IAuthenticationModule.Authenticate(String, WebRequest, ICredentials) Método

Definição

Namespace:

System.Net

Assembly:

System.Net.Requests.dll

Retorna uma instância da classe Authorization em resposta a um desafio de autenticação de um servidor.

public:
 System::Net::Authorization ^ Authenticate(System::String ^ challenge, System::Net::WebRequest ^ request, System::Net::ICredentials ^ credentials);

public System.Net.Authorization? Authenticate (string challenge, System.Net.WebRequest request, System.Net.ICredentials credentials);

abstract member Authenticate : string * System.Net.WebRequest * System.Net.ICredentials -> System.Net.Authorization

Public Function Authenticate (challenge As String, request As WebRequest, credentials As ICredentials) As Authorization

Parâmetros

challenge

String

O desafio de autenticação enviado pelo servidor.

request

WebRequest

A instância de WebRequest associada ao desafio.

credentials

ICredentials

As credenciais associadas ao desafio.

Retornos

Authorization

Uma instância de Authorization que contém a mensagem de autorização da solicitação, ou null se o desafio não pode ser manipulado.

Exemplos

O exemplo a seguir mostra como usar o método Authenticate. Para obter um exemplo completo, consulte a AuthenticationManager classe .

// Authenticate is the core method for this custom authentication.
// When an internet resource requests authentication, the WebRequest::GetResponse
// method calls the AuthenticationManager::Authenticate method. This method, in
// turn, calls the Authenticate method on each of the registered authentication
// modules, in the order they were registered. When the authentication is
// complete an Authorization object is returned to the WebRequest, as
// shown by this routine's retun type.
virtual Authorization^ Authenticate( String^ challenge, WebRequest^ request, ICredentials^ credentials )
{
   Encoding^ ASCII = Encoding::ASCII;
   
   // Get the username and password from the credentials
   NetworkCredential^ MyCreds = credentials->GetCredential( request->RequestUri, "Basic" );
   if ( PreAuthenticate( request, credentials ) == nullptr )
         Console::WriteLine( "\n Pre-authentication is not allowed." );
   else
         Console::WriteLine( "\n Pre-authentication is allowed." );

   
   // Verify that the challenge satisfies the authorization requirements.
   bool challengeOk = checkChallenge( challenge, MyCreds->Domain );
   if (  !challengeOk )
         return nullptr;

   
   // Create the encrypted string according to the Basic authentication format as
   // follows:
   // a)Concatenate username and password separated by colon;
   // b)Apply ASCII encoding to obtain a stream of bytes;
   // c)Apply Base64 Encoding to this array of bytes to obtain the encoded
   // authorization.
   String^ BasicEncrypt = String::Concat( MyCreds->UserName, ":", MyCreds->Password );
   String^ BasicToken = String::Concat( "Basic ", Convert::ToBase64String( ASCII->GetBytes( BasicEncrypt ) ) );
   
   // Create an Authorization object using the above encoded authorization.
   Authorization^ resourceAuthorization = gcnew Authorization( BasicToken );
   
   // Get the Message property which contains the authorization string that the
   // client returns to the server when accessing protected resources
   Console::WriteLine( "\n Authorization Message: {0}", resourceAuthorization->Message );
   
   // Get the Complete property which is set to true when the authentication process
   // between the client and the server is finished.
   Console::WriteLine( "\n Authorization Complete: {0}", resourceAuthorization->Complete );
   
   Console::WriteLine( "\n Authorization ConnectionGroupId: {0}", resourceAuthorization->ConnectionGroupId );
   return resourceAuthorization;
}

// Authenticate is the core method for this custom authentication.
// When an Internet resource requests authentication, the WebRequest.GetResponse
// method calls the AuthenticationManager.Authenticate method. This method, in
// turn, calls the Authenticate method on each of the registered authentication
// modules, in the order in which they were registered. When the authentication is
// complete an Authorization object is returned to the WebRequest.
public Authorization Authenticate(String challenge, WebRequest request, ICredentials credentials)
{
  Encoding ASCII = Encoding.ASCII;

  // Get the username and password from the credentials
  NetworkCredential myCreds = credentials.GetCredential(request.RequestUri, "Basic");

  if (PreAuthenticate(request, credentials) == null)
    Console.WriteLine("\n Pre-authentication is not allowed.");
  else
    Console.WriteLine("\n Pre-authentication is allowed.");

