Java tutorial
/* * Copyright (C) 2012-2013 Dominik Schrmann <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.thialfihar.android.apg.ui.dialog; import android.app.Activity; import android.app.AlertDialog; import android.app.Dialog; import android.content.Context; import android.content.DialogInterface; import android.content.DialogInterface.OnClickListener; import android.os.Bundle; import android.os.Message; import android.os.Messenger; import android.os.RemoteException; import android.support.v4.app.DialogFragment; import android.view.KeyEvent; import android.view.LayoutInflater; import android.view.View; import android.view.WindowManager.LayoutParams; import android.view.inputmethod.EditorInfo; import android.widget.Button; import android.widget.EditText; import android.widget.TextView; import android.widget.TextView.OnEditorActionListener; import android.widget.Toast; import org.spongycastle.openpgp.PGPException; import org.spongycastle.openpgp.PGPPrivateKey; import org.spongycastle.openpgp.PGPSecretKey; import org.spongycastle.openpgp.operator.PBESecretKeyDecryptor; import org.spongycastle.openpgp.operator.jcajce.JcePBESecretKeyDecryptorBuilder; import org.thialfihar.android.apg.Constants; import org.thialfihar.android.apg.Id; import org.thialfihar.android.apg.R; import org.thialfihar.android.apg.pgp.PgpKeyHelper; import org.thialfihar.android.apg.pgp.exception.PgpGeneralException; import org.thialfihar.android.apg.provider.ProviderHelper; import org.thialfihar.android.apg.service.PassphraseCacheService; import org.thialfihar.android.apg.util.Log; public class PassphraseDialogFragment extends DialogFragment implements OnEditorActionListener { private static final String ARG_MESSENGER = "messenger"; private static final String ARG_SECRET_KEY_ID = "secret_key_id"; public static final int MESSAGE_OKAY = 1; public static final int MESSAGE_CANCEL = 2; private Messenger mMessenger; private EditText mPassphraseEditText; private boolean mCanRequestFocus; /** * Creates new instance of this dialog fragment * * @param secretKeyId * secret key id you want to use * @param messenger * to communicate back after caching the passphrase * @return * @throws PgpGeneralException */ public static PassphraseDialogFragment newInstance(Context context, Messenger messenger, long secretKeyId) throws PgpGeneralException { // check if secret key has a passphrase if (!(secretKeyId == Id.key.symmetric || secretKeyId == Id.key.none)) { if (!PassphraseCacheService.hasPassphrase(context, secretKeyId)) { throw new PgpGeneralException("No passphrase! No passphrase dialog needed!"); } } PassphraseDialogFragment frag = new PassphraseDialogFragment(); Bundle args = new Bundle(); args.putLong(ARG_SECRET_KEY_ID, secretKeyId); args.putParcelable(ARG_MESSENGER, messenger); frag.setArguments(args); return frag; } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); } /** * Creates dialog */ @Override public Dialog onCreateDialog(Bundle savedInstanceState) { final Activity activity = getActivity(); final long secretKeyId = getArguments().getLong(ARG_SECRET_KEY_ID); mMessenger = getArguments().getParcelable(ARG_MESSENGER); AlertDialog.Builder alert = new AlertDialog.Builder(activity); alert.setTitle(R.string.title_authentication); final PGPSecretKey secretKey; if (secretKeyId == Id.key.symmetric || secretKeyId == Id.key.none) { secretKey = null; alert.setMessage(R.string.passphrase_for_symmetric_encryption); } else { // TODO: by master key id??? secretKey = PgpKeyHelper.getMasterKey(ProviderHelper.getPGPSecretKeyRingByKeyId(activity, secretKeyId)); // secretKey = PGPHelper.getMasterKey(PGPMain.getSecretKeyRing(secretKeyId)); if (secretKey == null) { alert.setTitle(R.string.title_key_not_found); alert.setMessage(getString(R.string.key_not_found, secretKeyId)); alert.setPositiveButton(android.R.string.ok, new