AES加密 RSA签名

public class Main {public static void main(String[] args) throws Exception {// 生成RSA密钥对KeyPairGenerator keyGen = KeyPairGenerator.getInstance("RSA");keyGen.initialize(1024);KeyPair keyPair = keyGen.generateKeyPair();PublicKey publicKey = keyPair.getPublic();PrivateKey privateKey = keyPair.getPrivate();// 将公钥和私钥转换为Base64编码的字符串String rsaPublicKeyStr = Base64.getEncoder().encodeToString(publicKey.getEncoded());String rsaPrivateKeyStr = Base64.getEncoder().encodeToString(privateKey.getEncoded());// 对称加密算法String algorithm = "AES";// AES密钥（长度通常为128、192或256位）KeyGenerator aesKeyFactor = KeyGenerator.getInstance(algorithm);aesKeyFactor.init(128); // 128-bit AES keybyte[] aesKey = aesKeyFactor.generateKey().getEncoded();
//        String key = "1234567812345678"; // 16字节*8 = 128位// 敏感信息String content = "{\"dog_name\":\"小.王\",\"dogGender\":\"male\"}";String timestamp = String.valueOf(System.currentTimeMillis());// 拼接时间戳content = timestamp + "|" + content;System.out.println("\n-----------发送方-----------\n");Cipher cipher = Cipher.getInstance("AES/GCM/NoPadding");SecretKeySpec keySpec = new SecretKeySpec(aesKey, algorithm);// 随机初始化向量iv，以实现相同content加密后的密文是不同的byte[] iv = new byte[12];SecureRandom random = new SecureRandom();random.nextBytes(iv);String ivStr = Base64.getEncoder().encodeToString(iv);GCMParameterSpec gcmSpec = new GCMParameterSpec(128, iv);// 加密模式cipher.init(Cipher.ENCRYPT_MODE, keySpec, gcmSpec);byte[] encryptBytes = cipher.doFinal(content.getBytes());String encryptText = Base64.getEncoder().encodeToString(encryptBytes);// RSA私钥签名PrivateKey rsaPrivateKey = recoverPrivateKey(rsaPrivateKeyStr);Signature signer = Signature.getInstance("SHA256withRSA");signer.initSign(rsaPrivateKey);// 获取SHA-256 MessageDigest实例MessageDigest digest = MessageDigest.getInstance("SHA-256");// 对密文进行哈希处理byte[] hashBytes = digest.digest(encryptText.getBytes());signer.update(hashBytes); // 对密文的哈希值进行签名（而非对密文本身签名），以此避免得到过长的签名结果byte[] signatureBytes = signer.sign();String signature = Base64.getEncoder().encodeToString(signatureBytes);// 输出结果System.out.println("Encrypted Text: " + encryptText);System.out.println("Signature: " + signature);System.out.println("ivStr: " + ivStr);System.out.println("\n-----------接收方-----------\n");// 验签PublicKey rsaPublicKey = recoverPublicKey(rsaPublicKeyStr);Signature verifier = Signature.getInstance("SHA256withRSA");verifier.initVerify(rsaPublicKey);verifier.update(hashBytes);boolean isCorrect = verifier.verify(Base64.getDecoder().decode(signature));if (isCorrect) {System.out.println("验签成功");} else {System.out.println("验签失败");}// 解密Cipher recieverCipher = Cipher.getInstance("AES/GCM/NoPadding");SecretKeySpec receiverSk = new SecretKeySpec(aesKey, algorithm);byte[] receiverIv = Base64.getDecoder().decode(ivStr);GCMParameterSpec gcm = new GCMParameterSpec(128, receiverIv);// 解密模式recieverCipher.init(Cipher.DECRYPT_MODE, receiverSk, gcm);// 先将加密后的字符串解码回字节数据byte[] decodedBytes = Base64.getDecoder().decode(encryptText);byte[] plainBytes = recieverCipher.doFinal(decodedBytes);String plainText = new String(plainBytes).split("\\|")[1]; // 原文System.out.println(plainText);}private static PublicKey recoverPublicKey(String key) throws Exception {byte[] keyBytes = Base64.getDecoder().decode(key);X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);KeyFactory keyFactory = KeyFactory.getInstance("RSA");return keyFactory.generatePublic(keySpec);}private static PrivateKey recoverPrivateKey(String key) throws Exception {byte[] keyBytes = Base64.getDecoder().decode(key);PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(keyBytes);KeyFactory keyFactory = KeyFactory.getInstance("RSA");return keyFactory.generatePrivate(keySpec);}
}