#
# This script helps me to check the Linux kernel Kconfig option list
-# against my hardening preferences for x86_64. Let the computers do their job!
+# against my hardening preferences for X86_64, ARM64, X86_32, and ARM.
+# Let the computers do their job!
#
# Author: Alexander Popov <alex.popov@linux.com>
#
#
# N.B. Hardening sysctl's:
# net.core.bpf_jit_harden
-#
-#
-# TODO: add hardening preferences for ARM
+# kptr_restrict=2
import sys
from argparse import ArgumentParser
debug_mode = False # set it to True to print the unknown options from the config
-supported_archs = [ 'X86_64' ]
+supported_archs = [ 'X86_64', 'X86_32', 'ARM64', 'ARM' ]
checklist = []
return '{} = {}'.format(self.name, self.state)
-class OR:
+class ComplexOptCheck:
def __init__(self, *opts):
self.opts = opts
self.result = None
- # self.opts[0] is the option which this OR-check is about.
- # Use case: OR(<X_is_hardened>, <X_is_disabled>)
-
@property
def name(self):
return self.opts[0].name
def reason(self):
return self.opts[0].reason
+
+class OR(ComplexOptCheck):
+ # self.opts[0] is the option which this OR-check is about.
+ # Use case:
+ # OR(<X_is_hardened>, <X_is_disabled>)
+ # OR(<X_is_hardened>, <X_is_hardened_old>)
+
def check(self):
+ if not self.opts:
+ sys.exit('[!] ERROR: invalid OR check')
+
for i, opt in enumerate(self.opts):
- result, msg = opt.check()
- if result:
+ ret, msg = opt.check()
+ if ret:
if i == 0:
self.result = opt.result
else:
- self.result = 'CONFIG_{}: {} ("{}")'.format(opt.name, opt.result, opt.expected)
+ self.result = 'OK: CONFIG_{} "{}"'.format(opt.name, opt.expected)
return True, self.result
self.result = self.opts[0].result
return False, self.result
+class AND(ComplexOptCheck):
+ # self.opts[0] is the option which this AND-check is about.
+ # Use case: AND(<suboption>, <main_option>)
+ # Suboption is not checked if checking of the main_option is failed.
+
+ def check(self):
+ for i, opt in reversed(list(enumerate(self.opts))):
+ ret, msg = opt.check()
+ if i == 0:
+ self.result = opt.result
+ return ret, self.result
+ elif not ret:
+ self.result = 'FAIL: CONFIG_{} is needed'.format(opt.name)
+ return False, self.result
+
+ sys.exit('[!] ERROR: invalid AND check')
+
+
def detect_arch(fname):
with open(fname, 'r') as f:
arch_pattern = re.compile("CONFIG_[a-zA-Z0-9_]*=y")
devmem_not_set = OptCheck('DEVMEM', 'is not set', 'kspp', 'cut_attack_surface') # refers to LOCK_DOWN_KERNEL
checklist.append(OptCheck('BUG', 'y', 'defconfig', 'self_protection'))
- checklist.append(OptCheck('PAGE_TABLE_ISOLATION', 'y', 'defconfig', 'self_protection'))
- checklist.append(OptCheck('RETPOLINE', 'y', 'defconfig', 'self_protection'))
- checklist.append(OptCheck('X86_SMAP', 'y', 'defconfig', 'self_protection'))
- checklist.append(OptCheck('X86_INTEL_UMIP', 'y', 'defconfig', 'self_protection'))
checklist.append(OR(OptCheck('STRICT_KERNEL_RWX', 'y', 'defconfig', 'self_protection'), \
OptCheck('DEBUG_RODATA', 'y', 'defconfig', 'self_protection'))) # before v4.11
- checklist.append(OptCheck('RANDOMIZE_BASE', 'y', 'defconfig', 'self_protection'))
- checklist.append(OptCheck('RANDOMIZE_MEMORY', 'y', 'defconfig', 'self_protection'))
checklist.append(OR(OptCheck('STACKPROTECTOR_STRONG', 'y', 'defconfig', 'self_protection'), \
OptCheck('CC_STACKPROTECTOR_STRONG', 'y', 'defconfig', 'self_protection')))
- checklist.append(OptCheck('VMAP_STACK', 'y', 'defconfig', 'self_protection'))
- checklist.append(OptCheck('THREAD_INFO_IN_TASK', 'y', 'defconfig', 'self_protection'))
checklist.append(OptCheck('SLUB_DEBUG', 'y', 'defconfig', 'self_protection'))
checklist.append(OR(OptCheck('STRICT_MODULE_RWX', 'y', 'defconfig', 'self_protection'), \
OptCheck('DEBUG_SET_MODULE_RONX', 'y', 'defconfig', 'self_protection'), \
modules_not_set)) # DEBUG_SET_MODULE_RONX was before v4.11
- checklist.append(OptCheck('SYN_COOKIES', 'y', 'defconfig', 'self_protection')) # another reason?
