Question

我使用后面的代码进行端口扫描。主要问题和其他问题如下：

为什么下面标题为主要问题的部分没有读取ACK数据包？如果港口正在发放横幅或者我必须发送特定的东西，发送任何东西会产生横幅吗？（见第二个问题）

import threading
import socket
from socket import *

def scan(ip, port, banners):
    try:
        sock = socket(AF_INET, SOCK_STREAM)
        sock.connect((ip, port))

        //MAIN QUESTION
        //I WAS HOPING THIS WOULD READ ACK PACKETS
        results = connSkt.recv(100)

        //SECOND QUESTION
        //I WAS HOPING THIS WOULD RESULT IN A BANNER
        sock.send("Doesntmatter\r\n")

        print(results)
        banners[i] = results
        sock.close()
    except:
        pass

def main():
    ip = "74.125.224.72"
    banners = dict()

    setdefaulttimeout(1)
    for ports in range(1,1000):
        t = threading.Thread(target=scan, args=(ip, int(ports), banners))
        t.start()

    for keys in banners:
        print("Port: " + keys + "\n" + "Banner: " + banners[keys])

    exit(0)


main()

Answer 1

    //I WAS HOPING THIS WOULD READ ACK PACKETS
   results = connSkt.recv(100)

为什么你会这么想？（a）您尚未发送任何内容，因此无需确认，并且（b）套接字API不会将ACK数据包返回给应用程序。它们在TCP堆栈中处理。

   //SECOND QUESTION
   //I WAS HOPING THIS WOULD RESULT IN A BANNER
   sock.send("Doesntmatter\r\n")

同样，你为什么期待呢？发送数据不会产生横幅。您必须接收某些东西，而且似乎是横幅，这意味着对等应用程序必须发送横幅，其中大部分都没有。

为什么我的扫描仪不读取ACK数据包？

1 个答案: