Go语言高并发实现端口扫描器

• 学了GO不玩一下那不是很浪费 写了一个端口扫描器 大家可以一起学习下

package main

import (
    "flag"
    "fmt"
    "net"
    "runtime"
    "time"
)

func main() {

    cores := runtime.NumCPU()
    runtime.GOMAXPROCS(cores - 1)

    domainP := flag.String("domain", "", "请输入指定的IP地址")

    flag.Parse()

    domain := *domainP

    if domain == "" {
        fmt.Println("请输入IP地址")
        return
    }

    openPort := make([]int, 10)

    exitChan := make(chan bool)

    portChan := make(chan int)

    resChan := make(chan int, 100)

    go func() {
        for i := 0; i < 65535; i++ {
            portChan <- i
        }
        close(portChan) //及时关闭管道 使用for循环取出时才不会等待
    }()
    timeout := time.Millisecond * 200

    for i := 0; i < 18; i++ {
        go CheckIsOpen(domain, timeout, portChan, exitChan, openPort, resChan)
    }

    for i := 0; i < 18; i++ {
        <-exitChan
    }

    close(exitChan)
    close(resChan)
    fmt.Println("开启的端口号:")
    for {
        port, res := <-resChan

        if !res {
            break
        }

        fmt.Println(port)

    }
}

//检查端口是否打卡
func CheckIsOpen(domain string, timeout time.Duration, portChan chan int, exitChan chan bool, openPort []int, reschan chan int) {
    for {
        port, ok := <-portChan

        if !ok {
            break
        }

        socket := fmt.Sprintf("%v:%v", domain, port)

        _, err := net.DialTimeout("tcp", socket, timeout) //发起握手操作  有回应 说明打开了端口 并且做了延时 超过一定时间 直接说明未打开

        defer func() {
            recover()
        }()

        if err == nil {
            reschan <- port
            fmt.Println(socket, " 打开")
            openPort = append(openPort, port)
        } else {
            fmt.Println(socket, " 关闭")
        }
    }

    exitChan <- true

}