Message Security Anonymous

The Message Security Anonymous sample demonstrates how to implement a Windows Communication Foundation (WCF) application that uses message-level security with no client authentication but that requires server authentication using the server's X.509 certificate. All application messages between the client and server are signed and encrypted. This sample is based on the WSHttpBinding sample. This sample consists of a client console program (.exe) and a service library (.dll) hosted by Internet Information Services (IIS). The service implements a contract that defines a request-reply communication pattern.

This sample adds a new operation to the calculator interface that returns True if the client was not authenticated.

public class CalculatorService : ICalculator
{
    public bool IsCallerAnonymous()
    {
        // ServiceSecurityContext.IsAnonymous returns true if the caller is not authenticated.
        return ServiceSecurityContext.Current.IsAnonymous;
    }
    ...
}

The service exposes a single endpoint for communicating with the service, defined using a configuration file (Web.config). The endpoint consists of an address, a binding, and a contract. The binding is configured with a wsHttpBinding binding. The default security mode for the wsHttpBinding binding is Message. The clientCredentialType attribute is set to None.

<system.serviceModel>

  <protocolMapping>
    <add scheme="http" binding="wsHttpBinding" />
  </protocolMapping>

  <bindings>
    <wsHttpBinding>
     <!-- 
     <!--This configuration defines the security mode as Message and-->
     <!--the clientCredentialType as None. This mode provides -- >
     <!--server authentication only using the service certificate.-->
      
     <binding>
       <security mode="Message">
         <message clientCredentialType="None" />
       </security>
     </binding>
    </wsHttpBinding>
  </bindings>
  ...
</system.serviceModel>

The credentials to be used for service authentication are specified in the behavior Element. The server certificate must contain the same value for the SubjectName as the value specified for the findValue attribute as shown in the following sample code.

<behaviors>
  <serviceBehaviors>
    <behavior>
      <!-- 
    The serviceCredentials behavior allows you to define a service certificate.
    A service certificate is used by a client to authenticate the service and provide message protection.
    This configuration references the "localhost" certificate installed during the setup instructions.
    -->
      <serviceCredentials>
        <serviceCertificate findValue="localhost" storeLocation="LocalMachine" storeName="My" x509FindType="FindBySubjectName" />
      </serviceCredentials>
      <serviceMetadata httpGetEnabled="True"/>
      <serviceDebug includeExceptionDetailInFaults="False" />
    </behavior>
  </serviceBehaviors>
</behaviors>

The client endpoint configuration consists of an absolute address for the service endpoint, the binding, and the contract. The client security mode for the wsHttpBinding binding is Message. The clientCredentialType attribute is set to None.

<system.serviceModel>
  <client>
    <endpoint name=""
             address="https://localhost/servicemodelsamples/service.svc" 
             binding="wsHttpBinding" 
             behaviorConfiguration="ClientCredentialsBehavior"
             bindingConfiguration="Binding1" 
             contract="Microsoft.ServiceModel.Samples.ICalculator" />
  </client>

  <bindings>
    <wsHttpBinding>
      <!--This configuration defines the security mode as -->
      <!--Message and the clientCredentialType as None. -->
      <binding name="Binding1">
        <security mode = "Message">
          <message clientCredentialType="None"/>
        </security>
      </binding>
    </wsHttpBinding>
  </bindings> 
  ...
</system.serviceModel>

The sample sets the CertificateValidationMode to PeerOrChainTrust for authenticating the service's certificate. This is done in the client's App.config file in the behaviors section. This means that if the certificate is in the user's Trusted People store, then it is trusted without performing a validation of the certificate's issuer chain. This setting is used here for convenience so that the sample can be run without requiring certificates issued by a certificate authority (CA). This setting is less secure than the default, ChainTrust. The security implications of this setting should be carefully considered before using PeerOrChainTrust in production code.

The client implementation adds a call to the IsCallerAnonymous method and otherwise does not differ from the WSHttpBinding sample.

// Create a client with a client endpoint configuration.
CalculatorClient client = new CalculatorClient();

// Call the GetCallerIdentity operation.
Console.WriteLine("IsCallerAnonymous returned: {0}", client.IsCallerAnonymous());

// Call the Add service operation.
double value1 = 100.00D;
double value2 = 15.99D;
double result = client.Add(value1, value2);
Console.WriteLine("Add({0},{1}) = {2}", value1, value2, result);

...

//Closing the client gracefully closes the connection and cleans up resources.
client.Close();

Console.WriteLine();
Console.WriteLine("Press <ENTER> to terminate client.");
Console.ReadLine();
 

When you run the sample, the operation requests and responses are displayed in the client console window. Press ENTER in the client window to shut down the client.

IsCallerAnonymous returned: True
Add(100,15.99) = 115.99
Subtract(145,76.54) = 68.46
Multiply(9,81.25) = 731.25
Divide(22,7) = 3.14285714285714
Press <ENTER> to terminate client.

