#!/usr/bin/python3
-#
-# This tool helps me to check Linux kernel options against
-# my security 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:
-# iommu=force (does it help against DMA attacks?)
-# loadpin.enforce=1
-#
-# Mitigations of CPU vulnerabilities:
-# Аrch-independent:
-# mitigations=auto,nosmt (nosmt is slow)
-# X86:
-# spectre_v2=on
-# spec_store_bypass_disable=on
-# l1tf=full,force
-# l1d_flush=on (a part of the l1tf option)
-# mds=full,nosmt
-# tsx=off
-# ARM64:
-# kpti=on
-# ssbd=force-on
-#
-# Should NOT be set:
-# sysrq_always_enabled
-# arm64.nobti
-# arm64.nopauth
-# arm64.nomte
-#
-# Hardware tag-based KASAN with arm64 Memory Tagging Extension (MTE):
-# kasan=on
-# kasan.stacktrace=off
-# kasan.fault=panic
-#
-# N.B. Hardening sysctls:
-# kernel.kptr_restrict=2 (or 1?)
-# kernel.dmesg_restrict=1 (also see the kconfig option)
-# kernel.perf_event_paranoid=3
-# kernel.kexec_load_disabled=1
-# kernel.yama.ptrace_scope=3
-# user.max_user_namespaces=0
-# what about bpf_jit_enable?
-# kernel.unprivileged_bpf_disabled=1
-# net.core.bpf_jit_harden=2
-# vm.unprivileged_userfaultfd=0
-# (at first, it disabled unprivileged userfaultfd,
-# and since v5.11 it enables unprivileged userfaultfd for user-mode only)
-# vm.mmap_min_addr has a good value
-# dev.tty.ldisc_autoload=0
-# fs.protected_symlinks=1
-# fs.protected_hardlinks=1
-# fs.protected_fifos=2
-# fs.protected_regular=2
-# fs.suid_dumpable=0
-# kernel.modules_disabled=1
-# kernel.randomize_va_space = 2
+"""
+This tool is for checking the security hardening options of the Linux kernel.
+Author: Alexander Popov <alex.popov@linux.com>
-# pylint: disable=missing-module-docstring,missing-class-docstring,missing-function-docstring
-# pylint: disable=line-too-long,invalid-name,too-many-branches,too-many-statements
+This module performs input/output.
+"""
+# pylint: disable=missing-function-docstring,line-too-long,invalid-name,too-many-branches,too-many-statements
+import gzip
import sys
from argparse import ArgumentParser
from collections import OrderedDict
import re
import json
from .__about__ import __version__
+from .checks import add_kconfig_checks, add_cmdline_checks, normalize_cmdline_options, add_sysctl_checks
+from .engine import populate_with_data, perform_checks, override_expected_value
-SIMPLE_OPTION_TYPES = ('kconfig', 'version', 'cmdline')
-class OptCheck:
- # Constructor without the 'expected' parameter is for option presence checks (any value is OK)
- def __init__(self, reason, decision, name, expected=None):
- assert(reason and decision and name), \
- 'invalid {} check for "{}"'.format(self.__class__.__name__, name)
- self.name = name
- self.expected = expected
- self.decision = decision
- self.reason = reason
- self.state = None
- self.result = None
+def _open(file: str, *args, **kwargs):
+ open_method = open
+ if file.endswith(".gz"):
+ open_method = gzip.open
- @property
- def type(self):
- return None
-
- def check(self):
- # handle the option presence check
- if self.expected is None:
- if self.state is None:
- self.result = 'FAIL: not present'
- else:
- self.result = 'OK: is present'
- return
-
- # handle the option value check
- 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 + '"'
-
- def table_print(self, _mode, with_results):
- if self.expected is None:
- expected = ''
- else:
- expected = self.expected
- print('{:<40}|{:^7}|{:^12}|{:^10}|{:^18}'.format(self.name, self.type, expected, self.decision, self.reason), end='')
- if with_results:
- print('| {}'.format(self.result), end='')
-
- def json_dump(self, with_results):
- dump = [self.name, self.type, self.expected, self.decision, self.reason]
- if with_results:
- dump.append(self.result)
- return dump
-
-
-class KconfigCheck(OptCheck):
- def __init__(self, *args, **kwargs):
- super().__init__(*args, **kwargs)
- self.name = 'CONFIG_' + self.name
-
- @property
- def type(self):
- return 'kconfig'
-
-
-class CmdlineCheck(OptCheck):
- @property
- def type(self):
- return 'cmdline'
-
-
-class VersionCheck:
- def __init__(self, ver_expected):
- self.ver_expected = ver_expected
- self.ver = ()
- self.result = None
-
- @property
- def type(self):
- return 'version'
-
- def check(self):
- if self.ver[0] > self.ver_expected[0]:
- self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
- return
- if self.ver[0] < self.ver_expected[0]:
- self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
- return
- if self.ver[1] >= self.ver_expected[1]:
- self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
- return
- self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
-
- def table_print(self, _mode, with_results):
- ver_req = 'kernel version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
- print('{:<91}'.format(ver_req), end='')
- if with_results:
- print('| {}'.format(self.result), end='')
-
-
-class ComplexOptCheck:
- def __init__(self, *opts):
- self.opts = opts
- assert(self.opts), \
- 'empty {} check'.format(self.__class__.__name__)
- assert(len(self.opts) != 1), \
- 'useless {} check: {}'.format(self.__class__.__name__, opts)
- assert(isinstance(opts[0], (KconfigCheck, CmdlineCheck))), \
- 'invalid {} check: {}'.format(self.__class__.__name__, opts)
- self.result = None
-
- @property
- def type(self):
- return 'complex'
-
- @property
- def name(self):
- return self.opts[0].name
-
- @property
- def expected(self):
- return self.opts[0].expected
-
- def table_print(self, mode, with_results):
- if mode == 'verbose':
- print(' {:87}'.format('<<< ' + self.__class__.__name__ + ' >>>'), end='')
- if with_results:
- print('| {}'.format(self.result), end='')
- for o in self.opts:
- print()
- o.table_print(mode, with_results)
- else:
- o = self.opts[0]
- o.table_print(mode, False)
- if with_results:
- print('| {}'.format(self.result), end='')
-
- def json_dump(self, with_results):
- dump = self.opts[0].json_dump(False)
- if with_results:
- dump.append(self.result)
- return dump
-
-
-class OR(ComplexOptCheck):
- # self.opts[0] is the option that this OR-check is about.
