JAVA实现RSA非对称性密码加密与解密

创建RSAKeyMap.java类

packagetest_time;

importjava.security.Key;

importjava.security.KeyPair;

importjava.security.KeyPairGenerator;

importjava.security.interfaces.RSAPrivateKey;

importjava.security.interfaces.RSAPublicKey;

importjava.util.HashMap;

importjava.util.Map;

import sun.misc.BASE64Decoder;

import sun.misc.BASE64Encoder;

@SuppressWarnings("unused")

public class RSAKeyMap {

public static final String KEY_ALGORITHM = "RSA";

public static final String SIGNATURE_ALGORITHM = "MD5withRSA";

private static final String PUBLIC_KEY = "RSAPublicKey";

private static final String PRIVATE_KEY = "RSAPrivateKey";

public static String getPublicKey(MapkeyMap) throws Exception { Key key = (Key) keyMap.get(PUBLIC_KEY);

byte[] publicKey = key.getEncoded();

return encryptBASE64(key.getEncoded());

}

public static String getPrivateKey(MapkeyMap) throws Exception { Key key = (Key) keyMap.get(PRIVATE_KEY);

byte[] privateKey =key.getEncoded();

return encryptBASE64(key.getEncoded());

}

public static byte[] decryptBASE64(String key) throws Exception {

return (new BASE64Decoder()).decodeBuffer(key);

}

public static String encryptBASE64(byte[] key) throws Exception {

return (new BASE64Encoder()).encodeBuffer(key);

}

public static MapinitKey() throws Exception { KeyPairGeneratorkeyPairGen = KeyPairGenerator.getInstance(KEY_ALGORITHM); keyPairGen.initialize(1024);

KeyPairkeyPair = keyPairGen.generateKeyPair();

RSAPublicKeypublicKey = (RSAPublicKey) keyPair.getPublic(); RSAPrivateKeyprivateKey = (RSAPrivateKey) keyPair.getPrivate();

MapkeyMap = new HashMap(2);

keyMap.put(PUBLIC_KEY, publicKey); keyMap.put(PRIVATE_KEY, privateKey); returnkeyMap;

}/*

public static void main(String[] args) {

MapkeyMap;

try {

keyMap = initKey();

String publicKey= getPublicKey(keyMap); System.out.println(publicKey);

String privateKey= getPrivateKey(keyMap); System.out.println(privateKey);

} catch (Exception e) {

e.printStackTrace();

}

}

*/

}

测试截图

将main方法注释掉

创建RSA.java类

packagetest_time;

importjava.io.UnsupportedEncodingException; importjava.security.InvalidKeyException; importjava.security.KeyFactory;

importjava.security.MessageDigest; importjava.security.NoSuchAlgorithmException; importjava.security.PrivateKey;

importjava.security.PublicKey;

importjava.security.SecureRandom;

import java.security.spec.PKCS8EncodedKeySpec;

import java.security.spec.X509EncodedKeySpec; importjava.util.Map;

importjavax.crypto.BadPaddingException; importjavax.crypto.Cipher;

importjavax.crypto.IllegalBlockSizeException; importjavax.crypto.KeyGenerator;

importjavax.crypto.NoSuchPaddingException; importjavax.crypto.SecretKey;

import com.sun.mail.util.BASE64DecoderStream;

import com.sun.mail.util.BASE64EncoderStream;

import sun.misc.BASE64Decoder;

public class RSA {

/**

* 传入名文和公钥钥对数据进行RSA解密

*
返回值：String

*
@paramsrc

*
@parampubkey

*
@return

*/

public static String rsaEncoding(String src,PublicKeypubkey){ try {

Cipher cip = Cipher.getInstance("RSA"); cip.init(cip.ENCRYPT_MODE, pubkey);

byte[] by = cip.doFinal(src.getBytes());

return new String(BASE64EncoderStream.encode(by));

} catch (NoSuchAlgorithmException e) {

throw new RuntimeException(e);

} catch (NoSuchPaddingException e) {

throw new RuntimeException(e);

} catch (InvalidKeyException e) {

throw new RuntimeException(e);

} catch (IllegalBlockSizeException e) {

throw new RuntimeException(e);

} catch (BadPaddingException e) {

throw new RuntimeException(e);

}

}

/**

* 传入RSA密文和私钥对数据进行解密

*
返回值：String

*
@param sec

*
@paramprivkey

*
@return

*/

public static String rsaDeEncoding(String sec,PrivateKeyprivkey){

try {

Cipher cip = Cipher.getInstance("RSA");

cip.init(cip.DECRYPT_MODE, privkey);

byte[] by = BASE64DecoderStream.decode(sec.getBytes());

return new String(cip.doFinal(by));

} catch (NoSuchAlgorithmException e) {

throw new RuntimeException(e);

} catch (NoSuchPaddingException e) {

throw new RuntimeException(e);

} catch (InvalidKeyException e) {

throw new RuntimeException(e);

} catch (IllegalBlockSizeException e) {

throw new RuntimeException(e);

} catch (BadPaddingException e) {

throw new RuntimeException(e);

}

}

/**

* 将String类型公钥转换成PublicKey类型

* @param key

* @return

* @throws Exception

*/

public static PublicKeygetPublicKey(String key) throws Exception {

byte[] keyBytes;

keyBytes = (new BASE64Decoder()).decodeBuffer(key);

X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes); KeyFactorykeyFactory = KeyFactory.getInstance("RSA"); PublicKeypublicKey = keyFactory.generatePublic(keySpec); returnpublicKey;

}

/**

* 将String类型私钥转换成PrivateKey类型

* @param key

* @return

* @throws Exception

*/

public static PrivateKeygetPrivateKey(String key) throws Exception {

byte[] keyBytes;

keyBytes = (new BASE64Decoder()).decodeBuffer(key);

PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(keyBytes); KeyFactorykeyFactory = KeyFactory.getInstance("RSA"); PrivateKeyprivateKey = keyFactory.generatePrivate(keySpec); returnprivateKey;

}

}

需要在lib包里面导入m ai l.j ar

包

测试：

publicstaticvoid main(String[] args) {

RSAKeyMap rsa=new RSAKeyMap();

MapkeyMap;

String password="董迎顺123456";

System.out.println("即将加密的密码为："+password);

try {

keyMap = rsa.initKey();

String publicKey= rsa.getPublicKey(keyMap);

System.out.println("分配的公钥为:"+publicKey);

String privateKey = rsa. getPrivateKey(keyMap);

System.out.println("分配的私钥为:"+privateKey);

//传入名文和公钥钥对数据进行RSA加密

String rsaPub=rsaEncoding(password, getPublicKey(publicKey));

System.out.println("加密后的密码为："+rsaPub);

//传入RSA密文和私钥对数据进行解密

String password1=rsaDeEncoding(rsaPub,getPrivateKey(privateKey));

System.out.println("解密后密码为"+password1);

} catch (Exception e) {

e.printStackTrace();

}