content: /*
   * Copyright (C) 2016 The Android Open Source Project
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  
  package com.android.server.security;
  
  import android.content.Context;
  import android.content.pm.PackageInfo;
  import android.content.pm.PackageManager;
  import android.content.pm.PackageManager.NameNotFoundException;
  import android.os.Binder;
  import android.os.RemoteException;
  import android.os.UserHandle;
  import android.security.keymaster.KeyAttestationPackageInfo;
  import android.security.keymaster.KeyAttestationApplicationId;
  import android.security.keymaster.IKeyAttestationApplicationIdProvider;
  
  /**
   * @hide
   * The KeyAttestationApplicationIdProviderService provides information describing the possible
   * applications identified by a UID. Due to UID sharing, this KeyAttestationApplicationId can
   * comprise information about multiple packages. The Information is used by keystore to describe
   * the initiating application of a key attestation procedure.
   */
  public class KeyAttestationApplicationIdProviderService
          extends IKeyAttestationApplicationIdProvider.Stub {
  
      public KeyAttestationApplicationIdProviderService(Context context) {
          mPackageManager = context.getPackageManager();
      }
  
      private PackageManager mPackageManager;
  
      public KeyAttestationApplicationId getKeyAttestationApplicationId(int uid)
              throws RemoteException {
          if (Binder.getCallingUid() != android.os.Process.KEYSTORE_UID) {
              throw new SecurityException("This service can only be used by Keystore");
          }
          KeyAttestationPackageInfo[] keyAttestationPackageInfos = null;
          final long token = Binder.clearCallingIdentity();
          try {
              String[] packageNames = mPackageManager.getPackagesForUid(uid);
              if (packageNames == null) {
                  throw new RemoteException("No packages for uid");
              }
              int userId = UserHandle.getUserId(uid);
              keyAttestationPackageInfos = new KeyAttestationPackageInfo[packageNames.length];
  
              for (int i = 0; i < packageNames.length; ++i) {
                  PackageInfo packageInfo = mPackageManager.getPackageInfoAsUser(packageNames[i],
                          PackageManager.GET_SIGNATURES, userId);
                  keyAttestationPackageInfos[i] = new KeyAttestationPackageInfo(packageNames[i],
                          packageInfo.getLongVersionCode(), packageInfo.signatures);
              }
          } catch (NameNotFoundException nnfe) {
              throw new RemoteException(nnfe.getMessage());
          } finally {
              Binder.restoreCallingIdentity(token);
          }
          return new KeyAttestationApplicationId(keyAttestationPackageInfos);
      }
  }
  