c# - 使用 .NET 的 Java RSA/ECB/PKCS1Padding 加密

Question

我需要使用公钥对网站上的密码进行加密。公钥通过带有以下信息的 Java Web 服务提供: key 是与 RSA/ECB/PKCS1Padding 算法一起使用的 RSA key 。公钥以 JSON 的形式提供:

{
    "kid":"PWD",
    "kty":"RSA",
    "use":"enc",
    "n":"MTA0OTgzNjg0OTMxMzE2NjkwNTU4Mjg3NDIwMDg1NTY0ODEyMjg1MDk2NTcwNzU5NDIzNzM0O
    DA3OTA2MzA0MDczNTU0NDQ2Njg3ODY2ODk2NTk0NjYzNTAxMzg0NzE1OTExMjA0MjU1MzMzOTIzMjA
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    zcwMjA3MzQxOTcwNzc4NDAwNzM3MTY2NDMyNzIwNjMwMDQwOTMwOTQ0MTA2OTE1NDEzMDAwNTMyMTE
    5ODM0MTA2MjAzMDIyODEwMjYyMDM3MDQ0NzkxNzIzNTU1MjQyNjYxMzE2ODc4OTc5NzY1OTgzMjg4M
    zQ0NDc3OTYwNTg3MzE2NTUwMDgx",
    "e":"NjU1Mzc"
 }

我尝试使用公钥加密密码，但生成的 key 不正确。这是我的代码:

encryptedPassword = EncrypIt("Password01", "MTA1MzQxNzIwODA3NjUwNzg5ND
Y4ODU2Mjc0NDA3ODIwMjQ1ODQ5NDE1MDk1MDIzMTM3MjM0NzAwNzYzNjc2MTgwNjg3ODMxMjA3
NTY0NTcxMjg2MzM4NjQ1NzEwMDcyMjY2MTQyNDIzMTczMjkwMDk0MTc0MTA5MTc5MzI0NjYwMjQ4NzI3NzM0MTQ5NDY0MjUwODkwO
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
c2OTAzNjc3NzQzODM3NzM0MjE2ODM0NjY4MjM4MTQ0OTA3MDQ3MTk1Njc1NzU3OTE2NjEyNzkzMzM2MzI3MDUyNjg0NDI5NDExNjI
2MzA0MzM5", "NjU1Mzc");

    public static string EncrypIt(string password, string publicKey, string exponent)
    {
        UnicodeEncoding ByteConverter = new UnicodeEncoding();
        byte[] publicKeyByte = ByteConverter.GetBytes(publicKey);
        byte[] passwordByte = ByteConverter.GetBytes(password);

        RSACryptoServiceProvider RSA = new RSACryptoServiceProvider();
        RSAParameters RSAKeyInfo = new RSAParameters();
        RSAKeyInfo = RSA.ExportParameters(false); //Export only public key
        //Set RSAKeyInfo to the public key values. 
        RSAKeyInfo.Modulus = publicKeyByte;
        //RSAKeyInfo.Exponent = exponentBytes; //I tried to set exponent but I have an error
        RSA.ImportParameters(RSAKeyInfo);
        byte[] encryptedPassword = RSA.Encrypt(passwordByte, false);
        return Convert.ToBase64String(encryptedPassword);
    }

(json和我的代码公钥不一样，不用注意，我只是从不同来源复制信息)

• 我获得的加密密码太长:加密密码应该是 172 个字符(我知道是因为我有一个小的 Java 程序可以让我正确加密密码)但我得到了 1100 个字符。
• 我不使用指数:我应该吗？
• 我不能使用 JSON 直接正确配置 RSACryptoServiceProvider 吗？

owlstead 的回答帮助我获得了字符串大小正确的加密密码，但使用加密字符串的服务拒绝了它并显示消息:javax.crypto.IllegalBlockSizeException: Data must不超过 128 字节

