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 # Constructor without the 'expected' parameter is for option presence checks (any value is OK)
78 def __init__(self, reason, decision, name, expected=None):
79 assert(name and name == name.strip() and len(name.split()) == 1), \
80 'invalid name "{}" for {}'.format(name, self.__class__.__name__)
83 assert(decision and decision == decision.strip() and len(decision.split()) == 1), \
84 'invalid decision "{}" for "{}" check'.format(decision, name)
85 self.decision = decision
87 assert(reason and reason == reason.strip() and len(reason.split()) == 1), \
88 'invalid reason "{}" for "{}" check'.format(reason, name)
92 assert(expected == expected.strip()), \
93 'invalid expected value "{}" for "{}" check (1)'.format(expected, name)
94 val_len = len(expected.split())
96 assert(expected == 'is not set' or expected == 'is not off'), \
97 'invalid expected value "{}" for "{}" check (2)'.format(expected, name)
99 assert(val_len == 1), \
100 'invalid expected value "{}" for "{}" check (3)'.format(expected, name)
101 self.expected = expected
111 # handle the option presence check
112 if self.expected is None:
113 if self.state is None:
114 self.result = 'FAIL: is not present'
116 self.result = 'OK: is present'
119 # handle the 'is not off' option check
120 if self.expected == 'is not off':
121 if self.state == 'off':
122 self.result = 'FAIL: is off'
123 elif self.state is None:
124 self.result = 'FAIL: is off, not found'
126 self.result = 'OK: is not off, "' + self.state + '"'
129 # handle the option value check
130 if self.expected == self.state:
132 elif self.state is None:
133 if self.expected == 'is not set':
134 self.result = 'OK: is not found'
136 self.result = 'FAIL: is not found'
138 self.result = 'FAIL: "' + self.state + '"'
140 def table_print(self, _mode, with_results):
141 if self.expected is None:
144 expected = self.expected
145 print('{:<40}|{:^7}|{:^12}|{:^10}|{:^18}'.format(self.name, self.type, expected, self.decision, self.reason), end='')
147 print('| {}'.format(self.result), end='')
149 def json_dump(self, with_results):
150 dump = [self.name, self.type, self.expected, self.decision, self.reason]
152 dump.append(self.result)
156 class KconfigCheck(OptCheck):
157 def __init__(self, *args, **kwargs):
158 super().__init__(*args, **kwargs)
159 self.name = 'CONFIG_' + self.name
166 class CmdlineCheck(OptCheck):
173 def __init__(self, ver_expected):
174 assert(ver_expected and isinstance(ver_expected, tuple) and len(ver_expected) == 2), \
175 'invalid version "{}" for VersionCheck'.format(ver_expected)
176 self.ver_expected = ver_expected
185 if self.ver[0] > self.ver_expected[0]:
186 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
188 if self.ver[0] < self.ver_expected[0]:
189 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
191 if self.ver[1] >= self.ver_expected[1]:
192 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
194 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
196 def table_print(self, _mode, with_results):
197 ver_req = 'kernel version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
198 print('{:<91}'.format(ver_req), end='')
200 print('| {}'.format(self.result), end='')
203 class ComplexOptCheck:
204 def __init__(self, *opts):
207 'empty {} check'.format(self.__class__.__name__)
208 assert(len(self.opts) != 1), \
209 'useless {} check: {}'.format(self.__class__.__name__, opts)
210 assert(isinstance(opts[0], (KconfigCheck, CmdlineCheck))), \
211 'invalid {} check: {}'.format(self.__class__.__name__, opts)
220 return self.opts[0].name
224 return self.opts[0].expected
226 def table_print(self, mode, with_results):
227 if mode == 'verbose':
228 print(' {:87}'.format('<<< ' + self.__class__.__name__ + ' >>>'), end='')
230 print('| {}'.format(self.result), end='')
233 o.table_print(mode, with_results)
236 o.table_print(mode, False)
238 print('| {}'.format(self.result), end='')
240 def json_dump(self, with_results):
241 dump = self.opts[0].json_dump(False)
243 dump.append(self.result)
247 class OR(ComplexOptCheck):
248 # self.opts[0] is the option that this OR-check is about.
250 # OR(<X_is_hardened>, <X_is_disabled>)
251 # OR(<X_is_hardened>, <old_X_is_hardened>)
253 for i, opt in enumerate(self.opts):
255 if opt.result.startswith('OK'):
256 self.result = opt.result
257 # Add more info for additional checks:
259 if opt.result == 'OK':
260 self.result = 'OK: {} is "{}"'.format(opt.name, opt.expected)
261 elif opt.result == 'OK: is not found':
262 self.result = 'OK: {} is not found'.format(opt.name)
263 elif opt.result == 'OK: is present':
264 self.result = 'OK: {} is present'.format(opt.name)
265 elif opt.result.startswith('OK: is not off'):
266 self.result = 'OK: {} is not off'.format(opt.name)
268 # VersionCheck provides enough info
269 assert(opt.result.startswith('OK: version')), \
270 'unexpected OK description "{}"'.format(opt.result)
272 self.result = self.opts[0].result
275 class AND(ComplexOptCheck):
276 # self.opts[0] is the option that this AND-check is about.
278 # AND(<suboption>, <main_option>)
279 # Suboption is not checked if checking of the main_option is failed.
280 # AND(<X_is_disabled>, <old_X_is_disabled>)
282 for i, opt in reversed(list(enumerate(self.opts))):
285 self.result = opt.result
287 if not opt.result.startswith('OK'):
288 # This FAIL is caused by additional checks,
289 # and not by the main option that this AND-check is about.
