Self signed client certificate does not reach server application - ssl

I have the following setup:
A self signed certificate for development purposes
An OWIN hosted Web API, deployed on a local Azure Service Fabric Cluster as a ASF service. The Web API uses HTTPS facilitated with the dev certificate in question.
A simple .net client application that calls the Web API. In that application the ServicePointManager.ServerCertificateValidationCallback method is set so it always returns true (since the CA is not trusted)
Both the client application and the Web API are on the same local development machine. The certificate is installed in that same machine on the "machine store"
Now I am able to make calls to the web api using Fiddler by providing the required client certificate. However when I try to do the same via .net code (be it RestSharp or WebRequest) the client certificate is not present in the RequestContext object on the server side. This result in an Unauthorized response. I do not think the problem is with the client code, the certificate is loaded correctly and assigned to the http client or request. Fiddler shows encrypted tunneling to the server. However the client certificate does not seem to be present at the server side.
I am at a complete loss regarding what am I missing that could cause this behavior. Any help will be deeply appreciated.

Install the certificate into the 'Local Machine/Trusted People'.

The server needs to already trust the certificate before it asks. The CertificateRequest message that it sends lists the acceptable CAs that can sign the client certificate. If the client certificate's signer isn't in that message, it can't send it.
How you accomplish that in your environment is left as an exercise for the reader. In general now that SSL certificates are available free there is little reason to indulge in the time costs and administrative inconveniences of self-signed certificates. IMHO there wasn't even if you were paying for a CA signature.

I had a problem when a service called another service over HTTPS and it couldn't setup a secure connection. My problem was that since the service is running as NETWORK SERVICE, it couldn't find the certificate, because it was looking in the localmachine/my certificate store.
When I was running from my web browser it was working fine because then, my browser found the certificate in the currectuser/my certificate store.
Add the certificate to the machine/my store and see if it helps.

Related

HTTPS communication in ServiceFabric Local Cluster

Here's my setup
an IdentityServer 4 as a stateless reliable ASP.NET Core service.
a WebAPI as a reliable ASP.NET Core service.
using them with a JS client, it is now working with HTTP. The problem is with HTTPS. The WebAPI needs to request the openID config via htttps [is4URL].well-known/openid-configuration. I'm getting this error
System.InvalidOperationException: IDX10803: Unable to obtain
configuration from:
'https://localhost:9999/.well-known/openid-configuration'. --->
System.IO.IOException: IDX10804: Unable to retrieve document from:
'https://localhost:9999/.well-known/openid-configuration'. --->
System.Net.Http.HttpRequestException: An error occurred while sending
the request. ---> System.Net.WebException: The underlying connection
was closed: Could not establish trust relationship for the SSL/TLS
secure channel. --->
System.Security.Authentication.AuthenticationException: The remote
certificate is invalid according to the validation procedure.
can anybody help me to make this work in localhost with the SF Local Cluster Manager?
Thanks
Here's my two cents worth but it will need to be verified...
I am assuming that you have created a self-signed certificate using following article or similar but the certificate has same properties.
https://learn.microsoft.com/en-us/azure/app-service-web/web-sites-configure-ssl-certificate
This means that the certificate can not be verified via actual CA. Ofcourse with self-signed certificate this is not possible.
Now when you upload the certificate to Azure App Service it installs in CurrentUser - MyStore. With self-signed certificate, it also needs to be installed in LocalMachine Root store.
This is becouse then the machine's Certificate Authority can verify that certificate to be valid. (May be a security expert can correct me if I am wrong but thats my theory). I have got same setup on my locally hosted windows server where the self-signed certificate is installed in Root Certificate Store as well as Personal store and the app works. This is the reason I belive this happens.
So this part which needs to be verified. Following is the article which shows you how you can do this in Azure App service.
https://learn.microsoft.com/en-us/azure/cloud-services/cloud-services-configure-ssl-certificate-portal
AGAIN THIS IS JUST A THEORY THIS NEEDS TO BE VERIFIED. :)
EDIT:
I have just tested this and it is the case. In cloud services you can do as shown in second link above and create Web Job which install certificate in appropriate store.
For Azure App Service unfortunaltly you dont have access to root store. It has to be install in CurrentUser's personal store. Which means the self signed certificate will not work, and you have to purchase a real certificate. :( I think this is a real thumb down to Microsoft. Why should I need to pay for real certificate for my dev/test environment? (Rant Over)
For Service Fabric you will need to find out how to install certificate in Root Store as well as personal store (if thats possible at all). Here's Links that might be useful
http://ronaldwildenberg.com/running-an-azure-service-fabric-cluster-locally-on-ssl/
https://learn.microsoft.com/en-us/azure/service-fabric/service-fabric-cluster-security-update-certs-azure
Hope this helps.

