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'
139 self.ver_expected = ver_expected
147 def set_state(self, data):
148 assert(data and isinstance(data, tuple) and len(data) >= 3), \
149 f'invalid version "{data}" for VersionCheck'
153 if self.ver[0] > self.ver_expected[0]:
154 self.result = f'OK: version >= {self.ver_expected}'
156 if self.ver[0] < self.ver_expected[0]:
157 self.result = f'FAIL: version < {self.ver_expected}'
159 # self.ver[0] and self.ver_expected[0] are equal
160 if self.ver[1] > self.ver_expected[1]:
161 self.result = f'OK: version >= {self.ver_expected}'
163 if self.ver[1] < self.ver_expected[1]:
164 self.result = f'FAIL: version < {self.ver_expected}'
166 # self.ver[1] and self.ver_expected[1] are equal too
167 if self.ver[2] >= self.ver_expected[2]:
168 self.result = f'OK: version >= {self.ver_expected}'
170 self.result = f'FAIL: version < {self.ver_expected}'
172 def table_print(self, _mode, with_results):
173 ver_req = f'kernel version >= {self.ver_expected}'
174 print(f'{ver_req:<91}', end='')
176 print(f'| {colorize_result(self.result)}', end='')
179 class ComplexOptCheck:
180 def __init__(self, *opts):
183 f'empty {self.__class__.__name__} check'
184 assert(len(self.opts) != 1), \
185 f'useless {self.__class__.__name__} check: {opts}'
186 assert(isinstance(opts[0], (KconfigCheck, CmdlineCheck, SysctlCheck))), \
187 f'invalid {self.__class__.__name__} check: {opts}'
196 return self.opts[0].name
200 return self.opts[0].expected
202 def table_print(self, mode, with_results):
203 if mode == 'verbose':
204 class_name = f'<<< {self.__class__.__name__} >>>'
205 print(f' {class_name:87}', end='')
207 print(f'| {colorize_result(self.result)}', end='')
210 o.table_print(mode, with_results)
213 o.table_print(mode, False)
215 print(f'| {colorize_result(self.result)}', end='')
217 def json_dump(self, with_results):
218 dump = self.opts[0].json_dump(False)
220 dump.append(self.result)
224 class OR(ComplexOptCheck):
225 # self.opts[0] is the option that this OR-check is about.
227 # OR(<X_is_hardened>, <X_is_disabled>)
228 # OR(<X_is_hardened>, <old_X_is_hardened>)
230 for i, opt in enumerate(self.opts):
232 if opt.result.startswith('OK'):
233 self.result = opt.result
234 # Add more info for additional checks:
236 if opt.result == 'OK':
237 self.result = f'OK: {opt.name} is "{opt.expected}"'
238 elif opt.result == 'OK: is not found':
239 self.result = f'OK: {opt.name} is not found'
240 elif opt.result == 'OK: is present':
241 self.result = f'OK: {opt.name} is present'
242 elif opt.result.startswith('OK: is not off'):
243 self.result = f'OK: {opt.name} is not off'
245 # VersionCheck provides enough info
246 assert(opt.result.startswith('OK: version')), \
247 f'unexpected OK description "{opt.result}"'
249 self.result = self.opts[0].result
252 class AND(ComplexOptCheck):
253 # self.opts[0] is the option that this AND-check is about.
255 # AND(<suboption>, <main_option>)
256 # Suboption is not checked if checking of the main_option is failed.
257 # AND(<X_is_disabled>, <old_X_is_disabled>)
259 for i, opt in reversed(list(enumerate(self.opts))):
262 self.result = opt.result
264 if not opt.result.startswith('OK'):
265 # This FAIL is caused by additional checks,
266 # and not by the main option that this AND-check is about.
267 # Describe the reason of the FAIL.
268 if opt.result.startswith('FAIL: \"') or opt.result == 'FAIL: is not found':
269 self.result = f'FAIL: {opt.name} is not "{opt.expected}"'
270 elif opt.result == 'FAIL: is not present':
271 self.result = f'FAIL: {opt.name} is not present'
272 elif opt.result in ('FAIL: is off', 'FAIL: is off, "0"'):
273 self.result = f'FAIL: {opt.name} is off'
274 elif opt.result == 'FAIL: is off, not found':
275 self.result = f'FAIL: {opt.name} is off, not found'
277 # VersionCheck provides enough info
278 self.result = opt.result
279 assert(opt.result.startswith('FAIL: version')), \
280 f'unexpected FAIL description "{opt.result}"'
284 SIMPLE_OPTION_TYPES = ('kconfig', 'cmdline', 'sysctl', 'version')
287 def populate_simple_opt_with_data(opt, data, data_type):
288 assert(opt.type != 'complex'), \
289 f'unexpected ComplexOptCheck "{opt.name}"'
290 assert(opt.type in SIMPLE_OPTION_TYPES), \
291 f'invalid opt type "{opt.type}"'
292 assert(data_type in SIMPLE_OPTION_TYPES), \
293 f'invalid data type "{data_type}"'
297 if data_type != opt.type:
300 if data_type in ('kconfig', 'cmdline', 'sysctl'):
301 opt.set_state(data.get(opt.name, None))
303 assert(data_type == 'version'), \
304 f'unexpected data type "{data_type}"'
308 def populate_opt_with_data(opt, data, data_type):
309 assert(opt.type != 'version'), 'a single VersionCheck is useless'
310 if opt.type != 'complex':
311 populate_simple_opt_with_data(opt, data, data_type)
314 if o.type != 'complex':
315 populate_simple_opt_with_data(o, data, data_type)
317 # Recursion for nested ComplexOptCheck objects
318 populate_opt_with_data(o, data, data_type)
321 def populate_with_data(checklist, data, data_type):
322 for opt in checklist:
323 populate_opt_with_data(opt, data, data_type)
326 def override_expected_value(checklist, name, new_val):
327 for opt in checklist:
329 assert(opt.type in ('kconfig', 'cmdline', 'sysctl')), \
330 f'overriding an expected value for "{opt.type}" checks is not supported yet'
331 opt.expected = new_val
334 def perform_checks(checklist):
335 for opt in checklist: