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
91 def __init__(self, ver_expected):
92 self.ver_expected = ver_expected
96 if kernel_version[0] > self.ver_expected[0]:
97 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
98 return True, self.result
99 if kernel_version[0] < self.ver_expected[0]:
100 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
101 return False, self.result
102 if kernel_version[1] >= self.ver_expected[1]:
103 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
104 return True, self.result
106 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
107 return False, self.result
110 class ComplexOptCheck:
111 def __init__(self, *opts):
117 return self.opts[0].name
121 return self.opts[0].expected
125 return self.opts[0].state
129 return self.opts[0].decision
133 return self.opts[0].reason
136 class OR(ComplexOptCheck):
137 # self.opts[0] is the option which this OR-check is about.
139 # OR(<X_is_hardened>, <X_is_disabled>)
140 # OR(<X_is_hardened>, <X_is_hardened_old>)
144 sys.exit('[!] ERROR: invalid OR check')
146 for i, opt in enumerate(self.opts):
147 ret, msg = opt.check()
149 if i == 0 or not hasattr(opt, 'name'):
150 self.result = opt.result
152 self.result = 'OK: CONFIG_{} "{}"'.format(opt.name, opt.expected)
153 return True, self.result
154 self.result = self.opts[0].result
155 return False, self.result
158 class AND(ComplexOptCheck):
159 # self.opts[0] is the option which this AND-check is about.
160 # Use case: AND(<suboption>, <main_option>)
161 # Suboption is not checked if checking of the main_option is failed.
164 for i, opt in reversed(list(enumerate(self.opts))):
165 ret, msg = opt.check()
167 self.result = opt.result
168 return ret, self.result
170 if hasattr(opt, 'name'):
171 self.result = 'FAIL: CONFIG_{} is needed'.format(opt.name)
173 self.result = opt.result
174 return False, self.result
176 sys.exit('[!] ERROR: invalid AND check')
179 def detect_arch(fname):
180 with open(fname, 'r') as f:
181 arch_pattern = re.compile("CONFIG_[a-zA-Z0-9_]*=y")
184 print('[+] Trying to detect architecture in "{}"...'.format(fname))
185 for line in f.readlines():
186 if arch_pattern.match(line):
187 option, value = line[7:].split('=', 1)
188 if option in supported_archs:
192 return None, 'more than one supported architecture is detected'
194 return None, 'failed to detect architecture'
199 def detect_version(fname):
200 with open(fname, 'r') as f:
201 ver_pattern = re.compile("# Linux/.* Kernel Configuration")
203 print('[+] Trying to detect kernel version in "{}"...'.format(fname))
204 for line in f.readlines():
205 if ver_pattern.match(line):
208 print('[+] Found version line: "{}"'.format(line))
211 ver_numbers = ver_str.split('.')
212 if len(ver_numbers) < 3 or not ver_numbers[0].isdigit() or not ver_numbers[1].isdigit():
213 msg = 'failed to parse the version "' + ver_str + '"'
216 return (int(ver_numbers[0]), int(ver_numbers[1])), None
217 return None, 'no kernel version detected'
220 def construct_checklist(checklist, arch):
221 modules_not_set = OptCheck('MODULES', 'is not set', 'kspp', 'cut_attack_surface')
222 devmem_not_set = OptCheck('DEVMEM', 'is not set', 'kspp', 'cut_attack_surface') # refers to LOCK_DOWN_KERNEL
224 checklist.append(OptCheck('BUG', 'y', 'defconfig', 'self_protection'))
