IMplement CryptoInputParcelCacheService

OpenKeychain/src/main/AndroidManifest.xml

@@ -696,6 +696,10 @@
             android:name=".service.PassphraseCacheService"
             android:exported="false"
             android:process=":passphrase_cache" />
+        <service
+            android:name=".remote.CryptoInputParcelCacheService"
+            android:exported="false"
+            android:process=":remote_api" />
         <service
             android:name=".service.KeychainIntentService"
             android:exported="false" />

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/remote/CryptoInputParcelCacheService.java

@@ -0,0 +1,246 @@
+/*
+ * Copyright (C) 2015 Dominik Schürmann <dominik@dominikschuermann.de>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.sufficientlysecure.keychain.remote;
+
+import android.app.Service;
+import android.content.Context;
+import android.content.Intent;
+import android.os.Binder;
+import android.os.Bundle;
+import android.os.Handler;
+import android.os.HandlerThread;
+import android.os.IBinder;
+import android.os.Message;
+import android.os.Messenger;
+import android.os.RemoteException;
+
+import org.openintents.openpgp.util.OpenPgpApi;
+import org.sufficientlysecure.keychain.Constants;
+import org.sufficientlysecure.keychain.service.input.CryptoInputParcel;
+import org.sufficientlysecure.keychain.util.Log;
+
+import java.util.UUID;
+import java.util.concurrent.ConcurrentHashMap;
+
+
+public class CryptoInputParcelCacheService extends Service {
+
+    public static final String ACTION_ADD = Constants.INTENT_PREFIX + "ADD";
+    public static final String ACTION_GET = Constants.INTENT_PREFIX + "GET";
+
+    public static final String EXTRA_CRYPTO_INPUT_PARCEL = "crypto_input_parcel";
+    public static final String EXTRA_UUID1 = "uuid1";
+    public static final String EXTRA_UUID2 = "uuid2";
+    public static final String EXTRA_MESSENGER = "messenger";
+
+    private static final int MSG_GET_OKAY = 1;
+    private static final int MSG_GET_NOT_FOUND = 2;
+
+    Context mContext;
+
+    private static final UUID NULL_UUID = new UUID(0, 0);
+
+    private ConcurrentHashMap<UUID, CryptoInputParcel> mCache = new ConcurrentHashMap<>();
+
+    public static class InputParcelNotFound extends Exception {
+        public InputParcelNotFound() {
+        }
+
+        public InputParcelNotFound(String name) {
+            super(name);
+        }
+    }
+
+    public static void addCryptoInputParcel(Context context, Intent data, CryptoInputParcel inputParcel) {
+        UUID mTicket = addCryptoInputParcel(context, inputParcel);
+        // And write out the UUID most and least significant bits.
+        data.putExtra(OpenPgpApi.EXTRA_CALL_UUID1, mTicket.getMostSignificantBits());
+        data.putExtra(OpenPgpApi.EXTRA_CALL_UUID2, mTicket.getLeastSignificantBits());
+    }
+
+    public static CryptoInputParcel getCryptoInputParcel(Context context, Intent data) {
+        if (!data.getExtras().containsKey(OpenPgpApi.EXTRA_CALL_UUID1)
+                || !data.getExtras().containsKey(OpenPgpApi.EXTRA_CALL_UUID2)) {
+            return null;
+        }
+        long mostSig = data.getLongExtra(OpenPgpApi.EXTRA_CALL_UUID1, 0);
+        long leastSig = data.getLongExtra(OpenPgpApi.EXTRA_CALL_UUID2, 0);
+        UUID uuid = new UUID(mostSig, leastSig);
+        try {
+            return getCryptoInputParcel(context, uuid);
+        } catch (InputParcelNotFound inputParcelNotFound) {
+            return null;
+        }
+    }
+
+    private static UUID addCryptoInputParcel(Context context, CryptoInputParcel inputParcel) {
+        UUID uuid = UUID.randomUUID();
+
+        Intent intent = new Intent(context, CryptoInputParcelCacheService.class);
+        intent.setAction(ACTION_ADD);
+        intent.putExtra(EXTRA_CRYPTO_INPUT_PARCEL, inputParcel);
+        intent.putExtra(EXTRA_UUID1, uuid.getMostSignificantBits());
+        intent.putExtra(EXTRA_UUID2, uuid.getLeastSignificantBits());
+        context.startService(intent);
+        return uuid;
+    }
+
+    private static CryptoInputParcel getCryptoInputParcel(Context context, UUID uuid) throws InputParcelNotFound {
+        Intent intent = new Intent(context, CryptoInputParcelCacheService.class);
+        intent.setAction(ACTION_GET);
+
+        final Object mutex = new Object();
+        final Message returnMessage = Message.obtain();
+
+        HandlerThread handlerThread = new HandlerThread("getParcelableThread");
+        handlerThread.start();
+        Handler returnHandler = new Handler(handlerThread.getLooper()) {
+            @Override
+            public void handleMessage(Message message) {
+                // copy over result to handle after mutex.wait
+                returnMessage.what = message.what;
+                returnMessage.copyFrom(message);
+                synchronized (mutex) {
+                    mutex.notify();
+                }
+                // quit handlerThread
+                getLooper().quit();
+            }
+        };
+
+        // Create a new Messenger for the communication back
+        Messenger messenger = new Messenger(returnHandler);
+        intent.putExtra(EXTRA_UUID1, uuid.getMostSignificantBits());
+        intent.putExtra(EXTRA_UUID2, uuid.getLeastSignificantBits());
+        intent.putExtra(EXTRA_MESSENGER, messenger);
+        // send intent to this service
+        context.startService(intent);
+
+        // Wait on mutex until parcelable is returned to handlerThread. Note that this local
+        // variable is used in the handler closure above, so it does make sense here!
+        // noinspection SynchronizationOnLocalVariableOrMethodParameter
+        synchronized (mutex) {
+            try {
+                mutex.wait(3000);
+            } catch (InterruptedException e) {
+                // don't care
+            }
+        }
+
+        switch (returnMessage.what) {
+            case MSG_GET_OKAY:
+                Bundle returnData = returnMessage.getData();
+                returnData.setClassLoader(context.getClassLoader());
+                return returnData.getParcelable(EXTRA_CRYPTO_INPUT_PARCEL);
+            case MSG_GET_NOT_FOUND:
+                throw new InputParcelNotFound();
+            default:
+                Log.e(Constants.TAG, "timeout!");
+                throw new InputParcelNotFound("should not happen!");
+        }
+    }
+
+    /**
+     * Executed when service is started by intent
+     */
+    @Override
+    public int onStartCommand(Intent intent, int flags, int startId) {
+
+        if (intent == null || intent.getAction() == null) {
+            return START_NOT_STICKY;
+        }
+
+        String action = intent.getAction();
+        switch (action) {
+            case ACTION_ADD: {
+                long uuid1 = intent.getLongExtra(EXTRA_UUID1, 0);
+                long uuid2 = intent.getLongExtra(EXTRA_UUID2, 0);
+                UUID uuid = new UUID(uuid1, uuid2);
+                CryptoInputParcel inputParcel = intent.getParcelableExtra(EXTRA_CRYPTO_INPUT_PARCEL);
+                mCache.put(uuid, inputParcel);
+
+                break;
+            }
+            case ACTION_GET: {
+                long uuid1 = intent.getLongExtra(EXTRA_UUID1, 0);
+                long uuid2 = intent.getLongExtra(EXTRA_UUID2, 0);
+                UUID uuid = new UUID(uuid1, uuid2);
+                Messenger messenger = intent.getParcelableExtra(EXTRA_MESSENGER);
+
+                Message msg = Message.obtain();
+                // UUID.equals isn't well documented; we use compareTo instead.
+                if (NULL_UUID.compareTo(uuid) == 0) {
+                    msg.what = MSG_GET_NOT_FOUND;
+                } else {
+                    CryptoInputParcel inputParcel = mCache.get(uuid);
+                    mCache.remove(uuid);
+                    msg.what = MSG_GET_OKAY;
+                    Bundle bundle = new Bundle();
+                    bundle.putParcelable(EXTRA_CRYPTO_INPUT_PARCEL, inputParcel);
+                    msg.setData(bundle);
+                }
+
+                try {
+                    messenger.send(msg);
+                } catch (RemoteException e) {
+                    Log.e(Constants.TAG, "CryptoInputParcelCacheService: Sending message failed", e);
+                }
+                break;
+            }
+            default: {
+                Log.e(Constants.TAG, "CryptoInputParcelCacheService: Intent or Intent Action not supported!");
+                break;
+            }
+        }
+
+        if (mCache.size() <= 0) {
+            // stop whole service if cache is empty
+            Log.d(Constants.TAG, "CryptoInputParcelCacheService: No passphrases remaining in memory, stopping service!");
+            stopSelf();
+        }
+
+        return START_NOT_STICKY;
+    }
+
+    @Override
+    public void onCreate() {
+        super.onCreate();
+        mContext = this;
+        Log.d(Constants.TAG, "CryptoInputParcelCacheService, onCreate()");
+    }
+
+    @Override
+    public void onDestroy() {
+        super.onDestroy();
+        Log.d(Constants.TAG, "CryptoInputParcelCacheService, onDestroy()");
+    }
+
+    @Override
+    public IBinder onBind(Intent intent) {
+        return mBinder;
+    }
+
+    public class CryptoInputParcelCacheServiceBinder extends Binder {
+        public CryptoInputParcelCacheService getService() {
+            return CryptoInputParcelCacheService.this;
+        }
+    }
+
+    private final IBinder mBinder = new CryptoInputParcelCacheServiceBinder();
+
+}

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/remote/OpenPgpService.java

@@ -36,7 +36,6 @@ import org.sufficientlysecure.keychain.Constants;
 import org.sufficientlysecure.keychain.operations.results.DecryptVerifyResult;
 import org.sufficientlysecure.keychain.operations.results.OperationResult.LogEntryParcel;
 import org.sufficientlysecure.keychain.operations.results.PgpSignEncryptResult;
-import org.sufficientlysecure.keychain.operations.results.SignEncryptResult;
 import org.sufficientlysecure.keychain.pgp.PgpConstants;
 import org.sufficientlysecure.keychain.pgp.PgpDecryptVerify;
 import org.sufficientlysecure.keychain.pgp.PgpSignEncryptInputParcel;
@@ -57,7 +56,6 @@ import org.sufficientlysecure.keychain.ui.PassphraseDialogActivity;
 import org.sufficientlysecure.keychain.ui.ViewKeyActivity;
 import org.sufficientlysecure.keychain.util.InputData;
 import org.sufficientlysecure.keychain.util.Log;
-import org.sufficientlysecure.keychain.util.ParcelableCache;
 import org.sufficientlysecure.keychain.util.Passphrase;
 
 import java.io.IOException;
@@ -68,25 +66,6 @@ import java.util.Set;
 
 public class OpenPgpService extends RemoteService {
 
-    /**
-     * Instead of parceling the CryptoInputParcel, they are cached on our side to prevent
-     * leakage of passphrases, symmetric keys, an yubikey related pass-through values
-     */
-    private static ParcelableCache<CryptoInputParcel> inputParcelCache;
-    static {
-        inputParcelCache = new ParcelableCache<>();
-    }
-
-    public static void cacheCryptoInputParcel(Intent data, CryptoInputParcel inputParcel) {
-        inputParcelCache.cacheAndWriteToIntent(inputParcel, data,
-                OpenPgpApi.EXTRA_CALL_UUID1, OpenPgpApi.EXTRA_CALL_UUID2);
-    }
-
-    public static CryptoInputParcel getCryptoInputParcel(Intent data) {
-        return inputParcelCache.readFromIntentAndGetFromCache(data,
-                OpenPgpApi.EXTRA_CALL_UUID1, OpenPgpApi.EXTRA_CALL_UUID2);
-    }
-
     static final String[] EMAIL_SEARCH_PROJECTION = new String[]{
             KeyRings._ID,
             KeyRings.MASTER_KEY_ID,
@@ -283,7 +262,7 @@ public class OpenPgpService extends RemoteService {
             long inputLength = is.available();
             InputData inputData = new InputData(is, inputLength);
 
