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?)
16 # Mitigations of CPU vulnerabilities:
19 # spec_store_bypass_disable=on
21 # l1d_flush=on (a part of the l1tf option)
29 # sysrq_always_enabled
34 # Hardware tag-based KASAN with arm64 Memory Tagging Extension (MTE):
36 # kasan.stacktrace=off
39 # N.B. Hardening sysctls:
40 # kernel.kptr_restrict=2 (or 1?)
41 # kernel.dmesg_restrict=1 (also see the kconfig option)
42 # kernel.perf_event_paranoid=3
43 # kernel.kexec_load_disabled=1
44 # kernel.yama.ptrace_scope=3
45 # user.max_user_namespaces=0
46 # what about bpf_jit_enable?
47 # kernel.unprivileged_bpf_disabled=1
48 # net.core.bpf_jit_harden=2
49 # vm.unprivileged_userfaultfd=0
50 # (at first, it disabled unprivileged userfaultfd,
51 # and since v5.11 it enables unprivileged userfaultfd for user-mode only)
52 # vm.mmap_min_addr has a good value
53 # dev.tty.ldisc_autoload=0
54 # fs.protected_symlinks=1
55 # fs.protected_hardlinks=1
56 # fs.protected_fifos=2
57 # fs.protected_regular=2
59 # kernel.modules_disabled=1
60 # kernel.randomize_va_space = 2
63 # pylint: disable=missing-module-docstring,missing-class-docstring,missing-function-docstring
64 # pylint: disable=line-too-long,invalid-name,too-many-branches,too-many-statements
68 from argparse import ArgumentParser
69 from collections import OrderedDict
72 from .__about__ import __version__
74 SIMPLE_OPTION_TYPES = ('kconfig', 'version', 'cmdline')
77 def __init__(self, reason, decision, name, expected):
78 assert(name and name == name.strip() and len(name.split()) == 1), \
79 'invalid name "{}" for {}'.format(name, self.__class__.__name__)
82 assert(decision and decision == decision.strip() and len(decision.split()) == 1), \
83 'invalid decision "{}" for "{}" check'.format(decision, name)
84 self.decision = decision
86 assert(reason and reason == reason.strip() and len(reason.split()) == 1), \
87 'invalid reason "{}" for "{}" check'.format(reason, name)
90 assert(expected and expected == expected.strip()), \
91 'invalid expected value "{}" for "{}" check (1)'.format(expected, name)
92 val_len = len(expected.split())
94 assert(expected == 'is not set' or expected == 'is not off'), \
95 'invalid expected value "{}" for "{}" check (2)'.format(expected, name)
97 assert(expected == 'is present'), \
98 'invalid expected value "{}" for "{}" check (3)'.format(expected, name)
100 assert(val_len == 1), \
101 'invalid expected value "{}" for "{}" check (4)'.format(expected, name)
102 self.expected = expected
112 # handle the 'is present' check
113 if self.expected == 'is present':
114 if self.state is None:
115 self.result = 'FAIL: is not present'
117 self.result = 'OK: is present'
120 # handle the 'is not off' option check
121 if self.expected == 'is not off':
122 if self.state == 'off':
123 self.result = 'FAIL: is off'
124 elif self.state is None:
125 self.result = 'FAIL: is off, not found'
127 self.result = 'OK: is not off, "' + self.state + '"'
130 # handle the option value check
131 if self.expected == self.state:
133 elif self.state is None:
134 if self.expected == 'is not set':
135 self.result = 'OK: is not found'
137 self.result = 'FAIL: is not found'
139 self.result = 'FAIL: "' + self.state + '"'
141 def table_print(self, _mode, with_results):
142 print('{:<40}|{:^7}|{:^12}|{:^10}|{:^18}'.format(self.name, self.type, self.expected, self.decision, self.reason), end='')
144 print('| {}'.format(self.result), end='')
146 def json_dump(self, with_results):
147 dump = [self.name, self.type, self.expected, self.decision, self.reason]
149 dump.append(self.result)
153 class KconfigCheck(OptCheck):
154 def __init__(self, *args, **kwargs):
155 super().__init__(*args, **kwargs)
156 self.name = 'CONFIG_' + self.name
163 class CmdlineCheck(OptCheck):
170 def __init__(self, ver_expected):
171 assert(ver_expected and isinstance(ver_expected, tuple) and len(ver_expected) == 2), \
172 'invalid version "{}" for VersionCheck'.format(ver_expected)
173 self.ver_expected = ver_expected
182 if self.ver[0] > self.ver_expected[0]:
183 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
185 if self.ver[0] < self.ver_expected[0]:
186 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
188 if self.ver[1] >= self.ver_expected[1]:
189 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
191 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
193 def table_print(self, _mode, with_results):
194 ver_req = 'kernel version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
195 print('{:<91}'.format(ver_req), end='')
197 print('| {}'.format(self.result), end='')
200 class ComplexOptCheck:
201 def __init__(self, *opts):
204 'empty {} check'.format(self.__class__.__name__)
205 assert(len(self.opts) != 1), \
206 'useless {} check: {}'.format(self.__class__.__name__, opts)
207 assert(isinstance(opts[0], (KconfigCheck, CmdlineCheck))), \
208 'invalid {} check: {}'.format(self.__class__.__name__, opts)
217 return self.opts[0].name
221 return self.opts[0].expected
223 def table_print(self, mode, with_results):
224 if mode == 'verbose':
225 print(' {:87}'.format('<<< ' + self.__class__.__name__ + ' >>>'), end='')
227 print('| {}'.format(self.result), end='')
230 o.table_print(mode, with_results)
233 o.table_print(mode, False)
235 print('| {}'.format(self.result), end='')
237 def json_dump(self, with_results):
238 dump = self.opts[0].json_dump(False)
240 dump.append(self.result)
244 class OR(ComplexOptCheck):
245 # self.opts[0] is the option that this OR-check is about.
