解密使用 OpenSSL 生成的“der”文件时出现异常：使用填充密码解密时，输入长度必须是 8 的倍数

首先，我使用 OpenSSL 生成一个私有 RSA 密钥文件，然后将其转换为加密的“der”文件：

$ openssl pkcs8 -topk8 -inform PEM -outform DER -in private_key.pem -out private_key.der

接下来我尝试使用以下代码从 Java 解密该文件（在这个阶段我已经将该文件读入byte[] key使用本文底部代码的数组）：

public static byte[] decryptPrivateKey(byte[] key) throws IOException, NoSuchAlgorithmException, InvalidKeySpecException, NoSuchPaddingException, InvalidKeyException, InvalidAlgorithmParameterException, IllegalBlockSizeException, BadPaddingException {
    PBEKeySpec passKeySpec = new PBEKeySpec("p".toCharArray()); //my password

    EncryptedPrivateKeyInfo encryptedKey = new EncryptedPrivateKeyInfo(key);
    System.out.println(encryptedKey.getAlgName());
    //PBEWithMD5AndDES
    System.out.println("key length: " + key.length);
    //key length: 677
    SecretKeyFactory keyFac = SecretKeyFactory.getInstance(encryptedKey.getAlgName());
    SecretKey passKey = keyFac.generateSecret(passKeySpec);

     // Create PBE Cipher
    Cipher pbeCipher = Cipher.getInstance(encryptedKey.getAlgName());
    // Initialize PBE Cipher with key and parameters
    pbeCipher.init(Cipher.DECRYPT_MODE, passKey, encryptedKey.getAlgParameters());

    // Decrypt the private key(throws the exception)
    return pbeCipher.doFinal(key);
}

我在上面的 return 语句中得到以下堆栈跟踪：

Exception in thread "main" javax.crypto.IllegalBlockSizeException: Input length must be multiple of 8 when decrypting with padded cipher
    at com.sun.crypto.provider.CipherCore.doFinal(CipherCore.java:750)
    at com.sun.crypto.provider.CipherCore.doFinal(CipherCore.java:676)
    at com.sun.crypto.provider.PBECipherCore.doFinal(PBECipherCore.java:422)
    at com.sun.crypto.provider.PBEWithMD5AndDESCipher.engineDoFinal(PBEWithMD5AndDESCipher.java:316)
    at javax.crypto.Cipher.doFinal(Cipher.java:2087)
    at roland.test.crypto.Test.decryptPrivateKey(Test.java:96)
    at roland.test.crypto.Test.getPrivateKey(Test.java:74)
    at roland.test.crypto.Test.test(Test.java:58)
    at roland.test.crypto.Test.main(Test.java:30)

密钥以字节数组的形式从“der”文件中读取：

public static PrivateKey getPrivateKey() throws Exception {
    byte[] key = null;
    try(final InputStream resourceStream = getMyClass().getResourceAsStream("private_key.der")) { //$NON-NLS-1$\r
        key = ByteStreams.toByteArray(resourceStream);
    } catch (IOException e) {
        e.printStackTrace();
    }

    key = decryptPrivateKey(key);
}

解决办法是：

return pbeCipher.doFinal(encryptedKey.getEncryptedData());