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_kernel_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 detect_compiler(fname):
310 with open(fname, 'r') as f:
311 gcc_version_pattern = re.compile("CONFIG_GCC_VERSION=[0-9]*")
312 clang_version_pattern = re.compile("CONFIG_CLANG_VERSION=[0-9]*")
313 for line in f.readlines():
314 if gcc_version_pattern.match(line):
315 gcc_version = line[19:-1]
316 if clang_version_pattern.match(line):
317 clang_version = line[21:-1]
318 if not gcc_version or not clang_version:
319 return None, 'no CONFIG_GCC_VERSION or CONFIG_CLANG_VERSION'
320 if gcc_version == '0' and clang_version != '0':
321 return 'CLANG ' + clang_version, 'OK'
322 if gcc_version != '0' and clang_version == '0':
323 return 'GCC ' + gcc_version, 'OK'
324 sys.exit('[!] ERROR: invalid GCC_VERSION and CLANG_VERSION: {} {}'.format(gcc_version, clang_version))
327 def add_kconfig_checks(l, arch):
328 # Calling the KconfigCheck class constructor:
329 # KconfigCheck(reason, decision, name, expected)
331 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
332 # when the tool doesn't check the cmdline.
334 efi_not_set = KconfigCheck('-', '-', 'EFI', 'is not set')
335 cc_is_gcc = KconfigCheck('-', '-', 'CC_IS_GCC', 'y')
336 cc_is_clang = KconfigCheck('-', '-', 'CC_IS_CLANG', 'y')
338 modules_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'MODULES', 'is not set')
339 devmem_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'DEVMEM', 'is not set') # refers to LOCKDOWN
340 bpf_syscall_not_set = KconfigCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set') # refers to LOCKDOWN
342 # 'self_protection', 'defconfig'
343 l += [KconfigCheck('self_protection', 'defconfig', 'BUG', 'y')]
344 l += [KconfigCheck('self_protection', 'defconfig', 'SLUB_DEBUG', 'y')]
345 gcc_plugins_support_is_set = KconfigCheck('self_protection', 'defconfig', 'GCC_PLUGINS', 'y')
346 l += [gcc_plugins_support_is_set]
347 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR', 'y'),
348 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR', 'y'),
349 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_REGULAR', 'y'),
350 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_AUTO', 'y'),
351 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
352 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_STRONG', 'y'),
353 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
354 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_KERNEL_RWX', 'y'),
355 KconfigCheck('self_protection', 'defconfig', 'DEBUG_RODATA', 'y'))] # before v4.11
356 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_MODULE_RWX', 'y'),
357 KconfigCheck('self_protection', 'defconfig', 'DEBUG_SET_MODULE_RONX', 'y'),
358 modules_not_set)] # DEBUG_SET_MODULE_RONX was before v4.11
359 l += [OR(KconfigCheck('self_protection', 'defconfig', 'REFCOUNT_FULL', 'y'),
360 VersionCheck((5, 5)))] # REFCOUNT_FULL is enabled by default since v5.5
361 l += [KconfigCheck('self_protection', 'defconfig', 'THREAD_INFO_IN_TASK', 'y')]
362 iommu_support_is_set = KconfigCheck('self_protection', 'defconfig', 'IOMMU_SUPPORT', 'y')
363 l += [iommu_support_is_set] # is needed for mitigating DMA attacks
364 if arch in ('X86_64', 'ARM64', 'X86_32'):
365 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y')]
366 if arch in ('X86_64', 'ARM64'):
367 l += [KconfigCheck('self_protection', 'defconfig', 'VMAP_STACK', 'y')]
368 if arch in ('X86_64', 'X86_32'):
369 l += [KconfigCheck('self_protection', 'defconfig', 'MICROCODE', 'y')] # is needed for mitigating CPU bugs
370 l += [KconfigCheck('self_protection', 'defconfig', 'RETPOLINE', 'y')]
371 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_SMAP', 'y'),
372 VersionCheck((5, 19)))] # X86_SMAP is enabled by default since v5.19
373 l += [KconfigCheck('self_protection', 'defconfig', 'SYN_COOKIES', 'y')] # another reason?
374 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_UMIP', 'y'),
375 KconfigCheck('self_protection', 'defconfig', 'X86_INTEL_UMIP', 'y'))]
376 if arch in ('ARM64', 'ARM'):
377 l += [KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_PER_TASK', 'y')]
379 l += [KconfigCheck('self_protection', 'defconfig', 'PAGE_TABLE_ISOLATION', 'y')]
380 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MEMORY', 'y')]
381 l += [AND(KconfigCheck('self_protection', 'defconfig', 'INTEL_IOMMU', 'y'),
382 iommu_support_is_set)]
383 l += [AND(KconfigCheck('self_protection', 'defconfig', 'AMD_IOMMU', 'y'),
384 iommu_support_is_set)]
386 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PAN', 'y')]
387 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_EPAN', 'y')]
388 l += [KconfigCheck('self_protection', 'defconfig', 'UNMAP_KERNEL_AT_EL0', 'y')]
389 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_EL2_VECTORS', 'y'),
390 AND(KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y'),
391 VersionCheck((5, 9))))] # HARDEN_EL2_VECTORS was included in RANDOMIZE_BASE in v5.9
392 l += [KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y')]
393 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PTR_AUTH_KERNEL', 'y')]
394 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_BTI_KERNEL', 'y')]
395 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y'),
396 VersionCheck((5, 10)))] # HARDEN_BRANCH_PREDICTOR is enabled by default since v5.10
397 l += [KconfigCheck('self_protection', 'defconfig', 'MITIGATE_SPECTRE_BRANCH_HISTORY', 'y')]
398 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_MTE', 'y')]
399 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MODULE_REGION_FULL', 'y')]
401 l += [KconfigCheck('self_protection', 'defconfig', 'CPU_SW_DOMAIN_PAN', 'y')]
402 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y')]
403 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_HISTORY', 'y')]
405 # 'self_protection', 'kspp'
406 l += [KconfigCheck('self_protection', 'kspp', 'BUG_ON_DATA_CORRUPTION', 'y')]
407 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_WX', 'y')]
408 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_STACK_END_CHECK', 'y')]
409 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_HARDENED', 'y')]
410 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_RANDOM', 'y')]
411 l += [KconfigCheck('self_protection', 'kspp', 'SHUFFLE_PAGE_ALLOCATOR', 'y')]
412 l += [KconfigCheck('self_protection', 'kspp', 'FORTIFY_SOURCE', 'y')]
413 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_LIST', 'y')]
414 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_SG', 'y')]
415 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_CREDENTIALS', 'y')]
416 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_NOTIFIERS', 'y')]
417 l += [KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y')]
418 l += [AND(KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_LATENT_ENTROPY', 'y'),
419 gcc_plugins_support_is_set)]
420 l += [KconfigCheck('self_protection', 'kspp', 'KFENCE', 'y')]
421 l += [KconfigCheck('self_protection', 'kspp', 'WERROR', 'y')]
422 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y')]
423 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set')] # true if IOMMU_DEFAULT_DMA_STRICT is set
424 l += [KconfigCheck('self_protection', 'kspp', 'ZERO_CALL_USED_REGS', 'y')]
425 randstruct_is_set = OR(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_FULL', 'y'),
426 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT', 'y'))
427 l += [randstruct_is_set]
428 hardened_usercopy_is_set = KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y')
429 l += [hardened_usercopy_is_set]
430 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
431 hardened_usercopy_is_set)]
432 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_PAGESPAN', 'is not set'),
433 hardened_usercopy_is_set)]
434 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG', 'y'),
436 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_ALL', 'y'),
438 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_SHA512', 'y'),
440 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_FORCE', 'y'),
441 modules_not_set)] # refers to LOCKDOWN
442 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_STACK_ALL_ZERO', 'y'),
443 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y'))]
444 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
445 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'))]
446 # CONFIG_INIT_ON_FREE_DEFAULT_ON was added in v5.3.
447 # CONFIG_PAGE_POISONING_ZERO was removed in v5.11.
448 # Starting from v5.11 CONFIG_PAGE_POISONING unconditionally checks
449 # the 0xAA poison pattern on allocation.
450 # That brings higher performance penalty.
451 if arch in ('X86_64', 'ARM64', 'X86_32'):
452 stackleak_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STACKLEAK', 'y')
453 l += [AND(stackleak_is_set, gcc_plugins_support_is_set)]
454 l += [KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y')]
455 if arch in ('X86_64', 'X86_32'):
456 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_CORE', 'y')]
457 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '65536')]
458 if arch in ('ARM64', 'ARM'):
459 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '32768')]
460 l += [KconfigCheck('self_protection', 'kspp', 'SYN_COOKIES', 'y')] # another reason?
