RSA加密每次密文不一样？

Question

string xmlPublicKey = "<RSAKeyValue><Modulus>uOMVRWVhMuGmnN7snAxmWmWb1cQejrExHlKnFcNxiXjx49nFRu7YCOovVCJBVNNa1g9b5BqU21KGBV7eArLmlTxGl1fzZU7KAG+HarctuBoCECVm7ViPVmAdfTSxo9hJco5uRVWECE4zB9JEA2c691E1jr3BLSyK5IfUS0/9a9k=</Modulus><Exponent>AQAB</Exponent></RSAKeyValue>";

string encodeStr = RSAEncrypt(xmlPublicKey, "password123");

Console.WriteLine(encodeStr);

////////RSA的加密函数  string
       static public string RSAEncrypt(string xmlPublicKey, string m_strEncryptString)
        {
            byte[] PlainTextBArray;
            byte[] CypherTextBArray;
            string Result;
            RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
            rsa.FromXmlString(xmlPublicKey);
            PlainTextBArray = (new UnicodeEncoding()).GetBytes(m_strEncryptString);
            CypherTextBArray = rsa.Encrypt(PlainTextBArray, false);
            Result = Convert.ToBase64String(CypherTextBArray);
            return Result;
        }

同一个公钥，为什么每次加密后出来的密文都不一样呢？

Answer 1

不一样就对了，一样才有问题。这和RSA算法采用的PADDING模式有关。

Answer 2

Hi ,

将 CypherTextBArray = rsa.Encrypt(PlainTextBArray, false);

换成 CypherTextBArray = rsa.Encrypt(PlainTextBArray, true);就好了

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Mike Feng
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Answer 3

你好！

RSA 每次加密不一样是正常，但用对应的密钥能解密出一样的内容。

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知识改变命运，奋斗成就人生!

Answer 4

你好，改成true后，仍然是每次不一样。不过知道不一样是正常就可以了，第一次接触RSA，所以比较疑惑而已