Visual Guard Class Library Documentation

How to integrate Visual Guard in ASP.Net Web Site

To integrate Visual Guard in your ASP.Net Web Site, Web Application or Web Service project you have to:

Integration Demo

This demo shows how to integrate Visual Guard in ASP.Net Web site

How to integrate Visual Guard 

Referencing Visual Guard assemblies

In order to use Visual Guard, you must add references to Visual Guard assemblies:

Note: In the list of assemblies, Visual Studio will display different version of the Visual Guard assemblies. You must select the assembly corresponding to the version 2.0 of the framework.

Add Visual Guard assemblies

If the assemblies does not appear in this list you can use the Browse tab and select them in the directory <Visual Guard installation directory>/bin/2.0.

Description of Visual Guard assemblies:

Modifying the "web.config" file of your application 

To enable Visual Guard in your application, you must declare the class Novalys.VisualGuard.Security.WebForm.VGHttpModule n the list of HttpModules in the "web.config" of your application. To do that, you must:

<add type="Novalys.VisualGuard.Security.WebForm.VGHttpModule,Novalys.VisualGuard.Security.WebForm" name="VGModule"/>

For example:

<configuration>
  <system.web>
    ...
    <httpModules>
      <add type= "Novalys.VisualGuard.Security.WebForm.VGHttpModule,Novalys.VisualGuard.Security.WebForm" name="VGModule"/>
    </httpModules>
    ...
  </system.web>
</configuration>

This module will enable Visual Guard in your application. It will automatically detect the type of authentication used in your application. Visual Guard supports Forms, Windows and Passport authentication.

If you use Form authentication mode, you can use the Visual Guard authentication mechanism. In this case you must call the method VGSecurityManager.Authenticate in your login form. You can find an example of the authentication integrated in a login form in the chapter "Integrate Visual Guard in your code".

If you use Windows or Passport authentication mode, Visual Guard will automatically detect the authenticated user and load the security permissions granted to this user.

If the user does not have any role in the application or if the user is not declared in the repository or if the user is anonymous, Visual Guard will deny the user access to all pages in your web site.

If you want to allow anonymous sessions in your web site, you must declare an anonymous role to your application in the Visual Guard console.

To enable anonymous sessions, you must:

You can use Visual Guard in conjunction with the URL Authorization module to deny access to specific users (anonymous or not) or roles. Visual Guard users and roles are fully compatible with the URL Authorization module.

Configuring Membership

Visual Guard is fully compatible with Membership API and allows you to use the Web Site administration tools and Login ASP.Net controls (Login, LoginView, PasswordRecovery, CreateUserWizard ...). To use Membership features, you must declare VGMembershipProvider and VGRoleProvider in your web.config file.

 <configuration>
  <system.web>
    ...
    <roleManager defaultProvider="VGRoleProvider" enabled="true">
      <providers> 
           <add name="VGRoleProvider" type="Novalys.VisualGuard.Security.WebForm.VGRoleProvider, Novalys.VisualGuard.Security.WebForm" />
      </providers>
    </roleManager>
    ...
    <membership defaultProvider="VGMemberShipProvider">
      <providers> 
           <add name="VGMemberShipProvider" type="Novalys.VisualGuard.Security.WebForm.VGMemberShipProvider, Novalys.VisualGuard.Security.WebForm" />
      </providers>
    </membership>
    ...
  </system.web>
</configuration>

Integrating Visual Guard in your code

The main class in Visual Guard is Novalys.VisualGuard.Security.VGSecurityManager. This class provides the main access point for interacting with Visual Guard. It provides authentication and authorization features, it allows you to set the security of your application objects.

You have 3 types of code to integrate Visual Guard in your code:

To create a Login page

If you use Form Authentication mode, Visual Guard is fully compatible with Login ASP.Net controls (Login, LoginView, PasswordRecovery, CreateUserWizard ...).

