add in-app billing donation stuff

9 files changed, 1393 insertions, 5 deletions

diff --git a/src/com/android/vending/billing/IMarketBillingService.aidl b/src/com/android/vending/billing/IMarketBillingService.aidl
new file mode 100644
index 00000000..6884b41f
--- /dev/null
+++ b/src/com/android/vending/billing/IMarketBillingService.aidl
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2010 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.vending.billing;
+
+import android.os.Bundle;
+
+interface IMarketBillingService {
+    /** Given the arguments in bundle form, returns a bundle for results. */
+    Bundle sendBillingRequest(in Bundle bundle);
+}
diff --git a/src/org/fox/ttrss/BillingConstants.java b/src/org/fox/ttrss/BillingConstants.java
new file mode 100644
index 00000000..ea8b454c
--- /dev/null
+++ b/src/org/fox/ttrss/BillingConstants.java
@@ -0,0 +1,63 @@
+package org.fox.ttrss;

+

+

+public class BillingConstants {

+

+	// The response codes for a request, defined by Android Market.

+	public enum ResponseCode {

+		RESULT_OK, 

+		RESULT_USER_CANCELED, 

+		RESULT_SERVICE_UNAVAILABLE, 

+		RESULT_BILLING_UNAVAILABLE, 

+		RESULT_ITEM_UNAVAILABLE, 

+		RESULT_DEVELOPER_ERROR, 

+		RESULT_ERROR;

+

+		// Converts from an ordinal value to the ResponseCode

+		public static ResponseCode valueOf(int index) {

+			ResponseCode[] values = ResponseCode.values();

+			if (index < 0 || index >= values.length) {

+				return RESULT_ERROR;

+			}

+			return values[index];

+		}

+	}

+

+	// The possible states of an in-app purchase, as defined by Android Market.

+    public enum PurchaseState {

+        // Responses to requestPurchase or restoreTransactions.

+        PURCHASED,   // User was charged for the order.

+        CANCELED,    // The charge failed on the server.

+        REFUNDED;    // User received a refund for the order.

+

+        // Converts from an ordinal value to the PurchaseState

+        public static PurchaseState valueOf(int index) {

+            PurchaseState[] values = PurchaseState.values();

+            if (index < 0 || index >= values.length) {

+                return CANCELED;

+            }

+            return values[index];

+        }

+    }

+	

+	// These are the names of the extras that are passed in an intent from

+    // Market to this application and cannot be changed.

+    public static final String NOTIFICATION_ID = "notification_id";

+    public static final String INAPP_SIGNED_DATA = "inapp_signed_data";

+    public static final String INAPP_SIGNATURE = "inapp_signature";

+    public static final String INAPP_REQUEST_ID = "request_id";

+    public static final String INAPP_RESPONSE_CODE = "response_code";

+	

+	// Intent actions that we send from the BillingReceiver to the

+	// BillingService. Defined by this application.

+	public static final String ACTION_CONFIRM_NOTIFICATION = "com.example.dungeons.CONFIRM_NOTIFICATION";

+	public static final String ACTION_GET_PURCHASE_INFORMATION = "com.example.dungeons.GET_PURCHASE_INFORMATION";

+	public static final String ACTION_RESTORE_TRANSACTIONS = "com.example.dungeons.RESTORE_TRANSACTIONS";

+

+	// Intent actions that we receive in the BillingReceiver from Market.

+	// These are defined by Market and cannot be changed.

+	public static final String ACTION_NOTIFY = "com.android.vending.billing.IN_APP_NOTIFY";

+	public static final String ACTION_RESPONSE_CODE = "com.android.vending.billing.RESPONSE_CODE";

+	public static final String ACTION_PURCHASE_STATE_CHANGED = "com.android.vending.billing.PURCHASE_STATE_CHANGED";

+	

+}

diff --git a/src/org/fox/ttrss/BillingHelper.java b/src/org/fox/ttrss/BillingHelper.java
new file mode 100644
index 00000000..e29fd2f7
--- /dev/null
+++ b/src/org/fox/ttrss/BillingHelper.java
@@ -0,0 +1,267 @@
+package org.fox.ttrss;

+

+import java.util.ArrayList;

+

+import android.app.PendingIntent;

+import android.app.PendingIntent.CanceledException;

+import android.content.Context;

+import android.content.Intent;

+import android.os.Bundle;

+import android.os.Handler;

+import android.os.RemoteException;

+import android.util.Log;

+

+import com.android.vending.billing.IMarketBillingService;

+import org.fox.ttrss.BillingSecurity.VerifiedPurchase;

+import org.fox.ttrss.BillingConstants.ResponseCode;

+

+public class BillingHelper {

+

+	private static final String TAG = "BillingService";

+	

+	private static IMarketBillingService mService;

+	private static Context mContext;

+	private static Handler mCompletedHandler;

+	

+	protected static VerifiedPurchase latestPurchase;

+	

+	protected static void instantiateHelper(Context context, IMarketBillingService service) {

+		mService = service;

+		mContext = context;

+	}

+

+	protected static void setCompletedHandler(Handler handler){

+		mCompletedHandler = handler;

+	}

+	

+	protected static boolean isBillingSupported() {

+		if (amIDead()) {

+			return false;

+		}

+		Bundle request = makeRequestBundle("CHECK_BILLING_SUPPORTED");

+		if (mService != null) {

+			try {

+				Bundle response = mService.sendBillingRequest(request);

+				ResponseCode code = ResponseCode.valueOf((Integer) response.get("RESPONSE_CODE"));

+				Log.i(TAG, "isBillingSupported response was: " + code.toString());

+				if (ResponseCode.RESULT_OK.equals(code)) {

+					return true;

+				} else {

+					return false;

+				}

+			} catch (RemoteException e) {

+				Log.e(TAG, "isBillingSupported response was: RemoteException", e);

+				return false;

+			}

+		} else {

+			Log.i(TAG, "isBillingSupported response was: BillingService.mService = null");

+			return false;

+		}

+	}

+	

+	/**

+	 * A REQUEST_PURCHASE request also triggers two asynchronous responses (broadcast intents). 

+	 * First, the Android Market application sends a RESPONSE_CODE broadcast intent, which provides error information about the request. (which I ignore)

+	 * Next, if the request was successful, the Android Market application sends an IN_APP_NOTIFY broadcast intent. 

+	 * This message contains a notification ID, which you can use to retrieve the transaction details for the REQUEST_PURCHASE

+	 * @param activityContext

+	 * @param itemId

+	 */

+	protected static void requestPurchase(Context activityContext, String itemId){

+		if (amIDead()) {

+			return;

+		}

+		Log.i(TAG, "requestPurchase()");

+		Bundle request = makeRequestBundle("REQUEST_PURCHASE");

+		request.putString("ITEM_ID", itemId);

+		try {

+			Bundle response = mService.sendBillingRequest(request);

+			

+			//The RESPONSE_CODE key provides you with the status of the request

+			Integer responseCodeIndex 	= (Integer) response.get("RESPONSE_CODE");

+			//The PURCHASE_INTENT key provides you with a PendingIntent, which you can use to launch the checkout UI

+			PendingIntent pendingIntent = (PendingIntent) response.get("PURCHASE_INTENT");

+			//The REQUEST_ID key provides you with a unique request identifier for the request

+			Long requestIndentifier 	= (Long) response.get("REQUEST_ID");

+			Log.i(TAG, "current request is:" + requestIndentifier);

+			BillingConstants.ResponseCode responseCode = BillingConstants.ResponseCode.valueOf(responseCodeIndex);

+			Log.i(TAG, "REQUEST_PURCHASE Sync Response code: "+responseCode.toString());

+			

+			startBuyPageActivity(pendingIntent, new Intent(), activityContext);

+		} catch (RemoteException e) {

+			Log.e(TAG, "Failed, internet error maybe", e);

+			Log.e(TAG, "Billing supported: "+isBillingSupported());

+		}

+	}

+	

+	/**

+	 * A GET_PURCHASE_INFORMATION request also triggers two asynchronous responses (broadcast intents). 

+	 * First, the Android Market application sends a RESPONSE_CODE broadcast intent, which provides status and error information about the request.  (which I ignore)

+	 * Next, if the request was successful, the Android Market application sends a PURCHASE_STATE_CHANGED broadcast intent. 

+	 * This message contains detailed transaction information. 

+	 * The transaction information is contained in a signed JSON string (unencrypted). 

+	 * The message includes the signature so you can verify the integrity of the signed string

+	 * @param notifyIds

+	 */

+	protected static void getPurchaseInformation(String[] notifyIds){

+		if (amIDead()) {

+			return;

+		}

+		Log.i(TAG, "getPurchaseInformation()");

+		Bundle request = makeRequestBundle("GET_PURCHASE_INFORMATION");

+		// The REQUEST_NONCE key contains a cryptographically secure nonce (number used once) that you must generate.

+		// The Android Market application returns this nonce with the PURCHASE_STATE_CHANGED broadcast intent so you can verify the integrity of the transaction information.

+		request.putLong("NONCE", BillingSecurity.generateNonce());

+		// The NOTIFY_IDS key contains an array of notification IDs, which you received in the IN_APP_NOTIFY broadcast intent.

+		request.putStringArray("NOTIFY_IDS", notifyIds);

+		try {

+			Bundle response = mService.sendBillingRequest(request);

+			

+			//The REQUEST_ID key provides you with a unique request identifier for the request

+			Long requestIndentifier 	= (Long) response.get("REQUEST_ID");

+			Log.i(TAG, "current request is:" + requestIndentifier);

+			//The RESPONSE_CODE key provides you with the status of the request

+			Integer responseCodeIndex 	= (Integer) response.get("RESPONSE_CODE");

+			BillingConstants.ResponseCode responseCode = BillingConstants.ResponseCode.valueOf(responseCodeIndex);

+			Log.i(TAG, "GET_PURCHASE_INFORMATION Sync Response code: "+responseCode.toString());

+			

+		} catch (RemoteException e) {

+			Log.e(TAG, "Failed, internet error maybe", e);

+			Log.e(TAG, "Billing supported: "+isBillingSupported());

+		}

+	}

+

+	/**

+	 * To acknowledge that you received transaction information you send a

+	 * CONFIRM_NOTIFICATIONS request.

+	 * 

+	 * A CONFIRM_NOTIFICATIONS request triggers a single asynchronous response�a RESPONSE_CODE broadcast intent. 

+	 * This broadcast intent provides status and error information about the request.

+	 * 

+	 * Note: As a best practice, you should not send a CONFIRM_NOTIFICATIONS request for a purchased item until you have delivered the item to the user. 

+	 * This way, if your application crashes or something else prevents your application from delivering the product,

+	 * your application will still receive an IN_APP_NOTIFY broadcast intent from Android Market indicating that you need to deliver the product

+	 * @param notifyIds

+	 */

+	protected static void confirmTransaction(String[] notifyIds) {

+		if (amIDead()) {

+			return;

+		}

+		Log.i(TAG, "confirmTransaction()");

+		Bundle request = makeRequestBundle("CONFIRM_NOTIFICATIONS");

+		request.putStringArray("NOTIFY_IDS", notifyIds);

+		try {

+			Bundle response = mService.sendBillingRequest(request);

+

+			//The REQUEST_ID key provides you with a unique request identifier for the request

+			Long requestIndentifier 	= (Long) response.get("REQUEST_ID");

+			Log.i(TAG, "current request is:" + requestIndentifier);

+			

+			//The RESPONSE_CODE key provides you with the status of the request

+			Integer responseCodeIndex 	= (Integer) response.get("RESPONSE_CODE");

+			BillingConstants.ResponseCode responseCode = BillingConstants.ResponseCode.valueOf(responseCodeIndex);

+			

+			Log.i(TAG, "CONFIRM_NOTIFICATIONS Sync Response code: "+responseCode.toString());

+		} catch (RemoteException e) {

+			Log.e(TAG, "Failed, internet error maybe", e);

+			Log.e(TAG, "Billing supported: " + isBillingSupported());

+		}

+	}

+	

+	/**

+	 * 

+	 * Can be used for when a user has reinstalled the app to give back prior purchases. 

+	 * if an item for sale's purchase type is "managed per user account" this means google will have a record ofthis transaction

+	 * 

+	 * A RESTORE_TRANSACTIONS request also triggers two asynchronous responses (broadcast intents). 

+	 * First, the Android Market application sends a RESPONSE_CODE broadcast intent, which provides status and error information about the request. 

+	 * Next, if the request was successful, the Android Market application sends a PURCHASE_STATE_CHANGED broadcast intent. 

+	 * This message contains the detailed transaction information. The transaction information is contained in a signed JSON string (unencrypted).

+	 * The message includes the signature so you can verify the integrity of the signed string

+	 * @param nonce

+	 */

+	protected static void restoreTransactionInformation(Long nonce) {

+		if (amIDead()) {

+			return;

+		}

+		Log.i(TAG, "confirmTransaction()");

+		Bundle request = makeRequestBundle("RESTORE_TRANSACTIONS");

+		// The REQUEST_NONCE key contains a cryptographically secure nonce (number used once) that you must generate

+		request.putLong("NONCE", nonce);

+		try {

+			Bundle response = mService.sendBillingRequest(request);

+

+			//The REQUEST_ID key provides you with a unique request identifier for the request

+			Long requestIndentifier 	= (Long) response.get("REQUEST_ID");

+			Log.i(TAG, "current request is:" + requestIndentifier);

+			

+			//The RESPONSE_CODE key provides you with the status of the request

+			Integer responseCodeIndex 	= (Integer) response.get("RESPONSE_CODE");

+			BillingConstants.ResponseCode responseCode = BillingConstants.ResponseCode.valueOf(responseCodeIndex);

+			Log.i(TAG, "RESTORE_TRANSACTIONS Sync Response code: "+responseCode.toString());

+		} catch (RemoteException e) {

+			Log.e(TAG, "Failed, internet error maybe", e);

+			Log.e(TAG, "Billing supported: " + isBillingSupported());

+		}

+	}

+	

+	private static boolean amIDead() {

+		if (mService == null || mContext == null) {

+			Log.e(TAG, "BillingHelper not fully instantiated");

+			return true;

+		} else {

+			return false;

+		}

+	}

+

+	private static Bundle makeRequestBundle(String method) {

+		Bundle request = new Bundle();

+		request.putString("BILLING_REQUEST", method);

+		request.putInt("API_VERSION", 1);

+		request.putString("PACKAGE_NAME", mContext.getPackageName());

+		return request;

+	}

+	

+	/**

+	 * 

+	 * 

+	 * You must launch the pending intent from an activity context and not an application context

+	 * You cannot use the singleTop launch mode to launch the pending intent

+	 * @param pendingIntent

+	 * @param intent

+	 * @param context

+	 */

+	private static void startBuyPageActivity(PendingIntent pendingIntent, Intent intent, Context context){

+		//TODO add above 2.0 implementation with reflection, for now just using 1.6 implem

+		

+		// This is on Android 1.6. The in-app checkout page activity will be on its

+	    // own separate activity stack instead of on the activity stack of

+	    // the application.

+		try {

+			pendingIntent.send(context, 0, intent);			

+		} catch (CanceledException e){

+			Log.e(TAG, "startBuyPageActivity CanceledException");

+		}

+	}

+

+	protected static void verifyPurchase(String signedData, String signature) {

+		ArrayList<VerifiedPurchase> purchases = BillingSecurity.verifyPurchase(signedData, signature);

+		latestPurchase = purchases.get(0);

+		

+		confirmTransaction(new String[]{latestPurchase.notificationId});

+		

+		if(mCompletedHandler != null){

+			mCompletedHandler.sendEmptyMessage(0);

+		} else {

+			Log.e(TAG, "verifyPurchase error. Handler not instantiated. Have you called setCompletedHandler()?");

+		}

+	}

+	

+	public static void stopService(){

+		mContext.stopService(new Intent(mContext, BillingService.class));

+		mService = null;

+		mContext = null;

+		mCompletedHandler = null;

+		Log.i(TAG, "Stopping Service");

+	}

+}

diff --git a/src/org/fox/ttrss/BillingReceiver.java b/src/org/fox/ttrss/BillingReceiver.java
new file mode 100644
index 00000000..42cd5df6
--- /dev/null
+++ b/src/org/fox/ttrss/BillingReceiver.java
@@ -0,0 +1,57 @@
+package org.fox.ttrss;

+

+import static org.fox.ttrss.BillingConstants.*;

+

+import java.util.ArrayList;

+

+import android.content.BroadcastReceiver;

+import android.content.Context;

+import android.content.Intent;

+import android.os.Message;

+import android.util.Log;

+

+import org.fox.ttrss.BillingConstants;

+import org.fox.ttrss.BillingSecurity.VerifiedPurchase;

+

+public class BillingReceiver extends BroadcastReceiver {

+

+	private static final String TAG = "BillingService";

+

+	@Override

+	public void onReceive(Context context, Intent intent) {

+		String action = intent.getAction();

+		Log.i(TAG, "Received action: " + action);

+        if (ACTION_PURCHASE_STATE_CHANGED.equals(action)) {

+            String signedData = intent.getStringExtra(INAPP_SIGNED_DATA);

+            String signature = intent.getStringExtra(INAPP_SIGNATURE);

+            purchaseStateChanged(context, signedData, signature);

+        } else if (ACTION_NOTIFY.equals(action)) {

+            String notifyId = intent.getStringExtra(NOTIFICATION_ID);

+            notify(context, notifyId);

+        } else if (ACTION_RESPONSE_CODE.equals(action)) {

+            long requestId = intent.getLongExtra(INAPP_REQUEST_ID, -1);

+            int responseCodeIndex = intent.getIntExtra(INAPP_RESPONSE_CODE, BillingConstants.ResponseCode.RESULT_ERROR.ordinal());

+            checkResponseCode(context, requestId, responseCodeIndex);

+        } else {

+           Log.e(TAG, "unexpected action: " + action);

+        }

+	}

+

+

+	private void purchaseStateChanged(Context context, String signedData, String signature) {

+		Log.i(TAG, "purchaseStateChanged got signedData: " + signedData);

+		Log.i(TAG, "purchaseStateChanged got signature: " + signature);

+		BillingHelper.verifyPurchase(signedData, signature);

+	}

+	

+	private void notify(Context context, String notifyId) {

+		Log.i(TAG, "notify got id: " + notifyId);

+		String[] notifyIds = {notifyId};

+		BillingHelper.getPurchaseInformation(notifyIds);

+	}

+	

+	private void checkResponseCode(Context context, long requestId, int responseCodeIndex) {

+		Log.i(TAG, "checkResponseCode got requestId: " + requestId);

+		Log.i(TAG, "checkResponseCode got responseCode: " + BillingConstants.ResponseCode.valueOf(responseCodeIndex));

