#
#
# N.B Hardening command line parameters:
-# page_alloc.shuffle=1
# iommu=force (does it help against DMA attacks?)
-# slub_debug=FZ (slow)
-# loadpin.enforce=1
-# debugfs=no-mount (or off if possible)
#
# 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)
# ssbd=force-on
#
# Should NOT be set:
-# nokaslr
# sysrq_always_enabled
# arm64.nobti
# arm64.nopauth
# 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
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)
+ def __init__(self, reason, decision, name, expected):
+ assert(name and name == name.strip() and len(name.split()) == 1), \
+ 'invalid name "{}" for {}'.format(name, self.__class__.__name__)
self.name = name
- self.expected = expected
+
+ assert(decision and decision == decision.strip() and len(decision.split()) == 1), \
+ 'invalid decision "{}" for "{}" check'.format(decision, name)
self.decision = decision
+
+ assert(reason and reason == reason.strip() and len(reason.split()) == 1), \
+ 'invalid reason "{}" for "{}" check'.format(reason, name)
self.reason = reason
+
+ assert(expected and expected == expected.strip()), \
+ 'invalid expected value "{}" for "{}" check (1)'.format(expected, name)
+ val_len = len(expected.split())
+ if val_len == 3:
+ assert(expected == 'is not set' or expected == 'is not off'), \
+ 'invalid expected value "{}" for "{}" check (2)'.format(expected, name)
+ elif val_len == 2:
+ assert(expected == 'is present'), \
+ 'invalid expected value "{}" for "{}" check (3)'.format(expected, name)
+ else:
+ assert(val_len == 1), \
+ 'invalid expected value "{}" for "{}" check (4)'.format(expected, name)
+ self.expected = expected
+
self.state = None
self.result = None
return None
def check(self):
- # handle the option presence check
- if self.expected is None:
+ # handle the 'is present' check
+ if self.expected == 'is present':
if self.state is None:
- self.result = 'FAIL: not present'
+ self.result = 'FAIL: is not present'
else:
self.result = 'OK: is present'
return
+ # handle the 'is not off' option check
+ if self.expected == 'is not off':
+ if self.state == 'off':
+ self.result = 'FAIL: is off'
+ elif self.state is None:
+ self.result = 'FAIL: is off, not found'
+ else:
+ self.result = 'OK: is not off, "' + self.state + '"'
+ 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'
+ self.result = 'OK: is not found'
else:
- self.result = 'FAIL: not found'
+ self.result = 'FAIL: is 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='')
+ print('{:<40}|{:^7}|{:^12}|{:^10}|{:^18}'.format(self.name, self.type, self.expected, self.decision, self.reason), end='')
if with_results:
print('| {}'.format(self.result), end='')
class VersionCheck:
def __init__(self, ver_expected):
+ assert(ver_expected and isinstance(ver_expected, tuple) and len(ver_expected) == 2), \
+ 'invalid version "{}" for VersionCheck'.format(ver_expected)
self.ver_expected = ver_expected
self.ver = ()
self.result = None
# 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)
+ self.result = 'OK: {} is "{}"'.format(opt.name, opt.expected)
+ elif opt.result == 'OK: is not found':
+ self.result = 'OK: {} is not found'.format(opt.name)
elif opt.result == 'OK: is present':
self.result = 'OK: {} is present'.format(opt.name)
+ elif opt.result.startswith('OK: is not off'):
+ self.result = 'OK: {} is not off'.format(opt.name)
else:
# VersionCheck provides enough info
assert(opt.result.startswith('OK: version')), \
# 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)
+ if opt.result.startswith('FAIL: \"') or opt.result == 'FAIL: is not found':
+ self.result = 'FAIL: {} is not "{}"'.format(opt.name, opt.expected)
+ elif opt.result == 'FAIL: is not present':
+ self.result = 'FAIL: {} is not present'.format(opt.name)
+ elif opt.result == 'FAIL: is off':
+ self.result = 'FAIL: {} is off'.format(opt.name)
+ elif opt.result == 'FAIL: is off, not found':
+ self.result = 'FAIL: {} is off, not found'.format(opt.name)
else:
# VersionCheck provides enough info
self.result = opt.result
return arch, 'OK'
-def detect_version(fname):
+def detect_kernel_version(fname):
with open(fname, 'r') as f:
ver_pattern = re.compile("# Linux/.* Kernel Configuration")
for line in f.readlines():
return None, 'no kernel version detected'
+def detect_compiler(fname):
+ gcc_version = None
+ clang_version = None
+ with open(fname, 'r') 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():
+ if gcc_version_pattern.match(line):
+ gcc_version = line[19:-1]
+ if clang_version_pattern.match(line):
+ clang_version = line[21:-1]
+ if not gcc_version or not clang_version:
+ 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
- efi_not_set = KconfigCheck('cut_attack_surface', 'my', 'EFI', 'is not set')
# 'self_protection', 'defconfig'
l += [KconfigCheck('self_protection', 'defconfig', 'BUG', 'y')]
l += [KconfigCheck('self_protection', 'defconfig', 'SLUB_DEBUG', 'y')]
- l += [KconfigCheck('self_protection', 'defconfig', 'GCC_PLUGINS', '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'),
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', 'X86_MCE', 'y')]
+ l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE_INTEL', 'y')]
