DSASignatureDeformatter.SetHashAlgorithm(String) Método

Definição

Namespace:

System.Security.Cryptography

Assembly:

System.Security.Cryptography.dll

Origem:

DSASignatureDeformatter.cs

Especifica o algoritmo de hash para o desformatador de assinatura DSA (Algoritmo de Assinatura Digital).

public:
 override void SetHashAlgorithm(System::String ^ strName);

public override void SetHashAlgorithm (string strName);

override this.SetHashAlgorithm : string -> unit

Public Overrides Sub SetHashAlgorithm (strName As String)

Parâmetros

strName

String

O nome do algoritmo de hash a ser usado para o desformatador de assinatura.

Exceções

CryptographicUnexpectedOperationException

O parâmetro strName não é mapeado para o algoritmo de hash SHA1.

Exemplos

#using <System.dll>

using namespace System;
using namespace System::Security::Cryptography;
int main()
{
   try
   {
      
      //Create a new instance of DSA.
      DSA^ DSA = DSA::Create();
      
      //The hash to sign.
      array<Byte>^Hash = {59,4,248,102,77,97,142,201,210,12,224,93,25,41,100,197,213,134,130,135};
      
      //Create an DSASignatureFormatter object and pass it the 
      //DSA instance to transfer the key information.
      DSASignatureFormatter^ DSAFormatter = gcnew DSASignatureFormatter( DSA );
      
      //Set the hash algorithm to SHA1.
      DSAFormatter->SetHashAlgorithm( "SHA1" );
      
      //Create a signature for HashValue and return it.
      array<Byte>^SignedHash = DSAFormatter->CreateSignature( Hash );
      
      //Create an DSASignatureDeformatter object and pass it the 
      //DSA instance to transfer the key information.
      DSASignatureDeformatter^ DSADeformatter = gcnew DSASignatureDeformatter( DSA );
      
      //Verify the hash and display the results to the console.
      if ( DSADeformatter->VerifySignature( Hash, SignedHash ) )
      {
         Console::WriteLine( "The signature was verified." );
      }
      else
      {
         Console::WriteLine( "The signature was not verified." );
      }
   }
   catch ( CryptographicException^ e ) 
   {
      Console::WriteLine( e->Message );
   }

}

using System;
using System.Security.Cryptography;

class DSASample
{
        
    static void Main()
    {
        try
        {
            //Create a new instance of DSA.
            DSA DSA = DSA.Create();

            //The hash to sign.
            byte[] Hash = {59,4,248,102,77,97,142,201,210,12,224,93,25,41,100,197,213,134,130,135};

            //Create an DSASignatureFormatter object and pass it the 
            //DSA instance to transfer the key information.
            DSASignatureFormatter DSAFormatter = new DSASignatureFormatter(DSA);

            //Set the hash algorithm to SHA1.
            DSAFormatter.SetHashAlgorithm("SHA1");

            //Create a signature for HashValue and return it.
            byte[] SignedHash = DSAFormatter.CreateSignature(Hash);

            //Create an DSASignatureDeformatter object and pass it the 
            //DSA instance to transfer the key information.
            DSASignatureDeformatter DSADeformatter = new DSASignatureDeformatter(DSA);

            //Verify the hash and display the results to the console.
            if(DSADeformatter.VerifySignature(Hash, SignedHash))
            {
                Console.WriteLine("The signature was verified.");
            }
            else
            {
                Console.WriteLine("The signature was not verified.");
            }
        }
        catch(CryptographicException e)
        {
            Console.WriteLine(e.Message);
        }
    }
}

Imports System.Security.Cryptography

 _

Class DSASample


    Shared Sub Main()
        Try
            'Create a new instance of DSA.
            Dim DSA As DSA = DSA.Create()

            'The hash to sign.
            Dim Hash As Byte() = {59, 4, 248, 102, 77, 97, 142, 201, 210, 12, 224, 93, 25, 41, 100, 197, 213, 134, 130, 135}

            'Create an DSASignatureFormatter object and pass it the 
            'DSA instance to transfer the key information.
            Dim DSAFormatter As New DSASignatureFormatter(DSA)

            'Set the hash algorithm to SHA1.
            DSAFormatter.SetHashAlgorithm("SHA1")

            'Create a signature for HashValue and return it.
            Dim SignedHash As Byte() = DSAFormatter.CreateSignature(Hash)

            'Create an DSASignatureDeformatter object and pass it the 
            'DSA instance to transfer the key information.
            Dim DSADeformatter As New DSASignatureDeformatter(DSA)

            'Verify the hash and display the results to the console.
            If DSADeformatter.VerifySignature(Hash, SignedHash) Then
                Console.WriteLine("The signature was verified.")
            Else
                Console.WriteLine("The signature was not verified.")
            End If

        Catch e As CryptographicException
            Console.WriteLine(e.Message)
        End Try
    End Sub
End Class

Notas aos Herdeiros

Este método não é usado. O DSA algoritmo requer o SHA1 algoritmo de hash.

Confira também

• Serviços criptográficos