mirror of
https://github.com/NixOS/nixpkgs.git
synced 2024-11-29 18:33:00 +00:00
477 lines
14 KiB
Perl
Executable File
477 lines
14 KiB
Perl
Executable File
#! @perl@
|
||
|
||
use strict;
|
||
use POSIX;
|
||
use File::Path;
|
||
use File::Slurp;
|
||
use Fcntl ':flock';
|
||
use Getopt::Long qw(:config gnu_getopt no_bundling);
|
||
use Cwd 'abs_path';
|
||
use Time::HiRes;
|
||
|
||
my $nsenter = "@utillinux@/bin/nsenter";
|
||
my $su = "@su@";
|
||
|
||
# Ensure a consistent umask.
|
||
umask 0022;
|
||
|
||
# Ensure $NIXOS_CONFIG is not set.
|
||
$ENV{"NIXOS_CONFIG"} = "";
|
||
|
||
# Parse the command line.
|
||
|
||
sub showHelp {
|
||
print <<EOF;
|
||
Usage: nixos-container list
|
||
nixos-container create <container-name>
|
||
[--nixos-path <path>]
|
||
[--system-path <path>]
|
||
[--config <string>]
|
||
[--config-file <path>]
|
||
[--flake <flakeref>]
|
||
[--ensure-unique-name]
|
||
[--auto-start]
|
||
[--bridge <iface>]
|
||
[--port <port>]
|
||
[--host-address <string>]
|
||
[--local-address <string>]
|
||
nixos-container destroy <container-name>
|
||
nixos-container start <container-name>
|
||
nixos-container stop <container-name>
|
||
nixos-container terminate <container-name>
|
||
nixos-container status <container-name>
|
||
nixos-container update <container-name>
|
||
[--config <string>]
|
||
[--config-file <path>]
|
||
[--flake <flakeref>]
|
||
[--nixos-path <path>]
|
||
nixos-container login <container-name>
|
||
nixos-container root-login <container-name>
|
||
nixos-container run <container-name> -- args...
|
||
nixos-container show-ip <container-name>
|
||
nixos-container show-host-key <container-name>
|
||
EOF
|
||
exit 0;
|
||
}
|
||
|
||
my $systemPath;
|
||
my $nixosPath;
|
||
my $ensureUniqueName = 0;
|
||
my $autoStart = 0;
|
||
my $bridge;
|
||
my $port;
|
||
my $extraConfig;
|
||
my $signal;
|
||
my $configFile;
|
||
my $hostAddress;
|
||
my $localAddress;
|
||
my $flake;
|
||
my $flakeAttr = "container";
|
||
|
||
# Nix passthru flags.
|
||
my @nixFlags;
|
||
my @nixFlags2;
|
||
|
||
sub copyNixFlags0 { push @nixFlags, "--$_[0]"; }
|
||
sub copyNixFlags1 { push @nixFlags, "--$_[0]", $_[1]; }
|
||
|
||
# Ugly hack to handle flags that take two arguments, like --option.
|
||
sub copyNixFlags2 {
|
||
if (scalar(@nixFlags2) % 3 == 0) {
|
||
push @nixFlags2, "--$_[0]", $_[1];
|
||
} else {
|
||
push @nixFlags2, $_[1];
