4 # This script helps me to check the Linux kernel Kconfig option list
5 # against my 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:
16 # page_alloc.shuffle=1
17 # iommu=force (does it help against DMA attacks?)
18 # page_poison=1 (if enabled)
23 # Mitigations of CPU vulnerabilities:
25 # mitigations=auto,nosmt
29 # spec_store_bypass_disable=on
37 # N.B. Hardening sysctls:
38 # kernel.kptr_restrict=2
39 # kernel.dmesg_restrict=1
40 # kernel.perf_event_paranoid=3
41 # kernel.kexec_load_disabled=1
42 # kernel.yama.ptrace_scope=3
43 # user.max_user_namespaces=0
44 # kernel.unprivileged_bpf_disabled=1
45 # net.core.bpf_jit_harden=2
47 # vm.unprivileged_userfaultfd=0
49 # dev.tty.ldisc_autoload=0
50 # fs.protected_symlinks=1
51 # fs.protected_hardlinks=1
52 # fs.protected_fifos=2
53 # fs.protected_regular=2
55 # kernel.modules_disabled=1
58 from argparse import ArgumentParser
59 from collections import OrderedDict
64 # - reporting about unknown kernel options in the config,
65 # - verbose printing of ComplexOptChecks (OR, AND).
68 # json_mode is for printing results in JSON format
71 supported_archs = [ 'X86_64', 'X86_32', 'ARM64', 'ARM' ]
77 def __init__(self, name, expected, decision, reason):
79 self.expected = expected
80 self.decision = decision
86 if self.expected == self.state:
88 elif self.state is None:
89 if self.expected == 'is not set':
90 self.result = 'OK: not found'
92 self.result = 'FAIL: not found'
94 self.result = 'FAIL: "' + self.state + '"'
96 if self.result.startswith('OK'):
97 return True, self.result
99 return False, self.result
103 def __init__(self, ver_expected):
104 self.ver_expected = ver_expected
108 if kernel_version[0] > self.ver_expected[0]:
109 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
110 return True, self.result
111 if kernel_version[0] < self.ver_expected[0]:
112 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
113 return False, self.result
114 if kernel_version[1] >= self.ver_expected[1]:
115 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
116 return True, self.result
118 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
119 return False, self.result
122 class ComplexOptCheck:
123 def __init__(self, *opts):
129 return self.opts[0].name
133 return self.opts[0].expected
137 return self.opts[0].state
141 return self.opts[0].decision
145 return self.opts[0].reason
148 class OR(ComplexOptCheck):
149 # self.opts[0] is the option that this OR-check is about.
151 # OR(<X_is_hardened>, <X_is_disabled>)
152 # OR(<X_is_hardened>, <X_is_hardened_old>)
156 sys.exit('[!] ERROR: invalid OR check')
158 for i, opt in enumerate(self.opts):
159 ret, msg = opt.check()
161 if i == 0 or not hasattr(opt, 'name'):
162 self.result = opt.result
164 self.result = 'OK: CONFIG_{} "{}"'.format(opt.name, opt.expected)
165 return True, self.result
166 self.result = self.opts[0].result
167 return False, self.result
170 class AND(ComplexOptCheck):
171 # self.opts[0] is the option that this AND-check is about.
172 # Use case: AND(<suboption>, <main_option>)
173 # Suboption is not checked if checking of the main_option is failed.
176 for i, opt in reversed(list(enumerate(self.opts))):
177 ret, msg = opt.check()
179 self.result = opt.result
180 return ret, self.result
182 if hasattr(opt, 'name'):
183 self.result = 'FAIL: CONFIG_{} is needed'.format(opt.name)
185 self.result = opt.result
186 return False, self.result
188 sys.exit('[!] ERROR: invalid AND check')
191 def detect_arch(fname):
192 with open(fname, 'r') as f:
193 arch_pattern = re.compile("CONFIG_[a-zA-Z0-9_]*=y")
196 print('[+] Trying to detect architecture in "{}"...'.format(fname))
197 for line in f.readlines():
198 if arch_pattern.match(line):
199 option, value = line[7:].split('=', 1)
200 if option in supported_archs:
204 return None, 'more than one supported architecture is detected'
206 return None, 'failed to detect architecture'
211 def detect_version(fname):
212 with open(fname, 'r') as f:
213 ver_pattern = re.compile("# Linux/.* Kernel Configuration")
215 print('[+] Trying to detect kernel version in "{}"...'.format(fname))
216 for line in f.readlines():
217 if ver_pattern.match(line):
220 print('[+] Found version line: "{}"'.format(line))
223 ver_numbers = ver_str.split('.')
