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)
22 # spec_store_bypass_disable=on
24 # l1d_flush=on (a part of the l1tf option)
32 # sysrq_always_enabled
37 # Hardware tag-based KASAN with arm64 Memory Tagging Extension (MTE):
39 # kasan.stacktrace=off
42 # N.B. Hardening sysctls:
43 # kernel.kptr_restrict=2 (or 1?)
44 # kernel.dmesg_restrict=1 (also see the kconfig option)
45 # kernel.perf_event_paranoid=3
46 # kernel.kexec_load_disabled=1
47 # kernel.yama.ptrace_scope=3
48 # user.max_user_namespaces=0
49 # what about bpf_jit_enable?
50 # kernel.unprivileged_bpf_disabled=1
51 # net.core.bpf_jit_harden=2
52 # vm.unprivileged_userfaultfd=0
53 # (at first, it disabled unprivileged userfaultfd,
54 # and since v5.11 it enables unprivileged userfaultfd for user-mode only)
55 # vm.mmap_min_addr has a good value
56 # dev.tty.ldisc_autoload=0
57 # fs.protected_symlinks=1
58 # fs.protected_hardlinks=1
59 # fs.protected_fifos=2
60 # fs.protected_regular=2
62 # kernel.modules_disabled=1
63 # kernel.randomize_va_space = 2
66 # pylint: disable=missing-module-docstring,missing-class-docstring,missing-function-docstring
67 # pylint: disable=line-too-long,invalid-name,too-many-branches,too-many-statements
71 from argparse import ArgumentParser
72 from collections import OrderedDict
75 from .__about__ import __version__
77 SIMPLE_OPTION_TYPES = ('kconfig', 'version', 'cmdline')
80 # Constructor without the 'expected' parameter is for option presence checks (any value is OK)
81 def __init__(self, reason, decision, name, expected=None):
82 assert(reason and decision and name), \
83 'invalid {} check for "{}"'.format(self.__class__.__name__, name)
85 self.expected = expected
86 self.decision = decision
96 # handle the option presence check
97 if self.expected is None:
98 if self.state is None:
99 self.result = 'FAIL: not present'
101 self.result = 'OK: is present'
104 # handle the option value check
105 if self.expected == self.state:
107 elif self.state is None:
108 if self.expected == 'is not set':
109 self.result = 'OK: not found'
111 self.result = 'FAIL: not found'
113 self.result = 'FAIL: "' + self.state + '"'
115 def table_print(self, _mode, with_results):
116 if self.expected is None:
119 expected = self.expected
120 print('{:<40}|{:^7}|{:^12}|{:^10}|{:^18}'.format(self.name, self.type, expected, self.decision, self.reason), end='')
122 print('| {}'.format(self.result), end='')
124 def json_dump(self, with_results):
125 dump = [self.name, self.type, self.expected, self.decision, self.reason]
127 dump.append(self.result)
131 class KconfigCheck(OptCheck):
132 def __init__(self, *args, **kwargs):
133 super().__init__(*args, **kwargs)
134 self.name = 'CONFIG_' + self.name
141 class CmdlineCheck(OptCheck):
148 def __init__(self, ver_expected):
149 self.ver_expected = ver_expected
158 if self.ver[0] > self.ver_expected[0]:
159 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
161 if self.ver[0] < self.ver_expected[0]:
162 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
164 if self.ver[1] >= self.ver_expected[1]:
165 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
167 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
169 def table_print(self, _mode, with_results):
170 ver_req = 'kernel version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
171 print('{:<91}'.format(ver_req), end='')
173 print('| {}'.format(self.result), end='')
176 class ComplexOptCheck:
177 def __init__(self, *opts):
180 'empty {} check'.format(self.__class__.__name__)
181 assert(len(self.opts) != 1), \
182 'useless {} check: {}'.format(self.__class__.__name__, opts)
183 assert(isinstance(opts[0], (KconfigCheck, CmdlineCheck))), \
184 'invalid {} check: {}'.format(self.__class__.__name__, opts)
193 return self.opts[0].name
197 return self.opts[0].expected
199 def table_print(self, mode, with_results):
200 if mode == 'verbose':
201 print(' {:87}'.format('<<< ' + self.__class__.__name__ + ' >>>'), end='')
203 print('| {}'.format(self.result), end='')
206 o.table_print(mode, with_results)
209 o.table_print(mode, False)
211 print('| {}'.format(self.result), end='')
213 def json_dump(self, with_results):
214 dump = self.opts[0].json_dump(False)
216 dump.append(self.result)
220 class OR(ComplexOptCheck):
221 # self.opts[0] is the option that this OR-check is about.
223 # OR(<X_is_hardened>, <X_is_disabled>)
224 # OR(<X_is_hardened>, <old_X_is_hardened>)
226 for i, opt in enumerate(self.opts):
228 if opt.result.startswith('OK'):
229 self.result = opt.result
230 # Add more info for additional checks:
232 if opt.result == 'OK':
233 self.result = 'OK: {} "{}"'.format(opt.name, opt.expected)
234 elif opt.result == 'OK: not found':
235 self.result = 'OK: {} not found'.format(opt.name)
236 elif opt.result == 'OK: is present':
237 self.result = 'OK: {} is present'.format(opt.name)
239 # VersionCheck provides enough info
240 assert(opt.result.startswith('OK: version')), \
241 'unexpected OK description "{}"'.format(opt.result)
243 self.result = self.opts[0].result
246 class AND(ComplexOptCheck):
247 # self.opts[0] is the option that this AND-check is about.