|
||
}
|
||
}
|
||
|
||
GetOptions(
|
||
"help" => sub { showHelp() },
|
||
"ensure-unique-name" => \$ensureUniqueName,
|
||
"auto-start" => \$autoStart,
|
||
"bridge=s" => \$bridge,
|
||
"port=s" => \$port,
|
||
"system-path=s" => \$systemPath,
|
||
"signal=s" => \$signal,
|
||
"nixos-path=s" => \$nixosPath,
|
||
"config=s" => \$extraConfig,
|
||
"config-file=s" => \$configFile,
|
||
"host-address=s" => \$hostAddress,
|
||
"local-address=s" => \$localAddress,
|
||
"flake=s" => \$flake,
|
||
# Nix passthru options.
|
||
"log-format=s" => \©NixFlags1,
|
||
"option=s{2}" => \©NixFlags2,
|
||
"impure" => \©NixFlags0,
|
||
"update-input=s" => \©NixFlags1,
|
||
"override-input=s{2}" => \©NixFlags2,
|
||
"commit-lock-file" => \©NixFlags0,
|
||
"no-registries" => \©NixFlags0,
|
||
"no-update-lock-file" => \©NixFlags0,
|
||
"no-write-lock-file" => \©NixFlags0,
|
||
"no-allow-dirty" => \©NixFlags0,
|
||
"recreate-lock-file" => \©NixFlags0,
|
||
) or exit 1;
|
||
|
||
push @nixFlags, @nixFlags2;
|
||
|
||
if (defined $hostAddress and !defined $localAddress or defined $localAddress and !defined $hostAddress) {
|
||
die "With --host-address set, --local-address is required as well!";
|
||
}
|
||
|
||
my $action = $ARGV[0] or die "$0: no action specified\n";
|
||
|
||
if (defined $configFile and defined $extraConfig) {
|
||
die "--config and --config-file are mutually incompatible. " .
|
||
"Please define one or the other, but not both";
|
||
}
|
||
|
||
if (defined $flake && $flake =~ /^(.*)#([^#"]+)$/) {
|
||
$flake = $1;
|
||
$flakeAttr = $2;
|
||
}
|
||
|
||
# Execute the selected action.
|
||
|
||
mkpath("/etc/containers", 0, 0755);
|
||
mkpath("/var/lib/containers", 0, 0700);
|
||
|
||
if ($action eq "list") {
|
||
foreach my $confFile (glob "/etc/containers/*.conf") {
|
||
$confFile =~ /\/([^\/]+).conf$/ or next;
|
||
print "$1\n";
|
||
}
|
||
exit 0;
|
||
}
|
||
|
||
my $containerName = $ARGV[1] or die "$0: no container name specified\n";
|
||
$containerName =~ /^[a-zA-Z0-9_-]+$/ or die "$0: invalid container name\n";
|
||
|
||
sub writeNixOSConfig {
|
||
my ($nixosConfigFile) = @_;
|
||
|
||
my $localExtraConfig = "";
|
||
|
||
if ($extraConfig) {
|
||
$localExtraConfig = $extraConfig
|
||
} elsif ($configFile) {
|
||
my $resolvedFile = abs_path($configFile);
|
||
$localExtraConfig = "imports = [ $resolvedFile ];"
|
||
}
|
||
|
||
my $nixosConfig = <<EOF;
|
||
{ config, lib, pkgs, ... }:
|
||
|
||
with lib;
|
||
|
||
{ boot.isContainer = true;
|
||
networking.hostName = mkDefault "$containerName";
|
||
networking.useDHCP = false;
|
||
$localExtraConfig
|
||
}
|
||
EOF
|
||
|
||
write_file($nixosConfigFile, $nixosConfig);
|
||
}
|
||
|
||
sub buildFlake {
|
||
system("nix", "build", "-o", "$systemPath.tmp", @nixFlags, "--",
|
||
"$flake#nixosConfigurations.\"$flakeAttr\".config.system.build.toplevel") == 0
|
||
or die "$0: failed to build container from flake '$flake'\n";
|
||
$systemPath = readlink("$systemPath.tmp") or die;
|
||
unlink("$systemPath.tmp");
|
||
}
|
||
|
||
sub clearContainerState {
|
||
my ($profileDir, $gcRootsDir, $root, $configFile) = @_;
|
||
|
||
safeRemoveTree($profileDir) if -e $profileDir;
|
||
safeRemoveTree($gcRootsDir) if -e $gcRootsDir;
|
||
system("chattr", "-i", "$root/var/empty") if -e "$root/var/empty";
|
||
safeRemoveTree($root) if -e $root;
|
||
unlink($configFile) or die;
|
||
}
|
||
|
||
if ($action eq "create") {
|
||
# Acquire an exclusive lock to prevent races with other
|
||
# invocations of ‘nixos-container create’.
|
||
my $lockFN = "/run/lock/nixos-container";
|
||
open(my $lock, '>>', $lockFN) or die "$0: opening $lockFN: $!";
|
||
flock($lock, LOCK_EX) or die "$0: could not lock $lockFN: $!";
|
||
|
||
my $confFile = "/etc/containers/$containerName.conf";
|
||
my $root = "/var/lib/containers/$containerName";
|
||
|
||
# Maybe generate a unique name.
|
||
if ($ensureUniqueName) {
|
||
my $base = $containerName;
|
||
for (my $nr = 0; ; $nr++) {
|
||
$confFile = "/etc/containers/$containerName.conf";
|
||
$root = "/var/lib/containers/$containerName";
|
||
last unless -e $confFile || -e $root;
|
||
$containerName = "$base-$nr";
|
||
}
|
||
}
|
||
|
||
die "$0: container ‘$containerName’ already exists\n" if -e $confFile;
|
||
|
||
# Due to interface name length restrictions, container names must
|
||
# be restricted too.
|
||
die "$0: container name ‘$containerName’ is too long\n" if length $containerName > 11;
|
||
|
||
# Get an unused IP address.
|
||
my %usedIPs;
|
||
foreach my $confFile2 (glob "/etc/containers/*.conf") {
|
||
my $s = read_file($confFile2) or die;
|
||
$usedIPs{$1} = 1 if $s =~ /^HOST_ADDRESS=([0-9\.]+)$/m;
|
||
$usedIPs{$1} = 1 if $s =~ /^LOCAL_ADDRESS=([0-9\.]+)$/m;
|
||
}
|
||
|
||
unless (defined $hostAddress) {
|
||
my $ipPrefix;
|
||
for (my $nr = 1; $nr < 255; $nr++) {
|
||
$ipPrefix = "10.233.$nr";
|
||
$hostAddress = "$ipPrefix.1";
|
||
$localAddress = "$ipPrefix.2";
|
||
last unless $usedIPs{$hostAddress} || $usedIPs{$localAddress};
|
||
$ipPrefix = undef;
|
||
}
|
||
|
||
die "$0: out of IP addresses\n" unless defined $ipPrefix;
|
||
}
|
||
|
||
my @conf;
|
||
push @conf, "PRIVATE_NETWORK=1\n";
|
||
push @conf, "HOST_ADDRESS=$hostAddress\n";
|
||
push @conf, "LOCAL_ADDRESS=$localAddress\n";
|
||
push @conf, "HOST_BRIDGE=$bridge\n";
|
||
push @conf, "HOST_PORT=$port\n";
|
||
push @conf, "AUTO_START=$autoStart\n";
|
||
push @conf, "FLAKE=$flake\n" if defined $flake;
|
||
write_file($confFile, \@conf);
|
||
|
||
close($lock);
|
||
|
||
print STDERR "host IP is $hostAddress, container IP is $localAddress\n";
|
||
|
||
# The per-container directory is restricted to prevent users on
|
||
# the host from messing with guest users who happen to have the
|
||
# same uid.
|
||
my $profileDir = "/nix/var/nix/profiles/per-container";
|
||
mkpath($profileDir, 0, 0700);
|
||
$profileDir = "$profileDir/$containerName";
|
||
mkpath($profileDir, 0, 0755);
