import io.jsonwebtoken.SignatureAlgorithm;
import io.jsonwebtoken.security.Keys;
import org.apache.commons.codec.binary.Hex;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import java.security.*;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.HashMap;
import java.util.Map;
/**
* @Description KeyPairSignUtil
* @Author dsf
* @Date 2020/12/19 12:13
* @Version V1.0
**/
public class KeyPairSignUtil {
/**
* 生成RSA公、私钥对
* */
public static Map<String, String> generateRSAKeyPair() throws Exception{
KeyPairGenerator keyPairGenerator = null;
try {
keyPairGenerator = KeyPairGenerator.getInstance("RSA");
} catch (NoSuchAlgorithmException e){
throw e ;
}
keyPairGenerator.initialize(512);
//秘钥对
KeyPair keyPair = keyPairGenerator.generateKeyPair();
//公钥
PublicKey publicKey = keyPair.getPublic();
//私钥
PrivateKey privateKey = keyPair.getPrivate();
String publicKeyStr = java.util.Base64.getEncoder().encodeToString(publicKey.getEncoded());
String privateKeyStr = java.util.Base64.getEncoder().encodeToString(privateKey.getEncoded());
Map<String, String> map = new HashMap();
map.put("PRIVATE_KEY", privateKeyStr);
map.put("PUBLIC_KEY", publicKeyStr);
return map;
}
/**
* 进行签名
* @param base64RsaPrivateKey 被进行BASE64编码的RAS算法生成的私钥
* @param data 要被签名的数据
* */
public static String generateRSASignature(String base64RsaPrivateKey,String data) throws Exception {
byte[] bytes = java.util.Base64.getDecoder().decode(base64RsaPrivateKey) ;
PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(bytes);
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
Signature signature = Signature.getInstance("MD5withRSA");
signature.initSign(privateKey);
signature.update(data.getBytes("UTF-8"));
//生成签名
byte[] result = signature.sign();
return Hex.encodeHexString(result) ;
}
/**
* 对签名进行验证
* @param base64RsaPublicKey 被进行BASE64编码的RAS算法生成的公钥
* @param hexSign 十六进制编码后的签名
* @param signData 被签名的数据
* */
public static boolean verify(String base64RsaPublicKey,String hexSign,String signData) throws Exception {
byte[] bytes = java.util.Base64.getDecoder().decode(base64RsaPublicKey) ;
X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(bytes);
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
Signature signature = Signature.getInstance("MD5withRSA");
signature.initVerify(publicKey);
signature.update(signData.getBytes("UTF-8"));
return signature.verify(Hex.decodeHex(hexSign)) ;
}
/**
* 创建经过BASE64编码后的秘钥
* */
public static String generateSecretKey(){
Key key = Keys.secretKeyFor(SignatureAlgorithm.HS256);
return java.util.Base64.getEncoder().encodeToString(key.getEncoded());
}
/**
* 根据BASE64编码后的秘钥创建SecretKey对象
* */
public static SecretKey newSecretKey (String base64SecretKey) {
byte[] encodedKey = java.util.Base64.getDecoder().decode(base64SecretKey);
return new SecretKeySpec(encodedKey, SignatureAlgorithm.HS256.getJcaName());
}
public static void main(String[] args) throws Exception {
Map<String, String> keyPairMap = generateRSAKeyPair() ;
String base64RsaPrivateKey = keyPairMap.get("PRIVATE_KEY") ;
String base64RsaPublicKey = keyPairMap.get("PUBLIC_KEY") ;
System.out.println(base64RsaPrivateKey);
System.out.println(base64RsaPublicKey);
String data = "这是一个神奇的2020年" ;
//签名结果
String hexSign = generateRSASignature(base64RsaPrivateKey,data) ;
System.out.println(hexSign);
//验证签名结果
boolean result = verify(base64RsaPublicKey,hexSign,data) ;
System.out.println(result);
String base64SecretKey = generateSecretKey() ;
System.out.println(base64SecretKey);
SecretKey secretKey = newSecretKey(base64SecretKey) ;
System.out.println(secretKey.toString());
}
}原文：https://blog.51cto.com/dengshuangfu/2567370