225 checklist.append(OR(OptCheck('STRICT_KERNEL_RWX', 'y', 'defconfig', 'self_protection'), \
226 OptCheck('DEBUG_RODATA', 'y', 'defconfig', 'self_protection'))) # before v4.11
227 checklist.append(OR(OptCheck('STACKPROTECTOR_STRONG', 'y', 'defconfig', 'self_protection'), \
228 OptCheck('CC_STACKPROTECTOR_STRONG', 'y', 'defconfig', 'self_protection')))
229 checklist.append(OptCheck('SLUB_DEBUG', 'y', 'defconfig', 'self_protection'))
230 checklist.append(OR(OptCheck('STRICT_MODULE_RWX', 'y', 'defconfig', 'self_protection'), \
231 OptCheck('DEBUG_SET_MODULE_RONX', 'y', 'defconfig', 'self_protection'), \
232 modules_not_set)) # DEBUG_SET_MODULE_RONX was before v4.11
233 checklist.append(OptCheck('GCC_PLUGINS', 'y', 'defconfig', 'self_protection'))
234 checklist.append(OR(OptCheck('REFCOUNT_FULL', 'y', 'defconfig', 'self_protection'), \
235 VerCheck((5, 5)))) # REFCOUNT_FULL is enabled by default since v5.5
236 if debug_mode or arch == 'X86_64' or arch == 'X86_32':
237 checklist.append(OptCheck('MICROCODE', 'y', 'defconfig', 'self_protection')) # is needed for mitigating CPU bugs
238 checklist.append(OptCheck('RETPOLINE', 'y', 'defconfig', 'self_protection'))
239 checklist.append(OptCheck('X86_SMAP', 'y', 'defconfig', 'self_protection'))
240 checklist.append(OR(OptCheck('X86_UMIP', 'y', 'defconfig', 'self_protection'), \
241 OptCheck('X86_INTEL_UMIP', 'y', 'defconfig', 'self_protection')))
242 iommu_support_is_set = OptCheck('IOMMU_SUPPORT', 'y', 'defconfig', 'self_protection') # is needed for mitigating DMA attacks
243 checklist.append(iommu_support_is_set)
244 checklist.append(OptCheck('SYN_COOKIES', 'y', 'defconfig', 'self_protection')) # another reason?
245 if debug_mode or arch == 'X86_64':
246 checklist.append(OptCheck('PAGE_TABLE_ISOLATION', 'y', 'defconfig', 'self_protection'))
247 checklist.append(OptCheck('RANDOMIZE_MEMORY', 'y', 'defconfig', 'self_protection'))
248 checklist.append(AND(OptCheck('INTEL_IOMMU', 'y', 'defconfig', 'self_protection'), \
249 iommu_support_is_set))
250 checklist.append(AND(OptCheck('AMD_IOMMU', 'y', 'defconfig', 'self_protection'), \
251 iommu_support_is_set))
252 if debug_mode or arch == 'ARM64':
253 checklist.append(OptCheck('UNMAP_KERNEL_AT_EL0', 'y', 'defconfig', 'self_protection'))
254 checklist.append(OptCheck('HARDEN_EL2_VECTORS', 'y', 'defconfig', 'self_protection'))
255 checklist.append(OptCheck('RODATA_FULL_DEFAULT_ENABLED', 'y', 'defconfig', 'self_protection'))
256 if debug_mode or arch == 'X86_64' or arch == 'ARM64':
257 checklist.append(OptCheck('VMAP_STACK', 'y', 'defconfig', 'self_protection'))
258 if debug_mode or arch == 'X86_64' or arch == 'ARM64' or arch == 'X86_32':
259 checklist.append(OptCheck('RANDOMIZE_BASE', 'y', 'defconfig', 'self_protection'))
260 checklist.append(OptCheck('THREAD_INFO_IN_TASK', 'y', 'defconfig', 'self_protection'))
261 if debug_mode or arch == 'ARM':
262 checklist.append(OptCheck('VMSPLIT_3G', 'y', 'defconfig', 'self_protection'))
263 checklist.append(OptCheck('CPU_SW_DOMAIN_PAN', 'y', 'defconfig', 'self_protection'))
264 checklist.append(OptCheck('STACKPROTECTOR_PER_TASK', 'y', 'defconfig', 'self_protection'))
265 if debug_mode or arch == 'ARM64' or arch == 'ARM':
266 checklist.append(OptCheck('HARDEN_BRANCH_PREDICTOR', 'y', 'defconfig', 'self_protection'))
