nixpkgs/nixos/modules/installer/tools/nixos-install.sh
Daniel Peebles 79d8ccf4f0 Merge pull request #28777 from copumpkin/installer-chroot
nixos-install: re-enable --chroot option
2017-09-26 12:23:19 -07:00

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#! @shell@
# - make Nix store etc.
# - copy closure of Nix to target device
# - register validity
# - with a chroot to the target device:
# * nix-env -p /nix/var/nix/profiles/system -i <nix-expr for the configuration>
# * install the boot loader
# Ensure a consistent umask.
umask 0022
# Re-exec ourselves in a private mount namespace so that our bind
# mounts get cleaned up automatically.
if [ "$(id -u)" = 0 ]; then
if [ -z "$NIXOS_INSTALL_REEXEC" ]; then
export NIXOS_INSTALL_REEXEC=1
exec unshare --mount --uts -- "$0" "$@"
else
mount --make-rprivate /
fi
fi
# Parse the command line for the -I flag
extraBuildFlags=()
chrootCommand=(/run/current-system/sw/bin/bash)
buildUsersGroup="nixbld"
while [ "$#" -gt 0 ]; do
i="$1"; shift 1
case "$i" in
--max-jobs|-j|--cores|-I)
j="$1"; shift 1
extraBuildFlags+=("$i" "$j")
;;
--option)
j="$1"; shift 1
k="$1"; shift 1
extraBuildFlags+=("$i" "$j" "$k")
;;
--root)
mountPoint="$1"; shift 1
;;
--closure)
closure="$1"; shift 1
buildUsersGroup=""
;;
--no-channel-copy)
noChannelCopy=1
;;
--no-root-passwd)
noRootPasswd=1
;;
--no-bootloader)
noBootLoader=1
;;
--show-trace)
extraBuildFlags+=("$i")
;;
--chroot)
runChroot=1
if [[ "$@" != "" ]]; then
chrootCommand=("$@")
fi
break
;;
--help)
exec man nixos-install
exit 1
;;
*)
echo "$0: unknown option \`$i'"
exit 1
;;
esac
done
set -e
shopt -s nullglob
if test -z "$mountPoint"; then
mountPoint=/mnt
fi
if ! test -e "$mountPoint"; then
echo "mount point $mountPoint doesn't exist"
exit 1
fi
# Get the path of the NixOS configuration file.
if test -z "$NIXOS_CONFIG"; then
NIXOS_CONFIG=/etc/nixos/configuration.nix
fi
if [ ! -e "$mountPoint/$NIXOS_CONFIG" ] && [ -z "$closure" ]; then
echo "configuration file $mountPoint/$NIXOS_CONFIG doesn't exist"
exit 1
fi
# Builds will use users that are members of this group
extraBuildFlags+=(--option "build-users-group" "$buildUsersGroup")
# Inherit binary caches from the host
# TODO: will this still work with Nix 1.12 now that it has no perl? Probably not...
binary_caches="$(@perl@/bin/perl -I @nix@/lib/perl5/site_perl/*/* -e 'use Nix::Config; Nix::Config::readConfig; print $Nix::Config::config{"binary-caches"};')"
extraBuildFlags+=(--option "binary-caches" "$binary_caches")
# We only need nixpkgs in the path if we don't already have a system closure to install
if [[ -z "$closure" ]]; then
nixpkgs="$(readlink -f "$(nix-instantiate --find-file nixpkgs)")"
export NIX_PATH="nixpkgs=$nixpkgs:nixos-config=$mountPoint/$NIXOS_CONFIG"
