Imports System
Imports System.Text
Imports System.Security.Cryptography

Namespace RSACryptoServiceProvider_Examples
    Class MyMainClass
        Shared Sub Main()
            Dim toEncrypt() As Byte
            Dim encrypted() As Byte
            Dim signature() As Byte
            'Choose a small amount of data to encrypt.
            Dim original As String = "Hello"
            Dim myAscii As New ASCIIEncoding()

            'Create a sender and receiver.
            Dim mySender As New Sender()
            Dim myReceiver As New Receiver()

            'Convert the data string to a byte array.
            toEncrypt = myAscii.GetBytes(original)

            'Encrypt data using receiver's public key.
            encrypted = mySender.EncryptData(myReceiver.PublicParameters, toEncrypt)

            'Hash the encrypted data and generate a signature on the hash
            ' using the sender's private key.
            signature = mySender.HashAndSign(encrypted)

            Console.WriteLine("Original: {0}", original)

            'Verify the signature is authentic using the sender's public key.
            If myReceiver.VerifyHash(mySender.PublicParameters, encrypted, signature) Then
                'Decrypt the data using the receiver's private key.
                myReceiver.DecryptData(encrypted)
            Else
                Console.WriteLine("Invalid signature")
            End If
        End Sub 'Main
    End Class 'MyMainClass

    Class Sender
        Private rsaPubParams As RSAParameters
        Private rsaPrivateParams As RSAParameters

        Public Sub New()
            Dim rsaCSP As New RSACryptoServiceProvider()

            'Generate public and private key data.
            rsaPrivateParams = rsaCSP.ExportParameters(True)
            rsaPubParams = rsaCSP.ExportParameters(False)
        End Sub 'New

        Public ReadOnly Property PublicParameters() As RSAParameters
            Get
                Return rsaPubParams
            End Get
        End Property

        'Manually performs hash and then signs hashed value.
        Public Function HashAndSign(ByVal encrypted() As Byte) As Byte()
            Dim rsaCSP As New RSACryptoServiceProvider()
            Dim hash As New SHA1Managed()
            Dim hashedData() As Byte

            rsaCSP.ImportParameters(rsaPrivateParams)

            hashedData = hash.ComputeHash(encrypted)
            Return rsaCSP.SignHash(hashedData, CryptoConfig.MapNameToOID("SHA1"))
        End Function 'HashAndSign

        'Encrypts using only the public key data.
        Public Function EncryptData(ByVal rsaParams As RSAParameters, ByVal toEncrypt() As Byte) As Byte()
            Dim rsaCSP As New RSACryptoServiceProvider()

            rsaCSP.ImportParameters(rsaParams)
            Return rsaCSP.Encrypt(toEncrypt, False)
        End Function 'EncryptData
    End Class 'Sender

    Class Receiver
        Private rsaPubParams As RSAParameters
        Private rsaPrivateParams As RSAParameters

        Public Sub New()
            Dim rsaCSP As New RSACryptoServiceProvider()

            'Generate public and private key data.
            rsaPrivateParams = rsaCSP.ExportParameters(True)
            rsaPubParams = rsaCSP.ExportParameters(False)
        End Sub 'New

        Public ReadOnly Property PublicParameters() As RSAParameters
            Get
                Return rsaPubParams
            End Get
        End Property

        'Manually performs hash and then verifies hashed value.
        Public Function VerifyHash(ByVal rsaParams As RSAParameters, ByVal signedData() As Byte, ByVal signature() As Byte) As Boolean
            Dim rsaCSP As New RSACryptoServiceProvider()
            Dim hash As New SHA1Managed()
            Dim hashedData() As Byte

            rsaCSP.ImportParameters(rsaParams)

            hashedData = hash.ComputeHash(signedData)
            Return rsaCSP.VerifyHash(hashedData, CryptoConfig.MapNameToOID("SHA1"), signature)
        End Function 'VerifyHash

        'Decrypt using the private key data.
        Public Sub DecryptData(ByVal encrypted() As Byte)
            Dim fromEncrypt() As Byte
            Dim roundTrip As String
            Dim myAscii As New ASCIIEncoding()
            Dim rsaCSP As New RSACryptoServiceProvider()

            rsaCSP.ImportParameters(rsaPrivateParams)
            fromEncrypt = rsaCSP.Decrypt(encrypted, False)
            roundTrip = myAscii.GetString(fromEncrypt)

