#!/usr/bin/python3
#
# This script helps me to check the Linux kernel Kconfig option list
# 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>
#
# Please don't cry if my Python code looks like C.
#
#
# N.B Hardening command line parameters:
# slub_debug=FZP
# slab_nomerge
# kernel.kptr_restrict=1
# lockdown=1 (is it changed?)
# page_alloc.shuffle=1
# iommu=force (does it help against DMA attacks?)
# page_poison=1 (if enabled)
#
# Mitigations of CPU vulnerabilities:
# Аrch-independent:
# mitigations=auto,nosmt
# X86:
# spectre_v2=on
# pti=on
# spec_store_bypass_disable=on
# l1tf=full,force
# mds=full,nosmt
# ARM64:
# kpti=on
# ssbd=force-on
#
# N.B. Hardening sysctls:
# net.core.bpf_jit_harden=2
# kptr_restrict=2
# vm.unprivileged_userfaultfd=0
# kernel.perf_event_paranoid=3
# kernel.yama.ptrace_scope=1 (or even 3?)
# kernel.unprivileged_bpf_disabled=1
# fs.suid_dumpable=0
# fs.protected_symlinks = 1
# fs.protected_hardlinks = 1
# fs.protected_fifos = 2
# fs.protected_regular = 2
import sys
from argparse import ArgumentParser
from collections import OrderedDict
import re
import json
debug_mode = False # set it to True to print the unknown options from the config
json_mode = False # if True, print results in JSON format
supported_archs = [ 'X86_64', 'X86_32', 'ARM64', 'ARM' ]
class OptCheck:
def __init__(self, name, expected, decision, reason):
self.name = name
self.expected = expected
self.decision = decision
self.reason = reason
self.state = None
self.result = None
def check(self):
if self.expected == self.state:
self.result = 'OK'
elif self.state is None:
if self.expected == 'is not set':
self.result = 'OK: not found'
else:
self.result = 'FAIL: not found'
else:
self.result = 'FAIL: "' + self.state + '"'
if self.result.startswith('OK'):
return True, self.result
else:
return False, self.result
def __repr__(self):
return '{} = {}'.format(self.name, self.state)
class ComplexOptCheck:
def __init__(self, *opts):
self.opts = opts
self.result = None
@property
def name(self):
return self.opts[0].name
@property
def expected(self):
return self.opts[0].expected
@property
def state(self):
return self.opts[0].state
@property
def decision(self):
return self.opts[0].decision
@property
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):
ret, msg = opt.check()
if ret:
if i == 0:
self.result = opt.result
else:
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")
arch = None
msg = None
if not json_mode:
print('[+] Trying to detect architecture in "{}"...'.format(fname))
for line in f.readlines():
if arch_pattern.match(line):
option, value = line[7:].split('=', 1)
if option in supported_archs:
if not arch:
arch = option
else:
return None, 'more than one supported architecture is detected'
if not arch:
return None, 'failed to detect architecture'
else:
return arch, 'OK'
def construct_checklist(checklist, arch):
modules_not_set = OptCheck('MODULES', 'is not set', 'kspp', 'cut_attack_surface')
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(OR(OptCheck('STRICT_KERNEL_RWX', 'y', 'defconfig', 'self_protection'), \
OptCheck('DEBUG_RODATA', 'y', 'defconfig', 'self_protection'))) # before v4.11
checklist.append(OR(OptCheck('STACKPROTECTOR_STRONG', 'y', 'defconfig', 'self_protection'), \
OptCheck('CC_STACKPROTECTOR_STRONG', '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
if debug_mode or arch == 'X86_64' or arch == 'X86_32':
checklist.append(OptCheck('MICROCODE', 'y', 'defconfig', 'self_protection')) # is needed for mitigating CPU bugs
checklist.append(OptCheck('RETPOLINE', 'y', 'defconfig', 'self_protection'))
checklist.append(OptCheck('X86_SMAP', 'y', 'defconfig', 'self_protection'))
checklist.append(OR(OptCheck('X86_UMIP', 'y', 'defconfig', 'self_protection'), \
OptCheck('X86_INTEL_UMIP', 'y', 'defconfig', 'self_protection')))
iommu_support_is_set = OptCheck('IOMMU_SUPPORT', 'y', 'defconfig', 'self_protection') # is needed for mitigating DMA attacks
checklist.append(iommu_support_is_set)
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'))
checklist.append(AND(OptCheck('INTEL_IOMMU', 'y', 'defconfig', 'self_protection'), \
