MachineKeySection Class (System.Web.Configuration) (2024)

Definition

public ref class MachineKeySection sealed : System::Configuration::ConfigurationSection

public sealed class MachineKeySection : System.Configuration.ConfigurationSection

type MachineKeySection = class inherit ConfigurationSection

Public NotInheritable Class MachineKeySectionInherits ConfigurationSection

Inheritance

Object

See Also

What is the RSA algorithm? Definition from SearchSecurity

ConfigurationElement

ConfigurationSection

MachineKeySection

Examples

The example in this section demonstrates how to specify values declaratively for several attributes of the machineKey section, which can also be accessed as members of the MachineKeySection class.

The following example from a configuration file shows how to specify values declaratively for the machineKey section.

<system.web> <machineKey validationKey="AutoGenerate,IsolateApps" decryptionKey="AutoGenerate,IsolateApps" validation="SHA1"/> </system.web> 

This example uses SHA1. Due to collision problems with SHA1, Microsoft recommends SHA256.

The following example demonstrates how to use the MachineKeySection class in code.

#region Using directivesusing System;using System.Collections.Generic;using System.Text;using System.Configuration;using System.Web;using System.Web.Configuration;#endregionnamespace Samples.Aspnet.SystemWebConfiguration{ class UsingMachineKeySection { static void Main(string[] args) { try { // Set the path of the config file. string configPath = ""; // Get the Web application configuration object. Configuration config = WebConfigurationManager.OpenWebConfiguration(configPath); // Get the section related object. MachineKeySection configSection = (MachineKeySection)config.GetSection("system.web/machineKey"); // Display title and info. Console.WriteLine("ASP.NET Configuration Info"); Console.WriteLine(); // Display Config details. Console.WriteLine("File Path: {0}", config.FilePath); Console.WriteLine("Section Path: {0}", configSection.SectionInformation.Name); // Display ValidationKey property. Console.WriteLine("ValidationKey: {0}", configSection.ValidationKey); // Set ValidationKey property. configSection.ValidationKey = "AutoGenerate,IsolateApps"; // Display DecryptionKey property. Console.WriteLine("DecryptionKey: {0}", configSection.DecryptionKey); // Set DecryptionKey property. configSection.DecryptionKey = "AutoGenerate,IsolateApps"; // Display Validation property. Console.WriteLine("Validation: {0}", configSection.Validation); // Set Validation property. configSection.Validation = MachineKeyValidation.HMACSHA256; // Update if not locked. if (!configSection.SectionInformation.IsLocked) { config.Save(); Console.WriteLine("** Configuration updated."); } else { Console.WriteLine("** Could not update, section is locked."); } } catch (Exception e) { // Unknown error. Console.WriteLine(e.ToString()); } // Display and wait Console.ReadLine(); } }}

Imports System.Collections.GenericImports System.TextImports System.ConfigurationImports System.WebImports System.Web.ConfigurationNamespace Samples.Aspnet.SystemWebConfiguration Class UsingMachineKeySection Public Shared Sub Main() Try ' Set the path of the config file. Dim configPath As String = "" ' Get the Web application configuration object. Dim config As System.Configuration.Configuration = _ System.Web.Configuration.WebConfigurationManager.OpenWebConfiguration(configPath) ' Get the section related object. Dim configSection As System.Web.Configuration.MachineKeySection = _ CType(config.GetSection("system.web/machineKey"), _ System.Web.Configuration.MachineKeySection) ' Display title and info. Console.WriteLine("ASP.NET Configuration Info") Console.WriteLine() ' Display Config details. Console.WriteLine("File Path: {0}", config.FilePath) Console.WriteLine("Section Path: {0}", configSection.SectionInformation.Name) ' Display ValidationKey property. Console.WriteLine("ValidationKey: {0}", _ configSection.ValidationKey) ' Set ValidationKey property. configSection.ValidationKey = "AutoGenerate,IsolateApps" ' Display DecryptionKey property. Console.WriteLine("DecryptionKey: {0}", configSection.DecryptionKey) ' Set DecryptionKey property. configSection.DecryptionKey = "AutoGenerate,IsolateApps" ' Display Validation value. Console.WriteLine("Validation: {0}", configSection.Validation) ' Set Validation value. configSection.Validation = MachineKeyValidation.HMACSHA256 ' Update if not locked. If Not configSection.SectionInformation.IsLocked Then config.Save() Console.WriteLine("** Configuration updated.") Else Console.WriteLine("** Could not update, section is locked.") End If Catch e As Exception ' Unknown error. Console.WriteLine(e.ToString()) End Try ' Display and wait Console.ReadLine() End Sub End ClassEnd Namespace

Remarks

The MachineKeySection class provides a way to programmatically access and modify the content of the MachineKey section in the configuration file. The MachineKey section can be configured at the machine (Machine.config) or application (Web.config) level and controls the keys and algorithms that are used for Windows Forms authentication, view-state validation, and session-state application isolation. For any of these features to work across a network of Web servers (a Web farm), the DecryptionKey and ValidationKey attributes of the MachineKey section must be configured explicitly and identically with valid key values. The AutoGenerate value does not work for Web farms, because it relies on a cryptographically random secret, which is persisted using machine-local protection and will not be the same across more than one computer.

Notes to Inheritors

If you to specify keys in this configuration section, as is required in Web-farm scenarios, it is recommended that you encrypt this section by using protected configuration.

Constructors

Properties

Methods

Applies to

See also

• ConfigurationSection
• Forms Authentication Credentials