Whonix Windows Installer - Design Documentation

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The Whonix Windows Installer was designed as a simple and fast way to set-up Whonix on a system running Microsoft Windows.

Design / Features[edit]

WhonixStarter(.exe):

  • new implementation of whonix.exe in lazarus (without NET framework)
  • platform independent ( later linux/mac version possible )
  • ui consists of two forms ( main & error )
  • main form has two buttons for start/stop and manage Whonix VMs
  • error form pops up if virtualbox is missing

WhonixStarterSetup.msi:

  • installs windows version of WhonixStarter
  • adds start menu entry
  • adds desktop shortcut
  • uninstall over Windows "Programs and Features" tool

WhonixSetup(.exe):

  • ui consists of a main form with several pages guiding the user through the installation process
  • platform independent ( later linux/mac version possible )
  • installs VirtualBox and WhonixOVA
  • executes WhonixStarterSetup.msi (Windows only)
  • checks installed and only reinstall missing components
  • does not uninstall or delete any component

Challenges:

  • Whonix .ova is bigger than 2 GB.
  • Windows .cab files have a hardcoded 2 GB maximum file size.

Requirements:

  • cross compile on Debian (source) for Windows (target)
  • building does not require Windows

Build limitations:

  • needs Debian bookworm or above because of minimal wixl and lazarus version

flow chart[edit]

(1) Whonix-Starter:

  • lazbuild → WhonixStarter.lpr → WhonixStarter.exe
  • wixl → WhonixStarterSetup.wxs → WhonixStarter.exe, WhonixStarterSetup.wxs → WhonixStarterSetup.msi

(2) Whonix-Installer:

  • lazbuild → WhonixSetup.lpr → WhonixSetup.exe
  • WhonixSetup.exe + append + Whonix.ova → WhonixSetup-Xfce.exe

misc[edit]

Notes[edit]

UseVersionInfo WhonixSetup.lpi[edit]

Can the following variables be removed if not essential? 

OriginalFilename="WhonixInstaller-XYZ-1.2.3.4.exe"

      <UseVersionInfo Value="True"/>
      <MajorVersionNr Value="1"/>

The variables aren't essential for functionality.

For reasons of end user confidence it's recommended to keep the version and file information (<UseVersionInfo Value="True"/>).

"OriginalFilename" could just be "WhonixInstaller.exe". ( but I like to set the same as the final filename displayed in file browser )

"MajorVersionNr", "MinorVersionNr", "RevisionNr", "BuildNr" is summarized as "FileVersion" by Lazarus. If we delete these values the file version will be 0.0.0.0

I'm not sure in this case if the version refers to the installer or the software being installed.

CI[edit]

Whonix-Starter:

Whonix-Installer:

code signing[edit]

Introduction[edit]

EV (extended validation) certificate required to avoid Microsoft SmartScreen Filter warning message.

requirements[edit]

  • EV code signing for Windows Kicksecure logo authenticode Onion Version to avoid Microsoft SmartScreen Filter warning message.
  • cross signing
  • build scripts running on Debian Linux
  • build result (program) running on Windows 64 bit
  • avoid running proprietary closed source software on local build machine
  • can be fully automated using build scripts
  • avoid hardware token (compatibility, hassle)
  • avoid proprietary closed source device drivers
  • ideally avoid non-mainline Linux kernel drivers
  • supports signing big files

providers[edit]

thalesgroup:

  • asked. does not have Linux tools.

Certum:

sectigo:

certerassl:

ssl.com:

Google Cloud HSM;

Verification of Code Signing Process[edit]

Verification of VirtualBox[edit]

VirtualBox for Windows is signed using Microsoft Kicksecure logo Authenticode Onion Version signatures ("signtool").

VirtualBox's digital signature can be verified on the Linux platform using osslsigncode. Example:

osslsigncode verify -in VirtualBox-*.exe

A script verifyarchive.org has been added to the virtualbox-windows-installer-binary repository as a reminder and example how to verify the digital software signatures on the Linux platform.

Signing Whonix Windows Installer[edit]

This document is based on a case where an executable (hello.exe) is signed using GitHub Actions (CI) and CodeSigner.

For more details on the test, please refer to this GitHub repository: https://github.com/adrelanos/codesigner-testarchive.org

When a file (hello.exe) is signed, creating hello_signed.exe, the goal is to ensure that no additional modifications, beyond the signing process, have occurred. These could potentially include the insertion of malicious code.