224 if len(ver_numbers) < 3 or not ver_numbers[0].isdigit() or not ver_numbers[1].isdigit():
225 msg = 'failed to parse the version "' + ver_str + '"'
228 return (int(ver_numbers[0]), int(ver_numbers[1])), None
229 return None, 'no kernel version detected'
232 def construct_checklist(checklist, arch):
233 modules_not_set = OptCheck('MODULES', 'is not set', 'kspp', 'cut_attack_surface')
234 devmem_not_set = OptCheck('DEVMEM', 'is not set', 'kspp', 'cut_attack_surface') # refers to LOCKDOWN
236 checklist.append(OptCheck('BUG', 'y', 'defconfig', 'self_protection'))
237 checklist.append(OR(OptCheck('STRICT_KERNEL_RWX', 'y', 'defconfig', 'self_protection'), \
238 OptCheck('DEBUG_RODATA', 'y', 'defconfig', 'self_protection'))) # before v4.11
239 checklist.append(OR(OptCheck('STACKPROTECTOR_STRONG', 'y', 'defconfig', 'self_protection'), \
240 OptCheck('CC_STACKPROTECTOR_STRONG', 'y', 'defconfig', 'self_protection')))
241 checklist.append(OptCheck('SLUB_DEBUG', 'y', 'defconfig', 'self_protection'))
242 checklist.append(OR(OptCheck('STRICT_MODULE_RWX', 'y', 'defconfig', 'self_protection'), \
243 OptCheck('DEBUG_SET_MODULE_RONX', 'y', 'defconfig', 'self_protection'), \
244 modules_not_set)) # DEBUG_SET_MODULE_RONX was before v4.11
245 checklist.append(OptCheck('GCC_PLUGINS', 'y', 'defconfig', 'self_protection'))
246 checklist.append(OR(OptCheck('REFCOUNT_FULL', 'y', 'defconfig', 'self_protection'), \
247 VerCheck((5, 5)))) # REFCOUNT_FULL is enabled by default since v5.5
248 iommu_support_is_set = OptCheck('IOMMU_SUPPORT', 'y', 'defconfig', 'self_protection') # is needed for mitigating DMA attacks
249 checklist.append(iommu_support_is_set)
250 if arch == 'X86_64' or arch == 'X86_32':
251 checklist.append(OptCheck('MICROCODE', 'y', 'defconfig', 'self_protection')) # is needed for mitigating CPU bugs
252 checklist.append(OptCheck('RETPOLINE', 'y', 'defconfig', 'self_protection'))
253 checklist.append(OptCheck('X86_SMAP', 'y', 'defconfig', 'self_protection'))
254 checklist.append(OR(OptCheck('X86_UMIP', 'y', 'defconfig', 'self_protection'), \
255 OptCheck('X86_INTEL_UMIP', 'y', 'defconfig', 'self_protection')))
256 checklist.append(OptCheck('SYN_COOKIES', 'y', 'defconfig', 'self_protection')) # another reason?
