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?)
15 # slub_debug=FZ (slow)
17 # debugfs=no-mount (or off if possible)
19 # Mitigations of CPU vulnerabilities:
21 # mitigations=auto,nosmt (nosmt is slow)
24 # spec_store_bypass_disable=on
26 # l1d_flush=on (a part of the l1tf option)
35 # sysrq_always_enabled
40 # Hardware tag-based KASAN with arm64 Memory Tagging Extension (MTE):
42 # kasan.stacktrace=off
45 # N.B. Hardening sysctls:
46 # kernel.kptr_restrict=2 (or 1?)
47 # kernel.dmesg_restrict=1 (also see the kconfig option)
48 # kernel.perf_event_paranoid=3
49 # kernel.kexec_load_disabled=1
50 # kernel.yama.ptrace_scope=3
51 # user.max_user_namespaces=0
52 # what about bpf_jit_enable?
53 # kernel.unprivileged_bpf_disabled=1
54 # net.core.bpf_jit_harden=2
55 # vm.unprivileged_userfaultfd=0
56 # (at first, it disabled unprivileged userfaultfd,
57 # and since v5.11 it enables unprivileged userfaultfd for user-mode only)
58 # vm.mmap_min_addr has a good value
59 # dev.tty.ldisc_autoload=0
60 # fs.protected_symlinks=1
61 # fs.protected_hardlinks=1
62 # fs.protected_fifos=2
63 # fs.protected_regular=2
65 # kernel.modules_disabled=1
66 # kernel.randomize_va_space = 2
69 # pylint: disable=missing-module-docstring,missing-class-docstring,missing-function-docstring
70 # pylint: disable=line-too-long,invalid-name,too-many-branches,too-many-statements
74 from argparse import ArgumentParser
75 from collections import OrderedDict
78 from .__about__ import __version__
80 SIMPLE_OPTION_TYPES = ('kconfig', 'version', 'cmdline')
83 # Constructor without the 'expected' parameter is for option presence checks (any value is OK)
84 def __init__(self, reason, decision, name, expected=None):
85 assert(reason and decision and name), \
86 'invalid {} check for "{}"'.format(self.__class__.__name__, name)
88 self.expected = expected
89 self.decision = decision
99 # handle the option presence check
100 if self.expected is None:
101 if self.state is None:
102 self.result = 'FAIL: not present'
104 self.result = 'OK: is present'
107 # handle the option value check
108 if self.expected == self.state:
110 elif self.state is None:
111 if self.expected == 'is not set':
112 self.result = 'OK: not found'
114 self.result = 'FAIL: not found'
116 self.result = 'FAIL: "' + self.state + '"'
118 def table_print(self, _mode, with_results):
119 if self.expected is None:
122 expected = self.expected
123 print('{:<40}|{:^7}|{:^12}|{:^10}|{:^18}'.format(self.name, self.type, expected, self.decision, self.reason), end='')
125 print('| {}'.format(self.result), end='')
127 def json_dump(self, with_results):
128 dump = [self.name, self.type, self.expected, self.decision, self.reason]
130 dump.append(self.result)
134 class KconfigCheck(OptCheck):
135 def __init__(self, *args, **kwargs):
136 super().__init__(*args, **kwargs)
137 self.name = 'CONFIG_' + self.name
144 class CmdlineCheck(OptCheck):
151 def __init__(self, ver_expected):
152 self.ver_expected = ver_expected
161 if self.ver[0] > self.ver_expected[0]:
162 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
164 if self.ver[0] < self.ver_expected[0]:
165 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
167 if self.ver[1] >= self.ver_expected[1]:
168 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
170 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
172 def table_print(self, _mode, with_results):
173 ver_req = 'kernel version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
174 print('{:<91}'.format(ver_req), end='')
176 print('| {}'.format(self.result), end='')
179 class ComplexOptCheck:
180 def __init__(self, *opts):
183 'empty {} check'.format(self.__class__.__name__)
184 assert(len(self.opts) != 1), \
185 'useless {} check: {}'.format(self.__class__.__name__, opts)
186 assert(isinstance(opts[0], (KconfigCheck, CmdlineCheck))), \
187 'invalid {} check: {}'.format(self.__class__.__name__, opts)
196 return self.opts[0].name
200 return self.opts[0].expected
202 def table_print(self, mode, with_results):
203 if mode == 'verbose':
204 print(' {:87}'.format('<<< ' + self.__class__.__name__ + ' >>>'), end='')
206 print('| {}'.format(self.result), end='')
209 o.table_print(mode, with_results)
212 o.table_print(mode, False)
214 print('| {}'.format(self.result), end='')
216 def json_dump(self, with_results):
217 dump = self.opts[0].json_dump(False)
219 dump.append(self.result)
223 class OR(ComplexOptCheck):
224 # self.opts[0] is the option that this OR-check is about.
