Prevent Access to Custom Web Application Pages by Non-Admin Users in SharePoint

Question

I have a custom web application that integrates with a SharePoint (MOSS 2007) solution. I would like to add role-based access to pages in this custom web application, with only users in a specified SharePoint group or with a specific role being able to access them. Other users being sent to the default OOTB web page, giving the message "You Are Not Authorized to View This Page".

Can anyone point me towards tutorials on how to implement this, and how to control access on each custom page?

Please note, these pages are part of the custom web application, and are NOT created via the SharePoint API or interface.

Thanks, MagicAndi.

Update

Just to make you aware, I am hoping for a solution where we can make use of the SharePoint functionality to extend security trimming or item permissions to limit access to the custom web application pages. I already have code to check a user's SPGroup on page load, and to redirect if required. Thanks.

Answer 1

I have a similar setting on my current project, I changed it a bit to make more sense to your question, we use a base class for custom webpages, something like:

public abstract class WebPageBase : Page
{
    public SPBasePermissions PagePermissionFlag;
    public override void OnInit(EventArgs e)
    {
        SPWeb web = SPContext.Current.Web;
        if(!web.DoesUserHavePermissions(PagePermissionFlag))
        {
            // build the access denied page
            SPUtility.Redirect(SPUtility.AccessDeniedPage + "?Source=" + SPHttpUtility.UrlKeyValueEncode(web.Site.MakeFullUrl(Request.RawUrl)),
                               SPRedirectFlags.RelativeToLayoutsPage,
                               HttpContext.Current);
        }

    }
}

Then on the page itself, the permission is defined:

public class ContentPage : WebPageBase
{
    protected void Page_PreInit(Object sender, EventArgs e)
    {
        PagePermissionFlag = SPBasePermissions.ViewFormPages;
    }
}

Note: you can also set that on the:

<%@Page PagePermissionFlagString="SPBasePermissions.ViewFormPages"%> *

Just for reference, this extra bit is unrelated to the implementation above, its how we use it internally:

public static class CurrentUser
{
    public static bool IsAdmin
    {
        get
        {
            return SPContext.Current.Web.DoesUserHavePermissions(SPBasePermissions.ManageWeb);
        }
    }

    public static bool IsReader
    {
        get
        {
            return SPContext.Current.Web.DoesUserHavePermissions(SPBasePermissions.ViewFormPages);
        }
    }
}

Answer 2

You will have to implement the ItemLevel security to the pages. Go to the Pages Library and select the Pages Property and Say Item Permissions,break the Permission in it and add only the users who you want to give the access to. In case if you want to add this to multiple files, you can group them in to a seperate folders and apply the permission those folders alone.

And When some try to see the page that he is not supposed to see, SharePoint automatically sends hime the Access Denied Page.

If you apply item level permission on the page, SharePOint automatically applies the Security Trimmings so that only the Pages to which he has access can been seen not others.

Answer 3

Take a look at Users and Groups Web Service exposed by Sharepoint. Your custom web app can call its methods to obtain information about current user profile.

For example the UserGroup.GetUserInfo() method returns IsSiteAdmin flag which can answer your question.

http://msdn.microsoft.com/en-us/library/ms774637.aspx