代码适用于 Python 3.6，但不适用于 3.7

Question

I started to learn python and sockets those days and I made a simple client-server app just to make some tests and it works fine with Python 3.6, but gives me error in the newest version.

Server.py

import socket, ssl

context = ssl.create_default_context(ssl.Purpose.CLIENT_AUTH)
context.verify_mode = ssl.CERT_REQUIRED
context.load_cert_chain(certfile="SSL/server.crt", keyfile="SSL/server.key")
context.load_verify_locations("SSL/client.crt")

bindsocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
bindsocket.bind(("127.0.0.1", 65405))
bindsocket.listen(10)

while True:
    newsocket, fromaddr = bindsocket.accept()
    print(newsocket)
    connstream = context.wrap_socket(newsocket, server_side=True)
    try:
        print(connstream.getpeercert())
    finally:
        connstream.shutdown(socket.SHUT_RDWR)
        connstream.close()

Client.py

import ssl, socket

context = ssl.create_default_context(ssl.Purpose.SERVER_AUTH)
context.load_cert_chain(certfile="SSL/client.crt", keyfile="SSL/client.key")
context.verify_mode = ssl.CERT_REQUIRED
context.check_hostname = True
context.load_verify_locations("SSL/server.crt")

conn = context.wrap_socket(socket.socket(socket.AF_INET, socket.SOCK_STREAM), server_hostname="127.0.0.1")

try:
    conn.connect(("127.0.0.1", 65405))
    conn.sendall(b"aff")
    print(conn.getpeercert())
except:
    print("não")
finally:
    conn.shutdown(socket.SHUT_RDWR)
    conn.close()

Error

Traceback (most recent call last):
    File "C:/Users/nicol/Desktop/Kyuu/Bot/Kaori/Python/server.py", line 15, in <module>
    connstream = context.wrap_socket(newsocket, server_side=True)
    File "C:\Users\nicol\AppData\Local\Programs\Python\Python37\lib\ssl.py", line 412, in wrap_socket
    session=session
    File "C:\Users\nicol\AppData\Local\Programs\Python\Python37\lib\ssl.py", line 853, in _create
    self.do_handshake()
    File "C:\Users\nicol\AppData\Local\Programs\Python\Python37\lib\ssl.py", line 1117, in do_handshake
    self._sslobj.do_handshake()
ssl.SSLError: [SSL: SSLV3_ALERT_BAD_CERTIFICATE] sslv3 alert bad certificate (_ssl.c:1056)

Edit 1

I tried to use ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER) and ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT), but I got the same error.

Edit 2

When I use the command "s_client -connect 127.0.0.1:65405 -cert client.pem -key client.pem -CAfile server.crt" in the OpenSSL it works fine

Answer 1

Many old protocols are disabled since Python v3.6, namely

This might happen due server and client run on different python versions (3.6 vs 3.7).