+	}

+}
\ No newline at end of file
diff --git a/src/org/fox/ttrss/BillingSecurity.java b/src/org/fox/ttrss/BillingSecurity.java
new file mode 100644
index 00000000..26e19b3e
--- /dev/null
+++ b/src/org/fox/ttrss/BillingSecurity.java
@@ -0,0 +1,258 @@
+// Copyright 2010 Google Inc. All Rights Reserved.
+
+package org.fox.ttrss;
+
+import java.security.InvalidKeyException;
+import java.security.KeyFactory;
+import java.security.NoSuchAlgorithmException;
+import java.security.PublicKey;
+import java.security.SecureRandom;
+import java.security.Signature;
+import java.security.SignatureException;
+import java.security.spec.InvalidKeySpecException;
+import java.security.spec.X509EncodedKeySpec;
+import java.util.ArrayList;
+import java.util.HashSet;
+
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import android.text.TextUtils;
+import android.util.Log;
+
+import org.fox.ttrss.BillingConstants.PurchaseState;
+import org.fox.ttrss.util.Base64;
+import org.fox.ttrss.util.Base64DecoderException;
+
+/**
+ * Security-related methods. For a secure implementation, all of this code
+ * should be implemented on a server that communicates with the application on
+ * the device. For the sake of simplicity and clarity of this example, this code
+ * is included here and is executed on the device. If you must verify the
+ * purchases on the phone, you should obfuscate this code to make it harder for
+ * an attacker to replace the code with stubs that treat all purchases as
+ * verified.
+ */
+public class BillingSecurity {
+	private static final String TAG = "BillingService";
+
+	private static final String KEY_FACTORY_ALGORITHM = "RSA";
+	private static final String SIGNATURE_ALGORITHM = "SHA1withRSA";
+	private static final SecureRandom RANDOM = new SecureRandom();
+
+	/**
+	 * This keeps track of the nonces that we generated and sent to the server.
+	 * We need to keep track of these until we get back the purchase state and
+	 * send a confirmation message back to Android Market. If we are killed and
+	 * lose this list of nonces, it is not fatal. Android Market will send us a
+	 * new "notify" message and we will re-generate a new nonce. This has to be
+	 * "static" so that the {@link BillingReceiver} can check if a nonce exists.
+	 */
+	private static HashSet<Long> sKnownNonces = new HashSet<Long>();
+
+	/**
+	 * A class to hold the verified purchase information.
+	 */
+	public static class VerifiedPurchase {
+		public PurchaseState purchaseState;
+		public String notificationId;
+		public String productId;
+		public String orderId;
+		public long purchaseTime;
+		public String developerPayload;
+
+		public VerifiedPurchase(PurchaseState purchaseState, String notificationId, String productId, String orderId, long purchaseTime,
+				String developerPayload) {
+			this.purchaseState = purchaseState;
+			this.notificationId = notificationId;
+			this.productId = productId;
+			this.orderId = orderId;
+			this.purchaseTime = purchaseTime;
+			this.developerPayload = developerPayload;
+		}
+		
+		public boolean isPurchased(){
+			return purchaseState.equals(PurchaseState.PURCHASED);
+		}
+		
+		
+	}
+
+	/** Generates a nonce (a random number used once). */
+	public static long generateNonce() {
+		long nonce = RANDOM.nextLong();
+		Log.i(TAG, "Nonce generateD: "+nonce);
+		sKnownNonces.add(nonce);
+		return nonce;
+	}
+
+	public static void removeNonce(long nonce) {
+		sKnownNonces.remove(nonce);
+	}
+
+	public static boolean isNonceKnown(long nonce) {
+		return sKnownNonces.contains(nonce);
+	}
+
+	/**
+	 * Verifies that the data was signed with the given signature, and returns
+	 * the list of verified purchases. The data is in JSON format and contains a
+	 * nonce (number used once) that we generated and that was signed (as part
+	 * of the whole data string) with a private key. The data also contains the
+	 * {@link PurchaseState} and product ID of the purchase. In the general
+	 * case, there can be an array of purchase transactions because there may be
+	 * delays in processing the purchase on the backend and then several
+	 * purchases can be batched together.
+	 * 
+	 * @param signedData
+	 *            the signed JSON string (signed, not encrypted)
+	 * @param signature
+	 *            the signature for the data, signed with the private key
+	 */
+	public static ArrayList<VerifiedPurchase> verifyPurchase(String signedData, String signature) {
+		if (signedData == null) {
+			Log.e(TAG, "data is null");
+			return null;
+		}
+		Log.i(TAG, "signedData: " + signedData);
+		boolean verified = false;
+		if (!TextUtils.isEmpty(signature)) {
+			/**
+			 * Compute your public key (that you got from the Android Market
+			 * publisher site).
+			 * 
+			 * Instead of just storing the entire literal string here embedded
+			 * in the program, construct the key at runtime from pieces or use
+			 * bit manipulation (for example, XOR with some other string) to
+			 * hide the actual key. The key itself is not secret information,
+			 * but we don't want to make it easy for an adversary to replace the
+			 * public key with one of their own and then fake messages from the
+			 * server.
+			 * 
+			 * Generally, encryption keys / passwords should only be kept in
+			 * memory long enough to perform the operation they need to perform.
+			 */
+			String base64EncodedPublicKey = "MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEApLWBv8eFC4f7h6gz3VE87XX2nqJB2KL2yNnNawmgaL/0nd6nXvVRiZ3iXLLP9k8RpLJ6rZPV778z8WzDLZATV3b2nh21KgjSNoG4em1oSf7pW4+AujqjLfNVRsXoJIWG+OMMd9o9l/D2YJTCXzSvgFIfF5EJRg6APZHEVrVJo8iXwnYM1tFfLjPfp10MtjLmD5tZW8o3hTmXJ3ZMDI12PL22G4KaE+BuQqI6PZ22m/pA85R6AuhNo2IUSE4XFUE8i7ANWDvdfDzQ5J0TTWAeHmUQCstdZ48z+6AjqD3L2omS/dKoBnlYxEUZms3iUa1/Co40nWU7sc2hqpmfNiG5oQIDAQAB";
+			PublicKey key = BillingSecurity.generatePublicKey(base64EncodedPublicKey);
+			verified = BillingSecurity.verify(key, signedData, signature);
+			if (!verified) {
+				Log.w(TAG, "signature does not match data.");
+				return null;
+			}
+		}
+
+		JSONObject jObject;
+		JSONArray jTransactionsArray = null;
+		int numTransactions = 0;
+		long nonce = 0L;
+		try {
+			jObject = new JSONObject(signedData);
+
+			// The nonce might be null if the user backed out of the buy page.
+			nonce = jObject.optLong("nonce");
+			jTransactionsArray = jObject.optJSONArray("orders");
+			if (jTransactionsArray != null) {
+				numTransactions = jTransactionsArray.length();
+			}
+		} catch (JSONException e) {
+			return null;
+		}
+
+		if (!BillingSecurity.isNonceKnown(nonce)) {
+			Log.w(TAG, "Nonce not found: " + nonce);
+			return null;
+		}
+
+		ArrayList<VerifiedPurchase> purchases = new ArrayList<VerifiedPurchase>();
+		try {
+			for (int i = 0; i < numTransactions; i++) {
+				JSONObject jElement = jTransactionsArray.getJSONObject(i);
+				int response = jElement.getInt("purchaseState");
+				PurchaseState purchaseState = PurchaseState.valueOf(response);
+				String productId = jElement.getString("productId");
+				String packageName = jElement.getString("packageName");
+				long purchaseTime = jElement.getLong("purchaseTime");
+				String orderId = jElement.optString("orderId", "");
+				String notifyId = null;
+				if (jElement.has("notificationId")) {
+					notifyId = jElement.getString("notificationId");
+				}
+				String developerPayload = jElement.optString("developerPayload", null);
+
+				// If the purchase state is PURCHASED, then we require a
+				// verified nonce.
+				if (purchaseState == PurchaseState.PURCHASED && !verified) {
+					continue;
+				}
+				purchases.add(new VerifiedPurchase(purchaseState, notifyId, productId, orderId, purchaseTime, developerPayload));
+			}
+		} catch (JSONException e) {
+			Log.e(TAG, "JSON exception: ", e);
+			return null;
+		}
+		removeNonce(nonce);
+		return purchases;
+	}
+
+	/**
+	 * Generates a PublicKey instance from a string containing the
+	 * Base64-encoded public key.
+	 * 
+	 * @param encodedPublicKey
+	 *            Base64-encoded public key
+	 * @throws IllegalArgumentException
+	 *             if encodedPublicKey is invalid
+	 */
+	public static PublicKey generatePublicKey(String encodedPublicKey) {
+		try {
+			byte[] decodedKey = Base64.decode(encodedPublicKey);
+			KeyFactory keyFactory = KeyFactory.getInstance(KEY_FACTORY_ALGORITHM);
+			return keyFactory.generatePublic(new X509EncodedKeySpec(decodedKey));
+		} catch (NoSuchAlgorithmException e) {
+			throw new RuntimeException(e);
+		} catch (InvalidKeySpecException e) {
+			Log.e(TAG, "Invalid key specification.");
+			throw new IllegalArgumentException(e);
+		} catch (Base64DecoderException e) {
+			Log.e(TAG, "Base64DecoderException.", e);
+			return null;
+		}
+	}
+
+	/**
+	 * Verifies that the signature from the server matches the computed
+	 * signature on the data. Returns true if the data is correctly signed.
+	 * 
+	 * @param publicKey
+	 *            public key associated with the developer account
+	 * @param signedData
+	 *            signed data from server
+	 * @param signature
+	 *            server signature
+	 * @return true if the data and signature match
+	 */
+	public static boolean verify(PublicKey publicKey, String signedData, String signature) {
+		Log.i(TAG, "signature: " + signature);
+		Signature sig;
+		try {
+			sig = Signature.getInstance(SIGNATURE_ALGORITHM);
+			sig.initVerify(publicKey);
+			sig.update(signedData.getBytes());
+			if (!sig.verify(Base64.decode(signature))) {
+				Log.e(TAG, "Signature verification failed.");
+				return false;
+			}
+			return true;
+		} catch (NoSuchAlgorithmException e) {
+			Log.e(TAG, "NoSuchAlgorithmException.");
+		} catch (InvalidKeyException e) {
+			Log.e(TAG, "Invalid key specification.");
+		} catch (SignatureException e) {
+			Log.e(TAG, "Signature exception.");
+		}  catch (Base64DecoderException e) {
+			Log.e(TAG, "Base64DecoderException.", e);
+		}
+		return false;
+	}
+}
diff --git a/src/org/fox/ttrss/BillingService.java b/src/org/fox/ttrss/BillingService.java
new file mode 100644
index 00000000..e003df32
--- /dev/null
+++ b/src/org/fox/ttrss/BillingService.java
@@ -0,0 +1,60 @@
+package org.fox.ttrss;

+

+import android.app.Service;

+import android.content.ComponentName;

+import android.content.Context;

+import android.content.Intent;

+import android.content.ServiceConnection;

+import android.os.IBinder;

+import android.util.Log;

+

+import com.android.vending.billing.IMarketBillingService;

+

+public class BillingService extends Service implements ServiceConnection{

+	

+	private static final String TAG = "BillingService";

+	

+	/** The service connection to the remote MarketBillingService. */

+	private IMarketBillingService mService;

+	

+	@Override

+	public void onCreate() {

+		super.onCreate();

+		Log.i(TAG, "Service starting with onCreate");

+		

+		try {

+			boolean bindResult = bindService(new Intent("com.android.vending.billing.MarketBillingService.BIND"), this, Context.BIND_AUTO_CREATE);

+			if(bindResult){

+				Log.i(TAG,"Market Billing Service Successfully Bound");

+			} else {

+				Log.e(TAG,"Market Billing Service could not be bound.");

+				//TODO stop user continuing

+			}

+		} catch (SecurityException e){

+			Log.e(TAG,"Market Billing Service could not be bound. SecurityException: "+e);

+			//TODO stop user continuing

+		}

+	}

+	

+	public void setContext(Context context) {

+        attachBaseContext(context);

+    }

+	

+	@Override

+	public IBinder onBind(Intent intent) {

+		return null;

+	}

+

+	@Override

+	public void onServiceConnected(ComponentName name, IBinder service) {

+		Log.i(TAG, "Market Billing Service Connected.");

+		mService = IMarketBillingService.Stub.asInterface(service);

+		BillingHelper.instantiateHelper(getBaseContext(), mService);

+	}

+

+	@Override

+	public void onServiceDisconnected(ComponentName name) {

+		

+	}

+

+}

diff --git a/src/org/fox/ttrss/MainActivity.java b/src/org/fox/ttrss/MainActivity.java
index dd3295c8..5d7ecd09 100644
--- a/src/org/fox/ttrss/MainActivity.java
+++ b/src/org/fox/ttrss/MainActivity.java
@@ -23,6 +23,7 @@ import android.database.sqlite.SQLiteDatabase;
 import android.net.ConnectivityManager;
 import android.net.NetworkInfo;
 import android.os.Bundle;
+import android.os.Handler;
 import android.preference.PreferenceManager;
 import android.support.v4.app.Fragment;
 import android.support.v4.app.FragmentActivity;
@@ -69,6 +70,7 @@ public class MainActivity extends FragmentActivity implements OnlineServices {
 	private boolean m_isLoggingIn = false;
 	private boolean m_isOffline = false;
 	private boolean m_offlineModeReady = false;
+	private int m_selectedProduct = -1;
 
 	private SQLiteDatabase m_readableDb;
 	private SQLiteDatabase m_writableDb;
@@ -443,7 +445,7 @@ public class MainActivity extends FragmentActivity implements OnlineServices {
 		}
 
 		super.onCreate(savedInstanceState);
-
+	
 		m_themeName = m_prefs.getString("theme", "THEME_DARK");
 
 		if (savedInstanceState != null) {
@@ -882,6 +884,45 @@ public class MainActivity extends FragmentActivity implements OnlineServices {
 				.findFragmentById(R.id.headlines_fragment);
 
 		switch (item.getItemId()) {
+		case R.id.donate:
+			if (true) {
+				CharSequence[] items = { "Silver Donation ($2)", "Gold Donation ($5)", "Platinum Donation ($10)" };
+			
+				Dialog dialog = new Dialog(MainActivity.this);
+				AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this)
+						.setTitle(R.string.donate_select)
+						.setSingleChoiceItems(items, -1, new DialogInterface.OnClickListener() {
+							
+							@Override
+							public void onClick(DialogInterface dialog, int which) {
+								m_selectedProduct = which;
+							}
+						}).setNegativeButton(R.string.dialog_close, new OnClickListener() {
+							
+							@Override
+							public void onClick(DialogInterface dialog, int which) {
+								dialog.cancel();
+							}					
+						}).setPositiveButton(R.string.donate_do, new OnClickListener() {
+							
+							@Override
+							public void onClick(DialogInterface dialog, int which) {
+								if (m_selectedProduct != -1 && m_selectedProduct < 3) {
+									CharSequence[] products = { "donation_silver", "donation_gold", "donation_platinum2" };
+									
+									Log.d(TAG, "Selected product: " + products[m_selectedProduct]);
+
+									BillingHelper.requestPurchase(MainActivity.this, (String) products[m_selectedProduct]);
+									
+									dialog.dismiss();									
+								}
+							}
+						});
+	
+				dialog = builder.create();
+				dialog.show();
+			}
+			return true;
 		case android.R.id.home:
 			goBack(false);
 			return true;
@@ -1130,7 +1171,7 @@ public class MainActivity extends FragmentActivity implements OnlineServices {
 							
 							Dialog dialog = new Dialog(MainActivity.this);
 							AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this)
-									.setTitle("Set labels")
+									.setTitle(R.string.article_set_labels)
 									.setMultiChoiceItems(items, checkedItems, new OnMultiChoiceClickListener() {
 										
 										@Override
@@ -1152,7 +1193,7 @@ public class MainActivity extends FragmentActivity implements OnlineServices {
 											req.execute(map);
 											
 										}
-									}).setPositiveButton("Close", new OnClickListener() {
+									}).setPositiveButton(R.string.dialog_close, new OnClickListener() {
 										
 										@Override
 										public void onClick(DialogInterface dialog, int which) {
@@ -1358,7 +1399,9 @@ public class MainActivity extends FragmentActivity implements OnlineServices {
 				}
 				
 				m_menu.findItem(R.id.set_labels).setEnabled(m_apiLevel >= 1);
-				
+
+				m_menu.findItem(R.id.donate).setVisible(BillingHelper.isBillingSupported());
+								
 			} else {
 				m_menu.setGroupVisible(R.id.menu_group_logged_in, false);
 				m_menu.setGroupVisible(R.id.menu_group_logged_out, true);
@@ -1410,8 +1453,10 @@ public class MainActivity extends FragmentActivity implements OnlineServices {
 		
 		m_isOffline = false;
 
