Como: Personalizar o logon de usuário ao usar o serviço de autenticação do WCF

Artigo
10/15/2014

This topic shows how to validate customized credentials to authenticate users when you call the ASP.NET authentication service by using Windows Communication Foundation (WCF).Typically, authentication requires only a user name and password.However, in some cases you might have to verify a user's identity by using additional credentials, such as an identification number.

You use the WCF implementation of the authentication service when you want to log a user in from a client application that can send and consume a SOAP 1.1 message, such as a Java application.

To validate customized credentials for authentication

In the Global.asax file of the Web application, create an event handler for the Authenticating event.

In the handler, read the contents of the CustomCredential property of the handler's AuthenticatingEventArgs parameter, and then authenticate the values.

The following example shows how to read two authentication values from the CustomCredential property and then pass them to a custom authentication class named StudentAuthentication.

Sub AuthenticationService_Authenticating _
   (ByVal sender As Object, _
    ByVal e As System.Web.ApplicationServices.AuthenticatingEventArgs)
    Dim studentid As String = String.Empty
    Dim answer As String = String.Empty

    Dim credentials As String() = _
         e.CustomCredential.Split(New Char() {","c})
    If (credentials.Length > 0) Then
        studentid = credentials(0)
        If (credentials.Length > 1) Then
            answer = credentials(1)
        End If
    End If

    Try
        e.Authenticated = _
            StudentAuthentication.ValidateStudentCredentials _
            (e.Username, e.Password, studentid, answer)
    Catch ex As ArgumentNullException
        e.Authenticated = False
    End Try


    e.AuthenticationIsComplete = True
End Sub

void AuthenticationService_Authenticating(object sender, System.Web.ApplicationServices.AuthenticatingEventArgs e)
{
    string studentid = String.Empty;
    string answer = String.Empty;

    string[] credentials =
        e.CustomCredential.Split(new char[] { ',' });
    if (credentials.Length > 0)
    {
        studentid = credentials[0];
        if (credentials.Length > 1)
        {
            answer = credentials[1];
        }
    }

    try
    {
        e.Authenticated =
            StudentAuthentication.ValidateStudentCredentials
            (e.UserName, e.Password, studentid, answer);
    }
    catch (ArgumentNullException ex)
    {
        e.Authenticated = false;
    }

    e.AuthenticationIsComplete = true;
}

In the Application_Start method of the Global.asax file, bind the event handler for the Authenticating event.

The following example shows how to bind a handler to the Authenticating event.

Sub Application_Start(ByVal sender As Object, ByVal e As EventArgs)
    AddHandler System.Web.ApplicationServices.AuthenticationService.Authenticating, _
      AddressOf Me.AuthenticationService_Authenticating
End Sub

void Application_Start(object sender, EventArgs e) 
{
    System.Web.ApplicationServices.AuthenticationService.Authenticating += 
        new EventHandler<System.Web.ApplicationServices.AuthenticatingEventArgs>(AuthenticationService_Authenticating);

}

Call the authentication service from an application that can consume a SOAP message from a Web service, and pass the extra values to be authenticated in the CustomCredential property.

Compilando o código

You must set up the authentication service on a Web server for the previous examples to work.Para obter mais informações, consulte Como: Habilitar o serviço de autenticação do WCF.

Programação robusta

The previous code examples show a custom authentication class that throws the ArgumentNullException if any of the parameters are null.Your code must handle any exceptions that are raised during validation.

Segurança

Always access the authentication service by using the Secure Sockets Layer (SSL), using HTTPS protocol.

Consulte também

Conceitos

Visão geral do serviço de autenticação Windows Communication Foundation

Referência

AuthenticationService

AuthenticatingEventArgs

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