OnClickListener() { public void onClick(DialogInterface dialog, int which) { dismiss(); } }); alert.setCancelable(false); mCanRequestFocus = false; return alert.create(); } String userId = PgpKeyHelper.getMainUserIdSafe(activity, secretKey); Log.d(Constants.TAG, "User id: '" + userId + "'"); alert.setMessage(getString(R.string.passphrase_for, userId)); } LayoutInflater inflater = activity.getLayoutInflater(); View view = inflater.inflate(R.layout.passphrase_dialog, null); alert.setView(view); mPassphraseEditText = (EditText) view.findViewById(R.id.passphrase_passphrase); alert.setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int id) { dismiss(); long curKeyIndex = 1; boolean keyOK = true; String passphrase = mPassphraseEditText.getText().toString(); long keyId; PGPSecretKey clickSecretKey = secretKey; if (clickSecretKey != null) { while (keyOK) { if (clickSecretKey != null) { // check again for loop try { PBESecretKeyDecryptor keyDecryptor = new JcePBESecretKeyDecryptorBuilder() .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME) .build(passphrase.toCharArray()); PGPPrivateKey testKey = clickSecretKey.extractPrivateKey(keyDecryptor); if (testKey == null) { if (!clickSecretKey.isMasterKey()) { Toast.makeText(activity, R.string.error_could_not_extract_private_key, Toast.LENGTH_SHORT).show(); sendMessageToHandler(MESSAGE_CANCEL); return; } else { clickSecretKey = PgpKeyHelper.getKeyNum( ProviderHelper.getPGPSecretKeyRingByKeyId(activity, secretKeyId), curKeyIndex); curKeyIndex++; // does post-increment work like C? continue; } } else { keyOK = false; } } catch (PGPException e) { Toast.makeText(activity, R.string.wrong_passphrase, Toast.LENGTH_SHORT).show(); sendMessageToHandler(MESSAGE_CANCEL); return; } } else { Toast.makeText(activity, R.string.error_could_not_extract_private_key, Toast.LENGTH_SHORT).show(); sendMessageToHandler(MESSAGE_CANCEL); return; // ran out of keys to try } } keyId = secretKey.getKeyID(); } else { keyId = Id.key.symmetric; } // cache the new passphrase Log.d(Constants.TAG, "Everything okay! Caching entered passphrase"); PassphraseCacheService.addCachedPassphrase(activity, keyId, passphrase); if (!keyOK && clickSecretKey.getKeyID() != keyId) { PassphraseCacheService.addCachedPassphrase(activity, clickSecretKey.getKeyID(), passphrase); } sendMessageToHandler(MESSAGE_OKAY); } }); alert.setNegativeButton(android.R.string.cancel, new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int id) { dialog.cancel(); } }); mCanRequestFocus = true; return alert.create(); } @Override public void onActivityCreated(Bundle arg0) { super.onActivityCreated(arg0); if (mCanRequestFocus) { // request focus and open soft keyboard mPassphraseEditText.requestFocus(); getDialog().getWindow().setSoftInputMode(LayoutParams.SOFT_INPUT_STATE_VISIBLE); mPassphraseEditText.setOnEditorActionListener(this); } } @Override public void onCancel(DialogInterface dialog) { super.onCancel(dialog); dismiss(); sendMessageToHandler(MESSAGE_CANCEL); } /** * Associate the "done" button on the soft keyboard with the okay button in the view */ @Override public boolean onEditorAction(TextView v, int actionId, KeyEvent event) { if (EditorInfo.IME_ACTION_DONE == actionId) { AlertDialog dialog = ((AlertDialog) getDialog()); Button bt = dialog.getButton(AlertDialog.BUTTON_POSITIVE); bt.performClick(); return true; } return false; } /** * Send message back to handler which is initialized in a activity * * @param what * Message integer you want to send */ private void sendMessageToHandler(Integer what) { Message msg = Message.obtain(); msg.what = what; try { mMessenger.send(msg); } catch (RemoteException e) { Log.w(Constants.TAG, "Exception sending message, Is handler present?", e); } catch (NullPointerException e) { Log.w(Constants.TAG, "Messenger is null!", e); } } }