249 # AND(<suboption>, <main_option>)
250 # Suboption is not checked if checking of the main_option is failed.
251 # AND(<X_is_disabled>, <old_X_is_disabled>)
253 for i, opt in reversed(list(enumerate(self.opts))):
256 self.result = opt.result
258 if not opt.result.startswith('OK'):
259 # This FAIL is caused by additional checks,
260 # and not by the main option that this AND-check is about.
261 # Describe the reason of the FAIL.
262 if opt.result.startswith('FAIL: \"') or opt.result == 'FAIL: not found':
263 self.result = 'FAIL: {} not "{}"'.format(opt.name, opt.expected)
264 elif opt.result == 'FAIL: not present':
265 self.result = 'FAIL: {} not present'.format(opt.name)
267 # VersionCheck provides enough info
268 self.result = opt.result
269 assert(opt.result.startswith('FAIL: version')), \
270 'unexpected FAIL description "{}"'.format(opt.result)
274 def detect_arch(fname, archs):
275 with open(fname, 'r') as f:
276 arch_pattern = re.compile("CONFIG_[a-zA-Z0-9_]*=y")
278 for line in f.readlines():
279 if arch_pattern.match(line):
280 option, _ = line[7:].split('=', 1)
285 return None, 'more than one supported architecture is detected'
287 return None, 'failed to detect architecture'
291 def detect_version(fname):
292 with open(fname, 'r') as f:
293 ver_pattern = re.compile("# Linux/.* Kernel Configuration")
294 for line in f.readlines():
295 if ver_pattern.match(line):
299 ver_numbers = ver_str.split('.')
300 if len(ver_numbers) < 3 or not ver_numbers[0].isdigit() or not ver_numbers[1].isdigit():
301 msg = 'failed to parse the version "' + ver_str + '"'
303 return (int(ver_numbers[0]), int(ver_numbers[1])), None
304 return None, 'no kernel version detected'
307 def add_kconfig_checks(l, arch):
308 # Calling the KconfigCheck class constructor:
309 # KconfigCheck(reason, decision, name, expected)
311 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
312 # when the tool doesn't check the cmdline.
314 efi_not_set = KconfigCheck('-', '-', 'EFI', 'is not set')
315 cc_is_gcc = KconfigCheck('-', '-', 'CC_IS_GCC', 'y')
316 cc_is_clang = KconfigCheck('-', '-', 'CC_IS_CLANG', 'y')
318 modules_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'MODULES', 'is not set')
319 devmem_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'DEVMEM', 'is not set') # refers to LOCKDOWN
320 bpf_syscall_not_set = KconfigCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set') # refers to LOCKDOWN
322 # 'self_protection', 'defconfig'
323 l += [KconfigCheck('self_protection', 'defconfig', 'BUG', 'y')]
324 l += [KconfigCheck('self_protection', 'defconfig', 'SLUB_DEBUG', 'y')]
325 l += [AND(KconfigCheck('self_protection', 'defconfig', 'GCC_PLUGINS', 'y'),
327 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR', 'y'),
328 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR', 'y'),
329 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_REGULAR', 'y'),
330 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_AUTO', 'y'),
331 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
332 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_STRONG', 'y'),
333 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
334 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_KERNEL_RWX', 'y'),
335 KconfigCheck('self_protection', 'defconfig', 'DEBUG_RODATA', 'y'))] # before v4.11
336 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_MODULE_RWX', 'y'),
337 KconfigCheck('self_protection', 'defconfig', 'DEBUG_SET_MODULE_RONX', 'y'),
338 modules_not_set)] # DEBUG_SET_MODULE_RONX was before v4.11
339 l += [OR(KconfigCheck('self_protection', 'defconfig', 'REFCOUNT_FULL', 'y'),
340 VersionCheck((5, 5)))] # REFCOUNT_FULL is enabled by default since v5.5
341 l += [KconfigCheck('self_protection', 'defconfig', 'THREAD_INFO_IN_TASK', 'y')]
342 iommu_support_is_set = KconfigCheck('self_protection', 'defconfig', 'IOMMU_SUPPORT', 'y')
343 l += [iommu_support_is_set] # is needed for mitigating DMA attacks
344 if arch in ('X86_64', 'ARM64', 'X86_32'):
345 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y')]
346 if arch in ('X86_64', 'ARM64'):
347 l += [KconfigCheck('self_protection', 'defconfig', 'VMAP_STACK', 'y')]
348 if arch in ('X86_64', 'X86_32'):
349 l += [KconfigCheck('self_protection', 'defconfig', 'MICROCODE', 'y')] # is needed for mitigating CPU bugs
350 l += [KconfigCheck('self_protection', 'defconfig', 'RETPOLINE', 'y')]
351 l += [KconfigCheck('self_protection', 'defconfig', 'X86_SMAP', 'y')]
352 l += [KconfigCheck('self_protection', 'defconfig', 'SYN_COOKIES', 'y')] # another reason?
353 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_UMIP', 'y'),
354 KconfigCheck('self_protection', 'defconfig', 'X86_INTEL_UMIP', 'y'))]
355 if arch in ('ARM64', 'ARM'):
356 l += [KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_PER_TASK', 'y')]
358 l += [KconfigCheck('self_protection', 'defconfig', 'PAGE_TABLE_ISOLATION', 'y')]
359 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MEMORY', 'y')]
360 l += [AND(KconfigCheck('self_protection', 'defconfig', 'INTEL_IOMMU', 'y'),
361 iommu_support_is_set)]
362 l += [AND(KconfigCheck('self_protection', 'defconfig', 'AMD_IOMMU', 'y'),
363 iommu_support_is_set)]
365 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PAN', 'y')]
366 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_EPAN', 'y')]
367 l += [KconfigCheck('self_protection', 'defconfig', 'UNMAP_KERNEL_AT_EL0', 'y')]
368 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_EL2_VECTORS', 'y'),
369 AND(KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y'),
370 VersionCheck((5, 9))))] # HARDEN_EL2_VECTORS was included in RANDOMIZE_BASE in v5.9
371 l += [KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y')]
372 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PTR_AUTH_KERNEL', 'y')]
373 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_BTI_KERNEL', 'y')]
374 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y'),
375 VersionCheck((5, 10)))] # HARDEN_BRANCH_PREDICTOR is enabled by default since v5.10
376 l += [KconfigCheck('self_protection', 'defconfig', 'MITIGATE_SPECTRE_BRANCH_HISTORY', 'y')]
377 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_MTE', 'y')]
378 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MODULE_REGION_FULL', 'y')]
380 l += [KconfigCheck('self_protection', 'defconfig', 'CPU_SW_DOMAIN_PAN', 'y')]
381 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y')]
382 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_HISTORY', 'y')]
384 # 'self_protection', 'kspp'
385 l += [KconfigCheck('self_protection', 'kspp', 'BUG_ON_DATA_CORRUPTION', 'y')]
386 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_WX', 'y')]
387 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_STACK_END_CHECK', 'y')]
388 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_HARDENED', 'y')]
389 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_RANDOM', 'y')]
390 l += [KconfigCheck('self_protection', 'kspp', 'SHUFFLE_PAGE_ALLOCATOR', 'y')]
391 l += [KconfigCheck('self_protection', 'kspp', 'FORTIFY_SOURCE', 'y')]
392 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_LIST', 'y')]
393 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_SG', 'y')]
394 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_CREDENTIALS', 'y')]
395 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_NOTIFIERS', 'y')]
396 l += [KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y')]
397 l += [AND(KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_LATENT_ENTROPY', 'y'),
399 l += [KconfigCheck('self_protection', 'kspp', 'KFENCE', 'y')]
400 l += [KconfigCheck('self_protection', 'kspp', 'WERROR', 'y')]
401 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y')]
402 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set')] # true if IOMMU_DEFAULT_DMA_STRICT is set
403 l += [KconfigCheck('self_protection', 'kspp', 'ZERO_CALL_USED_REGS', 'y')]
404 randstruct_is_set = OR(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_FULL', 'y'),
405 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT', 'y'))
406 l += [randstruct_is_set]
407 hardened_usercopy_is_set = KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y')
408 l += [hardened_usercopy_is_set]
409 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
410 hardened_usercopy_is_set)]
411 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_PAGESPAN', 'is not set'),
412 hardened_usercopy_is_set)]
413 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG', 'y'),
415 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_ALL', 'y'),
417 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_SHA512', 'y'),
419 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_FORCE', 'y'),
420 modules_not_set)] # refers to LOCKDOWN
421 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_STACK_ALL_ZERO', 'y'),
422 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y'))]
423 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
424 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'))]
425 # CONFIG_INIT_ON_FREE_DEFAULT_ON was added in v5.3.
426 # CONFIG_PAGE_POISONING_ZERO was removed in v5.11.
427 # Starting from v5.11 CONFIG_PAGE_POISONING unconditionally checks
428 # the 0xAA poison pattern on allocation.
429 # That brings higher performance penalty.
430 if arch in ('X86_64', 'ARM64', 'X86_32'):
431 stackleak_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STACKLEAK', 'y')
432 l += [AND(stackleak_is_set, cc_is_gcc)]
433 l += [KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y')]
434 if arch in ('X86_64', 'X86_32'):
435 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_CORE', 'y')]
436 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '65536')]
437 if arch in ('ARM64', 'ARM'):
438 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '32768')]
439 l += [KconfigCheck('self_protection', 'kspp', 'SYN_COOKIES', 'y')] # another reason?
441 l += [KconfigCheck('self_protection', 'kspp', 'ARM64_SW_TTBR0_PAN', 'y')]
443 l += [KconfigCheck('self_protection', 'kspp', 'PAGE_TABLE_ISOLATION', 'y')]
444 l += [KconfigCheck('self_protection', 'kspp', 'HIGHMEM64G', 'y')]
445 l += [KconfigCheck('self_protection', 'kspp', 'X86_PAE', 'y')]
447 # 'self_protection', 'maintainer'
448 ubsan_bounds_is_set = KconfigCheck('self_protection', 'maintainer', 'UBSAN_BOUNDS', 'y') # only array index bounds checking
449 l += [ubsan_bounds_is_set] # recommended by Kees Cook in /issues/53
450 if arch in ('X86_64', 'ARM64', 'X86_32'): # ARCH_HAS_UBSAN_SANITIZE_ALL is not enabled for ARM
451 l += [AND(KconfigCheck('self_protection', 'maintainer', 'UBSAN_SANITIZE_ALL', 'y'),
452 ubsan_bounds_is_set)] # recommended by Kees Cook in /issues/53
453 l += [AND(KconfigCheck('self_protection', 'maintainer', 'UBSAN_TRAP', 'y'),
454 ubsan_bounds_is_set)] # recommended by Kees Cook in /issues/53
456 # 'self_protection', 'clipos'
457 l += [KconfigCheck('self_protection', 'clipos', 'DEBUG_VIRTUAL', 'y')]
458 l += [KconfigCheck('self_protection', 'clipos', 'STATIC_USERMODEHELPER', 'y')] # needs userspace support
459 l += [OR(KconfigCheck('self_protection', 'clipos', 'EFI_DISABLE_PCI_DMA', 'y'),
461 l += [KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set')]
462 l += [KconfigCheck('self_protection', 'clipos', 'RANDOM_TRUST_BOOTLOADER', 'is not set')]
463 l += [KconfigCheck('self_protection', 'clipos', 'RANDOM_TRUST_CPU', 'is not set')]
464 l += [AND(KconfigCheck('self_protection', 'clipos', 'RANDSTRUCT_PERFORMANCE', 'is not set'),
465 KconfigCheck('self_protection', 'clipos', 'GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set'),
467 if arch in ('X86_64', 'ARM64', 'X86_32'):
468 l += [AND(KconfigCheck('self_protection', 'clipos', 'STACKLEAK_METRICS', 'is not set'),
471 l += [AND(KconfigCheck('self_protection', 'clipos', 'STACKLEAK_RUNTIME_DISABLE', 'is not set'),
474 if arch in ('X86_64', 'X86_32'):
475 l += [AND(KconfigCheck('self_protection', 'clipos', 'INTEL_IOMMU_DEFAULT_ON', 'y'),
476 iommu_support_is_set)]
478 l += [AND(KconfigCheck('self_protection', 'clipos', 'INTEL_IOMMU_SVM', 'y'),
479 iommu_support_is_set)]
481 l += [AND(KconfigCheck('self_protection', 'clipos', 'INTEL_IOMMU', 'y'),
482 iommu_support_is_set)]
484 # 'self_protection', 'my'
485 l += [OR(KconfigCheck('self_protection', 'my', 'RESET_ATTACK_MITIGATION', 'y'),
486 efi_not_set)] # needs userspace support (systemd)
488 l += [KconfigCheck('self_protection', 'my', 'SLS', 'y')] # vs CVE-2021-26341 in Straight-Line-Speculation
489 l += [AND(KconfigCheck('self_protection', 'my', 'AMD_IOMMU_V2', 'y'),
490 iommu_support_is_set)]
492 l += [KconfigCheck('self_protection', 'my', 'SHADOW_CALL_STACK', 'y')] # maybe it's alternative to STACKPROTECTOR_STRONG
493 l += [KconfigCheck('self_protection', 'my', 'KASAN_HW_TAGS', 'y')]
494 cfi_clang_is_set = KconfigCheck('self_protection', 'my', 'CFI_CLANG', 'y')
495 l += [cfi_clang_is_set]
496 l += [AND(KconfigCheck('self_protection', 'my', 'CFI_PERMISSIVE', 'is not set'),
500 if arch in ('X86_64', 'ARM64', 'X86_32'):
501 l += [KconfigCheck('security_policy', 'defconfig', 'SECURITY', 'y')] # and choose your favourite LSM
503 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY', 'y')] # and choose your favourite LSM
504 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_YAMA', 'y')]
505 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LANDLOCK', 'y')]
506 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DISABLE', 'is not set')]
507 l += [KconfigCheck('security_policy', 'clipos', 'SECURITY_LOCKDOWN_LSM', 'y')]
508 l += [KconfigCheck('security_policy', 'clipos', 'SECURITY_LOCKDOWN_LSM_EARLY', 'y')]
509 l += [KconfigCheck('security_policy', 'clipos', 'LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y')]
510 l += [KconfigCheck('security_policy', 'my', 'SECURITY_WRITABLE_HOOKS', 'is not set')] # refers to SECURITY_SELINUX_DISABLE
511 l += [KconfigCheck('security_policy', 'my', 'SECURITY_SAFESETID', 'y')]
512 loadpin_is_set = KconfigCheck('security_policy', 'my', 'SECURITY_LOADPIN', 'y')
513 l += [loadpin_is_set] # needs userspace support
514 l += [AND(KconfigCheck('security_policy', 'my', 'SECURITY_LOADPIN_ENFORCE', 'y'),
517 # 'cut_attack_surface', 'defconfig'
518 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'BPF_UNPRIV_DEFAULT_OFF', 'y'),
519 bpf_syscall_not_set)] # see unprivileged_bpf_disabled
520 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP', 'y')]
521 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP_FILTER', 'y')]
522 if arch in ('X86_64', 'ARM64', 'X86_32'):
523 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'STRICT_DEVMEM', 'y'),
524 devmem_not_set)] # refers to LOCKDOWN
526 # 'cut_attack_surface', 'kspp'
527 l += [KconfigCheck('cut_attack_surface', 'kspp', 'SECURITY_DMESG_RESTRICT', 'y')]
528 l += [KconfigCheck('cut_attack_surface', 'kspp', 'ACPI_CUSTOM_METHOD', 'is not set')] # refers to LOCKDOWN
529 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_BRK', 'is not set')]
