nixpkgs/nixos/modules/installer/cd-dvd/iso-image.nix
Arnout Engelen 88ee3b021d installer/cd-dvd/iso-image: avoid leaking build timestamps
When 'grafting' '/nix/store/<hash>-loopback.cfg' from disk onto
'/boot/grub/loopback.cfg' on the iso, the parent 'grub' directory does not
exist yet. In this case it is automatically created and inherits its
attributes, including timestamp, from /nix/store.

This is correct/expected/intentional behavior of xorriso, but has the
undesired result of leaking the timestamps of /nix/store into the iso. For
this reason we put the loopback.cfg in a
'/nix/store/<hash>-loopback.cfg/grub/loopback.cfg' instead, so it will inherit
the attributes from the correctly-timestamped
'/nix/store/<hash>-loopback.cfg/grub' directory.

For the same reason we move '/EFI/boot/efi-background.png' down in the list
so it is grafted after its parent '/EFI/boot' directory is created with
the correct timestamp.

fixes #74944
2019-12-11 09:07:40 +01:00

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# This module creates a bootable ISO image containing the given NixOS
# configuration. The derivation for the ISO image will be placed in
# config.system.build.isoImage.
{ config, lib, pkgs, ... }:
with lib;
let
/**
* Given a list of `options`, concats the result of mapping each options
* to a menuentry for use in grub.
*
* * defaults: {name, image, params, initrd}
* * options: [ option... ]
* * option: {name, params, class}
*/
menuBuilderGrub2 =
defaults: options: lib.concatStrings
(
map
(option: ''
menuentry '${defaults.name} ${
# Name appended to menuentry defaults to params if no specific name given.
option.name or (if option ? params then "(${option.params})" else "")
}' ${if option ? class then " --class ${option.class}" else ""} {
linux ${defaults.image} \''${isoboot} ${defaults.params} ${
option.params or ""
}
initrd ${defaults.initrd}
}
'')
options
)
;
/**
* Given a `config`, builds the default options.
*/
buildMenuGrub2 = config:
buildMenuAdditionalParamsGrub2 config ""
;
/**
* Given a `config` and params to add to `params`, build a set of default options.
* Use this one when creating a variant (e.g. hidpi)
*/
buildMenuAdditionalParamsGrub2 = config: additional:
let
finalCfg = {
name = "NixOS ${config.system.nixos.label}${config.isoImage.appendToMenuLabel}";
params = "init=${config.system.build.toplevel}/init ${additional} ${toString config.boot.kernelParams}";
image = "/boot/${config.system.boot.loader.kernelFile}";
initrd = "/boot/initrd";
};
in
menuBuilderGrub2
finalCfg
[
{ class = "installer"; }
{ class = "nomodeset"; params = "nomodeset"; }
{ class = "copytoram"; params = "copytoram"; }
{ class = "debug"; params = "debug"; }
]
;
# Timeout in syslinux is in units of 1/10 of a second.
# 0 is used to disable timeouts.
syslinuxTimeout = if config.boot.loader.timeout == null then
0
else
max (config.boot.loader.timeout * 10) 1;
max = x: y: if x > y then x else y;
