?
Solved

Matching IP number with preset networks

Posted on 2002-06-10
6
Medium Priority
?
244 Views
Last Modified: 2006-11-17
What I need is to check if the given IP number is
from one of the networks supplied in an array like
$a[]=array('195.250.64.0', '0.0.31.255');
$a[]=array('212.73.64.0', '0.0.31.255');
$a[]=array('212.42.192.0', '0.0.31.255');
etc, where the second field is netmask. the function
should return true or false.

Anyone ever coded such thing?
0
Comment
Question by:Vahan Yerkanian
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 3
  • 2
6 Comments
 
LVL 32

Expert Comment

by:Batalf
ID: 7066438
What kind of netmask is that? is it opposite of what's normal. Normally "1" determines host/server, when "0" determines client addresses.
 
0
 
LVL 1

Author Comment

by:Vahan Yerkanian
ID: 7066453
It's a reverse netmask. The problem is that I'm not so good with the netmask calculation, that's why I posted the question :0 The netmasks in above mean that each 31.255 should cover 32 C class networks.
0
 
LVL 40

Expert Comment

by:Richard Quadling
ID: 7066522
This is off the top of my head, but why not turn the IP address into a 32 bit integer and the mask into the range.

So.

195.250.64.0 = (((((195 * 256) + 250) * 256) + 64) * 256) + 0 = 3287957504

And the mask of 0.0.31.255, is 31 * 256 + 255 = 8191.

So, you can now check to see if the address is between 3287957504 and 3287965695.

You can split the IP address into bits by using

$a = preg_split("(\d{1,3}).(\d{1,3}).(\d{1,3}).(\d{1,3})",$IP_address);

And then you can use $a[0] .. $a[3].

Hope this helps a bit.

Richard Quadling.
0
VIDEO: THE CONCERTO CLOUD FOR HEALTHCARE

Modern healthcare requires a modern cloud. View this brief video to understand how the Concerto Cloud for Healthcare can help your organization.

 
LVL 1

Author Comment

by:Vahan Yerkanian
ID: 7066575
Can u post a working code here? 150 points is not enough?
0
 
LVL 40

Accepted Solution

by:
Richard Quadling earned 600 total points
ID: 7066610
Hopefully this will show you what I mean.

<?php

$aValidIPs['212.73.64.0'] = '0.0.31.255';
$aValidIPs['212.42.192.0'] = '0.0.31.255';
$aValidIPs['195.250.64.0'] = '0.0.31.255';

$YourIPtoTest = '195.250.92.24';

function GetInt($sGI)
{
echo "DEBUG : Checking $sGI<br>";
$a = explode('.',$sGI,4);
echo "DEBUG : Array is $a[0] - $a[1] - $a[2] - $a[3]<br>";
echo "DEBUG : Value is " . (((((($a[0] * 256) + $a[1]) * 256) + $a[2]) * 256) + $a[3]) . "<br>";
return (((((($a[0] * 256) + $a[1]) * 256) + $a[2]) * 256) + $a[3]);
}

function CheckIP($aCIP,$IP)
{
foreach($aCIP as $BaseIP => $Range)
 {
 $FirstIPVal = GetInt($BaseIP);
 $LastIPVal = $FirstIPVal + GetInt($Range);
 $IPVal = GetInt($IP);
 echo "DEBUG : FirstIP $FirstIPVal - LastIP $LastIPVal - IP $IPVal<br>";
 if (($IPVal >= $FirstIPVal) and ($IPVal <= $LastIPVal))
  {
  return true;
  }
 }
return false;
}

if (CheckIP($aValidIPs,$YourIPtoTest) == true)
 {
 echo 'Valid';
 }
else
 {
 echo 'Invalid';
 }

?>

Regards,

Richard.
0
 
LVL 1

Author Comment

by:Vahan Yerkanian
ID: 7066709
"Works as advertised" :0

Thanks Richard!
0

Featured Post

Video: Liquid Web Managed WordPress Comparisons

If you run run a WordPress, you understand the potential headaches you may face when updating your plugins and themes. Do you choose to update on the fly and risk taking down your site; or do you set up a staging, keep it in sync with your live site and use that to test updates?

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

These days socially coordinated efforts have turned into a critical requirement for enterprises.
3 proven steps to speed up Magento powered sites. The article focus is on optimizing time to first byte (TTFB), full page caching and configuring server for optimal performance.
Explain concepts important to validation of email addresses with regular expressions. Applies to most languages/tools that uses regular expressions. Consider email address RFCs: Look at HTML5 form input element (with type=email) regex pattern: T…
The viewer will learn how to count occurrences of each item in an array.
Suggested Courses

762 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question