JAVA-8282: Moved 5 articles from core-java-security-2 module to new
module core-java-security-algorithms
This commit is contained in:
sampadawagde
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@ -10,12 +10,7 @@ This module contains articles about core Java Security
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- [SHA-256 and SHA3-256 Hashing in Java](https://www.baeldung.com/sha-256-hashing-java)
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- [Checksums in Java](https://www.baeldung.com/java-checksums)
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- [How to Read PEM File to Get Public and Private Keys](https://www.baeldung.com/java-read-pem-file-keys)
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- [Listing the Available Cipher Algorithms](https://www.baeldung.com/java-list-cipher-algorithms)
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- [Get a List of Trusted Certificates in Java](https://www.baeldung.com/java-list-trusted-certificates)
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- [Security Context Basics: User, Subject and Principal](https://www.baeldung.com/security-context-basics)
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- [Java AES Encryption and Decryption](https://www.baeldung.com/java-aes-encryption-decryption)
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- [InvalidAlgorithmParameterException: Wrong IV Length](https://www.baeldung.com/java-invalidalgorithmparameter-exception)
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- [The java.security.egd JVM Option](https://www.baeldung.com/java-security-egd)
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- [RSA in Java](https://www.baeldung.com/java-rsa)
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- [3DES in Java](https://www.baeldung.com/java-3des)
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- More articles: [[<-- prev]](/core-java-modules/core-java-security)
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@ -1,156 +0,0 @@
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package com.baeldung.aes;
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import javax.crypto.Cipher;
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import javax.crypto.IllegalBlockSizeException;
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import javax.crypto.NoSuchPaddingException;
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import javax.crypto.SecretKey;
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import javax.crypto.BadPaddingException;
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import javax.crypto.KeyGenerator;
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import javax.crypto.SecretKeyFactory;
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import javax.crypto.SealedObject;
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import javax.crypto.spec.IvParameterSpec;
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import javax.crypto.spec.PBEKeySpec;
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import javax.crypto.spec.SecretKeySpec;
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import java.io.File;
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import java.io.FileInputStream;
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import java.io.FileOutputStream;
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import java.io.IOException;
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import java.io.Serializable;
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import java.security.InvalidAlgorithmParameterException;
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import java.security.InvalidKeyException;
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import java.security.NoSuchAlgorithmException;
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import java.security.SecureRandom;
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import java.security.spec.InvalidKeySpecException;
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import java.security.spec.KeySpec;
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import java.util.Base64;
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public class AESUtil {
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public static String encrypt(String algorithm, String input, SecretKey key, IvParameterSpec iv)
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throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidAlgorithmParameterException,
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InvalidKeyException, BadPaddingException, IllegalBlockSizeException {
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Cipher cipher = Cipher.getInstance(algorithm);
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cipher.init(Cipher.ENCRYPT_MODE, key, iv);
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byte[] cipherText = cipher.doFinal(input.getBytes());
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return Base64.getEncoder()
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.encodeToString(cipherText);
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}
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public static String decrypt(String algorithm, String cipherText, SecretKey key, IvParameterSpec iv)
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throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidAlgorithmParameterException,
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InvalidKeyException, BadPaddingException, IllegalBlockSizeException {
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Cipher cipher = Cipher.getInstance(algorithm);
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cipher.init(Cipher.DECRYPT_MODE, key, iv);
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byte[] plainText = cipher.doFinal(Base64.getDecoder()
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.decode(cipherText));
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return new String(plainText);
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}
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public static SecretKey generateKey(int n) throws NoSuchAlgorithmException {
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KeyGenerator keyGenerator = KeyGenerator.getInstance("AES");
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keyGenerator.init(n);
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SecretKey key = keyGenerator.generateKey();
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return key;
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}
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public static SecretKey getKeyFromPassword(String password, String salt)
