xref: /aosp_15_r20/system/sepolicy/tests/sepolicy_tests.py (revision e4a36f4174b17bbab9dc043f4a65dc8d87377290)
1# Copyright 2021 The Android Open Source Project
2#
3# Licensed under the Apache License, Version 2.0 (the "License");
4# you may not use this file except in compliance with the License.
5# You may obtain a copy of the License at
6#
7#     http://www.apache.org/licenses/LICENSE-2.0
8#
9# Unless required by applicable law or agreed to in writing, software
10# distributed under the License is distributed on an "AS IS" BASIS,
11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12# See the License for the specific language governing permissions and
13# limitations under the License.
14
15from optparse import OptionParser
16from optparse import Option, OptionValueError
17import os
18import pkgutil
19import policy
20import re
21import shutil
22import sys
23import tempfile
24
25SHARED_LIB_EXTENSION = '.dylib' if sys.platform == 'darwin' else '.so'
26
27#############################################################
28# Tests
29#############################################################
30def TestDataTypeViolations(pol):
31    return pol.AssertPathTypesHaveAttr(["/data/"], [], "data_file_type")
32
33def TestSystemTypeViolations(pol):
34    partitions = ["/system/", "/system_ext/", "/product/"]
35    exceptions = [
36        # devices before treble don't have a vendor partition
37        "/system/vendor/",
38
39        # overlay files are mounted over vendor
40        "/product/overlay/",
41        "/product/vendor_overlay/",
42        "/system/overlay/",
43        "/system/product/overlay/",
44        "/system/product/vendor_overlay/",
45        "/system/system_ext/overlay/",
46        "/system_ext/overlay/",
47
48        # adb_keys_file hasn't been a system_file_type
49        "/product/etc/security/adb_keys",
50        "/system/product/etc/security/adb_keys",
51    ]
52
53    return pol.AssertPathTypesHaveAttr(partitions, exceptions, "system_file_type")
54
55def TestBpffsTypeViolations(pol):
56    return pol.AssertGenfsFilesystemTypesHaveAttr("bpf", "bpffs_type")
57
58def TestProcTypeViolations(pol):
59    return pol.AssertGenfsFilesystemTypesHaveAttr("proc", "proc_type")
60
61def TestSysfsTypeViolations(pol):
62    ret = pol.AssertGenfsFilesystemTypesHaveAttr("sysfs", "sysfs_type")
63    ret += pol.AssertPathTypesHaveAttr(["/sys/"], ["/sys/kernel/debug/",
64                                    "/sys/kernel/tracing"], "sysfs_type")
65    return ret
66
67def TestDebugfsTypeViolations(pol):
68    ret = pol.AssertGenfsFilesystemTypesHaveAttr("debugfs", "debugfs_type")
69    ret += pol.AssertPathTypesHaveAttr(["/sys/kernel/debug/",
70                                    "/sys/kernel/tracing"], [], "debugfs_type")
71    return ret
72
73def TestTracefsTypeViolations(pol):
74    ret = pol.AssertGenfsFilesystemTypesHaveAttr("tracefs", "tracefs_type")
75    ret += pol.AssertPathTypesHaveAttr(["/sys/kernel/tracing"], [], "tracefs_type")
76    ret += pol.AssertPathTypesDoNotHaveAttr(["/sys/kernel/debug"],
77                                            ["/sys/kernel/debug/tracing"], "tracefs_type",
78                                            [])
79    return ret
80
81def TestVendorTypeViolations(pol):
82    partitions = ["/vendor/", "/odm/"]
83    exceptions = [
84        "/vendor/etc/selinux/",
85        "/vendor/odm/etc/selinux/",
86        "/odm/etc/selinux/",
87    ]
88    return pol.AssertPathTypesHaveAttr(partitions, exceptions, "vendor_file_type")
89
90def TestCoreDataTypeViolations(pol):
91    ret = pol.AssertPathTypesHaveAttr(["/data/"], ["/data/vendor",
92            "/data/vendor_ce", "/data/vendor_de"], "core_data_file_type")
93    ret += pol.AssertPathTypesDoNotHaveAttr(["/data/vendor/", "/data/vendor_ce/",
94        "/data/vendor_de/"], [], "core_data_file_type")
95    return ret
96
97def TestPropertyTypeViolations(pol):
98    return pol.AssertPropertyOwnersAreExclusive()
99
100def TestAppDataTypeViolations(pol):
101    # Types with the app_data_file_type should only be used for app data files
102    # (/data/data/package.name etc) via seapp_contexts, and never applied
103    # explicitly to other files.
