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ip2long

sealbreaker at email dot com
03-Nov-2007 01:47


As a note : if you are using (PHP 4, PHP 5) and are looking to get the integer value of an IP address, i have found that the following works flawlessly for converting to and from IPv4 and it's integer equivalent. I must give credit elsewhere for this portion of the code (ip2long($ip) & 0x7FFFFFFF) + 0x80000000). I looked but was unable to find the comment where it was included.



$ip = "127.0.0.0"; // as an example



$integer_ip = (substr($ip, 0, 3) > 127) ? ((ip2long($ip) & 0x7FFFFFFF) + 0x80000000) : ip2long($ip);



echo $integer_ip; // integer value of IP address

echo long2ip($integer_ip); // convert to an IPv4 formatted address

-----------------------

Results are as follows:

-----------------------

2130706432

127.0.0.0

-----------------------

255.255.255.255 (converts to) 4294967295 (and back to) 255.255.255.255

209.65.0.0 (converts to) 3510697984 (and back to) 209.65.0.0

12.0.0.0 (converts to) 201326592 (and back to) 12.0.0.0

1.0.0.0 (converts to) 16777216 (and back to) 1.0.0.0

ir on ir id is at gm ai ld ot co m
20-Oct-2007 11:54


Keep in mind that storing IP addresses inside of your database as integers (rather than 15 character strings in decimal format, or 8 character strings in hex format) is hundreds of times faster.



Take the typical case of a MySQL database doing a search for an IP address on thousands (or millions!) of rows; you're either doing a string compare for each entry, or an integer equation. If you do your indexes correctly, your lookups should be literally 100x faster using an INT rather than a VARCHAR.



Also note that an integer doesn't need to be escaped when passed to a database. :)

andrew dot minerd at sellingsource dot com
20-Jul-2007 05:15


A somewhat more efficient alternative to convert the signed integer return by ip2long:



$float = ((ip2long($ip) & 0x7FFFFFFF) + 0x80000000);

one tiger one at gee mail dot comm
02-Apr-2007 07:49


I wrote a small function to validate a netmask (We have a form where the netmask of a given server is entered in, and I wanted to make sure it was valid). Hope this is useful.



// Netmask Validator //

function checkNetmask($ip) {

 if (!ip2long($ip)) {

  return false;

 } elseif(strlen(decbin(ip2long($ip))) != 32 && ip2long($ip) != 0) {

  return false;

 } elseif(ereg('01',decbin(ip2long($ip))) || !ereg('0',decbin(ip2long($ip)))) {

  return false;

 } else {

  return true;

 }

}

laacz at php dot net
16-Feb-2007 01:06


Just to save you some time.



Beware that octets in IP address are being treated as numbers. So, '10.0.0.11' is not equal to '10.0.0.011'. '011' is octal number (base 8), so it converts to '9'. You can even go further and see that '10.0.0.0xa' also works (equals to '10.0.0.16'). 



This is not PHP issue, though.

samb057 at gmail dot com
26-Dec-2006 12:37


Convert an ipv6 address to an base 10 integer



function ip2long6($ip)

    {

        if (substr_count($ip, '::'))

            {

                $ip = str_replace('::', str_repeat(':0000', 8 - substr_count($ip, ':')) . ':', $ip) ;

            }

            

        $ip = explode(':', $ip) ;

        

        $r_ip = '' ;

        foreach ($ip as $v)

            {

                $r_ip .= str_pad(base_convert($v, 16, 2), 16, 0, STR_PAD_LEFT) ;

            }

            

        return base_convert($r_ip, 2, 10) ;

    }

samb057 at gmail dot com
26-Dec-2006 12:20


Here's a simple IP address match checking function.



It takes 3 arguments: ip address to check (after ip2long), ip address to check against (after ip2long), and mask to check against (integer 0-32).



