Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2018 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 | package com.android.server.role; |
| 18 | |
| 19 | import android.annotation.CheckResult; |
| 20 | import android.annotation.NonNull; |
| 21 | import android.annotation.Nullable; |
| 22 | import android.annotation.UserIdInt; |
| 23 | import android.annotation.WorkerThread; |
| 24 | import android.os.Environment; |
| 25 | import android.os.Handler; |
| 26 | import android.util.ArrayMap; |
| 27 | import android.util.ArraySet; |
| 28 | import android.util.AtomicFile; |
| 29 | import android.util.Slog; |
| 30 | import android.util.Xml; |
| 31 | |
| 32 | import com.android.internal.annotations.GuardedBy; |
| 33 | import com.android.internal.os.BackgroundThread; |
| 34 | import com.android.internal.util.function.pooled.PooledLambda; |
| 35 | |
| 36 | import libcore.io.IoUtils; |
| 37 | |
| 38 | import org.xmlpull.v1.XmlPullParser; |
| 39 | import org.xmlpull.v1.XmlPullParserException; |
| 40 | import org.xmlpull.v1.XmlSerializer; |
| 41 | |
| 42 | import java.io.File; |
| 43 | import java.io.FileInputStream; |
| 44 | import java.io.FileNotFoundException; |
| 45 | import java.io.FileOutputStream; |
| 46 | import java.io.IOException; |
| 47 | import java.nio.charset.StandardCharsets; |
| 48 | |
| 49 | /** |
| 50 | * Stores the state of roles for a user. |
| 51 | */ |
| 52 | public class RoleUserState { |
| 53 | |
| 54 | private static final String LOG_TAG = RoleUserState.class.getSimpleName(); |
| 55 | |
| 56 | public static final int VERSION_UNDEFINED = -1; |
| 57 | |
| 58 | private static final String ROLES_FILE_NAME = "roles.xml"; |
| 59 | |
| 60 | private static final String TAG_ROLES = "roles"; |
| 61 | private static final String TAG_ROLE = "role"; |
| 62 | private static final String TAG_HOLDER = "holder"; |
| 63 | private static final String ATTRIBUTE_VERSION = "version"; |
| 64 | private static final String ATTRIBUTE_NAME = "name"; |
| 65 | |
| 66 | @UserIdInt |
| 67 | private final int mUserId; |
| 68 | |
| 69 | @GuardedBy("RoleManagerService.mLock") |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 70 | private int mVersion; |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 71 | |
| 72 | /** |
| 73 | * Maps role names to its holders' package names. The values should never be null. |
| 74 | */ |
| 75 | @GuardedBy("RoleManagerService.mLock") |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 76 | private ArrayMap<String, ArraySet<String>> mRoles; |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 77 | |
| 78 | @GuardedBy("RoleManagerService.mLock") |
| 79 | private boolean mDestroyed; |
| 80 | |
| 81 | private final Handler mWriteHandler = new Handler(BackgroundThread.getHandler().getLooper()); |
| 82 | |
| 83 | public RoleUserState(@UserIdInt int userId) { |
| 84 | mUserId = userId; |
| 85 | } |
| 86 | |
| 87 | /** |
| 88 | * Get the version of this user state. |
| 89 | */ |
| 90 | @GuardedBy("RoleManagerService.mLock") |
| 91 | public int getVersionLocked() { |
| 92 | throwIfDestroyedLocked(); |
| 93 | return mVersion; |
| 94 | } |
| 95 | |
| 96 | /** |
| 97 | * Set the version of this user state. |
| 98 | * |
| 99 | * @param version the version to set |
| 100 | */ |
| 101 | @GuardedBy("RoleManagerService.mLock") |
| 102 | public void setVersionLocked(int version) { |
| 103 | throwIfDestroyedLocked(); |
| 104 | mVersion = version; |
| 105 | } |
| 106 | |
| 107 | /** |
| 108 | * Get whether the role is available. |
| 109 | * |
| 110 | * @param roleName the name of the role to get the holders for |
| 111 | * |
| 112 | * @return whether the role is available |
| 113 | */ |
| 114 | @GuardedBy("RoleManagerService.mLock") |
| 115 | public boolean isRoleAvailableLocked(@NonNull String roleName) { |
| 116 | throwIfDestroyedLocked(); |
| 117 | return mRoles.containsKey(roleName); |
| 118 | } |
| 119 | |
| 120 | /** |
| 121 | * Get the holders of a role. |
| 122 | * |
| 123 | * @param roleName the name of the role to query for |
