MQTTnet/Source/MQTTnet/Client/Options/MqttClientTlsOptions.cs

using System;
using System.Collections.Generic;
using System.Net.Security;
using System.Security.Authentication;
using System.Security.Cryptography.X509Certificates;

namespace MQTTnet.Client.Options
{
    public class MqttClientTlsOptions
    {
        public bool UseTls { get; set; }

        public bool IgnoreCertificateRevocationErrors { get; set; }

        public bool IgnoreCertificateChainErrors { get; set; }

        public bool AllowUntrustedCertificates { get; set; }

#if WINDOWS_UWP
        public List<byte[]> Certificates { get; set; }
#else
        public List<X509Certificate> Certificates { get; set; }
#endif

#if NETCOREAPP3_1
		public List<SslApplicationProtocol> ApplicationProtocols {get;set;}
#endif

        public SslProtocols SslProtocol { get; set; } = SslProtocols.Tls12;

        [Obsolete("This property will be removed soon. Use CertificateValidationHandler instead.")]
        public Func<X509Certificate, X509Chain, SslPolicyErrors, IMqttClientOptions, bool> CertificateValidationCallback { get; set; }

        public Func<MqttClientCertificateValidationCallbackContext, bool> CertificateValidationHandler { get; set; }
    }
}