Ubuntu Manpage: virt-win-reg - Export and merge Windows Registry entries from a Windows guest

Provided by: libguestfs-tools_1.40.2-7ubuntu5_amd64

NAME

       virt-win-reg - Export and merge Windows Registry entries from a Windows guest

SYNOPSIS

        virt-win-reg domname 'HKLM\Path\To\Subkey'

        virt-win-reg domname 'HKLM\Path\To\Subkey' name

        virt-win-reg domname 'HKLM\Path\To\Subkey' @

        virt-win-reg --merge domname [input.reg ...]

        virt-win-reg [--options] disk.img ... # instead of domname

WARNING

       You must not use "virt-win-reg" with the --merge option on live virtual machines.  If you do this, you
       will get irreversible disk corruption in the VM.  "virt-win-reg" tries to stop you from doing this, but
       doesn't catch all cases.

       Modifying the Windows Registry is an inherently risky operation.  The format is deliberately obscure and
       undocumented, and Registry changes can leave the system unbootable.  Therefore when using the --merge
       option, make sure you have a reliable backup first.

DESCRIPTION

       This program can export and merge Windows Registry entries from a Windows guest.

       The first parameter is the libvirt guest name or the raw disk image of a Windows guest.

       If --merge is not specified, then the chosen registry key is displayed/exported (recursively).  For
       example:

        $ virt-win-reg Windows7 'HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft'

       You can also display single values from within registry keys, for example:

        $ cvkey='HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion'
        $ virt-win-reg Windows7 $cvkey ProductName
        Windows 7 Enterprise

       With --merge, you can merge a textual regedit file into the Windows Registry:

        $ virt-win-reg --merge Windows7 changes.reg

   NOTE
       This program is only meant for simple access to the registry.  If you want to do complicated things with
       the registry, we suggest you download the Registry hive files from the guest using libguestfs(3) or
       guestfish(1) and access them locally, eg. using hivex(3), hivexsh(1) or hivexregedit(1).

OPTIONS

--help
Display brief help.

--version
Display version number and exit.

--debug
Enable debugging messages.

-c URI
--connect URI
If using libvirt, connect to the given URI. If omitted, then we connect to the default libvirt
hypervisor.

If you specify guest block devices directly, then libvirt is not used at all.

--format raw
Specify the format of disk images given on the command line. If this is omitted then the format is
autodetected from the content of the disk image.

If disk images are requested from libvirt, then this program asks libvirt for this information. In
this case, the value of the format parameter is ignored.

If working with untrusted raw-format guest disk images, you should ensure the format is always
specified.

--merge
In merge mode, this merges a textual regedit file into the Windows Registry of the virtual machine.
If this flag is not given then virt-win-reg displays or exports Registry entries instead.

Note that --merge is unsafe to use on live virtual machines, and will result in disk corruption.
However exporting (without this flag) is always safe.

--encoding UTF-16LE|ASCII
When merging (only), you may need to specify the encoding for strings to be used in the hive file.
This is explained in detail in "ENCODING STRINGS" in Win::Hivex::Regedit(3).

The default is to use UTF-16LE, which should work with recent versions of Windows.

--unsafe-printable-strings
When exporting (only), assume strings are UTF-16LE and print them as strings instead of hex
sequences. Remove the final zero codepoint from strings if present.

This is unsafe and does not preserve the fidelity of strings in the original Registry for various
reasons:

• Assumes the original encoding is UTF-16LE. ASCII strings and strings in other encodings will be
corrupted by this transformation.

• Assumes that everything which has type 1 or 2 is really a string and that everything else is not
a string, but the type field in real Registries is not reliable.

• Loses information about whether a zero codepoint followed the string in the Registry or not.

This all happens because the Registry itself contains no information about how strings are encoded
(see "ENCODING STRINGS" in Win::Hivex::Regedit(3)).

You should only use this option for quick hacking and debugging of the Registry contents, and never
use it if the output is going to be passed into another program or stored in another Registry.

SUPPORTED SYSTEMS

       The program currently supports Windows NT-derived guests starting with Windows XP through to at least
       Windows 8.

       The following Registry keys are supported:

       "HKEY_LOCAL_MACHINE\SAM"
       "HKEY_LOCAL_MACHINE\SECURITY"
       "HKEY_LOCAL_MACHINE\SOFTWARE"
       "HKEY_LOCAL_MACHINE\SYSTEM"
       "HKEY_USERS\.DEFAULT"
       "HKEY_USERS\SID"
           where SID is a Windows User SID (eg. "S-1-5-18").

       "HKEY_USERS\username"
           where username is a local user name (this is a libguestfs extension).

       You can use "HKLM" as a shorthand for "HKEY_LOCAL_MACHINE", and "HKU" for "HKEY_USERS".

       The literal keys "HKEY_USERS\$SID" and "HKEY_CURRENT_USER" are not supported (there is no "current
       user").

   WINDOWS 8
       Windows 8 "fast startup" can prevent virt-win-reg from being able to edit the Registry.  See "WINDOWS
       HIBERNATION AND WINDOWS 8 FAST STARTUP" in guestfs(3).

ENCODING

       "virt-win-reg" expects that regedit files have already been reencoded in the local encoding.  Usually on
       Linux hosts, this means UTF-8 with Unix-style line endings.  Since Windows regedit files are often in
       UTF-16LE with Windows-style line endings, you may need to reencode the whole file before or after
       processing.