+ l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE_AMD', 'y')]
l += [KconfigCheck('self_protection', 'defconfig', 'MICROCODE', 'y')] # is needed for mitigating CPU bugs
l += [KconfigCheck('self_protection', 'defconfig', 'RETPOLINE', 'y')]
- l += [KconfigCheck('self_protection', 'defconfig', 'X86_SMAP', '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'))]
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 += [KconfigCheck('self_protection', 'defconfig', 'ARM64_E0PD', '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', 'HARDEN_BRANCH_HISTORY', 'y')]
# 'self_protection', 'kspp'
- l += [KconfigCheck('self_protection', 'kspp', 'SECURITY_DMESG_RESTRICT', 'y')]
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', '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_VIRTUAL', '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 += [KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_LATENT_ENTROPY', '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 = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT', 'y')
+ l += [KconfigCheck('self_protection', 'kspp', 'HW_RANDOM_TPM', 'y')]
+ l += [KconfigCheck('self_protection', 'kspp', 'STATIC_USERMODEHELPER', 'y')] # needs userspace support
+ l += [KconfigCheck('self_protection', 'kspp', 'SCHED_CORE', 'y')]
+ randstruct_is_set = OR(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_FULL', 'y'),
+ KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT', 'y'))
l += [randstruct_is_set]
+ l += [AND(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_PERFORMANCE', 'is not set'),
+ KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set'),
+ 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'),
# Starting from v5.11 CONFIG_PAGE_POISONING unconditionally checks
# the 0xAA poison pattern on allocation.
# That brings higher performance penalty.
+ l += [OR(KconfigCheck('self_protection', 'kspp', 'EFI_DISABLE_PCI_DMA', 'y'),
+ efi_not_set)]
+ l += [OR(KconfigCheck('self_protection', 'kspp', 'RESET_ATTACK_MITIGATION', 'y'),
+ efi_not_set)] # needs userspace support (systemd)
+ ubsan_bounds_is_set = KconfigCheck('self_protection', 'kspp', 'UBSAN_BOUNDS', 'y')
+ l += [ubsan_bounds_is_set]
+ l += [OR(KconfigCheck('self_protection', 'kspp', 'UBSAN_LOCAL_BOUNDS', 'y'),
+ AND(ubsan_bounds_is_set,
+ cc_is_gcc))]
+ l += [AND(KconfigCheck('self_protection', 'kspp', 'UBSAN_TRAP', 'y'),
+ ubsan_bounds_is_set,
+ KconfigCheck('self_protection', 'kspp', 'UBSAN_SHIFT', 'is not set'),
+ KconfigCheck('self_protection', 'kspp', 'UBSAN_DIV_ZERO', 'is not set'),
+ KconfigCheck('self_protection', 'kspp', 'UBSAN_UNREACHABLE', 'is not set'),
+ KconfigCheck('self_protection', 'kspp', 'UBSAN_BOOL', 'is not set'),
+ KconfigCheck('self_protection', 'kspp', 'UBSAN_ENUM', 'is not set'),
+ KconfigCheck('self_protection', 'kspp', 'UBSAN_ALIGNMENT', 'is not set'))] # only array index bounds checking with traps
if arch in ('X86_64', 'ARM64', 'X86_32'):
+ l += [AND(KconfigCheck('self_protection', 'kspp', 'UBSAN_SANITIZE_ALL', 'y'),
+ ubsan_bounds_is_set)] # ARCH_HAS_UBSAN_SANITIZE_ALL is not enabled for ARM
stackleak_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STACKLEAK', 'y')
- l += [stackleak_is_set]
+ l += [AND(stackleak_is_set, gcc_plugins_support_is_set)]
+ l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_METRICS', 'is not set'),
+ stackleak_is_set,
+ gcc_plugins_support_is_set)]
+ l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_RUNTIME_DISABLE', 'is not set'),
+ stackleak_is_set,
+ gcc_plugins_support_is_set)]
l += [KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y')]
+ if arch in ('X86_64', 'ARM64'):
+ cfi_clang_is_set = KconfigCheck('self_protection', 'kspp', 'CFI_CLANG', 'y')
+ l += [cfi_clang_is_set]
+ l += [AND(KconfigCheck('self_protection', 'kspp', 'CFI_PERMISSIVE', 'is not set'),
+ cfi_clang_is_set)]
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')]
+ l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU_DEFAULT_ON', 'y'),
+ iommu_support_is_set)]
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 == 'X86_64':
+ l += [KconfigCheck('self_protection', 'kspp', 'SLS', 'y')] # vs CVE-2021-26341 in Straight-Line-Speculation
+ l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU_SVM', 'y'),
+ iommu_support_is_set)]
+ l += [AND(KconfigCheck('self_protection', 'kspp', 'AMD_IOMMU_V2', 'y'),
+ iommu_support_is_set)]
if arch == 'ARM64':
l += [KconfigCheck('self_protection', 'kspp', 'ARM64_SW_TTBR0_PAN', 'y')]
+ l += [KconfigCheck('self_protection', 'kspp', 'SHADOW_CALL_STACK', 'y')]
+ l += [KconfigCheck('self_protection', 'kspp', 'KASAN_HW_TAGS', '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
+ l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU', 'y'),
+ iommu_support_is_set)]
# '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', '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)]
- l += [AND(KconfigCheck('self_protection', 'clipos', 'STACKLEAK_RUNTIME_DISABLE', 'is not set'),
- stackleak_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)
