如何在AES128算法中生成64位加密密钥?

时间:2016-06-22 05:37:21

标签: java algorithm encryption aes aescryptoserviceprovider

我是加密概念的新手。我正在开发一个小项目,我需要使用AES128算法加密内容。接收器需要64位加密密钥进行解密 但是,我认为密钥是在基于String的AES128中生成的。那么如何生成一个64位的解密密钥呢?

我的代码如下所示

public class AESencrp {

    private static final String ALGO = "AES";
    private static byte[] keyValue = {};

    public static String encrypt(String Data, Key key) throws Exception {
        System.out.println("Key Encryp ============="
                + new String(key.getEncoded()));
        System.out.println("\n\n key in Enc ==========>" + key.getEncoded());
        Cipher c = Cipher.getInstance(ALGO);
        c.init(Cipher.ENCRYPT_MODE, key);
        byte[] encVal = c.doFinal(Data.getBytes());
        byte encryptedValue[] = new Base64().encode(encVal);
        return new String(encryptedValue);
    }

    public static String decrypt(String encryptedData, Key key)
            throws Exception {
        System.out.println("Key Decryp ============="
                + new String(key.getEncoded()));
        System.out.println("\n\n key in Dec ==========>" + key.getEncoded());
        Cipher c = Cipher.getInstance(ALGO);
        c.init(Cipher.DECRYPT_MODE, key);
        byte[] decordedValue = new Base64().decode(encryptedData.getBytes());
        byte[] decValue = c.doFinal(decordedValue);
        String decryptedValue = new String(decValue);
        return decryptedValue;
    }

    public static void main(String[] args) throws Exception {

        try {
            String sPrivateKey = "privateKey";
            keyValue = sPrivateKey.getBytes();
            MessageDigest sha = MessageDigest.getInstance("SHA-1");
            keyValue = sha.digest(keyValue);
            keyValue = Arrays.copyOf(keyValue, 16); // use only first 128 bit
        } catch (Exception e) {
            e.printStackTrace();
        }

        Key key = new SecretKeySpec(keyValue, ALGO);
        System.out.println("\n\n key in GK ==========>" + key.getEncoded());
        System.out.println("\n\n key in GK ==========>"
                + new String(key.getEncoded()));
        String password = "mypassword";
        String passwordEnc = encrypt(password, key);
        String passwordDec = decrypt(passwordEnc, key);

        System.out.println("Plain Text : " + password);
        System.out.println("Encrypted Text : " + passwordEnc);
        System.out.println("Decrypted Text : " + passwordDec);
    }

}

,结果如下,

 key in GK ==========>[B@a90653
 key in Enc ==========>[B@de6ced
 key in Dec ==========>[B@e80a59

 Plain Text : mypassword
 Encrypted Text : mBhBCUOlJbOBEaBl/42TZQ==
 Decrypted Text : mypassword

我需要与接收器分享哪一个?任何人都可以帮助我吗?

1 个答案:

答案 0 :(得分:0)

AES是一种对称加密算法。因此,对于加密和解密,密钥是相同的。所以,你不要生成"解密的关键,你需要"有"它

对于密钥传输,您可以使用RSA algorithm(或任何其他非对称密钥算法)。您需要在两侧都具有相同的关键组件。在您的情况下,有一个组件,即String (="privateKey")。因此,您需要告诉传输此组件,我建议使用非对称加密。

加密" privateKey"使用可以使用私钥解密的公钥。然后,使用此组件生成AES密钥。

详细了解RSA算法here