- # Use cases:
- # OR(<X_is_hardened>, <X_is_disabled>)
- # OR(<X_is_hardened>, <old_X_is_hardened>)
- def check(self):
- for i, opt in enumerate(self.opts):
- opt.check()
- if opt.result.startswith('OK'):
- self.result = opt.result
- # Add more info for additional checks:
- if i != 0:
- if opt.result == 'OK':
- self.result = 'OK: {} "{}"'.format(opt.name, opt.expected)
- elif opt.result == 'OK: not found':
- self.result = 'OK: {} not found'.format(opt.name)
- elif opt.result == 'OK: is present':
- self.result = 'OK: {} is present'.format(opt.name)
- else:
- # VersionCheck provides enough info
- assert(opt.result.startswith('OK: version')), \
- 'unexpected OK description "{}"'.format(opt.result)
- return
- self.result = self.opts[0].result
-
-
-class AND(ComplexOptCheck):
- # self.opts[0] is the option that this AND-check is about.
- # Use cases:
- # AND(<suboption>, <main_option>)
- # Suboption is not checked if checking of the main_option is failed.
- # AND(<X_is_disabled>, <old_X_is_disabled>)
- def check(self):
- for i, opt in reversed(list(enumerate(self.opts))):
- opt.check()
- if i == 0:
- self.result = opt.result
- return
- if not opt.result.startswith('OK'):
- # This FAIL is caused by additional checks,
- # and not by the main option that this AND-check is about.
- # Describe the reason of the FAIL.
- if opt.result.startswith('FAIL: \"') or opt.result == 'FAIL: not found':
- self.result = 'FAIL: {} not "{}"'.format(opt.name, opt.expected)
- elif opt.result == 'FAIL: not present':
- self.result = 'FAIL: {} not present'.format(opt.name)
- else:
- # VersionCheck provides enough info
- self.result = opt.result
- assert(opt.result.startswith('FAIL: version')), \
- 'unexpected FAIL description "{}"'.format(opt.result)
- return
+ return open_method(file, *args, **kwargs)
def detect_arch(fname, archs):
- with open(fname, 'r') as f:
- arch_pattern = re.compile("CONFIG_[a-zA-Z0-9_]*=y")
+ with _open(fname, 'rt', encoding='utf-8') as f:
+ arch_pattern = re.compile("CONFIG_[a-zA-Z0-9_]+=y$")
arch = None
for line in f.readlines():
if arch_pattern.match(line):
option, _ = line[7:].split('=', 1)
if option in archs:
- if not arch:
+ if arch is None:
arch = option
else:
- return None, 'more than one supported architecture is detected'
- if not arch:
- return None, 'failed to detect architecture'
+ return None, 'detected more than one microarchitecture'
+ if arch is None:
+ return None, 'failed to detect microarchitecture'
return arch, 'OK'
def detect_kernel_version(fname):
- with open(fname, 'r') as f:
- ver_pattern = re.compile("# Linux/.* Kernel Configuration")
+ with _open(fname, 'rt', encoding='utf-8') as f:
+ ver_pattern = re.compile("# Linux/.+ Kernel Configuration$")
for line in f.readlines():
if ver_pattern.match(line):
line = line.strip()
ver_str = parts[2]
ver_numbers = ver_str.split('.')
if len(ver_numbers) < 3 or not ver_numbers[0].isdigit() or not ver_numbers[1].isdigit():
- msg = 'failed to parse the version "' + ver_str + '"'
+ msg = f'failed to parse the version "{ver_str}"'
return None, msg
return (int(ver_numbers[0]), int(ver_numbers[1])), None
return None, 'no kernel version detected'
def detect_compiler(fname):
gcc_version = None
clang_version = None
- with open(fname, 'r') as f:
+ with _open(fname, 'rt', encoding='utf-8') as f:
gcc_version_pattern = re.compile("CONFIG_GCC_VERSION=[0-9]*")
clang_version_pattern = re.compile("CONFIG_CLANG_VERSION=[0-9]*")
for line in f.readlines():
gcc_version = line[19:-1]
if clang_version_pattern.match(line):
clang_version = line[21:-1]
- if not gcc_version or not clang_version:
+ if gcc_version is None or clang_version is None:
return None, 'no CONFIG_GCC_VERSION or CONFIG_CLANG_VERSION'
if gcc_version == '0' and clang_version != '0':
return 'CLANG ' + clang_version, 'OK'
if gcc_version != '0' and clang_version == '0':
return 'GCC ' + gcc_version, 'OK'
- sys.exit('[!] ERROR: invalid GCC_VERSION and CLANG_VERSION: {} {}'.format(gcc_version, clang_version))
-
-
-def add_kconfig_checks(l, arch):
- # Calling the KconfigCheck class constructor:
- # KconfigCheck(reason, decision, name, expected)
- #
- # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
- # when the tool doesn't check the cmdline.
-
- efi_not_set = KconfigCheck('-', '-', 'EFI', 'is not set')
- cc_is_gcc = KconfigCheck('-', '-', 'CC_IS_GCC', 'y') # exists since v4.18
- cc_is_clang = KconfigCheck('-', '-', 'CC_IS_CLANG', 'y') # exists since v4.18
-
- modules_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'MODULES', 'is not set')
- devmem_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'DEVMEM', 'is not set') # refers to LOCKDOWN
- bpf_syscall_not_set = KconfigCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set') # refers to LOCKDOWN
-
- # 'self_protection', 'defconfig'
- l += [KconfigCheck('self_protection', 'defconfig', 'BUG', 'y')]
- l += [KconfigCheck('self_protection', 'defconfig', 'SLUB_DEBUG', 'y')]
- gcc_plugins_support_is_set = KconfigCheck('self_protection', 'defconfig', 'GCC_PLUGINS', 'y')
- l += [gcc_plugins_support_is_set]
- l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR', 'y'),
- KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR', 'y'),
- KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_REGULAR', 'y'),
- KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_AUTO', 'y'),
- KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
- l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_STRONG', 'y'),
- KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
- l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_KERNEL_RWX', 'y'),
- KconfigCheck('self_protection', 'defconfig', 'DEBUG_RODATA', 'y'))] # before v4.11
- l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_MODULE_RWX', 'y'),
- KconfigCheck('self_protection', 'defconfig', 'DEBUG_SET_MODULE_RONX', 'y'),
- modules_not_set)] # DEBUG_SET_MODULE_RONX was before v4.11
- l += [OR(KconfigCheck('self_protection', 'defconfig', 'REFCOUNT_FULL', 'y'),
- VersionCheck((5, 5)))] # REFCOUNT_FULL is enabled by default since v5.5
- l += [KconfigCheck('self_protection', 'defconfig', 'THREAD_INFO_IN_TASK', 'y')]
- iommu_support_is_set = KconfigCheck('self_protection', 'defconfig', 'IOMMU_SUPPORT', 'y')
- l += [iommu_support_is_set] # is needed for mitigating DMA attacks
- if arch in ('X86_64', 'ARM64', 'X86_32'):
- l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y')]
- if arch in ('X86_64', 'ARM64'):
- l += [KconfigCheck('self_protection', 'defconfig', 'VMAP_STACK', 'y')]
- if arch in ('X86_64', 'X86_32'):
- l += [KconfigCheck('self_protection', 'defconfig', 'MICROCODE', 'y')] # is needed for mitigating CPU bugs
- l += [KconfigCheck('self_protection', 'defconfig', 'RETPOLINE', 'y')]
- l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_SMAP', 'y'),
- VersionCheck((5, 19)))] # X86_SMAP is enabled by default since v5.19
- l += [KconfigCheck('self_protection', 'defconfig', 'SYN_COOKIES', 'y')] # another reason?
