[snf-image-creator] / image_creator / os_type / windows.py

# -*- coding: utf-8 -*-
#
# Copyright 2012 GRNET S.A. All rights reserved.
#
# Redistribution and use in source and binary forms, with or
# without modification, are permitted provided that the following
# conditions are met:
#
#   1. Redistributions of source code must retain the above
#      copyright notice, this list of conditions and the following
#      disclaimer.
#
#   2. Redistributions in binary form must reproduce the above
#      copyright notice, this list of conditions and the following
#      disclaimer in the documentation and/or other materials
#      provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS
# OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR
# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
# USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
#
# The views and conclusions contained in the software and
# documentation are those of the authors and should not be
# interpreted as representing official policies, either expressed
# or implied, of GRNET S.A.

"""This module hosts OS-specific code common for the various Microsoft
Windows OSs."""

from image_creator.os_type import OSBase, sysprep, add_sysprep_param
from image_creator.util import FatalError, check_guestfs_version, \
    get_kvm_binary
from image_creator.winexe import WinEXE, WinexeTimeout

import hivex
import tempfile
import os
import signal
import time
import random
import string
import subprocess
import struct

# For more info see: http://technet.microsoft.com/en-us/library/jj612867.aspx
KMS_CLIENT_SETUP_KEYS = {
    "Windows 8 Professional": "NG4HW-VH26C-733KW-K6F98-J8CK4",
    "Windows 8 Professional N": "XCVCF-2NXM9-723PB-MHCB7-2RYQQ",
    "Windows 8 Enterprise": "32JNW-9KQ84-P47T8-D8GGY-CWCK7",
    "Windows 8 Enterprise N": "JMNMF-RHW7P-DMY6X-RF3DR-X2BQT",
    "Windows Server 2012 Core": "BN3D2-R7TKB-3YPBD-8DRP2-27GG4",
    "Windows Server 2012 Core N": "8N2M2-HWPGY-7PGT9-HGDD8-GVGGY",
    "Windows Server 2012 Core Single Language":
    "2WN2H-YGCQR-KFX6K-CD6TF-84YXQ",
    "Windows Server 2012 Core Country Specific":
    "4K36P-JN4VD-GDC6V-KDT89-DYFKP",
    "Windows Server 2012 Server Standard": "XC9B7-NBPP2-83J2H-RHMBY-92BT4",
    "Windows Server 2012 Standard Core": "XC9B7-NBPP2-83J2H-RHMBY-92BT4",
    "Windows Server 2012 MultiPoint Standard": "HM7DN-YVMH3-46JC3-XYTG7-CYQJJ",
    "Windows Server 2012 MultiPoint Premium": "XNH6W-2V9GX-RGJ4K-Y8X6F-QGJ2G",
    "Windows Server 2012 Datacenter": "48HP8-DN98B-MYWDG-T2DCC-8W83P",
    "Windows Server 2012 Datacenter Core": "48HP8-DN98B-MYWDG-T2DCC-8W83P",
    "Windows 7 Professional": "FJ82H-XT6CR-J8D7P-XQJJ2-GPDD4",
    "Windows 7 Professional N": "MRPKT-YTG23-K7D7T-X2JMM-QY7MG",
    "Windows 7 Professional E": "W82YF-2Q76Y-63HXB-FGJG9-GF7QX",
    "Windows 7 Enterprise": "33PXH-7Y6KF-2VJC9-XBBR8-HVTHH",
    "Windows 7 Enterprise N": "YDRBP-3D83W-TY26F-D46B2-XCKRJ",
    "Windows 7 Enterprise E": "C29WB-22CC8-VJ326-GHFJW-H9DH4",
    "Windows Server 2008 R2 Web": "6TPJF-RBVHG-WBW2R-86QPH-6RTM4",
    "Windows Server 2008 R2 HPC edition": "TT8MH-CG224-D3D7Q-498W2-9QCTX",
    "Windows Server 2008 R2 Standard": "YC6KT-GKW9T-YTKYR-T4X34-R7VHC",
    "Windows Server 2008 R2 Enterprise": "489J6-VHDMP-X63PK-3K798-CPX3Y",
    "Windows Server 2008 R2 Datacenter": "74YFP-3QFB3-KQT8W-PMXWJ-7M648",
    "Windows Server 2008 R2 for Itanium-based Systems":
    "GT63C-RJFQ3-4GMB6-BRFB9-CB83V",
    "Windows Vista Business": "YFKBB-PQJJV-G996G-VWGXY-2V3X8",
    "Windows Vista Business N": "HMBQG-8H2RH-C77VX-27R82-VMQBT",
    "Windows Vista Enterprise": "VKK3X-68KWM-X2YGT-QR4M6-4BWMV",
    "Windows Vista Enterprise N": "VTC42-BM838-43QHV-84HX6-XJXKV",
    "Windows Web Server 2008": "WYR28-R7TFJ-3X2YQ-YCY4H-M249D",
    "Windows Server 2008 Standard": "TM24T-X9RMF-VWXK6-X8JC9-BFGM2",
    "Windows Server 2008 Standard without Hyper-V":
    "W7VD6-7JFBR-RX26B-YKQ3Y-6FFFJ",
    "Windows Server 2008 Enterprise":
    "YQGMW-MPWTJ-34KDK-48M3W-X4Q6V",
    "Windows Server 2008 Enterprise without Hyper-V":
    "39BXF-X8Q23-P2WWT-38T2F-G3FPG",
    "Windows Server 2008 HPC": "RCTX3-KWVHP-BR6TB-RB6DM-6X7HP",
    "Windows Server 2008 Datacenter": "7M67G-PC374-GR742-YH8V4-TCBY3",
    "Windows Server 2008 Datacenter without Hyper-V":
    "22XQ2-VRXRG-P8D42-K34TD-G3QQC",
    "Windows Server 2008 for Itanium-Based Systems":
    "4DWFP-JF3DJ-B7DTH-78FJB-PDRHK"}