| 124 | * |
| 125 | * @return the set of role holders. {@code null} should not be returned and indicates an issue. |
| 126 | */ |
| 127 | @GuardedBy("RoleManagerService.mLock") |
| 128 | @Nullable |
| 129 | public ArraySet<String> getRoleHoldersLocked(@NonNull String roleName) { |
| 130 | throwIfDestroyedLocked(); |
| 131 | return mRoles.get(roleName); |
| 132 | } |
| 133 | |
| 134 | /** |
| 135 | * Add a holder to a role. |
| 136 | * |
| 137 | * @param roleName the name of the role to add the holder to |
| 138 | * @param packageName the package name of the new holder |
| 139 | * |
| 140 | * @return {@code false} only if the set of role holders is null, which should not happen and |
| 141 | * indicates an issue. |
| 142 | */ |
| 143 | @CheckResult |
| 144 | @GuardedBy("RoleManagerService.mLock") |
| 145 | public boolean addRoleHolderLocked(@NonNull String roleName, @NonNull String packageName) { |
| 146 | throwIfDestroyedLocked(); |
| 147 | ArraySet<String> roleHolders = mRoles.get(roleName); |
| 148 | if (roleHolders == null) { |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 149 | Slog.e(LOG_TAG, "Cannot add role holder for unknown role, role: " + roleName |
| 150 | + ", package: " + packageName); |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 151 | return false; |
| 152 | } |
| 153 | roleHolders.add(packageName); |
| 154 | return true; |
| 155 | } |
| 156 | |
| 157 | /** |
| 158 | * Remove a holder from a role. |
| 159 | * |
| 160 | * @param roleName the name of the role to remove the holder from |
| 161 | * @param packageName the package name of the holder to remove |
| 162 | * |
| 163 | * @return {@code false} only if the set of role holders is null, which should not happen and |
| 164 | * indicates an issue. |
| 165 | */ |
| 166 | @CheckResult |
| 167 | @GuardedBy("RoleManagerService.mLock") |
| 168 | public boolean removeRoleHolderLocked(@NonNull String roleName, @NonNull String packageName) { |
| 169 | throwIfDestroyedLocked(); |
| 170 | ArraySet<String> roleHolders = mRoles.get(roleName); |
| 171 | if (roleHolders == null) { |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 172 | Slog.e(LOG_TAG, "Cannot remove role holder for unknown role, role: " + roleName |
| 173 | + ", package: " + packageName); |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 174 | return false; |
| 175 | } |
| 176 | roleHolders.remove(packageName); |
| 177 | return true; |
| 178 | } |
| 179 | |
| 180 | /** |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 181 | * Schedule writing the state to file. |
| 182 | */ |
| 183 | @GuardedBy("RoleManagerService.mLock") |
| 184 | public void writeAsyncLocked() { |
| 185 | throwIfDestroyedLocked(); |
| 186 | int version = mVersion; |
| 187 | ArrayMap<String, ArraySet<String>> roles = new ArrayMap<>(); |
| 188 | for (int i = 0, size = mRoles.size(); i < size; ++i) { |
| 189 | String roleName = mRoles.keyAt(i); |
| 190 | ArraySet<String> roleHolders = mRoles.valueAt(i); |
| 191 | roleHolders = new ArraySet<>(roleHolders); |
| 192 | roles.put(roleName, roleHolders); |
| 193 | } |
| 194 | mWriteHandler.removeCallbacksAndMessages(null); |
Eugene Susla | 6d492272 | 2018-11-08 16:25:28 -0800 | [diff] [blame] | 195 | mWriteHandler.sendMessage(PooledLambda.obtainMessage( |
| 196 | RoleUserState::writeSync, this, version, roles)); |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 197 | } |
| 198 | |
| 199 | @WorkerThread |
| 200 | private void writeSync(int version, @NonNull ArrayMap<String, ArraySet<String>> roles) { |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 201 | AtomicFile atomicFile = new AtomicFile(getFile(mUserId), "roles-" + mUserId); |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 202 | FileOutputStream out = null; |
| 203 | try { |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 204 | out = atomicFile.startWrite(); |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 205 | |
| 206 | XmlSerializer serializer = Xml.newSerializer(); |