104    partitions = [
105        "/data/",
106        "/vendor/",
107        "/odm/",
108        "/product/",
109    ]
110    exceptions = [
111        # These are used for app data files for the corresponding user and
112        # assorted other files.
113        # TODO(b/172812577): Use different types for the different purposes
114        "shell_data_file",
115        "bluetooth_data_file",
116        "nfc_data_file",
117        "radio_data_file",
118    ]
119    return pol.AssertPathTypesDoNotHaveAttr(partitions, [], "app_data_file_type",
120                                            exceptions)
121def TestDmaHeapDevTypeViolations(pol):
122    return pol.AssertPathTypesHaveAttr(["/dev/dma_heap/"], [],
123                                       "dmabuf_heap_device_type")
124
125def TestCoredomainViolations(test_policy):
126    # verify that all domains launched from /system have the coredomain
127    # attribute
128    ret = ""
129
130    for d in test_policy.alldomains:
131        domain = test_policy.alldomains[d]
132        if domain.fromSystem and domain.fromVendor:
133            ret += "The following domain is system and vendor: " + d + "\n"
134
135    for domain in test_policy.alldomains.values():
136        ret += domain.error
137
138    violators = []
139    for d in test_policy.alldomains:
140        domain = test_policy.alldomains[d]
141        if domain.fromSystem and "coredomain" not in domain.attributes:
142                violators.append(d);
143    if len(violators) > 0:
144        ret += "The following domain(s) must be associated with the "
145        ret += "\"coredomain\" attribute because they are executed off of "
146        ret += "/system:\n"
147        ret += " ".join(str(x) for x in sorted(violators)) + "\n"
148
149    # verify that all domains launched form /vendor do not have the coredomain
150    # attribute
151    violators = []
152    for d in test_policy.alldomains:
153        domain = test_policy.alldomains[d]
154        if domain.fromVendor and "coredomain" in domain.attributes:
155            violators.append(d)
156    if len(violators) > 0:
157        ret += "The following domains must not be associated with the "
158        ret += "\"coredomain\" attribute because they are executed off of "
159        ret += "/vendor or /system/vendor:\n"
160        ret += " ".join(str(x) for x in sorted(violators)) + "\n"
161
162    return ret
163
164def TestViolatorAttribute(test_policy, attribute):
165    # TODO(b/113124961): re-enable once all violator attributes are removed.
166    return ""
167
168    # ret = ""
169    # return ret
170
171    # violators = test_policy.DomainsWithAttribute(attribute)
172    # if len(violators) > 0:
173    #    ret += "SELinux: The following domains violate the Treble ban "
174    #    ret += "against use of the " + attribute + " attribute: "
175    #    ret += " ".join(str(x) for x in sorted(violators)) + "\n"
176    # return ret
177
178def TestViolatorAttributes(test_policy):
179    ret = ""
180    ret += TestViolatorAttribute(test_policy, "socket_between_core_and_vendor_violators")
181    ret += TestViolatorAttribute(test_policy, "vendor_executes_system_violators")
182    return ret
183
184def TestIsolatedAttributeConsistency(test_policy):
185    permissionAllowList = {
186        # access given from technical_debt.cil
187        "codec2_config_prop" : ["file"],
188        "device_config_nnapi_native_prop":["file"],
189        "gpu_device": ["dir"],
190        "hal_allocator_default":["binder", "fd"],
191        "hal_codec2": ["binder", "fd"],
192        "hal_codec2_hwservice":["hwservice_manager"],
193        "hal_graphics_allocator": ["binder", "fd"],
194        "hal_graphics_allocator_service":["service_manager"],
195        "hal_graphics_allocator_hwservice":["hwservice_manager"],
196        "hal_graphics_allocator_server":["binder", "service_manager"],
197        "hal_graphics_mapper_hwservice":["hwservice_manager"],
198        "hal_graphics_mapper_service":["service_manager"],
199        "hal_neuralnetworks": ["binder", "fd"],
200        "hal_neuralnetworks_service": ["service_manager"],
201        "hal_neuralnetworks_hwservice":["hwservice_manager"],
202        "hal_omx_hwservice":["hwservice_manager"],
203        "hidl_allocator_hwservice":["hwservice_manager"],
204        "hidl_manager_hwservice":["hwservice_manager"],
205        "hidl_memory_hwservice":["hwservice_manager"],