247 # OR(<X_is_hardened>, <X_is_disabled>)
248 # OR(<X_is_hardened>, <old_X_is_hardened>)
250 for i, opt in enumerate(self.opts):
252 if opt.result.startswith('OK'):
253 self.result = opt.result
254 # Add more info for additional checks:
256 if opt.result == 'OK':
257 self.result = 'OK: {} is "{}"'.format(opt.name, opt.expected)
258 elif opt.result == 'OK: is not found':
259 self.result = 'OK: {} is not found'.format(opt.name)
260 elif opt.result == 'OK: is present':
261 self.result = 'OK: {} is present'.format(opt.name)
262 elif opt.result.startswith('OK: is not off'):
263 self.result = 'OK: {} is not off'.format(opt.name)
265 # VersionCheck provides enough info
266 assert(opt.result.startswith('OK: version')), \
267 'unexpected OK description "{}"'.format(opt.result)
269 self.result = self.opts[0].result
272 class AND(ComplexOptCheck):
273 # self.opts[0] is the option that this AND-check is about.
275 # AND(<suboption>, <main_option>)
276 # Suboption is not checked if checking of the main_option is failed.
277 # AND(<X_is_disabled>, <old_X_is_disabled>)
279 for i, opt in reversed(list(enumerate(self.opts))):
282 self.result = opt.result
284 if not opt.result.startswith('OK'):
285 # This FAIL is caused by additional checks,
286 # and not by the main option that this AND-check is about.
287 # Describe the reason of the FAIL.
288 if opt.result.startswith('FAIL: \"') or opt.result == 'FAIL: is not found':
289 self.result = 'FAIL: {} is not "{}"'.format(opt.name, opt.expected)
290 elif opt.result == 'FAIL: is not present':
291 self.result = 'FAIL: {} is not present'.format(opt.name)
292 elif opt.result == 'FAIL: is off':
293 self.result = 'FAIL: {} is off'.format(opt.name)
294 elif opt.result == 'FAIL: is off, not found':
295 self.result = 'FAIL: {} is off, not found'.format(opt.name)
297 # VersionCheck provides enough info
298 self.result = opt.result
299 assert(opt.result.startswith('FAIL: version')), \
300 'unexpected FAIL description "{}"'.format(opt.result)
304 def detect_arch(fname, archs):
305 with open(fname, 'r') as f:
306 arch_pattern = re.compile("CONFIG_[a-zA-Z0-9_]*=y")
308 for line in f.readlines():
309 if arch_pattern.match(line):
310 option, _ = line[7:].split('=', 1)
315 return None, 'more than one supported architecture is detected'
317 return None, 'failed to detect architecture'
321 def detect_kernel_version(fname):
322 with open(fname, 'r') as f:
323 ver_pattern = re.compile("# Linux/.* Kernel Configuration")
324 for line in f.readlines():
325 if ver_pattern.match(line):
329 ver_numbers = ver_str.split('.')
330 if len(ver_numbers) < 3 or not ver_numbers[0].isdigit() or not ver_numbers[1].isdigit():
331 msg = 'failed to parse the version "' + ver_str + '"'
333 return (int(ver_numbers[0]), int(ver_numbers[1])), None
334 return None, 'no kernel version detected'
337 def detect_compiler(fname):
340 with open(fname, 'r') as f:
341 gcc_version_pattern = re.compile("CONFIG_GCC_VERSION=[0-9]*")
342 clang_version_pattern = re.compile("CONFIG_CLANG_VERSION=[0-9]*")
343 for line in f.readlines():
344 if gcc_version_pattern.match(line):
345 gcc_version = line[19:-1]
346 if clang_version_pattern.match(line):
347 clang_version = line[21:-1]
348 if not gcc_version or not clang_version:
349 return None, 'no CONFIG_GCC_VERSION or CONFIG_CLANG_VERSION'
350 if gcc_version == '0' and clang_version != '0':
351 return 'CLANG ' + clang_version, 'OK'
352 if gcc_version != '0' and clang_version == '0':
353 return 'GCC ' + gcc_version, 'OK'
354 sys.exit('[!] ERROR: invalid GCC_VERSION and CLANG_VERSION: {} {}'.format(gcc_version, clang_version))
357 def add_kconfig_checks(l, arch):
358 # Calling the KconfigCheck class constructor:
359 # KconfigCheck(reason, decision, name, expected)
361 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
362 # when the tool doesn't check the cmdline.