  // Verify that the challenge satisfies the authorization requirements.
  bool challengeOk = CheckChallenge(challenge, myCreds.Domain);

  if (!challengeOk)
    return null;

  // Create the encrypted string according to the Basic authentication format as
  // follows:
  // a)Concatenate the username and password separated by colon;
  // b)Apply ASCII encoding to obtain a stream of bytes;
  // c)Apply Base64 encoding to this array of bytes to obtain the encoded
  // authorization.
  string basicEncrypt = myCreds.UserName + ":" + myCreds.Password;

  string basicToken = "Basic " + Convert.ToBase64String(ASCII.GetBytes(basicEncrypt));

  // Create an Authorization object using the encoded authorization above.
  Authorization resourceAuthorization = new Authorization(basicToken);

  // Get the Message property, which contains the authorization string that the
  // client returns to the server when accessing protected resources.
  Console.WriteLine("\n Authorization Message:{0}",resourceAuthorization.Message);

  // Get the Complete property, which is set to true when the authentication process
  // between the client and the server is finished.
  Console.WriteLine("\n Authorization Complete:{0}",resourceAuthorization.Complete);

  Console.WriteLine("\n Authorization ConnectionGroupId:{0}",resourceAuthorization.ConnectionGroupId);

  return resourceAuthorization;
}

  ' Authenticate is the core method for this custom authentication.
  ' When an Internet resource requests authentication, the WebRequest.GetResponse 
  ' method calls the AuthenticationManager.Authenticate method. This method, in 
  ' turn, calls the Authenticate method on each of the registered authentication
  ' modules, in the order in which they were registered. When the authentication is 
  ' complete an Authorization object is returned to the WebRequest.
  Public Function Authenticate(ByVal challenge As String, ByVal request As WebRequest, ByVal credentials As ICredentials) As Authorization _
      Implements IAuthenticationModule.Authenticate


    Dim ASCII As Encoding = Encoding.ASCII

    ' Get the username and password from the credentials
    Dim MyCreds As NetworkCredential = credentials.GetCredential(request.RequestUri, "Basic")

    If PreAuthenticate(request, credentials) Is Nothing Then
      Console.WriteLine(ControlChars.Lf + " Pre-authentication is not allowed.")
    Else
      Console.WriteLine(ControlChars.Lf + " Pre-authentication is allowed.")
    End If
    ' Verify that the challenge satisfies the authorization requirements.
    Dim challengeOk As Boolean = checkChallenge(challenge, MyCreds.Domain)

    If Not challengeOk Then
      Return Nothing
    End If

    ' Create the encrypted string according to the Basic authentication format as
    ' follows:
    ' a)Concatenate the username and password separated by colon;
    ' b)Apply ASCII encoding to obtain a stream of bytes;
    ' c)Apply Base64 encoding to this array of bytes to obtain the encoded 
    ' authorization.
    Dim BasicEncrypt As String = MyCreds.UserName + ":" + MyCreds.Password

    Dim BasicToken As String = "Basic " + Convert.ToBase64String(ASCII.GetBytes(BasicEncrypt))

    ' Create an Authorization object using the encoded authorization above.
    Dim resourceAuthorization As New Authorization(BasicToken)

    ' Get the Message property, which contains the authorization string that the 
    ' client returns to the server when accessing protected resources.
    Console.WriteLine(ControlChars.Lf + " Authorization Message:{0}", resourceAuthorization.Message)

    ' Get the Complete property, which is set to true when the authentication process 
    ' between the client and the server is finished.
    Console.WriteLine(ControlChars.Lf + " Authorization Complete:{0}", resourceAuthorization.Complete)

    Console.WriteLine(ControlChars.Lf + " Authorization ConnectionGroupId:{0}", resourceAuthorization.ConnectionGroupId)


    Return resourceAuthorization
  End Function 'Authenticate
End Class

Comentários

O Authenticate método conduz o processo de autenticação com o servidor e retorna uma Authorization instância para o AuthenticationManager.

Notas aos Implementadores

O AuthenticationManager chama o Authenticate(String, WebRequest, ICredentials) método em módulos de autenticação registrados para determinar qual módulo lida com o desafio. Se o módulo de autenticação não puder lidar com o desafio, o Authenticate(String, WebRequest, ICredentials) método deverá retornar null. Se o módulo de autenticação encontrar um erro ao conduzir o processo de autenticação, Authenticate(String, WebRequest, ICredentials) deverá gerar uma exceção.