226 # OR(<X_is_hardened>, <X_is_disabled>)
227 # OR(<X_is_hardened>, <old_X_is_hardened>)
229 for i, opt in enumerate(self.opts):
231 if opt.result.startswith('OK'):
232 self.result = opt.result
233 # Add more info for additional checks:
235 if opt.result == 'OK':
236 self.result = 'OK: {} "{}"'.format(opt.name, opt.expected)
237 elif opt.result == 'OK: not found':
238 self.result = 'OK: {} not found'.format(opt.name)
239 elif opt.result == 'OK: is present':
240 self.result = 'OK: {} is present'.format(opt.name)
242 # VersionCheck provides enough info
243 assert(opt.result.startswith('OK: version')), \
244 'unexpected OK description "{}"'.format(opt.result)
246 self.result = self.opts[0].result
249 class AND(ComplexOptCheck):
250 # self.opts[0] is the option that this AND-check is about.
252 # AND(<suboption>, <main_option>)
253 # Suboption is not checked if checking of the main_option is failed.
254 # AND(<X_is_disabled>, <old_X_is_disabled>)
256 for i, opt in reversed(list(enumerate(self.opts))):
259 self.result = opt.result
261 if not opt.result.startswith('OK'):
262 # This FAIL is caused by additional checks,
263 # and not by the main option that this AND-check is about.
264 # Describe the reason of the FAIL.
265 if opt.result.startswith('FAIL: \"') or opt.result == 'FAIL: not found':
266 self.result = 'FAIL: {} not "{}"'.format(opt.name, opt.expected)
267 elif opt.result == 'FAIL: not present':
268 self.result = 'FAIL: {} not present'.format(opt.name)
270 # VersionCheck provides enough info
271 self.result = opt.result
272 assert(opt.result.startswith('FAIL: version')), \
273 'unexpected FAIL description "{}"'.format(opt.result)
277 def detect_arch(fname, archs):
278 with open(fname, 'r') as f:
279 arch_pattern = re.compile("CONFIG_[a-zA-Z0-9_]*=y")
281 for line in f.readlines():
282 if arch_pattern.match(line):
283 option, _ = line[7:].split('=', 1)
288 return None, 'more than one supported architecture is detected'
290 return None, 'failed to detect architecture'
294 def detect_version(fname):
295 with open(fname, 'r') as f:
296 ver_pattern = re.compile("# Linux/.* Kernel Configuration")
297 for line in f.readlines():
298 if ver_pattern.match(line):
302 ver_numbers = ver_str.split('.')
303 if len(ver_numbers) < 3 or not ver_numbers[0].isdigit() or not ver_numbers[1].isdigit():
304 msg = 'failed to parse the version "' + ver_str + '"'
306 return (int(ver_numbers[0]), int(ver_numbers[1])), None
307 return None, 'no kernel version detected'
310 def add_kconfig_checks(l, arch):
311 # Calling the KconfigCheck class constructor:
312 # KconfigCheck(reason, decision, name, expected)
314 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
315 # when the tool doesn't check the cmdline.
317 modules_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'MODULES', 'is not set')
318 devmem_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'DEVMEM', 'is not set') # refers to LOCKDOWN
319 bpf_syscall_not_set = KconfigCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set') # refers to LOCKDOWN
320 efi_not_set = KconfigCheck('cut_attack_surface', 'my', 'EFI', 'is not set')
322 # 'self_protection', 'defconfig'
323 l += [KconfigCheck('self_protection', 'defconfig', 'BUG', 'y')]
324 l += [KconfigCheck('self_protection', 'defconfig', 'SLUB_DEBUG', 'y')]
325 l += [KconfigCheck('self_protection', 'defconfig', 'GCC_PLUGINS', 'y')]
326 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR', 'y'),
327 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR', 'y'),
328 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_REGULAR', 'y'),
329 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_AUTO', 'y'),
330 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
331 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_STRONG', 'y'),
332 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
333 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_KERNEL_RWX', 'y'),
334 KconfigCheck('self_protection', 'defconfig', 'DEBUG_RODATA', 'y'))] # before v4.11
335 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_MODULE_RWX', 'y'),
336 KconfigCheck('self_protection', 'defconfig', 'DEBUG_SET_MODULE_RONX', 'y'),
337 modules_not_set)] # DEBUG_SET_MODULE_RONX was before v4.11
338 l += [OR(KconfigCheck('self_protection', 'defconfig', 'REFCOUNT_FULL', 'y'),
339 VersionCheck((5, 5)))] # REFCOUNT_FULL is enabled by default since v5.5
340 l += [KconfigCheck('self_protection', 'defconfig', 'THREAD_INFO_IN_TASK', 'y')]
341 iommu_support_is_set = KconfigCheck('self_protection', 'defconfig', 'IOMMU_SUPPORT', 'y')
342 l += [iommu_support_is_set] # is needed for mitigating DMA attacks
343 if arch in ('X86_64', 'ARM64', 'X86_32'):
344 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y')]
345 if arch in ('X86_64', 'ARM64'):
346 l += [KconfigCheck('self_protection', 'defconfig', 'VMAP_STACK', 'y')]
347 if arch in ('X86_64', 'X86_32'):
348 l += [KconfigCheck('self_protection', 'defconfig', 'MICROCODE', 'y')] # is needed for mitigating CPU bugs
349 l += [KconfigCheck('self_protection', 'defconfig', 'RETPOLINE', 'y')]
350 l += [KconfigCheck('self_protection', 'defconfig', 'X86_SMAP', 'y')]
351 l += [KconfigCheck('self_protection', 'defconfig', 'SYN_COOKIES', 'y')] # another reason?
