/mandos/trunk

#!/usr/bin/python

# -*- mode: python; coding: utf-8 -*-

# 

# Mandos Monitor - Control and monitor the Mandos server

# 

# Copyright © 2009-2012 Teddy Hogeborn

# Copyright © 2009-2012 Björn Påhlsson

# 

# 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/>.

# 

# Contact the authors at <mandos@recompile.se>.

# 

from __future__ import (division, absolute_import, print_function,

                        unicode_literals)

from future_builtins import *

import sys

import os

import signal

import datetime

import urwid.curses_display

import urwid

from dbus.mainloop.glib import DBusGMainLoop

import gobject

import dbus

import UserList

import locale

locale.setlocale(locale.LC_ALL, '')

import logging

logging.getLogger('dbus.proxies').setLevel(logging.CRITICAL)

# Some useful constants

domain = 'se.recompile'

server_interface = domain + '.Mandos'

client_interface = domain + '.Mandos.Client'

version = "1.6.0"

# Always run in monochrome mode

urwid.curses_display.curses.has_colors = lambda : False

# Urwid doesn't support blinking, but we want it.  Since we have no

# use for underline on its own, we make underline also always blink.

urwid.curses_display.curses.A_UNDERLINE |= (

    urwid.curses_display.curses.A_BLINK)

def isoformat_to_datetime(iso):

    "Parse an ISO 8601 date string to a datetime.datetime()"

    if not iso:

        return None

    d, t = iso.split("T", 1)

    year, month, day = d.split("-", 2)

    hour, minute, second = t.split(":", 2)

    second, fraction = divmod(float(second), 1)

    return datetime.datetime(int(year),

                             int(month),

                             int(day),

                             int(hour),

                             int(minute),

                             int(second),           # Whole seconds

                             int(fraction*1000000)) # Microseconds

class MandosClientPropertyCache(object):

    """This wraps a Mandos Client D-Bus proxy object, caches the

    properties and calls a hook function when any of them are

    changed.

    """

    def __init__(self, proxy_object=None, properties=None, **kwargs):

        self.proxy = proxy_object # Mandos Client proxy object

        self.properties = dict() if properties is None else properties

        self.property_changed_match = (

            self.proxy.connect_to_signal("PropertyChanged",

                                         self._property_changed,

                                         client_interface,

                                         byte_arrays=True))

        if properties is None:

            self.properties.update(

                self.proxy.GetAll(client_interface,

                                  dbus_interface

                                  = dbus.PROPERTIES_IFACE))

        super(MandosClientPropertyCache, self).__init__(**kwargs)

    def _property_changed(self, property, value):

        """Helper which takes positional arguments"""

        return self.property_changed(property=property, value=value)

    def property_changed(self, property=None, value=None):

        """This is called whenever we get a PropertyChanged signal

        It updates the changed property in the "properties" dict.

        """

        # Update properties dict with new value

        self.properties[property] = value

    def delete(self):

        self.property_changed_match.remove()

class MandosClientWidget(urwid.FlowWidget, MandosClientPropertyCache):

    """A Mandos Client which is visible on the screen.

    """

    def __init__(self, server_proxy_object=None, update_hook=None,

                 delete_hook=None, logger=None, **kwargs):

        # Called on update

        self.update_hook = update_hook

        # Called on delete

        self.delete_hook = delete_hook

        # Mandos Server proxy object

        self.server_proxy_object = server_proxy_object

        # Logger

        self.logger = logger

        self._update_timer_callback_tag = None

        # The widget shown normally

        self._text_widget = urwid.Text("")

        # The widget shown when we have focus

        self._focus_text_widget = urwid.Text("")

        super(MandosClientWidget, self).__init__(**kwargs)

        self.update()

        self.opened = False

        self.match_objects = (

            self.proxy.connect_to_signal("CheckerCompleted",

                                         self.checker_completed,

                                         client_interface,

                                         byte_arrays=True),

            self.proxy.connect_to_signal("CheckerStarted",

                                         self.checker_started,

                                         client_interface,

                                         byte_arrays=True),

            self.proxy.connect_to_signal("GotSecret",

                                         self.got_secret,

                                         client_interface,

                                         byte_arrays=True),

            self.proxy.connect_to_signal("NeedApproval",

                                         self.need_approval,

                                         client_interface,

                                         byte_arrays=True),

            self.proxy.connect_to_signal("Rejected",

                                         self.rejected,

                                         client_interface,

                                         byte_arrays=True))

