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 # kernel.kptr_restrict=1
17 # lockdown=1 (is it changed?)
18 # page_alloc.shuffle=1
19 # iommu=force (does it help against DMA attacks?)
20 # page_poison=1 (if enabled)
24 # Mitigations of CPU vulnerabilities:
26 # mitigations=auto,nosmt
30 # spec_store_bypass_disable=on
37 # N.B. Hardening sysctls:
38 # net.core.bpf_jit_harden=2
40 # vm.unprivileged_userfaultfd=0
41 # kernel.perf_event_paranoid=3
42 # kernel.yama.ptrace_scope=1 (or even 3?)
43 # kernel.unprivileged_bpf_disabled=1
45 # fs.protected_symlinks = 1
46 # fs.protected_hardlinks = 1
47 # fs.protected_fifos = 2
48 # fs.protected_regular = 2
51 from argparse import ArgumentParser
52 from collections import OrderedDict
56 debug_mode = False # set it to True to print the unknown options from the config
57 json_mode = False # if True, print results in JSON format
59 supported_archs = [ 'X86_64', 'X86_32', 'ARM64', 'ARM' ]
65 def __init__(self, name, expected, decision, reason):
67 self.expected = expected
68 self.decision = decision
74 if self.expected == self.state:
76 elif self.state is None:
77 if self.expected == 'is not set':
78 self.result = 'OK: not found'
80 self.result = 'FAIL: not found'
82 self.result = 'FAIL: "' + self.state + '"'
84 if self.result.startswith('OK'):
85 return True, self.result
87 return False, self.result
90 return '{} = {}'.format(self.name, self.state)
94 def __init__(self, ver_expected):
95 self.ver_expected = ver_expected
99 if kernel_version[0] > self.ver_expected[0]:
100 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
101 return True, self.result
102 if kernel_version[0] < self.ver_expected[0]:
103 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
104 return False, self.result
105 if kernel_version[1] >= self.ver_expected[1]:
106 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
107 return True, self.result
109 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
110 return False, self.result
113 class ComplexOptCheck:
114 def __init__(self, *opts):
120 return self.opts[0].name
124 return self.opts[0].expected
128 return self.opts[0].state
132 return self.opts[0].decision
136 return self.opts[0].reason
139 class OR(ComplexOptCheck):
140 # self.opts[0] is the option which this OR-check is about.
142 # OR(<X_is_hardened>, <X_is_disabled>)
143 # OR(<X_is_hardened>, <X_is_hardened_old>)
147 sys.exit('[!] ERROR: invalid OR check')
149 for i, opt in enumerate(self.opts):
150 ret, msg = opt.check()
152 if i == 0 or not hasattr(opt, 'name'):
153 self.result = opt.result
155 self.result = 'OK: CONFIG_{} "{}"'.format(opt.name, opt.expected)
156 return True, self.result
157 self.result = self.opts[0].result
158 return False, self.result
161 class AND(ComplexOptCheck):
162 # self.opts[0] is the option which this AND-check is about.
163 # Use case: AND(<suboption>, <main_option>)
164 # Suboption is not checked if checking of the main_option is failed.
167 for i, opt in reversed(list(enumerate(self.opts))):
168 ret, msg = opt.check()
170 self.result = opt.result
171 return ret, self.result
173 if hasattr(opt, 'name'):
174 self.result = 'FAIL: CONFIG_{} is needed'.format(opt.name)
176 self.result = opt.result
177 return False, self.result
179 sys.exit('[!] ERROR: invalid AND check')
182 def detect_arch(fname):
183 with open(fname, 'r') as f:
184 arch_pattern = re.compile("CONFIG_[a-zA-Z0-9_]*=y")
187 print('[+] Trying to detect architecture in "{}"...'.format(fname))
188 for line in f.readlines():
189 if arch_pattern.match(line):
190 option, value = line[7:].split('=', 1)
191 if option in supported_archs:
195 return None, 'more than one supported architecture is detected'
197 return None, 'failed to detect architecture'
202 def detect_version(fname):
203 with open(fname, 'r') as f:
204 ver_pattern = re.compile("# Linux/.* Kernel Configuration")
206 print('[+] Trying to detect kernel version in "{}"...'.format(fname))
207 for line in f.readlines():
208 if ver_pattern.match(line):
211 print('[+] Found version line: "{}"'.format(line))
214 ver_numbers = ver_str.split('.')
215 if len(ver_numbers) < 3 or not ver_numbers[0].isdigit() or not ver_numbers[1].isdigit():
216 msg = 'failed to parse the version "' + ver_str + '"'
219 return (int(ver_numbers[0]), int(ver_numbers[1])), None
220 return None, 'no kernel version detected'
223 def construct_checklist(checklist, arch):
224 modules_not_set = OptCheck('MODULES', 'is not set', 'kspp', 'cut_attack_surface')
225 devmem_not_set = OptCheck('DEVMEM', 'is not set', 'kspp', 'cut_attack_surface') # refers to LOCK_DOWN_KERNEL
227 checklist.append(OptCheck('BUG', 'y', 'defconfig', 'self_protection'))
228 checklist.append(OR(OptCheck('STRICT_KERNEL_RWX', 'y', 'defconfig', 'self_protection'), \
229 OptCheck('DEBUG_RODATA', 'y', 'defconfig', 'self_protection'))) # before v4.11
230 checklist.append(OR(OptCheck('STACKPROTECTOR_STRONG', 'y', 'defconfig', 'self_protection'), \
231 OptCheck('CC_STACKPROTECTOR_STRONG', 'y', 'defconfig', 'self_protection')))
232 checklist.append(OptCheck('SLUB_DEBUG', 'y', 'defconfig', 'self_protection'))
233 checklist.append(OR(OptCheck('STRICT_MODULE_RWX', 'y', 'defconfig', 'self_protection'), \
234 OptCheck('DEBUG_SET_MODULE_RONX', 'y', 'defconfig', 'self_protection'), \
235 modules_not_set)) # DEBUG_SET_MODULE_RONX was before v4.11
236 checklist.append(OptCheck('GCC_PLUGINS', 'y', 'defconfig', 'self_protection'))
237 checklist.append(OR(OptCheck('REFCOUNT_FULL', 'y', 'defconfig', 'self_protection'), \
238 VerCheck((5, 5)))) # REFCOUNT_FULL is enabled by default since v5.5
239 if debug_mode or arch == 'X86_64' or arch == 'X86_32':
240 checklist.append(OptCheck('MICROCODE', 'y', 'defconfig', 'self_protection')) # is needed for mitigating CPU bugs
241 checklist.append(OptCheck('RETPOLINE', 'y', 'defconfig', 'self_protection'))
242 checklist.append(OptCheck('X86_SMAP', 'y', 'defconfig', 'self_protection'))
243 checklist.append(OR(OptCheck('X86_UMIP', 'y', 'defconfig', 'self_protection'), \
244 OptCheck('X86_INTEL_UMIP', 'y', 'defconfig', 'self_protection')))
245 iommu_support_is_set = OptCheck('IOMMU_SUPPORT', 'y', 'defconfig', 'self_protection') # is needed for mitigating DMA attacks
246 checklist.append(iommu_support_is_set)
247 checklist.append(OptCheck('SYN_COOKIES', 'y', 'defconfig', 'self_protection')) # another reason?
