判断IP是否属于某个网段

ipInNetwork.php

<?php

function ipInNetwork($ip, $network) {
    if(!filter_var($ip, FILTER_VALIDATE_IP)) {
        throw new \Exception($ip . '不是有效IP地址');
    }
    if(!preg_match('/\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\/\d+/', $network)) {
        throw new \Exception($network . '不是有效网段设置，如：192.168.0.1/24');
    }

    $s = explode('/', $network);
    $ipBin = decbin(ip2long($s[0]));

    if(32 < $s[1]) {
        throw new \Exception('网段掩码位必须为0-32');
    }

    $maskBin = str_repeat('1', $s[1]).str_repeat('0', 32 - $s[1]);
    $ipNet = ($ipBin & $maskBin);

    $ipBin = decbin(ip2long($ip));
    $cipNet = ($ipBin & $maskBin);

    return $ipNet == $cipNet;
}