        #self.logger('Created client {0}'

        #            .format(self.properties["Name"]))

    def using_timer(self, flag):

        """Call this method with True or False when timer should be

        activated or deactivated.

        """

        if flag and self._update_timer_callback_tag is None:

            # Will update the shown timer value every second

            self._update_timer_callback_tag = (gobject.timeout_add

                                               (1000,

                                                self.update_timer))

        elif not (flag or self._update_timer_callback_tag is None):

            gobject.source_remove(self._update_timer_callback_tag)

            self._update_timer_callback_tag = None

    def checker_completed(self, exitstatus, condition, command):

        if exitstatus == 0:

            self.update()

            return

        # Checker failed

        if os.WIFEXITED(condition):

            self.logger('Checker for client {0} (command "{1}")'

                        ' failed with exit code {2}'

                        .format(self.properties["Name"], command,

                                os.WEXITSTATUS(condition)))

        elif os.WIFSIGNALED(condition):

            self.logger('Checker for client {0} (command "{1}") was'

                        ' killed by signal {2}'

                        .format(self.properties["Name"], command,

                                os.WTERMSIG(condition)))

        elif os.WCOREDUMP(condition):

            self.logger('Checker for client {0} (command "{1}")'

                        ' dumped core'

                        .format(self.properties["Name"], command))

        else:

            self.logger('Checker for client {0} completed'

                        ' mysteriously'

                        .format(self.properties["Name"]))

        self.update()

    def checker_started(self, command):

        """Server signals that a checker started. This could be useful

           to log in the future. """

        #self.logger('Client {0} started checker "{1}"'

        #            .format(self.properties["Name"],

        #                    unicode(command)))

        pass

    def got_secret(self):

        self.logger('Client {0} received its secret'

                    .format(self.properties["Name"]))

    def need_approval(self, timeout, default):

        if not default:

            message = 'Client {0} needs approval within {1} seconds'

        else:

            message = 'Client {0} will get its secret in {1} seconds'

        self.logger(message.format(self.properties["Name"],

                                   timeout/1000))

    def rejected(self, reason):

        self.logger('Client {0} was rejected; reason: {1}'

                    .format(self.properties["Name"], reason))

    def selectable(self):

        """Make this a "selectable" widget.

        This overrides the method from urwid.FlowWidget."""

        return True

    def rows(self, maxcolrow, focus=False):

        """How many rows this widget will occupy might depend on

        whether we have focus or not.

        This overrides the method from urwid.FlowWidget"""

        return self.current_widget(focus).rows(maxcolrow, focus=focus)

    def current_widget(self, focus=False):

        if focus or self.opened:

            return self._focus_widget

        return self._widget

    def update(self):

        "Called when what is visible on the screen should be updated."

        # How to add standout mode to a style

        with_standout = { "normal": "standout",

                          "bold": "bold-standout",

                          "underline-blink":

                              "underline-blink-standout",

                          "bold-underline-blink":

                              "bold-underline-blink-standout",

                          }

        # Rebuild focus and non-focus widgets using current properties

        # Base part of a client. Name!

        base = '{name}: '.format(name=self.properties["Name"])

        if not self.properties["Enabled"]:

            message = "DISABLED"

            self.using_timer(False)

        elif self.properties["ApprovalPending"]:

            timeout = datetime.timedelta(milliseconds

                                         = self.properties

                                         ["ApprovalDelay"])

            last_approval_request = isoformat_to_datetime(

                self.properties["LastApprovalRequest"])

            if last_approval_request is not None:

                timer = max(timeout - (datetime.datetime.utcnow()

                                       - last_approval_request),

                            datetime.timedelta())

            else:

                timer = datetime.timedelta()

            if self.properties["ApprovedByDefault"]:

                message = "Approval in {0}. (d)eny?"

            else:

                message = "Denial in {0}. (a)pprove?"

            message = message.format(unicode(timer).rsplit(".", 1)[0])

            self.using_timer(True)

        elif self.properties["LastCheckerStatus"] != 0:

            # When checker has failed, show timer until client expires

            expires = self.properties["Expires"]

            if expires == "":

                timer = datetime.timedelta(0)

            else:

                expires = (datetime.datetime.strptime

                           (expires, '%Y-%m-%dT%H:%M:%S.%f'))

                timer = max(expires - datetime.datetime.utcnow(),

                            datetime.timedelta())

            message = ('A checker has failed! Time until client'

                       ' gets disabled: {0}'

                       .format(unicode(timer).rsplit(".", 1)[0]))

            self.using_timer(True)

        else:

            message = "enabled"

            self.using_timer(False)

        self._text = "{0}{1}".format(base, message)

        if not urwid.supports_unicode():

            self._text = self._text.encode("ascii", "replace")

        textlist = [("normal", self._text)]

        self._text_widget.set_text(textlist)

        self._focus_text_widget.set_text([(with_standout[text[0]],

                                           text[1])

                                          if isinstance(text, tuple)

                                          else text

                                          for text in textlist])

        self._widget = self._text_widget

        self._focus_widget = urwid.AttrWrap(self._focus_text_widget,

                                            "standout")

        # Run update hook, if any

        if self.update_hook is not None:

            self.update_hook()

    def update_timer(self):

        """called by gobject. Will indefinitely loop until

        gobject.source_remove() on tag is called"""

        self.update()

        return True             # Keep calling this

    def delete(self, **kwargs):

        if self._update_timer_callback_tag is not None:

            gobject.source_remove(self._update_timer_callback_tag)

            self._update_timer_callback_tag = None

        for match in self.match_objects:

            match.remove()

        self.match_objects = ()

        if self.delete_hook is not None:

            self.delete_hook(self)

        return super(MandosClientWidget, self).delete(**kwargs)

    def render(self, maxcolrow, focus=False):

        """Render differently if we have focus.

        This overrides the method from urwid.FlowWidget"""

        return self.current_widget(focus).render(maxcolrow,

                                                 focus=focus)

    def keypress(self, maxcolrow, key):

        """Handle keys.

        This overrides the method from urwid.FlowWidget"""

        if key == "+":

            self.proxy.Enable(dbus_interface = client_interface,

                              ignore_reply=True)

        elif key == "-":

            self.proxy.Disable(dbus_interface = client_interface,

                               ignore_reply=True)

        elif key == "a":

            self.proxy.Approve(dbus.Boolean(True, variant_level=1),

                               dbus_interface = client_interface,

                               ignore_reply=True)

        elif key == "d":

            self.proxy.Approve(dbus.Boolean(False, variant_level=1),

                                  dbus_interface = client_interface,

                               ignore_reply=True)

        elif key == "R" or key == "_" or key == "ctrl k":

            self.server_proxy_object.RemoveClient(self.proxy

                                                  .object_path,

                                                  ignore_reply=True)

        elif key == "s":

            self.proxy.StartChecker(dbus_interface = client_interface,

                                    ignore_reply=True)

        elif key == "S":

            self.proxy.StopChecker(dbus_interface = client_interface,

                                   ignore_reply=True)

        elif key == "C":

            self.proxy.CheckedOK(dbus_interface = client_interface,

                                 ignore_reply=True)

        # xxx

#         elif key == "p" or key == "=":

#             self.proxy.pause()

#         elif key == "u" or key == ":":

#             self.proxy.unpause()

#         elif key == "RET":

#             self.open()

        else:

            return key

    def property_changed(self, property=None, **kwargs):

        """Call self.update() if old value is not new value.

