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How to implement username password authenticator for RPyC server

I am trying to secure my RpyC server connections through username and password. The documentation indeed shows an example, but it is too brief. No details were given on how exactly the password is passed from the client-side. Anyone figured out how to do that? Thanks in advance.

Answering my own question:
I had to override some internal methods of RPyC on the client side to achieve the desired behaviour. I don't know if much cleaner solution exists, but this seems to be a plausible one.
Server:
import rpyc
from rpyc.utils.authenticators import AuthenticationError
def magic_word_authenticator(sock):
if sock.recv(5).decode() != "Ma6ik":
raise AuthenticationError("wrong magic word")
return sock, None
class SecuredService(rpyc.Service):
def exposed_secured_op(self):
return 'Secret String'
rpyc.ThreadedServer(
service=SecuredService, hostname='localhost',
port=18812, authenticator=magic_word_authenticator
).start()
Client:
import rpyc
import traceback
class AuthSocketStream(rpyc.SocketStream):
#classmethod
def connect(cls, *args, authorizer=None, **kwargs):
stream_obj = super().connect(*args, **kwargs)
if callable(authorizer):
authorizer(stream_obj.sock)
return stream_obj
def rpyc_connect(host, port, service=rpyc.VoidService, config={}, ipv6=False, keepalive=False, authorizer=None):
s = AuthSocketStream.connect(
host, port, ipv6=ipv6, keepalive=keepalive,
authorizer=authorizer
)
return rpyc.connect_stream(s, service, config)
print('With correct authorizer')
conn1 = rpyc_connect(
'localhost', 18812, authorizer=lambda sock: sock.send('Ma6ik'.encode())
)
print(conn1.root.secured_op())
print('With wrong authorizer')
conn2 = rpyc_connect(
'localhost', 18812, authorizer=lambda sock: sock.send('Invalid'.encode())
)
try:
conn2.root
except Exception:
print(traceback.format_exc())
print('With no authorizer')
conn3 = rpyc_connect(
'localhost', 18812
)
try:
conn3.root
except Exception:
print(traceback.format_exc())
Client Console Log:
With correct authorizer
Secret String
With wrong authorizer
Traceback (most recent call last):
File "/home/client.py", line 40, in <module>
conn2.root
File "/usr/lib/python3.10/site-packages/rpyc/core/protocol.py", line 507, in root
self._remote_root = self.sync_request(consts.HANDLE_GETROOT)
File "/usr/lib/python3.10/site-packages/rpyc/core/protocol.py", line 474, in sync_request
return self.async_request(handler, *args, timeout=timeout).value
File "/usr/lib/python3.10/site-packages/rpyc/core/async_.py", line 101, in value
self.wait()
File "/usr/lib/python3.10/site-packages/rpyc/core/async_.py", line 48, in wait
self._conn.serve(self._ttl)
File "/usr/lib/python3.10/site-packages/rpyc/core/protocol.py", line 387, in serve
data = self._channel.poll(timeout) and self._channel.recv()
File "/usr/lib/python3.10/site-packages/rpyc/core/channel.py", line 55, in recv
header = self.stream.read(self.FRAME_HEADER.size)
File "/usr/lib/python3.10/site-packages/rpyc/core/stream.py", line 260, in read
raise EOFError("connection closed by peer")
EOFError: connection closed by peer
With no authorizer
Traceback (most recent call last):
File "/home/client.py", line 52, in <module>
conn3.root
File "/usr/lib/python3.10/site-packages/rpyc/core/protocol.py", line 507, in root
self._remote_root = self.sync_request(consts.HANDLE_GETROOT)
File "/usr/lib/python3.10/site-packages/rpyc/core/protocol.py", line 474, in sync_request
return self.async_request(handler, *args, timeout=timeout).value
File "/usr/lib/python3.10/site-packages/rpyc/core/async_.py", line 101, in value
self.wait()
File "/usr/lib/python3.10/site-packages/rpyc/core/async_.py", line 48, in wait
self._conn.serve(self._ttl)
File "/usr/lib/python3.10/site-packages/rpyc/core/protocol.py", line 387, in serve
data = self._channel.poll(timeout) and self._channel.recv()
File "/usr/lib/python3.10/site-packages/rpyc/core/channel.py", line 55, in recv
header = self.stream.read(self.FRAME_HEADER.size)
File "/usr/lib/python3.10/site-packages/rpyc/core/stream.py", line 260, in read
raise EOFError("connection closed by peer")
EOFError: connection closed by peer