248 if debug_mode or arch == 'X86_64':
249 checklist.append(OptCheck('PAGE_TABLE_ISOLATION', 'y', 'defconfig', 'self_protection'))
250 checklist.append(OptCheck('RANDOMIZE_MEMORY', 'y', 'defconfig', 'self_protection'))
251 checklist.append(AND(OptCheck('INTEL_IOMMU', 'y', 'defconfig', 'self_protection'), \
252 iommu_support_is_set))
253 checklist.append(AND(OptCheck('AMD_IOMMU', 'y', 'defconfig', 'self_protection'), \
254 iommu_support_is_set))
255 if debug_mode or arch == 'ARM64':
256 checklist.append(OptCheck('UNMAP_KERNEL_AT_EL0', 'y', 'defconfig', 'self_protection'))
257 checklist.append(OptCheck('HARDEN_EL2_VECTORS', 'y', 'defconfig', 'self_protection'))
258 checklist.append(OptCheck('RODATA_FULL_DEFAULT_ENABLED', 'y', 'defconfig', 'self_protection'))
259 if debug_mode or arch == 'X86_64' or arch == 'ARM64':
260 checklist.append(OptCheck('VMAP_STACK', 'y', 'defconfig', 'self_protection'))
261 if debug_mode or arch == 'X86_64' or arch == 'ARM64' or arch == 'X86_32':
262 checklist.append(OptCheck('RANDOMIZE_BASE', 'y', 'defconfig', 'self_protection'))
263 checklist.append(OptCheck('THREAD_INFO_IN_TASK', 'y', 'defconfig', 'self_protection'))
264 if debug_mode or arch == 'ARM':
265 checklist.append(OptCheck('VMSPLIT_3G', 'y', 'defconfig', 'self_protection'))
266 checklist.append(OptCheck('CPU_SW_DOMAIN_PAN', 'y', 'defconfig', 'self_protection'))
267 checklist.append(OptCheck('STACKPROTECTOR_PER_TASK', 'y', 'defconfig', 'self_protection'))
268 if debug_mode or arch == 'ARM64' or arch == 'ARM':
269 checklist.append(OptCheck('HARDEN_BRANCH_PREDICTOR', 'y', 'defconfig', 'self_protection'))
271 checklist.append(OptCheck('BUG_ON_DATA_CORRUPTION', 'y', 'kspp', 'self_protection'))
272 checklist.append(OptCheck('DEBUG_WX', 'y', 'kspp', 'self_protection'))
273 checklist.append(OptCheck('SCHED_STACK_END_CHECK', 'y', 'kspp', 'self_protection'))
274 checklist.append(OptCheck('SLAB_FREELIST_HARDENED', 'y', 'kspp', 'self_protection'))
275 checklist.append(OptCheck('SLAB_FREELIST_RANDOM', 'y', 'kspp', 'self_protection'))
276 checklist.append(OptCheck('SHUFFLE_PAGE_ALLOCATOR', 'y', 'kspp', 'self_protection'))
277 checklist.append(OptCheck('FORTIFY_SOURCE', 'y', 'kspp', 'self_protection'))
278 randstruct_is_set = OptCheck('GCC_PLUGIN_RANDSTRUCT', 'y', 'kspp', 'self_protection')
279 checklist.append(randstruct_is_set)
280 checklist.append(OptCheck('GCC_PLUGIN_LATENT_ENTROPY', 'y', 'kspp', 'self_protection'))
281 checklist.append(OptCheck('DEBUG_LIST', 'y', 'kspp', 'self_protection'))
282 checklist.append(OptCheck('DEBUG_SG', 'y', 'kspp', 'self_protection'))
283 checklist.append(OptCheck('DEBUG_CREDENTIALS', 'y', 'kspp', 'self_protection'))
284 checklist.append(OptCheck('DEBUG_NOTIFIERS', 'y', 'kspp', 'self_protection'))
285 hardened_usercopy_is_set = OptCheck('HARDENED_USERCOPY', 'y', 'kspp', 'self_protection')
286 checklist.append(hardened_usercopy_is_set)
287 checklist.append(AND(OptCheck('HARDENED_USERCOPY_FALLBACK', 'is not set', 'kspp', 'self_protection'), \
288 hardened_usercopy_is_set))
289 checklist.append(OR(OptCheck('MODULE_SIG', 'y', 'kspp', 'self_protection'), \
291 checklist.append(OR(OptCheck('MODULE_SIG_ALL', 'y', 'kspp', 'self_protection'), \
293 checklist.append(OR(OptCheck('MODULE_SIG_SHA512', 'y', 'kspp', 'self_protection'), \
295 checklist.append(OR(OptCheck('MODULE_SIG_FORCE', 'y', 'kspp', 'self_protection'), \
296 modules_not_set)) # refers to LOCK_DOWN_KERNEL
297 checklist.append(OR(OptCheck('INIT_STACK_ALL', 'y', 'kspp', 'self_protection'), \
298 OptCheck('GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y', 'kspp', 'self_protection')))
