.NET Core Refit HTTPS errors

Question

I have the below code, which uses Refit to make an HTTPS call. It works from a console application targeting the .NET framework 4.6.1.

When I run the exact same code from a console application targeting .NET Core 2.1 I get an error:

The SSL connection could not be established... An unknown error occurred while processing the certificate

I'm using Refit version 4.5.6

System.Net.ServicePointManager.SecurityProtocol =
    SecurityProtocolType.Tls | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls12;

var baseAddress = new Uri(BaseHttpsAddress);
var httpClientHandler = new HttpClientHandler
{
    ClientCertificateOptions = ClientCertificateOption.Automatic
};

var httpClient = new HttpClient(httpClientHandler) { BaseAddress = baseAddress, Timeout = _requestTimeout };

var service = RestService.For<IMyService>(httpClient);

var result = await service.GetUsers();

In fact when targeting .NET Core 2.1 all my HTTPS calls fail, but my HTTP calls work fine.

Is there some configuration or something to get HTTPS calls working in a .NET Core 2.1 application using Refit?

score 1 · Answer 1 · answered Aug 29 '18 at 07:26

I am trying to accept all server certificates as valid by the below code.. However in real-time, you add the logic to validate the server certificate.

System.Net.ServicePointManager.SecurityProtocol =
            SecurityProtocolType.Tls | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls12;

....
 ServicePointManager.ServerCertificateValidationCallback += (sender, cert, chain, sslPolicyErrors) => true; 
...
// your https call goes here
....

score 0 · Answer 2 · edited Apr 02 '21 at 22:29

0

You need to tell the ServicePointManager to accept the connections using TLS (appropriate version) protocol. Try Default SecurityProtocol in .NET 4.5. This one is for .NET 4.5. However the same is applicable for .NET Core.

edited Apr 02 '21 at 22:29

Peter Mortensen

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answered Aug 28 '18 at 11:38

Satheesh K

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Unfortunately it still doesn't work after adding SecurityProtocol = SecurityProtocolType.Tls | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls12; ... i updated the code in my question – Bob Aug 28 '18 at 11:45
1

When i try that it says SSL3 is obsolete and no longer supported – Bob Aug 28 '18 at 13:06

score 0 · Answer 3 · edited Apr 02 '21 at 22:31

0

Regular .NET automatically checks the Windows certificates installed and .NET Core doesn't.

So with .NET Core I needed to manually add the certificate and it worked.

edited Apr 02 '21 at 22:31

Peter Mortensen

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answered Aug 28 '18 at 16:15

Bob

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.NET Core Refit HTTPS errors

3 Answers3