#!/usr/bin/env python3

"""
This tool is for checking the security hardening options of the Linux kernel.

SPDX-FileCopyrightText: Alexander Popov <alex.popov@linux.com>
SPDX-License-Identifier: GPL-3.0-only

This module contains knowledge for checks.
"""

# pylint: disable=missing-function-docstring,line-too-long
# pylint: disable=too-many-branches,too-many-statements,too-many-locals

from typing import List
from .engine import StrOrNone, ChecklistObjType, KconfigCheck, CmdlineCheck, SysctlCheck, VersionCheck, OR, AND


def add_kconfig_checks(l: List[ChecklistObjType], arch: str) -> None:
    assert(arch), 'empty 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
    if arch in ('X86_64', 'X86_32'):
        cpu_sup_amd_not_set = KconfigCheck('-', '-', 'CPU_SUP_AMD', 'is not set')
        cpu_sup_intel_not_set = KconfigCheck('-', '-', 'CPU_SUP_INTEL', 'is not set')

    modules_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'MODULES', 'is not set') # radical, but may be useful in some cases
    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')]
    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
    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, 4, 208)))]
             # REFCOUNT_FULL is enabled by default since v5.5,
             # and this is backported to v5.4.208
    l += [OR(KconfigCheck('self_protection', 'defconfig', 'INIT_STACK_ALL_ZERO', 'y'),
             AND(KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STRUCTLEAK', 'y'),
                 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y')))]
    l += [OR(KconfigCheck('self_protection', 'defconfig', 'CPU_MITIGATIONS', 'y'),
             KconfigCheck('self_protection', 'defconfig', 'SPECULATION_MITIGATIONS', 'y'))]
    if arch in ('X86_64', 'ARM64', 'X86_32'):
        l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y')]
    vmap_stack_is_set = KconfigCheck('self_protection', 'defconfig', 'VMAP_STACK', 'y')
    if arch in ('X86_64', 'ARM64', 'ARM'):
        l += [vmap_stack_is_set]
    if arch in ('X86_64', 'X86_32'):
        l += [KconfigCheck('self_protection', 'defconfig', 'DEBUG_WX', 'y')]
        l += [KconfigCheck('self_protection', 'defconfig', 'WERROR', 'y')]
        l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE', 'y')]
        l += [KconfigCheck('self_protection', 'defconfig', 'SYN_COOKIES', 'y')] # another reason?
        microcode_is_set = KconfigCheck('self_protection', 'defconfig', 'MICROCODE', 'y')
        l += [microcode_is_set] # is needed for mitigating CPU bugs
        l += [OR(KconfigCheck('self_protection', 'defconfig', 'MICROCODE_INTEL', 'y'),
                 cpu_sup_intel_not_set,
                 AND(microcode_is_set,
                     VersionCheck((6, 6, 0))))] # MICROCODE_INTEL was included in MICROCODE since v6.6
        l += [OR(KconfigCheck('self_protection', 'defconfig', 'MICROCODE_AMD', 'y'),
                 cpu_sup_amd_not_set,
                 AND(microcode_is_set,
                     VersionCheck((6, 6, 0))))] # MICROCODE_AMD was included in MICROCODE since v6.6
        l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_SMAP', 'y'),
                 VersionCheck((5, 19, 0)))] # X86_SMAP is enabled by default since v5.19
        l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_UMIP', 'y'),
                 KconfigCheck('self_protection', 'defconfig', 'X86_INTEL_UMIP', 'y'))]
        l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_MCE_INTEL', 'y'),
                 cpu_sup_intel_not_set)]
        l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_MCE_AMD', 'y'),
                 cpu_sup_amd_not_set)]
        l += [OR(KconfigCheck('self_protection', 'defconfig', 'MITIGATION_RETPOLINE', 'y'),
                 KconfigCheck('self_protection', 'defconfig', 'RETPOLINE', 'y'))]
        l += [OR(KconfigCheck('self_protection', 'defconfig', 'MITIGATION_RFDS', 'y'),
                 cpu_sup_intel_not_set)]
        l += [OR(KconfigCheck('self_protection', 'defconfig', 'MITIGATION_SPECTRE_BHI', 'y'),
                 cpu_sup_intel_not_set)]
    if arch in ('ARM64', 'ARM'):
        l += [KconfigCheck('self_protection', 'defconfig', 'HW_RANDOM_TPM', 'y')]
        l += [KconfigCheck('self_protection', 'defconfig', 'IOMMU_DEFAULT_DMA_STRICT', 'y')]
        l += [KconfigCheck('self_protection', 'defconfig', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set')] # true if IOMMU_DEFAULT_DMA_STRICT is set
        l += [KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_PER_TASK', 'y')]
    if arch == 'X86_64':
        l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MEMORY', 'y')]
        l += [KconfigCheck('self_protection', 'defconfig', 'X86_KERNEL_IBT', 'y')]
        l += [OR(KconfigCheck('self_protection', 'defconfig', 'MITIGATION_PAGE_TABLE_ISOLATION', 'y'),
                 KconfigCheck('self_protection', 'defconfig', 'PAGE_TABLE_ISOLATION', 'y'))]
        l += [OR(KconfigCheck('self_protection', 'defconfig', 'MITIGATION_SRSO', 'y'),
                 KconfigCheck('self_protection', 'defconfig', 'CPU_SRSO', 'y'),
                 cpu_sup_amd_not_set)]
        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 += [KconfigCheck('self_protection', 'defconfig', 'ARM64_E0PD', 'y')]
        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 += [KconfigCheck('self_protection', 'defconfig', 'ARM_SMMU', 'y')]
        l += [KconfigCheck('self_protection', 'defconfig', 'ARM_SMMU_DISABLE_BYPASS_BY_DEFAULT', 'y')]
        l += [KconfigCheck('self_protection', 'defconfig', 'ARM_SMMU_V3', 'y')]
        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')]
        l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_EL2_VECTORS', 'y'),
                 AND(KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y'),
                     VersionCheck((5, 9, 0))))] # HARDEN_EL2_VECTORS was included in RANDOMIZE_BASE in v5.9
        l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y'),
                 VersionCheck((5, 10, 0)))] # HARDEN_BRANCH_PREDICTOR is enabled by default since v5.10
    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')]
        l += [KconfigCheck('self_protection', 'defconfig', 'DEBUG_ALIGN_RODATA', 'y')]

