RSA加解密java中的使用

• 使用环境：eclipse + maven，无maven猿友可自行下载这两个jar包：bcprov-jdk16-1.4.5.jar 和 commons-codec-1.6.jar
• maven的猿友添加如下依赖：

<dependency>
    <groupId>org.bouncycastle</groupId>
    <artifactId>bcprov-jdk16</artifactId>
    <version>1.45</version>
</dependency>
<dependency>
    <groupId>commons-codec</groupId>
    <artifactId>commons-codec</artifactId>
    <version>1.6</version>
</dependency>

• 目录结构，包含三个类。

  
  

• 生成密钥，公钥和私钥

package com.luo.util;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.SecureRandom;
import java.security.Security;
import org.apache.commons.codec.binary.Base64;
public class RSAKeyCreater
public class RSAKeyCreater {

    public static void createKeyPairs() {
        try {
            Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
            KeyPairGenerator generator = KeyPairGenerator.getInstance("RSA", "BC");
            generator.initialize(512, new SecureRandom());
            KeyPair pair = generator.generateKeyPair();
            PublicKey pubKey = pair.getPublic();
            PrivateKey privKey = pair.getPrivate();
            byte[] pk = pubKey.getEncoded();
            byte[] privk = privKey.getEncoded();
            String strpk = new String(Base64.encodeBase64(pk));
            String strprivk = new String(Base64.encodeBase64(privk));

            System.out.println("公钥Base64编码:" + strpk);
            System.out.println("私钥Base64编码:" + strprivk);
        } catch (Exception e) {
            e.printStackTrace();
        }

    }
    public static void main(String args[]){
            creatkeyPairs()
    } 
}

• 运行该类main方法控制台输入如下，获得公钥和私钥，公钥用于加密，私钥用于解密：

  
  

• RSA加密解密类

  • RsaUtil.java内容如下：

package com.luo.util;
import java.security.PrivateKey;
import java.security.PublicKey;
import javax.crypto.Cipher;
import org.apache.commons.codec.binary.Base64;
public class RsaUtil {

    /**
     * luoguohui
     * 2015-12-26
     * RSA加密
     */
        public String encryptData(String data, PublicKey publicKey) {
            try {
                Cipher cipher = Cipher.getInstance("RSA");
                cipher.init(Cipher.ENCRYPT_MODE, publicKey);
                byte[] dataToEncrypt = data.getBytes("utf-8");
                byte[] encryptedData = cipher.doFinal(dataToEncrypt);
                String encryptString = Base64.encodeBase64String(encryptedData);
                return encryptString;
            } catch (Exception e) {
                e.printStackTrace();
            }
            return null;
        }
        /**
         * luoguohui
         * 2015-12-26
         * RSA解密
         */
        public String decryptData(String data, PrivateKey privateKey) {
            try {
                Cipher cipher = Cipher.getInstance("RSA");
                cipher.init(Cipher.DECRYPT_MODE, privateKey);
                byte[] descryptData = Base64.decodeBase64(data);
                byte[] descryptedData = cipher.doFinal(descryptData);
                String srcData = new String(descryptedData, "utf-8");
                return srcData;
            } catch (Exception e) {
                e.printStackTrace();
            }
            return null;
         }
}

• 加密解密测试
  • RSATest.java内容如下：

package com.luo.util;
import java.security.KeyFactory;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.Security;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import org.apache.commons.codec.binary.Base64;
public class RSATest {

        public static void testRsa() {
            try {
                Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());

                String strpk = "MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBAJPSsAm9Po08VtGKQx86TuOYu/7BTOtwYlFQvjQCEs3aTeUOH3p9pgd3pw14Num0n/l3Sk3d1av4hzZJvlODfScCAwEAAQ==";
                String strprivk = "MIIBVAIBADANBgkqhkiG9w0BAQEFAASCAT4wggE6AgEAAkEAk9KwCb0+jTxW0YpDHzpO45i7/sFM63BiUVC+NAISzdpN5Q4fen2mB3enDXg26bSf+XdKTd3Vq/iHNkm+U4N9JwIDAQABAkAch9iUOKNfDRtQnBfyagWZ5fu64sIe2vUO7r+XOCM6+a/BvKV+5aMRpR6ts8OyEz9F+KCagc8eSEO0DAFjurQ5AiEA72jh09XwAHpvUONQu8JyziZtB5Cpf/y2iCC3ucxJ510CIQCeEQ+2sd4jC7P+wdCB0K1HxXtslxD3Bq50yVtsyI3CUwIhAJUpQ4o4QNALeE9tUV+qRt0qE8Qi3Xhge1lVCSM5pNIBAiACY0OXgOxYHy8i5A6gR2S2ttb8dvO8p48vGHOXGxh5HQIgfiKMcSTfflaQBBgzDFvaVnsfs2ajbv9tNcWuAP7u6aA=";

                X509EncodedKeySpec pubX509 = new X509EncodedKeySpec(Base64.decodeBase64(strpk.getBytes()));
                PKCS8EncodedKeySpec priPKCS8 = new PKCS8EncodedKeySpec(Base64.decodeBase64(strprivk.getBytes()));

                KeyFactory keyf = KeyFactory.getInstance("RSA", "BC");
                PublicKey pubKey = keyf.generatePublic(pubX509);
                PrivateKey privKey = keyf.generatePrivate(priPKCS8);

                RsaUtil rsaUtil =  new RsaUtil();
                String data = "luoguohui";
                System.out.println("加密前字符串：data=" + data);
                String encryptData = null;
                if (pubKey != null && (data != null && !data.equals(""))) {
                    encryptData = rsaUtil.encryptData(data, pubKey);
                    System.out.println("加密后字符串：encryptData=" + encryptData);
                }
                String descryptData = null;
                if (privKey != null && (encryptData != null && !encryptData.equals(""))) {
                    descryptData = rsaUtil.decryptData(encryptData, privKey);
                    System.out.println("解密后字符串：descryptData=" + descryptData);
                } 
             }catch (Exception e) {
                e.printStackTrace();
            }
      }
      public static void main(String args[]) {
          testRsa();
      }
}

• 其中strpk和strprivk是2.1中运行获得公钥私钥串

• 运行RSATest.java的main方法，得到运行结果如下：

  
  

源码地址