java - 用私钥文件解密 : invalid stream header

Question

在命令行中，我可以使用 openssl 加密和解密我的文件，如下所示:

创建 key :

openssl req -x509 -newkey rsa:2048 -keyout myKey.key -out myKey.crt -pubkey

加密:

cat myText.txt | openssl rsautl -encrypt -inkey myKey.crt -pubin >> encryptedtxt.enc

解密:

openssl rsautl -decrypt -inkey myKey.key -in encryptedtxt.enc > decryptedtxt.txt

我关注了 this tutorial

public static void main(String[] args) {

        String encryptedData = "..\\encryptedtxt.enc";
        File encryptedFIle = new File(encryptedData);

        try {
            byte[] data = Files.readAllBytes(encryptedFIle.toPath());
            PrivateKey privateKey = getPrivateKey();
            Cipher cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.DECRYPT_MODE, privateKey);
            byte[] decryptedData = cipher.doFinal(data);
            System.out.println(">" + new String(decryptedData));
        } catch (Exception e) {
            e.printStackTrace();
        }
    }


    private static PrivateKey getPrivateKey() {
        String privateKeyFilename = "\\myKey.key";
        FileInputStream fis = null;
        ObjectInputStream ois = null;
        File privateKeyFile = new File(privateKeyFilename);
        try {
            fis = new FileInputStream(privateKeyFile);
            ois = new ObjectInputStream(fis);
            BigInteger modulus = (BigInteger) ois.readObject();
            BigInteger exponent = (BigInteger) ois.readObject();
            RSAPrivateKeySpec rsaPrivateKeySpec = new RSAPrivateKeySpec(modulus, exponent);
            KeyFactory fact = KeyFactory.getInstance("RSA");
            PrivateKey privateKey = fact.generatePrivate(rsaPrivateKeySpec);
            return privateKey;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

运行时，出现以下问题:

java.io.StreamCorruptedException: invalid stream header: 2D2D2D2D
    at java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:857)
    at java.io.ObjectInputStream.<init>(ObjectInputStream.java:349)
    at Decryptor.getPrivateKey(TestClass.java:38)
    at Decryptor.main(TestClass.java:20)
java.security.InvalidKeyException: No installed provider supports this key: (null)
    at javax.crypto.Cipher.chooseProvider(Cipher.java:893)
    at javax.crypto.Cipher.init(Cipher.java:1249)
    at javax.crypto.Cipher.init(Cipher.java:1186)
    at Decryptor.main(TestClass.java:22)

有什么建议可以解决这个问题吗？

更新:

我修改了获取私钥的方法如下:

private static PrivateKey getPrivateKey() {
        String privateKeyFilename = "myKey.key";
        FileInputStream fis = null;
        ObjectInputStream ois = null;
        File privateKeyFile = new File(privateKeyFilename);
        try {
            String key = readFileAsString(privateKeyFilename);
            BASE64Decoder b64 = new BASE64Decoder();
            byte[] pkcs8EncodedBytes = b64.decodeBuffer(key);

            PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(pkcs8EncodedBytes);
            KeyFactory kf = KeyFactory.getInstance("RSA");
            PrivateKey privKey = kf.generatePrivate(keySpec);
            System.out.println(privKey);
            return privKey;

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

但是随后会抛出以下错误:

java.security.spec.InvalidKeySpecException: java.security.InvalidKeyException: IOException : Short read of DER length
    at sun.security.rsa.RSAKeyFactory.engineGeneratePrivate(RSAKeyFactory.java:217)
    at java.security.KeyFactory.generatePrivate(KeyFactory.java:372)
    at Decryptor.getPrivateKey(TestClass.java:61)
    at Decryptor.main(TestClass.java:19)
Caused by: java.security.InvalidKeyException: IOException : Short read of DER length
    at sun.security.pkcs.PKCS8Key.decode(PKCS8Key.java:351)
    at sun.security.pkcs.PKCS8Key.decode(PKCS8Key.java:356)
    at sun.security.rsa.RSAPrivateCrtKeyImpl.<init>(RSAPrivateCrtKeyImpl.java:91)
    at sun.security.rsa.RSAPrivateCrtKeyImpl.newKey(RSAPrivateCrtKeyImpl.java:75)
    at sun.security.rsa.RSAKeyFactory.generatePrivate(RSAKeyFactory.java:316)
    at sun.security.rsa.RSAKeyFactory.engineGeneratePrivate(RSAKeyFactory.java:213)
    ... 3 more
java.security.InvalidKeyException: No installed provider supports this key: (null)
    at javax.crypto.Cipher.chooseProvider(Cipher.java:893)
    at javax.crypto.Cipher.init(Cipher.java:1249)
    at javax.crypto.Cipher.init(Cipher.java:1186)
    at Decryptor.main(TestClass.java:21)

Answer 1

您正在尝试使用 ObjectInputStream 读取 key 。此类不用于通用解码；它只解码特定于 Java 的序列化格式。您看到的错误是 ObjectInputStream 通知您您正在读取的数据不是序列化的 Java 对象。

OpenSSL 生成的 key 文件不是Java 序列化对象。相反，它使用 PEM 编码。有关从 PEM 文件读取 key 的更多信息，请查看 Decrypting an OpenSSL PEM Encoded RSA private key with Java?