Skip to main content

ASMX services and Self-Signed Certificates

When you try to call a web service that uses a self-signed certificate from a client application you get the following error:
The underlying connection was closed: Could not establish trust relationship for the SSL/TLS secure channel.

This is because your system marks the certificate as invalid. There are 3 tests that must be checked before a certificate is marked as valid:

  1. The certificate must be issued by a trusted certification authority.
  2. The certificate is not outdated.
  3. The hostname must match the certificate subject.

If one of those three tests return false then the certificate is marked as invalid. When you are just testing your application, you can make your client proxy ignore these tests and just call the service.

Therefore create a class file that contains the following code:

 

   1:  using System.Net.Security;
   2:  using System.Security.Cryptography.X509Certificates;
   3:   
   4:       class Certificates
   5:       {
   6:            public static bool ValidateRemoteCertificate(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors policyErrors)
   7:            {
   8:                 //Return True to force the certificate to be accepted.      
   9:                 //Needed so that calling web services with self-signed certs will work.
  10:                 return true;
  11:            }
  12:        }
  13:   

Afterwards add the following lines to the Application_BeginRequest event in the global.asax file or the OnInit event of any page that needs to call a web services that uses a self-signed certificate. 

 

   1:  using System; 
   2:  using System.Net; 
   3:  using System.Net.Security; 
   4:   
   5:       protected void Application_BeginRequest(Object sender, EventArgs e) 
   6:       { 
   7:             ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(Certificates.ValidateRemoteCertificate); 
   8:       }

Of course, ignoring the certificate errors within the code could open up a security risk depending on what it is being used for.

Labels:

Popular posts from this blog

Podman– Command execution failed with exit code 125

After updating WSL on one of the developer machines, Podman failed to work. When we took a look through Podman Desktop, we noticed that Podman had stopped running and returned the following error message: Error: Command execution failed with exit code 125 Here are the steps we tried to fix the issue: We started by running podman info to get some extra details on what could be wrong: >podman info OS: windows/amd64 provider: wsl version: 5.3.1 Cannot connect to Podman. Please verify your connection to the Linux system using `podman system connection list`, or try `podman machine init` and `podman machine start` to manage a new Linux VM Error: unable to connect to Podman socket: failed to connect: dial tcp 127.0.0.1:2655: connectex: No connection could be made because the target machine actively refused it. That makes sense as the podman VM was not running. Let’s check the VM: >podman machine list NAME         ...
Read more

Azure DevOps/ GitHub emoji

I’m really bad at remembering emoji’s. So here is cheat sheet with all emoji’s that can be used in tools that support the github emoji markdown markup: All credits go to rcaviers who created this list.
Read more

VS Code Planning mode

After the introduction of Plan mode in Visual Studio , it now also found its way into VS Code. Planning mode, or as I like to call it 'Hannibal mode', extends GitHub Copilot's Agent Mode capabilities to handle larger, multi-step coding tasks with a structured approach. Instead of jumping straight into code generation, Planning mode creates a detailed execution plan. If you want more details, have a look at my previous post . Putting plan mode into action VS Code takes a different approach compared to Visual Studio when using plan mode. Instead of a configuration setting that you can activate but have limited control over, planning is available as a separate chat mode/agent: I like this approach better than how Visual Studio does it as you have explicit control when plan mode is activated. Instead of immediately diving into execution, the plan agent creates a plan and asks some follow up questions: You can further edit the plan by clicking on ‘Open in Editor’: ...
Read more