530 l += [KconfigCheck('cut_attack_surface', 'kspp', 'DEVKMEM', 'is not set')] # refers to LOCKDOWN
531 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_VDSO', 'is not set')]
532 l += [KconfigCheck('cut_attack_surface', 'kspp', 'BINFMT_MISC', 'is not set')]
533 l += [KconfigCheck('cut_attack_surface', 'kspp', 'INET_DIAG', 'is not set')]
534 l += [KconfigCheck('cut_attack_surface', 'kspp', 'KEXEC', 'is not set')] # refers to LOCKDOWN
535 l += [KconfigCheck('cut_attack_surface', 'kspp', 'PROC_KCORE', 'is not set')] # refers to LOCKDOWN
536 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_PTYS', 'is not set')]
537 l += [KconfigCheck('cut_attack_surface', 'kspp', 'HIBERNATION', 'is not set')] # refers to LOCKDOWN
538 l += [KconfigCheck('cut_attack_surface', 'kspp', 'IA32_EMULATION', 'is not set')]
539 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_X32', 'is not set')]
540 l += [KconfigCheck('cut_attack_surface', 'kspp', 'MODIFY_LDT_SYSCALL', 'is not set')]
541 l += [KconfigCheck('cut_attack_surface', 'kspp', 'OABI_COMPAT', 'is not set')]
542 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_MSR', 'is not set')] # refers to LOCKDOWN
543 l += [modules_not_set]
544 l += [devmem_not_set]
545 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'IO_STRICT_DEVMEM', 'y'),
546 devmem_not_set)] # refers to LOCKDOWN
548 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'STRICT_DEVMEM', 'y'),
549 devmem_not_set)] # refers to LOCKDOWN
551 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y')] # 'vsyscall=none'
553 # 'cut_attack_surface', 'grsec'
554 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ZSMALLOC_STAT', 'is not set')]
555 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PAGE_OWNER', 'is not set')]
556 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_KMEMLEAK', 'is not set')]
557 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BINFMT_AOUT', 'is not set')]
558 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KPROBE_EVENTS', 'is not set')]
559 l += [KconfigCheck('cut_attack_surface', 'grsec', 'UPROBE_EVENTS', 'is not set')]
560 l += [KconfigCheck('cut_attack_surface', 'grsec', 'GENERIC_TRACER', 'is not set')] # refers to LOCKDOWN
561 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FUNCTION_TRACER', 'is not set')]
562 l += [KconfigCheck('cut_attack_surface', 'grsec', 'STACK_TRACER', 'is not set')]
563 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HIST_TRIGGERS', 'is not set')]
564 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BLK_DEV_IO_TRACE', 'is not set')]
565 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_VMCORE', 'is not set')]
566 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_PAGE_MONITOR', 'is not set')]
567 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USELIB', 'is not set')]
568 l += [KconfigCheck('cut_attack_surface', 'grsec', 'CHECKPOINT_RESTORE', 'is not set')]
569 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USERFAULTFD', 'is not set')]
570 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HWPOISON_INJECT', 'is not set')]
571 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MEM_SOFT_DIRTY', 'is not set')]
572 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEVPORT', 'is not set')] # refers to LOCKDOWN
573 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set')] # refers to LOCKDOWN
574 l += [KconfigCheck('cut_attack_surface', 'grsec', 'NOTIFIER_ERROR_INJECTION', 'is not set')]
575 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FAIL_FUTEX', 'is not set')]
576 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PUNIT_ATOM_DEBUG', 'is not set')]
577 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ACPI_CONFIGFS', 'is not set')]
578 l += [KconfigCheck('cut_attack_surface', 'grsec', 'EDAC_DEBUG', 'is not set')]
579 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DRM_I915_DEBUG', 'is not set')]
580 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BCACHE_CLOSURES_DEBUG', 'is not set')]
581 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DVB_C8SECTPFE', 'is not set')]
582 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_SLRAM', 'is not set')]
583 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_PHRAM', 'is not set')]
584 l += [KconfigCheck('cut_attack_surface', 'grsec', 'IO_URING', 'is not set')]
585 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCMP', 'is not set')]
586 l += [KconfigCheck('cut_attack_surface', 'grsec', 'RSEQ', 'is not set')]
587 l += [KconfigCheck('cut_attack_surface', 'grsec', 'LATENCYTOP', 'is not set')]
588 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCOV', 'is not set')]
589 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROVIDE_OHCI1394_DMA_INIT', 'is not set')]
590 l += [KconfigCheck('cut_attack_surface', 'grsec', 'SUNRPC_DEBUG', 'is not set')]
591 l += [AND(KconfigCheck('cut_attack_surface', 'grsec', 'PTDUMP_DEBUGFS', 'is not set'),
592 KconfigCheck('cut_attack_surface', 'grsec', 'X86_PTDUMP', 'is not set'))]
594 # 'cut_attack_surface', 'maintainer'
