Move libnative{bridge,loader} to art/
This change moves system/core/libnative{bridge,loader} under art/.
Bug: 137364733
Test: m
Change-Id: I9be7333d00fcd3f36cd80520e50a30ea840187ad
diff --git a/libnativebridge/native_bridge.cc b/libnativebridge/native_bridge.cc
new file mode 100644
index 0000000..9adba9a
--- /dev/null
+++ b/libnativebridge/native_bridge.cc
@@ -0,0 +1,646 @@
+/*
+ * Copyright (C) 2014 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 "nativebridge"
+
+#include "nativebridge/native_bridge.h"
+
+#include <dlfcn.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include <cstring>
+
+#include <android-base/macros.h>
+#include <log/log.h>
+
+namespace android {
+
+#ifdef __APPLE__
+template <typename T>
+void UNUSED(const T&) {}
+#endif
+
+extern "C" {
+
+// Environment values required by the apps running with native bridge.
+struct NativeBridgeRuntimeValues {
+ const char* os_arch;
+ const char* cpu_abi;
+ const char* cpu_abi2;
+ const char* *supported_abis;
+ int32_t abi_count;
+};
+
+// The symbol name exposed by native-bridge with the type of NativeBridgeCallbacks.
+static constexpr const char* kNativeBridgeInterfaceSymbol = "NativeBridgeItf";
+
+enum class NativeBridgeState {
+ kNotSetup, // Initial state.
+ kOpened, // After successful dlopen.
+ kPreInitialized, // After successful pre-initialization.
+ kInitialized, // After successful initialization.
+ kClosed // Closed or errors.
+};
+
+static constexpr const char* kNotSetupString = "kNotSetup";
+static constexpr const char* kOpenedString = "kOpened";
+static constexpr const char* kPreInitializedString = "kPreInitialized";
+static constexpr const char* kInitializedString = "kInitialized";
+static constexpr const char* kClosedString = "kClosed";
+
+static const char* GetNativeBridgeStateString(NativeBridgeState state) {
+ switch (state) {
+ case NativeBridgeState::kNotSetup:
+ return kNotSetupString;
+
+ case NativeBridgeState::kOpened:
+ return kOpenedString;
+
+ case NativeBridgeState::kPreInitialized:
+ return kPreInitializedString;
+
+ case NativeBridgeState::kInitialized:
+ return kInitializedString;
+
+ case NativeBridgeState::kClosed:
+ return kClosedString;
+ }
+}
+
+// Current state of the native bridge.
+static NativeBridgeState state = NativeBridgeState::kNotSetup;
+
+// The version of NativeBridge implementation.
+// Different Nativebridge interface needs the service of different version of
+// Nativebridge implementation.
+// Used by isCompatibleWith() which is introduced in v2.
+enum NativeBridgeImplementationVersion {
+ // first version, not used.
+ DEFAULT_VERSION = 1,
+ // The version which signal semantic is introduced.
+ SIGNAL_VERSION = 2,
+ // The version which namespace semantic is introduced.
+ NAMESPACE_VERSION = 3,
+ // The version with vendor namespaces
+ VENDOR_NAMESPACE_VERSION = 4,
+ // The version with runtime namespaces
+ RUNTIME_NAMESPACE_VERSION = 5,
+};
+
+// Whether we had an error at some point.
+static bool had_error = false;
+
+// Handle of the loaded library.
+static void* native_bridge_handle = nullptr;
+// Pointer to the callbacks. Available as soon as LoadNativeBridge succeeds, but only initialized
+// later.
+static const NativeBridgeCallbacks* callbacks = nullptr;
+// Callbacks provided by the environment to the bridge. Passed to LoadNativeBridge.
+static const NativeBridgeRuntimeCallbacks* runtime_callbacks = nullptr;
+
+// The app's code cache directory.
+static char* app_code_cache_dir = nullptr;
+
+// Code cache directory (relative to the application private directory)
+// Ideally we'd like to call into framework to retrieve this name. However that's considered an
+// implementation detail and will require either hacks or consistent refactorings. We compromise
+// and hard code the directory name again here.