268 checklist.append(OptCheck('BUG_ON_DATA_CORRUPTION', 'y', 'kspp', 'self_protection'))
269 checklist.append(OptCheck('DEBUG_WX', 'y', 'kspp', 'self_protection'))
270 checklist.append(OptCheck('SCHED_STACK_END_CHECK', 'y', 'kspp', 'self_protection'))
271 checklist.append(OptCheck('SLAB_FREELIST_HARDENED', 'y', 'kspp', 'self_protection'))
272 checklist.append(OptCheck('SLAB_FREELIST_RANDOM', 'y', 'kspp', 'self_protection'))
273 checklist.append(OptCheck('SHUFFLE_PAGE_ALLOCATOR', 'y', 'kspp', 'self_protection'))
274 checklist.append(OptCheck('FORTIFY_SOURCE', 'y', 'kspp', 'self_protection'))
275 randstruct_is_set = OptCheck('GCC_PLUGIN_RANDSTRUCT', 'y', 'kspp', 'self_protection')
276 checklist.append(randstruct_is_set)
277 checklist.append(OptCheck('GCC_PLUGIN_LATENT_ENTROPY', 'y', 'kspp', 'self_protection'))
278 checklist.append(OptCheck('DEBUG_LIST', 'y', 'kspp', 'self_protection'))
279 checklist.append(OptCheck('DEBUG_SG', 'y', 'kspp', 'self_protection'))
280 checklist.append(OptCheck('DEBUG_CREDENTIALS', 'y', 'kspp', 'self_protection'))
281 checklist.append(OptCheck('DEBUG_NOTIFIERS', 'y', 'kspp', 'self_protection'))
282 hardened_usercopy_is_set = OptCheck('HARDENED_USERCOPY', 'y', 'kspp', 'self_protection')
283 checklist.append(hardened_usercopy_is_set)
284 checklist.append(AND(OptCheck('HARDENED_USERCOPY_FALLBACK', 'is not set', 'kspp', 'self_protection'), \
285 hardened_usercopy_is_set))
286 checklist.append(OR(OptCheck('MODULE_SIG', 'y', 'kspp', 'self_protection'), \
288 checklist.append(OR(OptCheck('MODULE_SIG_ALL', 'y', 'kspp', 'self_protection'), \
290 checklist.append(OR(OptCheck('MODULE_SIG_SHA512', 'y', 'kspp', 'self_protection'), \
292 checklist.append(OR(OptCheck('MODULE_SIG_FORCE', 'y', 'kspp', 'self_protection'), \
293 modules_not_set)) # refers to LOCK_DOWN_KERNEL
294 checklist.append(OR(OptCheck('INIT_STACK_ALL', 'y', 'kspp', 'self_protection'), \
295 OptCheck('GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y', 'kspp', 'self_protection')))
296 checklist.append(OptCheck('INIT_ON_ALLOC_DEFAULT_ON', 'y', 'kspp', 'self_protection'))
297 checklist.append(OR(OptCheck('INIT_ON_FREE_DEFAULT_ON', 'y', 'kspp', 'self_protection'), \
298 OptCheck('PAGE_POISONING', 'y', 'kspp', 'self_protection'))) # before v5.3
299 if debug_mode or arch == 'X86_64' or arch == 'ARM64' or arch == 'X86_32':
300 stackleak_is_set = OptCheck('GCC_PLUGIN_STACKLEAK', 'y', 'kspp', 'self_protection')
301 checklist.append(stackleak_is_set)
302 checklist.append(AND(OptCheck('STACKLEAK_METRICS', 'is not set', 'clipos', 'self_protection'), \
304 checklist.append(AND(OptCheck('STACKLEAK_RUNTIME_DISABLE', 'is not set', 'clipos', 'self_protection'), \
306 if debug_mode or arch == 'X86_64' or arch == 'X86_32':
307 checklist.append(OptCheck('DEFAULT_MMAP_MIN_ADDR', '65536', 'kspp', 'self_protection'))
308 if debug_mode or arch == 'X86_32':
309 checklist.append(OptCheck('HIGHMEM64G', 'y', 'kspp', 'self_protection'))
310 checklist.append(OptCheck('X86_PAE', 'y', 'kspp', 'self_protection'))
311 if debug_mode or arch == 'ARM64':
312 checklist.append(OptCheck('ARM64_SW_TTBR0_PAN', 'y', 'kspp', 'self_protection'))
313 if debug_mode or arch == 'ARM64' or arch == 'ARM':
314 checklist.append(OptCheck('SYN_COOKIES', 'y', 'kspp', 'self_protection')) # another reason?
315 checklist.append(OptCheck('DEFAULT_MMAP_MIN_ADDR', '32768', 'kspp', 'self_protection'))
317 checklist.append(OptCheck('SECURITY_DMESG_RESTRICT', 'y', 'clipos', 'self_protection'))
318 checklist.append(OptCheck('DEBUG_VIRTUAL', 'y', 'clipos', 'self_protection'))
319 checklist.append(OptCheck('STATIC_USERMODEHELPER', 'y', 'clipos', 'self_protection')) # needs userspace support (systemd)
320 checklist.append(OptCheck('SLAB_MERGE_DEFAULT', 'is not set', 'clipos', 'self_protection')) # slab_nomerge
321 checklist.append(AND(OptCheck('GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set', 'clipos', 'self_protection'), \
323 if debug_mode or arch == 'X86_64' or arch == 'X86_32':
324 checklist.append(OptCheck('RANDOM_TRUST_CPU', 'is not set', 'clipos', 'self_protection'))
325 checklist.append(AND(OptCheck('INTEL_IOMMU_SVM', 'y', 'clipos', 'self_protection'), \
326 iommu_support_is_set))
327 checklist.append(AND(OptCheck('INTEL_IOMMU_DEFAULT_ON', 'y', 'clipos', 'self_protection'), \
328 iommu_support_is_set))
330 checklist.append(OptCheck('SLUB_DEBUG_ON', 'y', 'my', 'self_protection'))
331 checklist.append(OptCheck('RESET_ATTACK_MITIGATION', 'y', 'my', 'self_protection')) # needs userspace support (systemd)
332 if debug_mode or arch == 'X86_64':
333 checklist.append(AND(OptCheck('AMD_IOMMU_V2', 'y', 'my', 'self_protection'), \
334 iommu_support_is_set))
335 if debug_mode or arch == 'X86_32':
336 checklist.append(OptCheck('PAGE_TABLE_ISOLATION', 'y', 'my', 'self_protection'))
338 if debug_mode or arch == 'X86_64' or arch == 'ARM64' or arch == 'X86_32':
339 checklist.append(OptCheck('SECURITY', 'y', 'defconfig', 'security_policy')) # and choose your favourite LSM
340 if debug_mode or arch == 'ARM':
341 checklist.append(OptCheck('SECURITY', 'y', 'kspp', 'security_policy')) # and choose your favourite LSM
342 checklist.append(OptCheck('SECURITY_YAMA', 'y', 'kspp', 'security_policy'))
343 checklist.append(OptCheck('SECURITY_LOADPIN', 'y', 'my', 'security_policy')) # needs userspace support
344 checklist.append(OptCheck('SECURITY_LOCKDOWN_LSM', 'y', 'my', 'security_policy'))
345 checklist.append(OptCheck('SECURITY_LOCKDOWN_LSM_EARLY', 'y', 'my', 'security_policy'))
346 checklist.append(OptCheck('LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y', 'my', 'security_policy'))
347 checklist.append(OptCheck('SECURITY_SAFESETID', 'y', 'my', 'security_policy'))
348 checklist.append(OptCheck('SECURITY_WRITABLE_HOOKS', 'is not set', 'my', 'security_policy'))
350 checklist.append(OptCheck('SECCOMP', 'y', 'defconfig', 'cut_attack_surface'))
351 checklist.append(OptCheck('SECCOMP_FILTER', 'y', 'defconfig', 'cut_attack_surface'))
352 if debug_mode or arch == 'X86_64' or arch == 'ARM64' or arch == 'X86_32':
353 checklist.append(OR(OptCheck('STRICT_DEVMEM', 'y', 'defconfig', 'cut_attack_surface'), \
354 devmem_not_set)) # refers to LOCK_DOWN_KERNEL
356 checklist.append(modules_not_set)
357 checklist.append(devmem_not_set)
358 checklist.append(OR(OptCheck('IO_STRICT_DEVMEM', 'y', 'kspp', 'cut_attack_surface'), \
359 devmem_not_set)) # refers to LOCK_DOWN_KERNEL
360 if debug_mode or arch == 'ARM':
361 checklist.append(OR(OptCheck('STRICT_DEVMEM', 'y', 'kspp', 'cut_attack_surface'), \