Can't initiate get request in web.py

I'm trying to run two servers using web.py and initiating calls from one to another. Both servers start normally but when I try to call a url the below stack trace is thrown.
import web
urls = (
'/ping', 'Ping',
'/acqlock/+(.*)', 'Acquire',
)
class MSA(web.application):
def run(self, port=8081, *middleware):
func = self.wsgifunc(*middleware)
return web.httpserver.runsimple(func, ('127.0.0.1', port))
app = MSA(urls, globals())
if __name__ == "__main__":
app.run(port=8081)
class Acquire:
def GET(self, resource_name):
print resource_name
response = app.request('http://127.0.0.1:8080/acqlock/' + resource_name, method='GET')
return response
But I keep getting this error after calling the /acqlock.
Traceback (most recent call last):
File "C:\Python27\lib\site-packages\web\wsgiserver\__init__.py", line 1245, in communicate
req.respond()
File "C:\Python27\lib\site-packages\web\wsgiserver\__init__.py", line 775, in respond
self.server.gateway(self).respond()
File "C:\Python27\lib\site-packages\web\wsgiserver\__init__.py", line 2018, in respond
response = self.req.server.wsgi_app(self.env, self.start_response)
File "C:\Python27\lib\site-packages\web\httpserver.py", line 306, in __call__
return self.app(environ, xstart_response)
File "C:\Python27\lib\site-packages\web\httpserver.py", line 274, in __call__
return self.app(environ, start_response)
File "C:\Python27\lib\site-packages\web\application.py", line 279, in wsgi
result = self.handle_with_processors()
File "C:\Python27\lib\site-packages\web\application.py", line 249, in handle_with_processors
return process(self.processors)
File "C:\Python27\lib\site-packages\web\application.py", line 246, in process
raise self.internalerror()
File "C:\Python27\lib\site-packages\web\application.py", line 515, in internalerror
parent = self.get_parent_app()
File "C:\Python27\lib\site-packages\web\application.py", line 500, in get_parent_app
if self in web.ctx.app_stack:
AttributeError: 'ThreadedDict' object has no attribute 'app_stack'

Use requests library for this.
import requests
response = requests.request(method='GET', url ='http://127.0.0.1:8080/acqlock/' + resource_name)
Note: You have used port 8080 in url even though you have hosted the web.py in 8081

