How to: Create a Custom Security Token Provider
This topic shows how to create new token types with a custom security token provider and how to integrate the provider with a custom security token manager.
Note
Create a custom token provider if the system-provided tokens found in the System.IdentityModel.Tokens namespace do not match your requirements.
The security token provider creates a security token representation based on information in the client or service credentials. To use the custom security token provider in Windows Communication Foundation (WCF) security, you must create custom credentials and security token manager implementations.
For more information about custom credentials and security token manager see the Walkthrough: Creating Custom Client and Service Credentials.
To create a custom security token provider
Define a new class derived from the SecurityTokenProvider class.
Implement the GetTokenCore(TimeSpan) method. The method is responsible for creating and returning an instance of the security token. The following example creates a class named
MySecurityTokenProvider
, and overrides the GetTokenCore(TimeSpan) method to return an instance of the X509SecurityToken class. The class constructor requires an instance of the X509Certificate2 class.internal class MySecurityTokenProvider : SecurityTokenProvider { X509Certificate2 certificate; public MySecurityTokenProvider(X509Certificate2 certificate) { this.certificate = certificate; } protected override SecurityToken GetTokenCore(TimeSpan timeout) { return new X509SecurityToken(certificate); } }
Friend Class MySecurityTokenProvider Inherits SecurityTokenProvider Private certificate As X509Certificate2 Public Sub New(ByVal certificate As X509Certificate2) Me.certificate = certificate End Sub Protected Overrides Function GetTokenCore(ByVal timeout As TimeSpan) As SecurityToken Return New X509SecurityToken(certificate) End Function End Class
To integrate a custom security token provider with a custom security token manager
Define a new class derived from the SecurityTokenManager class. (The example below derives from the ClientCredentialsSecurityTokenManager class, which derives from the SecurityTokenManager class.)
Override the CreateSecurityTokenProvider(SecurityTokenRequirement) method if is not already overridden.
The CreateSecurityTokenProvider(SecurityTokenRequirement) method is responsible for returning an instance of the SecurityTokenProvider class appropriate to the SecurityTokenRequirement parameter passed to the method by the WCF security framework. Modify the method to return the custom security token provider implementation (created in the previous procedure) when the method is called with an appropriate security token parameter. For more information about the security token manager, see the Walkthrough: Creating Custom Client and Service Credentials.
Add custom logic to the method to enable it to return your custom security token provider based on the SecurityTokenRequirement parameter. The following sample returns the custom security token provider if the token requirements are met. The requirements include an X.509 security token and the message direction (that the token is used for message output). For all other cases, the code calls the base class to maintain the system-provided behavior for other security token requirements.
internal class MyClientCredentialsSecurityTokenManager:ClientCredentialsSecurityTokenManager
{
ClientCredentials credentials;
public MyClientCredentialsSecurityTokenManager(ClientCredentials credentials)
: base(credentials)
{
this.credentials = credentials;
}
public override SecurityTokenProvider CreateSecurityTokenProvider(
SecurityTokenRequirement tokenRequirement)
{
// Return your implementation of the SecurityTokenProvider based on the
// tokenRequirement argument.
SecurityTokenProvider result;
if (tokenRequirement.TokenType == SecurityTokenTypes.X509Certificate)
{
MessageDirection direction = tokenRequirement.GetProperty<MessageDirection>(
ServiceModelSecurityTokenRequirement.MessageDirectionProperty);
if (direction == MessageDirection.Output)
{
result = new MySecurityTokenProvider(credentials.ClientCertificate.Certificate);
}
else
{
result = base.CreateSecurityTokenProvider(tokenRequirement);
}
}
else
{
result = base.CreateSecurityTokenProvider(tokenRequirement);
}
return result;
}
}
Friend Class MyClientCredentialsSecurityTokenManager
Inherits ClientCredentialsSecurityTokenManager
Private credentials As ClientCredentials
Public Sub New(ByVal credentials As ClientCredentials)
MyBase.New(credentials)
Me.credentials = credentials
End Sub
Public Overrides Function CreateSecurityTokenProvider(ByVal tokenRequirement As SecurityTokenRequirement) As SecurityTokenProvider
' Return your implementation of the SecurityTokenProvider based on the
' tokenRequirement argument.
Dim result As SecurityTokenProvider
If tokenRequirement.TokenType = SecurityTokenTypes.X509Certificate Then
Dim direction As MessageDirection = tokenRequirement.GetProperty(Of MessageDirection) _
(ServiceModelSecurityTokenRequirement.MessageDirectionProperty)
If direction = MessageDirection.Output Then
result = New MySecurityTokenProvider(credentials.ClientCertificate.Certificate)
Else
result = MyBase.CreateSecurityTokenProvider(tokenRequirement)
End If
Else
result = MyBase.CreateSecurityTokenProvider(tokenRequirement)
End If
Return result
End Function
End Class
Example
The following shows a complete SecurityTokenProvider implementation along with a corresponding SecurityTokenManager implementation.
using System;
using System.IdentityModel.Selectors;
using System.IdentityModel.Tokens;
using System.Security.Cryptography.X509Certificates;
using System.ServiceModel;
using System.ServiceModel.Description;
using System.ServiceModel.Security.Tokens;
namespace CustomProvider
{
internal class MySecurityTokenProvider : SecurityTokenProvider
{
X509Certificate2 certificate;
public MySecurityTokenProvider(X509Certificate2 certificate)
{
this.certificate = certificate;
}
protected override SecurityToken GetTokenCore(TimeSpan timeout)
{
return new X509SecurityToken(certificate);
}
}
internal class MyClientCredentialsSecurityTokenManager:ClientCredentialsSecurityTokenManager
{
ClientCredentials credentials;
public MyClientCredentialsSecurityTokenManager(ClientCredentials credentials)
: base(credentials)
{
this.credentials = credentials;
}
public override SecurityTokenProvider CreateSecurityTokenProvider(
SecurityTokenRequirement tokenRequirement)
{
// Return your implementation of the SecurityTokenProvider based on the
// tokenRequirement argument.
SecurityTokenProvider result;
if (tokenRequirement.TokenType == SecurityTokenTypes.X509Certificate)
{
MessageDirection direction = tokenRequirement.GetProperty<MessageDirection>(
ServiceModelSecurityTokenRequirement.MessageDirectionProperty);
if (direction == MessageDirection.Output)
{
result = new MySecurityTokenProvider(credentials.ClientCertificate.Certificate);
}
else
{
result = base.CreateSecurityTokenProvider(tokenRequirement);
}
}
else
{
result = base.CreateSecurityTokenProvider(tokenRequirement);
}
return result;
}
}
}
Imports System.IdentityModel.Selectors
Imports System.IdentityModel.Tokens
Imports System.Security.Permissions
Imports System.Security.Cryptography.X509Certificates
Imports System.ServiceModel
Imports System.ServiceModel.Description
Imports System.ServiceModel.Security.Tokens
Friend Class MySecurityTokenProvider
Inherits SecurityTokenProvider
Private certificate As X509Certificate2
Public Sub New(ByVal certificate As X509Certificate2)
Me.certificate = certificate
End Sub
Protected Overrides Function GetTokenCore(ByVal timeout As TimeSpan) As SecurityToken
Return New X509SecurityToken(certificate)
End Function
End Class
Friend Class MyClientCredentialsSecurityTokenManager
Inherits ClientCredentialsSecurityTokenManager
Private credentials As ClientCredentials
Public Sub New(ByVal credentials As ClientCredentials)
MyBase.New(credentials)
Me.credentials = credentials
End Sub
Public Overrides Function CreateSecurityTokenProvider(ByVal tokenRequirement As SecurityTokenRequirement) As SecurityTokenProvider
' Return your implementation of the SecurityTokenProvider based on the
' tokenRequirement argument.
Dim result As SecurityTokenProvider
If tokenRequirement.TokenType = SecurityTokenTypes.X509Certificate Then
Dim direction As MessageDirection = tokenRequirement.GetProperty(Of MessageDirection) _
(ServiceModelSecurityTokenRequirement.MessageDirectionProperty)
If direction = MessageDirection.Output Then
result = New MySecurityTokenProvider(credentials.ClientCertificate.Certificate)
Else
result = MyBase.CreateSecurityTokenProvider(tokenRequirement)
End If
Else
result = MyBase.CreateSecurityTokenProvider(tokenRequirement)
End If
Return result
End Function
End Class