Question

i want to allow users to filter their login based on their ip address (a new settings in the user preferences i will implement).

so if a user with a specific ip login and there is not restriction, the login is successful.

in any other case i was thinking this

if the user choose his full IP like 67.31.85.47 and he has this IP then the login is good
if a user choose 67.31.85.* and has this IP then the login is good
if a user choose 67.31.. and has this IP then the login is good
if a user choose 67...* and has this IP then the login is good
any other case it’s invalid

the user can choose up to 5 IP restrictions. eg:

67.31.*.*
167.77.47.*
62.11.28.28
25.57.*.*
169.*.*.*

i was tinking to strip the IP using explode and then compared to all restrictions he setup.
this can be slow since i have to check 5 times * 4 (4 = IP exploded on the dot)

is there a faster way to do it?
thanks

Answer 1

<?php
function testIP($ip) {
    if($ip == '*' || $ip == '*.*.*.*') {
        return TRUE;
    }
    if($_SERVER['REMOTE_ADDR'] == $ip) {
        return TRUE;
    }
    $mask = str_replace('.*', '', $ip);
    return strpos($_SERVER['REMOTE_ADDR'], $mask) === 0;
}

$_SERVER['REMOTE_ADDR'] = '70.69.68.67';

$ip = '1.11.1.*';
echo "Is $ip good: "; var_dump(testIP($ip));
$ip = '2.34.9.1';
echo "Is $ip good: "; var_dump(testIP($ip));
$ip = '70.11.*.*';
echo "Is $ip good: "; var_dump(testIP($ip));
$ip = '70.69.68.*';
echo "Is $ip good: "; var_dump(testIP($ip));
$ip = '70.69.*.*';
echo "Is $ip good: "; var_dump(testIP($ip));
$ip = '70.*.*.*';
echo "Is $ip good: "; var_dump(testIP($ip));
$ip = '*.*.*.*';
echo "Is $ip good: "; var_dump(testIP($ip));
$ip = '*';
echo "Is $ip good: "; var_dump(testIP($ip));

will output:

Is 1.11.1.* good: bool(false)
Is 2.34.9.1 good: bool(false)
Is 70.11.*.* good: bool(false)
Is 70.69.68.* good: bool(true)
Is 70.69.*.* good: bool(true)
Is 70.*.*.* good: bool(true)
Is *.*.*.* good: bool(true)
Is * good: bool(true)

If you are looking for specific ip (no wild card) checking, you can use:

function is_private_ip($ip) {
  return filter_var($ip, FILTER_VALIDATE_IP) != FALSE;
}

var_dump(is_private_ip(‘82.237.3.3’));
var_dump(is_private_ip(‘748.1234.5.4’));