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Remplacement d'un objet Principal

  • Article

Les applications qui fournissent des services d’authentification doivent pouvoir remplacer l’objet Principal (IPrincipal) d’un thread donné. En outre, le système de sécurité doit permettre de protéger la possibilité de remplacer les objets Principal si un Principal malveillant et incorrect attaché compromet la sécurité de votre application en simulant une fausse identité ou un faux rôle. Par conséquent, les applications ayant besoin de pouvoir remplacer les objets Principal doivent se voir attribuer l’objet System.Security.Permissions.SecurityPermission pour le contrôle du principal. (Notez que cette autorisation n’est pas obligatoire pour effectuer des vérifications de sécurité basée sur les rôles ou créer des objets Principal .)

L’objet Principal actuel peut être remplacé en effectuant les tâches suivantes :

  1. Créer l’objet Principal de remplacement et l’objet Identity associé.

  2. Attacher le nouvel objet Principal au contexte d’appel.

Exemple

L’exemple suivant montre comment créer un objet principal générique et l’utiliser pour définir le principal d’un thread.

using System;
using System.Threading;
using System.Security.Permissions;
using System.Security.Principal;

class SecurityPrincipalDemo
{
    public static void Main()
    {
        // Retrieve a GenericPrincipal that is based on the current user's
        // WindowsIdentity.
        GenericPrincipal genericPrincipal = GetGenericPrincipal();

        // Retrieve the generic identity of the GenericPrincipal object.
        GenericIdentity principalIdentity =
            (GenericIdentity)genericPrincipal.Identity;

        // Display the identity name and authentication type.
        if (principalIdentity.IsAuthenticated)
        {
            Console.WriteLine(principalIdentity.Name);
            Console.WriteLine("Type:" + principalIdentity.AuthenticationType);
        }

        // Verify that the generic principal has been assigned the
        // NetworkUser role.
        if (genericPrincipal.IsInRole("NetworkUser"))
        {
            Console.WriteLine("User belongs to the NetworkUser role.");
        }

        Thread.CurrentPrincipal = genericPrincipal;
    }

    // Create a generic principal based on values from the current
    // WindowsIdentity.
    private static GenericPrincipal GetGenericPrincipal()
    {
        // Use values from the current WindowsIdentity to construct
        // a set of GenericPrincipal roles.
        WindowsIdentity windowsIdentity = WindowsIdentity.GetCurrent();
        string[] roles = new string[10];
        if (windowsIdentity.IsAuthenticated)
        {
            // Add custom NetworkUser role.
            roles[0] = "NetworkUser";
        }

        if (windowsIdentity.IsGuest)
        {
            // Add custom GuestUser role.
            roles[1] = "GuestUser";
        }

        if (windowsIdentity.IsSystem)
        {
            // Add custom SystemUser role.
            roles[2] = "SystemUser";
        }

        // Construct a GenericIdentity object based on the current Windows
        // identity name and authentication type.
        string authenticationType = windowsIdentity.AuthenticationType!;
        string userName = windowsIdentity.Name;
        GenericIdentity genericIdentity =
            new GenericIdentity(userName, authenticationType);

        // Construct a GenericPrincipal object based on the generic identity
        // and custom roles for the user.
        GenericPrincipal genericPrincipal =
            new GenericPrincipal(genericIdentity, roles);

        return genericPrincipal;
    }
}

Imports System.Threading
Imports System.Security.Permissions
Imports System.Security.Principal



Class SecurityPrincipalDemo

    ' Create a generic principal based on values from the current
    ' WindowsIdentity.
    Private Shared Function GetGenericPrincipal() As GenericPrincipal
        ' Use values from the current WindowsIdentity to construct
        ' a set of GenericPrincipal roles.
        Dim windowsIdentity As WindowsIdentity = windowsIdentity.GetCurrent()
        Dim roles(9) As String
        If windowsIdentity.IsAuthenticated Then
            ' Add custom NetworkUser role.
            roles(0) = "NetworkUser"
        End If

        If windowsIdentity.IsGuest Then
            ' Add custom GuestUser role.
            roles(1) = "GuestUser"
        End If

        If windowsIdentity.IsSystem Then
            ' Add custom SystemUser role.
            roles(2) = "SystemUser"
        End If

        ' Construct a GenericIdentity object based on the current Windows
        ' identity name and authentication type.
        Dim authenticationType As String = windowsIdentity.AuthenticationType
        Dim userName As String = windowsIdentity.Name
        Dim genericIdentity As New GenericIdentity(userName, authenticationType)

        ' Construct a GenericPrincipal object based on the generic identity
        ' and custom roles for the user.
        Dim genericPrincipal As New GenericPrincipal(genericIdentity, roles)

        Return genericPrincipal

    End Function 'GetGenericPrincipal

    Public Shared Sub Main()
        ' Retrieve a GenericPrincipal that is based on the current user's
        ' WindowsIdentity.
        Dim genericPrincipal As GenericPrincipal = GetGenericPrincipal()

        ' Retrieve the generic identity of the GenericPrincipal object.
        Dim principalIdentity As GenericIdentity = CType(genericPrincipal.Identity, GenericIdentity)

        ' Display the identity name and authentication type.
        If principalIdentity.IsAuthenticated Then
            Console.WriteLine(principalIdentity.Name)
            Console.WriteLine("Type:" + principalIdentity.AuthenticationType)
        End If

        ' Verify that the generic principal has been assigned the
        ' NetworkUser role.
        If genericPrincipal.IsInRole("NetworkUser") Then
            Console.WriteLine("User belongs to the NetworkUser role.")
        End If

        Thread.CurrentPrincipal = genericPrincipal

    End Sub



End Class

Voir aussi