#!/usr/bin/python2
#
# The Qubes OS Project, http://www.qubes-os.org
#
# Copyright (C) 2010  Rafal Wojtczuk  <rafal@invisiblethingslab.com>
#
# 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 2
# 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, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
#
#
import os
import dbus
import subprocess
import sys
import fcntl
import shutil
import time

from qubes.qubes import QubesVmCollection
from qubes.qubes import QubesException
from qubes.qubes import QubesDaemonPidfile
from qubes.qubes import QubesDispVmLabels
from qubes.qmemman_client import QMemmanClient

current_savefile = '/var/run/qubes/current-savefile'
current_dvm_conf = '/var/run/qubes/current-dvm.conf'
notify_object = None

class QfileDaemonDvm:
    def __init__(self, name):
        self.name = name
        
    def do_get_dvm(self):
        qmemman_client = QMemmanClient()
        if not qmemman_client.request_memory(400*1024*1024):
            qmemman_client.close()
            errmsg = 'Not enough memory to create DVM. '
            errmsg +='Terminate some appVM and retry.'
            if os.path.exists('/usr/bin/kdialog'):
                subprocess.call(['/usr/bin/kdialog', '--sorry', errmsg])
            else:
                subprocess.call(['/usr/bin/zenity', '--warning', '--text', errmsg])
            return None

        self.tray_notify("Starting new DispVM...")

        qvm_collection = QubesVmCollection()
        qvm_collection.lock_db_for_writing()
        qvm_collection.load()

        vm = qvm_collection.get_vm_by_name(self.name)
        if vm is None:
            sys.stderr.write( 'Domain ' + self.name + ' does not exist ?')
            qvm_collection.unlock_db()
            qmemman_client.close()
            return None
        label = vm.label
        if len(sys.argv) > 4 and len(sys.argv[4]) > 0:
            assert sys.argv[4] in QubesDispVmLabels.keys(), "Invalid label"
            label = QubesDispVmLabels[sys.argv[4]]
        print >>sys.stderr, "time=%s, starting qubes-restore" % (str(time.time()))
        retcode = subprocess.call(['/usr/lib/qubes/qubes-restore',
            current_savefile,
            current_dvm_conf,
            '-u', str(vm.default_user),
            '-c', label.color,
            '-i', label.icon_path,
            '-l', str(label.index)])
        qmemman_client.close()
        if retcode != 0:
            if os.path.exists('/usr/bin/kdialog'):
                subprocess.call(['/usr/bin/kdialog', '--sorry', 'DisposableVM creation failed, see qubes-restore.log'])
            else:
                subprocess.call(['/usr/bin/zenity', '--warning', '--text', 'DisposableVM creation failed, see qubes-restore.log'])
            qvm_collection.unlock_db()
            return None
        f = open('/var/run/qubes/dispVM.xid', 'r');
        disp_xid = f.readline().rstrip('\n')
        disp_name = f.readline().rstrip('\n')
        disptempl = f.readline().rstrip('\n')
        f.close()
        print >>sys.stderr, "time=%s, adding to qubes.xml" % (str(time.time()))
        vm_disptempl = qvm_collection.get_vm_by_name(disptempl);
        if vm_disptempl is None:
            sys.stderr.write( 'Domain ' + disptempl + ' does not exist ?')
            qvm_collection.unlock_db()
            return None
        dispid=int(disp_name[4:])
        dispvm=qvm_collection.add_new_disposablevm(disp_name, vm_disptempl.template, label=label, dispid=dispid, netvm=vm_disptempl.netvm)
        # By default inherit firewall rules from calling VM
        if os.path.exists(vm.firewall_conf):
            disp_firewall_conf = '/var/run/qubes/%s-firewall.xml' % disp_name
            shutil.copy(vm.firewall_conf, disp_firewall_conf)
            dispvm.firewall_conf = disp_firewall_conf
        if len(sys.argv) > 5 and len(sys.argv[5]) > 0:
            assert os.path.exists(sys.argv[5]), "Invalid firewall.conf location"
            dispvm.firewall_conf = sys.argv[5]
        qvm_collection.save()
        qvm_collection.unlock_db()
        # Reload firewall rules
        print >>sys.stderr, "time=%s, reloading firewall" % (str(time.time()))
        for vm in qvm_collection.values():
            if vm.is_proxyvm() and vm.is_running():
                vm.write_iptables_xenstore_entry()

