Java Security&BouncyCastle API令人困惑和困惑

Question

我一直在尝试理解用于Java的BouncyCastle加密API.不幸的是,我发现Java加密通常被服务提供者接口和术语所掩盖,以至于我无法理解实际做的事情.我已经尝试过反复阅读必要的文档,但它只是难以理解,引入了许多远远超出我认为应该需要的概念.

我真正想要的是一个执行以下操作的类:

public class KeyPair {
    public byte[] public;
    public byte[] private;
}

public class RSACrypto {
    public static KeyPair generateRSAKeyPair() { /*implementation*/}
    public static byte[] encrypt(byte[] data, byte[] publicKey) { /*impl*/}
    public static byte[] decrypt(byte[] encryptedData, byte[] privateKey) { /*impl*/ }
}

如果这是一个非常复杂的问题,请问"我真正想要的一切".关于在Java加密和BouncyCastle上阅读的地方的任何指示都是非常受欢迎的.任何有关Java加密系统实际布局的概述都非常受欢迎.

Answer 1

import java.security.GeneralSecurityException;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.PrivateKey;
import java.security.PublicKey;

import javax.crypto.Cipher;

public class RSACrypto
{

  /* A 1024-bit key will encrypt messages up to 117 bytes long. */
  private static final int KEY_SIZE = 1024;

  private static final String XFORM = 
    "RSA/ECB/OAEPWITHSHA-256ANDMGF1PADDING";

  public static KeyPair generateRSAKeyPair()
    throws GeneralSecurityException
  {
    KeyPairGenerator gen = KeyPairGenerator.getInstance("RSA");
    gen.initialize(KEY_SIZE);
    return gen.generateKeyPair();
  }

  public static byte[] encrypt(byte[] plaintext, PublicKey pub)
    throws GeneralSecurityException
  {
    Cipher cipher = Cipher.getInstance(XFORM);
    cipher.init(Cipher.ENCRYPT_MODE, pub);
    return cipher.doFinal(plaintext);
  }

  public static byte[] decrypt(byte[] ciphertext, PrivateKey pvt)
    throws GeneralSecurityException
  {
    Cipher cipher = Cipher.getInstance(XFORM);
    cipher.init(Cipher.DECRYPT_MODE, pvt);
    return cipher.doFinal(ciphertext);
  }

  public static void main(String... argv)
    throws Exception
  {
    KeyPair pair = RSACrypto.generateRSAKeyPair();
    byte[] plaintext = "A short secret message.".getBytes("UTF-8");
    byte[] ciphertext = RSACrypto.encrypt(plaintext, pair.getPublic());
    byte[] recovered = RSACrypto.decrypt(ciphertext, pair.getPrivate());
    System.out.println(new String(recovered, "UTF-8"));
  }

}

Answer 2

嗯，您尝试过O'Reilly 关于 Java 密码学的书吗？（个人无法保证）