|
||
|
||
# Build/set the initial configuration.
|
||
if (defined $flake) {
|
||
buildFlake();
|
||
}
|
||
|
||
if (defined $systemPath) {
|
||
system("nix-env", "-p", "$profileDir/system", "--set", $systemPath) == 0
|
||
or do {
|
||
clearContainerState($profileDir, "$profileDir/$containerName", $root, $confFile);
|
||
die "$0: failed to set initial container configuration\n";
|
||
};
|
||
} else {
|
||
mkpath("$root/etc/nixos", 0, 0755);
|
||
|
||
my $nixenvF = $nixosPath // "<nixpkgs/nixos>";
|
||
my $nixosConfigFile = "$root/etc/nixos/configuration.nix";
|
||
writeNixOSConfig $nixosConfigFile;
|
||
|
||
system("nix-env", "-p", "$profileDir/system",
|
||
"-I", "nixos-config=$nixosConfigFile", "-f", "$nixenvF",
|
||
"--set", "-A", "system", @nixFlags) == 0
|
||
or do {
|
||
clearContainerState($profileDir, "$profileDir/$containerName", $root, $confFile);
|
||
die "$0: failed to build initial container configuration\n"
|
||
};
|
||
}
|
||
|
||
print "$containerName\n" if $ensureUniqueName;
|
||
exit 0;
|
||
}
|
||
|
||
my $root = "/var/lib/containers/$containerName";
|
||
my $profileDir = "/nix/var/nix/profiles/per-container/$containerName";
|
||
my $gcRootsDir = "/nix/var/nix/gcroots/per-container/$containerName";
|
||
my $confFile = "/etc/containers/$containerName.conf";
|
||
if (!-e $confFile) {
|
||
if ($action eq "destroy") {
|
||
exit 0;
|
||
} elsif ($action eq "status") {
|
||
print "gone\n";
|
||
}
|
||
die "$0: container ‘$containerName’ does not exist\n" ;
|
||
}
|
||
|
||
# Return the PID of the init process of the container.
|
||
sub getLeader {
|
||
my $s = `machinectl show "$containerName" -p Leader`;
|
||
chomp $s;
|
||
$s =~ /^Leader=(\d+)$/ or die "unable to get container's main PID\n";
|
||
return int($1);
|
||
}
|
||
|
||
sub isContainerRunning {
|
||
my $status = `systemctl show 'container\@$containerName'`;
|
||
return $status =~ /ActiveState=active/;
|
||
}
|
||
|
||
sub terminateContainer {
|
||
my $leader = getLeader;
|
||
system("machinectl", "terminate", $containerName) == 0
|
||
or die "$0: failed to terminate container\n";
|
||
# Wait for the leader process to exit
|
||
# TODO: As for any use of PIDs for process control where the process is
|
||
# not a direct child of ours, this can go wrong when the pid gets
|
||
# recycled after a PID overflow.
|
||
# Relying entirely on some form of UUID provided by machinectl
|
||
# instead of PIDs would remove this risk.
|
||
# See https://github.com/NixOS/nixpkgs/pull/32992#discussion_r158586048
|
||
while ( kill 0, $leader ) { Time::HiRes::sleep(0.1) }
|
||
}
|
||
|
||
sub startContainer {
|
||
system("systemctl", "start", "container\@$containerName") == 0
|
||
or die "$0: failed to start container\n";
|
||
}
|
||
|
||
sub stopContainer {
|
||
system("systemctl", "stop", "container\@$containerName") == 0
|
||
or die "$0: failed to stop container\n";
|
||
}
|
||
|
||
sub restartContainer {
|
||
stopContainer;
|
||
startContainer;
|
||
}
|
||
|
||
# Run a command in the container.
|
||
sub runInContainer {
|
||
my @args = @_;
|
||
my $leader = getLeader;
|
||
exec($nsenter, "-t", $leader, "-m", "-u", "-i", "-n", "-p", "--", @args);
|
||
die "cannot run ‘nsenter’: $!\n";
|
||
}
|
||
|
||
# Remove a directory while recursively unmounting all mounted filesystems within
|
||
# that directory and unmounting/removing that directory afterwards as well.
|
||
#
|
||
# NOTE: If the specified path is a mountpoint, its contents will be removed,
|
||
# only mountpoints underneath that path will be unmounted properly.
|
||
sub safeRemoveTree {
|
||
my ($path) = @_;
|
||
system("find", $path, "-mindepth", "1", "-xdev",
|
||
"(", "-type", "d", "-exec", "mountpoint", "-q", "{}", ";", ")",
|
||
"-exec", "umount", "-fR", "{}", "+");
|
||
system("rm", "--one-file-system", "-rf", $path);
|
||
if (-e $path) {
|
||
system("umount", "-fR", $path);
|
||
system("rm", "--one-file-system", "-rf", $path);
|
||
}
|
||
}
|
||
|
||
if ($action eq "destroy") {
|
||
die "$0: cannot destroy declarative container (remove it from your configuration.nix instead)\n"
|
||
unless POSIX::access($confFile, &POSIX::W_OK);
|
||
|
||
terminateContainer if (isContainerRunning);
|
||
|
||
clearContainerState($profileDir, $gcRootsDir, $root, $confFile);
|
||
}
|
||
|
||
elsif ($action eq "restart") {
|
||
restartContainer;
|
||
}
|
||
|
||
elsif ($action eq "start") {
|
||
startContainer;
|
||
}
|
||
|
||
elsif ($action eq "stop") {
|
||
stopContainer;
|
||
}
|
||
|
||
elsif ($action eq "terminate") {
|
||
terminateContainer;
|
||
}
|
||
|
||
elsif ($action eq "status") {
|
||
print isContainerRunning() ? "up" : "down", "\n";
|
||
}
|
||
|
||
elsif ($action eq "update") {
|
||
|
||
# Unless overriden on the command line, rebuild the flake recorded
|
||
# in the container config file. FIXME: read the container config
|
||
# in a more sensible way.
|
||
if (!defined $flake && !defined $configFile && !defined $extraConfig) {
|
||
my $s = read_file($confFile);
|
||
$s =~ /^FLAKE=(.*)$/m;
|
||
$flake = $1;
|
||
}
|
||
|
||
if (defined $flake) {
|
||
buildFlake();
|
||
system("nix-env", "-p", "$profileDir/system", "--set", $systemPath) == 0
|
||
or die "$0: failed to set container configuration\n";
|
||
} else {
|
||
|
||
my $nixosConfigFile = "$root/etc/nixos/configuration.nix";
|
||
|
||
# FIXME: may want to be more careful about clobbering the existing
|
||
# configuration.nix.
|
||
if ((defined $extraConfig && $extraConfig ne "") ||
|
||
(defined $configFile && $configFile ne "")) {
|
||
writeNixOSConfig $nixosConfigFile;
|
||
}
|
||
|
||
my $nixenvF = $nixosPath // "<nixpkgs/nixos>";
|
||
system("nix-env", "-p", "$profileDir/system",
|
||
"-I", "nixos-config=$nixosConfigFile", "-f", $nixenvF,
|
||
"--set", "-A", "system", @nixFlags) == 0
|
||
or die "$0: failed to build container configuration\n";
|
||
}
|
||
|
||
if (isContainerRunning) {
|
||
print STDERR "reloading container...\n";
|
||
system("systemctl", "reload", "container\@$containerName") == 0
|
||
or die "$0: failed to reload container\n";
|
||
}
|
||
}
|
||
|
||
elsif ($action eq "login") {
|
||
exec("machinectl", "login", "--", $containerName);
|
||
}
|
||
|
||
elsif ($action eq "root-login") {
|
||
runInContainer("@su@", "root", "-l");
|
||
}
|
||
|
||
elsif ($action eq "run") {
|
||
shift @ARGV; shift @ARGV;
|
||
# Escape command.
|
||
my $s = join(' ', map { s/'/'\\''/g; "'$_'" } @ARGV);
|
||
runInContainer("@su@", "root", "-l", "-c", "exec " . $s);
|
||
}
|
||
|
||
elsif ($action eq "show-ip") {
|
||
my $s = read_file($confFile) or die;
|
||
$s =~ /^LOCAL_ADDRESS=([0-9\.]+)(\/[0-9]+)?$/m
|
||
or $s =~ /^LOCAL_ADDRESS6=([0-9a-f:]+)(\/[0-9]+)?$/m
|
||
or die "$0: cannot get IP address\n";
|
||
print "$1\n";
|
||
}
|
||
|
||
elsif ($action eq "show-host-key") {
|
||
my $fn = "$root/etc/ssh/ssh_host_ed25519_key.pub";
|
||
$fn = "$root/etc/ssh/ssh_host_ecdsa_key.pub" unless -e $fn;
|
||
exit 1 if ! -f $fn;
|
||
print read_file($fn);
|
||
}
|
||
|
||
else {
|
||
die "$0: unknown action ‘$action’\n";
|
||
}
|