+static constexpr const char* kCodeCacheDir = "code_cache";
+
+// Characters allowed in a native bridge filename. The first character must
+// be in [a-zA-Z] (expected 'l' for "libx"). The rest must be in [a-zA-Z0-9._-].
+static bool CharacterAllowed(char c, bool first) {
+ if (first) {
+ return ('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z');
+ } else {
+ return ('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') || ('0' <= c && c <= '9') ||
+ (c == '.') || (c == '_') || (c == '-');
+ }
+}
+
+static void ReleaseAppCodeCacheDir() {
+ if (app_code_cache_dir != nullptr) {
+ delete[] app_code_cache_dir;
+ app_code_cache_dir = nullptr;
+ }
+}
+
+// We only allow simple names for the library. It is supposed to be a file in
+// /system/lib or /vendor/lib. Only allow a small range of characters, that is
+// names consisting of [a-zA-Z0-9._-] and starting with [a-zA-Z].
+bool NativeBridgeNameAcceptable(const char* nb_library_filename) {
+ const char* ptr = nb_library_filename;
+ if (*ptr == 0) {
+ // Emptry string. Allowed, means no native bridge.
+ return true;
+ } else {
+ // First character must be [a-zA-Z].
+ if (!CharacterAllowed(*ptr, true)) {
+ // Found an invalid fist character, don't accept.
+ ALOGE("Native bridge library %s has been rejected for first character %c",
+ nb_library_filename,
+ *ptr);
+ return false;
+ } else {
+ // For the rest, be more liberal.
+ ptr++;
+ while (*ptr != 0) {
+ if (!CharacterAllowed(*ptr, false)) {
+ // Found an invalid character, don't accept.
+ ALOGE("Native bridge library %s has been rejected for %c", nb_library_filename, *ptr);
+ return false;
+ }
+ ptr++;
+ }
+ }
+ return true;
+ }
+}
+
+// The policy of invoking Nativebridge changed in v3 with/without namespace.
+// Suggest Nativebridge implementation not maintain backward-compatible.
+static bool isCompatibleWith(const uint32_t version) {
+ // Libnativebridge is now designed to be forward-compatible. So only "0" is an unsupported
+ // version.
+ if (callbacks == nullptr || callbacks->version == 0 || version == 0) {
+ return false;
+ }
+
+ // If this is a v2+ bridge, it may not be forwards- or backwards-compatible. Check.
+ if (callbacks->version >= SIGNAL_VERSION) {
+ return callbacks->isCompatibleWith(version);
+ }
+
+ return true;
+}
+
+static void CloseNativeBridge(bool with_error) {
+ state = NativeBridgeState::kClosed;
+ had_error |= with_error;
+ ReleaseAppCodeCacheDir();
+}
+
+bool LoadNativeBridge(const char* nb_library_filename,
+ const NativeBridgeRuntimeCallbacks* runtime_cbs) {
+ // We expect only one place that calls LoadNativeBridge: Runtime::Init. At that point we are not
+ // multi-threaded, so we do not need locking here.
+
+ if (state != NativeBridgeState::kNotSetup) {
+ // Setup has been called before. Ignore this call.
+ if (nb_library_filename != nullptr) { // Avoids some log-spam for dalvikvm.
+ ALOGW("Called LoadNativeBridge for an already set up native bridge. State is %s.",
+ GetNativeBridgeStateString(state));
+ }
+ // Note: counts as an error, even though the bridge may be functional.
+ had_error = true;
+ return false;
+ }
+
+ if (nb_library_filename == nullptr || *nb_library_filename == 0) {
+ CloseNativeBridge(false);
+ return false;
+ } else {
+ if (!NativeBridgeNameAcceptable(nb_library_filename)) {
+ CloseNativeBridge(true);
+ } else {
+ // Try to open the library.