595 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'DRM_LEGACY', 'is not set')] # recommended by Daniel Vetter in /issues/38
596 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'FB', 'is not set')] # recommended by Daniel Vetter in /issues/38
597 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'VT', 'is not set')] # recommended by Daniel Vetter in /issues/38
598 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD', 'is not set')] # recommended by Denis Efremov in /pull/54
599 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD_RAWCMD', 'is not set')] # recommended by Denis Efremov in /pull/62
601 # 'cut_attack_surface', 'grapheneos'
602 l += [KconfigCheck('cut_attack_surface', 'grapheneos', 'AIO', 'is not set')]
604 # 'cut_attack_surface', 'clipos'
605 l += [KconfigCheck('cut_attack_surface', 'clipos', 'STAGING', 'is not set')]
606 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KSM', 'is not set')] # to prevent FLUSH+RELOAD attack
607 # l += [KconfigCheck('cut_attack_surface', 'clipos', 'IKCONFIG', 'is not set')] # no, IKCONFIG is needed for this check :)
608 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KALLSYMS', 'is not set')]
609 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_VSYSCALL_EMULATION', 'is not set')]
610 l += [KconfigCheck('cut_attack_surface', 'clipos', 'MAGIC_SYSRQ', 'is not set')]
611 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KEXEC_FILE', 'is not set')] # refers to LOCKDOWN (permissive)
612 l += [KconfigCheck('cut_attack_surface', 'clipos', 'USER_NS', 'is not set')] # user.max_user_namespaces=0
613 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_CPUID', 'is not set')]
614 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_IOPL_IOPERM', 'is not set')] # refers to LOCKDOWN
615 l += [KconfigCheck('cut_attack_surface', 'clipos', 'ACPI_TABLE_UPGRADE', 'is not set')] # refers to LOCKDOWN
616 l += [KconfigCheck('cut_attack_surface', 'clipos', 'EFI_CUSTOM_SSDT_OVERLAYS', 'is not set')]
617 l += [AND(KconfigCheck('cut_attack_surface', 'clipos', 'LDISC_AUTOLOAD', 'is not set'),
618 KconfigCheck('cut_attack_surface', 'clipos', 'LDISC_AUTOLOAD'))] # option presence check
619 if arch in ('X86_64', 'X86_32'):
620 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_INTEL_TSX_MODE_OFF', 'y')] # tsx=off
622 # 'cut_attack_surface', 'lockdown'
623 l += [bpf_syscall_not_set] # refers to LOCKDOWN
624 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'EFI_TEST', 'is not set')] # refers to LOCKDOWN
625 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'MMIOTRACE_TEST', 'is not set')] # refers to LOCKDOWN
626 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'KPROBES', 'is not set')] # refers to LOCKDOWN
628 # 'cut_attack_surface', 'my'
629 l += [OR(KconfigCheck('cut_attack_surface', 'my', 'TRIM_UNUSED_KSYMS', 'y'),
631 l += [KconfigCheck('cut_attack_surface', 'my', 'MMIOTRACE', 'is not set')] # refers to LOCKDOWN (permissive)
632 l += [KconfigCheck('cut_attack_surface', 'my', 'LIVEPATCH', 'is not set')]
633 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_DCCP', 'is not set')]
634 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_SCTP', 'is not set')]
635 l += [KconfigCheck('cut_attack_surface', 'my', 'FTRACE', 'is not set')] # refers to LOCKDOWN
636 l += [KconfigCheck('cut_attack_surface', 'my', 'VIDEO_VIVID', 'is not set')]
637 l += [KconfigCheck('cut_attack_surface', 'my', 'INPUT_EVBUG', 'is not set')] # Can be used as a keylogger
638 l += [KconfigCheck('cut_attack_surface', 'my', 'KGDB', 'is not set')]
641 if arch in ('X86_64', 'ARM64', 'X86_32'):
642 l += [KconfigCheck('harden_userspace', 'defconfig', 'INTEGRITY', 'y')]
644 l += [KconfigCheck('harden_userspace', 'my', 'INTEGRITY', 'y')]
646 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_PTR_AUTH', 'y')]
647 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_BTI', 'y')]
648 if arch in ('ARM', 'X86_32'):
649 l += [KconfigCheck('harden_userspace', 'defconfig', 'VMSPLIT_3G', 'y')]
650 if arch in ('X86_64', 'ARM64'):
651 l += [KconfigCheck('harden_userspace', 'clipos', 'ARCH_MMAP_RND_BITS', '32')]
652 if arch in ('X86_32', 'ARM'):
653 l += [KconfigCheck('harden_userspace', 'my', 'ARCH_MMAP_RND_BITS', '16')]
656 def add_cmdline_checks(l, arch):
657 # Calling the CmdlineCheck class constructor:
658 # CmdlineCheck(reason, decision, name, expected)
660 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
661 # when the tool doesn't check the cmdline.
663 # [!] Make sure that values of the options in CmdlineChecks need normalization.
664 # For more info see normalize_cmdline_options().
666 # A common pattern for checking the 'param_x' cmdline parameter
667 # that __overrides__ the 'PARAM_X_DEFAULT' kconfig option:
668 # l += [OR(CmdlineCheck(reason, decision, 'param_x', '1'),
669 # AND(KconfigCheck(reason, decision, 'PARAM_X_DEFAULT_ON', 'y'),
670 # CmdlineCheck(reason, decision, 'param_x, 'is not set')))]
672 # Here we don't check the kconfig options or minimal kernel version
673 # required for the cmdline parameters. That would make the checks
674 # very complex and not give a 100% guarantee anyway.
