Node.js实现的端口扫描器 scan-port

package.json

{
  "name": "scan-port",
  "version": "1.0.0",
  "description": "端口扫描器",
  "main": "scan.js",
  "dependencies": {
    "cli-color": "^1.2.0",
    "progress": "^1.1.8",
    "yargs": "^7.0.2"
  },
  "devDependencies": {},
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "keywords": [
    "scan",
    "port",
    "hack",
    "tool"
  ],
  "author": "Zongmin Lei <leizongmin@gmail.com>",
  "license": "MIT"
}

scan.js

/**
 * 端口扫描器
 *
 * @author Zongmin Lei <leizongmin@gmail.com>
 */

const net = require('net');
const dns = require('dns');
const assert = require('assert');
const argv = require('yargs').argv;
const ProgressBar = require('progress');
const clc = require('cli-color');

// IP地址正则表达式
const REGEXP_IP = /((?:(?:25[0-5]|2[0-4]\d|((1\d{2})|([1-9]?\d)))\.){3}(?:25[0-5]|2[0-4]\d|((1\d{2})|([1-9]?\d))))/;
// 端口范围正则表达式
const REGEXP_PORT_RANGE = /^(\d+)\-(\d+)$/;

/**
 * 判断是否为IP地址
 *
 * @param {String} host
 * @return {Boolean}
 */
function isIPAddress(host) {
  return REGEXP_IP.test(host);
}

/**
 * 解析域名
 *
 * @param {String} domain
 * @return {String}
 */
function resolveDNS(domain) {
  return new Promise((resolve, reject) => {
    dns.resolve4(domain, (err, addresses) => {
      if (err) {
        return reject(err);
      }
      resolve(addresses[0]);
    });
  });
}

/**
 * 检查端口状态
 *
 * @param {String} host
 * @param {Number} port
 * @return {Boolean}
 */
function checkPortStatus(host, port) {
  return new Promise((resolve, reject) => {
    port = Number(port);
    assert(isIPAddress(host), `invalid IP address: ${ host }`);
    assert(port >= 0 && port < 65536, `invalid port: ${ port }`);

    // 尝试连接指定端口，如果连接成功则表示端口开放，并立即销毁连接
    const c = net.connect(port, host);
    let status = false;
    c.on('connect', () => {
      status = true;
      c.destroy()
    });
    c.on('error', err => {
      status = false;
      c.destroy();
    });
    c.on('close', () => {
      c.destroy();
      resolve(status);
    });
  });
}

/**
 * 检查端口范围
 *
 * @param {String} host
 * @param {Number} portStart
 * @param {Number} portEnd
 */
async function checkPortRange(host, portStart, portEnd) {
  console.log('IP: %s', host);
  console.log('Port: %s to %s', portStart, portEnd);

  // 创建进度条
  const progressBar = new ProgressBar(':percent | elapsed :elapseds | estimated :etas [:bar]', {
    total: portEnd - portStart,
    clear: true,
  });

  const foundPorts = [];
  for (let port = portStart; port <= portEnd; port++) {
    progressBar.tick();

    const status = await checkPortStatus(host, port);
    if (status) {

      // 为了让界面显示更完美，需要清除终端最后两行的内容
      process.stdout.write(clc.erase.line);
      process.stdout.write(clc.move.up(1));
      console.log('  - %s', clc.green(port));

      foundPorts.push(port);
    }
  }
  console.log('Total find %s port(s), Done.', foundPorts.length);
  return foundPorts;
}

/**
 * 解析端口范围
 *
 * @param {String} str
 * @return {Array}
 */
function parseRange(str) {
  const r = str.match(REGEXP_PORT_RANGE);
  if (!r) {
    throw new TypeError(`parse port range failed: ${ str }`);
  }
  return [ Number(r[1]), Number(r[2]) ];
}

/**
 * 打印帮助信息
 */
function printHelp() {
  console.log(`
Usage:

  scan <host> <portStart-portEnd>

Example:

  scan 127.0.0.1 1-65525
  scan example.com 1000-10000

  `);
}

/**
 * 主函数
 */
async function main() {

  // 获取命令参数
  let host = argv._[0];
  const range = parseRange(argv._[1] || '1-65535');

  // 打印帮助信息
  if (argv.help || !host) {
    printHelp();
    return;
  }

  // 如果是域名则先将其解析成IP地址
  if (!isIPAddress(host)) {
    host = await resolveDNS(host);
  }

  // 开始扫描
  await checkPortRange(host, range[0], range[1]);
}

main()
  .then(() => process.exit())
  .catch(err => {
    console.error(err);
    process.exit(1);
  });