1 /*
2  * Copyright (C) 2017 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 #define ATRACE_TAG ATRACE_TAG_RESOURCES
18 
19 #include "android-base/macros.h"
20 #include "android-base/stringprintf.h"
21 #include "android-base/unique_fd.h"
22 #include "androidfw/ApkAssets.h"
23 #include "utils/misc.h"
24 #include "utils/Trace.h"
25 
26 #include "core_jni_helpers.h"
27 #include "jni.h"
28 #include "nativehelper/ScopedUtfChars.h"
29 
30 using ::android::base::unique_fd;
31 
32 namespace android {
33 
NativeLoad(JNIEnv * env,jclass,jstring java_path,jboolean system,jboolean force_shared_lib,jboolean overlay)34 static jlong NativeLoad(JNIEnv* env, jclass /*clazz*/, jstring java_path, jboolean system,
35                         jboolean force_shared_lib, jboolean overlay) {
36   ScopedUtfChars path(env, java_path);
37   if (path.c_str() == nullptr) {
38     return 0;
39   }
40 
41   ATRACE_NAME(base::StringPrintf("LoadApkAssets(%s)", path.c_str()).c_str());
42 
43   std::unique_ptr<const ApkAssets> apk_assets;
44   if (overlay) {
45     apk_assets = ApkAssets::LoadOverlay(path.c_str(), system);
46   } else if (force_shared_lib) {
47     apk_assets = ApkAssets::LoadAsSharedLibrary(path.c_str(), system);
48   } else {
49     apk_assets = ApkAssets::Load(path.c_str(), system);
50   }
51 
52   if (apk_assets == nullptr) {
53     std::string error_msg = base::StringPrintf("Failed to load asset path %s", path.c_str());
54     jniThrowException(env, "java/io/IOException", error_msg.c_str());
55     return 0;
56   }
57   return reinterpret_cast<jlong>(apk_assets.release());
58 }
59 
NativeLoadFromFd(JNIEnv * env,jclass,jobject file_descriptor,jstring friendly_name,jboolean system,jboolean force_shared_lib)60 static jlong NativeLoadFromFd(JNIEnv* env, jclass /*clazz*/, jobject file_descriptor,
61                               jstring friendly_name, jboolean system, jboolean force_shared_lib) {
62   ScopedUtfChars friendly_name_utf8(env, friendly_name);
63   if (friendly_name_utf8.c_str() == nullptr) {
64     return 0;
65   }
66 
67   ATRACE_NAME(base::StringPrintf("LoadApkAssetsFd(%s)", friendly_name_utf8.c_str()).c_str());
68 
69   int fd = jniGetFDFromFileDescriptor(env, file_descriptor);
70   if (fd < 0) {
71     jniThrowException(env, "java/lang/IllegalArgumentException", "Bad FileDescriptor");
72     return 0;
73   }
74 
75   unique_fd dup_fd(::dup(fd));
76   if (dup_fd < 0) {
77     jniThrowIOException(env, errno);
78     return 0;
79   }
80 
81   std::unique_ptr<const ApkAssets> apk_assets = ApkAssets::LoadFromFd(std::move(dup_fd),
82                                                                       friendly_name_utf8.c_str(),
83                                                                       system, force_shared_lib);
84   if (apk_assets == nullptr) {
85     std::string error_msg = base::StringPrintf("Failed to load asset path %s from fd %d",
86                                                friendly_name_utf8.c_str(), dup_fd.get());
87     jniThrowException(env, "java/io/IOException", error_msg.c_str());
88     return 0;
89   }
90   return reinterpret_cast<jlong>(apk_assets.release());
91 }
92 
