sslcontext.py 文件源码

def create_ssl_context(verify=True, cafile=None, capath=None):
    """Set up the SSL context.
    """
    # This is somewhat tricky to do it right and still keep it
    # compatible across various Python versions.

    try:
        # The easiest and most secure way.
        # Requires either Python 2.7.9 or 3.4 or newer.
        context = ssl.create_default_context(cafile=cafile, capath=capath)
        if not verify:
            context.check_hostname = False
            context.verify_mode = ssl.CERT_NONE
    except AttributeError:
        # ssl.create_default_context() is not available.
        try:
            context = ssl.SSLContext(ssl.PROTOCOL_TLSv1_2)
        except AttributeError:
            # We don't even have the SSLContext class.  This smells
            # Python 2.7.8 or 3.1 or older.  Bad luck.
            return None

        context.options |= ssl.OP_NO_SSLv2
        context.options |= ssl.OP_NO_SSLv3
        if verify:
            context.verify_mode = ssl.CERT_REQUIRED
            if cafile or capath:
                context.load_verify_locations(cafile, capath)
            else:
                context.set_default_verify_paths()
        else:
            context.verify_mode = ssl.CERT_NONE
    return context