676 # 'self_protection', 'defconfig'
678 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', 'full'),
679 AND(KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y'),
680 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set')))]
682 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', '1'),
683 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set'))]
685 # 'self_protection', 'kspp'
686 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', '1'),
687 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y'),
688 CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', 'is not set')))]
689 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_free', '1'),
690 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
691 CmdlineCheck('self_protection', 'kspp', 'init_on_free', 'is not set')),
692 AND(CmdlineCheck('self_protection', 'kspp', 'page_poison', '1'),
693 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'),
694 CmdlineCheck('self_protection', 'kspp', 'slub_debug', 'P')))]
695 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_nomerge'),
696 AND(KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set'),
697 CmdlineCheck('self_protection', 'kspp', 'slab_merge', 'is not set')))] # option presence check
698 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.strict', '1'),
699 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y'),
700 CmdlineCheck('self_protection', 'kspp', 'iommu.strict', 'is not set')))]
701 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', '0'),
702 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set'),
703 CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', 'is not set')))]
704 # The cmdline checks compatible with the kconfig recommendations of the KSPP project...
705 l += [CmdlineCheck('self_protection', 'kspp', 'nokaslr', 'is not set')]
706 l += [OR(CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', '1'),
707 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y'),
708 CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', 'is not set')))]
709 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', '0'),
710 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
711 CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', 'is not set')))] # ... the end
712 if arch in ('X86_64', 'ARM64', 'X86_32'):
713 l += [OR(CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', '1'),
714 AND(KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y'),
715 CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', 'is not set')))]
716 if arch in ('X86_64', 'X86_32'):
717 l += [CmdlineCheck('self_protection', 'kspp', 'pti', 'on')]
719 # 'self_protection', 'clipos'
720 l += [CmdlineCheck('self_protection', 'clipos', 'page_alloc.shuffle', '1')]
722 # 'cut_attack_surface', 'kspp'
724 l += [OR(CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'none'),
725 AND(KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y'),
726 CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'is not set')))]
728 # 'cut_attack_surface', 'grsec'
729 # The cmdline checks compatible with the kconfig options disabled by grsecurity...
730 l += [OR(CmdlineCheck('cut_attack_surface', 'grsec', 'debugfs', 'off'),
731 KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set'))] # ... the end
734 def print_unknown_options(checklist, parsed_options):
738 if o1.type != 'complex':
739 known_options.append(o1.name)
742 if o2.type != 'complex':
743 if hasattr(o2, 'name'):
744 known_options.append(o2.name)
747 assert(o3.type != 'complex'), \
748 'unexpected ComplexOptCheck inside {}'.format(o2.name)
749 if hasattr(o3, 'name'):
750 known_options.append(o3.name)
752 for option, value in parsed_options.items():
753 if option not in known_options:
754 print('[?] No check for option {} ({})'.format(option, value))
757 def print_checklist(mode, checklist, with_results):
761 output.append(o.json_dump(with_results))
762 print(json.dumps(output))
769 print('=' * sep_line_len)
770 print('{:^40}|{:^7}|{:^12}|{:^10}|{:^18}'.format('option name', 'type', 'desired val', 'decision', 'reason'), end='')
772 print('| {}'.format('check result'), end='')
774 print('=' * sep_line_len)
777 for opt in checklist:
779 if mode == 'show_ok':
780 if not opt.result.startswith('OK'):
782 if mode == 'show_fail':
783 if not opt.result.startswith('FAIL'):
785 opt.table_print(mode, with_results)
787 if mode == 'verbose':
788 print('-' * sep_line_len)
793 fail_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), checklist)))
795 ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), checklist)))
797 if mode == 'show_ok':
798 fail_suppressed = ' (suppressed in output)'
799 if mode == 'show_fail':
800 ok_suppressed = ' (suppressed in output)'
802 print('[+] Config check is finished: \'OK\' - {}{} / \'FAIL\' - {}{}'.format(ok_count, ok_suppressed, fail_count, fail_suppressed))
805 def populate_simple_opt_with_data(opt, data, data_type):
806 assert(opt.type != 'complex'), \
807 'unexpected ComplexOptCheck "{}"'.format(opt.name)
808 assert(opt.type in SIMPLE_OPTION_TYPES), \
809 'invalid opt type "{}"'.format(opt.type)
810 assert(data_type in SIMPLE_OPTION_TYPES), \
811 'invalid data type "{}"'.format(data_type)
813 if data_type != opt.type:
816 if data_type in ('kconfig', 'cmdline'):
817 opt.state = data.get(opt.name, None)
819 assert(data_type == 'version'), \