iommu_support_is_set))
checklist.append(AND(OptCheck('AMD_IOMMU', 'y', 'defconfig', 'self_protection'), \
iommu_support_is_set))
if debug_mode or arch == 'ARM64':
checklist.append(OptCheck('UNMAP_KERNEL_AT_EL0', 'y', 'defconfig', 'self_protection'))
checklist.append(OptCheck('HARDEN_EL2_VECTORS', 'y', 'defconfig', 'self_protection'))
checklist.append(OptCheck('RODATA_FULL_DEFAULT_ENABLED', '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('RANDOMIZE_BASE', 'y', 'defconfig', 'self_protection'))
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('HARDEN_BRANCH_PREDICTOR', '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('SLAB_FREELIST_HARDENED', 'y', 'kspp', 'self_protection'))
checklist.append(OptCheck('SLAB_FREELIST_RANDOM', 'y', 'kspp', 'self_protection'))
checklist.append(OptCheck('SHUFFLE_PAGE_ALLOCATOR', 'y', 'kspp', 'self_protection'))
checklist.append(OptCheck('FORTIFY_SOURCE', 'y', 'kspp', 'self_protection'))
checklist.append(OptCheck('GCC_PLUGINS', 'y', 'kspp', 'self_protection'))
randstruct_is_set = OptCheck('GCC_PLUGIN_RANDSTRUCT', 'y', 'kspp', 'self_protection')
checklist.append(randstruct_is_set)
checklist.append(OptCheck('GCC_PLUGIN_LATENT_ENTROPY', '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'))
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(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'))
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'))
checklist.append(OR(OptCheck('INIT_STACK_ALL', 'y', 'clipos', 'self_protection'), \
OptCheck('GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y', 'kspp', 'self_protection')))
checklist.append(OptCheck('INIT_ON_ALLOC_DEFAULT_ON', 'y', 'clipos', 'self_protection'))
checklist.append(OR(OptCheck('INIT_ON_FREE_DEFAULT_ON', 'y', 'clipos', 'self_protection'), \
OptCheck('PAGE_POISONING', 'y', 'kspp', 'self_protection')))
checklist.append(OptCheck('SECURITY_DMESG_RESTRICT', 'y', 'clipos', 'self_protection'))
checklist.append(OptCheck('DEBUG_VIRTUAL', 'y', 'clipos', 'self_protection'))
checklist.append(OptCheck('STATIC_USERMODEHELPER', 'y', 'clipos', 'self_protection')) # needs userspace support (systemd)
checklist.append(OptCheck('SLAB_MERGE_DEFAULT', 'is not set', 'clipos', 'self_protection')) # slab_nomerge
checklist.append(AND(OptCheck('GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set', 'clipos', 'self_protection'), \
randstruct_is_set))
if debug_mode or arch == 'X86_64' or arch == 'ARM64' or arch == 'X86_32':
stackleak_is_set = OptCheck('GCC_PLUGIN_STACKLEAK', 'y', 'clipos', 'self_protection')
checklist.append(stackleak_is_set)
checklist.append(AND(OptCheck('STACKLEAK_METRICS', 'is not set', 'clipos', 'self_protection'), \
stackleak_is_set))
checklist.append(AND(OptCheck('STACKLEAK_RUNTIME_DISABLE', 'is not set', 'clipos', 'self_protection'), \
stackleak_is_set))
if debug_mode or arch == 'X86_64' or arch == 'X86_32':
checklist.append(OptCheck('RANDOM_TRUST_CPU', 'is not set', 'clipos', 'self_protection'))
checklist.append(AND(OptCheck('INTEL_IOMMU_SVM', 'y', 'clipos', 'self_protection'), \
iommu_support_is_set))
checklist.append(AND(OptCheck('INTEL_IOMMU_DEFAULT_ON', 'y', 'clipos', 'self_protection'), \
iommu_support_is_set))
checklist.append(OptCheck('SLUB_DEBUG_ON', 'y', 'my', 'self_protection'))
checklist.append(OptCheck('RESET_ATTACK_MITIGATION', 'y', 'my', 'self_protection')) # needs userspace support (systemd)
if debug_mode or arch == 'X86_64':
checklist.append(AND(OptCheck('AMD_IOMMU_V2', 'y', 'my', 'self_protection'), \
iommu_support_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')) # and choose your favourite LSM
if debug_mode or arch == 'ARM':
checklist.append(OptCheck('SECURITY', 'y', 'kspp', 'security_policy')) # and choose your favourite LSM
checklist.append(OptCheck('SECURITY_WRITABLE_HOOKS', 'is not set', 'defconfig', 'security_policy'))
checklist.append(OptCheck('SECURITY_YAMA', 'y', 'kspp', 'security_policy'))
checklist.append(OptCheck('SECURITY_LOADPIN', 'y', 'my', 'security_policy')) # needs userspace support
checklist.append(OptCheck('SECURITY_LOCKDOWN_LSM', 'y', 'my', 'security_policy'))