352 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_UMIP', 'y'),
353 KconfigCheck('self_protection', 'defconfig', 'X86_INTEL_UMIP', 'y'))]
354 if arch in ('ARM64', 'ARM'):
355 l += [KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_PER_TASK', 'y')]
357 l += [KconfigCheck('self_protection', 'defconfig', 'PAGE_TABLE_ISOLATION', 'y')]
358 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MEMORY', 'y')]
359 l += [AND(KconfigCheck('self_protection', 'defconfig', 'INTEL_IOMMU', 'y'),
360 iommu_support_is_set)]
361 l += [AND(KconfigCheck('self_protection', 'defconfig', 'AMD_IOMMU', 'y'),
362 iommu_support_is_set)]
364 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PAN', 'y')]
365 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_EPAN', 'y')]
366 l += [KconfigCheck('self_protection', 'defconfig', 'UNMAP_KERNEL_AT_EL0', 'y')]
367 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_EL2_VECTORS', 'y'),
368 AND(KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y'),
369 VersionCheck((5, 9))))] # HARDEN_EL2_VECTORS was included in RANDOMIZE_BASE in v5.9
370 l += [KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y')]
371 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PTR_AUTH_KERNEL', 'y')]
372 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_BTI_KERNEL', 'y')]
373 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y'),
374 VersionCheck((5, 10)))] # HARDEN_BRANCH_PREDICTOR is enabled by default since v5.10
375 l += [KconfigCheck('self_protection', 'defconfig', 'MITIGATE_SPECTRE_BRANCH_HISTORY', 'y')]
376 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_MTE', 'y')]
377 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MODULE_REGION_FULL', 'y')]
379 l += [KconfigCheck('self_protection', 'defconfig', 'CPU_SW_DOMAIN_PAN', 'y')]
380 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y')]
381 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_HISTORY', 'y')]
383 # 'self_protection', 'kspp'
384 l += [KconfigCheck('self_protection', 'kspp', 'BUG_ON_DATA_CORRUPTION', 'y')]
385 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_WX', 'y')]
386 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_STACK_END_CHECK', 'y')]
387 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_HARDENED', 'y')]
388 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_RANDOM', 'y')]
389 l += [KconfigCheck('self_protection', 'kspp', 'SHUFFLE_PAGE_ALLOCATOR', 'y')]
390 l += [KconfigCheck('self_protection', 'kspp', 'FORTIFY_SOURCE', 'y')]
391 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_LIST', 'y')]
392 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_SG', 'y')]
393 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_CREDENTIALS', 'y')]
394 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_NOTIFIERS', 'y')]
395 l += [KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y')]
396 l += [KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_LATENT_ENTROPY', 'y')]
397 l += [KconfigCheck('self_protection', 'kspp', 'KFENCE', 'y')]
398 l += [KconfigCheck('self_protection', 'kspp', 'WERROR', 'y')]
399 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y')]
400 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set')] # true if IOMMU_DEFAULT_DMA_STRICT is set
401 l += [KconfigCheck('self_protection', 'kspp', 'ZERO_CALL_USED_REGS', 'y')]
402 randstruct_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT', 'y')
403 l += [randstruct_is_set]
404 hardened_usercopy_is_set = KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y')
405 l += [hardened_usercopy_is_set]
406 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
407 hardened_usercopy_is_set)]
408 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_PAGESPAN', 'is not set'),
409 hardened_usercopy_is_set)]
410 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG', 'y'),
412 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_ALL', 'y'),
414 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_SHA512', 'y'),
416 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_FORCE', 'y'),
417 modules_not_set)] # refers to LOCKDOWN
418 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_STACK_ALL_ZERO', 'y'),
419 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y'))]
420 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
421 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'))]
422 # CONFIG_INIT_ON_FREE_DEFAULT_ON was added in v5.3.
423 # CONFIG_PAGE_POISONING_ZERO was removed in v5.11.
424 # Starting from v5.11 CONFIG_PAGE_POISONING unconditionally checks
425 # the 0xAA poison pattern on allocation.
426 # That brings higher performance penalty.
427 if arch in ('X86_64', 'ARM64', 'X86_32'):
428 stackleak_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STACKLEAK', 'y')
429 l += [stackleak_is_set]
430 l += [KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y')]
431 if arch in ('X86_64', 'X86_32'):
432 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_CORE', 'y')]
433 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '65536')]
434 if arch in ('ARM64', 'ARM'):
435 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '32768')]
436 l += [KconfigCheck('self_protection', 'kspp', 'SYN_COOKIES', 'y')] # another reason?