# The configuration file for syslinux.
# Notes on syslinux configuration and UNetbootin compatiblity:
# * Do not use '/syslinux/syslinux.cfg' as the path for this
# configuration. UNetbootin will not parse the file and use it as-is.
# This results in a broken configuration if the partition label does
# not match the specified config.isoImage.volumeID. For this reason
# we're using '/isolinux/isolinux.cfg'.
# * Use APPEND instead of adding command-line arguments directly after
# the LINUX entries.
# * COM32 entries (chainload, reboot, poweroff) are not recognized. They
# result in incorrect boot entries.
baseIsolinuxCfg = ''
SERIAL 0 115200
TIMEOUT ${builtins.toString syslinuxTimeout}
UI vesamenu.c32
MENU TITLE NixOS
MENU BACKGROUND /isolinux/background.png
MENU RESOLUTION 800 600
MENU CLEAR
MENU ROWS 6
MENU CMDLINEROW -4
MENU TIMEOUTROW -3
MENU TABMSGROW -2
MENU HELPMSGROW -1
MENU HELPMSGENDROW -1
MENU MARGIN 0
# FG:AARRGGBB BG:AARRGGBB shadow
MENU COLOR BORDER 30;44 #00000000 #00000000 none
MENU COLOR SCREEN 37;40 #FF000000 #00E2E8FF none
MENU COLOR TABMSG 31;40 #80000000 #00000000 none
MENU COLOR TIMEOUT 1;37;40 #FF000000 #00000000 none
MENU COLOR TIMEOUT_MSG 37;40 #FF000000 #00000000 none
MENU COLOR CMDMARK 1;36;40 #FF000000 #00000000 none
MENU COLOR CMDLINE 37;40 #FF000000 #00000000 none
MENU COLOR TITLE 1;36;44 #00000000 #00000000 none
MENU COLOR UNSEL 37;44 #FF000000 #00000000 none
MENU COLOR SEL 7;37;40 #FFFFFFFF #FF5277C3 std
DEFAULT boot
LABEL boot
MENU LABEL NixOS ${config.system.nixos.label}${config.isoImage.appendToMenuLabel}
LINUX /boot/${config.system.boot.loader.kernelFile}
APPEND init=${config.system.build.toplevel}/init ${toString config.boot.kernelParams}
INITRD /boot/${config.system.boot.loader.initrdFile}
# A variant to boot with 'nomodeset'
LABEL boot-nomodeset
MENU LABEL NixOS ${config.system.nixos.label}${config.isoImage.appendToMenuLabel} (nomodeset)
LINUX /boot/${config.system.boot.loader.kernelFile}
APPEND init=${config.system.build.toplevel}/init ${toString config.boot.kernelParams} nomodeset
INITRD /boot/${config.system.boot.loader.initrdFile}
# A variant to boot with 'copytoram'
LABEL boot-copytoram
MENU LABEL NixOS ${config.system.nixos.label}${config.isoImage.appendToMenuLabel} (copytoram)
LINUX /boot/${config.system.boot.loader.kernelFile}
APPEND init=${config.system.build.toplevel}/init ${toString config.boot.kernelParams} copytoram
INITRD /boot/${config.system.boot.loader.initrdFile}
# A variant to boot with verbose logging to the console
LABEL boot-debug
MENU LABEL NixOS ${config.system.nixos.label}${config.isoImage.appendToMenuLabel} (debug)
LINUX /boot/${config.system.boot.loader.kernelFile}
APPEND init=${config.system.build.toplevel}/init ${toString config.boot.kernelParams} loglevel=7
INITRD /boot/${config.system.boot.loader.initrdFile}
'';
isolinuxMemtest86Entry = ''
LABEL memtest
MENU LABEL Memtest86+
LINUX /boot/memtest.bin
APPEND ${toString config.boot.loader.grub.memtest86.params}
'';
isolinuxCfg = concatStringsSep "\n"
([ baseIsolinuxCfg ] ++ optional config.boot.loader.grub.memtest86.enable isolinuxMemtest86Entry);
# Setup instructions for rEFInd.
refind =
if targetArch == "x64" then
''
# Adds rEFInd to the ISO.
cp -v ${pkgs.refind}/share/refind/refind_x64.efi $out/EFI/boot/
''
else
"# No refind for ${targetArch}"
;
grubPkgs = if config.boot.loader.grub.forcei686 then pkgs.pkgsi686Linux else pkgs;
grubMenuCfg = ''
#
# Menu configuration
#
insmod gfxterm
insmod png
set gfxpayload=keep
# Fonts can be loaded?
# (This font is assumed to always be provided as a fallback by NixOS)
if loadfont (hd0)/EFI/boot/unicode.pf2; then
# Use graphical term, it can be either with background image or a theme.
# input is "console", while output is "gfxterm".
# This enables "serial" input and output only when possible.
# Otherwise the failure mode is to not even enable gfxterm.
if test "\$with_serial" == "yes"; then
terminal_output gfxterm serial
terminal_input console serial
else
terminal_output gfxterm
terminal_input console
fi
else
# Sets colors for the non-graphical term.
set menu_color_normal=cyan/blue
set menu_color_highlight=white/blue
fi
${ # When there is a theme configured, use it, otherwise use the background image.
