为什么RSA加密可以返回用C＃和Java不同的结果？ [英] Why RSA encryption can return different results with C# and Java?

问题描述

我使用：

• C＃的RSACryptoServiceProvider


• JAVA ：KeyFactory.getInstance（RSA）+密码

我发送公钥（指数+模量）作为字节数组从Java到C＃ 。这没关系，有相同的字节。但是，当我尝试了一些数据与Java的一个键和C＃加密 - 有不同的结果。

I sending public key (exponent + modulus) as byte array from java to c#. It's ok, there is the same bytes. But when i try to encrypt some data with one key in Java and c# - there is different results.

Java的密钥生成：

Java Key Generation:

KeyPairGenerator keyGen = KeyPairGenerator.getInstance("RSA");
keyGen.initialize( Config.CRYPTO_KEY_NUM_BITS );

m_KeyPair = keyGen.genKeyPair();

m_PublicKey = KeyFactory.getInstance("RSA").generatePublic(
 newX509EncodedKeySpec(m_KeyPair.getPublic().getEncoded()));

byte[] exponent = m_PublicKey.getPublicExponent().toByteArray();
byte[] modulus  = m_PublicKey.getModulus().toByteArray(); // then sending...

C＃重点收到：

// Recieved...
m_ExternKey = new RSAParameters();
m_ExternKey.Exponent    = exponent;
m_ExternKey.Modulus     = modulus;

m_RsaExtern = new RSACryptoServiceProvider();
m_RsaExtern.ImportParameters(m_ExternKey);

byte[] test = m_RsaExtern.Encrypt(bytesToEncrypt, true);

和问题是加密的字节是不同的。

and problem is that encrypted bytes is different.

感谢您。

推荐答案

RSA加密是随机的。对于给定的公开密钥和给定的消息，每次尝试在加密产生字节的独特序列。这是正常的预期;随机字节被注入作为填充阶段的一部分，而不是注入随机字节将导致弱的加密系统。解密时，填充字节的位置和删除，原始邮件恢复毫发无损。

RSA encryption is randomized. For a given public key and a given message, each attempt at encryption yields a distinct sequence of bytes. This is normal and expected; random bytes are injected as part of the padding phase, and not injecting random bytes would result in a weak encryption system. During decryption, the padding bytes are located and removed, and the original message is recovered unscathed.

因此​​，预计您将获得与Java和C＃不同的加密邮件，而且，如果你运行Java或C＃代码的两倍。

Hence it is expected that you will get distinct encrypted messages with Java and C#, but also if you run your Java or C# code twice.

这篇关于为什么RSA加密可以返回用C＃和Java不同的结果？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！