+		startService(new Intent(MainActivity.this, BillingService.class));
+		
 		initMainMenu();
-
+		
 		if (m_refreshTask != null) {
 			m_refreshTask.cancel();
 			m_refreshTask = null;
diff --git a/src/org/fox/ttrss/util/Base64.java b/src/org/fox/ttrss/util/Base64.java
new file mode 100644
index 00000000..5c8136db
--- /dev/null
+++ b/src/org/fox/ttrss/util/Base64.java
@@ -0,0 +1,582 @@
+// Portions copyright 2002, Google, Inc.
+//
+// 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 org.fox.ttrss.util;
+
+// This code was converted from code at http://iharder.sourceforge.net/base64/
+// Lots of extraneous features were removed.
+/* The original code said:
+ * <p>
+ * I am placing this code in the Public Domain. Do with it as you will.
+ * This software comes with no guarantees or warranties but with
+ * plenty of well-wishing instead!
+ * Please visit
+ * <a href="http://iharder.net/xmlizable">http://iharder.net/xmlizable</a>
+ * periodically to check for updates or to contribute improvements.
+ * </p>
+ *
+ * @author Robert Harder
+ * @author [email protected]
+ * @version 1.3
+ */
+
+/**
+ * Base64 converter class. This code is not a complete MIME encoder; it simply
+ * converts binary data to base64 data and back.
+ * 
+ * <p>
+ * Note {@link CharBase64} is a GWT-compatible implementation of this class.
+ */
+public class Base64 {
+	/** Specify encoding (value is {@code true}). */
+	public final static boolean ENCODE = true;
+
+	/** Specify decoding (value is {@code false}). */
+	public final static boolean DECODE = false;
+
+	/** The equals sign (=) as a byte. */
+	private final static byte EQUALS_SIGN = (byte) '=';
+
+	/** The new line character (\n) as a byte. */
+	private final static byte NEW_LINE = (byte) '\n';
+
+	/**
+	 * The 64 valid Base64 values.
+	 */
+	private final static byte[] ALPHABET = { (byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D', (byte) 'E', (byte) 'F', (byte) 'G',
+			(byte) 'H', (byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L', (byte) 'M', (byte) 'N', (byte) 'O', (byte) 'P', (byte) 'Q',
+			(byte) 'R', (byte) 'S', (byte) 'T', (byte) 'U', (byte) 'V', (byte) 'W', (byte) 'X', (byte) 'Y', (byte) 'Z', (byte) 'a',
+			(byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f', (byte) 'g', (byte) 'h', (byte) 'i', (byte) 'j', (byte) 'k',
+			(byte) 'l', (byte) 'm', (byte) 'n', (byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r', (byte) 's', (byte) 't', (byte) 'u',
+			(byte) 'v', (byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z', (byte) '0', (byte) '1', (byte) '2', (byte) '3', (byte) '4',
+			(byte) '5', (byte) '6', (byte) '7', (byte) '8', (byte) '9', (byte) '+', (byte) '/' };
+
+	/**
+	 * The 64 valid web safe Base64 values.
+	 */
+	private final static byte[] WEBSAFE_ALPHABET = { (byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D', (byte) 'E', (byte) 'F', (byte) 'G',
+			(byte) 'H', (byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L', (byte) 'M', (byte) 'N', (byte) 'O', (byte) 'P', (byte) 'Q',
+			(byte) 'R', (byte) 'S', (byte) 'T', (byte) 'U', (byte) 'V', (byte) 'W', (byte) 'X', (byte) 'Y', (byte) 'Z', (byte) 'a',
+			(byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f', (byte) 'g', (byte) 'h', (byte) 'i', (byte) 'j', (byte) 'k',
+			(byte) 'l', (byte) 'm', (byte) 'n', (byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r', (byte) 's', (byte) 't', (byte) 'u',
+			(byte) 'v', (byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z', (byte) '0', (byte) '1', (byte) '2', (byte) '3', (byte) '4',
+			(byte) '5', (byte) '6', (byte) '7', (byte) '8', (byte) '9', (byte) '-', (byte) '_' };
+
+	/**
+	 * Translates a Base64 value to either its 6-bit reconstruction value or a
+	 * negative number indicating some other meaning.
+	 **/
+	private final static byte[] DECODABET = { -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal
+			// 0
+			// -
+			// 8
+			-5, -5, // Whitespace: Tab and Linefeed
+			-9, -9, // Decimal 11 - 12
+			-5, // Whitespace: Carriage Return
+			-9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 14 -
+			// 26
+			-9, -9, -9, -9, -9, // Decimal 27 - 31
+			-5, // Whitespace: Space
+			-9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 33 - 42
+			62, // Plus sign at decimal 43
+			-9, -9, -9, // Decimal 44 - 46
+			63, // Slash at decimal 47
+			52, 53, 54, 55, 56, 57, 58, 59, 60, 61, // Numbers zero through nine
+			-9, -9, -9, // Decimal 58 - 60
+			-1, // Equals sign at decimal 61
+			-9, -9, -9, // Decimal 62 - 64
+			0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, // Letters 'A' through
+			// 'N'
+			14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // Letters 'O'
+			// through 'Z'
+			-9, -9, -9, -9, -9, -9, // Decimal 91 - 96
+			26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, // Letters 'a'
+			// through 'm'
+			39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, // Letters 'n'
+			// through 'z'
+			-9, -9, -9, -9, -9 // Decimal 123 - 127
+	/*
+	 * ,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 128 - 139
+	 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 140 - 152
+	 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 153 - 165
+	 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 166 - 178
+	 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 179 - 191
+	 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 192 - 204
+	 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 205 - 217
+	 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 218 - 230
+	 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 231 - 243
+	 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9 // Decimal 244 - 255
+	 */
+	};
+
+	/** The web safe decodabet */
+	private final static byte[] WEBSAFE_DECODABET = { -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal
+			// 0
+			// -
+			// 8
+			-5, -5, // Whitespace: Tab and Linefeed
+			-9, -9, // Decimal 11 - 12
+			-5, // Whitespace: Carriage Return
+			-9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 14 -
+			// 26
+			-9, -9, -9, -9, -9, // Decimal 27 - 31
+			-5, // Whitespace: Space
+			-9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 33 - 44
+			62, // Dash '-' sign at decimal 45
+			-9, -9, // Decimal 46-47
+			52, 53, 54, 55, 56, 57, 58, 59, 60, 61, // Numbers zero through nine
+			-9, -9, -9, // Decimal 58 - 60
+			-1, // Equals sign at decimal 61
+			-9, -9, -9, // Decimal 62 - 64
+			0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, // Letters 'A' through
+			// 'N'
+			14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // Letters 'O'
+			// through 'Z'
+			-9, -9, -9, -9, // Decimal 91-94
+			63, // Underscore '_' at decimal 95
+			-9, // Decimal 96
+			26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, // Letters 'a'
+			// through 'm'
+			39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, // Letters 'n'
+			// through 'z'
+			-9, -9, -9, -9, -9 // Decimal 123 - 127
+	/*
+	 * ,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 128 - 139
+	 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 140 - 152
+	 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 153 - 165
+	 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 166 - 178
+	 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 179 - 191
+	 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 192 - 204
+	 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 205 - 217
+	 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 218 - 230
+	 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 231 - 243
+	 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9 // Decimal 244 - 255
+	 */
+	};
+
+	// Indicates white space in encoding
+	private final static byte WHITE_SPACE_ENC = -5;
+	// Indicates equals sign in encoding
+	private final static byte EQUALS_SIGN_ENC = -1;
+
+	/** Defeats instantiation. */
+	private Base64() {
+	}
+
+	/*   ******** E N C O D I N G M E T H O D S ******** */
+
+	/**
+	 * Encodes up to three bytes of the array <var>source</var> and writes the
+	 * resulting four Base64 bytes to <var>destination</var>. The source and
+	 * destination arrays can be manipulated anywhere along their length by
+	 * specifying <var>srcOffset</var> and <var>destOffset</var>. This method
+	 * does not check to make sure your arrays are large enough to accommodate
+	 * <var>srcOffset</var> + 3 for the <var>source</var> array or
+	 * <var>destOffset</var> + 4 for the <var>destination</var> array. The
+	 * actual number of significant bytes in your array is given by
+	 * <var>numSigBytes</var>.
+	 * 
+	 * @param source
+	 *            the array to convert
+	 * @param srcOffset
+	 *            the index where conversion begins
+	 * @param numSigBytes
+	 *            the number of significant bytes in your array
+	 * @param destination
+	 *            the array to hold the conversion
+	 * @param destOffset
+	 *            the index where output will be put
+	 * @param alphabet
+	 *            is the encoding alphabet
+	 * @return the <var>destination</var> array
+	 * @since 1.3
+	 */
+	private static byte[] encode3to4(byte[] source, int srcOffset, int numSigBytes, byte[] destination, int destOffset, byte[] alphabet) {
+		// 1 2 3
+		// 01234567890123456789012345678901 Bit position
+		// --------000000001111111122222222 Array position from threeBytes
+		// --------| || || || | Six bit groups to index alphabet
+		// >>18 >>12 >> 6 >> 0 Right shift necessary
+		// 0x3f 0x3f 0x3f Additional AND
+
+		// Create buffer with zero-padding if there are only one or two
+		// significant bytes passed in the array.
+		// We have to shift left 24 in order to flush out the 1's that appear
+		// when Java treats a value as negative that is cast from a byte to an
+		// int.
+		int inBuff = (numSigBytes > 0 ? ((source[srcOffset] << 24) >>> 8) : 0)
+				| (numSigBytes > 1 ? ((source[srcOffset + 1] << 24) >>> 16) : 0)
+				| (numSigBytes > 2 ? ((source[srcOffset + 2] << 24) >>> 24) : 0);
+
+		switch (numSigBytes) {
+		case 3:
+			destination[destOffset] = alphabet[(inBuff >>> 18)];
+			destination[destOffset + 1] = alphabet[(inBuff >>> 12) & 0x3f];
+			destination[destOffset + 2] = alphabet[(inBuff >>> 6) & 0x3f];
+			destination[destOffset + 3] = alphabet[(inBuff) & 0x3f];
+			return destination;
+		case 2:
+			destination[destOffset] = alphabet[(inBuff >>> 18)];
+			destination[destOffset + 1] = alphabet[(inBuff >>> 12) & 0x3f];
+			destination[destOffset + 2] = alphabet[(inBuff >>> 6) & 0x3f];
+			destination[destOffset + 3] = EQUALS_SIGN;
+			return destination;
+		case 1:
+			destination[destOffset] = alphabet[(inBuff >>> 18)];
+			destination[destOffset + 1] = alphabet[(inBuff >>> 12) & 0x3f];
+			destination[destOffset + 2] = EQUALS_SIGN;
+			destination[destOffset + 3] = EQUALS_SIGN;
+			return destination;
+		default:
+			return destination;
+		} // end switch
+	} // end encode3to4
+
+	/**
+	 * Encodes a byte array into Base64 notation. Equivalent to calling {@code
+	 * encodeBytes(source, 0, source.length)}
+	 * 
+	 * @param source
+	 *            The data to convert
+	 * @since 1.4
+	 */
+	public static String encode(byte[] source) {
+		return encode(source, 0, source.length, ALPHABET, true);
+	}
+
+	/**
+	 * Encodes a byte array into web safe Base64 notation.
+	 * 
+	 * @param source
+	 *            The data to convert
+	 * @param doPadding
+	 *            is {@code true} to pad result with '=' chars if it does not
+	 *            fall on 3 byte boundaries
+	 */
+	public static String encodeWebSafe(byte[] source, boolean doPadding) {
+		return encode(source, 0, source.length, WEBSAFE_ALPHABET, doPadding);
+	}
+
+	/**
+	 * Encodes a byte array into Base64 notation.
+	 * 
+	 * @param source
+	 *            the data to convert
+	 * @param off
+	 *            offset in array where conversion should begin
+	 * @param len
+	 *            length of data to convert
+	 * @param alphabet
+	 *            the encoding alphabet
+	 * @param doPadding
+	 *            is {@code true} to pad result with '=' chars if it does not
+	 *            fall on 3 byte boundaries
+	 * @since 1.4
+	 */
+	public static String encode(byte[] source, int off, int len, byte[] alphabet, boolean doPadding) {
+		byte[] outBuff = encode(source, off, len, alphabet, Integer.MAX_VALUE);
+		int outLen = outBuff.length;
+
+		// If doPadding is false, set length to truncate '='
+		// padding characters
+		while (doPadding == false && outLen > 0) {
+			if (outBuff[outLen - 1] != '=') {
+				break;
+			}
+			outLen -= 1;
+		}
+
+		return new String(outBuff, 0, outLen);
+	}
+
+	/**
+	 * Encodes a byte array into Base64 notation.
+	 * 
+	 * @param source
+	 *            the data to convert
+	 * @param off
+	 *            offset in array where conversion should begin
+	 * @param len
+	 *            length of data to convert
+	 * @param alphabet
+	 *            is the encoding alphabet
+	 * @param maxLineLength
+	 *            maximum length of one line.
+	 * @return the BASE64-encoded byte array
+	 */
+	public static byte[] encode(byte[] source, int off, int len, byte[] alphabet, int maxLineLength) {
+		int lenDiv3 = (len + 2) / 3; // ceil(len / 3)
+		int len43 = lenDiv3 * 4;
+		byte[] outBuff = new byte[len43 // Main 4:3
+				+ (len43 / maxLineLength)]; // New lines
+
+		int d = 0;
+		int e = 0;
+		int len2 = len - 2;
+		int lineLength = 0;
+		for (; d < len2; d += 3, e += 4) {
+
+			// The following block of code is the same as
+			// encode3to4( source, d + off, 3, outBuff, e, alphabet );
+			// but inlined for faster encoding (~20% improvement)
+			int inBuff = ((source[d + off] << 24) >>> 8) | ((source[d + 1 + off] << 24) >>> 16) | ((source[d + 2 + off] << 24) >>> 24);
+			outBuff[e] = alphabet[(inBuff >>> 18)];
+			outBuff[e + 1] = alphabet[(inBuff >>> 12) & 0x3f];
+			outBuff[e + 2] = alphabet[(inBuff >>> 6) & 0x3f];
+			outBuff[e + 3] = alphabet[(inBuff) & 0x3f];
+
+			lineLength += 4;
+			if (lineLength == maxLineLength) {
+				outBuff[e + 4] = NEW_LINE;
+				e++;
+				lineLength = 0;
+			} // end if: end of line
+		} // end for: each piece of array
+
+		if (d < len) {
+			encode3to4(source, d + off, len - d, outBuff, e, alphabet);
+
+			lineLength += 4;
+			if (lineLength == maxLineLength) {
+				// Add a last newline
+				outBuff[e + 4] = NEW_LINE;
+				e++;
+			}
+			e += 4;
+		}
+
+		assert (e == outBuff.length);
+		return outBuff;
+	}
+
+	/*   ******** D E C O D I N G M E T H O D S ******** */
+
+	/**
+	 * Decodes four bytes from array <var>source</var> and writes the resulting
+	 * bytes (up to three of them) to <var>destination</var>. The source and
+	 * destination arrays can be manipulated anywhere along their length by
+	 * specifying <var>srcOffset</var> and <var>destOffset</var>. This method
+	 * does not check to make sure your arrays are large enough to accommodate
+	 * <var>srcOffset</var> + 4 for the <var>source</var> array or
+	 * <var>destOffset</var> + 3 for the <var>destination</var> array. This
+	 * method returns the actual number of bytes that were converted from the
+	 * Base64 encoding.
+	 * 
+	 * 
+	 * @param source
+	 *            the array to convert
+	 * @param srcOffset
+	 *            the index where conversion begins
+	 * @param destination
+	 *            the array to hold the conversion
+	 * @param destOffset
+	 *            the index where output will be put
+	 * @param decodabet
+	 *            the decodabet for decoding Base64 content
+	 * @return the number of decoded bytes converted
+	 * @since 1.3
+	 */
+	private static int decode4to3(byte[] source, int srcOffset, byte[] destination, int destOffset, byte[] decodabet) {
+		// Example: Dk==
+		if (source[srcOffset + 2] == EQUALS_SIGN) {
+			int outBuff = ((decodabet[source[srcOffset]] << 24) >>> 6) | ((decodabet[source[srcOffset + 1]] << 24) >>> 12);
+
+			destination[destOffset] = (byte) (outBuff >>> 16);
+			return 1;
+		} else if (source[srcOffset + 3] == EQUALS_SIGN) {
+			// Example: DkL=
+			int outBuff = ((decodabet[source[srcOffset]] << 24) >>> 6) | ((decodabet[source[srcOffset + 1]] << 24) >>> 12)
+					| ((decodabet[source[srcOffset + 2]] << 24) >>> 18);
+
+			destination[destOffset] = (byte) (outBuff >>> 16);
+			destination[destOffset + 1] = (byte) (outBuff >>> 8);
+			return 2;
+		} else {
+			// Example: DkLE
+			int outBuff = ((decodabet[source[srcOffset]] << 24) >>> 6) | ((decodabet[source[srcOffset + 1]] << 24) >>> 12)
+					| ((decodabet[source[srcOffset + 2]] << 24) >>> 18) | ((decodabet[source[srcOffset + 3]] << 24) >>> 24);
+
+			destination[destOffset] = (byte) (outBuff >> 16);
+			destination[destOffset + 1] = (byte) (outBuff >> 8);
+			destination[destOffset + 2] = (byte) (outBuff);
+			return 3;
+		}
+	} // end decodeToBytes
+
+	/**
+	 * Decodes data from Base64 notation.
+	 * 
+	 * @param s
+	 *            the string to decode (decoded in default encoding)
+	 * @return the decoded data
+	 * @since 1.4
+	 */
+	public static byte[] decode(String s) throws Base64DecoderException {
+		byte[] bytes = s.getBytes();
+		return decode(bytes, 0, bytes.length);
+	}
+
+	/**
+	 * Decodes data from web safe Base64 notation. Web safe encoding uses '-'
+	 * instead of '+', '_' instead of '/'
+	 * 
+	 * @param s
+	 *            the string to decode (decoded in default encoding)
+	 * @return the decoded data
+	 */
+	public static byte[] decodeWebSafe(String s) throws Base64DecoderException {
+		byte[] bytes = s.getBytes();
+		return decodeWebSafe(bytes, 0, bytes.length);
+	}
+
+	/**
+	 * Decodes Base64 content in byte array format and returns the decoded byte
+	 * array.
+	 * 
+	 * @param source
+	 *            The Base64 encoded data
+	 * @return decoded data
+	 * @since 1.3
+	 * @throws Base64DecoderException
+	 */
+	public static byte[] decode(byte[] source) throws Base64DecoderException {
+		return decode(source, 0, source.length);
+	}
+
+	/**
+	 * Decodes web safe Base64 content in byte array format and returns the
+	 * decoded data. Web safe encoding uses '-' instead of '+', '_' instead of
+	 * '/'
+	 * 
+	 * @param source
+	 *            the string to decode (decoded in default encoding)
+	 * @return the decoded data
+	 */
+	public static byte[] decodeWebSafe(byte[] source) throws Base64DecoderException {
+		return decodeWebSafe(source, 0, source.length);
+	}
+
+	/**
+	 * Decodes Base64 content in byte array format and returns the decoded byte
+	 * array.
+	 * 
+	 * @param source
+	 *            the Base64 encoded data
+	 * @param off
+	 *            the offset of where to begin decoding
+	 * @param len
+	 *            the length of characters to decode
+	 * @return decoded data
+	 * @since 1.3
+	 * @throws Base64DecoderException
+	 */
+	public static byte[] decode(byte[] source, int off, int len) throws Base64DecoderException {
+		return decode(source, off, len, DECODABET);
+	}
+
+	/**
+	 * Decodes web safe Base64 content in byte array format and returns the
+	 * decoded byte array. Web safe encoding uses '-' instead of '+', '_'
+	 * instead of '/'
+	 * 
+	 * @param source
+	 *            the Base64 encoded data
+	 * @param off
+	 *            the offset of where to begin decoding
+	 * @param len
+	 *            the length of characters to decode
+	 * @return decoded data
+	 */
+	public static byte[] decodeWebSafe(byte[] source, int off, int len) throws Base64DecoderException {
+		return decode(source, off, len, WEBSAFE_DECODABET);
+	}
+
+	/**
+	 * Decodes Base64 content using the supplied decodabet and returns the
+	 * decoded byte array.
+	 * 
+	 * @param source
+	 *            the Base64 encoded data
+	 * @param off
+	 *            the offset of where to begin decoding
+	 * @param len
+	 *            the length of characters to decode
+	 * @param decodabet
+	 *            the decodabet for decoding Base64 content
+	 * @return decoded data
+	 */
+	public static byte[] decode(byte[] source, int off, int len, byte[] decodabet) throws Base64DecoderException {
+		int len34 = len * 3 / 4;
+		byte[] outBuff = new byte[2 + len34]; // Upper limit on size of output
+		int outBuffPosn = 0;
+
+		byte[] b4 = new byte[4];
+		int b4Posn = 0;
+		int i = 0;
+		byte sbiCrop = 0;
+		byte sbiDecode = 0;
+		for (i = 0; i < len; i++) {
+			sbiCrop = (byte) (source[i + off] & 0x7f); // Only the low seven
+			// bits
+			sbiDecode = decodabet[sbiCrop];
+
+			if (sbiDecode >= WHITE_SPACE_ENC) { // White space Equals sign or
+				// better
+				if (sbiDecode >= EQUALS_SIGN_ENC) {
+					// An equals sign (for padding) must not occur at position 0
+					// or 1
+					// and must be the last byte[s] in the encoded value
+					if (sbiCrop == EQUALS_SIGN) {
+						int bytesLeft = len - i;
+						byte lastByte = (byte) (source[len - 1 + off] & 0x7f);
+						if (b4Posn == 0 || b4Posn == 1) {
+							throw new Base64DecoderException("invalid padding byte '=' at byte offset " + i);
+						} else if ((b4Posn == 3 && bytesLeft > 2) || (b4Posn == 4 && bytesLeft > 1)) {
+							throw new Base64DecoderException("padding byte '=' falsely signals end of encoded value " + "at offset " + i);
+						} else if (lastByte != EQUALS_SIGN && lastByte != NEW_LINE) {
+							throw new Base64DecoderException("encoded value has invalid trailing byte");
+						}
+						break;
+					}
+
+					b4[b4Posn++] = sbiCrop;
+					if (b4Posn == 4) {
+						outBuffPosn += decode4to3(b4, 0, outBuff, outBuffPosn, decodabet);
+						b4Posn = 0;
+					}
+				}
+			} else {
+				throw new Base64DecoderException("Bad Base64 input character at " + i + ": " + source[i + off] + "(decimal)");
+			}
+		}
+
+		// Because web safe encoding allows non padding base64 encodes, we
+		// need to pad the rest of the b4 buffer with equal signs when
+		// b4Posn != 0. There can be at most 2 equal signs at the end of
+		// four characters, so the b4 buffer must have two or three
+		// characters. This also catches the case where the input is
+		// padded with EQUALS_SIGN
+		if (b4Posn != 0) {
+			if (b4Posn == 1) {
+				// Ensure you have set your public key
+				throw new Base64DecoderException("single trailing character at offset " + (len - 1));
+			}
+			b4[b4Posn++] = EQUALS_SIGN;
+			outBuffPosn += decode4to3(b4, 0, outBuff, outBuffPosn, decodabet);
+		}
+
+		byte[] out = new byte[outBuffPosn];
+		System.arraycopy(outBuff, 0, out, 0, outBuffPosn);
+		return out;
+	}
+}
diff --git a/src/org/fox/ttrss/util/Base64DecoderException.java b/src/org/fox/ttrss/util/Base64DecoderException.java
new file mode 100644
index 00000000..7b7be229
--- /dev/null
+++ b/src/org/fox/ttrss/util/Base64DecoderException.java
@@ -0,0 +1,32 @@
+// Copyright 2002, Google, Inc.
+//
+// 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 org.fox.ttrss.util;;
+
+/**
+ * Exception thrown when encountering an invalid Base64 input character.
+ *
+ * @author nelson
+ */
+public class Base64DecoderException extends Exception {
+  public Base64DecoderException() {
+    super();
+  }
+
+  public Base64DecoderException(String s) {
+    super(s);
+  }
+
+  private static final long serialVersionUID = 1L;
+}