            Console.WriteLine("RoundTrip: {0}", roundTrip)
        End Sub 'DecryptData
    End Class 'Receiver
End Namespace 'RSACryptoServiceProvider_Examples

using System;
using System.Text;
using System.Security.Cryptography;

namespace RSACryptoServiceProvider_Examples
{
    class MyMainClass
    {
        static void Main()
        {
            byte[] toEncrypt;
            byte[] encrypted;
            byte[] signature;
            //Choose a small amount of data to encrypt.
            string original = "Hello";
            ASCIIEncoding myAscii = new ASCIIEncoding();

            //Create a sender and receiver.
            Sender mySender = new Sender();
            Receiver myReceiver = new Receiver();

            //Convert the data string to a byte array.
            toEncrypt = myAscii.GetBytes(original);

            //Encrypt data using receiver's public key.
            encrypted = mySender.EncryptData(myReceiver.PublicParameters, toEncrypt);

            //Hash the encrypted data and generate a signature on the hash
            // using the sender's private key.
            signature = mySender.HashAndSign(encrypted);

            Console.WriteLine("Original: {0}", original);

            //Verify the signature is authentic using the sender's public key.
            if(myReceiver.VerifyHash(mySender.PublicParameters, encrypted, signature))
            {
                //Decrypt the data using the receiver's private key.
                myReceiver.DecryptData(encrypted);
            }
            else
            {
                Console.WriteLine("Invalid signature");
            }
        }
    }

    class Sender
    {
        RSAParameters rsaPubParams;
        RSAParameters rsaPrivateParams;

        public Sender()
        {
            RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();

            //Generate public and private key data.
            rsaPrivateParams = rsaCSP.ExportParameters(true);
            rsaPubParams = rsaCSP.ExportParameters(false);
        }

        public RSAParameters PublicParameters
        {
            get
            {
                return rsaPubParams;
            }
        }

        //Manually performs hash and then signs hashed value.
        public byte[] HashAndSign(byte[] encrypted)
        {
            RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();
            SHA1Managed hash = new SHA1Managed();
            byte[] hashedData;

            rsaCSP.ImportParameters(rsaPrivateParams);

            hashedData = hash.ComputeHash(encrypted);
            return rsaCSP.SignHash(hashedData, CryptoConfig.MapNameToOID("SHA1"));
        }

        //Encrypts using only the public key data.
        public byte[] EncryptData(RSAParameters rsaParams, byte[] toEncrypt)
        {
            RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();

            rsaCSP.ImportParameters(rsaParams);
            return rsaCSP.Encrypt(toEncrypt, false);
        }
    }

    class Receiver
    {
        RSAParameters rsaPubParams;
        RSAParameters rsaPrivateParams;

        public Receiver()
        {
            RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();

            //Generate public and private key data.
            rsaPrivateParams = rsaCSP.ExportParameters(true);
            rsaPubParams = rsaCSP.ExportParameters(false);
        }

        public RSAParameters PublicParameters
        {
            get
            {
                return rsaPubParams;
            }
        }

        //Manually performs hash and then verifies hashed value.
        public bool VerifyHash(RSAParameters rsaParams, byte[] signedData, byte[] signature)
        {
            RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();
            SHA1Managed hash = new SHA1Managed();
            byte[] hashedData;

            rsaCSP.ImportParameters(rsaParams);

            hashedData = hash.ComputeHash(signedData);
            return rsaCSP.VerifyHash(hashedData, CryptoConfig.MapNameToOID("SHA1"), signature);
        }

        //Decrypt using the private key data.
        public void DecryptData(byte[] encrypted)
        {
            byte[] fromEncrypt;
            string roundTrip;
            ASCIIEncoding myAscii = new ASCIIEncoding();
            RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();

            rsaCSP.ImportParameters(rsaPrivateParams);
            fromEncrypt = rsaCSP.Decrypt(encrypted, false);
            roundTrip = myAscii.GetString(fromEncrypt);

            Console.WriteLine("RoundTrip: {0}", roundTrip);
        }
    }
}

#using <System.dll>

using namespace System;
using namespace System::Text;
using namespace System::Security::Cryptography;
ref class Sender
{
private:
   RSAParameters rsaPubParams;
   RSAParameters rsaPrivateParams;

public:
   Sender()
   {
      RSACryptoServiceProvider^ rsaCSP = gcnew RSACryptoServiceProvider;

