Untitled

using Grpc.Net.Client;
using System;
using System.Net.Http;
using System.Security.Cryptography.X509Certificates;

public class GrpcClientExample
{
    public static void Main(string[] args)
    {
        // Create an HttpClientHandler with CN and SAN verification
        var handler = new HttpClientHandler();
        handler.ServerCertificateCustomValidationCallback = (message, cert, chain, errors) => 
        {
            // Expected CN and SANs (adjust accordingly)
            string expectedCN = "your-expected-cn";
            string[] expectedSANs = { "your-expected-hostname1", "your-expected-hostname2" };

            // Check CN
            if (!cert.GetName().Contains(expectedCN)) 
            {
                Console.WriteLine($"CN mismatch: Expected '{expectedCN}', found '{cert.GetName()}'");
                return false; 
            }

            // Check SANs
            var hasMatchingSAN = false;
            foreach (var san in cert.GetSubjectAlternativeNames())
            {
                if (san.Item1 == 2 && expectedSANs.Contains(san.Item2)) 
                {
                    hasMatchingSAN = true;
                    break;
                }
            }

            if (!hasMatchingSAN) 
            {
                Console.WriteLine($"No matching SAN found in certificate.");
                return false; 
            }

            // If all checks pass, allow the connection
            return true; 
        };

        // ... (rest of the code remains the same)
    }
}