view sat/plugins/plugin_adhoc_dbus.py @ 2646:712cb4ff3e13

core: new EncryptionHandler class which manage encrypted session as a core feature: Plugin handling encryption can now register using host.registerEncryptionPlugin, and an encryption session can now be started using messageEncryptionStart bridge method. This will make encryption handling more easy, as we now know if a session is clear or e2e encrypted, and which plugin handle it.
author Goffi <goffi@goffi.org>
date Sun, 29 Jul 2018 19:22:56 +0200
parents 56f94936df1e
children 8dd9db785ac8
line wrap: on
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#!/usr/bin/env python2
# -*- coding: utf-8 -*-

# SAT plugin for adding D-Bus to Ad-Hoc Commands
# Copyright (C) 2009-2018 Jérôme Poisson (goffi@goffi.org)

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero 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 Affero General Public License for more details.

# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

from sat.core.i18n import _
from sat.core.constants import Const as C
from sat.core.log import getLogger

log = getLogger(__name__)
from sat.core import exceptions
from twisted.internet import defer
from wokkel import data_form

try:
    from lxml import etree
except ImportError:
    raise exceptions.MissingModule(
        u"Missing module lxml, please download/install it from http://lxml.de/"
    )
import os.path
import uuid
import dbus
from dbus.mainloop.glib import DBusGMainLoop

DBusGMainLoop(set_as_default=True)

FD_NAME = "org.freedesktop.DBus"
FD_PATH = "/org/freedekstop/DBus"
INTROSPECT_IFACE = "org.freedesktop.DBus.Introspectable"

INTROSPECT_METHOD = "Introspect"
IGNORED_IFACES_START = (
    "org.freedesktop",
    "org.qtproject",
    "org.kde.KMainWindow",
)  # commands in interface starting with these values will be ignored
FLAG_LOOP = "LOOP"

PLUGIN_INFO = {
    C.PI_NAME: "Ad-Hoc Commands - D-Bus",
    C.PI_IMPORT_NAME: "AD_HOC_DBUS",
    C.PI_TYPE: "Misc",
    C.PI_PROTOCOLS: [],
    C.PI_DEPENDENCIES: ["XEP-0050"],
    C.PI_MAIN: "AdHocDBus",
    C.PI_HANDLER: "no",
    C.PI_DESCRIPTION: _("""Add D-Bus management to Ad-Hoc commands"""),
}


class AdHocDBus(object):
    def __init__(self, host):
        log.info(_("plugin Ad-Hoc D-Bus initialization"))
        self.host = host
        host.bridge.addMethod(
            "adHocDBusAddAuto",
            ".plugin",
            in_sign="sasasasasasass",
            out_sign="(sa(sss))",
            method=self._adHocDBusAddAuto,
            async=True,
        )
        self.session_bus = dbus.SessionBus()
        self.fd_object = self.session_bus.get_object(FD_NAME, FD_PATH, introspect=False)
        self.XEP_0050 = host.plugins["XEP-0050"]

    def _DBusAsyncCall(self, proxy, method, *args, **kwargs):
        """ Call a DBus method asynchronously and return a deferred
        @param proxy: DBus object proxy, as returner by get_object
        @param method: name of the method to call
        @param args: will be transmitted to the method
        @param kwargs: will be transmetted to the method, except for the following poped values:
                       - interface: name of the interface to use
        @return: a deferred

        """
        d = defer.Deferred()
        interface = kwargs.pop("interface", None)
        kwargs["reply_handler"] = lambda ret=None: d.callback(ret)
        kwargs["error_handler"] = d.errback
        proxy.get_dbus_method(method, dbus_interface=interface)(*args, **kwargs)
        return d

    def _DBusListNames(self):
        return self._DBusAsyncCall(self.fd_object, "ListNames")

    def _DBusIntrospect(self, proxy):
        return self._DBusAsyncCall(proxy, INTROSPECT_METHOD, interface=INTROSPECT_IFACE)

    def _acceptMethod(self, method):
        """ Return True if we accept the method for a command
        @param method: etree.Element
        @return: True if the method is acceptable

        """
        if method.xpath(
            "arg[@direction='in']"
        ):  # we don't accept method with argument for the moment
            return False
        return True

    @defer.inlineCallbacks
    def _introspect(self, methods, bus_name, proxy):
        log.debug("introspecting path [%s]" % proxy.object_path)
        introspect_xml = yield self._DBusIntrospect(proxy)
        el = etree.fromstring(introspect_xml)
        for node in el.iterchildren("node", "interface"):
            if node.tag == "node":
                new_path = os.path.join(proxy.object_path, node.get("name"))
                new_proxy = self.session_bus.get_object(
                    bus_name, new_path, introspect=False
                )
                yield self._introspect(methods, bus_name, new_proxy)
            elif node.tag == "interface":
                name = node.get("name")
                if any(name.startswith(ignored) for ignored in IGNORED_IFACES_START):
                    log.debug("interface [%s] is ignored" % name)
                    continue
                log.debug("introspecting interface [%s]" % name)
                for method in node.iterchildren("method"):
                    if self._acceptMethod(method):
                        method_name = method.get("name")
                        log.debug("method accepted: [%s]" % method_name)
                        methods.add((proxy.object_path, name, method_name))

    def _adHocDBusAddAuto(
        self,
        prog_name,
        allowed_jids,
        allowed_groups,
        allowed_magics,
        forbidden_jids,
        forbidden_groups,
        flags,
        profile_key,
    ):
        return self.adHocDBusAddAuto(
            prog_name,
            allowed_jids,
            allowed_groups,
            allowed_magics,
            forbidden_jids,
            forbidden_groups,
            flags,
            profile_key,
        )

