X-Git-Url: https://jxself.org/git/?a=blobdiff_plain;f=kconfig_hardened_check%2F__init__.py;h=563091cd77abb9727e8b647fc59847bd1245bcaa;hb=361e571e1926ee172f22f9aad990158e2c03651d;hp=37bc1fb52a26b3ecea69a38d659de42e9e0635fa;hpb=271e6bf01d9f854a696bb0b547194d90690c35d5;p=kconfig-hardened-check.git diff --git a/kconfig_hardened_check/__init__.py b/kconfig_hardened_check/__init__.py index 37bc1fb..563091c 100644 --- a/kconfig_hardened_check/__init__.py +++ b/kconfig_hardened_check/__init__.py @@ -11,18 +11,18 @@ # # # N.B Hardening command line parameters: -# slub_debug=FZP # slab_nomerge # page_alloc.shuffle=1 # iommu=force (does it help against DMA attacks?) -# page_poison=1 (if enabled) -# init_on_alloc=1 -# init_on_free=1 +# slub_debug=FZ (slow) +# init_on_alloc=1 (since v5.3) +# init_on_free=1 (since v5.3, otherwise slub_debug=P and page_poison=1) # loadpin.enforce=1 +# debugfs=no-mount (or off if possible) # # Mitigations of CPU vulnerabilities: # Аrch-independent: -# mitigations=auto,nosmt +# mitigations=auto,nosmt (nosmt is slow) # X86: # spectre_v2=on # pti=on @@ -41,6 +41,7 @@ # 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 # @@ -54,6 +55,11 @@ # fs.suid_dumpable=0 # kernel.modules_disabled=1 + +# pylint: disable=missing-module-docstring,missing-class-docstring,missing-function-docstring +# pylint: disable=line-too-long,invalid-name,too-many-branches,too-many-statements + + import sys from argparse import ArgumentParser from collections import OrderedDict @@ -61,18 +67,6 @@ import re import json from .__about__ import __version__ -# pylint: disable=line-too-long,bad-whitespace,too-many-branches -# pylint: disable=too-many-statements,global-statement - -# Report modes: -# * verbose mode for -# - reporting about unknown kernel options in the config -# - verbose printing of ComplexOptCheck items -# * json mode for printing the results in JSON format -report_modes = ['verbose', 'json'] - -supported_archs = ['X86_64', 'X86_32', 'ARM64', 'ARM'] - class OptCheck: def __init__(self, reason, decision, name, expected): @@ -98,7 +92,7 @@ class OptCheck: return True return False - def table_print(self, mode, with_results): + def table_print(self, _mode, with_results): print('CONFIG_{:<38}|{:^13}|{:^10}|{:^20}'.format(self.name, self.expected, self.decision, self.reason), end='') if with_results: print('| {}'.format(self.result), end='') @@ -107,7 +101,7 @@ class OptCheck: class VerCheck: def __init__(self, ver_expected): self.ver_expected = ver_expected - self.ver = None + self.ver = () self.result = None def check(self): @@ -123,7 +117,7 @@ class VerCheck: self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1]) return False - def table_print(self, mode, with_results): + 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: @@ -143,7 +137,7 @@ class PresenceCheck: self.result = 'OK: is present' return True - def table_print(self, mode, with_results): + def table_print(self, _mode, with_results): print('CONFIG_{:<84}'.format(self.name + ' is present'), end='') if with_results: print('| {}'.format(self.result), end='') @@ -152,6 +146,10 @@ class PresenceCheck: class ComplexOptCheck: def __init__(self, *opts): self.opts = opts + if not self.opts: + sys.exit('[!] ERROR: empty {} check'.format(self.__class__.__name__)) + if not isinstance(opts[0], OptCheck): + sys.exit('[!] ERROR: invalid {} check: {}'.format(self.__class__.