+ if debug_mode or arch == 'X86_64':
+ checklist.append(OptCheck('PAGE_TABLE_ISOLATION', 'y', 'defconfig', 'self_protection'))
+ checklist.append(OptCheck('RANDOMIZE_MEMORY', 'y', 'defconfig', 'self_protection'))
+ if debug_mode or arch == 'X86_64' or arch == 'X86_32':
+ checklist.append(OptCheck('RANDOMIZE_BASE', 'y', 'defconfig', 'self_protection'))
+ checklist.append(OptCheck('RETPOLINE', 'y', 'defconfig', 'self_protection'))
+ checklist.append(OptCheck('X86_SMAP', 'y', 'defconfig', 'self_protection'))
+ checklist.append(OptCheck('X86_INTEL_UMIP', 'y', 'defconfig', 'self_protection'))
+ checklist.append(OptCheck('SYN_COOKIES', 'y', 'defconfig', 'self_protection')) # another reason?
+ if debug_mode or arch == 'ARM64':
+ checklist.append(OptCheck('UNMAP_KERNEL_AT_EL0', 'y', 'defconfig', 'self_protection'))
+ if debug_mode or arch == 'X86_64' or arch == 'ARM64':
+ checklist.append(OptCheck('VMAP_STACK', 'y', 'defconfig', 'self_protection'))
+ if debug_mode or arch == 'X86_64' or arch == 'ARM64' or arch == 'X86_32':
+ checklist.append(OptCheck('THREAD_INFO_IN_TASK', 'y', 'defconfig', 'self_protection'))
+ if debug_mode or arch == 'ARM':
+ checklist.append(OptCheck('VMSPLIT_3G', 'y', 'defconfig', 'self_protection'))
+ checklist.append(OptCheck('CPU_SW_DOMAIN_PAN', 'y', 'defconfig', 'self_protection'))
+ if debug_mode or arch == 'ARM64' or arch == 'ARM':
+ checklist.append(OptCheck('REFCOUNT_FULL', 'y', 'defconfig', 'self_protection'))
checklist.append(OptCheck('BUG_ON_DATA_CORRUPTION', 'y', 'kspp', 'self_protection'))
checklist.append(OptCheck('DEBUG_WX', 'y', 'kspp', 'self_protection'))
checklist.append(OptCheck('SCHED_STACK_END_CHECK', 'y', 'kspp', 'self_protection'))
- checklist.append(OptCheck('PAGE_POISONING', 'y', 'kspp', 'self_protection'))
checklist.append(OptCheck('SLAB_FREELIST_HARDENED', 'y', 'kspp', 'self_protection'))
checklist.append(OptCheck('SLAB_FREELIST_RANDOM', 'y', 'kspp', 'self_protection'))
- checklist.append(OptCheck('HARDENED_USERCOPY', 'y', 'kspp', 'self_protection'))
- checklist.append(OptCheck('HARDENED_USERCOPY_FALLBACK', 'is not set', 'kspp', 'self_protection'))
checklist.append(OptCheck('FORTIFY_SOURCE', 'y', 'kspp', 'self_protection'))
checklist.append(OptCheck('GCC_PLUGINS', 'y', 'kspp', 'self_protection'))
checklist.append(OptCheck('GCC_PLUGIN_RANDSTRUCT', 'y', 'kspp', 'self_protection'))
checklist.append(OptCheck('GCC_PLUGIN_STRUCTLEAK', 'y', 'kspp', 'self_protection'))
