WCF: Matching a specific WS-Security scheme (Signature, Encrypt, UserPass) - asp.net

Question

I'm trying to match a specific WS-Security specification from a vendor. The following works in SOAP UI, which I am now trying to recreate in C# WCF (targeting .NET 4.7.2 or 4.8):
Username/Password element
Timestamp: 9000ms
Signature (cert A):
Sign with certificate
Prepend signature element
Sign timestamp and username token
Encryption (cert B):
Create encrypted key
Encrypt body, timestamp, and username token
Everything I've tried so far seems to encrypt everything in the WS-Security header except for the timestamp.
References followed:
WCF - Separate x509 for Signing and Encryption
SOAP UI Setup - Signature:
SOAP UI Setup - Encryption:

Answer 1

You can try to use IClientMessageInspectortor add a header to the message. In the BeforeSendRequest method, you can add a custom header to the outgoing message.Here is a demo:
public class CustomMessageInspector : IClientMessageInspector
{
public void AfterReceiveReply(ref Message reply, object correlationState)
{
return;
}
public object BeforeSendRequest(ref Message request, IClientChannel channel)
{
MessageHeader header = MessageHeader.CreateHeader("Testreply", "http://Test", "Test");
request.Headers.Add(header);
return null;
}
}
[AttributeUsage(AttributeTargets.Interface)]
public class CustContractBehaviorAttribute : Attribute, IContractBehavior
{
public void AddBindingParameters(ContractDescription contractDescription, ServiceEndpoint endpoint, BindingParameterCollection bindingParameters)
{
return;
}
public void ApplyClientBehavior(ContractDescription contractDescription, ServiceEndpoint endpoint, ClientRuntime clientRuntime)
{
clientRuntime.ClientMessageInspectors.Add(new CustomMessageInspector());
}
public void ApplyDispatchBehavior(ContractDescription contractDescription, ServiceEndpoint endpoint, DispatchRuntime dispatchRuntime)
{
return;
}
public void Validate(ContractDescription contractDescription, ServiceEndpoint endpoint)
{
return;
}
}
Add CustContractBehaviorAttribute to apply it: