4 # This tool helps me to check Linux kernel options against
5 # my security hardening preferences for X86_64, ARM64, X86_32, and ARM.
6 # Let the computers do their job!
8 # Author: Alexander Popov <alex.popov@linux.com>
10 # Please don't cry if my Python code looks like C.
13 # N.B Hardening command line parameters:
14 # iommu=force (does it help against DMA attacks?)
17 # Mitigations of CPU vulnerabilities:
19 # mitigations=auto,nosmt (nosmt is slow)
21 # spec_store_bypass_disable=on
23 # l1d_flush=on (a part of the l1tf option)
31 # sysrq_always_enabled
36 # Hardware tag-based KASAN with arm64 Memory Tagging Extension (MTE):
38 # kasan.stacktrace=off
41 # N.B. Hardening sysctls:
42 # kernel.kptr_restrict=2 (or 1?)
43 # kernel.dmesg_restrict=1 (also see the kconfig option)
44 # kernel.perf_event_paranoid=3
45 # kernel.kexec_load_disabled=1
46 # kernel.yama.ptrace_scope=3
47 # user.max_user_namespaces=0
48 # what about bpf_jit_enable?
49 # kernel.unprivileged_bpf_disabled=1
50 # net.core.bpf_jit_harden=2
51 # vm.unprivileged_userfaultfd=0
52 # (at first, it disabled unprivileged userfaultfd,
53 # and since v5.11 it enables unprivileged userfaultfd for user-mode only)
54 # vm.mmap_min_addr has a good value
55 # dev.tty.ldisc_autoload=0
56 # fs.protected_symlinks=1
57 # fs.protected_hardlinks=1
58 # fs.protected_fifos=2
59 # fs.protected_regular=2
61 # kernel.modules_disabled=1
62 # kernel.randomize_va_space = 2
65 # pylint: disable=missing-module-docstring,missing-class-docstring,missing-function-docstring
66 # pylint: disable=line-too-long,invalid-name,too-many-branches,too-many-statements
70 from argparse import ArgumentParser
71 from collections import OrderedDict
74 from .__about__ import __version__
76 SIMPLE_OPTION_TYPES = ('kconfig', 'version', 'cmdline')
79 # Constructor without the 'expected' parameter is for option presence checks (any value is OK)
80 def __init__(self, reason, decision, name, expected=None):
81 assert(reason and decision and name), \
82 'invalid {} check for "{}"'.format(self.__class__.__name__, name)
84 self.expected = expected
85 self.decision = decision
95 # handle the option presence check
96 if self.expected is None:
97 if self.state is None:
98 self.result = 'FAIL: not present'
100 self.result = 'OK: is present'
103 # handle the option value check
104 if self.expected == self.state:
106 elif self.state is None:
107 if self.expected == 'is not set':
108 self.result = 'OK: not found'
110 self.result = 'FAIL: not found'
112 self.result = 'FAIL: "' + self.state + '"'
114 def table_print(self, _mode, with_results):
115 if self.expected is None:
118 expected = self.expected
119 print('{:<40}|{:^7}|{:^12}|{:^10}|{:^18}'.format(self.name, self.type, expected, self.decision, self.reason), end='')
121 print('| {}'.format(self.result), end='')
123 def json_dump(self, with_results):
124 dump = [self.name, self.type, self.expected, self.decision, self.reason]
126 dump.append(self.result)
130 class KconfigCheck(OptCheck):
131 def __init__(self, *args, **kwargs):
132 super().__init__(*args, **kwargs)
133 self.name = 'CONFIG_' + self.name
140 class CmdlineCheck(OptCheck):
147 def __init__(self, ver_expected):
148 self.ver_expected = ver_expected
157 if self.ver[0] > self.ver_expected[0]:
158 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
160 if self.ver[0] < self.ver_expected[0]:
161 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
163 if self.ver[1] >= self.ver_expected[1]:
164 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
166 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
168 def table_print(self, _mode, with_results):
169 ver_req = 'kernel version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
170 print('{:<91}'.format(ver_req), end='')
172 print('| {}'.format(self.result), end='')
175 class ComplexOptCheck:
176 def __init__(self, *opts):
179 'empty {} check'.format(self.__class__.__name__)
180 assert(len(self.opts) != 1), \
181 'useless {} check: {}'.format(self.__class__.__name__, opts)
182 assert(isinstance(opts[0], (KconfigCheck, CmdlineCheck))), \
183 'invalid {} check: {}'.format(self.__class__.__name__, opts)
192 return self.opts[0].name
196 return self.opts[0].expected
198 def table_print(self, mode, with_results):
199 if mode == 'verbose':
200 print(' {:87}'.format('<<< ' + self.__class__.__name__ + ' >>>'), end='')
202 print('| {}'.format(self.result), end='')
205 o.table_print(mode, with_results)
208 o.table_print(mode, False)
210 print('| {}'.format(self.result), end='')
212 def json_dump(self, with_results):
213 dump = self.opts[0].json_dump(False)
215 dump.append(self.result)
219 class OR(ComplexOptCheck):
220 # self.opts[0] is the option that this OR-check is about.
222 # OR(<X_is_hardened>, <X_is_disabled>)
223 # OR(<X_is_hardened>, <old_X_is_hardened>)
225 for i, opt in enumerate(self.opts):
227 if opt.result.startswith('OK'):
228 self.result = opt.result
229 # Add more info for additional checks:
231 if opt.result == 'OK':
232 self.result = 'OK: {} "{}"'.format(opt.name, opt.expected)
233 elif opt.result == 'OK: not found':
234 self.result = 'OK: {} not found'.format(opt.name)
235 elif opt.result == 'OK: is present':
236 self.result = 'OK: {} is present'.format(opt.name)
238 # VersionCheck provides enough info
239 assert(opt.result.startswith('OK: version')), \
240 'unexpected OK description "{}"'.format(opt.result)
242 self.result = self.opts[0].result
245 class AND(ComplexOptCheck):
246 # self.opts[0] is the option that this AND-check is about.
248 # AND(<suboption>, <main_option>)
249 # Suboption is not checked if checking of the main_option is failed.
250 # AND(<X_is_disabled>, <old_X_is_disabled>)
252 for i, opt in reversed(list(enumerate(self.opts))):
255 self.result = opt.result
257 if not opt.result.startswith('OK'):
258 # This FAIL is caused by additional checks,
259 # and not by the main option that this AND-check is about.
260 # Describe the reason of the FAIL.
261 if opt.result.startswith('FAIL: \"') or opt.result == 'FAIL: not found':
262 self.result = 'FAIL: {} not "{}"'.format(opt.name, opt.expected)
263 elif opt.result == 'FAIL: not present':
264 self.result = 'FAIL: {} not present'.format(opt.name)
266 # VersionCheck provides enough info
267 self.result = opt.result
268 assert(opt.result.startswith('FAIL: version')), \
269 'unexpected FAIL description "{}"'.format(opt.result)
273 def detect_arch(fname, archs):
274 with open(fname, 'r') as f:
275 arch_pattern = re.compile("CONFIG_[a-zA-Z0-9_]*=y")
277 for line in f.readlines():
278 if arch_pattern.match(line):
279 option, _ = line[7:].split('=', 1)
284 return None, 'more than one supported architecture is detected'
286 return None, 'failed to detect architecture'
290 def detect_kernel_version(fname):
291 with open(fname, 'r') as f:
292 ver_pattern = re.compile("# Linux/.* Kernel Configuration")
293 for line in f.readlines():
294 if ver_pattern.match(line):
298 ver_numbers = ver_str.split('.')
299 if len(ver_numbers) < 3 or not ver_numbers[0].isdigit() or not ver_numbers[1].isdigit():
300 msg = 'failed to parse the version "' + ver_str + '"'
302 return (int(ver_numbers[0]), int(ver_numbers[1])), None
303 return None, 'no kernel version detected'
306 def detect_compiler(fname):
309 with open(fname, 'r') as f:
310 gcc_version_pattern = re.compile("CONFIG_GCC_VERSION=[0-9]*")
311 clang_version_pattern = re.compile("CONFIG_CLANG_VERSION=[0-9]*")
312 for line in f.readlines():
313 if gcc_version_pattern.match(line):
314 gcc_version = line[19:-1]
315 if clang_version_pattern.match(line):
316 clang_version = line[21:-1]
317 if not gcc_version or not clang_version:
318 return None, 'no CONFIG_GCC_VERSION or CONFIG_CLANG_VERSION'
319 if gcc_version == '0' and clang_version != '0':
320 return 'CLANG ' + clang_version, 'OK'
321 if gcc_version != '0' and clang_version == '0':
322 return 'GCC ' + gcc_version, 'OK'
323 sys.exit('[!] ERROR: invalid GCC_VERSION and CLANG_VERSION: {} {}'.format(gcc_version, clang_version))
326 def add_kconfig_checks(l, arch):
327 # Calling the KconfigCheck class constructor:
328 # KconfigCheck(reason, decision, name, expected)
330 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
331 # when the tool doesn't check the cmdline.
333 efi_not_set = KconfigCheck('-', '-', 'EFI', 'is not set')
334 cc_is_gcc = KconfigCheck('-', '-', 'CC_IS_GCC', 'y') # exists since v4.18
335 cc_is_clang = KconfigCheck('-', '-', 'CC_IS_CLANG', 'y') # exists since v4.18
337 modules_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'MODULES', 'is not set')
338 devmem_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'DEVMEM', 'is not set') # refers to LOCKDOWN
339 bpf_syscall_not_set = KconfigCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set') # refers to LOCKDOWN
341 # 'self_protection', 'defconfig'
342 l += [KconfigCheck('self_protection', 'defconfig', 'BUG', 'y')]
343 l += [KconfigCheck('self_protection', 'defconfig', 'SLUB_DEBUG', 'y')]
344 gcc_plugins_support_is_set = KconfigCheck('self_protection', 'defconfig', 'GCC_PLUGINS', 'y')
345 l += [gcc_plugins_support_is_set]
346 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR', 'y'),
347 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR', 'y'),
348 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_REGULAR', 'y'),
349 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_AUTO', 'y'),
350 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
351 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_STRONG', 'y'),
352 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
353 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_KERNEL_RWX', 'y'),
354 KconfigCheck('self_protection', 'defconfig', 'DEBUG_RODATA', 'y'))] # before v4.11
355 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_MODULE_RWX', 'y'),
356 KconfigCheck('self_protection', 'defconfig', 'DEBUG_SET_MODULE_RONX', 'y'),
357 modules_not_set)] # DEBUG_SET_MODULE_RONX was before v4.11
358 l += [OR(KconfigCheck('self_protection', 'defconfig', 'REFCOUNT_FULL', 'y'),
359 VersionCheck((5, 5)))] # REFCOUNT_FULL is enabled by default since v5.5
360 l += [KconfigCheck('self_protection', 'defconfig', 'THREAD_INFO_IN_TASK', 'y')]
361 iommu_support_is_set = KconfigCheck('self_protection', 'defconfig', 'IOMMU_SUPPORT', 'y')
362 l += [iommu_support_is_set] # is needed for mitigating DMA attacks
363 if arch in ('X86_64', 'ARM64', 'X86_32'):
364 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y')]
365 if arch in ('X86_64', 'ARM64'):
366 l += [KconfigCheck('self_protection', 'defconfig', 'VMAP_STACK', 'y')]
367 if arch in ('X86_64', 'X86_32'):
368 l += [KconfigCheck('self_protection', 'defconfig', 'MICROCODE', 'y')] # is needed for mitigating CPU bugs
369 l += [KconfigCheck('self_protection', 'defconfig', 'RETPOLINE', 'y')]
370 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_SMAP', 'y'),
371 VersionCheck((5, 19)))] # X86_SMAP is enabled by default since v5.19
372 l += [KconfigCheck('self_protection', 'defconfig', 'SYN_COOKIES', 'y')] # another reason?
373 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_UMIP', 'y'),
374 KconfigCheck('self_protection', 'defconfig', 'X86_INTEL_UMIP', 'y'))]
375 if arch in ('ARM64', 'ARM'):
376 l += [KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_PER_TASK', 'y')]
378 l += [KconfigCheck('self_protection', 'defconfig', 'PAGE_TABLE_ISOLATION', 'y')]
379 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MEMORY', 'y')]
380 l += [AND(KconfigCheck('self_protection', 'defconfig', 'INTEL_IOMMU', 'y'),
381 iommu_support_is_set)]
382 l += [AND(KconfigCheck('self_protection', 'defconfig', 'AMD_IOMMU', 'y'),
383 iommu_support_is_set)]
385 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PAN', 'y')]
386 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_EPAN', 'y')]
387 l += [KconfigCheck('self_protection', 'defconfig', 'UNMAP_KERNEL_AT_EL0', 'y')]
388 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_EL2_VECTORS', 'y'),
389 AND(KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y'),
390 VersionCheck((5, 9))))] # HARDEN_EL2_VECTORS was included in RANDOMIZE_BASE in v5.9
391 l += [KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y')]
392 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PTR_AUTH_KERNEL', 'y')]
393 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_BTI_KERNEL', 'y')]
394 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y'),
395 VersionCheck((5, 10)))] # HARDEN_BRANCH_PREDICTOR is enabled by default since v5.10
396 l += [KconfigCheck('self_protection', 'defconfig', 'MITIGATE_SPECTRE_BRANCH_HISTORY', 'y')]
397 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_MTE', 'y')]
398 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MODULE_REGION_FULL', 'y')]
400 l += [KconfigCheck('self_protection', 'defconfig', 'CPU_SW_DOMAIN_PAN', 'y')]
401 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y')]
402 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_HISTORY', 'y')]
404 # 'self_protection', 'kspp'
405 l += [KconfigCheck('self_protection', 'kspp', 'BUG_ON_DATA_CORRUPTION', 'y')]
406 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_WX', 'y')]
407 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_STACK_END_CHECK', 'y')]
408 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_HARDENED', 'y')]
409 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_RANDOM', 'y')]
410 l += [KconfigCheck('self_protection', 'kspp', 'SHUFFLE_PAGE_ALLOCATOR', 'y')]
411 l += [KconfigCheck('self_protection', 'kspp', 'FORTIFY_SOURCE', 'y')]
412 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_LIST', 'y')]
413 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_SG', 'y')]
414 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_CREDENTIALS', 'y')]
415 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_NOTIFIERS', 'y')]
416 l += [KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y')]
417 l += [AND(KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_LATENT_ENTROPY', 'y'),
418 gcc_plugins_support_is_set)]
419 l += [KconfigCheck('self_protection', 'kspp', 'KFENCE', 'y')]
420 l += [KconfigCheck('self_protection', 'kspp', 'WERROR', 'y')]
421 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y')]
422 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set')] # true if IOMMU_DEFAULT_DMA_STRICT is set
423 l += [KconfigCheck('self_protection', 'kspp', 'ZERO_CALL_USED_REGS', 'y')]
424 randstruct_is_set = OR(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_FULL', 'y'),
425 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT', 'y'))
426 l += [randstruct_is_set]
427 hardened_usercopy_is_set = KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y')
428 l += [hardened_usercopy_is_set]
429 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
430 hardened_usercopy_is_set)]
431 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_PAGESPAN', 'is not set'),
432 hardened_usercopy_is_set)]
433 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG', 'y'),
435 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_ALL', 'y'),
437 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_SHA512', 'y'),
439 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_FORCE', 'y'),
440 modules_not_set)] # refers to LOCKDOWN
441 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_STACK_ALL_ZERO', 'y'),
442 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y'))]
443 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
444 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'))]
445 # CONFIG_INIT_ON_FREE_DEFAULT_ON was added in v5.3.
446 # CONFIG_PAGE_POISONING_ZERO was removed in v5.11.
447 # Starting from v5.11 CONFIG_PAGE_POISONING unconditionally checks
448 # the 0xAA poison pattern on allocation.
449 # That brings higher performance penalty.
450 if arch in ('X86_64', 'ARM64', 'X86_32'):
451 stackleak_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STACKLEAK', 'y')
452 l += [AND(stackleak_is_set, gcc_plugins_support_is_set)]
453 l += [KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y')]
454 if arch in ('X86_64', 'X86_32'):
455 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_CORE', 'y')]
456 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '65536')]
457 if arch in ('ARM64', 'ARM'):
458 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '32768')]
459 l += [KconfigCheck('self_protection', 'kspp', 'SYN_COOKIES', 'y')] # another reason?
461 l += [KconfigCheck('self_protection', 'kspp', 'ARM64_SW_TTBR0_PAN', 'y')]
463 l += [KconfigCheck('self_protection', 'kspp', 'PAGE_TABLE_ISOLATION', 'y')]
464 l += [KconfigCheck('self_protection', 'kspp', 'HIGHMEM64G', 'y')]
465 l += [KconfigCheck('self_protection', 'kspp', 'X86_PAE', 'y')]
467 # 'self_protection', 'maintainer'
468 ubsan_bounds_is_set = KconfigCheck('self_protection', 'maintainer', 'UBSAN_BOUNDS', 'y') # only array index bounds checking
469 l += [ubsan_bounds_is_set] # recommended by Kees Cook in /issues/53
470 if arch in ('X86_64', 'ARM64', 'X86_32'): # ARCH_HAS_UBSAN_SANITIZE_ALL is not enabled for ARM
471 l += [AND(KconfigCheck('self_protection', 'maintainer', 'UBSAN_SANITIZE_ALL', 'y'),
472 ubsan_bounds_is_set)] # recommended by Kees Cook in /issues/53
473 l += [AND(KconfigCheck('self_protection', 'maintainer', 'UBSAN_TRAP', 'y'),
474 ubsan_bounds_is_set)] # recommended by Kees Cook in /issues/53
476 # 'self_protection', 'clipos'
477 l += [KconfigCheck('self_protection', 'clipos', 'DEBUG_VIRTUAL', 'y')]
478 l += [KconfigCheck('self_protection', 'clipos', 'STATIC_USERMODEHELPER', 'y')] # needs userspace support
479 l += [OR(KconfigCheck('self_protection', 'clipos', 'EFI_DISABLE_PCI_DMA', 'y'),
481 l += [KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set')]
482 l += [KconfigCheck('self_protection', 'clipos', 'RANDOM_TRUST_BOOTLOADER', 'is not set')]
483 l += [KconfigCheck('self_protection', 'clipos', 'RANDOM_TRUST_CPU', 'is not set')]
484 l += [AND(KconfigCheck('self_protection', 'clipos', 'RANDSTRUCT_PERFORMANCE', 'is not set'),
485 KconfigCheck('self_protection', 'clipos', 'GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set'),
487 if arch in ('X86_64', 'ARM64', 'X86_32'):
488 l += [AND(KconfigCheck('self_protection', 'clipos', 'STACKLEAK_METRICS', 'is not set'),
490 gcc_plugins_support_is_set)]
491 l += [AND(KconfigCheck('self_protection', 'clipos', 'STACKLEAK_RUNTIME_DISABLE', 'is not set'),
493 gcc_plugins_support_is_set)]
494 if arch in ('X86_64', 'X86_32'):
495 l += [AND(KconfigCheck('self_protection', 'clipos', 'INTEL_IOMMU_DEFAULT_ON', 'y'),
496 iommu_support_is_set)]
498 l += [AND(KconfigCheck('self_protection', 'clipos', 'INTEL_IOMMU_SVM', 'y'),
499 iommu_support_is_set)]
501 l += [AND(KconfigCheck('self_protection', 'clipos', 'INTEL_IOMMU', 'y'),
502 iommu_support_is_set)]
504 # 'self_protection', 'my'
505 l += [OR(KconfigCheck('self_protection', 'my', 'RESET_ATTACK_MITIGATION', 'y'),
506 efi_not_set)] # needs userspace support (systemd)
507 l += [OR(KconfigCheck('self_protection', 'my', 'UBSAN_LOCAL_BOUNDS', 'y'),
508 AND(ubsan_bounds_is_set,
511 l += [KconfigCheck('self_protection', 'my', 'SLS', 'y')] # vs CVE-2021-26341 in Straight-Line-Speculation
512 l += [AND(KconfigCheck('self_protection', 'my', 'AMD_IOMMU_V2', 'y'),
513 iommu_support_is_set)]
515 l += [KconfigCheck('self_protection', 'my', 'SHADOW_CALL_STACK', 'y')] # maybe it's alternative to STACKPROTECTOR_STRONG
516 l += [KconfigCheck('self_protection', 'my', 'KASAN_HW_TAGS', 'y')]
517 cfi_clang_is_set = KconfigCheck('self_protection', 'my', 'CFI_CLANG', 'y')
518 l += [cfi_clang_is_set]
519 l += [AND(KconfigCheck('self_protection', 'my', 'CFI_PERMISSIVE', 'is not set'),
523 if arch in ('X86_64', 'ARM64', 'X86_32'):
524 l += [KconfigCheck('security_policy', 'defconfig', 'SECURITY', 'y')] # and choose your favourite LSM
526 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY', 'y')] # and choose your favourite LSM
527 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_YAMA', 'y')]
528 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LANDLOCK', 'y')]
529 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DISABLE', 'is not set')]
530 l += [KconfigCheck('security_policy', 'clipos', 'SECURITY_LOCKDOWN_LSM', 'y')]
531 l += [KconfigCheck('security_policy', 'clipos', 'SECURITY_LOCKDOWN_LSM_EARLY', 'y')]
532 l += [KconfigCheck('security_policy', 'clipos', 'LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y')]
533 l += [KconfigCheck('security_policy', 'my', 'SECURITY_WRITABLE_HOOKS', 'is not set')] # refers to SECURITY_SELINUX_DISABLE
534 l += [KconfigCheck('security_policy', 'my', 'SECURITY_SAFESETID', 'y')]
535 loadpin_is_set = KconfigCheck('security_policy', 'my', 'SECURITY_LOADPIN', 'y')
536 l += [loadpin_is_set] # needs userspace support
537 l += [AND(KconfigCheck('security_policy', 'my', 'SECURITY_LOADPIN_ENFORCE', 'y'),
540 # 'cut_attack_surface', 'defconfig'
541 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'BPF_UNPRIV_DEFAULT_OFF', 'y'),
542 bpf_syscall_not_set)] # see unprivileged_bpf_disabled
543 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP', 'y')]
544 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP_FILTER', 'y')]
545 if arch in ('X86_64', 'ARM64', 'X86_32'):
546 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'STRICT_DEVMEM', 'y'),
547 devmem_not_set)] # refers to LOCKDOWN
549 # 'cut_attack_surface', 'kspp'
550 l += [KconfigCheck('cut_attack_surface', 'kspp', 'SECURITY_DMESG_RESTRICT', 'y')]
551 l += [KconfigCheck('cut_attack_surface', 'kspp', 'ACPI_CUSTOM_METHOD', 'is not set')] # refers to LOCKDOWN
