urllib2 SSL3_CHECK_CERT_AND_ALGORITHM：dh 密钥太小答案

【问题标题】：urllib2 SSL3_CHECK_CERT_AND_ALGORITHM: dh key too smallurllib2 SSL3_CHECK_CERT_AND_ALGORITHM：dh 密钥太小
【发布时间】：2019-02-25 15:37:46
【问题描述】：

尝试使用 suds 发送 SOAP 请求，我正在使用 Python 2.7.6。

我不是很精通安全问题我被引导相信无论是我的机器还是服务器机器上的安全密钥太小，我不知道如何解决。我是否会生成一些新密钥并创建自定义开瓶器？任何帮助/指导都会有所帮助。

堆栈跟踪：

Traceback (most recent call last):
  File "read_xml.py", line 71, in <module>
    client.service.PO(purchase_orders)
  File "/usr/local/lib/python2.7/dist-packages/suds/client.py", line 542, in __call__
    return client.invoke(args, kwargs)
  File "/usr/local/lib/python2.7/dist-packages/suds/client.py", line 602, in invoke
    result = self.send(soapenv)
  File "/usr/local/lib/python2.7/dist-packages/suds/client.py", line 637, in send
    reply = transport.send(request)
  File "/usr/local/lib/python2.7/dist-packages/suds/transport/https.py", line 64, in send
    return  HttpTransport.send(self, request)
  File "/usr/local/lib/python2.7/dist-packages/suds/transport/http.py", line 77, in send
    fp = self.u2open(u2request)
  File "/usr/local/lib/python2.7/dist-packages/suds/transport/http.py", line 118, in u2open
    return url.open(u2request, timeout=tm)
  File "/usr/lib/python2.7/urllib2.py", line 404, in open
    response = self._open(req, data)
  File "/usr/lib/python2.7/urllib2.py", line 422, in _open
    '_open', req)
  File "/usr/lib/python2.7/urllib2.py", line 382, in _call_chain
    result = func(*args)
  File "/usr/lib/python2.7/urllib2.py", line 1222, in https_open
    return self.do_open(httplib.HTTPSConnection, req)
  File "/usr/lib/python2.7/urllib2.py", line 1184, in do_open
    raise URLError(err)
urllib2.URLError: <urlopen error [Errno 1] _ssl.c:510: error:14082174:SSL routines:SSL3_CHECK_CERT_AND_ALGORITHM:dh key too small>

我正在查看以下链接

Python - requests.exceptions.SSLError - dh key too small

https://bugs.python.org/issue24985

https://unix.stackexchange.com/questions/333877/how-to-find-which-key-exactly-dh-key-too-small-openssl-error-is-about

不确定如何实现他们所说的，再次感谢您的帮助

【问题讨论】：

您必须将连接配置为不使用 Diffie-Helman (DH) 或更改服务器上的内容，遵循 weakdh.org/sysadmin.html 的说明。如果您控制服务器，最好修复其安全性，从而更改其 dhparams，如上一个链接中所述。如果你不控制服务器，你必须使用第一个选项。

标签： python security ssl soap urllib2

【解决方案1】：

我在 Python 3.7 中使用这个代码片段：

import ssl
from urllib.request import HTTPSHandler

from suds.transport.https import HttpAuthenticated


class SSLAuthenticated(HttpAuthenticated):
    """ Enables SSL context for Suds. """

    def __init__(self, ssl_ciphers: str = ssl._DEFAULT_CIPHERS, **kwargs):
        self.ssl_ciphers = ssl_ciphers
        super().__init__(**kwargs)

    def u2handlers(self):
        handlers = super().u2handlers()
        ssl_context = ssl.create_default_context()
        if self.ssl_ciphers is not None:
            ssl_context.set_ciphers(self.ssl_ciphers)
        ssl_context_handler = HTTPSHandler(context=ssl_context)
        handlers = [ssl_context_handler] + handlers
        return handlers

client = suds.Client(transport=SSLAuthenticated(ssl_ciphers='HIGH:!DH'))

要获取网站上可用密码的列表，请运行：

nmap --script ssl-enum-ciphers -p 443 affected.website.com

从 A 级密码中逐一选择并检查它们，如下所示：

openssl s_client -connect affected.website.com:443 -cipher 'HIGH:!DH' -brief

【讨论】：

【解决方案2】：

我通过在/etc/ssl/openssl.cnf 中更改DEFAULT@SECLEVEL=2 -> DEFAULT@SECLEVEL=1 解决了这个问题

【讨论】：