299 checklist.append(OptCheck('INIT_ON_ALLOC_DEFAULT_ON', 'y', 'kspp', 'self_protection'))
300 checklist.append(OR(OptCheck('INIT_ON_FREE_DEFAULT_ON', 'y', 'kspp', 'self_protection'), \
301 OptCheck('PAGE_POISONING', 'y', 'kspp', 'self_protection'))) # before v5.3
302 if debug_mode or arch == 'X86_64' or arch == 'ARM64' or arch == 'X86_32':
303 stackleak_is_set = OptCheck('GCC_PLUGIN_STACKLEAK', 'y', 'kspp', 'self_protection')
304 checklist.append(stackleak_is_set)
305 checklist.append(AND(OptCheck('STACKLEAK_METRICS', 'is not set', 'clipos', 'self_protection'), \
307 checklist.append(AND(OptCheck('STACKLEAK_RUNTIME_DISABLE', 'is not set', 'clipos', 'self_protection'), \
309 if debug_mode or arch == 'X86_64' or arch == 'X86_32':
310 checklist.append(OptCheck('DEFAULT_MMAP_MIN_ADDR', '65536', 'kspp', 'self_protection'))
311 if debug_mode or arch == 'X86_32':
312 checklist.append(OptCheck('HIGHMEM64G', 'y', 'kspp', 'self_protection'))
313 checklist.append(OptCheck('X86_PAE', 'y', 'kspp', 'self_protection'))
314 if debug_mode or arch == 'ARM64':
315 checklist.append(OptCheck('ARM64_SW_TTBR0_PAN', 'y', 'kspp', 'self_protection'))
316 if debug_mode or arch == 'ARM64' or arch == 'ARM':
317 checklist.append(OptCheck('SYN_COOKIES', 'y', 'kspp', 'self_protection')) # another reason?
318 checklist.append(OptCheck('DEFAULT_MMAP_MIN_ADDR', '32768', 'kspp', 'self_protection'))
320 checklist.append(OptCheck('SECURITY_DMESG_RESTRICT', 'y', 'clipos', 'self_protection'))
321 checklist.append(OptCheck('DEBUG_VIRTUAL', 'y', 'clipos', 'self_protection'))
322 checklist.append(OptCheck('STATIC_USERMODEHELPER', 'y', 'clipos', 'self_protection')) # needs userspace support (systemd)
323 checklist.append(OptCheck('SLAB_MERGE_DEFAULT', 'is not set', 'clipos', 'self_protection')) # slab_nomerge
324 checklist.append(AND(OptCheck('GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set', 'clipos', 'self_protection'), \
326 if debug_mode or arch == 'X86_64' or arch == 'X86_32':
327 checklist.append(OptCheck('RANDOM_TRUST_CPU', 'is not set', 'clipos', 'self_protection'))
328 checklist.append(AND(OptCheck('INTEL_IOMMU_SVM', 'y', 'clipos', 'self_protection'), \
329 iommu_support_is_set))
330 checklist.append(AND(OptCheck('INTEL_IOMMU_DEFAULT_ON', 'y', 'clipos', 'self_protection'), \
331 iommu_support_is_set))
333 checklist.append(OptCheck('SLUB_DEBUG_ON', 'y', 'my', 'self_protection'))
334 checklist.append(OptCheck('RESET_ATTACK_MITIGATION', 'y', 'my', 'self_protection')) # needs userspace support (systemd)
335 if debug_mode or arch == 'X86_64':
336 checklist.append(AND(OptCheck('AMD_IOMMU_V2', 'y', 'my', 'self_protection'), \
337 iommu_support_is_set))
338 if debug_mode or arch == 'X86_32':
339 checklist.append(OptCheck('PAGE_TABLE_ISOLATION', 'y', 'my', 'self_protection'))
341 if debug_mode or arch == 'X86_64' or arch == 'ARM64' or arch == 'X86_32':
342 checklist.append(OptCheck('SECURITY', 'y', 'defconfig', 'security_policy')) # and choose your favourite LSM
343 if debug_mode or arch == 'ARM':
344 checklist.append(OptCheck('SECURITY', 'y', 'kspp', 'security_policy')) # and choose your favourite LSM
345 checklist.append(OptCheck('SECURITY_YAMA', 'y', 'kspp', 'security_policy'))
346 checklist.append(OptCheck('SECURITY_LOADPIN', 'y', 'my', 'security_policy')) # needs userspace support
347 checklist.append(OptCheck('SECURITY_LOCKDOWN_LSM', 'y', 'my', 'security_policy'))
348 checklist.append(OptCheck('SECURITY_LOCKDOWN_LSM_EARLY', 'y', 'my', 'security_policy'))