258 checklist.append(OptCheck('PAGE_TABLE_ISOLATION', 'y', 'defconfig', 'self_protection'))
259 checklist.append(OptCheck('RANDOMIZE_MEMORY', 'y', 'defconfig', 'self_protection'))
260 checklist.append(AND(OptCheck('INTEL_IOMMU', 'y', 'defconfig', 'self_protection'), \
261 iommu_support_is_set))
262 checklist.append(AND(OptCheck('AMD_IOMMU', 'y', 'defconfig', 'self_protection'), \
263 iommu_support_is_set))
265 checklist.append(OptCheck('UNMAP_KERNEL_AT_EL0', 'y', 'defconfig', 'self_protection'))
266 checklist.append(OptCheck('HARDEN_EL2_VECTORS', 'y', 'defconfig', 'self_protection'))
267 checklist.append(OptCheck('RODATA_FULL_DEFAULT_ENABLED', 'y', 'defconfig', 'self_protection'))
268 if arch == 'X86_64' or arch == 'ARM64':
269 checklist.append(OptCheck('VMAP_STACK', 'y', 'defconfig', 'self_protection'))
270 if arch == 'X86_64' or arch == 'ARM64' or arch == 'X86_32':
271 checklist.append(OptCheck('RANDOMIZE_BASE', 'y', 'defconfig', 'self_protection'))
272 checklist.append(OptCheck('THREAD_INFO_IN_TASK', 'y', 'defconfig', 'self_protection'))
274 checklist.append(OptCheck('CPU_SW_DOMAIN_PAN', 'y', 'defconfig', 'self_protection'))
275 checklist.append(OptCheck('STACKPROTECTOR_PER_TASK', 'y', 'defconfig', 'self_protection'))
276 if arch == 'ARM64' or arch == 'ARM':
277 checklist.append(OptCheck('HARDEN_BRANCH_PREDICTOR', 'y', 'defconfig', 'self_protection'))
279 checklist.append(OptCheck('BUG_ON_DATA_CORRUPTION', 'y', 'kspp', 'self_protection'))
280 checklist.append(OptCheck('DEBUG_WX', 'y', 'kspp', 'self_protection'))
281 checklist.append(OptCheck('SCHED_STACK_END_CHECK', 'y', 'kspp', 'self_protection'))
282 checklist.append(OptCheck('SLAB_FREELIST_HARDENED', 'y', 'kspp', 'self_protection'))
283 checklist.append(OptCheck('SLAB_FREELIST_RANDOM', 'y', 'kspp', 'self_protection'))
284 checklist.append(OptCheck('SHUFFLE_PAGE_ALLOCATOR', 'y', 'kspp', 'self_protection'))
285 checklist.append(OptCheck('FORTIFY_SOURCE', 'y', 'kspp', 'self_protection'))
286 randstruct_is_set = OptCheck('GCC_PLUGIN_RANDSTRUCT', 'y', 'kspp', 'self_protection')
287 checklist.append(randstruct_is_set)
288 checklist.append(OptCheck('GCC_PLUGIN_LATENT_ENTROPY', 'y', 'kspp', 'self_protection'))
289 checklist.append(OptCheck('DEBUG_LIST', 'y', 'kspp', 'self_protection'))
290 checklist.append(OptCheck('DEBUG_SG', 'y', 'kspp', 'self_protection'))
291 checklist.append(OptCheck('DEBUG_CREDENTIALS', 'y', 'kspp', 'self_protection'))
292 checklist.append(OptCheck('DEBUG_NOTIFIERS', 'y', 'kspp', 'self_protection'))
293 hardened_usercopy_is_set = OptCheck('HARDENED_USERCOPY', 'y', 'kspp', 'self_protection')
294 checklist.append(hardened_usercopy_is_set)
295 checklist.append(AND(OptCheck('HARDENED_USERCOPY_FALLBACK', 'is not set', 'kspp', 'self_protection'), \
296 hardened_usercopy_is_set))
297 checklist.append(OR(OptCheck('MODULE_SIG', 'y', 'kspp', 'self_protection'), \
299 checklist.append(OR(OptCheck('MODULE_SIG_ALL', 'y', 'kspp', 'self_protection'), \
301 checklist.append(OR(OptCheck('MODULE_SIG_SHA512', 'y', 'kspp', 'self_protection'), \
303 checklist.append(OR(OptCheck('MODULE_SIG_FORCE', 'y', 'kspp', 'self_protection'), \
