RAS非对称加密
加解密密钥不一致，一般私钥不公开，使用公钥加密，私钥解密，使用私钥加密，公钥可以解密。
java代码
import javax.crypto.Cipher; import java.security.*; import java.security.spec.PKCS8EncodedKeySpec; import java.security.spec.X509EncodedKeySpec; import java.util.Base64; public class RSA { //非对称密钥算法 private static final String KEY_ALGORITHM = "RSA"; //密钥长度，在512到65536位之间，建议不要太长，否则速度很慢，生成的加密数据很长 private static final int KEY_SIZE = 512; //字符编码 private static final String CHARSET = "UTF-8"; /** * 生成密钥对 * * @return KeyPair 密钥对 */ public static KeyPair getKeyPair() throws Exception { return getKeyPair(null); } /** * 生成密钥对 * @param password 生成密钥对的密码 * @return * @throws Exception */ public static KeyPair getKeyPair(String password) throws Exception { //实例化密钥生成器 KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance(KEY_ALGORITHM); //初始化密钥生成器 if(password == null){ keyPairGenerator.initialize(KEY_SIZE); }else { SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG"); secureRandom.setSeed(password.getBytes(CHARSET)); keyPairGenerator.initialize(KEY_SIZE, secureRandom); } //生成密钥对 return keyPairGenerator.generateKeyPair(); } /** * 取得私钥 * * @param keyPair 密钥对 * @return byte[] 私钥 */ public static byte[] getPrivateKeyBytes(KeyPair keyPair) { return keyPair.getPrivate().getEncoded(); } /** * 取得Base64编码的私钥 * * @param keyPair 密钥对 * @return String Base64编码的私钥 */ public static String getPrivateKey(KeyPair keyPair) { return Base64.getEncoder().encodeToString(getPrivateKeyBytes(keyPair)); } /** * 取得公钥 * * @param keyPair 密钥对 * @return byte[] 公钥 */ public static byte[] getPublicKeyBytes(KeyPair keyPair) { return keyPair.getPublic().getEncoded(); } /** * 取得Base64编码的公钥 * * @param keyPair 密钥对 * @return String Base64编码的公钥 */ public static String getPublicKey(KeyPair keyPair) { return Base64.getEncoder().encodeToString(getPublicKeyBytes(keyPair)); } /** * 私钥加密 * * @param data 待加密数据 * @param privateKey 私钥字节数组 * @return byte[] 加密数据 */ public static byte[] encryptByPrivateKey(byte[] data, byte[] privateKey) throws Exception { //实例化密钥工厂 KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM); //生成私钥 PrivateKey key = keyFactory.generatePrivate(new PKCS8EncodedKeySpec(privateKey)); //数据加密 Cipher cipher = Cipher.getInstance(KEY_ALGORITHM); cipher.init(Cipher.ENCRYPT_MODE, key); return cipher.doFinal(data); } /** * 私钥加密 * * @param data 待加密数据 * @param privateKey Base64编码的私钥 * @return String Base64编码的加密数据 */ public static String encryptByPrivateKey(String data, String privateKey) throws Exception { byte[] key = Base64.getDecoder().decode(privateKey); return Base64.getEncoder().encodeToString(encryptByPrivateKey(data.getBytes(CHARSET), key)); } /** * 公钥加密 * * @param data 待加密数据 * @param publicKey 公钥字节数组 * @return byte[] 加密数据 */ public static byte[] encryptByPublicKey(byte[] data, byte[] publicKey) throws Exception { //实例化密钥工厂 KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM); //生成公钥 PublicKey key = keyFactory.generatePublic(new X509EncodedKeySpec(publicKey)); //数据加密 Cipher cipher = Cipher.getInstance(KEY_ALGORITHM); cipher.init(Cipher.ENCRYPT_MODE, key); return cipher.doFinal(data); } /** * 公钥加密 * * @param data 待加密数据 * @param publicKey Base64编码的公钥 * @return String Base64编码的加密数据 */ public static String encryptByPublicKey(String data, String publicKey) throws Exception { byte[] key = Base64.getDecoder().decode(publicKey); return Base64.getEncoder().encodeToString(encryptByPublicKey(data.getBytes(CHARSET), key)); } /** * 私钥解密 * * @param data 待解密数据 * @param privateKey 私钥字节数组 * @return byte[] 解密数据 */ public static byte[] decryptByPrivateKey(byte[] data, byte[] privateKey) throws Exception { //实例化密钥工厂 KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM); //生成私钥 PrivateKey key = keyFactory.generatePrivate(new PKCS8EncodedKeySpec(privateKey)); //数据解密 Cipher cipher = Cipher.getInstance(KEY_ALGORITHM); cipher.init(Cipher.DECRYPT_MODE, key); return cipher.doFinal(data); } /** * 私钥解密 * * @param data Base64编码的待解密数据 * @param privateKey Base64编码的私钥 * @return String 解密数据 */ public static String decryptByPrivateKey(String data, String privateKey) throws Exception { byte[] key = Base64.getDecoder().decode(privateKey); return new String(decryptByPrivateKey(Base64.getDecoder().decode(data), key), CHARSET); } /** * 公钥解密 * * @param data 待解密数据 * @param publicKey 公钥字节数组 * @return byte[] 解密数据 */ public static byte[] decryptByPublicKey(byte[] data, byte[] publicKey) throws Exception { //实例化密钥工厂 KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM); //产生公钥 PublicKey key = keyFactory.generatePublic(new X509EncodedKeySpec(publicKey)); //数据解密 Cipher cipher = Cipher.getInstance(KEY_ALGORITHM); cipher.init(Cipher.DECRYPT_MODE, key); return cipher.doFinal(data); } /** * 公钥解密 * * @param data Base64编码的待解密数据 * @param publicKey Base64编码的公钥 * @return String 解密数据 */ public static String decryptByPublicKey(String data, String publicKey) throws Exception { byte[] key = Base64.getDecoder().decode(publicKey); return new String(decryptByPublicKey(Base64.getDecoder().decode(data), key), CHARSET); } /** * 测试加解密方法 * * @param args * @throws Exception */ public static void main(String[] args) throws Exception { //生成密钥对，一般生成之后可以放到配置文件中 KeyPair keyPair = RSA.getKeyPair(); //公钥 String publicKey = RSA.getPublicKey(keyPair); //私钥 String privateKey = RSA.getPrivateKey(keyPair); System.out.println("公钥：\n" + publicKey); System.out.println("私钥：\n" + privateKey); String data = "RSA 加密解密测试!"; { System.out.println("\n===========私钥加密，公钥解密=============="); String s1 = RSA.encryptByPrivateKey(data, privateKey); System.out.println("加密后的数据:" + s1); String s2 = RSA.decryptByPublicKey(s1, publicKey); System.out.println("解密后的数据:" + s2 + "\n\n"); } { System.out.println("\n===========公钥加密，私钥解密=============="); String s1 = RSA.encryptByPublicKey(data, publicKey); System.out.println("加密后的数据:" + s1); String s2 = RSA.decryptByPrivateKey(s1, privateKey); System.out.println("解密后的数据:" + s2 + "\n\n"); } } }
js代码 依赖 jsencrypt 项目
<script src="bin/jsencrypt.min.js"></script>
<script type="text/javascript">
var encrypt = new JSEncrypt();
encrypt.setPublicKey('java生成的公钥');//后台给
var encrypted = encrypt.encrypt('加密的字符串');
</script>