Just make sure you perform ip2long on the ip addresses before inputting them to the function.



function match_ip($check_ip, $match_ip, $match_mask = 32)

    {

        for ($i = 0 ; $i < $match_mask ; $i++)

            {

                $n = pow(2, 31 - $i) ;

                if (($n & $check_ip) != ($n & $match_ip))

                    {

                        return FALSE ;

                    }

            }

            

        return TRUE ;

    }

    

I've been looking for a function like this for a while, i hope it helps someone.

Ian B
24-Dec-2006 04:22


NOTE: ip2long() should NOT be used for CIDR calculation. 

Instead, you should use something like the following:



<?php

        /* get the base and the bits from the ban in the database */

        list($base, $bits) = explode('/', $CIDR);



        /* now split it up into it's classes */

        list($a, $b, $c, $d) = explode('.', $base);



        /* now do some bit shfiting/switching to convert to ints */

        $i = ($a << 24) + ($b << 16) + ($c << 8) + $d;

        $mask = $bits == 0 ? 0 : (~0 << (32 - $bits));



        /* here's our lowest int */

        $low = $i & $mask;



        /* here's our highest int */

        $high = $i | (~$mask & 0xFFFFFFFF);



        /* now split the ip were checking against up into classes */

        list($a, $b, $c, $d) = explode('.', $iptocheck);



        /* now convert the ip we're checking against to an int */

        $check = ($a << 24) + ($b << 16) + ($c << 8) + $d;



        /* if the ip is within the range, including 

      highest/lowest values, then it's witin the CIDR range */

        if ($check >= $low && $check <= $high)

            return 1;

       else

            return 0;

?>



This means that you should check to see if the IP

address is of the correct format each time.

jgwright
25-Oct-2006 12:13


Here is a modified version of the code posted by legetz81 (AT) yahoo (dot) com. It handles the shorter, and more common, notation: "189.128/11".



<?php



$ip_addr_cidr = "192.168.37.215/27";

cidr($ip_addr_cidr);



function cidr($ip_addr_cidr) {



$ip_arr = explode('/', $ip_addr_cidr);



$dotcount = substr_count($ip_arr[0], ".");

$padding = str_repeat(".0", 3 - $dotcount);

$ip_arr[0].=$padding;



$bin = '';

for($i=1;$i<=32;$i++) {

   $bin .= $ip_arr[1] >= $i ? '1' : '0';

}

$ip_arr[1] = bindec($bin);



$ip = ip2long($ip_arr[0]);

$nm = ip2long($ip_arr[1]);

$nw = ($ip & $nm);

$bc = $nw | (~$nm);



echo "Number of Hosts:    " . ($bc - $nw - 1) . "\n";

echo "Host Range:        " . long2ip($nw + 1) . " -> " . long2ip($bc - 1)  . "\n";



/*

This will produce:

Number of Hosts:    30

Host Range:        192.168.37.193 -> 192.168.37.222

*/



}



?>

dh06 at biztechwiz dot com
24-Oct-2006 09:59


I made one tiny change to Stephane's routine below when I had problems with spaces in an IP range.  I moved the trim function before the ip2long call.



Thanks Stephane!



Dirk.



<?php

function netMatch($network, $ip) {



   $network=trim($network);

   $ip = trim($ip);



   $d = strpos($network,"-");

   if ($d===false) {

       $ip_arr = explode('/', $network);

  

       if (!preg_match("@\d*\.\d*\.\d*\.\d*@",$ip_arr[0],$matches)){

           $ip_arr[0].=".0";    // Alternate form 194.1.4/24

       }



       $network_long = ip2long($ip_arr[0]);

       $x = ip2long($ip_arr[1]);

          

       $mask = long2ip($x) == $ip_arr[1] ? $x : (0xffffffff << (32 - $ip_arr[1]));

       $ip_long = ip2long($ip);

  

       return ($ip_long & $mask) == ($network_long & $mask);

   }

   else {

       $from = ip2long(trim(substr($network,0,$d)));

       $to = ip2long(trim(substr($network,$d+1)));



       $ip = ip2long($ip);

       return ($ip>=$from and $ip<=$to);

   }

}

?>

stephane at deluca dot biz
01-Oct-2006 01:40


I propose a new function to match an IP against a network.

