如何重现"由同行重置连接"

时间:2016-11-24 01:52:46

标签: python sockets networking tcp network-programming

我已经了解了tcp中两个臭名昭着的错误之间的区别:

  • [Errno 54] Connection reset by peer
  • [Errno 32] Broken pipe

这两个错误都是tcp连接的一侧因未知原因而关闭,而另一方仍然与之通信。

  • 当另一边write某事,Broken pipe被抛出时
  • 当另一边read某事,Connection reset by peer被抛出时

我能够使用下面的Python代码重现Broken pipe

# tcp_server.py
def handler(client_sock, addr):
    try:
        print('new client from %s:%s' % addr)
    finally:
        client_sock.close()   # close current connection directly

if __name__ == '__main__':

    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    sock.bind(('', 5500))
    sock.listen(5)

    while 1:
        client_sock, addr = sock.accept()
        handler(client_sock, addr)

至于客户,

>>> sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
>>> sock.connect(('', 5500))
>>> sock.send('a')
1
>>> sock.send('a')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
socket.error: [Errno 32] Broken pipe

当客户端首先send时,从服务器向客户端发送RST数据包,从此刻起,send将始终抛出Broken pipe

以上所有内容都在我的理解之内。但是,当客户端从服务器读取时,它总是返回空字符串而不是抛出Connection reset by peer

>>> sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
>>> sock.connect(('', 5500))
>>> sock.recv(1024)
''
>>> sock.recv(1024)
''
>>> sock.recv(1024)
''
>>> sock.recv(1024)

我对此感到困惑,或者一般如何重现Connection reset by peer

1 个答案:

答案 0 :(得分:2)

您可以设置套接字&#34;逗留&#34;选项为0并关闭套接字以发送重置。更新服务器

import socket
import struct
import time

# tcp_server.py
def handler(client_sock, addr):
    try:
        print('new client from %s:%s' % addr)
        time.sleep(1)
    finally:
        client_sock.setsockopt(socket.SOL_SOCKET, socket.SO_LINGER,
            struct.pack('ii', 1, 0))
        client_sock.close()   # close current connection directly

if __name__ == '__main__':

    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
    sock.bind(('', 5500))
    sock.listen(5)

    while 1:
        client_sock, addr = sock.accept()
        handler(client_sock, addr)

运行此客户端

import socket
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('', 5500))
print(sock.recv(1024))

我得到了

Traceback (most recent call last):
  File "tcpclient.py", line 5, in <module>
    print(sock.recv(1024))
ConnectionResetError: [Errno 104] Connection reset by peer