Java-AESUtil

在线版 http://tool.chacuo.net/cryptaes

要使用 AES/CBC/PKCS7Padding 模式需要添加依赖

<!--AES/CBC/PKCS7Padding-->
<dependency>
    <groupId>org.bouncycastle</groupId>
    <artifactId>bcprov-jdk16</artifactId>
    <version>1.46</version>
</dependency>

AES 工具类

// 加密算法
private static final String ENCRY_ALGORITHM = "AES";
// 加密算法/加密模式/填充类型
private static final String CIPHER_MODE = "AES/CBC/PKCS7Padding";
// 设置iv偏移量，ECB加密模式不需要设置 iv 偏移量
private static final String IV = "0000000000000000";
// 设置加密字符集
private static final String CHARACTER = "UTF-8";
// 加密密码长度。默认 16 byte * 8 = 128 bit
private static final int PWD_SIZE = 16;

static {
    // 添加 AES/CBC/PKCS7Padding 支持
    Security.addProvider(new BouncyCastleProvider());
}

public static void main(String[] args) {
    String str = "NiHao";
    byte[] encryptAES = encryptAES(str, "1234567899874563");
    byte[] decryptAES = decryptAES(encryptAES, "1234567899874563");
    System.out.println(new String(decryptAES));
}

/**
 * 密码长度不足补"0"
 */
private static byte[] pwdHandler(String password) throws UnsupportedEncodingException {
    byte[] data = null;
    if (password == null) {
        password = "";
    }
    StringBuffer sb = new StringBuffer(PWD_SIZE);
    sb.append(password);
    while (sb.length() < PWD_SIZE) {
        sb.append("0");
    }
    if (sb.length() > PWD_SIZE) {
        sb.setLength(PWD_SIZE);
    }
    data = sb.toString().getBytes(CHARACTER);
    return data;
}

/**
 * AES 加密
 *
 * @param cleartext 明文
 * @param key       密钥
 * @return
 */
public static byte[] encryptAES(String cleartext, String key) {
    try {
        // 获取加密密钥
        SecretKeySpec keySpec = new SecretKeySpec(pwdHandler(key), ENCRY_ALGORITHM);
        // 获取Cipher实例
        Cipher cipher = Cipher.getInstance(CIPHER_MODE);

        // 查看数据块位数 默认为16（byte） * 8 =128 bit
        // System.out.println("数据块位数(byte)：" + cipher.getBlockSize());

        // 初始化Cipher实例。设置执行模式以及加密密钥
        cipher.init(Cipher.ENCRYPT_MODE, keySpec, new IvParameterSpec(IV.getBytes(CHARACTER)));
        // 执行
        byte[] cipherTextBytes = cipher.doFinal(cleartext.getBytes(CHARACTER));
        return cipherTextBytes;
    } catch (NoSuchPaddingException e) {
        e.printStackTrace();
    } catch (NoSuchAlgorithmException e) {
        e.printStackTrace();
    } catch (BadPaddingException e) {
        e.printStackTrace();
    } catch (IllegalBlockSizeException e) {
        e.printStackTrace();
    } catch (InvalidKeyException e) {
        e.printStackTrace();
    } catch (Exception e) {
        e.printStackTrace();
    }
    return null;
}

/**
 * AES 解密
 *
 * @param ciphertext 密文
 * @param key        密钥
 * @return
 */
public static byte[] decryptAES(byte[] ciphertext, String key) {
    try {
        // 获取解密密钥
        SecretKeySpec keySpec = new SecretKeySpec(pwdHandler(key), ENCRY_ALGORITHM);
        // 获取Cipher实例
        Cipher cipher = Cipher.getInstance(CIPHER_MODE);

        // 查看数据块位数 默认为16（byte） * 8 =128 bit
        // System.out.println("数据块位数(byte)：" + cipher.getBlockSize());

        // 初始化Cipher实例。设置执行模式以及加密密钥
        cipher.init(Cipher.DECRYPT_MODE, keySpec, new IvParameterSpec(IV.getBytes(CHARACTER)));
        // 执行
        byte[] clearTextBytes = cipher.doFinal(ciphertext);
        return clearTextBytes;
    } catch (NoSuchAlgorithmException e) {
        e.printStackTrace();
    } catch (InvalidKeyException e) {
        e.printStackTrace();
    } catch (NoSuchPaddingException e) {
        e.printStackTrace();
    } catch (BadPaddingException e) {
        e.printStackTrace();
    } catch (IllegalBlockSizeException e) {
        e.printStackTrace();
    } catch (Exception e) {
        e.printStackTrace();
    }
    // 解密错误 返回 null
    return null;
}

加密后通常配合 Base64 进行编码

public static void main(String[] args) {
    String str = "NiHao";
    byte[] encryptAES = encryptAES(str, "1234567899874563");
    String encryptBase64 = encryptBase64(encryptAES);

    byte[] decryptBase64 = decryptBase64(encryptBase64);
    byte[] decryptAES = decryptAES(decryptBase64, "1234567899874563");
    System.out.println(new String(decryptAES));
}

/**
 * BASE64 加密
 *
 * @param cleartext 明文
 * @return 密文
 */
public static String encryptBase64(byte[] cleartext) {
    BASE64Encoder base64Encoder = new BASE64Encoder();
    String cipherText = base64Encoder.encode(cleartext);
    return cipherText;
}

/**
 * BASE64 解密
 *
 * @param cipherText 密文
 * @return 明文
 */
public static byte[] decryptBase64(String cipherText) {
    try {
        BASE64Decoder base64Decoder = new BASE64Decoder();
        byte[] cipherTextBytes = base64Decoder.decodeBuffer(cipherText);
        return cipherTextBytes;
    } catch (IOException e) {
        e.printStackTrace();
    }
    // 解密错误返回 null
    return null;
}

也可以使用 16 进制编码

public static void main(String[] args) {
    String str = "NiHao";
    byte[] encryptAES = encryptAES(str, "1234567899874563");
    String encryptHex = encryptHex(encryptAES);

    byte[] decryptHex = decryptHex(encryptHex);
    byte[] decryptAES = decryptAES(decryptHex, "1234567899874563");
    System.out.println(new String(decryptAES));
}

/**
 * HEX 加密（字节数组转成16进制字符串）
 *
 * @param clearText 明文
 * @return 密文
 */
public static String encryptHex(byte[] clearText) {
    // 一个字节的数，
    StringBuffer sb = new StringBuffer(clearText.length * 2);
    String tmp = "";
    for (int n = 0; n < clearText.length; n++) {
        // 整数转成十六进制表示
        tmp = (java.lang.Integer.toHexString(clearText[n] & 0XFF));
        if (tmp.length() == 1) {
            sb.append("0");
        }
        sb.append(tmp);
    }
    // 转成大写
    String cipherText = sb.toString().toUpperCase();
    return cipherText;
}

/**
 * HEX 解密（16进制字符串转换成字节数组）
 *
 * @param cipherText 密文
 * @return 明文
 */
public static byte[] decryptHex(String cipherText) {
    if (cipherText == null || cipherText.length() < 2) {
        return new byte[0];
    }
    cipherText = cipherText.toLowerCase();
    int l = cipherText.length() / 2;
    byte[] cipherTextBytes = new byte[l];
    for (int i = 0; i < l; ++i) {
        String tmp = cipherText.substring(2 * i, 2 * i + 2);
        cipherTextBytes[i] = (byte) (Integer.parseInt(tmp, 16) & 0xFF);
    }
    return cipherTextBytes;
}

编码后若作为 URL 参数还需进行 URI 转换

public static String encodeURIComponent(String s) {
    String result = null;
    try {
        result = URLEncoder.encode(s, CHARACTER)
                .replaceAll("\\+", "%20")
                .replaceAll("\\%21", "!")
                .replaceAll("\\%27", "'")
                .replaceAll("\\%28", "(")
                .replaceAll("\\%29", ")")
                .replaceAll("\\%7E", "~");
    } catch (UnsupportedEncodingException e) {
        result = s;
    }
    return result;
}

public static String decodeURIComponent(String s) {
    if (s == null) {
        return null;
    }
    String result = null;
    try {
        result = URLDecoder.decode(s, CHARACTER);
    } catch (UnsupportedEncodingException e) {
        result = s;
    }
    return result;
}

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https://segmentfault.com/a/1190000015943620

https://blog.csdn.net/wangweiren_get/article/details/82585629