_POSINT = lambda x: type(x) == int and x >= 0


class Windows(OSBase):
    """OS class for Windows"""
    @add_sysprep_param(
        'shutdown_timeout', int, 120, "Shutdown Timeout (seconds)", _POSINT)
    @add_sysprep_param(
        'boot_timeout', int, 300, "Boot Timeout (seconds)", _POSINT)
    @add_sysprep_param(
        'connection_retries', int, 5, "Connection Retries", _POSINT)
    @add_sysprep_param('password', str, None, 'Image Administrator Password')
    def __init__(self, image, **kargs):
        super(Windows, self).__init__(image, **kargs)

        device = self.image.g.part_to_dev(self.root)

        self.last_part_num = self.image.g.part_list(device)[-1]['part_num']
        self.last_drive = None
        self.system_drive = None

        for drive, partition in self.image.g.inspect_get_drive_mappings(self.root):
            if partition == "%s%d" % (device, self.last_part_num):
                self.last_drive = drive
            if partition == self.root:
                self.system_drive = drive

        assert self.system_drive

        self.product_name = self.image.g.inspect_get_product_name(self.root)
        self.syspreped = False

    @sysprep('Disabling IPv6 privacy extensions')
    def disable_ipv6_privacy_extensions(self):
        """Disable IPv6 privacy extensions"""

        self._guest_exec('netsh interface ipv6 set global '
                         'randomizeidentifiers=disabled store=persistent')

    @sysprep('Disabling Teredo interface')
    def disable_teredo(self):
        """Disable Teredo interface"""

        self._guest_exec('netsh interface teredo set state disabled')

    @sysprep('Disabling ISATAP Adapters')
    def disable_isatap(self):
        """Disable ISATAP Adapters"""

        self._guest_exec('netsh interface isa set state disabled')

    @sysprep('Enabling ping responses')
    def enable_pings(self):
        """Enable ping responses"""

        self._guest_exec('netsh firewall set icmpsetting 8')

    @sysprep('Disabling hibernation support')
    def disable_hibernation(self):
        """Disable hibernation support and remove the hibernation file"""

        self._guest_exec(r'powercfg.exe /hibernate off')

    @sysprep('Setting the system clock to UTC')
    def utc(self):
        """Set the hardware clock to UTC"""

        path = r'HKLM\SYSTEM\CurrentControlSet\Control\TimeZoneInformation'
        self._guest_exec(
            r'REG ADD %s /v RealTimeIsUniversal /t REG_DWORD /d 1 /f' % path)

    @sysprep('Clearing the event logs')
    def clear_logs(self):
        """Clear all the event logs"""

        self._guest_exec(
            r"cmd /q /c for /f %l in ('wevtutil el') do wevtutil cl %l")

    @sysprep('Executing Sysprep on the image (may take more that 10 minutes)')
    def microsoft_sysprep(self):
        """Run the Microsoft System Preparation Tool. This will remove
        system-specific data and will make the image ready to be deployed.
        After this no other task may run.
        """

        self._guest_exec(r'C:\Windows\system32\sysprep\sysprep '
                         r'/quiet /generalize /oobe /shutdown')
        self.syspreped = True

    @sysprep('Converting the image into a KMS client', enabled=False)
    def kms_client_setup(self):
        """Install the appropriate KMS client setup key to the image to convert
        it to a KMS client. Computers that are running volume licensing
        editions of Windows 8, Windows Server 2012, Windows 7, Windows Server
        2008 R2, Windows Vista, and Windows Server 2008 are, by default, KMS
        clients with no additional configuration needed.
        """
        try:
            setup_key = KMS_CLIENT_SETUP_KEYS[self.product_name]
        except KeyError:
            self.out.warn(
                "Don't know the KMS client setup key for product: `%s'" %
                self.product_name)
            return

        self._guest_exec(
            r"cscript \Windows\system32\slmgr.vbs /ipk %s" % setup_key)

    @sysprep('Shrinking the last filesystem')
    def shrink(self):
        """Shrink the last filesystem. Make sure the filesystem is defragged"""

        # Query for the maximum number of reclaimable bytes
        cmd = (
            r'cmd /Q /V:ON /C "SET SCRIPT=%TEMP%\QUERYMAX_%RANDOM%.TXT & ' +
            r'ECHO SELECT DISK 0 > %SCRIPT% & ' +
            'ECHO SELECT PARTITION %d >> %%SCRIPT%% & ' % self.last_part_num +
            r'ECHO SHRINK QUERYMAX >> %SCRIPT% & ' +
            r'ECHO EXIT >> %SCRIPT% & ' +
            r'DISKPART /S %SCRIPT% & ' +
            r'IF NOT !ERRORLEVEL! EQU 0 EXIT /B 1 & ' +
            r'DEL /Q %SCRIPT%"')

        stdout, stderr, rc = self._guest_exec(cmd)

        querymax = None
        for line in stdout.splitlines():
            # diskpart will return something like this:
            #
            #   The maximum number of reclaimable bytes is: xxxx MB
            #
            if line.find('reclaimable') >= 0:
                querymax = line.split(':')[1].split()[0].strip()
                assert querymax.isdigit(), \
                    "Number of reclaimable bytes not a number"

        if querymax is None:
            FatalError("Error in shrinking! "
                       "Couldn't find the max number of reclaimable bytes!")

        querymax = int(querymax)
        # From ntfsresize:
        # Practically the smallest shrunken size generally is at around
        # "used space" + (20-200 MB). Please also take into account that
        # Windows might need about 50-100 MB free space left to boot safely.
        # I'll give 100MB extra space just to be sure
        querymax -= 100

        if querymax < 0:
            self.out.warn("Not enought available space to shrink the image!")
            return

        self.out.output("\tReclaiming %dMB ..." % querymax)

        cmd = (
            r'cmd /Q /V:ON /C "SET SCRIPT=%TEMP%\QUERYMAX_%RANDOM%.TXT & ' +
            r'ECHO SELECT DISK 0 > %SCRIPT% & ' +
            'ECHO SELECT PARTITION %d >> %%SCRIPT%% & ' % self.last_part_num +
            'ECHO SHRINK DESIRED=%d >> %%SCRIPT%% & ' % querymax +
            r'ECHO EXIT >> %SCRIPT% & ' +
            r'DISKPART /S %SCRIPT% & ' +
            r'IF NOT !ERRORLEVEL! EQU 0 EXIT /B 1 & ' +
            r'DEL /Q %SCRIPT%"')

        stdout, stderr, rc = self._guest_exec(cmd)

        for line in stdout.splitlines():
            if line.find('shrunk') >= 0:
                self.out.output(line)

    def do_sysprep(self):
        """Prepare system for image creation."""

        if getattr(self, 'syspreped', False):
            raise FatalError("Image is already syspreped!")

