4 This tool is for checking the security hardening options of the Linux kernel.
6 Author: Alexander Popov <alex.popov@linux.com>
8 This module is the engine of checks.
11 # pylint: disable=missing-class-docstring,missing-function-docstring
12 # pylint: disable=line-too-long,invalid-name,too-many-branches
14 GREEN_COLOR = '\x1b[32m'
15 RED_COLOR = '\x1b[31m'
18 def colorize_result(input_text):
19 if input_text is None:
21 if input_text.startswith('OK'):
24 assert(input_text.startswith('FAIL:')), f'unexpected result "{input_text}"'
26 return f'{color}{input_text}{COLOR_END}'
30 def __init__(self, reason, decision, name, expected):
31 assert(name and name == name.strip() and len(name.split()) == 1), \
32 f'invalid name "{name}" for {self.__class__.__name__}'
35 assert(decision and decision == decision.strip() and len(decision.split()) == 1), \
36 f'invalid decision "{decision}" for "{name}" check'
37 self.decision = decision
39 assert(reason and reason == reason.strip() and len(reason.split()) == 1), \
40 f'invalid reason "{reason}" for "{name}" check'
43 assert(expected and expected == expected.strip()), \
44 f'invalid expected value "{expected}" for "{name}" check (1)'
45 val_len = len(expected.split())
47 assert(expected in ('is not set', 'is not off')), \
48 f'invalid expected value "{expected}" for "{name}" check (2)'
50 assert(expected == 'is present'), \
51 f'invalid expected value "{expected}" for "{name}" check (3)'
53 assert(val_len == 1), \
54 f'invalid expected value "{expected}" for "{name}" check (4)'
55 self.expected = expected
64 def set_state(self, data):
65 assert(data is None or isinstance(data, str)), \
66 f'invalid state "{data}" for "{self.name}" check'
70 # handle the 'is present' check
71 if self.expected == 'is present':
72 if self.state is None:
73 self.result = 'FAIL: is not present'
75 self.result = 'OK: is present'
78 # handle the 'is not off' option check
79 if self.expected == 'is not off':
80 if self.state == 'off':
81 self.result = 'FAIL: is off'
82 elif self.state == '0':
83 self.result = 'FAIL: is off, "0"'
84 elif self.state is None:
85 self.result = 'FAIL: is off, not found'
87 self.result = f'OK: is not off, "{self.state}"'
90 # handle the option value check
91 if self.expected == self.state:
93 elif self.state is None:
94 if self.expected == 'is not set':
95 self.result = 'OK: is not found'
97 self.result = 'FAIL: is not found'
99 self.result = f'FAIL: "{self.state}"'
101 def table_print(self, _mode, with_results):
102 print(f'{self.name:<40}|{self.type:^7}|{self.expected:^12}|{self.decision:^10}|{self.reason:^18}', end='')
104 print(f'| {colorize_result(self.result)}', end='')
106 def json_dump(self, with_results):
107 dump = [self.name, self.type, self.expected, self.decision, self.reason]
109 dump.append(self.result)
113 class KconfigCheck(OptCheck):
114 def __init__(self, *args, **kwargs):
115 super().__init__(*args, **kwargs)
116 self.name = f'CONFIG_{self.name}'
123 class CmdlineCheck(OptCheck):
129 class SysctlCheck(OptCheck):
136 def __init__(self, ver_expected):
137 assert(ver_expected and isinstance(ver_expected, tuple) and len(ver_expected) == 3), \
138 f'invalid expected version "{ver_expected}" for VersionCheck (1)'
139 assert(all(map(lambda x: isinstance(x, int), ver_expected))), \
140 f'invalid expected version "{ver_expected}" for VersionCheck (2)'
141 self.ver_expected = ver_expected
149 def set_state(self, data):
150 assert(data and isinstance(data, tuple) and len(data) >= 3), \
151 f'invalid version "{data}" for VersionCheck'
155 if self.ver[0] > self.ver_expected[0]:
156 self.result = f'OK: version >= {self.ver_expected}'
158 if self.ver[0] < self.ver_expected[0]:
159 self.result = f'FAIL: version < {self.ver_expected}'
161 # self.ver[0] and self.ver_expected[0] are equal
162 if self.ver[1] > self.ver_expected[1]:
163 self.result = f'OK: version >= {self.ver_expected}'
165 if self.ver[1] < self.ver_expected[1]:
166 self.result = f'FAIL: version < {self.ver_expected}'
168 # self.ver[1] and self.ver_expected[1] are equal too
169 if self.ver[2] >= self.ver_expected[2]:
170 self.result = f'OK: version >= {self.ver_expected}'
172 self.result = f'FAIL: version < {self.ver_expected}'
174 def table_print(self, _mode, with_results):
175 ver_req = f'kernel version >= {self.ver_expected}'
176 print(f'{ver_req:<91}', end='')
178 print(f'| {colorize_result(self.result)}', end='')
181 class ComplexOptCheck:
182 def __init__(self, *opts):
185 f'empty {self.__class__.__name__} check'
186 assert(len(self.opts) != 1), \
187 f'useless {self.__class__.__name__} check: {opts}'
188 assert(isinstance(opts[0], (KconfigCheck, CmdlineCheck, SysctlCheck))), \
189 f'invalid {self.__class__.__name__} check: {opts}'
198 return self.opts[0].name
202 return self.opts[0].expected
204 def table_print(self, mode, with_results):
205 if mode == 'verbose':
206 class_name = f'<<< {self.__class__.__name__} >>>'
207 print(f' {class_name:87}', end='')
209 print(f'| {colorize_result(self.result)}', end='')
212 o.table_print(mode, with_results)
215 o.table_print(mode, False)
217 print(f'| {colorize_result(self.result)}', end='')
219 def json_dump(self, with_results):
220 dump = self.opts[0].json_dump(False)
222 dump.append(self.result)
226 class OR(ComplexOptCheck):
227 # self.opts[0] is the option that this OR-check is about.
229 # OR(<X_is_hardened>, <X_is_disabled>)
230 # OR(<X_is_hardened>, <old_X_is_hardened>)
232 for i, opt in enumerate(self.opts):
234 if opt.result.startswith('OK'):
235 self.result = opt.result
236 # Add more info for additional checks:
238 if opt.result == 'OK':
239 self.result = f'OK: {opt.name} is "{opt.expected}"'
240 elif opt.result == 'OK: is not found':
241 self.result = f'OK: {opt.name} is not found'
242 elif opt.result == 'OK: is present':
243 self.result = f'OK: {opt.name} is present'
244 elif opt.result.startswith('OK: is not off'):
245 self.result = f'OK: {opt.name} is not off'
247 # VersionCheck provides enough info
248 assert(opt.result.startswith('OK: version')), \
249 f'unexpected OK description "{opt.result}"'
251 self.result = self.opts[0].result
254 class AND(ComplexOptCheck):
255 # self.opts[0] is the option that this AND-check is about.
257 # AND(<suboption>, <main_option>)
258 # Suboption is not checked if checking of the main_option is failed.
259 # AND(<X_is_disabled>, <old_X_is_disabled>)
261 for i, opt in reversed(list(enumerate(self.opts))):
264 self.result = opt.result
266 if not opt.result.startswith('OK'):
267 # This FAIL is caused by additional checks,
268 # and not by the main option that this AND-check is about.
269 # Describe the reason of the FAIL.
270 if opt.result.startswith('FAIL: \"') or opt.result == 'FAIL: is not found':
271 self.result = f'FAIL: {opt.name} is not "{opt.expected}"'
272 elif opt.result == 'FAIL: is not present':
273 self.result = f'FAIL: {opt.name} is not present'
274 elif opt.result in ('FAIL: is off', 'FAIL: is off, "0"'):
275 self.result = f'FAIL: {opt.name} is off'
276 elif opt.result == 'FAIL: is off, not found':
277 self.result = f'FAIL: {opt.name} is off, not found'
279 # VersionCheck provides enough info
280 self.result = opt.result
281 assert(opt.result.startswith('FAIL: version')), \
282 f'unexpected FAIL description "{opt.result}"'
286 SIMPLE_OPTION_TYPES = ('kconfig', 'cmdline', 'sysctl', 'version')
289 def populate_simple_opt_with_data(opt, data, data_type):
290 assert(opt.type != 'complex'), \
291 f'unexpected ComplexOptCheck "{opt.name}"'
292 assert(opt.type in SIMPLE_OPTION_TYPES), \
293 f'invalid opt type "{opt.type}"'
294 assert(data_type in SIMPLE_OPTION_TYPES), \
295 f'invalid data type "{data_type}"'
299 if data_type != opt.type:
302 if data_type in ('kconfig', 'cmdline', 'sysctl'):
303 opt.set_state(data.get(opt.name, None))
305 assert(data_type == 'version'), \
306 f'unexpected data type "{data_type}"'
310 def populate_opt_with_data(opt, data, data_type):
311 assert(opt.type != 'version'), 'a single VersionCheck is useless'
312 if opt.type != 'complex':
313 populate_simple_opt_with_data(opt, data, data_type)
316 if o.type != 'complex':
317 populate_simple_opt_with_data(o, data, data_type)
319 # Recursion for nested ComplexOptCheck objects
320 populate_opt_with_data(o, data, data_type)
323 def populate_with_data(checklist, data, data_type):
324 for opt in checklist:
325 populate_opt_with_data(opt, data, data_type)
328 def override_expected_value(checklist, name, new_val):
329 for opt in checklist:
331 assert(opt.type in ('kconfig', 'cmdline', 'sysctl')), \
332 f'overriding an expected value for "{opt.type}" checks is not supported yet'
333 opt.expected = new_val
336 def perform_checks(checklist):
337 for opt in checklist: