这个版本绝对能用,本人亲测
注意:需要下载两个jar包
【commons-codec-1.11-bin.zip】下载地址如下:
http://commons.apache.org/proper/commons-codec/download_codec.cgi
【commons-io-2.6-bin.zip】下载地址如下:
http://commons.apache.org/proper/commons-io/download_io.cgi
java项目需要BuildPath进你的项目;
如果是web项目需要加入WEB-INF的lib目录中刷新即可。
源码如下:
import org.apache.commons.codec.binary.Base64;
import org.apache.commons.io.IOUtils;
import javax.crypto.Cipher;
import java.io.ByteArrayOutputStream;
import java.security.*;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.HashMap;
import java.util.Map;
public class RSAUtil {
public static final String CHARSET = "UTF-8";
public static final String RSA_ALGORITHM = "RSA";
private static final String PUBLIC_KEY = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC/OpVr+aQu6B3stSUgsLcZWpaxatset8zTqat1FF543hoECcTnRqDXKwfX09J+RLCc/1fbITt0s4wUUwJNU7lKJSTGZp5/xHcEiFJjTa+XY6pQHQKvvZjAQMkyzC3H5tmaNTapKYJOAWw7u1dxcRNFdD3k5E+EiqSnlo30u7SLCwIDAQAB";
private static final String PRIVATE_KEY = "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";
public static void main (String[] args){
try {
// 如果你想使用不固定的秘钥可以打开下面三行
// Map<String, String> keyMap = RSAUtil.createKeys(1024);
// String publicKey = keyMap.get("publicKey");
// String privateKey = keyMap.get("privateKey");
System.out.println("公钥: \n\r" + PUBLIC_KEY);
System.out.println("私钥: \n\r" + PRIVATE_KEY);
System.out.println("公钥加密——私钥解密");
String str = "站在大明门前守卫的禁卫军,事先没有接到\n" +
"有关的命令,但看到大批盛装的官员来临,也就\n" +
"以为确系举行大典,因而未加询问。进大明门即\n" +
"为皇城。文武百官看到端门午门之前气氛平静,\n" +
"城楼上下也无朝会的迹象,既无几案,站队点名\n" +
"的御史和御前侍卫“大汉将军”也不见踪影,不免\n" +
"心中揣测,互相询问:所谓午朝是否讹传?";
System.out.println("\r明文:\r\n" + str);
System.out.println("\r明文大小:\r\n" + str.getBytes().length);
String encodedData = RSAUtil.privateEncrypt(str);
System.out.println("密文:\r\n" + encodedData);
String decodedData = RSAUtil.publicDecrypt(encodedData);
System.out.println("解密后文字: \r\n" + decodedData);
} catch (Exception e) {
// TODO: handle exception
}
}
public static Map<String, String> createKeys(int keySize){
//为RSA算法创建一个KeyPairGenerator对象
KeyPairGenerator kpg;
try{
kpg = KeyPairGenerator.getInstance(RSA_ALGORITHM);
}catch(NoSuchAlgorithmException e){
throw new IllegalArgumentException("No such algorithm-->[" + RSA_ALGORITHM + "]");
}
//初始化KeyPairGenerator对象,密钥长度
kpg.initialize(keySize);
//生成密匙对
KeyPair keyPair = kpg.generateKeyPair();
//得到公钥
Key publicKey = keyPair.getPublic();
String publicKeyStr = Base64.encodeBase64URLSafeString(publicKey.getEncoded());
//得到私钥
Key privateKey = keyPair.getPrivate();
String privateKeyStr = Base64.encodeBase64URLSafeString(privateKey.getEncoded());
Map<String, String> keyPairMap = new HashMap<String, String>();
keyPairMap.put("publicKey", publicKeyStr);
keyPairMap.put("privateKey", privateKeyStr);
return keyPairMap;
}
/**
* 得到公钥
* @param publicKey 密钥字符串(经过base64编码)
* @throws Exception
*/
public static RSAPublicKey getPublicKey(String publicKey) throws NoSuchAlgorithmException, InvalidKeySpecException {
//通过X509编码的Key指令获得公钥对象
KeyFactory keyFactory = KeyFactory.getInstance(RSA_ALGORITHM);
X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(Base64.decodeBase64(publicKey));
RSAPublicKey key = (RSAPublicKey) keyFactory.generatePublic(x509KeySpec);
return key;
}
/**
* 得到私钥
* @param privateKey 密钥字符串(经过base64编码)
* @throws Exception
*/
public static RSAPrivateKey getPrivateKey(String privateKey) throws NoSuchAlgorithmException, InvalidKeySpecException {
//通过PKCS#8编码的Key指令获得私钥对象
KeyFactory keyFactory = KeyFactory.getInstance(RSA_ALGORITHM);
PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(Base64.decodeBase64(privateKey));
RSAPrivateKey key = (RSAPrivateKey) keyFactory.generatePrivate(pkcs8KeySpec);
return key;
}
/**
* 公钥加密
* @param data
* @param publicKey
* @return
*/
public static String publicEncrypt(String data){
try{
RSAPublicKey publicKey = RSAUtil.getPublicKey(PUBLIC_KEY);
Cipher cipher = Cipher.getInstance(RSA_ALGORITHM);
cipher.init(Cipher.ENCRYPT_MODE, publicKey);
return Base64.encodeBase64URLSafeString(rsaSplitCodec(cipher, Cipher.ENCRYPT_MODE, data.getBytes(CHARSET), publicKey.getModulus().bitLength()));
}catch(Exception e){
throw new RuntimeException("加密字符串[" + data + "]时遇到异常", e);
}
}
/**
* 私钥解密
* @param data
* @param privateKey
* @return
*/
public static String privateDecrypt(String data){
try{
RSAPrivateKey privateKey = RSAUtil.getPrivateKey(PRIVATE_KEY);
Cipher cipher = Cipher.getInstance(RSA_ALGORITHM);
cipher.init(Cipher.DECRYPT_MODE, privateKey);
return new String(rsaSplitCodec(cipher, Cipher.DECRYPT_MODE, Base64.decodeBase64(data), privateKey.getModulus().bitLength()), CHARSET);
}catch(Exception e){
throw new RuntimeException("解密字符串[" + data + "]时遇到异常", e);
}
}
/**
* 私钥加密
* @param data
* @param privateKey
* @return
*/
public static String privateEncrypt(String data){
try{
RSAPrivateKey privateKey = RSAUtil.getPrivateKey(PRIVATE_KEY);
Cipher cipher = Cipher.getInstance(RSA_ALGORITHM);
cipher.init(Cipher.ENCRYPT_MODE, privateKey);
return Base64.encodeBase64URLSafeString(rsaSplitCodec(cipher, Cipher.ENCRYPT_MODE, data.getBytes(CHARSET), privateKey.getModulus().bitLength()));
}catch(Exception e){
throw new RuntimeException("加密字符串[" + data + "]时遇到异常", e);
}
}
/**
* 公钥解密
* @param data
* @param publicKey
* @return
*/
public static String publicDecrypt(String data){
try{
RSAPublicKey publicKey = RSAUtil.getPublicKey(PUBLIC_KEY);
Cipher cipher = Cipher.getInstance(RSA_ALGORITHM);
cipher.init(Cipher.DECRYPT_MODE, publicKey);
return new String(rsaSplitCodec(cipher, Cipher.DECRYPT_MODE, Base64.decodeBase64(data), publicKey.getModulus().bitLength()), CHARSET);
}catch(Exception e){
throw new RuntimeException("解密字符串[" + data + "]时遇到异常", e);
}
}
private static byte[] rsaSplitCodec(Cipher cipher, int opmode, byte[] datas, int keySize){
int maxBlock = 0;
if(opmode == Cipher.DECRYPT_MODE){
maxBlock = keySize / 8;
}else{
maxBlock = keySize / 8 - 11;
}
ByteArrayOutputStream out = new ByteArrayOutputStream();
int offSet = 0;
byte[] buff;
int i = 0;
try{
while(datas.length > offSet){
if(datas.length-offSet > maxBlock){
buff = cipher.doFinal(datas, offSet, maxBlock);
}else{
buff = cipher.doFinal(datas, offSet, datas.length-offSet);
}
out.write(buff, 0, buff.length);
i++;
offSet = i * maxBlock;
}
}catch(Exception e){
throw new RuntimeException("加解密阀值为["+maxBlock+"]的数据时发生异常", e);
}
byte[] resultDatas = out.toByteArray();
IOUtils.closeQuietly(out);
return resultDatas;
}
}