        txt = "System preparation parameter: `%s' is needed but missing!"
        for name, param in self.needed_sysprep_params.items():
            if name not in self.sysprep_params:
                raise FatalError(txt % name)

        self.mount(readonly=False)
        try:
            disabled_uac = self._update_uac_remote_setting(1)
            token = self._enable_os_monitor()

            # disable the firewalls
            firewall_states = self._update_firewalls(0, 0, 0)

            # Delete the pagefile. It will be recreated when the system boots
            systemroot = self.image.g.inspect_get_windows_systemroot(self.root)
            try:
                pagefile = "%s/pagefile.sys" % systemroot
                self.image.g.rm_rf(self.image.g.case_sensitive_path(pagefile))
            except RuntimeError:
                pass

        finally:
            self.umount()

        self.out.output("Shutting down helper VM ...", False)
        self.image.g.sync()
        # guestfs_shutdown which is the prefered way to shutdown the backend
        # process was introduced in version 1.19.16
        if check_guestfs_version(self.g, 1, 19, 16) >= 0:
            self.image.g.shutdown()
        else:
            self.image.g.kill_subprocess()

        self.out.success('done')

        vm = None
        monitor = None
        try:
            self.out.output("Starting windows VM ...", False)
            monitorfd, monitor = tempfile.mkstemp()
            os.close(monitorfd)
            vm = _VM(self.image.device, monitor, self.sysprep_params)
            self.out.success("started (console on vnc display: %d)." %
                             vm.display)

            self.out.output("Waiting for OS to boot ...", False)
            self._wait_vm_boot(vm, monitor, token)
            self.out.success('done')

            self.out.output("Checking connectivity to the VM ...", False)
            self._check_connectivity()
            self.out.success('done')

            self.out.output("Disabling automatic logon ...", False)
            self._disable_autologon()
            self.out.success('done')

            self.out.output('Preparing system for image creation:')

            tasks = self.list_syspreps()
            enabled = [task for task in tasks if task.enabled]
            size = len(enabled)

            # Make sure shrink runs in the end, before ms sysprep
            enabled = [task for task in enabled if
                       self.sysprep_info(task).name != 'shrink']

            if len(enabled) != size:
                enabled.append(self.shrink)

            # Make sure the ms sysprep is the last task to run if it is enabled
            enabled = [task for task in enabled if
                       self.sysprep_info(task).name != 'microsoft-sysprep']

            ms_sysprep_enabled = False
            if len(enabled) != size:
                enabled.append(self.microsoft_sysprep)
                ms_sysprep_enabled = True

            cnt = 0
            for task in enabled:
                cnt += 1
                self.out.output(('(%d/%d)' % (cnt, size)).ljust(7), False)
                task()
                setattr(task.im_func, 'executed', True)

            self.out.output("Sending shut down command ...", False)
            if not ms_sysprep_enabled:
                self._shutdown()
            self.out.success("done")

            self.out.output("Waiting for windows to shut down ...", False)
            vm.wait(self.sysprep_params['shutdown_timeout'])
            self.out.success("done")
        finally:
            if monitor is not None:
                os.unlink(monitor)

            try:
                if vm is not None:
                    self.out.output("Destroying windows VM ...", False)
                    vm.destroy()
                    self.out.success("done")
            finally:
                self.out.output("Relaunching helper VM (may take a while) ...",
                                False)
                self.image.g.launch()
                self.out.success('done')

                self.mount(readonly=False)
                try:
                    if disabled_uac:
                        self._update_uac_remote_setting(0)

                    self._update_firewalls(*firewall_states)
                finally:
                    self.umount()

    def _shutdown(self):
        """Shuts down the windows VM"""
        self._guest_exec(r'shutdown /s /t 5')

    def _wait_vm_boot(self, vm, fname, msg):
        """Wait until a message appears on a file or the vm process dies"""

        for _ in range(self.sysprep_params['boot_timeout']):
            time.sleep(1)
            with open(fname) as f:
                for line in f:
                    if line.startswith(msg):
                        return True
            if not vm.isalive():
                raise FatalError("Windows VM died unexpectedly!")

        raise FatalError("Windows VM booting timed out!")