349 checklist.append(OptCheck('LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y', 'my', 'security_policy'))
350 checklist.append(OptCheck('SECURITY_SAFESETID', 'y', 'my', 'security_policy'))
351 checklist.append(OptCheck('SECURITY_WRITABLE_HOOKS', 'is not set', 'my', 'security_policy'))
353 checklist.append(OptCheck('SECCOMP', 'y', 'defconfig', 'cut_attack_surface'))
354 checklist.append(OptCheck('SECCOMP_FILTER', 'y', 'defconfig', 'cut_attack_surface'))
355 if debug_mode or arch == 'X86_64' or arch == 'ARM64' or arch == 'X86_32':
356 checklist.append(OR(OptCheck('STRICT_DEVMEM', 'y', 'defconfig', 'cut_attack_surface'), \
357 devmem_not_set)) # refers to LOCK_DOWN_KERNEL
359 checklist.append(modules_not_set)
360 checklist.append(devmem_not_set)
361 checklist.append(OR(OptCheck('IO_STRICT_DEVMEM', 'y', 'kspp', 'cut_attack_surface'), \
362 devmem_not_set)) # refers to LOCK_DOWN_KERNEL
363 if debug_mode or arch == 'ARM':
364 checklist.append(OR(OptCheck('STRICT_DEVMEM', 'y', 'kspp', 'cut_attack_surface'), \
365 devmem_not_set)) # refers to LOCK_DOWN_KERNEL
366 checklist.append(OptCheck('ACPI_CUSTOM_METHOD', 'is not set', 'kspp', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
367 checklist.append(OptCheck('COMPAT_BRK', 'is not set', 'kspp', 'cut_attack_surface'))
368 checklist.append(OptCheck('DEVKMEM', 'is not set', 'kspp', 'cut_attack_surface'))
369 checklist.append(OptCheck('COMPAT_VDSO', 'is not set', 'kspp', 'cut_attack_surface'))
370 checklist.append(OptCheck('BINFMT_MISC', 'is not set', 'kspp', 'cut_attack_surface'))
371 checklist.append(OptCheck('INET_DIAG', 'is not set', 'kspp', 'cut_attack_surface'))
372 checklist.append(OptCheck('KEXEC', 'is not set', 'kspp', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
373 checklist.append(OptCheck('PROC_KCORE', 'is not set', 'kspp', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
374 checklist.append(OptCheck('LEGACY_PTYS', 'is not set', 'kspp', 'cut_attack_surface'))
375 checklist.append(OptCheck('HIBERNATION', 'is not set', 'kspp', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
376 if debug_mode or arch == 'X86_64':
377 checklist.append(OptCheck('LEGACY_VSYSCALL_NONE', 'y', 'kspp', 'cut_attack_surface')) # 'vsyscall=none'
378 checklist.append(OptCheck('IA32_EMULATION', 'is not set', 'kspp', 'cut_attack_surface'))
379 checklist.append(OptCheck('X86_X32', 'is not set', 'kspp', 'cut_attack_surface'))
380 checklist.append(OptCheck('MODIFY_LDT_SYSCALL', 'is not set', 'kspp', 'cut_attack_surface'))
381 if debug_mode or arch == 'ARM':
382 checklist.append(OptCheck('OABI_COMPAT', 'is not set', 'kspp', 'cut_attack_surface'))
384 checklist.append(OptCheck('X86_PTDUMP', 'is not set', 'grsecurity', 'cut_attack_surface'))
385 checklist.append(OptCheck('ZSMALLOC_STAT', 'is not set', 'grsecurity', 'cut_attack_surface'))
386 checklist.append(OptCheck('PAGE_OWNER', 'is not set', 'grsecurity', 'cut_attack_surface'))
387 checklist.append(OptCheck('DEBUG_KMEMLEAK', 'is not set', 'grsecurity', 'cut_attack_surface'))
388 checklist.append(OptCheck('BINFMT_AOUT', 'is not set', 'grsecurity', 'cut_attack_surface'))
389 checklist.append(OptCheck('KPROBES', 'is not set', 'grsecurity', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
390 checklist.append(OptCheck('UPROBES', 'is not set', 'grsecurity', 'cut_attack_surface'))
391 checklist.append(OptCheck('GENERIC_TRACER', 'is not set', 'grsecurity', 'cut_attack_surface'))
392 checklist.append(OptCheck('PROC_VMCORE', 'is not set', 'grsecurity', 'cut_attack_surface'))
393 checklist.append(OptCheck('PROC_PAGE_MONITOR', 'is not set', 'grsecurity', 'cut_attack_surface'))
