Build if statement from variable string - php

Question

I am wanting to create an if(){} statement from the information specified in a variable.
My current code creates the string from a foreach loop, I am trying to filter out IP addresses in my code from being entered into my database.
Code that creates the string:
//Set excluded IP's
$exclude = "10.1.1.0/24, 192.168.1.0/24";
//Convert excluded to ranges
$ranges = cidrToRange($exclude);
//Build IP address exclusion if statement
$statement = NULL;
foreach($ranges as $ip_ranges) {
$statement .= " !((".ip2long($ip_ranges['start'])." <= $ip_address) && ($ip_dst <= ".ip2long($ip_ranges['end']).")) AND ";
}
//Strip and at end
$statement = rtrim($statement, "AND ");
The $ip_address variable needs to be inserted into the if statement afterwards(later in the script)
The $statement output of this code with the values specified in the $exclude variable will output:
!((167837952 <= $ip_address) && ($ip_address <= 167838207)) AND !((3232235776 <= $ip_address) && ($ip_address <= 3232236031))
I am wanting to use that string in an if statement, so the final result should look like:
if(!((167837952 <= $ip_address) && ($ip_address <= 167838207)) AND !((3232235776 <= $ip_address) && ($ip_address <= 3232236031))) {
//Do this
}
Is this possible to implement into my code?

Answer 1

Building a dynamic if statement is one thing, testing it is another. A simple alternative is to just search through the list and check if the IP address falls into the range. This checks each item and as soon as it matches it will stop and $save will be false.
//Convert excluded to ranges
$ranges = cidrToRange($exclude);
// Check if IP is to be saved -
$save = true;
foreach ( $ranges as $ip_ranges) {
if ( $ip_ranges['start'] <= $ip_address && $ip_address <= $ip_ranges['end'] ) {
$save = false;
break;
}
}
This assumes that $ip_address is also a long and not a string, something like...
$ip_address = ip2long("10.10.0.1");

Answer 2

I have figured out a way to do what I was wanting
My code
//Check if IP address is in a range
function check_ip_range($ip_address, $ip_ranges){
$ip_address = ip2long($ip_address);
foreach($ip_ranges as $ranges) {
if((ip2long($ranges['start']) <= $ip_address && $ip_address <= ip2long($ranges['end']))) {
//echo long2ip($ip_address)." is between ".$ranges['start']." and ".$ranges['end']."<br>";
return(true);
}
}
return(false);
}
I now have my code in my script like this:
//Configure ranges to exclude from accounting
$config['accounting']['exclude'] = "10.0.0.0/8";
//Convert ranges to array start and end
$exclude_ranges = cidrToRange($config['accounting']['exclude']);
//If IP is not in range
if(!check_ip_range($ip_address, $exclude_ranges)) {
//Do this
}