JAVA中的RSA密钥生成及签名验签_sign.initsign

RSA密钥生成

生成一个别名为test的私钥和证书，需要按提示输入私钥密码和证书信息，

keytool -genkey -keystore test.p12 -alias test -keyalg RSA -keysize 1024 -storetype pkcs12

导出公钥证书

keytool -export -alias test -keystore test.p12 -file test.crt

@Component
public class RSAEncrypt {
 
	private static Logger logger = LoggerFactory.getLogger(RSAEncrypt.class);
	private static RSAEncrypt rsaEncrypt;
 
	@PostConstruct
	private void initPro() throws Exception {
		rsaEncrypt = this;
		rsaEncrypt.hbpayConfig = this.hbpayConfig;
		RSAEncrypt.init();
	}
 
	/**
	 * 初始化证书
	 * @throws Exception 
	 */
	private static void init() throws Exception {
		getPrivateKey();
		getPublicKey();
	}
 
	@Autowired
	private HBpayConfig hbpayConfig;
 
	private static PrivateKey privateKey;
 
	private static PublicKey publicKey;
 
	// 从keystore文件中提取私钥 filename:D:\certs\test.p12
	private static PrivateKey getPrivateKey() {
		if(rsaEncrypt.privateKey == null){
			BufferedInputStream bufferedInputStream = null;
			try {
				FileInputStream is = new FileInputStream(rsaEncrypt.hbpayConfig.getPrivateKeyPath());
				bufferedInputStream = new BufferedInputStream(is);
				KeyStore keystore = KeyStore.getInstance(KeyStore.getDefaultType());
				char[] passwd = rsaEncrypt.hbpayConfig.getPrivateKeyPwd().toCharArray();
				keystore.load(bufferedInputStream, passwd);
				rsaEncrypt.privateKey = (PrivateKey) keystore.getKey(rsaEncrypt.hbpayConfig.getPrivateKeyAlias(), passwd);
				return rsaEncrypt.privateKey;
			} catch (KeyStoreException e) {
				e.printStackTrace();
			} catch (IOException e) {
				e.printStackTrace();
			} catch (NoSuchAlgorithmException e) {
				e.printStackTrace();
			} catch (CertificateException e) {
				e.printStackTrace();
			} catch (UnrecoverableKeyException e) {
				e.printStackTrace();
			} finally {
 
				try {
					if(bufferedInputStream != null){
						bufferedInputStream.close();
					}
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return null;
		}else{
			return rsaEncrypt.privateKey;
		}
 
	}
 
	// 签名
	private static String sign(PrivateKey privateKey, String message) throws Exception {
		Signature sign = Signature.getInstance("SHA1withRSA");
		sign.initSign(privateKey);
		sign.update(message.getBytes("UTF-8"));
		return new String(Base64.getEncoder().encodeToString(sign.sign()));
	}
 
	// 验签 读取公钥 ,公钥和包提供filename:D:\certs\test.crt
	private static PublicKey getPublicKey() throws Exception {
		if(rsaEncrypt.publicKey == null){
			BufferedInputStream bufferedInputStream = null;
			try {
				CertificateFactory cf = CertificateFactory.getInstance("X.509");
				FileInputStream inStream = new FileInputStream(rsaEncrypt.hbpayConfig.getPublicKeyPath());
				bufferedInputStream = new BufferedInputStream(inStream);
				Certificate cert = cf.generateCertificate(bufferedInputStream);
				rsaEncrypt.publicKey = cert.getPublicKey();
				return rsaEncrypt.publicKey;
			} catch (CertificateException e) {
				e.printStackTrace();
			} catch (FileNotFoundException e) {
				e.printStackTrace();
			} finally {
				try {
					if(bufferedInputStream != null){
						bufferedInputStream.close();
					}
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return null;
		}
		return rsaEncrypt.publicKey;
	}
 
	// 验签
	public static boolean verify(String message, String signature) throws Exception {
		Signature sign = Signature.getInstance("SHA1withRSA");
		sign.initVerify(rsaEncrypt.publicKey);
		sign.update(message.getBytes("UTF-8"));
		return sign.verify(Base64.getDecoder().decode(signature));
	}
 
	// 请求报文 签名 message=body
	public static String getSign(String message) {
 
		logger.info("签名数据：{}",message);
		String sign = null;
		try {
			sign = sign(rsaEncrypt.privateKey, message);
		} catch (Exception e) {
			e.printStackTrace();
		}
		return sign;
	}
 
	// 请求报文 签名 map=body
	public String getSignByMap(LinkedHashMap<String, String> header, LinkedHashMap<String, String> body) {
		String sign = null;
		StringBuilder message = new StringBuilder();
		for (Map.Entry<String, String> entry : header.entrySet()) {
			String value = entry.getValue();
			message.append(value);
		}
		for (Map.Entry<String, String> entry : body.entrySet()) {
			String value = entry.getValue();
			message.append(value);
		}
		try {
			sign = sign(rsaEncrypt.privateKey, message.toString());
		} catch (Exception e) {
			e.printStackTrace();
		}
		return sign;
	}
}