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)
18 # Mitigations of CPU vulnerabilities:
20 # mitigations=auto,nosmt (nosmt is slow)
23 # spec_store_bypass_disable=on
25 # l1d_flush=on (a part of the l1tf option)
34 # sysrq_always_enabled
39 # Hardware tag-based KASAN with arm64 Memory Tagging Extension (MTE):
41 # kasan.stacktrace=off
44 # N.B. Hardening sysctls:
45 # kernel.kptr_restrict=2 (or 1?)
46 # kernel.dmesg_restrict=1 (also see the kconfig option)
47 # kernel.perf_event_paranoid=3
48 # kernel.kexec_load_disabled=1
49 # kernel.yama.ptrace_scope=3
50 # user.max_user_namespaces=0
51 # what about bpf_jit_enable?
52 # kernel.unprivileged_bpf_disabled=1
53 # net.core.bpf_jit_harden=2
54 # vm.unprivileged_userfaultfd=0
55 # (at first, it disabled unprivileged userfaultfd,
56 # and since v5.11 it enables unprivileged userfaultfd for user-mode only)
57 # vm.mmap_min_addr has a good value
58 # dev.tty.ldisc_autoload=0
59 # fs.protected_symlinks=1
60 # fs.protected_hardlinks=1
61 # fs.protected_fifos=2
62 # fs.protected_regular=2
64 # kernel.modules_disabled=1
65 # kernel.randomize_va_space = 2
68 # pylint: disable=missing-module-docstring,missing-class-docstring,missing-function-docstring
69 # pylint: disable=line-too-long,invalid-name,too-many-branches,too-many-statements
73 from argparse import ArgumentParser
74 from collections import OrderedDict
77 from .__about__ import __version__
79 SIMPLE_OPTION_TYPES = ('kconfig', 'version', 'cmdline')
82 # Constructor without the 'expected' parameter is for option presence checks (any value is OK)
83 def __init__(self, reason, decision, name, expected=None):
84 assert(reason and decision and name), \
85 'invalid {} check for "{}"'.format(self.__class__.__name__, name)
87 self.expected = expected
88 self.decision = decision
98 # handle the option presence check
99 if self.expected is None:
100 if self.state is None:
101 self.result = 'FAIL: not present'
103 self.result = 'OK: is present'
106 # handle the option value check
107 if self.expected == self.state:
109 elif self.state is None:
110 if self.expected == 'is not set':
111 self.result = 'OK: not found'
113 self.result = 'FAIL: not found'
115 self.result = 'FAIL: "' + self.state + '"'
117 def table_print(self, _mode, with_results):
118 if self.expected is None:
121 expected = self.expected
122 print('{:<40}|{:^7}|{:^12}|{:^10}|{:^18}'.format(self.name, self.type, expected, self.decision, self.reason), end='')
124 print('| {}'.format(self.result), end='')
126 def json_dump(self, with_results):
127 dump = [self.name, self.type, self.expected, self.decision, self.reason]
129 dump.append(self.result)
133 class KconfigCheck(OptCheck):
134 def __init__(self, *args, **kwargs):
135 super().__init__(*args, **kwargs)
136 self.name = 'CONFIG_' + self.name
143 class CmdlineCheck(OptCheck):
150 def __init__(self, ver_expected):
151 self.ver_expected = ver_expected
160 if self.ver[0] > self.ver_expected[0]:
161 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
163 if self.ver[0] < self.ver_expected[0]:
164 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
166 if self.ver[1] >= self.ver_expected[1]:
167 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
169 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
171 def table_print(self, _mode, with_results):
172 ver_req = 'kernel version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
173 print('{:<91}'.format(ver_req), end='')
175 print('| {}'.format(self.result), end='')
178 class ComplexOptCheck:
179 def __init__(self, *opts):
182 'empty {} check'.format(self.__class__.__name__)
183 assert(len(self.opts) != 1), \
184 'useless {} check: {}'.format(self.__class__.__name__, opts)
185 assert(isinstance(opts[0], (KconfigCheck, CmdlineCheck))), \
186 'invalid {} check: {}'.format(self.__class__.__name__, opts)
195 return self.opts[0].name
199 return self.opts[0].expected
201 def table_print(self, mode, with_results):
202 if mode == 'verbose':
203 print(' {:87}'.format('<<< ' + self.__class__.__name__ + ' >>>'), end='')
205 print('| {}'.format(self.result), end='')
208 o.table_print(mode, with_results)
211 o.table_print(mode, False)
213 print('| {}'.format(self.result), end='')
215 def json_dump(self, with_results):
216 dump = self.opts[0].json_dump(False)
218 dump.append(self.result)
222 class OR(ComplexOptCheck):
223 # self.opts[0] is the option that this OR-check is about.
225 # OR(<X_is_hardened>, <X_is_disabled>)
226 # OR(<X_is_hardened>, <old_X_is_hardened>)
228 for i, opt in enumerate(self.opts):
230 if opt.result.startswith('OK'):
231 self.result = opt.result
232 # Add more info for additional checks:
234 if opt.result == 'OK':
235 self.result = 'OK: {} "{}"'.format(opt.name, opt.expected)
236 elif opt.result == 'OK: not found':
237 self.result = 'OK: {} not found'.format(opt.name)
238 elif opt.result == 'OK: is present':
239 self.result = 'OK: {} is present'.format(opt.name)
241 # VersionCheck provides enough info
242 assert(opt.result.startswith('OK: version')), \
243 'unexpected OK description "{}"'.format(opt.result)
245 self.result = self.opts[0].result
248 class AND(ComplexOptCheck):
249 # self.opts[0] is the option that this AND-check is about.
251 # AND(<suboption>, <main_option>)
252 # Suboption is not checked if checking of the main_option is failed.
253 # AND(<X_is_disabled>, <old_X_is_disabled>)
255 for i, opt in reversed(list(enumerate(self.opts))):
258 self.result = opt.result
260 if not opt.result.startswith('OK'):
261 # This FAIL is caused by additional checks,
262 # and not by the main option that this AND-check is about.
263 # Describe the reason of the FAIL.
264 if opt.result.startswith('FAIL: \"') or opt.result == 'FAIL: not found':
265 self.result = 'FAIL: {} not "{}"'.format(opt.name, opt.expected)
266 elif opt.result == 'FAIL: not present':
267 self.result = 'FAIL: {} not present'.format(opt.name)
269 # VersionCheck provides enough info
270 self.result = opt.result
271 assert(opt.result.startswith('FAIL: version')), \
272 'unexpected FAIL description "{}"'.format(opt.result)
276 def detect_arch(fname, archs):
277 with open(fname, 'r') as f:
278 arch_pattern = re.compile("CONFIG_[a-zA-Z0-9_]*=y")
280 for line in f.readlines():
281 if arch_pattern.match(line):
282 option, _ = line[7:].split('=', 1)
287 return None, 'more than one supported architecture is detected'
289 return None, 'failed to detect architecture'
293 def detect_version(fname):
294 with open(fname, 'r') as f:
295 ver_pattern = re.compile("# Linux/.* Kernel Configuration")
296 for line in f.readlines():
297 if ver_pattern.match(line):
301 ver_numbers = ver_str.split('.')
302 if len(ver_numbers) < 3 or not ver_numbers[0].isdigit() or not ver_numbers[1].isdigit():
303 msg = 'failed to parse the version "' + ver_str + '"'
305 return (int(ver_numbers[0]), int(ver_numbers[1])), None
306 return None, 'no kernel version detected'
309 def add_kconfig_checks(l, arch):
310 # Calling the KconfigCheck class constructor:
311 # KconfigCheck(reason, decision, name, expected)
313 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
314 # when the tool doesn't check the cmdline.
316 modules_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'MODULES', 'is not set')
317 devmem_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'DEVMEM', 'is not set') # refers to LOCKDOWN
318 bpf_syscall_not_set = KconfigCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set') # refers to LOCKDOWN
319 efi_not_set = KconfigCheck('cut_attack_surface', 'my', 'EFI', 'is not set')
321 # 'self_protection', 'defconfig'
322 l += [KconfigCheck('self_protection', 'defconfig', 'BUG', 'y')]
323 l += [KconfigCheck('self_protection', 'defconfig', 'SLUB_DEBUG', 'y')]
324 l += [KconfigCheck('self_protection', 'defconfig', 'GCC_PLUGINS', 'y')]
325 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR', 'y'),
326 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR', 'y'),
327 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_REGULAR', 'y'),
328 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_AUTO', 'y'),
329 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
330 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_STRONG', 'y'),
331 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
332 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_KERNEL_RWX', 'y'),
333 KconfigCheck('self_protection', 'defconfig', 'DEBUG_RODATA', 'y'))] # before v4.11
334 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_MODULE_RWX', 'y'),
335 KconfigCheck('self_protection', 'defconfig', 'DEBUG_SET_MODULE_RONX', 'y'),
336 modules_not_set)] # DEBUG_SET_MODULE_RONX was before v4.11
337 l += [OR(KconfigCheck('self_protection', 'defconfig', 'REFCOUNT_FULL', 'y'),
338 VersionCheck((5, 5)))] # REFCOUNT_FULL is enabled by default since v5.5
339 l += [KconfigCheck('self_protection', 'defconfig', 'THREAD_INFO_IN_TASK', 'y')]
340 iommu_support_is_set = KconfigCheck('self_protection', 'defconfig', 'IOMMU_SUPPORT', 'y')
341 l += [iommu_support_is_set] # is needed for mitigating DMA attacks
342 if arch in ('X86_64', 'ARM64', 'X86_32'):
343 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y')]
344 if arch in ('X86_64', 'ARM64'):
345 l += [KconfigCheck('self_protection', 'defconfig', 'VMAP_STACK', 'y')]
346 if arch in ('X86_64', 'X86_32'):
347 l += [KconfigCheck('self_protection', 'defconfig', 'MICROCODE', 'y')] # is needed for mitigating CPU bugs
348 l += [KconfigCheck('self_protection', 'defconfig', 'RETPOLINE', 'y')]
349 l += [KconfigCheck('self_protection', 'defconfig', 'X86_SMAP', 'y')]
350 l += [KconfigCheck('self_protection', 'defconfig', 'SYN_COOKIES', 'y')] # another reason?
351 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_UMIP', 'y'),
352 KconfigCheck('self_protection', 'defconfig', 'X86_INTEL_UMIP', 'y'))]
353 if arch in ('ARM64', 'ARM'):
354 l += [KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_PER_TASK', 'y')]
356 l += [KconfigCheck('self_protection', 'defconfig', 'PAGE_TABLE_ISOLATION', 'y')]
357 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MEMORY', 'y')]
358 l += [AND(KconfigCheck('self_protection', 'defconfig', 'INTEL_IOMMU', 'y'),
359 iommu_support_is_set)]
360 l += [AND(KconfigCheck('self_protection', 'defconfig', 'AMD_IOMMU', 'y'),
361 iommu_support_is_set)]
363 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PAN', 'y')]
364 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_EPAN', 'y')]
365 l += [KconfigCheck('self_protection', 'defconfig', 'UNMAP_KERNEL_AT_EL0', 'y')]
366 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_EL2_VECTORS', 'y'),
367 AND(KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y'),
368 VersionCheck((5, 9))))] # HARDEN_EL2_VECTORS was included in RANDOMIZE_BASE in v5.9
369 l += [KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y')]
370 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PTR_AUTH_KERNEL', 'y')]
371 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_BTI_KERNEL', 'y')]
372 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y'),
373 VersionCheck((5, 10)))] # HARDEN_BRANCH_PREDICTOR is enabled by default since v5.10
374 l += [KconfigCheck('self_protection', 'defconfig', 'MITIGATE_SPECTRE_BRANCH_HISTORY', 'y')]
375 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_MTE', 'y')]
376 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MODULE_REGION_FULL', 'y')]
378 l += [KconfigCheck('self_protection', 'defconfig', 'CPU_SW_DOMAIN_PAN', 'y')]
379 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y')]
380 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_HISTORY', 'y')]
382 # 'self_protection', 'kspp'
383 l += [KconfigCheck('self_protection', 'kspp', 'BUG_ON_DATA_CORRUPTION', 'y')]
384 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_WX', 'y')]
385 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_STACK_END_CHECK', 'y')]
386 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_HARDENED', 'y')]
387 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_RANDOM', 'y')]
388 l += [KconfigCheck('self_protection', 'kspp', 'SHUFFLE_PAGE_ALLOCATOR', 'y')]
389 l += [KconfigCheck('self_protection', 'kspp', 'FORTIFY_SOURCE', 'y')]
390 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_LIST', 'y')]
391 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_SG', 'y')]
392 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_CREDENTIALS', 'y')]
393 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_NOTIFIERS', 'y')]
394 l += [KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y')]
395 l += [KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_LATENT_ENTROPY', 'y')]
396 l += [KconfigCheck('self_protection', 'kspp', 'KFENCE', 'y')]
397 l += [KconfigCheck('self_protection', 'kspp', 'WERROR', 'y')]
398 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y')]
399 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set')] # true if IOMMU_DEFAULT_DMA_STRICT is set
400 l += [KconfigCheck('self_protection', 'kspp', 'ZERO_CALL_USED_REGS', 'y')]
401 randstruct_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT', 'y')
402 l += [randstruct_is_set]
403 hardened_usercopy_is_set = KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y')
404 l += [hardened_usercopy_is_set]
405 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
406 hardened_usercopy_is_set)]
407 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_PAGESPAN', 'is not set'),
408 hardened_usercopy_is_set)]
409 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG', 'y'),
411 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_ALL', 'y'),
413 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_SHA512', 'y'),
415 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_FORCE', 'y'),
416 modules_not_set)] # refers to LOCKDOWN
417 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_STACK_ALL_ZERO', 'y'),
418 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y'))]
419 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
420 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'))]
421 # CONFIG_INIT_ON_FREE_DEFAULT_ON was added in v5.3.
422 # CONFIG_PAGE_POISONING_ZERO was removed in v5.11.
423 # Starting from v5.11 CONFIG_PAGE_POISONING unconditionally checks
424 # the 0xAA poison pattern on allocation.
425 # That brings higher performance penalty.
426 if arch in ('X86_64', 'ARM64', 'X86_32'):
427 stackleak_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STACKLEAK', 'y')
428 l += [stackleak_is_set]
429 l += [KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y')]
430 if arch in ('X86_64', 'X86_32'):
431 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_CORE', 'y')]
432 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '65536')]
433 if arch in ('ARM64', 'ARM'):
434 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '32768')]
435 l += [KconfigCheck('self_protection', 'kspp', 'SYN_COOKIES', 'y')] # another reason?
