How to get IP from text area that contains multiple IPs and their CIDR?

Question

matei_ 0 Newbie Poster

4 Years Ago

My question is simple: I have a text area that is filled with IP/CIDR's and I want to know how I can retrieve an IP from there and then check the IP as used.

The text area (which is implemented in plugin's page configuration and I can edit the configuration page through API, I can get the value from the text area using $pluginData -> ipAddresses) I have, is filled with IP/CIDR that are separated by comma, such as: "32.89.178.0/24, 63.119.179.0/24, 23.119.180.0/24,154.119.181.0/24,193.119.182.0/24,133.119.183.0/24".

My question is: how can I retrieve all the IPs that are in that text area and show them on my admin page, aswell as setting them as a attribute to a service for my client? If it used to check it as "used" and cannot longer be used until it is unchecked.

Since I try to find a solution for my problem I just tried to use "cidrToRange" function but the only thing that I get is "Array".

api database-sql php

Edited 4 Years Ago by matei_

5 Contributors
15 Replies
408 Views
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Latest Post 4 Years Ago Latest Post by Josh Connerty

Dani AI

Generated 9 Months Ago

A compact, durable approach that fits the suggestions already in this thread (, , , ) is:

Normalize and split the textarea into individual CIDR entries (handle commas, newlines and stray whitespace).
Convert each CIDR into numeric start/end (two unsigned integers) and store those ranges in the database.
Avoid expanding large CIDR blocks into millions of IP strings — expand only when needed for display or small ranges. Use numeric range checks in SQL to mark/check "used" status atomically.

Example parser (robust splitting + trimming):

$raw = (string) $pluginData->ipAddresses;
$entries = array_values(array_filter(array_map('trim',
    preg_split('/[,\r\n;]+/', $raw)
)));
// $entries now holds each "x.x.x.x/yy"

Example helper to get numeric bounds for a CIDR (returns [start_int, end_int] or false):

function cidr_bounds($cidr) {
    $parts = array_pad(explode('/', $cidr, 2), 2, null);
    if (!filter_var($parts[0], FILTER_VALIDATE_IP, FILTER_FLAG_IPV4) || !is_numeric($parts[1])) {
        return false;
    }
    $prefix = (int)$parts[1];
    $ipLong = (float) sprintf('%u', ip2long($parts[0]));
    $hosts = pow(2, 32 - $prefix);
    $start = floor($ipLong / $hosts) * $hosts;
    $end = $start + $hosts - 1;
    return [(int)$start, (int)$end];
}

Suggested table + queries (store ranges; check membership without expanding):

CREATE TABLE ip_ranges (
  id INT AUTO_INCREMENT PRIMARY KEY,
  client_id INT NOT NULL,
  cidr VARCHAR(32) NOT NULL,
  start_ip INT UNSIGNED NOT NULL,
  end_ip   INT UNSIGNED NOT NULL,
  used TINYINT(1) DEFAULT 0,
  INDEX(client_id),
  INDEX(start_ip),
  INDEX(end_ip)
);

Check if an IP is used (MySQL INET_ATON):

SELECT id FROM ip_ranges
WHERE client_id = ? AND start_ip <= INET_ATON(?) AND end_ip >= INET_ATON(?) AND used = 1 LIMIT 1;

Detect overlap before inserting a new CIDR:

SELECT id FROM ip_ranges
WHERE client_id = ? AND NOT (end_ip < :new_start OR start_ip > :new_end) LIMIT 1;

Notes and cautions:

Avoid expanding big CIDRs (use a threshold, e.g. > 4096 addresses) — expanding /16+ will exhaust memory and UI.
ip2long() can be negative on 32-bit PHP; use sprintf('%u', ip2long(...)) to get unsigned values.
For atomic "mark as used" operations use a transaction or UPDATE ... WHERE used = 0 and check affected rows to prevent race conditions.
IPv6 requires a different strategy (inet_pton, VARBINARY storage or a library).

This ties the split/parse ideas from the thread into a production-friendly workflow: keep ranges in DB, check membership with integer comparisons, and only expand into individual IP strings when safe and necessary.