+ void* handle = dlopen(nb_library_filename, RTLD_LAZY);
+ if (handle != nullptr) {
+ callbacks = reinterpret_cast<NativeBridgeCallbacks*>(dlsym(handle,
+ kNativeBridgeInterfaceSymbol));
+ if (callbacks != nullptr) {
+ if (isCompatibleWith(NAMESPACE_VERSION)) {
+ // Store the handle for later.
+ native_bridge_handle = handle;
+ } else {
+ callbacks = nullptr;
+ dlclose(handle);
+ ALOGW("Unsupported native bridge interface.");
+ }
+ } else {
+ dlclose(handle);
+ }
+ }
+
+ // Two failure conditions: could not find library (dlopen failed), or could not find native
+ // bridge interface (dlsym failed). Both are an error and close the native bridge.
+ if (callbacks == nullptr) {
+ CloseNativeBridge(true);
+ } else {
+ runtime_callbacks = runtime_cbs;
+ state = NativeBridgeState::kOpened;
+ }
+ }
+ return state == NativeBridgeState::kOpened;
+ }
+}
+
+bool NeedsNativeBridge(const char* instruction_set) {
+ if (instruction_set == nullptr) {
+ ALOGE("Null instruction set in NeedsNativeBridge.");
+ return false;
+ }
+ return strncmp(instruction_set, ABI_STRING, strlen(ABI_STRING) + 1) != 0;
+}
+
+bool PreInitializeNativeBridge(const char* app_data_dir_in, const char* instruction_set) {
+ if (state != NativeBridgeState::kOpened) {
+ ALOGE("Invalid state: native bridge is expected to be opened.");
+ CloseNativeBridge(true);
+ return false;
+ }
+
+ if (app_data_dir_in == nullptr) {
+ ALOGE("Application private directory cannot be null.");
+ CloseNativeBridge(true);
+ return false;
+ }
+
+ // Create the path to the application code cache directory.
+ // The memory will be release after Initialization or when the native bridge is closed.
+ const size_t len = strlen(app_data_dir_in) + strlen(kCodeCacheDir) + 2; // '\0' + '/'
+ app_code_cache_dir = new char[len];
+ snprintf(app_code_cache_dir, len, "%s/%s", app_data_dir_in, kCodeCacheDir);
+
+ // Bind-mount /system/lib{,64}/<isa>/cpuinfo to /proc/cpuinfo.
+ // Failure is not fatal and will keep the native bridge in kPreInitialized.
+ state = NativeBridgeState::kPreInitialized;
+
+#ifndef __APPLE__
+ if (instruction_set == nullptr) {
+ return true;
+ }
+ size_t isa_len = strlen(instruction_set);
+ if (isa_len > 10) {
+ // 10 is a loose upper bound on the currently known instruction sets (a tight bound is 7 for
+ // x86_64 [including the trailing \0]). This is so we don't have to change here if there will
+ // be another instruction set in the future.
+ ALOGW("Instruction set %s is malformed, must be less than or equal to 10 characters.",
+ instruction_set);
+ return true;
+ }
+
+ // If the file does not exist, the mount command will fail,
+ // so we save the extra file existence check.
+ char cpuinfo_path[1024];
+
+#if defined(__ANDROID__)
+ snprintf(cpuinfo_path, sizeof(cpuinfo_path), "/system/lib"
+#ifdef __LP64__
+ "64"
+#endif // __LP64__
+ "/%s/cpuinfo", instruction_set);
+#else // !__ANDROID__
+ // To be able to test on the host, we hardwire a relative path.
+ snprintf(cpuinfo_path, sizeof(cpuinfo_path), "./cpuinfo");
+#endif
+
+ // Bind-mount.
+ if (TEMP_FAILURE_RETRY(mount(cpuinfo_path, // Source.
+ "/proc/cpuinfo", // Target.
+ nullptr, // FS type.
+ MS_BIND, // Mount flags: bind mount.
+ nullptr)) == -1) { // "Data."