304 modules_not_set)) # refers to LOCKDOWN
305 checklist.append(OR(OptCheck('INIT_STACK_ALL', 'y', 'kspp', 'self_protection'), \
306 OptCheck('GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y', 'kspp', 'self_protection')))
307 checklist.append(OptCheck('INIT_ON_ALLOC_DEFAULT_ON', 'y', 'kspp', 'self_protection'))
308 checklist.append(OR(OptCheck('INIT_ON_FREE_DEFAULT_ON', 'y', 'kspp', 'self_protection'), \
309 OptCheck('PAGE_POISONING', 'y', 'kspp', 'self_protection'))) # before v5.3
310 if arch == 'X86_64' or arch == 'ARM64' or arch == 'X86_32':
311 stackleak_is_set = OptCheck('GCC_PLUGIN_STACKLEAK', 'y', 'kspp', 'self_protection')
312 checklist.append(stackleak_is_set)
313 checklist.append(AND(OptCheck('STACKLEAK_METRICS', 'is not set', 'clipos', 'self_protection'), \
315 checklist.append(AND(OptCheck('STACKLEAK_RUNTIME_DISABLE', 'is not set', 'clipos', 'self_protection'), \
317 if arch == 'X86_64' or arch == 'X86_32':
318 checklist.append(OptCheck('DEFAULT_MMAP_MIN_ADDR', '65536', 'kspp', 'self_protection'))
320 checklist.append(OptCheck('PAGE_TABLE_ISOLATION', 'y', 'kspp', 'self_protection'))
321 checklist.append(OptCheck('HIGHMEM64G', 'y', 'kspp', 'self_protection'))
322 checklist.append(OptCheck('X86_PAE', 'y', 'kspp', 'self_protection'))
324 checklist.append(OptCheck('ARM64_SW_TTBR0_PAN', 'y', 'kspp', 'self_protection'))
325 if arch == 'ARM64' or arch == 'ARM':
326 checklist.append(OptCheck('SYN_COOKIES', 'y', 'kspp', 'self_protection')) # another reason?
327 checklist.append(OptCheck('DEFAULT_MMAP_MIN_ADDR', '32768', 'kspp', 'self_protection'))
329 checklist.append(OptCheck('SECURITY_DMESG_RESTRICT', 'y', 'clipos', 'self_protection'))
330 checklist.append(OptCheck('DEBUG_VIRTUAL', 'y', 'clipos', 'self_protection'))
331 checklist.append(OptCheck('STATIC_USERMODEHELPER', 'y', 'clipos', 'self_protection')) # needs userspace support (systemd)
332 checklist.append(OptCheck('SLAB_MERGE_DEFAULT', 'is not set', 'clipos', 'self_protection')) # slab_nomerge
333 checklist.append(AND(OptCheck('GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set', 'clipos', 'self_protection'), \
335 checklist.append(OptCheck('RANDOM_TRUST_BOOTLOADER', 'is not set', 'clipos', 'self_protection'))
336 checklist.append(OptCheck('RANDOM_TRUST_CPU', 'is not set', 'clipos', 'self_protection'))
337 if arch == 'X86_64' or arch == 'X86_32':
338 checklist.append(AND(OptCheck('INTEL_IOMMU_SVM', 'y', 'clipos', 'self_protection'), \
339 iommu_support_is_set))
340 checklist.append(AND(OptCheck('INTEL_IOMMU_DEFAULT_ON', 'y', 'clipos', 'self_protection'), \
341 iommu_support_is_set))
343 checklist.append(AND(OptCheck('INTEL_IOMMU', 'y', 'clipos', 'self_protection'), \
344 iommu_support_is_set))
346 checklist.append(OptCheck('SLUB_DEBUG_ON', 'y', 'my', 'self_protection'))
347 checklist.append(OptCheck('RESET_ATTACK_MITIGATION', 'y', 'my', 'self_protection')) # needs userspace support (systemd)
349 checklist.append(AND(OptCheck('AMD_IOMMU_V2', 'y', 'my', 'self_protection'), \
350 iommu_support_is_set))
352 if arch == 'X86_64' or arch == 'ARM64' or arch == 'X86_32':
353 checklist.append(OptCheck('SECURITY', 'y', 'defconfig', 'security_policy')) # and choose your favourite LSM