if config.isoImage.grubTheme != null then ''
# Sets theme.
set theme=(hd0)/EFI/boot/grub-theme/theme.txt
# Load theme fonts
$(find ${config.isoImage.grubTheme} -iname '*.pf2' -printf "loadfont (hd0)/EFI/boot/grub-theme/%P\n")
'' else ''
if background_image (hd0)/EFI/boot/efi-background.png; then
# Black background means transparent background when there
# is a background image set... This seems undocumented :(
set color_normal=black/black
set color_highlight=white/blue
else
# Falls back again to proper colors.
set menu_color_normal=cyan/blue
set menu_color_highlight=white/blue
fi
''}
'';
# The EFI boot image.
# Notes about grub:
# * Yes, the grubMenuCfg has to be repeated in all submenus. Otherwise you
# will get white-on-black console-like text on sub-menus. *sigh*
efiDir = pkgs.runCommand "efi-directory" {} ''
mkdir -p $out/EFI/boot/
# ALWAYS required modules.
MODULES="fat iso9660 part_gpt part_msdos \
normal boot linux configfile loopback chain halt \
efifwsetup efi_gop \
ls search search_label search_fs_uuid search_fs_file \
gfxmenu gfxterm gfxterm_background gfxterm_menu test all_video loadenv \
exfat ext2 ntfs btrfs hfsplus udf \
videoinfo png \
echo serial \
"
echo "Building GRUB with modules:"
for mod in $MODULES; do
echo " - $mod"
done
# Modules that may or may not be available per-platform.
echo "Adding additional modules:"
for mod in efi_uga; do
if [ -f ${grubPkgs.grub2_efi}/lib/grub/${grubPkgs.grub2_efi.grubTarget}/$mod.mod ]; then
echo " - $mod"
MODULES+=" $mod"
fi
done
# Make our own efi program, we can't rely on "grub-install" since it seems to
# probe for devices, even with --skip-fs-probe.
${grubPkgs.grub2_efi}/bin/grub-mkimage -o $out/EFI/boot/boot${targetArch}.efi -p /EFI/boot -O ${grubPkgs.grub2_efi.grubTarget} \
$MODULES
cp ${grubPkgs.grub2_efi}/share/grub/unicode.pf2 $out/EFI/boot/
cat <<EOF > $out/EFI/boot/grub.cfg
# If you want to use serial for "terminal_*" commands, you need to set one up:
# Example manual configuration:
# serial --unit=0 --speed=115200 --word=8 --parity=no --stop=1
# This uses the defaults, and makes the serial terminal available.
set with_serial=no
if serial; then set with_serial=yes ;fi
export with_serial
clear
set timeout=10
${grubMenuCfg}
# If the parameter iso_path is set, append the findiso parameter to the kernel
# line. We need this to allow the nixos iso to be booted from grub directly.
if [ \''${iso_path} ] ; then
set isoboot="findiso=\''${iso_path}"
