diff options
Diffstat (limited to 'nixpkgs/nixos/modules/system/boot/loader/systemd-boot/systemd-boot-builder.py')
| -rw-r--r-- | nixpkgs/nixos/modules/system/boot/loader/systemd-boot/systemd-boot-builder.py | 240 |
1 files changed, 240 insertions, 0 deletions
diff --git a/nixpkgs/nixos/modules/system/boot/loader/systemd-boot/systemd-boot-builder.py b/nixpkgs/nixos/modules/system/boot/loader/systemd-boot/systemd-boot-builder.py new file mode 100644 index 00000000000..f48a085ce57 --- /dev/null +++ b/nixpkgs/nixos/modules/system/boot/loader/systemd-boot/systemd-boot-builder.py @@ -0,0 +1,240 @@ +#! @python3@/bin/python3 -B +import argparse +import shutil +import os +import sys +import errno +import subprocess +import glob +import tempfile +import errno +import warnings +import ctypes +libc = ctypes.CDLL("libc.so.6") +import re +import datetime +import glob +import os.path + +def copy_if_not_exists(source, dest): + if not os.path.exists(dest): + shutil.copyfile(source, dest) + +def system_dir(profile, generation): + if profile: + return "/nix/var/nix/profiles/system-profiles/%s-%d-link" % (profile, generation) + else: + return "/nix/var/nix/profiles/system-%d-link" % (generation) + +BOOT_ENTRY = """title NixOS{profile} +version Generation {generation} {description} +linux {kernel} +initrd {initrd} +options {kernel_params} +""" + +# The boot loader entry for memtest86. +# +# TODO: This is hard-coded to use the 64-bit EFI app, but it could probably +# be updated to use the 32-bit EFI app on 32-bit systems. The 32-bit EFI +# app filename is BOOTIA32.efi. +MEMTEST_BOOT_ENTRY = """title MemTest86 +efi /efi/memtest86/BOOTX64.efi +""" + +def write_loader_conf(profile, generation): + with open("@efiSysMountPoint@/loader/loader.conf.tmp", 'w') as f: + if "@timeout@" != "": + f.write("timeout @timeout@\n") + if profile: + f.write("default nixos-%s-generation-%d\n" % (profile, generation)) + else: + f.write("default nixos-generation-%d\n" % (generation)) + if not @editor@: + f.write("editor 0\n"); + f.write("console-mode @consoleMode@\n"); + os.rename("@efiSysMountPoint@/loader/loader.conf.tmp", "@efiSysMountPoint@/loader/loader.conf") + +def profile_path(profile, generation, name): + return os.readlink("%s/%s" % (system_dir(profile, generation), name)) + +def copy_from_profile(profile, generation, name, dry_run=False): + store_file_path = profile_path(profile, generation, name) + suffix = os.path.basename(store_file_path) + store_dir = os.path.basename(os.path.dirname(store_file_path)) + efi_file_path = "/efi/nixos/%s-%s.efi" % (store_dir, suffix) + if not dry_run: + copy_if_not_exists(store_file_path, "@efiSysMountPoint@%s" % (efi_file_path)) + return efi_file_path + +def describe_generation(generation_dir): + try: + with open("%s/nixos-version" % generation_dir) as f: + nixos_version = f.read() + except IOError: + nixos_version = "Unknown" + + kernel_dir = os.path.dirname(os.path.realpath("%s/kernel" % generation_dir)) + module_dir = glob.glob("%s/lib/modules/*" % kernel_dir)[0] + kernel_version = os.path.basename(module_dir) + + build_time = int(os.path.getctime(generation_dir)) + build_date = datetime.datetime.fromtimestamp(build_time).strftime('%F') + + description = "NixOS {}, Linux Kernel {}, Built on {}".format( + nixos_version, kernel_version, build_date + ) + + return description + +def write_entry(profile, generation, machine_id): + kernel = copy_from_profile(profile, generation, "kernel") + initrd = copy_from_profile(profile, generation, "initrd") + try: + append_initrd_secrets = profile_path(profile, generation, "append-initrd-secrets") + subprocess.check_call([append_initrd_secrets, "@efiSysMountPoint@%s" % (initrd)]) + except FileNotFoundError: + pass + if profile: + entry_file = "@efiSysMountPoint@/loader/entries/nixos-%s-generation-%d.conf" % (profile, generation) + else: + entry_file = "@efiSysMountPoint@/loader/entries/nixos-generation-%d.conf" % (generation) + generation_dir = os.readlink(system_dir(profile, generation)) + tmp_path = "%s.tmp" % (entry_file) + kernel_params = "systemConfig=%s init=%s/init " % (generation_dir, generation_dir) + + with open("%s/kernel-params" % (generation_dir)) as params_file: + kernel_params = kernel_params + params_file.read() + with open(tmp_path, 'w') as f: + f.write(BOOT_ENTRY.format(profile=" [" + profile + "]" if profile else "", + generation=generation, + kernel=kernel, + initrd=initrd, + kernel_params=kernel_params, + description=describe_generation(generation_dir))) + if machine_id is not None: + f.write("machine-id %s\n" % machine_id) + os.rename(tmp_path, entry_file) + +def mkdir_p(path): + try: + os.makedirs(path) + except OSError as e: + if e.errno != errno.EEXIST or not os.path.isdir(path): + raise + +def get_generations(profile=None): + gen_list = subprocess.check_output([ + "@nix@/bin/nix-env", + "--list-generations", + "-p", + "/nix/var/nix/profiles/%s" % ("system-profiles/" + profile if profile else "system"), + "--option", "build-users-group", ""], + universal_newlines=True) + gen_lines = gen_list.split('\n') + gen_lines.pop() + + configurationLimit = @configurationLimit@ + return [ (profile, int(line.split()[0])) for line in gen_lines ][-configurationLimit:] + +def remove_old_entries(gens): + rex_profile = re.compile("^@efiSysMountPoint@/loader/entries/nixos-(.