HTTPS Post failure


I´m trying to send a POST request to an API on my Xamarin Forms application and I´m getting an error that indicates that there is no trust relationship when sending the request. I cannot find out why is this and how to solve it. This is the exception:


System.Net.Http.HttpRequestException: An error occurred while sending the request ---> System.Net.WebException: Error: TrustFailure (The authentication or decryption has failed.) ---> System.IO.IOException: The authentication or decryption has failed. ---> System.IO.IOException: The authentication or decryption has failed. ---> Mono.Security.Protocol.Tls.TlsException: Invalid certificate received from server. Error code: 0xffffffff800b010f at Mono.Security.Protocol.Tls.RecordProtocol.EndReceiveRecord (System.IAsyncResult asyncResult) [0x00031] in /Users/builder/jenkins/workspace/xamarin-android/xamarin-android/external/mono/mcs/class/Mono.Security/Mono.Security.Protocol.Tls/RecordProtocol.cs:430 at Mono.Security.Protocol.Tls.SslClientStream.SafeEndReceiveRecord (System.IAsyncResult ar, System.Boolean ignoreEmpty) [0x00000] in /Users/builder/jenkins/workspace/xamarin-android/xamarin-android/external/mono/mcs/class/Mono.Security/Mono.Security.Protocol.Tls/SslClientStream.cs:256 at Mono.Security.Protocol.Tls.SslClientStream.NegotiateAsyncWorker (System.IAsyncResult result) [0x00071] in /Users/builder/jenkins/workspace/xamarin-android/xamarin-android/external/mono/mcs/class/Mono.Security/Mono.Security.Protocol.Tls/SslClientStream.cs:418 --- End of inner exception stack trace ---


The code resulting in this exception is the following:

MultipartFormDataContent content = new MultipartFormDataContent(); content.Headers.Add("X-Auth-Token", "eb27c17f-8bd6-4b94-bc4f-742e361b4e6a"); content.Headers.ContentType = MediaTypeHeaderValue.Parse("image/jpeg"); content.Add(new ByteArrayContent(myByteImage)); try { HttpResponseMessage response = await _client.PostAsync("", content); string responseContent = await response.Content.ReadAsStringAsync(); } catch (Exception ex) { throw; }


It seems the problem solved putting the following code on MainActivity.cs

System.Net.ServicePointManager.ServerCertificateValidationCallback += (sender, cert, chain, sslPolicyErrors) => { if (cert != null) System.Diagnostics.Debug.WriteLine(cert); return true; };

As @DanielA.White It seems that the mono implementation of HttpClient does not support self signed certificates.


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