我获得了执行正确加密的 java 程序的代码(见下文)。我需要使用 .NET 实现相同的加密。

public class EncryptionServiceImpl
{

    private static final Charset UTF8 = Charset.forName("UTF-8");

    @Resource(name = "briqueAuthentificationClient")
    private BriqueAuthentificationClientImpl briqueAuthentificationClient;

    protected static final String ALGORITHM_RSA = "RSA";

    protected static final String TRANSFORMATION_RSA_ECB_PKCS1PADDING = "RSA/ECB/PKCS1Padding";

    private static final Logger LOG = LoggerFactory.getLogger(EncryptionServiceImpl.class);

    public EncryptionServiceImpl() {
        LOG.info("constructeur EncryptionServiceImpl");
    }

    /**
     * @param briqueAuthentificationClient the briqueAuthentificationClient to set
     */
    public void setBriqueAuthentificationClient(final BriqueAuthentificationClientImpl briqueAuthentificationClient) {
        this.briqueAuthentificationClient = briqueAuthentificationClient;
    }

    public String encrypt(final String input) throws GeneralSecurityException {

        if (StringUtils.isNotBlank(input)) {
            final CertificateDto certificate = this.briqueAuthentificationClient.getCurrentCertificate();

            if (certificate != null) {
                return new String(this.encryptAndEncode(input.getBytes(), certificate), EncryptionServiceImpl.UTF8);
            } else {
                throw new RuntimeException("Certificate is null");
            }
        }
        return null;
    }

    protected byte[] encryptAndEncode(final byte[] input, final CertificateDto currentCertificate)
            throws GeneralSecurityException {

        // Création de la clé publique
        final PublicKey publicKey = this.buildPublicKey(currentCertificate);

        // Chiffre
        final byte[] inputEncrypted = this.encrypte(input, publicKey);

        // Encode
        return this.encodeBase64Url(inputEncrypted);
    }

    protected PublicKey buildPublicKey(final CertificateDto currentCertificate) throws GeneralSecurityException {

        if ("RSA".equals(currentCertificate.getKeyType())) {
            return this.buildRSAPublicKey(currentCertificate);
        }
        LOG.error(String.format("Tentative de création d'une clé publique avec un algorithme non connu [%s]",
                currentCertificate.getKeyType()));
        return null;
    }

    protected PublicKey buildRSAPublicKey(final CertificateDto currentCertificate) throws GeneralSecurityException {

        final BigInteger modulus = new BigInteger(new String(Base64.decodeBase64(currentCertificate.getModulus()),
                EncryptionServiceImpl.UTF8));
        final BigInteger publicExponent = new BigInteger(new String(Base64.decodeBase64(currentCertificate
                .getPublicExponent()), EncryptionServiceImpl.UTF8));

        try {
            return KeyFactory.getInstance(ALGORITHM_RSA).generatePublic(new RSAPublicKeySpec(modulus, publicExponent));
        } catch (InvalidKeySpecException e) {
            throw e;
        } catch (NoSuchAlgorithmException e) {
            throw e;
        }
    }

    protected byte[] encrypte(final byte[] input, final RSAPublicKeySpec rsaPublicKeySpec)
            throws GeneralSecurityException {

        PublicKey publicKey;
        try {
            publicKey = KeyFactory.getInstance(ALGORITHM_RSA).generatePublic(
                    new RSAPublicKeySpec(rsaPublicKeySpec.getModulus(), rsaPublicKeySpec.getPublicExponent()));
        } catch (InvalidKeySpecException e) {
            throw e;
        } catch (NoSuchAlgorithmException e) {
            throw e;
        }
        return this.encrypte(input, publicKey);
    }

    protected byte[] encrypte(final byte[] input, final PublicKey publicKey) throws GeneralSecurityException {

        try {
            final Cipher cipher = Cipher.getInstance(TRANSFORMATION_RSA_ECB_PKCS1PADDING);
            cipher.init(Cipher.ENCRYPT_MODE, publicKey);
            return cipher.doFinal(input);
        } catch (NoSuchAlgorithmException e) {
            throw e;
        } catch (NoSuchPaddingException e) {
            throw e;
        } catch (IllegalBlockSizeException e) {
            throw e;
        } catch (BadPaddingException e) {
            throw e;
        }

