1 /*
2 * Copyright (C) 2016 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 "androidfw/ApkAssets.h"
18
19 #include <algorithm>
20
21 #include "android-base/errors.h"
22 #include "android-base/file.h"
23 #include "android-base/logging.h"
24 #include "android-base/unique_fd.h"
25 #include "android-base/utf8.h"
26 #include "utils/Compat.h"
27 #include "utils/FileMap.h"
28 #include "ziparchive/zip_archive.h"
29
30 #include "androidfw/Asset.h"
31 #include "androidfw/Idmap.h"
32 #include "androidfw/misc.h"
33 #include "androidfw/ResourceTypes.h"
34 #include "androidfw/Util.h"
35
36 namespace android {
37
38 using base::SystemErrorCodeToString;
39 using base::unique_fd;
40
41 static const std::string kResourcesArsc("resources.arsc");
42
ApkAssets(ZipArchiveHandle unmanaged_handle,const std::string & path,time_t last_mod_time)43 ApkAssets::ApkAssets(ZipArchiveHandle unmanaged_handle,
44 const std::string& path,
45 time_t last_mod_time)
46 : zip_handle_(unmanaged_handle, ::CloseArchive), path_(path), last_mod_time_(last_mod_time) {
47 }
48
Load(const std::string & path,bool system)49 std::unique_ptr<const ApkAssets> ApkAssets::Load(const std::string& path, bool system) {
50 return LoadImpl({} /*fd*/, path, nullptr, nullptr, system, false /*load_as_shared_library*/);
51 }
52
LoadAsSharedLibrary(const std::string & path,bool system)53 std::unique_ptr<const ApkAssets> ApkAssets::LoadAsSharedLibrary(const std::string& path,
54 bool system) {
55 return LoadImpl({} /*fd*/, path, nullptr, nullptr, system, true /*load_as_shared_library*/);
56 }
57
LoadOverlay(const std::string & idmap_path,bool system)58 std::unique_ptr<const ApkAssets> ApkAssets::LoadOverlay(const std::string& idmap_path,
59 bool system) {
60 std::unique_ptr<Asset> idmap_asset = CreateAssetFromFile(idmap_path);
61 if (idmap_asset == nullptr) {
62 return {};
63 }
64
65 const StringPiece idmap_data(
66 reinterpret_cast<const char*>(idmap_asset->getBuffer(true /*wordAligned*/)),
67 static_cast<size_t>(idmap_asset->getLength()));
68 std::unique_ptr<const LoadedIdmap> loaded_idmap = LoadedIdmap::Load(idmap_data);
69 if (loaded_idmap == nullptr) {
70 LOG(ERROR) << "failed to load IDMAP " << idmap_path;
71 return {};
72 }
73 auto apkPath = loaded_idmap->OverlayApkPath();
74 return LoadImpl({} /*fd*/, apkPath,
75 std::move(idmap_asset),
76 std::move(loaded_idmap),
77 system, false /*load_as_shared_library*/);
78 }
79
LoadFromFd(unique_fd fd,const std::string & friendly_name,bool system,bool force_shared_lib)80 std::unique_ptr<const ApkAssets> ApkAssets::LoadFromFd(unique_fd fd,
81 const std::string& friendly_name,
82 bool system, bool force_shared_lib) {
83 return LoadImpl(std::move(fd), friendly_name, nullptr /*idmap_asset*/, nullptr /*loaded_idmap*/,
84 system, force_shared_lib);
85 }
86
CreateAssetFromFile(const std::string & path)87 std::unique_ptr<Asset> ApkAssets::CreateAssetFromFile(const std::string& path) {
88 unique_fd fd(base::utf8::open(path.c_str(), O_RDONLY | O_BINARY | O_CLOEXEC));
89 if (fd == -1) {
90 LOG(ERROR) << "Failed to open file '" << path << "': " << SystemErrorCodeToString(errno);
91 return {};
92 }
