缺少前16个字符-Java AES CBC加密和golang解密

我使用以下代码在Java中加密和解密数据。加密和解密工作正常

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import javax.xml.bind.DatatypeConverter;
import java.security.SecureRandom;

public class MainNew {

    public static void main(String[] args) throws Exception{
        String iv = getEncryptionIV();
        System.out.println(" iv = "+iv);

        String encryptedData= encryptWithIVandKey(iv,encryptionKey,"hello world! golang is awesome!");
        System.out.println(encryptedData);
        String decryptedData = decrypt (iv,encryptionKey,encryptedData);
        System.out.println(decryptedData);
    }


    static final String encryptionKey = "rakesh1@n1111112";


    static byte[] doFinal(int encryptMode, SecretKey key, String iv, byte[] bytes) {

        try {
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
            cipher.init(encryptMode, key, new IvParameterSpec(DatatypeConverter.parseBase64Binary(iv)));
            byte[] data = cipher.doFinal(bytes);

            return data;

        } catch (Exception e) {
            e.printStackTrace();
            System.out.println(e);
        }
        return null;

    }



    static SecretKey generateKey(String passphrase) {

        SecretKey key = null;

        try {

            key = new SecretKeySpec(passphrase.getBytes("UTF-8"), "AES");


        } catch (Exception e) {
            e.printStackTrace();
            System.out.println(e);
        }

        return key;
    }




    static String getEncryptionIV() {
        SecureRandom random = new SecureRandom();
        byte[] ivBytes = new byte[16];
        random.nextBytes(ivBytes);
        return DatatypeConverter.printBase64Binary(ivBytes);
    }

    static String encryptWithIVandKey( String iv, String passphrase, final String strToEncrypt) {
        String encryptedStr = "";

        try {
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
            SecretKey key = generateKey(passphrase);
            cipher.init(Cipher.ENCRYPT_MODE, key, new IvParameterSpec(DatatypeConverter.parseBase64Binary(iv)));

            encryptedStr = DatatypeConverter.printBase64Binary(cipher.doFinal(strToEncrypt.getBytes("UTF-8")));

        } catch (Exception e) {
            e.printStackTrace();
            System.out.println(e);
        }


        return encryptedStr;
    }

    static String decrypt(String iv, String passphrase, String ciphertext) {
        try {
            SecretKey key = generateKey(passphrase);
            byte[] decrypted = doFinal(Cipher.DECRYPT_MODE, key, iv, DatatypeConverter.parseBase64Binary(ciphertext));
            return new String(decrypted, "UTF-8");
        } catch (Exception e) {
            e.printStackTrace();
            System.out.println(e);
        }
        return "";
    }

}

---

但如果我用密码在golang解密。解密值中缺少前16个字符。

来自您在游乐场中共享的Go代码：

// The IV needs to be unique, but not secure. Therefore it's common to
// include it at the beginning of the ciphertext.
...
iv := ciphertext[:aes.BlockSize]
ciphertext = ciphertext[aes.BlockSize:]

如您所见，这段代码期望密文的前16个字节是IV

但是，在Java代码中，您只需执行以下操作：

encryptedStr = DatatypeConverter.printBase64Binary(cipher.doFinal(strToEncrypt.getBytes("UTF-8")));

所以你加密字符串，这就是你返回的所有内容，然后在Go程序中使用

正如我们所看到的，Go代码正在从密文中删除16个字节，这就是您丢失数据的原因

我建议您更改Java代码，在字符串的开头包含IV，以符合Go代码的期望

您可以将Java中的encryptWithIVandKey方法更改为：

        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        SecretKey key = generateKey(passphrase);
        byte[] ivBytes = DatatypeConverter.parseBase64Binary(iv);
        cipher.init(Cipher.ENCRYPT_MODE, key, new IvParameterSpec(ivBytes));
        byte[] encBytes = cipher.doFinal(strToEncrypt.getBytes("UTF-8"));
        // concat iv + encripted bytes
        byte[] concat = new byte[ivBytes.length + encBytes.length];
        System.arraycopy(ivBytes, 0, concat, 0, ivBytes.length);
        System.arraycopy(encBytes, 0, concat, ivBytes.length, encBytes.length);
        encryptedStr = DatatypeConverter.printBase64Binary(concat);

这里的变化是，在编码到Base64之前，我们将IV+连接到加密字符串

由此产生的Base64是：

adAz5d5J3PAOuxntOe/9uMJgFHwIcdKobhRSKXwspmnxFlSlF40dtBYf9VSY34fU

---

如果您在Go代码中尝试该字符串，它将产生您期望的输出。

非常感谢！。我修改了我的golang代码。不从密文中提取IV。对，这是另一种选择：