checklist.append(OptCheck('GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y', 'kspp', 'self_protection'))
checklist.append(OptCheck('GCC_PLUGIN_LATENT_ENTROPY', 'y', 'kspp', 'self_protection'))
- checklist.append(OptCheck('REFCOUNT_FULL', 'y', 'kspp', 'self_protection'))
checklist.append(OptCheck('DEBUG_LIST', 'y', 'kspp', 'self_protection'))
checklist.append(OptCheck('DEBUG_SG', 'y', 'kspp', 'self_protection'))
checklist.append(OptCheck('DEBUG_CREDENTIALS', 'y', 'kspp', 'self_protection'))
checklist.append(OptCheck('DEBUG_NOTIFIERS', 'y', 'kspp', 'self_protection'))
+ page_poisoning_is_set = OptCheck('PAGE_POISONING', 'y', 'kspp', 'self_protection')
+ checklist.append(page_poisoning_is_set)
+ hardened_usercopy_is_set = OptCheck('HARDENED_USERCOPY', 'y', 'kspp', 'self_protection')
+ checklist.append(hardened_usercopy_is_set)
+ checklist.append(AND(OptCheck('HARDENED_USERCOPY_FALLBACK', 'is not set', 'kspp', 'self_protection'), \
+ hardened_usercopy_is_set))
checklist.append(OR(OptCheck('MODULE_SIG', 'y', 'kspp', 'self_protection'), \
modules_not_set))
checklist.append(OR(OptCheck('MODULE_SIG_ALL', 'y', 'kspp', 'self_protection'), \
modules_not_set))
checklist.append(OR(OptCheck('MODULE_SIG_SHA512', 'y', 'kspp', 'self_protection'), \
modules_not_set))
- checklist.append(OptCheck('MODULE_SIG_FORCE', 'y', 'kspp', 'self_protection')) # refers to LOCK_DOWN_KERNEL
- checklist.append(OptCheck('DEFAULT_MMAP_MIN_ADDR', '65536', 'kspp', 'self_protection'))
-
- checklist.append(OptCheck('GCC_PLUGIN_STACKLEAK', 'y', 'my', 'self_protection'))
+ checklist.append(OR(OptCheck('MODULE_SIG_FORCE', 'y', 'kspp', 'self_protection'), \
+ modules_not_set)) # refers to LOCK_DOWN_KERNEL
+ if debug_mode or arch == 'X86_64' or arch == 'X86_32':
+ checklist.append(OptCheck('DEFAULT_MMAP_MIN_ADDR', '65536', 'kspp', 'self_protection'))
+ checklist.append(OptCheck('REFCOUNT_FULL', 'y', 'kspp', 'self_protection'))
+ if debug_mode or arch == 'X86_32':
+ checklist.append(OptCheck('HIGHMEM64G', 'y', 'kspp', 'self_protection'))
+ checklist.append(OptCheck('X86_PAE', 'y', 'kspp', 'self_protection'))
+ if debug_mode or arch == 'ARM64':
+ checklist.append(OptCheck('ARM64_SW_TTBR0_PAN', 'y', 'kspp', 'self_protection'))
+ checklist.append(OptCheck('RANDOMIZE_BASE', 'y', 'kspp', 'self_protection'))
+ if debug_mode or arch == 'ARM64' or arch == 'ARM':
+ checklist.append(OptCheck('SYN_COOKIES', 'y', 'kspp', 'self_protection')) # another reason?
