Update TrustAgentService API after review

This change incorporates API council feedback and enables the
TrustAgent whitelisting API.

It also contains a minor cleanup of DPM's use of UserHandle
to eliminate unnecessary object creation.

Fixes bug 17008504

Change-Id: I63cc50169fde54b34406845818bcaf6aadc1a3db

3 files changed, 61 insertions, 37 deletions

diff --git a/core/java/android/service/trust/ITrustAgentService.aidl b/core/java/android/service/trust/ITrustAgentService.aidl
index bd80a3f..bb0c2b2 100644
--- a/core/java/android/service/trust/ITrustAgentService.aidl
+++ b/core/java/android/service/trust/ITrustAgentService.aidl
@@ -15,7 +15,7 @@
  */
 package android.service.trust;
 
-import android.os.Bundle;
+import android.os.PersistableBundle;
 import android.service.trust.ITrustAgentServiceCallback;
 
 /**
@@ -25,6 +25,6 @@ import android.service.trust.ITrustAgentServiceCallback;
 interface ITrustAgentService {
     oneway void onUnlockAttempt(boolean successful);
     oneway void onTrustTimeout();
+    oneway void onConfigure(in List<PersistableBundle> options, IBinder token);
     oneway void setCallback(ITrustAgentServiceCallback callback);
-    oneway void setTrustAgentFeaturesEnabled(in Bundle options, IBinder token);
 }
diff --git a/core/java/android/service/trust/ITrustAgentServiceCallback.aidl b/core/java/android/service/trust/ITrustAgentServiceCallback.aidl
index b107bcc..76b2be0 100644
--- a/core/java/android/service/trust/ITrustAgentServiceCallback.aidl
+++ b/core/java/android/service/trust/ITrustAgentServiceCallback.aidl
@@ -27,5 +27,5 @@ oneway interface ITrustAgentServiceCallback {
     void grantTrust(CharSequence message, long durationMs, boolean initiatedByUser);
     void revokeTrust();
     void setManagingTrust(boolean managingTrust);
-    void onSetTrustAgentFeaturesEnabledCompleted(boolean result, IBinder token);
+    void onConfigureCompleted(boolean result, IBinder token);
 }
diff --git a/core/java/android/service/trust/TrustAgentService.java b/core/java/android/service/trust/TrustAgentService.java
index 3ef5b37..00d60c0 100644
--- a/core/java/android/service/trust/TrustAgentService.java
+++ b/core/java/android/service/trust/TrustAgentService.java
@@ -29,11 +29,14 @@ import android.os.Bundle;
 import android.os.Handler;
 import android.os.IBinder;
 import android.os.Message;
+import android.os.PersistableBundle;
 import android.os.RemoteException;
 import android.os.SystemClock;
 import android.util.Log;
 import android.util.Slog;
 
+import java.util.List;
+
 /**
  * A service that notifies the system about whether it believes the environment of the device
  * to be trusted.
@@ -86,16 +89,46 @@ public class TrustAgentService extends Service {
      */
     public static final String TRUST_AGENT_META_DATA = "android.service.trust.trustagent";
 
+    private static final int MSG_UNLOCK_ATTEMPT = 1;
+    private static final int MSG_CONFIGURE = 2;
+    private static final int MSG_TRUST_TIMEOUT = 3;
+
     /**
-     * A white list of features that the given trust agent should support when otherwise disabled
-     * by device policy.
-     * @hide
+     * Container class for a list of configuration options and helper methods
      */
-    public static final String KEY_FEATURES = "trust_agent_features";
+    public static final class Configuration {
+        public final List<PersistableBundle> options;
+        public Configuration(List<PersistableBundle> opts) {
+            options = opts;
+        }
 
-    private static final int MSG_UNLOCK_ATTEMPT = 1;
-    private static final int MSG_SET_TRUST_AGENT_FEATURES_ENABLED = 2;
-    private static final int MSG_TRUST_TIMEOUT = 3;
+        /**
+         * Very basic method to determine if all bundles have the given feature, regardless
+         * of type.
+         * @param option String to search for.
+         * @return true if found in all bundles.
+         */
+        public boolean hasOption(String option) {
+            if (options == null || options.size() == 0) return false;
+            final int N = options.size();
+            for (int i = 0; i < N; i++) {
+                if (!options.get(i).containsKey(option)) return false;
+            }
+            return true;
+        }
+    }
+
+    /**
+     * Class containing raw data for a given configuration request.
+     */
+    private static final class ConfigurationData {
+        final IBinder token;
+        final List<PersistableBundle> options;
+        ConfigurationData(List<PersistableBundle> opts, IBinder t) {
+            options = opts;
+            token = t;
+        }
+    }
 
     private ITrustAgentServiceCallback mCallback;
 
@@ -112,13 +145,12 @@ public class TrustAgentService extends Service {
                 case MSG_UNLOCK_ATTEMPT:
                     onUnlockAttempt(msg.arg1 != 0);
                     break;
-                case MSG_SET_TRUST_AGENT_FEATURES_ENABLED:
-                    Bundle features = msg.peekData();
-                    IBinder token = (IBinder) msg.obj;
-                    boolean result = onSetTrustAgentFeaturesEnabled(features);
+                case MSG_CONFIGURE:
+                    ConfigurationData data = (ConfigurationData) msg.obj;
+                    boolean result = onConfigure(new Configuration(data.options));
                     try {
                         synchronized (mLock) {
-                            mCallback.onSetTrustAgentFeaturesEnabledCompleted(result, token);
+                            mCallback.onConfigureCompleted(result, data.token);
                         }
                     } catch (RemoteException e) {
                         onError("calling onSetTrustAgentFeaturesEnabledCompleted()");
@@ -171,23 +203,16 @@ public class TrustAgentService extends Service {
     }
 
     /**
-     * Called when device policy wants to restrict features in the agent in response to
-     * {@link DevicePolicyManager#setTrustAgentFeaturesEnabled(ComponentName, ComponentName, java.util.List) }.
-     * Agents that support this feature should overload this method and return 'true'.
+     * Called when device policy admin wants to enable specific options for agent in response to
+     * {@link DevicePolicyManager#setKeyguardDisabledFeatures(ComponentName, int)} and
+     * {@link DevicePolicyManager#setTrustAgentConfiguration(ComponentName, ComponentName,
+     * PersistableBundle)}.
+     * <p>Agents that support configuration options should overload this method and return 'true'.
      *
-     * The list of options can be obtained by calling
-     * options.getStringArrayList({@link #KEY_FEATURES}). Presence of a feature string in the list
-     * means it should be enabled ("white-listed"). Absence of the feature means it should be
-     * disabled. An empty list means all features should be disabled.
-     *
-     * This function is only called if {@link DevicePolicyManager#KEYGUARD_DISABLE_TRUST_AGENTS} is
-     * set.
-     *
-     * @param options Option feature bundle.
-     * @return true if the {@link TrustAgentService} supports this feature.
-     * @hide
+     * @param options bundle containing all options or null if none.
+     * @return true if the {@link TrustAgentService} supports configuration options.
      */
-    public boolean onSetTrustAgentFeaturesEnabled(Bundle options) {
+    public boolean onConfigure(Configuration options) {
         return false;
     }
 
@@ -295,6 +320,12 @@ public class TrustAgentService extends Service {
         }
 
         @Override /* Binder API */
+        public void onConfigure(List<PersistableBundle> args, IBinder token) {
+            mHandler.obtainMessage(MSG_CONFIGURE, new ConfigurationData(args, token))
+                    .sendToTarget();
+        }
+
+        @Override /* Binder API */
         public void setCallback(ITrustAgentServiceCallback callback) {
             synchronized (mLock) {
                 mCallback = callback;
@@ -313,13 +344,6 @@ public class TrustAgentService extends Service {
                 }
             }
         }
-
-        @Override /* Binder API */
-        public void setTrustAgentFeaturesEnabled(Bundle features, IBinder token) {
-            Message msg = mHandler.obtainMessage(MSG_SET_TRUST_AGENT_FEATURES_ENABLED, token);
-            msg.setData(features);
-            msg.sendToTarget();
-        }
     }
 
 }