| # Copyright 2021 The Android Open Source Project |
| # |
| # Licensed under the Apache License, Version 2.0 (the "License"); |
| # you may not use this file except in compliance with the License. |
| # You may obtain a copy of the License at |
| # |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| # |
| # Unless required by applicable law or agreed to in writing, software |
| # distributed under the License is distributed on an "AS IS" BASIS, |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| # See the License for the specific language governing permissions and |
| # limitations under the License. |
| |
| from optparse import OptionParser |
| from optparse import Option, OptionValueError |
| import os |
| import mini_parser |
| import pkgutil |
| import policy |
| from policy import MatchPathPrefix |
| import re |
| import shutil |
| import sys |
| import tempfile |
| |
| DEBUG=False |
| SHARED_LIB_EXTENSION = '.dylib' if sys.platform == 'darwin' else '.so' |
| |
| # TODO(b/266998144): consider rename this file. |
| |
| ''' |
| Use file_contexts and policy to verify Treble requirements |
| are not violated. |
| ''' |
| coredomainAllowlist = { |
| # TODO: how do we make sure vendor_init doesn't have bad coupling with |
| # /vendor? It is the only system process which is not coredomain. |
| 'vendor_init', |
| # TODO(b/152813275): need to avoid allowlist for rootdir |
| "modprobe", |
| "slideshow", |
| } |
| |
| class scontext: |
| def __init__(self): |
| self.fromSystem = False |
| self.fromVendor = False |
| self.coredomain = False |
| self.appdomain = False |
| self.attributes = set() |
| self.entrypoints = [] |
| self.entrypointpaths = [] |
| self.error = "" |
| |
| |
| class TestPolicy: |
| """A policy loaded in memory with its domains easily accessible.""" |
| |
| def __init__(self): |
| self.alldomains = {} |
| self.coredomains = set() |
| self.appdomains = set() |
| self.vendordomains = set() |
| self.pol = None |
| |
| # compat vars |
| self.alltypes = set() |
| self.oldalltypes = set() |
| self.compatMapping = None |
| self.pubtypes = set() |
| |
| # Distinguish between PRODUCT_FULL_TREBLE and PRODUCT_FULL_TREBLE_OVERRIDE |
| self.FakeTreble = False |
| |
| def GetAllDomains(self): |
| for result in self.pol.QueryTypeAttribute("domain", True): |
| self.alldomains[result] = scontext() |
| |
| def GetAppDomains(self): |
| for d in self.alldomains: |
| # The application of the "appdomain" attribute is trusted because core |
| # selinux policy contains neverallow rules that enforce that only zygote |
| # and runas spawned processes may transition to processes that have |
| # the appdomain attribute. |
| if "appdomain" in self.alldomains[d].attributes: |
| self.alldomains[d].appdomain = True |
| self.appdomains.add(d) |
| |
| def GetCoreDomains(self): |
| for d in self.alldomains: |
| domain = self.alldomains[d] |
| # TestCoredomainViolations will verify if coredomain was incorrectly |
| # applied. |
| if "coredomain" in domain.attributes: |
| domain.coredomain = True |
| self.coredomains.add(d) |
| # check whether domains are executed off of /system or /vendor |
| if d in coredomainAllowlist: |
| continue |
| # TODO(b/153112003): add checks to prevent app domains from being |
| # incorrectly labeled as coredomain. Apps don't have entrypoints as |
| # they're always dynamically transitioned to by zygote. |
| if d in self.appdomains: |
| continue |
| # TODO(b/153112747): need to handle cases where there is a dynamic |
| # transition OR there happens to be no context in AOSP files. |
| if not domain.entrypointpaths: |
| continue |
| |
| for path in domain.entrypointpaths: |
| vendor = any(MatchPathPrefix(path, prefix) for prefix in |
| ["/vendor", "/odm"]) |
| system = any(MatchPathPrefix(path, prefix) for prefix in |
| ["/init", "/system_ext", "/product" ]) |
| |
| # only mark entrypoint as system if it is not in legacy /system/vendor |
| if MatchPathPrefix(path, "/system/vendor"): |
| vendor = True |
| elif MatchPathPrefix(path, "/system"): |
| system = True |
| |
| if not vendor and not system: |
| domain.error += "Unrecognized entrypoint for " + d + " at " + path + "\n" |
| |
| domain.fromSystem = domain.fromSystem or system |
| domain.fromVendor = domain.fromVendor or vendor |
| |
| ### |
| # Add the entrypoint type and path(s) to each domain. |
| # |
| def GetDomainEntrypoints(self): |
| for x in self.pol.QueryExpandedTERule(tclass=set(["file"]), perms=set(["entrypoint"])): |
| if not x.sctx in self.alldomains: |
| continue |
| self.alldomains[x.sctx].entrypoints.append(str(x.tctx)) |
| # postinstall_file represents a special case specific to A/B OTAs. |
| # Update_engine mounts a partition and relabels it postinstall_file. |
| # There is no file_contexts entry associated with postinstall_file |
| # so skip the lookup. |
| if x.tctx == "postinstall_file": |
| continue |
| entrypointpath = self.pol.QueryFc(x.tctx) |
| if not entrypointpath: |
| continue |
| self.alldomains[x.sctx].entrypointpaths.extend(entrypointpath) |
| |
| ### |
| # Get attributes associated with each domain |
| # |
| def GetAttributes(self): |
| for domain in self.alldomains: |
| for result in self.pol.QueryTypeAttribute(domain, False): |
| self.alldomains[domain].attributes.add(result) |
| |
| def setup(self, pol): |
| self.pol = pol |
| self.GetAllDomains() |
| self.GetAttributes() |
| self.GetDomainEntrypoints() |
| self.GetAppDomains() |
| self.GetCoreDomains() |
| |
| def GetAllTypes(self, basepol, oldpol): |
| self.alltypes = basepol.GetAllTypes(False) |
| self.oldalltypes = oldpol.GetAllTypes(False) |
| |
| # setup for the policy compatibility tests |
| def compatSetup(self, basepol, oldpol, mapping, types): |
| self.GetAllTypes(basepol, oldpol) |
| self.compatMapping = mapping |
| self.pubtypes = types |
| |
| def DomainsWithAttribute(self, attr): |
| domains = [] |
| for domain in self.alldomains: |
| if attr in self.alldomains[domain].attributes: |
| domains.append(domain) |
| return domains |
| |
| def PrintScontexts(self): |
| for d in sorted(self.alldomains.keys()): |
| sctx = self.alldomains[d] |
| print(d) |
| print("\tcoredomain="+str(sctx.coredomain)) |
| print("\tappdomain="+str(sctx.appdomain)) |
| print("\tfromSystem="+str(sctx.fromSystem)) |
| print("\tfromVendor="+str(sctx.fromVendor)) |
| print("\tattributes="+str(sctx.attributes)) |
| print("\tentrypoints="+str(sctx.entrypoints)) |
| print("\tentrypointpaths=") |
| if sctx.entrypointpaths is not None: |
| for path in sctx.entrypointpaths: |
| print("\t\t"+str(path)) |
| |
| |
| ############################################################# |
| # Tests |
| ############################################################# |
| def TestCoredomainViolations(test_policy): |
| # verify that all domains launched from /system have the coredomain |
| # attribute |
| ret = "" |
| |
| for d in test_policy.alldomains: |
| domain = test_policy.alldomains[d] |
| if domain.fromSystem and domain.fromVendor: |
| ret += "The following domain is system and vendor: " + d + "\n" |
| |
| for domain in test_policy.alldomains.values(): |
| ret += domain.error |
| |
| violators = [] |
| for d in test_policy.alldomains: |
| domain = test_policy.alldomains[d] |
| if domain.fromSystem and "coredomain" not in domain.attributes: |
| violators.append(d); |
| if len(violators) > 0: |
| ret += "The following domain(s) must be associated with the " |
| ret += "\"coredomain\" attribute because they are executed off of " |
| ret += "/system:\n" |
| ret += " ".join(str(x) for x in sorted(violators)) + "\n" |
| |
| # verify that all domains launched form /vendor do not have the coredomain |
| # attribute |
| violators = [] |
| for d in test_policy.alldomains: |
| domain = test_policy.alldomains[d] |
| if domain.fromVendor and "coredomain" in domain.attributes: |
| violators.append(d) |
| if len(violators) > 0: |
| ret += "The following domains must not be associated with the " |
| ret += "\"coredomain\" attribute because they are executed off of " |
