call: _do_ssl_shutdown() -> shutdown(), err: Error([('SSL routines', '', 'shutdown while in init')]) about pyftpdlib HOT 3 OPEN

Well I just modified the module's source code and now figured out that the Exception was handled by except SSL.Error.

from pyftpdlib.

I modified the source code to this:

            except SSL.Error as err:
                debug("SSL.Error call: _do_ssl_shutdown() -> shutdown(), err: %r" % err,
                      inst=self)
                # see:
                # https://github.com/giampaolo/pyftpdlib/issues/171
                # https://bugs.launchpad.net/pyopenssl/+bug/785985
                print(err)
                print(err.args)
                print(err.errno)
                if err.args and not getattr(err, "errno", None):
                    pass
                else:
                    raise

And it raised an error without doubt, saying that the Error object does not have an attribute named "errno".

However, I don't know when will the SSL.Error object have a attribute named this. I found that this exception class inherits from the built-in class of Exception, but it does not overload a new errno property in it, and this property is not owned by the built-in Exception class.

In summary, since the errno property never seems to exist, getattr() will always return its set default value None, and make the latter condition in the if statement always true; Err.args will always exist and have value because it returns the error number and description string of the exception, so this statement will cause the exception to always be ignored, resulting in an infinite loop of exception handling logic that I have not yet figured out.

from pyftpdlib.

Oh, I just looked up the code defining the other exceptions. It seems that the OSError class additionally defines the errno attribute.

However, SSL.Error seems to be less closely related to this exception class if its subclass has no other part that deals with OSError.

from pyftpdlib.