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14 changed files with 84 additions and 272 deletions

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@ -6,7 +6,7 @@ WFVM
A Nix library to create and manage virtual machines running Windows, a medieval operating system found on most computers in 2020. The F stands for "Functional" or a four-letter word of your choice.
* Reproducible - everything runs in the Nix sandbox with no tricks.
* Fully automatic, parameterizable Windows 11 installation.
* Fully automatic, parameterizable Windows 10 installation.
* Uses QEMU with KVM.
* Supports incremental installation (using "layers") of additional software via QEMU copy-on-write backing chains. For example, ``wfvm.makeWindowsImage { installCommands = [ wfvm.layers.anaconda3 ]; };`` gives you a VM image with Anaconda3 installed, and ``wfvm.makeWindowsImage { installCommands = [ wfvm.layers.anaconda3 wfvm.layers.msys2 ]; };`` gives you one with both Anaconda3 and MSYS2 installed. The base Windows installation and the Anaconda3 data are shared between both images, and only the MSYS2 installation is performed when building the second image after the first one has been built.
* Included layers: Anaconda3, a software installer chock full of bugs that pretends to be a package manager, Visual Studio, a spamming system for Microsoft accounts that includes a compiler, and MSYS2, which is the only sane component in the whole lot.
@ -52,30 +52,3 @@ Impure/pure mode
Sometimes it can be useful to build the image _outside_ of the Nix sandbox for debugging purposes.
For this purpose we have an attribute called `impureMode` which outputs the shell script used by Nix inside the sandbox to build the image.
Usage with Nix Flakes
---------------------
Build the demo by running:
```shell
nix build .#demoImage
```
This project's **flake.nix** exposes its functions under `lib`. To use
in your own project, setup your flake like this:
```nix
{
inputs = {
nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
wfvm.url = "git+https://git.m-labs.hk/m-labs/wfvm";
};
outputs = { self, nixpkgs, wfvm }: {
packages."x86_64-linux".flaky-os = wfvm.lib.makeWindowsImage {
# configuration parameters go here
};
};
}
```

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@ -1,27 +0,0 @@
{
"nodes": {
"nixpkgs": {
"locked": {
"lastModified": 1685004253,
"narHash": "sha256-AbVL1nN/TDicUQ5wXZ8xdLERxz/eJr7+o8lqkIOVuaE=",
"owner": "NixOS",
"repo": "nixpkgs",
"rev": "3e01645c40b92d29f3ae76344a6d654986a91a91",
"type": "github"
},
"original": {
"owner": "NixOS",
"ref": "nixos-23.05",
"repo": "nixpkgs",
"type": "github"
}
},
"root": {
"inputs": {
"nixpkgs": "nixpkgs"
}
}
},
"root": "root",
"version": 7
}

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@ -1,37 +0,0 @@
{
description = "WFVM: Windows Functional Virtual Machine";
inputs = {
nixpkgs.url = "github:NixOS/nixpkgs/nixos-23.05";
};
outputs = { self, nixpkgs }:
let
# only x64 is supported
system = "x86_64-linux";
pkgs = nixpkgs.legacyPackages.${system};
in rec {
lib = import ./wfvm {
inherit pkgs;
};
packages.${system} = rec {
demoImage = import ./wfvm/demo-image.nix {
inherit self;
};
default = lib.utils.wfvm-run {
name = "demo";
image = demoImage;
script =
''
echo "Windows booted. Press Enter to terminate VM."
read
'';
display = true;
};
};
};
}

