diff options
Diffstat (limited to 'pkgs/os-specific/linux/kernel/update-hardened.py')
| -rwxr-xr-x | pkgs/os-specific/linux/kernel/update-hardened.py | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/pkgs/os-specific/linux/kernel/update-hardened.py b/pkgs/os-specific/linux/kernel/update-hardened.py new file mode 100755 index 0000000000000..089e991d06bcb --- /dev/null +++ b/pkgs/os-specific/linux/kernel/update-hardened.py @@ -0,0 +1,200 @@ +#! /usr/bin/env nix-shell +#! nix-shell -i python -p "python3.withPackages (ps: [ps.PyGithub])" git gnupg + +# This is automatically called by ./update.sh. + +import re +import json +import sys +import os.path +from glob import glob +import subprocess +from tempfile import TemporaryDirectory + +from github import Github + +HERE = os.path.dirname(os.path.realpath(__file__)) +HARDENED_GITHUB_REPO = 'anthraxx/linux-hardened' +HARDENED_TRUSTED_KEY = os.path.join(HERE, 'anthraxx.asc') +HARDENED_PATCHES_PATH = os.path.join(HERE, 'hardened-patches.json') +MIN_KERNEL = (4, 14) + +HARDENED_VERSION_RE = re.compile(r''' + (?P<kernel_version> [\d.]+) \. + (?P<version_suffix> [a-z]+) +''', re.VERBOSE) + +def parse_version(version): + match = HARDENED_VERSION_RE.fullmatch(version) + if match: + return match.groups() + +def run(*args, **kwargs): + try: + return subprocess.run( + args, **kwargs, + check=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE, + ) + except subprocess.CalledProcessError as err: + print( + f'error: `{err.cmd}` failed unexpectedly\n' + f'status code: {err.returncode}\n' + f'stdout:\n{err.stdout.decode("utf-8").strip()}\n' + f'stderr:\n{err.stderr.decode("utf-8").strip()}', + file=sys.stderr, + ) + sys.exit(1) + +def nix_prefetch_url(url): + output = run('nix-prefetch-url', '--print-path', url).stdout + return output.decode('utf-8').strip().split('\n') + +def verify_openpgp_signature(*, name, trusted_key, sig_path, data_path): + with TemporaryDirectory(suffix='.nixpkgs-gnupg-home') as gnupg_home: + run('gpg', '--homedir', gnupg_home, '--import', trusted_key) + keyring = os.path.join(gnupg_home, 'pubring.kbx') + try: + subprocess.run( + ('gpgv', '--keyring', keyring, sig_path, data_path), + check=True, stderr=subprocess.PIPE, + ) + return True + except subprocess.CalledProcessError as err: + print( + f'error: signature for {name} failed to verify!', + file=sys.stderr, + ) + print(err.stderr.decode('utf-8'), file=sys.stderr, end='') + return False + +def fetch_patch(*, name, release): + def find_asset(filename): + try: + return next( + asset.browser_download_url + for asset in release.get_assets() + if asset.name == filename + ) + except StopIteration: + raise KeyError(filename) + + try: + patch_url = find_asset(f'{name}.patch') + sig_url = find_asset(f'{name}.patch.sig') + except KeyError: + print(f'error: {name}.patch{{,sig}} not present', file=sys.stderr) + return None + + sha256, patch_path = nix_prefetch_url(patch_url) + _, sig_path = nix_prefetch_url(sig_url) + sig_ok = verify_openpgp_signature( + name=name, + trusted_key=HARDENED_TRUSTED_KEY, + sig_path=sig_path, + data_path=patch_path, + ) + if not sig_ok: + return None + + return { + 'url': patch_url, + 'sha256': sha256, + } + +def commit_patches(*, kernel_version, message): + with open(HARDENED_PATCHES_PATH + '.new', 'w') as new_patches_file: + json.dump(patches, new_patches_file, indent=4, sort_keys=True) + new_patches_file.write('\n') + os.rename(HARDENED_PATCHES_PATH + '.new', HARDENED_PATCHES_PATH) + message = f'linux/hardened-patches/{kernel_version}: {message}' + print(message) + if os.environ.get('COMMIT'): + run( + 'git', '-C', HERE, 'commit', f'--message={message}', + 'hardened-patches.json', + ) + +# Load the existing patches. +with open(HARDENED_PATCHES_PATH) as patches_file: + patches = json.load(patches_file) + +NIX_VERSION_RE = re.compile(r''' + \s* version \s* = + \s* " (?P<version> [^"]*) " + \s* ; \s* \n +''', re.VERBOSE) + +# Get the set of currently packaged kernel versions. +kernel_versions = set() +for filename in os.listdir(HERE): + filename_match = re.fullmatch(r'linux-(\d+)\.(\d+)\.nix', filename) + if filename_match: + if tuple(int(v) for v in filename_match.groups()) < MIN_KERNEL: + continue + with open(os.path.join(HERE, filename)) as nix_file: + for nix_line in nix_file: + match = NIX_VERSION_RE.fullmatch(nix_line) + if match: + kernel_versions.add(match.group('version')) + +# Remove patches for old kernel versions. +for kernel_version in patches.keys() - kernel_versions: + del patches[kernel_version] + commit_patches(kernel_version=kernel_version, message='remove') + +g = Github(os.environ.get('GITHUB_TOKEN')) +repo = g.get_repo(HARDENED_GITHUB_REPO) +releases = repo.get_releases() + +found_kernel_versions = set() +failures = False + +for release in releases: + remaining_kernel_versions = kernel_versions - found_kernel_versions + + if not remaining_kernel_versions: + break + + version = release.tag_name + name = f'linux-hardened-{version}' + version_info = parse_version(version) + if not version_info: + continue + kernel_version, version_suffix = version_info + + if kernel_version in remaining_kernel_versions: + found_kernel_versions.add(kernel_version) + try: + old_version_suffix = patches[kernel_version]['version_suffix'] + old_version = f'{kernel_version}.{old_version_suffix}' + update = old_version_suffix < version_suffix + except KeyError: + update = True + old_version = None + + if update: + patch = fetch_patch(name=name, release=release) + if patch is None: + failures = True + else: + patch['version_suffix'] = version_suffix + patches[kernel_version] = patch + if old_version: + message = f'{old_version} -> {version}' + else: + message = f'init at {version}' + commit_patches(kernel_version=kernel_version, message=message) + +missing_kernel_versions = kernel_versions - patches.keys() + +if missing_kernel_versions: + print( + f'warning: no patches for kernel versions ' + + ', '.join(missing_kernel_versions) + + '\nwarning: consider manually backporting older patches (bump ' + 'JSON key, set version_suffix to "NixOS-a")', + file=sys.stderr, + ) + +if failures: + sys.exit(1) |