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Diffstat (limited to 'src/leap/bitmask/backend.py')
| -rw-r--r-- | src/leap/bitmask/backend.py | 381 |
1 files changed, 381 insertions, 0 deletions
diff --git a/src/leap/bitmask/backend.py b/src/leap/bitmask/backend.py new file mode 100644 index 00000000..8a289a79 --- /dev/null +++ b/src/leap/bitmask/backend.py @@ -0,0 +1,381 @@ +# -*- coding: utf-8 -*- +# backend.py +# Copyright (C) 2013 LEAP +# +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation, either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. +""" +Backend for everything +""" +import logging +import os + +from Queue import Queue, Empty + +from twisted.internet import threads, defer +from twisted.internet.task import LoopingCall +from twisted.python import log + +import zope.interface + +from leap.bitmask.config.providerconfig import ProviderConfig +from leap.bitmask.provider.providerbootstrapper import ProviderBootstrapper + +# Frontend side +from PySide import QtCore + +logger = logging.getLogger(__name__) + + +class ILEAPComponent(zope.interface.Interface): + """ + Interface that every component for the backend should comply to + """ + + key = zope.interface.Attribute("Key id for this component") + + +class ILEAPService(ILEAPComponent): + """ + Interface that every Service needs to implement + """ + + def start(self): + """ + Starts the service. + """ + pass + + def stop(self): + """ + Stops the service. + """ + pass + + def terminate(self): + """ + Terminates the service, not necessarily in a nice way. + """ + pass + + def status(self): + """ + Returns a json object with the current status for the service. + + :rtype: object (list, str, dict) + """ + # XXX: Use a namedtuple or a specific object instead of a json + # object, since parsing it will be problematic otherwise. + # It has to be something easily serializable though. + pass + + def set_configs(self, keyval): + """ + Sets the config parameters for this Service. + + :param keyval: values to configure + :type keyval: dict, {str: str} + """ + pass + + def get_configs(self, keys): + """ + Returns the configuration values for the list of keys. + + :param keys: keys to retrieve + :type keys: list of str + + :rtype: dict, {str: str} + """ + pass + + +class Provider(object): + """ + Interfaces with setup and bootstrapping operations for a provider + """ + + zope.interface.implements(ILEAPComponent) + + PROBLEM_SIGNAL = "prov_problem_with_provider" + + def __init__(self, signaler=None, bypass_checks=False): + """ + Constructor for the Provider component + + :param signaler: Object in charge of handling communication + back to the frontend + :type signaler: Signaler + :param bypass_checks: Set to true if the app should bypass + first round of checks for CA + certificates at bootstrap + :type bypass_checks: bool + """ + object.__init__(self) + self.key = "provider" + self._provider_bootstrapper = ProviderBootstrapper(signaler, + bypass_checks) + self._download_provider_defer = None + self._provider_config = ProviderConfig() + + def setup_provider(self, provider): + """ + Initiates the setup for a provider + + :param provider: URL for the provider + :type provider: unicode + """ + log.msg("Setting up provider %s..." % (provider.encode("idna"),)) + pb = self._provider_bootstrapper + d = pb.run_provider_select_checks(provider, download_if_needed=True) + self._download_provider_defer = d + return d + + def bootstrap(self, provider): + """ + Second stage of bootstrapping for a provider. + + :param provider: URL for the provider + :type provider: unicode + """ + + d = None + + # If there's no loaded provider or + # we want to connect to other provider... + if (not self._provider_config.loaded() or + self._provider_config.get_domain() != provider): + self._provider_config.load( + os.path.join("leap", "providers", + provider, "provider.json")) + + if self._provider_config.loaded(): + d = self._provider_bootstrapper.run_provider_setup_checks( + self._provider_config, + download_if_needed=True) + else: + if self._signaler is not None: + self._signaler.signal(self.PROBLEM_SIGNAL) + logger.error("Could not load provider configuration.") + self._login_widget.set_enabled(True) + + if d is None: + d = defer.Deferred() + return d + + +class Signaler(QtCore.QObject): + """ + Signaler object, handles converting string commands to Qt signals. + + This is intended for the separation in frontend/backend, this will + live in the frontend. + """ + + # Signals for the ProviderBootstrapper + # These will only exist in the frontend + prov_name_resolution = QtCore.Signal(object) + prov_https_connection = QtCore.Signal(object) + prov_download_provider_info = QtCore.Signal(object) + + prov_download_ca_cert = QtCore.Signal(object) + prov_check_ca_fingerprint = QtCore.Signal(object) + prov_check_api_certificate = QtCore.Signal(object) + + prov_problem_with_provider = QtCore.Signal(object) + + # These will exist both in the backend and the front end. + # The frontend might choose to not "interpret" all the signals + # from the backend, but the backend needs to have all the signals + # it's going to emit defined here + PROV_NAME_RESOLUTION_KEY = "prov_name_resolution" + PROV_HTTPS_CONNECTION_KEY = "prov_https_connection" + PROV_DOWNLOAD_PROVIDER_INFO_KEY = "prov_download_provider_info" + PROV_DOWNLOAD_CA_CERT_KEY = "prov_download_ca_cert" + PROV_CHECK_CA_FINGERPRINT_KEY = "prov_check_ca_fingerprint" + PROV_CHECK_API_CERTIFICATE_KEY = "prov_check_api_certificate" + PROV_PROV_PROBLEM_WITH_PROVIER_KEY = "prov_problem_with_provider" + + def __init__(self): + """ + Constructor for the Signaler + """ + QtCore.QObject.