290 # Describe the reason of the FAIL.
291 if opt.result.startswith('FAIL: \"') or opt.result == 'FAIL: is not found':
292 self.result = 'FAIL: {} is not "{}"'.format(opt.name, opt.expected)
293 elif opt.result == 'FAIL: is not present':
294 self.result = 'FAIL: {} is not present'.format(opt.name)
295 elif opt.result == 'FAIL: is off':
296 self.result = 'FAIL: {} is off'.format(opt.name)
297 elif opt.result == 'FAIL: is off, not found':
298 self.result = 'FAIL: {} is off, not found'.format(opt.name)
300 # VersionCheck provides enough info
301 self.result = opt.result
302 assert(opt.result.startswith('FAIL: version')), \
303 'unexpected FAIL description "{}"'.format(opt.result)
307 def detect_arch(fname, archs):
308 with open(fname, 'r') as f:
309 arch_pattern = re.compile("CONFIG_[a-zA-Z0-9_]*=y")
311 for line in f.readlines():
312 if arch_pattern.match(line):
313 option, _ = line[7:].split('=', 1)
318 return None, 'more than one supported architecture is detected'
320 return None, 'failed to detect architecture'
324 def detect_kernel_version(fname):
325 with open(fname, 'r') as f:
326 ver_pattern = re.compile("# Linux/.* Kernel Configuration")
327 for line in f.readlines():
328 if ver_pattern.match(line):
332 ver_numbers = ver_str.split('.')
333 if len(ver_numbers) < 3 or not ver_numbers[0].isdigit() or not ver_numbers[1].isdigit():
334 msg = 'failed to parse the version "' + ver_str + '"'
336 return (int(ver_numbers[0]), int(ver_numbers[1])), None
337 return None, 'no kernel version detected'
340 def detect_compiler(fname):
343 with open(fname, 'r') as f:
344 gcc_version_pattern = re.compile("CONFIG_GCC_VERSION=[0-9]*")
345 clang_version_pattern = re.compile("CONFIG_CLANG_VERSION=[0-9]*")
346 for line in f.readlines():
347 if gcc_version_pattern.match(line):
348 gcc_version = line[19:-1]
349 if clang_version_pattern.match(line):
350 clang_version = line[21:-1]
351 if not gcc_version or not clang_version:
352 return None, 'no CONFIG_GCC_VERSION or CONFIG_CLANG_VERSION'
353 if gcc_version == '0' and clang_version != '0':
354 return 'CLANG ' + clang_version, 'OK'
355 if gcc_version != '0' and clang_version == '0':
356 return 'GCC ' + gcc_version, 'OK'
357 sys.exit('[!] ERROR: invalid GCC_VERSION and CLANG_VERSION: {} {}'.format(gcc_version, clang_version))
360 def add_kconfig_checks(l, arch):
361 # Calling the KconfigCheck class constructor:
362 # KconfigCheck(reason, decision, name, expected)
364 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
365 # when the tool doesn't check the cmdline.
367 efi_not_set = KconfigCheck('-', '-', 'EFI', 'is not set')
368 cc_is_gcc = KconfigCheck('-', '-', 'CC_IS_GCC', 'y') # exists since v4.18
369 cc_is_clang = KconfigCheck('-', '-', 'CC_IS_CLANG', 'y') # exists since v4.18
371 modules_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'MODULES', 'is not set')
372 devmem_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'DEVMEM', 'is not set') # refers to LOCKDOWN
373 bpf_syscall_not_set = KconfigCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set') # refers to LOCKDOWN
375 # 'self_protection', 'defconfig'
376 l += [KconfigCheck('self_protection', 'defconfig', 'BUG', 'y')]
377 l += [KconfigCheck('self_protection', 'defconfig', 'SLUB_DEBUG', 'y')]
378 gcc_plugins_support_is_set = KconfigCheck('self_protection', 'defconfig', 'GCC_PLUGINS', 'y')
379 l += [gcc_plugins_support_is_set]
380 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR', 'y'),
381 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR', 'y'),
382 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_REGULAR', 'y'),
383 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_AUTO', 'y'),
384 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
385 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_STRONG', 'y'),
386 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
387 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_KERNEL_RWX', 'y'),
388 KconfigCheck('self_protection', 'defconfig', 'DEBUG_RODATA', 'y'))] # before v4.11
389 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_MODULE_RWX', 'y'),
390 KconfigCheck('self_protection', 'defconfig', 'DEBUG_SET_MODULE_RONX', 'y'),
391 modules_not_set)] # DEBUG_SET_MODULE_RONX was before v4.11
392 l += [OR(KconfigCheck('self_protection', 'defconfig', 'REFCOUNT_FULL', 'y'),
393 VersionCheck((5, 5)))] # REFCOUNT_FULL is enabled by default since v5.5
394 l += [KconfigCheck('self_protection', 'defconfig', 'THREAD_INFO_IN_TASK', 'y')]
395 iommu_support_is_set = KconfigCheck('self_protection', 'defconfig', 'IOMMU_SUPPORT', 'y')
396 l += [iommu_support_is_set] # is needed for mitigating DMA attacks
397 if arch in ('X86_64', 'ARM64', 'X86_32'):
398 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y')]
399 if arch in ('X86_64', 'ARM64'):
400 l += [KconfigCheck('self_protection', 'defconfig', 'VMAP_STACK', 'y')]
401 if arch in ('X86_64', 'X86_32'):
402 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE', 'y')]
403 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE_INTEL', 'y')]
404 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE_AMD', 'y')]
405 l += [KconfigCheck('self_protection', 'defconfig', 'MICROCODE', 'y')] # is needed for mitigating CPU bugs
406 l += [KconfigCheck('self_protection', 'defconfig', 'RETPOLINE', 'y')]
407 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_SMAP', 'y'),
408 VersionCheck((5, 19)))] # X86_SMAP is enabled by default since v5.19
409 l += [KconfigCheck('self_protection', 'defconfig', 'SYN_COOKIES', 'y')] # another reason?
