Adrian Roos | 82142c2 | 2014-03-27 14:56:59 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2014 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.trust; |
| 18 | |
| 19 | import com.android.internal.content.PackageMonitor; |
| 20 | import com.android.internal.widget.LockPatternUtils; |
| 21 | import com.android.server.SystemService; |
| 22 | |
| 23 | import org.xmlpull.v1.XmlPullParser; |
| 24 | import org.xmlpull.v1.XmlPullParserException; |
| 25 | |
| 26 | import android.Manifest; |
| 27 | import android.app.trust.ITrustListener; |
| 28 | import android.app.trust.ITrustManager; |
| 29 | import android.content.ComponentName; |
| 30 | import android.content.Context; |
| 31 | import android.content.Intent; |
| 32 | import android.content.pm.PackageManager; |
| 33 | import android.content.pm.ResolveInfo; |
| 34 | import android.content.pm.UserInfo; |
| 35 | import android.content.res.Resources; |
| 36 | import android.content.res.TypedArray; |
| 37 | import android.content.res.XmlResourceParser; |
| 38 | import android.graphics.drawable.Drawable; |
| 39 | import android.os.Handler; |
| 40 | import android.os.IBinder; |
| 41 | import android.os.Message; |
| 42 | import android.os.RemoteException; |
| 43 | import android.os.UserHandle; |
| 44 | import android.os.UserManager; |
| 45 | import android.service.trust.TrustAgentService; |
| 46 | import android.util.ArraySet; |
| 47 | import android.util.AttributeSet; |
| 48 | import android.util.Slog; |
| 49 | import android.util.Xml; |
| 50 | |
| 51 | import java.io.IOException; |
| 52 | import java.util.ArrayList; |
| 53 | import java.util.List; |
| 54 | |
| 55 | /** |
| 56 | * Manages trust agents and trust listeners. |
| 57 | * |
| 58 | * It is responsible for binding to the enabled {@link android.service.trust.TrustAgentService}s |
| 59 | * of each user and notifies them about events that are relevant to them. |
| 60 | * It start and stops them based on the value of |
| 61 | * {@link com.android.internal.widget.LockPatternUtils#getEnabledTrustAgents(int)}. |
| 62 | * |
| 63 | * It also keeps a set of {@link android.app.trust.ITrustListener}s that are notified whenever the |
| 64 | * trust state changes for any user. |
| 65 | * |
| 66 | * Trust state and the setting of enabled agents is kept per user and each user has its own |
| 67 | * instance of a {@link android.service.trust.TrustAgentService}. |
| 68 | */ |
| 69 | public class TrustManagerService extends SystemService { |
| 70 | |
| 71 | private static final boolean DEBUG = false; |
| 72 | private static final String TAG = "TrustManagerService"; |
| 73 | |
| 74 | private static final Intent TRUST_AGENT_INTENT = |
| 75 | new Intent(TrustAgentService.SERVICE_INTERFACE); |
| 76 | |
| 77 | private static final int MSG_REGISTER_LISTENER = 1; |
| 78 | private static final int MSG_UNREGISTER_LISTENER = 2; |
| 79 | private static final int MSG_DISPATCH_UNLOCK_ATTEMPT = 3; |
| 80 | private static final int MSG_ENABLED_AGENTS_CHANGED = 4; |
| 81 | |
| 82 | private final ArraySet<AgentInfo> mActiveAgents = new ArraySet<AgentInfo>(); |
| 83 | private final ArrayList<ITrustListener> mTrustListeners = new ArrayList<ITrustListener>(); |
| 84 | private final Context mContext; |
| 85 | |
| 86 | private UserManager mUserManager; |
| 87 | |
| 88 | /** |
| 89 | * Cache for {@link #refreshAgentList()} |
| 90 | */ |
| 91 | private final ArraySet<AgentInfo> mObsoleteAgents = new ArraySet<AgentInfo>(); |
| 92 | |
| 93 | |
| 94 | public TrustManagerService(Context context) { |
| 95 | super(context); |
| 96 | mContext = context; |
| 97 | mUserManager = (UserManager) mContext.getSystemService(Context.USER_SERVICE); |
| 98 | } |
| 99 | |
| 100 | @Override |
| 101 | public void onStart() { |