462 l += [KconfigCheck('self_protection', 'kspp', 'ARM64_SW_TTBR0_PAN', 'y')]
464 l += [KconfigCheck('self_protection', 'kspp', 'PAGE_TABLE_ISOLATION', 'y')]
465 l += [KconfigCheck('self_protection', 'kspp', 'HIGHMEM64G', 'y')]
466 l += [KconfigCheck('self_protection', 'kspp', 'X86_PAE', 'y')]
468 # 'self_protection', 'maintainer'
469 ubsan_bounds_is_set = KconfigCheck('self_protection', 'maintainer', 'UBSAN_BOUNDS', 'y') # only array index bounds checking
470 l += [ubsan_bounds_is_set] # recommended by Kees Cook in /issues/53
471 if arch in ('X86_64', 'ARM64', 'X86_32'): # ARCH_HAS_UBSAN_SANITIZE_ALL is not enabled for ARM
472 l += [AND(KconfigCheck('self_protection', 'maintainer', 'UBSAN_SANITIZE_ALL', 'y'),
473 ubsan_bounds_is_set)] # recommended by Kees Cook in /issues/53
474 l += [AND(KconfigCheck('self_protection', 'maintainer', 'UBSAN_TRAP', 'y'),
475 ubsan_bounds_is_set)] # recommended by Kees Cook in /issues/53
477 # 'self_protection', 'clipos'
478 l += [KconfigCheck('self_protection', 'clipos', 'DEBUG_VIRTUAL', 'y')]
479 l += [KconfigCheck('self_protection', 'clipos', 'STATIC_USERMODEHELPER', 'y')] # needs userspace support
480 l += [OR(KconfigCheck('self_protection', 'clipos', 'EFI_DISABLE_PCI_DMA', 'y'),
482 l += [KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set')]
483 l += [KconfigCheck('self_protection', 'clipos', 'RANDOM_TRUST_BOOTLOADER', 'is not set')]
484 l += [KconfigCheck('self_protection', 'clipos', 'RANDOM_TRUST_CPU', 'is not set')]
485 l += [AND(KconfigCheck('self_protection', 'clipos', 'RANDSTRUCT_PERFORMANCE', 'is not set'),
486 KconfigCheck('self_protection', 'clipos', 'GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set'),
488 if arch in ('X86_64', 'ARM64', 'X86_32'):
489 l += [AND(KconfigCheck('self_protection', 'clipos', 'STACKLEAK_METRICS', 'is not set'),
491 gcc_plugins_support_is_set)]
492 l += [AND(KconfigCheck('self_protection', 'clipos', 'STACKLEAK_RUNTIME_DISABLE', 'is not set'),
494 gcc_plugins_support_is_set)]
495 if arch in ('X86_64', 'X86_32'):
496 l += [AND(KconfigCheck('self_protection', 'clipos', 'INTEL_IOMMU_DEFAULT_ON', 'y'),
497 iommu_support_is_set)]
499 l += [AND(KconfigCheck('self_protection', 'clipos', 'INTEL_IOMMU_SVM', 'y'),
500 iommu_support_is_set)]
502 l += [AND(KconfigCheck('self_protection', 'clipos', 'INTEL_IOMMU', 'y'),
503 iommu_support_is_set)]
505 # 'self_protection', 'my'
506 l += [OR(KconfigCheck('self_protection', 'my', 'RESET_ATTACK_MITIGATION', 'y'),
507 efi_not_set)] # needs userspace support (systemd)
508 l += [OR(KconfigCheck('self_protection', 'my', 'UBSAN_LOCAL_BOUNDS', 'y'),
509 AND(ubsan_bounds_is_set,
512 l += [KconfigCheck('self_protection', 'my', 'SLS', 'y')] # vs CVE-2021-26341 in Straight-Line-Speculation
513 l += [AND(KconfigCheck('self_protection', 'my', 'AMD_IOMMU_V2', 'y'),
514 iommu_support_is_set)]
516 l += [KconfigCheck('self_protection', 'my', 'SHADOW_CALL_STACK', 'y')] # maybe it's alternative to STACKPROTECTOR_STRONG
517 l += [KconfigCheck('self_protection', 'my', 'KASAN_HW_TAGS', 'y')]
518 cfi_clang_is_set = KconfigCheck('self_protection', 'my', 'CFI_CLANG', 'y')
519 l += [cfi_clang_is_set]
520 l += [AND(KconfigCheck('self_protection', 'my', 'CFI_PERMISSIVE', 'is not set'),
524 if arch in ('X86_64', 'ARM64', 'X86_32'):
525 l += [KconfigCheck('security_policy', 'defconfig', 'SECURITY', 'y')] # and choose your favourite LSM
527 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY', 'y')] # and choose your favourite LSM
528 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_YAMA', 'y')]
529 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LANDLOCK', 'y')]
530 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DISABLE', 'is not set')]
531 l += [KconfigCheck('security_policy', 'clipos', 'SECURITY_LOCKDOWN_LSM', 'y')]
532 l += [KconfigCheck('security_policy', 'clipos', 'SECURITY_LOCKDOWN_LSM_EARLY', 'y')]
533 l += [KconfigCheck('security_policy', 'clipos', 'LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y')]
534 l += [KconfigCheck('security_policy', 'my', 'SECURITY_WRITABLE_HOOKS', 'is not set')] # refers to SECURITY_SELINUX_DISABLE
535 l += [KconfigCheck('security_policy', 'my', 'SECURITY_SAFESETID', 'y')]
536 loadpin_is_set = KconfigCheck('security_policy', 'my', 'SECURITY_LOADPIN', 'y')
537 l += [loadpin_is_set] # needs userspace support
538 l += [AND(KconfigCheck('security_policy', 'my', 'SECURITY_LOADPIN_ENFORCE', 'y'),
541 # 'cut_attack_surface', 'defconfig'
542 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'BPF_UNPRIV_DEFAULT_OFF', 'y'),
543 bpf_syscall_not_set)] # see unprivileged_bpf_disabled
544 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP', 'y')]
