How to integrate Visual Guard in your application

If your application is based on an ASP.Net 2.0Web Application project, you can consult the page "How to integrate Visual Guard in an ASP.Net 2.0 application".

To integrate Visual Guard in your application you must:

Add the assemblies of Visual Guard as references of your project.
Modify the "web.config" file of your application to integrate the Visual Guard module.
Integrate Visual Guard in the code of your application.
Create a Visual Guard repository and declare your application by using the Visual Guard console. This repository will contain all security items (users, roles, permissions ...) of your application.
Generate the Visual Guard configuration files by using the Visual Guard console. These configuration files will be needed to connect your application to the repository.
Grant read/write permissions to the repository.

Referencing Visual Guard assemblies

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

Opens the solution of your project in Visual Studio.
In the solution explorer, expands the project node.
Right-click the project node for the project and select Add Reference from the shortcut menu.
In .Net tab, select the 3 assemblies named Novalys.VisualGuard.Security, Novalys.VisualGuard.Security.WebFrom, Novalys.VisualGuard.Security.<RepositoryType> (File, SQLServer or Oracle), then click the Select button, and then click the OK button

Note: If the assemblies does not appear in this list you can use the Browse button and select them in the directory <Visual Guard installation directory>/bin/1.1.

Description of Visual Guard assemblies:

Novalys.VisualGuard.Security contains the main Visual Guard classes.
Novalys.VisualGuard.Security.Files contains the classes needed to access to a file based repository.
Novalys.VisualGuard.Security.SQLServer contains the classes needed to access to a repository stored in a Microsoft SQLServer database (SQLServer 2000 or higher). Available only in Visual Guard Enterprise Edition
Novalys.VisualGuard.Security.Oracle contains the classes needed to access to a repository stored in an Oracle database (8i or higher). Available only in Visual Guard Enterprise Edition
Novalys.VisualGuard.Security.WinForm contains all classes based on WinForm control. This assembly is needed only if you use the forms provided by Visual Guard to authenticate, change a password or select a role. If you want to use your own form you do not need to add a reference to this assembly.
Novalys.VisualGuard.Security.WebForm contains the classes needed to ASP.Net application. You must reference this assembly in ASP.Net WebSite or ASP.Net WebService project.

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 in the list of HttpModules in the "web.config" of your application. To do that, you must:

Open the "web.config" file of your application or add a new one to your project.
Add the following line of code in the <HttpModules> node.

<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 the 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 access to all pages in your web site.

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

To enable anonymous session, you must:

Open the Visual Guard console and connect to the repository associated to your application.
Create a new role in your application with a permission set containing permissions for an anonymous user.
Create a new user and grant the new role to this user
Select the item corresponding to your application and, in the property "Anonymous user", select the user created above.

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.

Integrating Visual Guard in your code

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

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)
{
    // 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.";
    }
    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
    ' 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."
    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 a custom class

If you need to secure only Page class in your application, you do not need to add more code. Visual Guard can detect automatically all page creations and apply the security action automatically. But, if you want to secure other types of class (WebControl, UserControl, non graphic class, etc), you must do the following:

Add the Novalys.VisualGuard.Security.VGISecurable interface to your class.
Add the call to the VGSecurityManager.SetSecurity method at the end of the constructor.

How to filter granted roles

If a user has more than one role, by default, Visual Guard creates a permission sets 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; 
      }
    } 
}

Granting Read/Write permission to the Repository

Visual Guard needs to Read/Write permissions to access to 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 database based repository, the user used to access to the Visual Guard repository database must be a member of "vg_BasicAccess" role.

In most of case, 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: