fly6516
71a8e81f68
- 新增原理解释文档，详细说明了 ICMP、UDP 和 TCP 报文的构建与发送原理 - 新增校验和计算文档，提供了正确的 ICMP 校验和计算方法 - 这些文档有助于开发者更好地理解网络报文的构建和发送过程
258 lines
7.5 KiB
Python
258 lines
7.5 KiB
Python
import tkinter as tk
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from tkinter import ttk, messagebox
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import socket
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import struct
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import time
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import uuid
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import re
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# 获取本机信息
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def get_local_info():
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"""
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获取本机的主机名、MAC地址和IP地址列表。
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Returns:
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tuple: 包含主机名、MAC地址和IP地址列表的元组。
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"""
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hostname = socket.gethostname()
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local_ips = socket.gethostbyname_ex(hostname)[-1]
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mac = ':'.join(re.findall('..', '%012x' % uuid.getnode()))
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return hostname, mac, local_ips
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# 验证 IP 地址或域名
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def validate_ip_or_domain(value):
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"""
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验证输入值是否为有效的IP地址或域名。
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Args:
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value (str): 待验证的IP地址或域名。
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Returns:
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bool: 如果输入值有效返回True，否则返回False。
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"""
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ip_pattern = re.compile(r'^\d{1,3}(\.\d{1,3}){3}$')
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domain_pattern = re.compile(r'^([a-zA-Z0-9-]+\.)+[a-zA-Z]{2,}$')
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return ip_pattern.match(value) or domain_pattern.match(value)
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# 验证端口号
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def validate_port(port):
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"""
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验证输入的端口号是否有效。
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Args:
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port (str): 待验证的端口号。
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Returns:
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bool: 如果端口号有效返回True，否则返回False。
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"""
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return port.isdigit() and 1 <= int(port) <= 65535
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# 构造 IP 头部
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def construct_ip_header(src_ip, dest_ip, payload_length, protocol):
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"""
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构造IP头部。
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Args:
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src_ip (str): 源IP地址。
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dest_ip (str): 目标IP地址。
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payload_length (int): 负载长度。
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protocol (int): 协议号。
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Returns:
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bytes: 构造的IP头部。
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"""
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version = 4
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ihl = 5
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tos = 0
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total_length = 20 + payload_length
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identification = 54321
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flags_offset = 0
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ttl = 64
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header_checksum = 0
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src_ip_bytes = socket.inet_aton(src_ip)
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dest_ip_bytes = socket.inet_aton(dest_ip)
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ip_header = struct.pack('!BBHHHBBH4s4s',
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(version << 4) + ihl, tos, total_length,
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identification, flags_offset, ttl, protocol,
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header_checksum, src_ip_bytes, dest_ip_bytes)
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return ip_header
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# 构造 ICMP 报文
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def construct_icmp():
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"""
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构造ICMP报文。
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Returns:
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bytes: 构造的ICMP报文。
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"""
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# ICMP 报文头部: 类型(8), 代码(0), 校验和(0), 标识符(1), 序列号(1)
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icmp_header = struct.pack('!BBHHH', 8, 0, 0, 1, 1)
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data = b'Ping'
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# 计算校验和
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checksum = calculate_checksum(icmp_header + data)
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# 填充校验和字段
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icmp_header = struct.pack('!BBHHH', 8, 0, checksum, 1, 1)
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return icmp_header + data
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# 构造 UDP 报文
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def construct_udp(src_port, dest_port):
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"""
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构造UDP报文。
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Args:
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src_port (int): 源端口号。
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dest_port (int): 目标端口号。
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Returns:
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bytes: 构造的UDP报文。
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"""
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udp_header = struct.pack('!HHHH', src_port, dest_port, 8, 0)
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return udp_header
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# 构造 TCP 报文（SYN）
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def construct_tcp(src_port, dest_port):
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"""
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构造TCP报文（SYN）。
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Args:
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src_port (int): 源端口号。
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dest_port (int): 目标端口号。
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Returns:
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bytes: 构造的TCP报文。
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"""
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seq = 0
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ack_seq = 0
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offset = 5
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reserved = 0
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flags = 0b000010 # SYN flag
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window = socket.htons(5840)
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checksum = 0
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urgent_ptr = 0
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tcp_header = struct.pack('!HHLLBBHHH',