+ checklist.append(OptCheck('DEFAULT_MMAP_MIN_ADDR', '32768', 'kspp', 'self_protection'))
+
+ if debug_mode or arch == 'X86_64' or arch == 'ARM64' or arch == 'X86_32':
+ checklist.append(OptCheck('GCC_PLUGIN_STACKLEAK', 'y', 'my', 'self_protection'))
checklist.append(OptCheck('LOCK_DOWN_KERNEL', 'y', 'my', 'self_protection')) # remember about LOCK_DOWN_MANDATORY
checklist.append(OptCheck('SLUB_DEBUG_ON', 'y', 'my', 'self_protection'))
checklist.append(OptCheck('SECURITY_DMESG_RESTRICT', 'y', 'my', 'self_protection'))
- checklist.append(OptCheck('STATIC_USERMODEHELPER', 'y', 'my', 'self_protection')) # breaks systemd?
- checklist.append(OptCheck('SECURITY_LOADPIN', 'y', 'my', 'self_protection'))
- checklist.append(OptCheck('PAGE_POISONING_NO_SANITY', 'is not set', 'my', 'self_protection'))
- checklist.append(OptCheck('PAGE_POISONING_ZERO', 'is not set', 'my', 'self_protection'))
+ checklist.append(OptCheck('STATIC_USERMODEHELPER', 'y', 'my', 'self_protection')) # needs userspace support (systemd)
+ checklist.append(OptCheck('SECURITY_LOADPIN', 'y', 'my', 'self_protection')) # needs userspace support
+ checklist.append(OptCheck('RESET_ATTACK_MITIGATION', 'y', 'my', 'self_protection')) # needs userspace support (systemd)
checklist.append(OptCheck('SLAB_MERGE_DEFAULT', 'is not set', 'my', 'self_protection')) # slab_nomerge
-
- checklist.append(OptCheck('SECURITY', 'y', 'defconfig', 'security_policy'))
+ checklist.append(AND(OptCheck('PAGE_POISONING_NO_SANITY', 'is not set', 'my', 'self_protection'), \
+ page_poisoning_is_set))
+ checklist.append(AND(OptCheck('PAGE_POISONING_ZERO', 'is not set', 'my', 'self_protection'), \
+ page_poisoning_is_set))
+ if debug_mode or arch == 'X86_32':
+ checklist.append(OptCheck('PAGE_TABLE_ISOLATION', 'y', 'my', 'self_protection'))
+ if debug_mode or arch == 'ARM':
+ checklist.append(OptCheck('STACKPROTECTOR_PER_TASK', 'y', 'my', 'self_protection'))
+
+ if debug_mode or arch == 'X86_64' or arch == 'ARM64' or arch == 'X86_32':
+ checklist.append(OptCheck('SECURITY', 'y', 'defconfig', 'security_policy'))
+ if debug_mode or arch == 'ARM':
+ checklist.append(OptCheck('SECURITY', 'y', 'kspp', 'security_policy'))
checklist.append(OptCheck('SECURITY_YAMA', 'y', 'kspp', 'security_policy'))
checklist.append(OptCheck('SECURITY_SELINUX_DISABLE', 'is not set', 'kspp', 'security_policy'))
checklist.append(OptCheck('SECCOMP', 'y', 'defconfig', 'cut_attack_surface'))
checklist.append(OptCheck('SECCOMP_FILTER', 'y', 'defconfig', 'cut_attack_surface'))
- checklist.append(OR(OptCheck('STRICT_DEVMEM', 'y', 'defconfig', 'cut_attack_surface'), \
- devmem_not_set)) # refers to LOCK_DOWN_KERNEL
+ if debug_mode or arch == 'X86_64' or arch == 'ARM64' or arch == 'X86_32':
+ checklist.append(OR(OptCheck('STRICT_DEVMEM', 'y', 'defconfig', 'cut_attack_surface'), \
+ devmem_not_set)) # refers to LOCK_DOWN_KERNEL
+ checklist.append(modules_not_set)
+ checklist.append(devmem_not_set)
checklist.append(OR(OptCheck('IO_STRICT_DEVMEM', 'y', 'kspp', 'cut_attack_surface'), \
devmem_not_set)) # refers to LOCK_DOWN_KERNEL
- checklist.append(OptCheck('LEGACY_VSYSCALL_NONE', 'y', 'kspp', 'cut_attack_surface')) # 'vsyscall=none'
+ if debug_mode or arch == 'ARM':
+ checklist.append(OR(OptCheck('STRICT_DEVMEM', 'y', 'kspp', 'cut_attack_surface'), \
+ devmem_not_set)) # refers to LOCK_DOWN_KERNEL
checklist.append(OptCheck('ACPI_CUSTOM_METHOD', 'is not set', 'kspp', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
checklist.append(OptCheck('COMPAT_BRK', 'is not set', 'kspp', 'cut_attack_surface'))
checklist.append(OptCheck('DEVKMEM', 'is not set', 'kspp', 'cut_attack_surface'))
checklist.append(OptCheck('KEXEC', 'is not set', 'kspp', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
checklist.append(OptCheck('PROC_KCORE', 'is not set', 'kspp', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
checklist.append(OptCheck('LEGACY_PTYS', 'is not set', 'kspp', 'cut_attack_surface'))
- checklist.append(OptCheck('IA32_EMULATION', 'is not set', 'kspp', 'cut_attack_surface'))
- checklist.append(OptCheck('X86_X32', 'is not set', 'kspp', 'cut_attack_surface'))
- checklist.append(OptCheck('MODIFY_LDT_SYSCALL', 'is not set', 'kspp', 'cut_attack_surface'))
checklist.append(OptCheck('HIBERNATION', 'is not set', 'kspp', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
+ if debug_mode or arch == 'X86_64':
+ checklist.append(OptCheck('LEGACY_VSYSCALL_NONE', 'y', 'kspp', 'cut_attack_surface')) # 'vsyscall=none'
+ checklist.append(OptCheck('IA32_EMULATION', 'is not set', 'kspp', 'cut_attack_surface'))
+ checklist.append(OptCheck('X86_X32', 'is not set', 'kspp', 'cut_attack_surface'))
+ checklist.append(OptCheck('MODIFY_LDT_SYSCALL', 'is not set', 'kspp', 'cut_attack_surface'))
+ if debug_mode or arch == 'ARM':
+ checklist.append(OptCheck('OABI_COMPAT', 'is not set', 'kspp', 'cut_attack_surface'))
checklist.append(OptCheck('X86_PTDUMP', 'is not set', 'grsecurity', 'cut_attack_surface'))
checklist.append(OptCheck('ZSMALLOC_STAT', 'is not set', 'grsecurity', 'cut_attack_surface'))
checklist.append(OptCheck('IP_SCTP', 'is not set', 'my', 'cut_attack_surface'))
checklist.append(OptCheck('FTRACE', 'is not set', 'my', 'cut_attack_surface'))
checklist.append(OptCheck('BPF_JIT', 'is not set', 'my', 'cut_attack_surface'))
+ if debug_mode or arch == 'X86_32':
+ checklist.append(OptCheck('MODIFY_LDT_SYSCALL', 'is not set', 'my', 'cut_attack_surface'))
- checklist.append(OptCheck('ARCH_MMAP_RND_BITS', '32', 'my', 'userspace_protection'))
+ if debug_mode or arch == 'ARM64':
+ checklist.append(OptCheck('ARM64_PTR_AUTH', 'y', 'defconfig', 'userspace_protection'))
+ if debug_mode or arch == 'X86_64' or arch == 'ARM64':
+ checklist.append(OptCheck('ARCH_MMAP_RND_BITS', '32', 'my', 'userspace_protection'))
+ if debug_mode or arch == 'X86_32' or arch == 'ARM':
+ checklist.append(OptCheck('ARCH_MMAP_RND_BITS', '16', 'my', 'userspace_protection'))
# checklist.append(OptCheck('LKDTM', 'm', 'my', 'feature_test'))
construct_checklist(arch)
check_config_file(args.config)
error_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), checklist)))
- if error_count == 0:
- print('[+] config check is PASSED')
+ ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), checklist)))
+ if debug_mode:
sys.exit(0)
- else:
- sys.exit('[-] config check is NOT PASSED: {} errors'.format(error_count))
+ print('[+] config check is finished: \'OK\' - {} / \'FAIL\' - {}'.format(ok_count, error_count))
+ sys.exit(0)
if args.print:
arch = args.print
projects / kconfig-hardened-check.git / blobdiff