+ ALOGW("Failed to bind-mount %s as /proc/cpuinfo: %s", cpuinfo_path, strerror(errno));
+ }
+#else // __APPLE__
+ UNUSED(instruction_set);
+ ALOGW("Mac OS does not support bind-mounting. Host simulation of native bridge impossible.");
+#endif
+
+ return true;
+}
+
+static void SetCpuAbi(JNIEnv* env, jclass build_class, const char* field, const char* value) {
+ if (value != nullptr) {
+ jfieldID field_id = env->GetStaticFieldID(build_class, field, "Ljava/lang/String;");
+ if (field_id == nullptr) {
+ env->ExceptionClear();
+ ALOGW("Could not find %s field.", field);
+ return;
+ }
+
+ jstring str = env->NewStringUTF(value);
+ if (str == nullptr) {
+ env->ExceptionClear();
+ ALOGW("Could not create string %s.", value);
+ return;
+ }
+
+ env->SetStaticObjectField(build_class, field_id, str);
+ }
+}
+
+// Set up the environment for the bridged app.
+static void SetupEnvironment(const NativeBridgeCallbacks* callbacks, JNIEnv* env, const char* isa) {
+ // Need a JNIEnv* to do anything.
+ if (env == nullptr) {
+ ALOGW("No JNIEnv* to set up app environment.");
+ return;
+ }
+
+ // Query the bridge for environment values.
+ const struct NativeBridgeRuntimeValues* env_values = callbacks->getAppEnv(isa);
+ if (env_values == nullptr) {
+ return;
+ }
+
+ // Keep the JNIEnv clean.
+ jint success = env->PushLocalFrame(16); // That should be small and large enough.
+ if (success < 0) {
+ // Out of memory, really borked.
+ ALOGW("Out of memory while setting up app environment.");
+ env->ExceptionClear();
+ return;
+ }
+
+ // Reset CPU_ABI & CPU_ABI2 to values required by the apps running with native bridge.
+ if (env_values->cpu_abi != nullptr || env_values->cpu_abi2 != nullptr ||
+ env_values->abi_count >= 0) {
+ jclass bclass_id = env->FindClass("android/os/Build");
+ if (bclass_id != nullptr) {
+ SetCpuAbi(env, bclass_id, "CPU_ABI", env_values->cpu_abi);
+ SetCpuAbi(env, bclass_id, "CPU_ABI2", env_values->cpu_abi2);
+ } else {
+ // For example in a host test environment.
+ env->ExceptionClear();
+ ALOGW("Could not find Build class.");
+ }
+ }
+
+ if (env_values->os_arch != nullptr) {
+ jclass sclass_id = env->FindClass("java/lang/System");
+ if (sclass_id != nullptr) {
+ jmethodID set_prop_id = env->GetStaticMethodID(sclass_id, "setUnchangeableSystemProperty",
+ "(Ljava/lang/String;Ljava/lang/String;)V");
+ if (set_prop_id != nullptr) {
+ // Init os.arch to the value reqired by the apps running with native bridge.
+ env->CallStaticVoidMethod(sclass_id, set_prop_id, env->NewStringUTF("os.arch"),
+ env->NewStringUTF(env_values->os_arch));
+ } else {
+ env->ExceptionClear();
+ ALOGW("Could not find System#setUnchangeableSystemProperty.");
+ }
+ } else {
+ env->ExceptionClear();
+ ALOGW("Could not find System class.");
+ }
+ }
+
+ // Make it pristine again.
+ env->PopLocalFrame(nullptr);
+}
+
+bool InitializeNativeBridge(JNIEnv* env, const char* instruction_set) {
+ // We expect only one place that calls InitializeNativeBridge: Runtime::DidForkFromZygote. At that
+ // point we are not multi-threaded, so we do not need locking here.
+
+ if (state == NativeBridgeState::kPreInitialized) {
+ // Check for code cache: if it doesn't exist try to create it.