364 efi_not_set = KconfigCheck('-', '-', 'EFI', 'is not set')
365 cc_is_gcc = KconfigCheck('-', '-', 'CC_IS_GCC', 'y') # exists since v4.18
366 cc_is_clang = KconfigCheck('-', '-', 'CC_IS_CLANG', 'y') # exists since v4.18
368 modules_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'MODULES', 'is not set')
369 devmem_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'DEVMEM', 'is not set') # refers to LOCKDOWN
370 bpf_syscall_not_set = KconfigCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set') # refers to LOCKDOWN
372 # 'self_protection', 'defconfig'
373 l += [KconfigCheck('self_protection', 'defconfig', 'BUG', 'y')]
374 l += [KconfigCheck('self_protection', 'defconfig', 'SLUB_DEBUG', 'y')]
375 gcc_plugins_support_is_set = KconfigCheck('self_protection', 'defconfig', 'GCC_PLUGINS', 'y')
376 l += [gcc_plugins_support_is_set]
377 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR', 'y'),
378 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR', 'y'),
379 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_REGULAR', 'y'),
380 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_AUTO', 'y'),
381 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
382 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_STRONG', 'y'),
383 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
384 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_KERNEL_RWX', 'y'),
385 KconfigCheck('self_protection', 'defconfig', 'DEBUG_RODATA', 'y'))] # before v4.11
386 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_MODULE_RWX', 'y'),
387 KconfigCheck('self_protection', 'defconfig', 'DEBUG_SET_MODULE_RONX', 'y'),
388 modules_not_set)] # DEBUG_SET_MODULE_RONX was before v4.11
389 l += [OR(KconfigCheck('self_protection', 'defconfig', 'REFCOUNT_FULL', 'y'),
390 VersionCheck((5, 5)))] # REFCOUNT_FULL is enabled by default since v5.5
391 l += [KconfigCheck('self_protection', 'defconfig', 'THREAD_INFO_IN_TASK', 'y')]
392 iommu_support_is_set = KconfigCheck('self_protection', 'defconfig', 'IOMMU_SUPPORT', 'y')
393 l += [iommu_support_is_set] # is needed for mitigating DMA attacks
394 if arch in ('X86_64', 'ARM64', 'X86_32'):
395 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y')]
396 if arch in ('X86_64', 'ARM64'):
397 l += [KconfigCheck('self_protection', 'defconfig', 'VMAP_STACK', 'y')]
398 if arch in ('X86_64', 'X86_32'):
399 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE', 'y')]
400 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE_INTEL', 'y')]
401 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE_AMD', 'y')]
402 l += [KconfigCheck('self_protection', 'defconfig', 'MICROCODE', 'y')] # is needed for mitigating CPU bugs
403 l += [KconfigCheck('self_protection', 'defconfig', 'RETPOLINE', 'y')]
404 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_SMAP', 'y'),
405 VersionCheck((5, 19)))] # X86_SMAP is enabled by default since v5.19
406 l += [KconfigCheck('self_protection', 'defconfig', 'SYN_COOKIES', 'y')] # another reason?
407 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_UMIP', 'y'),
408 KconfigCheck('self_protection', 'defconfig', 'X86_INTEL_UMIP', 'y'))]
409 if arch in ('ARM64', 'ARM'):
410 l += [KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_PER_TASK', 'y')]
412 l += [KconfigCheck('self_protection', 'defconfig', 'PAGE_TABLE_ISOLATION', 'y')]
413 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MEMORY', 'y')]
414 l += [AND(KconfigCheck('self_protection', 'defconfig', 'INTEL_IOMMU', 'y'),
415 iommu_support_is_set)]
416 l += [AND(KconfigCheck('self_protection', 'defconfig', 'AMD_IOMMU', 'y'),
417 iommu_support_is_set)]
419 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PAN', 'y')]
420 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_EPAN', 'y')]
421 l += [KconfigCheck('self_protection', 'defconfig', 'UNMAP_KERNEL_AT_EL0', 'y')]
422 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_E0PD', 'y')]
423 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_EL2_VECTORS', 'y'),
424 AND(KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y'),
425 VersionCheck((5, 9))))] # HARDEN_EL2_VECTORS was included in RANDOMIZE_BASE in v5.9
426 l += [KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y')]
427 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PTR_AUTH_KERNEL', 'y')]
428 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_BTI_KERNEL', 'y')]
429 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y'),
430 VersionCheck((5, 10)))] # HARDEN_BRANCH_PREDICTOR is enabled by default since v5.10
431 l += [KconfigCheck('self_protection', 'defconfig', 'MITIGATE_SPECTRE_BRANCH_HISTORY', 'y')]
432 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_MTE', 'y')]
433 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MODULE_REGION_FULL', 'y')]
435 l += [KconfigCheck('self_protection', 'defconfig', 'CPU_SW_DOMAIN_PAN', 'y')]
436 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y')]
437 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_HISTORY', 'y')]
439 # 'self_protection', 'kspp'
440 l += [KconfigCheck('self_protection', 'kspp', 'BUG_ON_DATA_CORRUPTION', 'y')]
441 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_WX', 'y')]
442 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_STACK_END_CHECK', 'y')]
443 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_HARDENED', 'y')]
444 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_RANDOM', 'y')]
445 l += [KconfigCheck('self_protection', 'kspp', 'SHUFFLE_PAGE_ALLOCATOR', 'y')]
446 l += [KconfigCheck('self_protection', 'kspp', 'FORTIFY_SOURCE', 'y')]
447 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_LIST', 'y')]
448 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_VIRTUAL', 'y')]
449 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_SG', 'y')]
450 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_CREDENTIALS', 'y')]
451 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_NOTIFIERS', 'y')]
452 l += [KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y')]
453 l += [AND(KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_LATENT_ENTROPY', 'y'),
454 gcc_plugins_support_is_set)]
455 l += [KconfigCheck('self_protection', 'kspp', 'KFENCE', 'y')]
456 l += [KconfigCheck('self_protection', 'kspp', 'WERROR', 'y')]
457 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y')]
458 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set')] # true if IOMMU_DEFAULT_DMA_STRICT is set
459 l += [KconfigCheck('self_protection', 'kspp', 'ZERO_CALL_USED_REGS', 'y')]
460 l += [KconfigCheck('self_protection', 'kspp', 'HW_RANDOM_TPM', 'y')]
461 l += [KconfigCheck('self_protection', 'kspp', 'STATIC_USERMODEHELPER', 'y')] # needs userspace support
462 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_CORE', 'y')]
463 randstruct_is_set = OR(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_FULL', 'y'),
464 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT', 'y'))
465 l += [randstruct_is_set]
466 l += [AND(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_PERFORMANCE', 'is not set'),
467 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set'),
469 hardened_usercopy_is_set = KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y')
470 l += [hardened_usercopy_is_set]
471 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
472 hardened_usercopy_is_set)]
473 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_PAGESPAN', 'is not set'),
474 hardened_usercopy_is_set)]
475 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG', 'y'),
477 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_ALL', 'y'),
479 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_SHA512', 'y'),
481 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_FORCE', 'y'),
482 modules_not_set)] # refers to LOCKDOWN
483 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_STACK_ALL_ZERO', 'y'),
484 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y'))]
485 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
486 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'))]
487 # CONFIG_INIT_ON_FREE_DEFAULT_ON was added in v5.3.