| 102 | publishBinderService(Context.TRUST_SERVICE, mService); |
| 103 | } |
| 104 | |
| 105 | @Override |
| 106 | public void onBootPhase(int phase) { |
| 107 | if (phase == SystemService.PHASE_SYSTEM_SERVICES_READY && !isSafeMode()) { |
| 108 | // Listen for package changes |
| 109 | mPackageMonitor.register(mContext, mHandler.getLooper(), UserHandle.ALL, true); |
| 110 | refreshAgentList(); |
| 111 | } |
| 112 | } |
| 113 | |
| 114 | // Agent management |
| 115 | |
| 116 | private static final class AgentInfo { |
| 117 | CharSequence label; |
| 118 | Drawable icon; |
| 119 | ComponentName component; // service that implements ITrustAgent |
| 120 | ComponentName settings; // setting to launch to modify agent. |
| 121 | TrustAgentWrapper agent; |
| 122 | int userId; |
| 123 | |
| 124 | @Override |
| 125 | public boolean equals(Object other) { |
| 126 | if (!(other instanceof AgentInfo)) { |
| 127 | return false; |
| 128 | } |
| 129 | AgentInfo o = (AgentInfo) other; |
| 130 | return component.equals(o.component) && userId == o.userId; |
| 131 | } |
| 132 | |
| 133 | @Override |
| 134 | public int hashCode() { |
| 135 | return component.hashCode() * 31 + userId; |
| 136 | } |
| 137 | } |
| 138 | |
| 139 | private void updateTrustAll() { |
| 140 | List<UserInfo> userInfos = mUserManager.getUsers(true /* excludeDying */); |
| 141 | for (UserInfo userInfo : userInfos) { |
| 142 | updateTrust(userInfo.id); |
| 143 | } |
| 144 | } |
| 145 | |
| 146 | public void updateTrust(int userId) { |
| 147 | dispatchOnTrustChanged(aggregateIsTrusted(userId), userId); |
| 148 | } |
| 149 | |
| 150 | protected void refreshAgentList() { |
| 151 | if (DEBUG) Slog.d(TAG, "refreshAgentList()"); |
| 152 | PackageManager pm = mContext.getPackageManager(); |
| 153 | |
| 154 | List<UserInfo> userInfos = mUserManager.getUsers(true /* excludeDying */); |
| 155 | LockPatternUtils lockPatternUtils = new LockPatternUtils(mContext); |
| 156 | |
| 157 | mObsoleteAgents.clear(); |
| 158 | mObsoleteAgents.addAll(mActiveAgents); |
| 159 | |
| 160 | for (UserInfo userInfo : userInfos) { |
| 161 | List<ComponentName> enabledAgents = lockPatternUtils.getEnabledTrustAgents(userInfo.id); |
| 162 | if (enabledAgents == null) { |
| 163 | continue; |
| 164 | } |
| 165 | List<ResolveInfo> resolveInfos = pm.queryIntentServicesAsUser(TRUST_AGENT_INTENT, |
| 166 | PackageManager.GET_META_DATA, userInfo.id); |
| 167 | for (ResolveInfo resolveInfo : resolveInfos) { |
| 168 | if (resolveInfo.serviceInfo == null) continue; |
| 169 | ComponentName name = getComponentName(resolveInfo); |
| 170 | if (!enabledAgents.contains(name)) continue; |
| 171 | |
| 172 | AgentInfo agentInfo = new AgentInfo(); |
| 173 | agentInfo.component = name; |
| 174 | agentInfo.userId = userInfo.id; |
| 175 | if (!mActiveAgents.contains(agentInfo)) { |
| 176 | agentInfo.label = resolveInfo.loadLabel(pm); |
| 177 | agentInfo.icon = resolveInfo.loadIcon(pm); |
| 178 | agentInfo.settings = getSettingsComponentName(pm, resolveInfo); |
| 179 | agentInfo.agent = new TrustAgentWrapper(mContext, this, |
| 180 | new Intent().setComponent(name), userInfo.getUserHandle()); |
| 181 | mActiveAgents.add(agentInfo); |
| 182 | } else { |
| 183 | mObsoleteAgents.remove(agentInfo); |
| 184 | } |
| 185 | } |
| 186 | } |
| 187 | |
| 188 | boolean trustMayHaveChanged = false; |
| 189 | for (int i = 0; i < mObsoleteAgents.size(); i++) { |
Adrian Roos | 81e0466 | 2014-04-30 17:48:18 +0200 | [diff] [blame] | 190 | AgentInfo info = mObsoleteAgents.valueAt(i); |
Adrian Roos | 82142c2 | 2014-03-27 14:56:59 +0100 | [diff] [blame] | 191 | if (info.agent.isTrusted()) { |
| 192 | trustMayHaveChanged = true; |
| 193 | } |
| 194 | info.agent.unbind(); |