The Setup.bat batch file included with the Message Security Anonymous sample enables you to configure the server with a relevant certificate to run a hosted application that requires certificate-based security. The batch file can be run in two modes. To run the batch file in the single-computer mode, type setup.bat at the command line. To run it in service mode, type setup.bat service. Use this mode when running the sample across computers. See the setup procedure at the end of this topic for details.

The following provides a brief overview of the different sections of the batch files:

• Creating the server certificate.

  The following lines from the Setup.bat batch file create the server certificate to be used.

  echo ************
  echo Server cert setup starting
  echo %SERVER_NAME%
  echo ************
  echo making server cert
  echo ************
  makecert.exe -sr LocalMachine -ss MY -a sha1 -n CN=%SERVER_NAME% -sky exchange -pe
  

  The %SERVER_NAME% variable specifies the server name. The certificate is stored in the LocalMachine store. If the setup batch file is run with an argument of service (such as setup.bat service) the %SERVER_NAME% contains the fully-qualified domain name of the computer. Otherwise it defaults to localhost.

• Installing the server certificate into the client's trusted certificate store.

  The following line copies the server certificate into the client trusted people store. This step is required because certificates generated by Makecert.exe are not implicitly trusted by the client system. If you already have a certificate that is rooted in a client trusted root certificate—for example, a Microsoft-issued certificate—this step of populating the client certificate store with the server certificate is not required.

  certmgr.exe -add -r LocalMachine -s My -c -n %SERVER_NAME% -r CurrentUser -s TrustedPeople
  

• Granting permissions on the certificate's private key.

  The following lines in the Setup.bat batch file make the server certificate stored in the LocalMachine store accessible to the ASP.NET worker process account.

  echo ************
  echo setting privileges on server certificates
  echo ************
  for /F "delims=" %%i in ('"%MSSDK%\bin\FindPrivateKey.exe" My LocalMachine -n CN^=%SERVER_NAME% -a') do set PRIVATE_KEY_FILE=%%i set WP_ACCOUNT=NT AUTHORITY\NETWORK SERVICE
  (ver | findstr "5.1") && set WP_ACCOUNT=%COMPUTERNAME%\ASPNET
  echo Y|cacls.exe "%PRIVATE_KEY_FILE%" /E /G "%WP_ACCOUNT%":R
  iisreset
  

To set up, build, and run the sample

1. Ensure that you have performed the One-Time Setup Procedure for the Windows Communication Foundation Samples.

2. To build the C# or Visual Basic .NET edition of the solution, follow the instructions in Building the Windows Communication Foundation Samples.

To run the sample on the same computer

1. Ensure that the path includes the folder where Makecert.exe and FindPrivateKey.exe are located.

2. Run Setup.bat from the sample install folder in a Visual Studio command prompt run with administrator privileges. This installs all the certificates required for running the sample.

   Note

   The setup batch file is designed to be run from a Visual Studio 2010 Command Prompt. It requires that the path environment variable point to the directory where the SDK is installed. This environment variable is automatically set within a Visual Studio 2010 Command Prompt.

3. Verify access to the service using a browser by entering the address https://localhost/servicemodelsamples/service.svc.

4. Launch Client.exe from \client\bin. Client activity is displayed on the client console application.

5. If the client and service are not able to communicate, see Troubleshooting Tips.

To run the sample across computers

1. Create a directory on the service computer. Create a virtual application named servicemodelsamples for this directory by using the Internet Information Services (IIS) management tool.

2. Copy the service program files from \inetpub\wwwroot\servicemodelsamples to the virtual directory on the service computer. Ensure that you copy the files in the \bin subdirectory. Also copy the Setup.bat and Cleanup.bat files to the service computer.

3. Create a directory on the client computer for the client binaries.

4. Copy the client program files to the client directory on the client computer. Also copy the Setup.bat, Cleanup.bat, and ImportServiceCert.bat files to the client.

5. On the server, run setup.bat service in a Visual Studio command prompt opened with administrator privileges. Running setup.bat with the service argument creates a service certificate with the fully-qualified domain name of the computer and exports the service certificate to a file named Service.cer.

6. Edit Web.config to reflect the new certificate name (in the findValue attribute in the serviceCertificate element of serviceCredentials), which is the same as the fully-qualified domain name of the computer.

7. Copy the Service.cer file from the service directory to the client directory on the client computer.

8. In the Client.exe.config file on the client computer, change the address value of the endpoint to match the new address of your service.

9. On the client, run ImportServiceCert.bat in a Visual Studio command prompt opened with administrator privileges. This imports the service certificate from the Service.cer file into the CurrentUser - TrustedPeople store.

10. On the client computer, launch Client.exe from a command prompt. If the client and service are not able to communicate, see Troubleshooting Tips.

To clean up after the sample

• Run Cleanup.bat in the samples folder after you have finished running the sample.