355 checklist.append(OptCheck('SECURITY', 'y', 'kspp', 'security_policy')) # and choose your favourite LSM
356 checklist.append(OptCheck('SECURITY_YAMA', 'y', 'kspp', 'security_policy'))
357 checklist.append(OR(OptCheck('SECURITY_WRITABLE_HOOKS', 'is not set', 'my', 'security_policy'), \
358 OptCheck('SECURITY_SELINUX_DISABLE', 'is not set', 'kspp', 'security_policy')))
359 checklist.append(OptCheck('SECURITY_LOCKDOWN_LSM', 'y', 'clipos', 'security_policy'))
360 checklist.append(OptCheck('SECURITY_LOCKDOWN_LSM_EARLY', 'y', 'clipos', 'security_policy'))
361 checklist.append(OptCheck('LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y', 'clipos', 'security_policy'))
362 loadpin_is_set = OptCheck('SECURITY_LOADPIN', 'y', 'my', 'security_policy') # needs userspace support
363 checklist.append(loadpin_is_set)
364 checklist.append(AND(OptCheck('SECURITY_LOADPIN_ENFORCE', 'y', 'my', 'security_policy'), \
366 checklist.append(OptCheck('SECURITY_SAFESETID', 'y', 'my', 'security_policy'))
368 checklist.append(OptCheck('SECCOMP', 'y', 'defconfig', 'cut_attack_surface'))
369 checklist.append(OptCheck('SECCOMP_FILTER', 'y', 'defconfig', 'cut_attack_surface'))
370 if arch == 'X86_64' or arch == 'ARM64' or arch == 'X86_32':
371 checklist.append(OR(OptCheck('STRICT_DEVMEM', 'y', 'defconfig', 'cut_attack_surface'), \
372 devmem_not_set)) # refers to LOCKDOWN
374 checklist.append(modules_not_set)
375 checklist.append(devmem_not_set)
376 checklist.append(OR(OptCheck('IO_STRICT_DEVMEM', 'y', 'kspp', 'cut_attack_surface'), \
377 devmem_not_set)) # refers to LOCKDOWN
379 checklist.append(OR(OptCheck('STRICT_DEVMEM', 'y', 'kspp', 'cut_attack_surface'), \
380 devmem_not_set)) # refers to LOCKDOWN
382 checklist.append(OptCheck('LEGACY_VSYSCALL_NONE', 'y', 'kspp', 'cut_attack_surface')) # 'vsyscall=none'
383 checklist.append(OptCheck('ACPI_CUSTOM_METHOD', 'is not set', 'kspp', 'cut_attack_surface')) # refers to LOCKDOWN
384 checklist.append(OptCheck('COMPAT_BRK', 'is not set', 'kspp', 'cut_attack_surface'))
385 checklist.append(OptCheck('DEVKMEM', 'is not set', 'kspp', 'cut_attack_surface')) # refers to LOCKDOWN
386 checklist.append(OptCheck('COMPAT_VDSO', 'is not set', 'kspp', 'cut_attack_surface'))
387 checklist.append(OptCheck('BINFMT_MISC', 'is not set', 'kspp', 'cut_attack_surface'))
388 checklist.append(OptCheck('INET_DIAG', 'is not set', 'kspp', 'cut_attack_surface'))
389 checklist.append(OptCheck('KEXEC', 'is not set', 'kspp', 'cut_attack_surface')) # refers to LOCKDOWN
390 checklist.append(OptCheck('PROC_KCORE', 'is not set', 'kspp', 'cut_attack_surface')) # refers to LOCKDOWN
391 checklist.append(OptCheck('LEGACY_PTYS', 'is not set', 'kspp', 'cut_attack_surface'))
392 checklist.append(OptCheck('HIBERNATION', 'is not set', 'kspp', 'cut_attack_surface')) # refers to LOCKDOWN
393 checklist.append(OptCheck('IA32_EMULATION', 'is not set', 'kspp', 'cut_attack_surface'))
394 checklist.append(OptCheck('X86_X32', 'is not set', 'kspp', 'cut_attack_surface'))
395 checklist.append(OptCheck('MODIFY_LDT_SYSCALL', 'is not set', 'kspp', 'cut_attack_surface'))
396 checklist.append(OptCheck('OABI_COMPAT', 'is not set', 'kspp', 'cut_attack_surface'))
398 checklist.append(OptCheck('X86_PTDUMP', 'is not set', 'grsecurity', 'cut_attack_surface'))
399 checklist.append(OptCheck('ZSMALLOC_STAT', 'is not set', 'grsecurity', 'cut_attack_surface'))
400 checklist.append(OptCheck('PAGE_OWNER', 'is not set', 'grsecurity', 'cut_attack_surface'))
401 checklist.append(OptCheck('DEBUG_KMEMLEAK', 'is not set', 'grsecurity', 'cut_attack_surface'))
402 checklist.append(OptCheck('BINFMT_AOUT', 'is not set', 'grsecurity', 'cut_attack_surface'))
403 checklist.append(OptCheck('KPROBES', 'is not set', 'grsecurity', 'cut_attack_surface')) # refers to LOCKDOWN
404 checklist.append(OptCheck('UPROBES', 'is not set', 'grsecurity', 'cut_attack_surface'))
405 checklist.append(OptCheck('GENERIC_TRACER', 'is not set', 'grsecurity', 'cut_attack_surface')) # refers to LOCKDOWN
406 checklist.append(OptCheck('PROC_VMCORE', 'is not set', 'grsecurity', 'cut_attack_surface'))
407 checklist.append(OptCheck('PROC_PAGE_MONITOR', 'is not set', 'grsecurity', 'cut_attack_surface'))
408 checklist.append(OptCheck('USELIB', 'is not set', 'grsecurity', 'cut_attack_surface'))
409 checklist.append(OptCheck('CHECKPOINT_RESTORE', 'is not set', 'grsecurity', 'cut_attack_surface'))
410 checklist.append(OptCheck('USERFAULTFD', 'is not set', 'grsecurity', 'cut_attack_surface'))
411 checklist.append(OptCheck('HWPOISON_INJECT', 'is not set', 'grsecurity', 'cut_attack_surface'))
412 checklist.append(OptCheck('MEM_SOFT_DIRTY', 'is not set', 'grsecurity', 'cut_attack_surface'))
413 checklist.append(OptCheck('DEVPORT', 'is not set', 'grsecurity', 'cut_attack_surface')) # refers to LOCKDOWN
414 checklist.append(OptCheck('DEBUG_FS', 'is not set', 'grsecurity', 'cut_attack_surface')) # refers to LOCKDOWN
415 checklist.append(OptCheck('NOTIFIER_ERROR_INJECTION','is not set', 'grsecurity', 'cut_attack_surface'))
417 checklist.append(OptCheck('ACPI_TABLE_UPGRADE', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCKDOWN
418 checklist.append(OptCheck('X86_IOPL_IOPERM', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCKDOWN
419 checklist.append(OptCheck('EFI_TEST', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCKDOWN
420 checklist.append(OptCheck('BPF_SYSCALL', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCKDOWN
421 checklist.append(OptCheck('MMIOTRACE_TEST', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCKDOWN
423 if arch == 'X86_64' or arch == 'X86_32':
424 checklist.append(OptCheck('X86_INTEL_TSX_MODE_OFF', 'y', 'clipos', 'cut_attack_surface')) # tsx=off
425 checklist.append(OptCheck('STAGING', 'is not set', 'clipos', 'cut_attack_surface'))
426 checklist.append(OptCheck('KSM', 'is not set', 'clipos', 'cut_attack_surface')) # to prevent FLUSH+RELOAD attack
427 # checklist.append(OptCheck('IKCONFIG', 'is not set', 'clipos', 'cut_attack_surface')) # no, this info is needed for this check :)
428 checklist.append(OptCheck('KALLSYMS', 'is not set', 'clipos', 'cut_attack_surface'))
429 checklist.append(OptCheck('X86_VSYSCALL_EMULATION', 'is not set', 'clipos', 'cut_attack_surface'))
430 checklist.append(OptCheck('MAGIC_SYSRQ', 'is not set', 'clipos', 'cut_attack_surface'))
