SSL connection could not be established on android prior 9

Question

Here is my scenario:

• ASP.NET Core API server on azure using https
• MAUI app, the android apk supporting from android 5.0+
• installed on various devices:
• huawei with android 10 on two devices: works perfectly
• pixel 2 with android 11: works perfectly
• pixel 4 with android 13: works perfectly
• nokia with android 11: works perfectly
• some old android 5.1 and other android 10 does not work
• emulator with android 7 or 8: doesn't work

So same build, works on most of the devices, doesn't work on others. Exception I get on android 5.1 is:

The ssl connection could not be established. See inner exception.

And in the inner exception I get:

System.PlatformNotSupportedExcetpion: Setting an SNI hostname is not supported on this API level.

I assume that this may be because android 5 is really old. However, I managed to get another inner exception when running on android 7 and 8 emulators.

The ssl connection could not be established. See inner exception.

However the inner exception is different:

System.Security.Authentication.AuthenticationException: Authentication failed, see inner exception --> Interop.AndroidCrypto+SslExcetion: Exception of type 'Interop+AndroidCrypto+SslException was thrown -- End o inner exception stack trace at System.Net.Security.SslStream.

The code that makes the call is simple:

var httpClient = new HttpClient();
var responseFromServer = await httpClient.PostAsync(url, stringContent)

Any idea how to fix this? Maybe some backward compatibility settings on the server side? Something in android app?

Answer 1

Maybe these could help you:

https://github.com/dotnet/runtime/issues/74292

Answer 2

Definitely use IHttpClientFactory to create HttpClient - the wrong way of initialization.

It caused so much trouble for me.

Nice example here for Net MAUI

https://github.com/yogigrantz/MAUIWithHttpClientFactory/tree/main/MAUIMultiPage

builder.Services.AddHttpClient();