410 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_UMIP', 'y'),
411 KconfigCheck('self_protection', 'defconfig', 'X86_INTEL_UMIP', 'y'))]
412 if arch in ('ARM64', 'ARM'):
413 l += [KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_PER_TASK', 'y')]
415 l += [KconfigCheck('self_protection', 'defconfig', 'PAGE_TABLE_ISOLATION', 'y')]
416 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MEMORY', 'y')]
417 l += [AND(KconfigCheck('self_protection', 'defconfig', 'INTEL_IOMMU', 'y'),
418 iommu_support_is_set)]
419 l += [AND(KconfigCheck('self_protection', 'defconfig', 'AMD_IOMMU', 'y'),
420 iommu_support_is_set)]
422 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PAN', 'y')]
423 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_EPAN', 'y')]
424 l += [KconfigCheck('self_protection', 'defconfig', 'UNMAP_KERNEL_AT_EL0', 'y')]
425 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_E0PD', 'y')]
426 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_EL2_VECTORS', 'y'),
427 AND(KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y'),
428 VersionCheck((5, 9))))] # HARDEN_EL2_VECTORS was included in RANDOMIZE_BASE in v5.9
429 l += [KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y')]
430 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PTR_AUTH_KERNEL', 'y')]
431 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_BTI_KERNEL', 'y')]
432 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y'),
433 VersionCheck((5, 10)))] # HARDEN_BRANCH_PREDICTOR is enabled by default since v5.10
434 l += [KconfigCheck('self_protection', 'defconfig', 'MITIGATE_SPECTRE_BRANCH_HISTORY', 'y')]
435 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_MTE', 'y')]
436 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MODULE_REGION_FULL', 'y')]
438 l += [KconfigCheck('self_protection', 'defconfig', 'CPU_SW_DOMAIN_PAN', 'y')]
439 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y')]
440 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_HISTORY', 'y')]
442 # 'self_protection', 'kspp'
443 l += [KconfigCheck('self_protection', 'kspp', 'BUG_ON_DATA_CORRUPTION', 'y')]
444 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_WX', 'y')]
445 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_STACK_END_CHECK', 'y')]
446 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_HARDENED', 'y')]
447 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_RANDOM', 'y')]
448 l += [KconfigCheck('self_protection', 'kspp', 'SHUFFLE_PAGE_ALLOCATOR', 'y')]
449 l += [KconfigCheck('self_protection', 'kspp', 'FORTIFY_SOURCE', 'y')]
450 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_LIST', 'y')]
451 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_VIRTUAL', 'y')]
452 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_SG', 'y')]
453 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_CREDENTIALS', 'y')]
454 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_NOTIFIERS', 'y')]
455 l += [KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y')]
456 l += [AND(KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_LATENT_ENTROPY', 'y'),
457 gcc_plugins_support_is_set)]
458 l += [KconfigCheck('self_protection', 'kspp', 'KFENCE', 'y')]
459 l += [KconfigCheck('self_protection', 'kspp', 'WERROR', 'y')]
460 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y')]
461 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set')] # true if IOMMU_DEFAULT_DMA_STRICT is set
462 l += [KconfigCheck('self_protection', 'kspp', 'ZERO_CALL_USED_REGS', 'y')]
463 l += [KconfigCheck('self_protection', 'kspp', 'HW_RANDOM_TPM', 'y')]
464 l += [KconfigCheck('self_protection', 'kspp', 'STATIC_USERMODEHELPER', 'y')] # needs userspace support
465 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_CORE', 'y')]
466 randstruct_is_set = OR(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_FULL', 'y'),
467 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT', 'y'))
468 l += [randstruct_is_set]
469 l += [AND(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_PERFORMANCE', 'is not set'),
470 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set'),
472 hardened_usercopy_is_set = KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y')
473 l += [hardened_usercopy_is_set]
474 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
475 hardened_usercopy_is_set)]
476 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_PAGESPAN', 'is not set'),
477 hardened_usercopy_is_set)]
478 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG', 'y'),
480 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_ALL', 'y'),
482 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_SHA512', 'y'),
484 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_FORCE', 'y'),
485 modules_not_set)] # refers to LOCKDOWN
486 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_STACK_ALL_ZERO', 'y'),
487 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y'))]
488 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
489 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'))]
490 # CONFIG_INIT_ON_FREE_DEFAULT_ON was added in v5.3.
491 # CONFIG_PAGE_POISONING_ZERO was removed in v5.11.
492 # Starting from v5.11 CONFIG_PAGE_POISONING unconditionally checks
493 # the 0xAA poison pattern on allocation.
494 # That brings higher performance penalty.
495 l += [OR(KconfigCheck('self_protection', 'kspp', 'EFI_DISABLE_PCI_DMA', 'y'),
497 l += [OR(KconfigCheck('self_protection', 'kspp', 'RESET_ATTACK_MITIGATION', 'y'),
498 efi_not_set)] # needs userspace support (systemd)
499 ubsan_bounds_is_set = KconfigCheck('self_protection', 'kspp', 'UBSAN_BOUNDS', 'y')
500 l += [ubsan_bounds_is_set]
501 l += [OR(KconfigCheck('self_protection', 'kspp', 'UBSAN_LOCAL_BOUNDS', 'y'),
502 AND(ubsan_bounds_is_set,
504 l += [AND(KconfigCheck('self_protection', 'kspp', 'UBSAN_TRAP', 'y'),
506 KconfigCheck('self_protection', 'kspp', 'UBSAN_SHIFT', 'is not set'),
507 KconfigCheck('self_protection', 'kspp', 'UBSAN_DIV_ZERO', 'is not set'),
508 KconfigCheck('self_protection', 'kspp', 'UBSAN_UNREACHABLE', 'is not set'),
509 KconfigCheck('self_protection', 'kspp', 'UBSAN_BOOL', 'is not set'),
510 KconfigCheck('self_protection', 'kspp', 'UBSAN_ENUM', 'is not set'),
511 KconfigCheck('self_protection', 'kspp', 'UBSAN_ALIGNMENT', 'is not set'))] # only array index bounds checking with traps
512 if arch in ('X86_64', 'ARM64', 'X86_32'):
513 l += [AND(KconfigCheck('self_protection', 'kspp', 'UBSAN_SANITIZE_ALL', 'y'),
514 ubsan_bounds_is_set)] # ARCH_HAS_UBSAN_SANITIZE_ALL is not enabled for ARM
515 stackleak_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STACKLEAK', 'y')
516 l += [AND(stackleak_is_set, gcc_plugins_support_is_set)]
517 l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_METRICS', 'is not set'),
519 gcc_plugins_support_is_set)]
520 l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_RUNTIME_DISABLE', 'is not set'),
522 gcc_plugins_support_is_set)]
523 l += [KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y')]
524 if arch in ('X86_64', 'ARM64'):
525 cfi_clang_is_set = KconfigCheck('self_protection', 'kspp', 'CFI_CLANG', 'y')
526 l += [cfi_clang_is_set]
527 l += [AND(KconfigCheck('self_protection', 'kspp', 'CFI_PERMISSIVE', 'is not set'),
529 if arch in ('X86_64', 'X86_32'):
530 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '65536')]
531 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU_DEFAULT_ON', 'y'),
532 iommu_support_is_set)]
533 if arch in ('ARM64', 'ARM'):
534 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '32768')]
535 l += [KconfigCheck('self_protection', 'kspp', 'SYN_COOKIES', 'y')] # another reason?
537 l += [KconfigCheck('self_protection', 'kspp', 'SLS', 'y')] # vs CVE-2021-26341 in Straight-Line-Speculation
538 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU_SVM', 'y'),
539 iommu_support_is_set)]
540 l += [AND(KconfigCheck('self_protection', 'kspp', 'AMD_IOMMU_V2', 'y'),
541 iommu_support_is_set)]
543 l += [KconfigCheck('self_protection', 'kspp', 'ARM64_SW_TTBR0_PAN', 'y')]
544 l += [KconfigCheck('self_protection', 'kspp', 'SHADOW_CALL_STACK', 'y')]
545 l += [KconfigCheck('self_protection', 'kspp', 'KASAN_HW_TAGS', 'y')]
547 l += [KconfigCheck('self_protection', 'kspp', 'PAGE_TABLE_ISOLATION', 'y')]
548 l += [KconfigCheck('self_protection', 'kspp', 'HIGHMEM64G', 'y')]
549 l += [KconfigCheck('self_protection', 'kspp', 'X86_PAE', 'y')]
550 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU', 'y'),
551 iommu_support_is_set)]
553 # 'self_protection', 'clipos'
554 l += [KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set')]
557 if arch in ('X86_64', 'ARM64', 'X86_32'):
558 l += [KconfigCheck('security_policy', 'defconfig', 'SECURITY', 'y')] # and choose your favourite LSM
560 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY', 'y')] # and choose your favourite LSM
561 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_YAMA', 'y')]
562 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LANDLOCK', 'y')]
563 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DISABLE', 'is not set')]
564 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_BOOTPARAM', 'is not set')]
565 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DEVELOP', 'is not set')]
566 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LOCKDOWN_LSM', 'y')]
567 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LOCKDOWN_LSM_EARLY', 'y')]
568 l += [KconfigCheck('security_policy', 'kspp', 'LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y')]
569 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_WRITABLE_HOOKS', 'is not set')] # refers to SECURITY_SELINUX_DISABLE
571 # 'cut_attack_surface', 'defconfig'
572 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'BPF_UNPRIV_DEFAULT_OFF', 'y'),
573 bpf_syscall_not_set)] # see unprivileged_bpf_disabled
574 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP', 'y')]
575 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP_FILTER', 'y')]
576 if arch in ('X86_64', 'ARM64', 'X86_32'):
577 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'STRICT_DEVMEM', 'y'),
578 devmem_not_set)] # refers to LOCKDOWN
580 # 'cut_attack_surface', 'kspp'
581 l += [KconfigCheck('cut_attack_surface', 'kspp', 'SECURITY_DMESG_RESTRICT', 'y')]
582 l += [KconfigCheck('cut_attack_surface', 'kspp', 'ACPI_CUSTOM_METHOD', 'is not set')] # refers to LOCKDOWN
583 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_BRK', 'is not set')]
584 l += [KconfigCheck('cut_attack_surface', 'kspp', 'DEVKMEM', 'is not set')] # refers to LOCKDOWN
585 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_VDSO', 'is not set')]
586 l += [KconfigCheck('cut_attack_surface', 'kspp', 'BINFMT_MISC', 'is not set')]
587 l += [KconfigCheck('cut_attack_surface', 'kspp', 'INET_DIAG', 'is not set')]
588 l += [KconfigCheck('cut_attack_surface', 'kspp', 'KEXEC', 'is not set')] # refers to LOCKDOWN
589 l += [KconfigCheck('cut_attack_surface', 'kspp', 'PROC_KCORE', 'is not set')] # refers to LOCKDOWN
590 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_PTYS', 'is not set')]
591 l += [KconfigCheck('cut_attack_surface', 'kspp', 'HIBERNATION', 'is not set')] # refers to LOCKDOWN
592 l += [KconfigCheck('cut_attack_surface', 'kspp', 'IA32_EMULATION', 'is not set')]
593 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_X32', 'is not set')]
594 l += [KconfigCheck('cut_attack_surface', 'kspp', 'MODIFY_LDT_SYSCALL', 'is not set')]
595 l += [KconfigCheck('cut_attack_surface', 'kspp', 'OABI_COMPAT', 'is not set')]
596 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_MSR', 'is not set')] # refers to LOCKDOWN
597 l += [modules_not_set]
598 l += [devmem_not_set]
599 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'IO_STRICT_DEVMEM', 'y'),
600 devmem_not_set)] # refers to LOCKDOWN
601 l += [AND(KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD', 'is not set'),
602 KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD'))] # option presence check
604 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'STRICT_DEVMEM', 'y'),
605 devmem_not_set)] # refers to LOCKDOWN
607 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y')] # 'vsyscall=none'
609 # 'cut_attack_surface', 'grsec'
610 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ZSMALLOC_STAT', 'is not set')]
611 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PAGE_OWNER', 'is not set')]
612 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_KMEMLEAK', 'is not set')]
613 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BINFMT_AOUT', 'is not set')]
614 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KPROBE_EVENTS', 'is not set')]
615 l += [KconfigCheck('cut_attack_surface', 'grsec', 'UPROBE_EVENTS', 'is not set')]
616 l += [KconfigCheck('cut_attack_surface', 'grsec', 'GENERIC_TRACER', 'is not set')] # refers to LOCKDOWN
617 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FUNCTION_TRACER', 'is not set')]
618 l += [KconfigCheck('cut_attack_surface', 'grsec', 'STACK_TRACER', 'is not set')]
619 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HIST_TRIGGERS', 'is not set')]
620 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BLK_DEV_IO_TRACE', 'is not set')]
621 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_VMCORE', 'is not set')]
622 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_PAGE_MONITOR', 'is not set')]
623 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USELIB', 'is not set')]
624 l += [KconfigCheck('cut_attack_surface', 'grsec', 'CHECKPOINT_RESTORE', 'is not set')]
625 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USERFAULTFD', 'is not set')]
626 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HWPOISON_INJECT', 'is not set')]
627 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MEM_SOFT_DIRTY', 'is not set')]
628 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEVPORT', 'is not set')] # refers to LOCKDOWN
629 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set')] # refers to LOCKDOWN
630 l += [KconfigCheck('cut_attack_surface', 'grsec', 'NOTIFIER_ERROR_INJECTION', 'is not set')]
631 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FAIL_FUTEX', 'is not set')]
632 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PUNIT_ATOM_DEBUG', 'is not set')]
633 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ACPI_CONFIGFS', 'is not set')]
634 l += [KconfigCheck('cut_attack_surface', 'grsec', 'EDAC_DEBUG', 'is not set')]
635 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DRM_I915_DEBUG', 'is not set')]
636 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BCACHE_CLOSURES_DEBUG', 'is not set')]
637 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DVB_C8SECTPFE', 'is not set')]
638 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_SLRAM', 'is not set')]
639 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_PHRAM', 'is not set')]
640 l += [KconfigCheck('cut_attack_surface', 'grsec', 'IO_URING', 'is not set')]
641 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCMP', 'is not set')]
642 l += [KconfigCheck('cut_attack_surface', 'grsec', 'RSEQ', 'is not set')]
643 l += [KconfigCheck('cut_attack_surface', 'grsec', 'LATENCYTOP', 'is not set')]
644 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCOV', 'is not set')]
645 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROVIDE_OHCI1394_DMA_INIT', 'is not set')]
646 l += [KconfigCheck('cut_attack_surface', 'grsec', 'SUNRPC_DEBUG', 'is not set')]
647 l += [AND(KconfigCheck('cut_attack_surface', 'grsec', 'PTDUMP_DEBUGFS', 'is not set'),
648 KconfigCheck('cut_attack_surface', 'grsec', 'X86_PTDUMP', 'is not set'))]
650 # 'cut_attack_surface', 'maintainer'
651 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'DRM_LEGACY', 'is not set')] # recommended by Daniel Vetter in /issues/38
652 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'FB', 'is not set')] # recommended by Daniel Vetter in /issues/38
653 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'VT', 'is not set')] # recommended by Daniel Vetter in /issues/38
654 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD', 'is not set')] # recommended by Denis Efremov in /pull/54
655 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD_RAWCMD', 'is not set')] # recommended by Denis Efremov in /pull/62
657 # 'cut_attack_surface', 'grapheneos'
658 l += [KconfigCheck('cut_attack_surface', 'grapheneos', 'AIO', 'is not set')]
660 # 'cut_attack_surface', 'clipos'
661 l += [KconfigCheck('cut_attack_surface', 'clipos', 'STAGING', 'is not set')]
662 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KSM', 'is not set')] # to prevent FLUSH+RELOAD attack
663 # l += [KconfigCheck('cut_attack_surface', 'clipos', 'IKCONFIG', 'is not set')] # no, IKCONFIG is needed for this check :)
664 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KALLSYMS', 'is not set')]
665 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_VSYSCALL_EMULATION', 'is not set')]
666 l += [KconfigCheck('cut_attack_surface', 'clipos', 'MAGIC_SYSRQ', 'is not set')]
667 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KEXEC_FILE', 'is not set')] # refers to LOCKDOWN (permissive)
668 l += [KconfigCheck('cut_attack_surface', 'clipos', 'USER_NS', 'is not set')] # user.max_user_namespaces=0
669 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_CPUID', 'is not set')]
670 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_IOPL_IOPERM', 'is not set')] # refers to LOCKDOWN
671 l += [KconfigCheck('cut_attack_surface', 'clipos', 'ACPI_TABLE_UPGRADE', 'is not set')] # refers to LOCKDOWN
672 l += [KconfigCheck('cut_attack_surface', 'clipos', 'EFI_CUSTOM_SSDT_OVERLAYS', 'is not set')]
673 l += [KconfigCheck('cut_attack_surface', 'clipos', 'COREDUMP', 'is not set')] # cut userspace attack surface
674 if arch in ('X86_64', 'X86_32'):
675 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_INTEL_TSX_MODE_OFF', 'y')] # tsx=off
677 # 'cut_attack_surface', 'lockdown'
678 l += [bpf_syscall_not_set] # refers to LOCKDOWN
679 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'EFI_TEST', 'is not set')] # refers to LOCKDOWN
680 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'MMIOTRACE_TEST', 'is not set')] # refers to LOCKDOWN
681 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'KPROBES', 'is not set')] # refers to LOCKDOWN
683 # 'cut_attack_surface', 'my'
684 l += [OR(KconfigCheck('cut_attack_surface', 'my', 'TRIM_UNUSED_KSYMS', 'y'),
686 l += [KconfigCheck('cut_attack_surface', 'my', 'MMIOTRACE', 'is not set')] # refers to LOCKDOWN (permissive)
687 l += [KconfigCheck('cut_attack_surface', 'my', 'LIVEPATCH', 'is not set')]
688 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_DCCP', 'is not set')]
689 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_SCTP', 'is not set')]
690 l += [KconfigCheck('cut_attack_surface', 'my', 'FTRACE', 'is not set')] # refers to LOCKDOWN
691 l += [KconfigCheck('cut_attack_surface', 'my', 'VIDEO_VIVID', 'is not set')]
692 l += [KconfigCheck('cut_attack_surface', 'my', 'INPUT_EVBUG', 'is not set')] # Can be used as a keylogger
693 l += [KconfigCheck('cut_attack_surface', 'my', 'KGDB', 'is not set')]
696 if arch in ('X86_64', 'ARM64', 'X86_32'):
697 l += [KconfigCheck('harden_userspace', 'defconfig', 'INTEGRITY', 'y')]
699 l += [KconfigCheck('harden_userspace', 'my', 'INTEGRITY', 'y')]
701 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_PTR_AUTH', 'y')]
702 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_BTI', 'y')]
703 if arch in ('ARM', 'X86_32'):
704 l += [KconfigCheck('harden_userspace', 'defconfig', 'VMSPLIT_3G', 'y')]
705 if arch in ('X86_64', 'ARM64'):
706 l += [KconfigCheck('harden_userspace', 'clipos', 'ARCH_MMAP_RND_BITS', '32')]
707 if arch in ('X86_32', 'ARM'):
708 l += [KconfigCheck('harden_userspace', 'my', 'ARCH_MMAP_RND_BITS', '16')]
711 def add_cmdline_checks(l, arch):
712 # Calling the CmdlineCheck class constructor:
713 # CmdlineCheck(reason, decision, name, expected)
715 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
716 # when the tool doesn't check the cmdline.
718 # [!] Make sure that values of the options in CmdlineChecks need normalization.
719 # For more info see normalize_cmdline_options().
721 # A common pattern for checking the 'param_x' cmdline parameter
722 # that __overrides__ the 'PARAM_X_DEFAULT' kconfig option:
723 # l += [OR(CmdlineCheck(reason, decision, 'param_x', '1'),
724 # AND(KconfigCheck(reason, decision, 'PARAM_X_DEFAULT_ON', 'y'),
725 # CmdlineCheck(reason, decision, 'param_x, 'is not set')))]
727 # Here we don't check the kconfig options or minimal kernel version
728 # required for the cmdline parameters. That would make the checks
729 # very complex and not give a 100% guarantee anyway.
