mandos-ctl

#!/usr/bin/python
# -*- mode: python; coding: utf-8 -*-
#
# Mandos Monitor - Control and monitor the Mandos server
#
# Copyright © 2008-2018 Teddy Hogeborn
# Copyright © 2008-2018 Björn Påhlsson
#
# This file is part of Mandos.
#
# Mandos 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.
#
#     Mandos 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 Mandos.  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)

try:
    from future_builtins import *
except ImportError:
    pass

import sys
import argparse
import locale
import datetime
import re
import os
import collections
import json

import dbus

if sys.version_info.major == 2:
    str = unicode

locale.setlocale(locale.LC_ALL, "")

tablewords = {
    "Name": "Name",
    "Enabled": "Enabled",
    "Timeout": "Timeout",
    "LastCheckedOK": "Last Successful Check",
    "LastApprovalRequest": "Last Approval Request",
    "Created": "Created",
    "Interval": "Interval",
    "Host": "Host",
    "Fingerprint": "Fingerprint",
    "CheckerRunning": "Check Is Running",
    "LastEnabled": "Last Enabled",
    "ApprovalPending": "Approval Is Pending",
    "ApprovedByDefault": "Approved By Default",
    "ApprovalDelay": "Approval Delay",
    "ApprovalDuration": "Approval Duration",
    "Checker": "Checker",
    "ExtendedTimeout": "Extended Timeout",
    "Expires": "Expires",
    "LastCheckerStatus": "Last Checker Status",
}
defaultkeywords = ("Name", "Enabled", "Timeout", "LastCheckedOK")
domain = "se.recompile"
busname = domain + ".Mandos"
server_path = "/"
server_interface = domain + ".Mandos"
client_interface = domain + ".Mandos.Client"
version = "1.7.20"


try:
    dbus.OBJECT_MANAGER_IFACE
except AttributeError:
    dbus.OBJECT_MANAGER_IFACE = "org.freedesktop.DBus.ObjectManager"


def milliseconds_to_string(ms):
    td = datetime.timedelta(0, 0, 0, ms)
    return ("{days}{hours:02}:{minutes:02}:{seconds:02}"
            .format(days="{}T".format(td.days) if td.days else "",
                    hours=td.seconds // 3600,
                    minutes=(td.seconds % 3600) // 60,
                    seconds=td.seconds % 60))


def rfc3339_duration_to_delta(duration):
    """Parse an RFC 3339 "duration" and return a datetime.timedelta

    >>> rfc3339_duration_to_delta("P7D")
    datetime.timedelta(7)
    >>> rfc3339_duration_to_delta("PT60S")
    datetime.timedelta(0, 60)
    >>> rfc3339_duration_to_delta("PT60M")
    datetime.timedelta(0, 3600)
    >>> rfc3339_duration_to_delta("PT24H")
    datetime.timedelta(1)
    >>> rfc3339_duration_to_delta("P1W")
    datetime.timedelta(7)
    >>> rfc3339_duration_to_delta("PT5M30S")
    datetime.timedelta(0, 330)
    >>> rfc3339_duration_to_delta("P1DT3M20S")
    datetime.timedelta(1, 200)
    """

    # Parsing an RFC 3339 duration with regular expressions is not
    # possible - there would have to be multiple places for the same
    # values, like seconds.  The current code, while more esoteric, is
    # cleaner without depending on a parsing library.  If Python had a
    # built-in library for parsing we would use it, but we'd like to
    # avoid excessive use of external libraries.