Adrian Roos | a595642 | 2014-04-30 18:23:38 +0200 | [diff] [blame] | 195 | mActiveAgents.remove(info); |
Adrian Roos | 82142c2 | 2014-03-27 14:56:59 +0100 | [diff] [blame] | 196 | } |
| 197 | |
| 198 | if (trustMayHaveChanged) { |
| 199 | updateTrustAll(); |
| 200 | } |
| 201 | } |
| 202 | |
| 203 | private ComponentName getSettingsComponentName(PackageManager pm, ResolveInfo resolveInfo) { |
| 204 | if (resolveInfo == null || resolveInfo.serviceInfo == null |
| 205 | || resolveInfo.serviceInfo.metaData == null) return null; |
| 206 | String cn = null; |
| 207 | XmlResourceParser parser = null; |
| 208 | Exception caughtException = null; |
| 209 | try { |
| 210 | parser = resolveInfo.serviceInfo.loadXmlMetaData(pm, |
| 211 | TrustAgentService.TRUST_AGENT_META_DATA); |
| 212 | if (parser == null) { |
| 213 | Slog.w(TAG, "Can't find " + TrustAgentService.TRUST_AGENT_META_DATA + " meta-data"); |
| 214 | return null; |
| 215 | } |
| 216 | Resources res = pm.getResourcesForApplication(resolveInfo.serviceInfo.applicationInfo); |
| 217 | AttributeSet attrs = Xml.asAttributeSet(parser); |
| 218 | int type; |
| 219 | while ((type = parser.next()) != XmlPullParser.END_DOCUMENT |
| 220 | && type != XmlPullParser.START_TAG) { |
| 221 | // Drain preamble. |
| 222 | } |
| 223 | String nodeName = parser.getName(); |
Adrian Roos | 7e03dfc | 2014-05-16 16:06:28 +0200 | [diff] [blame^] | 224 | if (!"trust-agent".equals(nodeName)) { |
| 225 | Slog.w(TAG, "Meta-data does not start with trust-agent tag"); |
Adrian Roos | 82142c2 | 2014-03-27 14:56:59 +0100 | [diff] [blame] | 226 | return null; |
| 227 | } |
| 228 | TypedArray sa = res |
| 229 | .obtainAttributes(attrs, com.android.internal.R.styleable.TrustAgent); |
| 230 | cn = sa.getString(com.android.internal.R.styleable.TrustAgent_settingsActivity); |
| 231 | sa.recycle(); |
| 232 | } catch (PackageManager.NameNotFoundException e) { |
| 233 | caughtException = e; |
| 234 | } catch (IOException e) { |
| 235 | caughtException = e; |
| 236 | } catch (XmlPullParserException e) { |
| 237 | caughtException = e; |
| 238 | } finally { |
| 239 | if (parser != null) parser.close(); |
| 240 | } |
| 241 | if (caughtException != null) { |
| 242 | Slog.w(TAG, "Error parsing : " + resolveInfo.serviceInfo.packageName, caughtException); |
| 243 | return null; |
| 244 | } |
| 245 | if (cn == null) { |
| 246 | return null; |
| 247 | } |
| 248 | if (cn.indexOf('/') < 0) { |
| 249 | cn = resolveInfo.serviceInfo.packageName + "/" + cn; |
| 250 | } |
| 251 | return ComponentName.unflattenFromString(cn); |
| 252 | } |
| 253 | |
| 254 | private ComponentName getComponentName(ResolveInfo resolveInfo) { |
| 255 | if (resolveInfo == null || resolveInfo.serviceInfo == null) return null; |
| 256 | return new ComponentName(resolveInfo.serviceInfo.packageName, resolveInfo.serviceInfo.name); |
| 257 | } |
| 258 | |
| 259 | // Agent dispatch and aggregation |
| 260 | |
| 261 | private boolean aggregateIsTrusted(int userId) { |
| 262 | for (int i = 0; i < mActiveAgents.size(); i++) { |
| 263 | AgentInfo info = mActiveAgents.valueAt(i); |
| 264 | if (info.userId == userId) { |
| 265 | if (info.agent.isTrusted()) { |
| 266 | return true; |
| 267 | } |
| 268 | } |
| 269 | } |
| 270 | return false; |
| 271 | } |
| 272 | |
| 273 | private void dispatchUnlockAttempt(boolean successful, int userId) { |
| 274 | for (int i = 0; i < mActiveAgents.size(); i++) { |
| 275 | AgentInfo info = mActiveAgents.valueAt(i); |
| 276 | if (info.userId == userId) { |
| 277 | info.agent.onUnlockAttempt(successful); |
| 278 | } |
| 279 | } |
| 280 | } |
| 281 | |
| 282 | // Listeners |
| 283 | |
| 284 | private void addListener(ITrustListener listener) { |
| 285 | for (int i = 0; i < mTrustListeners.size(); i++) { |
| 286 | if (mTrustListeners.get(i).asBinder() == listener.asBinder()) { |
| 287 | return; |
| 288 | } |
| 289 | } |
| 290 | mTrustListeners.add(listener); |
| 291 | } |
| 292 | |
| 293 | private void removeListener(ITrustListener listener) { |
| 294 | for (int i = 0; i < mTrustListeners.size(); i++) { |
| 295 | if (mTrustListeners.get(i).asBinder() == listener.asBinder()) { |
| 296 | mTrustListeners.get(i); |
| 297 | return; |
| 298 | } |
| 299 | } |
| 300 | } |
| 301 | |
| 302 | private void dispatchOnTrustChanged(boolean enabled, int userId) { |
| 303 | for (int i = 0; i < mTrustListeners.size(); i++) { |
| 304 | try { |
| 305 | mTrustListeners.get(i).onTrustChanged(enabled, userId); |
| 306 | } catch (RemoteException e) { |
| 307 | Slog.e(TAG, "Exception while notifying TrustListener. Removing listener.", e); |
| 308 | mTrustListeners.get(i); |
| 309 | i--; |
| 310 | } |
| 311 | } |
| 312 | } |
| 313 | |
| 314 | // Plumbing |
| 315 | |
| 316 | private final IBinder mService = new ITrustManager.Stub() { |
| 317 | @Override |
| 318 | public void reportUnlockAttempt(boolean authenticated, int userId) throws RemoteException { |
| 319 | enforceReportPermission(); |
| 320 | mHandler.obtainMessage(MSG_DISPATCH_UNLOCK_ATTEMPT, authenticated ? 1 : 0, userId) |
| 321 | .sendToTarget(); |
| 322 | } |
| 323 | |
| 324 | @Override |
| 325 | public void reportEnabledTrustAgentsChanged(int userId) throws RemoteException { |
| 326 | enforceReportPermission(); |
| 327 | // coalesce refresh messages. |
| 328 | mHandler.removeMessages(MSG_ENABLED_AGENTS_CHANGED); |
| 329 | mHandler.sendEmptyMessage(MSG_ENABLED_AGENTS_CHANGED); |
| 330 | } |
| 331 | |
| 332 | @Override |
| 333 | public void registerTrustListener(ITrustListener trustListener) throws RemoteException { |
| 334 | enforceListenerPermission(); |
| 335 | mHandler.obtainMessage(MSG_REGISTER_LISTENER, trustListener).sendToTarget(); |
| 336 | } |
| 337 | |
| 338 | @Override |
| 339 | public void unregisterTrustListener(ITrustListener trustListener) throws RemoteException { |
| 340 | enforceListenerPermission(); |
| 341 | mHandler.obtainMessage(MSG_UNREGISTER_LISTENER, trustListener).sendToTarget(); |
| 342 | } |
| 343 | |
| 344 | private void enforceReportPermission() { |
| 345 | mContext.enforceCallingPermission(Manifest.permission.ACCESS_KEYGUARD_SECURE_STORAGE, |
| 346 | "reporting trust events"); |
| 347 | } |
| 348 | |
| 349 | private void enforceListenerPermission() { |
| 350 | mContext.enforceCallingPermission(Manifest.permission.TRUST_LISTENER, |
| 351 | "register trust listener"); |
| 352 | } |
| 353 | }; |
| 354 | |
| 355 | private final Handler mHandler = new Handler() { |
| 356 | @Override |
| 357 | public void handleMessage(Message msg) { |
| 358 | switch (msg.what) { |
| 359 | case MSG_REGISTER_LISTENER: |
| 360 | addListener((ITrustListener) msg.obj); |
| 361 | break; |
| 362 | case MSG_UNREGISTER_LISTENER: |
| 363 | removeListener((ITrustListener) msg.obj); |
| 364 | break; |
| 365 | case MSG_DISPATCH_UNLOCK_ATTEMPT: |
| 366 | dispatchUnlockAttempt(msg.arg1 != 0, msg.arg2); |
| 367 | break; |
| 368 | case MSG_ENABLED_AGENTS_CHANGED: |
| 369 | refreshAgentList(); |
| 370 | break; |
| 371 | } |
| 372 | } |
| 373 | }; |
| 374 | |
| 375 | private final PackageMonitor mPackageMonitor = new PackageMonitor() { |
| 376 | @Override |
| 377 | public void onSomePackagesChanged() { |
| 378 | refreshAgentList(); |
| 379 | } |
| 380 | |
| 381 | @Override |
| 382 | public boolean onPackageChanged(String packageName, int uid, String[] components) { |
| 383 | // We're interested in all changes, even if just some components get enabled / disabled. |
| 384 | return true; |
| 385 | } |
| 386 | }; |
| 387 | } |