checklist.append(OptCheck('SECURITY_LOCKDOWN_LSM_EARLY', 'y', 'my', 'security_policy'))
checklist.append(OptCheck('LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y', 'my', 'security_policy'))
checklist.append(OptCheck('SECURITY_SAFESETID', 'y', 'my', 'security_policy'))
checklist.append(OptCheck('SECCOMP', 'y', 'defconfig', 'cut_attack_surface'))
checklist.append(OptCheck('SECCOMP_FILTER', 'y', 'defconfig', 'cut_attack_surface'))
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
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('COMPAT_VDSO', 'is not set', 'kspp', 'cut_attack_surface'))
checklist.append(OptCheck('BINFMT_MISC', 'is not set', 'kspp', 'cut_attack_surface'))
checklist.append(OptCheck('INET_DIAG', '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('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('PAGE_OWNER', 'is not set', 'grsecurity', 'cut_attack_surface'))
checklist.append(OptCheck('DEBUG_KMEMLEAK', 'is not set', 'grsecurity', 'cut_attack_surface'))
checklist.append(OptCheck('BINFMT_AOUT', 'is not set', 'grsecurity', 'cut_attack_surface'))
checklist.append(OptCheck('KPROBES', 'is not set', 'grsecurity', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
checklist.append(OptCheck('UPROBES', 'is not set', 'grsecurity', 'cut_attack_surface'))
checklist.append(OptCheck('GENERIC_TRACER', 'is not set', 'grsecurity', 'cut_attack_surface'))
checklist.append(OptCheck('PROC_VMCORE', 'is not set', 'grsecurity', 'cut_attack_surface'))
checklist.append(OptCheck('PROC_PAGE_MONITOR', 'is not set', 'grsecurity', 'cut_attack_surface'))
checklist.append(OptCheck('USELIB', 'is not set', 'grsecurity', 'cut_attack_surface'))
checklist.append(OptCheck('CHECKPOINT_RESTORE', 'is not set', 'grsecurity', 'cut_attack_surface'))
checklist.append(OptCheck('USERFAULTFD', 'is not set', 'grsecurity', 'cut_attack_surface'))
checklist.append(OptCheck('HWPOISON_INJECT', 'is not set', 'grsecurity', 'cut_attack_surface'))
checklist.append(OptCheck('MEM_SOFT_DIRTY', 'is not set', 'grsecurity', 'cut_attack_surface'))
checklist.append(OptCheck('DEVPORT', 'is not set', 'grsecurity', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
checklist.append(OptCheck('DEBUG_FS', 'is not set', 'grsecurity', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
checklist.append(OptCheck('NOTIFIER_ERROR_INJECTION','is not set', 'grsecurity', 'cut_attack_surface'))
checklist.append(OptCheck('ACPI_TABLE_UPGRADE', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
checklist.append(OptCheck('ACPI_APEI_EINJ', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
checklist.append(OptCheck('PROFILING', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
checklist.append(OptCheck('BPF_SYSCALL', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
checklist.append(OptCheck('MMIOTRACE_TEST', 'is not set', 'lockdown', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL
checklist.append(OptCheck('KSM', 'is not set', 'clipos', 'cut_attack_surface')) # to prevent FLUSH+RELOAD attack
# checklist.append(OptCheck('IKCONFIG', 'is not set', 'clipos', 'cut_attack_surface')) # no, this info is needed for this check :)
checklist.append(OptCheck('KALLSYMS', 'is not set', 'clipos', 'cut_attack_surface'))
checklist.append(OptCheck('X86_VSYSCALL_EMULATION', 'is not set', 'clipos', 'cut_attack_surface'))
checklist.append(OptCheck('MAGIC_SYSRQ', 'is not set', 'clipos', 'cut_attack_surface'))
checklist.append(OptCheck('KEXEC_FILE', 'is not set', 'clipos', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL (permissive)
checklist.append(OptCheck('USER_NS', 'is not set', 'clipos', 'cut_attack_surface')) # user.max_user_namespaces=0
checklist.append(OptCheck('LDISC_AUTOLOAD', 'is not set', 'clipos', 'cut_attack_surface'))
checklist.append(OptCheck('MMIOTRACE', 'is not set', 'my', 'cut_attack_surface')) # refers to LOCK_DOWN_KERNEL (permissive)
checklist.append(OptCheck('LIVEPATCH', 'is not set', 'my', 'cut_attack_surface'))
checklist.append(OptCheck('IP_DCCP', 'is not set', 'my', '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'))
checklist.append(OptCheck('VIDEO_VIVID', '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'))
