网络扫描仪不返回任何内容

Question

我正在尝试开发一个用于网络扫描的Python脚本。但是，在执行时，我遇到了一个问题：终端除了调试消息之外不显示任何输出。这是当前的输出：

"PS C:\Users\Gabriel D\Desktop\Network Scanner> python scanner.py 18.177.16.0/24 -p 1-1024 -o csv
Scanning target: 18.177.16.0/24
Scanning ports: 1-1024
Output format: csv
Scanning network...
ARP responses: <Results: TCP:0 UDP:0 ICMP:0 Other:0>
Scan completed.
Scan results: {}
Results saved to 'scan_results.csv'"

这是代码：

import scapy.all as scapy
import argparse
import json

def get_arguments():
    parser = argparse.ArgumentParser(description="Network Scanner")
    parser.add_argument("target", help="Target IP address or range (CIDR notation)")
    parser.add_argument("-p", "--ports", default="1-1024", help="Ports to scan (default: 1-1024)")
    parser.add_argument("-o", "--output", choices=["json", "csv"], help="Output format (json/csv)")
    return parser.parse_args()

def scan_port(ip, port):
    try:
        print(f"Scanning port {port} on {ip}")
        src_port = 12345  # You can change this source port if needed
        response = scapy.sr1(scapy.IP(dst=ip)/scapy.TCP(sport=src_port, dport=port, flags="S"), timeout=1, verbose=False)
        print(f"Response: {response}")  # Debugging: Print the response
        if response and response.haslayer(scapy.TCP):
            print(f"Port {port} is open on {ip}")
            return port, True
        else:
            print(f"Port {port} is closed on {ip}")
            return port, False
    except Exception as e:
        print(f"Error scanning port {port} on {ip}: {e}")
        return port, False

def scan_host(ip, ports):
    print(f"Scanning ports on host {ip}")
    open_ports = []
    for port in range(ports[0], ports[1] + 1):
        result = scan_port(ip, port)
        if result[1]:
            open_ports.append(result[0])
    print(f"Open ports on host {ip}: {open_ports}")
    return {ip: open_ports}

def scan_network(target, ports_range):
    print("Scanning network...")
    hosts = scapy.ARP(pdst=target)
    answered_list = scapy.srp(hosts, timeout=1, verbose=False)[0]
    print("ARP responses:", answered_list)  # Debugging: Print the list of ARP responses

    scan_results = {}
    for element in answered_list:
        ip = element[1].psrc
        try:
            scan_results.update(scan_host(ip, ports_range))
        except Exception as e:
            print(f"Error scanning {ip}: {e}")

    print("Scan completed.")
    return scan_results

def main():
    args = get_arguments()
    target = args.target
    ports_range = list(map(int, args.ports.split("-")))

    print(f"Scanning target: {target}")
    print(f"Scanning ports: {ports_range[0]}-{ports_range[1]}")
    print(f"Output format: {args.output}")

    scan_results = scan_network(target, ports_range)
    print("Scan results:", scan_results)  # Debugging: Print the scan results

    if args.output == "json":
        with open("scan_results.json", "w") as file:
            json.dump(scan_results, file, indent=4)
        print("Results saved to 'scan_results.json'")
    elif args.output == "csv":
        with open("scan_results.csv", "w") as file:
            for ip, ports in scan_results.items():
                file.write(f"{ip},{','.join(map(str, ports))}\n")
        print("Results saved to 'scan_results.csv'")
    else:
        for ip, ports in scan_results.items():
            print(f"IP: {ip}\tOpen Ports: {', '.join(map(str, ports))}")

if __name__ == "__main__":
    main()

我希望代码返回正确的输出以及端口和任何内容

Answer 1

发送和接收 ARP PDU 的适当函数是

sr

，而不是

srp

。

srp

用于发送和接收第 2 层 PDU（例如以太网帧）。在您的脚本中，您使用

srp

。因此，您直接在线路上发送 ARP 数据包，而不将它们打包在第 2 层 PDU 中。所以这导致了一个被所有主机忽略的难以理解的框架。

例如，当我尝试请求网关的 MAC 时，下面的两个测试都可以在我的机器上运行：

>>> x = sr(ARP(pdst="192.168.15.254"))
Begin emission:
Finished sending 1 packets.
*
Received 1 packets, got 1 answers, remaining 0 packets
>>> x = srp(Ether() / ARP(pdst="192.168.15.254"))
Begin emission:
Finished sending 1 packets.
*
Received 1 packets, got 1 answers, remaining 0 packets