If you want to use them, you must configure your web.config file as described in the previous chapter. You can also use your own controls or develop a custom form page.

The following example demonstrates how to authenticate a user. This code can be inserted in the click event of the OK button in a login form:

[C#]
Page.Validate();
if (!Page.IsValid) return;
VGAuthenticationState state = VGSecurityManager.Authenticate(usernameTextBox.Text, passwordTextBox.Text, VGAuthenticationMode.VisualGuard);
// Check if the authentication is failed.
if (state.IsFailed)
{
    FormsAuthentication.SignOut(); 
    // The username/password is invalid
    if (state.IsCredentialInvalid)
    {
        if (state.IsLastBadLogin)
        {
            // According to the password policy, the next bad login will lock the account
            errorLabel.Text = "Invalid user or password. The next bad login will lock your account.";
        }
        else
        {
            errorLabel.Text = "Invalid user or password";
        }
    }
    else if (state.IsUserNotAuthorized)
    {
        // The credentials are valid but the user does not have any role granted for the application
        errorLabel.Text = "You are not authorized to log on to this application";
    }
    else if (state.IsUserAccountExpired)
    {
        // The account of the user has expired
        errorLabel.Text = "Your account is no more valid. Contact your administrator";
    }
    else if (state.IsUserAccountNotYetAvailable)
    {
        // The account of the user is not yet available
        errorLabel.Text = "Your account is not yet available.";
    }
    else if (state.IsUserAccountLockedOut)
    {
        // The account of the user is locked out and must be unlocked by using the Visual Guard console.
        errorLabel.Text = "Your account is locked. Contact your administrator.";
    }
    else if (state.MustChangePasswordAtNextLogon)
    {
       // The user must change the password
       RedirectToChangePasswordPage();
    }
    errorLabel.Visible = true;
}
else
{
    if (!state.IsPasswordSecure)
    {
        // According to the password policy, the password is enough secure
        FormsAuthentication.SetAuthCookie(usernameTextBox.Text, remenberCheckBox.Checked);
        RedirectToChangePasswordPage();
    }
    else
    {
        FormsAuthentication.RedirectFromLoginPage(usernameTextBox.Text, remenberCheckBox.Checked);
    }
}


[Visual Basic]
 Page.Validate()
 If Not Page.IsValid Then Return
 Dim state As VGAuthenticationState = VGSecurityManager.Authenticate(usernameTextBox.Text, passwordTextBox.Text, VGAuthenticationMode.VisualGuard)
 ' Check if the authentication is failed.
 If state.IsFailed Then
    FormsAuthentication.SignOut(); 
    ' The username/password is invalid
    If state.IsCredentialInvalid Then
        If state.IsLastBadLogin Then
            ' According to the password policy, the next bad login will lock the account
            errorLabel.Text = "Invalid user or password. The next bad login will lock your account."
        Else
            errorLabel.Text = "Invalid user or password"
        End If
    ElseIf state.IsUserNotAuthorized Then
        ' The credentials are valid but the user does not have any role granted for the application
        errorLabel.Text = "You are not authorized to log on to this application"
    ElseIf state.IsUserAccountExpired Then
        ' The account of the user has expired
        errorLabel.Text = "Your account is no more valid. Contact your administrator"
    ElseIf state.IsUserAccountNotYetAvailable Then
        ' The account of the user is not yet available
        errorLabel.Text = "Your account is not yet available."
    ElseIf state.IsUserAccountLockedOut Then
        ' The account of the user is locked out and must be unlocked by using the Visual Guard console.
        errorLabel.Text = "Your account is locked. Contact your administrator."
     ElseIf state.MustChangePasswordAtNextLogon Then
        ' The user must change the password before reauthenticating
        RedirectToChangePasswordPage()
    End If
    errorLabel.Visible = True
Else
    If Not state.IsPasswordSecure Then
        ' According to the password policy, the password is enough secure
        FormsAuthentication.SetAuthCookie(usernameTextBox.Text, remenberCheckBox.Checked)
        RedirectToChangePasswordPage()
    Else
        FormsAuthentication.RedirectFromLoginPage(usernameTextBox.Text, remenberCheckBox.Checked)
    End If
End If

To secure your application objects

If you want to understand how Visual Guard sets the security of your application objects, see How Visual Guard secures an application.