488 # CONFIG_PAGE_POISONING_ZERO was removed in v5.11.
489 # Starting from v5.11 CONFIG_PAGE_POISONING unconditionally checks
490 # the 0xAA poison pattern on allocation.
491 # That brings higher performance penalty.
492 l += [OR(KconfigCheck('self_protection', 'kspp', 'EFI_DISABLE_PCI_DMA', 'y'),
494 l += [OR(KconfigCheck('self_protection', 'kspp', 'RESET_ATTACK_MITIGATION', 'y'),
495 efi_not_set)] # needs userspace support (systemd)
496 ubsan_bounds_is_set = KconfigCheck('self_protection', 'kspp', 'UBSAN_BOUNDS', 'y')
497 l += [ubsan_bounds_is_set]
498 l += [OR(KconfigCheck('self_protection', 'kspp', 'UBSAN_LOCAL_BOUNDS', 'y'),
499 AND(ubsan_bounds_is_set,
501 l += [AND(KconfigCheck('self_protection', 'kspp', 'UBSAN_TRAP', 'y'),
503 KconfigCheck('self_protection', 'kspp', 'UBSAN_SHIFT', 'is not set'),
504 KconfigCheck('self_protection', 'kspp', 'UBSAN_DIV_ZERO', 'is not set'),
505 KconfigCheck('self_protection', 'kspp', 'UBSAN_UNREACHABLE', 'is not set'),
506 KconfigCheck('self_protection', 'kspp', 'UBSAN_BOOL', 'is not set'),
507 KconfigCheck('self_protection', 'kspp', 'UBSAN_ENUM', 'is not set'),
508 KconfigCheck('self_protection', 'kspp', 'UBSAN_ALIGNMENT', 'is not set'))] # only array index bounds checking with traps
509 if arch in ('X86_64', 'ARM64', 'X86_32'):
510 l += [AND(KconfigCheck('self_protection', 'kspp', 'UBSAN_SANITIZE_ALL', 'y'),
511 ubsan_bounds_is_set)] # ARCH_HAS_UBSAN_SANITIZE_ALL is not enabled for ARM
512 stackleak_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STACKLEAK', 'y')
513 l += [AND(stackleak_is_set, gcc_plugins_support_is_set)]
514 l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_METRICS', 'is not set'),
516 gcc_plugins_support_is_set)]
517 l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_RUNTIME_DISABLE', 'is not set'),
519 gcc_plugins_support_is_set)]
520 l += [KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y')]
521 if arch in ('X86_64', 'ARM64'):
522 cfi_clang_is_set = KconfigCheck('self_protection', 'kspp', 'CFI_CLANG', 'y')
523 l += [cfi_clang_is_set]
524 l += [AND(KconfigCheck('self_protection', 'kspp', 'CFI_PERMISSIVE', 'is not set'),
526 if arch in ('X86_64', 'X86_32'):
527 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '65536')]
528 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU_DEFAULT_ON', 'y'),
529 iommu_support_is_set)]
530 if arch in ('ARM64', 'ARM'):
531 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '32768')]
532 l += [KconfigCheck('self_protection', 'kspp', 'SYN_COOKIES', 'y')] # another reason?
534 l += [KconfigCheck('self_protection', 'kspp', 'SLS', 'y')] # vs CVE-2021-26341 in Straight-Line-Speculation
535 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU_SVM', 'y'),
536 iommu_support_is_set)]
537 l += [AND(KconfigCheck('self_protection', 'kspp', 'AMD_IOMMU_V2', 'y'),
538 iommu_support_is_set)]
540 l += [KconfigCheck('self_protection', 'kspp', 'ARM64_SW_TTBR0_PAN', 'y')]
541 l += [KconfigCheck('self_protection', 'kspp', 'SHADOW_CALL_STACK', 'y')]
542 l += [KconfigCheck('self_protection', 'kspp', 'KASAN_HW_TAGS', 'y')]
544 l += [KconfigCheck('self_protection', 'kspp', 'PAGE_TABLE_ISOLATION', 'y')]
545 l += [KconfigCheck('self_protection', 'kspp', 'HIGHMEM64G', 'y')]
546 l += [KconfigCheck('self_protection', 'kspp', 'X86_PAE', 'y')]
547 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU', 'y'),
548 iommu_support_is_set)]
550 # 'self_protection', 'clipos'
551 l += [KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set')]
554 if arch in ('X86_64', 'ARM64', 'X86_32'):
555 l += [KconfigCheck('security_policy', 'defconfig', 'SECURITY', 'y')] # and choose your favourite LSM
557 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY', 'y')] # and choose your favourite LSM
558 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_YAMA', 'y')]
559 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LANDLOCK', 'y')]
560 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DISABLE', 'is not set')]
561 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_BOOTPARAM', 'is not set')]
562 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DEVELOP', 'is not set')]
563 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LOCKDOWN_LSM', 'y')]
564 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LOCKDOWN_LSM_EARLY', 'y')]
565 l += [KconfigCheck('security_policy', 'kspp', 'LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y')]
566 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_WRITABLE_HOOKS', 'is not set')] # refers to SECURITY_SELINUX_DISABLE
568 # 'cut_attack_surface', 'defconfig'
569 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'BPF_UNPRIV_DEFAULT_OFF', 'y'),
570 bpf_syscall_not_set)] # see unprivileged_bpf_disabled
571 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP', 'y')]
572 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP_FILTER', 'y')]
573 if arch in ('X86_64', 'ARM64', 'X86_32'):
574 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'STRICT_DEVMEM', 'y'),
575 devmem_not_set)] # refers to LOCKDOWN
577 # 'cut_attack_surface', 'kspp'
578 l += [KconfigCheck('cut_attack_surface', 'kspp', 'SECURITY_DMESG_RESTRICT', 'y')]
579 l += [KconfigCheck('cut_attack_surface', 'kspp', 'ACPI_CUSTOM_METHOD', 'is not set')] # refers to LOCKDOWN
580 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_BRK', 'is not set')]
581 l += [KconfigCheck('cut_attack_surface', 'kspp', 'DEVKMEM', 'is not set')] # refers to LOCKDOWN
582 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_VDSO', 'is not set')]
583 l += [KconfigCheck('cut_attack_surface', 'kspp', 'BINFMT_MISC', 'is not set')]
584 l += [KconfigCheck('cut_attack_surface', 'kspp', 'INET_DIAG', 'is not set')]
585 l += [KconfigCheck('cut_attack_surface', 'kspp', 'KEXEC', 'is not set')] # refers to LOCKDOWN
586 l += [KconfigCheck('cut_attack_surface', 'kspp', 'PROC_KCORE', 'is not set')] # refers to LOCKDOWN
587 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_PTYS', 'is not set')]
588 l += [KconfigCheck('cut_attack_surface', 'kspp', 'HIBERNATION', 'is not set')] # refers to LOCKDOWN
589 l += [KconfigCheck('cut_attack_surface', 'kspp', 'IA32_EMULATION', 'is not set')]
590 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_X32', 'is not set')]
591 l += [KconfigCheck('cut_attack_surface', 'kspp', 'MODIFY_LDT_SYSCALL', 'is not set')]
592 l += [KconfigCheck('cut_attack_surface', 'kspp', 'OABI_COMPAT', 'is not set')]
593 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_MSR', 'is not set')] # refers to LOCKDOWN
594 l += [modules_not_set]
595 l += [devmem_not_set]
596 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'IO_STRICT_DEVMEM', 'y'),
597 devmem_not_set)] # refers to LOCKDOWN
598 l += [AND(KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD', 'is not set'),
599 KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD', 'is present'))]
601 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'STRICT_DEVMEM', 'y'),
602 devmem_not_set)] # refers to LOCKDOWN
604 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y')] # 'vsyscall=none'
606 # 'cut_attack_surface', 'grsec'
607 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ZSMALLOC_STAT', 'is not set')]
608 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PAGE_OWNER', 'is not set')]
609 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_KMEMLEAK', 'is not set')]
610 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BINFMT_AOUT', 'is not set')]
611 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KPROBE_EVENTS', 'is not set')]
612 l += [KconfigCheck('cut_attack_surface', 'grsec', 'UPROBE_EVENTS', 'is not set')]
613 l += [KconfigCheck('cut_attack_surface', 'grsec', 'GENERIC_TRACER', 'is not set')] # refers to LOCKDOWN
614 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FUNCTION_TRACER', 'is not set')]
615 l += [KconfigCheck('cut_attack_surface', 'grsec', 'STACK_TRACER', 'is not set')]
616 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HIST_TRIGGERS', 'is not set')]
617 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BLK_DEV_IO_TRACE', 'is not set')]
618 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_VMCORE', 'is not set')]
619 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_PAGE_MONITOR', 'is not set')]
620 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USELIB', 'is not set')]
621 l += [KconfigCheck('cut_attack_surface', 'grsec', 'CHECKPOINT_RESTORE', 'is not set')]
622 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USERFAULTFD', 'is not set')]
623 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HWPOISON_INJECT', 'is not set')]
624 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MEM_SOFT_DIRTY', 'is not set')]
625 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEVPORT', 'is not set')] # refers to LOCKDOWN
626 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set')] # refers to LOCKDOWN
627 l += [KconfigCheck('cut_attack_surface', 'grsec', 'NOTIFIER_ERROR_INJECTION', 'is not set')]
628 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FAIL_FUTEX', 'is not set')]
629 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PUNIT_ATOM_DEBUG', 'is not set')]
630 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ACPI_CONFIGFS', 'is not set')]
631 l += [KconfigCheck('cut_attack_surface', 'grsec', 'EDAC_DEBUG', 'is not set')]
632 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DRM_I915_DEBUG', 'is not set')]
633 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BCACHE_CLOSURES_DEBUG', 'is not set')]
634 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DVB_C8SECTPFE', 'is not set')]
635 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_SLRAM', 'is not set')]
636 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_PHRAM', 'is not set')]
637 l += [KconfigCheck('cut_attack_surface', 'grsec', 'IO_URING', 'is not set')]
638 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCMP', 'is not set')]
639 l += [KconfigCheck('cut_attack_surface', 'grsec', 'RSEQ', 'is not set')]
640 l += [KconfigCheck('cut_attack_surface', 'grsec', 'LATENCYTOP', 'is not set')]
641 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCOV', 'is not set')]
642 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROVIDE_OHCI1394_DMA_INIT', 'is not set')]
643 l += [KconfigCheck('cut_attack_surface', 'grsec', 'SUNRPC_DEBUG', 'is not set')]
644 l += [AND(KconfigCheck('cut_attack_surface', 'grsec', 'PTDUMP_DEBUGFS', 'is not set'),
645 KconfigCheck('cut_attack_surface', 'grsec', 'X86_PTDUMP', 'is not set'))]
647 # 'cut_attack_surface', 'maintainer'
648 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'DRM_LEGACY', 'is not set')] # recommended by Daniel Vetter in /issues/38
649 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'FB', 'is not set')] # recommended by Daniel Vetter in /issues/38
650 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'VT', 'is not set')] # recommended by Daniel Vetter in /issues/38
651 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD', 'is not set')] # recommended by Denis Efremov in /pull/54
652 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD_RAWCMD', 'is not set')] # recommended by Denis Efremov in /pull/62
654 # 'cut_attack_surface', 'grapheneos'
655 l += [KconfigCheck('cut_attack_surface', 'grapheneos', 'AIO', 'is not set')]
657 # 'cut_attack_surface', 'clipos'
658 l += [KconfigCheck('cut_attack_surface', 'clipos', 'STAGING', 'is not set')]
659 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KSM', 'is not set')] # to prevent FLUSH+RELOAD attack
660 # l += [KconfigCheck('cut_attack_surface', 'clipos', 'IKCONFIG', 'is not set')] # no, IKCONFIG is needed for this check :)
661 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KALLSYMS', 'is not set')]
662 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_VSYSCALL_EMULATION', 'is not set')]
663 l += [KconfigCheck('cut_attack_surface', 'clipos', 'MAGIC_SYSRQ', 'is not set')]
664 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KEXEC_FILE', 'is not set')] # refers to LOCKDOWN (permissive)
665 l += [KconfigCheck('cut_attack_surface', 'clipos', 'USER_NS', 'is not set')] # user.max_user_namespaces=0
666 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_CPUID', 'is not set')]
667 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_IOPL_IOPERM', 'is not set')] # refers to LOCKDOWN
668 l += [KconfigCheck('cut_attack_surface', 'clipos', 'ACPI_TABLE_UPGRADE', 'is not set')] # refers to LOCKDOWN
669 l += [KconfigCheck('cut_attack_surface', 'clipos', 'EFI_CUSTOM_SSDT_OVERLAYS', 'is not set')]
670 l += [KconfigCheck('cut_attack_surface', 'clipos', 'COREDUMP', 'is not set')] # cut userspace attack surface
671 if arch in ('X86_64', 'X86_32'):
672 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_INTEL_TSX_MODE_OFF', 'y')] # tsx=off
674 # 'cut_attack_surface', 'lockdown'
675 l += [bpf_syscall_not_set] # refers to LOCKDOWN
676 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'EFI_TEST', 'is not set')] # refers to LOCKDOWN
677 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'MMIOTRACE_TEST', 'is not set')] # refers to LOCKDOWN
678 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'KPROBES', 'is not set')] # refers to LOCKDOWN
680 # 'cut_attack_surface', 'my'
681 l += [OR(KconfigCheck('cut_attack_surface', 'my', 'TRIM_UNUSED_KSYMS', 'y'),
683 l += [KconfigCheck('cut_attack_surface', 'my', 'MMIOTRACE', 'is not set')] # refers to LOCKDOWN (permissive)
684 l += [KconfigCheck('cut_attack_surface', 'my', 'LIVEPATCH', 'is not set')]
685 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_DCCP', 'is not set')]
686 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_SCTP', 'is not set')]
687 l += [KconfigCheck('cut_attack_surface', 'my', 'FTRACE', 'is not set')] # refers to LOCKDOWN
688 l += [KconfigCheck('cut_attack_surface', 'my', 'VIDEO_VIVID', 'is not set')]
689 l += [KconfigCheck('cut_attack_surface', 'my', 'INPUT_EVBUG', 'is not set')] # Can be used as a keylogger
690 l += [KconfigCheck('cut_attack_surface', 'my', 'KGDB', 'is not set')]
693 if arch in ('X86_64', 'ARM64', 'X86_32'):
694 l += [KconfigCheck('harden_userspace', 'defconfig', 'INTEGRITY', 'y')]
696 l += [KconfigCheck('harden_userspace', 'my', 'INTEGRITY', 'y')]
698 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_PTR_AUTH', 'y')]
699 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_BTI', 'y')]
700 if arch in ('ARM', 'X86_32'):
701 l += [KconfigCheck('harden_userspace', 'defconfig', 'VMSPLIT_3G', 'y')]
702 if arch in ('X86_64', 'ARM64'):
703 l += [KconfigCheck('harden_userspace', 'clipos', 'ARCH_MMAP_RND_BITS', '32')]
704 if arch in ('X86_32', 'ARM'):
705 l += [KconfigCheck('harden_userspace', 'my', 'ARCH_MMAP_RND_BITS', '16')]
708 def add_cmdline_checks(l, arch):
709 # Calling the CmdlineCheck class constructor:
710 # CmdlineCheck(reason, decision, name, expected)
712 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
713 # when the tool doesn't check the cmdline.
715 # [!] Make sure that values of the options in CmdlineChecks need normalization.
716 # For more info see normalize_cmdline_options().
718 # A common pattern for checking the 'param_x' cmdline parameter
719 # that __overrides__ the 'PARAM_X_DEFAULT' kconfig option:
720 # l += [OR(CmdlineCheck(reason, decision, 'param_x', '1'),
721 # AND(KconfigCheck(reason, decision, 'PARAM_X_DEFAULT_ON', 'y'),
722 # CmdlineCheck(reason, decision, 'param_x, 'is not set')))]
724 # Here we don't check the kconfig options or minimal kernel version
725 # required for the cmdline parameters. That would make the checks
726 # very complex and not give a 100% guarantee anyway.
728 # 'self_protection', 'defconfig'
729 l += [CmdlineCheck('self_protection', 'defconfig', 'nosmep', 'is not set')]
730 l += [CmdlineCheck('self_protection', 'defconfig', 'nosmap', 'is not set')]
731 l += [CmdlineCheck('self_protection', 'defconfig', 'nokaslr', 'is not set')]
732 l += [CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set')]
733 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v1', 'is not set')]
734 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v2', 'is not set')]
735 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not off'),
736 CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not set'))]
737 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spectre_v2', 'is not off'),
738 CmdlineCheck('self_protection', 'defconfig', 'spectre_v2', 'is not set'))]
740 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', 'full'),
741 AND(KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y'),
742 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set')))]
744 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', '1'),
745 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set'))]
747 # 'self_protection', 'kspp'
748 l += [CmdlineCheck('self_protection', 'kspp', 'nosmt', 'is present')]
749 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', '1'),
750 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y'),
751 CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', 'is not set')))]
752 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_free', '1'),
753 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
754 CmdlineCheck('self_protection', 'kspp', 'init_on_free', 'is not set')),
755 AND(CmdlineCheck('self_protection', 'kspp', 'page_poison', '1'),
756 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'),
757 CmdlineCheck('self_protection', 'kspp', 'slub_debug', 'P')))]
758 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_nomerge', 'is present'),
759 AND(KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set'),
760 CmdlineCheck('self_protection', 'kspp', 'slab_merge', 'is not set')))]
761 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.strict', '1'),
762 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y'),
763 CmdlineCheck('self_protection', 'kspp', 'iommu.strict', 'is not set')))]
764 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', '0'),
765 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set'),
766 CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', 'is not set')))]
767 # The cmdline checks compatible with the kconfig recommendations of the KSPP project...
768 l += [OR(CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', '1'),
769 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y'),
770 CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', 'is not set')))]
771 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', '0'),
772 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
773 CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', 'is not set')))]
775 if arch in ('X86_64', 'ARM64', 'X86_32'):
776 l += [OR(CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', '1'),
777 AND(KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y'),
778 CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', 'is not set')))]
779 if arch in ('X86_64', 'X86_32'):
780 l += [AND(CmdlineCheck('self_protection', 'kspp', 'pti', 'on'),
781 CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set'))]
783 # 'self_protection', 'clipos'
784 l += [CmdlineCheck('self_protection', 'clipos', 'page_alloc.shuffle', '1')]
786 # 'cut_attack_surface', 'kspp'
788 l += [OR(CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'none'),
789 AND(KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y'),
790 CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'is not set')))]
792 # 'cut_attack_surface', 'grsec'
793 # The cmdline checks compatible with the kconfig options disabled by grsecurity...
794 l += [OR(CmdlineCheck('cut_attack_surface', 'grsec', 'debugfs', 'off'),
795 KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set'))] # ... the end
798 def print_unknown_options(checklist, parsed_options):
802 if o1.type != 'complex':
803 known_options.append(o1.name)
806 if o2.type != 'complex':
807 if hasattr(o2, 'name'):
808 known_options.append(o2.name)
811 assert(o3.type != 'complex'), \
812 'unexpected ComplexOptCheck inside {}'.format(o2.name)
813 if hasattr(o3, 'name'):
814 known_options.append(o3.name)
816 for option, value in parsed_options.items():
817 if option not in known_options:
818 print('[?] No check for option {} ({})'.format(option, value))
821 def print_checklist(mode, checklist, with_results):
825 output.append(o.json_dump(with_results))
826 print(json.dumps(output))
833 print('=' * sep_line_len)
834 print('{:^40}|{:^7}|{:^12}|{:^10}|{:^18}'.format('option name', 'type', 'desired val', 'decision', 'reason'), end='')
836 print('| {}'.format('check result'), end='')
838 print('=' * sep_line_len)
841 for opt in checklist:
843 if mode == 'show_ok':
844 if not opt.result.startswith('OK'):
846 if mode == 'show_fail':
847 if not opt.result.startswith('FAIL'):
849 opt.table_print(mode, with_results)
851 if mode == 'verbose':
852 print('-' * sep_line_len)
857 fail_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), checklist)))
859 ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), checklist)))
861 if mode == 'show_ok':
862 fail_suppressed = ' (suppressed in output)'
863 if mode == 'show_fail':
864 ok_suppressed = ' (suppressed in output)'
866 print('[+] Config check is finished: \'OK\' - {}{} / \'FAIL\' - {}{}'.format(ok_count, ok_suppressed, fail_count, fail_suppressed))
869 def populate_simple_opt_with_data(opt, data, data_type):
870 assert(opt.type != 'complex'), \
871 'unexpected ComplexOptCheck "{}"'.format(opt.name)
872 assert(opt.type in SIMPLE_OPTION_TYPES), \
873 'invalid opt type "{}"'.format(opt.type)
874 assert(data_type in SIMPLE_OPTION_TYPES), \
875 'invalid data type "{}"'.format(data_type)
877 if data_type != opt.type:
880 if data_type in ('kconfig', 'cmdline'):
881 opt.state = data.get(opt.name, None)
883 assert(data_type == 'version'), \
884 'unexpected data type "{}"'.format(data_type)
888 def populate_opt_with_data(opt, data, data_type):
889 if opt.type == 'complex':
891 if o.type == 'complex':
892 # Recursion for nested ComplexOptCheck objects
893 populate_opt_with_data(o, data, data_type)
895 populate_simple_opt_with_data(o, data, data_type)
897 assert(opt.type in ('kconfig', 'cmdline')), \
898 'bad type "{}" for a simple check'.format(opt.type)
899 populate_simple_opt_with_data(opt, data, data_type)
902 def populate_with_data(checklist, data, data_type):
903 for opt in checklist:
904 populate_opt_with_data(opt, data, data_type)
907 def perform_checks(checklist):
908 for opt in checklist:
912 def parse_kconfig_file(parsed_options, fname):
913 with open(fname, 'r') as f:
914 opt_is_on = re.compile("CONFIG_[a-zA-Z0-9_]*=[a-zA-Z0-9_\"]*")
915 opt_is_off = re.compile("# CONFIG_[a-zA-Z0-9_]* is not set")
917 for line in f.readlines():
922 if opt_is_on.match(line):
923 option, value = line.split('=', 1)
924 if value == 'is not set':
925 sys.exit('[!] ERROR: bad enabled kconfig option "{}"'.format(line))
926 elif opt_is_off.match(line):
927 option, value = line[2:].split(' ', 1)
928 if value != 'is not set':
929 sys.exit('[!] ERROR: bad disabled kconfig option "{}"'.format(line))
931 if option in parsed_options:
932 sys.exit('[!] ERROR: kconfig option "{}" exists multiple times'.format(line))
935 parsed_options[option] = value
938 def normalize_cmdline_options(option, value):
939 # Don't normalize the cmdline option values if
940 # the Linux kernel doesn't use kstrtobool() for them
942 # See pti_check_boottime_disable() in linux/arch/x86/mm/pti.c
944 if option == 'spectre_v2':
945 # See spectre_v2_parse_cmdline() in linux/arch/x86/kernel/cpu/bugs.c
947 if option == 'debugfs':
948 # See debugfs_kernel() in fs/debugfs/inode.c
950 if option == 'mitigations':
951 # See mitigations_parse_cmdline() in linux/kernel/cpu.c
954 # Implement a limited part of the kstrtobool() logic
955 if value in ('1', 'on', 'On', 'ON', 'y', 'Y', 'yes', 'Yes', 'YES'):
957 if value in ('0', 'off', 'Off', 'OFF', 'n', 'N', 'no', 'No', 'NO'):
960 # Preserve unique values
964 def parse_cmdline_file(parsed_options, fname):
965 with open(fname, 'r') as f:
971 sys.exit('[!] ERROR: more than one line in "{}"'.format(fname))
975 name, value = opt.split('=', 1)
978 value = '' # '' is not None
979 value = normalize_cmdline_options(name, value)
980 parsed_options[name] = value
986 # - reporting about unknown kernel options in the kconfig
987 # - verbose printing of ComplexOptCheck items
988 # * json mode for printing the results in JSON format
989 report_modes = ['verbose', 'json', 'show_ok', 'show_fail']
990 supported_archs = ['X86_64', 'X86_32', 'ARM64', 'ARM']
991 parser = ArgumentParser(prog='kconfig-hardened-check',
992 description='A tool for checking the security hardening options of the Linux kernel')
993 parser.add_argument('--version', action='version', version='%(prog)s ' + __version__)
994 parser.add_argument('-p', '--print', choices=supported_archs,
995 help='print security hardening preferences for the selected architecture')
996 parser.add_argument('-c', '--config',
997 help='check the kernel kconfig file against these preferences')
998 parser.add_argument('-l', '--cmdline',
999 help='check the kernel cmdline file against these preferences')
1000 parser.add_argument('-m', '--mode', choices=report_modes,
1001 help='choose the report mode')
1002 args = parser.parse_args()
1008 print('[+] Special report mode: {}'.format(mode))
1010 config_checklist = []
1014 sys.exit('[!] ERROR: --config and --print can\'t be used together')
1017 print('[+] Kconfig file to check: {}'.format(args.config))
1019 print('[+] Kernel cmdline file to check: {}'.format(args.cmdline))
1021 arch, msg = detect_arch(args.config, supported_archs)
1023 sys.exit('[!] ERROR: {}'.format(msg))
1025 print('[+] Detected architecture: {}'.format(arch))
1027 kernel_version, msg = detect_kernel_version(args.config)
1028 if not kernel_version:
1029 sys.exit('[!] ERROR: {}'.format(msg))
1031 print('[+] Detected kernel version: {}.{}'.format(kernel_version[0], kernel_version[1]))
1033 compiler, msg = detect_compiler(args.config)
1036 print('[+] Detected compiler: {}'.format(compiler))
1038 print('[-] Can\'t detect the compiler: {}'.format(msg))
1040 # add relevant kconfig checks to the checklist
1041 add_kconfig_checks(config_checklist, arch)
1044 # add relevant cmdline checks to the checklist
1045 add_cmdline_checks(config_checklist, arch)
1047 # populate the checklist with the parsed kconfig data
1048 parsed_kconfig_options = OrderedDict()
1049 parse_kconfig_file(parsed_kconfig_options, args.config)
1050 populate_with_data(config_checklist, parsed_kconfig_options, 'kconfig')
1051 populate_with_data(config_checklist, kernel_version, 'version')
1054 # populate the checklist with the parsed kconfig data
1055 parsed_cmdline_options = OrderedDict()
1056 parse_cmdline_file(parsed_cmdline_options, args.cmdline)
1057 populate_with_data(config_checklist, parsed_cmdline_options, 'cmdline')
1059 # now everything is ready for performing the checks
1060 perform_checks(config_checklist)
1062 # finally print the results
1063 if mode == 'verbose':
1064 print_unknown_options(config_checklist, parsed_kconfig_options)
1065 print_checklist(mode, config_checklist, True)
1069 sys.exit('[!] ERROR: checking cmdline doesn\'t work without checking kconfig')
1072 if mode in ('show_ok', 'show_fail'):
1073 sys.exit('[!] ERROR: wrong mode "{}" for --print'.format(mode))
1075 add_kconfig_checks(config_checklist, arch)
1076 add_cmdline_checks(config_checklist, arch)
1078 print('[+] Printing kernel security hardening preferences for {}...'.format(arch))
1079 print_checklist(mode, config_checklist, False)