+ struct stat st;
+ if (stat(app_code_cache_dir, &st) == -1) {
+ if (errno == ENOENT) {
+ if (mkdir(app_code_cache_dir, S_IRWXU | S_IRWXG | S_IXOTH) == -1) {
+ ALOGW("Cannot create code cache directory %s: %s.", app_code_cache_dir, strerror(errno));
+ ReleaseAppCodeCacheDir();
+ }
+ } else {
+ ALOGW("Cannot stat code cache directory %s: %s.", app_code_cache_dir, strerror(errno));
+ ReleaseAppCodeCacheDir();
+ }
+ } else if (!S_ISDIR(st.st_mode)) {
+ ALOGW("Code cache is not a directory %s.", app_code_cache_dir);
+ ReleaseAppCodeCacheDir();
+ }
+
+ // If we're still PreInitialized (dind't fail the code cache checks) try to initialize.
+ if (state == NativeBridgeState::kPreInitialized) {
+ if (callbacks->initialize(runtime_callbacks, app_code_cache_dir, instruction_set)) {
+ SetupEnvironment(callbacks, env, instruction_set);
+ state = NativeBridgeState::kInitialized;
+ // We no longer need the code cache path, release the memory.
+ ReleaseAppCodeCacheDir();
+ } else {
+ // Unload the library.
+ dlclose(native_bridge_handle);
+ CloseNativeBridge(true);
+ }
+ }
+ } else {
+ CloseNativeBridge(true);
+ }
+
+ return state == NativeBridgeState::kInitialized;
+}
+
+void UnloadNativeBridge() {
+ // We expect only one place that calls UnloadNativeBridge: Runtime::DidForkFromZygote. At that
+ // point we are not multi-threaded, so we do not need locking here.
+
+ switch(state) {
+ case NativeBridgeState::kOpened:
+ case NativeBridgeState::kPreInitialized:
+ case NativeBridgeState::kInitialized:
+ // Unload.
+ dlclose(native_bridge_handle);
+ CloseNativeBridge(false);
+ break;
+
+ case NativeBridgeState::kNotSetup:
+ // Not even set up. Error.
+ CloseNativeBridge(true);
+ break;
+
+ case NativeBridgeState::kClosed:
+ // Ignore.
+ break;
+ }
+}
+
+bool NativeBridgeError() {
+ return had_error;
+}
+
+bool NativeBridgeAvailable() {
+ return state == NativeBridgeState::kOpened
+ || state == NativeBridgeState::kPreInitialized
+ || state == NativeBridgeState::kInitialized;
+}
+
+bool NativeBridgeInitialized() {
+ // Calls of this are supposed to happen in a state where the native bridge is stable, i.e., after
+ // Runtime::DidForkFromZygote. In that case we do not need a lock.
+ return state == NativeBridgeState::kInitialized;
+}
+
+void* NativeBridgeLoadLibrary(const char* libpath, int flag) {
+ if (NativeBridgeInitialized()) {
+ return callbacks->loadLibrary(libpath, flag);
+ }
+ return nullptr;
+}
+
+void* NativeBridgeGetTrampoline(void* handle, const char* name, const char* shorty,
+ uint32_t len) {
+ if (NativeBridgeInitialized()) {
+ return callbacks->getTrampoline(handle, name, shorty, len);
+ }
+ return nullptr;
+}
+
+bool NativeBridgeIsSupported(const char* libpath) {
+ if (NativeBridgeInitialized()) {
+ return callbacks->isSupported(libpath);
+ }
+ return false;
+}
+
+uint32_t NativeBridgeGetVersion() {
+ if (NativeBridgeAvailable()) {
+ return callbacks->version;
+ }
+ return 0;
+}
+
+NativeBridgeSignalHandlerFn NativeBridgeGetSignalHandler(int signal) {
+ if (NativeBridgeInitialized()) {
+ if (isCompatibleWith(SIGNAL_VERSION)) {
+ return callbacks->getSignalHandler(signal);
+ } else {
+ ALOGE("not compatible with version %d, cannot get signal handler", SIGNAL_VERSION);
+ }
+ }
+ return nullptr;
+}
+
