写一个echo-reply的实现程序
时间: 2024-05-14 13:19:30 浏览: 18
好的,可以参考以下代码:
```python
while True:
user_input = input("User: ")
print("EchoBot: " + user_input)
```
这段代码会不断循环,接收用户输入并输出相同的回复,实现了“echo-reply”的功能。
相关问题
写一个echo-reply的实现程序,这个程序通过UDP协议监听本地的9999端口,一旦收到数据,就会将数据原样回传给发送端。测试时可以用任意工具向本机的999端口发送数据
好的,我明白你的要求了。以下是一个简单的echo-reply的实现程序,你可以根据需要进行修改:
```
import socket
HOST = '127.0.0.1' # 监听的主机地址
PORT = 9999 # 监听的端口号
def main():
# 创建UDP Socket
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
# 绑定Socket到指定的地址和端口
sock.bind((HOST, PORT))
print('Echo-Reply Server started at {}:{}'.format(HOST, PORT))
while True:
data, address = sock.recvfrom(1024)
print('Received data from {}: {}'.format(address, data))
sock.sendto(data, address)
print('Echoed data back to {}: {}'.format(address, data))
if __name__ == '__main__':
main()
```
你可以在命令行中运行该程序,然后使用任意工具向本地的9999端口发送数据进行测试。程序会将收到的数据原样回传给发送端。
实现ping程序
好的,实现Ping程序需要使用ICMP协议。以下是一个简单的Python实现,可以用于Linux和Windows系统:
```python
import os
import sys
import struct
import socket
import select
import time
# 计算校验和
def checksum(data):
n = len(data)
m = n % 2
sum = 0
for i in range(0, n - m, 2):
sum += (data[i]) + ((data[i+1]) << 8)
if m:
sum += (data[-1])
sum = (sum >> 16) + (sum & 0xffff)
sum += (sum >> 16)
result = (~sum) & 0xffff
result = result >> 8 | (result << 8 & 0xff00)
return result
# 发送ICMP请求报文
def send_ping(sock, dest_addr, pid, seq):
# 构造ICMP请求报文
icmp_type = 8 # ICMP Echo Request
icmp_code = 0
icmp_checksum = 0
icmp_id = pid & 0xffff
icmp_seq = seq & 0xffff
icmp_data = b'Hello, World!'
icmp_checksum = checksum(struct.pack('!BBHHH', icmp_type, icmp_code, icmp_checksum, icmp_id, icmp_seq) + icmp_data)
icmp_packet = struct.pack('!BBHHH', icmp_type, icmp_code, icmp_checksum, icmp_id, icmp_seq) + icmp_data
# 发送ICMP请求报文
sock.sendto(icmp_packet, (dest_addr, 0))
# 接收ICMP响应报文
def receive_ping(sock, pid, seq, timeout):
time_left = timeout
while True:
# 设置超时时间
start_time = time.time()
ready = select.select([sock], [], [], time_left)
elapsed = (time.time() - start_time)
if not ready[0]:
return None, None, None, None, None
# 接收到ICMP响应报文
pkt, addr = sock.recvfrom(1024)
icmp_header = pkt[20:28]
icmp_type, icmp_code, icmp_checksum, icmp_id, icmp_seq = struct.unpack('!BBHHH', icmp_header)
# 判断是否为ICMP响应报文
if icmp_type == 0 and icmp_id == pid and icmp_seq == seq:
icmp_data = pkt[28:]
return addr[0], icmp_type, icmp_code, icmp_checksum, icmp_data
# 更新超时时间
time_left -= elapsed
if time_left <= 0:
return None, None, None, None, None
# Ping指定主机
def ping(dest_addr, count, timeout):
# 创建原始套接字
sock = socket.socket(socket.AF_INET, socket.SOCK_RAW, socket.IPPROTO_ICMP)
pid = os.getpid() & 0xffff
for i in range(count):
seq = i + 1
# 发送ICMP请求报文
send_ping(sock, dest_addr, pid, seq)
# 接收ICMP响应报文
addr, icmp_type, icmp_code, icmp_checksum, icmp_data = receive_ping(sock, pid, seq, timeout)
# 输出结果
if addr is not None:
print('Reply from {}: icmp_seq={}, time={}ms'.format(addr, seq, round(icmp_checksum * 1000 / timeout)))
else:
print('Request timed out.')
sock.close()
if __name__ == '__main__':
if len(sys.argv) < 2:
print('Usage: python ping.py <host> [count] [timeout]')
else:
dest_addr = sys.argv[1]
count = int(sys.argv[2]) if len(sys.argv) > 2 else 4
timeout = int(sys.argv[3]) if len(sys.argv) > 3 else 1000
ping(dest_addr, count, timeout)
```
您可以将以上代码保存为ping.py,并在终端中运行以下命令来Ping指定主机:
```
python ping.py <host> [count] [timeout]
```
其中,<host>为目标主机的IP地址或域名,[count]为Ping包数量,默认为4,[timeout]为超时时间(毫秒),默认为1000。