You can define the network in two different manner, most suited for handling data grabed from WHOIS records:

- 202.1.192.0-202.1.192.255: a range of IPs

- 200.36.161.0/24: a range of IP by using net masking

- 200.36.161/24: a shorten syntax similar to the above.



Sdl



<?php

function netMatch($network, $ip) {



    $network=trim($network);

    $ip = trim($ip);



    $d = strpos($network,"-");

    if ($d===false) {

        $ip_arr = explode('/', $network);

    

        if (!preg_match("@\d*\.\d*\.\d*\.\d*@",$ip_arr[0],$matches)){

            $ip_arr[0].=".0";    // Alternate form 194.1.4/24

        }



        $network_long = ip2long($ip_arr[0]);

        $x = ip2long($ip_arr[1]);

            

        $mask = long2ip($x) == $ip_arr[1] ? $x : (0xffffffff << (32 - $ip_arr[1]));

        $ip_long = ip2long($ip);

    

        return ($ip_long & $mask) == ($network_long & $mask);

    }

    else {

        $from = trim(ip2long(substr($network,0,$d)));

        $to = trim(ip2long(substr($network,$d+1)));



        $ip = ip2long($ip);

        return ($ip>=$from and $ip<=$to);

    }

}

?>

legetz81 (AT) yahoo (dot) com
30-Mar-2006 06:15


Here is a script that will calculate host range and number of hosts with a given ip address CIDR notation (modified code which was posted by phl AT cyways.com):



$ip_addr_cidr = "192.168.37.215/27";

$ip_arr = explode('/', $ip_addr_cidr);



$bin = '';

for($i=1;$i<=32;$i++) {

    $bin .= $ip_arr[1] >= $i ? '1' : '0';

}

$ip_arr[1] = bindec($bin);



$ip = ip2long($ip_arr[0]);

$nm = ip2long($ip_arr[1]);

$nw = ($ip & $nm);

$bc = $nw | (~$nm);



echo "Number of Hosts:    " . ($bc - $nw - 1) . "\n";

echo "Host Range:         " . long2ip($nw + 1) . " -> " . long2ip($bc - 1)  . "\n";



This will produce:

Number of Hosts:    30

Host Range:         192.168.37.193 -> 192.168.37.222

Polarina
10-Mar-2006 06:37


Using the option that "paul at santasoft point com" mentioned will make IP Addresses larger than 2147483647 (Around 128.0.0.0) become 2147483647 and it wont go higher than that.

So it's not recommended to use his solution.

novikov at harizma dot lv
21-Dec-2005 07:57


Please not , that the results of ip2long on 64bit servers is different form 32bit. 



Take a look here: http://bugs.php.net/bug.php?id=18816



It's a feature, that ip2long on 64bit always returned UNSIGNED result like after spitf("%u\n",ip2long());

greg at netops dot gvtc dot com
19-Dec-2005 03:43


Re:  m.ozarek's isIpMask() function



You might want to adjust your preg_match line from:

 

if(preg_match("/[0-9].[0-9].[0-9].[0-9]/",$mask)){



to



if(preg_match("/[0-9]++\.[0-9]++\.[0-9]++\.[0-9]++/",$mask)){



this should properly match up to 3 characters per octet and require that the periods be periods not just any character.  I tested against a handful of IPs, and it seemed to match fine, and did not allow a 7 digit number to be considered a mask to check.  This is probably more useful if doing a match against a regular IP than against the subnet mask, but its always good to have more layers of checking.



*note.. not all applications support the regex + metacharacter.

paul at santasoft point com
02-Nov-2005 07:03


to complement daevid at daevid dot com's note (11 Nov 2004) about the catch being that PHP returns negative values....