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throws NoSuchAlgorithmException, InvalidKeySpecException {
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SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA256");
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KeySpec spec = new PBEKeySpec(password.toCharArray(), salt.getBytes(), 65536, 256);
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SecretKey secret = new SecretKeySpec(factory.generateSecret(spec)
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.getEncoded(), "AES");
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return secret;
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}
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public static IvParameterSpec generateIv() {
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byte[] iv = new byte[16];
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new SecureRandom().nextBytes(iv);
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return new IvParameterSpec(iv);
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}
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public static void encryptFile(String algorithm, SecretKey key, IvParameterSpec iv,
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File inputFile, File outputFile) throws IOException, NoSuchPaddingException,
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NoSuchAlgorithmException, InvalidAlgorithmParameterException, InvalidKeyException,
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BadPaddingException, IllegalBlockSizeException {
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Cipher cipher = Cipher.getInstance(algorithm);
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cipher.init(Cipher.ENCRYPT_MODE, key, iv);
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FileInputStream inputStream = new FileInputStream(inputFile);
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FileOutputStream outputStream = new FileOutputStream(outputFile);
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byte[] buffer = new byte[64];
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int bytesRead;
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while ((bytesRead = inputStream.read(buffer)) != -1) {
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byte[] output = cipher.update(buffer, 0, bytesRead);
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if (output != null) {
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outputStream.write(output);
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}
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}
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byte[] outputBytes = cipher.doFinal();
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if (outputBytes != null) {
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outputStream.write(outputBytes);
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}
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inputStream.close();
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outputStream.close();
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}
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public static void decryptFile(String algorithm, SecretKey key, IvParameterSpec iv,
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File encryptedFile, File decryptedFile) throws IOException, NoSuchPaddingException,
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NoSuchAlgorithmException, InvalidAlgorithmParameterException, InvalidKeyException,
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BadPaddingException, IllegalBlockSizeException {
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Cipher cipher = Cipher.getInstance(algorithm);
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cipher.init(Cipher.DECRYPT_MODE, key, iv);
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FileInputStream inputStream = new FileInputStream(encryptedFile);
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FileOutputStream outputStream = new FileOutputStream(decryptedFile);
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byte[] buffer = new byte[64];
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int bytesRead;
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while ((bytesRead = inputStream.read(buffer)) != -1) {
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byte[] output = cipher.update(buffer, 0, bytesRead);
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if (output != null) {
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outputStream.write(output);
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}
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}
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byte[] output = cipher.doFinal();
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if (output != null) {
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outputStream.write(output);
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}
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inputStream.close();
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outputStream.close();
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}
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public static SealedObject encryptObject(String algorithm, Serializable object, SecretKey key,
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IvParameterSpec iv) throws NoSuchPaddingException, NoSuchAlgorithmException,
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InvalidAlgorithmParameterException, InvalidKeyException, IOException, IllegalBlockSizeException {
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Cipher cipher = Cipher.getInstance(algorithm);
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cipher.init(Cipher.ENCRYPT_MODE, key, iv);
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SealedObject sealedObject = new SealedObject(object, cipher);
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return sealedObject;
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}
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public static Serializable decryptObject(String algorithm, SealedObject sealedObject, SecretKey key,
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IvParameterSpec iv) throws NoSuchPaddingException, NoSuchAlgorithmException,
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InvalidAlgorithmParameterException, InvalidKeyException, ClassNotFoundException,
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BadPaddingException, IllegalBlockSizeException, IOException {
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Cipher cipher = Cipher.getInstance(algorithm);
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cipher.init(Cipher.DECRYPT_MODE, key, iv);
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Serializable unsealObject = (Serializable) sealedObject.getObject(cipher);
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return unsealObject;
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}
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public static String encryptPasswordBased(String plainText, SecretKey key, IvParameterSpec iv)
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throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidAlgorithmParameterException,
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InvalidKeyException, BadPaddingException, IllegalBlockSizeException {
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Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
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cipher.init(Cipher.ENCRYPT_MODE, key, iv);
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return Base64.getEncoder()
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.encodeToString(cipher.doFinal(plainText.getBytes()));
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}
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public static String decryptPasswordBased(String cipherText, SecretKey key, IvParameterSpec iv)
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throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidAlgorithmParameterException,
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InvalidKeyException, BadPaddingException, IllegalBlockSizeException {
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Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
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cipher.init(Cipher.DECRYPT_MODE, key, iv);
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return new String(cipher.doFinal(Base64.getDecoder()
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.decode(cipherText)));
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}
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}
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@ -1,40 +0,0 @@
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package com.baeldung.aes;
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import java.io.Serializable;
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import java.util.Objects;
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public class Student implements Serializable {
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private String name;
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private int age;
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public Student(String name, int age) {
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this.name = name;
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this.age = age;
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}
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public String getName() {
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return name;
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}
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public void setName(String name) {
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this.name = name;
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}
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public int getAge() {
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return age;
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}
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public void setAge(int age) {
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this.age = age;
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}
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@Override
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public boolean equals(Object o) {
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if (this == o)
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return true;
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if (o == null || getClass() != o.getClass())
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return false;
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Student student = (Student) o;
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return age == student.age && Objects.equals(name, student.name);
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}
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}
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@ -1,101 +0,0 @@
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package com.baeldung.aes;
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import org.assertj.core.api.WithAssertions;
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import org.junit.jupiter.api.Assertions;
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import org.junit.jupiter.api.Test;
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import javax.crypto.SealedObject;
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import javax.crypto.SecretKey;
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import javax.crypto.spec.IvParameterSpec;
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import javax.crypto.BadPaddingException;
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import javax.crypto.IllegalBlockSizeException;
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import javax.crypto.NoSuchPaddingException;
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import java.io.File;
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import java.io.IOException;
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import java.nio.file.Paths;
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import java.security.InvalidAlgorithmParameterException;
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import java.security.InvalidKeyException;
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import java.security.NoSuchAlgorithmException;
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import java.security.spec.InvalidKeySpecException;
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class AESUtilUnitTest implements WithAssertions {
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@Test
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void givenString_whenEncrypt_thenSuccess()
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throws NoSuchAlgorithmException, IllegalBlockSizeException, InvalidKeyException,
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BadPaddingException, InvalidAlgorithmParameterException, NoSuchPaddingException {
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// given
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String input = "baeldung";
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SecretKey key = AESUtil.generateKey(128);
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IvParameterSpec ivParameterSpec = AESUtil.generateIv();
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String algorithm = "AES/CBC/PKCS5Padding";
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// when
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String cipherText = AESUtil.encrypt(algorithm, input, key, ivParameterSpec);
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String plainText = AESUtil.decrypt(algorithm, cipherText, key, ivParameterSpec);
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// then
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Assertions.assertEquals(input, plainText);
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}
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@Test
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void givenFile_whenEncrypt_thenSuccess()
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throws NoSuchAlgorithmException, IOException, IllegalBlockSizeException, InvalidKeyException,
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BadPaddingException, InvalidAlgorithmParameterException, NoSuchPaddingException {
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// given
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SecretKey key = AESUtil.generateKey(128);
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String algorithm = "AES/CBC/PKCS5Padding";
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IvParameterSpec ivParameterSpec = AESUtil.generateIv();
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File inputFile = Paths.get("src/test/resources/baeldung.txt")
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.toFile();
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File encryptedFile = new File("classpath:baeldung.encrypted");
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File decryptedFile = new File("document.decrypted");
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// when
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AESUtil.encryptFile(algorithm, key, ivParameterSpec, inputFile, encryptedFile);
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AESUtil.decryptFile(algorithm, key, ivParameterSpec, encryptedFile, decryptedFile);
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// then
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assertThat(inputFile).hasSameTextualContentAs(decryptedFile);
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encryptedFile.delete();
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decryptedFile.delete();
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}
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@Test
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void givenObject_whenEncrypt_thenSuccess()
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throws NoSuchAlgorithmException, IllegalBlockSizeException, InvalidKeyException,
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InvalidAlgorithmParameterException, NoSuchPaddingException, IOException, BadPaddingException,
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ClassNotFoundException {
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// given
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Student student = new Student("Baeldung", 20);
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SecretKey key = AESUtil.generateKey(128);
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IvParameterSpec ivParameterSpec = AESUtil.generateIv();
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String algorithm = "AES/CBC/PKCS5Padding";
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// when
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SealedObject sealedObject = AESUtil.encryptObject(algorithm, student, key, ivParameterSpec);
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Student object = (Student) AESUtil.decryptObject(algorithm, sealedObject, key, ivParameterSpec);
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// then
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assertThat(student).isEqualTo(object);
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}
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@Test
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void givenPassword_whenEncrypt_thenSuccess()
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throws InvalidKeySpecException, NoSuchAlgorithmException, IllegalBlockSizeException,
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InvalidKeyException, BadPaddingException, InvalidAlgorithmParameterException, NoSuchPaddingException {
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// given
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String plainText = "www.baeldung.com";
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String password = "baeldung";
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String salt = "12345678";
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IvParameterSpec ivParameterSpec = AESUtil.generateIv();
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SecretKey key = AESUtil.getKeyFromPassword(password, salt);
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// when
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String cipherText = AESUtil.encryptPasswordBased(plainText, key, ivParameterSpec);
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String decryptedCipherText = AESUtil.decryptPasswordBased(cipherText, key, ivParameterSpec);
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// then
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Assertions.assertEquals(plainText, decryptedCipherText);
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}
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}
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@ -1,35 +0,0 @@
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package com.baeldung.cipher;
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import org.junit.jupiter.api.Test;
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import org.slf4j.Logger;
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import org.slf4j.LoggerFactory;
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import java.security.Provider;
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import java.security.Security;
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import java.util.Arrays;
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import java.util.List;
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import java.util.stream.Collectors;
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public class AvailableCiphersUnitTest {
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private final Logger logger = LoggerFactory.getLogger(AvailableCiphersUnitTest.class);
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@Test
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public void whenGetServices_thenGetAllCipherAlgorithms() {
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for (Provider provider : Security.getProviders()) {
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for (Provider.Service service : provider.getServices()) {
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logger.info(service.getAlgorithm());
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}
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}
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}
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@Test
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public void whenGetServicesWithFilter_thenGetAllCompatibleCipherAlgorithms() {
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List<String> algorithms = Arrays.stream(Security.getProviders())
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.flatMap(provider -> provider.getServices().stream())
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.filter(service -> "Cipher".equals(service.getType()))
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.map(Provider.Service::getAlgorithm)
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.collect(Collectors.toList());
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algorithms.forEach(logger::info);
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}
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}
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@ -1,90 +0,0 @@
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package com.baeldung.des;
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import org.junit.jupiter.api.Assertions;
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import org.junit.jupiter.api.Test;
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import javax.crypto.Cipher;
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import javax.crypto.spec.IvParameterSpec;
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import javax.crypto.spec.SecretKeySpec;
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import java.io.BufferedReader;
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import java.io.BufferedWriter;
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import java.io.FileOutputStream;
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import java.io.FileReader;
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import java.nio.charset.StandardCharsets;
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import java.nio.file.Files;
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import java.nio.file.Path;
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public class TripleDESUnitTest {
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@Test
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public void given3DesKey_whenEncryptAndDecryptString_thenCompareResults() throws Exception {
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byte[] secretKey = "9mng65v8jf4lxn93nabf981m".getBytes();
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byte[] iv = "a76nb5h9".getBytes();
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String secretMessage = "Baeldung secret message";
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SecretKeySpec secretKeySpec = new SecretKeySpec(secretKey, "DESede");
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IvParameterSpec ivSpec = new IvParameterSpec(iv);
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Cipher encryptCipher = Cipher.getInstance("DESede/CBC/PKCS5Padding");
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encryptCipher.init(Cipher.ENCRYPT_MODE, secretKeySpec, ivSpec);
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byte[] secretMessagesBytes = secretMessage.getBytes(StandardCharsets.UTF_8);
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byte[] encryptedMessageBytes = encryptCipher.doFinal(secretMessagesBytes);
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Cipher decryptCipher = Cipher.getInstance("DESede/CBC/PKCS5Padding");
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decryptCipher.init(Cipher.DECRYPT_MODE, secretKeySpec, ivSpec);
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byte[] decryptedMessageBytes = decryptCipher.doFinal(encryptedMessageBytes);
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String decryptedMessage = new String(decryptedMessageBytes, StandardCharsets.UTF_8);
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Assertions.assertEquals(secretMessage, decryptedMessage);
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}
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@Test
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public void given3DesKey_whenEncryptAndDecryptFile_thenCompareResults() throws Exception {
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byte[] secretKey = "9mng65v8jf4lxn93nabf981m".getBytes();
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byte[] iv = "a76nb5h9".getBytes();
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SecretKeySpec secretKeySpec = new SecretKeySpec(secretKey, "DESede");
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IvParameterSpec ivSpec = new IvParameterSpec(iv);
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String originalContent = "some secret message";
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Path tempFile = Files.createTempFile("temp", "txt");
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writeString(tempFile, originalContent);
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byte[] fileBytes = Files.readAllBytes(tempFile);
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Cipher encryptCipher = Cipher.getInstance("DESede/CBC/PKCS5Padding");
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encryptCipher.init(Cipher.ENCRYPT_MODE, secretKeySpec, ivSpec);
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byte[] encryptedFileBytes = encryptCipher.doFinal(fileBytes);
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try (FileOutputStream stream = new FileOutputStream(tempFile.toFile())) {
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stream.write(encryptedFileBytes);
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}
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encryptedFileBytes = Files.readAllBytes(tempFile);
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Cipher decryptCipher = Cipher.getInstance("DESede/CBC/PKCS5Padding");
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decryptCipher.init(Cipher.DECRYPT_MODE, secretKeySpec, ivSpec);