- l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_UMIP', 'y'),
- KconfigCheck('self_protection', 'defconfig', 'X86_INTEL_UMIP', 'y'))]
- if arch in ('ARM64', 'ARM'):
- l += [KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_PER_TASK', 'y')]
- if arch == 'X86_64':
- l += [KconfigCheck('self_protection', 'defconfig', 'PAGE_TABLE_ISOLATION', 'y')]
- l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MEMORY', 'y')]
- l += [AND(KconfigCheck('self_protection', 'defconfig', 'INTEL_IOMMU', 'y'),
- iommu_support_is_set)]
- l += [AND(KconfigCheck('self_protection', 'defconfig', 'AMD_IOMMU', 'y'),
- iommu_support_is_set)]
- if arch == 'ARM64':
- l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PAN', 'y')]
- l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_EPAN', 'y')]
- l += [KconfigCheck('self_protection', 'defconfig', 'UNMAP_KERNEL_AT_EL0', 'y')]
- l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_EL2_VECTORS', 'y'),
- AND(KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y'),
- VersionCheck((5, 9))))] # HARDEN_EL2_VECTORS was included in RANDOMIZE_BASE in v5.9
- l += [KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y')]
- l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PTR_AUTH_KERNEL', 'y')]
- l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_BTI_KERNEL', 'y')]
- l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y'),
- VersionCheck((5, 10)))] # HARDEN_BRANCH_PREDICTOR is enabled by default since v5.10
- l += [KconfigCheck('self_protection', 'defconfig', 'MITIGATE_SPECTRE_BRANCH_HISTORY', 'y')]
- l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_MTE', 'y')]
- l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MODULE_REGION_FULL', 'y')]
- if arch == 'ARM':
- l += [KconfigCheck('self_protection', 'defconfig', 'CPU_SW_DOMAIN_PAN', 'y')]
- l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y')]
- l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_HISTORY', 'y')]
-
- # 'self_protection', 'kspp'
- l += [KconfigCheck('self_protection', 'kspp', 'BUG_ON_DATA_CORRUPTION', 'y')]
- l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_WX', 'y')]
- l += [KconfigCheck('self_protection', 'kspp', 'SCHED_STACK_END_CHECK', 'y')]
- l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_HARDENED', 'y')]
- l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_RANDOM', 'y')]
- l += [KconfigCheck('self_protection', 'kspp', 'SHUFFLE_PAGE_ALLOCATOR', 'y')]
- l += [KconfigCheck('self_protection', 'kspp', 'FORTIFY_SOURCE', 'y')]
- l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_LIST', 'y')]
- l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_SG', 'y')]
- l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_CREDENTIALS', 'y')]
- l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_NOTIFIERS', 'y')]
- l += [KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y')]
- l += [AND(KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_LATENT_ENTROPY', 'y'),
- gcc_plugins_support_is_set)]
- l += [KconfigCheck('self_protection', 'kspp', 'KFENCE', 'y')]
- l += [KconfigCheck('self_protection', 'kspp', 'WERROR', 'y')]
- l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y')]
- l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set')] # true if IOMMU_DEFAULT_DMA_STRICT is set
- l += [KconfigCheck('self_protection', 'kspp', 'ZERO_CALL_USED_REGS', 'y')]
- randstruct_is_set = OR(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_FULL', 'y'),
- KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT', 'y'))
- l += [randstruct_is_set]
- hardened_usercopy_is_set = KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y')
- l += [hardened_usercopy_is_set]
- l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
- hardened_usercopy_is_set)]
- l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_PAGESPAN', 'is not set'),
- hardened_usercopy_is_set)]
- l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG', 'y'),
- modules_not_set)]
- l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_ALL', 'y'),
- modules_not_set)]
- l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_SHA512', 'y'),
- modules_not_set)]
- l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_FORCE', 'y'),
- modules_not_set)] # refers to LOCKDOWN
- l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_STACK_ALL_ZERO', 'y'),
- KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y'))]
- l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
- KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'))]
- # CONFIG_INIT_ON_FREE_DEFAULT_ON was added in v5.3.
- # CONFIG_PAGE_POISONING_ZERO was removed in v5.11.
- # Starting from v5.11 CONFIG_PAGE_POISONING unconditionally checks
- # the 0xAA poison pattern on allocation.
- # That brings higher performance penalty.
- if arch in ('X86_64', 'ARM64', 'X86_32'):
- stackleak_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STACKLEAK', 'y')
- l += [AND(stackleak_is_set, gcc_plugins_support_is_set)]
- l += [KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y')]
- if arch in ('X86_64', 'X86_32'):
- l += [KconfigCheck('self_protection', 'kspp', 'SCHED_CORE', 'y')]
- l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '65536')]
- if arch in ('ARM64', 'ARM'):
- l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '32768')]
- l += [KconfigCheck('self_protection', 'kspp', 'SYN_COOKIES', 'y')] # another reason?