How to filter granted roles

If a user has more than one role, by default Visual Guard creates a permission set that will be a union of all permission sets. If you want to select only one role or filter roles granted to the user, you can handle the event VGHttpModule.PermissionLoading. This event allows you to select roles granted to the user.
To handle this event you must declare <VGHTTPModuleName>_ PermissionLoading in the global.asax script (where <VGHTTPModuleName> is the name of the Visual Guard module declared in the web.config files, by default "VGModule").

The following example demonstrates how to select the role Administrator if this role is granted:
[Visual Basic]
Sub VGModule_PermissionLoading(ByVal sender As Object, ByVal e As VGPermissionsLoadingEventArgs)
    If e.Roles.Length > 1 Then
        Dim selectedRoles(1) As Novalys.VisualGuard.Security.VGGrantedRole 
        For Each role As Novalys.VisualGuard.Security.VGGrantedRole In e.Roles 
            If role.Name = "Administrator" Then
                selectedRoles(0) = role
                Exit For
            Else 
                If role.Name = "Member" Then
                    selectedRoles(0) = role
                    Exit For
                End If
            End If
        Next
        If selectedRoles(0) Is Nothing Then 
            e.Status = Novalys.VisualGuard.Security.VGAuthorizationStatus.ProcessCanceled
        Else 
            e.Roles = selectedRoles
        End If
    End If
End Sub

[C#]
void VGModule_PermissionLoading(object sender, VGPermissionsLoadingEventArgs args)
{
    if (e.Roles.Length > 1)
    { 
       Novalys.VisualGuard.Security.VGGrantedRole[] selectedRoles = new Novalys.VisualGuard.Security.VGGrantedRole[1];
       foreach (Novalys.VisualGuard.Security.VGGrantedRole role in e.Roles)
       {
        if (role.Name == "Administrator")
        { 
          selectedRoles[0] = role;
          break;
        }
        else if (role.Name == "Member")
        {
          selectedRoles[0] = role; 
          break; 
        }
      }
      if (selectedRoles[0] == null)
      {
         e.Status = Novalys.VisualGuard.Security.VGAuthorizationStatus.ProcessCanceled;
      }
      else 
      {
         e.Roles = selectedRoles; 
      }
    } 
}

Creating a repository and declaring the application

Once Visual Guard is integrated in your application, you can create the repository containing the information about the security of your application (users, roles, permissions ...). You must launch the Visual Guard console, right-click the root node in the treeview then select the option "Add repository".

After creating the repository, you must declare your application in the repository. Right-click the node corresponding to your repository then select the option "Connect...". After the connection, right-click on the repository node then select the option "Add application". At the end of the wizard, the console will generate 2 configuration files in the "bin" directory of your application.

Note: If you want to test the connection to this repository from your application, you will need to create a role for your application in the Visual Guard console and grant this role to a user. A user defined in the repository can access your application only when a role of the application is granted to this user.

Granting Read/Write permission to the Repository

Visual Guard needs to have Read/Write permissions to access the repository. For example, for a file based repository you must grant "Modify" permission to the directory containing the repository for ASP.NET user accounts. For a repository stored in a database, the user used to access the Visual Guard repository database must be a member of "vg_BasicAccess" role.

In most cases, you must grant this permission to "MACHINE\ASPNET" user account. If you use IIS 6.0 on Windows Server 2003 the user account is "NT Authority\Network Service". If you use impersonation, you must grant permission to "MACHINE\IUSR_<MACHINE>" for Form authentication mode and "Domain\UserName" for Windows integrated authentication mode.

To change permission to a directory, you must: