| /* |
| * Copyright (C) 2019 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 "native_loader_namespace.h" |
| |
| #include <dlfcn.h> |
| |
| #include <functional> |
| |
| #include <android-base/strings.h> |
| #include <log/log.h> |
| #include <nativebridge/native_bridge.h> |
| |
| #include "nativeloader/dlext_namespaces.h" |
| |
| using android::base::Error; |
| |
| namespace android { |
| |
| namespace { |
| |
| constexpr const char* kDefaultNamespaceName = "default"; |
| constexpr const char* kSystemNamespaceName = "system"; |
| |
| std::string GetLinkerError(bool is_bridged) { |
| const char* msg = is_bridged ? NativeBridgeGetError() : dlerror(); |
| if (msg == nullptr) { |
| return "no error"; |
| } |
| return std::string(msg); |
| } |
| |
| } // namespace |
| |
| Result<NativeLoaderNamespace> NativeLoaderNamespace::GetExportedNamespace(const std::string& name, |
| bool is_bridged) { |
| if (!is_bridged) { |
| auto raw = android_get_exported_namespace(name.c_str()); |
| if (raw != nullptr) { |
| return NativeLoaderNamespace(name, raw); |
| } |
| } else { |
| auto raw = NativeBridgeGetExportedNamespace(name.c_str()); |
| if (raw != nullptr) { |
| return NativeLoaderNamespace(name, raw); |
| } |
| } |
| return Errorf("namespace {} does not exist or exported", name); |
| } |
| |
| // The system namespace is called "default" for binaries in /system and |
| // "system" for those in the Runtime APEX. Try "system" first since |
| // "default" always exists. |
| Result<NativeLoaderNamespace> NativeLoaderNamespace::GetSystemNamespace(bool is_bridged) { |
| auto ns = GetExportedNamespace(kSystemNamespaceName, is_bridged); |
| if (ns) return ns; |
| ns = GetExportedNamespace(kDefaultNamespaceName, is_bridged); |
| if (ns) return ns; |
| |
| // If nothing is found, return NativeLoaderNamespace constructed from nullptr. |
| // nullptr also means default namespace to the linker. |
| if (!is_bridged) { |
| return NativeLoaderNamespace(kDefaultNamespaceName, static_cast<android_namespace_t*>(nullptr)); |
| } else { |
| return NativeLoaderNamespace(kDefaultNamespaceName, |
| static_cast<native_bridge_namespace_t*>(nullptr)); |
| } |
| } |
| |
| Result<NativeLoaderNamespace> NativeLoaderNamespace::Create( |
| const std::string& name, const std::string& search_paths, const std::string& permitted_paths, |
| const NativeLoaderNamespace* parent, bool is_shared, bool is_greylist_enabled, |
| bool also_used_as_anonymous) { |
| bool is_bridged = false; |
| if (parent != nullptr) { |
| is_bridged = parent->IsBridged(); |
| } else if (!search_paths.empty()) { |
| is_bridged = NativeBridgeIsPathSupported(search_paths.c_str()); |
| } |
| |
| // Fall back to the system namespace if no parent is set. |
| auto system_ns = GetSystemNamespace(is_bridged); |
| if (!system_ns) { |
| return system_ns.error(); |
| } |
| const NativeLoaderNamespace& effective_parent = parent != nullptr ? *parent : *system_ns; |
| |
| // All namespaces for apps are isolated |
| uint64_t type = ANDROID_NAMESPACE_TYPE_ISOLATED; |
| |
| // The namespace is also used as the anonymous namespace |
| // which is used when the linker fails to determine the caller address |
| if (also_used_as_anonymous) { |
| type |= ANDROID_NAMESPACE_TYPE_ALSO_USED_AS_ANONYMOUS; |
| } |
| |
| // Bundled apps have access to all system libraries that are currently loaded |
| // in the default namespace |
| if (is_shared) { |
| type |= ANDROID_NAMESPACE_TYPE_SHARED; |
| } |
| if (is_greylist_enabled) { |
| type |= ANDROID_NAMESPACE_TYPE_GREYLIST_ENABLED; |
| } |
| |
| if (!is_bridged) { |
| android_namespace_t* raw = |
| android_create_namespace(name.c_str(), nullptr, search_paths.c_str(), type, |
| permitted_paths.c_str(), effective_parent.ToRawAndroidNamespace()); |
| if (raw != nullptr) { |
| return NativeLoaderNamespace(name, raw); |
| } |
| } else { |
| native_bridge_namespace_t* raw = NativeBridgeCreateNamespace( |
| name.c_str(), nullptr, search_paths.c_str(), type, permitted_paths.c_str(), |
| effective_parent.ToRawNativeBridgeNamespace()); |
| if (raw != nullptr) { |
| return NativeLoaderNamespace(name, raw); |
| } |
| } |
| return Errorf("failed to create {} namespace name:{}, search_paths:{}, permitted_paths:{}", |
| is_bridged ? "bridged" : "native", name, search_paths, permitted_paths); |
| } |
| |
| Result<void> NativeLoaderNamespace::Link(const NativeLoaderNamespace& target, |
| const std::string& shared_libs) const { |
| LOG_ALWAYS_FATAL_IF(shared_libs.empty(), "empty share lib when linking %s to %s", |
| this->name().c_str(), target.name().c_str()); |
| if (!IsBridged()) { |
| if (android_link_namespaces(this->ToRawAndroidNamespace(), target.ToRawAndroidNamespace(), |
| shared_libs.c_str())) { |
| return {}; |
| } |
| } else { |
| if (NativeBridgeLinkNamespaces(this->ToRawNativeBridgeNamespace(), |
| target.ToRawNativeBridgeNamespace(), shared_libs.c_str())) { |
| return {}; |
| } |
| } |
| return Error() << GetLinkerError(IsBridged()); |
| } |
| |
| Result<void*> NativeLoaderNamespace::Load(const char* lib_name) const { |
| if (!IsBridged()) { |
| android_dlextinfo extinfo; |
| extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE; |
| extinfo.library_namespace = this->ToRawAndroidNamespace(); |
| void* handle = android_dlopen_ext(lib_name, RTLD_NOW, &extinfo); |
| if (handle != nullptr) { |
| return handle; |
| } |
| } else { |
| void* handle = |
| NativeBridgeLoadLibraryExt(lib_name, RTLD_NOW, this->ToRawNativeBridgeNamespace()); |
| if (handle != nullptr) { |
| return handle; |
| } |
| } |
| return Error() << GetLinkerError(IsBridged()); |
| } |
| |
| } // namespace android |