    # 'self_protection', 'kspp'
    l += [KconfigCheck('self_protection', 'kspp', 'LIST_HARDENED', 'y')]
    l += [KconfigCheck('self_protection', 'kspp', 'RANDOM_KMALLOC_CACHES', 'y')]
    l += [KconfigCheck('self_protection', 'kspp', 'SLAB_MERGE_DEFAULT', 'is not set')]
    l += [KconfigCheck('self_protection', 'kspp', 'BUG_ON_DATA_CORRUPTION', '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_VIRTUAL', 'y')]
    l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_SG', 'y')]
    l += [KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y')]
    l += [KconfigCheck('self_protection', 'kspp', 'STATIC_USERMODEHELPER', 'y')] # needs userspace support
    l += [KconfigCheck('self_protection', 'kspp', 'SCHED_CORE', 'y')]
    l += [KconfigCheck('self_protection', 'kspp', 'SECURITY_LOCKDOWN_LSM', 'y')]
    l += [KconfigCheck('self_protection', 'kspp', 'SECURITY_LOCKDOWN_LSM_EARLY', 'y')]
    l += [KconfigCheck('self_protection', 'kspp', 'LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y')]
    cfi_clang_is_set = KconfigCheck('self_protection', 'kspp', 'CFI_CLANG', 'y')
    cfi_clang_permissive_not_set = KconfigCheck('self_protection', 'kspp', 'CFI_PERMISSIVE', 'is not set')
    l += [OR(KconfigCheck('self_protection', 'kspp', 'DEBUG_CREDENTIALS', 'y'),
             VersionCheck((6, 6, 8)))] # DEBUG_CREDENTIALS was dropped in v6.6.8
    l += [OR(KconfigCheck('self_protection', 'kspp', 'DEBUG_NOTIFIERS', 'y'),
             AND(cfi_clang_is_set,
                 cfi_clang_permissive_not_set,
                 cc_is_clang))]
    l += [OR(KconfigCheck('self_protection', 'kspp', 'SCHED_STACK_END_CHECK', 'y'),
             vmap_stack_is_set)]
    kfence_is_set = KconfigCheck('self_protection', 'kspp', 'KFENCE', 'y')
    l += [kfence_is_set]
    l += [AND(KconfigCheck('self_protection', 'kspp', 'KFENCE_SAMPLE_INTERVAL', '100'),
              kfence_is_set)]
    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)] # Comment this out for now: KSPP has revoked this recommendation
    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)] # usercopy whitelist violations should be prohibited
    l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_PAGESPAN', 'is not set'),
              hardened_usercopy_is_set)] # this debugging for HARDENED_USERCOPY is not needed for security
    l += [AND(KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_LATENT_ENTROPY', 'y'),
              cc_is_gcc)]
    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'),
             KconfigCheck('self_protection', 'a13xp0p0v', 'MODULE_SIG_SHA3_512', '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_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.
    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_SIGNED_WRAP', '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
    l += [OR(KconfigCheck('self_protection', 'kspp', 'UBSAN_SANITIZE_ALL', 'y'),
             AND(ubsan_bounds_is_set,
                 VersionCheck((6, 9, 0))))] # UBSAN_SANITIZE_ALL was enabled by default in UBSAN in v6.9
    if arch in ('X86_64', 'ARM64', 'X86_32'):
        stackleak_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STACKLEAK', 'y')
        l += [AND(stackleak_is_set,
                  cc_is_gcc)]
        l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_METRICS', 'is not set'),
                  stackleak_is_set,
                  cc_is_gcc)]
        l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_RUNTIME_DISABLE', 'is not set'),
                  stackleak_is_set,
                  cc_is_gcc)]
        l += [KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y')]
    if arch in ('X86_64', 'ARM64'):
        l += [KconfigCheck('self_protection', 'kspp', 'PAGE_TABLE_CHECK', 'y')]
        l += [KconfigCheck('self_protection', 'kspp', 'PAGE_TABLE_CHECK_ENFORCED', 'y')]
        l += [AND(cfi_clang_is_set,
                  cc_is_clang)]
        l += [AND(cfi_clang_permissive_not_set,
                  cfi_clang_is_set,
                  cc_is_clang)]
    if arch in ('X86_64', 'X86_32'):
        l += [KconfigCheck('self_protection', 'kspp', 'HW_RANDOM_TPM', 'y')]
        l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '65536')]
        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 += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU_DEFAULT_ON', 'y'),
                  iommu_support_is_set)]
    if arch in ('ARM64', 'ARM'):
        l += [KconfigCheck('self_protection', 'kspp', 'WERROR', 'y')]
        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 += [OR(KconfigCheck('self_protection', 'kspp', 'MITIGATION_SLS', 'y'),
                 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 += [OR(KconfigCheck('self_protection', 'kspp', 'AMD_IOMMU_V2', 'y'),
                 VersionCheck((6, 7, 0)))] # AMD_IOMMU_V2 was dropped in v6.7
    if arch == 'ARM64':
        l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_WX', 'y')]
        l += [KconfigCheck('self_protection', 'kspp', 'ARM64_SW_TTBR0_PAN', 'y')]
        l += [KconfigCheck('self_protection', 'kspp', 'SHADOW_CALL_STACK', 'y')]
        l += [KconfigCheck('self_protection', 'kspp', 'UNWIND_PATCH_PAC_INTO_SCS', 'y')]
        l += [KconfigCheck('self_protection', 'kspp', 'KASAN_HW_TAGS', 'y')] # see also: kasan=on, kasan.stacktrace=off, kasan.fault=panic
    if arch == 'X86_32':
        l += [KconfigCheck('self_protection', 'kspp', 'HIGHMEM64G', 'y')]
        l += [KconfigCheck('self_protection', 'kspp', 'X86_PAE', 'y')]
        l += [OR(KconfigCheck('self_protection', 'kspp', 'MITIGATION_PAGE_TABLE_ISOLATION', 'y'),
                 KconfigCheck('self_protection', 'kspp', 'PAGE_TABLE_ISOLATION', 'y'))]
        l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU', 'y'),
                  iommu_support_is_set)]
    if arch == 'ARM':
        l += [OR(KconfigCheck('self_protection', 'kspp', 'ARM_DEBUG_WX', 'y'),
                 KconfigCheck('self_protection', 'kspp', 'DEBUG_WX', 'y'))]
                 # DEBUG_WX has been renamed to ARM_DEBUG_WX on ARM

    # 'self_protection', 'a13xp0p0v'
    if arch == 'ARM':
        l += [KconfigCheck('self_protection', 'a13xp0p0v', 'ARM_SMMU', 'y')]
        l += [KconfigCheck('self_protection', 'a13xp0p0v', 'ARM_SMMU_DISABLE_BYPASS_BY_DEFAULT', 'y')]

    # 'security_policy'
    if arch in ('X86_64', 'ARM64', 'X86_32'):
        l += [KconfigCheck('security_policy', 'defconfig', 'SECURITY', 'y')]
    if arch == 'ARM':
        l += [KconfigCheck('security_policy', 'kspp', 'SECURITY', 'y')]
    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', 'kspp', 'SECURITY_SELINUX_BOOTPARAM', 'is not set')]
    l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DEVELOP', 'is not set')]
    l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_WRITABLE_HOOKS', 'is not set')] # refers to SECURITY_SELINUX_DISABLE
    l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DEBUG', 'is not set')]
    l += [OR(KconfigCheck('security_policy', 'a13xp0p0v', 'SECURITY_SELINUX', 'y'),
             KconfigCheck('security_policy', 'a13xp0p0v', 'SECURITY_APPARMOR', 'y'),
             KconfigCheck('security_policy', 'a13xp0p0v', 'SECURITY_SMACK', 'y'),
             KconfigCheck('security_policy', 'a13xp0p0v', 'SECURITY_TOMOYO', 'y'))] # one of major LSMs implementing MAC

    # N.B. We don't use 'if arch' for the 'cut_attack_surface' checks that require 'is not set'.
    # It makes the maintainance easier. These kernel options should be disabled anyway.
    # 'cut_attack_surface', 'defconfig'
    l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP', 'y')]
    l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP_FILTER', 'y')]
    l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'BPF_UNPRIV_DEFAULT_OFF', 'y'),
             bpf_syscall_not_set)] # see unprivileged_bpf_disabled
    if arch in ('X86_64', 'ARM64', 'X86_32'):
        l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'STRICT_DEVMEM', 'y'),
                 devmem_not_set)] # refers to LOCKDOWN
    if arch in ('X86_64', 'X86_32'):
        l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'X86_INTEL_TSX_MODE_OFF', 'y'),
                 cpu_sup_intel_not_set)] # tsx=off

