Java tutorial
/* * Copyright by the original author or authors. * * 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 cryptwallet; import javafx.application.Platform; import org.bitcoinj.crypto.KeyCrypterScrypt; import com.google.common.primitives.Longs; import com.google.protobuf.ByteString; import javafx.beans.property.ReadOnlyObjectProperty; import javafx.beans.property.SimpleObjectProperty; import javafx.event.ActionEvent; import javafx.fxml.FXML; import javafx.scene.control.Label; import javafx.scene.control.PasswordField; import javafx.scene.control.ProgressIndicator; import javafx.scene.image.ImageView; import javafx.scene.layout.GridPane; import javafx.scene.layout.HBox; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.spongycastle.crypto.params.KeyParameter; import cryptwallet.utils.KeyDerivationTasks; import java.time.Duration; import static com.google.common.base.Preconditions.checkNotNull; import static cryptwallet.utils.GuiUtils.*; /** * User interface for entering a password on demand, e.g. to send money. Also used when encrypting a wallet. Shows a * progress meter as we scrypt the password. */ public class CryptPasswordController { private static final Logger log = LoggerFactory.getLogger(CryptPasswordController.class); @FXML HBox buttonsBox; @FXML PasswordField pass1; @FXML ImageView padlockImage; @FXML ProgressIndicator progressMeter; @FXML GridPane widgetGrid; @FXML Label explanationLabel; public Main.OverlayUI overlayUI; private SimpleObjectProperty<KeyParameter> aesKey = new SimpleObjectProperty<>(); public void initialize() { progressMeter.setOpacity(0); Platform.runLater(pass1::requestFocus); } @FXML void confirmClicked(ActionEvent event) { String password = pass1.getText(); if (password.isEmpty() || password.length() < 4) { informationalAlert("Bad password", "The password you entered is empty or too short."); return; } final KeyCrypterScrypt keyCrypter = (KeyCrypterScrypt) Main.bitcoin.wallet().getKeyCrypter(); checkNotNull(keyCrypter); // We should never arrive at this GUI if the wallet isn't actually encrypted. KeyDerivationTasks tasks = new KeyDerivationTasks(keyCrypter, password, getTargetTime()) { @Override protected final void onFinish(KeyParameter aesKey, int timeTakenMsec) { checkGuiThread(); if (Main.bitcoin.wallet().checkAESKey(aesKey)) { CryptPasswordController.this.aesKey.set(aesKey); } else { log.warn("User entered incorrect password"); fadeOut(progressMeter); fadeIn(widgetGrid); fadeIn(explanationLabel); fadeIn(buttonsBox); informationalAlert("Wrong password", "Please try entering your password again, carefully checking for typos or spelling errors."); } } }; progressMeter.progressProperty().bind(tasks.progress); tasks.start(); fadeIn(progressMeter); fadeOut(widgetGrid); fadeOut(explanationLabel); fadeOut(buttonsBox); } public void cancelClicked(ActionEvent event) { overlayUI.done(); } public ReadOnlyObjectProperty<KeyParameter> aesKeyProperty() { return aesKey; } /////////////////////////////////////////////////////////////////////////////////////////////////////////////////// public static final String TAG = CryptPasswordController.class.getName() + ".target-time"; // Writes the given time to the wallet as a tag so we can find it again in this class. public static void setTargetTime(Duration targetTime) { ByteString bytes = ByteString.copyFrom(Longs.toByteArray(targetTime.toMillis())); Main.bitcoin.wallet().setTag(TAG, bytes); } // Reads target time or throws if not set yet (should never happen). public static Duration getTargetTime() throws IllegalArgumentException { return Duration.ofMillis(Longs.fromByteArray(Main.bitcoin.wallet().getTag(TAG).toByteArray())); } }