:ffff:ffff:127.0.0.1')
);
?>