1 /* 2 * Copyright (C) 2011 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 android.os; 18 19 import android.annotation.AppIdInt; 20 import android.annotation.SystemApi; 21 import android.annotation.TestApi; 22 import android.annotation.UserIdInt; 23 24 import java.io.PrintWriter; 25 26 /** 27 * Representation of a user on the device. 28 */ 29 public final class UserHandle implements Parcelable { 30 // NOTE: keep logic in sync with system/core/libcutils/multiuser.c 31 32 /** 33 * @hide Range of uids allocated for a user. 34 */ 35 public static final int PER_USER_RANGE = 100000; 36 37 /** @hide A user id to indicate all users on the device */ 38 public static final @UserIdInt int USER_ALL = -1; 39 40 /** @hide A user handle to indicate all users on the device */ 41 public static final UserHandle ALL = new UserHandle(USER_ALL); 42 43 /** @hide A user id to indicate the currently active user */ 44 public static final @UserIdInt int USER_CURRENT = -2; 45 46 /** @hide A user handle to indicate the current user of the device */ 47 public static final UserHandle CURRENT = new UserHandle(USER_CURRENT); 48 49 /** @hide A user id to indicate that we would like to send to the current 50 * user, but if this is calling from a user process then we will send it 51 * to the caller's user instead of failing with a security exception */ 52 public static final @UserIdInt int USER_CURRENT_OR_SELF = -3; 53 54 /** @hide A user handle to indicate that we would like to send to the current 55 * user, but if this is calling from a user process then we will send it 56 * to the caller's user instead of failing with a security exception */ 57 public static final UserHandle CURRENT_OR_SELF = new UserHandle(USER_CURRENT_OR_SELF); 58 59 /** @hide An undefined user id */ 60 public static final @UserIdInt int USER_NULL = -10000; 61 62 /** 63 * @hide A user id constant to indicate the "owner" user of the device 64 * @deprecated Consider using either {@link UserHandle#USER_SYSTEM} constant or 65 * check the target user's flag {@link android.content.pm.UserInfo#isAdmin}. 66 */ 67 @Deprecated 68 public static final @UserIdInt int USER_OWNER = 0; 69 70 /** 71 * @hide A user handle to indicate the primary/owner user of the device 72 * @deprecated Consider using either {@link UserHandle#SYSTEM} constant or 73 * check the target user's flag {@link android.content.pm.UserInfo#isAdmin}. 74 */ 75 @Deprecated 76 public static final UserHandle OWNER = new UserHandle(USER_OWNER); 77 78 /** @hide A user id constant to indicate the "system" user of the device */ 79 public static final @UserIdInt int USER_SYSTEM = 0; 80 81 /** @hide A user serial constant to indicate the "system" user of the device */ 82 public static final int USER_SERIAL_SYSTEM = 0; 83 84 /** @hide A user handle to indicate the "system" user of the device */ 85 @TestApi 86 public static final UserHandle SYSTEM = new UserHandle(USER_SYSTEM); 87 88 /** 89 * @hide Enable multi-user related side effects. Set this to false if 90 * there are problems with single user use-cases. 