fi
#
# Menu entries
#
${buildMenuGrub2 config}
submenu "HiDPI, Quirks and Accessibility" --class hidpi --class submenu {
${grubMenuCfg}
submenu "Suggests resolution @720p" --class hidpi-720p {
${grubMenuCfg}
${buildMenuAdditionalParamsGrub2 config "video=1280x720@60"}
}
submenu "Suggests resolution @1080p" --class hidpi-1080p {
${grubMenuCfg}
${buildMenuAdditionalParamsGrub2 config "video=1920x1080@60"}
}
# If we boot into a graphical environment where X is autoran
# and always crashes, it makes the media unusable. Allow the user
# to disable this.
submenu "Disable display-manager" --class quirk-disable-displaymanager {
${grubMenuCfg}
${buildMenuAdditionalParamsGrub2 config "systemd.mask=display-manager.service"}
}
# Some laptop and convertibles have the panel installed in an
# inconvenient way, rotated away from the keyboard.
# Those entries makes it easier to use the installer.
submenu "" {return}
submenu "Rotate framebuffer Clockwise" --class rotate-90cw {
${grubMenuCfg}
${buildMenuAdditionalParamsGrub2 config "fbcon=rotate:1"}
}
submenu "Rotate framebuffer Upside-Down" --class rotate-180 {
${grubMenuCfg}
${buildMenuAdditionalParamsGrub2 config "fbcon=rotate:2"}
}
submenu "Rotate framebuffer Counter-Clockwise" --class rotate-90ccw {
${grubMenuCfg}
${buildMenuAdditionalParamsGrub2 config "fbcon=rotate:3"}
}
# As a proof of concept, mainly. (Not sure it has accessibility merits.)
submenu "" {return}
submenu "Use black on white" --class accessibility-blakconwhite {
${grubMenuCfg}
${buildMenuAdditionalParamsGrub2 config "vt.default_red=0xFF,0xBC,0x4F,0xB4,0x56,0xBC,0x4F,0x00,0xA1,0xCF,0x84,0xCA,0x8D,0xB4,0x84,0x68 vt.default_grn=0xFF,0x55,0xBA,0xBA,0x4D,0x4D,0xB3,0x00,0xA0,0x8F,0xB3,0xCA,0x88,0x93,0xA4,0x68 vt.default_blu=0xFF,0x58,0x5F,0x58,0xC5,0xBD,0xC5,0x00,0xA8,0xBB,0xAB,0x97,0xBD,0xC7,0xC5,0x68"}
}
# Serial access is a must!
submenu "" {return}
submenu "Serial console=ttyS0,115200n8" --class serial {
${grubMenuCfg}
${buildMenuAdditionalParamsGrub2 config "console=ttyS0,115200n8"}
}
}
menuentry 'rEFInd' --class refind {
# UUID is hard-coded in the derivation.
search --set=root --no-floppy --fs-uuid 1234-5678
chainloader (\$root)/EFI/boot/refind_x64.efi
}
menuentry 'Firmware Setup' --class settings {
fwsetup
clear
echo ""
echo "If you see this message, your EFI system doesn't support this feature."
echo ""
}
menuentry 'Shutdown' --class shutdown {
halt
}
EOF
${refind}
'';
efiImg = pkgs.runCommand "efi-image_eltorito" { buildInputs = [ pkgs.mtools pkgs.libfaketime ]; }
# Be careful about determinism: du --apparent-size,
# dates (cp -p, touch, mcopy -m, faketime for label), IDs (mkfs.vfat -i)
''
mkdir ./contents && cd ./contents
cp -rp "${efiDir}"/EFI .
mkdir ./boot
cp -p "${config.boot.kernelPackages.kernel}/${config.system.boot.loader.kernelFile}" \
"${config.system.build.initialRamdisk}/${config.system.boot.loader.initrdFile}" ./boot/
touch --date=@0 ./EFI ./boot
usage_size=$(du -sb --apparent-size . | tr -cd '[:digit:]')
# Make the image 110% as big as the files need to make up for FAT overhead
image_size=$(( ($usage_size * 110) / 100 ))
# Make the image fit blocks of 1M
block_size=$((1024*1024))
image_size=$(( ($image_size / $block_size + 1) * $block_size ))
echo "Usage size: $usage_size"
echo "Image size: $image_size"
truncate --size=$image_size "$out"
${pkgs.libfaketime}/bin/faketime "2000-01-01 00:00:00" ${pkgs.dosfstools}/sbin/mkfs.vfat -i 12345678 -n EFIBOOT "$out"
mcopy -psvm -i "$out" ./EFI ./boot ::
# Verify the FAT partition.
${pkgs.dosfstools}/sbin/fsck.vfat -vn "$out"
''; # */
# Name used by UEFI for architectures.
targetArch =
if pkgs.stdenv.isi686 || config.boot.loader.grub.forcei686 then
"ia32"
else if pkgs.stdenv.isx86_64 then
"x64"
else if pkgs.stdenv.isAarch64 then
"aa64"
else
throw "Unsupported architecture";
# Syslinux (and isolinux) only supports x86-based architectures.
canx86BiosBoot = pkgs.stdenv.isi686 || pkgs.stdenv.isx86_64;
in
{
options = {
isoImage.isoName = mkOption {
default = "${config.isoImage.isoBaseName}.iso";
description = ''
Name of the generated ISO image file.
'';
};
isoImage.isoBaseName = mkOption {
default = "nixos";
description = ''
Prefix of the name of the generated ISO image file.
'';
};
isoImage.compressImage = mkOption {
default = false;
description = ''
Whether the ISO image should be compressed using
<command>bzip2</command>.
'';
};
isoImage.volumeID = mkOption {
default = "NIXOS_BOOT_CD";
description = ''
Specifies the label or volume ID of the generated ISO image.