    # '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', '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', 'COMPAT', 'is not set')]
    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', 'X86_X32_ABI', '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 += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_TIOCSTI', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'kspp', 'MODULE_FORCE_LOAD', 'is not set')]
    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
    l += [AND(KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD', 'is not set'),
              KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD', 'is present'))]
    l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'X86_VSYSCALL_EMULATION', 'is not set'),
             KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y'))]
             # disabling X86_VSYSCALL_EMULATION turns vsyscall off completely,
             # and LEGACY_VSYSCALL_NONE can be changed at boot time via the cmdline parameter
    if arch in ('X86_64', 'X86_32'):
        l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_VDSO', 'is not set')]
              # CONFIG_COMPAT_VDSO disabled ASLR of vDSO only on X86_64 and X86_32;
              # on ARM64 this option has different meaning
    if arch == 'ARM':
        l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'STRICT_DEVMEM', 'y'),
                 devmem_not_set)] # refers to LOCKDOWN

    # '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
    l += [KconfigCheck('cut_attack_surface', 'maintainer', 'NOUVEAU_LEGACY_CTX_SUPPORT', 'is not set')]
                                            # recommended by Dave Airlie in kernel commit b30a43ac7132cdda
    l += [KconfigCheck('cut_attack_surface', 'maintainer', 'N_GSM', 'is not set')]
                                            # recommended by Greg KH at https://www.openwall.com/lists/oss-security/2024/04/17/1

    # 'cut_attack_surface', 'grsec'
    l += [KconfigCheck('cut_attack_surface', 'grsec', 'ZSMALLOC_STAT', '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', '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 += [KconfigCheck('cut_attack_surface', 'grsec', 'X86_16BIT', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'grsec', 'BLK_DEV_UBLK', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'grsec', 'SMB_SERVER', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'grsec', 'XFS_ONLINE_SCRUB_STATS', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'grsec', 'CACHESTAT_SYSCALL', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'grsec', 'PREEMPTIRQ_TRACEPOINTS', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'grsec', 'ENABLE_DEFAULT_TRACERS', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROVE_LOCKING', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'grsec', 'TEST_DEBUG_VIRTUAL', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'grsec', 'MPTCP', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'grsec', 'TLS', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'grsec', 'TIPC', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'grsec', 'IP_SCTP', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'grsec', 'KGDB', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'grsec', 'PTDUMP_DEBUGFS', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'grsec', 'X86_PTDUMP', 'is not set')] # the old name of PTDUMP_DEBUGFS
    l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_CLOSURES', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'grsec', 'BCACHE_CLOSURES_DEBUG', 'is not set')] # the old name of DEBUG_CLOSURES

    # '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', 'KALLSYMS', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'clipos', 'KEXEC_FILE', 'is not set')] # refers to LOCKDOWN (permissive)
    l += [KconfigCheck('cut_attack_surface', 'clipos', 'CRASH_DUMP', 'is not set')]
    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 += [KconfigCheck('cut_attack_surface', 'clipos', 'AIO', 'is not set')]
#   l += [KconfigCheck('cut_attack_surface', 'clipos', 'IKCONFIG', 'is not set')] # no, IKCONFIG is needed for this check :)
    l += [OR(KconfigCheck('cut_attack_surface', 'clipos', 'MAGIC_SYSRQ', 'is not set'),
             KconfigCheck('cut_attack_surface', 'grapheneos', 'MAGIC_SYSRQ_DEFAULT_ENABLE', '0x0'))]

    # 'cut_attack_surface', 'grapheneos'
    l += [OR(KconfigCheck('cut_attack_surface', 'grapheneos', 'MAGIC_SYSRQ_SERIAL', 'is not set'),
             KconfigCheck('cut_attack_surface', 'grapheneos', 'MAGIC_SYSRQ_DEFAULT_ENABLE', '0x0'))]

    # 'cut_attack_surface', '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
    l += [bpf_syscall_not_set] # refers to LOCKDOWN

    # 'cut_attack_surface', 'a13xp0p0v'
    l += [KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'MMIOTRACE', 'is not set')] # refers to LOCKDOWN (permissive)
    l += [KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'LIVEPATCH', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'IP_DCCP', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'FTRACE', 'is not set')] # refers to LOCKDOWN
    l += [KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'VIDEO_VIVID', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'INPUT_EVBUG', 'is not set')] # Can be used as a keylogger
    l += [KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'CORESIGHT', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'XFS_SUPPORT_V4', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'BLK_DEV_WRITE_MOUNTED', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'FAULT_INJECTION', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'ARM_PTDUMP_DEBUGFS', 'is not set')]
    l += [KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'ARM_PTDUMP', 'is not set')] # the old name of ARM_PTDUMP_DEBUGFS
    l += [KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'LKDTM', 'is not set')]
                                            # dangerous, only for debugging the kernel hardening features!
    l += [OR(KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'TRIM_UNUSED_KSYMS', 'y'),
             modules_not_set)]