91 */ 92 public static final boolean MU_ENABLED = true; 93 94 /** @hide */ 95 public static final int ERR_GID = -1; 96 /** @hide */ 97 public static final int AID_ROOT = android.os.Process.ROOT_UID; 98 /** @hide */ 99 public static final int AID_APP_START = android.os.Process.FIRST_APPLICATION_UID; 100 /** @hide */ 101 public static final int AID_APP_END = android.os.Process.LAST_APPLICATION_UID; 102 /** @hide */ 103 public static final int AID_SHARED_GID_START = android.os.Process.FIRST_SHARED_APPLICATION_GID; 104 /** @hide */ 105 public static final int AID_CACHE_GID_START = android.os.Process.FIRST_APPLICATION_CACHE_GID; 106 107 final int mHandle; 108 109 /** 110 * Checks to see if the user id is the same for the two uids, i.e., they belong to the same 111 * user. 112 * @hide 113 */ 114 public static boolean isSameUser(int uid1, int uid2) { 115 return getUserId(uid1) == getUserId(uid2); 116 } 117 118 /** 119 * Checks to see if both uids are referring to the same app id, ignoring the user id part of the 120 * uids. 121 * @param uid1 uid to compare 122 * @param uid2 other uid to compare 123 * @return whether the appId is the same for both uids 124 * @hide 125 */ 126 public static boolean isSameApp(int uid1, int uid2) { 127 return getAppId(uid1) == getAppId(uid2); 128 } 129 130 /** 131 * Whether a UID is an "isolated" UID. 132 * @hide 133 */ 134 public static boolean isIsolated(int uid) { 135 if (uid > 0) { 136 final int appId = getAppId(uid); 137 return appId >= Process.FIRST_ISOLATED_UID && appId <= Process.LAST_ISOLATED_UID; 138 } else { 139 return false; 140 } 141 } 142 143 /** 144 * Whether a UID belongs to a regular app. *Note* "Not a regular app" does not mean 145 * "it's system", because of isolated UIDs. Use {@link #isCore} for that. 146 * @hide 147 */ 148 public static boolean isApp(int uid) { 149 if (uid > 0) { 150 final int appId = getAppId(uid); 151 return appId >= Process.FIRST_APPLICATION_UID && appId <= Process.LAST_APPLICATION_UID; 152 } else { 153 return false; 154 } 155 } 156 157 /** 158 * Whether a UID belongs to a system core component or not. 159 * @hide 160 */ 161 public static boolean isCore(int uid) { 162 if (uid >= 0) { 163 final int appId = getAppId(uid); 164 return appId < Process.FIRST_APPLICATION_UID; 165 } else { 166 return false; 167 } 168 } 169 170 /** 171 * Returns the user for a given uid. 172 * @param uid A uid for an application running in a particular user. 173 * @return A {@link UserHandle} for that user. 174 */ 175 public static UserHandle getUserHandleForUid(int uid) { 176 return of(getUserId(uid)); 177 } 178 179 /** 180 * Returns the user id for a given uid. 181 * @hide 182 */ 183 public static @UserIdInt int getUserId(int uid) { 184 if (MU_ENABLED) { 185 return uid / PER_USER_RANGE; 186 } else { 187 return UserHandle.USER_SYSTEM; 188 } 189 } 190 191 /** @hide */ 192 public static @UserIdInt int getCallingUserId() { 193 return getUserId(Binder.getCallingUid()); 194 } 195 196 /** @hide */ 197 public static @AppIdInt int getCallingAppId() { 198 return getAppId(Binder.getCallingUid()); 199 } 200 201 /** @hide */ 202 @SystemApi 203 public static UserHandle of(@UserIdInt int userId) { 204 return userId == USER_SYSTEM ? SYSTEM : new UserHandle(userId); 205 } 206 207 /** 208 * Returns the uid that is composed from the userId and the appId. 209 * @hide 210 */ 211 public static int getUid(@UserIdInt int userId, @AppIdInt int appId) { 212 if (MU_ENABLED) { 213 return userId * PER_USER_RANGE + (appId % PER_USER_RANGE); 214 } else { 215 return appId; 216 } 217 } 218 219 /** 220 * Returns the app id (or base uid) for a given uid, stripping out the user id from it. 221 * @hide 222 */ 223 @TestApi 224 public static @AppIdInt int getAppId(int uid) { 225 return uid % PER_USER_RANGE; 226 } 227 228 /** 229 * Returns the gid shared between all apps with this userId. 