Adding a nonce for integrity in consumer security constraints with an XPath expression

 

Before you begin

Prior to completing this task, import your application into an assembly tool. For information on how to import your application, see Import enterprise applications.

The following information explains the difference between using an XPath expression and using keywords to specify which part of the message to sign:

XPath expression

Specify any part of the message using an XPath expression. XPath is a language that is used to address parts of an XML document. We can find information on XPath syntax at the following Web site: http://www.w3.org/TR/1999/REC-xpath-19991116.

Keywords

Specify only elements within the message using predefined keywords.

 

Overview

Nonce for integrity is used to specify that a nonce is embedded in a particular element within the message and that the element is signed. Complete the following steps to specify a nonce for integrity using an XPath expression when you configure the consumer security constraints for either the response consumer or the request consumer. The response consumer is configured for the client and the request consumer is configured for the server. In the following steps, configure either the client-side bindings in step 2 or the server-side bindings in step 3.

 

Procedure

1. Start the assembly tool and click Window > Open Perspective > J2EE.

2. Optional: Locate the client-side bindings using the Project Explorer window. The Client Deployment Descriptor window is displayed. This Web service contains the extensions that we need to configure. Complete the following steps to locate the client-side bindings:

   1. Expand the Web Services > Client section and double-click the name of the Web service.

   2. Click the WS Extension tab and expand the Response Consumer Configuration section.

3. Optional: Locate the server-side bindings using the Project Explorer window. The Web Services Editor window is displayed. This Web service contains the bindings that we need to configure. Complete the following steps to locate the server-side bindings:

   1. Expand the Web Services > Services section and double-click the name of the Web service.

   2. Click the Extensions tab and expand the Request Consumer Service Configuration Details section.

4. Expand the Required Integrity section. Integrity refers to digital signature while confidentiality refers to encryption. Integrity decreases the risk of data modification when you transmit data across a network. For more information on digitally signing SOAP messages, see XML digital signature.

5. Click Add to specify a nonce for integrity. The Required Integrity Dialog window is displayed. Complete the following steps to specify a configuration:

   1. Specify a name for the integrity element in the Required Integrity Name field.

   2. Specify a usage type in the Usage type field. This field specifies the requirement for the integrity element. The value of this attribute is either Required or Optional.

6. Click Add in the Nonce section of the Required Integrity Dialog window. Complete the following steps to configure the nonce dialect and message part:

   1. Select the Nonce dialect from the Nonce section. The http://www.w3.org/TR/1999/REC-xpath-19991116 dialect specifies the message part to which a nonce is added and signed using an XPath expression.

   2. Select the message part in the Nonce keyword field to which a nonce is added and signed using an XPath expression. For example, to specify that a nonce is added to the body and that it is signed, you might specify the following expression for the Nonce keyword

      /*[namespace-uri()='http://schemas.xmlsoap.org/soap/envelope/' 
      and local-name()='Envelope']/*[namespace-uri()='http://schemas.xmlsoap.org/
      soap/envelope/' and local-name()='Body']
      

7. In the Message Parts section, click Add and select http://www.w3.org/TR/1999/REC-xpath-19991116 in the Message parts dialect field.

8. In the Message Parts section, select the message parts keyword. Important: You must select the same keyword in the Message parts keyword field as the keyword that you selected in the Nonce keyword field.

9. Click OK to save the configuration changes.

   Note: These configurations on the consumer side and the generator side must match.

   In addition to the nonce, one can specify that the timestamp element is signed. For more information, see the following articles:

   • Adding time stamps for integrity in consumer security constraints with keywords

   • Adding time stamps for integrity in consumer security constraints with an XPath expression

 

What to do next

After you specify which message parts to digitally sign, specify which method is used to digitally sign the message. For more information, see Configuring signing information for the consumer binding with an assembly tool.

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See Also

XML digital signature

 

Related Tasks

Adding a stand-alone time stamp in consumer security constraints
Adding time stamps for integrity in consumer security constraints with keywords
Adding time stamps for integrity in consumer security constraints with an XPath expression
Adding a nonce for integrity in consumer security constraints with keywords
Configuring signing information for the consumer binding with an assembly tool

 

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