#!/usr/bin/python3
"""
-This tool helps me to check Linux kernel options against
-my security hardening preferences for X86_64, ARM64, X86_32, and ARM.
-Let the computers do their job!
+This tool is for checking the security hardening options of the Linux kernel.
Author: Alexander Popov <alex.popov@linux.com>
This module is the engine of checks.
"""
-# pylint: disable=missing-module-docstring,missing-class-docstring,missing-function-docstring
-# pylint: disable=line-too-long,invalid-name,too-many-branches,too-many-statements
+# pylint: disable=missing-class-docstring,missing-function-docstring
+# pylint: disable=line-too-long,invalid-name,too-many-branches
class OptCheck:
self.state = None
self.result = None
- @property
- def type(self):
- return None
-
def check(self):
# handle the 'is present' check
if self.expected == 'is present':
if self.expected == 'is not off':
if self.state == 'off':
self.result = 'FAIL: is off'
- if self.state == '0':
+ elif self.state == '0':
self.result = 'FAIL: is off, "0"'
elif self.state is None:
self.result = 'FAIL: is off, not found'
else:
- self.result = 'OK: is not off, "' + self.state + '"'
+ self.result = f'OK: is not off, "{self.state}"'
return
# handle the option value check
else:
self.result = 'FAIL: is not found'
else:
- self.result = 'FAIL: "' + self.state + '"'
+ self.result = f'FAIL: "{self.state}"'
def table_print(self, _mode, with_results):
print(f'{self.name:<40}|{self.type:^7}|{self.expected:^12}|{self.decision:^10}|{self.reason:^18}', end='')
return 'cmdline'
+class SysctlCheck(OptCheck):
+ @property
+ def type(self):
+ return 'sysctl'
+
+
class VersionCheck:
def __init__(self, ver_expected):
assert(ver_expected and isinstance(ver_expected, tuple) and len(ver_expected) == 2), \
def check(self):
if self.ver[0] > self.ver_expected[0]:
- self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
+ self.result = f'OK: version >= {self.ver_expected[0]}.{self.ver_expected[1]}'
return
if self.ver[0] < self.ver_expected[0]:
- self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
+ self.result = f'FAIL: version < {self.ver_expected[0]}.{self.ver_expected[1]}'
return
if self.ver[1] >= self.ver_expected[1]:
- self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
+ self.result = f'OK: version >= {self.ver_expected[0]}.{self.ver_expected[1]}'
return
- self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
+ self.result = f'FAIL: version < {self.ver_expected[0]}.{self.ver_expected[1]}'
def table_print(self, _mode, with_results):
- ver_req = 'kernel version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
+ ver_req = f'kernel version >= {self.ver_expected[0]}.{self.ver_expected[1]}'
print(f'{ver_req:<91}', end='')
if with_results:
print(f'| {self.result}', end='')
f'empty {self.__class__.__name__} check'
assert(len(self.opts) != 1), \
f'useless {self.__class__.__name__} check: {opts}'
- assert(isinstance(opts[0], (KconfigCheck, CmdlineCheck))), \
+ assert(isinstance(opts[0], (KconfigCheck, CmdlineCheck, SysctlCheck))), \
f'invalid {self.__class__.__name__} check: {opts}'
self.result = None
def table_print(self, mode, with_results):
if mode == 'verbose':
- print(f" {'<<< ' + self.__class__.__name__ + ' >>>':87}", end='')
+ print(f' {"<<< " + self.__class__.__name__ + " >>>":87}', end='')
if with_results:
print(f'| {self.result}', end='')
for o in self.opts:
return
-SIMPLE_OPTION_TYPES = ('kconfig', 'version', 'cmdline')
+SIMPLE_OPTION_TYPES = ('kconfig', 'cmdline', 'sysctl', 'version')
def populate_simple_opt_with_data(opt, data, data_type):
f'invalid opt type "{opt.type}"'
assert(data_type in SIMPLE_OPTION_TYPES), \
f'invalid data type "{data_type}"'
+ assert(data), \
+ 'empty data'
if data_type != opt.type:
return
- if data_type in ('kconfig', 'cmdline'):
+ if data_type in ('kconfig', 'cmdline', 'sysctl'):
opt.state = data.get(opt.name, None)
else:
assert(data_type == 'version'), \
def populate_opt_with_data(opt, data, data_type):
- if opt.type == 'complex':
+ assert(opt.type != 'version'), 'a single VersionCheck is useless'
+ if opt.type != 'complex':
+ populate_simple_opt_with_data(opt, data, data_type)
+ else:
for o in opt.opts:
- if o.type == 'complex':
+ if o.type != 'complex':
+ populate_simple_opt_with_data(o, data, data_type)
+ else:
# Recursion for nested ComplexOptCheck objects
populate_opt_with_data(o, data, data_type)
- else:
- populate_simple_opt_with_data(o, data, data_type)
- else:
- assert(opt.type in ('kconfig', 'cmdline')), \
- f'bad type "{opt.type}" for a simple check'
- populate_simple_opt_with_data(opt, data, data_type)
def populate_with_data(checklist, data, data_type):
populate_opt_with_data(opt, data, data_type)
+def override_expected_value(checklist, name, new_val):
+ for opt in checklist:
+ if opt.name == name:
+ assert(opt.type in ('kconfig', 'cmdline', 'sysctl')), \
+ f'overriding an expected value for "{opt.type}" checks is not supported yet'
+ opt.expected = new_val
+
+
def perform_checks(checklist):
for opt in checklist:
opt.check()