- if arch == 'ARM64':
- l += [KconfigCheck('self_protection', 'kspp', 'ARM64_SW_TTBR0_PAN', 'y')]
- if arch == 'X86_32':
- l += [KconfigCheck('self_protection', 'kspp', 'PAGE_TABLE_ISOLATION', 'y')]
- l += [KconfigCheck('self_protection', 'kspp', 'HIGHMEM64G', 'y')]
- l += [KconfigCheck('self_protection', 'kspp', 'X86_PAE', 'y')]
-
- # 'self_protection', 'maintainer'
- ubsan_bounds_is_set = KconfigCheck('self_protection', 'maintainer', 'UBSAN_BOUNDS', 'y') # only array index bounds checking
- l += [ubsan_bounds_is_set] # recommended by Kees Cook in /issues/53
- if arch in ('X86_64', 'ARM64', 'X86_32'): # ARCH_HAS_UBSAN_SANITIZE_ALL is not enabled for ARM
- l += [AND(KconfigCheck('self_protection', 'maintainer', 'UBSAN_SANITIZE_ALL', 'y'),
- ubsan_bounds_is_set)] # recommended by Kees Cook in /issues/53
- l += [AND(KconfigCheck('self_protection', 'maintainer', 'UBSAN_TRAP', 'y'),
- ubsan_bounds_is_set)] # recommended by Kees Cook in /issues/53
-
- # 'self_protection', 'clipos'
- l += [KconfigCheck('self_protection', 'clipos', 'DEBUG_VIRTUAL', 'y')]
- l += [KconfigCheck('self_protection', 'clipos', 'STATIC_USERMODEHELPER', 'y')] # needs userspace support
- l += [OR(KconfigCheck('self_protection', 'clipos', 'EFI_DISABLE_PCI_DMA', 'y'),
- efi_not_set)]
- l += [KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set')]
- l += [KconfigCheck('self_protection', 'clipos', 'RANDOM_TRUST_BOOTLOADER', 'is not set')]
- l += [KconfigCheck('self_protection', 'clipos', 'RANDOM_TRUST_CPU', 'is not set')]
- l += [AND(KconfigCheck('self_protection', 'clipos', 'RANDSTRUCT_PERFORMANCE', 'is not set'),
- KconfigCheck('self_protection', 'clipos', 'GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set'),
- randstruct_is_set)]
- if arch in ('X86_64', 'ARM64', 'X86_32'):
- l += [AND(KconfigCheck('self_protection', 'clipos', 'STACKLEAK_METRICS', 'is not set'),
- stackleak_is_set,
- gcc_plugins_support_is_set)]
- l += [AND(KconfigCheck('self_protection', 'clipos', 'STACKLEAK_RUNTIME_DISABLE', 'is not set'),
- stackleak_is_set,
- gcc_plugins_support_is_set)]
- if arch in ('X86_64', 'X86_32'):
- l += [AND(KconfigCheck('self_protection', 'clipos', 'INTEL_IOMMU_DEFAULT_ON', 'y'),
- iommu_support_is_set)]
- if arch == 'X86_64':
- l += [AND(KconfigCheck('self_protection', 'clipos', 'INTEL_IOMMU_SVM', 'y'),
- iommu_support_is_set)]
- if arch == 'X86_32':
- l += [AND(KconfigCheck('self_protection', 'clipos', 'INTEL_IOMMU', 'y'),
- iommu_support_is_set)]
-
- # 'self_protection', 'my'
- l += [OR(KconfigCheck('self_protection', 'my', 'RESET_ATTACK_MITIGATION', 'y'),
- efi_not_set)] # needs userspace support (systemd)
- l += [OR(KconfigCheck('self_protection', 'my', 'UBSAN_LOCAL_BOUNDS', 'y'),
- AND(ubsan_bounds_is_set,
- cc_is_gcc))]
- if arch == 'X86_64':
- l += [KconfigCheck('self_protection', 'my', 'SLS', 'y')] # vs CVE-2021-26341 in Straight-Line-Speculation
- l += [AND(KconfigCheck('self_protection', 'my', 'AMD_IOMMU_V2', 'y'),
- iommu_support_is_set)]
- if arch == 'ARM64':
- l += [KconfigCheck('self_protection', 'my', 'SHADOW_CALL_STACK', 'y')] # maybe it's alternative to STACKPROTECTOR_STRONG
- l += [KconfigCheck('self_protection', 'my', 'KASAN_HW_TAGS', 'y')]
- cfi_clang_is_set = KconfigCheck('self_protection', 'my', 'CFI_CLANG', 'y')
- l += [cfi_clang_is_set]
- l += [AND(KconfigCheck('self_protection', 'my', 'CFI_PERMISSIVE', 'is not set'),
- cfi_clang_is_set)]
-
- # 'security_policy'
- if arch in ('X86_64', 'ARM64', 'X86_32'):
- l += [KconfigCheck('security_policy', 'defconfig', 'SECURITY', 'y')] # and choose your favourite LSM
- if arch == 'ARM':
- l += [KconfigCheck('security_policy', 'kspp', 'SECURITY', 'y')] # and choose your favourite LSM
- l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_YAMA', 'y')]
- l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LANDLOCK', 'y')]
- l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DISABLE', 'is not set')]
- l += [KconfigCheck('security_policy', 'clipos', 'SECURITY_LOCKDOWN_LSM', 'y')]
- l += [KconfigCheck('security_policy', 'clipos', 'SECURITY_LOCKDOWN_LSM_EARLY', 'y')]
- l += [KconfigCheck('security_policy', 'clipos', 'LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y')]
- l += [KconfigCheck('security_policy', 'my', 'SECURITY_WRITABLE_HOOKS', 'is not set')] # refers to SECURITY_SELINUX_DISABLE
- l += [KconfigCheck('security_policy', 'my', 'SECURITY_SAFESETID', 'y')]
- loadpin_is_set = KconfigCheck('security_policy', 'my', 'SECURITY_LOADPIN', 'y')
- l += [loadpin_is_set] # needs userspace support
- l += [AND(KconfigCheck('security_policy', 'my', 'SECURITY_LOADPIN_ENFORCE', 'y'),
- loadpin_is_set)]
-
- # 'cut_attack_surface', 'defconfig'
- l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'BPF_UNPRIV_DEFAULT_OFF', 'y'),
- bpf_syscall_not_set)] # see unprivileged_bpf_disabled
- l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP', 'y')]
- l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP_FILTER', 'y')]
- if arch in ('X86_64', 'ARM64', 'X86_32'):
- l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'STRICT_DEVMEM', 'y'),
- devmem_not_set)] # refers to LOCKDOWN
-
- # 'cut_attack_surface', 'kspp'
- l += [KconfigCheck('cut_attack_surface', 'kspp', 'SECURITY_DMESG_RESTRICT', 'y')]
- l += [KconfigCheck('cut_attack_surface', 'kspp', 'ACPI_CUSTOM_METHOD', 'is not set')] # refers to LOCKDOWN
- l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_BRK', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'kspp', 'DEVKMEM', 'is not set')] # refers to LOCKDOWN
- l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_VDSO', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'kspp', 'BINFMT_MISC', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'kspp', 'INET_DIAG', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'kspp', 'KEXEC', 'is not set')] # refers to LOCKDOWN
- l += [KconfigCheck('cut_attack_surface', 'kspp', 'PROC_KCORE', 'is not set')] # refers to LOCKDOWN
- l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_PTYS', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'kspp', 'HIBERNATION', 'is not set')] # refers to LOCKDOWN
