X-Git-Url: https://jxself.org/git/?a=blobdiff_plain;f=kernel_hardening_checker%2F__init__.py;h=67e02690bee12aa8b6934f5ec3c7ee91cab044c0;hb=20c636e47eaabf1cc40aad99d3138ffbb0a27f2f;hp=212cf620dd78dd7722e17f2a0cc59f27d4f0cb8e;hpb=5a298be1e2af5e952cfd069e86c2de5c47bd4205;p=kconfig-hardened-check.git diff --git a/kernel_hardening_checker/__init__.py b/kernel_hardening_checker/__init__.py index 212cf62..67e0269 100644 --- a/kernel_hardening_checker/__init__.py +++ b/kernel_hardening_checker/__init__.py @@ -8,29 +8,35 @@ Author: Alexander Popov This module performs input/output. """ -# pylint: disable=missing-function-docstring,line-too-long,invalid-name,too-many-branches,too-many-statements +# pylint: disable=missing-function-docstring,line-too-long,too-many-branches,too-many-statements +import os import gzip import sys from argparse import ArgumentParser -from collections import OrderedDict +from typing import List, Tuple, Dict, TextIO import re import json -from .__about__ import __version__ from .checks import add_kconfig_checks, add_cmdline_checks, normalize_cmdline_options, add_sysctl_checks -from .engine import populate_with_data, perform_checks, override_expected_value +from .engine import StrOrNone, TupleOrNone, ChecklistObjType +from .engine import print_unknown_options, populate_with_data, perform_checks, override_expected_value -def _open(file: str, *args, **kwargs): - open_method = open - if file.endswith(".gz"): - open_method = gzip.open +# kernel-hardening-checker version +__version__ = '0.6.6' - return open_method(file, *args, **kwargs) +def _open(file: str) -> TextIO: + try: + if file.endswith('.gz'): + return gzip.open(file, 'rt', encoding='utf-8') + return open(file, 'rt', encoding='utf-8') + except FileNotFoundError: + sys.exit(f'[!] ERROR: unable to open {file}, are you sure it exists?') -def detect_arch(fname, archs): - with _open(fname, 'rt', encoding='utf-8') as f: + +def detect_arch(fname: str, archs: List[str]) -> Tuple[StrOrNone, str]: + with _open(fname) as f: arch_pattern = re.compile(r"CONFIG_[a-zA-Z0-9_]+=y$") arch = None for line in f.readlines(): @@ -46,26 +52,27 @@ def detect_arch(fname, archs): return arch, 'OK' -def detect_kernel_version(fname): - with _open(fname, 'rt', encoding='utf-8') as f: +def detect_kernel_version(fname: str) -> Tuple[TupleOrNone, str]: + with _open(fname) as f: ver_pattern = re.compile(r"^# Linux/.+ Kernel Configuration$|^Linux version .+") for line in f.readlines(): if ver_pattern.match(line): line = line.strip() parts = line.split() - ver_str = parts[2] + ver_str = parts[2].split('-', 1)[0] ver_numbers = ver_str.split('.') - if len(ver_numbers) < 3 or not ver_numbers[0].isdigit() or not ver_numbers[1].isdigit(): - msg = f'failed to parse the version "{ver_str}"' - return None, msg - return (int(ver_numbers[0]), int(ver_numbers[1])), None + if len(ver_numbers) >= 3: + if all(map(lambda x: x.isdecimal(), ver_numbers)): + return tuple(map(int, ver_numbers)), 'OK' + msg = f'failed to parse the version "{parts[2]}"' + return None, msg return None, 'no kernel version detected' -def detect_compiler(fname): +def detect_compiler(fname: str) -> Tuple[StrOrNone, str]: gcc_version = None clang_version = None - with _open(fname, 'rt', encoding='utf-8') as f: + with _open(fname) as f: for line in f.readlines(): if line.startswith('CONFIG_GCC_VERSION='): gcc_version = line[19:-1] @@ -74,36 +81,13 @@ def detect_compiler(fname): if gcc_version is None or clang_version is None: return None, 'no CONFIG_GCC_VERSION or CONFIG_CLANG_VERSION' if gcc_version == '0' and clang_version != '0': - return 'CLANG ' + clang_version, 'OK' + return f'CLANG {clang_version}', 'OK' if gcc_version != '0' and clang_version == '0': - return 'GCC ' + gcc_version, 'OK' + return f'GCC {gcc_version}', 'OK' sys.exit(f'[!] ERROR: invalid GCC_VERSION and CLANG_VERSION: {gcc_version} {clang_version}') -def print_unknown_options(checklist, parsed_options, opt_type): - known_options = [] - - for o1 in checklist: - if o1.type != 'complex': - known_options.append(o1.name) - continue - for o2 in o1.opts: - if o2.type != 'complex': - if hasattr(o2, 'name'): - known_options.append(o2.name) - continue - for o3 in o2.opts: - assert(o3.type != 'complex'), \ - f'unexpected ComplexOptCheck inside {o2.name}' - if hasattr(o3, 'name'): - known_options.append(o3.name) - - for option, value in parsed_options.items(): - if