JAVA实现AES加密算法代码.doc

JAVA实现AES加密算法代码 近些年DES使用越来越少，原因就在于其使用56位密钥，比较容易被破解，近些年来逐渐被AES替代，AES已经变成目前对称加密中最流行算法之一；AES可以使用128、192、和256位密钥，并且用128位分组加密和解密数据。本文就简单介绍如何通过JAVA实现AES加密。1. JAVA实现闲话少许，掠过AES加密原理及算法，关于这些直接搜索专业网站吧，我们直接看JAVA的具体实现。1.1 加密代码有详细解释，不多废话。/* 加密* param content 需要加密的内容* param password 加密密码* return*/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 (InvalidKeyException e) e.printStackTrace(); catch (UnsupportedEncodingException e) e.printStackTrace(); catch (IllegalBlockSizeException e) e.printStackTrace(); catch (BadPaddingException e) e.printStackTrace();return null;/* 加密* param content 需要加密的内容* param password 加密密码* return*/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 (InvalidKeyException e) e.printStackTrace(); catch (UnsupportedEncodingException e) e.printStackTrace(); catch (IllegalBlockSizeException e) e.printStackTrace(); catch (BadPaddingException e) e.printStackTrace();return null;2.2 解密代码有详细注释，不多废话注意：解密的时候要传入byte数组view plaincopy to clipboardprint?/*解密* param content 待解密内容* param password 解密密钥* return*/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; / 加密 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;/*解密* param content 待解密内容* param password 解密密钥* return*/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; / 加密 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;2.3 测试代码String content = test;String password = 12345678;/加密System.out.println(加密前： + content);byte encryptResult = encrypt(content, password);/解密byte decryptResult = decrypt(encryptResult,password);System.out.println(解密后： + new String(decryptResult);String content = test;String password = 12345678;/加密System.out.println(加密前： + content);byte encryptResult = encrypt(content, password);/解密byte decryptResult = decrypt(encryptResult,password);System.out.println(解密后： + new String(decryptResult);输出结果如下：加密前：test解密后：test2.4 容易出错的地方但是如果我们将测试代码修改一下，如下：String content = test;String password = 12345678;/加密System.out.println(加密前： + content);byte encryptResult = encrypt(content, password);try String encryptResultStr = new String(encryptResult,utf-8);/解密byte decryptResult = decrypt(encryptResultStr.getBytes(utf-8),password);System.out.println(解密后： + new String(decryptResult); catch (UnsupportedEncodingException e) e.printStackTrace();String content = test;String password = 12345678;/加密System.out.println(加密前： + content);byte encryptResult = encrypt(content, password);try String encryptResultStr = new String(encryptResult,utf-8);/解密byte decryptResult = decrypt(encryptResultStr.getBytes(utf-8),password);System.out.println(解密后： + new String(decryptResult); catch (UnsupportedEncodingException e) e.printStackTrace();则，系统会报出如下异常：javax.crypto.IllegalBlockSizeException: Input length must be multiple of 16 when decrypting with padded cipherat vider.SunJCE_f.b(DashoA13*.)at vider.SunJCE_f.b(DashoA13*.)at vider.AESCipher.engineDoFinal(DashoA13*.)at javax.crypto.Cipher.doFinal(DashoA13*.)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，主要有如下两个方法：2.4.1将二进制转换成16进制/*将二进制转换成16进制* param buf* return*/public static String parseByte2HexStr(byte buf) StringBuffer sb = new StringBuffer();for (int i = 0; i String hex = Integer.toHexString(bufi & 0xFF);if (hex.length() = 1) hex = 0 + hex;sb.append(hex.toUpperCase();return sb.toString();/*将二进制转换成16进制* param buf* return*/public static String parseByte2HexStr(byte buf) StringBuffer sb = new StringBuffer();for (int i = 0; i String hex = Integer.toHexString(bufi & 0xFF);if (hex.length() = 1) hex = 0 + hex;sb.append(hex.toUpperCase();return sb.toString();2.4.2 将16进制转换为二进制/*将16进制转换为二进制* param hexStr* return*/public static byte parseHexStr2Byte(String hexStr) if (hexStr.length() return null;byte result = new bytehexStr.length()/2;for (int i = 0;iint high = Integer.parseInt(hexStr.substring(i*2, i*2+1), 16);int low = Integer.parseInt(hexStr.substring(i*2+1, i*2+2), 16);resulti = (byte) (high * 16 + low);return result;/*将16进制转换为二进制* param hexStr* return*/public static byte parseHexStr2Byte(String hexStr) if (hexStr.length() return null;byte result = new bytehexStr.length()/2;for (int i = 0;iint high = Integer.parseInt(hexStr.substring(i*2, i*2+1), 16);int low = Integer.parseInt(hexStr.substring(i*2+1, i*2+2), 16);resulti = (byte) (high * 16 + low);return result;然后，我们再修订以上测试代码，如下：String content = test;String password = 12345678;/加密System.out.println(加密前： + content);byte encryptResult = encrypt(content, password);String encryptResultStr = parseByte2HexStr(encryptResult);System.out.println(加密后： + encryptResultStr);/解密byte decryptFrom = parseHexStr2Byte(encryptResultStr);byte decryptResult = decrypt(decryptFrom,password);System.out.println(解密后： + new String(decryptResult);String content = test;String password = 12345678;/加密System.out.println(加密前： + content);byte encryptResult = encrypt(content, password);String encryptResultStr = parseByte2HexStr(encryptResult);System.out.println(加密后： + encryptResultStr);/解密byte decryptFrom = parseHexStr2Byte(encryptResultStr);byte decryptResult = decrypt(decryptFrom,password);System.out.println(解密后： + new String(decryptResult);测试结果如下：加密前：test加密后：73C58BAFE578C59366D8C995CD0B9D6D解密后：test2.5 另外一种加密方式还有一种加密方式，大家可以参考如下：/* 加密* param content 需要加密的内容* param password 加密密码* return*/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 (InvalidKeyException e) e.printStackTrace(); catch (UnsupportedEncodingException e) e.printStackTrace(); catch (IllegalBlockSizeException e) e.printStackTrace(); catch (BadPaddingException e) e.printStackTrace();return null;/* 加密* param content 需要加密的内容* param password 加密密码* return*/public static byte encrypt2(String content, String password) try SecretKeySpec key = new SecretKeySpec(password.getBytes(), AES);Cipher c