Bug 60773 - SSLStream not calling RemoteCertificateValidationCallback on High Sierra
Summary: SSLStream not calling RemoteCertificateValidationCallback on High Sierra
Status: NEW
Alias: None
Product: Class Libraries
Classification: Mono
Component: System.Security ()
Version: unspecified
Hardware: Macintosh Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2017-11-20 15:49 UTC by Daniel
Modified: 2017-11-20 15:49 UTC (History)
1 user (show)

Is this bug a regression?: ---
Last known good build:

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Description Daniel 2017-11-20 15:49:00 UTC
This was not an issue on MacOS Sierra and didn't become an issue until High Sierra.

# Steps to reproduce
Using the library https://github.com/dsbenghe/Novell.Directory.Ldap.NETStandard/commits/master with a custom callback for SSL validation the validation never gets called.  
Specifically calling the following does not call the RemoteCertificateValidationCallback 
this.host = host;
this.port = port;
sock = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.IP);
var ipAddresses = Dns.GetHostAddressesAsync(host).Result;
var hostadd = ipAddresses.First(ip => ip.AddressFamily == AddressFamily.InterNetwork);
var ephost = new IPEndPoint(hostadd, port);
var nstream = new NetworkStream(sock, true);
    var sslstream = new SslStream(
    in_Renamed = sslstream;
    out_Renamed = sslstream;
catch (Exception x)
# Expected behavior
The RemoteCertificateValidationCallback should be executed but it never gets called
# Actual behavior
This method never gets called
# Test environment (full version information)
This is on MacOS High Sierra.  This code executed as expected prior to High Sierra and it works correctly in .Net Core 1.1 and 2.0 on High Sierra.  
# StackTrace
"  at Mono.AppleTls.AppleTlsContext.CheckStatusAndThrow (Mono.AppleTls.SslStatus status, Mono.AppleTls.SslStatus[] acceptable) [0x00071] in /Library/Frameworks/Xamarin.Mac.framework/Versions/ \n  at Mono.AppleTls.AppleTlsContext.ProcessHandshake () [0x00026] in