Which library(.dll) should be used to use the IOS MDM protocol sample .net code

<pre lang="c#">
var privateKey = new PrivateKey(PrivateKey.KeySpecification.AtKeyExchange, 2048, false, true);

            var caCertificateRequest = new CaCertificateRequest(); 

            string csr = caCertificateRequest.GenerateRequest("cn=test", privateKey);

            //Load signing certificate from MDM_pfx.pfx, this is generated using signingCertificatePrivate.pem and SigningCert.pem.pem using openssl
           
            var cert = new X509Certificate2(MY_MDM_PFX, PASSWORD, X509KeyStorageFlags.Exportable);

            //RSA provider to generate SHA1WithRSA

            var crypt = (RSACryptoServiceProvider)cert.PrivateKey;
            var sha1 = new SHA1CryptoServiceProvider();
            byte[] data = Convert.FromBase64String(csr);
            byte[] hash = sha1.ComputeHash(data);
            //Sign the hash 
            byte[] signedHash = crypt.SignHash(hash, CryptoConfig.MapNameToOID("SHA1")); 
            var signedHashBytesBase64 = Convert.ToBase64String(signedHash);