Report Viewer Control Authentication

 By default report viewer control uses credentails of user which is presently viewing reports or accessing web page. However this is someting which is not desired in most of the sites. Rather, we prefer to use a service account for authenticating users and this can be dome by implementing "IReportServerCredentials" interface as shown below.

Example

using System;
using System.Data;
using System.Configuration;
using System.Net;
using System.Security.Principal;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using Microsoft.Reporting.WebForms;

public partial class _Default : System.Web.UI.Page
{
    protected void Page_Init(object sender, EventArgs e)
    {
        ReportViewer1.ServerReport.ReportServerCredentials =
            new MyReportServerCredentials();
    }
}

[Serializable]
public sealed class MyReportServerCredentials :
    IReportServerCredentials
{
    public WindowsIdentity ImpersonationUser
    {
        get
        {
            // Use the default Windows user.  Credentials will be
            // provided by the NetworkCredentials property.
            return null;
        }
    }

    public ICredentials NetworkCredentials
    {
        get
        {
            // Read the user information from the Web.config file. 
            // By reading the information on demand instead of
            // storing it, the credentials will not be stored in
            // session, reducing the vulnerable surface area to the
            // Web.config file, which can be secured with an ACL.

            // User name
            string userName =
                ConfigurationManager.AppSettings
                    ["MyReportViewerUser"];

            if (string.IsNullOrEmpty(userName))
                throw new Exception(
                    "Missing user name from web.config file");

            // Password
            string password =
                ConfigurationManager.AppSettings
                    ["MyReportViewerPassword"];

            if (string.IsNullOrEmpty(password))
                throw new Exception(
                    "Missing password from web.config file");

            // Domain
            string domain =
                ConfigurationManager.AppSettings
                    ["MyReportViewerDomain"];

            if (string.IsNullOrEmpty(domain))
                throw new Exception(
                    "Missing domain from web.config file");

            return new NetworkCredential(userName, password, domain);
        }
    }

    public bool GetFormsCredentials(out Cookie authCookie,
                out string userName, out string password,
                out string authority)
    {
        authCookie = null;
        userName = null;
        password = null;
        authority = null;

        // Not using form credentials
        return false;
    }
}