545 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP_FILTER', 'y')]
546 if arch in ('X86_64', 'ARM64', 'X86_32'):
547 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'STRICT_DEVMEM', 'y'),
548 devmem_not_set)] # refers to LOCKDOWN
550 # 'cut_attack_surface', 'kspp'
551 l += [KconfigCheck('cut_attack_surface', 'kspp', 'SECURITY_DMESG_RESTRICT', 'y')]
552 l += [KconfigCheck('cut_attack_surface', 'kspp', 'ACPI_CUSTOM_METHOD', 'is not set')] # refers to LOCKDOWN
553 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_BRK', 'is not set')]
554 l += [KconfigCheck('cut_attack_surface', 'kspp', 'DEVKMEM', 'is not set')] # refers to LOCKDOWN
555 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_VDSO', 'is not set')]
556 l += [KconfigCheck('cut_attack_surface', 'kspp', 'BINFMT_MISC', 'is not set')]
557 l += [KconfigCheck('cut_attack_surface', 'kspp', 'INET_DIAG', 'is not set')]
558 l += [KconfigCheck('cut_attack_surface', 'kspp', 'KEXEC', 'is not set')] # refers to LOCKDOWN
559 l += [KconfigCheck('cut_attack_surface', 'kspp', 'PROC_KCORE', 'is not set')] # refers to LOCKDOWN
560 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_PTYS', 'is not set')]
561 l += [KconfigCheck('cut_attack_surface', 'kspp', 'HIBERNATION', 'is not set')] # refers to LOCKDOWN
562 l += [KconfigCheck('cut_attack_surface', 'kspp', 'IA32_EMULATION', 'is not set')]
563 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_X32', 'is not set')]
564 l += [KconfigCheck('cut_attack_surface', 'kspp', 'MODIFY_LDT_SYSCALL', 'is not set')]
565 l += [KconfigCheck('cut_attack_surface', 'kspp', 'OABI_COMPAT', 'is not set')]
566 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_MSR', 'is not set')] # refers to LOCKDOWN
567 l += [modules_not_set]
568 l += [devmem_not_set]
569 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'IO_STRICT_DEVMEM', 'y'),
570 devmem_not_set)] # refers to LOCKDOWN
572 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'STRICT_DEVMEM', 'y'),
573 devmem_not_set)] # refers to LOCKDOWN
575 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y')] # 'vsyscall=none'
577 # 'cut_attack_surface', 'grsec'
578 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ZSMALLOC_STAT', 'is not set')]
579 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PAGE_OWNER', 'is not set')]
580 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_KMEMLEAK', 'is not set')]
581 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BINFMT_AOUT', 'is not set')]
582 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KPROBE_EVENTS', 'is not set')]
583 l += [KconfigCheck('cut_attack_surface', 'grsec', 'UPROBE_EVENTS', 'is not set')]
584 l += [KconfigCheck('cut_attack_surface', 'grsec', 'GENERIC_TRACER', 'is not set')] # refers to LOCKDOWN
585 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FUNCTION_TRACER', 'is not set')]
586 l += [KconfigCheck('cut_attack_surface', 'grsec', 'STACK_TRACER', 'is not set')]
587 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HIST_TRIGGERS', 'is not set')]
588 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BLK_DEV_IO_TRACE', 'is not set')]
589 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_VMCORE', 'is not set')]
590 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_PAGE_MONITOR', 'is not set')]
591 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USELIB', 'is not set')]
592 l += [KconfigCheck('cut_attack_surface', 'grsec', 'CHECKPOINT_RESTORE', 'is not set')]
593 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USERFAULTFD', 'is not set')]
594 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HWPOISON_INJECT', 'is not set')]
595 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MEM_SOFT_DIRTY', 'is not set')]
596 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEVPORT', 'is not set')] # refers to LOCKDOWN
597 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set')] # refers to LOCKDOWN
598 l += [KconfigCheck('cut_attack_surface', 'grsec', 'NOTIFIER_ERROR_INJECTION', 'is not set')]
599 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FAIL_FUTEX', 'is not set')]
600 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PUNIT_ATOM_DEBUG', 'is not set')]
601 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ACPI_CONFIGFS', 'is not set')]
602 l += [KconfigCheck('cut_attack_surface', 'grsec', 'EDAC_DEBUG', 'is not set')]
603 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DRM_I915_DEBUG', 'is not set')]
604 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BCACHE_CLOSURES_DEBUG', 'is not set')]
605 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DVB_C8SECTPFE', 'is not set')]