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@ -15,8 +15,6 @@
, impureShellCommands ? []
, driveLetter ? "D:"
, efi ? true
, imageSelection ? "Windows 11 Pro N"
, enableTpm
, ...
}:
@ -51,28 +49,34 @@ let
# mkDirsDesc ++ writeKeysDesc ++
[
{
Path = ''powershell.exe ${driveLetter}\install-ssh.ps1'';
Description = "Install OpenSSH service.";
Path = ''powershell.exe Add-WindowsCapability -Online -Name OpenSSH.Server~~~~0.0.1.0 -Source ${driveLetter}\fod -LimitAccess'';
Description = "Add OpenSSH service.";
}
{
Path = ''powershell.exe Set-Service -Name sshd -StartupType Automatic'';
Description = "Enable SSH by default.";
}
];
assertCommand = c: builtins.typeOf c == "string" || builtins.typeOf c == "set" && builtins.hasAttr "Path" c && builtins.hasAttr "Description" c;
commands = builtins.map (x: assert assertCommand x; if builtins.typeOf x == "string" then { Path = x; Description = x; } else x) (
[ {
[
{
Path = "powershell.exe Set-ExecutionPolicy -Force Unrestricted";
Description = "Allow unsigned powershell scripts.";
} {
}
]
++ [
{
Path = ''powershell.exe ${driveLetter}\win-bundle-installer.exe'';
Description = "Install any declared packages.";
} {
Path = "net accounts /maxpwage:unlimited";
Description = "Disable forced password expiry.";
} ]
}
]
++ setupCommands
++ [
{
Path = ''powershell.exe ${driveLetter}\setup.ps1'';
Path = ''powershell.exe ${driveLetter}\ssh-setup.ps1'';
Description = "Setup SSH and keys";
}
]
@ -147,14 +151,6 @@ let
</DriverPaths>
</component>
<component name="Microsoft-Windows-Setup" processorArchitecture="amd64" publicKeyToken="31bf3856ad364e35" language="neutral" versionScope="nonSxS" xmlns:wcm="http://schemas.microsoft.com/WMIConfig/2002/State" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
${lib.optionalString (!enableTpm) ''
<RunSynchronous>
<RunSynchronousCommand wcm:action="add">
<Order>1</Order>
<Path>reg add HKLM\System\Setup\LabConfig /v BypassTPMCheck /t reg_dword /d 0x00000001 /f</Path>
</RunSynchronousCommand>
</RunSynchronous>
''}
<DiskConfiguration>
<Disk wcm:action="add">
@ -206,10 +202,9 @@ let
<PartitionID>3</PartitionID>
</InstallTo>
<InstallFrom>
<Path>\install.swm</Path>
<MetaData wcm:action="add">
<Key>/IMAGE/NAME</Key>
<Value>${imageSelection}</Value>
<Key>/IMAGE/INDEX</Key>
<Value>1</Value>
</MetaData>
</InstallFrom>
</OSImage>
@ -217,7 +212,7 @@ let
<UserData>
<ProductKey>
${if productKey != null then "<Key>${productKey}</Key>" else "<Key/>"}
${if productKey != null then "<Key>${productKey}</Key>" else ""}
<WillShowUI>OnError</WillShowUI>
</ProductKey>
<AcceptEula>true</AcceptEula>
@ -307,18 +302,18 @@ let
</component>
</settings>
<cpi:offlineImage cpi:source="wim:c:/wim/windows-11/install.wim#${imageSelection}" xmlns:cpi="urn:schemas-microsoft-com:cpi" />
<cpi:offlineImage cpi:source="wim:c:/wim/windows-10/install.wim#Windows 10 Enterprise LTSC 2019 Evaluation" xmlns:cpi="urn:schemas-microsoft-com:cpi" />
</unattend>
'';
in {
# Lint and format as a sanity check
autounattendXML = pkgs.runCommand "autounattend.xml" {} ''
autounattendXML = pkgs.runCommandNoCC "autounattend.xml" {} ''
${pkgs.libxml2}/bin/xmllint --format ${autounattendXML} > $out
'';
# autounattend.xml is _super_ picky about quotes and other things
setupScript = pkgs.writeText "setup.ps1" (
setupScript = pkgs.writeText "ssh-setup.ps1" (
''
# Setup SSH and keys
'' +

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@ -1,10 +1,7 @@
{ pkgs }:
pkgs.runCommand "win-bundle-installer.exe" {} ''
mkdir bundle
cd bundle
cp ${./go.mod} go.mod
pkgs.runCommandNoCC "win-bundle-installer.exe" {} ''
cp ${./main.go} main.go
env HOME=$(mktemp -d) GOOS=windows GOARCH=amd64 ${pkgs.go}/bin/go build
mv bundle.exe $out
mv build.exe $out
''

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@ -1,3 +0,0 @@
module bundle
go 1.11