option not in known_options: - print(f'[?] No check for {opt_type} option {option} ({value})') - - -def print_checklist(mode, checklist, with_results): +def print_checklist(mode: StrOrNone, checklist: List[ChecklistObjType], with_results: bool) -> None: if mode == 'json': output = [] for opt in checklist: @@ -116,21 +100,28 @@ def print_checklist(mode, checklist, with_results): if with_results: sep_line_len += 30 print('=' * sep_line_len) - print(f'{"option name":^40}|{"type":^7}|{"desired val":^12}|{"decision":^10}|{"reason":^18}', end='') + print(f'{"option_name":^40}|{"type":^7}|{"desired_val":^12}|{"decision":^10}|{"reason":^18}', end='') if with_results: - print('| check result', end='') + print('| check_result', end='') print() print('=' * sep_line_len) # table contents + ok_count = 0 + fail_count = 0 for opt in checklist: if with_results: - if mode == 'show_ok': - if not opt.result.startswith('OK'): + assert(opt.result), f'unexpected empty result of {opt.name} check' + if opt.result.startswith('OK'): + ok_count += 1 + if mode == 'show_fail': continue - if mode == 'show_fail': - if not opt.result.startswith('FAIL'): + elif opt.result.startswith('FAIL'): + fail_count += 1 + if mode == 'show_ok': continue + else: + assert(False), f'unexpected result "{opt.result}" of {opt.name} check' opt.table_print(mode, with_results) print() if mode == 'verbose': @@ -139,9 +130,7 @@ def print_checklist(mode, checklist, with_results): # final score if with_results: - fail_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), checklist))) fail_suppressed = '' - ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), checklist))) ok_suppressed = '' if mode == 'show_ok': fail_suppressed = ' (suppressed in output)' @@ -150,8 +139,8 @@ def print_checklist(mode, checklist, with_results): print(f'[+] Config check is finished: \'OK\' - {ok_count}{ok_suppressed} / \'FAIL\' - {fail_count}{fail_suppressed}') -def parse_kconfig_file(mode, parsed_options, fname): - with _open(fname, 'rt', encoding='utf-8') as f: +def parse_kconfig_file(_mode: StrOrNone, parsed_options: Dict[str, str], fname: str) -> None: + with _open(fname) as f: opt_is_on = re.compile(r"CONFIG_[a-zA-Z0-9_]+=.+$") opt_is_off = re.compile(r"# CONFIG_[a-zA-Z0-9_]+ is not set$") @@ -175,10 +164,14 @@ def parse_kconfig_file(mode, parsed_options, fname): sys.exit(f'[!] ERROR: Kconfig option "{line}" is found multiple times') if option: + assert(value), f'unexpected empty value for {option}' parsed_options[option] = value -def parse_cmdline_file(mode, parsed_options, fname): +def parse_cmdline_file(mode: StrOrNone, parsed_options: Dict[str, str], fname: str) -> None: + if not os.path.isfile(fname): + sys.exit(f'[!] ERROR: unable to open {fname}, are you sure it exists?') + with open(fname, 'r', encoding='utf-8') as f: line = f.readline() opts = line.split() @@ -196,10 +189,14 @@ def parse_cmdline_file(mode, parsed_options, fname): if name in parsed_options and mode != 'json': print(f'[!] WARNING: cmdline option "{name}" is found multiple times') value = normalize_cmdline_options(name, value) + assert(value is not None), f'unexpected None value for {name}' parsed_options[name] = value -def parse_sysctl_file(mode, parsed_options, fname): +def parse_sysctl_file(mode: StrOrNone, parsed_options: Dict[str, str], fname: str) -> None: + if not os.path.isfile(fname): + sys.exit(f'[!] ERROR: unable to open {fname}, are you sure it exists?') + with open(fname, 'r', encoding='utf-8') as f: sysctl_pattern = re.compile(r"[a-zA-Z0-9/\._-]+ =.*$") for line in f.readlines(): @@ -218,11 +215,11 @@ def parse_sysctl_file(mode, parsed_options, fname): sys.exit(f'[!] ERROR: {fname} doesn\'t look like a sysctl output file, please try `sudo sysctl -a > {fname}`') # let's check the presence of a sysctl option available for root - if 'net.core.bpf_jit_harden' not in parsed_options and mode != 'json': - print(f'[!] WARNING: sysctl option "net.core.bpf_jit_harden" available for root is not found in {fname}, please try `sudo sysctl -a > {fname}`') + if 'kernel.cad_pid' not in parsed_options and mode != 'json': + print(f'[!] WARNING: sysctl option "kernel.cad_pid" available for root is not found in {fname}, please try `sudo sysctl -a > {fname}`') -def main(): +def main() -> None: # Report modes: # * verbose mode for # - reporting about unknown kernel options in the Kconfig @@ -232,7 +229,7 @@ def main(): supported_archs = ['X86_64', 'X86_32', 'ARM64', 'ARM'] parser = ArgumentParser(prog='kernel-hardening-checker', description='A tool for checking the security hardening options of the Linux kernel') - parser.add_argument('--version', action='version', version='%(prog)s ' + __version__) + parser.add_argument('--version', action='version', version=f'%(prog)s {__version__}') parser.add_argument('-m', '--mode', choices=report_modes, help='choose the report mode') parser.add_argument('-c', '--config', @@ -255,7 +252,7 @@ def main(): if mode != 'json': print(f'[+] Special report mode: {mode}') - config_checklist = [] + config_checklist = [] # type: List[ChecklistObjType] if args.config: if args.print: @@ -281,11 +278,11 @@ def main(): else: kernel_version, msg = detect_kernel_version(args.config) if kernel_version is None: - if not args.kernel_version: + if args.kernel_version is None: print('[!] Hint: provide the kernel version file through --kernel-version option') sys.exit(f'[!] ERROR: {msg}') if mode != 'json': - print(f'[+] Detected kernel version: {kernel_version[0]}.{kernel_version[1]}') + print(f'[+] Detected kernel version: {kernel_version}') compiler, msg = detect_compiler(args.config) if mode != 'json': @@ -306,7 +303,7 @@ def main(): add_sysctl_checks(config_checklist, arch) # populate the checklist with the parsed Kconfig data - parsed_kconfig_options = OrderedDict() + parsed_kconfig_options = {} # type: Dict[str, str] parse_kconfig_file(mode, parsed_kconfig_options, args.config) populate_with_data(config_checklist, parsed_kconfig_options, 'kconfig') @@ -315,13 +312,13 @@ def main(): if args.cmdline: # populate the checklist with the parsed cmdline data - parsed_cmdline_options = OrderedDict() + parsed_cmdline_options = {} # type: Dict[str, str] parse_cmdline_file(mode, parsed_cmdline_options, args.cmdline) populate_with_data(config_checklist, parsed_cmdline_options, 'cmdline') if args.sysctl: # populate the checklist with the parsed sysctl data - parsed_sysctl_options = OrderedDict() + parsed_sysctl_options = {} # type: Dict[str, str] parse_sysctl_file(mode, parsed_sysctl_options, args.sysctl) populate_with_data(config_checklist, parsed_sysctl_options, 'sysctl') @@ -329,6 +326,11 @@ def main(): mmap_rnd_bits_max = parsed_kconfig_options.get('CONFIG_ARCH_MMAP_RND_BITS_MAX', None) if mmap_rnd_bits_max: override_expected_value(config_checklist, 'CONFIG_ARCH_MMAP_RND_BITS', mmap_rnd_bits_max) + else: + # remove the CONFIG_ARCH_MMAP_RND_BITS check to avoid false results + if mode != 'json': + print('[-] Can\'t check CONFIG_ARCH_MMAP_RND_BITS without CONFIG_ARCH_MMAP_RND_BITS_MAX') + config_checklist[:] = [o for o in config_checklist if o.name != 'CONFIG_ARCH_MMAP_RND_BITS'] # now everything is ready, perform the checks perform_checks(config_checklist) @@ -361,7 +363,7 @@ def main(): add_sysctl_checks(config_checklist, None) # populate the checklist with the parsed sysctl data - parsed_sysctl_options = OrderedDict() + parsed_sysctl_options = {} parse_sysctl_file(mode, parsed_sysctl_options, args.sysctl) populate_with_data(config_checklist, parsed_sysctl_options, 'sysctl') @@ -383,6 +385,7 @@ def main(): if mode and mode not in ('verbose', 'json'): sys.exit(f'[!] ERROR: wrong mode "{mode}" for --print') arch = args.print + assert(arch), 'unexpected empty arch from ArgumentParser' add_kconfig_checks(config_checklist, arch) add_cmdline_checks(config_checklist, arch) add_sysctl_checks(config_checklist, arch) @@ -392,15 +395,22 @@ def main(): sys.exit(0) if args.generate: - assert(args.config is None and args.cmdline is None and args.sysctl is None and args.print is None), 'unexpected args' + assert(args.config is None and + args.cmdline is None and + args.sysctl is None and + args.print is None), \ + 'unexpected args' if mode: sys.exit(f'[!] ERROR: wrong mode "{mode}" for --generate') arch = args.generate + assert(arch), 'unexpected empty arch from ArgumentParser' add_kconfig_checks(config_checklist, arch) print(f'CONFIG_{arch}=y') # the Kconfig fragment should describe the microarchitecture for opt in config_checklist: if opt.name == 'CONFIG_ARCH_MMAP_RND_BITS': continue # don't add CONFIG_ARCH_MMAP_RND_BITS because its value needs refinement + if opt.expected == 'is not off': + continue # don't add Kconfig options without explicitly recommended values if opt.expected == 'is not set': print(f'# {opt.name} is not set') else: