import org.apache.commons.codec.binary.Base64; import javax.crypto.Cipher; import java.security.*; import java.security.interfaces.RSAPrivateKey; import java.security.interfaces.RSAPublicKey; import java.security.spec.PKCS8EncodedKeySpec; import java.security.spec.X509EncodedKeySpec; /** * @from fhadmin.cn * @description Rsa 工具类,公钥私钥生成,加解密 * @date 2020-05-18 **/ public class RsaUtils { private static final String SRC = "123456"; public static void main(String[] args) throws Exception { System.out.println(" "); RsaKeyPair keyPair = generateKeyPair(); System.out.println("公钥:" + keyPair.getPublicKey()); System.out.println("私钥:" + keyPair.getPrivateKey()); System.out.println(" "); test1(keyPair); System.out.println(" "); test2(keyPair); System.out.println(" "); } /** * 公钥加密私钥解密 */ private static void test1(RsaKeyPair keyPair) throws Exception { System.out.println("***************** 公钥加密私钥解密开始 *****************"); String text1 = encryptByPublicKey(keyPair.getPublicKey(), RsaUtils.SRC); String text2 = decryptByPrivateKey(keyPair.getPrivateKey(), text1); System.out.println("加密前:" + RsaUtils.SRC); System.out.println("加密后:" + text1); System.out.println("解密后:" + text2); if (RsaUtils.SRC.equals(text2)) { System.out.println("解密字符串和原始字符串一致,解密成功"); } else { System.out.println("解密字符串和原始字符串不一致,解密失败"); } System.out.println("***************** 公钥加密私钥解密结束 *****************"); } /** * 私钥加密公钥解密 * @throws Exception / */ private static void test2(RsaKeyPair keyPair) throws Exception { System.out.println("***************** 私钥加密公钥解密开始 *****************"); String text1 = encryptByPrivateKey(keyPair.getPrivateKey(), RsaUtils.SRC); String text2 = decryptByPublicKey(keyPair.getPublicKey(), text1); System.out.println("加密前:" + RsaUtils.SRC); System.out.println("加密后:" + text1); System.out.println("解密后:" + text2); if (RsaUtils.SRC.equals(text2)) { System.out.println("解密字符串和原始字符串一致,解密成功"); } else { System.out.println("解密字符串和原始字符串不一致,解密失败"); } System.out.println("***************** 私钥加密公钥解密结束 *****************"); } /** * 公钥解密 * @from fhadmin.cn * @param publicKeyText 公钥 * @param text 待解密的信息 * @return / * @throws Exception / */ public static String decryptByPublicKey(String publicKeyText, String text) throws Exception { X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(Base64.decodeBase64(publicKeyText)); KeyFactory keyFactory = KeyFactory.getInstance("RSA"); PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec); Cipher cipher = Cipher.getInstance("RSA"); cipher.init(Cipher.DECRYPT_MODE, publicKey); byte[] result = cipher.doFinal(Base64.decodeBase64(text)); return new String(result); } /** * 私钥加密 * @from fhadmin.cn * @param privateKeyText 私钥 * @param text 待加密的信息 * @return / * @throws Exception / */ public static String encryptByPrivateKey(String privateKeyText, String text) throws Exception { PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(Base64.decodeBase64(privateKeyText)); KeyFactory keyFactory = KeyFactory.getInstance("RSA"); PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec); Cipher cipher = Cipher.getInstance("RSA"); cipher.init(Cipher.ENCRYPT_MODE, privateKey); byte[] result = cipher.doFinal(text.getBytes()); return Base64.encodeBase64String(result); } /** * 私钥解密 * @from fhadmin.cn * @param privateKeyText 私钥 * @param text 待解密的文本 * @return / * @throws Exception / */ public static String decryptByPrivateKey(String privateKeyText, String text) throws Exception { PKCS8EncodedKeySpec pkcs8EncodedKeySpec5 = new PKCS8EncodedKeySpec(Base64.decodeBase64(privateKeyText)); KeyFactory keyFactory = KeyFactory.getInstance("RSA"); PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec5); Cipher cipher = Cipher.getInstance("RSA"); cipher.init(Cipher.DECRYPT_MODE, privateKey); byte[] result = cipher.doFinal(Base64.decodeBase64(text)); return new String(result); } /** * 公钥加密 * @from fhadmin.cn * @param publicKeyText 公钥 * @param text 待加密的文本 * @return / */ public static String encryptByPublicKey(String publicKeyText, String text) throws Exception { X509EncodedKeySpec x509EncodedKeySpec2 = new X509EncodedKeySpec(Base64.decodeBase64(publicKeyText)); KeyFactory keyFactory = KeyFactory.getInstance("RSA"); PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec2); Cipher cipher = Cipher.getInstance("RSA"); cipher.init(Cipher.ENCRYPT_MODE, publicKey); byte[] result = cipher.doFinal(text.getBytes()); return Base64.encodeBase64String(result); } /** * 构建RSA密钥对 * @from fhadmin.cn * @return / * @throws NoSuchAlgorithmException / */ public static RsaKeyPair generateKeyPair() throws NoSuchAlgorithmException { KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA"); keyPairGenerator.initialize(1024); KeyPair keyPair = keyPairGenerator.generateKeyPair(); RSAPublicKey rsaPublicKey = (RSAPublicKey) keyPair.getPublic(); RSAPrivateKey rsaPrivateKey = (RSAPrivateKey) keyPair.getPrivate(); String publicKeyString = Base64.encodeBase64String(rsaPublicKey.getEncoded()); String privateKeyString = Base64.encodeBase64String(rsaPrivateKey.getEncoded()); return new RsaKeyPair(publicKeyString, privateKeyString); } /** * RSA密钥对对象 */ public static class RsaKeyPair { private final String publicKey; private final String privateKey; public RsaKeyPair(String publicKey, String privateKey) { this.publicKey = publicKey; this.privateKey = privateKey; } public String getPublicKey() { return publicKey; } public String getPrivateKey() { return privateKey; } } }