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@ -2,6 +2,6 @@
{
makeWindowsImage = attrs: import ./win.nix ({ inherit pkgs; } // attrs);
layers = import ./layers { inherit pkgs; };
utils = import ./utils.nix { inherit pkgs; };
layers = (import ./layers { inherit pkgs; });
utils = (import ./utils.nix { inherit pkgs; });
}

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@ -1,27 +1,16 @@
{ pkgs ? import <nixpkgs> {}
# Whether to generate just a script to start and debug the windows installation
, impureMode ? false
# Flake input `self`
, self ? null
}:
{ pkgs ? import <nixpkgs> {}, impureMode ? false }:
let
wfvm =
if self == null
# nix-build
then (import ./default.nix { inherit pkgs; })
# built from flake.nix
else self.lib;
wfvm = (import ./default.nix { inherit pkgs; });
in
wfvm.makeWindowsImage {
# Build install script & skip building iso
inherit impureMode;
# Custom base iso
# windowsImage = pkgs.requireFile rec {
# name = "Win11_22H2_English_x64v1.iso";
# sha256 = "08mbppsm1naf73z8fjyqkf975nbls7xj9n4fq0yp802dv1rz3whd";
# message = "Get disk image ${name} from https://www.microsoft.com/en-us/software-download/windows11/";
# windowsImage = pkgs.fetchurl {
# url = "https://software-download.microsoft.com/download/sg/17763.107.101029-1455.rs5_release_svc_refresh_CLIENT_LTSC_EVAL_x64FRE_en-us.iso";
# sha256 = "668fe1af70c2f7416328aee3a0bb066b12dc6bbd2576f40f812b95741e18bc3a";
# };
# impureShellCommands = [
@ -57,7 +46,7 @@ wfvm.makeWindowsImage {
disable-autolock
disable-firewall
])
anaconda3 msys2
anaconda3 msys2 msvc msvc-ide-unbreak
];
# services = {
@ -68,10 +57,8 @@ wfvm.makeWindowsImage {
# };
# };
# License key (required)
# productKey = throw "Search the f* web"
imageSelection = "Windows 11 Pro N";
# License key
# productKey = "iboughtthisone";
# Locales
# uiLanguage = "en-US";

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@ -1,42 +0,0 @@
Write-Host "Expanding OpenSSH"
Expand-Archive D:\OpenSSH-Win64.zip C:\
Push-Location C:\OpenSSH-Win64
Write-Host "Installing OpenSSH"
& .\install-sshd.ps1
Write-Host "Generating host keys"
.\ssh-keygen.exe -A
Write-Host "Fixing host file permissions"
& .\FixHostFilePermissions.ps1 -Confirm:$false
Write-Host "Fixing user file permissions"
& .\FixUserFilePermissions.ps1 -Confirm:$false
Pop-Location
$newPath = 'C:\OpenSSH-Win64;' + [Environment]::GetEnvironmentVariable("PATH", [EnvironmentVariableTarget]::Machine)
[Environment]::SetEnvironmentVariable("PATH", $newPath, [EnvironmentVariableTarget]::Machine)
#Write-Host "Adding public key to authorized_keys"
#$keyPath = "~\.ssh\authorized_keys"
#New-Item -Type Directory ~\.ssh > $null
#$sshKey | Out-File $keyPath -Encoding Ascii
Write-Host "Opening firewall port 22"
New-NetFirewallRule -Protocol TCP -LocalPort 22 -Direction Inbound -Action Allow -DisplayName SSH
Write-Host "Setting sshd service startup type to 'Automatic'"
Set-Service sshd -StartupType Automatic
Set-Service ssh-agent -StartupType Automatic
Write-Host "Setting sshd service restart behavior"
sc.exe failure sshd reset= 86400 actions= restart/500
#Write-Host "Configuring sshd"
#(Get-Content C:\ProgramData\ssh\sshd_config).replace('#TCPKeepAlive yes', 'TCPKeepAlive yes').replace('#ClientAliveInterval 0', 'ClientAliveInterval 300').replace('#ClientAliveCountMax 3', 'ClientAliveCountMax 3') | Set-Content C:\ProgramData\ssh\sshd_config
Write-Host "Starting sshd service"
Start-Service sshd
Start-Service ssh-agent

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@ -8,8 +8,8 @@ in
script = let
Anaconda3 = pkgs.fetchurl {
name = "Anaconda3.exe";
url = "https://repo.anaconda.com/archive/Anaconda3-2021.05-Windows-x86_64.exe";
sha256 = "1lpk7k4gydyk524z1nk4rrninrwi20g2ias2njc9w0a40hwl5nwk";
url = "https://repo.anaconda.com/archive/Anaconda3-2020.02-Windows-x86_64.exe";
sha256 = "0n31l8l89jrjrbzbifxbjnr3g320ly9i4zfyqbf3l9blf4ygbhl3";
};
in
''
@ -71,8 +71,8 @@ in
script = let
bootstrapper = pkgs.fetchurl {
name = "RESTRICTDIST-vs_Community.exe";
url = "https://aka.ms/vs/16/release/vs_community.exe";
sha256 = "sha256-l4ZKFZTgHf3BmD0eFWyGwsvb4lqB/LiQYizAABOs3gg=";
url = "https://download.visualstudio.microsoft.com/download/pr/ac05c4f5-0da1-429f-8701-ce509ac69926/cc9556137c66a373670376d6db2fc5c5c937b2b0bf7b3d3cac11c69e33615511/vs_Community.exe";
sha256 = "04amc4rrxihimhy3syxzn2r3gjf5qlpxpmkn0dkp78v6gh9md5fc";
};
# This touchy-feely "community" piece of trash seems deliberately crafted to break Wine, so we use the VM to run it.
download-vs = wfvm.utils.wfvm-run {
@ -93,7 +93,7 @@ in
outputHashAlgo = "sha256";
outputHashMode = "recursive";
outputHash = "sha256-GoOKzln8DXVMx52jWGEjwkOFkpSW+wEffAVmBVugIyk=";
outputHash = "0fp7a6prjp8n8sirwday13wis3xyzhmrwi377y3x89nxzysp0mnv";
phases = [ "buildPhase" ];
buildInputs = [ download-vs ];
@ -118,7 +118,7 @@ in
name = "MSVC-ide-unbreak";
script =
''
win-exec 'cd "C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\Common7\IDE" && devenv /ResetSettings'
win-exec 'cd "C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\Common7\IDE" && devenv /ResetSettings'
sleep 40
'';
};
@ -154,16 +154,6 @@ in
win-exec "reg add HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\Personalization /v NoLockScreen /t REG_DWORD /d 1"
'';
};
# Don't let Windows start completely rewriting gigabytes of disk
# space. Defragmentation increases the size of our qcow layers
# needlessly.
disable-scheduled-defrag = {
name = "disable-scheduled-defrag";
script = ''
echo Disabling scheduled defragmentation service
win-exec 'schtasks /Change /DISABLE /TN "\Microsoft\Windows\Defrag\ScheduledDefrag"'
'';
};
# Chain together layers that are quick to run so that the VM does
# not have to be started/shutdown for each.

1
wfvm/openssh/README.md Normal file
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@ -0,0 +1 @@
This file is not publicaly acessible anywhere so had to be extracted from a connected instance

Binary file not shown.