+int NativeBridgeUnloadLibrary(void* handle) {
+ if (NativeBridgeInitialized()) {
+ if (isCompatibleWith(NAMESPACE_VERSION)) {
+ return callbacks->unloadLibrary(handle);
+ } else {
+ ALOGE("not compatible with version %d, cannot unload library", NAMESPACE_VERSION);
+ }
+ }
+ return -1;
+}
+
+const char* NativeBridgeGetError() {
+ if (NativeBridgeInitialized()) {
+ if (isCompatibleWith(NAMESPACE_VERSION)) {
+ return callbacks->getError();
+ } else {
+ return "native bridge implementation is not compatible with version 3, cannot get message";
+ }
+ }
+ return "native bridge is not initialized";
+}
+
+bool NativeBridgeIsPathSupported(const char* path) {
+ if (NativeBridgeInitialized()) {
+ if (isCompatibleWith(NAMESPACE_VERSION)) {
+ return callbacks->isPathSupported(path);
+ } else {
+ ALOGE("not compatible with version %d, cannot check via library path", NAMESPACE_VERSION);
+ }
+ }
+ return false;
+}
+
+bool NativeBridgeInitAnonymousNamespace(const char* public_ns_sonames,
+ const char* anon_ns_library_path) {
+ if (NativeBridgeInitialized()) {
+ if (isCompatibleWith(NAMESPACE_VERSION)) {
+ return callbacks->initAnonymousNamespace(public_ns_sonames, anon_ns_library_path);
+ } else {
+ ALOGE("not compatible with version %d, cannot init namespace", NAMESPACE_VERSION);
+ }
+ }
+
+ return false;
+}
+
+native_bridge_namespace_t* NativeBridgeCreateNamespace(const char* name,
+ const char* ld_library_path,
+ const char* default_library_path,
+ uint64_t type,
+ const char* permitted_when_isolated_path,
+ native_bridge_namespace_t* parent_ns) {
+ if (NativeBridgeInitialized()) {
+ if (isCompatibleWith(NAMESPACE_VERSION)) {
+ return callbacks->createNamespace(name,
+ ld_library_path,
+ default_library_path,
+ type,
+ permitted_when_isolated_path,
+ parent_ns);
+ } else {
+ ALOGE("not compatible with version %d, cannot create namespace %s", NAMESPACE_VERSION, name);
+ }
+ }
+
+ return nullptr;
+}
+
+bool NativeBridgeLinkNamespaces(native_bridge_namespace_t* from, native_bridge_namespace_t* to,
+ const char* shared_libs_sonames) {
+ if (NativeBridgeInitialized()) {
+ if (isCompatibleWith(NAMESPACE_VERSION)) {
+ return callbacks->linkNamespaces(from, to, shared_libs_sonames);
+ } else {
+ ALOGE("not compatible with version %d, cannot init namespace", NAMESPACE_VERSION);
+ }
+ }
+
+ return false;
+}
+
+native_bridge_namespace_t* NativeBridgeGetExportedNamespace(const char* name) {
+ if (!NativeBridgeInitialized()) {
+ return nullptr;
+ }
+
+ if (isCompatibleWith(RUNTIME_NAMESPACE_VERSION)) {
+ return callbacks->getExportedNamespace(name);
+ }
+
+ // sphal is vendor namespace name -> use v4 callback in the case NB callbacks
+ // are not compatible with v5
+ if (isCompatibleWith(VENDOR_NAMESPACE_VERSION) && name != nullptr && strcmp("sphal", name) == 0) {
+ return callbacks->getVendorNamespace();
+ }
+
+ return nullptr;
+}
+
+void* NativeBridgeLoadLibraryExt(const char* libpath, int flag, native_bridge_namespace_t* ns) {
+ if (NativeBridgeInitialized()) {
+ if (isCompatibleWith(NAMESPACE_VERSION)) {
+ return callbacks->loadLibraryExt(libpath, flag, ns);
+ } else {
+ ALOGE("not compatible with version %d, cannot load library in namespace", NAMESPACE_VERSION);
+ }
+ }
+ return nullptr;
+}
+
+} // extern "C"
+
+} // namespace android