438 l += [KconfigCheck('self_protection', 'kspp', 'ARM64_SW_TTBR0_PAN', 'y')]
440 l += [KconfigCheck('self_protection', 'kspp', 'PAGE_TABLE_ISOLATION', 'y')]
441 l += [KconfigCheck('self_protection', 'kspp', 'HIGHMEM64G', 'y')]
442 l += [KconfigCheck('self_protection', 'kspp', 'X86_PAE', 'y')]
444 # 'self_protection', 'maintainer'
445 ubsan_bounds_is_set = KconfigCheck('self_protection', 'maintainer', 'UBSAN_BOUNDS', 'y') # only array index bounds checking
446 l += [ubsan_bounds_is_set] # recommended by Kees Cook in /issues/53
447 if arch in ('X86_64', 'ARM64', 'X86_32'): # ARCH_HAS_UBSAN_SANITIZE_ALL is not enabled for ARM
448 l += [AND(KconfigCheck('self_protection', 'maintainer', 'UBSAN_SANITIZE_ALL', 'y'),
449 ubsan_bounds_is_set)] # recommended by Kees Cook in /issues/53
450 l += [AND(KconfigCheck('self_protection', 'maintainer', 'UBSAN_TRAP', 'y'),
451 ubsan_bounds_is_set)] # recommended by Kees Cook in /issues/53
453 # 'self_protection', 'clipos'
454 l += [KconfigCheck('self_protection', 'clipos', 'DEBUG_VIRTUAL', 'y')]
455 l += [KconfigCheck('self_protection', 'clipos', 'STATIC_USERMODEHELPER', 'y')] # needs userspace support
456 l += [OR(KconfigCheck('self_protection', 'clipos', 'EFI_DISABLE_PCI_DMA', 'y'),
458 l += [KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set')]
459 l += [KconfigCheck('self_protection', 'clipos', 'RANDOM_TRUST_BOOTLOADER', 'is not set')]
460 l += [KconfigCheck('self_protection', 'clipos', 'RANDOM_TRUST_CPU', 'is not set')]
461 l += [AND(KconfigCheck('self_protection', 'clipos', 'GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set'),
463 if arch in ('X86_64', 'ARM64', 'X86_32'):
464 l += [AND(KconfigCheck('self_protection', 'clipos', 'STACKLEAK_METRICS', 'is not set'),
466 l += [AND(KconfigCheck('self_protection', 'clipos', 'STACKLEAK_RUNTIME_DISABLE', 'is not set'),
468 if arch in ('X86_64', 'X86_32'):
469 l += [AND(KconfigCheck('self_protection', 'clipos', 'INTEL_IOMMU_DEFAULT_ON', 'y'),
470 iommu_support_is_set)]
472 l += [AND(KconfigCheck('self_protection', 'clipos', 'INTEL_IOMMU_SVM', 'y'),
473 iommu_support_is_set)]
475 l += [AND(KconfigCheck('self_protection', 'clipos', 'INTEL_IOMMU', 'y'),
476 iommu_support_is_set)]
478 # 'self_protection', 'my'
479 l += [OR(KconfigCheck('self_protection', 'my', 'RESET_ATTACK_MITIGATION', 'y'),
480 efi_not_set)] # needs userspace support (systemd)
482 l += [KconfigCheck('self_protection', 'my', 'SLS', 'y')] # vs CVE-2021-26341 in Straight-Line-Speculation
483 l += [AND(KconfigCheck('self_protection', 'my', 'AMD_IOMMU_V2', 'y'),
484 iommu_support_is_set)]
486 l += [KconfigCheck('self_protection', 'my', 'SHADOW_CALL_STACK', 'y')] # depends on clang, maybe it's alternative to STACKPROTECTOR_STRONG
487 l += [KconfigCheck('self_protection', 'my', 'KASAN_HW_TAGS', 'y')]
488 cfi_clang_is_set = KconfigCheck('self_protection', 'my', 'CFI_CLANG', 'y')
489 l += [cfi_clang_is_set]
490 l += [AND(KconfigCheck('self_protection', 'my', 'CFI_PERMISSIVE', 'is not set'),
494 if arch in ('X86_64', 'ARM64', 'X86_32'):
495 l += [KconfigCheck('security_policy', 'defconfig', 'SECURITY', 'y')] # and choose your favourite LSM
497 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY', 'y')] # and choose your favourite LSM
498 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_YAMA', 'y')]
499 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DISABLE', 'is not set')]
500 l += [KconfigCheck('security_policy', 'clipos', 'SECURITY_LOCKDOWN_LSM', 'y')]
501 l += [KconfigCheck('security_policy', 'clipos', 'SECURITY_LOCKDOWN_LSM_EARLY', 'y')]
502 l += [KconfigCheck('security_policy', 'clipos', 'LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y')]
503 l += [KconfigCheck('security_policy', 'my', 'SECURITY_WRITABLE_HOOKS', 'is not set')] # refers to SECURITY_SELINUX_DISABLE
504 l += [KconfigCheck('security_policy', 'my', 'SECURITY_SAFESETID', 'y')]
505 loadpin_is_set = KconfigCheck('security_policy', 'my', 'SECURITY_LOADPIN', 'y')
506 l += [loadpin_is_set] # needs userspace support
507 l += [AND(KconfigCheck('security_policy', 'my', 'SECURITY_LOADPIN_ENFORCE', 'y'),
510 # 'cut_attack_surface', 'defconfig'
511 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'BPF_UNPRIV_DEFAULT_OFF', 'y'),
512 bpf_syscall_not_set)] # see unprivileged_bpf_disabled
513 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP', 'y')]
514 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP_FILTER', 'y')]
515 if arch in ('X86_64', 'ARM64', 'X86_32'):
516 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'STRICT_DEVMEM', 'y'),
517 devmem_not_set)] # refers to LOCKDOWN
519 # 'cut_attack_surface', 'kspp'
520 l += [KconfigCheck('cut_attack_surface', 'kspp', 'SECURITY_DMESG_RESTRICT', 'y')]
521 l += [KconfigCheck('cut_attack_surface', 'kspp', 'ACPI_CUSTOM_METHOD', 'is not set')] # refers to LOCKDOWN
