在C#中创建的数字签名在Java验证中不匹配

Question

        RSACryptoServiceProvider RSA = new RSACryptoServiceProvider();

        RSA.FromXmlString(privateKey);

        var encoder = new UTF8Encoding();
        byte[] originalData = encoder.GetBytes(message);
        SHA1 sha1 = SHA1.Create();

        byte[] signedBytes = RSA.SignData(originalData, sha1);

        return signedBytes;

   //read xml file to get modulus and exponent bytes
            File publicKeyFileQA = new File(PUBLIC_KEY_FILE_QA);

            Map<String, BigInteger> publicKeyModulusExponentValues = DSXCRM_3YBP_Global_WebServicesUtil.readXMLFile(publicKeyFileQA);

            BigInteger publicKeyModulus = publicKeyModulusExponentValues.get("modulus");
            BigInteger publicKeyExponent = publicKeyModulusExponentValues.get("exponent");

            System.out.println("BigInteger Modulus : "+ publicKeyModulus + "BigInteger Exponent : " + publicKeyExponent);

            String messageWithSignature = (String) mapDataToPost.get("SignedMessage");
            String encryptedMessage = (String) mapDataToPost.get("EncryptedMessage");

            byte[] signatureBytes = DatatypeConverter.parseBase64Binary(messageWithSignature);

            System.out.println("Signature bytes : "+ new String(signatureBytes));


            byte[] cipherMessage = DatatypeConverter.parseBase64Binary(encryptedMessage);

            System.out.println("Cipher Message : "+ new String(cipherMessage));

            KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
            RSAPublicKeySpec publicKeySpec = new RSAPublicKeySpec(publicKeyModulus, publicKeyExponent);
            PublicKey publicKey = keyFactory.generatePublic(publicKeySpec);
            Signature sig = Signature.getInstance("SHA1withRSA");
            sig.initVerify(publicKey); //public key of sender
            sig.update(cipherMessage);

            boolean isRightSender = sig.verify(signatureBytes);
            System.out.println("isRightSender : "+isRightSender);

Answer 1

您正在读取一个名为“SignedMessage”的字段，将其存储在一个名为“MessageWithSignature”的变量中，然后将其视为签名。Blob中实际存在哪些数据？

您还可以像打印文本一样打印二进制数据（通过new String(byte[]))。对于消息字节（在验证器中似乎称为ciphermessage)和签名，您应该双面打印Base64或hex，以查看它们是否匹配。

如果切换到静态数据（以避免在读取时计算换行符之类的事情），那么这样做应该是有效的

byte[] originalData = Encoding.UTF8.GetBytes("This is a static message test.");
Console.WriteLine(Convert.ToBase64String(rsa.SignData(originalData), "SHA1"));

然后获取该输出，将其放入Java程序并验证

byte[] originalData = "This is a static message test.".getBytes("UTF-8");
byte[] signature = Base64.getDecoder().decode(theOutputFromTheCSharpProgram);
Signature verifier = new Signature("SHA1withRSA");
verifier.initVerify(publicKey);
verifier.update(originalData);
System.out.println(verifier.verify(signature));

如果该部分不起作用，那么您一定不能忠实地在两边表示相同的键。

RSA签名的二进制格式在C#和Java中是相同的；因此，一旦你得到了良好的数据传输，一切都应该工作。