Note that the label is used by stage 1 of the boot process to
mount the CD, so it should be reasonably distinctive.
'';
};
isoImage.contents = mkOption {
example = literalExample ''
[ { source = pkgs.memtest86 + "/memtest.bin";
target = "boot/memtest.bin";
}
]
'';
description = ''
This option lists files to be copied to fixed locations in the
generated ISO image.
'';
};
isoImage.storeContents = mkOption {
example = literalExample "[ pkgs.stdenv ]";
description = ''
This option lists additional derivations to be included in the
Nix store in the generated ISO image.
'';
};
isoImage.includeSystemBuildDependencies = mkOption {
default = false;
description = ''
Set this option to include all the needed sources etc in the
image. It significantly increases image size. Use that when
you want to be able to keep all the sources needed to build your
system or when you are going to install the system on a computer
with slow or non-existent network connection.
'';
};
isoImage.makeEfiBootable = mkOption {
default = false;
description = ''
Whether the ISO image should be an efi-bootable volume.
'';
};
isoImage.makeUsbBootable = mkOption {
default = false;
description = ''
Whether the ISO image should be bootable from CD as well as USB.
'';
};
isoImage.efiSplashImage = mkOption {
default = pkgs.fetchurl {
url = https://raw.githubusercontent.com/NixOS/nixos-artwork/a9e05d7deb38a8e005a2b52575a3f59a63a4dba0/bootloader/efi-background.png;
sha256 = "18lfwmp8yq923322nlb9gxrh5qikj1wsk6g5qvdh31c4h5b1538x";
};
description = ''
The splash image to use in the EFI bootloader.
'';
};
isoImage.splashImage = mkOption {
default = pkgs.fetchurl {
url = https://raw.githubusercontent.com/NixOS/nixos-artwork/a9e05d7deb38a8e005a2b52575a3f59a63a4dba0/bootloader/isolinux/bios-boot.png;
sha256 = "1wp822zrhbg4fgfbwkr7cbkr4labx477209agzc0hr6k62fr6rxd";
};
description = ''
The splash image to use in the legacy-boot bootloader.
'';
};
isoImage.grubTheme = mkOption {
default = pkgs.nixos-grub2-theme;
type = types.nullOr (types.either types.path types.package);
description = ''
The grub2 theme used for UEFI boot.
'';
};
isoImage.appendToMenuLabel = mkOption {
default = " Installer";
example = " Live System";
description = ''
The string to append after the menu label for the NixOS system.
This will be directly appended (without whitespace) to the NixOS version
string, like for example if it is set to <literal>XXX</literal>:
<para><literal>NixOS 99.99-pre666XXX</literal></para>
'';
};
};
config = {
boot.loader.grub.version = 2;
# Don't build the GRUB menu builder script, since we don't need it
# here and it causes a cyclic dependency.
boot.loader.grub.enable = false;
environment.systemPackages = [ grubPkgs.grub2 grubPkgs.grub2_efi ]
++ optional canx86BiosBoot pkgs.syslinux
;
# In stage 1 of the boot, mount the CD as the root FS by label so
# that we don't need to know its device. We pass the label of the
# root filesystem on the kernel command line, rather than in
# `fileSystems' below. This allows CD-to-USB converters such as
# UNetbootin to rewrite the kernel command line to pass the label or
# UUID of the USB stick. It would be nicer to write
# `root=/dev/disk/by-label/...' here, but UNetbootin doesn't
# recognise that.
boot.kernelParams =
[ "root=LABEL=${config.isoImage.volumeID}"
"boot.shell_on_fail"
];
fileSystems."/" =
{ fsType = "tmpfs";
options = [ "mode=0755" ];
};
# Note that /dev/root is a symlink to the actual root device
# specified on the kernel command line, created in the stage 1
# init script.
fileSystems."/iso" =
{ device = "/dev/root";
neededForBoot = true;
noCheck = true;
};