606 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_SLRAM', 'is not set')]
607 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_PHRAM', 'is not set')]
608 l += [KconfigCheck('cut_attack_surface', 'grsec', 'IO_URING', 'is not set')]
609 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCMP', 'is not set')]
610 l += [KconfigCheck('cut_attack_surface', 'grsec', 'RSEQ', 'is not set')]
611 l += [KconfigCheck('cut_attack_surface', 'grsec', 'LATENCYTOP', 'is not set')]
612 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCOV', 'is not set')]
613 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROVIDE_OHCI1394_DMA_INIT', 'is not set')]
614 l += [KconfigCheck('cut_attack_surface', 'grsec', 'SUNRPC_DEBUG', 'is not set')]
615 l += [AND(KconfigCheck('cut_attack_surface', 'grsec', 'PTDUMP_DEBUGFS', 'is not set'),
616 KconfigCheck('cut_attack_surface', 'grsec', 'X86_PTDUMP', 'is not set'))]
618 # 'cut_attack_surface', 'maintainer'
619 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'DRM_LEGACY', 'is not set')] # recommended by Daniel Vetter in /issues/38
620 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'FB', 'is not set')] # recommended by Daniel Vetter in /issues/38
621 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'VT', 'is not set')] # recommended by Daniel Vetter in /issues/38
622 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD', 'is not set')] # recommended by Denis Efremov in /pull/54
623 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD_RAWCMD', 'is not set')] # recommended by Denis Efremov in /pull/62
625 # 'cut_attack_surface', 'grapheneos'
626 l += [KconfigCheck('cut_attack_surface', 'grapheneos', 'AIO', 'is not set')]
628 # 'cut_attack_surface', 'clipos'
629 l += [KconfigCheck('cut_attack_surface', 'clipos', 'STAGING', 'is not set')]
630 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KSM', 'is not set')] # to prevent FLUSH+RELOAD attack
631 # l += [KconfigCheck('cut_attack_surface', 'clipos', 'IKCONFIG', 'is not set')] # no, IKCONFIG is needed for this check :)
632 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KALLSYMS', 'is not set')]
633 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_VSYSCALL_EMULATION', 'is not set')]
634 l += [KconfigCheck('cut_attack_surface', 'clipos', 'MAGIC_SYSRQ', 'is not set')]
635 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KEXEC_FILE', 'is not set')] # refers to LOCKDOWN (permissive)
636 l += [KconfigCheck('cut_attack_surface', 'clipos', 'USER_NS', 'is not set')] # user.max_user_namespaces=0
637 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_CPUID', 'is not set')]
638 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_IOPL_IOPERM', 'is not set')] # refers to LOCKDOWN
639 l += [KconfigCheck('cut_attack_surface', 'clipos', 'ACPI_TABLE_UPGRADE', 'is not set')] # refers to LOCKDOWN
640 l += [KconfigCheck('cut_attack_surface', 'clipos', 'EFI_CUSTOM_SSDT_OVERLAYS', 'is not set')]
641 l += [AND(KconfigCheck('cut_attack_surface', 'clipos', 'LDISC_AUTOLOAD', 'is not set'),
642 KconfigCheck('cut_attack_surface', 'clipos', 'LDISC_AUTOLOAD'))] # option presence check
643 if arch in ('X86_64', 'X86_32'):
644 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_INTEL_TSX_MODE_OFF', 'y')] # tsx=off
646 # 'cut_attack_surface', 'lockdown'
647 l += [bpf_syscall_not_set] # refers to LOCKDOWN
648 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'EFI_TEST', 'is not set')] # refers to LOCKDOWN
649 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'MMIOTRACE_TEST', 'is not set')] # refers to LOCKDOWN
650 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'KPROBES', 'is not set')] # refers to LOCKDOWN
652 # 'cut_attack_surface', 'my'
653 l += [OR(KconfigCheck('cut_attack_surface', 'my', 'TRIM_UNUSED_KSYMS', 'y'),
655 l += [KconfigCheck('cut_attack_surface', 'my', 'MMIOTRACE', 'is not set')] # refers to LOCKDOWN (permissive)
656 l += [KconfigCheck('cut_attack_surface', 'my', 'LIVEPATCH', 'is not set')]
657 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_DCCP', 'is not set')]
658 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_SCTP', 'is not set')]
659 l += [KconfigCheck('cut_attack_surface', 'my', 'FTRACE', 'is not set')] # refers to LOCKDOWN
660 l += [KconfigCheck('cut_attack_surface', 'my', 'VIDEO_VIVID', 'is not set')]
661 l += [KconfigCheck('cut_attack_surface', 'my', 'INPUT_EVBUG', 'is not set')] # Can be used as a keylogger
662 l += [KconfigCheck('cut_attack_surface', 'my', 'KGDB', 'is not set')]
665 if arch in ('X86_64', 'ARM64', 'X86_32'):
666 l += [KconfigCheck('harden_userspace', 'defconfig', 'INTEGRITY', 'y')]
668 l += [KconfigCheck('harden_userspace', 'my', 'INTEGRITY', 'y')]
670 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_PTR_AUTH', 'y')]
671 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_BTI', 'y')]
672 if arch in ('ARM', 'X86_32'):
673 l += [KconfigCheck('harden_userspace', 'defconfig', 'VMSPLIT_3G', 'y')]
674 if arch in ('X86_64', 'ARM64'):
675 l += [KconfigCheck('harden_userspace', 'clipos', 'ARCH_MMAP_RND_BITS', '32')]
676 if arch in ('X86_32', 'ARM'):
677 l += [KconfigCheck('harden_userspace', 'my', 'ARCH_MMAP_RND_BITS', '16')]
680 def add_cmdline_checks(l, arch):
681 # Calling the CmdlineCheck class constructor:
682 # CmdlineCheck(reason, decision, name, expected)
684 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
685 # when the tool doesn't check the cmdline.
687 # [!] Make sure that values of the options in CmdlineChecks need normalization.
688 # For more info see normalize_cmdline_options().
690 # A common pattern for checking the 'param_x' cmdline parameter
691 # that __overrides__ the 'PARAM_X_DEFAULT' kconfig option:
692 # l += [OR(CmdlineCheck(reason, decision, 'param_x', '1'),
693 # AND(KconfigCheck(reason, decision, 'PARAM_X_DEFAULT_ON', 'y'),
694 # CmdlineCheck(reason, decision, 'param_x, 'is not set')))]
696 # Here we don't check the kconfig options or minimal kernel version
697 # required for the cmdline parameters. That would make the checks
698 # very complex and not give a 100% guarantee anyway.
700 # 'self_protection', 'defconfig'
702 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', 'full'),
703 AND(KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y'),
704 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set')))]
706 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', '1'),
707 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set'))]
709 # 'self_protection', 'kspp'
710 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', '1'),
711 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y'),
712 CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', 'is not set')))]
713 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_free', '1'),
714 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
715 CmdlineCheck('self_protection', 'kspp', 'init_on_free', 'is not set')),
716 AND(CmdlineCheck('self_protection', 'kspp', 'page_poison', '1'),
717 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'),
718 CmdlineCheck('self_protection', 'kspp', 'slub_debug', 'P')))]
719 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_nomerge'),
720 AND(KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set'),
721 CmdlineCheck('self_protection', 'kspp', 'slab_merge', 'is not set')))] # option presence check
722 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.strict', '1'),
723 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y'),
724 CmdlineCheck('self_protection', 'kspp', 'iommu.strict', 'is not set')))]
725 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', '0'),
726 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set'),
727 CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', 'is not set')))]
728 # The cmdline checks compatible with the kconfig recommendations of the KSPP project...
729 l += [CmdlineCheck('self_protection', 'kspp', 'nokaslr', 'is not set')]
730 l += [OR(CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', '1'),
731 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y'),
732 CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', 'is not set')))]
733 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', '0'),
734 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
735 CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', 'is not set')))] # ... the end
736 if arch in ('X86_64', 'ARM64', 'X86_32'):
737 l += [OR(CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', '1'),
738 AND(KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y'),
739 CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', 'is not set')))]
740 if arch in ('X86_64', 'X86_32'):
741 l += [CmdlineCheck('self_protection', 'kspp', 'pti', 'on')]
743 # 'self_protection', 'clipos'
744 l += [CmdlineCheck('self_protection', 'clipos', 'page_alloc.shuffle', '1')]
746 # 'self_protection', 'my'
747 l += [CmdlineCheck('self_protection', 'my', 'nosmep', 'is not set')]
748 l += [CmdlineCheck('self_protection', 'my', 'nosmap', 'is not set')]
750 # 'cut_attack_surface', 'kspp'
752 l += [OR(CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'none'),
753 AND(KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y'),
754 CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'is not set')))]
756 # 'cut_attack_surface', 'grsec'
757 # The cmdline checks compatible with the kconfig options disabled by grsecurity...
758 l += [OR(CmdlineCheck('cut_attack_surface', 'grsec', 'debugfs', 'off'),
759 KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set'))] # ... the end
762 def print_unknown_options(checklist, parsed_options):
766 if o1.type != 'complex':
767 known_options.append(o1.name)
770 if o2.type != 'complex':
771 if hasattr(o2, 'name'):
772 known_options.append(o2.name)
775 assert(o3.type != 'complex'), \
776 'unexpected ComplexOptCheck inside {}'.format(o2.name)
777 if hasattr(o3, 'name'):
778 known_options.append(o3.name)
780 for option, value in parsed_options.items():
781 if option not in known_options:
782 print('[?] No check for option {} ({})'.format(option, value))
785 def print_checklist(mode, checklist, with_results):
789 output.append(o.json_dump(with_results))
790 print(json.dumps(output))
797 print('=' * sep_line_len)
798 print('{:^40}|{:^7}|{:^12}|{:^10}|{:^18}'.format('option name', 'type', 'desired val', 'decision', 'reason'), end='')
800 print('| {}'.format('check result'), end='')
802 print('=' * sep_line_len)
805 for opt in checklist:
807 if mode == 'show_ok':
808 if not opt.result.startswith('OK'):
810 if mode == 'show_fail':
811 if not opt.result.startswith('FAIL'):
813 opt.table_print(mode, with_results)
815 if mode == 'verbose':
816 print('-' * sep_line_len)
821 fail_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), checklist)))
823 ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), checklist)))
825 if mode == 'show_ok':
826 fail_suppressed = ' (suppressed in output)'
827 if mode == 'show_fail':
828 ok_suppressed = ' (suppressed in output)'
830 print('[+] Config check is finished: \'OK\' - {}{} / \'FAIL\' - {}{}'.format(ok_count, ok_suppressed, fail_count, fail_suppressed))
833 def populate_simple_opt_with_data(opt, data, data_type):
834 assert(opt.type != 'complex'), \
835 'unexpected ComplexOptCheck "{}"'.format(opt.name)
836 assert(opt.type in SIMPLE_OPTION_TYPES), \
837 'invalid opt type "{}"'.format(opt.type)
838 assert(data_type in SIMPLE_OPTION_TYPES), \
839 'invalid data type "{}"'.format(data_type)
841 if data_type != opt.type:
844 if data_type in ('kconfig', 'cmdline'):
845 opt.state = data.get(opt.name, None)
847 assert(data_type == 'version'), \
848 'unexpected data type "{}"'.format(data_type)
852 def populate_opt_with_data(opt, data, data_type):
853 if opt.type == 'complex':
855 if o.type == 'complex':
856 # Recursion for nested ComplexOptCheck objects
857 populate_opt_with_data(o, data, data_type)
859 populate_simple_opt_with_data(o, data, data_type)
861 assert(opt.type in ('kconfig', 'cmdline')), \
862 'bad type "{}" for a simple check'.format(opt.type)
863 populate_simple_opt_with_data(opt, data, data_type)
866 def populate_with_data(checklist, data, data_type):
867 for opt in checklist:
868 populate_opt_with_data(opt, data, data_type)
871 def perform_checks(checklist):
872 for opt in checklist:
876 def parse_kconfig_file(parsed_options, fname):
877 with open(fname, 'r') as f:
878 opt_is_on = re.compile("CONFIG_[a-zA-Z0-9_]*=[a-zA-Z0-9_\"]*")
879 opt_is_off = re.compile("# CONFIG_[a-zA-Z0-9_]* is not set")
881 for line in f.readlines():
886 if opt_is_on.match(line):
887 option, value = line.split('=', 1)
888 if value == 'is not set':
889 sys.exit('[!] ERROR: bad enabled kconfig option "{}"'.format(line))
890 elif opt_is_off.match(line):
891 option, value = line[2:].split(' ', 1)
892 if value != 'is not set':
893 sys.exit('[!] ERROR: bad disabled kconfig option "{}"'.format(line))
895 if option in parsed_options:
896 sys.exit('[!] ERROR: kconfig option "{}" exists multiple times'.format(line))
899 parsed_options[option] = value
902 def normalize_cmdline_options(option, value):
903 # Don't normalize the cmdline option values if
904 # the Linux kernel doesn't use kstrtobool() for them
906 # See pti_check_boottime_disable() in linux/arch/x86/mm/pti.c
908 if option == 'debugfs':
909 # See debugfs_kernel() in fs/debugfs/inode.c
912 # Implement a limited part of the kstrtobool() logic
913 if value in ('1', 'on', 'On', 'ON', 'y', 'Y', 'yes', 'Yes', 'YES'):
915 if value in ('0', 'off', 'Off', 'OFF', 'n', 'N', 'no', 'No', 'NO'):
918 # Preserve unique values
922 def parse_cmdline_file(parsed_options, fname):
923 with open(fname, 'r') as f:
929 sys.exit('[!] ERROR: more than one line in "{}"'.format(fname))
933 name, value = opt.split('=', 1)
936 value = '' # '' is not None
937 value = normalize_cmdline_options(name, value)
938 parsed_options[name] = value
944 # - reporting about unknown kernel options in the kconfig
945 # - verbose printing of ComplexOptCheck items
946 # * json mode for printing the results in JSON format
947 report_modes = ['verbose', 'json', 'show_ok', 'show_fail']
948 supported_archs = ['X86_64', 'X86_32', 'ARM64', 'ARM']
949 parser = ArgumentParser(prog='kconfig-hardened-check',
950 description='A tool for checking the security hardening options of the Linux kernel')
951 parser.add_argument('--version', action='version', version='%(prog)s ' + __version__)
952 parser.add_argument('-p', '--print', choices=supported_archs,
953 help='print security hardening preferences for the selected architecture')
954 parser.add_argument('-c', '--config',
955 help='check the kernel kconfig file against these preferences')
956 parser.add_argument('-l', '--cmdline',
957 help='check the kernel cmdline file against these preferences')
958 parser.add_argument('-m', '--mode', choices=report_modes,
959 help='choose the report mode')
960 args = parser.parse_args()
966 print('[+] Special report mode: {}'.format(mode))
968 config_checklist = []
972 sys.exit('[!] ERROR: --config and --print can\'t be used together')
975 print('[+] Kconfig file to check: {}'.format(args.config))
977 print('[+] Kernel cmdline file to check: {}'.format(args.cmdline))
979 arch, msg = detect_arch(args.config, supported_archs)
981 sys.exit('[!] ERROR: {}'.format(msg))
983 print('[+] Detected architecture: {}'.format(arch))
985 kernel_version, msg = detect_kernel_version(args.config)
986 if not kernel_version:
987 sys.exit('[!] ERROR: {}'.format(msg))
989 print('[+] Detected kernel version: {}.{}'.format(kernel_version[0], kernel_version[1]))
991 compiler, msg = detect_compiler(args.config)
994 print('[+] Detected compiler: {}'.format(compiler))
996 print('[-] Can\'t detect the compiler: {}'.format(msg))
998 # add relevant kconfig checks to the checklist
999 add_kconfig_checks(config_checklist, arch)
1002 # add relevant cmdline checks to the checklist
1003 add_cmdline_checks(config_checklist, arch)
1005 # populate the checklist with the parsed kconfig data
1006 parsed_kconfig_options = OrderedDict()
1007 parse_kconfig_file(parsed_kconfig_options, args.config)
1008 populate_with_data(config_checklist, parsed_kconfig_options, 'kconfig')
1009 populate_with_data(config_checklist, kernel_version, 'version')
1012 # populate the checklist with the parsed kconfig data
1013 parsed_cmdline_options = OrderedDict()
1014 parse_cmdline_file(parsed_cmdline_options, args.cmdline)
1015 populate_with_data(config_checklist, parsed_cmdline_options, 'cmdline')
1017 # now everything is ready for performing the checks
1018 perform_checks(config_checklist)
1020 # finally print the results
1021 if mode == 'verbose':
1022 print_unknown_options(config_checklist, parsed_kconfig_options)
1023 print_checklist(mode, config_checklist, True)
1027 sys.exit('[!] ERROR: checking cmdline doesn\'t work without checking kconfig')
1030 if mode in ('show_ok', 'show_fail'):
1031 sys.exit('[!] ERROR: wrong mode "{}" for --print'.format(mode))
1033 add_kconfig_checks(config_checklist, arch)
1034 add_cmdline_checks(config_checklist, arch)
1036 print('[+] Printing kernel security hardening preferences for {}...'.format(arch))
1037 print_checklist(mode, config_checklist, False)