- l += [KconfigCheck('cut_attack_surface', 'kspp', 'IA32_EMULATION', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_X32', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'kspp', 'MODIFY_LDT_SYSCALL', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'kspp', 'OABI_COMPAT', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_MSR', 'is not set')] # refers to LOCKDOWN
- l += [modules_not_set]
- l += [devmem_not_set]
- l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'IO_STRICT_DEVMEM', 'y'),
- devmem_not_set)] # refers to LOCKDOWN
- if arch == 'ARM':
- l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'STRICT_DEVMEM', 'y'),
- devmem_not_set)] # refers to LOCKDOWN
- if arch == 'X86_64':
- l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y')] # 'vsyscall=none'
-
- # 'cut_attack_surface', 'grsec'
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'ZSMALLOC_STAT', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'PAGE_OWNER', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_KMEMLEAK', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'BINFMT_AOUT', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'KPROBE_EVENTS', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'UPROBE_EVENTS', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'GENERIC_TRACER', 'is not set')] # refers to LOCKDOWN
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'FUNCTION_TRACER', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'STACK_TRACER', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'HIST_TRIGGERS', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'BLK_DEV_IO_TRACE', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_VMCORE', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_PAGE_MONITOR', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'USELIB', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'CHECKPOINT_RESTORE', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'USERFAULTFD', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'HWPOISON_INJECT', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'MEM_SOFT_DIRTY', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEVPORT', 'is not set')] # refers to LOCKDOWN
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set')] # refers to LOCKDOWN
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'NOTIFIER_ERROR_INJECTION', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'FAIL_FUTEX', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'PUNIT_ATOM_DEBUG', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'ACPI_CONFIGFS', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'EDAC_DEBUG', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'DRM_I915_DEBUG', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'BCACHE_CLOSURES_DEBUG', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'DVB_C8SECTPFE', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_SLRAM', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_PHRAM', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'IO_URING', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCMP', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'RSEQ', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'LATENCYTOP', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCOV', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROVIDE_OHCI1394_DMA_INIT', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'grsec', 'SUNRPC_DEBUG', 'is not set')]
- l += [AND(KconfigCheck('cut_attack_surface', 'grsec', 'PTDUMP_DEBUGFS', 'is not set'),
- KconfigCheck('cut_attack_surface', 'grsec', 'X86_PTDUMP', 'is not set'))]
-
- # 'cut_attack_surface', 'maintainer'
- l += [KconfigCheck('cut_attack_surface', 'maintainer', 'DRM_LEGACY', 'is not set')] # recommended by Daniel Vetter in /issues/38
- l += [KconfigCheck('cut_attack_surface', 'maintainer', 'FB', 'is not set')] # recommended by Daniel Vetter in /issues/38
- l += [KconfigCheck('cut_attack_surface', 'maintainer', 'VT', 'is not set')] # recommended by Daniel Vetter in /issues/38
- l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD', 'is not set')] # recommended by Denis Efremov in /pull/54
- l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD_RAWCMD', 'is not set')] # recommended by Denis Efremov in /pull/62
-
- # 'cut_attack_surface', 'grapheneos'
- l += [KconfigCheck('cut_attack_surface', 'grapheneos', 'AIO', 'is not set')]
-
- # 'cut_attack_surface', 'clipos'
- l += [KconfigCheck('cut_attack_surface', 'clipos', 'STAGING', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'clipos', 'KSM', 'is not set')] # to prevent FLUSH+RELOAD attack
-# l += [KconfigCheck('cut_attack_surface', 'clipos', 'IKCONFIG', 'is not set')] # no, IKCONFIG is needed for this check :)
- l += [KconfigCheck('cut_attack_surface', 'clipos', 'KALLSYMS', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_VSYSCALL_EMULATION', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'clipos', 'MAGIC_SYSRQ', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'clipos', 'KEXEC_FILE', 'is not set')] # refers to LOCKDOWN (permissive)
- l += [KconfigCheck('cut_attack_surface', 'clipos', 'USER_NS', 'is not set')] # user.max_user_namespaces=0
- l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_CPUID', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_IOPL_IOPERM', 'is not set')] # refers to LOCKDOWN
- l += [KconfigCheck('cut_attack_surface', 'clipos', 'ACPI_TABLE_UPGRADE', 'is not set')] # refers to LOCKDOWN
- l += [KconfigCheck('cut_attack_surface', 'clipos', 'EFI_CUSTOM_SSDT_OVERLAYS', 'is not set')]
- l += [AND(KconfigCheck('cut_attack_surface', 'clipos', 'LDISC_AUTOLOAD', 'is not set'),
- KconfigCheck('cut_attack_surface', 'clipos', 'LDISC_AUTOLOAD'))] # option presence check
- if arch in ('X86_64', 'X86_32'):
- l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_INTEL_TSX_MODE_OFF', 'y')] # tsx=off
-
- # 'cut_attack_surface', 'lockdown'
- l += [bpf_syscall_not_set] # refers to LOCKDOWN
- l += [KconfigCheck('cut_attack_surface', 'lockdown', 'EFI_TEST', 'is not set')] # refers to LOCKDOWN
- l += [KconfigCheck('cut_attack_surface', 'lockdown', 'MMIOTRACE_TEST', 'is not set')] # refers to LOCKDOWN
- l += [KconfigCheck('cut_attack_surface', 'lockdown', 'KPROBES', 'is not set')] # refers to LOCKDOWN
-
- # 'cut_attack_surface', 'my'
- l += [OR(KconfigCheck('cut_attack_surface', 'my', 'TRIM_UNUSED_KSYMS', 'y'),
- modules_not_set)]
- l += [KconfigCheck('cut_attack_surface', 'my', 'MMIOTRACE', 'is not set')] # refers to LOCKDOWN (permissive)
- l += [KconfigCheck('cut_attack_surface', 'my', 'LIVEPATCH', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'my', 'IP_DCCP', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'my', 'IP_SCTP', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'my', 'FTRACE', 'is not set')] # refers to LOCKDOWN
- l += [KconfigCheck('cut_attack_surface', 'my', 'VIDEO_VIVID', 'is not set')]
- l += [KconfigCheck('cut_attack_surface', 'my', 'INPUT_EVBUG', 'is not set')] # Can be used as a keylogger
- l += [KconfigCheck('cut_attack_surface', 'my', 'KGDB', 'is not set')]
-
- # 'harden_userspace'
- if arch in ('X86_64', 'ARM64', 'X86_32'):
- l += [KconfigCheck('harden_userspace', 'defconfig', 'INTEGRITY', 'y')]
- if arch == 'ARM':
- l += [KconfigCheck('harden_userspace', 'my', 'INTEGRITY', 'y')]
- if arch == 'ARM64':
- l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_PTR_AUTH', 'y')]
- l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_BTI', 'y')]
- if arch in ('ARM', 'X86_32'):
- l += [KconfigCheck('harden_userspace', 'defconfig', 'VMSPLIT_3G', 'y')]
- if arch in ('X86_64', 'ARM64'):
- l += [KconfigCheck('harden_userspace', 'clipos', 'ARCH_MMAP_RND_BITS', '32')]
- if arch in ('X86_32', 'ARM'):
- l += [KconfigCheck('harden_userspace', 'my', 'ARCH_MMAP_RND_BITS', '16')]
-
-
-def add_cmdline_checks(l, arch):
- # Calling the CmdlineCheck class constructor:
- # CmdlineCheck(reason, decision, name, expected)
- #
- # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
- # when the tool doesn't check the cmdline.
- #
- # [!] Make sure that values of the options in CmdlineChecks need normalization.
- # For more info see normalize_cmdline_options().
- #
- # A common pattern for checking the 'param_x' cmdline parameter
- # that __overrides__ the 'PARAM_X_DEFAULT' kconfig option:
- # l += [OR(CmdlineCheck(reason, decision, 'param_x', '1'),
- # AND(KconfigCheck(reason, decision, 'PARAM_X_DEFAULT_ON', 'y'),
- # CmdlineCheck(reason, decision, 'param_x, 'is not set')))]
- #
- # Here we don't check the kconfig options or minimal kernel version
- # required for the cmdline parameters. That would make the checks
- # very complex and not give a 100% guarantee anyway.
-
- # 'self_protection', 'defconfig'
- if arch == 'ARM64':
- l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', 'full'),
- AND(KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y'),
- CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set')))]
- else:
- l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', '1'),
- CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set'))]
-
- # 'self_protection', 'kspp'
- l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', '1'),
- AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y'),
- CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', 'is not set')))]
- l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_free', '1'),
- AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
- CmdlineCheck('self_protection', 'kspp', 'init_on_free', 'is not set')),
- AND(CmdlineCheck('self_protection', 'kspp', 'page_poison', '1'),
- KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'),
- CmdlineCheck('self_protection', 'kspp', 'slub_debug', 'P')))]
- l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_nomerge'),
- AND(KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set'),
- CmdlineCheck('self_protection', 'kspp', 'slab_merge', 'is not set')))] # option presence check
- l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.strict', '1'),
- AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y'),
- CmdlineCheck('self_protection', 'kspp', 'iommu.strict', 'is not set')))]
- l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', '0'),
- AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set'),
- CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', 'is not set')))]
- # The cmdline checks compatible with the kconfig recommendations of the KSPP project...
- l += [CmdlineCheck('self_protection', 'kspp', 'nokaslr', 'is not set')]
- l += [OR(CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', '1'),
- AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y'),
- CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', 'is not set')))]
- l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', '0'),
- AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
- CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', 'is not set')))]
- if arch in ('X86_64', 'X86_32'):
- l += [AND(CmdlineCheck('self_protection', 'kspp', 'pti', 'on'),
- CmdlineCheck('self_protection', 'kspp', 'nopti', 'is not set'))] # ... the end
- if arch in ('X86_64', 'ARM64', 'X86_32'):
- l += [OR(CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', '1'),
- AND(KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y'),
- CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', 'is not set')))]
-
- # 'self_protection', 'clipos'
- l += [CmdlineCheck('self_protection', 'clipos', 'page_alloc.shuffle', '1')]
-
- # 'self_protection', 'my'
- l += [CmdlineCheck('self_protection', 'my', 'nosmep', 'is not set')]
- l += [CmdlineCheck('self_protection', 'my', 'nosmap', 'is not set')]
-
- # 'cut_attack_surface', 'kspp'
- if arch == 'X86_64':
- l += [OR(CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'none'),
- AND(KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y'),
- CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'is not set')))]
-
- # 'cut_attack_surface', 'grsec'
- # The cmdline checks compatible with the kconfig options disabled by grsecurity...