93
94 const off64_t file_len = lseek64(fd, 0, SEEK_END);
95 if (file_len < 0) {
96 LOG(ERROR) << "Failed to get size of file '" << path << "': " << SystemErrorCodeToString(errno);
97 return {};
98 }
99
100 std::unique_ptr<FileMap> file_map = util::make_unique<FileMap>();
101 if (!file_map->create(path.c_str(), fd, 0, static_cast<size_t>(file_len), true /*readOnly*/)) {
102 LOG(ERROR) << "Failed to mmap file '" << path << "': " << SystemErrorCodeToString(errno);
103 return {};
104 }
105 return Asset::createFromUncompressedMap(std::move(file_map), Asset::AccessMode::ACCESS_RANDOM);
106 }
107
LoadImpl(unique_fd fd,const std::string & path,std::unique_ptr<Asset> idmap_asset,std::unique_ptr<const LoadedIdmap> loaded_idmap,bool system,bool load_as_shared_library)108 std::unique_ptr<const ApkAssets> ApkAssets::LoadImpl(
109 unique_fd fd, const std::string& path, std::unique_ptr<Asset> idmap_asset,
110 std::unique_ptr<const LoadedIdmap> loaded_idmap, bool system, bool load_as_shared_library) {
111 ::ZipArchiveHandle unmanaged_handle;
112 int32_t result;
113 if (fd >= 0) {
114 result =
115 ::OpenArchiveFd(fd.release(), path.c_str(), &unmanaged_handle, true /*assume_ownership*/);
116 } else {
117 result = ::OpenArchive(path.c_str(), &unmanaged_handle);
118 }
119
120 if (result != 0) {
121 LOG(ERROR) << "Failed to open APK '" << path << "' " << ::ErrorCodeString(result);
122 return {};
123 }
124
125 time_t last_mod_time = getFileModDate(path.c_str());
126
127 // Wrap the handle in a unique_ptr so it gets automatically closed.
128 std::unique_ptr<ApkAssets> loaded_apk(new ApkAssets(unmanaged_handle, path, last_mod_time));
129
130 // Find the resource table.
131 ::ZipEntry entry;
132 result = ::FindEntry(loaded_apk->zip_handle_.get(), kResourcesArsc, &entry);
133 if (result != 0) {
134 // There is no resources.arsc, so create an empty LoadedArsc and return.
135 loaded_apk->loaded_arsc_ = LoadedArsc::CreateEmpty();
136 return std::move(loaded_apk);
137 }
138
139 if (entry.method == kCompressDeflated) {
140 LOG(WARNING) << kResourcesArsc << " in APK '" << path << "' is compressed.";
141 }
142
143 // Open the resource table via mmap unless it is compressed. This logic is taken care of by Open.
144 loaded_apk->resources_asset_ = loaded_apk->Open(kResourcesArsc, Asset::AccessMode::ACCESS_BUFFER);
145 if (loaded_apk->resources_asset_ == nullptr) {
146 LOG(ERROR) << "Failed to open '" << kResourcesArsc << "' in APK '" << path << "'.";
147 return {};
148 }
149
150 // Must retain ownership of the IDMAP Asset so that all pointers to its mmapped data remain valid.
151 loaded_apk->idmap_asset_ = std::move(idmap_asset);
152
153 const StringPiece data(
154 reinterpret_cast<const char*>(loaded_apk->resources_asset_->getBuffer(true /*wordAligned*/)),
155 loaded_apk->resources_asset_->getLength());
156 loaded_apk->loaded_arsc_ =
157 LoadedArsc::Load(data, loaded_idmap.get(), system, load_as_shared_library);
158 if (loaded_apk->loaded_arsc_ == nullptr) {
159 LOG(ERROR) << "Failed to load '" << kResourcesArsc << "' in APK '" << path << "'.";
160 return {};
161 }
162
163 // Need to force a move for mingw32.
164 return std::move(loaded_apk);
165 }
166
Open(const std::string & path,Asset::AccessMode mode) const167 std::unique_ptr<Asset> ApkAssets::Open(const std::string& path, Asset::AccessMode mode) const {
168 CHECK(zip_handle_ != nullptr);
169
170 ::ZipEntry entry;
171 int32_t result = ::FindEntry(zip_handle_.get(), path, &entry);
172 if (result != 0) {
173 return {};
174 }
175
176 if (entry.method == kCompressDeflated) {
177 std::unique_ptr<FileMap> map = util::make_unique<FileMap>();
178 if (!map->create(path_.c_str(), ::GetFileDescriptor(zip_handle_.get()), entry.offset,
179 entry.compressed_length, true /*readOnly*/)) {
180 LOG(ERROR) << "Failed to mmap file '" << path << "' in APK '" << path_ << "'";
181 return {};
182 }
183
184 std::unique_ptr<Asset> asset =
185 Asset::createFromCompressedMap(std::move(map), entry.uncompressed_length, mode);
186 if (asset == nullptr) {
187 LOG(ERROR) << "Failed to decompress '" << path << "'.";
188 return {};
189 }
190 return asset;
191 } else {
192 std::unique_ptr<FileMap> map = util::make_unique<FileMap>();
193 if (!map->create(path_.c_str(), ::GetFileDescriptor(zip_handle_.get()), entry.offset,
194 entry.uncompressed_length, true /*readOnly*/)) {
195 LOG(ERROR) << "Failed to mmap file '" << path << "' in APK '" << path_ << "'";
196 return {};
197 }
198
199 std::unique_ptr<Asset> asset = Asset::createFromUncompressedMap(std::move(map), mode);
200 if (asset == nullptr) {
201 LOG(ERROR) << "Failed to mmap file '" << path << "' in APK '" << path_ << "'";
202 return {};
203 }
204 return asset;
205 }
206 }
207
ForEachFile(const std::string & root_path,const std::function<void (const StringPiece &,FileType)> & f) const208 bool ApkAssets::ForEachFile(const std::string& root_path,
209 const std::function<void(const StringPiece&, FileType)>& f) const {
210 CHECK(zip_handle_ != nullptr);
211
212 std::string root_path_full = root_path;
213 if (root_path_full.back() != '/') {
214 root_path_full += '/';
215 }
216
217 void* cookie;
218 if (::StartIteration(zip_handle_.get(), &cookie, root_path_full, "") != 0) {
219 return false;
220 }
221
222 std::string name;
223 ::ZipEntry entry;
224
225 // We need to hold back directories because many paths will contain them and we want to only
226 // surface one.
227 std::set<std::string> dirs;
228
229 int32_t result;
230 while ((result = ::Next(cookie, &entry, &name)) == 0) {
231 StringPiece full_file_path(name);
232 StringPiece leaf_file_path = full_file_path.substr(root_path_full.size());
233
234 if (!leaf_file_path.empty()) {
235 auto iter = std::find(leaf_file_path.begin(), leaf_file_path.end(), '/');
236 if (iter != leaf_file_path.end()) {
237 std::string dir =
238 leaf_file_path.substr(0, std::distance(leaf_file_path.begin(), iter)).to_string();
239 dirs.insert(std::move(dir));
240 } else {
241 f(leaf_file_path, kFileTypeRegular);
242 }
243 }
244 }
245 ::EndIteration(cookie);
246
247 // Now present the unique directories.
248 for (const std::string& dir : dirs) {
249 f(dir, kFileTypeDirectory);
250 }
251
252 // -1 is end of iteration, anything else is an error.
253 return result == -1;
254 }
255
IsUpToDate() const256 bool ApkAssets::IsUpToDate() const {
257 return last_mod_time_ == getFileModDate(path_.c_str());
258 }
259
260 } // namespace android
261