552 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_BRK', 'is not set')]
553 l += [KconfigCheck('cut_attack_surface', 'kspp', 'DEVKMEM', 'is not set')] # refers to LOCKDOWN
554 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_VDSO', 'is not set')]
555 l += [KconfigCheck('cut_attack_surface', 'kspp', 'BINFMT_MISC', 'is not set')]
556 l += [KconfigCheck('cut_attack_surface', 'kspp', 'INET_DIAG', 'is not set')]
557 l += [KconfigCheck('cut_attack_surface', 'kspp', 'KEXEC', 'is not set')] # refers to LOCKDOWN
558 l += [KconfigCheck('cut_attack_surface', 'kspp', 'PROC_KCORE', 'is not set')] # refers to LOCKDOWN
559 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_PTYS', 'is not set')]
560 l += [KconfigCheck('cut_attack_surface', 'kspp', 'HIBERNATION', 'is not set')] # refers to LOCKDOWN
561 l += [KconfigCheck('cut_attack_surface', 'kspp', 'IA32_EMULATION', 'is not set')]
562 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_X32', 'is not set')]
563 l += [KconfigCheck('cut_attack_surface', 'kspp', 'MODIFY_LDT_SYSCALL', 'is not set')]
564 l += [KconfigCheck('cut_attack_surface', 'kspp', 'OABI_COMPAT', 'is not set')]
565 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_MSR', 'is not set')] # refers to LOCKDOWN
566 l += [modules_not_set]
567 l += [devmem_not_set]
568 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'IO_STRICT_DEVMEM', 'y'),
569 devmem_not_set)] # refers to LOCKDOWN
571 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'STRICT_DEVMEM', 'y'),
572 devmem_not_set)] # refers to LOCKDOWN
574 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y')] # 'vsyscall=none'
576 # 'cut_attack_surface', 'grsec'
577 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ZSMALLOC_STAT', 'is not set')]
578 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PAGE_OWNER', 'is not set')]
579 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_KMEMLEAK', 'is not set')]
580 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BINFMT_AOUT', 'is not set')]
581 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KPROBE_EVENTS', 'is not set')]
582 l += [KconfigCheck('cut_attack_surface', 'grsec', 'UPROBE_EVENTS', 'is not set')]
583 l += [KconfigCheck('cut_attack_surface', 'grsec', 'GENERIC_TRACER', 'is not set')] # refers to LOCKDOWN
584 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FUNCTION_TRACER', 'is not set')]
585 l += [KconfigCheck('cut_attack_surface', 'grsec', 'STACK_TRACER', 'is not set')]
586 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HIST_TRIGGERS', 'is not set')]
587 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BLK_DEV_IO_TRACE', 'is not set')]
588 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_VMCORE', 'is not set')]
589 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_PAGE_MONITOR', 'is not set')]
590 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USELIB', 'is not set')]
591 l += [KconfigCheck('cut_attack_surface', 'grsec', 'CHECKPOINT_RESTORE', 'is not set')]
592 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USERFAULTFD', 'is not set')]
593 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HWPOISON_INJECT', 'is not set')]
594 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MEM_SOFT_DIRTY', 'is not set')]
595 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEVPORT', 'is not set')] # refers to LOCKDOWN
596 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set')] # refers to LOCKDOWN
597 l += [KconfigCheck('cut_attack_surface', 'grsec', 'NOTIFIER_ERROR_INJECTION', 'is not set')]
598 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FAIL_FUTEX', 'is not set')]
599 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PUNIT_ATOM_DEBUG', 'is not set')]
600 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ACPI_CONFIGFS', 'is not set')]
601 l += [KconfigCheck('cut_attack_surface', 'grsec', 'EDAC_DEBUG', 'is not set')]
602 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DRM_I915_DEBUG', 'is not set')]
603 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BCACHE_CLOSURES_DEBUG', 'is not set')]
604 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DVB_C8SECTPFE', 'is not set')]
605 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_SLRAM', 'is not set')]
606 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_PHRAM', 'is not set')]
607 l += [KconfigCheck('cut_attack_surface', 'grsec', 'IO_URING', 'is not set')]
608 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCMP', 'is not set')]
609 l += [KconfigCheck('cut_attack_surface', 'grsec', 'RSEQ', 'is not set')]
610 l += [KconfigCheck('cut_attack_surface', 'grsec', 'LATENCYTOP', 'is not set')]
611 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCOV', 'is not set')]
612 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROVIDE_OHCI1394_DMA_INIT', 'is not set')]
613 l += [KconfigCheck('cut_attack_surface', 'grsec', 'SUNRPC_DEBUG', 'is not set')]
614 l += [AND(KconfigCheck('cut_attack_surface', 'grsec', 'PTDUMP_DEBUGFS', 'is not set'),
615 KconfigCheck('cut_attack_surface', 'grsec', 'X86_PTDUMP', 'is not set'))]
617 # 'cut_attack_surface', 'maintainer'
618 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'DRM_LEGACY', 'is not set')] # recommended by Daniel Vetter in /issues/38
619 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'FB', 'is not set')] # recommended by Daniel Vetter in /issues/38
620 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'VT', 'is not set')] # recommended by Daniel Vetter in /issues/38
621 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD', 'is not set')] # recommended by Denis Efremov in /pull/54
622 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD_RAWCMD', 'is not set')] # recommended by Denis Efremov in /pull/62
624 # 'cut_attack_surface', 'grapheneos'
625 l += [KconfigCheck('cut_attack_surface', 'grapheneos', 'AIO', 'is not set')]
627 # 'cut_attack_surface', 'clipos'
628 l += [KconfigCheck('cut_attack_surface', 'clipos', 'STAGING', 'is not set')]
629 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KSM', 'is not set')] # to prevent FLUSH+RELOAD attack
630 # l += [KconfigCheck('cut_attack_surface', 'clipos', 'IKCONFIG', 'is not set')] # no, IKCONFIG is needed for this check :)
631 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KALLSYMS', 'is not set')]
632 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_VSYSCALL_EMULATION', 'is not set')]
633 l += [KconfigCheck('cut_attack_surface', 'clipos', 'MAGIC_SYSRQ', 'is not set')]
634 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KEXEC_FILE', 'is not set')] # refers to LOCKDOWN (permissive)
635 l += [KconfigCheck('cut_attack_surface', 'clipos', 'USER_NS', 'is not set')] # user.max_user_namespaces=0
636 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_CPUID', 'is not set')]
637 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_IOPL_IOPERM', 'is not set')] # refers to LOCKDOWN
638 l += [KconfigCheck('cut_attack_surface', 'clipos', 'ACPI_TABLE_UPGRADE', 'is not set')] # refers to LOCKDOWN
639 l += [KconfigCheck('cut_attack_surface', 'clipos', 'EFI_CUSTOM_SSDT_OVERLAYS', 'is not set')]
640 l += [AND(KconfigCheck('cut_attack_surface', 'clipos', 'LDISC_AUTOLOAD', 'is not set'),
641 KconfigCheck('cut_attack_surface', 'clipos', 'LDISC_AUTOLOAD'))] # option presence check
642 if arch in ('X86_64', 'X86_32'):
643 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_INTEL_TSX_MODE_OFF', 'y')] # tsx=off
645 # 'cut_attack_surface', 'lockdown'
646 l += [bpf_syscall_not_set] # refers to LOCKDOWN
647 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'EFI_TEST', 'is not set')] # refers to LOCKDOWN
648 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'MMIOTRACE_TEST', 'is not set')] # refers to LOCKDOWN
649 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'KPROBES', 'is not set')] # refers to LOCKDOWN
651 # 'cut_attack_surface', 'my'
652 l += [OR(KconfigCheck('cut_attack_surface', 'my', 'TRIM_UNUSED_KSYMS', 'y'),
654 l += [KconfigCheck('cut_attack_surface', 'my', 'MMIOTRACE', 'is not set')] # refers to LOCKDOWN (permissive)
655 l += [KconfigCheck('cut_attack_surface', 'my', 'LIVEPATCH', 'is not set')]
656 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_DCCP', 'is not set')]
657 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_SCTP', 'is not set')]
658 l += [KconfigCheck('cut_attack_surface', 'my', 'FTRACE', 'is not set')] # refers to LOCKDOWN
659 l += [KconfigCheck('cut_attack_surface', 'my', 'VIDEO_VIVID', 'is not set')]
660 l += [KconfigCheck('cut_attack_surface', 'my', 'INPUT_EVBUG', 'is not set')] # Can be used as a keylogger
661 l += [KconfigCheck('cut_attack_surface', 'my', 'KGDB', 'is not set')]
664 if arch in ('X86_64', 'ARM64', 'X86_32'):
665 l += [KconfigCheck('harden_userspace', 'defconfig', 'INTEGRITY', 'y')]
667 l += [KconfigCheck('harden_userspace', 'my', 'INTEGRITY', 'y')]
669 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_PTR_AUTH', 'y')]
670 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_BTI', 'y')]
671 if arch in ('ARM', 'X86_32'):
672 l += [KconfigCheck('harden_userspace', 'defconfig', 'VMSPLIT_3G', 'y')]
673 if arch in ('X86_64', 'ARM64'):
674 l += [KconfigCheck('harden_userspace', 'clipos', 'ARCH_MMAP_RND_BITS', '32')]
675 if arch in ('X86_32', 'ARM'):
676 l += [KconfigCheck('harden_userspace', 'my', 'ARCH_MMAP_RND_BITS', '16')]
679 def add_cmdline_checks(l, arch):
680 # Calling the CmdlineCheck class constructor:
681 # CmdlineCheck(reason, decision, name, expected)
683 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
684 # when the tool doesn't check the cmdline.
686 # [!] Make sure that values of the options in CmdlineChecks need normalization.
687 # For more info see normalize_cmdline_options().
689 # A common pattern for checking the 'param_x' cmdline parameter
690 # that __overrides__ the 'PARAM_X_DEFAULT' kconfig option:
691 # l += [OR(CmdlineCheck(reason, decision, 'param_x', '1'),
692 # AND(KconfigCheck(reason, decision, 'PARAM_X_DEFAULT_ON', 'y'),
693 # CmdlineCheck(reason, decision, 'param_x, 'is not set')))]
695 # Here we don't check the kconfig options or minimal kernel version
696 # required for the cmdline parameters. That would make the checks
697 # very complex and not give a 100% guarantee anyway.