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src_port, dest_port, seq, ack_seq,
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(offset << 4) + reserved, flags, window,
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checksum, urgent_ptr)
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return tcp_header
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# 计算校验和
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def calculate_checksum(data):
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"""
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计算校验和。
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Args:
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data (bytes): 待计算校验和的数据。
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Returns:
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int: 计算得到的校验和。
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"""
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checksum = 0
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n = len(data)
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# 按 16 位块划分
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for i in range(0, n - 1, 2):
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chunk = (data[i] << 8) + data[i + 1]
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checksum += chunk
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# 如果长度为奇数，补零
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if n % 2 == 1:
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checksum += data[-1] << 8
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# 将 32 位总和折叠为 16 位
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checksum = (checksum >> 16) + (checksum & 0xFFFF)
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checksum += (checksum >> 16)
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# 对总和取反
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return ~checksum & 0xFFFF
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# 发送报文
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def send_packet():
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"""
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发送报文。
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"""
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try:
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src_ip = ip_combobox.get()
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dest_host = dest_entry.get()
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dest_port = port_entry.get()
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packet_type = var.get()
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# 验证目标地址
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if not validate_ip_or_domain(dest_host):
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raise ValueError("目标地址无效，必须为有效的 IP 或域名")
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# 验证端口号
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if not validate_port(dest_port):
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raise ValueError("端口号无效，必须是有效的正整数（1-65535）")
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dest_ip = socket.gethostbyname(dest_host)
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src_port = 12345
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dest_port = int(dest_port)
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# 构造报文并发送
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if packet_type == "ICMP":
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sock = socket.socket(socket.AF_INET, socket.SOCK_RAW, socket.IPPROTO_ICMP)
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packet = construct_icmp()
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elif packet_type == "UDP":
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sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
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packet = construct_udp(src_port, dest_port)
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elif packet_type == "TCP":
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sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
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sock.connect((dest_ip, dest_port))
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packet = b"Hello, TCP!" # TCP 是面向连接的，这里发送简单的字符串
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sock.sendall(packet)
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sock.close()
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result.set(f"TCP 连接成功，数据已发送！")
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return # 结束函数
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# 发送报文
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sock.sendto(packet, (dest_ip, dest_port))
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result.set(f"报文发送成功！类型: {packet_type}")
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except socket.gaierror:
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messagebox.showerror("网络错误", "无法解析目标地址，请检查输入的 IP 或域名是否正确。")
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except socket.error as e:
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messagebox.showerror("网络错误", f"网络错误: {e.strerror}")
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except ValueError as e:
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messagebox.showerror("输入错误", f"输入无效: {e}")
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except Exception as e:
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messagebox.showerror("未知错误", f"发送报文时发生未知错误: {e}")
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# GUI 界面设计
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window = tk.Tk()
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window.title("网络通信软件")
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hostname, mac, local_ips = get_local_info()
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tk.Label(window, text="本机信息:").grid(row=0, column=0)
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info_text = tk.Text(window, height=4, width=40)
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info_text.grid(row=0, column=1, columnspan=2)
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info_text.insert(tk.END, f"主机名: {hostname}\nMAC 地址: {mac}\n可用 IP: {', '.join(local_ips)}")
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info_text.config(state=tk.DISABLED)
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tk.Label(window, text="本机 IP 地址:").grid(row=1, column=0)
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ip_combobox = ttk.Combobox(window, values=local_ips)
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ip_combobox.grid(row=1, column=1)
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ip_combobox.current(0)
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tk.Label(window, text="目标地址:").grid(row=2, column=0)
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dest_entry = tk.Entry(window)
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dest_entry.grid(row=2, column=1)
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tk.Label(window, text="目标端口:").grid(row=3, column=0)
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port_entry = tk.Entry(window)
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port_entry.grid(row=3, column=1)
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tk.Label(window, text="报文类型:").grid(row=4, column=0)
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var = tk.StringVar(value="ICMP")
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tk.Radiobutton(window, text="ICMP", variable=var, value="ICMP").grid(row=4, column=1)
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tk.Radiobutton(window, text="UDP", variable=var, value="UDP").grid(row=4, column=2)
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tk.Radiobutton(window, text="TCP", variable=var, value="TCP").grid(row=4, column=3)
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result = tk.StringVar()
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tk.Label(window, textvariable=result).grid(row=6, column=0, columnspan=3)
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tk.Button(window, text="发送报文", command=send_packet).grid(row=5, column=1)
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window.mainloop()
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