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@ -1,45 +1,23 @@
{ pkgs
, baseRtc ? "2022-10-10T10:10:10"
, cores ? "4"
, qemuMem ? "4G"
, efi ? true
, enableTpm ? false
, ...
}:
{ pkgs, baseRtc ? "2020-04-20T14:21:42", cores ? "4", qemuMem ? "4G", efi ? true }:
rec {
# qemu_test is a smaller closure only building for a single system arch
qemu = pkgs.qemu;
OVMF = pkgs.OVMF.override {
secureBoot = true;
};
qemu = pkgs.qemu_test;
mkQemuFlags = extraFlags: [
"-enable-kvm"
"-cpu host"
"-smp ${cores}"
"-m ${qemuMem}"
"-M q35,smm=on"
"-M q35"
"-vga qxl"
"-rtc base=${baseRtc}"
"-device qemu-xhci"
"-device virtio-net-pci,netdev=n1"
] ++ pkgs.lib.optionals efi [
"-bios ${OVMF.fd}/FV/OVMF.fd"
] ++ pkgs.lib.optionals enableTpm [
"-chardev" "socket,id=chrtpm,path=tpm.sock"
"-tpmdev" "emulator,id=tpm0,chardev=chrtpm"
"-device" "tpm-tis,tpmdev=tpm0"
"-bios ${pkgs.OVMF.fd}/FV/OVMF.fd"
] ++ extraFlags;
tpmStartCommands = pkgs.lib.optionalString enableTpm ''
mkdir -p tpmstate
${pkgs.swtpm}/bin/swtpm socket \
--tpmstate dir=tpmstate \
--ctrl type=unixio,path=tpm.sock &
'';
# Pass empty config file to prevent ssh from failing to create ~/.ssh
sshOpts = "-F /dev/null -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null -o LogLevel=ERROR -o ConnectTimeout=1";
win-exec = pkgs.writeShellScriptBin "win-exec" ''
@ -82,10 +60,8 @@ rec {
echo win-put $1 -\> $2
${pkgs.sshpass}/bin/sshpass -p1234 -- \
${pkgs.openssh}/bin/sftp -r -P 2022 ${sshOpts} \
wfvm@localhost -b- << EOF
cd $2
put $1
EOF
wfvm@localhost <<< "cd $2
put $1"
'';
win-get = pkgs.writeShellScriptBin "win-get" ''
set -e
@ -115,7 +91,6 @@ rec {
]);
in pkgs.writeShellScriptBin "wfvm-run-${name}" ''
set -e -m
${tpmStartCommands}
${qemu}/bin/qemu-system-x86_64 ${pkgs.lib.concatStringsSep " " qemuParams} &
${win-wait}/bin/win-wait

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@ -5,17 +5,16 @@
, impureMode ? false
, installCommands ? []
, users ? {}
, enableTpm ? true
# autounattend always installs index 1, so this default is backward-compatible
, imageSelection ? "Windows 11 Pro N"
, imageSelection ? "1"
, efi ? true
, ...
}@attrs:
let
lib = pkgs.lib;
utils = import ./utils.nix ({ inherit pkgs efi enableTpm; } // attrs);
inherit (pkgs) guestfs-tools;
utils = import ./utils.nix { inherit pkgs efi; };
libguestfs = pkgs.libguestfs-with-appliance;
# p7zip on >20.03 has known vulns but we have no better option
p7zip = pkgs.p7zip.overrideAttrs(old: {
@ -25,7 +24,7 @@ let
});
runQemuCommand = name: command: (
pkgs.runCommand name { buildInputs = [ p7zip utils.qemu guestfs-tools ]; }
pkgs.runCommandNoCC name { buildInputs = [ p7zip utils.qemu libguestfs ]; }
(
''
if ! test -f; then
@ -36,25 +35,23 @@ let
)
);
windowsIso = if windowsImage != null then windowsImage else pkgs.requireFile rec {
name = "Win11_22H2_English_x64v2.iso";
sha256 = "0xhhxy47yaf1jsfmskym5f65hljw8q0aqs70my86m402i6dsjnc0";
message = "Get disk image ${name} from https://www.microsoft.com/en-us/software-download/windows11/";
windowsIso = if windowsImage != null then windowsImage else pkgs.fetchurl {
name = "RESTRICTDIST-release_svc_refresh_CLIENT_LTSC_EVAL_x64FRE_en-us.iso";
url = "https://software-download.microsoft.com/download/sg/17763.107.101029-1455.rs5_release_svc_refresh_CLIENT_LTSC_EVAL_x64FRE_en-us.iso";
sha256 = "668fe1af70c2f7416328aee3a0bb066b12dc6bbd2576f40f812b95741e18bc3a";
};
# stable as of 2021-04-08
virtioWinIso = pkgs.fetchurl {
url = "https://fedorapeople.org/groups/virt/virtio-win/direct-downloads/archive-virtio/virtio-win-0.1.229-1/virtio-win.iso";
sha256 = "1q5vrcd70kya4nhlbpxmj7mwmwra1hm3x7w8rzkawpk06kg0v2n8";
url = "https://fedorapeople.org/groups/virt/virtio-win/direct-downloads/archive-virtio/virtio-win-0.1.185-2/virtio-win-0.1.185.iso";
sha256 = "11n3kjyawiwacmi3jmfmn311g9xvfn6m0ccdwnjxw1brzb4kqaxg";
};
openSshServerPackage = pkgs.fetchurl {
url = "https://github.com/PowerShell/Win32-OpenSSH/releases/download/V8.6.0.0p1-Beta/OpenSSH-Win64.zip";
sha256 = "1dw6n054r0939501dpxfm7ghv21ihmypdx034van8cl21gf1b4lz";
};
openSshServerPackage = ./openssh/server-package.cab;
autounattend = import ./autounattend.nix (
attrs // {
inherit pkgs enableTpm;
inherit pkgs;
users = users // {
wfvm = {
password = "1234";
@ -72,16 +69,17 @@ let
# Packages required to drive installation of other packages
bootstrapPkgs =
runQemuCommand "bootstrap-win-pkgs.img" ''
mkdir -p pkgs/fod
7z x -y ${virtioWinIso} -opkgs/virtio
cp ${bundleInstaller} pkgs/"$(stripHash "${bundleInstaller}")"
# Install optional windows features
cp ${openSshServerPackage} pkgs/OpenSSH-Win64.zip
cp ${openSshServerPackage} pkgs/fod/OpenSSH-Server-Package~31bf3856ad364e35~amd64~~.cab
# SSH setup script goes here because windows XML parser sucks
cp ${./install-ssh.ps1} pkgs/install-ssh.ps1
cp ${autounattend.setupScript} pkgs/setup.ps1
cp ${autounattend.setupScript} pkgs/ssh-setup.ps1
virt-make-fs --partition --type=fat pkgs/ $out
'';
@ -109,7 +107,7 @@ let
''
#!${pkgs.runtimeShell}
set -euxo pipefail
export PATH=${lib.makeBinPath [ p7zip utils.qemu guestfs-tools pkgs.wimlib ]}:$PATH
export PATH=${lib.makeBinPath [ p7zip utils.qemu libguestfs pkgs.wimlib ]}:$PATH
# Create a bootable "USB" image
# Booting in USB mode circumvents the "press any key to boot from cdrom" prompt
@ -119,10 +117,20 @@ let
mkdir -p win/nix-win
7z x -y ${windowsIso} -owin
# Split image so it fits in FAT32 partition
wimsplit win/sources/install.wim win/sources/install.swm 4070
# Extract desired variant from install.wim
# This is useful if the install.wim contains multiple Windows
# versions (e.g., Home, Pro, ..), because the autounattend file
# will always select index 1. With this mechanism, a variant different
# from the first one can be automatically selected.
# imageSelection can be either an index (1-N) or the image name
# wiminfo can list all images contained in a given WIM file
wimexport win/sources/install.wim "${imageSelection}" win/sources/install_selected.wim
rm win/sources/install.wim
# Split image so it fits in FAT32 partition
wimsplit win/sources/install_selected.wim win/sources/install.swm 4096
rm win/sources/install_selected.wim
cp ${autounattend.autounattendXML} win/autounattend.xml
${if efi then ''
@ -132,20 +140,18 @@ let
''}
rm -rf win
${utils.tpmStartCommands}
# Qemu requires files to be rw
qemu-img create -f qcow2 c.img ${diskImageSize}
qemu-system-x86_64 ${lib.concatStringsSep " " qemuParams}
''
);
baseImage = pkgs.runCommand "RESTRICTDIST-windows.img" {} ''
baseImage = pkgs.runCommandNoCC "RESTRICTDIST-windows.img" {} ''
${installScript}
mv c.img $out
'';
finalImage = builtins.foldl' (acc: v: pkgs.runCommand "RESTRICTDIST-${v.name}.img" {
finalImage = builtins.foldl' (acc: v: pkgs.runCommandNoCC "RESTRICTDIST-${v.name}.img" {
buildInputs = with utils; [
qemu win-wait win-exec win-put
] ++ (v.buildInputs or []);
@ -160,11 +166,8 @@ let
]);
in ''
set -x
${utils.tpmStartCommands}
# Create an image referencing the previous image in the chain
qemu-img create -F qcow2 -f qcow2 -b ${acc} c.img
qemu-img create -f qcow2 -b ${acc} c.img
set -m
qemu-system-x86_64 ${lib.concatStringsSep " " qemuParams} &