ip-restrictor/src/isInternalIP.js

Easily allow or block internal IPs in Node.js and Express apps. A simple middleware for IP filtering and network security.

const isInternalIP = (ip) => {
    return /^((10\.)|(192\.168\.)|(172\.(1[6-9]|2[0-9]|3[0-1])))/.test(ip);
};

module.exports = isInternalIP;