Overview:

  • Original file: hello.exe
  • Signed file: hello_signed.exe
  • Extracted signature file: hello_signature.pem
  • File with reattached signature: hello_with_signature.exe
  • File with reattached signature and reset PE header: hello_with_signature_reset_PE.exe
  • File with removed signature: hello_without_signature.exe
  • File with removed signature and reset PE header: hello_without_signature_reset_PE.exe
  • pe-header-to-zeroarchive.org

To achieve this, the original file is compared with the signed file in various stages and through different methods. The key stages are as follows:

1. Extract the signature from the signed file using osslsigncode:

osslsigncode extract-signature -in hello_signed.exe -out hello_signature.pem

2. The original file (hello.exe) is then re-signed using this extracted signature to create a new file (hello_with_signature.exe):

osslsigncode attach-signature -sigin hello_signature.pem -in hello.exe -out hello_with_signature.exe

At this point, one would expect hello_signed.exe to be identical to hello_with_signature.exe. However, it was discovered that the signing process (osslsigncode attach-signature) modified the PE header of the file by adding a PE checksum, thus resulting in a difference between these two files.

To analyze and understand these differences, a set of tools were used, including diff, vbindiff, diffoscope, and readpe. These comparisons brought to light the change in the PE checksum.

3. In order to make a direct comparison, the PE checksum in hello_with_signature.exe was reset to 0, mirroring its original state in hello.exe and hello_signed.exe. This was achieved using a Python script named pe-header-to-zero:

pe-header-to-zero hello_with_signature.exe hello_with_signature_reset_PE.exe

After running this script, the newly created file hello_with_signature_reset_PE.exe was found to be an exact match to hello_signed.exe.

4. The script pe-header-to-zero was also used on hello_without_signature.exe to create hello_without_signature_reset_PE.exe:

pe-header-to-zero hello_without_signature.exe hello_without_signature_reset_PE.exe

It was found that hello_without_signature_reset_PE.exe was an exact match to the original hello.exe, further validating the process.

Following this thorough examination, it can be reasonably stated that the signing process did not introduce any unwanted or malicious modifications to the original executable file.

All operations were performed using the osslsigncode tool.

To install and examine PE headers, the pev tool was used:

sudo apt install pev

To view the PE checksum, the readpe utility was used:

readpe hello_signed.exe

readpe hello_with_signature_reset_PE.exe

readpe hello_without_signature_reset_PE.exe

Archived Tasks[edit]

WhonixStarter.msi execution[edit]

Happening on Windows 10. 

Step 9 / 9 : Installing Whonix-Starter...
Execute: msiexec /i "C:\Users\user\AppData\Local\Whonix-Xfce-17.2.0.1\WhonixStarter.msi"
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
Error : Whonix-Starter could not be installed.

-> fixed: see https://github.com/einsiedler90/Whonix-Installer/commit/5e52d6fc436001345db896ffee2f89c8b20c0ab1archive.org

Debugging Attempt 1: Double Clicking WhonixStarter.msi

While this happened, user kept the Whonix-Installer open and then attempted to manually run C:\Users\user\AppData\Local\Whonix-Xfce-17.2.0.1\WhonixStarter.msi for debugging reasons. Result: 

WhonixStarter

Another installation in progress. You must complete that installation before continuing this one.

Retry | Cancel

What can we conclude from this? Maybe while Whonix installer is running, it cannot execute msiexec /i "C:\Users\user\AppData\Local\Whonix-Xfce-17.2.0.1\WhonixStarter.msi" because it is blocking itself?

-> perhaps obsolete due to previous fix? Strange: execution of "msiexec" is finnished when "Whonix-Starter could not be installed." appears.

Debugging Attempt 2: Starting WhonixStarter.msi from Terminal

Starting msiexec /i "C:\Users\user\AppData\Local\Whonix-Xfce-17.2.0.1\WhonixStarter.msi" from terminal does not show any additional output.

TODO[edit]

merge[edit]

Reminder: Always please merge first before developing further.

update this wiki page[edit]

Please add comments to this wiki page once any things have been changed.

document debug mode[edit]

startup in debug mode

to use the debug mode just type in "--debug" behind the executable when startup with console.

false-positive installation failure error[edit]

See screenshot provided.

tell user there is a debug mode in the show installation details box[edit]

done: https://github.com/einsiedler90/Whonix-Installer/commit/175a005ad08088039e81346ee34db191529606ecarchive.org

tell user where to find the log file in the show installation details box[edit]

obsolete, as a separate log file is no longer needed at the moment.

Microsoft Visual C++ 2019 Redistributable Package Error[edit]

Microsoft Visual C++ 2019 Redistributable Package Error

  • Integrate vc_redist.x64.exe into the installer.
  • Installer can assume vc_redist.x64.exe is already on the hard drive. (No automated download from the internet.)
  • Please check if installed.¹
  • If not installed, install.¹

https://learn.microsoft.com/en-us/cpp/windows/latest-supported-vc-redist?view=msvc-170archive.org

https://aka.ms/vs/17/release/vc_redist.x64.exearchive.org

done. see: https://github.com/einsiedler90/Whonix-Installer/commit/df9ad3e91f48958fc48f30a8323e547bb4c87bd4archive.org ¹vc_redist.x64.exe checks itself so no separate check is needed.

rename setup to installer - update #3[edit]

file: Whonix-Installer build-dummy.sh 

export FILE_INSTALLER_BINARY_FINAL=~/windows-installer-dummy-temp-delete-me/WhonixSetup-$VERSION_FULL.exe

Please don't name "setup" because not using that word anywhere else.

fixed: see https://github.com/einsiedler90/Whonix-Installer/commit/4fea32191c48e7df75e70fda00e5d3947c8ee105archive.org

do not delete WhonixStarter.msi after installation[edit]

A user reported that WhonixStarter.msi gets deleted once Whonix installer gets closed.

If possible, please do not delete WhonixStarter.msi after installation. Why? To make this process easier to debug.

--> added "--debug" command line option to solve the problem.

see: https://github.com/einsiedler90/Whonix-Installer/commit/9a27e7f7194afa82da12cd4597e87144594e843earchive.org

Instructions for AI based Code Review[edit]

If the AI is talking trash, just delete it from the wiki without comment. No need to comment on AI generated text which is nonsense.

Please delete this wiki chapter now.

Claude AI based Code Review of whonixinstaller_main.pas[edit]

1) Resource management: While the code does free some resources, it's not consistent. For instance, in the FormCreate method, ResourceStream is created and freed, but in some other places like InstallationBuildIn, resources aren't always explicitly freed.

2) Potential infinite loop: In FormCreate, there's a while loop checking for disk space. If the user keeps selecting invalid directories, this could potentially become an infinite loop.

3) Unused variables: There are some unused variables in the code, like filename in the commented-out EnsureValidExePath procedure.

4) Inconsistent use of string types: The code mixes string and AnsiString types, which could lead to encoding issues.

5) Lack of input validation: When executing external commands, there's little to no validation of input parameters, which could potentially be a security risk.

6) UI responsiveness: The code uses Sleep in the SetNextStatus method, which could make the UI less responsive. Consider using a timer or async operations instead.

7) Incomplete implementation: Some methods like LabelCompleteDescClick are empty, suggesting incomplete functionality.

ChatGPT AI based Code Review of whonixinstaller_main.pas[edit]

Thread Blocking Due to Sleep and Application.ProcessMessages[edit]

In WhonixUtils.pas, Execute uses Sleep and Application.ProcessMessages in a loop, which can lead to a blocking UI: 

repeat
  Sleep(100);
  Application.ProcessMessages;
  ...
until (BytesRead = 0) and not Running;

Solution: Consider using a separate thread for executing processes to avoid blocking the main UI thread.

Answer from Developer: Any longer loop without "Application.ProcessMessages;" lead to a blocking UI. That's what the function is there for, to keep the UI responsive if the program is only single threaded. A separate thread is an alternative solution but it takes a few hours for some restructuring. This would also allow the installer logic to be separated more cleanly from the installer GUI. Please add a TODO if you want me to implement this.

Potential Memory Leaks[edit]

There are several places where dynamically allocated resources may not be freed properly in case of an exception, especially in FormCreate and InstallationBuildIn.

Solution: Use try-finally blocks to ensure that resources are properly freed: 

ResourceStream := TResourceStream.Create(HInstance, 'LICENSE', RT_RCDATA);
try
  MemoLicense.Lines.LoadFromStream(ResourceStream);
finally
  ResourceStream.Free;
end;

Answer from Developer: In most cases with dynamic data this is correct, but this code only loads static content from the program resources (license text) which is always present (except by any errors while compile time), so I have omitted the “try finally” for shorter code.

Deprecation and Error Handling[edit]

Deprecated code comments indicate potential areas that might be out of date: 

// deprecated??? ---------------------->
if not InstallerForm.Showing then
begin
  InstallerForm.Show;
end;
// ------------------------------------<

Solution: Review and update the deprecated code.

done. https://github.com/einsiedler90/Whonix-Installer/commit/8ec3962f94a6610436219a2666ffb4eecc62cd20archive.org

More ChatGPT AI based Review[edit]

https://chatgpt.com/archive.org

1) Please register a free account.

2) Write "any bugs?" followed by a copy/paste of 1 source code file.

3) Ignore wrong/useless/overboard comments and address any useful comments.

More Claude AI based Review[edit]

https://claude.aiarchive.org

Similar to above.

Windows_User_Interface wiki page[edit]

TODO: update/rewrite Dev/Windows_Starter

See Also[edit]

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