230 * @hide 231 */ 232 public static int getUserGid(@UserIdInt int userId) { 233 return getUid(userId, Process.SHARED_USER_GID); 234 } 235 236 /** @hide */ 237 public static int getSharedAppGid(int uid) { 238 return getSharedAppGid(getUserId(uid), getAppId(uid)); 239 } 240 241 /** @hide */ 242 public static int getSharedAppGid(int userId, int appId) { 243 if (appId >= AID_APP_START && appId <= AID_APP_END) { 244 return (appId - AID_APP_START) + AID_SHARED_GID_START; 245 } else if (appId >= AID_ROOT && appId <= AID_APP_START) { 246 return appId; 247 } else { 248 return -1; 249 } 250 } 251 252 /** 253 * Returns the app id for a given shared app gid. Returns -1 if the ID is invalid. 254 * @hide 255 */ 256 public static @AppIdInt int getAppIdFromSharedAppGid(int gid) { 257 final int appId = getAppId(gid) + Process.FIRST_APPLICATION_UID 258 - Process.FIRST_SHARED_APPLICATION_GID; 259 if (appId < 0 || appId >= Process.FIRST_SHARED_APPLICATION_GID) { 260 return -1; 261 } 262 return appId; 263 } 264 265 /** @hide */ 266 public static int getCacheAppGid(int uid) { 267 return getCacheAppGid(getUserId(uid), getAppId(uid)); 268 } 269 270 /** @hide */ 271 public static int getCacheAppGid(int userId, int appId) { 272 if (appId >= AID_APP_START && appId <= AID_APP_END) { 273 return getUid(userId, (appId - AID_APP_START) + AID_CACHE_GID_START); 274 } else { 275 return -1; 276 } 277 } 278 279 /** 280 * Generate a text representation of the uid, breaking out its individual 281 * components -- user, app, isolated, etc. 282 * @hide 283 */ 284 public static void formatUid(StringBuilder sb, int uid) { 285 if (uid < Process.FIRST_APPLICATION_UID) { 286 sb.append(uid); 287 } else { 288 sb.append('u'); 289 sb.append(getUserId(uid)); 290 final int appId = getAppId(uid); 291 if (appId >= Process.FIRST_ISOLATED_UID && appId <= Process.LAST_ISOLATED_UID) { 292 sb.append('i'); 293 sb.append(appId - Process.FIRST_ISOLATED_UID); 294 } else if (appId >= Process.FIRST_APPLICATION_UID) { 295 sb.append('a'); 296 sb.append(appId - Process.FIRST_APPLICATION_UID); 297 } else { 298 sb.append('s'); 299 sb.append(appId); 300 } 301 } 302 } 303 304 /** 305 * Generate a text representation of the uid, breaking out its individual 306 * components -- user, app, isolated, etc. 307 * @hide 308 */ 309 public static String formatUid(int uid) { 310 StringBuilder sb = new StringBuilder(); 311 formatUid(sb, uid); 312 return sb.toString(); 313 } 314 315 /** 316 * Generate a text representation of the uid, breaking out its individual 317 * components -- user, app, isolated, etc. 318 * @hide 319 */ 320 public static void formatUid(PrintWriter pw, int uid) { 321 if (uid < Process.FIRST_APPLICATION_UID) { 322 pw.print(uid); 323 } else { 324 pw.print('u'); 325 pw.print(getUserId(uid)); 326 final int appId = getAppId(uid); 327 if (appId >= Process.FIRST_ISOLATED_UID && appId <= Process.LAST_ISOLATED_UID) { 328 pw.print('i'); 329 pw.print(appId - Process.FIRST_ISOLATED_UID); 330 } else if (appId >= Process.FIRST_APPLICATION_UID) { 331 pw.print('a'); 332 pw.print(appId - Process.FIRST_APPLICATION_UID); 333 } else { 334 pw.print('s'); 335 pw.print(appId); 336 } 337 } 338 } 339 340 /** @hide */ 341 public static @UserIdInt int parseUserArg(String arg) { 342 int userId; 343 if ("all".equals(arg)) { 344 userId = UserHandle.USER_ALL; 345 } else if ("current".equals(arg) || "cur".equals(arg)) { 346 userId = UserHandle.USER_CURRENT; 347 } else { 348 try { 349 userId = Integer.parseInt(arg); 350 } catch (NumberFormatException e) { 351 throw new IllegalArgumentException("Bad user number: " + arg); 352 } 353 } 354 return userId; 355 } 356 357 /** 358 * Returns the user id of the current process 359 * @return user id of the current process 360 * @hide 361 */ 362 @SystemApi 363 public static @UserIdInt int myUserId() { 364 return getUserId(Process.myUid()); 365 } 366 367 /** 368 * Returns true if this UserHandle refers to the owner user; false otherwise. 