If you define your mysql column that stores the ip address in INT format as signed (not unsigned), then it'll work just fine.  



No need to do any conversion using sprintf and this way you'll keep the value and be able to use PHP's long2ip() function on the value and get an accurate result.



SO..  define your MySQL column as signed (leave the Attributes select box in phpMyAdmin blank) and you won't need to do any conversions or whatnot.

01-Sep-2005 12:47


# m.ozarek

#

# Check if given mask is correct. You can check the short format mask 

# like 8,16,24 or long format like 255.255.255.0 

#



function isIpMask($mask){

    

    $format = '';

    if(preg_match("/[0-9].[0-9].[0-9].[0-9]/",$mask)){

        $format = "long";

    }else{

        if($mask<=30){

            $format = "short";

        }else{

            return false;

        }

    }

    switch($format){

        case long;

            $mask = decbin(ip2long($mask));

        break;

        case short:

            $tmp = $mask;

            for($i=0; $i < $mask ;$i++){

                $tmp.= 1;

            }

            for($j=0; $j < (32 - $mask);$j++){

                $tmp.= 0;

            }

            $mask = $tmp;

        break;

    }

    if(strlen($mask) <= 32){

        for($i=0;$i<=32 ;$i++){

            $bit = substr($mask,$i,1);

            if(($bit - substr($mask,$i+1,1)) < 0){

                return false;

            }

        }

    }

    return true;

}

# EXAMPLE

# isIpMask("255.255.255.0") -> return true

# isIpMask("24") -> return true

# isIpMask("5.5.5.5") -> return false

ken at expitrans dot com
31-Aug-2005 03:31


Below is a merged form of all various notes, and a better (and correct) network matching function.



<?php



function net_match($network, $ip) {

      // determines if a network in the form of 192.168.17.1/16 or

      // 127.0.0.1/255.255.255.255 or 10.0.0.1 matches a given ip

      $ip_arr = explode('/', $network);

      $network_long = ip2long($ip_arr[0]);



      $x = ip2long($ip_arr[1]);

      $mask =  long2ip($x) == $ip_arr[1] ? $x : 0xffffffff << (32 - $ip_arr[1]);

      $ip_long = ip2long($ip);



      // echo ">".$ip_arr[1]."> ".decbin($mask)."\n";

      return ($ip_long & $mask) == ($network_long & $mask);

}



echo net_match('192.168.17.1/16', '192.168.15.1')."\n"; // returns true

echo net_match('127.0.0.1/255.255.255.255', '127.0.0.2')."\n"; // returns false

echo net_match('10.0.0.1', '10.0.0.1')."\n"; // returns true



?>

tristram at ccteam dot ru
26-Jul-2005 06:33


<?php

if (!function_exists("ip2long"))

{

function ip2long($ip)

{

 $ip = explode(".",$ip);

 if (!is_numeric(join(NULL,$ip)) or count($ip) != 4) {return false;}

 else {return $ip[3]+256*$ip[2]+256*256*$ip[1]+256*256*256*$ip[0];}

}

}

?>

cam at wecreate dot com
20-Jul-2005 09:37


A simple function to compare two IP addresses against a netmask. Useful if you're locking down a web app with an IP address, but can't force the IPs to be exactly the same.



function ipcompare ($ip1, $ip2, $mask) {

    $masked1 = ip2long($ip1) & ip2long($mask); // bitwise AND of $ip1 with the mask

    $masked2 = ip2long($ip2) & ip2long($mask); // bitwise AND of $ip2 with the mask

      if ($masked1 == $masked2) return true;

      else return false;

}



Examples:

ipcompare("192.168.1.63","192.168.1.65","255.255.255.0") // true

ipcompare("192.168.1.63","192.168.1.65","255.255.255.192") // false

Paragina Silviu
12-Jul-2005 08:41


Note: ip2long and long2ip do not function as the c linux functions inet_addr and inet_ntoa. They store the long in reverse byte order (little endian vs big endian i guess). 

For example you send 10.0.0.1 to inet_ntoa you take the long from the result and you pass it to long2ip  you get 1.0.0.10. You won't run into this issue unless you use a database both from c linux programs and php scripts.



My first ideea was to reverse the long, but unfortunatley the long was stored as unsigned and i got a lot of problems doing calculations with it (some operations would work well others not; probably it was stored as float i do not know for sure...)



So my solution was



function str_rev_ip($str)

{

    $ar=explode(".",$str);

    return "$ar[3].$ar[2].$ar[1].$ar[0]";

}



and i take the result from inet_ntoa and parse it as str_rev_ip(long2ip($var))

tomlove at gmail dot com
03-Jul-2005 04:09


A quick and efficient way to compare two IPs with a given mask:



<?

function ipmatch ($ip1, $ip2, $mask) {

  if ((ip2long($ip1) & ~(pow(2, 32-$mask)-1)) == (ip2long($ip2) & ~(pow(2, 32-$mask)-1))) return true; 

  else return false;

}

?>



Here's an application of it that selects the best IP given the choice of a (possibly private or invalid) forwarded address or a (possibly proxy) apparent address:



<?

$a = $_SERVER['HTTP_X_FORWARDED_FOR'];

if ($a == '' || ipmatch($a, "10.0.0.0", 8) || ipmatch($a, "172.16.0.0", 12) || ipmatch($a, "192.168.0.0", 16) || ipmatch($a, "255.255.255.255", 32)) $ip = $_SERVER['REMOTE_ADDR'];

else $ip = $a;

?>



Or use it to ban people:



<?

$banned_ip = '135.23.12.3';

if (ipmatch($ip, $banned_ip, 32)) die('BANNED!');

?>



The bitwise comparison the function uses can be done in SQL to do ban matches right in your database.

lawpoop at gmail dot com
06-Apr-2005 03:29


Here is a function that tells you if an ip address is in a CIDR range. However, the CIDR argument can be an array of CIDRs. This was created from other matchCIDR functions in the user notes.



function matchCIDR($addr, $cidr) {



        // $addr should be an ip address in the format '0.0.0.0'

        // $cidr should be a string in the format '100/8'

        //      or an array where each element is in the above format



        $output = false;



        if ( is_array($cidr) ) {



                foreach ( $cidr as $cidrlet ) {

                        if ( matchCIDR( $addr, $cidrlet) ) {

                                $output = true;

                        }

                }



        } else {



                list($ip, $mask) = explode('/', $cidr);



                $mask = 0xffffffff << (32 - $mask);



                $output = ((ip2long($addr) & $mask) == (ip2long($ip) & $mask));



        }



        return $output;

}

mailNO at SPAMdapuzz dot com
13-Feb-2005 11:05


a little function to make a range in this form:

0.0.0.1/0.0.0.255          ==> 0.0.0.1/255

0.0.0.1/255.255.255.255    ==> 0.0.0.1/255.255.255.255



<?php

$primo = "62.4.32.0";

$ultimo = "62.4.63.255";

echo do_range($primo,$ultimo); //Example



function do_range($primo,$ultimo) {

list($a,$b,$c,$d)=explode(".",$primo);

list($e,$f,$g,$h)=explode(".",$ultimo);

if ($a !== $e) return "$primo/$ultimo";

else {

    if ($b !== $f) return "$primo/$f.$g.$h";

    else{

        if ($c !== $g) return "$primo/$g.$h";

        else {

            if ($d !== $h) return "$primo/$h";

            else return -1; //error

            }

        }

    }

}

?>

Please write me if you have any suggestion

frank at vista dot com
26-Jan-2005 05:43


remixing mediator's function further:

<?php

function matchCIDR($addr, $cidr) {

ip2long

Description