    }

    protected byte[] decrypte(final byte[] input, final RSAPrivateKeySpec rsaPrivateKeySpec)
            throws GeneralSecurityException {

        final BigInteger modulus = rsaPrivateKeySpec.getModulus();
        final BigInteger privateExponent = rsaPrivateKeySpec.getPrivateExponent();

        try {
            final PrivateKey privateKey = KeyFactory.getInstance(ALGORITHM_RSA).generatePrivate(
                    new RSAPrivateKeySpec(modulus, privateExponent));

            final Cipher cipher = Cipher.getInstance(TRANSFORMATION_RSA_ECB_PKCS1PADDING);
            cipher.init(Cipher.DECRYPT_MODE, privateKey);
            return cipher.doFinal(input);

        } catch (NoSuchAlgorithmException e) {
            throw e;
        } catch (NoSuchPaddingException e) {
            throw e;
        } catch (IllegalBlockSizeException e) {
            throw e;
        } catch (BadPaddingException e) {
            throw e;
        } catch (InvalidKeySpecException e) {
            throw e;
        } catch (InvalidKeyException e) {
            throw e;
        }

    }

    protected byte[] encodeBase64Url(final byte[] input) {
        return Base64.encodeBase64(input, false);
    }

    protected byte[] decodeBase64Url(final byte[] input) {
        return Base64.decodeBase64(input);
    }

    /**
     * Method to connect to an url
     * 
     * @param httpclient the http connection
     * @return the response GetMethod
     * @throws OAuthException in cas of connection error
     */
    private GetMethod connect(final HttpClient httpclient, final String url) {

        final GetMethod httpget = new GetMethod(url);
        try {

            httpclient.executeMethod(httpget);

        } catch (final UnknownHostException e) {
            throw new RuntimeException("Connection ERROR - Host could not be determined.", e);
        } catch (final IOException e) {
            throw new RuntimeException("Connection ERROR - Input/Output error.", e);
        }
        return httpget;
    }

}

我在 owlstead 的帮助下完成的步骤在下面的答案中。当我使用此 Java 程序对字符串 Password01 进行编码时，我获得了如下字符串:

sy5/XElHvuYA4Rbq8OBydLymT82R+z77jy6MU2sNal7VenzPEbARgy7p3zWgYgG13Cypk+zbnnB5L37fVUhgOgCqCyLtikzxJBNmPyzUK9+beiHJKyONZwifDzQ44hXTeXcZ0bmF9b5dLFy9QS/N5m28vIyBSGY8K2B7EB2FF38=  

这个加密后的密码可以在Java端解密

当我使用 .NET 代码时，字符串如下所示:

ACZXYj/KudyxKBB510SxSouKaVwssmEUM6Jpreh8jTtrIH9eGb18GIdkBU7rXzMuLYbAhyREbFLbR87zW/2DNa4tN97FOlqr6k1JppJ/SSS/9fGdMvSOAQbWjsxksDH7fRu9dCvK0m0exFtGfXG7Yua9bB1m0dTNiwCZUZM0LnEM  

此加密密码在 Java 端无法解密。失败并显示错误消息:

javax.crypto.IllegalBlockSizeException: Data must not be longer than 128 bytes

Answer 1

您首先需要使用 Convert.FromBase64String 执行 base 64 解码n和e，将结果从ASCII编码转换为字符串，然后使用BigInteger.parse解析结果.然后你可以使用 toByteArray 转换为字节，但要注意 BigInteger 是小端，and RSAParameters expects big endian , 所以你必须反转字节。

您的 .NET RSA 密文(您可能不应该反转)前面有一个值为 00h 的字节，这使其成为无效的密文。 RSA 密文必须 与 key 的字节长度完全相同。