- 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')] # depends on clang, 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'):
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)]
+ l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_BOOTPARAM', 'is not set')]
+ l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DEVELOP', 'is not set')]
+ l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LOCKDOWN_LSM', 'y')]
+ l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LOCKDOWN_LSM_EARLY', 'y')]
+ l += [KconfigCheck('security_policy', 'kspp', 'LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y')]
+ l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_WRITABLE_HOOKS', 'is not set')] # refers to SECURITY_SELINUX_DISABLE
# 'cut_attack_surface', 'defconfig'
l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'BPF_UNPRIV_DEFAULT_OFF', '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 += [devmem_not_set]
l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'IO_STRICT_DEVMEM', 'y'),
devmem_not_set)] # refers to LOCKDOWN
+ l += [AND(KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD', 'is not set'),
+ KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD', 'is present'))]
if arch == 'ARM':
l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'STRICT_DEVMEM', 'y'),
devmem_not_set)] # refers to LOCKDOWN
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
+ l += [KconfigCheck('cut_attack_surface', 'clipos', 'COREDUMP', 'is not set')] # cut userspace attack surface
if arch in ('X86_64', 'X86_32'):
l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_INTEL_TSX_MODE_OFF', 'y')] # tsx=off
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.
+ #
+ # [!] 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'
+ l += [CmdlineCheck('self_protection', 'defconfig', 'nosmep', 'is not set')]
+ l += [CmdlineCheck('self_protection', 'defconfig', 'nosmap', 'is not set')]
+ l += [CmdlineCheck('self_protection', 'defconfig', 'nokaslr', 'is not set')]
+ l += [CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set')]
+ l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v1', 'is not set')]
+ l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v2', 'is not set')]
+ l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not off'),
+ CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not set'))]
+ l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spectre_v2', 'is not off'),
+ CmdlineCheck('self_protection', 'defconfig', 'spectre_v2', 'is not set'))]
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 += [CmdlineCheck('self_protection', 'kspp', 'nosmt', 'is present')]
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')))]
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'),
+ l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_nomerge', 'is present'),
AND(KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set'),
- CmdlineCheck('self_protection', 'kspp', 'slab_merge', 'is not set')))] # option presence check
+ CmdlineCheck('self_protection', 'kspp', 'slab_merge', 'is not set')))]
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 += [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'),
- KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'))]
+ AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
+ CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', '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')))]
if arch in ('X86_64', 'X86_32'):
- l += [CmdlineCheck('self_protection', 'kspp', 'pti', 'on')]
+ l += [AND(CmdlineCheck('self_protection', 'kspp', 'pti', 'on'),
+ CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set'))]
+
+ # 'self_protection', 'clipos'
+ l += [CmdlineCheck('self_protection', 'clipos', 'page_alloc.shuffle', '1')]
+ # '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')))]
- # TODO: add other
+ # '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
def print_unknown_options(checklist, parsed_options):
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 == 'spectre_v2':
+ # See spectre_v2_parse_cmdline() in linux/arch/x86/kernel/cpu/bugs.c
+ return value
+ if option == 'debugfs':
+ # See debugfs_kernel() in fs/debugfs/inode.c
+ return value
+ if option == 'mitigations':
+ # See mitigations_parse_cmdline() in linux/kernel/cpu.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:
line = f.readline()
else:
name = opt
value = '' # '' is not None
+ value = normalize_cmdline_options(name, value)
parsed_options[name] = value
if mode != 'json':
print('[+] Detected architecture: {}'.format(arch))
- kernel_version, msg = detect_version(args.config)
+ kernel_version, msg = detect_kernel_version(args.config)
if not kernel_version:
sys.exit('[!] ERROR: {}'.format(msg))
if mode != 'json':
print('[+] Detected kernel version: {}.{}'.format(kernel_version[0], kernel_version[1]))
+ compiler, msg = detect_compiler(args.config)
+ if mode != 'json':
+ if compiler:
+ print('[+] Detected compiler: {}'.format(compiler))
+ else:
+ print('[-] Can\'t detect the compiler: {}'.format(msg))
+
# add relevant kconfig checks to the checklist
add_kconfig_checks(config_checklist, arch)
projects / kconfig-hardened-check.git / blobdiff