Certificates, install in local machine before calling a service

I am trying to wrap my head around certificates and any help is appreciated. So far this is what I understand, please correct me if I am wrong.
When using the browser when I navigate to the https site the browser downloads the certificate(without the private key) and then continues to send the data over https?
I have come across some sites (especially when developing) that require you to install the certificate on the local machine before making a service call. What is the purpose here and how does it work?
I have also seen some scenarios where you need to install the certificate on the client machine for authentication purposes for example if you are using an email client, how does this work?
When using the browser when I navigate to the https site the browser downloads the certificate(without the private key) and then continues to send the data over https?
No, the browser and the server stablish a SSL/TLS secure channel with a symmetric encryption key. During the handshake process the server presents the https certificate and digitally signs some data with the private key as a proof of authenticity.
I have come across some sites (especially when developing) that require you to install the certificate on the local machine before making a service call. What is the purpose here and how does it work?
The client must trust the server certificate. Usually it has a list with the Certification Authorities for which certificates are accepted. For other certificates is needed to add them to the trust list. If not, the communication will be rejected
I have also seen some scenarios where you need to install the certificate on the client machine for authentication purposes for example if you are using an email client, how does this work?
Probably the same case as the previous one. Also the public part of the certificate of a user can be used to encrypt a message for him

2 Way SSL - Client Certificate Not Sent To Server

I'm have an application deployed to salesforce on the force.com platform,
which I'm trying to configure a 2 way SSL for.
I.e.
I want that for each request sent to from SF to my server, a client certificate will be sent.
I did the necessary configurations on SF for the certificate to be sent, but I'm still getting 403.7 from the server, which means: forbidden, client certificate required.
I installed wireshark on the server, captured traffic to see the 2 way ssl handshake, and I'm trying to find in the server hello message where it tells the client the trusted CAs from which a client certificate should correspond, but I'm having difficulties finding it.
I suspect that's why the client does not send the certificate.
Can anyone point me to where in the server hello I should look? Or perhaps in another packet capture?
Thanks in advance.
Client Key Exchange record:
Here, the server sends its Certificate Request message and the client sends its Certificate message in response, but that message contains 0 certificates.
Typically, this happens when the client was unable to select a client certificate to use. Either it's not configured properly to make use of any certificate, or it can't find one that is issued by one of the acceptable CAs.
Look at the Certificate Request packet and check its certificate_authorities list. This is a list of the CA Distinguished Names (DNs) that the server is willing to accept.
One way or another, the client will need to find a client certificate with which it can build a chain towards of those DNs. In the simplest case, a client certificate issued by such a DN is available. Otherwise, the client could have to build a chain from a client cert to such a DN, it would need to have the necessary intermediate CA certificates to do so. (How this is done depends on the client's configuration mechanisms.)
If intermediate CA certificates are necessary and not available on the client side, you may need to configure your server to accept them and advertise them in the Certificate Request too.
Added a screenshot of the handshake captures. can you please point me to where I should be looking? –
See packet #31. It contains the Certificate Request. Also packet #33 contains the certificate from the client, so the reason is not the client does not send the certificate, but instead that the server either does not like the certificate because the validation failed or because the certificate is not sufficient as authorization for the requested resource. You might get more information from the servers log.
Not sure if this will help anyone else, but for our case of this issue everything was working when running locally in Visual Studio and in IIS, but when deployed to a real server, we were hitting a certificate issue during 2-way SSL as described above and verified in Wireshark.
Anyway, on that server we have also have a .NET 4.7.2 Console application which was calling the same API and everything was working fine.
But, our .NET 4.7.2 web API calls were failing. It appears that when the same code was running inside IIS the cert was not available during the SSL negotiation. (although it loaded fine)
Our solution at this point was to modify the following call to include the 3rd parameter.
certificate = new X509Certificate2(certificatepath, Password, X509KeyStorageFlags.MachineKeySet);
By default X509Certificate2 uses the UserKeySet option, so perhaps the application pool user or another thread in IIS (?) was having trouble accessing the cert for the negotiation.
Here are a couple of the related pages that I found useful during my research:
https://paulstovell.com/x509certificate2/
https://github.com/dotnet/runtime/issues/23437

WCF Trasnport security with certificate client credentials using NetTcpBinding throws error on distributed system

I want to enable transport security for my Self-Hosted WCF service that uses NetTcpBinding with Certificate as client credential type. The client for this service is a WebAPI. I created certificates using makecert and everything works fine in a single PC. But when I distribute the API and the service to different PCs, I get Certificate errors like "Cannot find Server certificate in Trusted People Store" on the client side even though the certificate is present in the store.
Can someone help me where I have gone wrong?
Store your own certificate in a resources file and read that in , then set the client credential to the certificate you just read.

WCF client only works after accessing URL with IE

We have a wcf client, which calls an external webservice. The service is accessed over SSL. The certificate is not a self signed cert. It is issued by Verisign.
The client is hosted in IIS 6 and the application pool's identity is a domain service user.
Every time we want our client to access the remote service we get the following well known exception: "Could not establish trust relationship for the SSL/TLS secure channel with authority-.."
It turned out, that once you access the URL with IE on the same server, our WCF client is working as expected and the certificate is accepted!
My conclusion is, that the URL accessed with IE modified the server in a way, that our WCF client is able to do the validation afterwards. What is our WCF client missing?
(I'm aware that one can circumvent certificate validation by returning true in the ServerCertificateValidationCallback, but this is not an option for production.)
Considering the situation as described, I suspect that your IIS hosted client is not able to load the Verisign root certificate. And it is always a bit unclear to me under which account such IIS based client is trying to access the certificate store. It might be your domain service account user, it might be the ASP.NET user, it might be some other system defined account. This often causing the error.
When you browse the service with IE, there is no doubt about the user (your own credentials) being able to load the Verisign root certificate and resolve the trust relationship correctly.
Please:
Make sure the Verisign root certificate in in the Trusted Root Authorities store under the Local Computer Account
Have your app.config of your client refer to the correct root certificate to be loaded from the correct store.
You might want to run ProcessMonitor to find out which user is trying to load the certificate from the store.