731 # 'self_protection', 'defconfig'
732 l += [CmdlineCheck('self_protection', 'defconfig', 'nosmep', 'is not set')]
733 l += [CmdlineCheck('self_protection', 'defconfig', 'nosmap', 'is not set')]
734 l += [CmdlineCheck('self_protection', 'defconfig', 'nokaslr', 'is not set')]
735 l += [CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set')]
736 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v1', 'is not set')]
737 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v2', 'is not set')]
738 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not off'),
739 CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not set'))]
741 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', 'full'),
742 AND(KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y'),
743 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set')))]
745 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', '1'),
746 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set'))]
748 # 'self_protection', 'kspp'
749 l += [CmdlineCheck('self_protection', 'kspp', 'nosmt')] # option presence check
750 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', '1'),
751 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y'),
752 CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', 'is not set')))]
753 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_free', '1'),
754 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
755 CmdlineCheck('self_protection', 'kspp', 'init_on_free', 'is not set')),
756 AND(CmdlineCheck('self_protection', 'kspp', 'page_poison', '1'),
757 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'),
758 CmdlineCheck('self_protection', 'kspp', 'slub_debug', 'P')))]
759 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_nomerge'),
760 AND(KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set'),
761 CmdlineCheck('self_protection', 'kspp', 'slab_merge', 'is not set')))] # option presence check
762 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.strict', '1'),
763 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y'),
764 CmdlineCheck('self_protection', 'kspp', 'iommu.strict', 'is not set')))]
765 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', '0'),
766 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set'),
767 CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', 'is not set')))]
768 # The cmdline checks compatible with the kconfig recommendations of the KSPP project...
769 l += [OR(CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', '1'),
770 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y'),
771 CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', 'is not set')))]
772 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', '0'),
773 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
774 CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', 'is not set')))]
776 if arch in ('X86_64', 'ARM64', 'X86_32'):
777 l += [OR(CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', '1'),
778 AND(KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y'),
779 CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', 'is not set')))]
780 if arch in ('X86_64', 'X86_32'):
781 l += [AND(CmdlineCheck('self_protection', 'kspp', 'pti', 'on'),
782 CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set'))]
784 # 'self_protection', 'clipos'
785 l += [CmdlineCheck('self_protection', 'clipos', 'page_alloc.shuffle', '1')]
786 if arch in ('X86_64', 'X86_32'):
787 l += [AND(CmdlineCheck('self_protection', 'clipos', 'spectre_v2', 'on'),
788 CmdlineCheck('self_protection', 'defconfig', 'nospectre_v2', 'is not set'))]
790 # 'cut_attack_surface', 'kspp'
792 l += [OR(CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'none'),
793 AND(KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y'),
794 CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'is not set')))]
796 # 'cut_attack_surface', 'grsec'
797 # The cmdline checks compatible with the kconfig options disabled by grsecurity...
798 l += [OR(CmdlineCheck('cut_attack_surface', 'grsec', 'debugfs', 'off'),
799 KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set'))] # ... the end
802 def print_unknown_options(checklist, parsed_options):
806 if o1.type != 'complex':
807 known_options.append(o1.name)
810 if o2.type != 'complex':
811 if hasattr(o2, 'name'):
812 known_options.append(o2.name)
815 assert(o3.type != 'complex'), \
816 'unexpected ComplexOptCheck inside {}'.format(o2.name)
817 if hasattr(o3, 'name'):
818 known_options.append(o3.name)
820 for option, value in parsed_options.items():
821 if option not in known_options:
822 print('[?] No check for option {} ({})'.format(option, value))
825 def print_checklist(mode, checklist, with_results):
829 output.append(o.json_dump(with_results))
830 print(json.dumps(output))
837 print('=' * sep_line_len)
838 print('{:^40}|{:^7}|{:^12}|{:^10}|{:^18}'.format('option name', 'type', 'desired val', 'decision', 'reason'), end='')
840 print('| {}'.format('check result'), end='')
842 print('=' * sep_line_len)
845 for opt in checklist:
847 if mode == 'show_ok':
848 if not opt.result.startswith('OK'):
850 if mode == 'show_fail':
851 if not opt.result.startswith('FAIL'):
853 opt.table_print(mode, with_results)
855 if mode == 'verbose':
856 print('-' * sep_line_len)
861 fail_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), checklist)))
863 ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), checklist)))
865 if mode == 'show_ok':
866 fail_suppressed = ' (suppressed in output)'
867 if mode == 'show_fail':
868 ok_suppressed = ' (suppressed in output)'
870 print('[+] Config check is finished: \'OK\' - {}{} / \'FAIL\' - {}{}'.format(ok_count, ok_suppressed, fail_count, fail_suppressed))
873 def populate_simple_opt_with_data(opt, data, data_type):
874 assert(opt.type != 'complex'), \
875 'unexpected ComplexOptCheck "{}"'.format(opt.name)
876 assert(opt.type in SIMPLE_OPTION_TYPES), \
877 'invalid opt type "{}"'.format(opt.type)
878 assert(data_type in SIMPLE_OPTION_TYPES), \
879 'invalid data type "{}"'.format(data_type)
881 if data_type != opt.type:
884 if data_type in ('kconfig', 'cmdline'):
885 opt.state = data.get(opt.name, None)
887 assert(data_type == 'version'), \
888 'unexpected data type "{}"'.format(data_type)
892 def populate_opt_with_data(opt, data, data_type):
893 if opt.type == 'complex':
895 if o.type == 'complex':
896 # Recursion for nested ComplexOptCheck objects
897 populate_opt_with_data(o, data, data_type)
899 populate_simple_opt_with_data(o, data, data_type)
901 assert(opt.type in ('kconfig', 'cmdline')), \
902 'bad type "{}" for a simple check'.format(opt.type)
903 populate_simple_opt_with_data(opt, data, data_type)
906 def populate_with_data(checklist, data, data_type):
907 for opt in checklist:
908 populate_opt_with_data(opt, data, data_type)
911 def perform_checks(checklist):
912 for opt in checklist:
916 def parse_kconfig_file(parsed_options, fname):
917 with open(fname, 'r') as f:
918 opt_is_on = re.compile("CONFIG_[a-zA-Z0-9_]*=[a-zA-Z0-9_\"]*")
919 opt_is_off = re.compile("# CONFIG_[a-zA-Z0-9_]* is not set")
921 for line in f.readlines():
926 if opt_is_on.match(line):
927 option, value = line.split('=', 1)
928 if value == 'is not set':
929 sys.exit('[!] ERROR: bad enabled kconfig option "{}"'.format(line))
930 elif opt_is_off.match(line):
931 option, value = line[2:].split(' ', 1)
932 if value != 'is not set':
933 sys.exit('[!] ERROR: bad disabled kconfig option "{}"'.format(line))
935 if option in parsed_options:
936 sys.exit('[!] ERROR: kconfig option "{}" exists multiple times'.format(line))
939 parsed_options[option] = value
942 def normalize_cmdline_options(option, value):
943 # Don't normalize the cmdline option values if
944 # the Linux kernel doesn't use kstrtobool() for them
946 # See pti_check_boottime_disable() in linux/arch/x86/mm/pti.c
948 if option == 'spectre_v2':
949 # See spectre_v2_parse_cmdline() in linux/arch/x86/kernel/cpu/bugs.c
951 if option == 'debugfs':
952 # See debugfs_kernel() in fs/debugfs/inode.c
954 if option == 'mitigations':
955 # See mitigations_parse_cmdline() in linux/kernel/cpu.c
958 # Implement a limited part of the kstrtobool() logic
959 if value in ('1', 'on', 'On', 'ON', 'y', 'Y', 'yes', 'Yes', 'YES'):
961 if value in ('0', 'off', 'Off', 'OFF', 'n', 'N', 'no', 'No', 'NO'):
964 # Preserve unique values
968 def parse_cmdline_file(parsed_options, fname):
969 with open(fname, 'r') as f:
975 sys.exit('[!] ERROR: more than one line in "{}"'.format(fname))
979 name, value = opt.split('=', 1)
982 value = '' # '' is not None
983 value = normalize_cmdline_options(name, value)
984 parsed_options[name] = value
990 # - reporting about unknown kernel options in the kconfig
991 # - verbose printing of ComplexOptCheck items
992 # * json mode for printing the results in JSON format
993 report_modes = ['verbose', 'json', 'show_ok', 'show_fail']
994 supported_archs = ['X86_64', 'X86_32', 'ARM64', 'ARM']
995 parser = ArgumentParser(prog='kconfig-hardened-check',
996 description='A tool for checking the security hardening options of the Linux kernel')
997 parser.add_argument('--version', action='version', version='%(prog)s ' + __version__)
998 parser.add_argument('-p', '--print', choices=supported_archs,
999 help='print security hardening preferences for the selected architecture')
1000 parser.add_argument('-c', '--config',
1001 help='check the kernel kconfig file against these preferences')
1002 parser.add_argument('-l', '--cmdline',
1003 help='check the kernel cmdline file against these preferences')
1004 parser.add_argument('-m', '--mode', choices=report_modes,
1005 help='choose the report mode')
1006 args = parser.parse_args()
1012 print('[+] Special report mode: {}'.format(mode))
1014 config_checklist = []
1018 sys.exit('[!] ERROR: --config and --print can\'t be used together')
1021 print('[+] Kconfig file to check: {}'.format(args.config))
1023 print('[+] Kernel cmdline file to check: {}'.format(args.cmdline))
1025 arch, msg = detect_arch(args.config, supported_archs)
1027 sys.exit('[!] ERROR: {}'.format(msg))
1029 print('[+] Detected architecture: {}'.format(arch))
1031 kernel_version, msg = detect_kernel_version(args.config)
1032 if not kernel_version:
1033 sys.exit('[!] ERROR: {}'.format(msg))
1035 print('[+] Detected kernel version: {}.{}'.format(kernel_version[0], kernel_version[1]))
1037 compiler, msg = detect_compiler(args.config)
1040 print('[+] Detected compiler: {}'.format(compiler))
1042 print('[-] Can\'t detect the compiler: {}'.format(msg))
1044 # add relevant kconfig checks to the checklist
1045 add_kconfig_checks(config_checklist, arch)
1048 # add relevant cmdline checks to the checklist
1049 add_cmdline_checks(config_checklist, arch)
1051 # populate the checklist with the parsed kconfig data
1052 parsed_kconfig_options = OrderedDict()
1053 parse_kconfig_file(parsed_kconfig_options, args.config)
1054 populate_with_data(config_checklist, parsed_kconfig_options, 'kconfig')
1055 populate_with_data(config_checklist, kernel_version, 'version')
1058 # populate the checklist with the parsed kconfig data
1059 parsed_cmdline_options = OrderedDict()
1060 parse_cmdline_file(parsed_cmdline_options, args.cmdline)
1061 populate_with_data(config_checklist, parsed_cmdline_options, 'cmdline')
1063 # now everything is ready for performing the checks
1064 perform_checks(config_checklist)
1066 # finally print the results
1067 if mode == 'verbose':
1068 print_unknown_options(config_checklist, parsed_kconfig_options)
1069 print_checklist(mode, config_checklist, True)
1073 sys.exit('[!] ERROR: checking cmdline doesn\'t work without checking kconfig')
1076 if mode in ('show_ok', 'show_fail'):
1077 sys.exit('[!] ERROR: wrong mode "{}" for --print'.format(mode))
1079 add_kconfig_checks(config_checklist, arch)
1080 add_cmdline_checks(config_checklist, arch)
1082 print('[+] Printing kernel security hardening preferences for {}...'.format(arch))
1083 print_checklist(mode, config_checklist, False)