522 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_BRK', 'is not set')]
523 l += [KconfigCheck('cut_attack_surface', 'kspp', 'DEVKMEM', 'is not set')] # refers to LOCKDOWN
524 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_VDSO', 'is not set')]
525 l += [KconfigCheck('cut_attack_surface', 'kspp', 'BINFMT_MISC', 'is not set')]
526 l += [KconfigCheck('cut_attack_surface', 'kspp', 'INET_DIAG', 'is not set')]
527 l += [KconfigCheck('cut_attack_surface', 'kspp', 'KEXEC', 'is not set')] # refers to LOCKDOWN
528 l += [KconfigCheck('cut_attack_surface', 'kspp', 'PROC_KCORE', 'is not set')] # refers to LOCKDOWN
529 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_PTYS', 'is not set')]
530 l += [KconfigCheck('cut_attack_surface', 'kspp', 'HIBERNATION', 'is not set')] # refers to LOCKDOWN
531 l += [KconfigCheck('cut_attack_surface', 'kspp', 'IA32_EMULATION', 'is not set')]
532 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_X32', 'is not set')]
533 l += [KconfigCheck('cut_attack_surface', 'kspp', 'MODIFY_LDT_SYSCALL', 'is not set')]
534 l += [KconfigCheck('cut_attack_surface', 'kspp', 'OABI_COMPAT', 'is not set')]
535 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_MSR', 'is not set')] # refers to LOCKDOWN
536 l += [modules_not_set]
537 l += [devmem_not_set]
538 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'IO_STRICT_DEVMEM', 'y'),
539 devmem_not_set)] # refers to LOCKDOWN
541 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'STRICT_DEVMEM', 'y'),
542 devmem_not_set)] # refers to LOCKDOWN
544 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y')] # 'vsyscall=none'
546 # 'cut_attack_surface', 'grsec'
547 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ZSMALLOC_STAT', 'is not set')]
548 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PAGE_OWNER', 'is not set')]
549 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_KMEMLEAK', 'is not set')]
550 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BINFMT_AOUT', 'is not set')]
551 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KPROBE_EVENTS', 'is not set')]
552 l += [KconfigCheck('cut_attack_surface', 'grsec', 'UPROBE_EVENTS', 'is not set')]
553 l += [KconfigCheck('cut_attack_surface', 'grsec', 'GENERIC_TRACER', 'is not set')] # refers to LOCKDOWN
554 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FUNCTION_TRACER', 'is not set')]
555 l += [KconfigCheck('cut_attack_surface', 'grsec', 'STACK_TRACER', 'is not set')]
556 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HIST_TRIGGERS', 'is not set')]
557 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BLK_DEV_IO_TRACE', 'is not set')]
558 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_VMCORE', 'is not set')]
559 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_PAGE_MONITOR', 'is not set')]
560 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USELIB', 'is not set')]
561 l += [KconfigCheck('cut_attack_surface', 'grsec', 'CHECKPOINT_RESTORE', 'is not set')]
562 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USERFAULTFD', 'is not set')]
563 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HWPOISON_INJECT', 'is not set')]
564 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MEM_SOFT_DIRTY', 'is not set')]
565 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEVPORT', 'is not set')] # refers to LOCKDOWN
566 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set')] # refers to LOCKDOWN
567 l += [KconfigCheck('cut_attack_surface', 'grsec', 'NOTIFIER_ERROR_INJECTION', 'is not set')]
568 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FAIL_FUTEX', 'is not set')]
569 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PUNIT_ATOM_DEBUG', 'is not set')]
570 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ACPI_CONFIGFS', 'is not set')]
571 l += [KconfigCheck('cut_attack_surface', 'grsec', 'EDAC_DEBUG', 'is not set')]
572 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DRM_I915_DEBUG', 'is not set')]
573 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BCACHE_CLOSURES_DEBUG', 'is not set')]
574 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DVB_C8SECTPFE', 'is not set')]
575 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_SLRAM', 'is not set')]
576 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_PHRAM', 'is not set')]
577 l += [KconfigCheck('cut_attack_surface', 'grsec', 'IO_URING', 'is not set')]
578 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCMP', 'is not set')]
579 l += [KconfigCheck('cut_attack_surface', 'grsec', 'RSEQ', 'is not set')]
580 l += [KconfigCheck('cut_attack_surface', 'grsec', 'LATENCYTOP', 'is not set')]
581 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCOV', 'is not set')]
582 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROVIDE_OHCI1394_DMA_INIT', 'is not set')]
583 l += [KconfigCheck('cut_attack_surface', 'grsec', 'SUNRPC_DEBUG', 'is not set')]