| 207 | serializer.setOutput(out, StandardCharsets.UTF_8.name()); |
| 208 | serializer.setFeature( |
| 209 | "http://xmlpull.org/v1/doc/features.html#indent-output", true); |
| 210 | serializer.startDocument(null, true); |
| 211 | |
| 212 | serializeRoles(serializer, version, roles); |
| 213 | |
| 214 | serializer.endDocument(); |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 215 | atomicFile.finishWrite(out); |
| 216 | } catch (IllegalArgumentException | IllegalStateException | IOException e) { |
| 217 | Slog.wtf(LOG_TAG, "Failed to write roles.xml, restoring backup", e); |
| 218 | if (out != null) { |
| 219 | atomicFile.failWrite(out); |
| 220 | } |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 221 | } finally { |
| 222 | IoUtils.closeQuietly(out); |
| 223 | } |
| 224 | } |
| 225 | |
| 226 | @WorkerThread |
| 227 | private void serializeRoles(@NonNull XmlSerializer serializer, int version, |
| 228 | @NonNull ArrayMap<String, ArraySet<String>> roles) throws IOException { |
| 229 | serializer.startTag(null, TAG_ROLES); |
| 230 | serializer.attribute(null, ATTRIBUTE_VERSION, Integer.toString(version)); |
| 231 | for (int i = 0, size = roles.size(); i < size; ++i) { |
| 232 | String roleName = roles.keyAt(i); |
| 233 | ArraySet<String> roleHolders = roles.valueAt(i); |
| 234 | serializer.startTag(null, TAG_ROLE); |
| 235 | serializer.attribute(null, ATTRIBUTE_NAME, roleName); |
| 236 | serializeRoleHolders(serializer, roleHolders); |
| 237 | serializer.endTag(null, TAG_ROLE); |
| 238 | } |
| 239 | serializer.endTag(null, TAG_ROLES); |
| 240 | } |
| 241 | |
| 242 | @WorkerThread |
| 243 | private void serializeRoleHolders(@NonNull XmlSerializer serializer, |
| 244 | @NonNull ArraySet<String> roleHolders) throws IOException { |
| 245 | for (int i = 0, size = roleHolders.size(); i < size; ++i) { |
| 246 | String roleHolder = roleHolders.valueAt(i); |
| 247 | serializer.startTag(null, TAG_HOLDER); |
| 248 | serializer.attribute(null, ATTRIBUTE_NAME, roleHolder); |
| 249 | serializer.endTag(null, TAG_HOLDER); |
| 250 | } |
| 251 | } |
| 252 | |
| 253 | /** |
| 254 | * Read the state from file. |
| 255 | */ |
| 256 | @GuardedBy("RoleManagerService.mLock") |
| 257 | public void readSyncLocked() { |
| 258 | if (mRoles != null) { |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 259 | throw new IllegalStateException("This RoleUserState has already read the roles.xml"); |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 260 | } |
| 261 | |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 262 | File file = getFile(mUserId); |
| 263 | try (FileInputStream in = new AtomicFile(file).openRead()) { |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 264 | XmlPullParser parser = Xml.newPullParser(); |
| 265 | parser.setInput(in, null); |
| 266 | parseXmlLocked(parser); |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 267 | } catch (FileNotFoundException e) { |
| 268 | Slog.i(LOG_TAG, "roles.xml not found"); |
| 269 | mRoles = new ArrayMap<>(); |
| 270 | mVersion = VERSION_UNDEFINED; |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 271 | } catch (XmlPullParserException | IOException e) { |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 272 | throw new IllegalStateException("Failed to parse roles.xml: " + file, e); |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 273 | } |
| 274 | } |
| 275 | |
| 276 | private void parseXmlLocked(@NonNull XmlPullParser parser) throws IOException, |
| 277 | XmlPullParserException { |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 278 | int type; |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 279 | int depth; |
| 280 | int innerDepth = parser.getDepth() + 1; |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 281 | while ((type = parser.next()) != XmlPullParser.END_DOCUMENT |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 282 | && ((depth = parser.getDepth()) >= innerDepth || type != XmlPullParser.END_TAG)) { |
| 283 | if (depth > innerDepth || type != XmlPullParser.START_TAG) { |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 284 | continue; |
| 285 | } |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 286 | |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 287 | if (parser.getName().equals(TAG_ROLES)) { |
| 288 | parseRolesLocked(parser); |
| 289 | return; |
| 290 | } |
| 291 | } |
| 292 | } |
| 293 | |
| 294 | private void parseRolesLocked(@NonNull XmlPullParser parser) throws IOException, |
| 295 | XmlPullParserException { |
| 296 | mVersion = Integer.parseInt(parser.getAttributeValue(null, ATTRIBUTE_VERSION)); |
| 297 | mRoles = new ArrayMap<>(); |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 298 | |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 299 | int type; |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 300 | int depth; |
| 301 | int innerDepth = parser.getDepth() + 1; |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 302 | while ((type = parser.next()) != XmlPullParser.END_DOCUMENT |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 303 | && ((depth = parser.getDepth()) >= innerDepth || type != XmlPullParser.END_TAG)) { |
| 304 | if (depth > innerDepth || type != XmlPullParser.START_TAG) { |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 305 | continue; |
| 306 | } |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 307 | |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 308 | if (parser.getName().equals(TAG_ROLE)) { |
| 309 | String roleName = parser.getAttributeValue(null, ATTRIBUTE_NAME); |
| 310 | ArraySet<String> roleHolders = parseRoleHoldersLocked(parser); |
| 311 | mRoles.put(roleName, roleHolders); |
| 312 | } |
| 313 | } |
| 314 | } |
| 315 | |
| 316 | @NonNull |
| 317 | private ArraySet<String> parseRoleHoldersLocked(@NonNull XmlPullParser parser) |
| 318 | throws IOException, XmlPullParserException { |
| 319 | ArraySet<String> roleHolders = new ArraySet<>(); |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 320 | |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 321 | int type; |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 322 | int depth; |
| 323 | int innerDepth = parser.getDepth() + 1; |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 324 | while ((type = parser.next()) != XmlPullParser.END_DOCUMENT |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 325 | && ((depth = parser.getDepth()) >= innerDepth || type != XmlPullParser.END_TAG)) { |
| 326 | if (depth > innerDepth || type != XmlPullParser.START_TAG) { |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 327 | continue; |
| 328 | } |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 329 | |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 330 | if (parser.getName().equals(TAG_HOLDER)) { |
| 331 | String roleHolder = parser.getAttributeValue(null, ATTRIBUTE_NAME); |
| 332 | roleHolders.add(roleHolder); |
| 333 | } |
| 334 | } |
Hai Zhang | b295ac4 | 2018-11-16 16:08:18 -0800 | [diff] [blame^] | 335 | |
Hai Zhang | b777668 | 2018-09-25 15:10:57 -0700 | [diff] [blame] | 336 | return roleHolders; |
| 337 | } |
| 338 | |
| 339 | /** |
| 340 | * Destroy this state and delete the corresponding file. Any pending writes to the file will be |
| 341 | * cancelled and any future interaction with this state will throw an exception. |
| 342 | */ |
| 343 | @GuardedBy("RoleManagerService.mLock") |
| 344 | public void destroySyncLocked() { |
| 345 | throwIfDestroyedLocked(); |
| 346 | mWriteHandler.removeCallbacksAndMessages(null); |
| 347 | getFile(mUserId).delete(); |
| 348 | mDestroyed = true; |
| 349 | } |
| 350 | |
| 351 | @GuardedBy("RoleManagerService.mLock") |
| 352 | private void throwIfDestroyedLocked() { |
| 353 | if (mDestroyed) { |
| 354 | throw new IllegalStateException("This RoleUserState has already been destroyed"); |
| 355 | } |
| 356 | } |
| 357 | |
| 358 | private static @NonNull File getFile(@UserIdInt int userId) { |
| 359 | return new File(Environment.getUserSystemDirectory(userId), ROLES_FILE_NAME); |
| 360 | } |
| 361 | } |