__init__(self) + self._signals = {} + + signals = [ + self.PROV_NAME_RESOLUTION_KEY, + self.PROV_HTTPS_CONNECTION_KEY, + self.PROV_DOWNLOAD_PROVIDER_INFO_KEY, + self.PROV_DOWNLOAD_CA_CERT_KEY, + self.PROV_CHECK_CA_FINGERPRINT_KEY, + self.PROV_CHECK_API_CERTIFICATE_KEY, + self.PROV_PROV_PROBLEM_WITH_PROVIER_KEY + ] + + for sig in signals: + self._signals[sig] = getattr(self, sig) + + def signal(self, key, data=None): + """ + Emits a Qt signal based on the key provided, with the data if provided. + + :param key: string identifying the signal to emit + :type key: str + :param data: object to send with the data + :type data: object + + NOTE: The data object will be a serialized str in the backend, + and an unserialized object in the frontend, but for now we + just care about objects. + """ + # Right now it emits Qt signals. The backend version of this + # will do zmq.send_multipart, and the frontend version will be + # similar to this + log.msg("Signaling %s :: %s" % (key, data)) + try: + self._signals[key].emit(data) + except KeyError: + log.msg("Unknown key for signal %s!" % (key,)) + + +class Backend(object): + """ + Backend for everything, the UI should only use this class. + """ + + PASSED_KEY = "passed" + ERROR_KEY = "error" + + def __init__(self, bypass_checks=False): + """ + Constructor for the backend. + """ + object.__init__(self) + + # Components map for the commands received + self._components = {} + + # Ongoing defers that will be cancelled at stop time + self._ongoing_defers = [] + + # Signaler object to translate commands into Qt signals + self._signaler = Signaler() + + # Component registration + self._register(Provider(self._signaler, bypass_checks)) + + # We have a looping call on a thread executing all the + # commands in queue. Right now this queue is an actual Queue + # object, but it'll become the zmq recv_multipart queue + self._lc = LoopingCall(threads.deferToThread, self._worker) + + # Temporal call_queue for worker, will be replaced with + # recv_multipart os something equivalent in the loopingcall + self._call_queue = Queue() + + @property + def signaler(self): + """ + Public signaler access to let the UI connect to its signals. + """ + return self._signaler + + def start(self): + """ + Starts the looping call + """ + log.msg("Starting worker...") + self._lc.start(0.01) + + def stop(self): + """ + Stops the looping call and tries to cancel all the defers. + """ + log.msg("Stopping worker...") + self._lc.stop() + while len(self._ongoing_defers) > 0: + d = self._ongoing_defers.pop() + d.cancel() + + def _register(self, component): + """ + Registers a component in this backend + + :param component: Component to register + :type component: any object that implements ILEAPComponent + """ + # TODO: assert that the component implements the interfaces + # expected + try: + self._components[component.key] = component + except Exception: + log.msg("There was a problem registering %s" % (component,)) + log.err() + + def _signal_back(self, _, signal): + """ + Helper method to signal back (callback like behavior) to the + UI that an operation finished. + + :param signal: signal name + :type signal: str + """ + self._signaler.signal(signal) + + def _worker(self): + """ + Worker method, called from a different thread and as a part of + a looping call + """ + try: + # this'll become recv_multipart + cmd = self._call_queue.get(block=False) + + # cmd is: component, method, signalback, *args + func = getattr(self._components[cmd[0]], cmd[1]) + d = func(*cmd[3:]) + # A call might not have a callback signal, but if it does, + # we add it to the chain + if cmd[2] is not None: + d.addCallbacks(self._signal_back, log.err, cmd[2]) + d.addCallbacks(self._done_action, log.err, + callbackKeywords={"d": d}) + d.addErrback(log.err) + self._ongoing_defers.append(d) + except Empty: + # If it's just empty we don't have anything to do. + pass + except Exception: + # But we log the rest + log.err() + + def _done_action(self, _, d): + """ + Remover of the defer once it's done + + :param d: defer to remove + :type d: twisted.internet.defer.Deferred + """ + self._ongoing_defers.remove(d) + + # XXX: Temporal interface until we migrate to zmq + # We simulate the calls to zmq.send_multipart. Once we separate + # this in two processes, the methods bellow can be changed to + # send_multipart and this backend class will be really simple. + + def setup_provider(self, provider): + self._call_queue.put(("provider", "setup_provider", None, provider)) + + def provider_bootstrap(self, provider): + self._call_queue.put(("provider", "bootstrap", None, provider)) |