    # 'harden_userspace'
    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')]
    l += [KconfigCheck('harden_userspace', 'clipos', 'COREDUMP', 'is not set')]
    l += [KconfigCheck('harden_userspace', 'a13xp0p0v', 'ARCH_MMAP_RND_BITS', 'MAX')] # 'MAX' value is refined using ARCH_MMAP_RND_BITS_MAX
    if arch == 'X86_64':
        l += [KconfigCheck('harden_userspace', 'kspp', 'X86_USER_SHADOW_STACK', 'y')]


def add_cmdline_checks(l: List[ChecklistObjType], arch: str) -> None:
    assert(arch), 'empty 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'
    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 += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_bhb', 'is not set')]
    l += [CmdlineCheck('self_protection', 'defconfig', 'nospec_store_bypass_disable', 'is not set')]
    l += [CmdlineCheck('self_protection', 'defconfig', 'dis_ucode_ldr', 'is not set')]
    l += [CmdlineCheck('self_protection', 'defconfig', 'arm64.nobti', 'is not set')]
    l += [CmdlineCheck('self_protection', 'defconfig', 'arm64.nopauth', 'is not set')]
    l += [CmdlineCheck('self_protection', 'defconfig', 'arm64.nomte', 'is not set')]
    if arch in ('X86_64', 'X86_32'):
        l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spectre_v2', 'is not off'),
                 AND(CmdlineCheck('self_protection', 'kspp', 'mitigations', 'auto,nosmt'),
                     CmdlineCheck('self_protection', 'defconfig', 'spectre_v2', 'is not set')))]
        l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spectre_v2_user', 'is not off'),
                 AND(CmdlineCheck('self_protection', 'kspp', 'mitigations', 'auto,nosmt'),
                     CmdlineCheck('self_protection', 'defconfig', 'spectre_v2_user', 'is not set')))]
        l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spectre_bhi', 'is not off'),
                 AND(KconfigCheck('self_protection', 'defconfig', 'MITIGATION_SPECTRE_BHI', 'y'),
                     CmdlineCheck('self_protection', 'kspp', 'mitigations', 'auto,nosmt'),
                     CmdlineCheck('self_protection', 'defconfig', 'spectre_bhi', 'is not set')))]
        l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spec_store_bypass_disable', 'is not off'),
                 AND(CmdlineCheck('self_protection', 'kspp', 'mitigations', 'auto,nosmt'),
                     CmdlineCheck('self_protection', 'defconfig', 'spec_store_bypass_disable', 'is not set')))]
        l += [OR(CmdlineCheck('self_protection', 'defconfig', 'l1tf', 'is not off'),
                 AND(CmdlineCheck('self_protection', 'kspp', 'mitigations', 'auto,nosmt'),
                     CmdlineCheck('self_protection', 'defconfig', 'l1tf', 'is not set')))]
        l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mds', 'is not off'),
                 AND(CmdlineCheck('self_protection', 'kspp', 'mitigations', 'auto,nosmt'),
                     CmdlineCheck('self_protection', 'defconfig', 'mds', 'is not set')))]
        l += [OR(CmdlineCheck('self_protection', 'defconfig', 'tsx_async_abort', 'is not off'),
                 AND(CmdlineCheck('self_protection', 'kspp', 'mitigations', 'auto,nosmt'),
                     CmdlineCheck('self_protection', 'defconfig', 'tsx_async_abort', 'is not set')))]
        l += [OR(CmdlineCheck('self_protection', 'defconfig', 'srbds', 'is not off'),
                 AND(CmdlineCheck('self_protection', 'kspp', 'mitigations', 'auto,nosmt'),
                     CmdlineCheck('self_protection', 'defconfig', 'srbds', 'is not set')))]
        l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mmio_stale_data', 'is not off'),
                 AND(CmdlineCheck('self_protection', 'kspp', 'mitigations', 'auto,nosmt'),
                     CmdlineCheck('self_protection', 'defconfig', 'mmio_stale_data', 'is not set')))]
        l += [OR(CmdlineCheck('self_protection', 'defconfig', 'retbleed', 'is not off'),
                 AND(CmdlineCheck('self_protection', 'kspp', 'mitigations', 'auto,nosmt'),
                     CmdlineCheck('self_protection', 'defconfig', 'retbleed', 'is not set')))]
        l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spec_rstack_overflow', 'is not off'),
                 AND(CmdlineCheck('self_protection', 'kspp', 'mitigations', 'auto,nosmt'),
                     CmdlineCheck('self_protection', 'defconfig', 'spec_rstack_overflow', 'is not set')))]
        l += [OR(CmdlineCheck('self_protection', 'defconfig', 'gather_data_sampling', 'is not off'),
                 AND(CmdlineCheck('self_protection', 'kspp', 'mitigations', 'auto,nosmt'),
                     CmdlineCheck('self_protection', 'defconfig', 'gather_data_sampling', 'is not set')))]
        l += [OR(CmdlineCheck('self_protection', 'defconfig', 'reg_file_data_sampling', 'is not off'),
                 AND(KconfigCheck('self_protection', 'defconfig', 'MITIGATION_RFDS', 'y'),
                     CmdlineCheck('self_protection', 'kspp', 'mitigations', 'auto,nosmt'),
                     CmdlineCheck('self_protection', 'defconfig', 'reg_file_data_sampling', 'is not set')))]
    if arch == 'ARM64':
        l += [OR(CmdlineCheck('self_protection', 'defconfig', 'kpti', 'is not off'),
                 AND(CmdlineCheck('self_protection', 'kspp', 'mitigations', 'auto,nosmt'),
                     CmdlineCheck('self_protection', 'defconfig', 'kpti', 'is not set')))]
        l += [OR(CmdlineCheck('self_protection', 'defconfig', 'ssbd', 'kernel'),
                 CmdlineCheck('self_protection', 'a13xp0p0v', 'ssbd', 'force-on'),
                 AND(CmdlineCheck('self_protection', 'kspp', 'mitigations', 'auto,nosmt'),
                     CmdlineCheck('self_protection', 'defconfig', 'ssbd', 'is not set')))]
        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', 'on'),
                 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set'))]