All 15 Replies

pzuurveen 90 Posting Whiz in Training

4 Years Ago

Why not use explode

Dani 5,664 The Queen of DaniWeb

4 Years Ago

Have you tried using explode()?

function cidrToRange($cidr) {
    $range = array();
    $cidr = explode('/', $cidr);
    $range[0] = long2ip((ip2long($cidr[0])) & ((-1 << (32 - (int)$cidr[1]))));
    $range[1] = long2ip((ip2long($range[0])) + pow(2, (32 - (int)$cidr[1])) - 1);
    return $range;
}
var_dump(cidrToRange("73.35.143.32/27"));

//////////////////OUTPUT////////////////////////
// array(2) {
//   [0]=>
//   string(12) "73.35.143.32"
//   [1]=>
//   string(12) "73.35.143.63"
// }
/////////////////////////////////////////////////

matei_ commented: This function only shows the first and the last IP from the CIDR range. +0

Josh Connerty 20 Unverified User

4 Years Ago

If theres discrepencies with spaces etc. I'd consider

$ips = explode(",",str_replace(" ","",$field)); // Gives IP's
foreach($ips as $key => $ip) {
    $range = explode("/",$ip);
    $ips[$key] = $range;
}

which will strip spaces out and then create an array of ip addresses

[0] => [[0] => 192.168.0.0, [1] => 30]
[1] => [[0] => 192.168.10.0, [1] => 10]

Edited 4 Years Ago by Josh Connerty

matei_ commented: Your function works as you said, but what I am trying to do is to retrieve a full list with IPs from the CIDR ranges that I have. +0

Josh Connerty 20 Unverified User

4 Years Ago

Got meetings for the next couple of hours. I'll post something as soon as I get chance

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This function only shows the first and the last IP from the CIDR range.
Your function works as you said, but what I am trying to do is to retrieve a full list with IPs from the CIDR ranges that I have.

ishu_1 0 Newbie Poster · Answer 1 · 2021-12-20T12:07:44+00:00

<?php
$lines = explode("\n", $instruction_textarea); 
if ( !empty($lines) ) 
  echo '<ul>';
  foreach ( $lines as $line ) 

    echo '<li>'. trim( $line ) .'</li>';


  echo '</ul>';

?>

matei_ 0 Newbie Poster · Answer 2 · 2021-12-21T09:07:48+00:00

I found a solution that shows me the list of IPs from the first CIDR range. This is the function that I use:

function cidrToRange($cidr) {
    $range = array();
    $split = explode('/', $cidr);

    if(!empty($split[0]) && is_scalar($split[1]) && filter_var($split[0], FILTER_VALIDATE_IP, FILTER_FLAG_IPV4)) {
        $rangeStart = ip2long($split[0]) & ((-1 << (32 - (int) $split[1])));
        $rangeStartIP = long2ip($rangeStart);
        $rangeEnd = ip2long($rangeStartIP) + pow(2, (32 - (int) $split[1])) - 1;

        for($i = $rangeStart; $i <= $rangeEnd; $i ++) {
            $range[] = long2ip($i);
        }
        return $range;
    } else {
        return $cidr;
    }
}

$IPs = cidrToRange($pluginData -> ipAddresses);

foreach($IPs as $IP) {
    echo "$IP\n";
}

But I want to show a list with all the IPs from all the CIDR ranges.

Josh Connerty 20 Unverified User · Answer 3 · 2021-12-21T09:44:13+00:00

function cidrToRange($cidr) {
    $range = array();
    $split = explode('/', $cidr);

    if(!empty($split[0]) && is_scalar($split[1]) && filter_var($split[0], FILTER_VALIDATE_IP, FILTER_FLAG_IPV4)) {
        $rangeStart = ip2long($split[0]) & ((-1 << (32 - (int) $split[1])));
        $rangeStartIP = long2ip($rangeStart);
        $rangeEnd = ip2long($rangeStartIP) + pow(2, (32 - (int) $split[1])) - 1;

        for($i = $rangeStart; $i <= $rangeEnd; $i ++) {
            $range[] = long2ip($i);
        }
        return $range;
    } else {
        return $cidr;
    }
}

$ip_arr = array();

foreach($cidrs as $cidr)
{
    array_merge(cidrToRange($cidr),$ip_arr);
}
echo '<ul>';
foreach($ip_arr as $ip)
{
    echo '<li>'.$ip.'</li>';
}
echo '</ul>';

"Notice: Undefined variable: cidrs on line 41 && Warning: Invalid argument supplied for" - Line 41" foreach($cidrs as $cidr)

Josh Connerty 20 Unverified User · Answer 4 · 2021-12-21T10:23:34+00:00

Josh Connerty 20 Unverified User

4 Years Ago

$cidrs is not defined yet. This would be for instance explode(",",$my_form_field) passing an array of ranges

matei_ commented: I get only the CIDR, e.g.: 88.39.88.0/24, 89.33.88.0/24 etc.. I want to retrieve a list with IPs from all the CIDRs that I have in my textarea. +0