       To reencode a file from Windows format to Linux (before processing it with the --merge option), you would
       do something like this:

        iconv -f utf-16le -t utf-8 < win.reg | dos2unix > linux.reg

       To go in the opposite direction, after exporting and before sending the file to a Windows user, do
       something like this:

        unix2dos linux.reg | iconv -f utf-8 -t utf-16le > win.reg

       For more information about encoding, see Win::Hivex::Regedit(3).

       If you are unsure about the current encoding, use the file(1) command.  Recent versions of Windows
       regedit.exe produce a UTF-16LE file with Windows-style (CRLF) line endings, like this:

        $ file software.reg
        software.reg: Little-endian UTF-16 Unicode text, with very long lines,
        with CRLF line terminators

       This file would need conversion before you could --merge it.

CurrentControlSet etc.

       Registry keys like "CurrentControlSet" don’t really exist in the Windows Registry at the level of the
       hive file, and therefore you cannot modify these.

       "CurrentControlSet" is usually an alias for "ControlSet001".  In some circumstances it might refer to
       another control set.  The way to find out is to look at the "HKLM\SYSTEM\Select" key:

        # virt-win-reg WindowsGuest 'HKLM\SYSTEM\Select'
        [HKEY_LOCAL_MACHINE\SYSTEM\Select]
        "Current"=dword:00000001
        "Default"=dword:00000001
        "Failed"=dword:00000000
        "LastKnownGood"=dword:00000002

       "Current" is the one which Windows will choose when it boots.

       Similarly, other "Current..." keys in the path may need to be replaced.

DELETING REGISTRY KEYS AND VALUES

       To delete a whole registry key, use the syntax:

        [-HKEY_LOCAL_MACHINE\Foo]

       To delete a single value within a key, use the syntax:

        [HKEY_LOCAL_MACHINE\Foo]
        "Value"=-

WINDOWS TIPS

Note that some of these tips modify the guest disk image. The guest must be shut off, else you will get
disk corruption.

RUNNING A BATCH SCRIPT WHEN A USER LOGS IN
Prepare a DOS batch script, VBScript or executable. Upload this using guestfish(1). For this example
the script is called "test.bat" and it is uploaded into "C:\":

guestfish -i -d WindowsGuest upload test.bat /test.bat

Prepare a regedit file containing the registry change:

cat > test.reg <<'EOF'
[HKLM\Software\Microsoft\Windows\CurrentVersion\RunOnce]
"Test"="c:\\test.bat"
EOF

In this example we use the key "RunOnce" which means that the script will run precisely once when the
first user logs in. If you want it to run every time a user logs in, replace "RunOnce" with "Run".

Now update the registry:

virt-win-reg --merge WindowsGuest test.reg

INSTALLING A SERVICE
This section assumes you are familiar with Windows services, and you either have a program which handles
the Windows Service Control Protocol directly or you want to run any program using a service wrapper like
SrvAny or the free RHSrvAny.

First upload the program and optionally the service wrapper. In this case the test program is called
"test.exe" and we are using the RHSrvAny wrapper:

guestfish -i -d WindowsGuest <<EOF
upload rhsrvany.exe /rhsrvany.exe
upload test.exe /test.exe
EOF

Prepare a regedit file containing the registry changes. In this example, the first registry change is
needed for the service itself or the service wrapper (if used). The second registry change is only
needed because I am using the RHSrvAny service wrapper.

cat > service.reg <<'EOF'
[HKLM\SYSTEM\ControlSet001\services\RHSrvAny]
"Type"=dword:00000010
"Start"=dword:00000002
"ErrorControl"=dword:00000001
"ImagePath"="c:\\rhsrvany.exe"
"DisplayName"="RHSrvAny"
"ObjectName"="NetworkService"

[HKLM\SYSTEM\ControlSet001\services\RHSrvAny\Parameters]
"CommandLine"="c:\\test.exe"
"PWD"="c:\\Temp"
EOF

Notes:

• For use of "ControlSet001" see the section above in this manual page. You may need to adjust this
according to the control set that is in use by the guest.

• "ObjectName" controls the privileges that the service will have. An alternative is
"ObjectName"="LocalSystem" which would be the most privileged account.

• For the meaning of the magic numbers, see this Microsoft KB article:
http://support.microsoft.com/kb/103000.

Update the registry:

virt-win-reg --merge WindowsGuest service.reg

SHELL QUOTING

       Be careful when passing parameters containing "\" (backslash) in the shell.  Usually you will have to use
       'single quotes' or double backslashes (but not both) to protect them from the shell.

       Paths and value names are case-insensitive.

AUTHOR

       Richard W.M. Jones http://people.redhat.com/~rjones/

COPYRIGHT

       Copyright (C) 2010 Red Hat Inc.

LICENSE

       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.

BUGS

       To get a list of bugs against libguestfs, use this link:
       https://bugzilla.redhat.com/buglist.cgi?component=libguestfs&product=Virtualization+Tools

       To report a new bug against libguestfs, use this link:
       https://bugzilla.redhat.com/enter_bug.cgi?component=libguestfs&product=Virtualization+Tools

       When reporting a bug, please supply:

       •   The version of libguestfs.

       •   Where you got libguestfs (eg. which Linux distro, compiled from source, etc)

       •   Describe the bug accurately and give a way to reproduce it.

       •   Run libguestfs-test-tool(1) and paste the complete, unedited output into the bug report.