需要引入bouncycastle库的jar包
package test; import java.io.UnsupportedEncodingException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import java.security.SecureRandom;
import java.security.Security;
import java.util.Base64; import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.KeyGenerator;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.SecretKeySpec; public class Aes256Util {
private final static String PROVIDER_BC = "BC";
private final static String CHARSET = "UTF-8";
private final static String ALGORITHM = "AES/ECB/PKCS5Padding";
private final static String KEY_ALGORITHM = "AES"; /**
* 引入BC库
*/
static {
try {
Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
} catch (Exception e) {
e.printStackTrace();
}
} /**
* 初始化一个256位对称加密的秘钥
* @param keyStr 如果加密解密的方法直接用一个String.getByte()的话，那么这个key需要达到128/192/256 bits
* @return
*/
public static byte[] getRandomKey(String keyStr){
KeyGenerator keyGenerator = null;
SecureRandom secureRandom = null;
try {
keyGenerator = KeyGenerator.getInstance(KEY_ALGORITHM);
secureRandom = SecureRandom.getInstance("SHA1PRNG");
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
secureRandom.setSeed(keyStr.getBytes());
keyGenerator.init(256, secureRandom);
return keyGenerator.generateKey().getEncoded();
} /**
* 加密
* @param content 原明文串
* @param key 对称加密秘钥
* @return 最后对byte进行了base64encode
*/
public static String encrypt(String content, byte[] key){
String encryptStr = ""; try {
//密码器初始化
Cipher cipher = Cipher.getInstance(ALGORITHM, PROVIDER_BC);
SecretKeySpec secretKeySpec = new SecretKeySpec(key, KEY_ALGORITHM);
cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec);
byte[] encryptByte = cipher.doFinal(content.getBytes(CHARSET)); encryptStr = Base64.getEncoder().encodeToString(encryptByte); } catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (NoSuchProviderException e) {
e.printStackTrace();
} catch (NoSuchPaddingException e) {
e.printStackTrace();
} catch (InvalidKeyException e) {
e.printStackTrace();
} catch (IllegalBlockSizeException e) {
e.printStackTrace();
} catch (BadPaddingException e) {
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} return encryptStr;
} /**
* 解密
* @param contentByte 加密后的密文byte
* @param key
* @return
*/
public static String decrypt(byte[] contentByte, byte[] key){
String decryptStr = "";
//密码器初始化
try {
Cipher cipher = Cipher.getInstance(ALGORITHM, PROVIDER_BC);
SecretKeySpec secretKeySpec = new SecretKeySpec(key, KEY_ALGORITHM);
cipher.init(Cipher.DECRYPT_MODE, secretKeySpec);
byte[] encryptByte = cipher.doFinal(contentByte); decryptStr = new String(encryptByte, CHARSET); } catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (NoSuchProviderException e) {
e.printStackTrace();
} catch (NoSuchPaddingException e) {
e.printStackTrace();
} catch (InvalidKeyException e) {
e.printStackTrace();
} catch (IllegalBlockSizeException e) {
e.printStackTrace();
} catch (BadPaddingException e) {
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} return decryptStr;
} public static void main(String[] args) {
String keyStr = "1111111111111111111111111111111"; byte[] rkey = getRandomKey(keyStr); String a = encrypt("test", rkey); String b = decrypt(Base64.getDecoder().decode(a), rkey); System.out.println(a);
System.out.println(b);
}
}