437 l += [KconfigCheck('self_protection', 'kspp', 'ARM64_SW_TTBR0_PAN', 'y')]
439 l += [KconfigCheck('self_protection', 'kspp', 'PAGE_TABLE_ISOLATION', 'y')]
440 l += [KconfigCheck('self_protection', 'kspp', 'HIGHMEM64G', 'y')]
441 l += [KconfigCheck('self_protection', 'kspp', 'X86_PAE', 'y')]
443 # 'self_protection', 'maintainer'
444 ubsan_bounds_is_set = KconfigCheck('self_protection', 'maintainer', 'UBSAN_BOUNDS', 'y') # only array index bounds checking
445 l += [ubsan_bounds_is_set] # recommended by Kees Cook in /issues/53
446 if arch in ('X86_64', 'ARM64', 'X86_32'): # ARCH_HAS_UBSAN_SANITIZE_ALL is not enabled for ARM
447 l += [AND(KconfigCheck('self_protection', 'maintainer', 'UBSAN_SANITIZE_ALL', 'y'),
448 ubsan_bounds_is_set)] # recommended by Kees Cook in /issues/53
449 l += [AND(KconfigCheck('self_protection', 'maintainer', 'UBSAN_TRAP', 'y'),
450 ubsan_bounds_is_set)] # recommended by Kees Cook in /issues/53
452 # 'self_protection', 'clipos'
453 l += [KconfigCheck('self_protection', 'clipos', 'DEBUG_VIRTUAL', 'y')]
454 l += [KconfigCheck('self_protection', 'clipos', 'STATIC_USERMODEHELPER', 'y')] # needs userspace support
455 l += [OR(KconfigCheck('self_protection', 'clipos', 'EFI_DISABLE_PCI_DMA', 'y'),
457 l += [KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set')]
458 l += [KconfigCheck('self_protection', 'clipos', 'RANDOM_TRUST_BOOTLOADER', 'is not set')]
459 l += [KconfigCheck('self_protection', 'clipos', 'RANDOM_TRUST_CPU', 'is not set')]
460 l += [AND(KconfigCheck('self_protection', 'clipos', 'GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set'),
462 if arch in ('X86_64', 'ARM64', 'X86_32'):
463 l += [AND(KconfigCheck('self_protection', 'clipos', 'STACKLEAK_METRICS', 'is not set'),
465 l += [AND(KconfigCheck('self_protection', 'clipos', 'STACKLEAK_RUNTIME_DISABLE', 'is not set'),
467 if arch in ('X86_64', 'X86_32'):
468 l += [AND(KconfigCheck('self_protection', 'clipos', 'INTEL_IOMMU_DEFAULT_ON', 'y'),
469 iommu_support_is_set)]
471 l += [AND(KconfigCheck('self_protection', 'clipos', 'INTEL_IOMMU_SVM', 'y'),
472 iommu_support_is_set)]
474 l += [AND(KconfigCheck('self_protection', 'clipos', 'INTEL_IOMMU', 'y'),
475 iommu_support_is_set)]
477 # 'self_protection', 'my'
478 l += [OR(KconfigCheck('self_protection', 'my', 'RESET_ATTACK_MITIGATION', 'y'),
479 efi_not_set)] # needs userspace support (systemd)
481 l += [KconfigCheck('self_protection', 'my', 'SLS', 'y')] # vs CVE-2021-26341 in Straight-Line-Speculation
482 l += [AND(KconfigCheck('self_protection', 'my', 'AMD_IOMMU_V2', 'y'),
483 iommu_support_is_set)]
485 l += [KconfigCheck('self_protection', 'my', 'SHADOW_CALL_STACK', 'y')] # depends on clang, maybe it's alternative to STACKPROTECTOR_STRONG
486 l += [KconfigCheck('self_protection', 'my', 'KASAN_HW_TAGS', 'y')]
487 cfi_clang_is_set = KconfigCheck('self_protection', 'my', 'CFI_CLANG', 'y')
488 l += [cfi_clang_is_set]
489 l += [AND(KconfigCheck('self_protection', 'my', 'CFI_PERMISSIVE', 'is not set'),
493 if arch in ('X86_64', 'ARM64', 'X86_32'):
494 l += [KconfigCheck('security_policy', 'defconfig', 'SECURITY', 'y')] # and choose your favourite LSM
496 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY', 'y')] # and choose your favourite LSM
497 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_YAMA', 'y')]
498 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DISABLE', 'is not set')]
499 l += [KconfigCheck('security_policy', 'clipos', 'SECURITY_LOCKDOWN_LSM', 'y')]
500 l += [KconfigCheck('security_policy', 'clipos', 'SECURITY_LOCKDOWN_LSM_EARLY', 'y')]
501 l += [KconfigCheck('security_policy', 'clipos', 'LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y')]
502 l += [KconfigCheck('security_policy', 'my', 'SECURITY_WRITABLE_HOOKS', 'is not set')] # refers to SECURITY_SELINUX_DISABLE
503 l += [KconfigCheck('security_policy', 'my', 'SECURITY_SAFESETID', 'y')]
504 loadpin_is_set = KconfigCheck('security_policy', 'my', 'SECURITY_LOADPIN', 'y')
505 l += [loadpin_is_set] # needs userspace support
506 l += [AND(KconfigCheck('security_policy', 'my', 'SECURITY_LOADPIN_ENFORCE', 'y'),
509 # 'cut_attack_surface', 'defconfig'
510 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'BPF_UNPRIV_DEFAULT_OFF', 'y'),
511 bpf_syscall_not_set)] # see unprivileged_bpf_disabled
512 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP', 'y')]
513 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP_FILTER', 'y')]
514 if arch in ('X86_64', 'ARM64', 'X86_32'):
515 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'STRICT_DEVMEM', 'y'),
516 devmem_not_set)] # refers to LOCKDOWN
518 # 'cut_attack_surface', 'kspp'
519 l += [KconfigCheck('cut_attack_surface', 'kspp', 'SECURITY_DMESG_RESTRICT', 'y')]
520 l += [KconfigCheck('cut_attack_surface', 'kspp', 'ACPI_CUSTOM_METHOD', 'is not set')] # refers to LOCKDOWN
521 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_BRK', 'is not set')]
522 l += [KconfigCheck('cut_attack_surface', 'kspp', 'DEVKMEM', 'is not set')] # refers to LOCKDOWN
523 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_VDSO', 'is not set')]
524 l += [KconfigCheck('cut_attack_surface', 'kspp', 'BINFMT_MISC', 'is not set')]
525 l += [KconfigCheck('cut_attack_surface', 'kspp', 'INET_DIAG', 'is not set')]
526 l += [KconfigCheck('cut_attack_surface', 'kspp', 'KEXEC', 'is not set')] # refers to LOCKDOWN
527 l += [KconfigCheck('cut_attack_surface', 'kspp', 'PROC_KCORE', 'is not set')] # refers to LOCKDOWN
528 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_PTYS', 'is not set')]
529 l += [KconfigCheck('cut_attack_surface', 'kspp', 'HIBERNATION', 'is not set')] # refers to LOCKDOWN
530 l += [KconfigCheck('cut_attack_surface', 'kspp', 'IA32_EMULATION', 'is not set')]
531 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_X32', 'is not set')]
532 l += [KconfigCheck('cut_attack_surface', 'kspp', 'MODIFY_LDT_SYSCALL', 'is not set')]
533 l += [KconfigCheck('cut_attack_surface', 'kspp', 'OABI_COMPAT', 'is not set')]
534 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_MSR', 'is not set')] # refers to LOCKDOWN
535 l += [modules_not_set]
536 l += [devmem_not_set]
537 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'IO_STRICT_DEVMEM', 'y'),
538 devmem_not_set)] # refers to LOCKDOWN
540 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'STRICT_DEVMEM', 'y'),
541 devmem_not_set)] # refers to LOCKDOWN
543 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y')] # 'vsyscall=none'
545 # 'cut_attack_surface', 'grsec'
546 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ZSMALLOC_STAT', 'is not set')]
547 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PAGE_OWNER', 'is not set')]
548 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_KMEMLEAK', 'is not set')]
549 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BINFMT_AOUT', 'is not set')]
550 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KPROBE_EVENTS', 'is not set')]
551 l += [KconfigCheck('cut_attack_surface', 'grsec', 'UPROBE_EVENTS', 'is not set')]
552 l += [KconfigCheck('cut_attack_surface', 'grsec', 'GENERIC_TRACER', 'is not set')] # refers to LOCKDOWN
553 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FUNCTION_TRACER', 'is not set')]
554 l += [KconfigCheck('cut_attack_surface', 'grsec', 'STACK_TRACER', 'is not set')]
555 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HIST_TRIGGERS', 'is not set')]
556 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BLK_DEV_IO_TRACE', 'is not set')]
557 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_VMCORE', 'is not set')]
558 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_PAGE_MONITOR', 'is not set')]
559 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USELIB', 'is not set')]
560 l += [KconfigCheck('cut_attack_surface', 'grsec', 'CHECKPOINT_RESTORE', 'is not set')]
561 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USERFAULTFD', 'is not set')]
562 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HWPOISON_INJECT', 'is not set')]
563 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MEM_SOFT_DIRTY', 'is not set')]
564 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEVPORT', 'is not set')] # refers to LOCKDOWN
565 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set')] # refers to LOCKDOWN
566 l += [KconfigCheck('cut_attack_surface', 'grsec', 'NOTIFIER_ERROR_INJECTION', 'is not set')]
567 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FAIL_FUTEX', 'is not set')]
568 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PUNIT_ATOM_DEBUG', 'is not set')]
569 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ACPI_CONFIGFS', 'is not set')]
570 l += [KconfigCheck('cut_attack_surface', 'grsec', 'EDAC_DEBUG', 'is not set')]
571 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DRM_I915_DEBUG', 'is not set')]
572 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BCACHE_CLOSURES_DEBUG', 'is not set')]
573 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DVB_C8SECTPFE', 'is not set')]
574 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_SLRAM', 'is not set')]
575 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_PHRAM', 'is not set')]
576 l += [KconfigCheck('cut_attack_surface', 'grsec', 'IO_URING', 'is not set')]
577 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCMP', 'is not set')]
578 l += [KconfigCheck('cut_attack_surface', 'grsec', 'RSEQ', 'is not set')]
579 l += [KconfigCheck('cut_attack_surface', 'grsec', 'LATENCYTOP', 'is not set')]
580 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCOV', 'is not set')]
581 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROVIDE_OHCI1394_DMA_INIT', 'is not set')]
582 l += [KconfigCheck('cut_attack_surface', 'grsec', 'SUNRPC_DEBUG', 'is not set')]
583 l += [AND(KconfigCheck('cut_attack_surface', 'grsec', 'PTDUMP_DEBUGFS', 'is not set'),
584 KconfigCheck('cut_attack_surface', 'grsec', 'X86_PTDUMP', 'is not set'))]
586 # 'cut_attack_surface', 'maintainer'
587 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'DRM_LEGACY', 'is not set')] # recommended by Daniel Vetter in /issues/38
588 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'FB', 'is not set')] # recommended by Daniel Vetter in /issues/38
589 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'VT', 'is not set')] # recommended by Daniel Vetter in /issues/38
590 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD', 'is not set')] # recommended by Denis Efremov in /pull/54
591 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD_RAWCMD', 'is not set')] # recommended by Denis Efremov in /pull/62
593 # 'cut_attack_surface', 'grapheneos'
594 l += [KconfigCheck('cut_attack_surface', 'grapheneos', 'AIO', 'is not set')]
596 # 'cut_attack_surface', 'clipos'
597 l += [KconfigCheck('cut_attack_surface', 'clipos', 'STAGING', 'is not set')]
598 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KSM', 'is not set')] # to prevent FLUSH+RELOAD attack
599 # l += [KconfigCheck('cut_attack_surface', 'clipos', 'IKCONFIG', 'is not set')] # no, IKCONFIG is needed for this check :)
600 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KALLSYMS', 'is not set')]
601 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_VSYSCALL_EMULATION', 'is not set')]
602 l += [KconfigCheck('cut_attack_surface', 'clipos', 'MAGIC_SYSRQ', 'is not set')]
603 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KEXEC_FILE', 'is not set')] # refers to LOCKDOWN (permissive)
604 l += [KconfigCheck('cut_attack_surface', 'clipos', 'USER_NS', 'is not set')] # user.max_user_namespaces=0
605 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_CPUID', 'is not set')]
606 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_IOPL_IOPERM', 'is not set')] # refers to LOCKDOWN
607 l += [KconfigCheck('cut_attack_surface', 'clipos', 'ACPI_TABLE_UPGRADE', 'is not set')] # refers to LOCKDOWN
608 l += [KconfigCheck('cut_attack_surface', 'clipos', 'EFI_CUSTOM_SSDT_OVERLAYS', 'is not set')]
609 l += [AND(KconfigCheck('cut_attack_surface', 'clipos', 'LDISC_AUTOLOAD', 'is not set'),
610 KconfigCheck('cut_attack_surface', 'clipos', 'LDISC_AUTOLOAD'))] # option presence check
611 if arch in ('X86_64', 'X86_32'):
612 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_INTEL_TSX_MODE_OFF', 'y')] # tsx=off
614 # 'cut_attack_surface', 'lockdown'
615 l += [bpf_syscall_not_set] # refers to LOCKDOWN
616 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'EFI_TEST', 'is not set')] # refers to LOCKDOWN
617 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'MMIOTRACE_TEST', 'is not set')] # refers to LOCKDOWN
618 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'KPROBES', 'is not set')] # refers to LOCKDOWN
620 # 'cut_attack_surface', 'my'
621 l += [OR(KconfigCheck('cut_attack_surface', 'my', 'TRIM_UNUSED_KSYMS', 'y'),
623 l += [KconfigCheck('cut_attack_surface', 'my', 'MMIOTRACE', 'is not set')] # refers to LOCKDOWN (permissive)
624 l += [KconfigCheck('cut_attack_surface', 'my', 'LIVEPATCH', 'is not set')]
625 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_DCCP', 'is not set')]
626 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_SCTP', 'is not set')]
627 l += [KconfigCheck('cut_attack_surface', 'my', 'FTRACE', 'is not set')] # refers to LOCKDOWN
628 l += [KconfigCheck('cut_attack_surface', 'my', 'VIDEO_VIVID', 'is not set')]
629 l += [KconfigCheck('cut_attack_surface', 'my', 'INPUT_EVBUG', 'is not set')] # Can be used as a keylogger
630 l += [KconfigCheck('cut_attack_surface', 'my', 'KGDB', 'is not set')]
633 if arch in ('X86_64', 'ARM64', 'X86_32'):
634 l += [KconfigCheck('harden_userspace', 'defconfig', 'INTEGRITY', 'y')]
636 l += [KconfigCheck('harden_userspace', 'my', 'INTEGRITY', 'y')]
638 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_PTR_AUTH', 'y')]
639 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_BTI', 'y')]
640 if arch in ('ARM', 'X86_32'):
641 l += [KconfigCheck('harden_userspace', 'defconfig', 'VMSPLIT_3G', 'y')]
642 if arch in ('X86_64', 'ARM64'):
643 l += [KconfigCheck('harden_userspace', 'clipos', 'ARCH_MMAP_RND_BITS', '32')]
644 if arch in ('X86_32', 'ARM'):
645 l += [KconfigCheck('harden_userspace', 'my', 'ARCH_MMAP_RND_BITS', '16')]
648 def add_cmdline_checks(l, arch):
649 # Calling the CmdlineCheck class constructor:
650 # CmdlineCheck(reason, decision, name, expected)
652 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
653 # when the tool doesn't check the cmdline.
655 # [!] Make sure that values of the options in CmdlineChecks need normalization.
656 # For more info see normalize_cmdline_options().
658 # A common pattern for checking the 'param_x' cmdline parameter
659 # that __overrides__ the 'PARAM_X_DEFAULT' kconfig option:
660 # l += [OR(CmdlineCheck(reason, decision, 'param_x', '1'),
661 # AND(KconfigCheck(reason, decision, 'PARAM_X_DEFAULT_ON', 'y'),
662 # CmdlineCheck(reason, decision, 'param_x, 'is not set')))]
664 # Here we don't check the kconfig options or minimal kernel version
665 # required for the cmdline parameters. That would make the checks
666 # very complex and not give a 100% guarantee anyway.
668 # 'self_protection', 'defconfig'
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 # 'self_protection', 'kspp'
678 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', '1'),
679 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y'),
680 CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', 'is not set')))]
681 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_free', '1'),
682 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
683 CmdlineCheck('self_protection', 'kspp', 'init_on_free', 'is not set')),
684 AND(CmdlineCheck('self_protection', 'kspp', 'page_poison', '1'),
685 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'),
686 CmdlineCheck('self_protection', 'kspp', 'slub_debug', 'P')))]
687 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_nomerge'),
688 AND(KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set'),
689 CmdlineCheck('self_protection', 'kspp', 'slab_merge', 'is not set')))] # option presence check
690 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.strict', '1'),
691 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y'),
692 CmdlineCheck('self_protection', 'kspp', 'iommu.strict', 'is not set')))]
693 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', '0'),
694 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set'),
695 CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', 'is not set')))]
696 # The cmdline checks compatible with the kconfig recommendations of the KSPP project...
697 l += [OR(CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', '1'),
698 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y'),
699 CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', 'is not set')))]
700 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', '0'),
701 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
702 CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', 'is not set')))]
703 l += [OR(CmdlineCheck('self_protection', 'kspp', 'page_alloc.shuffle', '1'),
704 AND(KconfigCheck('self_protection', 'kspp', 'SHUFFLE_PAGE_ALLOCATOR', 'y'),
705 CmdlineCheck('self_protection', 'kspp', 'page_alloc.shuffle', 'is not set')))] # ... the end
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')]
713 # 'cut_attack_surface', 'kspp'
715 l += [OR(CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'none'),
716 AND(KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y'),
717 CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'is not set')))]
719 # 'cut_attack_surface', 'grsec'
720 # The cmdline checks compatible with the kconfig options disabled by grsecurity...
721 l += [OR(CmdlineCheck('cut_attack_surface', 'grsec', 'debugfs', 'off'),
722 KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set'))] # ... the end
725 def print_unknown_options(checklist, parsed_options):
729 if o1.type != 'complex':
730 known_options.append(o1.name)
733 if o2.type != 'complex':
734 if hasattr(o2, 'name'):
735 known_options.append(o2.name)
738 assert(o3.type != 'complex'), \
739 'unexpected ComplexOptCheck inside {}'.format(o2.name)
740 if hasattr(o3, 'name'):
741 known_options.append(o3.name)
743 for option, value in parsed_options.items():
744 if option not in known_options:
745 print('[?] No check for option {} ({})'.format(option, value))
748 def print_checklist(mode, checklist, with_results):
752 output.append(o.json_dump(with_results))
753 print(json.dumps(output))
760 print('=' * sep_line_len)
761 print('{:^40}|{:^7}|{:^12}|{:^10}|{:^18}'.format('option name', 'type', 'desired val', 'decision', 'reason'), end='')
763 print('| {}'.format('check result'), end='')
765 print('=' * sep_line_len)
768 for opt in checklist:
770 if mode == 'show_ok':
771 if not opt.result.startswith('OK'):
773 if mode == 'show_fail':
774 if not opt.result.startswith('FAIL'):
776 opt.table_print(mode, with_results)
778 if mode == 'verbose':
779 print('-' * sep_line_len)
784 fail_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), checklist)))
786 ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), checklist)))
788 if mode == 'show_ok':
789 fail_suppressed = ' (suppressed in output)'
790 if mode == 'show_fail':
791 ok_suppressed = ' (suppressed in output)'
793 print('[+] Config check is finished: \'OK\' - {}{} / \'FAIL\' - {}{}'.format(ok_count, ok_suppressed, fail_count, fail_suppressed))
796 def populate_simple_opt_with_data(opt, data, data_type):
797 assert(opt.type != 'complex'), \
798 'unexpected ComplexOptCheck "{}"'.format(opt.name)
799 assert(opt.type in SIMPLE_OPTION_TYPES), \
800 'invalid opt type "{}"'.format(opt.type)
801 assert(data_type in SIMPLE_OPTION_TYPES), \
802 'invalid data type "{}"'.format(data_type)
804 if data_type != opt.type:
807 if data_type in ('kconfig', 'cmdline'):
808 opt.state = data.get(opt.name, None)
810 assert(data_type == 'version'), \
811 'unexpected data type "{}"'.format(data_type)
815 def populate_opt_with_data(opt, data, data_type):
816 if opt.type == 'complex':
818 if o.type == 'complex':
819 # Recursion for nested ComplexOptCheck objects
820 populate_opt_with_data(o, data, data_type)
822 populate_simple_opt_with_data(o, data, data_type)
824 assert(opt.type in ('kconfig', 'cmdline')), \
825 'bad type "{}" for a simple check'.format(opt.type)
826 populate_simple_opt_with_data(opt, data, data_type)
829 def populate_with_data(checklist, data, data_type):
830 for opt in checklist:
831 populate_opt_with_data(opt, data, data_type)
834 def perform_checks(checklist):
835 for opt in checklist:
839 def parse_kconfig_file(parsed_options, fname):
840 with open(fname, 'r') as f:
841 opt_is_on = re.compile("CONFIG_[a-zA-Z0-9_]*=[a-zA-Z0-9_\"]*")
842 opt_is_off = re.compile("# CONFIG_[a-zA-Z0-9_]* is not set")
844 for line in f.readlines():
849 if opt_is_on.match(line):
850 option, value = line.split('=', 1)
851 if value == 'is not set':
852 sys.exit('[!] ERROR: bad enabled kconfig option "{}"'.format(line))
853 elif opt_is_off.match(line):
854 option, value = line[2:].split(' ', 1)
855 if value != 'is not set':
856 sys.exit('[!] ERROR: bad disabled kconfig option "{}"'.format(line))
858 if option in parsed_options:
859 sys.exit('[!] ERROR: kconfig option "{}" exists multiple times'.format(line))
862 parsed_options[option] = value
865 def normalize_cmdline_options(option, value):
866 # Don't normalize the cmdline option values if
867 # the Linux kernel doesn't use kstrtobool() for them
869 # See pti_check_boottime_disable() in linux/arch/x86/mm/pti.c
871 if option == 'debugfs':
872 # See debugfs_kernel() in fs/debugfs/inode.c
875 # Implement a limited part of the kstrtobool() logic
876 if value in ('1', 'on', 'On', 'ON', 'y', 'Y', 'yes', 'Yes', 'YES'):
878 if value in ('0', 'off', 'Off', 'OFF', 'n', 'N', 'no', 'No', 'NO'):
881 # Preserve unique values
885 def parse_cmdline_file(parsed_options, fname):
886 with open(fname, 'r') as f:
892 sys.exit('[!] ERROR: more than one line in "{}"'.format(fname))
896 name, value = opt.split('=', 1)
899 value = '' # '' is not None
900 value = normalize_cmdline_options(name, value)
901 parsed_options[name] = value
907 # - reporting about unknown kernel options in the kconfig
908 # - verbose printing of ComplexOptCheck items
909 # * json mode for printing the results in JSON format
910 report_modes = ['verbose', 'json', 'show_ok', 'show_fail']
911 supported_archs = ['X86_64', 'X86_32', 'ARM64', 'ARM']
912 parser = ArgumentParser(prog='kconfig-hardened-check',
913 description='A tool for checking the security hardening options of the Linux kernel')
914 parser.add_argument('--version', action='version', version='%(prog)s ' + __version__)
915 parser.add_argument('-p', '--print', choices=supported_archs,
916 help='print security hardening preferences for the selected architecture')
917 parser.add_argument('-c', '--config',
918 help='check the kernel kconfig file against these preferences')
919 parser.add_argument('-l', '--cmdline',
920 help='check the kernel cmdline file against these preferences')
921 parser.add_argument('-m', '--mode', choices=report_modes,
922 help='choose the report mode')
923 args = parser.parse_args()
929 print('[+] Special report mode: {}'.format(mode))
931 config_checklist = []
935 sys.exit('[!] ERROR: --config and --print can\'t be used together')
938 print('[+] Kconfig file to check: {}'.format(args.config))
940 print('[+] Kernel cmdline file to check: {}'.format(args.cmdline))
942 arch, msg = detect_arch(args.config, supported_archs)
944 sys.exit('[!] ERROR: {}'.format(msg))
946 print('[+] Detected architecture: {}'.format(arch))
948 kernel_version, msg = detect_version(args.config)
949 if not kernel_version:
950 sys.exit('[!] ERROR: {}'.format(msg))
952 print('[+] Detected kernel version: {}.{}'.format(kernel_version[0], kernel_version[1]))
954 # add relevant kconfig checks to the checklist
955 add_kconfig_checks(config_checklist, arch)
958 # add relevant cmdline checks to the checklist
959 add_cmdline_checks(config_checklist, arch)
961 # populate the checklist with the parsed kconfig data
962 parsed_kconfig_options = OrderedDict()
963 parse_kconfig_file(parsed_kconfig_options, args.config)
964 populate_with_data(config_checklist, parsed_kconfig_options, 'kconfig')
965 populate_with_data(config_checklist, kernel_version, 'version')
968 # populate the checklist with the parsed kconfig data
969 parsed_cmdline_options = OrderedDict()
970 parse_cmdline_file(parsed_cmdline_options, args.cmdline)
971 populate_with_data(config_checklist, parsed_cmdline_options, 'cmdline')
973 # now everything is ready for performing the checks
974 perform_checks(config_checklist)
976 # finally print the results
977 if mode == 'verbose':
978 print_unknown_options(config_checklist, parsed_kconfig_options)
979 print_checklist(mode, config_checklist, True)
983 sys.exit('[!] ERROR: checking cmdline doesn\'t work without checking kconfig')
986 if mode in ('show_ok', 'show_fail'):
987 sys.exit('[!] ERROR: wrong mode "{}" for --print'.format(mode))
989 add_kconfig_checks(config_checklist, arch)
990 add_cmdline_checks(config_checklist, arch)
992 print('[+] Printing kernel security hardening preferences for {}...'.format(arch))
993 print_checklist(mode, config_checklist, False)