| ret += "/vendor or /system/vendor:\n" |
| ret += " ".join(str(x) for x in sorted(violators)) + "\n" |
| |
| return ret |
| |
| ### |
| # Make sure that any new public type introduced in the new policy that was not |
| # present in the old policy has been recorded in the mapping file. |
| def TestNoUnmappedNewTypes(test_policy): |
| newt = test_policy.alltypes - test_policy.oldalltypes |
| ret = "" |
| violators = [] |
| |
| for n in newt: |
| if n in test_policy.pubtypes and test_policy.compatMapping.rTypeattributesets.get(n) is None: |
| violators.append(n) |
| |
| if len(violators) > 0: |
| ret += "SELinux: The following public types were found added to the " |
| ret += "policy without an entry into the compatibility mapping file(s) " |
| ret += "found in private/compat/V.v/V.v[.ignore].cil, where V.v is the " |
| ret += "latest API level.\n" |
| ret += " ".join(str(x) for x in sorted(violators)) + "\n\n" |
| ret += "See examples of how to fix this:\n" |
| ret += "https://android-review.googlesource.com/c/platform/system/sepolicy/+/781036\n" |
| ret += "https://android-review.googlesource.com/c/platform/system/sepolicy/+/852612\n" |
| return ret |
| |
| ### |
| # Make sure that any public type removed in the current policy has its |
| # declaration added to the mapping file for use in non-platform policy |
| def TestNoUnmappedRmTypes(test_policy): |
| rmt = test_policy.oldalltypes - test_policy.alltypes |
| ret = "" |
| violators = [] |
| |
| for o in rmt: |
| if o in test_policy.compatMapping.pubtypes and not o in test_policy.compatMapping.types: |
| violators.append(o) |
| |
| if len(violators) > 0: |
| ret += "SELinux: The following formerly public types were removed from " |
| ret += "policy without a declaration in the compatibility mapping " |
| ret += "found in private/compat/V.v/V.v[.ignore].cil, where V.v is the " |
| ret += "latest API level.\n" |
| ret += " ".join(str(x) for x in sorted(violators)) + "\n\n" |
| ret += "See examples of how to fix this:\n" |
| ret += "https://android-review.googlesource.com/c/platform/system/sepolicy/+/822743\n" |
| return ret |
| |
| def TestTrebleCompatMapping(test_policy): |
| ret = TestNoUnmappedNewTypes(test_policy) |
| ret += TestNoUnmappedRmTypes(test_policy) |
| return ret |
| |
| def TestViolatorAttribute(test_policy, attribute): |
| ret = "" |
| if test_policy.FakeTreble: |
| return ret |
| |
| violators = test_policy.DomainsWithAttribute(attribute) |
| if len(violators) > 0: |
| ret += "SELinux: The following domains violate the Treble ban " |
| ret += "against use of the " + attribute + " attribute: " |
| ret += " ".join(str(x) for x in sorted(violators)) + "\n" |
| return ret |
| |
| def TestViolatorAttributes(test_policy): |
| ret = "" |
| ret += TestViolatorAttribute(test_policy, "socket_between_core_and_vendor_violators") |
| ret += TestViolatorAttribute(test_policy, "vendor_executes_system_violators") |
| return ret |
| |
| # TODO move this to sepolicy_tests |
| def TestCoreDataTypeViolations(test_policy): |
| return test_policy.pol.AssertPathTypesDoNotHaveAttr(["/data/vendor/", "/data/vendor_ce/", |
| "/data/vendor_de/"], [], "core_data_file_type") |
| |
| # TODO move this to sepolicy_tests |
| def TestIsolatedAttributeConsistency(test_policy): |
| permissionAllowList = { |
| # access given from technical_debt.cil |
| "codec2_config_prop" : ["file"], |
| "device_config_nnapi_native_prop":["file"], |
| "hal_allocator_default":["binder", "fd"], |
| "hal_codec2": ["binder", "fd"], |
| "hal_codec2_hwservice":["hwservice_manager"], |
| "hal_graphics_allocator": ["binder", "fd"], |
| "hal_graphics_allocator_service":["service_manager"], |
| "hal_graphics_allocator_hwservice":["hwservice_manager"], |
| "hal_graphics_allocator_server":["binder", "service_manager"], |
| "hal_graphics_mapper_hwservice":["hwservice_manager"], |
| "hal_neuralnetworks": ["binder", "fd"], |
| "hal_neuralnetworks_service": ["service_manager"], |
