How to implement five different encryption modes for AES in Java?

In Java, you can implement five encryption modes for AES using Java Cryptography Architecture (JCA). Here are some example codes:

1. ECB, which stands for Electronic Codebook Mode

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
import java.util.Base64;

public class AESExample {
    public static void main(String[] args) throws Exception {
        String plaintext = "Hello, World!";
        String key = "0123456789abcdef"; // 16字节的AES密钥

        SecretKeySpec secretKey = new SecretKeySpec(key.getBytes(), "AES");
        Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
        cipher.init(Cipher.ENCRYPT_MODE, secretKey);

        byte[] encryptedBytes = cipher.doFinal(plaintext.getBytes());
        String encryptedText = Base64.getEncoder().encodeToString(encryptedBytes);

        System.out.println("Encrypted Text: " + encryptedText);
    }
}

1. Cipher Block Chaining Mode (CBC) – mode of operation for a block cipher algorithm that uses feedback from the previous cipher block to encrypt the current block

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.util.Base64;

public class AESExample {
    public static void main(String[] args) throws Exception {
        String plaintext = "Hello, World!";
        String key = "0123456789abcdef"; // 16字节的AES密钥
        String iv = "fedcba9876543210"; // 16字节的初始化向量

        SecretKeySpec secretKey = new SecretKeySpec(key.getBytes(), "AES");
        IvParameterSpec ivSpec = new IvParameterSpec(iv.getBytes());
        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        cipher.init(Cipher.ENCRYPT_MODE, secretKey, ivSpec);

        byte[] encryptedBytes = cipher.doFinal(plaintext.getBytes());
        String encryptedText = Base64.getEncoder().encodeToString(encryptedBytes);

        System.out.println("Encrypted Text: " + encryptedText);
    }
}

1. Cipher Feedback Mode (CFB)

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.util.Base64;

public class AESExample {
    public static void main(String[] args) throws Exception {
        String plaintext = "Hello, World!";
        String key = "0123456789abcdef"; // 16字节的AES密钥
        String iv = "fedcba9876543210"; // 16字节的初始化向量

        SecretKeySpec secretKey = new SecretKeySpec(key.getBytes(), "AES");
        IvParameterSpec ivSpec = new IvParameterSpec(iv.getBytes());
        Cipher cipher = Cipher.getInstance("AES/CFB/PKCS5Padding");
        cipher.init(Cipher.ENCRYPT_MODE, secretKey, ivSpec);

        byte[] encryptedBytes = cipher.doFinal(plaintext.getBytes());
        String encryptedText = Base64.getEncoder().encodeToString(encryptedBytes);

        System.out.println("Encrypted Text: " + encryptedText);
    }
}

1. Output Feedback Mode (OFB) refers to the mode of providing feedback on the output.

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.util.Base64;

public class AESExample {
    public static void main(String[] args) throws Exception {
        String plaintext = "Hello, World!";
        String key = "0123456789abcdef"; // 16字节的AES密钥
        String iv = "fedcba9876543210"; // 16字节的初始化向量

        SecretKeySpec secretKey = new SecretKeySpec(key.getBytes(), "AES");
        IvParameterSpec ivSpec = new IvParameterSpec(iv.getBytes());
        Cipher cipher = Cipher.getInstance("AES/OFB/PKCS5Padding");
        cipher.init(Cipher.ENCRYPT_MODE, secretKey, ivSpec);

        byte[] encryptedBytes = cipher.doFinal(plaintext.getBytes());
        String encryptedText = Base64.getEncoder().encodeToString(encryptedBytes);

        System.out.println("Encrypted Text: " + encryptedText);
    }
}

1. Counter Mode (CTR)

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.util.Base64;

public class AESExample {
    public static void main(String[] args) throws Exception {
        String plaintext = "Hello, World!";
        String key = "0123456789abcdef"; // 16字节的AES密钥
        String iv = "fedcba9876543210"; // 16字节的初始化向量

        SecretKeySpec secretKey = new SecretKeySpec(key.getBytes(), "