        This overrides the method from MandosClientPropertyCache"""

        property_name = unicode(property)

        old_value = self.properties.get(property_name)

        super(MandosClientWidget, self).property_changed(

            property=property, **kwargs)

        if self.properties.get(property_name) != old_value:

            self.update()

class ConstrainedListBox(urwid.ListBox):

    """Like a normal urwid.ListBox, but will consume all "up" or

    "down" key presses, thus not allowing any containing widgets to

    use them as an excuse to shift focus away from this widget.

    """

    def keypress(self, *args, **kwargs):

        ret = super(ConstrainedListBox, self).keypress(*args, **kwargs)

        if ret in ("up", "down"):

            return

        return ret

class UserInterface(object):

    """This is the entire user interface - the whole screen

    with boxes, lists of client widgets, etc.

    """

    def __init__(self, max_log_length=1000):

        DBusGMainLoop(set_as_default=True)

        self.screen = urwid.curses_display.Screen()

        self.screen.register_palette((

                ("normal",

                 "default", "default", None),

                ("bold",

                 "default", "default", "bold"),

                ("underline-blink",

                 "default", "default", "underline"),

                ("standout",

                 "default", "default", "standout"),

                ("bold-underline-blink",

                 "default", "default", ("bold", "underline")),

                ("bold-standout",

                 "default", "default", ("bold", "standout")),

                ("underline-blink-standout",

                 "default", "default", ("underline", "standout")),

                ("bold-underline-blink-standout",

                 "default", "default", ("bold", "underline",

                                          "standout")),

                ))

        if urwid.supports_unicode():

            self.divider = "─" # \u2500

            #self.divider = "━" # \u2501

        else:

            #self.divider = "-" # \u002d

            self.divider = "_" # \u005f

        self.screen.start()

        self.size = self.screen.get_cols_rows()

        self.clients = urwid.SimpleListWalker([])

        self.clients_dict = {}

        # We will add Text widgets to this list

        self.log = []

        self.max_log_length = max_log_length

        # We keep a reference to the log widget so we can remove it

        # from the ListWalker without it getting destroyed

        self.logbox = ConstrainedListBox(self.log)

        # This keeps track of whether self.uilist currently has

        # self.logbox in it or not

        self.log_visible = True

        self.log_wrap = "any"

        self.rebuild()

        self.log_message_raw(("bold",

                              "Mandos Monitor version " + version))

        self.log_message_raw(("bold",

                              "q: Quit  ?: Help"))

        self.busname = domain + '.Mandos'

        self.main_loop = gobject.MainLoop()

    def client_not_found(self, fingerprint, address):

        self.log_message("Client with address {0} and fingerprint"

                         " {1} could not be found"

                         .format(address, fingerprint))

    def rebuild(self):

        """This rebuilds the User Interface.

        Call this when the widget layout needs to change"""

        self.uilist = []

        #self.uilist.append(urwid.ListBox(self.clients))

        self.uilist.append(urwid.Frame(ConstrainedListBox(self.

                                                          clients),

                                       #header=urwid.Divider(),

                                       header=None,

                                       footer=

                                       urwid.Divider(div_char=

                                                     self.divider)))

        if self.log_visible:

            self.uilist.append(self.logbox)

        self.topwidget = urwid.Pile(self.uilist)

    def log_message(self, message):

        timestamp = datetime.datetime.now().isoformat()

        self.log_message_raw(timestamp + ": " + message)

    def log_message_raw(self, markup):

        """Add a log message to the log buffer."""

        self.log.append(urwid.Text(markup, wrap=self.log_wrap))

        if (self.max_log_length

            and len(self.log) > self.max_log_length):

            del self.log[0:len(self.log)-self.max_log_length-1]

        self.logbox.set_focus(len(self.logbox.body.contents),

                              coming_from="above")

        self.refresh()

    def toggle_log_display(self):

        """Toggle visibility of the log buffer."""

        self.log_visible = not self.log_visible

        self.rebuild()

        #self.log_message("Log visibility changed to: "

        #                 + unicode(self.log_visible))

    def change_log_display(self):

        """Change type of log display.

        Currently, this toggles wrapping of text lines."""

        if self.log_wrap == "clip":

            self.log_wrap = "any"

        else:

            self.log_wrap = "clip"

        for textwidget in self.log:

            textwidget.set_wrap_mode(self.log_wrap)

        #self.log_message("Wrap mode: " + self.log_wrap)

    def find_and_remove_client(self, path, name):

        """Find a client by its object path and remove it.

        This is connected to the ClientRemoved signal from the

        Mandos server object."""

        try:

            client = self.clients_dict[path]

        except KeyError:

            # not found?

            self.log_message("Unknown client {0!r} ({1!r}) removed"

                             .format(name, path))

            return

        client.delete()

    def add_new_client(self, path):

        client_proxy_object = self.bus.get_object(self.busname, path)

        self.add_client(MandosClientWidget(server_proxy_object

                                           =self.mandos_serv,

                                           proxy_object

                                           =client_proxy_object,

                                           update_hook

                                           =self.refresh,

                                           delete_hook

                                           =self.remove_client,

                                           logger

                                           =self.log_message),

                        path=path)

    def add_client(self, client, path=None):

        self.clients.append(client)

        if path is None:

            path = client.proxy.object_path

        self.clients_dict[path] = client

        self.clients.sort(None, lambda c: c.properties["Name"])

        self.refresh()

    def remove_client(self, client, path=None):

        self.clients.remove(client)

        if path is None:

            path = client.proxy.object_path

        del self.clients_dict[path]

        if not self.clients_dict:

            # Work around bug in Urwid 0.9.8.3 - if a SimpleListWalker

            # is completely emptied, we need to recreate it.

            self.clients = urwid.SimpleListWalker([])

            self.rebuild()

        self.refresh()

    def refresh(self):

        """Redraw the screen"""

        canvas = self.topwidget.render(self.size, focus=True)

        self.screen.draw_screen(self.size, canvas)

    def run(self):

        """Start the main loop and exit when it's done."""

        self.bus = dbus.SystemBus()

        mandos_dbus_objc = self.bus.get_object(

            self.busname, "/", follow_name_owner_changes=True)

        self.mandos_serv = dbus.Interface(mandos_dbus_objc,

                                          dbus_interface

                                          = server_interface)

        try:

            mandos_clients = (self.mandos_serv

                              .GetAllClientsWithProperties())

        except dbus.exceptions.DBusException:

            mandos_clients = dbus.Dictionary()

        (self.mandos_serv

         .connect_to_signal("ClientRemoved",

                            self.find_and_remove_client,

                            dbus_interface=server_interface,

                            byte_arrays=True))

        (self.mandos_serv

         .connect_to_signal("ClientAdded",

                            self.add_new_client,

                            dbus_interface=server_interface,

                            byte_arrays=True))

        (self.mandos_serv

         .connect_to_signal("ClientNotFound",

                            self.client_not_found,

                            dbus_interface=server_interface,

                            byte_arrays=True))

        for path, client in mandos_clients.iteritems():

            client_proxy_object = self.bus.get_object(self.busname,

                                                      path)

            self.add_client(MandosClientWidget(server_proxy_object

                                               =self.mandos_serv,

                                               proxy_object

                                               =client_proxy_object,

                                               properties=client,

                                               update_hook

                                               =self.refresh,

                                               delete_hook

                                               =self.remove_client,

                                               logger

                                               =self.log_message),

                            path=path)

        self.refresh()

        self._input_callback_tag = (gobject.io_add_watch

                                    (sys.stdin.fileno(),

                                     gobject.IO_IN,

                                     self.process_input))

        self.main_loop.run()

        # Main loop has finished, we should close everything now

        gobject.source_remove(self._input_callback_tag)

        self.screen.stop()

    def stop(self):

        self.main_loop.quit()

    def process_input(self, source, condition):

        keys = self.screen.get_input()

        translations = { "ctrl n": "down",      # Emacs

                         "ctrl p": "up",        # Emacs