    # 'self_protection', 'kspp'
    l += [CmdlineCheck('self_protection', 'kspp', 'slab_merge', 'is not set')] # consequence of 'slab_nomerge' by kspp
    l += [CmdlineCheck('self_protection', 'kspp', 'slub_merge', 'is not set')] # consequence of 'slab_nomerge' by kspp
    l += [CmdlineCheck('self_protection', 'kspp', 'page_alloc.shuffle', '1')]
    l += [CmdlineCheck('self_protection', 'kspp', 'cfi', 'kcfi')]
    l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_nomerge', 'is present'),
             AND(KconfigCheck('self_protection', 'kspp', 'SLAB_MERGE_DEFAULT', 'is not set'),
                 CmdlineCheck('self_protection', 'kspp', 'slab_merge', 'is not set'),
                 CmdlineCheck('self_protection', 'kspp', 'slub_merge', 'is not set')))]
    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', 'hardened_usercopy', '1'),
             AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y'),
                 CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', 'is not set')))]
    l += [AND(CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', 'is not set'),
              KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'))]
              # Consequence of the HARDENED_USERCOPY_FALLBACK check by kspp.
              # Don't require slab_common.usercopy_fallback=0,
              # since HARDENED_USERCOPY_FALLBACK was removed in Linux v5.16.
    l += [OR(CmdlineCheck('self_protection', 'kspp', 'kfence.sample_interval', '100'),
             AND(KconfigCheck('self_protection', 'kspp', 'KFENCE_SAMPLE_INTERVAL', '100'),
                 CmdlineCheck('self_protection', 'kspp', 'kfence.sample_interval', 'is not set')))]
    if arch in ('X86_64', 'ARM64', 'X86_32'):
        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')))]
        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', 'mitigations', 'auto,nosmt')]
        l += [AND(CmdlineCheck('self_protection', 'kspp', 'pti', 'on'),
                  CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set'))]
    if arch == 'ARM64':
        l += [OR(CmdlineCheck('self_protection', 'kspp', 'mitigations', 'auto'),
                 CmdlineCheck('self_protection', 'kspp', 'mitigations', 'is not set'))] # same as 'auto'

    # 'self_protection', 'clipos'
    if arch in ('X86_64', 'X86_32'):
        l += [CmdlineCheck('self_protection', 'clipos', 'iommu', 'force')]

    # 'cut_attack_surface', 'defconfig'
    if arch in ('X86_64', 'X86_32'):
        tsx_not_set = CmdlineCheck('cut_attack_surface', 'defconfig', 'tsx', 'is not set')
        l += [OR(CmdlineCheck('cut_attack_surface', 'defconfig', 'tsx', 'off'),
                 AND(KconfigCheck('cut_attack_surface', 'defconfig', 'X86_INTEL_TSX_MODE_OFF', 'y'),
                     tsx_not_set),
                 AND(KconfigCheck('-', '-', 'CPU_SUP_INTEL', 'is not set'),
                     tsx_not_set))]