NativeDestroy(JNIEnv *,jclass,jlong ptr)93 static void NativeDestroy(JNIEnv* /*env*/, jclass /*clazz*/, jlong ptr) {
94   delete reinterpret_cast<ApkAssets*>(ptr);
95 }
96 
NativeGetAssetPath(JNIEnv * env,jclass,jlong ptr)97 static jstring NativeGetAssetPath(JNIEnv* env, jclass /*clazz*/, jlong ptr) {
98   const ApkAssets* apk_assets = reinterpret_cast<const ApkAssets*>(ptr);
99   return env->NewStringUTF(apk_assets->GetPath().c_str());
100 }
101 
NativeGetStringBlock(JNIEnv *,jclass,jlong ptr)102 static jlong NativeGetStringBlock(JNIEnv* /*env*/, jclass /*clazz*/, jlong ptr) {
103   const ApkAssets* apk_assets = reinterpret_cast<const ApkAssets*>(ptr);
104   return reinterpret_cast<jlong>(apk_assets->GetLoadedArsc()->GetStringPool());
105 }
106 
NativeIsUpToDate(JNIEnv *,jclass,jlong ptr)107 static jboolean NativeIsUpToDate(JNIEnv* /*env*/, jclass /*clazz*/, jlong ptr) {
108   const ApkAssets* apk_assets = reinterpret_cast<const ApkAssets*>(ptr);
109   (void)apk_assets;
110   return JNI_TRUE;
111 }
112 
NativeOpenXml(JNIEnv * env,jclass,jlong ptr,jstring file_name)113 static jlong NativeOpenXml(JNIEnv* env, jclass /*clazz*/, jlong ptr, jstring file_name) {
114   ScopedUtfChars path_utf8(env, file_name);
115   if (path_utf8.c_str() == nullptr) {
116     return 0;
117   }
118 
119   const ApkAssets* apk_assets = reinterpret_cast<const ApkAssets*>(ptr);
120   std::unique_ptr<Asset> asset = apk_assets->Open(path_utf8.c_str(),
121                                                   Asset::AccessMode::ACCESS_RANDOM);
122   if (asset == nullptr) {
123     jniThrowException(env, "java/io/FileNotFoundException", path_utf8.c_str());
124     return 0;
125   }
126 
127   // DynamicRefTable is only needed when looking up resource references. Opening an XML file
128   // directly from an ApkAssets has no notion of proper resource references.
129   std::unique_ptr<ResXMLTree> xml_tree = util::make_unique<ResXMLTree>(nullptr /*dynamicRefTable*/);
130   status_t err = xml_tree->setTo(asset->getBuffer(true), asset->getLength(), true);
131   asset.reset();
132 
133   if (err != NO_ERROR) {
134     jniThrowException(env, "java/io/FileNotFoundException", "Corrupt XML binary file");
135     return 0;
136   }
137   return reinterpret_cast<jlong>(xml_tree.release());
138 }
139 
140 // JNI registration.
141 static const JNINativeMethod gApkAssetsMethods[] = {
142     {"nativeLoad", "(Ljava/lang/String;ZZZ)J", (void*)NativeLoad},
143     {"nativeLoadFromFd", "(Ljava/io/FileDescriptor;Ljava/lang/String;ZZ)J",
144         (void*)NativeLoadFromFd},
145     {"nativeDestroy", "(J)V", (void*)NativeDestroy},
146     {"nativeGetAssetPath", "(J)Ljava/lang/String;", (void*)NativeGetAssetPath},
147     {"nativeGetStringBlock", "(J)J", (void*)NativeGetStringBlock},
148     {"nativeIsUpToDate", "(J)Z", (void*)NativeIsUpToDate},
149     {"nativeOpenXml", "(JLjava/lang/String;)J", (void*)NativeOpenXml},
150 };
151 
register_android_content_res_ApkAssets(JNIEnv * env)152 int register_android_content_res_ApkAssets(JNIEnv* env) {
153   return RegisterMethodsOrDie(env, "android/content/res/ApkAssets", gApkAssetsMethods,
154                               arraysize(gApkAssetsMethods));
155 }
156 
157 }  // namespace android
158