    # New type for defining tokens, syntax, and semantics all-in-one
    Token = collections.namedtuple("Token", (
        "regexp",  # To match token; if "value" is not None, must have
                   # a "group" containing digits
        "value",   # datetime.timedelta or None
        "followers"))           # Tokens valid after this token
    # RFC 3339 "duration" tokens, syntax, and semantics; taken from
    # the "duration" ABNF definition in RFC 3339, Appendix A.
    token_end = Token(re.compile(r"$"), None, frozenset())
    token_second = Token(re.compile(r"(\d+)S"),
                         datetime.timedelta(seconds=1),
                         frozenset((token_end, )))
    token_minute = Token(re.compile(r"(\d+)M"),
                         datetime.timedelta(minutes=1),
                         frozenset((token_second, token_end)))
    token_hour = Token(re.compile(r"(\d+)H"),
                       datetime.timedelta(hours=1),
                       frozenset((token_minute, token_end)))
    token_time = Token(re.compile(r"T"),
                       None,
                       frozenset((token_hour, token_minute,
                                  token_second)))
    token_day = Token(re.compile(r"(\d+)D"),
                      datetime.timedelta(days=1),
                      frozenset((token_time, token_end)))
    token_month = Token(re.compile(r"(\d+)M"),
                        datetime.timedelta(weeks=4),
                        frozenset((token_day, token_end)))
    token_year = Token(re.compile(r"(\d+)Y"),
                       datetime.timedelta(weeks=52),
                       frozenset((token_month, token_end)))
    token_week = Token(re.compile(r"(\d+)W"),
                       datetime.timedelta(weeks=1),
                       frozenset((token_end, )))
    token_duration = Token(re.compile(r"P"), None,
                           frozenset((token_year, token_month,
                                      token_day, token_time,
                                      token_week)))
    # Define starting values:
    # Value so far
    value = datetime.timedelta()
    found_token = None
    # Following valid tokens
    followers = frozenset((token_duration, ))
    # String left to parse
    s = duration
    # Loop until end token is found
    while found_token is not token_end:
        # Search for any currently valid tokens
        for token in followers:
            match = token.regexp.match(s)
            if match is not None:
                # Token found
                if token.value is not None:
                    # Value found, parse digits
                    factor = int(match.group(1), 10)
                    # Add to value so far
                    value += factor * token.value
                # Strip token from string
                s = token.regexp.sub("", s, 1)
                # Go to found token
                found_token = token
                # Set valid next tokens
                followers = found_token.followers
                break
        else:
            # No currently valid tokens were found
            raise ValueError("Invalid RFC 3339 duration: {!r}"
                             .format(duration))
    # End token found
    return value


def string_to_delta(interval):
    """Parse a string and return a datetime.timedelta

    >>> string_to_delta('7d')
    datetime.timedelta(7)
    >>> string_to_delta('60s')
    datetime.timedelta(0, 60)
    >>> string_to_delta('60m')
    datetime.timedelta(0, 3600)
    >>> string_to_delta('24h')
    datetime.timedelta(1)
    >>> string_to_delta('1w')
    datetime.timedelta(7)
    >>> string_to_delta('5m 30s')
    datetime.timedelta(0, 330)
    """

    try:
        return rfc3339_duration_to_delta(interval)
    except ValueError:
        pass

    value = datetime.timedelta(0)
    regexp = re.compile(r"(\d+)([dsmhw]?)")

    for num, suffix in regexp.findall(interval):
        if suffix == "d":
            value += datetime.timedelta(int(num))
        elif suffix == "s":
            value += datetime.timedelta(0, int(num))
        elif suffix == "m":
            value += datetime.timedelta(0, 0, 0, 0, int(num))
        elif suffix == "h":
            value += datetime.timedelta(0, 0, 0, 0, 0, int(num))
        elif suffix == "w":
            value += datetime.timedelta(0, 0, 0, 0, 0, 0, int(num))
        elif suffix == "":
            value += datetime.timedelta(0, 0, 0, int(num))
    return value


def print_clients(clients, keywords):
    def valuetostring(value, keyword):
        if type(value) is dbus.Boolean:
            return "Yes" if value else "No"
        if keyword in ("Timeout", "Interval", "ApprovalDelay",
                       "ApprovalDuration", "ExtendedTimeout"):
            return milliseconds_to_string(value)
        return str(value)

    # Create format string to print table rows
    format_string = " ".join("{{{key}:{width}}}".format(
        width=max(len(tablewords[key]),
                  max(len(valuetostring(client[key], key))
                      for client in clients)),
        key=key)
                             for key in keywords)
    # Print header line
    print(format_string.format(**tablewords))
    for client in clients:
        print(format_string
              .format(**{key: valuetostring(client[key], key)
                         for key in keywords}))


def has_actions(options):
    return any((options.enable,
                options.disable,
                options.bump_timeout,
                options.start_checker,
                options.stop_checker,
                options.is_enabled,
                options.remove,
                options.checker is not None,
                options.timeout is not None,
                options.extended_timeout is not None,
                options.interval is not None,
                options.approved_by_default is not None,
                options.approval_delay is not None,
                options.approval_duration is not None,
                options.host is not None,
                options.secret is not None,
                options.approve,
                options.deny))


def main():
    parser = argparse.ArgumentParser()
    parser.add_argument("--version", action="version",
                        version="%(prog)s {}".format(version),
                        help="show version number and exit")
    parser.add_argument("-a", "--all", action="store_true",
                        help="Select all clients")
    parser.add_argument("-v", "--verbose", action="store_true",
                        help="Print all fields")
    parser.add_argument("-j", "--dump-json", action="store_true",
                        help="Dump client data in JSON format")
    parser.add_argument("-e", "--enable", action="store_true",
                        help="Enable client")
    parser.add_argument("-d", "--disable", action="store_true",
                        help="disable client")
    parser.add_argument("-b", "--bump-timeout", action="store_true",
                        help="Bump timeout for client")
    parser.add_argument("--start-checker", action="store_true",
                        help="Start checker for client")
    parser.add_argument("--stop-checker", action="store_true",
                        help="Stop checker for client")
    parser.add_argument("-V", "--is-enabled", action="store_true",
                        help="Check if client is enabled")
    parser.add_argument("-r", "--remove", action="store_true",
                        help="Remove client")
    parser.add_argument("-c", "--checker",
                        help="Set checker command for client")
    parser.add_argument("-t", "--timeout",
                        help="Set timeout for client")
    parser.add_argument("--extended-timeout",
                        help="Set extended timeout for client")
    parser.add_argument("-i", "--interval",
                        help="Set checker interval for client")
    parser.add_argument("--approve-by-default", action="store_true",
                        default=None, dest="approved_by_default",
                        help="Set client to be approved by default")
    parser.add_argument("--deny-by-default", action="store_false",
                        dest="approved_by_default",
                        help="Set client to be denied by default")
    parser.add_argument("--approval-delay",
                        help="Set delay before client approve/deny")
    parser.add_argument("--approval-duration",
                        help="Set duration of one client approval")
    parser.add_argument("-H", "--host", help="Set host for client")
    parser.add_argument("-s", "--secret",
                        type=argparse.FileType(mode="rb"),
                        help="Set password blob (file) for client")
    parser.add_argument("-A", "--approve", action="store_true",
                        help="Approve any current client request")
    parser.add_argument("-D", "--deny", action="store_true",
                        help="Deny any current client request")
    parser.add_argument("--check", action="store_true",
                        help="Run self-test")
    parser.add_argument("client", nargs="*", help="Client name")
    options = parser.parse_args()

    if has_actions(options) and not (options.client or options.all):
        parser.error("Options require clients names or --all.")
    if options.verbose and has_actions(options):
        parser.error("--verbose can only be used alone.")
    if options.dump_json and (options.verbose
                              or has_actions(options)):
        parser.error("--dump-json can only be used alone.")
    if options.all and not has_actions(options):
        parser.error("--all requires an action.")

    if options.check:
        import doctest
        fail_count, test_count = doctest.testmod()
        sys.exit(os.EX_OK if fail_count == 0 else 1)

    try:
        bus = dbus.SystemBus()
        mandos_dbus_objc = bus.get_object(busname, server_path)
    except dbus.exceptions.DBusException:
        print("Could not connect to Mandos server", file=sys.stderr)
        sys.exit(1)

    mandos_serv = dbus.Interface(mandos_dbus_objc,
                                 dbus_interface=server_interface)
    mandos_serv_object_manager = dbus.Interface(
        mandos_dbus_objc, dbus_interface=dbus.OBJECT_MANAGER_IFACE)

    # block stderr since dbus library prints to stderr
    null = os.open(os.path.devnull, os.O_RDWR)
    stderrcopy = os.dup(sys.stderr.fileno())
    os.dup2(null, sys.stderr.fileno())
    os.close(null)
    try:
        try:
            mandos_clients = {path: ifs_and_props[client_interface]
                              for path, ifs_and_props in
                              mandos_serv_object_manager
                              .GetManagedObjects().items()
                              if client_interface in ifs_and_props}
        finally:
            # restore stderr
            os.dup2(stderrcopy, sys.stderr.fileno())
            os.close(stderrcopy)
    except dbus.exceptions.DBusException as e:
        print("Access denied: "
              "Accessing mandos server through D-Bus: {}".format(e),
              file=sys.stderr)
        sys.exit(1)

    # Compile dict of (clients: properties) to process
    clients = {}

    if options.all or not options.client:
        clients = {bus.get_object(busname, path): properties
                   for path, properties in mandos_clients.items()}
    else:
        for name in options.client:
            for path, client in mandos_clients.items():
                if client["Name"] == name:
                    client_objc = bus.get_object(busname, path)
                    clients[client_objc] = client
                    break
            else:
                print("Client not found on server: {!r}"
                      .format(name), file=sys.stderr)
                sys.exit(1)

    if not has_actions(options) and clients:
        if options.verbose or options.dump_json:
            keywords = ("Name", "Enabled", "Timeout", "LastCheckedOK",
                        "Created", "Interval", "Host", "Fingerprint",
                        "CheckerRunning", "LastEnabled",
                        "ApprovalPending", "ApprovedByDefault",
                        "LastApprovalRequest", "ApprovalDelay",
                        "ApprovalDuration", "Checker",
                        "ExtendedTimeout", "Expires",
                        "LastCheckerStatus")
        else:
            keywords = defaultkeywords

        if options.dump_json:
            json.dump({client["Name"]: {key:
                                        bool(client[key])
                                        if isinstance(client[key],
                                                      dbus.Boolean)
                                        else client[key]
                                        for key in keywords}
                       for client in clients.values()},
                      fp=sys.stdout, indent=4,
                      separators=(',', ': '))
            print()
        else:
            print_clients(clients.values(), keywords)
    else:
        # Process each client in the list by all selected options
        for client in clients:

            def set_client_prop(prop, value):
                """Set a Client D-Bus property"""
                client.Set(client_interface, prop, value,
                           dbus_interface=dbus.PROPERTIES_IFACE)

            def set_client_prop_ms(prop, value):
                """Set a Client D-Bus property, converted
                from a string to milliseconds."""
                set_client_prop(prop,
                                string_to_delta(value).total_seconds()
                                * 1000)

            if options.remove:
                mandos_serv.RemoveClient(client.__dbus_object_path__)
            if options.enable:
                set_client_prop("Enabled", dbus.Boolean(True))
            if options.disable:
                set_client_prop("Enabled", dbus.Boolean(False))
            if options.bump_timeout:
                set_client_prop("LastCheckedOK", "")
            if options.start_checker:
                set_client_prop("CheckerRunning", dbus.Boolean(True))
            if options.stop_checker:
                set_client_prop("CheckerRunning", dbus.Boolean(False))
            if options.is_enabled:
                if client.Get(client_interface, "Enabled",
                              dbus_interface=dbus.PROPERTIES_IFACE):
                    sys.exit(0)
                else:
                    sys.exit(1)
            if options.checker is not None:
                set_client_prop("Checker", options.checker)
            if options.host is not None:
                set_client_prop("Host", options.host)
            if options.interval is not None:
                set_client_prop_ms("Interval", options.interval)
            if options.approval_delay is not None:
                set_client_prop_ms("ApprovalDelay",
                                   options.approval_delay)
            if options.approval_duration is not None:
                set_client_prop_ms("ApprovalDuration",
                                   options.approval_duration)
            if options.timeout is not None:
                set_client_prop_ms("Timeout", options.timeout)
            if options.extended_timeout is not None:
                set_client_prop_ms("ExtendedTimeout",
                                   options.extended_timeout)
            if options.secret is not None:
                set_client_prop("Secret",
                                dbus.ByteArray(options.secret.read()))
            if options.approved_by_default is not None:
                set_client_prop("ApprovedByDefault",
                                dbus.Boolean(options
                                             .approved_by_default))
            if options.approve:
                client.Approve(dbus.Boolean(True),
                               dbus_interface=client_interface)
            elif options.deny:
                client.Approve(dbus.Boolean(False),
                               dbus_interface=client_interface)


if __name__ == "__main__":
    main()