Support separate sysctl checking (without kconfig)

[kconfig-hardened-check.git] / kconfig_hardened_check / checks.py

diff --git a/kconfig_hardened_check/checks.py b/kconfig_hardened_check/checks.py
index e30746c9fc0c3af0f4a60ef75a8f8d73b486e7d1..4957ad5c4e1a2202267b269d8f400b9bebd3a741 100644 (file)
--- a/kconfig_hardened_check/checks.py
+++ b/kconfig_hardened_check/checks.py
@@ -15,6 +15,8 @@ from .engine import KconfigCheck, CmdlineCheck, SysctlCheck, VersionCheck, OR, A
 
 
 def add_kconfig_checks(l, arch):
+    assert(arch), 'empty arch'
+
     # Calling the KconfigCheck class constructor:
     #     KconfigCheck(reason, decision, name, expected)
     #
@@ -379,6 +381,8 @@ def add_kconfig_checks(l, arch):
 
 
 def add_cmdline_checks(l, arch):
+    assert(arch), 'empty arch'
+
     # Calling the CmdlineCheck class constructor:
     #     CmdlineCheck(reason, decision, name, expected)
     #
@@ -574,20 +578,14 @@ def normalize_cmdline_options(option, value):
     return value
 
 
-def add_sysctl_checks(l, arch):
 # TODO: draft of security hardening sysctls:
 #    kernel.kptr_restrict=2 (or 1?)
-#    kernel.perf_event_paranoid=2 (or 3 with a custom patch, see https://lwn.net/Articles/696216/)
-#    kernel.kexec_load_disabled=1
 #    kernel.yama.ptrace_scope=3
-#    user.max_user_namespaces=0 (for Debian, also see kernel.unprivileged_userns_clone)
 #    what about bpf_jit_enable?
-#    kernel.unprivileged_bpf_disabled=1
 #    vm.unprivileged_userfaultfd=0
 #        (at first, it disabled unprivileged userfaultfd,
 #         and since v5.11 it enables unprivileged userfaultfd for user-mode only)
 #    vm.mmap_min_addr has a good value
-#    dev.tty.ldisc_autoload=0
 #    fs.protected_symlinks=1
 #    fs.protected_hardlinks=1
 #    fs.protected_fifos=2
@@ -603,10 +601,18 @@ def add_sysctl_checks(l, arch):
 #    kernel.oops_limit (think about a proper value)
 #    kernel.warn_limit (think about a proper value)
 #    net.ipv4.tcp_syncookies=1 (?)
-#
+
+def add_sysctl_checks(l, arch):
+# This function may be called with arch=None
+
 # Calling the SysctlCheck class constructor:
 #   SysctlCheck(reason, decision, name, expected)
 
     l += [SysctlCheck('self_protection', 'kspp', 'net.core.bpf_jit_harden', '2')]
 
     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', 'kernel.kexec_load_disabled', '1')]
+    l += [SysctlCheck('cut_attack_surface', 'kspp', 'user.max_user_namespaces', '0')]
+    l += [SysctlCheck('cut_attack_surface', 'kspp', 'dev.tty.ldisc_autoload', '0')]
+    l += [SysctlCheck('cut_attack_surface', 'kspp', 'kernel.unprivileged_bpf_disabled', '1')]