/* * Copyright (C) 2016 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. */ #define LOG_TAG "ServiceManagement" #include <android/dlext.h> #include <condition_variable> #include <dlfcn.h> #include <dirent.h> #include <fstream> #include <pthread.h> #include <unistd.h> #include <mutex> #include <regex> #include <set> #include <hidl/HidlBinderSupport.h> #include <hidl/HidlInternal.h> #include <hidl/HidlTransportUtils.h> #include <hidl/ServiceManagement.h> #include <hidl/Status.h> #include <android-base/logging.h> #include <android-base/properties.h> #include <android-base/stringprintf.h> #include <hwbinder/IPCThreadState.h> #include <hwbinder/Parcel.h> #include <vndksupport/linker.h> #include <android/hidl/manager/1.1/IServiceManager.h> #include <android/hidl/manager/1.1/BpHwServiceManager.h> #include <android/hidl/manager/1.1/BnHwServiceManager.h> #define RE_COMPONENT "[a-zA-Z_][a-zA-Z_0-9]*" #define RE_PATH RE_COMPONENT "(?:[.]" RE_COMPONENT ")*" static const std::regex gLibraryFileNamePattern("(" RE_PATH "@[0-9]+[.][0-9]+)-impl(.*?).so"); using android::base::WaitForProperty; using IServiceManager1_0 = android::hidl::manager::V1_0::IServiceManager; using IServiceManager1_1 = android::hidl::manager::V1_1::IServiceManager; using android::hidl::manager::V1_0::IServiceNotification; using android::hidl::manager::V1_1::BpHwServiceManager; using android::hidl::manager::V1_1::BnHwServiceManager; namespace android { namespace hardware { namespace details { extern Mutex gDefaultServiceManagerLock; extern sp<android::hidl::manager::V1_1::IServiceManager> gDefaultServiceManager; } // namespace details static const char* kHwServicemanagerReadyProperty = "hwservicemanager.ready"; void waitForHwServiceManager() { using std::literals::chrono_literals::operator""s; while (!WaitForProperty(kHwServicemanagerReadyProperty, "true", 1s)) { LOG(WARNING) << "Waited for hwservicemanager.ready for a second, waiting another..."; } } bool endsWith(const std::string &in, const std::string &suffix) { return in.size() >= suffix.size() && in.substr(in.size() - suffix.size()) == suffix; } bool startsWith(const std::string &in, const std::string &prefix) { return in.size() >= prefix.size() && in.substr(0, prefix.size()) == prefix; } std::string binaryName() { std::ifstream ifs("/proc/self/cmdline"); std::string cmdline; if (!ifs.is_open()) { return ""; } ifs >> cmdline; size_t idx = cmdline.rfind('/'); if (idx != std::string::npos) { cmdline = cmdline.substr(idx + 1); } return cmdline; } std::string packageWithoutVersion(const std::string& packageAndVersion) { size_t at = packageAndVersion.find('@'); if (at == std::string::npos) return packageAndVersion; return packageAndVersion.substr(0, at); } void tryShortenProcessName(const std::string& packageAndVersion) { const static std::string kTasks = "/proc/self/task/"; // make sure that this binary name is in the same package std::string processName = binaryName(); // e.x. android.hardware.foo is this package if (!startsWith(packageWithoutVersion(processName), packageWithoutVersion(packageAndVersion))) { return; } // e.x. android.hardware.module.foo@1.2 -> foo@1.2 size_t lastDot = packageAndVersion.rfind('.'); if (lastDot == std::string::npos) return; size_t secondDot = packageAndVersion.rfind('.', lastDot - 1); if (secondDot == std::string::npos) return; std::string newName = processName.substr(secondDot + 1, std::string::npos); ALOGI("Removing namespace from process name %s to %s.", processName.c_str(), newName.c_str()); std::unique_ptr<DIR, decltype(&closedir)> dir(opendir(kTasks.c_str()), closedir); if (dir == nullptr) return; dirent* dp; while ((dp = readdir(dir.get())) != nullptr) { if (dp->d_type != DT_DIR) continue; if (dp->d_name[0] == '.') continue; std::fstream fs(kTasks + dp->d_name + "/comm"); if (!fs.is_open()) { ALOGI("Could not rename process, failed read comm for %s.", dp->d_name); continue; } std::string oldComm; fs >> oldComm; // don't rename if it already has an explicit name if (startsWith(packageAndVersion, oldComm)) { fs.seekg(0, fs.beg); fs << newName; } } } namespace details { void onRegistration(const std::string &packageName, const std::string& /* interfaceName */, const std::string& /* instanceName */) { tryShortenProcessName(packageName); } } // details sp<IServiceManager1_0> defaultServiceManager() { return defaultServiceManager1_1(); } sp<IServiceManager1_1> defaultServiceManager1_1() { { AutoMutex _l(details::gDefaultServiceManagerLock); if (details::gDefaultServiceManager != nullptr) { return details::gDefaultServiceManager; } if (access("/dev/hwbinder", F_OK|R_OK|W_OK) != 0) { // HwBinder not available on this device or not accessible to // this process. return nullptr; } waitForHwServiceManager(); while (details::gDefaultServiceManager == nullptr) { details::gDefaultServiceManager = fromBinder<IServiceManager1_1, BpHwServiceManager, BnHwServiceManager>( ProcessState::self()->getContextObject(nullptr)); if (details::gDefaultServiceManager == nullptr) { LOG(ERROR) << "Waited for hwservicemanager, but got nullptr."; sleep(1); } } } return details::gDefaultServiceManager; } std::vector<std::string> search(const std::string &path, const std::string &prefix, const std::string &suffix) { std::unique_ptr<DIR, decltype(&closedir)> dir(opendir(path.c_str()), closedir); if (!dir) return {}; std::vector<std::string> results{}; dirent* dp; while ((dp = readdir(dir.get())) != nullptr) { std::string name = dp->d_name; if (startsWith(name, prefix) && endsWith(name, suffix)) { results.push_back(name); } } return results; } bool matchPackageName(const std::string& lib, std::string* matchedName, std::string* implName) { std::smatch match; if (std::regex_match(lib, match, gLibraryFileNamePattern)) { *matchedName = match.str(1) + "::I*"; *implName = match.str(2); return true; } return false; } static void registerReference(const hidl_string &interfaceName, const hidl_string &instanceName) { sp<IServiceManager1_0> binderizedManager = defaultServiceManager(); if (binderizedManager == nullptr) { LOG(WARNING) << "Could not registerReference for " << interfaceName << "/" << instanceName << ": null binderized manager."; return; } auto ret = binderizedManager->registerPassthroughClient(interfaceName, instanceName); if (!ret.isOk()) { LOG(WARNING) << "Could not registerReference for " << interfaceName << "/" << instanceName << ": " << ret.description(); return; } LOG(VERBOSE) << "Successfully registerReference for " << interfaceName << "/" << instanceName; } using InstanceDebugInfo = hidl::manager::V1_0::IServiceManager::InstanceDebugInfo; static inline void fetchPidsForPassthroughLibraries( std::map<std::string, InstanceDebugInfo>* infos) { static const std::string proc = "/proc/"; std::map<std::string, std::set<pid_t>> pids; std::unique_ptr<DIR, decltype(&closedir)> dir(opendir(proc.c_str()), closedir); if (!dir) return; dirent* dp; while ((dp = readdir(dir.get())) != nullptr) { pid_t pid = strtoll(dp->d_name, nullptr, 0); if (pid == 0) continue; std::string mapsPath = proc + dp->d_name + "/maps"; std::ifstream ifs{mapsPath}; if (!ifs.is_open()) continue; for (std::string line; std::getline(ifs, line);) { // The last token of line should look like // vendor/lib64/hw/android.hardware.foo@1.0-impl-extra.so // Use some simple filters to ignore bad lines before extracting libFileName // and checking the key in info to make parsing faster. if (line.back() != 'o') continue; if (line.rfind('@') == std::string::npos) continue; auto spacePos = line.rfind(' '); if (spacePos == std::string::npos) continue; auto libFileName = line.substr(spacePos + 1); auto it = infos->find(libFileName); if (it == infos->end()) continue; pids[libFileName].insert(pid); } } for (auto& pair : *infos) { pair.second.clientPids = std::vector<pid_t>{pids[pair.first].begin(), pids[pair.first].end()}; } } struct PassthroughServiceManager : IServiceManager1_1 { static void openLibs( const std::string& fqName, const std::function<bool /* continue */ (void* /* handle */, const std::string& /* lib */, const std::string& /* sym */)>& eachLib) { //fqName looks like android.hardware.foo@1.0::IFoo size_t idx = fqName.find("::"); if (idx == std::string::npos || idx + strlen("::") + 1 >= fqName.size()) { LOG(ERROR) << "Invalid interface name passthrough lookup: " << fqName; return; } std::string packageAndVersion = fqName.substr(0, idx); std::string ifaceName = fqName.substr(idx + strlen("::")); const std::string prefix = packageAndVersion + "-impl"; const std::string sym = "HIDL_FETCH_" + ifaceName; constexpr int dlMode = RTLD_LAZY; void* handle = nullptr; dlerror(); // clear static std::string halLibPathVndkSp = android::base::StringPrintf( HAL_LIBRARY_PATH_VNDK_SP_FOR_VERSION, details::getVndkVersionStr().c_str()); std::vector<std::string> paths = {HAL_LIBRARY_PATH_ODM, HAL_LIBRARY_PATH_VENDOR, halLibPathVndkSp, HAL_LIBRARY_PATH_SYSTEM}; #ifdef LIBHIDL_TARGET_DEBUGGABLE const char* env = std::getenv("TREBLE_TESTING_OVERRIDE"); const bool trebleTestingOverride = env && !strcmp(env, "true"); if (trebleTestingOverride) { // Load HAL implementations that are statically linked handle = dlopen(nullptr, dlMode); if (handle == nullptr) { const char* error = dlerror(); LOG(ERROR) << "Failed to dlopen self: " << (error == nullptr ? "unknown error" : error); } else if (!eachLib(handle, "SELF", sym)) { return; } const char* vtsRootPath = std::getenv("VTS_ROOT_PATH"); if (vtsRootPath && strlen(vtsRootPath) > 0) { const std::string halLibraryPathVtsOverride = std::string(vtsRootPath) + HAL_LIBRARY_PATH_SYSTEM; paths.insert(paths.begin(), halLibraryPathVtsOverride); } } #endif for (const std::string& path : paths) { std::vector<std::string> libs = search(path, prefix, ".so"); for (const std::string &lib : libs) { const std::string fullPath = path + lib; if (path == HAL_LIBRARY_PATH_SYSTEM) { handle = dlopen(fullPath.c_str(), dlMode); } else { handle = android_load_sphal_library(fullPath.c_str(), dlMode); } if (handle == nullptr) { const char* error = dlerror(); LOG(ERROR) << "Failed to dlopen " << lib << ": " << (error == nullptr ? "unknown error" : error); continue; } if (!eachLib(handle, lib, sym)) { return; } } } } Return<sp<IBase>> get(const hidl_string& fqName, const hidl_string& name) override { sp<IBase> ret = nullptr; openLibs(fqName, [&](void* handle, const std::string &lib, const std::string &sym) { IBase* (*generator)(const char* name); *(void **)(&generator) = dlsym(handle, sym.c_str()); if(!generator) { const char* error = dlerror(); LOG(ERROR) << "Passthrough lookup opened " << lib << " but could not find symbol " << sym << ": " << (error == nullptr ? "unknown error" : error); dlclose(handle); return true; } ret = (*generator)(name.c_str()); if (ret == nullptr) { dlclose(handle); return true; // this module doesn't provide this instance name } // Actual fqname might be a subclass. // This assumption is tested in vts_treble_vintf_test using ::android::hardware::details::getDescriptor; std::string actualFqName = getDescriptor(ret.get()); CHECK(actualFqName.size() > 0); registerReference(actualFqName, name); return false; }); return ret; } Return<bool> add(const hidl_string& /* name */, const sp<IBase>& /* service */) override { LOG(FATAL) << "Cannot register services with passthrough service manager."; return false; } Return<Transport> getTransport(const hidl_string& /* fqName */, const hidl_string& /* name */) { LOG(FATAL) << "Cannot getTransport with passthrough service manager."; return Transport::EMPTY; } Return<void> list(list_cb /* _hidl_cb */) override { LOG(FATAL) << "Cannot list services with passthrough service manager."; return Void(); } Return<void> listByInterface(const hidl_string& /* fqInstanceName */, listByInterface_cb /* _hidl_cb */) override { // TODO: add this functionality LOG(FATAL) << "Cannot list services with passthrough service manager."; return Void(); } Return<bool> registerForNotifications(const hidl_string& /* fqName */, const hidl_string& /* name */, const sp<IServiceNotification>& /* callback */) override { // This makes no sense. LOG(FATAL) << "Cannot register for notifications with passthrough service manager."; return false; } Return<void> debugDump(debugDump_cb _hidl_cb) override { using Arch = ::android::hidl::base::V1_0::DebugInfo::Architecture; using std::literals::string_literals::operator""s; static std::string halLibPathVndkSp64 = android::base::StringPrintf( HAL_LIBRARY_PATH_VNDK_SP_64BIT_FOR_VERSION, details::getVndkVersionStr().c_str()); static std::string halLibPathVndkSp32 = android::base::StringPrintf( HAL_LIBRARY_PATH_VNDK_SP_32BIT_FOR_VERSION, details::getVndkVersionStr().c_str()); static std::vector<std::pair<Arch, std::vector<const char*>>> sAllPaths{ {Arch::IS_64BIT, {HAL_LIBRARY_PATH_ODM_64BIT, HAL_LIBRARY_PATH_VENDOR_64BIT, halLibPathVndkSp64.c_str(), HAL_LIBRARY_PATH_SYSTEM_64BIT}}, {Arch::IS_32BIT, {HAL_LIBRARY_PATH_ODM_32BIT, HAL_LIBRARY_PATH_VENDOR_32BIT, halLibPathVndkSp32.c_str(), HAL_LIBRARY_PATH_SYSTEM_32BIT}}}; std::map<std::string, InstanceDebugInfo> map; for (const auto &pair : sAllPaths) { Arch arch = pair.first; for (const auto &path : pair.second) { std::vector<std::string> libs = search(path, "", ".so"); for (const std::string &lib : libs) { std::string matchedName; std::string implName; if (matchPackageName(lib, &matchedName, &implName)) { std::string instanceName{"* ("s + path + ")"s}; if (!implName.empty()) instanceName += " ("s + implName + ")"s; map.emplace(path + lib, InstanceDebugInfo{.interfaceName = matchedName, .instanceName = instanceName, .clientPids = {}, .arch = arch}); } } } } fetchPidsForPassthroughLibraries(&map); hidl_vec<InstanceDebugInfo> vec; vec.resize(map.size()); size_t idx = 0; for (auto&& pair : map) { vec[idx++] = std::move(pair.second); } _hidl_cb(vec); return Void(); } Return<void> registerPassthroughClient(const hidl_string &, const hidl_string &) override { // This makes no sense. LOG(FATAL) << "Cannot call registerPassthroughClient on passthrough service manager. " << "Call it on defaultServiceManager() instead."; return Void(); } Return<bool> unregisterForNotifications(const hidl_string& /* fqName */, const hidl_string& /* name */, const sp<IServiceNotification>& /* callback */) override { // This makes no sense. LOG(FATAL) << "Cannot unregister for notifications with passthrough service manager."; return false; } }; sp<IServiceManager1_0> getPassthroughServiceManager() { return getPassthroughServiceManager1_1(); } sp<IServiceManager1_1> getPassthroughServiceManager1_1() { static sp<PassthroughServiceManager> manager(new PassthroughServiceManager()); return manager; } namespace details { void preloadPassthroughService(const std::string &descriptor) { PassthroughServiceManager::openLibs(descriptor, [&](void* /* handle */, const std::string& /* lib */, const std::string& /* sym */) { // do nothing return true; // open all libs }); } struct Waiter : IServiceNotification { Waiter(const std::string& interface, const std::string& instanceName, const sp<IServiceManager1_1>& sm) : mInterfaceName(interface), mInstanceName(instanceName), mSm(sm) { } void onFirstRef() override { // If this process only has one binder thread, and we're calling wait() from // that thread, it will block forever because we hung up the one and only // binder thread on a condition variable that can only be notified by an // incoming binder call. if (IPCThreadState::self()->isOnlyBinderThread()) { LOG(WARNING) << "Can't efficiently wait for " << mInterfaceName << "/" << mInstanceName << ", because we are called from " << "the only binder thread in this process."; return; } Return<bool> ret = mSm->registerForNotifications(mInterfaceName, mInstanceName, this); if (!ret.isOk()) { LOG(ERROR) << "Transport error, " << ret.description() << ", during notification registration for " << mInterfaceName << "/" << mInstanceName << "."; return; } if (!ret) { LOG(ERROR) << "Could not register for notifications for " << mInterfaceName << "/" << mInstanceName << "."; return; } mRegisteredForNotifications = true; } ~Waiter() { if (!mDoneCalled) { LOG(FATAL) << "Waiter still registered for notifications, call done() before dropping ref!"; } } Return<void> onRegistration(const hidl_string& /* fqName */, const hidl_string& /* name */, bool /* preexisting */) override { std::unique_lock<std::mutex> lock(mMutex); if (mRegistered) { return Void(); } mRegistered = true; lock.unlock(); mCondition.notify_one(); return Void(); } void wait() { using std::literals::chrono_literals::operator""s; if (!mRegisteredForNotifications) { // As an alternative, just sleep for a second and return LOG(WARNING) << "Waiting one second for " << mInterfaceName << "/" << mInstanceName; sleep(1); return; } std::unique_lock<std::mutex> lock(mMutex); while(true) { mCondition.wait_for(lock, 1s, [this]{ return mRegistered; }); if (mRegistered) { break; } LOG(WARNING) << "Waited one second for " << mInterfaceName << "/" << mInstanceName << ". Waiting another..."; } } // Be careful when using this; after calling reset(), you must always try to retrieve // the corresponding service before blocking on the waiter; otherwise, you might run // into a race-condition where the service has just (re-)registered, you clear the state // here, and subsequently calling waiter->wait() will block forever. void reset() { std::unique_lock<std::mutex> lock(mMutex); mRegistered = false; } // done() must be called before dropping the last strong ref to the Waiter, to make // sure we can properly unregister with hwservicemanager. void done() { if (mRegisteredForNotifications) { if (!mSm->unregisterForNotifications(mInterfaceName, mInstanceName, this) .withDefault(false)) { LOG(ERROR) << "Could not unregister service notification for " << mInterfaceName << "/" << mInstanceName << "."; } else { mRegisteredForNotifications = false; } } mDoneCalled = true; } private: const std::string mInterfaceName; const std::string mInstanceName; const sp<IServiceManager1_1>& mSm; std::mutex mMutex; std::condition_variable mCondition; bool mRegistered = false; bool mRegisteredForNotifications = false; bool mDoneCalled = false; }; void waitForHwService( const std::string &interface, const std::string &instanceName) { sp<Waiter> waiter = new Waiter(interface, instanceName, defaultServiceManager1_1()); waiter->wait(); waiter->done(); } // Prints relevant error/warning messages for error return values from // details::canCastInterface(), both transaction errors (!castReturn.isOk()) // as well as actual cast failures (castReturn.isOk() && castReturn = false). // Returns 'true' if the error is non-fatal and it's useful to retry bool handleCastError(const Return<bool>& castReturn, const std::string& descriptor, const std::string& instance) { if (castReturn.isOk()) { if (castReturn) { details::logAlwaysFatal("Successful cast value passed into handleCastError."); } // This should never happen, and there's not really a point in retrying. ALOGE("getService: received incompatible service (bug in hwservicemanager?) for " "%s/%s.", descriptor.c_str(), instance.c_str()); return false; } if (castReturn.isDeadObject()) { ALOGW("getService: found dead hwbinder service for %s/%s.", descriptor.c_str(), instance.c_str()); return true; } // This can happen due to: // 1) No SELinux permissions // 2) Other transaction failure (no buffer space, kernel error) // The first isn't recoverable, but the second is. // Since we can't yet differentiate between the two, and clients depend // on us not blocking in case 1), treat this as a fatal error for now. ALOGW("getService: unable to call into hwbinder service for %s/%s.", descriptor.c_str(), instance.c_str()); return false; } sp<::android::hidl::base::V1_0::IBase> getRawServiceInternal(const std::string& descriptor, const std::string& instance, bool retry, bool getStub) { using Transport = ::android::hidl::manager::V1_0::IServiceManager::Transport; using ::android::hidl::base::V1_0::IBase; using ::android::hidl::manager::V1_0::IServiceManager; sp<Waiter> waiter; const sp<IServiceManager1_1> sm = defaultServiceManager1_1(); if (sm == nullptr) { ALOGE("getService: defaultServiceManager() is null"); return nullptr; } Return<Transport> transportRet = sm->getTransport(descriptor, instance); if (!transportRet.isOk()) { ALOGE("getService: defaultServiceManager()->getTransport returns %s", transportRet.description().c_str()); return nullptr; } Transport transport = transportRet; const bool vintfHwbinder = (transport == Transport::HWBINDER); const bool vintfPassthru = (transport == Transport::PASSTHROUGH); #ifdef ENFORCE_VINTF_MANIFEST #ifdef LIBHIDL_TARGET_DEBUGGABLE const char* env = std::getenv("TREBLE_TESTING_OVERRIDE"); const bool trebleTestingOverride = env && !strcmp(env, "true"); const bool vintfLegacy = (transport == Transport::EMPTY) && trebleTestingOverride; #else // ENFORCE_VINTF_MANIFEST but not LIBHIDL_TARGET_DEBUGGABLE const bool trebleTestingOverride = false; const bool vintfLegacy = false; #endif // LIBHIDL_TARGET_DEBUGGABLE #else // not ENFORCE_VINTF_MANIFEST const char* env = std::getenv("TREBLE_TESTING_OVERRIDE"); const bool trebleTestingOverride = env && !strcmp(env, "true"); const bool vintfLegacy = (transport == Transport::EMPTY); #endif // ENFORCE_VINTF_MANIFEST for (int tries = 0; !getStub && (vintfHwbinder || vintfLegacy); tries++) { if (waiter == nullptr && tries > 0) { waiter = new Waiter(descriptor, instance, sm); } if (waiter != nullptr) { waiter->reset(); // don't reorder this -- see comments on reset() } Return<sp<IBase>> ret = sm->get(descriptor, instance); if (!ret.isOk()) { ALOGE("getService: defaultServiceManager()->get returns %s for %s/%s.", ret.description().c_str(), descriptor.c_str(), instance.c_str()); break; } sp<IBase> base = ret; if (base != nullptr) { Return<bool> canCastRet = details::canCastInterface(base.get(), descriptor.c_str(), true /* emitError */); if (canCastRet.isOk() && canCastRet) { if (waiter != nullptr) { waiter->done(); } return base; // still needs to be wrapped by Bp class. } if (!handleCastError(canCastRet, descriptor, instance)) break; } // In case of legacy or we were not asked to retry, don't. if (vintfLegacy || !retry) break; if (waiter != nullptr) { ALOGI("getService: Trying again for %s/%s...", descriptor.c_str(), instance.c_str()); waiter->wait(); } } if (waiter != nullptr) { waiter->done(); } if (getStub || vintfPassthru || vintfLegacy) { const sp<IServiceManager> pm = getPassthroughServiceManager(); if (pm != nullptr) { sp<IBase> base = pm->get(descriptor, instance).withDefault(nullptr); if (!getStub || trebleTestingOverride) { base = wrapPassthrough(base); } return base; } } return nullptr; } }; // namespace details }; // namespace hardware }; // namespace android