    def _disable_autologon(self):
        """Disable automatic logon on the windows image"""

        winlogon = \
            r'"HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon"'

        self._guest_exec('REG DELETE %s /v DefaultUserName /f' % winlogon)
        self._guest_exec('REG DELETE %s /v DefaultPassword /f' % winlogon)
        self._guest_exec('REG DELETE %s /v AutoAdminLogon /f' % winlogon)

    def _registry_file_path(self, regfile):
        """Retrieves the case sensitive path to a registry file"""

        systemroot = self.image.g.inspect_get_windows_systemroot(self.root)
        path = "%s/system32/config/%s" % (systemroot, regfile)
        try:
            path = self.image.g.case_sensitive_path(path)
        except RuntimeError as error:
            raise FatalError("Unable to retrieve registry file: %s. Reason: %s"
                             % (regfile, str(error)))
        return path

    def _enable_os_monitor(self):
        """Add a script in the registry that will send a random string to the
        first serial port when the windows image finishes booting.
        """

        token = "".join(random.choice(string.ascii_letters) for x in range(16))

        path = self._registry_file_path('SOFTWARE')
        softwarefd, software = tempfile.mkstemp()
        try:
            os.close(softwarefd)
            self.image.g.download(path, software)

            h = hivex.Hivex(software, write=True)

            # Enable automatic logon.
            # This is needed because we need to execute a script that we add in
            # the RunOnce registry entry and those programs only get executed
            # when a user logs on. There is a RunServicesOnce registry entry
            # whose keys get executed in the background when the logon dialog
            # box first appears, but they seem to only work with services and
            # not arbitrary command line expressions :-(
            #
            # Instructions on how to turn on automatic logon in Windows can be
            # found here: http://support.microsoft.com/kb/324737
            #
            # Warning: Registry change will not work if the “Logon Banner” is
            # defined on the server either by a Group Policy object (GPO) or by
            # a local policy.

            winlogon = h.root()
            for child in ('Microsoft', 'Windows NT', 'CurrentVersion',
                          'Winlogon'):
                winlogon = h.node_get_child(winlogon, child)

            h.node_set_value(
                winlogon,
                {'key': 'DefaultUserName', 't': 1,
                 'value': "Administrator".encode('utf-16le')})
            h.node_set_value(
                winlogon,
                {'key': 'DefaultPassword', 't': 1,
                 'value':  self.sysprep_params['password'].encode('utf-16le')})
            h.node_set_value(
                winlogon,
                {'key': 'AutoAdminLogon', 't': 1,
                 'value': "1".encode('utf-16le')})

            key = h.root()
            for child in ('Microsoft', 'Windows', 'CurrentVersion'):
                key = h.node_get_child(key, child)

            runonce = h.node_get_child(key, "RunOnce")
            if runonce is None:
                runonce = h.node_add_child(key, "RunOnce")

            value = (
                r'C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe '
                r'-ExecutionPolicy RemoteSigned '
                r'"&{$port=new-Object System.IO.Ports.SerialPort COM1,9600,'
                r'None,8,one;$port.open();$port.WriteLine(\"' + token + r'\");'
                r'$port.Close()}"').encode('utf-16le')

            h.node_set_value(runonce,
                             {'key': "BootMonitor", 't': 1, 'value': value})

            value = (
                r'REG ADD HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion'
                r'\policies\system /v LocalAccountTokenFilterPolicy'
                r' /t REG_DWORD /d 1 /f').encode('utf-16le')

            h.node_set_value(runonce,
                             {'key': "UpdateRegistry", 't': 1, 'value': value})

            h.commit(None)

            self.image.g.upload(software, path)
        finally:
            os.unlink(software)

        return token

    def _update_firewalls(self, domain, public, standard):
        """Enables or disables the firewall for the Domain, the Public and the
        Standard profile. Returns a triplete with the old values.

        1 will enable a firewall and 0 will disable it
        """

        if domain not in (0, 1):
            raise ValueError("Valid values for domain parameter are 0 and 1")

        if public not in (0, 1):
            raise ValueError("Valid values for public parameter are 0 and 1")

        if standard not in (0, 1):
            raise ValueError("Valid values for standard parameter are 0 and 1")

        path = self._registry_file_path("SYSTEM")
        systemfd, system = tempfile.mkstemp()
        try:
            os.close(systemfd)
            self.image.g.download(path, system)

            h = hivex.Hivex(system, write=True)

            select = h.node_get_child(h.root(), 'Select')
            current_value = h.node_get_value(select, 'Current')

            # expecting a little endian dword
            assert h.value_type(current_value)[1] == 4
            current = "%03d" % h.value_dword(current_value)

            firewall_policy = h.root()
            for child in ('ControlSet%s' % current, 'services', 'SharedAccess',
                          'Parameters', 'FirewallPolicy'):
                firewall_policy = h.node_get_child(firewall_policy, child)

            old_values = []
            new_values = [domain, public, standard]
            for profile in ('Domain', 'Public', 'Standard'):
                node = h.node_get_child(firewall_policy, '%sProfile' % profile)

                old_value = h.node_get_value(node, 'EnableFirewall')

                # expecting a little endian dword
                assert h.value_type(old_value)[1] == 4
                old_values.append(h.value_dword(old_value))

                h.node_set_value(
                    node, {'key': 'EnableFirewall', 't': 4L,
                           'value': struct.pack("<I", new_values.pop(0))})

            h.commit(None)
            self.image.g.upload(system, path)

        finally:
            os.unlink(system)

        return old_values

    def _update_uac_remote_setting(self, value):
        """Updates the registry key value:
        [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies
        \System]"LocalAccountTokenFilterPolicy"

        value = 1 will disable the UAC remote restrictions
        value = 0 will enable the UAC remote restrictions

        For more info see here: http://support.microsoft.com/kb/951016

        Returns:
            True if the key is changed
            False if the key is unchanged
        """

        if value not in (0, 1):
            raise ValueError("Valid values for value parameter are 0 and 1")

        path = self._registry_file_path('SOFTWARE')
        softwarefd, software = tempfile.mkstemp()
        try:
            os.close(softwarefd)
            self.image.g.download(path, software)

            h = hivex.Hivex(software, write=True)

            key = h.root()
            for child in ('Microsoft', 'Windows', 'CurrentVersion', 'Policies',
                          'System'):
                key = h.node_get_child(key, child)

            policy = None
            for val in h.node_values(key):
                if h.value_key(val) == "LocalAccountTokenFilterPolicy":
                    policy = val

            if policy is not None:
                dword = h.value_dword(policy)
                if dword == value:
                    return False
            elif value == 0:
                return False

            new_value = {'key': "LocalAccountTokenFilterPolicy", 't': 4L,
                         'value': struct.pack("<I", value)}

            h.node_set_value(key, new_value)
            h.commit(None)

            self.image.g.upload(software, path)

        finally:
            os.unlink(software)

        return True

    def _do_collect_metadata(self):
        """Collect metadata about the OS"""
        super(Windows, self)._do_collect_metadata()
        self.meta["USERS"] = " ".join(self._get_users())

    def _get_users(self):
        """Returns a list of users found in the images"""
        samfd, sam = tempfile.mkstemp()
        try:
            os.close(samfd)
            self.image.g.download(self._registry_file_path('SAM'), sam)

            h = hivex.Hivex(sam)

            # Navigate to /SAM/Domains/Account/Users
            users_node = h.root()
            for child in ('SAM', 'Domains', 'Account', 'Users'):
                users_node = h.node_get_child(users_node, child)

            # Navigate to /SAM/Domains/Account/Users/Names
            names_node = h.node_get_child(users_node, 'Names')

            # HKEY_LOCAL_MACHINE\SAM\SAM\Domains\Account\Users\%RID%
            # HKEY_LOCAL_MACHINE\SAM\SAM\Domains\Account\Users\Names\%Username%
            #
            # The RID (relative identifier) of each user is stored as the type!
            # (not the value) of the default key of the node under Names whose
            # name is the user's username. Under the RID node, there in a F
            # value that contains information about this user account.
            #
            # See sam.h of the chntpw project on how to translate the F value
            # of an account in the registry. Bytes 56 & 57 are the account type
            # and status flags. The first bit is the 'account disabled' bit
            disabled = lambda f: int(f[56].encode('hex'), 16) & 0x01

            users = []
            for user_node in h.node_children(names_node):
                username = h.node_name(user_node)
                rid = h.value_type(h.node_get_value(user_node, ""))[0]
                # if RID is 500 (=0x1f4), the corresponding node name under
                # Users is '000001F4'
                key = ("%8.x" % rid).replace(' ', '0').upper()
                rid_node = h.node_get_child(users_node, key)
                f_value = h.value_value(h.node_get_value(rid_node, 'F'))[1]

                if disabled(f_value):
                    self.out.warn("Found disabled `%s' account!" % username)
                    continue

                users.append(username)

        finally:
            os.unlink(sam)

        # Filter out the guest account
        return users

    def _check_connectivity(self):
        """Check if winexe works on the Windows VM"""

        retries = self.sysprep_params['connection_retries']
        # If the connection_retries parameter is set to 0 disable the
        # connectivity check
        if retries == 0:
            return True

        passwd = self.sysprep_params['password']
        winexe = WinEXE('Administrator', passwd, 'localhost')
        winexe.uninstall().debug(9)

        for i in range(retries):
            (stdout, stderr, rc) = winexe.run('cmd /C')
            if rc == 0:
                return True
            log = tempfile.NamedTemporaryFile(delete=False)
            try:
                log.file.write(stdout)
            finally:
                log.close()
            self.out.output("failed! See: `%s' for the full output" % log.name)
            if i < retries - 1:
                self.out.output("retrying ...", False)

        raise FatalError("Connection to the Windows VM failed after %d retries"
                         % retries)

    def _guest_exec(self, command, fatal=True):
        """Execute a command on a windows VM"""

        passwd = self.sysprep_params['password']

        winexe = WinEXE('Administrator', passwd, 'localhost')
        winexe.runas('Administrator', passwd).uninstall()

        try:
            (stdout, stderr, rc) = winexe.run(command)
        except WinexeTimeout:
            FatalError("Command: `%s' timeout out." % command)

        if rc != 0 and fatal:
            reason = stderr if len(stderr) else stdout
            self.out.output("Command: `%s' failed (rc=%d). Reason: %s" %
                            (command, rc, reason))
            raise FatalError("Command: `%s' failed (rc=%d). Reason: %s" %
                             (command, rc, reason))

        return (stdout, stderr, rc)


class _VM(object):
    """Windows Virtual Machine"""
    def __init__(self, disk, serial, params):
        """Create _VM instance

            disk: VM's hard disk
            serial: File to save the output of the serial port
        """

        self.disk = disk
        self.serial = serial
        self.params = params

        def random_mac():
            """creates a random mac address"""
            mac = [0x00, 0x16, 0x3e,
                   random.randint(0x00, 0x7f),
                   random.randint(0x00, 0xff),
                   random.randint(0x00, 0xff)]

            return ':'.join(['%02x' % x for x in mac])

        # Use ganeti's VNC port range for a random vnc port
        self.display = random.randint(11000, 14999) - 5900

        kvm = get_kvm_binary()

        if kvm is None:
            FatalError("Can't find the kvm binary")

        args = [
            kvm, '-smp', '1', '-m', '1024', '-drive',
            'file=%s,format=raw,cache=unsafe,if=virtio' % self.disk,
            '-netdev', 'type=user,hostfwd=tcp::445-:445,id=netdev0',
            '-device', 'virtio-net-pci,mac=%s,netdev=netdev0' % random_mac(),
            '-vnc', ':%d' % self.display, '-serial', 'file:%s' % self.serial,
            '-monitor', 'stdio']

        self.process = subprocess.Popen(args, stdin=subprocess.PIPE,
                                        stdout=subprocess.PIPE)

    def isalive(self):
        """Check if the VM is still alive"""
        return self.process.poll() is None

    def destroy(self):
        """Destroy the VM"""

        if not self.isalive():
            return

        def handler(signum, frame):
            self.process.terminate()
            time.sleep(1)
            if self.isalive():
                self.process.kill()
            self.process.wait()
            raise FatalError("VM destroy timed-out")

        signal.signal(signal.SIGALRM, handler)

        signal.alarm(self.params['shutdown_timeout'])
        self.process.communicate(input="system_powerdown\n")
        signal.alarm(0)

    def wait(self, timeout=0):
        """Wait for the VM to terminate"""

        def handler(signum, frame):
            self.destroy()
            raise FatalError("VM wait timed-out.")

        signal.signal(signal.SIGALRM, handler)

        signal.alarm(timeout)
        stdout, stderr = self.process.communicate()
        signal.alarm(0)

        return (stdout, stderr, self.process.poll())

# vim: set sta sts=4 shiftwidth=4 sw=4 et ai :