| /* | 
 |  * Copyright (C) 2015 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 "nativeloader" | 
 |  | 
 | #include "nativeloader/native_loader.h" | 
 |  | 
 | #include <dlfcn.h> | 
 | #include <sys/types.h> | 
 |  | 
 | #include <memory> | 
 | #include <mutex> | 
 | #include <string> | 
 | #include <vector> | 
 |  | 
 | #include <android-base/file.h> | 
 | #include <android-base/macros.h> | 
 | #include <android-base/strings.h> | 
 | #include <nativebridge/native_bridge.h> | 
 | #include <nativehelper/ScopedUtfChars.h> | 
 |  | 
 | #ifdef __ANDROID__ | 
 | #include <log/log.h> | 
 | #include "library_namespaces.h" | 
 | #include "nativeloader/dlext_namespaces.h" | 
 | #endif | 
 |  | 
 | namespace android { | 
 |  | 
 | namespace { | 
 | #if defined(__ANDROID__) | 
 | using android::nativeloader::LibraryNamespaces; | 
 |  | 
 | constexpr const char* kApexPath = "/apex/"; | 
 |  | 
 | std::mutex g_namespaces_mutex; | 
 | LibraryNamespaces* g_namespaces = new LibraryNamespaces; | 
 |  | 
 | android_namespace_t* FindExportedNamespace(const char* caller_location) { | 
 |   std::string location = caller_location; | 
 |   // Lots of implicit assumptions here: we expect `caller_location` to be of the form: | 
 |   // /apex/com.android...modulename/... | 
 |   // | 
 |   // And we extract from it 'modulename', which is the name of the linker namespace. | 
 |   if (android::base::StartsWith(location, kApexPath)) { | 
 |     size_t slash_index = location.find_first_of('/', strlen(kApexPath)); | 
 |     LOG_ALWAYS_FATAL_IF((slash_index == std::string::npos), | 
 |                         "Error finding namespace of apex: no slash in path %s", caller_location); | 
 |     size_t dot_index = location.find_last_of('.', slash_index); | 
 |     LOG_ALWAYS_FATAL_IF((dot_index == std::string::npos), | 
 |                         "Error finding namespace of apex: no dot in apex name %s", caller_location); | 
 |     std::string name = location.substr(dot_index + 1, slash_index - dot_index - 1); | 
 |     // TODO(b/139408016): Rename the runtime namespace to "art". | 
 |     if (name == "art") { | 
 |       name = "runtime"; | 
 |     } | 
 |     android_namespace_t* boot_namespace = android_get_exported_namespace(name.c_str()); | 
 |     LOG_ALWAYS_FATAL_IF((boot_namespace == nullptr), | 
 |                         "Error finding namespace of apex: no namespace called %s", name.c_str()); | 
 |     return boot_namespace; | 
 |   } | 
 |   return nullptr; | 
 | } | 
 | #endif  // #if defined(__ANDROID__) | 
 | }  // namespace | 
 |  | 
 | void InitializeNativeLoader() { | 
 | #if defined(__ANDROID__) | 
 |   std::lock_guard<std::mutex> guard(g_namespaces_mutex); | 
 |   g_namespaces->Initialize(); | 
 | #endif | 
 | } | 
 |  | 
 | void ResetNativeLoader() { | 
 | #if defined(__ANDROID__) | 
 |   std::lock_guard<std::mutex> guard(g_namespaces_mutex); | 
 |   g_namespaces->Reset(); | 
 | #endif | 
 | } | 
 |  | 
 | jstring CreateClassLoaderNamespace(JNIEnv* env, int32_t target_sdk_version, jobject class_loader, | 
 |                                    bool is_shared, jstring dex_path, jstring library_path, | 
 |                                    jstring permitted_path) { | 
 | #if defined(__ANDROID__) | 
 |   std::lock_guard<std::mutex> guard(g_namespaces_mutex); | 
 |   auto ns = g_namespaces->Create(env, target_sdk_version, class_loader, is_shared, dex_path, | 
 |                                  library_path, permitted_path); | 
 |   if (!ns) { | 
 |     return env->NewStringUTF(ns.error().message().c_str()); | 
 |   } | 
 | #else | 
 |   UNUSED(env, target_sdk_version, class_loader, is_shared, dex_path, library_path, permitted_path); | 
 | #endif | 
 |   return nullptr; | 
 | } | 
 |  | 
 | void* OpenNativeLibrary(JNIEnv* env, int32_t target_sdk_version, const char* path, | 
 |                         jobject class_loader, const char* caller_location, jstring library_path, | 
 |                         bool* needs_native_bridge, char** error_msg) { | 
 | #if defined(__ANDROID__) | 
 |   UNUSED(target_sdk_version); | 
 |   if (class_loader == nullptr) { | 
 |     *needs_native_bridge = false; | 
 |     if (caller_location != nullptr) { | 
 |       android_namespace_t* boot_namespace = FindExportedNamespace(caller_location); | 
 |       if (boot_namespace != nullptr) { | 
 |         const android_dlextinfo dlextinfo = { | 
 |             .flags = ANDROID_DLEXT_USE_NAMESPACE, | 
 |             .library_namespace = boot_namespace, | 
 |         }; | 
 |         void* handle = android_dlopen_ext(path, RTLD_NOW, &dlextinfo); | 
 |         if (handle == nullptr) { | 
 |           *error_msg = strdup(dlerror()); | 
 |         } | 
 |         return handle; | 
 |       } | 
 |     } | 
 |     void* handle = dlopen(path, RTLD_NOW); | 
 |     if (handle == nullptr) { | 
 |       *error_msg = strdup(dlerror()); | 
 |     } | 
 |     return handle; | 
 |   } | 
 |  | 
 |   std::lock_guard<std::mutex> guard(g_namespaces_mutex); | 
 |   NativeLoaderNamespace* ns; | 
 |  | 
 |   if ((ns = g_namespaces->FindNamespaceByClassLoader(env, class_loader)) == nullptr) { | 
 |     // This is the case where the classloader was not created by ApplicationLoaders | 
 |     // In this case we create an isolated not-shared namespace for it. | 
 |     Result<NativeLoaderNamespace*> isolated_ns = | 
 |         g_namespaces->Create(env, target_sdk_version, class_loader, false /* is_shared */, nullptr, | 
 |                              library_path, nullptr); | 
 |     if (!isolated_ns) { | 
 |       *error_msg = strdup(isolated_ns.error().message().c_str()); | 
 |       return nullptr; | 
 |     } else { | 
 |       ns = *isolated_ns; | 
 |     } | 
 |   } | 
 |  | 
 |   return OpenNativeLibraryInNamespace(ns, path, needs_native_bridge, error_msg); | 
 | #else | 
 |   UNUSED(env, target_sdk_version, class_loader, caller_location); | 
 |  | 
 |   // Do some best effort to emulate library-path support. It will not | 
 |   // work for dependencies. | 
 |   // | 
 |   // Note: null has a special meaning and must be preserved. | 
 |   std::string c_library_path;  // Empty string by default. | 
 |   if (library_path != nullptr && path != nullptr && path[0] != '/') { | 
 |     ScopedUtfChars library_path_utf_chars(env, library_path); | 
 |     c_library_path = library_path_utf_chars.c_str(); | 
 |   } | 
 |  | 
 |   std::vector<std::string> library_paths = base::Split(c_library_path, ":"); | 
 |  | 
 |   for (const std::string& lib_path : library_paths) { | 
 |     *needs_native_bridge = false; | 
 |     const char* path_arg; | 
 |     std::string complete_path; | 
 |     if (path == nullptr) { | 
 |       // Preserve null. | 
 |       path_arg = nullptr; | 
 |     } else { | 
 |       complete_path = lib_path; | 
 |       if (!complete_path.empty()) { | 
 |         complete_path.append("/"); | 
 |       } | 
 |       complete_path.append(path); | 
 |       path_arg = complete_path.c_str(); | 
 |     } | 
 |     void* handle = dlopen(path_arg, RTLD_NOW); | 
 |     if (handle != nullptr) { | 
 |       return handle; | 
 |     } | 
 |     if (NativeBridgeIsSupported(path_arg)) { | 
 |       *needs_native_bridge = true; | 
 |       handle = NativeBridgeLoadLibrary(path_arg, RTLD_NOW); | 
 |       if (handle != nullptr) { | 
 |         return handle; | 
 |       } | 
 |       *error_msg = strdup(NativeBridgeGetError()); | 
 |     } else { | 
 |       *error_msg = strdup(dlerror()); | 
 |     } | 
 |   } | 
 |   return nullptr; | 
 | #endif | 
 | } | 
 |  | 
 | bool CloseNativeLibrary(void* handle, const bool needs_native_bridge, char** error_msg) { | 
 |   bool success; | 
 |   if (needs_native_bridge) { | 
 |     success = (NativeBridgeUnloadLibrary(handle) == 0); | 
 |     if (!success) { | 
 |       *error_msg = strdup(NativeBridgeGetError()); | 
 |     } | 
 |   } else { | 
 |     success = (dlclose(handle) == 0); | 
 |     if (!success) { | 
 |       *error_msg = strdup(dlerror()); | 
 |     } | 
 |   } | 
 |  | 
 |   return success; | 
 | } | 
 |  | 
 | void NativeLoaderFreeErrorMessage(char* msg) { | 
 |   // The error messages get allocated through strdup, so we must call free on them. | 
 |   free(msg); | 
 | } | 
 |  | 
 | #if defined(__ANDROID__) | 
 | void* OpenNativeLibraryInNamespace(NativeLoaderNamespace* ns, const char* path, | 
 |                                    bool* needs_native_bridge, char** error_msg) { | 
 |   auto handle = ns->Load(path); | 
 |   if (!handle && error_msg != nullptr) { | 
 |     *error_msg = strdup(handle.error().message().c_str()); | 
 |   } | 
 |   if (needs_native_bridge != nullptr) { | 
 |     *needs_native_bridge = ns->IsBridged(); | 
 |   } | 
 |   return handle ? *handle : nullptr; | 
 | } | 
 |  | 
 | // native_bridge_namespaces are not supported for callers of this function. | 
 | // This function will return nullptr in the case when application is running | 
 | // on native bridge. | 
 | android_namespace_t* FindNamespaceByClassLoader(JNIEnv* env, jobject class_loader) { | 
 |   std::lock_guard<std::mutex> guard(g_namespaces_mutex); | 
 |   NativeLoaderNamespace* ns = g_namespaces->FindNamespaceByClassLoader(env, class_loader); | 
 |   if (ns != nullptr && !ns->IsBridged()) { | 
 |     return ns->ToRawAndroidNamespace(); | 
 |   } | 
 |   return nullptr; | 
 | } | 
 |  | 
 | NativeLoaderNamespace* FindNativeLoaderNamespaceByClassLoader(JNIEnv* env, jobject class_loader) { | 
 |   std::lock_guard<std::mutex> guard(g_namespaces_mutex); | 
 |   return g_namespaces->FindNamespaceByClassLoader(env, class_loader); | 
 | } | 
 | #endif | 
 |  | 
 | };  // namespace android |