362 devmem_not_set)) # refers to LOCK_DOWN_KERNEL
363 checklist.append(OptCheck('ACPI_CUSTOM_METHOD', 'is not set', 'kspp', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
364 checklist.append(OptCheck('COMPAT_BRK', 'is not set', 'kspp', 'cut_attack_surface'))
365 checklist.append(OptCheck('DEVKMEM', 'is not set', 'kspp', 'cut_attack_surface'))
366 checklist.append(OptCheck('COMPAT_VDSO', 'is not set', 'kspp', 'cut_attack_surface'))
367 checklist.append(OptCheck('BINFMT_MISC', 'is not set', 'kspp', 'cut_attack_surface'))
368 checklist.append(OptCheck('INET_DIAG', 'is not set', 'kspp', 'cut_attack_surface'))
369 checklist.append(OptCheck('KEXEC', 'is not set', 'kspp', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
370 checklist.append(OptCheck('PROC_KCORE', 'is not set', 'kspp', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
371 checklist.append(OptCheck('LEGACY_PTYS', 'is not set', 'kspp', 'cut_attack_surface'))
372 checklist.append(OptCheck('HIBERNATION', 'is not set', 'kspp', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
373 if debug_mode or arch == 'X86_64':
374 checklist.append(OptCheck('LEGACY_VSYSCALL_NONE', 'y', 'kspp', 'cut_attack_surface')) # 'vsyscall=none'
375 checklist.append(OptCheck('IA32_EMULATION', 'is not set', 'kspp', 'cut_attack_surface'))
376 checklist.append(OptCheck('X86_X32', 'is not set', 'kspp', 'cut_attack_surface'))
377 checklist.append(OptCheck('MODIFY_LDT_SYSCALL', 'is not set', 'kspp', 'cut_attack_surface'))
378 if debug_mode or arch == 'ARM':
379 checklist.append(OptCheck('OABI_COMPAT', 'is not set', 'kspp', 'cut_attack_surface'))
381 checklist.append(OptCheck('X86_PTDUMP', 'is not set', 'grsecurity', 'cut_attack_surface'))
382 checklist.append(OptCheck('ZSMALLOC_STAT', 'is not set', 'grsecurity', 'cut_attack_surface'))
383 checklist.append(OptCheck('PAGE_OWNER', 'is not set', 'grsecurity', 'cut_attack_surface'))
384 checklist.append(OptCheck('DEBUG_KMEMLEAK', 'is not set', 'grsecurity', 'cut_attack_surface'))
385 checklist.append(OptCheck('BINFMT_AOUT', 'is not set', 'grsecurity', 'cut_attack_surface'))
386 checklist.append(OptCheck('KPROBES', 'is not set', 'grsecurity', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
387 checklist.append(OptCheck('UPROBES', 'is not set', 'grsecurity', 'cut_attack_surface'))
388 checklist.append(OptCheck('GENERIC_TRACER', 'is not set', 'grsecurity', 'cut_attack_surface'))
389 checklist.append(OptCheck('PROC_VMCORE', 'is not set', 'grsecurity', 'cut_attack_surface'))
390 checklist.append(OptCheck('PROC_PAGE_MONITOR', 'is not set', 'grsecurity', 'cut_attack_surface'))
391 checklist.append(OptCheck('USELIB', 'is not set', 'grsecurity', 'cut_attack_surface'))
392 checklist.append(OptCheck('CHECKPOINT_RESTORE', 'is not set', 'grsecurity', 'cut_attack_surface'))
393 checklist.append(OptCheck('USERFAULTFD', 'is not set', 'grsecurity', 'cut_attack_surface'))
394 checklist.append(OptCheck('HWPOISON_INJECT', 'is not set', 'grsecurity', 'cut_attack_surface'))
395 checklist.append(OptCheck('MEM_SOFT_DIRTY', 'is not set', 'grsecurity', 'cut_attack_surface'))
396 checklist.append(OptCheck('DEVPORT', 'is not set', 'grsecurity', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
