实现原理

tcp扫描

创建tcp客户端然后与目标地址的每个端口建立连接，如果能连接成功说明目标地址此端口已经被打开。

判断是什么协议

1. 连接成功后读取字节，如ssh协议的端口会读取到如这种的数据SSH-2.0-OpenSSH_7.4;
2. 创建http/s客户端与已经扫描出来的端口进行请求，返回数据如&{403 Forbidden 403 HTTP/1.1 1 1 map[Content-Length:[548] Content-Type:[text/html] Date:[Thu, 09 Jun 2022 08:16:50 GMT] Server:[nginx]] 0xc0015ba2e0 548 [] true false map[] 0xc0015d0400 <nil>}

代码实现

package main

import (
	"fmt"
	"log"
	"net"
	"runtime"
	"strconv"
	"strings"
	"sync"
	"time"

	gt "github.com/mangenotwork/gathertool"
)


// 队列
type Queue struct {
	mux *sync.Mutex
	list []int
}

// Add 向队列中添加元素
func (q *Queue) Add(i int) error {
	q.mux.Lock()
	defer q.mux.Unlock()
	q.list = append(q.list,i)
	return nil
}

// Poll 移除队列中最前面的额元素
func (q *Queue) Poll() int {
	q.mux.Lock()
	defer q.mux.Unlock()
	if q.IsEmpty() {
		return 0
	}
	first := q.list[0]
	q.list = q.list[1:]
	return first
}

func (q *Queue) IsEmpty() bool {
	if len(q.list) == 0 {
		return true
	}
	return false
}


func main(){

	gt.CloseLog()
	runtime.GOMAXPROCS(runtime.NumCPU())
	ip := "192.168.0.197"
	q := &Queue{
		mux : &sync.Mutex{},
		list : make([]int,0),
	}
	for i:=1; i<65000;i++ {
		_=q.Add(i)
	}


	var wg sync.WaitGroup
	for job:=0;job<888;job++{
		wg.Add(1)
		go func(i int){
			defer wg.Done()
			for {
				port := q.Poll()
				if port == 0 {
					break
				}
				ok, conn := ScanPort(ip, port)
				if  ok{
					addr := fmt.Sprintf("%s:%d", ip, port)
					log.Println(fmt.Sprintf("%s:%d is open", ip, port))
					// 判断是什么

					// 1. 判断 读取 net.Conn 返回
					readTimeout := 3*time.Second
					buffer := make([]byte, 1024)
					err := conn.SetReadDeadline(time.Now().Add(readTimeout)) // timeout
					if err != nil {
						log.Println("setReadDeadline failed:", err)
					}
					_, _ = conn.Read(buffer)

					bufStr := string(buffer)
					if strings.Index(bufStr, "SSH") != -1 {
						log.Println("扫描出 --> ", addr, " [ssh端口], msg: ", bufStr)
						break
					}
					if strings.Index(bufStr, "mysql") != -1 {
						log.Println("扫描出 --> ", addr, " [mysql端口], msg: ", bufStr)
						break
					}
					_= conn.Close()

					if port == 80 {
						ctx, err := gt.Get("http://"+addr)
						if err != nil {
							log.Println("扫描出 --> ", addr, " [http端口] 网络不可到", err)
						}else {
							log.Println("扫描出 --> ", addr, " [http端口] ",ctx.Resp)
						}
						break
					}

					if port == 443 {
						ctx, err := gt.Get("https://"+addr)
						if err != nil {
							log.Println("扫描出 --> ", addr, " [https端口] 网络不可到", err)
						}else {
							log.Println("扫描出 --> ", addr, " [https端口] ",ctx.Resp)
						}
						break
					}

					// 2. 判断是否 http/s 协议
					ctxHttp, err := gt.Get("http://"+addr)
					if err == nil {
						log.Println("扫描出 --> ", addr, " [http端口] ",ctxHttp.Resp)
						break
					}

					ctxHttps, err := gt.Get("https://"+addr)
					if err == nil {
						log.Println("扫描出 --> ", addr, " [http端口] ",ctxHttps.Resp)
						break
					}

				}
			}
		}(job)
	}
	wg.Wait()
}


func ScanPort(hostname string, port int) (bool, net.Conn) {
	//fmt.Printf("scanning port %d \n", port)
	p := strconv.Itoa(port)
	addr := net.JoinHostPort(hostname, p)
	conn, err := net.DialTimeout("tcp", addr, 5*time.Second)
	if err != nil {
		return false, nil
	}
	return true, conn
}

// 需求，扫描端口 并查看是什么协议
// 暴力 ssh, mysql, redis
//

结果