584 l += [AND(KconfigCheck('cut_attack_surface', 'grsec', 'PTDUMP_DEBUGFS', 'is not set'),
585 KconfigCheck('cut_attack_surface', 'grsec', 'X86_PTDUMP', 'is not set'))]
587 # 'cut_attack_surface', 'maintainer'
588 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'DRM_LEGACY', 'is not set')] # recommended by Daniel Vetter in /issues/38
589 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'FB', 'is not set')] # recommended by Daniel Vetter in /issues/38
590 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'VT', 'is not set')] # recommended by Daniel Vetter in /issues/38
591 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD', 'is not set')] # recommended by Denis Efremov in /pull/54
592 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD_RAWCMD', 'is not set')] # recommended by Denis Efremov in /pull/62
594 # 'cut_attack_surface', 'grapheneos'
595 l += [KconfigCheck('cut_attack_surface', 'grapheneos', 'AIO', 'is not set')]
597 # 'cut_attack_surface', 'clipos'
598 l += [KconfigCheck('cut_attack_surface', 'clipos', 'STAGING', 'is not set')]
599 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KSM', 'is not set')] # to prevent FLUSH+RELOAD attack
600 # l += [KconfigCheck('cut_attack_surface', 'clipos', 'IKCONFIG', 'is not set')] # no, IKCONFIG is needed for this check :)
601 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KALLSYMS', 'is not set')]
602 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_VSYSCALL_EMULATION', 'is not set')]
603 l += [KconfigCheck('cut_attack_surface', 'clipos', 'MAGIC_SYSRQ', 'is not set')]
604 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KEXEC_FILE', 'is not set')] # refers to LOCKDOWN (permissive)
605 l += [KconfigCheck('cut_attack_surface', 'clipos', 'USER_NS', 'is not set')] # user.max_user_namespaces=0
606 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_CPUID', 'is not set')]
607 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_IOPL_IOPERM', 'is not set')] # refers to LOCKDOWN
608 l += [KconfigCheck('cut_attack_surface', 'clipos', 'ACPI_TABLE_UPGRADE', 'is not set')] # refers to LOCKDOWN
609 l += [KconfigCheck('cut_attack_surface', 'clipos', 'EFI_CUSTOM_SSDT_OVERLAYS', 'is not set')]
610 l += [AND(KconfigCheck('cut_attack_surface', 'clipos', 'LDISC_AUTOLOAD', 'is not set'),
611 KconfigCheck('cut_attack_surface', 'clipos', 'LDISC_AUTOLOAD'))] # option presence check
612 if arch in ('X86_64', 'X86_32'):
613 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_INTEL_TSX_MODE_OFF', 'y')] # tsx=off
615 # 'cut_attack_surface', 'lockdown'
616 l += [bpf_syscall_not_set] # refers to LOCKDOWN
617 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'EFI_TEST', 'is not set')] # refers to LOCKDOWN
618 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'MMIOTRACE_TEST', 'is not set')] # refers to LOCKDOWN
619 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'KPROBES', 'is not set')] # refers to LOCKDOWN
621 # 'cut_attack_surface', 'my'
622 l += [OR(KconfigCheck('cut_attack_surface', 'my', 'TRIM_UNUSED_KSYMS', 'y'),
624 l += [KconfigCheck('cut_attack_surface', 'my', 'MMIOTRACE', 'is not set')] # refers to LOCKDOWN (permissive)
625 l += [KconfigCheck('cut_attack_surface', 'my', 'LIVEPATCH', 'is not set')]
626 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_DCCP', 'is not set')]
627 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_SCTP', 'is not set')]
628 l += [KconfigCheck('cut_attack_surface', 'my', 'FTRACE', 'is not set')] # refers to LOCKDOWN
629 l += [KconfigCheck('cut_attack_surface', 'my', 'VIDEO_VIVID', 'is not set')]
630 l += [KconfigCheck('cut_attack_surface', 'my', 'INPUT_EVBUG', 'is not set')] # Can be used as a keylogger
631 l += [KconfigCheck('cut_attack_surface', 'my', 'KGDB', 'is not set')]
634 if arch in ('X86_64', 'ARM64', 'X86_32'):
635 l += [KconfigCheck('harden_userspace', 'defconfig', 'INTEGRITY', 'y')]
637 l += [KconfigCheck('harden_userspace', 'my', 'INTEGRITY', 'y')]
639 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_PTR_AUTH', 'y')]
640 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_BTI', 'y')]
641 if arch in ('ARM', 'X86_32'):
642 l += [KconfigCheck('harden_userspace', 'defconfig', 'VMSPLIT_3G', 'y')]
643 if arch in ('X86_64', 'ARM64'):
644 l += [KconfigCheck('harden_userspace', 'clipos', 'ARCH_MMAP_RND_BITS', '32')]
645 if arch in ('X86_32', 'ARM'):
646 l += [KconfigCheck('harden_userspace', 'my', 'ARCH_MMAP_RND_BITS', '16')]
649 def add_cmdline_checks(l, arch):
650 # Calling the CmdlineCheck class constructor:
651 # CmdlineCheck(reason, decision, name, expected)
653 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
654 # when the tool doesn't check the cmdline.
656 # [!] Make sure that values of the options in CmdlineChecks need normalization.
657 # For more info see normalize_cmdline_options().
659 # A common pattern for checking the 'param_x' cmdline parameter
660 # that __overrides__ the 'PARAM_X_DEFAULT' kconfig option:
661 # l += [OR(CmdlineCheck(reason, decision, 'param_x', '1'),
662 # AND(KconfigCheck(reason, decision, 'PARAM_X_DEFAULT_ON', 'y'),
663 # CmdlineCheck(reason, decision, 'param_x, 'is not set')))]
665 # Here we don't check the kconfig options or minimal kernel version
666 # required for the cmdline parameters. That would make the checks
667 # very complex and not give a 100% guarantee anyway.
670 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', 'full'),
671 AND(KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y'),
672 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set')))]
674 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', '1'),
675 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set'))]
677 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', '1'),
678 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y'),
679 CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', 'is not set')))]
680 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_free', '1'),
681 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
682 CmdlineCheck('self_protection', 'kspp', 'init_on_free', 'is not set')),
683 AND(CmdlineCheck('self_protection', 'kspp', 'page_poison', '1'),
684 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'),
685 CmdlineCheck('self_protection', 'kspp', 'slub_debug', 'P')))]
686 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_nomerge'),
687 AND(KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set'),
688 CmdlineCheck('self_protection', 'kspp', 'slab_merge', 'is not set')))] # option presence check
689 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.strict', '1'),
690 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y'),
691 CmdlineCheck('self_protection', 'kspp', 'iommu.strict', 'is not set')))]
692 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', '0'),
693 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set'),
694 CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', 'is not set')))]
695 # The cmdline checks based on the kconfig recommendations of the KSPP project:
696 l += [OR(CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', '1'),
697 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y'),
698 CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', 'is not set')))]
699 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', '0'),
700 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
701 CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', 'is not set')))]
702 l += [OR(CmdlineCheck('self_protection', 'kspp', 'page_alloc.shuffle', '1'),
703 AND(KconfigCheck('self_protection', 'kspp', 'SHUFFLE_PAGE_ALLOCATOR', 'y'),
704 CmdlineCheck('self_protection', 'kspp', 'page_alloc.shuffle', 'is not set')))]
706 if arch in ('X86_64', 'ARM64', 'X86_32'):
707 l += [OR(CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', '1'),
708 AND(KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y'),
709 CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', 'is not set')))]
710 if arch in ('X86_64', 'X86_32'):
711 l += [CmdlineCheck('self_protection', 'kspp', 'pti', 'on')]
714 l += [OR(CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'none'),
715 AND(KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y'),
716 CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'is not set')))]
721 def print_unknown_options(checklist, parsed_options):
725 if o1.type != 'complex':
726 known_options.append(o1.name)
729 if o2.type != 'complex':
730 if hasattr(o2, 'name'):
731 known_options.append(o2.name)
734 assert(o3.type != 'complex'), \
735 'unexpected ComplexOptCheck inside {}'.format(o2.name)
736 if hasattr(o3, 'name'):
737 known_options.append(o3.name)
739 for option, value in parsed_options.items():
740 if option not in known_options:
741 print('[?] No check for option {} ({})'.format(option, value))
744 def print_checklist(mode, checklist, with_results):
748 output.append(o.json_dump(with_results))
749 print(json.dumps(output))
756 print('=' * sep_line_len)
757 print('{:^40}|{:^7}|{:^12}|{:^10}|{:^18}'.format('option name', 'type', 'desired val', 'decision', 'reason'), end='')
759 print('| {}'.format('check result'), end='')
761 print('=' * sep_line_len)
764 for opt in checklist:
766 if mode == 'show_ok':
767 if not opt.result.startswith('OK'):
769 if mode == 'show_fail':
770 if not opt.result.startswith('FAIL'):
772 opt.table_print(mode, with_results)
774 if mode == 'verbose':
775 print('-' * sep_line_len)
780 fail_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), checklist)))
782 ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), checklist)))
784 if mode == 'show_ok':
785 fail_suppressed = ' (suppressed in output)'
786 if mode == 'show_fail':
787 ok_suppressed = ' (suppressed in output)'
789 print('[+] Config check is finished: \'OK\' - {}{} / \'FAIL\' - {}{}'.format(ok_count, ok_suppressed, fail_count, fail_suppressed))
792 def populate_simple_opt_with_data(opt, data, data_type):
793 assert(opt.type != 'complex'), \
794 'unexpected ComplexOptCheck "{}"'.format(opt.name)
795 assert(opt.type in SIMPLE_OPTION_TYPES), \
796 'invalid opt type "{}"'.format(opt.type)
797 assert(data_type in SIMPLE_OPTION_TYPES), \
798 'invalid data type "{}"'.format(data_type)
800 if data_type != opt.type:
803 if data_type in ('kconfig', 'cmdline'):
804 opt.state = data.get(opt.name, None)
806 assert(data_type == 'version'), \
807 'unexpected data type "{}"'.format(data_type)
811 def populate_opt_with_data(opt, data, data_type):
812 if opt.type == 'complex':
814 if o.type == 'complex':
815 # Recursion for nested ComplexOptCheck objects
816 populate_opt_with_data(o, data, data_type)
818 populate_simple_opt_with_data(o, data, data_type)
820 assert(opt.type in ('kconfig', 'cmdline')), \
821 'bad type "{}" for a simple check'.format(opt.type)
822 populate_simple_opt_with_data(opt, data, data_type)
825 def populate_with_data(checklist, data, data_type):
826 for opt in checklist:
827 populate_opt_with_data(opt, data, data_type)
830 def perform_checks(checklist):
831 for opt in checklist:
835 def parse_kconfig_file(parsed_options, fname):
836 with open(fname, 'r') as f:
837 opt_is_on = re.compile("CONFIG_[a-zA-Z0-9_]*=[a-zA-Z0-9_\"]*")
838 opt_is_off = re.compile("# CONFIG_[a-zA-Z0-9_]* is not set")
840 for line in f.readlines():
845 if opt_is_on.match(line):
846 option, value = line.split('=', 1)
847 if value == 'is not set':
848 sys.exit('[!] ERROR: bad enabled kconfig option "{}"'.format(line))
849 elif opt_is_off.match(line):
850 option, value = line[2:].split(' ', 1)
851 if value != 'is not set':
852 sys.exit('[!] ERROR: bad disabled kconfig option "{}"'.format(line))
854 if option in parsed_options:
855 sys.exit('[!] ERROR: kconfig option "{}" exists multiple times'.format(line))
858 parsed_options[option] = value
861 def normalize_cmdline_options(option, value):
862 # Handle special cases
864 # Don't normalize the pti value since
865 # the Linux kernel doesn't use kstrtobool() for pti.