__name__, opts)) self.result = None @property @@ -187,9 +185,9 @@ class ComplexOptCheck: class OR(ComplexOptCheck): # self.opts[0] is the option that this OR-check is about. - # Use case: + # Use cases: # OR(, ) - # OR(, ) + # OR(, ) def check(self): if not self.opts: @@ -198,9 +196,13 @@ class OR(ComplexOptCheck): for i, opt in enumerate(self.opts): ret = opt.check() if ret: - if i == 0 or not hasattr(opt, 'expected'): + if opt.result != 'OK' or i == 0: + # Preserve additional explanation of this OK result. + # Simple OK is enough only for the main option that + # this OR-check is about. self.result = opt.result else: + # Simple OK is not enough for additional checks. self.result = 'OK: CONFIG_{} "{}"'.format(opt.name, opt.expected) return True self.result = self.opts[0].result @@ -209,8 +211,10 @@ class OR(ComplexOptCheck): class AND(ComplexOptCheck): # self.opts[0] is the option that this AND-check is about. - # Use case: AND(, ) - # Suboption is not checked if checking of the main_option is failed. + # Use cases: + # AND(, ) + # Suboption is not checked if checking of the main_option is failed. + # AND(, ) def check(self): for i, opt in reversed(list(enumerate(self.opts))): @@ -219,23 +223,29 @@ class AND(ComplexOptCheck): self.result = opt.result return ret if not ret: - if hasattr(opt, 'expected'): - self.result = 'FAIL: CONFIG_{} is needed'.format(opt.name) + # 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: CONFIG_{} not "{}"'.format(opt.name, opt.expected) + elif opt.result == 'FAIL: not present': + self.result = 'FAIL: CONFIG_{} not present'.format(opt.name) else: + # This FAIL message is self-explaining. self.result = opt.result return False sys.exit('[!] ERROR: invalid AND check') -def detect_arch(fname): +def detect_arch(fname, archs): with open(fname, 'r') 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 supported_archs: + if option in archs: if not arch: arch = option else: @@ -297,9 +307,12 @@ def construct_checklist(l, arch): if arch == 'ARM64': l += [OptCheck('self_protection', 'defconfig', 'ARM64_PAN', 'y')] l += [OptCheck('self_protection', 'defconfig', 'UNMAP_KERNEL_AT_EL0', 'y')] - l += [OptCheck('self_protection', 'defconfig', 'HARDEN_EL2_VECTORS', 'y')] + l += [OR(OptCheck('self_protection', 'defconfig', 'HARDEN_EL2_VECTORS', 'y'), + AND(OptCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y'), + VerCheck((5, 9))))] # HARDEN_EL2_VECTORS was included in RANDOMIZE_BASE in v5.9 l += [OptCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y')] l += [OptCheck('self_protection', 'defconfig', 'ARM64_PTR_AUTH', 'y')] + l += [OptCheck('self_protection', 'defconfig', 'ARM64_BTI_KERNEL', 'y')] if arch in ('X86_64', 'ARM64'): l += [OptCheck('self_protection', 'defconfig', 'VMAP_STACK', 'y')] if arch in ('X86_64', 'ARM64', 'X86_32'): @@ -308,7 +321,10 @@ def construct_checklist(l, arch): if arch == 'ARM': l += [OptCheck('self_protection', 'defconfig', 'CPU_SW_DOMAIN_PAN', 'y')] l += [OptCheck('self_protection', 'defconfig', 'STACKPROTECTOR_PER_TASK', 'y')] - if arch in ('ARM64', 'ARM'): + if arch == 'ARM64': + l += [OR(OptCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y'), + VerCheck((5, 10)))] # HARDEN_BRANCH_PREDICTOR is enabled by default since v5.10 + if arch == 'ARM': l += [OptCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y')] # 'self_protection', 'kspp' @@ -339,10 +355,10 @@ def construct_checklist(l, arch): modules_not_set)] l += [OR(OptCheck('self_protection', 'kspp', 'MODULE_SIG_FORCE', 'y'), modules_not_set)] # refers to LOCKDOWN - l += [OR(OptCheck('self_protection', 'kspp', 'INIT_STACK_ALL', 'y'), + l += [OR(OptCheck('self_protection', 'kspp', 'INIT_STACK_ALL_ZERO', 'y'), OptCheck('self_protection', 'kspp', 'GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y'))] l += [OR(OptCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'), - OptCheck('self_protection', 'kspp', 'PAGE_POISONING', 'y'))] # before v5.3 + OptCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'))] # before v5.3 if arch in ('X86_64', 'ARM64', 'X86_32'): stackleak_is_set = OptCheck('self_protection', 'kspp', 'GCC_PLUGIN_STACKLEAK', 'y') l += [stackleak_is_set] @@ -362,6 +378,7 @@ def construct_checklist(l, arch): l += [OptCheck('self_protection', 'clipos', 'SECURITY_DMESG_RESTRICT', 'y')] l += [OptCheck('self_protection', 'clipos', 'DEBUG_VIRTUAL', 'y')] l += [OptCheck('self_protection', 'clipos', 'STATIC_USERMODEHELPER', 'y')] # needs userspace support + l += [OptCheck('self_protection', 'clipos', 'EFI_DISABLE_PCI_DMA', 'y')] l += [OptCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set')] # slab_nomerge l += [OptCheck('self_protection', 'clipos', 'RANDOM_TRUST_BOOTLOADER', 'is not set')] l += [OptCheck('self_protection', 'clipos', 'RANDOM_TRUST_CPU', 'is not set')] @@ -382,11 +399,15 @@ def construct_checklist(l, arch): iommu_support_is_set)] # 'self_protection', 'my' - l += [OptCheck('self_protection', 'my', 'SLUB_DEBUG_ON', 'y')] + l += [AND(OptCheck('self_protection', 'my', 'UBSAN_BOUNDS', 'y'), + OptCheck('self_protection', 'my', 'UBSAN_MISC', 'is not set'), + OptCheck('self_protection', 'my', 'UBSAN_TRAP', 'y'))] l += [OptCheck('self_protection', 'my', 'RESET_ATTACK_MITIGATION', 'y')] # needs userspace support (systemd) if arch == 'X86_64': l += [AND(OptCheck('self_protection', 'my', 'AMD_IOMMU_V2', 'y'), iommu_support_is_set)] + if arch == 'ARM64': + l += [OptCheck('self_protection', 'my', 'SHADOW_CALL_STACK', 'y')] # maybe it should be alternative to STACKPROTECTOR_STRONG # 'security_policy' if arch in ('X86_64', 'ARM64', 'X86_32'): @@ -438,7 +459,6 @@ def construct_checklist(l, arch): l += [OptCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y')] # 'vsyscall=none' # 'cut_attack_surface', 'grsecurity' - l += [OptCheck('cut_attack_surface', 'grsecurity', 'X86_PTDUMP', 'is not set')] l += [OptCheck('cut_attack_surface', 'grsecurity', 'ZSMALLOC_STAT', 'is not set')] l += [OptCheck('cut_attack_surface', 'grsecurity', 'PAGE_OWNER', 'is not set')] l += [OptCheck('cut_attack_surface', 'grsecurity', 'DEBUG_KMEMLEAK', 'is not set')] @@ -455,19 +475,17 @@ def construct_checklist(l, arch): l += [OptCheck('cut_attack_surface', 'grsecurity', 'MEM_SOFT_DIRTY', 'is not set')] l += [OptCheck('cut_attack_surface', 'grsecurity', 'DEVPORT', 'is not set')] # refers to LOCKDOWN l += [OptCheck('cut_attack_surface', 'grsecurity', 'DEBUG_FS', 'is not set')] # refers to LOCKDOWN - l += [OptCheck('cut_attack_surface', 'grsecurity', 'NOTIFIER_ERROR_INJECTION','is not set')] + l += [OptCheck('cut_attack_surface', 'grsecurity', 'NOTIFIER_ERROR_INJECTION', 'is not set')] + l += [AND(OptCheck('cut_attack_surface', 'grsecurity', 'X86_PTDUMP', 'is not set'), + OptCheck('cut_attack_surface', 'my', 'PTDUMP_DEBUGFS', 'is not set'))] # 'cut_attack_surface', 'maintainer' l += [OptCheck('cut_attack_surface', 'maintainer', 'DRM_LEGACY', 'is not set')] l += [OptCheck('cut_attack_surface', 'maintainer', 'FB', 'is not set')] l += [OptCheck('cut_attack_surface', 'maintainer', 'VT', 'is not set')] - # 'cut_attack_surface', 'lockdown' - l += [OptCheck('cut_attack_surface', 'lockdown', 'ACPI_TABLE_UPGRADE', 'is not set')] # refers to LOCKDOWN - l += [OptCheck('cut_attack_surface', 'lockdown', 'X86_IOPL_IOPERM', 'is not set')] # refers to LOCKDOWN - l += [OptCheck('cut_attack_surface', 'lockdown', 'EFI_TEST', 'is not set')] # refers to LOCKDOWN - l += [OptCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set')] # refers to LOCKDOWN - l += [OptCheck('cut_attack_surface', 'lockdown', 'MMIOTRACE_TEST', 'is not set')] # refers to LOCKDOWN + # 'cut_attack_surface', 'grapheneos' + l += [OptCheck('cut_attack_surface', 'grapheneos', 'AIO', 'is not set')] # 'cut_attack_surface', 'clipos' l += [OptCheck('cut_attack_surface', 'clipos', 'STAGING', 'is not set')] @@ -480,26 +498,37 @@ def construct_checklist(l, arch): l += [OptCheck('cut_attack_surface', 'clipos', 'USER_NS', 'is not set')] # user.max_user_namespaces=0 l += [OptCheck('cut_attack_surface', 'clipos', 'X86_MSR', 'is not set')] # refers to LOCKDOWN l += [OptCheck('cut_attack_surface', 'clipos', 'X86_CPUID', 'is not set')] + l += [OptCheck('cut_attack_surface', 'clipos', 'IO_URING', 'is not set')] + l += [OptCheck('cut_attack_surface', 'clipos', 'X86_IOPL_IOPERM', 'is not set')] # refers to LOCKDOWN + l += [OptCheck('cut_attack_surface', 'clipos', 'ACPI_TABLE_UPGRADE', 'is not set')] # refers to LOCKDOWN + l += [OptCheck('cut_attack_surface', 'clipos', 'EFI_CUSTOM_SSDT_OVERLAYS', 'is not set')] l += [AND(OptCheck('cut_attack_surface', 'clipos', 'LDISC_AUTOLOAD', 'is not set'), PresenceCheck('LDISC_AUTOLOAD'))] if arch in ('X86_64', 'X86_32'): l += [OptCheck('cut_attack_surface', 'clipos', 'X86_INTEL_TSX_MODE_OFF', 'y')] # tsx=off - # 'cut_attack_surface', 'grapheneos' - l += [OptCheck('cut_attack_surface', 'grapheneos', 'AIO', 'is not set')] + # 'cut_attack_surface', 'lockdown' + l += [OptCheck('cut_attack_surface', 'lockdown', 'EFI_TEST', 'is not set')] # refers to LOCKDOWN + l += [OptCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set')] # refers to LOCKDOWN + l += [OptCheck('cut_attack_surface', 'lockdown', 'MMIOTRACE_TEST', 'is not set')] # refers to LOCKDOWN # 'cut_attack_surface', 'my' + l += [OptCheck('cut_attack_surface', 'my', 'TRIM_UNUSED_KSYMS', 'y')] l += [OptCheck('cut_attack_surface', 'my', 'MMIOTRACE', 'is not set')] # refers to LOCKDOWN (permissive) l += [OptCheck('cut_attack_surface', 'my', 'LIVEPATCH', 'is not set')] l += [OptCheck('cut_attack_surface', 'my', 'IP_DCCP', 'is not set')] l += [OptCheck('cut_attack_surface', 'my', 'IP_SCTP', 'is not set')] l += [OptCheck('cut_attack_surface', 'my', 'FTRACE', 'is not set')] # refers to LOCKDOWN - l += [OptCheck('cut_attack_surface', 'my', 'BPF_JIT', 'is not set')] l += [OptCheck('cut_attack_surface', 'my', 'VIDEO_VIVID', 'is not set')] l += [OptCheck('cut_attack_surface', 'my', 'INPUT_EVBUG', 'is not set')] # Can be used as a keylogger # 'userspace_hardening' - l += [OptCheck('userspace_hardening', 'defconfig', 'INTEGRITY', 'y')] + if arch in ('X86_64', 'ARM64', 'X86_32'): + l += [OptCheck('userspace_hardening', 'defconfig', 'INTEGRITY', 'y')] + if arch == 'ARM': + l += [OptCheck('userspace_hardening', 'my', 'INTEGRITY', 'y')] + if arch == 'ARM64': + l += [OptCheck('userspace_hardening', 'defconfig', 'ARM64_MTE', 'y')] if arch in ('ARM', 'X86_32'): l += [OptCheck('userspace_hardening', 'defconfig', 'VMSPLIT_3G', 'y')] if arch in ('X86_64', 'ARM64'): @@ -548,6 +577,13 @@ def print_checklist(mode, checklist, with_results): # table contents for opt in checklist: + if with_results: + if mode == 'show_ok': + if not opt.result.startswith('OK'): + continue + if mode == 'show_fail': + if not opt.result.startswith('FAIL'): + continue opt.table_print(mode, with_results) print() if mode == 'verbose': @@ -556,27 +592,40 @@ def print_checklist(mode, checklist, with_results): # final score if with_results: - error_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), checklist))) + fail_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), checklist))) + fail_suppressed = '' ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), checklist))) + ok_suppressed = '' + if mode == 'show_ok': + 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, error_count)) + print('[+] Config check is finished: \'OK\' - {}{} / \'FAIL\' - {}{}'.format(ok_count, ok_suppressed, fail_count, fail_suppressed)) + + +def perform_check(opt, parsed_options, kernel_version): + if hasattr(opt, 'opts'): + # prepare ComplexOptCheck + for o in opt.opts: + if hasattr(o, 'opts'): + # Recursion for nested ComplexOptChecks + perform_check(o, parsed_options, kernel_version) + if hasattr(o, 'state'): + o.state = parsed_options.get(o.name, None) + if hasattr(o, 'ver'): + o.ver = kernel_version + else: + # prepare simple check, opt.state is mandatory + if not hasattr(opt, 'state'): + sys.exit('[!] ERROR: bad simple check {}'.format(vars(opt))) + opt.state = parsed_options.get(opt.name, None) + opt.check() def perform_checks(checklist, parsed_options, kernel_version): for opt in checklist: - if hasattr(opt, 'opts'): - # prepare ComplexOptCheck - for o in opt.opts: - if hasattr(o, 'state'): - o.state = parsed_options.get(o.name, None) - if hasattr(o, 'ver'): - o.ver = kernel_version - else: - # prepare simple check - if not hasattr(opt, 'state'): - sys.exit('[!] ERROR: bad simple check {}'.format(vars(opt))) - opt.state = parsed_options.get(opt.name, None) - opt.check() + perform_check(opt, parsed_options, kernel_version) def parse_config_file(parsed_options, fname): @@ -606,33 +655,37 @@ def parse_config_file(parsed_options, fname): def main(): - mode = None - arch = None - kernel_version = None - config_checklist = [] - parsed_options = OrderedDict() - + # Report modes: + # * verbose mode for + # - reporting about unknown kernel options in the config + # - verbose printing of ComplexOptCheck items + # * json mode for printing the results in JSON format + report_modes = ['verbose', 'json', 'show_ok', 'show_fail'] + supported_archs = ['X86_64', 'X86_32', 'ARM64', 'ARM'] parser = ArgumentParser(prog='kconfig-hardened-check', description='Checks the hardening options in the Linux kernel config') parser.add_argument('--version', action='version', version='%(prog)s ' + __version__) 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') + help='check the kernel config file against these preferences') parser.add_argument('-m', '--mode', choices=report_modes, help='choose the report mode') args = parser.parse_args() + mode = None if args.mode: mode = args.mode if mode != 'json': print("[+] Special report mode: {}".format(mode)) + config_checklist = [] + if args.config: if mode != 'json': print('[+] Config file to check: {}'.format(args.config)) - arch, msg = detect_arch(args.config) + arch, msg = detect_arch(args.config, supported_archs) if not arch: sys.exit('[!] ERROR: {}'.format(msg)) if mode != 'json': @@ -645,6 +698,7 @@ def main(): print('[+] Detected kernel version: {}.{}'.format(kernel_version[0], kernel_version[1])) construct_checklist(config_checklist, arch) + parsed_options = OrderedDict() parse_config_file(parsed_options, args.config) perform_checks(config_checklist, parsed_options, kernel_version) @@ -655,6 +709,8 @@ def main(): sys.exit(0) if args.print: + if mode in ('show_ok', 'show_fail'): + sys.exit('[!] ERROR: please use "{}" mode for checking the kernel config'.format(mode)) arch = args.print construct_checklist(config_checklist, arch) if mode != 'json':