369 * @return true if this UserHandle refers to the owner user; false otherwise. 370 * @hide 371 * @deprecated please use {@link #isSystem()} or check for 372 * {@link android.content.pm.UserInfo#isPrimary()} 373 * {@link android.content.pm.UserInfo#isAdmin()} based on your particular use case. 374 */ 375 @Deprecated 376 @SystemApi 377 public boolean isOwner() { 378 return this.equals(OWNER); 379 } 380 381 /** 382 * @return true if this UserHandle refers to the system user; false otherwise. 383 * @hide 384 */ 385 @SystemApi 386 public boolean isSystem() { 387 return this.equals(SYSTEM); 388 } 389 390 /** @hide */ 391 public UserHandle(int h) { 392 mHandle = h; 393 } 394 395 /** 396 * Returns the userId stored in this UserHandle. 397 * @hide 398 */ 399 @SystemApi 400 @TestApi 401 public @UserIdInt int getIdentifier() { 402 return mHandle; 403 } 404 405 @Override 406 public String toString() { 407 return "UserHandle{" + mHandle + "}"; 408 } 409 410 @Override 411 public boolean equals(Object obj) { 412 try { 413 if (obj != null) { 414 UserHandle other = (UserHandle)obj; 415 return mHandle == other.mHandle; 416 } 417 } catch (ClassCastException e) { 418 } 419 return false; 420 } 421 422 @Override 423 public int hashCode() { 424 return mHandle; 425 } 426 427 public int describeContents() { 428 return 0; 429 } 430 431 public void writeToParcel(Parcel out, int flags) { 432 out.writeInt(mHandle); 433 } 434 435 /** 436 * Write a UserHandle to a Parcel, handling null pointers. Must be 437 * read with {@link #readFromParcel(Parcel)}. 438 * 439 * @param h The UserHandle to be written. 440 * @param out The Parcel in which the UserHandle will be placed. 441 * 442 * @see #readFromParcel(Parcel) 443 */ 444 public static void writeToParcel(UserHandle h, Parcel out) { 445 if (h != null) { 446 h.writeToParcel(out, 0); 447 } else { 448 out.writeInt(USER_NULL); 449 } 450 } 451 452 /** 453 * Read a UserHandle from a Parcel that was previously written 454 * with {@link #writeToParcel(UserHandle, Parcel)}, returning either 455 * a null or new object as appropriate. 456 * 457 * @param in The Parcel from which to read the UserHandle 458 * @return Returns a new UserHandle matching the previously written 459 * object, or null if a null had been written. 460 * 461 * @see #writeToParcel(UserHandle, Parcel) 462 */ 463 public static UserHandle readFromParcel(Parcel in) { 464 int h = in.readInt(); 465 return h != USER_NULL ? new UserHandle(h) : null; 466 } 467 468 public static final Parcelable.Creator<UserHandle> CREATOR 469 = new Parcelable.Creator<UserHandle>() { 470 public UserHandle createFromParcel(Parcel in) { 471 return new UserHandle(in); 472 } 473 474 public UserHandle[] newArray(int size) { 475 return new UserHandle[size]; 476 } 477 }; 478 479 /** 480 * Instantiate a new UserHandle from the data in a Parcel that was 481 * previously written with {@link #writeToParcel(Parcel, int)}. Note that you 482 * must not use this with data written by 483 * {@link #writeToParcel(UserHandle, Parcel)} since it is not possible 484 * to handle a null UserHandle here. 485 * 486 * @param in The Parcel containing the previously written UserHandle, 487 * positioned at the location in the buffer where it was written. 488 */ 489 public UserHandle(Parcel in) { 490 mHandle = in.readInt(); 491 } 492 } 493