206        "hidl_token_hwservice":["hwservice_manager"],
207        "hwservicemanager":["binder"],
208        "hwservicemanager_prop":["file"],
209        "mediacodec":["binder", "fd"],
210        "mediaswcodec":["binder", "fd"],
211        "media_variant_prop":["file"],
212        "nnapi_ext_deny_product_prop":["file"],
213        "servicemanager":["fd"],
214        "sysfs_gpu": ["file"],
215        "toolbox_exec": ["file"],
216        # extra types being granted to isolated_compute_app
217        "isolated_compute_allowed":["service_manager", "chr_file"],
218    }
219
220    def resolveHalServerSubtype(target):
221        # permission given as a client in technical_debt.cil
222        hal_server_attributes = [
223            "hal_codec2_server",
224            "hal_graphics_allocator_server",
225            "hal_neuralnetworks_server"]
226
227        for attr in hal_server_attributes:
228            if target in test_policy.pol.QueryTypeAttribute(Type=attr, IsAttr=True):
229                return attr.rsplit("_", 1)[0]
230        return target
231
232    def checkIsolatedComputeAllowed(tctx, tclass):
233        # check if the permission is in isolated_compute_allowed
234        allowedMemberTypes = test_policy.pol.QueryTypeAttribute(Type="isolated_compute_allowed_service", IsAttr=True) \
235            .union(test_policy.pol.QueryTypeAttribute(Type="isolated_compute_allowed_device", IsAttr=True))
236        return tctx in allowedMemberTypes and tclass in permissionAllowList["isolated_compute_allowed"]
237
238    def checkPermissions(permissions):
239        violated_permissions = []
240        for perm in permissions:
241            tctx, tclass, p = perm.split(":")
242            tctx = resolveHalServerSubtype(tctx)
243            # check unwanted permissions
244            if not checkIsolatedComputeAllowed(tctx, tclass) and \
245                ( tctx not in permissionAllowList \
246                    or tclass not in permissionAllowList[tctx] \
247                    or ( p == "write") \
248                    or ( p == "rw_file_perms") ):
249                violated_permissions += [perm]
250        return violated_permissions
251
252    ret = ""
253
254    isolatedMemberTypes = test_policy.pol.QueryTypeAttribute(Type="isolated_app_all", IsAttr=True)
255    baseRules = test_policy.pol.QueryExpandedTERule(scontext=["isolated_app"])
256    basePermissionSet = set([":".join([rule.tctx, rule.tclass, perm])
257                            for rule in baseRules for perm in rule.perms])
258    for subType in isolatedMemberTypes:
259        if subType == "isolated_app" : continue
260        currentTypeRule = test_policy.pol.QueryExpandedTERule(scontext=[subType])
261        typePermissionSet = set([":".join([rule.tctx, rule.tclass, perm])
262                                for rule in currentTypeRule for perm in rule.perms
263                                if not rule.tctx in [subType, subType + "_userfaultfd"]])
264        deltaPermissionSet = typePermissionSet.difference(basePermissionSet)
265        violated_permissions = checkPermissions(list(deltaPermissionSet))
266        for perm in violated_permissions:
267            ret += "allow %s %s:%s %s \n" % (subType, *perm.split(":"))
268
269    if ret:
270        ret = ("Found prohibited permission granted for isolated like types. " + \
271            "Please replace your allow statements that involve \"-isolated_app\" with " + \
272            "\"-isolated_app_all\". Violations are shown as the following: \n")  + ret
273    return ret
274
275def TestDevTypeViolations(pol):
276    exceptions = [
277        "/dev/socket",
278    ]
279    exceptionTypes = [
280        "boringssl_self_test_marker",  # /dev/boringssl/selftest
281        "cgroup_rc_file",              # /dev/cgroup.rc
282        "dev_cpu_variant",             # /dev/cpu_variant:{arch}
283        "fscklogs",                    # /dev/fscklogs
284        "properties_serial",           # /dev/__properties__/properties_serial
285        "property_info",               # /dev/__properties__/property_info
286        "runtime_event_log_tags_file", # /dev/event-log-tags
287    ]
288    return pol.AssertPathTypesHaveAttr(["/dev"], exceptions,
289                                       "dev_type", exceptionTypes)
290
291###
292# extend OptionParser to allow the same option flag to be used multiple times.
293# This is used to allow multiple file_contexts files and tests to be
294# specified.
295#
296class MultipleOption(Option):
297    ACTIONS = Option.ACTIONS + ("extend",)
298    STORE_ACTIONS = Option.STORE_ACTIONS + ("extend",)
299    TYPED_ACTIONS = Option.TYPED_ACTIONS + ("extend",)
300    ALWAYS_TYPED_ACTIONS = Option.ALWAYS_TYPED_ACTIONS + ("extend",)
301
302    def take_action(self, action, dest, opt, value, values, parser):
303        if action == "extend":
304            values.ensure_value(dest, []).append(value)
305        else:
306            Option.take_action(self, action, dest, opt, value, values, parser)
307
308TEST_NAMES = [ name for name in dir() if name.startswith('Test') ]
309
310def do_main(libpath):
311    """
312    Args:
313        libpath: string, path to libsepolwrap.so
314    """
315    usage = "sepolicy_tests -f vendor_file_contexts -f "
316    usage +="plat_file_contexts -p policy [--test test] [--help]"
317    parser = OptionParser(option_class=MultipleOption, usage=usage)
318    parser.add_option("-f", "--file_contexts", dest="file_contexts",
319            metavar="FILE", action="extend", type="string")
320    parser.add_option("-p", "--policy", dest="policy", metavar="FILE")
321    parser.add_option("-t", "--test", dest="test", action="extend",
322            help="Test options include "+str(TEST_NAMES))
323
324    (options, args) = parser.parse_args()
325
326    if not options.policy:
327        sys.exit("Must specify monolithic policy file\n" + parser.usage)
328    if not os.path.exists(options.policy):
329        sys.exit("Error: policy file " + options.policy + " does not exist\n"
330                + parser.usage)
331
332    if not options.file_contexts:
333        sys.exit("Error: Must specify file_contexts file(s)\n" + parser.usage)
334    for f in options.file_contexts:
335        if not os.path.exists(f):
336            sys.exit("Error: File_contexts file " + f + " does not exist\n" +
337                    parser.usage)
338
339    pol = policy.Policy(options.policy, options.file_contexts, libpath)
340    test_policy = policy.TestPolicy()
341    test_policy.setup(pol)
342
343    results = ""
344    # If an individual test is not specified, run all tests.
345    if options.test is None or "TestBpffsTypeViolations" in options.test:
346        results += TestBpffsTypeViolations(pol)
347    if options.test is None or "TestDataTypeViolations" in options.test:
348        results += TestDataTypeViolations(pol)
349    if options.test is None or "TestProcTypeViolations" in options.test:
350        results += TestProcTypeViolations(pol)
351    if options.test is None or "TestSysfsTypeViolations" in options.test:
352        results += TestSysfsTypeViolations(pol)
353    if options.test is None or "TestSystemTypeViolations" in options.test:
354        results += TestSystemTypeViolations(pol)
355    if options.test is None or "TestDebugfsTypeViolations" in options.test:
356        results += TestDebugfsTypeViolations(pol)
357    if options.test is None or "TestTracefsTypeViolations" in options.test:
358        results += TestTracefsTypeViolations(pol)
359    if options.test is None or "TestVendorTypeViolations" in options.test:
360        results += TestVendorTypeViolations(pol)
361    if options.test is None or "TestCoreDataTypeViolations" in options.test:
362        results += TestCoreDataTypeViolations(pol)
363    if options.test is None or "TestPropertyTypeViolations" in options.test:
364        results += TestPropertyTypeViolations(pol)
365    if options.test is None or "TestAppDataTypeViolations" in options.test:
366        results += TestAppDataTypeViolations(pol)
367    if options.test is None or "TestDmaHeapDevTypeViolations" in options.test:
368        results += TestDmaHeapDevTypeViolations(pol)
369    if options.test is None or "TestCoredomainViolations" in options.test:
370        results += TestCoredomainViolations(test_policy)
371    if options.test is None or "TestViolatorAttributes" in options.test:
372        results += TestViolatorAttributes(test_policy)
373    if options.test is None or "TestIsolatedAttributeConsistency" in options.test:
374        results += TestIsolatedAttributeConsistency(test_policy)
375
376    # dev type test won't be run as default
377    if options.test and "TestDevTypeViolations" in options.test:
378        results += TestDevTypeViolations(pol)
379
380    if len(results) > 0:
381        sys.exit(results)
382
383if __name__ == '__main__':
384    temp_dir = tempfile.mkdtemp()
385    try:
386        libname = "libsepolwrap" + SHARED_LIB_EXTENSION
387        libpath = os.path.join(temp_dir, libname)
388        with open(libpath, "wb") as f:
389            blob = pkgutil.get_data("sepolicy_tests", libname)
390            if not blob:
391                sys.exit("Error: libsepolwrap does not exist. Is this binary corrupted?\n")
392            f.write(blob)
393        do_main(libpath)
394    finally:
395        shutil.rmtree(temp_dir)
396