866 # See pti_check_boottime_disable() in linux/arch/x86/mm/pti.c
869 # Implement a limited part of the kstrtobool() logic
870 if value in ('1', 'on', 'On', 'ON', 'y', 'Y', 'yes', 'Yes', 'YES'):
872 if value in ('0', 'off', 'Off', 'OFF', 'n', 'N', 'no', 'No', 'NO'):
875 # Preserve unique values
879 def parse_cmdline_file(parsed_options, fname):
880 with open(fname, 'r') as f:
886 sys.exit('[!] ERROR: more than one line in "{}"'.format(fname))
890 name, value = opt.split('=', 1)
893 value = '' # '' is not None
894 value = normalize_cmdline_options(name, value)
895 parsed_options[name] = value
901 # - reporting about unknown kernel options in the kconfig
902 # - verbose printing of ComplexOptCheck items
903 # * json mode for printing the results in JSON format
904 report_modes = ['verbose', 'json', 'show_ok', 'show_fail']
905 supported_archs = ['X86_64', 'X86_32', 'ARM64', 'ARM']
906 parser = ArgumentParser(prog='kconfig-hardened-check',
907 description='A tool for checking the security hardening options of the Linux kernel')
908 parser.add_argument('--version', action='version', version='%(prog)s ' + __version__)
909 parser.add_argument('-p', '--print', choices=supported_archs,
910 help='print security hardening preferences for the selected architecture')
911 parser.add_argument('-c', '--config',
912 help='check the kernel kconfig file against these preferences')
913 parser.add_argument('-l', '--cmdline',
914 help='check the kernel cmdline file against these preferences')
915 parser.add_argument('-m', '--mode', choices=report_modes,
916 help='choose the report mode')
917 args = parser.parse_args()
923 print('[+] Special report mode: {}'.format(mode))
925 config_checklist = []
929 sys.exit('[!] ERROR: --config and --print can\'t be used together')
932 print('[+] Kconfig file to check: {}'.format(args.config))
934 print('[+] Kernel cmdline file to check: {}'.format(args.cmdline))
936 arch, msg = detect_arch(args.config, supported_archs)
938 sys.exit('[!] ERROR: {}'.format(msg))
940 print('[+] Detected architecture: {}'.format(arch))
942 kernel_version, msg = detect_version(args.config)
943 if not kernel_version:
944 sys.exit('[!] ERROR: {}'.format(msg))
946 print('[+] Detected kernel version: {}.{}'.format(kernel_version[0], kernel_version[1]))
948 # add relevant kconfig checks to the checklist
949 add_kconfig_checks(config_checklist, arch)
952 # add relevant cmdline checks to the checklist
953 add_cmdline_checks(config_checklist, arch)
955 # populate the checklist with the parsed kconfig data
956 parsed_kconfig_options = OrderedDict()
957 parse_kconfig_file(parsed_kconfig_options, args.config)
958 populate_with_data(config_checklist, parsed_kconfig_options, 'kconfig')
959 populate_with_data(config_checklist, kernel_version, 'version')
962 # populate the checklist with the parsed kconfig data
963 parsed_cmdline_options = OrderedDict()
964 parse_cmdline_file(parsed_cmdline_options, args.cmdline)
965 populate_with_data(config_checklist, parsed_cmdline_options, 'cmdline')
967 # now everything is ready for performing the checks
968 perform_checks(config_checklist)
970 # finally print the results
971 if mode == 'verbose':
972 print_unknown_options(config_checklist, parsed_kconfig_options)
973 print_checklist(mode, config_checklist, True)
977 sys.exit('[!] ERROR: checking cmdline doesn\'t work without checking kconfig')
980 if mode in ('show_ok', 'show_fail'):
981 sys.exit('[!] ERROR: wrong mode "{}" for --print'.format(mode))
983 add_kconfig_checks(config_checklist, arch)
984 add_cmdline_checks(config_checklist, arch)
986 print('[+] Printing kernel security hardening preferences for {}...'.format(arch))
987 print_checklist(mode, config_checklist, False)