    @defer.inlineCallbacks
    def adHocDBusAddAuto(
        self,
        prog_name,
        allowed_jids=None,
        allowed_groups=None,
        allowed_magics=None,
        forbidden_jids=None,
        forbidden_groups=None,
        flags=None,
        profile_key=C.PROF_KEY_NONE,
    ):
        bus_names = yield self._DBusListNames()
        bus_names = [bus_name for bus_name in bus_names if "." + prog_name in bus_name]
        if not bus_names:
            log.info("Can't find any bus for [%s]" % prog_name)
            defer.returnValue(("", []))
        bus_names.sort()
        for bus_name in bus_names:
            if bus_name.endswith(prog_name):
                break
        log.info("bus name found: [%s]" % bus_name)
        proxy = self.session_bus.get_object(bus_name, "/", introspect=False)
        methods = set()

        yield self._introspect(methods, bus_name, proxy)

        if methods:
            self._addCommand(
                prog_name,
                bus_name,
                methods,
                allowed_jids=allowed_jids,
                allowed_groups=allowed_groups,
                allowed_magics=allowed_magics,
                forbidden_jids=forbidden_jids,
                forbidden_groups=forbidden_groups,
                flags=flags,
                profile_key=profile_key,
            )

        defer.returnValue((bus_name, methods))

    def _addCommand(
        self,
        adhoc_name,
        bus_name,
        methods,
        allowed_jids=None,
        allowed_groups=None,
        allowed_magics=None,
        forbidden_jids=None,
        forbidden_groups=None,
        flags=None,
        profile_key=C.PROF_KEY_NONE,
    ):
        if flags is None:
            flags = set()

        def DBusCallback(command_elt, session_data, action, node, profile):
            actions = session_data.setdefault("actions", [])
            names_map = session_data.setdefault("names_map", {})
            actions.append(action)

            if len(actions) == 1:
                # it's our first request, we ask the desired new status
                status = self.XEP_0050.STATUS.EXECUTING
                form = data_form.Form("form", title=_("Command selection"))
                options = []
                for path, iface, command in methods:
                    label = command.rsplit(".", 1)[-1]
                    name = str(uuid.uuid4())
                    names_map[name] = (path, iface, command)
                    options.append(data_form.Option(name, label))

                field = data_form.Field(
                    "list-single", "command", options=options, required=True
                )
                form.addField(field)

                payload = form.toElement()
                note = None

            elif len(actions) == 2:
                # we should have the answer here
                try:
                    x_elt = command_elt.elements(data_form.NS_X_DATA, "x").next()
                    answer_form = data_form.Form.fromElement(x_elt)
                    command = answer_form["command"]
                except (KeyError, StopIteration):
                    raise self.XEP_0050.AdHocError(self.XEP_0050.ERROR.BAD_PAYLOAD)

                if command not in names_map:
                    raise self.XEP_0050.AdHocError(self.XEP_0050.ERROR.BAD_PAYLOAD)

                path, iface, command = names_map[command]
                proxy = self.session_bus.get_object(bus_name, path)

                self._DBusAsyncCall(proxy, command, interface=iface)

                # job done, we can end the session, except if we have FLAG_LOOP
                if FLAG_LOOP in flags:
                    # We have a loop, so we clear everything and we execute again the command as we had a first call (command_elt is not used, so None is OK)
                    del actions[:]
                    names_map.clear()
                    return DBusCallback(
                        None, session_data, self.XEP_0050.ACTION.EXECUTE, node, profile
                    )
                form = data_form.Form("form", title=_(u"Updated"))
                form.addField(data_form.Field("fixed", u"Command sent"))
                status = self.XEP_0050.STATUS.COMPLETED
                payload = None
                note = (self.XEP_0050.NOTE.INFO, _(u"Command sent"))
            else:
                raise self.XEP_0050.AdHocError(self.XEP_0050.ERROR.INTERNAL)

            return (payload, status, None, note)

        self.XEP_0050.addAdHocCommand(
            DBusCallback,
            adhoc_name,
            allowed_jids=allowed_jids,
            allowed_groups=allowed_groups,
            allowed_magics=allowed_magics,
            forbidden_jids=forbidden_jids,
            forbidden_groups=forbidden_groups,
            profile_key=profile_key,
        )