-            CryptoInputParcel inputParcel = getCryptoInputParcel(data);
+            CryptoInputParcel inputParcel = CryptoInputParcelCacheService.getCryptoInputParcel(this, data);
             if (inputParcel == null) {
                 inputParcel = new CryptoInputParcel();
             }
@@ -424,7 +403,7 @@ public class OpenPgpService extends RemoteService {
                         .setAdditionalEncryptId(signKeyId); // add sign key for encryption
             }
 
-            CryptoInputParcel inputParcel = getCryptoInputParcel(data);
+            CryptoInputParcel inputParcel = CryptoInputParcelCacheService.getCryptoInputParcel(this, data);
             if (inputParcel == null) {
                 inputParcel = new CryptoInputParcel();
             }
@@ -513,7 +492,7 @@ public class OpenPgpService extends RemoteService {
                     this, new ProviderHelper(getContext()), null, inputData, os
             );
 
-            CryptoInputParcel inputParcel = getCryptoInputParcel(data);
+            CryptoInputParcel inputParcel = CryptoInputParcelCacheService.getCryptoInputParcel(this, data);
             if (inputParcel == null) {
                 inputParcel = new CryptoInputParcel();
             }
@@ -768,9 +747,7 @@ public class OpenPgpService extends RemoteService {
         return null;
     }
 
-    // TODO: multi-threading
     private final IOpenPgpService.Stub mBinder = new IOpenPgpService.Stub() {
-
         @Override
         public Intent execute(Intent data, ParcelFileDescriptor input, ParcelFileDescriptor output) {
             try {
@@ -780,31 +757,43 @@ public class OpenPgpService extends RemoteService {
                 }
 
                 String action = data.getAction();
-                if (OpenPgpApi.ACTION_CLEARTEXT_SIGN.equals(action)) {
+                switch (action) {
+                    case OpenPgpApi.ACTION_CLEARTEXT_SIGN: {
                         return signImpl(data, input, output, true);
-                } else if (OpenPgpApi.ACTION_SIGN.equals(action)) {
+                    }
+                    case OpenPgpApi.ACTION_SIGN: {
                         // DEPRECATED: same as ACTION_CLEARTEXT_SIGN
                         Log.w(Constants.TAG, "You are using a deprecated API call, please use ACTION_CLEARTEXT_SIGN instead of ACTION_SIGN!");
                         return signImpl(data, input, output, true);
-                } else if (OpenPgpApi.ACTION_DETACHED_SIGN.equals(action)) {
+                    }
+                    case OpenPgpApi.ACTION_DETACHED_SIGN: {
                         return signImpl(data, input, output, false);
-                } else if (OpenPgpApi.ACTION_ENCRYPT.equals(action)) {
+                    }
+                    case OpenPgpApi.ACTION_ENCRYPT: {
                         return encryptAndSignImpl(data, input, output, false);
-                } else if (OpenPgpApi.ACTION_SIGN_AND_ENCRYPT.equals(action)) {
+                    }
+                    case OpenPgpApi.ACTION_SIGN_AND_ENCRYPT: {
                         return encryptAndSignImpl(data, input, output, true);
-                } else if (OpenPgpApi.ACTION_DECRYPT_VERIFY.equals(action)) {
+                    }
+                    case OpenPgpApi.ACTION_DECRYPT_VERIFY: {
                         return decryptAndVerifyImpl(data, input, output, false);
-                } else if (OpenPgpApi.ACTION_DECRYPT_METADATA.equals(action)) {
+                    }
+                    case OpenPgpApi.ACTION_DECRYPT_METADATA: {
                         return decryptAndVerifyImpl(data, input, output, true);
-                } else if (OpenPgpApi.ACTION_GET_SIGN_KEY_ID.equals(action)) {
+                    }
+                    case OpenPgpApi.ACTION_GET_SIGN_KEY_ID: {
                         return getSignKeyIdImpl(data);
-                } else if (OpenPgpApi.ACTION_GET_KEY_IDS.equals(action)) {
+                    }
+                    case OpenPgpApi.ACTION_GET_KEY_IDS: {
                         return getKeyIdsImpl(data);
-                } else if (OpenPgpApi.ACTION_GET_KEY.equals(action)) {
+                    }
+                    case OpenPgpApi.ACTION_GET_KEY: {
                         return getKeyImpl(data);
-                } else {
+                    }
+                    default: {
                         return null;
                     }
+                }
             } finally {
                 // always close input and output file descriptors even in error cases
                 if (input != null) {

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/service/PassphraseCacheService.java

@@ -337,11 +337,17 @@ public class PassphraseCacheService extends Service {
     public int onStartCommand(Intent intent, int flags, int startId) {
         Log.d(Constants.TAG, "PassphraseCacheService.onStartCommand()");
 
+        if (intent == null || intent.getAction() == null) {
+            updateService();
+            return START_STICKY;
+        }
+
         // register broadcastreceiver
         registerReceiver();
 
-        if (intent != null && intent.getAction() != null) {
+        String action = intent.getAction();
-            if (ACTION_PASSPHRASE_CACHE_ADD.equals(intent.getAction())) {
+        switch (action) {
+            case ACTION_PASSPHRASE_CACHE_ADD: {
                 long ttl = intent.getLongExtra(EXTRA_TTL, DEFAULT_TTL);
                 long masterKeyId = intent.getLongExtra(EXTRA_KEY_ID, -1);
                 long subKeyId = intent.getLongExtra(EXTRA_SUBKEY_ID, -1);
@@ -365,9 +371,9 @@ public class PassphraseCacheService extends Service {
                     AlarmManager am = (AlarmManager) this.getSystemService(Context.ALARM_SERVICE);
                     am.set(AlarmManager.RTC_WAKEUP, triggerTime, buildIntent(this, referenceKeyId));
                 }
-
+                break;
-                updateService();
+            }
-            } else if (ACTION_PASSPHRASE_CACHE_GET.equals(intent.getAction())) {
+            case ACTION_PASSPHRASE_CACHE_GET: {
                 long masterKeyId = intent.getLongExtra(EXTRA_KEY_ID, Constants.key.symmetric);
                 long subKeyId = intent.getLongExtra(EXTRA_SUBKEY_ID, Constants.key.symmetric);
                 Messenger messenger = intent.getParcelableExtra(EXTRA_MESSENGER);
@@ -395,7 +401,9 @@ public class PassphraseCacheService extends Service {
                 } catch (RemoteException e) {
                     Log.e(Constants.TAG, "PassphraseCacheService: Sending message failed", e);
                 }
-            } else if (ACTION_PASSPHRASE_CACHE_CLEAR.equals(intent.getAction())) {
+                break;
+            }
+            case ACTION_PASSPHRASE_CACHE_CLEAR: {
                 AlarmManager am = (AlarmManager) this.getSystemService(Context.ALARM_SERVICE);
 
                 if (intent.hasExtra(EXTRA_SUBKEY_ID) && intent.hasExtra(EXTRA_KEY_ID)) {
@@ -419,12 +427,15 @@ public class PassphraseCacheService extends Service {
                     mPassphraseCache.clear();
 
                 }
+                break;
+            }
+            default: {
+                Log.e(Constants.TAG, "PassphraseCacheService: Intent or Intent Action not supported!");
+                break;
+            }
+        }
 
         updateService();
-            } else {
-                Log.e(Constants.TAG, "PassphraseCacheService: Intent or Intent Action not supported!");
-            }
-        }
 
         return START_STICKY;
     }

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/NfcOperationActivity.java

@@ -10,13 +10,11 @@ import android.annotation.TargetApi;
 import android.content.Intent;
 import android.os.Build;
 import android.os.Bundle;
-import android.os.Parcelable;
 import android.view.WindowManager;
 
-import org.openintents.openpgp.util.OpenPgpApi;
 import org.sufficientlysecure.keychain.Constants;
 import org.sufficientlysecure.keychain.R;
-import org.sufficientlysecure.keychain.remote.OpenPgpService;
+import org.sufficientlysecure.keychain.remote.CryptoInputParcelCacheService;
 import org.sufficientlysecure.keychain.service.PassphraseCacheService;
 import org.sufficientlysecure.keychain.service.input.CryptoInputParcel;
 import org.sufficientlysecure.keychain.service.input.RequiredInputParcel;
@@ -93,7 +91,7 @@ public class NfcOperationActivity extends BaseNfcActivity {
         }
 
         if (mServiceIntent != null) {
-            OpenPgpService.cacheCryptoInputParcel(mServiceIntent, inputParcel);
+            CryptoInputParcelCacheService.addCryptoInputParcel(this, mServiceIntent, inputParcel);
             setResult(RESULT_OK, mServiceIntent);
         } else {
             Intent result = new Intent();

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/PassphraseDialogActivity.java

@@ -41,7 +41,6 @@ import android.widget.EditText;
 import android.widget.TextView;
 import android.widget.Toast;
 
-import org.openintents.openpgp.util.OpenPgpApi;
 import org.sufficientlysecure.keychain.Constants;
 import org.sufficientlysecure.keychain.R;
 import org.sufficientlysecure.keychain.compatibility.DialogFragmentWorkaround;
@@ -53,11 +52,10 @@ import org.sufficientlysecure.keychain.pgp.exception.PgpKeyNotFoundException;
 import org.sufficientlysecure.keychain.provider.CachedPublicKeyRing;
 import org.sufficientlysecure.keychain.provider.KeychainContract;
 import org.sufficientlysecure.keychain.provider.ProviderHelper;
-import org.sufficientlysecure.keychain.remote.OpenPgpService;
+import org.sufficientlysecure.keychain.remote.CryptoInputParcelCacheService;
 import org.sufficientlysecure.keychain.service.PassphraseCacheService;
 import org.sufficientlysecure.keychain.service.input.CryptoInputParcel;
 import org.sufficientlysecure.keychain.service.input.RequiredInputParcel;
-import org.sufficientlysecure.keychain.service.input.RequiredInputParcel.RequiredInputType;
 import org.sufficientlysecure.keychain.ui.dialog.CustomAlertDialogBuilder;
 import org.sufficientlysecure.keychain.util.Log;
 import org.sufficientlysecure.keychain.util.Passphrase;
@@ -428,7 +426,7 @@ public class PassphraseDialogActivity extends FragmentActivity {
 
             CryptoInputParcel inputParcel = new CryptoInputParcel(null, passphrase);
             if (mServiceIntent != null) {
-                OpenPgpService.cacheCryptoInputParcel(mServiceIntent, inputParcel);
+                CryptoInputParcelCacheService.addCryptoInputParcel(getActivity(), mServiceIntent, inputParcel);
                 getActivity().setResult(RESULT_OK, mServiceIntent);
             } else {
                 // also return passphrase back to activity

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/util/ParcelableCache.java

@@ -17,8 +17,6 @@
 
 package org.sufficientlysecure.keychain.util;
 
-import android.content.Intent;
-import android.os.Bundle;
 import android.os.Parcel;
 
 import java.util.UUID;
@@ -30,7 +28,7 @@ import java.util.concurrent.ConcurrentHashMap;
  * To overcome this issue this class allows to cache Parcelables, mapped by unique UUIDs,
  * which are written to the parcel instead of the whole Parcelable.
  */
-public class ParcelableCache<E extends Object> {
+public class ParcelableCache<E> {
 
     private static final UUID NULL_UUID = new UUID(0, 0);
 
@@ -39,7 +37,7 @@ public class ParcelableCache<E extends Object> {
      * This is used such that when we become parceled, we are
      * well below the 1 MB boundary that is specified.
      */
-    private ConcurrentHashMap<UUID, E> dehydratedLogs = new ConcurrentHashMap<>();
+    private ConcurrentHashMap<UUID, E> objectCache = new ConcurrentHashMap<>();
 
     /**
      * Dehydrate a Parcelable (such that it is available after deparcelization)
@@ -52,9 +50,9 @@ public class ParcelableCache<E extends Object> {
         if (parcelable == null) {
             return NULL_UUID;
         } else {
-            UUID ticket = UUID.randomUUID();
+            UUID uuid = UUID.randomUUID();
-            dehydratedLogs.put(ticket, parcelable);
+            objectCache.put(uuid, parcelable);
-            return ticket;
+            return uuid;
         }
     }
 
@@ -63,53 +61,34 @@ public class ParcelableCache<E extends Object> {
      * invalidating its place in the dehydration pool.
      * This is used such that when parcelized, the Parcelable is no larger than 1 MB.
      *
-     * @param ticket A UUID ticket that identifies the log in question.
+     * @param uuid A UUID ticket that identifies the log in question.
      * @return An OperationLog.
      */
-    private E rehydrateParcelable(UUID ticket) {
+    private E rehydrateParcelable(UUID uuid) {
         // UUID.equals isn't well documented; we use compareTo instead.
-        if (NULL_UUID.compareTo(ticket) == 0) {
+        if (NULL_UUID.compareTo(uuid) == 0) {
             return null;
         } else {
-            E parcelable = dehydratedLogs.get(ticket);
+            E parcelable = objectCache.get(uuid);
-            dehydratedLogs.remove(ticket);
+            objectCache.remove(uuid);
             return parcelable;
         }
     }
 
-    public E readFromIntentAndGetFromCache(Intent data, String key1, String key2) {
-        if (!data.getExtras().containsKey(key1) || !data.getExtras().containsKey(key2)) {
-            return null;
-        }
-        long mostSig = data.getLongExtra(key1, 0);
-        long leastSig = data.getLongExtra(key2, 0);
-        UUID mTicket = new UUID(mostSig, leastSig);
-        // fetch the dehydrated log out of storage (this removes it from the dehydration pool)
-        return rehydrateParcelable(mTicket);
-    }
-
     public E readFromParcelAndGetFromCache(Parcel source) {
         long mostSig = source.readLong();
         long leastSig = source.readLong();
         UUID mTicket = new UUID(mostSig, leastSig);
-        // fetch the dehydrated log out of storage (this removes it from the dehydration pool)
+        // fetch the dehydrated parcelable out of storage (this removes it from the dehydration pool)
         return rehydrateParcelable(mTicket);
     }
 
     public void cacheAndWriteToParcel(E parcelable, Parcel dest) {
-        // Get a ticket for our log.
+        // Get a ticket for our parcelable.
         UUID mTicket = dehydrateParcelable(parcelable);
         // And write out the UUID most and least significant bits.
         dest.writeLong(mTicket.getMostSignificantBits());
         dest.writeLong(mTicket.getLeastSignificantBits());
     }
 
-    public void cacheAndWriteToIntent(E parcelable, Intent data, String key1, String key2) {
-        // Get a ticket for our log.
-        UUID mTicket = dehydrateParcelable(parcelable);
-        // And write out the UUID most and least significant bits.
-        data.putExtra(key1, mTicket.getMostSignificantBits());
-        data.putExtra(key2, mTicket.getLeastSignificantBits());
-    }
-
 }