397 checklist.append(OptCheck('DEBUG_FS', 'is not set', 'grsecurity', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
398 checklist.append(OptCheck('NOTIFIER_ERROR_INJECTION','is not set', 'grsecurity', 'cut_attack_surface'))
400 checklist.append(OptCheck('ACPI_TABLE_UPGRADE', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
401 checklist.append(OptCheck('ACPI_APEI_EINJ', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
402 checklist.append(OptCheck('PROFILING', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
403 checklist.append(OptCheck('BPF_SYSCALL', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
404 checklist.append(OptCheck('MMIOTRACE_TEST', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
406 checklist.append(OptCheck('KSM', 'is not set', 'clipos', 'cut_attack_surface')) # to prevent FLUSH+RELOAD attack
407 # checklist.append(OptCheck('IKCONFIG', 'is not set', 'clipos', 'cut_attack_surface')) # no, this info is needed for this check :)
408 checklist.append(OptCheck('KALLSYMS', 'is not set', 'clipos', 'cut_attack_surface'))
409 checklist.append(OptCheck('X86_VSYSCALL_EMULATION', 'is not set', 'clipos', 'cut_attack_surface'))
410 checklist.append(OptCheck('MAGIC_SYSRQ', 'is not set', 'clipos', 'cut_attack_surface'))
411 checklist.append(OptCheck('KEXEC_FILE', 'is not set', 'clipos', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL (permissive)
412 checklist.append(OptCheck('USER_NS', 'is not set', 'clipos', 'cut_attack_surface')) # user.max_user_namespaces=0
413 checklist.append(AND(OptCheck('LDISC_AUTOLOAD', 'is not set', 'clipos', 'cut_attack_surface'), \
414 VerCheck((5, 1)))) # LDISC_AUTOLOAD can be disabled since v5.1
416 checklist.append(OptCheck('MMIOTRACE', 'is not set', 'my', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL (permissive)
417 checklist.append(OptCheck('LIVEPATCH', 'is not set', 'my', 'cut_attack_surface'))
418 checklist.append(OptCheck('IP_DCCP', 'is not set', 'my', 'cut_attack_surface'))
419 checklist.append(OptCheck('IP_SCTP', 'is not set', 'my', 'cut_attack_surface'))
420 checklist.append(OptCheck('FTRACE', 'is not set', 'my', 'cut_attack_surface'))
421 checklist.append(OptCheck('BPF_JIT', 'is not set', 'my', 'cut_attack_surface'))
422 checklist.append(OptCheck('VIDEO_VIVID', 'is not set', 'my', 'cut_attack_surface'))
423 if debug_mode or arch == 'X86_32':
424 checklist.append(OptCheck('MODIFY_LDT_SYSCALL', 'is not set', 'my', 'cut_attack_surface'))
426 if debug_mode or arch == 'ARM64':
427 checklist.append(OptCheck('ARM64_PTR_AUTH', 'y', 'defconfig', 'userspace_hardening'))
428 if debug_mode or arch == 'X86_64' or arch == 'ARM64':
429 checklist.append(OptCheck('ARCH_MMAP_RND_BITS', '32', 'clipos', 'userspace_hardening'))
430 if debug_mode or arch == 'X86_32' or arch == 'ARM':
431 checklist.append(OptCheck('ARCH_MMAP_RND_BITS', '16', 'my', 'userspace_hardening'))
433 # checklist.append(OptCheck('LKDTM', 'm', 'my', 'feature_test'))
436 def print_checklist(checklist, with_results):
440 opt = ['CONFIG_'+o.name, o.expected, o.decision, o.reason]
444 print(json.dumps(opts))
451 print('=' * sep_line_len)
452 print('{:^45}|{:^13}|{:^10}|{:^20}'.format('option name', 'desired val', 'decision', 'reason'), end='')
454 print('| {}'.format('check result'), end='')
456 print('=' * sep_line_len)