699 # 'self_protection', 'defconfig'
700 l += [CmdlineCheck('self_protection', 'defconfig', 'nosmep', 'is not set')]
701 l += [CmdlineCheck('self_protection', 'defconfig', 'nosmap', 'is not set')]
702 l += [CmdlineCheck('self_protection', 'defconfig', 'nokaslr', 'is not set')]
703 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v1', 'is not set')]
704 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v2', 'is not set')]
706 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', 'full'),
707 AND(KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y'),
708 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set')))]
710 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', '1'),
711 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set'))]
713 # 'self_protection', 'kspp'
714 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', '1'),
715 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y'),
716 CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', 'is not set')))]
717 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_free', '1'),
718 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
719 CmdlineCheck('self_protection', 'kspp', 'init_on_free', 'is not set')),
720 AND(CmdlineCheck('self_protection', 'kspp', 'page_poison', '1'),
721 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'),
722 CmdlineCheck('self_protection', 'kspp', 'slub_debug', 'P')))]
723 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_nomerge'),
724 AND(KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set'),
725 CmdlineCheck('self_protection', 'kspp', 'slab_merge', 'is not set')))] # option presence check
726 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.strict', '1'),
727 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y'),
728 CmdlineCheck('self_protection', 'kspp', 'iommu.strict', 'is not set')))]
729 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', '0'),
730 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set'),
731 CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', 'is not set')))]
732 # The cmdline checks compatible with the kconfig recommendations of the KSPP project...
733 l += [OR(CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', '1'),
734 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y'),
735 CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', 'is not set')))]
736 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', '0'),
737 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
738 CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', 'is not set')))]
739 if arch in ('X86_64', 'X86_32'):
740 l += [AND(CmdlineCheck('self_protection', 'kspp', 'pti', 'on'),
741 CmdlineCheck('self_protection', 'kspp', 'nopti', 'is not set'))] # ... the end
742 if arch in ('X86_64', 'ARM64', 'X86_32'):
743 l += [OR(CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', '1'),
744 AND(KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y'),
745 CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', 'is not set')))]
747 # 'self_protection', 'clipos'
748 l += [CmdlineCheck('self_protection', 'clipos', 'page_alloc.shuffle', '1')]
749 if arch in ('X86_64', 'X86_32'):
750 l += [CmdlineCheck('self_protection', 'clipos', 'spectre_v2', 'on')]
752 # 'cut_attack_surface', 'kspp'
754 l += [OR(CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'none'),
755 AND(KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y'),
756 CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'is not set')))]
758 # 'cut_attack_surface', 'grsec'
759 # The cmdline checks compatible with the kconfig options disabled by grsecurity...
760 l += [OR(CmdlineCheck('cut_attack_surface', 'grsec', 'debugfs', 'off'),
761 KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set'))] # ... the end
764 def print_unknown_options(checklist, parsed_options):
768 if o1.type != 'complex':
769 known_options.append(o1.name)
772 if o2.type != 'complex':
773 if hasattr(o2, 'name'):
774 known_options.append(o2.name)
777 assert(o3.type != 'complex'), \
778 'unexpected ComplexOptCheck inside {}'.format(o2.name)
779 if hasattr(o3, 'name'):
780 known_options.append(o3.name)
782 for option, value in parsed_options.items():
783 if option not in known_options:
784 print('[?] No check for option {} ({})'.format(option, value))
787 def print_checklist(mode, checklist, with_results):
791 output.append(o.json_dump(with_results))
792 print(json.dumps(output))
799 print('=' * sep_line_len)
800 print('{:^40}|{:^7}|{:^12}|{:^10}|{:^18}'.format('option name', 'type', 'desired val', 'decision', 'reason'), end='')
802 print('| {}'.format('check result'), end='')
804 print('=' * sep_line_len)
807 for opt in checklist:
809 if mode == 'show_ok':
810 if not opt.result.startswith('OK'):
812 if mode == 'show_fail':
813 if not opt.result.startswith('FAIL'):
815 opt.table_print(mode, with_results)
817 if mode == 'verbose':
818 print('-' * sep_line_len)
823 fail_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), checklist)))
825 ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), checklist)))
827 if mode == 'show_ok':
828 fail_suppressed = ' (suppressed in output)'
829 if mode == 'show_fail':
830 ok_suppressed = ' (suppressed in output)'
832 print('[+] Config check is finished: \'OK\' - {}{} / \'FAIL\' - {}{}'.format(ok_count, ok_suppressed, fail_count, fail_suppressed))
835 def populate_simple_opt_with_data(opt, data, data_type):
836 assert(opt.type != 'complex'), \
837 'unexpected ComplexOptCheck "{}"'.format(opt.name)
838 assert(opt.type in SIMPLE_OPTION_TYPES), \
839 'invalid opt type "{}"'.format(opt.type)
840 assert(data_type in SIMPLE_OPTION_TYPES), \
841 'invalid data type "{}"'.format(data_type)
843 if data_type != opt.type:
846 if data_type in ('kconfig', 'cmdline'):