*)-generation-.*\.conf$") + rex_generation = re.compile("^@efiSysMountPoint@/loader/entries/nixos.*-generation-(.*)\.conf$") + known_paths = [] + for gen in gens: + known_paths.append(copy_from_profile(*gen, "kernel", True)) + known_paths.append(copy_from_profile(*gen, "initrd", True)) + for path in glob.iglob("@efiSysMountPoint@/loader/entries/nixos*-generation-[1-9]*.conf"): + try: + if rex_profile.match(path): + prof = rex_profile.sub(r"\1", path) + else: + prof = "system" + gen = int(rex_generation.sub(r"\1", path)) + if not (prof, gen) in gens: + os.unlink(path) + except ValueError: + pass + for path in glob.iglob("@efiSysMountPoint@/efi/nixos/*"): + if not path in known_paths and not os.path.isdir(path): + os.unlink(path) + +def get_profiles(): + if os.path.isdir("/nix/var/nix/profiles/system-profiles/"): + return [x + for x in os.listdir("/nix/var/nix/profiles/system-profiles/") + if not x.endswith("-link")] + else: + return [] + +def main(): + parser = argparse.ArgumentParser(description='Update NixOS-related systemd-boot files') + parser.add_argument('default_config', metavar='DEFAULT-CONFIG', help='The default NixOS config to boot') + args = parser.parse_args() + + try: + with open("/etc/machine-id") as machine_file: + machine_id = machine_file.readlines()[0] + except IOError as e: + if e.errno != errno.ENOENT: + raise + # Since systemd version 232 a machine ID is required and it might not + # be there on newly installed systems, so let's generate one so that + # bootctl can find it and we can also pass it to write_entry() later. + cmd = ["@systemd@/bin/systemd-machine-id-setup", "--print"] + machine_id = subprocess.check_output(cmd).rstrip() + + if os.getenv("NIXOS_INSTALL_GRUB") == "1": + warnings.warn("NIXOS_INSTALL_GRUB env var deprecated, use NIXOS_INSTALL_BOOTLOADER", DeprecationWarning) + os.environ["NIXOS_INSTALL_BOOTLOADER"] = "1" + + if os.getenv("NIXOS_INSTALL_BOOTLOADER") == "1": + # bootctl uses fopen() with modes "wxe" and fails if the file exists. + if os.path.exists("@efiSysMountPoint@/loader/loader.conf"): + os.unlink("@efiSysMountPoint@/loader/loader.conf") + + if "@canTouchEfiVariables@" == "1": + subprocess.check_call(["@systemd@/bin/bootctl", "--path=@efiSysMountPoint@", "install"]) + else: + subprocess.check_call(["@systemd@/bin/bootctl", "--path=@efiSysMountPoint@", "--no-variables", "install"]) + + mkdir_p("@efiSysMountPoint@/efi/nixos") + mkdir_p("@efiSysMountPoint@/loader/entries") + + gens = get_generations() + for profile in get_profiles(): + gens += get_generations(profile) + remove_old_entries(gens) + for gen in gens: + write_entry(*gen, machine_id) + if os.readlink(system_dir(*gen)) == args.default_config: + write_loader_conf(*gen) + + memtest_entry_file = "@efiSysMountPoint@/loader/entries/memtest86.conf" + if os.path.exists(memtest_entry_file): + os.unlink(memtest_entry_file) + shutil.rmtree("@efiSysMountPoint@/efi/memtest86", ignore_errors=True) + if "@memtest86@" != "": + mkdir_p("@efiSysMountPoint@/efi/memtest86") + for path in glob.iglob("@memtest86@/*"): + if os.path.isdir(path): + shutil.copytree(path, os.path.join("@efiSysMountPoint@/efi/memtest86", os.path.basename(path))) + else: + shutil.copy(path, "@efiSysMountPoint@/efi/memtest86/") + + memtest_entry_file = "@efiSysMountPoint@/loader/entries/memtest86.conf" + memtest_entry_file_tmp_path = "%s.tmp" % memtest_entry_file + with open(memtest_entry_file_tmp_path, 'w') as f: + f.write(MEMTEST_BOOT_ENTRY) + os.rename(memtest_entry_file_tmp_path, memtest_entry_file) + + # Since fat32 provides little recovery facilities after a crash, + # it can leave the system in an unbootable state, when a crash/outage + # happens shortly after an update. To decrease the likelihood of this + # event sync the efi filesystem after each update. + rc = libc.syncfs(os.open("@efiSysMountPoint@", os.O_RDONLY)) + if rc != 0: + print("could not sync @efiSysMountPoint@: {}".format(os.strerror(rc)), file=sys.stderr) + +if __name__ == '__main__': + main() |