458 for opt in checklist:
459 print('CONFIG_{:<38}|{:^13}|{:^10}|{:^20}'.format(opt.name, opt.expected, opt.decision, opt.reason), end='')
461 print('| {}'.format(opt.result), end='')
466 def perform_checks(checklist, parsed_options):
467 for opt in checklist:
468 if hasattr(opt, 'opts'):
469 # prepare ComplexOptCheck
471 if hasattr(o, 'name'):
472 o.state = parsed_options.get(o.name, None)
474 # prepare simple OptCheck
475 if not hasattr(opt, 'name'):
476 sys.exit('[!] ERROR: bad OptCheck {}'.format(vars(opt)))
477 opt.state = parsed_options.get(opt.name, None)
481 def check_config_file(checklist, fname):
482 with open(fname, 'r') as f:
483 parsed_options = OrderedDict()
484 opt_is_on = re.compile("CONFIG_[a-zA-Z0-9_]*=[a-zA-Z0-9_\"]*")
485 opt_is_off = re.compile("# CONFIG_[a-zA-Z0-9_]* is not set")
488 print('[+] Checking "{}" against hardening preferences...'.format(fname))
489 for line in f.readlines():
494 if opt_is_on.match(line):
495 option, value = line[7:].split('=', 1)
496 elif opt_is_off.match(line):
497 option, value = line[9:].split(' ', 1)
498 if value != 'is not set':
499 sys.exit('[!] ERROR: bad disabled config option "{}"'.format(line))
501 if option in parsed_options:
502 sys.exit('[!] ERROR: config option "{}" exists multiple times'.format(line))
504 if option is not None:
505 parsed_options[option] = value
507 perform_checks(checklist, parsed_options)
510 known_options = [opt.name for opt in checklist]
511 for option, value in parsed_options.items():
512 if option not in known_options:
513 print("DEBUG: dunno about option {} ({})".format(option, value))
515 print_checklist(checklist, True)
518 if __name__ == '__main__':
519 parser = ArgumentParser(description='Checks the hardening options in the Linux kernel config')
520 parser.add_argument('-p', '--print', choices=supported_archs,
521 help='print hardening preferences for selected architecture')
522 parser.add_argument('-c', '--config',
523 help='check the config_file against these preferences')
524 parser.add_argument('--debug', action='store_true',
525 help='enable internal debug mode')
526 parser.add_argument('--json', action='store_true',
527 help='print results in JSON format')
528 args = parser.parse_args()
534 if debug_mode and json_mode:
535 sys.exit('[!] ERROR: options --debug and --json cannot be used simultaneously')
538 arch, msg = detect_arch(args.config)
540 sys.exit('[!] ERROR: {}'.format(msg))
542 print('[+] Detected architecture: {}'.format(arch))
544 kernel_version, msg = detect_version(args.config)
545 if not kernel_version:
546 sys.exit('[!] ERROR: {}'.format(msg))
548 print('[+] Detected kernel version: {}.{}'.format(kernel_version[0], kernel_version[1]))
550 construct_checklist(config_checklist, arch)
551 check_config_file(config_checklist, args.config)
552 error_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), config_checklist)))
553 ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), config_checklist)))
557 print('[+] config check is finished: \'OK\' - {} / \'FAIL\' - {}'.format(ok_count, error_count))
562 construct_checklist(config_checklist, arch)
564 print('[+] Printing kernel hardening preferences for {}...'.format(arch))
565 print_checklist(config_checklist, False)