Josh Connerty 20 Unverified User · Answer 5 · 2021-12-21T10:40:01+00:00

Give me an 20 mins and I'll write something for you. Just got to finish what I'm on and push to live

Josh Connerty 20 Unverified User · Answer 6 · 2021-12-21T11:08:53+00:00

Something like that

<?php

    $ip_ranges = "32.89.178.30/24, 63.119.179.0/24, 23.119.180.0/24,154.119.181.0/24,193.119.182.0/24,133.119.183.0/24";
    function multiCidrToRange($cidrs)
    {
        $return_array = array();
        $cidrs = explode(",",str_replace(" ","",$cidrs));
        foreach($cidrs as $cidr)
        {
            $begin_end = explode("/",$cidr);
            $ip_exp = explode(".",$begin_end[0]);
            $range[] = $begin_end[1];
            $range[] = $ip_exp[3];
            unset($ip_exp[3]);
            $ip_prefix = implode(".",$ip_exp);
            $count = $range[1];
            while( $count <= ($range[0] + $range[1]) )
            {
                $return_array[] = $ip_prefix . "." . $count;
                if($count == 255)
                { exit; }
                $count++;
            }
            $begin_end = false;
            $ip_exp = false;
            $range = false;
            $ip_prefix = false;
            $count = false;
        }
        return $return_array;
    }

    var_dump(multiCidrToRange($ip_ranges));

?>

Using "var_dump($pluginData -> ipAddresses)" it shows me this: "array(0) { }"...

Josh Connerty 20 Unverified User · Answer 7 · 2021-12-22T10:04:34+00:00

What does $pluginData hold? if you pass a list of comma separated range values to the function it will return an array of ip addresses from all of the ranges

The $pluginData -> ipAddresses is the actual text area that holds all the CIDR ranges.

Josh Connerty 20 Unverified User · Answer 8 · 2021-12-22T10:07:49+00:00

So if you var_dump the text field and it's an empty array it implies it has nothing in the textfield. I need to see more of how it's implemented

I solved the error, but the problem is now that I get only the IPs only to .24 and I should get until .255

Josh Connerty 20 Unverified User · Answer 9 · 2021-12-22T10:28:55+00:00

Josh Connerty 20 Unverified User

4 Years Ago

OH I see. That won't work then. Let me look up the calculations for the range

matei_ commented: Any updates? Can't we work something from cidrToRange function? +0

Josh Connerty 20 Unverified User · Answer 10 · 2021-12-22T12:53:34+00:00

I tested this while in a meeting so fingers crossed it works for you:

<?php

$ip_ranges = "63.119.179.0/24, 23.119.180.0/24,154.119.181.0/24,193.119.182.0/24,133.119.183.0/24";
    function multiCidrToRange($cidrs)
    {
        $return_array = array();
        $cidrs = explode(",",str_replace(" ","",$cidrs));
        foreach($cidrs as $cidr)
        {
            $begin_end = explode("/",$cidr);
            $ip_exp = explode(".",$begin_end[0]);
            $range[0] = long2ip((ip2long($begin_end[0])) & ((-1 << (32 - (int)$begin_end[1]))));
            $range[1] = long2ip((ip2long($range[0])) + pow(2, (32 - (int)$begin_end[1])) - 1);
            unset($ip_exp[3]);
            $ip_prefix = implode(".",$ip_exp);
            $count = str_replace($ip_prefix . ".","",$range[0]);
            $ncount = 0;
            while( $count <= (str_replace($ip_prefix,"",$range[0]) + str_replace($ip_prefix . ".","",$range[1])) )
            {
                $return_array[] = $ip_prefix . "." . $count;
                $count++;
                $ncount++;
            }
            $begin_end = false;
            $ip_exp = false;
            $range = false;
            $ip_prefix = false;
            $count = false;
        }
        return $return_array;
    }

    var_dump(multiCidrToRange($ip_ranges));

?>

Thank you very much! You saved me. It works in the way I want it to.

Josh Connerty 20 Unverified User · Answer 11 · 2021-12-23T20:14:22+00:00

Josh Connerty 20 Unverified User

4 Years Ago

Glad to hear it :)

How to get IP from text area that contains multiple IPs and their CIDR?

Dani AI

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