# In stage 1, mount a tmpfs on top of /nix/store (the squashfs
# image) to make this a live CD.
fileSystems."/nix/.ro-store" =
{ fsType = "squashfs";
device = "/iso/nix-store.squashfs";
options = [ "loop" ];
neededForBoot = true;
};
fileSystems."/nix/.rw-store" =
{ fsType = "tmpfs";
options = [ "mode=0755" ];
neededForBoot = true;
};
fileSystems."/nix/store" =
{ fsType = "unionfs-fuse";
device = "unionfs";
options = [ "allow_other" "cow" "nonempty" "chroot=/mnt-root" "max_files=32768" "hide_meta_files" "dirs=/nix/.rw-store=rw:/nix/.ro-store=ro" ];
};
boot.initrd.availableKernelModules = [ "squashfs" "iso9660" "uas" ];
boot.initrd.kernelModules = [ "loop" ];
# Closures to be copied to the Nix store on the CD, namely the init
# script and the top-level system configuration directory.
isoImage.storeContents =
[ config.system.build.toplevel ] ++
optional config.isoImage.includeSystemBuildDependencies
config.system.build.toplevel.drvPath;
# Create the squashfs image that contains the Nix store.
system.build.squashfsStore = pkgs.callPackage ../../../lib/make-squashfs.nix {
storeContents = config.isoImage.storeContents;
};
# Individual files to be included on the CD, outside of the Nix
# store on the CD.
isoImage.contents =
[
{ source = config.boot.kernelPackages.kernel + "/" + config.system.boot.loader.kernelFile;
target = "/boot/" + config.system.boot.loader.kernelFile;
}
{ source = config.system.build.initialRamdisk + "/" + config.system.boot.loader.initrdFile;
target = "/boot/" + config.system.boot.loader.initrdFile;
}
{ source = config.system.build.squashfsStore;
target = "/nix-store.squashfs";
}
{ source = config.isoImage.splashImage;
target = "/isolinux/background.png";
}
{ source = pkgs.writeText "version" config.system.nixos.label;
target = "/version.txt";
}
] ++ optionals canx86BiosBoot [
{ source = pkgs.substituteAll {
name = "isolinux.cfg";
src = pkgs.writeText "isolinux.cfg-in" isolinuxCfg;
bootRoot = "/boot";
};
target = "/isolinux/isolinux.cfg";
}
{ source = "${pkgs.syslinux}/share/syslinux";
target = "/isolinux";
}
] ++ optionals config.isoImage.makeEfiBootable [
{ source = efiImg;
target = "/boot/efi.img";
}
{ source = "${efiDir}/EFI";
target = "/EFI";
}
{ source = (pkgs.writeTextDir "grub/loopback.cfg" "source /EFI/boot/grub.cfg") + "/grub";
target = "/boot/grub";
}
] ++ optionals (config.boot.loader.grub.memtest86.enable && canx86BiosBoot) [
{ source = "${pkgs.memtest86plus}/memtest.bin";
target = "/boot/memtest.bin";
}
] ++ optionals (config.isoImage.grubTheme != null) [
{ source = config.isoImage.grubTheme;
target = "/EFI/boot/grub-theme";
}
] ++ [
{ source = config.isoImage.efiSplashImage;
target = "/EFI/boot/efi-background.png";
}
];
boot.loader.timeout = 10;
# Create the ISO image.
system.build.isoImage = pkgs.callPackage ../../../lib/make-iso9660-image.nix ({
inherit (config.isoImage) isoName compressImage volumeID contents;
bootable = canx86BiosBoot;
bootImage = "/isolinux/isolinux.bin";
syslinux = if canx86BiosBoot then pkgs.syslinux else null;
} // optionalAttrs (config.isoImage.makeUsbBootable && canx86BiosBoot) {
usbBootable = true;
isohybridMbrImage = "${pkgs.syslinux}/share/syslinux/isohdpfx.bin";
} // optionalAttrs config.isoImage.makeEfiBootable {
efiBootable = true;
efiBootImage = "boot/efi.img";
});
boot.postBootCommands =
''
# After booting, register the contents of the Nix store on the
# CD in the Nix database in the tmpfs.
${config.nix.package.out}/bin/nix-store --load-db < /nix/store/nix-path-registration
# nixos-rebuild also requires a "system" profile and an
# /etc/NIXOS tag.
touch /etc/NIXOS
${config.nix.package.out}/bin/nix-env -p /nix/var/nix/profiles/system --set /run/current-system
'';
# Add vfat support to the initrd to enable people to copy the
# contents of the CD to a bootable USB stick.
boot.initrd.supportedFilesystems = [ "vfat" ];
};
}