      //Generate public and private key data.
      rsaPrivateParams = rsaCSP->ExportParameters( true );
      rsaPubParams = rsaCSP->ExportParameters( false );
   }


   property RSAParameters PublicParameters 
   {
      RSAParameters get()
      {
         return rsaPubParams;
      }

   }

   //Manually performs hash and then signs hashed value.
   array<Byte>^ HashAndSign( array<Byte>^encrypted )
   {
      RSACryptoServiceProvider^ rsaCSP = gcnew RSACryptoServiceProvider;
      SHA1Managed^ hash = gcnew SHA1Managed;
      array<Byte>^hashedData;
      rsaCSP->ImportParameters( rsaPrivateParams );
      hashedData = hash->ComputeHash( encrypted );
      return rsaCSP->SignHash( hashedData, CryptoConfig::MapNameToOID( "SHA1" ) );
   }


   //Encrypts using only the public key data.
   array<Byte>^ EncryptData( RSAParameters rsaParams, array<Byte>^toEncrypt )
   {
      RSACryptoServiceProvider^ rsaCSP = gcnew RSACryptoServiceProvider;
      rsaCSP->ImportParameters( rsaParams );
      return rsaCSP->Encrypt( toEncrypt, false );
   }

};

ref class Receiver
{
private:
   RSAParameters rsaPubParams;
   RSAParameters rsaPrivateParams;

public:
   Receiver()
   {
      RSACryptoServiceProvider^ rsaCSP = gcnew RSACryptoServiceProvider;

      //Generate public and private key data.
      rsaPrivateParams = rsaCSP->ExportParameters( true );
      rsaPubParams = rsaCSP->ExportParameters( false );
   }


   property RSAParameters PublicParameters 
   {
      RSAParameters get()
      {
         return rsaPubParams;
      }

   }

   //Manually performs hash and then verifies hashed value.
   bool VerifyHash( RSAParameters rsaParams, array<Byte>^signedData, array<Byte>^signature )
   {
      RSACryptoServiceProvider^ rsaCSP = gcnew RSACryptoServiceProvider;
      SHA1Managed^ hash = gcnew SHA1Managed;
      array<Byte>^hashedData;
      rsaCSP->ImportParameters( rsaParams );
      hashedData = hash->ComputeHash( signedData );
      return rsaCSP->VerifyHash( hashedData, CryptoConfig::MapNameToOID( "SHA1" ), signature );
   }


   //Decrypt using the private key data.
   void DecryptData( array<Byte>^encrypted )
   {
      array<Byte>^fromEncrypt;
      String^ roundTrip;
      ASCIIEncoding^ myAscii = gcnew ASCIIEncoding;
      RSACryptoServiceProvider^ rsaCSP = gcnew RSACryptoServiceProvider;
      rsaCSP->ImportParameters( rsaPrivateParams );
      fromEncrypt = rsaCSP->Decrypt( encrypted, false );
      roundTrip = myAscii->GetString( fromEncrypt );
      Console::WriteLine( "RoundTrip: {0}", roundTrip );
   }

};

int main()
{
   array<Byte>^toEncrypt;
   array<Byte>^encrypted;
   array<Byte>^signature;

   //Choose a small amount of data to encrypt.
   String^ original = "Hello";
   ASCIIEncoding^ myAscii = gcnew ASCIIEncoding;

   //Create a sender and receiver.
   Sender^ mySender = gcnew Sender;
   Receiver^ myReceiver = gcnew Receiver;

   //Convert the data string to a byte array.
   toEncrypt = myAscii->GetBytes( original );

   //Encrypt data using receiver's public key.
   encrypted = mySender->EncryptData( myReceiver->PublicParameters, toEncrypt );

   //Hash the encrypted data and generate a signature on the hash
   // using the sender's private key.
   signature = mySender->HashAndSign( encrypted );
   Console::WriteLine( "Original: {0}", original );

   //Verify the signature is authentic using the sender's public key.
   if ( myReceiver->VerifyHash( mySender->PublicParameters, encrypted, signature ) )
   {

      //Decrypt the data using the receiver's private key.
      myReceiver->DecryptData( encrypted );
   }
   else
   {
      Console::WriteLine( "Invalid signature" );
   }
}

package RSACryptoServiceProvider_Examples; 

import System.*;
import System.Text.*;
import System.Security.Cryptography.*;

class MyMainClass
{
    public static void main(String[] args)
    {
        ubyte toEncrypt[];
        ubyte encrypted[];
        ubyte signature[];

        // Choose a small amount of data to encrypt.
        String original = "Hello";
        ASCIIEncoding myAscii = new ASCIIEncoding();

        // Create a sender and receiver.
        Sender mySender = new Sender();
        Receiver myReceiver = new Receiver();

        // Convert the data string to a byte array.
        toEncrypt = myAscii.GetBytes(original);

        // Encrypt data using receiver's public key.
        encrypted = mySender.EncryptData(myReceiver.get_PublicParameters(),
            toEncrypt);

        // Hash the encrypted data and generate a signature on the hash
        // using the sender's private key.
        signature = mySender.HashAndSign(encrypted);
        Console.WriteLine("Original: {0}", original);

        // Verify the signature is authentic using the sender's public key.
        if (myReceiver.VerifyHash(mySender.get_PublicParameters(), 
                encrypted, signature)) {
            // Decrypt the data using the receiver's private key.
            myReceiver.DecryptData(encrypted);
        }
        else {
            Console.WriteLine("Invalid signature");
        }
    } //main
} //MyMainClass

class Sender
{
    private RSAParameters rsaPubParams;
    private RSAParameters rsaPrivateParams;

    public Sender()
    {
        RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();

        // Generate public and private key data.
        rsaPrivateParams = rsaCSP.ExportParameters(true);
        rsaPubParams = rsaCSP.ExportParameters(false);
    } //Sender

    /** @property 
     */
    public RSAParameters get_PublicParameters()
    {
        return rsaPubParams;
    } //get_PublicParameters

    // Manually performs hash and then signs hashed value.
    public ubyte[] HashAndSign(ubyte encrypted[])
    {
        RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();
        SHA1Managed hash = new SHA1Managed();
        ubyte hashedData[];

        rsaCSP.ImportParameters(rsaPrivateParams);
        hashedData = hash.ComputeHash(encrypted);
        return rsaCSP.SignHash(hashedData, CryptoConfig.MapNameToOID("SHA1"));
    } //HashAndSign

    // Encrypts using only the public key data.
    public ubyte[] EncryptData(RSAParameters rsaParams, ubyte toEncrypt[])
    {
        RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();

        rsaCSP.ImportParameters(rsaParams);
        return rsaCSP.Encrypt(toEncrypt, false);
    } //EncryptData
} //Sender

class Receiver
{
    private RSAParameters rsaPubParams;
    private RSAParameters rsaPrivateParams;

    public Receiver()
    {
        RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();

        // Generate public and private key data.
        rsaPrivateParams = rsaCSP.ExportParameters(true);
        rsaPubParams = rsaCSP.ExportParameters(false);
    } //Receiver

    /** @property 
     */
    public RSAParameters get_PublicParameters()
    {
        return rsaPubParams;
    } //get_PublicParameters

    // Manually performs hash and then verifies hashed value.
    public boolean VerifyHash(RSAParameters rsaParams, 
        ubyte signedData[], ubyte signature[])
    {
        RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();
        SHA1Managed hash = new SHA1Managed();
        ubyte hashedData[];

        rsaCSP.ImportParameters(rsaParams);
        hashedData = hash.ComputeHash(signedData);
        return rsaCSP.VerifyHash(hashedData, 
            CryptoConfig.MapNameToOID("SHA1"), signature);
    } //VerifyHash

    // Decrypt using the private key data.
    public void DecryptData(ubyte encrypted[])
    {
        ubyte fromEncrypt[];
        String roundTrip;
        ASCIIEncoding myAscii = new ASCIIEncoding();
        RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();

        rsaCSP.ImportParameters(rsaPrivateParams);
        fromEncrypt = rsaCSP.Decrypt(encrypted, false);
        roundTrip = myAscii.GetString(fromEncrypt);

        Console.WriteLine("RoundTrip: {0}", roundTrip);
    } //DecryptData
} //Receiver