        return disp_name

    def dvm_setup_ok(self):
        dvmdata_dir = '/var/lib/qubes/dvmdata/'
        if not os.path.isfile(current_savefile):
            return False
        if not os.path.isfile(dvmdata_dir+'default-savefile') or not os.path.isfile(dvmdata_dir+'savefile-root'):
            return False
        dvm_mtime = os.stat(current_savefile).st_mtime
        root_mtime = os.stat(dvmdata_dir+'savefile-root').st_mtime
        if dvm_mtime < root_mtime:
            template_name = os.path.basename(os.path.dirname(os.readlink(dvmdata_dir+'savefile-root')))
            if subprocess.call(["xl", "domid", template_name]) == 0:
                self.tray_notify("For optimum performance, you should not start DispVM when its template is running.")
            return False       
        return True

    def tray_notify(self, str, timeout = 3000):
        if notify_object:
            notify_object.Notify("Qubes", 0, "red", "Qubes", str, [], [], timeout, dbus_interface="org.freedesktop.Notifications")

    def tray_notify_error(self, str, timeout = 3000):
        if notify_object:
            notify_object.Notify("Qubes", 0, "dialog-error", "Qubes", str, [], [], timeout, dbus_interface="org.freedesktop.Notifications")

    def get_dvm(self):
        if not self.dvm_setup_ok():
            if os.system("/usr/lib/qubes/qubes-update-dispvm-savefile-with-progress.sh >/dev/null </dev/null" ) != 0:
                self.tray_notify_error("DVM savefile creation failed")
                return None 
        return self.do_get_dvm()

    def remove_disposable_from_qdb(self, name):
        qvm_collection = QubesVmCollection()
        qvm_collection.lock_db_for_writing()
        qvm_collection.load()
        vm = qvm_collection.get_vm_by_name(name)
        if vm is None:
            qvm_collection.unlock_db()
            return False
        qvm_collection.pop(vm.qid)
        qvm_collection.save()
        qvm_collection.unlock_db()

def main():
    global notify_object
    exec_index = sys.argv[1]
    src_vmname = sys.argv[2]
    user = sys.argv[3]
    #accessed directly by get_dvm()
    # sys.argv[4] - override label
    # sys.argv[5] - override firewall

    print >>sys.stderr, "time=%s, qfile-daemon-dvm init" % (str(time.time()))
    try:
        notify_object = dbus.SessionBus().get_object("org.freedesktop.Notifications", "/org/freedesktop/Notifications")
    except dbus.DBusException as e:
        print >>sys.stderr, "Warning: notification service not available: %s" % str(e)
        notify_object = None
    print >>sys.stderr, "time=%s, creating DispVM" % (str(time.time()))
    qfile = QfileDaemonDvm(src_vmname)
    lockf = open("/var/run/qubes/qfile-daemon-dvm.lock", 'a')
    fcntl.fcntl(lockf, fcntl.F_SETFD, fcntl.FD_CLOEXEC)
    fcntl.flock(lockf, fcntl.LOCK_EX)
    dispname = qfile.get_dvm()
    lockf.close()
    if dispname is not None:
        print >>sys.stderr, "time=%s, starting VM process" % (str(time.time()))
        subprocess.call(['/usr/lib/qubes/qrexec-client', '-d', dispname,
            user+':exec /usr/lib/qubes/qubes-rpc-multiplexer ' + exec_index + " " + src_vmname])
        subprocess.call(['/usr/sbin/xl', 'destroy', dispname])
        qfile.remove_disposable_from_qdb(dispname)

main()