Java Security＆BouncyCastle API让人感到困惑和困惑

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*/ } } 

抱歉，如果这是一个非常复杂的问题，可以问为“我真正想要的一切”。 任何关于Java加密和BouncyCastle阅读内容的指针都非常受欢迎。 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，你有没有尝试过关于Java Cryptography的O’Reilly书 ？ （不能亲自担保）

Answer 3

 import java.security.GeneralSecurityException; import java.security.KeyFactory; import java.security.KeyPairGenerator; import java.security.PublicKey; import java.security.interfaces.RSAPrivateKey; import java.security.spec.PKCS8EncodedKeySpec; import java.security.spec.X509EncodedKeySpec; import javax.crypto.Cipher; public class RsaCrypto { private static final int KEY_SIZE = 3072; private static final String TRANSFORMATION = "RSA/ECB/OAEPWITHSHA-256ANDMGF1PADDING"; public static KeyPair generateRSAKeyPair() { try { KeyPairGenerator gen = KeyPairGenerator.getInstance("RSA"); gen.initialize(KEY_SIZE); java.security.KeyPair p = gen.generateKeyPair(); KeyPair pair = new KeyPair(); pair.privateKey = p.getPrivate().getEncoded(); pair.publicKey = p.getPublic().getEncoded(); return pair; } catch (GeneralSecurityException e) { throw new RuntimeException(e); } } public static byte[] encrypt(byte[] data, byte[] publicKey) { X509EncodedKeySpec publicKeySpec = new X509EncodedKeySpec(publicKey); try { KeyFactory kf = KeyFactory.getInstance("RSA"); PublicKey pk = kf.generatePublic(publicKeySpec); Cipher rsa = Cipher.getInstance(TRANSFORMATION); rsa.init(Cipher.ENCRYPT_MODE, pk); return rsa.doFinal(data); } catch (GeneralSecurityException e) { throw new RuntimeException(e); } } public static byte[] decrypt(byte[] encryptedData, byte[] privateKey) { try { PKCS8EncodedKeySpec privSpec = new PKCS8EncodedKeySpec(privateKey); RSAPrivateKey pk = (RSAPrivateKey) KeyFactory.getInstance("RSA") .generatePrivate(privSpec); Cipher rsaCipher = Cipher.getInstance(TRANSFORMATION); rsaCipher.init(Cipher.DECRYPT_MODE, pk); return rsaCipher.doFinal(encryptedData); } catch (GeneralSecurityException e) { throw new RuntimeException(e); } } }