394 checklist.append(OptCheck('USELIB', 'is not set', 'grsecurity', 'cut_attack_surface'))
395 checklist.append(OptCheck('CHECKPOINT_RESTORE', 'is not set', 'grsecurity', 'cut_attack_surface'))
396 checklist.append(OptCheck('USERFAULTFD', 'is not set', 'grsecurity', 'cut_attack_surface'))
397 checklist.append(OptCheck('HWPOISON_INJECT', 'is not set', 'grsecurity', 'cut_attack_surface'))
398 checklist.append(OptCheck('MEM_SOFT_DIRTY', 'is not set', 'grsecurity', 'cut_attack_surface'))
399 checklist.append(OptCheck('DEVPORT', 'is not set', 'grsecurity', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
400 checklist.append(OptCheck('DEBUG_FS', 'is not set', 'grsecurity', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
401 checklist.append(OptCheck('NOTIFIER_ERROR_INJECTION','is not set', 'grsecurity', 'cut_attack_surface'))
403 checklist.append(OptCheck('ACPI_TABLE_UPGRADE', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
404 checklist.append(OptCheck('ACPI_APEI_EINJ', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
405 checklist.append(OptCheck('PROFILING', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
406 checklist.append(OptCheck('BPF_SYSCALL', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
407 checklist.append(OptCheck('MMIOTRACE_TEST', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
409 checklist.append(OptCheck('KSM', 'is not set', 'clipos', 'cut_attack_surface')) # to prevent FLUSH+RELOAD attack
410 # checklist.append(OptCheck('IKCONFIG', 'is not set', 'clipos', 'cut_attack_surface')) # no, this info is needed for this check :)
411 checklist.append(OptCheck('KALLSYMS', 'is not set', 'clipos', 'cut_attack_surface'))
412 checklist.append(OptCheck('X86_VSYSCALL_EMULATION', 'is not set', 'clipos', 'cut_attack_surface'))
413 checklist.append(OptCheck('MAGIC_SYSRQ', 'is not set', 'clipos', 'cut_attack_surface'))
414 checklist.append(OptCheck('KEXEC_FILE', 'is not set', 'clipos', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL (permissive)
415 checklist.append(OptCheck('USER_NS', 'is not set', 'clipos', 'cut_attack_surface')) # user.max_user_namespaces=0
416 checklist.append(AND(OptCheck('LDISC_AUTOLOAD', 'is not set', 'clipos', 'cut_attack_surface'), \
417 VerCheck((5, 1)))) # LDISC_AUTOLOAD can be disabled since v5.1
419 checklist.append(OptCheck('MMIOTRACE', 'is not set', 'my', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL (permissive)
420 checklist.append(OptCheck('LIVEPATCH', 'is not set', 'my', 'cut_attack_surface'))
421 checklist.append(OptCheck('IP_DCCP', 'is not set', 'my', 'cut_attack_surface'))
422 checklist.append(OptCheck('IP_SCTP', 'is not set', 'my', 'cut_attack_surface'))
423 checklist.append(OptCheck('FTRACE', 'is not set', 'my', 'cut_attack_surface'))
424 checklist.append(OptCheck('BPF_JIT', 'is not set', 'my', 'cut_attack_surface'))
425 checklist.append(OptCheck('VIDEO_VIVID', 'is not set', 'my', 'cut_attack_surface'))
426 if debug_mode or arch == 'X86_32':
427 checklist.append(OptCheck('MODIFY_LDT_SYSCALL', 'is not set', 'my', 'cut_attack_surface'))
429 if debug_mode or arch == 'ARM64':
430 checklist.append(OptCheck('ARM64_PTR_AUTH', 'y', 'defconfig', 'userspace_hardening'))
431 if debug_mode or arch == 'X86_64' or arch == 'ARM64':
432 checklist.append(OptCheck('ARCH_MMAP_RND_BITS', '32', 'clipos', 'userspace_hardening'))
433 if debug_mode or arch == 'X86_32' or arch == 'ARM':
434 checklist.append(OptCheck('ARCH_MMAP_RND_BITS', '16', 'my', 'userspace_hardening'))
436 # checklist.append(OptCheck('LKDTM', 'm', 'my', 'feature_test'))