820 'unexpected data type "{}"'.format(data_type)
824 def populate_opt_with_data(opt, data, data_type):
825 if opt.type == 'complex':
827 if o.type == 'complex':
828 # Recursion for nested ComplexOptCheck objects
829 populate_opt_with_data(o, data, data_type)
831 populate_simple_opt_with_data(o, data, data_type)
833 assert(opt.type in ('kconfig', 'cmdline')), \
834 'bad type "{}" for a simple check'.format(opt.type)
835 populate_simple_opt_with_data(opt, data, data_type)
838 def populate_with_data(checklist, data, data_type):
839 for opt in checklist:
840 populate_opt_with_data(opt, data, data_type)
843 def perform_checks(checklist):
844 for opt in checklist:
848 def parse_kconfig_file(parsed_options, fname):
849 with open(fname, 'r') as f:
850 opt_is_on = re.compile("CONFIG_[a-zA-Z0-9_]*=[a-zA-Z0-9_\"]*")
851 opt_is_off = re.compile("# CONFIG_[a-zA-Z0-9_]* is not set")
853 for line in f.readlines():
858 if opt_is_on.match(line):
859 option, value = line.split('=', 1)
860 if value == 'is not set':
861 sys.exit('[!] ERROR: bad enabled kconfig option "{}"'.format(line))
862 elif opt_is_off.match(line):
863 option, value = line[2:].split(' ', 1)
864 if value != 'is not set':
865 sys.exit('[!] ERROR: bad disabled kconfig option "{}"'.format(line))
867 if option in parsed_options:
868 sys.exit('[!] ERROR: kconfig option "{}" exists multiple times'.format(line))
871 parsed_options[option] = value
874 def normalize_cmdline_options(option, value):
875 # Don't normalize the cmdline option values if
876 # the Linux kernel doesn't use kstrtobool() for them
878 # See pti_check_boottime_disable() in linux/arch/x86/mm/pti.c
880 if option == 'debugfs':
881 # See debugfs_kernel() in fs/debugfs/inode.c
884 # Implement a limited part of the kstrtobool() logic
885 if value in ('1', 'on', 'On', 'ON', 'y', 'Y', 'yes', 'Yes', 'YES'):
887 if value in ('0', 'off', 'Off', 'OFF', 'n', 'N', 'no', 'No', 'NO'):
890 # Preserve unique values
894 def parse_cmdline_file(parsed_options, fname):
895 with open(fname, 'r') as f:
901 sys.exit('[!] ERROR: more than one line in "{}"'.format(fname))
905 name, value = opt.split('=', 1)
908 value = '' # '' is not None
909 value = normalize_cmdline_options(name, value)
910 parsed_options[name] = value
916 # - reporting about unknown kernel options in the kconfig
917 # - verbose printing of ComplexOptCheck items
918 # * json mode for printing the results in JSON format
919 report_modes = ['verbose', 'json', 'show_ok', 'show_fail']
920 supported_archs = ['X86_64', 'X86_32', 'ARM64', 'ARM']
921 parser = ArgumentParser(prog='kconfig-hardened-check',
922 description='A tool for checking the security hardening options of the Linux kernel')
923 parser.add_argument('--version', action='version', version='%(prog)s ' + __version__)
924 parser.add_argument('-p', '--print', choices=supported_archs,
925 help='print security hardening preferences for the selected architecture')
926 parser.add_argument('-c', '--config',
927 help='check the kernel kconfig file against these preferences')
928 parser.add_argument('-l', '--cmdline',
929 help='check the kernel cmdline file against these preferences')
930 parser.add_argument('-m', '--mode', choices=report_modes,
931 help='choose the report mode')
932 args = parser.parse_args()
938 print('[+] Special report mode: {}'.format(mode))
940 config_checklist = []
944 sys.exit('[!] ERROR: --config and --print can\'t be used together')
947 print('[+] Kconfig file to check: {}'.format(args.config))
949 print('[+] Kernel cmdline file to check: {}'.format(args.cmdline))
951 arch, msg = detect_arch(args.config, supported_archs)
953 sys.exit('[!] ERROR: {}'.format(msg))
955 print('[+] Detected architecture: {}'.format(arch))
957 kernel_version, msg = detect_version(args.config)
958 if not kernel_version:
959 sys.exit('[!] ERROR: {}'.format(msg))
961 print('[+] Detected kernel version: {}.{}'.format(kernel_version[0], kernel_version[1]))
963 # add relevant kconfig checks to the checklist
964 add_kconfig_checks(config_checklist, arch)
967 # add relevant cmdline checks to the checklist
968 add_cmdline_checks(config_checklist, arch)
970 # populate the checklist with the parsed kconfig data
971 parsed_kconfig_options = OrderedDict()
972 parse_kconfig_file(parsed_kconfig_options, args.config)
973 populate_with_data(config_checklist, parsed_kconfig_options, 'kconfig')
974 populate_with_data(config_checklist, kernel_version, 'version')
977 # populate the checklist with the parsed kconfig data
978 parsed_cmdline_options = OrderedDict()
979 parse_cmdline_file(parsed_cmdline_options, args.cmdline)
980 populate_with_data(config_checklist, parsed_cmdline_options, 'cmdline')
982 # now everything is ready for performing the checks
983 perform_checks(config_checklist)
985 # finally print the results
986 if mode == 'verbose':
987 print_unknown_options(config_checklist, parsed_kconfig_options)
988 print_checklist(mode, config_checklist, True)
992 sys.exit('[!] ERROR: checking cmdline doesn\'t work without checking kconfig')
995 if mode in ('show_ok', 'show_fail'):
996 sys.exit('[!] ERROR: wrong mode "{}" for --print'.format(mode))
998 add_kconfig_checks(config_checklist, arch)
999 add_cmdline_checks(config_checklist, arch)
1001 print('[+] Printing kernel security hardening preferences for {}...'.format(arch))
1002 print_checklist(mode, config_checklist, False)