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byte[] decryptedFileBytes = decryptCipher.doFinal(encryptedFileBytes);
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try (FileOutputStream stream = new FileOutputStream(tempFile.toFile())) {
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stream.write(decryptedFileBytes);
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}
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String fileContent = readString(tempFile);
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Assertions.assertEquals(originalContent, fileContent);
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}
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private void writeString(Path path, String content) throws Exception {
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try (BufferedWriter writer = Files.newBufferedWriter(path)) {
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writer.write(content);
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}
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}
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private String readString(Path path) throws Exception {
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StringBuilder resultStringBuilder = new StringBuilder();
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try (BufferedReader br = new BufferedReader(new FileReader(path.toFile()))) {
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String line;
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while ((line = br.readLine()) != null) {
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resultStringBuilder.append(line);
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}
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}
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return resultStringBuilder.toString();
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}
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}
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@ -1,92 +0,0 @@
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package com.baeldung.cipher;
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import org.junit.jupiter.api.Assertions;
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import org.junit.jupiter.api.Test;
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|
||||
import javax.crypto.Cipher;
|
||||
import java.io.BufferedReader;
|
||||
import java.io.BufferedWriter;
|
||||
import java.io.FileOutputStream;
|
||||
import java.io.FileReader;
|
||||
import java.nio.charset.StandardCharsets;
|
||||
import java.nio.file.Files;
|
||||
import java.nio.file.Path;
|
||||
import java.security.KeyPair;
|
||||
import java.security.KeyPairGenerator;
|
||||
import java.security.PrivateKey;
|
||||
import java.security.PublicKey;
|
||||
|
||||
public class RsaUnitTest {
|
||||
|
||||
@Test
|
||||
public void givenRsaKeyPair_whenEncryptAndDecryptString_thenCompareResults() throws Exception {
|
||||
KeyPairGenerator generator = KeyPairGenerator.getInstance("RSA");
|
||||
generator.initialize(2048);
|
||||
KeyPair pair = generator.generateKeyPair();
|
||||
PrivateKey privateKey = pair.getPrivate();
|
||||
PublicKey publicKey = pair.getPublic();
|
||||
|
||||
String secretMessage = "Baeldung secret message";
|
||||
Cipher encryptCipher = Cipher.getInstance("RSA");
|
||||
encryptCipher.init(Cipher.ENCRYPT_MODE, publicKey);
|
||||
byte[] secretMessageBytes = secretMessage.getBytes(StandardCharsets.UTF_8);
|
||||
byte[] encryptedMessageBytes = encryptCipher.doFinal(secretMessageBytes);
|
||||
|
||||
Cipher decryptCipher = Cipher.getInstance("RSA");
|
||||
decryptCipher.init(Cipher.DECRYPT_MODE, privateKey);
|
||||
byte[] decryptedMessageBytes = decryptCipher.doFinal(encryptedMessageBytes);
|
||||
String decryptedMessage = new String(decryptedMessageBytes, StandardCharsets.UTF_8);
|
||||
|
||||
Assertions.assertEquals(secretMessage, decryptedMessage);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenRsaKeyPair_whenEncryptAndDecryptFile_thenCompareResults() throws Exception {
|
||||
KeyPairGenerator generator = KeyPairGenerator.getInstance("RSA");
|
||||
generator.initialize(2048);
|
||||
KeyPair pair = generator.generateKeyPair();
|
||||
PrivateKey privateKey = pair.getPrivate();
|
||||
PublicKey publicKey = pair.getPublic();
|
||||
|
||||
String originalContent = "some secret message";
|
||||
Path tempFile = Files.createTempFile("temp", "txt");
|
||||
writeString(tempFile, originalContent);
|
||||
|
||||
byte[] fileBytes = Files.readAllBytes(tempFile);
|
||||
Cipher encryptCipher = Cipher.getInstance("RSA");
|
||||
encryptCipher.init(Cipher.ENCRYPT_MODE, publicKey);
|
||||
byte[] encryptedFileBytes = encryptCipher.doFinal(fileBytes);
|
||||
try (FileOutputStream stream = new FileOutputStream(tempFile.toFile())) {
|
||||
stream.write(encryptedFileBytes);
|
||||
}
|
||||
|
||||
encryptedFileBytes = Files.readAllBytes(tempFile);
|
||||
Cipher decryptCipher = Cipher.getInstance("RSA");
|
||||
decryptCipher.init(Cipher.DECRYPT_MODE, privateKey);
|
||||
byte[] decryptedFileBytes = decryptCipher.doFinal(encryptedFileBytes);
|
||||
try (FileOutputStream stream = new FileOutputStream(tempFile.toFile())) {
|
||||
stream.write(decryptedFileBytes);
|
||||
}
|
||||
|
||||
String fileContent = readString(tempFile);
|
||||
|
||||
Assertions.assertEquals(originalContent, fileContent);
|
||||
}
|
||||
|
||||
private void writeString(Path path, String content) throws Exception {
|
||||
try (BufferedWriter writer = Files.newBufferedWriter(path)) {
|
||||
writer.write(content);
|
||||
}
|
||||
}
|
||||
|
||||
private String readString(Path path) throws Exception {
|
||||
StringBuilder resultStringBuilder = new StringBuilder();
|
||||
try (BufferedReader br = new BufferedReader(new FileReader(path.toFile()))) {
|
||||
String line;
|
||||
while ((line = br.readLine()) != null) {
|
||||
resultStringBuilder.append(line);
|
||||
}
|
||||
}
|
||||
return resultStringBuilder.toString();
|
||||
}
|
||||
}
|
||||
|
|
@ -0,0 +1,11 @@
|
|||
## Core Java Security Algorithms
|
||||
|
||||
This module contains articles about core Java Security Algorithms such as AES, DES, RSA, etc
|
||||
|
||||
### Relevant Articles:
|
||||
|
||||
- [Listing the Available Cipher Algorithms](https://www.baeldung.com/java-list-cipher-algorithms)
|
||||
- [Java AES Encryption and Decryption](https://www.baeldung.com/java-aes-encryption-decryption)
|
||||
- [InvalidAlgorithmParameterException: Wrong IV Length](https://www.baeldung.com/java-invalidalgorithmparameter-exception)
|
||||
- [RSA in Java](https://www.baeldung.com/java-rsa)
|
||||
- [3DES in Java](https://www.baeldung.com/java-3des)
|
||||
Loading…
Reference in New Issue