fi
unset NIXOS_CONFIG
# These get created in nixos-prepare-root as well, but we want to make sure they're here in case we're
# running with --chroot. TODO: --chroot should just be split into a separate tool.
mkdir -m 0755 -p "$mountPoint/dev" "$mountPoint/proc" "$mountPoint/sys"
# Set up some bind mounts we'll want regardless of chroot or not
mount --rbind /dev "$mountPoint/dev"
mount --rbind /proc "$mountPoint/proc"
mount --rbind /sys "$mountPoint/sys"
# If we asked for a chroot, that means we're not actually installing anything (yeah I was confused too)
# and we just want to run a command in the context of a $mountPoint that we're assuming has already been
# set up by a previous nixos-install invocation. In that case we set up some remaining bind mounts and
# exec the requested command, skipping the rest of the installation procedure.
if [ -n "$runChroot" ]; then
mount -t tmpfs -o "mode=0755" none $mountPoint/run
rm -rf $mountPoint/var/run
ln -s /run $mountPoint/var/run
for f in /etc/resolv.conf /etc/hosts; do rm -f $mountPoint/$f; [ -f "$f" ] && cp -Lf $f $mountPoint/etc/; done
for f in /etc/passwd /etc/group; do touch $mountPoint/$f; [ -f "$f" ] && mount --rbind -o ro $f $mountPoint/$f; done
if ! [ -L $mountPoint/nix/var/nix/profiles/system ]; then
echo "$0: installation not finished; cannot chroot into installation directory"
exit 1
fi
ln -s /nix/var/nix/profiles/system $mountPoint/run/current-system
exec chroot $mountPoint "${chrootCommand[@]}"
fi
# A place to drop temporary closures
trap "rm -rf $tmpdir" EXIT
tmpdir="$(mktemp -d)"
# Build a closure (on the host; we then copy it into the guest)
function closure() {
nix-build "${extraBuildFlags[@]}" --no-out-link -E "with import <nixpkgs> {}; runCommand \"closure\" { exportReferencesGraph = [ \"x\" (buildEnv { name = \"env\"; paths = [ ($1) stdenv ]; }) ]; } \"cp x \$out\""
}
system_closure="$tmpdir/system.closure"
# Use a FIFO for piping nix-store --export into nix-store --import, saving disk
# I/O and space. nix-store --import is run by nixos-prepare-root.
mkfifo $system_closure
if [ -z "$closure" ]; then
expr="(import <nixpkgs/nixos> {}).system"
system_root="$(nix-build -E "$expr")"
system_closure="$(closure "$expr")"
else
system_root=$closure
# Create a temporary file ending in .closure (so nixos-prepare-root knows to --import it) to transport the store closure
# to the filesytem we're preparing. Also delete it on exit!
# Run in background to avoid blocking while trying to write to the FIFO
# $system_closure refers to
nix-store --export $(nix-store -qR $closure) > $system_closure &
fi
channel_root="$(nix-env -p /nix/var/nix/profiles/per-user/root/channels -q nixos --no-name --out-path 2>/dev/null || echo -n "")"
channel_closure="$tmpdir/channel.closure"
nix-store --export $channel_root > $channel_closure
# Populate the target root directory with the basics
@prepare_root@/bin/nixos-prepare-root "$mountPoint" "$channel_root" "$system_root" @nixClosure@ "$system_closure" "$channel_closure"
# nixos-prepare-root doesn't currently do anything with file ownership, so we set it up here instead
chown @root_uid@:@nixbld_gid@ $mountPoint/nix/store
# Grub needs an mtab.
ln -sfn /proc/mounts $mountPoint/etc/mtab
# Switch to the new system configuration. This will install Grub with
# a menu default pointing at the kernel/initrd/etc of the new
# configuration.
echo "finalising the installation..."
if [ -z "$noBootLoader" ]; then
NIXOS_INSTALL_BOOTLOADER=1 chroot $mountPoint \
/nix/var/nix/profiles/system/bin/switch-to-configuration boot
fi
# Run the activation script.
chroot $mountPoint /nix/var/nix/profiles/system/activate
# Ask the user to set a root password.
if [ -z "$noRootPasswd" ] && chroot $mountPoint [ -x /run/wrappers/bin/passwd ] && [ -t 0 ]; then
echo "setting root password..."
chroot $mountPoint /run/wrappers/bin/passwd
fi
echo "installation finished!"