847 opt.state = data.get(opt.name, None)
849 assert(data_type == 'version'), \
850 'unexpected data type "{}"'.format(data_type)
854 def populate_opt_with_data(opt, data, data_type):
855 if opt.type == 'complex':
857 if o.type == 'complex':
858 # Recursion for nested ComplexOptCheck objects
859 populate_opt_with_data(o, data, data_type)
861 populate_simple_opt_with_data(o, data, data_type)
863 assert(opt.type in ('kconfig', 'cmdline')), \
864 'bad type "{}" for a simple check'.format(opt.type)
865 populate_simple_opt_with_data(opt, data, data_type)
868 def populate_with_data(checklist, data, data_type):
869 for opt in checklist:
870 populate_opt_with_data(opt, data, data_type)
873 def perform_checks(checklist):
874 for opt in checklist:
878 def parse_kconfig_file(parsed_options, fname):
879 with open(fname, 'r') as f:
880 opt_is_on = re.compile("CONFIG_[a-zA-Z0-9_]*=[a-zA-Z0-9_\"]*")
881 opt_is_off = re.compile("# CONFIG_[a-zA-Z0-9_]* is not set")
883 for line in f.readlines():
888 if opt_is_on.match(line):
889 option, value = line.split('=', 1)
890 if value == 'is not set':
891 sys.exit('[!] ERROR: bad enabled kconfig option "{}"'.format(line))
892 elif opt_is_off.match(line):
893 option, value = line[2:].split(' ', 1)
894 if value != 'is not set':
895 sys.exit('[!] ERROR: bad disabled kconfig option "{}"'.format(line))
897 if option in parsed_options:
898 sys.exit('[!] ERROR: kconfig option "{}" exists multiple times'.format(line))
901 parsed_options[option] = value
904 def normalize_cmdline_options(option, value):
905 # Don't normalize the cmdline option values if
906 # the Linux kernel doesn't use kstrtobool() for them
908 # See pti_check_boottime_disable() in linux/arch/x86/mm/pti.c
910 if option == 'spectre_v2':
911 # See spectre_v2_parse_cmdline() in linux/arch/x86/kernel/cpu/bugs.c
913 if option == 'debugfs':
914 # See debugfs_kernel() in fs/debugfs/inode.c
917 # Implement a limited part of the kstrtobool() logic
918 if value in ('1', 'on', 'On', 'ON', 'y', 'Y', 'yes', 'Yes', 'YES'):
920 if value in ('0', 'off', 'Off', 'OFF', 'n', 'N', 'no', 'No', 'NO'):
923 # Preserve unique values
927 def parse_cmdline_file(parsed_options, fname):
928 with open(fname, 'r') as f:
934 sys.exit('[!] ERROR: more than one line in "{}"'.format(fname))
938 name, value = opt.split('=', 1)
941 value = '' # '' is not None
942 value = normalize_cmdline_options(name, value)
943 parsed_options[name] = value
949 # - reporting about unknown kernel options in the kconfig
950 # - verbose printing of ComplexOptCheck items
951 # * json mode for printing the results in JSON format
952 report_modes = ['verbose', 'json', 'show_ok', 'show_fail']
953 supported_archs = ['X86_64', 'X86_32', 'ARM64', 'ARM']
954 parser = ArgumentParser(prog='kconfig-hardened-check',
955 description='A tool for checking the security hardening options of the Linux kernel')
956 parser.add_argument('--version', action='version', version='%(prog)s ' + __version__)
957 parser.add_argument('-p', '--print', choices=supported_archs,
958 help='print security hardening preferences for the selected architecture')
959 parser.add_argument('-c', '--config',
960 help='check the kernel kconfig file against these preferences')
961 parser.add_argument('-l', '--cmdline',
962 help='check the kernel cmdline file against these preferences')
963 parser.add_argument('-m', '--mode', choices=report_modes,
964 help='choose the report mode')
965 args = parser.parse_args()
971 print('[+] Special report mode: {}'.format(mode))
973 config_checklist = []
977 sys.exit('[!] ERROR: --config and --print can\'t be used together')
980 print('[+] Kconfig file to check: {}'.format(args.config))
982 print('[+] Kernel cmdline file to check: {}'.format(args.cmdline))
984 arch, msg = detect_arch(args.config, supported_archs)
986 sys.exit('[!] ERROR: {}'.format(msg))
988 print('[+] Detected architecture: {}'.format(arch))
990 kernel_version, msg = detect_kernel_version(args.config)
991 if not kernel_version:
992 sys.exit('[!] ERROR: {}'.format(msg))
994 print('[+] Detected kernel version: {}.{}'.format(kernel_version[0], kernel_version[1]))
996 compiler, msg = detect_compiler(args.config)
999 print('[+] Detected compiler: {}'.format(compiler))
1001 print('[-] Can\'t detect the compiler: {}'.format(msg))
1003 # add relevant kconfig checks to the checklist
1004 add_kconfig_checks(config_checklist, arch)
1007 # add relevant cmdline checks to the checklist
1008 add_cmdline_checks(config_checklist, arch)
1010 # populate the checklist with the parsed kconfig data
1011 parsed_kconfig_options = OrderedDict()
1012 parse_kconfig_file(parsed_kconfig_options, args.config)
1013 populate_with_data(config_checklist, parsed_kconfig_options, 'kconfig')
1014 populate_with_data(config_checklist, kernel_version, 'version')
1017 # populate the checklist with the parsed kconfig data
1018 parsed_cmdline_options = OrderedDict()
1019 parse_cmdline_file(parsed_cmdline_options, args.cmdline)
1020 populate_with_data(config_checklist, parsed_cmdline_options, 'cmdline')
1022 # now everything is ready for performing the checks
1023 perform_checks(config_checklist)
1025 # finally print the results
1026 if mode == 'verbose':
1027 print_unknown_options(config_checklist, parsed_kconfig_options)
1028 print_checklist(mode, config_checklist, True)
1032 sys.exit('[!] ERROR: checking cmdline doesn\'t work without checking kconfig')
1035 if mode in ('show_ok', 'show_fail'):
1036 sys.exit('[!] ERROR: wrong mode "{}" for --print'.format(mode))
1038 add_kconfig_checks(config_checklist, arch)
1039 add_cmdline_checks(config_checklist, arch)
1041 print('[+] Printing kernel security hardening preferences for {}...'.format(arch))
1042 print_checklist(mode, config_checklist, False)