- l += [OR(CmdlineCheck('cut_attack_surface', 'grsec', 'debugfs', 'off'),
- KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set'))] # ... the end
+ sys.exit(f'[!] ERROR: invalid GCC_VERSION and CLANG_VERSION: {gcc_version} {clang_version}')
def print_unknown_options(checklist, parsed_options):
continue
for o3 in o2.opts:
assert(o3.type != 'complex'), \
- 'unexpected ComplexOptCheck inside {}'.format(o2.name)
+ f'unexpected ComplexOptCheck inside {o2.name}'
if hasattr(o3, 'name'):
known_options.append(o3.name)
for option, value in parsed_options.items():
if option not in known_options:
- print('[?] No check for option {} ({})'.format(option, value))
+ print(f'[?] No check for option {option} ({value})')
def print_checklist(mode, checklist, with_results):
if mode == 'json':
output = []
- for o in checklist:
- output.append(o.json_dump(with_results))
+ for opt in checklist:
+ output.append(opt.json_dump(with_results))
print(json.dumps(output))
return
if with_results:
sep_line_len += 30
print('=' * sep_line_len)
- print('{:^40}|{:^7}|{:^12}|{:^10}|{:^18}'.format('option name', 'type', 'desired val', 'decision', 'reason'), end='')
+ print(f'{"option name":^40}|{"type":^7}|{"desired val":^12}|{"decision":^10}|{"reason":^18}', end='')
if with_results:
- print('| {}'.format('check result'), end='')
+ print('| check result', end='')
print()
print('=' * sep_line_len)
fail_suppressed = ' (suppressed in output)'
if mode == 'show_fail':
ok_suppressed = ' (suppressed in output)'
- if mode != 'json':
- print('[+] Config check is finished: \'OK\' - {}{} / \'FAIL\' - {}{}'.format(ok_count, ok_suppressed, fail_count, fail_suppressed))
-
-
-def populate_simple_opt_with_data(opt, data, data_type):
- assert(opt.type != 'complex'), \
- 'unexpected ComplexOptCheck "{}"'.format(opt.name)
- assert(opt.type in SIMPLE_OPTION_TYPES), \
- 'invalid opt type "{}"'.format(opt.type)
- assert(data_type in SIMPLE_OPTION_TYPES), \
- 'invalid data type "{}"'.format(data_type)
-
- if data_type != opt.type:
- return
-
- if data_type in ('kconfig', 'cmdline'):
- opt.state = data.get(opt.name, None)
- else:
- assert(data_type == 'version'), \
- 'unexpected data type "{}"'.format(data_type)
- opt.ver = data
-
-
-def populate_opt_with_data(opt, data, data_type):
- if opt.type == 'complex':
- for o in opt.opts:
- if o.type == 'complex':
- # Recursion for nested ComplexOptCheck objects
- populate_opt_with_data(o, data, data_type)
- else:
- populate_simple_opt_with_data(o, data, data_type)
- else:
- assert(opt.type in ('kconfig', 'cmdline')), \
- 'bad type "{}" for a simple check'.format(opt.type)
- populate_simple_opt_with_data(opt, data, data_type)
-
-
-def populate_with_data(checklist, data, data_type):
- for opt in checklist:
- populate_opt_with_data(opt, data, data_type)
-
-
-def perform_checks(checklist):
- for opt in checklist:
- opt.check()
+ print(f'[+] Config check is finished: \'OK\' - {ok_count}{ok_suppressed} / \'FAIL\' - {fail_count}{fail_suppressed}')
def parse_kconfig_file(parsed_options, fname):
- with open(fname, 'r') as f:
+ with _open(fname, 'rt', encoding='utf-8') as f:
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 opt_is_on.match(line):
option, value = line.split('=', 1)
if value == 'is not set':
- sys.exit('[!] ERROR: bad enabled kconfig option "{}"'.format(line))
+ sys.exit(f'[!] ERROR: bad enabled Kconfig option "{line}"')
elif opt_is_off.match(line):
option, value = line[2:].split(' ', 1)
if value != 'is not set':
- sys.exit('[!] ERROR: bad disabled kconfig option "{}"'.format(line))
+ sys.exit(f'[!] ERROR: bad disabled Kconfig option "{line}"')
if option in parsed_options:
- sys.exit('[!] ERROR: kconfig option "{}" exists multiple times'.format(line))
+ sys.exit(f'[!] ERROR: Kconfig option "{line}" exists multiple times')
if option:
parsed_options[option] = value
-def normalize_cmdline_options(option, value):
- # Don't normalize the cmdline option values if
- # the Linux kernel doesn't use kstrtobool() for them
- if option == 'pti':
- # See pti_check_boottime_disable() in linux/arch/x86/mm/pti.c
- return value
- if option == 'debugfs':
- # See debugfs_kernel() in fs/debugfs/inode.c
- return value
-
- # Implement a limited part of the kstrtobool() logic
- if value in ('1', 'on', 'On', 'ON', 'y', 'Y', 'yes', 'Yes', 'YES'):
- return '1'
- if value in ('0', 'off', 'Off', 'OFF', 'n', 'N', 'no', 'No', 'NO'):
- return '0'
-
- # Preserve unique values
- return value
-
-
def parse_cmdline_file(parsed_options, fname):
- with open(fname, 'r') as f:
+ with open(fname, 'r', encoding='utf-8') as f:
line = f.readline()
opts = line.split()
line = f.readline()
if line:
- sys.exit('[!] ERROR: more than one line in "{}"'.format(fname))
+ sys.exit(f'[!] ERROR: more than one line in "{fname}"')
for opt in opts:
if '=' in opt:
else:
name = opt
value = '' # '' is not None
+ if name in parsed_options:
+ sys.exit(f'[!] ERROR: cmdline option "{name}" exists multiple times')
value = normalize_cmdline_options(name, value)
parsed_options[name] = value
+def parse_sysctl_file(parsed_options, fname):
+ print('parse_sysctl_file: TODO')
+
+
def main():
# Report modes:
# * verbose mode for
- # - reporting about unknown kernel options in the kconfig
+ # - reporting about unknown kernel options in the Kconfig
# - verbose printing of ComplexOptCheck items
# * json mode for printing the results in JSON format
report_modes = ['verbose', 'json', 'show_ok', 'show_fail']
parser = ArgumentParser(prog='kconfig-hardened-check',
description='A tool for checking the security hardening options of the Linux kernel')
parser.add_argument('--version', action='version', version='%(prog)s ' + __version__)
- parser.add_argument('-p', '--print', choices=supported_archs,
- help='print security hardening preferences for the selected architecture')
- parser.add_argument('-c', '--config',
- help='check the kernel kconfig file against these preferences')
- parser.add_argument('-l', '--cmdline',
- help='check the kernel cmdline file against these preferences')
parser.add_argument('-m', '--mode', choices=report_modes,
help='choose the report mode')
+ parser.add_argument('-c', '--config',
+ help='check the security hardening options in the kernel Kconfig file (also supports *.gz files)')
+ parser.add_argument('-l', '--cmdline',
+ help='check the security hardening options in the kernel cmdline file (contents of /proc/cmdline)')
+# parser.add_argument('-s', '--sysctl',
+# help='check the security hardening options in the sysctl output file (`sudo sysctl -a > file`)')
+ parser.add_argument('-p', '--print', choices=supported_archs,
+ help='print the security hardening recommendations for the selected microarchitecture')
+ parser.add_argument('-g', '--generate', choices=supported_archs,
+ help='generate a Kconfig fragment with the security hardening options for the selected microarchitecture')
args = parser.parse_args()
+ args.sysctl = None # FIXME
mode = None
if args.mode:
mode = args.mode
if mode != 'json':
- print('[+] Special report mode: {}'.format(mode))
+ print(f'[+] Special report mode: {mode}')
config_checklist = []
if args.print:
sys.exit('[!] ERROR: --config and --print can\'t be used together')
+ if args.generate:
+ sys.exit('[!] ERROR: --config and --generate can\'t be used together')
+
if mode != 'json':
- print('[+] Kconfig file to check: {}'.format(args.config))
+ print(f'[+] Kconfig file to check: {args.config}')
if args.cmdline:
- print('[+] Kernel cmdline file to check: {}'.format(args.cmdline))
+ print(f'[+] Kernel cmdline file to check: {args.cmdline}')
+ if args.sysctl:
+ print(f'[+] Kernel sysctl output file to check: {args.sysctl}')
arch, msg = detect_arch(args.config, supported_archs)
- if not arch:
- sys.exit('[!] ERROR: {}'.format(msg))
+ if arch is None:
+ sys.exit(f'[!] ERROR: {msg}')
if mode != 'json':
- print('[+] Detected architecture: {}'.format(arch))
+ print(f'[+] Detected microarchitecture: {arch}')
kernel_version, msg = detect_kernel_version(args.config)
- if not kernel_version:
- sys.exit('[!] ERROR: {}'.format(msg))
+ if kernel_version is None:
+ sys.exit(f'[!] ERROR: {msg}')
if mode != 'json':
- print('[+] Detected kernel version: {}.{}'.format(kernel_version[0], kernel_version[1]))
+ print(f'[+] Detected kernel version: {kernel_version[0]}.{kernel_version[1]}')
compiler, msg = detect_compiler(args.config)
if mode != 'json':
if compiler:
- print('[+] Detected compiler: {}'.format(compiler))
+ print(f'[+] Detected compiler: {compiler}')
else:
- print('[-] Can\'t detect the compiler: {}'.format(msg))
+ print(f'[-] Can\'t detect the compiler: {msg}')
- # add relevant kconfig checks to the checklist
+ # add relevant Kconfig checks to the checklist
add_kconfig_checks(config_checklist, arch)
if args.cmdline:
# add relevant cmdline checks to the checklist
add_cmdline_checks(config_checklist, arch)
- # populate the checklist with the parsed kconfig data
+ if args.sysctl:
+ # add relevant sysctl checks to the checklist
+ add_sysctl_checks(config_checklist, arch)
+
+ # populate the checklist with the parsed Kconfig data
parsed_kconfig_options = OrderedDict()
parse_kconfig_file(parsed_kconfig_options, args.config)
populate_with_data(config_checklist, parsed_kconfig_options, 'kconfig')
+
+ # populate the checklist with the kernel version data
populate_with_data(config_checklist, kernel_version, 'version')
if args.cmdline:
- # populate the checklist with the parsed kconfig data
+ # populate the checklist with the parsed cmdline data
parsed_cmdline_options = OrderedDict()
parse_cmdline_file(parsed_cmdline_options, args.cmdline)
populate_with_data(config_checklist, parsed_cmdline_options, 'cmdline')
- # now everything is ready for performing the checks
+ if args.sysctl:
+ # populate the checklist with the parsed sysctl data
+ parsed_sysctl_options = OrderedDict()
+ parse_sysctl_file(parsed_sysctl_options, args.sysctl)
+ populate_with_data(config_checklist, parsed_sysctl_options, 'sysctl')
+
+ # hackish refinement of the CONFIG_ARCH_MMAP_RND_BITS check
+ mmap_rnd_bits_max = parsed_kconfig_options.get('CONFIG_ARCH_MMAP_RND_BITS_MAX', None)
+ if mmap_rnd_bits_max:
+ override_expected_value(config_checklist, 'CONFIG_ARCH_MMAP_RND_BITS', mmap_rnd_bits_max)
+
+ # now everything is ready, perform the checks
perform_checks(config_checklist)
- # finally print the results
if mode == 'verbose':
- print_unknown_options(config_checklist, parsed_kconfig_options)
+ # print the parsed options without the checks (for debugging)
+ all_parsed_options = parsed_kconfig_options # assignment does not copy
+ if args.cmdline:
+ all_parsed_options.update(parsed_cmdline_options)
+ if args.sysctl:
+ all_parsed_options.update(parsed_sysctl_options)
+ print_unknown_options(config_checklist, all_parsed_options)
+
+ # finally print the results
print_checklist(mode, config_checklist, True)
sys.exit(0)
elif args.cmdline:
- sys.exit('[!] ERROR: checking cmdline doesn\'t work without checking kconfig')
+ sys.exit('[!] ERROR: checking cmdline depends on checking Kconfig')
+ elif args.sysctl:
+ # TODO: sysctl check should also work separately
+ sys.exit('[!] ERROR: checking sysctl depends on checking Kconfig')
if args.print:
- if mode in ('show_ok', 'show_fail'):
- sys.exit('[!] ERROR: wrong mode "{}" for --print'.format(mode))
+ assert(args.config is None and args.cmdline is None and args.sysctl is None), 'unexpected args'
+ if mode and mode not in ('verbose', 'json'):
+ sys.exit(f'[!] ERROR: wrong mode "{mode}" for --print')
arch = args.print
add_kconfig_checks(config_checklist, arch)
add_cmdline_checks(config_checklist, arch)
+ add_sysctl_checks(config_checklist, arch)
if mode != 'json':
- print('[+] Printing kernel security hardening preferences for {}...'.format(arch))
+ print(f'[+] Printing kernel security hardening options for {arch}...')
print_checklist(mode, config_checklist, False)
sys.exit(0)
+ if args.generate:
+ assert(args.config is None and args.cmdline is None and args.sysctl is None), 'unexpected args'
+ if mode:
+ sys.exit(f'[!] ERROR: wrong mode "{mode}" for --generate')
+ arch = args.generate
+ add_kconfig_checks(config_checklist, arch)
+ print(f'CONFIG_{arch}=y') # the Kconfig fragment should describe the microarchitecture
+ for opt in config_checklist:
+ if opt.name == 'CONFIG_ARCH_MMAP_RND_BITS':
+ continue # don't add CONFIG_ARCH_MMAP_RND_BITS because its value needs refinement
+ if opt.expected == 'is not set':
+ print(f'# {opt.name} is not set')
+ else:
+ print(f'{opt.name}={opt.expected}')
+ sys.exit(0)
+
parser.print_help()
sys.exit(0)
projects / kconfig-hardened-check.git / blobdiff