if debug_mode or arch == 'ARM64':
checklist.append(OptCheck('ARM64_PTR_AUTH', 'y', 'defconfig', 'userspace_hardening'))
if debug_mode or arch == 'X86_64' or arch == 'ARM64':
checklist.append(OptCheck('ARCH_MMAP_RND_BITS', '32', 'clipos', 'userspace_hardening'))
if debug_mode or arch == 'X86_32' or arch == 'ARM':
checklist.append(OptCheck('ARCH_MMAP_RND_BITS', '16', 'my', 'userspace_hardening'))
# checklist.append(OptCheck('LKDTM', 'm', 'my', 'feature_test'))
def print_checklist(checklist, with_results):
if json_mode:
opts = []
for o in checklist:
opt = ['CONFIG_'+o.name, o.expected, o.decision, o.reason]
if with_results:
opt.append(o.result)
opts.append(opt)
print(json.dumps(opts))
return
# header
print('{:^45}|{:^13}|{:^10}|{:^20}'.format('option name', 'desired val', 'decision', 'reason'), end='')
sep_line_len = 91
if with_results:
print('| {}'.format('check result'), end='')
sep_line_len += 30
print()
print('=' * sep_line_len)
for opt in checklist:
print('CONFIG_{:<38}|{:^13}|{:^10}|{:^20}'.format(opt.name, opt.expected, opt.decision, opt.reason), end='')
if with_results:
print('| {}'.format(opt.result), end='')
print()
print()
def get_option_state(options, name):
return options.get(name, None)
def perform_checks(checklist, parsed_options):
for opt in checklist:
if hasattr(opt, 'opts'):
for o in opt.opts:
o.state = get_option_state(parsed_options, o.name)
else:
opt.state = get_option_state(parsed_options, opt.name)
opt.check()
def check_config_file(checklist, fname):
with open(fname, 'r') as f:
parsed_options = OrderedDict()
opt_is_on = re.compile("CONFIG_[a-zA-Z0-9_]*=[a-zA-Z0-9_\"]*")
opt_is_off = re.compile("# CONFIG_[a-zA-Z0-9_]* is not set")
if not json_mode:
print('[+] Checking "{}" against hardening preferences...'.format(fname))
for line in f.readlines():
line = line.strip()
option = None
value = None
if opt_is_on.match(line):
option, value = line[7:].split('=', 1)
elif opt_is_off.match(line):
option, value = line[9:].split(' ', 1)
if value != 'is not set':
sys.exit('[!] ERROR: bad disabled config option "{}"'.format(line))
if option in parsed_options:
sys.exit('[!] ERROR: config option "{}" exists multiple times'.format(line))
if option is not None:
parsed_options[option] = value
perform_checks(checklist, parsed_options)
if debug_mode:
known_options = [opt.name for opt in checklist]
for option, value in parsed_options.items():
if option not in known_options:
print("DEBUG: dunno about option {} ({})".format(option, value))
print_checklist(checklist, True)
if __name__ == '__main__':
config_checklist = []
parser = ArgumentParser(description='Checks the hardening options in the Linux kernel config')
parser.add_argument('-p', '--print', choices=supported_archs,
help='print hardening preferences for selected architecture')
parser.add_argument('-c', '--config',
help='check the config_file against these preferences')
parser.add_argument('--debug', action='store_true',
help='enable internal debug mode')
parser.add_argument('--json', action='store_true',
help='print results in JSON format')
args = parser.parse_args()
if args.debug:
debug_mode = True
if args.json:
json_mode = True
if debug_mode and json_mode:
sys.exit('[!] ERROR: options --debug and --json cannot be used simultaneously')
if args.config:
arch, msg = detect_arch(args.config)
if not arch:
sys.exit('[!] ERROR: {}'.format(msg))
elif not json_mode:
print('[+] Detected architecture: {}'.format(arch))
construct_checklist(config_checklist, arch)
check_config_file(config_checklist, args.config)
error_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), config_checklist)))
ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), config_checklist)))
if debug_mode:
sys.exit(0)
if not json_mode:
print('[+] config check is finished: \'OK\' - {} / \'FAIL\' - {}'.format(ok_count, error_count))
sys.exit(0)
if args.print:
arch = args.print
construct_checklist(config_checklist, arch)
if not json_mode:
print('[+] Printing kernel hardening preferences for {}...'.format(arch))
print_checklist(config_checklist, False)
sys.exit(0)
parser.print_help()