- /**
- * AESHelper.java
- * cn.com.songjy.test
- *
- * Function: TODO
- *
- * ver date author
- * ──────────────────────────────────
- * 2012-6-29 songjianyong
- *
- * Copyright (c) 2012, TNT All Rights Reserved.
- */
- package cn.com.songjy.test;
- import java.io.UnsupportedEncodingException;
- import java.security.InvalidKeyException;
- import java.security.NoSuchAlgorithmException;
- import java.security.SecureRandom;
- import javax.crypto.BadPaddingException;
- import javax.crypto.Cipher;
- import javax.crypto.IllegalBlockSizeException;
- import javax.crypto.KeyGenerator;
- import javax.crypto.NoSuchPaddingException;
- import javax.crypto.SecretKey;
- import javax.crypto.spec.SecretKeySpec;
- /**
- * ClassName:AESHelper
- *
- * @author songjianyong
- * @version 1.0
- * @since v1.0
- * @Date 2012-6-29 下午2:06:07
- */
- public class AESHelper {
- /**
- * @method main
- * @param args
- * @throws
- * @since v1.0
- */
- public static void main(String[] args) {
- String content = "宋建勇";
- String password = "12345678";
- byte[] encryptResult = encrypt(content, password);//加密
- byte[] decryptResult = decrypt(encryptResult,password);//解密
- System.out.println("解密后:" + new String(decryptResult));
- /*容易出错的地方,请看下面代码*/
- System.out.println("***********************************************");
- try {
- String encryptResultStr = new String(encryptResult,"utf-8");
- decryptResult = decrypt(encryptResultStr.getBytes("utf-8"),password);
- System.out.println("解密后:" + new String(decryptResult));
- } catch (UnsupportedEncodingException e) {
- e.printStackTrace();
- } catch (Exception e) {
- // TODO: handle exception
- }
- /*则,系统会报出如下异常:javax.crypto.IllegalBlockSizeException: Input length must be multiple of 16 when decrypting with padded cipher
- at com.sun.crypto.provider.SunJCE_f.b(DashoA13*..)
- at com.sun.crypto.provider.SunJCE_f.b(DashoA13*..)
- at com.sun.crypto.provider.AESCipher.engineDoFinal(DashoA13*..)
- at javax.crypto.Cipher.doFinal(DashoA13*..)
- at cn.com.songjy.test.ASCHelper.decrypt(ASCHelper.java:131)
- at cn.com.songjy.test.ASCHelper.main(ASCHelper.java:58)
- * */
- /*这主要是因为加密后的byte数组是不能强制转换成字符串的, 换言之,字符串和byte数组在这种情况下不是互逆的,
- * 要避免这种情况,我们需要做一些修订,可以考虑将二进制数据转换成十六进制表示,
- * 主要有两个方法:将二进制转换成16进制(见方法parseByte2HexStr)或是将16进制转换为二进制(见方法parseHexStr2Byte)*/
- /*然后,我们再修订以上测试代码*/
- System.out.println("***********************************************");
- String encryptResultStr = parseByte2HexStr(encryptResult);
- System.out.println("加密后:" + encryptResultStr);
- byte[] decryptFrom = parseHexStr2Byte(encryptResultStr);
- decryptResult = decrypt(decryptFrom,password);//解码
- System.out.println("解密后:" + new String(decryptResult));
- }
- /**
- * 加密
- * @method encrypt
- * @param content 需要加密的内容
- * @param password 加密密码
- * @return
- * @throws
- * @since v1.0
- */
- public static byte[] encrypt(String content, String password){
- try {
- KeyGenerator kgen = KeyGenerator.getInstance("AES");
- kgen.init(128, new SecureRandom(password.getBytes()));
- SecretKey secretKey = kgen.generateKey();
- byte[] enCodeFormat = secretKey.getEncoded();
- SecretKeySpec key = new SecretKeySpec(enCodeFormat, "AES");
- Cipher cipher = Cipher.getInstance("AES");// 创建密码器
- byte[] byteContent = content.getBytes("utf-8");
- cipher.init(Cipher.ENCRYPT_MODE, key);// 初始化
- byte[] result = cipher.doFinal(byteContent);
- return result; // 加密
- } catch (NoSuchAlgorithmException e) {
- e.printStackTrace();
- }catch (NoSuchPaddingException e) {
- e.printStackTrace();
- }catch (UnsupportedEncodingException e) {
- e.printStackTrace();
- }catch (InvalidKeyException e) {
- e.printStackTrace();
- }catch (IllegalBlockSizeException e) {
- e.printStackTrace();
- }catch (BadPaddingException e) {
- e.printStackTrace();
- }
- return null;
- }
- /**
- * 解密
- * @method decrypt
- * @param content 待解密内容
- * @param password 解密密钥
- * @return
- * @throws
- * @since v1.0
- */
- public static byte[] decrypt(byte[] content, String password){
- try {
- KeyGenerator kgen = KeyGenerator.getInstance("AES");
- kgen.init(128, new SecureRandom(password.getBytes()));
- SecretKey secretKey = kgen.generateKey();
- byte[] enCodeFormat = secretKey.getEncoded();
- SecretKeySpec key = new SecretKeySpec(enCodeFormat, "AES");
- Cipher cipher = Cipher.getInstance("AES");// 创建密码器
- cipher.init(Cipher.DECRYPT_MODE, key);// 初始化
- byte[] result = cipher.doFinal(content);
- return result; // 解密
- } catch (NoSuchAlgorithmException e) {
- e.printStackTrace();
- }catch (NoSuchPaddingException e) {
- e.printStackTrace();
- }catch (InvalidKeyException e) {
- e.printStackTrace();
- }catch (IllegalBlockSizeException e) {
- e.printStackTrace();
- }catch (BadPaddingException e) {
- e.printStackTrace();
- }
- return null;
- }
- /**
- * 将二进制转换成16进制
- * @method parseByte2HexStr
- * @param buf
- * @return
- * @throws
- * @since v1.0
- */
- public static String parseByte2HexStr(byte buf[]){
- StringBuffer sb = new StringBuffer();
- for(int i = 0; i < buf.length; i++){
- String hex = Integer.toHexString(buf[i] & 0xFF);
- if (hex.length() == 1) {
- hex = '0' + hex;
- }
- sb.append(hex.toUpperCase());
- }
- return sb.toString();
- }
- /**
- * 将16进制转换为二进制
- * @method parseHexStr2Byte
- * @param hexStr
- * @return
- * @throws
- * @since v1.0
- */
- public static byte[] parseHexStr2Byte(String hexStr){
- if(hexStr.length() < 1)
- return null;
- byte[] result = new byte[hexStr.length()/2];
- for (int i = 0;i< hexStr.length()/2; i++) {
- int high = Integer.parseInt(hexStr.substring(i*2, i*2+1), 16);
- int low = Integer.parseInt(hexStr.substring(i*2+1, i*2+2), 16);
- result[i] = (byte) (high * 16 + low);
- }
- return result;
- }
- /**
- * 另外一种加密方式--这种加密方式有两种限制
- * 1、密钥必须是16位的
- * 2、待加密内容的长度必须是16的倍数,如果不是16的倍数,就会出如下异常
- * javax.crypto.IllegalBlockSizeException: Input length not multiple of 16 bytes
- at com.sun.crypto.provider.SunJCE_f.a(DashoA13*..)
- at com.sun.crypto.provider.SunJCE_f.b(DashoA13*..)
- at com.sun.crypto.provider.SunJCE_f.b(DashoA13*..)
- at com.sun.crypto.provider.AESCipher.engineDoFinal(DashoA13*..)
- at javax.crypto.Cipher.doFinal(DashoA13*..)
- 要解决如上异常,可以通过补全传入加密内容等方式进行避免。
- * @method encrypt2
- * @param content 需要加密的内容
- * @param password 加密密码
- * @return
- * @throws
- * @since v1.0
- */
- public static byte[] encrypt2(String content, String password){
- try {
- SecretKeySpec key = new SecretKeySpec(password.getBytes(), "AES");
- Cipher cipher = Cipher.getInstance("AES/ECB/NoPadding");
- byte[] byteContent = content.getBytes("utf-8");
- cipher.init(Cipher.ENCRYPT_MODE, key);// 初始化
- byte[] result = cipher.doFinal(byteContent);
- return result; // 加密
- } catch (NoSuchAlgorithmException e) {
- e.printStackTrace();
- } catch (NoSuchPaddingException e) {
- e.printStackTrace();
- } catch (UnsupportedEncodingException e) {
- e.printStackTrace();
- } catch (InvalidKeyException e) {
- e.printStackTrace();
- } catch (IllegalBlockSizeException e) {
- e.printStackTrace();
- } catch (BadPaddingException e) {
- e.printStackTrace();
- }
- return null;
- }
- }
/** * AESHelper.java * cn.com.songjy.test * * Function: TODO * * ver date author * ────────────────────────────────── * 2012-6-29 songjianyong * * Copyright (c) 2012, TNT All Rights Reserved. */ package cn.com.songjy.test; import java.io.UnsupportedEncodingException; import java.security.InvalidKeyException; import java.security.NoSuchAlgorithmException; import java.security.SecureRandom; import javax.crypto.BadPaddingException; import javax.crypto.Cipher; import javax.crypto.IllegalBlockSizeException; import javax.crypto.KeyGenerator; import javax.crypto.NoSuchPaddingException; import javax.crypto.SecretKey; import javax.crypto.spec.SecretKeySpec; /** * ClassName:AESHelper * * @author songjianyong * @version 1.0 * @since v1.0 * @Date 2012-6-29 下午2:06:07 */ public class AESHelper { /** * @method main * @param args * @throws * @since v1.0 */ public static void main(String[] args) { String content = "宋建勇"; String password = "12345678"; byte[] encryptResult = encrypt(content, password);//加密 byte[] decryptResult = decrypt(encryptResult,password);//解密 System.out.println("解密后:" + new String(decryptResult)); /*容易出错的地方,请看下面代码*/ System.out.println("***********************************************"); try { String encryptResultStr = new String(encryptResult,"utf-8"); decryptResult = decrypt(encryptResultStr.getBytes("utf-8"),password); System.out.println("解密后:" + new String(decryptResult)); } catch (UnsupportedEncodingException e) { e.printStackTrace(); } catch (Exception e) { // TODO: handle exception } /*则,系统会报出如下异常:javax.crypto.IllegalBlockSizeException: Input length must be multiple of 16 when decrypting with padded cipher at com.sun.crypto.provider.SunJCE_f.b(DashoA13*..) at com.sun.crypto.provider.SunJCE_f.b(DashoA13*..) at com.sun.crypto.provider.AESCipher.engineDoFinal(DashoA13*..) at javax.crypto.Cipher.doFinal(DashoA13*..) at cn.com.songjy.test.ASCHelper.decrypt(ASCHelper.java:131) at cn.com.songjy.test.ASCHelper.main(ASCHelper.java:58) * */ /*这主要是因为加密后的byte数组是不能强制转换成字符串的, 换言之,字符串和byte数组在这种情况下不是互逆的, * 要避免这种情况,我们需要做一些修订,可以考虑将二进制数据转换成十六进制表示, * 主要有两个方法:将二进制转换成16进制(见方法parseByte2HexStr)或是将16进制转换为二进制(见方法parseHexStr2Byte)*/ /*然后,我们再修订以上测试代码*/ System.out.println("***********************************************"); String encryptResultStr = parseByte2HexStr(encryptResult); System.out.println("加密后:" + encryptResultStr); byte[] decryptFrom = parseHexStr2Byte(encryptResultStr); decryptResult = decrypt(decryptFrom,password);//解码 System.out.println("解密后:" + new String(decryptResult)); } /** * 加密 * @method encrypt * @param content 需要加密的内容 * @param password 加密密码 * @return * @throws * @since v1.0 */ public static byte[] encrypt(String content, String password){ try { KeyGenerator kgen = KeyGenerator.getInstance("AES"); kgen.init(128, new SecureRandom(password.getBytes())); SecretKey secretKey = kgen.generateKey(); byte[] enCodeFormat = secretKey.getEncoded(); SecretKeySpec key = new SecretKeySpec(enCodeFormat, "AES"); Cipher cipher = Cipher.getInstance("AES");// 创建密码器 byte[] byteContent = content.getBytes("utf-8"); cipher.init(Cipher.ENCRYPT_MODE, key);// 初始化 byte[] result = cipher.doFinal(byteContent); return result; // 加密 } catch (NoSuchAlgorithmException e) { e.printStackTrace(); }catch (NoSuchPaddingException e) { e.printStackTrace(); }catch (UnsupportedEncodingException e) { e.printStackTrace(); }catch (InvalidKeyException e) { e.printStackTrace(); }catch (IllegalBlockSizeException e) { e.printStackTrace(); }catch (BadPaddingException e) { e.printStackTrace(); } return null; } /** * 解密 * @method decrypt * @param content 待解密内容 * @param password 解密密钥 * @return * @throws * @since v1.0 */ public static byte[] decrypt(byte[] content, String password){ try { KeyGenerator kgen = KeyGenerator.getInstance("AES"); kgen.init(128, new SecureRandom(password.getBytes())); SecretKey secretKey = kgen.generateKey(); byte[] enCodeFormat = secretKey.getEncoded(); SecretKeySpec key = new SecretKeySpec(enCodeFormat, "AES"); Cipher cipher = Cipher.getInstance("AES");// 创建密码器 cipher.init(Cipher.DECRYPT_MODE, key);// 初始化 byte[] result = cipher.doFinal(content); return result; // 解密 } catch (NoSuchAlgorithmException e) { e.printStackTrace(); }catch (NoSuchPaddingException e) { e.printStackTrace(); }catch (InvalidKeyException e) { e.printStackTrace(); }catch (IllegalBlockSizeException e) { e.printStackTrace(); }catch (BadPaddingException e) { e.printStackTrace(); } return null; } /** * 将二进制转换成16进制 * @method parseByte2HexStr * @param buf * @return * @throws * @since v1.0 */ public static String parseByte2HexStr(byte buf[]){ StringBuffer sb = new StringBuffer(); for(int i = 0; i < buf.length; i++){ String hex = Integer.toHexString(buf[i] & 0xFF); if (hex.length() == 1) { hex = '0' + hex; } sb.append(hex.toUpperCase()); } return sb.toString(); } /** * 将16进制转换为二进制 * @method parseHexStr2Byte * @param hexStr * @return * @throws * @since v1.0 */ public static byte[] parseHexStr2Byte(String hexStr){ if(hexStr.length() < 1) return null; byte[] result = new byte[hexStr.length()/2]; for (int i = 0;i< hexStr.length()/2; i++) { int high = Integer.parseInt(hexStr.substring(i*2, i*2+1), 16); int low = Integer.parseInt(hexStr.substring(i*2+1, i*2+2), 16); result[i] = (byte) (high * 16 + low); } return result; } /** * 另外一种加密方式--这种加密方式有两种限制 * 1、密钥必须是16位的 * 2、待加密内容的长度必须是16的倍数,如果不是16的倍数,就会出如下异常 * javax.crypto.IllegalBlockSizeException: Input length not multiple of 16 bytes at com.sun.crypto.provider.SunJCE_f.a(DashoA13*..) at com.sun.crypto.provider.SunJCE_f.b(DashoA13*..) at com.sun.crypto.provider.SunJCE_f.b(DashoA13*..) at com.sun.crypto.provider.AESCipher.engineDoFinal(DashoA13*..) at javax.crypto.Cipher.doFinal(DashoA13*..) 要解决如上异常,可以通过补全传入加密内容等方式进行避免。 * @method encrypt2 * @param content 需要加密的内容 * @param password 加密密码 * @return * @throws * @since v1.0 */ public static byte[] encrypt2(String content, String password){ try { SecretKeySpec key = new SecretKeySpec(password.getBytes(), "AES"); Cipher cipher = Cipher.getInstance("AES/ECB/NoPadding"); byte[] byteContent = content.getBytes("utf-8"); cipher.init(Cipher.ENCRYPT_MODE, key);// 初始化 byte[] result = cipher.doFinal(byteContent); return result; // 加密 } catch (NoSuchAlgorithmException e) { e.printStackTrace(); } catch (NoSuchPaddingException e) { e.printStackTrace(); } catch (UnsupportedEncodingException e) { e.printStackTrace(); } catch (InvalidKeyException e) { e.printStackTrace(); } catch (IllegalBlockSizeException e) { e.printStackTrace(); } catch (BadPaddingException e) { e.printStackTrace(); } return null; } }
测试效果:
解密后:宋建勇
***********************************************
javax.crypto.IllegalBlockSizeException: Input length must be multiple of 16 when decrypting with padded cipher
at com.sun.crypto.provider.SunJCE_f.b(DashoA13*..)
at com.sun.crypto.provider.SunJCE_f.b(DashoA13*..)
at com.sun.crypto.provider.AESCipher.engineDoFinal(DashoA13*..)
at javax.crypto.Cipher.doFinal(DashoA13*..)
at cn.com.songjy.test.ASCHelper.decrypt(ASCHelper.java:141)
at cn.com.songjy.test.ASCHelper.main(ASCHelper.java:58)
java.lang.NullPointerException
at java.lang.String.<init>(String.java:594)
at cn.com.songjy.test.ASCHelper.main(ASCHelper.java:59)
***********************************************
加密后:961000B09BDDA1F81E81EF3EFDC3A926
解密后:宋建勇