| "hal_neuralnetworks_hwservice":["hwservice_manager"], |
| "hal_omx_hwservice":["hwservice_manager"], |
| "hidl_allocator_hwservice":["hwservice_manager"], |
| "hidl_manager_hwservice":["hwservice_manager"], |
| "hidl_memory_hwservice":["hwservice_manager"], |
| "hidl_token_hwservice":["hwservice_manager"], |
| "hwservicemanager":["binder"], |
| "hwservicemanager_prop":["file"], |
| "mediacodec":["binder", "fd"], |
| "mediaswcodec":["binder", "fd"], |
| "media_variant_prop":["file"], |
| "nnapi_ext_deny_product_prop":["file"], |
| "servicemanager":["fd"], |
| "toolbox_exec": ["file"], |
| # extra types being granted to isolated_compute_app |
| "isolated_compute_allowed":["service_manager", "chr_file"], |
| } |
| |
| def resolveHalServerSubtype(target): |
| # permission given as a client in technical_debt.cil |
| hal_server_attributes = [ |
| "hal_codec2_server", |
| "hal_graphics_allocator_server", |
| "hal_neuralnetworks_server"] |
| |
| for attr in hal_server_attributes: |
| if target in test_policy.pol.QueryTypeAttribute(Type=attr, IsAttr=True): |
| return attr.rsplit("_", 1)[0] |
| return target |
| |
| def checkIsolatedComputeAllowed(tctx, tclass): |
| # check if the permission is in isolated_compute_allowed |
| allowedMemberTypes = test_policy.pol.QueryTypeAttribute(Type="isolated_compute_allowed_service", IsAttr=True) \ |
| .union(test_policy.pol.QueryTypeAttribute(Type="isolated_compute_allowed_device", IsAttr=True)) |
| return tctx in allowedMemberTypes and tclass in permissionAllowList["isolated_compute_allowed"] |
| |
| |
| def checkPermissions(permissions): |
| violated_permissions = [] |
| for perm in permissions: |
| tctx, tclass, p = perm.split(":") |
| tctx = resolveHalServerSubtype(tctx) |
| # check unwanted permissions |
| if not checkIsolatedComputeAllowed(tctx, tclass) and \ |
| ( tctx not in permissionAllowList \ |
| or tclass not in permissionAllowList[tctx] \ |
| or ( p == "write") \ |
| or ( p == "rw_file_perms") ): |
| violated_permissions += [perm] |
| return violated_permissions |
| |
| ret = "" |
| |
| isolatedMemberTypes = test_policy.pol.QueryTypeAttribute(Type="isolated_app_all", IsAttr=True) |
| baseRules = test_policy.pol.QueryExpandedTERule(scontext=["isolated_app"]) |
| basePermissionSet = set([":".join([rule.tctx, rule.tclass, perm]) |
| for rule in baseRules for perm in rule.perms]) |
| for subType in isolatedMemberTypes: |
| if subType == "isolated_app" : continue |
| currentTypeRule = test_policy.pol.QueryExpandedTERule(scontext=[subType]) |
| typePermissionSet = set([":".join([rule.tctx, rule.tclass, perm]) |
| for rule in currentTypeRule for perm in rule.perms |
| if not rule.tctx in [subType, subType + "_userfaultfd"]]) |
| deltaPermissionSet = typePermissionSet.difference(basePermissionSet) |
| violated_permissions = checkPermissions(list(deltaPermissionSet)) |
| for perm in violated_permissions: |
| ret += "allow %s %s:%s %s \n" % (subType, *perm.split(":")) |
| |
| if ret: |
| ret = ("Found prohibited permission granted for isolated like types. " + \ |
| "Please replace your allow statements that involve \"-isolated_app\" with " + \ |
| "\"-isolated_app_all\". Violations are shown as the following: \n") + ret |
| return ret |
| |
| ### |
| # extend OptionParser to allow the same option flag to be used multiple times. |
| # This is used to allow multiple file_contexts files and tests to be |
| # specified. |
| # |
| class MultipleOption(Option): |
| ACTIONS = Option.ACTIONS + ("extend",) |
| STORE_ACTIONS = Option.STORE_ACTIONS + ("extend",) |
| TYPED_ACTIONS = Option.TYPED_ACTIONS + ("extend",) |
| ALWAYS_TYPED_ACTIONS = Option.ALWAYS_TYPED_ACTIONS + ("extend",) |
| |
| def take_action(self, action, dest, opt, value, values, parser): |
| if action == "extend": |
| values.ensure_value(dest, []).append(value) |
| else: |
| Option.take_action(self, action, dest, opt, value, values, parser) |
| |
| Tests = {"CoredomainViolations": TestCoredomainViolations, |
| "CoreDatatypeViolations": TestCoreDataTypeViolations, |
| "TrebleCompatMapping": TestTrebleCompatMapping, |
| "ViolatorAttributes": TestViolatorAttributes, |
| "IsolatedAttributeConsistency": TestIsolatedAttributeConsistency} |
| |
| def do_main(libpath): |
| """ |
| Args: |
| libpath: string, path to libsepolwrap.so |
| """ |
| test_policy = TestPolicy() |
| |
| usage = "treble_sepolicy_tests " |
| usage += "-f nonplat_file_contexts -f plat_file_contexts " |
| usage += "-p curr_policy -b base_policy -o old_policy " |
| usage +="-m mapping file [--test test] [--help]" |
| parser = OptionParser(option_class=MultipleOption, usage=usage) |
| parser.add_option("-b", "--basepolicy", dest="basepolicy", metavar="FILE") |
| parser.add_option("-u", "--base-pub-policy", dest="base_pub_policy", |
| metavar="FILE") |
| parser.add_option("-f", "--file_contexts", dest="file_contexts", |
| metavar="FILE", action="extend", type="string") |
| parser.add_option("-m", "--mapping", dest="mapping", metavar="FILE") |
| parser.add_option("-o", "--oldpolicy", dest="oldpolicy", metavar="FILE") |
| parser.add_option("-p", "--policy", dest="policy", metavar="FILE") |
| parser.add_option("-t", "--test", dest="tests", action="extend", |
| help="Test options include "+str(Tests)) |
| parser.add_option("--fake-treble", action="store_true", dest="faketreble", |
| default=False) |
| |
| (options, args) = parser.parse_args() |
| |
| if not options.policy: |
| sys.exit("Must specify current monolithic policy file\n" + parser.usage) |
| if not os.path.exists(options.policy): |
| sys.exit("Error: policy file " + options.policy + " does not exist\n" |
| + parser.usage) |
| if not options.file_contexts: |
| sys.exit("Error: Must specify file_contexts file(s)\n" + parser.usage) |
| for f in options.file_contexts: |
| if not os.path.exists(f): |
| sys.exit("Error: File_contexts file " + f + " does not exist\n" + |
| parser.usage) |
| |
| # Mapping files and public platform policy are only necessary for the |
| # TrebleCompatMapping test. |
| if options.tests is None or options.tests == "TrebleCompatMapping": |
| if not options.basepolicy: |
| sys.exit("Must specify the current platform-only policy file\n" |
| + parser.usage) |
| if not options.mapping: |
| sys.exit("Must specify a compatibility mapping file\n" |
| + parser.usage) |
| if not options.oldpolicy: |
| sys.exit("Must specify the previous monolithic policy file\n" |
| + parser.usage) |
| if not options.base_pub_policy: |
| sys.exit("Must specify the current platform-only public policy " |
| + ".cil file\n" + parser.usage) |
| basepol = policy.Policy(options.basepolicy, None, libpath) |
| oldpol = policy.Policy(options.oldpolicy, None, libpath) |
| mapping = mini_parser.MiniCilParser(options.mapping) |
| pubpol = mini_parser.MiniCilParser(options.base_pub_policy) |
| test_policy.compatSetup(basepol, oldpol, mapping, pubpol.types) |
| |
| if options.faketreble: |
| test_policy.FakeTreble = True |
| |
| pol = policy.Policy(options.policy, options.file_contexts, libpath) |
| test_policy.setup(pol) |
| |
| if DEBUG: |
| test_policy.PrintScontexts() |
| |
| results = "" |
| # If an individual test is not specified, run all tests. |
| if options.tests is None: |
| for t in Tests.values(): |
| results += t(test_policy) |
| else: |
| for tn in options.tests: |
| t = Tests.get(tn) |
| if t: |
| results += t(test_policy) |
| else: |
| err = "Error: unknown test: " + tn + "\n" |
| err += "Available tests:\n" |
| for tn in Tests.keys(): |
| err += tn + "\n" |
| sys.exit(err) |
| |
| if len(results) > 0: |
| sys.exit(results) |
| |
| if __name__ == '__main__': |
| temp_dir = tempfile.mkdtemp() |
| try: |
| libname = "libsepolwrap" + SHARED_LIB_EXTENSION |
| libpath = os.path.join(temp_dir, libname) |
| with open(libpath, "wb") as f: |
| blob = pkgutil.get_data("treble_sepolicy_tests", libname) |
| if not blob: |
| sys.exit("Error: libsepolwrap does not exist. Is this binary corrupted?\n") |
| f.write(blob) |
| do_main(libpath) |
| finally: |
| shutil.rmtree(temp_dir) |