Error when serving html with WSGI

I am trying to make an application that serves a simple HTML form to the user and then calls a function when the user submits the form. It uses wsgiref.simple_server to serve the HTML. The server is encountering an error and I can't understand why. The code is as follows:
#!/usr/bin/python3
from wsgiref.simple_server import make_server
from wsgiref.util import setup_testing_defaults
import webbrowser # open user's web browser to url when server is run
from sys import exc_info
from traceback import format_tb
# Easily serves an html form at path_to_index with style at path_to_style
# Calls on_submit when the form is submitted, passing a dictionary with key
# value pairs { "input name" : submitted_value }
class SimpleServer:
def __init__(self, port=8000, on_submit=None, index_path="./index.html", css_path="./style.css"):
self.port = port
self.on_submit = on_submit
self.index_path = index_path
self.css_path = css_path
# Forwards request to proper method, or returns 404 page
def wsgi_app(self, environ, start_response):
urls = [
(r"^$", self.index),
(r"404$", self.error_404),
(r"style.css$", self.css)
]
path = environ.get("PATH_INFO", "").lstrip("/")
# Call another application if they called a path defined in urls
for regex, application in urls:
match = re.search(regex, path)
# if the match was found, return that page
if match:
environ["myapp.url_args"] = match.groups()
return application(environ, start_response)
return error_404(environ, start_response)
# Gives the user a form to submit all their input. If the form has been
# submitted, it sends the ouput of self.on_submit(user_input)
def index(self, environ, start_response):
# user_input is a dictionary, with keys from the names of the fields
user_input = parse_qs(environ['QUERY_STRING'])
# return either the form or the calculations
index_html = open(self.index_path).read()
body = index_html if user_input == {} else calculate(user_input)
mime_type = "text/html" if user_input == {} else "text/plain"
# return the body of the message
status = "200 OK"
headers = [ ("Content-Type", mime_type),
("Content-Length", str(len(body))) ]
start_response(status, headers)
return [body.encode("utf-8")]
def start_form(self):
httpd = make_server('', self.port, ExceptionMiddleware(self.wsgi_app))
url = "http://localhost:" + str(self.port)
print("Visit " + url)
# webbrowser.open(url)
httpd.serve_forever()
if __name__ == "__main__":
server = SimpleServer()
server.start_form()
When I run it, I get the error
127.0.0.1 - - [16/Dec/2014 21:15:57] "GET / HTTP/1.1" 500 0
Traceback (most recent call last):
File "/usr/lib/python3.4/wsgiref/handlers.py", line 138, in run
self.finish_response()
File "/usr/lib/python3.4/wsgiref/handlers.py", line 180, in finish_response
self.write(data)
File "/usr/lib/python3.4/wsgiref/handlers.py", line 266, in write
"write() argument must be a bytes instance"
AssertionError: write() argument must be a bytes instance
127.0.0.1 - - [16/Dec/2014 21:15:57] "GET / HTTP/1.1" 500 59
----------------------------------------
Exception happened during processing of request from ('127.0.0.1', 49354)
Traceback (most recent call last):
File "/usr/lib/python3.4/wsgiref/handlers.py", line 138, in run
self.finish_response()
File "/usr/lib/python3.4/wsgiref/handlers.py", line 180, in finish_response
self.write(data)
File "/usr/lib/python3.4/wsgiref/handlers.py", line 266, in write
"write() argument must be a bytes instance"
AssertionError: write() argument must be a bytes instance
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/usr/lib/python3.4/wsgiref/handlers.py", line 141, in run
self.handle_error()
File "/usr/lib/python3.4/wsgiref/handlers.py", line 368, in handle_error
self.finish_response()
File "/usr/lib/python3.4/wsgiref/handlers.py", line 180, in finish_response
self.write(data)
File "/usr/lib/python3.4/wsgiref/handlers.py", line 274, in write
self.send_headers()
File "/usr/lib/python3.4/wsgiref/handlers.py", line 331, in send_headers
if not self.origin_server or self.client_is_modern():
File "/usr/lib/python3.4/wsgiref/handlers.py", line 344, in client_is_modern
return self.environ['SERVER_PROTOCOL'].upper() != 'HTTP/0.9'
TypeError: 'NoneType' object is not subscriptable
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/usr/lib/python3.4/socketserver.py", line 305, in _handle_request_noblock
self.process_request(request, client_address)
File "/usr/lib/python3.4/socketserver.py", line 331, in process_request
self.finish_request(request, client_address)
File "/usr/lib/python3.4/socketserver.py", line 344, in finish_request
self.RequestHandlerClass(request, client_address, self)
File "/usr/lib/python3.4/socketserver.py", line 669, in __init__
self.handle()
File "/usr/lib/python3.4/wsgiref/simple_server.py", line 133, in handle
handler.run(self.server.get_app())
File "/usr/lib/python3.4/wsgiref/handlers.py", line 144, in run
self.close()
File "/usr/lib/python3.4/wsgiref/simple_server.py", line 35, in close
self.status.split(' ',1)[0], self.bytes_sent
AttributeError: 'NoneType' object has no attribute 'split'
This output doesn't actually include the script I am running, which I am confused about. Any thoughts?

Just to register the solution for this issue, the problem is with len() function.
str(len(body))
It calculate the wrong size and when return the server Content-Length, then it wait more bytes that needed.
Thus, always send bytes using a buffer with UTF-8, follow example:
from io import StringIO
stdout = StringIO()
print("Hello world!", file=stdout)
start_response("200 OK", [('Content-Type', 'text/plain; charset=utf-8')])
return [stdout.getvalue().encode("utf-8")]

Looking at your code I don't see a direct reason for this error. However, I would strongly advise that unless you're trying to learn how wsgi works (or implement your own framework), you should use an existing micro-framework. WSGI is NOT meant to be used directly by applications. It provides a very thin interface between Python and a web server.
A nice and light framework is bottle.py -- I use it for all Python webapps. But there are many many others, look for "Non Full-Stack Frameworks" in https://wiki.python.org/moin/WebFrameworks.
A nice advantage of bottle is that it's a single file, which makes it easy to distribute with your server.

web connection with python

I have this code to create a webapp in my server:
import web
urls = (
'/update', 'Update',
)
app = web.application(urls, globals())
class Update:
print "hola"
if __name__=='__main__':
app.run()
When I try to execute:
python#ubuntu:~$ python prueba.py 8081
hola
http://0.0.0.0:8081/
Traceback (most recent call last):
File "prueba.py", line 21, in <module>
app.run()
File "/usr/local/lib/python2.6/dist-packages/web/application.py", line 311, in run
return wsgi.runwsgi(self.wsgifunc(*middleware))
File "/usr/local/lib/python2.6/dist-packages/web/wsgi.py", line 54, in runwsgi
return httpserver.runsimple(func, validip(listget(sys.argv, 1, '')))
File "/usr/local/lib/python2.6/dist-packages/web/httpserver.py", line 148, in runsimple
server.start()
File "/usr/local/lib/python2.6/dist-packages/web/wsgiserver/__init__.py", line 1753, in start
raise socket.error(msg)
socket.error: No socket could be created
Why is it happening?
Thank you in advance

The error message says that it couldn't create a listening socket on the specified port. Check if there is already a server running on port 8081.

Python suds Exchange Web Service getting empty service attribute

I finally got my EWS client to not give me 401 errors but I don't know if that actually means anything. Now when I instantiate the suds Client object, it's got an empty service attribute.
from suds.transport.https import *
from suds.client import Client
from os import environ
import sys
def first(car=None, *cdr):
return car
def cleaned(lines):
return map(str.strip, lines)
def getauth(f=open("%s/.ews/auth"%(environ.get("HOME")), "rt")):
return first(cleaned(f.readlines()), f.close())
def serviceURI():
return "https://%s/ews/Services.wsdl"%(environ.get("WEBMAIL"))
def auth():
def nclnt(tx):
return Client(serviceURI(), transport=tx)
def ntauth(username, password):
'''Authenticate with NTLM and return the Client object.'''
return nclnt(WindowsHttpAuthenticated(username=username,
password=password))
def webauth(username, password):
'''Use standard web authentication.'''
return nclnt(HttpAuthenticated(username=username,
password=password))
def authWith(method):
return method(*getauth())
return authWith(ntauth if "ntlm" in sys.argv else webauth)
def main():
def _go(client):
print client
print client.last_received
print dir(client.service)
return 0
return _go(auth())
if __name__=="__main__":
main()
And when I run this:
[ishpeck#slcyoshimitsu random_scripts]$ python ews.py ntlm
Suds ( https://fedorahosted.org/suds/ ) version: 0.4 GA build: R699-20100913
<bound method Client.last_received of <suds.client.Client object at 0x17ea6d0>>
Traceback (most recent call last):
File "ews.py", line 42, in <module>
main()
File "ews.py", line 39, in main
return _go(auth())
File "ews.py", line 37, in _go
print dir(client.service)
File "/usr/lib/python2.7/site-packages/suds/client.py", line 296, in __getattr__
port = self.__find(0)
File "/usr/lib/python2.7/site-packages/suds/client.py", line 331, in __find
raise Exception, 'No services defined'
Exception: No services defined
[ishpeck#slcyoshimitsu random_scripts]$ python ews.py
Suds ( https://fedorahosted.org/suds/ ) version: 0.4 GA build: R699-20100913
<bound method Client.last_received of <suds.client.Client object at 0x136c6d0>>
Traceback (most recent call last):
File "ews.py", line 42, in <module>
main()
File "ews.py", line 39, in main
return _go(auth())
File "ews.py", line 37, in _go
print dir(client.service)
File "/usr/lib/python2.7/site-packages/suds/client.py", line 296, in __getattr__
port = self.__find(0)
File "/usr/lib/python2.7/site-packages/suds/client.py", line 331, in __find
raise Exception, 'No services defined'
Exception: No services defined
I'm noticing a lot of people complaining about having problems with this very thing but haven't found anybody who claims to have gotten it working.

your "print client" line didn't return anything, so I suspect it had a problem with the wsdl.
Turn on some debugging to see what's going on..
import logging
logging.basicConfig(level=logging.DEBUG, filename="suds.log")
logging.getLogger('suds.client').setLevel(logging.DEBUG)
logging.getLogger('suds.transport').setLevel(logging.DEBUG)
logging.getLogger('suds.xsd.schema').setLevel(logging.DEBUG)
logging.getLogger('suds.wsdl').setLevel(logging.DEBUG)