1 /* 2 * Copyright (C) 2012 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.internal.util; 18 19 import android.annotation.Nullable; 20 import android.app.AppOpsManager; 21 import android.content.ComponentName; 22 import android.content.Context; 23 import android.content.pm.PackageManager; 24 import android.os.Binder; 25 import android.os.Handler; 26 import android.text.TextUtils; 27 import android.util.Slog; 28 29 import java.io.PrintWriter; 30 import java.io.StringWriter; 31 import java.util.Objects; 32 import java.util.function.Predicate; 33 34 /** 35 * Helper functions for dumping the state of system services. 36 * Test: 37 atest /android/pi-dev/frameworks/base/core/tests/coretests/src/com/android/internal/util/DumpUtilsTest.java 38 */ 39 public final class DumpUtils { 40 private static final String TAG = "DumpUtils"; 41 private static final boolean DEBUG = false; 42 43 private DumpUtils() { 44 } 45 46 /** 47 * Helper for dumping state owned by a handler thread. 48 * 49 * Because the caller might be holding an important lock that the handler is 50 * trying to acquire, we use a short timeout to avoid deadlocks. The process 51 * is inelegant but this function is only used for debugging purposes. 52 */ 53 public static void dumpAsync(Handler handler, final Dump dump, PrintWriter pw, 54 final String prefix, long timeout) { 55 final StringWriter sw = new StringWriter(); 56 if (handler.runWithScissors(new Runnable() { 57 @Override 58 public void run() { 59 PrintWriter lpw = new FastPrintWriter(sw); 60 dump.dump(lpw, prefix); 61 lpw.close(); 62 } 63 }, timeout)) { 64 pw.print(sw.toString()); 65 } else { 66 pw.println("... timed out"); 67 } 68 } 69 70 public interface Dump { 71 void dump(PrintWriter pw, String prefix); 72 } 73 74 private static void logMessage(PrintWriter pw, String msg) { 75 if (DEBUG) Slog.v(TAG, msg); 76 pw.println(msg); 77 } 78 79 /** 80 * Verify that caller holds {@link android.Manifest.permission#DUMP}. 81 * 82 * @return true if access should be granted. 83 * @hide 84 */ 85 public static boolean checkDumpPermission(Context context, String tag, PrintWriter pw) { 86 if (context.checkCallingOrSelfPermission(android.Manifest.permission.DUMP) 87 != PackageManager.PERMISSION_GRANTED) { 88 logMessage(pw, "Permission Denial: can't dump " + tag + " from from pid=" 89 + Binder.getCallingPid() + ", uid=" + Binder.getCallingUid() 90 + " due to missing android.permission.DUMP permission"); 91 return false; 92 } else { 93 return true; 94 } 95 } 96 97 /** 98 * Verify that caller holds 99 * {@link android.Manifest.permission#PACKAGE_USAGE_STATS} and that they 100 * have {@link AppOpsManager#OP_GET_USAGE_STATS} access. 101 * 102 * @return true if access should be granted. 103 * @hide 104 */ 105 public static boolean checkUsageStatsPermission(Context context, String tag, PrintWriter pw) { 106 // System internals always get access 107 final int uid = Binder.getCallingUid(); 108 switch (uid) { 109 case android.os.Process.ROOT_UID: 110 case android.os.Process.SYSTEM_UID: 111 case android.os.Process.SHELL_UID: 112 case android.os.Process.INCIDENTD_UID: 113 return true; 114 } 115 116 // Caller always needs to hold permission 117 if (context.checkCallingOrSelfPermission(android.Manifest.permission.PACKAGE_USAGE_STATS) 118 != PackageManager.PERMISSION_GRANTED) { 119 logMessage(pw, "Permission Denial: can't dump " + tag + " from from pid=" 120 + Binder.getCallingPid() + ", uid=" + Binder.getCallingUid() 121 + " due to missing android.permission.PACKAGE_USAGE_STATS permission"); 122 return false; 123 } 124 125 // And finally, caller needs to have appops access; this is totally 126 // hacky, but it's the easiest way to wire this up without retrofitting 127 // Binder.dump() to pass through package names. 128 final AppOpsManager appOps = context.getSystemService(AppOpsManager.class); 129 final String[] pkgs = context.getPackageManager().getPackagesForUid(uid); 130 if (pkgs != null) { 131 for (String pkg : pkgs) { 132 switch (appOps.noteOpNoThrow(AppOpsManager.OP_GET_USAGE_STATS, uid, pkg)) { 133 case AppOpsManager.MODE_ALLOWED: 134 if (DEBUG) Slog.v(TAG, "Found package " + pkg + " with " 135 + "android:get_usage_stats allowed"); 136 return true; 137 case AppOpsManager.MODE_DEFAULT: 138 if (DEBUG) Slog.v(TAG, "Found package " + pkg + " with " 139 + "android:get_usage_stats default"); 140 return true; 141 } 142 } 143 } 144 145 logMessage(pw, "Permission Denial: can't dump " + tag + " from from pid=" 146 + Binder.getCallingPid() + ", uid=" + Binder.getCallingUid() 147 + " due to android:get_usage_stats app-op not allowed"); 148 return false; 149 } 150 151 /** 152 * Verify that caller holds both {@link android.Manifest.permission#DUMP} 153 * and {@link android.Manifest.permission#PACKAGE_USAGE_STATS}, and that 154 * they have {@link AppOpsManager#OP_GET_USAGE_STATS} access. 155 * 156 * @return true if access should be granted. 157 * @hide 158 */ 159 public static boolean checkDumpAndUsageStatsPermission(Context context, String tag, 160 PrintWriter pw) { 161 return checkDumpPermission(context, tag, pw) && checkUsageStatsPermission(context, tag, pw); 162 } 163 164 /** 165 * Return whether a package name is considered to be part of the platform. 166 * @hide 167 */ 168 public static boolean isPlatformPackage(@Nullable String packageName) { 169 return (packageName != null) 170 && (packageName.equals("android") 171 || packageName.startsWith("android.") 172 || packageName.startsWith("com.android.")); 173 } 174 175 /** 176 * Return whether a package name is considered to be part of the platform. 177 * @hide 178 */ 179 public static boolean isPlatformPackage(@Nullable ComponentName cname) { 180 return (cname != null) && isPlatformPackage(cname.getPackageName()); 181 } 182 183 /** 184 * Return whether a package name is considered to be part of the platform. 185 * @hide 186 */ 187 public static boolean isPlatformPackage(@Nullable ComponentName.WithComponentName wcn) { 188 return (wcn != null) && isPlatformPackage(wcn.getComponentName()); 189 } 190 191 /** 192 * Return whether a package name is NOT considered to be part of the platform. 193 * @hide 194 */ 195 public static boolean isNonPlatformPackage(@Nullable String packageName) { 196 return (packageName != null) && !isPlatformPackage(packageName); 197 } 198 199 /** 200 * Return whether a package name is NOT considered to be part of the platform. 201 * @hide 202 */ 203 public static boolean isNonPlatformPackage(@Nullable ComponentName cname) { 204 return (cname != null) && isNonPlatformPackage(cname.getPackageName()); 205 } 206 207 /** 208 * Return whether a package name is NOT considered to be part of the platform. 209 * @hide 210 */ 211 public static boolean isNonPlatformPackage(@Nullable ComponentName.WithComponentName wcn) { 212 return (wcn != null) && !isPlatformPackage(wcn.getComponentName()); 213 } 214 215 /** 216 * Used for dumping providers and services. Return a predicate for a given filter string. 217 * @hide 218 */ 219 public static <TRec extends ComponentName.WithComponentName> Predicate<TRec> filterRecord( 220 @Nullable String filterString) { 221 222 if (TextUtils.isEmpty(filterString)) { 223 return rec -> false; 224 } 225 226 // Dump all? 227 if ("all".equals(filterString)) { 228 return Objects::nonNull; 229 } 230 231 // Dump all platform? 232 if ("all-platform".equals(filterString)) { 233 return DumpUtils::isPlatformPackage; 234 } 235 236 // Dump all non-platform? 237 if ("all-non-platform".equals(filterString)) { 238 return DumpUtils::isNonPlatformPackage; 239 } 240 241 // Is the filter a component name? If so, do an exact match. 242 final ComponentName filterCname = ComponentName.unflattenFromString(filterString); 243 if (filterCname != null) { 244 // Do exact component name check. 245 return rec -> (rec != null) && filterCname.equals(rec.getComponentName()); 246 } 247 248 // Otherwise, do a partial match against the component name. 249 // Also if the filter is a hex-decimal string, do the object ID match too. 250 final int id = ParseUtils.parseIntWithBase(filterString, 16, -1); 251 return rec -> { 252 final ComponentName cn = rec.getComponentName(); 253 return ((id != -1) && (System.identityHashCode(rec) == id)) 254 || cn.flattenToString().toLowerCase().contains(filterString.toLowerCase()); 255 }; 256 } 257 } 258 259
