C # RSA 암호화 / 복호화 (전송 포함)

C # RSA 암호화 / 복호화 (전송 포함)

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System.Security.Cryptography.RSACryptoServiceProvider를 사용하는 C #의 인터넷에서 많은 암호화 / 암호 해독 자습서와 예제를 보았지만 할 수 있기를 바라는 것은 다음과 같습니다.

• RSA 공개 / 개인 키 쌍 만들기
• 공개 키 전송 (또는 개념 증명을 위해 문자열 변수로 이동)
• 새 RSA 암호화 공급자를 만들고 공개 키로 문자열을 암호화합니다.
• 암호화 된 문자열 (또는 데이터)을 원래 암호화 공급자에게 다시 전송하고 문자열을 해독합니다.

누구든지 이것에 대한 유용한 리소스를 알려줄 수 있습니까?

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이것에 대한 충분한 예가 있지만 어쨌든 여기 있습니다.

using System;
using System.Security.Cryptography;

namespace RsaCryptoExample
{
  static class Program
  {
    static void Main()
    {
      //lets take a new CSP with a new 2048 bit rsa key pair
      var csp = new RSACryptoServiceProvider(2048);

      //how to get the private key
      var privKey = csp.ExportParameters(true);

      //and the public key ...
      var pubKey = csp.ExportParameters(false);

      //converting the public key into a string representation
      string pubKeyString;
      {
        //we need some buffer
        var sw = new System.IO.StringWriter();
        //we need a serializer
        var xs = new System.Xml.Serialization.XmlSerializer(typeof(RSAParameters));
        //serialize the key into the stream
        xs.Serialize(sw, pubKey);
        //get the string from the stream
        pubKeyString = sw.ToString();
      }

      //converting it back
      {
        //get a stream from the string
        var sr = new System.IO.StringReader(pubKeyString);
        //we need a deserializer
        var xs = new System.Xml.Serialization.XmlSerializer(typeof(RSAParameters));
        //get the object back from the stream
        pubKey = (RSAParameters)xs.Deserialize(sr);
      }

      //conversion for the private key is no black magic either ... omitted

      //we have a public key ... let's get a new csp and load that key
      csp = new RSACryptoServiceProvider();
      csp.ImportParameters(pubKey);

      //we need some data to encrypt
      var plainTextData = "foobar";

      //for encryption, always handle bytes...
      var bytesPlainTextData = System.Text.Encoding.Unicode.GetBytes(plainTextData);

      //apply pkcs#1.5 padding and encrypt our data 
      var bytesCypherText = csp.Encrypt(bytesPlainTextData, false);

      //we might want a string representation of our cypher text... base64 will do
      var cypherText = Convert.ToBase64String(bytesCypherText);


      /*
       * some transmission / storage / retrieval
       * 
       * and we want to decrypt our cypherText
       */

      //first, get our bytes back from the base64 string ...
      bytesCypherText = Convert.FromBase64String(cypherText);

      //we want to decrypt, therefore we need a csp and load our private key
      csp = new RSACryptoServiceProvider();
      csp.ImportParameters(privKey);

      //decrypt and strip pkcs#1.5 padding
      bytesPlainTextData = csp.Decrypt(bytesCypherText, false);

      //get our original plainText back...
      plainTextData = System.Text.Encoding.Unicode.GetString(bytesPlainTextData);
    }
  }
}

참고로 Encrypt () 및 Decrypt ()에 대한 호출에는 OAEP와 PKCS # 1.5 패딩 사이를 전환하는 bool 매개 변수가 있습니다. 상황에서 사용할 수있는 경우 OAEP를 선택하는 것이 좋습니다.

---

public static string Encryption(string strText)
        {
            var publicKey = "<RSAKeyValue><Modulus>21wEnTU+mcD2w0Lfo1Gv4rtcSWsQJQTNa6gio05AOkV/Er9w3Y13Ddo5wGtjJ19402S71HUeN0vbKILLJdRSES5MHSdJPSVrOqdrll/vLXxDxWs/U0UT1c8u6k/Ogx9hTtZxYwoeYqdhDblof3E75d9n2F0Zvf6iTb4cI7j6fMs=</Modulus><Exponent>AQAB</Exponent></RSAKeyValue>";

            var testData = Encoding.UTF8.GetBytes(strText);

            using (var rsa = new RSACryptoServiceProvider(1024))
            {
                try
                {
                    // client encrypting data with public key issued by server                    
                    rsa.FromXmlString(publicKey.ToString());

                    var encryptedData = rsa.Encrypt(testData, true);

                    var base64Encrypted = Convert.ToBase64String(encryptedData);

                    return base64Encrypted;
                }
                finally
                {
                    rsa.PersistKeyInCsp = false;
                }
            }
        }

        public static string Decryption(string strText)
        {
            var privateKey = "<RSAKeyValue><Modulus>21wEnTU+mcD2w0Lfo1Gv4rtcSWsQJQTNa6gio05AOkV/Er9w3Y13Ddo5wGtjJ19402S71HUeN0vbKILLJdRSES5MHSdJPSVrOqdrll/vLXxDxWs/U0UT1c8u6k/Ogx9hTtZxYwoeYqdhDblof3E75d9n2F0Zvf6iTb4cI7j6fMs=</Modulus><Exponent>AQAB</Exponent><P>/aULPE6jd5IkwtWXmReyMUhmI/nfwfkQSyl7tsg2PKdpcxk4mpPZUdEQhHQLvE84w2DhTyYkPHCtq/mMKE3MHw==</P><Q>3WV46X9Arg2l9cxb67KVlNVXyCqc/w+LWt/tbhLJvV2xCF/0rWKPsBJ9MC6cquaqNPxWWEav8RAVbmmGrJt51Q==</Q><DP>8TuZFgBMpBoQcGUoS2goB4st6aVq1FcG0hVgHhUI0GMAfYFNPmbDV3cY2IBt8Oj/uYJYhyhlaj5YTqmGTYbATQ==</DP><DQ>FIoVbZQgrAUYIHWVEYi/187zFd7eMct/Yi7kGBImJStMATrluDAspGkStCWe4zwDDmdam1XzfKnBUzz3AYxrAQ==</DQ><InverseQ>QPU3Tmt8nznSgYZ+5jUo9E0SfjiTu435ihANiHqqjasaUNvOHKumqzuBZ8NRtkUhS6dsOEb8A2ODvy7KswUxyA==</InverseQ><D>cgoRoAUpSVfHMdYXW9nA3dfX75dIamZnwPtFHq80ttagbIe4ToYYCcyUz5NElhiNQSESgS5uCgNWqWXt5PnPu4XmCXx6utco1UVH8HGLahzbAnSy6Cj3iUIQ7Gj+9gQ7PkC434HTtHazmxVgIR5l56ZjoQ8yGNCPZnsdYEmhJWk=</D></RSAKeyValue>";

            var testData = Encoding.UTF8.GetBytes(strText);

            using (var rsa = new RSACryptoServiceProvider(1024))
            {
                try
                {                    
                    var base64Encrypted = strText;

                    // server decrypting data with private key                    
                    rsa.FromXmlString(privateKey);

                    var resultBytes = Convert.FromBase64String(base64Encrypted);
                    var decryptedBytes = rsa.Decrypt(resultBytes, true);
                    var decryptedData = Encoding.UTF8.GetString(decryptedBytes);
                    return decryptedData.ToString();
                }
                finally
                {
                    rsa.PersistKeyInCsp = false;
                }
            }
        }

---

솔직히, 파일에 키를 쓰는 것을 표시하는 튜토리얼이 거의 없기 때문에 구현하는 데 어려움이 있습니다. 받아 들여진 대답은 "좋다"였다. 그러나 나를 위해 두 키가 두 개의 개별 파일에 저장되도록 개선해야했습니다. 헬퍼 클래스를 작성 했으므로 복사하여 붙여 넣기 만하면됩니다. 이것이 도움이되기를 바랍니다.

using Microsoft.Win32;
using System;
using System.IO;
using System.Security.Cryptography;

namespace RsaCryptoExample
{
    class RSAFileHelper
    {
        readonly string pubKeyPath = "public.key";//change as needed
        readonly string priKeyPath = "private.key";//change as needed
        public void MakeKey()
        {
            //lets take a new CSP with a new 2048 bit rsa key pair
            RSACryptoServiceProvider csp = new RSACryptoServiceProvider(2048);

            //how to get the private key
            RSAParameters privKey = csp.ExportParameters(true);

            //and the public key ...
            RSAParameters pubKey = csp.ExportParameters(false);
            //converting the public key into a string representation
            string pubKeyString;
            {
                //we need some buffer
                var sw = new StringWriter();
                //we need a serializer
                var xs = new System.Xml.Serialization.XmlSerializer(typeof(RSAParameters));
                //serialize the key into the stream
                xs.Serialize(sw, pubKey);
                //get the string from the stream
                pubKeyString = sw.ToString();
                File.WriteAllText(pubKeyPath, pubKeyString);
            }
            string privKeyString;
            {
                //we need some buffer
                var sw = new StringWriter();
                //we need a serializer
                var xs = new System.Xml.Serialization.XmlSerializer(typeof(RSAParameters));
                //serialize the key into the stream
                xs.Serialize(sw, privKey);
                //get the string from the stream
                privKeyString = sw.ToString();
                File.WriteAllText(priKeyPath, privKeyString);
            }
        }
        public void EncryptFile(string filePath)
        {
            //converting the public key into a string representation
            string pubKeyString;
            {
                using (StreamReader reader = new StreamReader(pubKeyPath)){pubKeyString = reader.ReadToEnd();}
            }
            //get a stream from the string
            var sr = new StringReader(pubKeyString);

            //we need a deserializer
            var xs = new System.Xml.Serialization.XmlSerializer(typeof(RSAParameters));

            //get the object back from the stream
            RSACryptoServiceProvider csp = new RSACryptoServiceProvider();
            csp.ImportParameters((RSAParameters)xs.Deserialize(sr));
            byte[] bytesPlainTextData = File.ReadAllBytes(filePath);

            //apply pkcs#1.5 padding and encrypt our data 
            var bytesCipherText = csp.Encrypt(bytesPlainTextData, false);
            //we might want a string representation of our cypher text... base64 will do
            string encryptedText = Convert.ToBase64String(bytesCipherText);
            File.WriteAllText(filePath,encryptedText);
        }
        public void DecryptFile(string filePath)
        {
            //we want to decrypt, therefore we need a csp and load our private key
            RSACryptoServiceProvider csp = new RSACryptoServiceProvider();

            string privKeyString;
            {
                privKeyString = File.ReadAllText(priKeyPath);
                //get a stream from the string
                var sr = new StringReader(privKeyString);
                //we need a deserializer
                var xs = new System.Xml.Serialization.XmlSerializer(typeof(RSAParameters));
                //get the object back from the stream
                RSAParameters privKey = (RSAParameters)xs.Deserialize(sr);
                csp.ImportParameters(privKey);
            }
            string encryptedText;
            using (StreamReader reader = new StreamReader(filePath)) { encryptedText = reader.ReadToEnd(); }
            byte[] bytesCipherText = Convert.FromBase64String(encryptedText);

            //decrypt and strip pkcs#1.5 padding
            byte[] bytesPlainTextData = csp.Decrypt(bytesCipherText, false);

            //get our original plainText back...
            File.WriteAllBytes(filePath, bytesPlainTextData);
        }
    }
}

참조 URL : https://stackoverflow.com/questions/17128038/c-sharp-rsa-encryption-decryption-with-transmission