native_loader.cpp revision d047c925af62e1fe28fcd1c1940df4afe18d458a 
1/*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "nativeloader/native_loader.h"
18#include "ScopedUtfChars.h"
19
20#include <dlfcn.h>
21#ifdef __ANDROID__
22#include <android/dlext.h>
23#include "cutils/properties.h"
24#include "log/log.h"
25#endif
26
27#include <algorithm>
28#include <vector>
29#include <string>
30#include <mutex>
31
32#include "android-base/macros.h"
33#include "android-base/strings.h"
34
35namespace android {
36
37#ifdef __ANDROID__
38// TODO(dimitry): move this to system properties.
39static const char* kPublicNativeLibraries = "libandroid.so:"
40                                            "libc.so:"
41                                            "libcamera2ndk.so:"
42                                            "libdl.so:"
43                                            "libEGL.so:"
44                                            "libGLESv1_CM.so:"
45                                            "libGLESv2.so:"
46                                            "libGLESv3.so:"
47                                            "libicui18n.so:"
48                                            "libicuuc.so:"
49                                            "libjnigraphics.so:"
50                                            "liblog.so:"
51                                            "libmediandk.so:"
52                                            "libm.so:"
53                                            "libOpenMAXAL.so:"
54                                            "libOpenSLES.so:"
55                                            "libRS.so:"
56                                            "libstdc++.so:"
57                                            "libvulkan.so:"
58                                            "libwebviewchromium_plat_support.so:"
59                                            "libz.so";
60
61class LibraryNamespaces {
62 public:
63  LibraryNamespaces() : initialized_(false) { }
64
65  android_namespace_t* Create(JNIEnv* env,
66                              jobject class_loader,
67                              bool is_shared,
68                              jstring java_library_path,
69                              jstring java_permitted_path,
70                              int32_t target_sdk_version) {
71    ScopedUtfChars library_path(env, java_library_path);
72
73    std::string permitted_path;
74    if (java_permitted_path != nullptr) {
75      ScopedUtfChars path(env, java_permitted_path);
76      permitted_path = path.c_str();
77    }
78
79    if (!initialized_ && !InitPublicNamespace(library_path.c_str(), target_sdk_version)) {
80      return nullptr;
81    }
82
83    std::lock_guard<std::mutex> guard(mutex_);
84
85    android_namespace_t* ns = FindNamespaceByClassLoader(env, class_loader);
86
87    LOG_FATAL_IF(ns != nullptr, "There is already a namespace associated with this classloader");
88
89    uint64_t namespace_type = ANDROID_NAMESPACE_TYPE_ISOLATED;
90    if (is_shared) {
91      namespace_type |= ANDROID_NAMESPACE_TYPE_SHARED;
92    }
93
94    ns = android_create_namespace("classloader-namespace",
95                                  nullptr,
96                                  library_path.c_str(),
97                                  namespace_type,
98                                  java_permitted_path != nullptr ?
99                                      permitted_path.c_str() :
100                                      nullptr);
101
102    if (ns != nullptr) {
103      namespaces_.push_back(std::make_pair(env->NewWeakGlobalRef(class_loader), ns));
104    }
105
106    return ns;
107  }
108
109  android_namespace_t* FindNamespaceByClassLoader(JNIEnv* env, jobject class_loader) {
110    auto it = std::find_if(namespaces_.begin(), namespaces_.end(),
111                [&](const std::pair<jweak, android_namespace_t*>& value) {
112                  return env->IsSameObject(value.first, class_loader);
113                });
114    return it != namespaces_.end() ? it->second : nullptr;
115  }
116
117  void PreloadPublicLibraries() {
118    // android_init_namespaces() expects all the public libraries
119    // to be loaded so that they can be found by soname alone.
120    std::vector<std::string> sonames = android::base::Split(kPublicNativeLibraries, ":");
121    for (const auto& soname : sonames) {
122      dlopen(soname.c_str(), RTLD_NOW | RTLD_NODELETE);
123    }
124  }
125
126 private:
127  bool InitPublicNamespace(const char* library_path, int32_t target_sdk_version) {
128    // Some apps call dlopen from generated code unknown to linker in which
129    // case linker uses anonymous namespace. See b/25844435 for details.
130    std::string publicNativeLibraries = kPublicNativeLibraries;
131
132    // TODO (dimitry): This is a workaround for http://b/26436837
133    // will be removed before the release.
134    if (target_sdk_version <= 23) {
135      publicNativeLibraries += ":libart.so";
136    }
137    // END OF WORKAROUND
138
139    initialized_ = android_init_namespaces(publicNativeLibraries.c_str(), library_path);
140
141    return initialized_;
142  }
143
144  bool initialized_;
145  std::mutex mutex_;
146  std::vector<std::pair<jweak, android_namespace_t*>> namespaces_;
147
148  DISALLOW_COPY_AND_ASSIGN(LibraryNamespaces);
149};
150
151static LibraryNamespaces* g_namespaces = new LibraryNamespaces;
152
153static bool namespaces_enabled(uint32_t target_sdk_version) {
154  return target_sdk_version > 0;
155}
156#endif
157
158void PreloadPublicNativeLibraries() {
159#if defined(__ANDROID__)
160  g_namespaces->PreloadPublicLibraries();
161#endif
162}
163
164
165jstring CreateClassLoaderNamespace(JNIEnv* env,
166                                   int32_t target_sdk_version,
167                                   jobject class_loader,
168                                   bool is_shared,
169                                   jstring library_path,
170                                   jstring permitted_path) {
171#if defined(__ANDROID__)
172  if (!namespaces_enabled(target_sdk_version)) {
173    return nullptr;
174  }
175
176  android_namespace_t* ns = g_namespaces->Create(env,
177                                                 class_loader,
178                                                 is_shared,
179                                                 library_path,
180                                                 permitted_path,
181                                                 target_sdk_version);
182  if (ns == nullptr) {
183    return env->NewStringUTF(dlerror());
184  }
185#else
186  UNUSED(env, target_sdk_version, class_loader, is_shared,
187         library_path, permitted_path);
188#endif
189  return nullptr;
190}
191
192void* OpenNativeLibrary(JNIEnv* env,
193                        int32_t target_sdk_version,
194                        const char* path,
195                        jobject class_loader,
196                        jstring library_path) {
197#if defined(__ANDROID__)
198  if (!namespaces_enabled(target_sdk_version) || class_loader == nullptr) {
199    return dlopen(path, RTLD_NOW);
200  }
201
202  android_namespace_t* ns = g_namespaces->FindNamespaceByClassLoader(env, class_loader);
203
204  if (ns == nullptr) {
205    // This is the case where the classloader was not created by ApplicationLoaders
206    // In this case we create an isolated not-shared namespace for it.
207    ns = g_namespaces->Create(env, class_loader, false, library_path, nullptr, target_sdk_version);
208    if (ns == nullptr) {
209      return nullptr;
210    }
211  }
212
213  android_dlextinfo extinfo;
214  extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
215  extinfo.library_namespace = ns;
216
217  return android_dlopen_ext(path, RTLD_NOW, &extinfo);
218#else
219  UNUSED(env, target_sdk_version, class_loader, library_path);
220  return dlopen(path, RTLD_NOW);
221#endif
222}
223
224#if defined(__ANDROID__)
225android_namespace_t* FindNamespaceByClassLoader(JNIEnv* env, jobject class_loader) {
226  return g_namespaces->FindNamespaceByClassLoader(env, class_loader);
227}
228#endif
229
230}; //  android namespace
231