public HashResult GetHashDocument(ReplayDocument repDoc)
        {
            HashResult result = new HashResult();
            SPSecurity.RunWithElevatedPrivileges(delegate()
            {
                try
                {
                    using (SPSite site = new SPSite(new Guid(repDoc.siteID)))
                    {
                        using (SPWeb web = site.OpenWeb())
                        {
                            SPList list = web.Lists[new Guid(repDoc.listID)];
                            SPFile file = list.GetItemById(Int32.Parse(repDoc.itemID)).File;
                            HashAlgorithm myhash = HashAlgorithm.Create("GOST3411");
                            myhash.ComputeHash(file.OpenBinaryStream());
                            byte[] hashValue = myhash.Hash;
                            result.result = "0";
                            //result.hash = hashValue; //Это пока запасной вариант, потом надо будет удалить
                            result.data = Convert.ToBase64String(hashValue); //Переводим байты в Base64 string. эту последовательность и будем подписывать
                            //for (int i = 0; i < hashValue.Length; i++)
                            //    Console.Write("{0:X2}", hashValue[i]);
                        }
                    }
                }
                catch (Exception ex) {
                    result.result = "Error";
                    result.data = ex.Message + " |&| " + ex.StackTrace;
                }
            });
            return result;
        }

function StartSign() {
            var ReplayDocument = {
                SiteID: globalVari.SiteID,
                ListID: globalVari.ListID,
                ItemID: globalVari.ItemID
            };
            var myJson = JSON.stringify(ReplayDocument);
            var completeUrl = _spPageContextInfo.webAbsoluteUrl + "/_vti_bin/ItemsService/Copy.svc/GetHashDocument";
            $.ajax({
                url: completeUrl,
                contentType: "application/json",
                type: "POST",
                dataType: "Json",
                data: myJson,
                cache: false,
                error: function (err) {
                    alert(err.toString());
                },
                success: function (result) {
                    if (result.Result == "Error") {
                        alert(result.Data);
                    }
                    else {
                        //var el = document.getElementById(<%= tbHash.ClientID %>);
                        $('#<%= tbHashTxt.ClientID %>').val(result.Data);
                        var dd = document.getElementById("<%=ddlSelectSignature.ClientID%>");
                        var signedData = SignCreate($("#<%=ddlSelectSignature.ClientID%> option:selected").val(), result.Data); //Получаем подписанный хэш. result.Data это строка Base64

                        $('#<%= tbHash.ClientID %>').val(signedData); //Выводим подписанный хэш на форму

                        //$('#<%= tbHash.ClientID %>').val(result.Hash);
                    }
                }
            });
        };

 function SignCreate(certSubjectName, dataToSign) {
            var oStore = cadesplugin.CreateObject("CAPICOM.Store");
            oStore.Open(CAPICOM_CURRENT_USER_STORE, CAPICOM_MY_STORE,
            CAPICOM_STORE_OPEN_MAXIMUM_ALLOWED);

            //var oCertificates = oStore.Certificates.Find(
            //CAPICOM_CERTIFICATE_FIND_SUBJECT_NAME, certSubjectName);
            var oCerts = new Enumerator(oStore.Certificates);
            var cert = null;
            for (; !oCerts.atEnd() ; oCerts.moveNext()) {
                
                if (oCerts.item().SerialNumber == certSubjectName)
                    cert = oCerts.item();
            }
            if (cert == null) {
                alert("Certificate not found: " + certSubjectName);
                return;
            }
            //var oCertificate = oCertificates.Item(1);
            var oSigner = cadesplugin.CreateObject("CAdESCOM.CPSigner");
            oSigner.Certificate = cert;

            var oSignedData = cadesplugin.CreateObject("CAdESCOM.CadesSignedData");
            // Значение свойства ContentEncoding должно быть задано
            // до заполнения свойства Content
            oSignedData.ContentEncoding = CADESCOM_BASE64_TO_BINARY;
            oSignedData.Content = dataToSign;

            var sSignedMessage = "";
            try {
                sSignedMessage = oSignedData.SignCades(oSigner, CADESCOM_CADES_BES, true);
            } catch (err) {
                alert("Failed to create signature. Error: " + GetErrorMessage(err));
                return;
            }

            oStore.Close();

            return sSignedMessage;
        }

function Verify(sSignedMessage, dataToVerify) {
            var oSignedData = cadesplugin.CreateObject("CAdESCOM.CadesSignedData");
            try {
                // Значение свойства ContentEncoding должно быть задано
                // до заполнения свойства Content
                oSignedData.ContentEncoding = CADESCOM_BASE64_TO_BINARY;
                oSignedData.Content = dataToVerify;
                oSignedData.VerifyCades(sSignedMessage, CADESCOM_CADES_BES, true);
            } catch (err) {
                alert("Failed to verify signature. Error: " + GetErrorMessage(err));
                return false;
            }

            return true;
        }