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 return LoadImpl({} /*fd*/, loaded_idmap->OverlayApkPath(), std::move(idmap_asset),
74 std::move(loaded_idmap), system, false /*load_as_shared_library*/);
75 }
76
LoadFromFd(unique_fd fd,const std::string & friendly_name,bool system,bool force_shared_lib)77 std::unique_ptr<const ApkAssets> ApkAssets::LoadFromFd(unique_fd fd,
78 const std::string& friendly_name,
79 bool system, bool force_shared_lib) {
80 return LoadImpl(std::move(fd), friendly_name, nullptr /*idmap_asset*/, nullptr /*loaded_idmap*/,
81 system, force_shared_lib);
82 }
83
CreateAssetFromFile(const std::string & path)84 std::unique_ptr<Asset> ApkAssets::CreateAssetFromFile(const std::string& path) {
85 unique_fd fd(base::utf8::open(path.c_str(), O_RDONLY | O_BINARY | O_CLOEXEC));
86 if (fd == -1) {
87 LOG(ERROR) << "Failed to open file '" << path << "': " << SystemErrorCodeToString(errno);
88 return {};
89 }
90
91 const off64_t file_len = lseek64(fd, 0, SEEK_END);
92 if (file_len < 0) {
93 LOG(ERROR) << "Failed to get size of file '" << path << "': " << SystemErrorCodeToString(errno);
94 return {};
95 }
96
97 std::unique_ptr<FileMap> file_map = util::make_unique<FileMap>();
98 if (!file_map->create(path.c_str(), fd, 0, static_cast<size_t>(file_len), true /*readOnly*/)) {
99 LOG(ERROR) << "Failed to mmap file '" << path << "': " << SystemErrorCodeToString(errno);
100 return {};
101 }
102 return Asset::createFromUncompressedMap(std::move(file_map), Asset::AccessMode::ACCESS_RANDOM);
103 }
104
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)105 std::unique_ptr<const ApkAssets> ApkAssets::LoadImpl(
106 unique_fd fd, const std::string& path, std::unique_ptr<Asset> idmap_asset,
107 std::unique_ptr<const LoadedIdmap> loaded_idmap, bool system, bool load_as_shared_library) {
108 ::ZipArchiveHandle unmanaged_handle;
109 int32_t result;
110 if (fd >= 0) {
111 result =
112 ::OpenArchiveFd(fd.release(), path.c_str(), &unmanaged_handle, true /*assume_ownership*/);
113 } else {
114 result = ::OpenArchive(path.c_str(), &unmanaged_handle);
115 }
116
117 if (result != 0) {
118 LOG(ERROR) << "Failed to open APK '" << path << "' " << ::ErrorCodeString(result);
119 return {};
120 }
121
122 time_t last_mod_time = getFileModDate(path.c_str());
123
124 // Wrap the handle in a unique_ptr so it gets automatically closed.
125 std::unique_ptr<ApkAssets> loaded_apk(new ApkAssets(unmanaged_handle, path, last_mod_time));
126
127 // Find the resource table.
128 ::ZipString entry_name(kResourcesArsc.c_str());
129 ::ZipEntry entry;
130 result = ::FindEntry(loaded_apk->zip_handle_.get(), entry_name, &entry);
131 if (result != 0) {
132 // There is no resources.arsc, so create an empty LoadedArsc and return.
133 loaded_apk->loaded_arsc_ = LoadedArsc::CreateEmpty();
134 return std::move(loaded_apk);
135 }
136
137 if (entry.method == kCompressDeflated) {
138 LOG(WARNING) << kResourcesArsc << " in APK '" << path << "' is compressed.";
139 }
140
141 // Open the resource table via mmap unless it is compressed. This logic is taken care of by Open.
142 loaded_apk->resources_asset_ = loaded_apk->Open(kResourcesArsc, Asset::AccessMode::ACCESS_BUFFER);
143 if (loaded_apk->resources_asset_ == nullptr) {
144 LOG(ERROR) << "Failed to open '" << kResourcesArsc << "' in APK '" << path << "'.";
145 return {};
146 }
147
148 // Must retain ownership of the IDMAP Asset so that all pointers to its mmapped data remain valid.
149 loaded_apk->idmap_asset_ = std::move(idmap_asset);
150
151 const StringPiece data(
152 reinterpret_cast<const char*>(loaded_apk->resources_asset_->getBuffer(true /*wordAligned*/)),
153 loaded_apk->resources_asset_->getLength());
154 loaded_apk->loaded_arsc_ =
155 LoadedArsc::Load(data, loaded_idmap.get(), system, load_as_shared_library);
156 if (loaded_apk->loaded_arsc_ == nullptr) {
157 LOG(ERROR) << "Failed to load '" << kResourcesArsc << "' in APK '" << path << "'.";
158 return {};
159 }
160
161 // Need to force a move for mingw32.
162 return std::move(loaded_apk);
163 }
164
Open(const std::string & path,Asset::AccessMode mode) const165 std::unique_ptr<Asset> ApkAssets::Open(const std::string& path, Asset::AccessMode mode) const {
166 CHECK(zip_handle_ != nullptr);
167
168 ::ZipString name(path.c_str());
169 ::ZipEntry entry;
170 int32_t result = ::FindEntry(zip_handle_.get(), name, &entry);
171 if (result != 0) {
172 return {};
173 }
174
175 if (entry.method == kCompressDeflated) {
176 std::unique_ptr<FileMap> map = util::make_unique<FileMap>();
177 if (!map->create(path_.c_str(), ::GetFileDescriptor(zip_handle_.get()), entry.offset,
178 entry.compressed_length, true /*readOnly*/)) {
179 LOG(ERROR) << "Failed to mmap file '" << path << "' in APK '" << path_ << "'";
180 return {};
181 }
182
183 std::unique_ptr<Asset> asset =
184 Asset::createFromCompressedMap(std::move(map), entry.uncompressed_length, mode);
185 if (asset == nullptr) {
186 LOG(ERROR) << "Failed to decompress '" << path << "'.";
187 return {};
188 }
189 return asset;
190 } else {
191 std::unique_ptr<FileMap> map = util::make_unique<FileMap>();
192 if (!map->create(path_.c_str(), ::GetFileDescriptor(zip_handle_.get()), entry.offset,
193 entry.uncompressed_length, true /*readOnly*/)) {
194 LOG(ERROR) << "Failed to mmap file '" << path << "' in APK '" << path_ << "'";
195 return {};
196 }
197
198 std::unique_ptr<Asset> asset = Asset::createFromUncompressedMap(std::move(map), mode);
199 if (asset == nullptr) {
200 LOG(ERROR) << "Failed to mmap file '" << path << "' in APK '" << path_ << "'";
201 return {};
202 }
203 return asset;
204 }
205 }
206
ForEachFile(const std::string & root_path,const std::function<void (const StringPiece &,FileType)> & f) const207 bool ApkAssets::ForEachFile(const std::string& root_path,
208 const std::function<void(const StringPiece&, FileType)>& f) const {
209 CHECK(zip_handle_ != nullptr);
210
211 std::string root_path_full = root_path;
212 if (root_path_full.back() != '/') {
213 root_path_full += '/';
214 }
215
216 ::ZipString prefix(root_path_full.c_str());
217 void* cookie;
218 if (::StartIteration(zip_handle_.get(), &cookie, &prefix, nullptr) != 0) {
219 return false;
220 }
221
222 ::ZipString 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(reinterpret_cast<const char*>(name.name), name.name_length);
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