    # 'cut_attack_surface', 'kspp'
    l += [CmdlineCheck('cut_attack_surface', 'kspp', 'nosmt', 'is present')] # slow (high performance penalty)
    if arch == 'X86_64':
        l += [OR(CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'none'),
                 KconfigCheck('cut_attack_surface', 'kspp', 'X86_VSYSCALL_EMULATION', 'is not set'),
                 AND(KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y'),
                     CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'is not set')))]
        l += [OR(CmdlineCheck('cut_attack_surface', 'kspp', 'vdso32', '0'),
                 CmdlineCheck('cut_attack_surface', 'a13xp0p0v', 'vdso32', '1'),
                 AND(KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_VDSO', 'is not set'),
                     CmdlineCheck('cut_attack_surface', 'a13xp0p0v', 'vdso32', 'is not set')))] # the vdso32 parameter must not be 2
    if arch == 'X86_32':
        l += [OR(CmdlineCheck('cut_attack_surface', 'kspp', 'vdso32', '0'),
                 CmdlineCheck('cut_attack_surface', 'a13xp0p0v', 'vdso', '0'),
                 CmdlineCheck('cut_attack_surface', 'a13xp0p0v', 'vdso32', '1'),
                 CmdlineCheck('cut_attack_surface', 'a13xp0p0v', 'vdso', '1'),
                 AND(KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_VDSO', 'is not set'),
                     CmdlineCheck('cut_attack_surface', 'a13xp0p0v', 'vdso32', 'is not set'),
                     CmdlineCheck('cut_attack_surface', 'a13xp0p0v', 'vdso', 'is not set')))] # the vdso and vdso32 parameters must not be 2

    # '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

    # 'cut_attack_surface', 'grapheneos'
    l += [CmdlineCheck('cut_attack_surface', 'grapheneos', 'sysrq_always_enabled', 'is not set')]

    # 'cut_attack_surface', 'a13xp0p0v'
    l += [OR(CmdlineCheck('cut_attack_surface', 'a13xp0p0v', 'bdev_allow_write_mounted', '0'),
             AND(KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'BLK_DEV_WRITE_MOUNTED', 'is not set'),
                 CmdlineCheck('cut_attack_surface', 'a13xp0p0v', 'bdev_allow_write_mounted', 'is not set')))]
    if arch == 'X86_64':
        l += [OR(CmdlineCheck('cut_attack_surface', 'a13xp0p0v', 'ia32_emulation', '0'),
                 KconfigCheck('cut_attack_surface', 'kspp', 'IA32_EMULATION', 'is not set'),
                 AND(KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'IA32_EMULATION_DEFAULT_DISABLED', 'y'),
                     CmdlineCheck('cut_attack_surface', 'a13xp0p0v', 'ia32_emulation', 'is not set')))]

    # 'harden_userspace'
    l += [CmdlineCheck('harden_userspace', 'defconfig', 'norandmaps', 'is not set')]


no_kstrtobool_options = [
    'debugfs', # See debugfs_kernel() in fs/debugfs/inode.c
    'mitigations', # See mitigations_parse_cmdline() in kernel/cpu.c
    'pti', # See pti_check_boottime_disable() in arch/x86/mm/pti.c
    'spectre_v2', # See spectre_v2_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
    'spectre_v2_user', # See spectre_v2_parse_user_cmdline() in arch/x86/kernel/cpu/bugs.c
    'spectre_bhi', # See spectre_bhi_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
    'spec_store_bypass_disable', # See ssb_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
    'l1tf', # See l1tf_cmdline() in arch/x86/kernel/cpu/bugs.c
    'mds', # See mds_cmdline() in arch/x86/kernel/cpu/bugs.c
    'tsx_async_abort', # See tsx_async_abort_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
    'srbds', # See srbds_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
    'mmio_stale_data', # See mmio_stale_data_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
    'retbleed', # See retbleed_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
    'rodata', # See set_debug_rodata() in init/main.c
    'ssbd', # See parse_spectre_v4_param() in arch/arm64/kernel/proton-pack.c
    'spec_rstack_overflow', # See srso_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
    'gather_data_sampling', # See gds_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
    'reg_file_data_sampling', # See rfds_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
    'slub_debug', # See setup_slub_debug() in mm/slub.c
    'iommu', # See iommu_setup() in arch/x86/kernel/pci-dma.c
    'vsyscall', # See vsyscall_setup() in arch/x86/entry/vsyscall/vsyscall_64.c
    'vdso32', # See vdso32_setup() in arch/x86/entry/vdso/vdso32-setup.c
    'vdso', # See vdso32_setup() in arch/x86/entry/vdso/vdso32-setup.c
    'cfi', # See cfi_parse_cmdline() in arch/x86/kernel/alternative.c
    'tsx' # See tsx_init() in arch/x86/kernel/cpu/tsx.c
]


def normalize_cmdline_options(option: str, value: str) -> str:
    # Don't normalize the cmdline option values if
    # the Linux kernel doesn't use kstrtobool() for them
    if option in no_kstrtobool_options:
        return value

    # Implement a limited part of the kstrtobool() logic
    if value.lower() in ('1', 'on', 'y', 'yes', 't', 'true'):
        return '1'
    if value.lower() in ('0', 'off', 'n', 'no', 'f', 'false'):
        return '0'

    # Preserve unique values
    return value


# Ideas of security hardening sysctls:
#    what about bpf_jit_enable?
#    vm.mmap_min_addr has a good value
#    nosmt sysfs control file
#    vm.mmap_rnd_bits=max
#    vm.mmap_rnd_compat_bits=max
#    abi.vsyscall32 (any value except 2)
#    net.ipv4.tcp_syncookies=1 (?)

def add_sysctl_checks(l: List[ChecklistObjType], _arch: StrOrNone) -> None:
# This function may be called with arch=None

# Calling the SysctlCheck class constructor:
#   SysctlCheck(reason, decision, name, expected)

    # Use an omnipresent kconfig symbol to see if we have a kconfig file for checking
    have_kconfig = KconfigCheck('-', '-', 'LOCALVERSION', 'is present')

    l += [OR(SysctlCheck('self_protection', 'kspp', 'net.core.bpf_jit_harden', '2'),
             AND(KconfigCheck('-', '-', 'BPF_JIT', 'is not set'),
                 have_kconfig))]
    # Choosing a right value for 'kernel.oops_limit' and 'kernel.warn_limit' is not easy.
    # A small value (e.g. 1, which is recommended by KSPP) allows easy DoS.
    # A large value (e.g. 10000, which is default 'kernel.oops_limit') may miss the exploit attempt.
    # Let's choose 100 as a reasonable compromise.
    l += [SysctlCheck('self_protection', 'a13xp0p0v', 'kernel.oops_limit', '100')]
    l += [SysctlCheck('self_protection', 'a13xp0p0v', 'kernel.warn_limit', '100')]

    l += [SysctlCheck('cut_attack_surface', 'kspp', 'kernel.dmesg_restrict', '1')]
    l += [SysctlCheck('cut_attack_surface', 'kspp', 'kernel.perf_event_paranoid', '3')] # with a custom patch, see https://lwn.net/Articles/696216/
    l += [SysctlCheck('cut_attack_surface', 'kspp', 'user.max_user_namespaces', '0')] # may break the upower daemon in Ubuntu
    l += [SysctlCheck('cut_attack_surface', 'kspp', 'dev.tty.ldisc_autoload', '0')]
    l += [SysctlCheck('cut_attack_surface', 'kspp', 'kernel.kptr_restrict', '2')]
    l += [SysctlCheck('cut_attack_surface', 'kspp', 'dev.tty.legacy_tiocsti', '0')]
    l += [OR(SysctlCheck('cut_attack_surface', 'kspp', 'kernel.kexec_load_disabled', '1'),
             AND(KconfigCheck('-', '-', 'KEXEC_CORE', 'is not set'),
                 have_kconfig))]
    l += [OR(SysctlCheck('cut_attack_surface', 'kspp', 'kernel.unprivileged_bpf_disabled', '1'),
             AND(KconfigCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set'),
                 have_kconfig))]
    l += [OR(SysctlCheck('cut_attack_surface', 'kspp', 'vm.unprivileged_userfaultfd', '0'),
             AND(KconfigCheck('cut_attack_surface', 'grsec', 'USERFAULTFD', 'is not set'),
                 have_kconfig))]
          # At first, it disabled unprivileged userfaultfd,
          # and since v5.11 it enables unprivileged userfaultfd for user-mode only.

    l += [OR(SysctlCheck('cut_attack_surface', 'kspp', 'kernel.modules_disabled', '1'),
             AND(KconfigCheck('cut_attack_surface', 'kspp', 'MODULES', 'is not set'),
                 have_kconfig))] # radical, but may be useful in some cases

    l += [OR(SysctlCheck('cut_attack_surface', 'grsec', 'kernel.io_uring_disabled', '2'),
             AND(KconfigCheck('cut_attack_surface', 'grsec', 'IO_URING', 'is not set'),
                 have_kconfig))] # compatible with the 'IO_URING' kconfig check by grsecurity

    l += [OR(SysctlCheck('cut_attack_surface', 'a13xp0p0v', 'kernel.sysrq', '0'),
             AND(KconfigCheck('cut_attack_surface', 'clipos', 'MAGIC_SYSRQ', 'is not set'),
                 have_kconfig))]

    l += [SysctlCheck('harden_userspace', 'kspp', 'fs.protected_symlinks', '1')]
    l += [SysctlCheck('harden_userspace', 'kspp', 'fs.protected_hardlinks', '1')]
    l += [SysctlCheck('harden_userspace', 'kspp', 'fs.protected_fifos', '2')]
    l += [SysctlCheck('harden_userspace', 'kspp', 'fs.protected_regular', '2')]
    l += [SysctlCheck('harden_userspace', 'kspp', 'fs.suid_dumpable', '0')]
    l += [SysctlCheck('harden_userspace', 'kspp', 'kernel.randomize_va_space', '2')]
    l += [SysctlCheck('harden_userspace', 'kspp', 'kernel.yama.ptrace_scope', '3')]