431 checklist.append(OptCheck('KEXEC_FILE', 'is not set', 'clipos', 'cut_attack_surface')) # refers to LOCKDOWN (permissive)
432 checklist.append(OptCheck('USER_NS', 'is not set', 'clipos', 'cut_attack_surface')) # user.max_user_namespaces=0
433 checklist.append(OptCheck('X86_MSR', 'is not set', 'clipos', 'cut_attack_surface')) # refers to LOCKDOWN
434 checklist.append(OptCheck('X86_CPUID', 'is not set', 'clipos', 'cut_attack_surface'))
435 checklist.append(AND(OptCheck('LDISC_AUTOLOAD', 'is not set', 'clipos', 'cut_attack_surface'), \
436 VerCheck((5, 1)))) # LDISC_AUTOLOAD can be disabled since v5.1
438 checklist.append(OptCheck('AIO', 'is not set', 'grapheneos', 'cut_attack_surface'))
440 checklist.append(OptCheck('MMIOTRACE', 'is not set', 'my', 'cut_attack_surface')) # refers to LOCKDOWN (permissive)
441 checklist.append(OptCheck('LIVEPATCH', 'is not set', 'my', 'cut_attack_surface'))
442 checklist.append(OptCheck('IP_DCCP', 'is not set', 'my', 'cut_attack_surface'))
443 checklist.append(OptCheck('IP_SCTP', 'is not set', 'my', 'cut_attack_surface'))
444 checklist.append(OptCheck('FTRACE', 'is not set', 'my', 'cut_attack_surface')) # refers to LOCKDOWN
445 checklist.append(OptCheck('BPF_JIT', 'is not set', 'my', 'cut_attack_surface'))
446 checklist.append(OptCheck('VIDEO_VIVID', 'is not set', 'my', 'cut_attack_surface'))
448 checklist.append(OptCheck('INTEGRITY', 'y', 'defconfig', 'userspace_hardening'))
450 checklist.append(OptCheck('ARM64_PTR_AUTH', 'y', 'defconfig', 'userspace_hardening'))
451 if arch == 'ARM' or arch == 'X86_32':
452 checklist.append(OptCheck('VMSPLIT_3G', 'y', 'defconfig', 'userspace_hardening'))
453 if arch == 'X86_64' or arch == 'ARM64':
454 checklist.append(OptCheck('ARCH_MMAP_RND_BITS', '32', 'clipos', 'userspace_hardening'))
455 if arch == 'X86_32' or arch == 'ARM':
456 checklist.append(OptCheck('ARCH_MMAP_RND_BITS', '16', 'my', 'userspace_hardening'))
458 # checklist.append(OptCheck('LKDTM', 'm', 'my', 'feature_test'))
461 def print_opt(opt, with_results):
462 print('CONFIG_{:<38}|{:^13}|{:^10}|{:^20}'.format(opt.name, opt.expected, opt.decision, opt.reason), end='')
464 print('| {}'.format(opt.result), end='')
468 def print_checklist(checklist, with_results):
472 opt = ['CONFIG_'+o.name, o.expected, o.decision, o.reason]
476 print(json.dumps(opts))
483 print('=' * sep_line_len)
484 print('{:^45}|{:^13}|{:^10}|{:^20}'.format('option name', 'desired val', 'decision', 'reason'), end='')
486 print('| {}'.format('check result'), end='')
488 print('=' * sep_line_len)
491 for opt in checklist:
492 if debug_mode and hasattr(opt, 'opts'):
493 print(' {:87}'.format('<<< ' + opt.__class__.__name__ + ' >>>'), end='')
495 print('| {}'.format(opt.result), end='')
498 if hasattr(o, 'ver_expected'):
499 ver_req = 'kernel version >= ' + str(o.ver_expected[0]) + '.' + str(o.ver_expected[1])
500 print('{:<91}'.format(ver_req), end='')
502 print('| {}'.format(o.result), end='')
505 print_opt(o, with_results)
507 print_opt(opt, with_results)
509 print('-' * sep_line_len)
513 def perform_checks(checklist, parsed_options):
514 for opt in checklist:
515 if hasattr(opt, 'opts'):
516 # prepare ComplexOptCheck
518 if hasattr(o, 'name'):
519 o.state = parsed_options.get(o.name, None)
521 # prepare simple OptCheck
522 if not hasattr(opt, 'name'):
523 sys.exit('[!] ERROR: bad OptCheck {}'.format(vars(opt)))
524 opt.state = parsed_options.get(opt.name, None)
528 def check_config_file(checklist, fname, arch):
529 with open(fname, 'r') as f:
530 parsed_options = OrderedDict()
531 opt_is_on = re.compile("CONFIG_[a-zA-Z0-9_]*=[a-zA-Z0-9_\"]*")
532 opt_is_off = re.compile("# CONFIG_[a-zA-Z0-9_]* is not set")
535 print('[+] Checking "{}" against {} hardening preferences...'.format(fname, arch))
536 for line in f.readlines():
541 if opt_is_on.match(line):
542 option, value = line[7:].split('=', 1)
543 elif opt_is_off.match(line):
544 option, value = line[9:].split(' ', 1)
545 if value != 'is not set':
546 sys.exit('[!] ERROR: bad disabled config option "{}"'.format(line))
548 if option in parsed_options:
549 sys.exit('[!] ERROR: config option "{}" exists multiple times'.format(line))
551 if option is not None:
552 parsed_options[option] = value
554 perform_checks(checklist, parsed_options)
558 for opt in checklist:
559 if hasattr(opt, 'opts'):
561 if hasattr(o, 'name'):
562 known_options.append(o.name)
564 known_options.append(opt.name)
565 for option, value in parsed_options.items():
566 if option not in known_options:
567 print('DEBUG: dunno about option {} ({})'.format(option, value))
569 print_checklist(checklist, True)
574 global kernel_version
576 config_checklist = []
578 parser = ArgumentParser(description='Checks the hardening options in the Linux kernel config')
579 parser.add_argument('-p', '--print', choices=supported_archs,
580 help='print hardening preferences for selected architecture')
581 parser.add_argument('-c', '--config',
582 help='check the config_file against these preferences')
583 parser.add_argument('--debug', action='store_true',
584 help='enable verbose debug mode')
585 parser.add_argument('--json', action='store_true',
586 help='print results in JSON format')
587 args = parser.parse_args()
591 print('[!] WARNING: debug mode is enabled')
594 if debug_mode and json_mode:
595 sys.exit('[!] ERROR: options --debug and --json cannot be used simultaneously')
598 arch, msg = detect_arch(args.config)
600 sys.exit('[!] ERROR: {}'.format(msg))
602 print('[+] Detected architecture: {}'.format(arch))
604 kernel_version, msg = detect_version(args.config)
605 if not kernel_version:
606 sys.exit('[!] ERROR: {}'.format(msg))
608 print('[+] Detected kernel version: {}.{}'.format(kernel_version[0], kernel_version[1]))
610 construct_checklist(config_checklist, arch)
611 check_config_file(config_checklist, args.config, arch)
612 error_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), config_checklist)))
613 ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), config_checklist)))
617 print('[+] config check is finished: \'OK\' - {} / \'FAIL\' - {}'.format(ok_count, error_count))
622 construct_checklist(config_checklist, arch)
624 print('[+] Printing kernel hardening preferences for {}...'.format(arch))
625 print_checklist(config_checklist, False)
630 if __name__ == '__main__':