439 def print_checklist(checklist, with_results):
443 opt = ['CONFIG_'+o.name, o.expected, o.decision, o.reason]
447 print(json.dumps(opts))
451 print('{:^45}|{:^13}|{:^10}|{:^20}'.format('option name', 'desired val', 'decision', 'reason'), end='')
454 print('| {}'.format('check result'), end='')
458 print('=' * sep_line_len)
460 for opt in checklist:
461 print('CONFIG_{:<38}|{:^13}|{:^10}|{:^20}'.format(opt.name, opt.expected, opt.decision, opt.reason), end='')
463 print('| {}'.format(opt.result), end='')
468 def perform_checks(checklist, parsed_options):
469 for opt in checklist:
470 if hasattr(opt, 'opts'):
471 # prepare ComplexOptCheck
473 if hasattr(o, 'name'):
474 o.state = parsed_options.get(o.name, None)
476 # prepare simple OptCheck
477 if not hasattr(opt, 'name'):
478 sys.exit('[!] ERROR: bad OptCheck {}'.format(vars(opt)))
479 opt.state = parsed_options.get(opt.name, None)
483 def check_config_file(checklist, fname):
484 with open(fname, 'r') as f:
485 parsed_options = OrderedDict()
486 opt_is_on = re.compile("CONFIG_[a-zA-Z0-9_]*=[a-zA-Z0-9_\"]*")
487 opt_is_off = re.compile("# CONFIG_[a-zA-Z0-9_]* is not set")
490 print('[+] Checking "{}" against hardening preferences...'.format(fname))
491 for line in f.readlines():
496 if opt_is_on.match(line):
497 option, value = line[7:].split('=', 1)
498 elif opt_is_off.match(line):
499 option, value = line[9:].split(' ', 1)
500 if value != 'is not set':
501 sys.exit('[!] ERROR: bad disabled config option "{}"'.format(line))
503 if option in parsed_options:
504 sys.exit('[!] ERROR: config option "{}" exists multiple times'.format(line))
506 if option is not None:
507 parsed_options[option] = value
509 perform_checks(checklist, parsed_options)
512 known_options = [opt.name for opt in checklist]
513 for option, value in parsed_options.items():
514 if option not in known_options:
515 print("DEBUG: dunno about option {} ({})".format(option, value))
517 print_checklist(checklist, True)
520 if __name__ == '__main__':
521 parser = ArgumentParser(description='Checks the hardening options in the Linux kernel config')
522 parser.add_argument('-p', '--print', choices=supported_archs,
523 help='print hardening preferences for selected architecture')
524 parser.add_argument('-c', '--config',
525 help='check the config_file against these preferences')
526 parser.add_argument('--debug', action='store_true',
527 help='enable internal debug mode')
528 parser.add_argument('--json', action='store_true',
529 help='print results in JSON format')
530 args = parser.parse_args()
536 if debug_mode and json_mode:
537 sys.exit('[!] ERROR: options --debug and --json cannot be used simultaneously')
540 arch, msg = detect_arch(args.config)
542 sys.exit('[!] ERROR: {}'.format(msg))
544 print('[+] Detected architecture: {}'.format(arch))
546 kernel_version, msg = detect_version(args.config)
547 if not kernel_version:
548 sys.exit('[!] ERROR: {}'.format(msg))
550 print('[+] Detected kernel version: {}.{}'.format(kernel_version[0], kernel_version[1]))
552 construct_checklist(config_checklist, arch)
553 check_config_file(config_checklist, args.config)
554 error_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), config_checklist)))
555 ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), config_checklist)))
559 print('[+] config check is finished: \'OK\' - {} / \'FAIL\' - {}'.format(ok_count, error_count))
564 construct_checklist(config_checklist, arch)
566 print('[+] Printing kernel hardening preferences for {}...'.format(arch))
567 print_checklist(config_checklist, False)