System.Net.CertificateValidationPal.GetRequestCertificateAuthorities C# (CSharp) Method

        internal static string[] GetRequestCertificateAuthorities(SafeDeleteContext securityContext)
        {
            Interop.SspiCli.SecPkgContext_IssuerListInfoEx issuerList =
                (Interop.SspiCli.SecPkgContext_IssuerListInfoEx)SSPIWrapper.QueryContextAttributes(
                    GlobalSSPI.SSPISecureChannel,
                    securityContext,
                    Interop.SspiCli.ContextAttribute.SECPKG_ATTR_ISSUER_LIST_EX);

            string[] issuers = Array.Empty<string>();

            try
            {
                if (issuerList.cIssuers > 0)
                {
                    unsafe
                    {
                        uint count = issuerList.cIssuers;
                        issuers = new string[issuerList.cIssuers];
                        Interop.SspiCli.CERT_CHAIN_ELEMENT* pIL = (Interop.SspiCli.CERT_CHAIN_ELEMENT*)issuerList.aIssuers.DangerousGetHandle();
                        for (int i = 0; i < count; ++i)
                        {
                            Interop.SspiCli.CERT_CHAIN_ELEMENT* pIL2 = pIL + i;
                            if (pIL2->cbSize <= 0)
                            {
                                NetEventSource.Fail(securityContext, $"Interop.SspiCli._CERT_CHAIN_ELEMENT size is not positive: {pIL2->cbSize}");
                            }
                            if (pIL2->cbSize > 0)
                            {
                                uint size = pIL2->cbSize;
                                byte* ptr = (byte*)(pIL2->pCertContext);
                                byte[] x = new byte[size];
                                for (int j = 0; j < size; j++)
                                {
                                    x[j] = *(ptr + j);
                                }

                                X500DistinguishedName x500DistinguishedName = new X500DistinguishedName(x);
                                issuers[i] = x500DistinguishedName.Name;
                                if (NetEventSource.IsEnabled) NetEventSource.Info(securityContext, "IssuerListEx[{issuers[i]}]");
                            }
                        }
                    }
                }
            }
            finally
            {
                if (issuerList.aIssuers != null)
                {
                    issuerList.aIssuers.Dispose();
                }
            }

            return issuers;
        }