SharePoint -access to path is denied

Question

I am working in SharePoint 2010. My requirement is to create folder inside SharePoint layouts and create a file inside that folder. Also I need to access the file for a current logged in user.

Layouts-> Files-->file1.txt.

Please check out the code below.

String tempFilePath = SPUtility.GetGenericSetupPath(String.Empty) + "TEMPLATE\\LAYOUTS\\Files";         

DirectorySecurity securityRules = new DirectorySecurity();
securityRules.AddAccessRule(new FileSystemAccessRule(strUserName, FileSystemRights.FullControl, AccessControlType.Allow));
bool IsExist = System.IO.Directory.Exists(v);

if (!IsExist )
System.IO.Directory.CreateDirectory(tempFilePath ,securityRules); 

In the code above if the strUserName is Administrator then the directory(Files) will be created successfully. But for other than Administrator account CreateDirectory will fail( access to the path denied). Can anyone tell me how can I create the folder in sharpoint layouts for any user with full permission?

Answer 1

you should impersonate user for operation

SPSecurity.RunWithElevatedPrivileges(delegate
{
    using(SPSite site = SPContext.Current.Site.ID)
    {
        using(SPWeb web =  SPContext.Current.Web.ID)
        {
           //code
        }
    }
});

Answer 2

Just to clarifiy, runwithelevatedprivlages is not impersonation:

a good example is an anonymous user who you want to edit (add to) a sharepoint list that they dont have access to programmaticaly.

runwithelevatedprivlages will not work as anonymous users wouldnt have anything to elevate, this is where you need to impersonate an account that does have access. runwithelevatedprivlages works well with logged in users who dont have the right permissions.

as an example I will show you impersonation first:

to impersonate you need to get the system token first and make sharepoint think that your that person, anything within the spsite that your going to impersonate will be under that user and not the current user your using, the method below is getting the system account token with elevated privlages (for anonymous users):

    /// <summary>
    /// get the system token from the list of users to elevate spsite
    /// </summary>
    /// <param name="spSite"></param>
    /// <returns></returns>
    protected static SPUserToken GetSystemToken(SPSite spSite) 
    {     
        SPUserToken res = null;     
        bool oldCatchAccessDeniedException = spSite.CatchAccessDeniedException;
        try
        {
            spSite.CatchAccessDeniedException = false;
            res = spSite.SystemAccount.UserToken;
        }
        catch (UnauthorizedAccessException)
        {
            SPSecurity.RunWithElevatedPrivileges(delegate()
            {
                using (SPSite elevatedSPSite = new SPSite(spSite.ID))
                    res = elevatedSPSite.SystemAccount.UserToken;
                // (***)         
            });
        }
        finally    
        {         
            spSite.CatchAccessDeniedException = oldCatchAccessDeniedException;     
        }     
        return res; 
    }

to use this method you would need to do the following:

            SPUserToken sysToken = null;
            using (SPSite spSite = new SPSite(SPContext.Current.Site.ID))
            {
                //get the system token from the method GetSystemToken and passing the spSite that you want to run under
                sysToken = GetSystemToken(spSite);

                using (SPSite impersonatedSite = new SPSite(siteUrl, sysToken))
                {
                    //we are impersonating the [@"SHAREPOINT\SYSTEM"] account
                    using (SPWeb web = impersonatedSite.OpenWeb())
                    {
                         //do your code here as the impersonated account like updating a list
                    }
                }
            }

this will work where RunWithElevatedPrivileges does not work :) as you can see there is suttle differences between the two, impersonation is not using the application pool account but rather any account that you want to impersonate. RunWithElevatedPrivileges only uses the application pool account and has some limitation to what access it has (your only elevating the current account!! not impersonating the app pool account)

msdn RunWithElevatedPrivileges explained

http://msdn.microsoft.com/en-us/library/microsoft.sharepoint.spsecurity.runwithelevatedprivileges.aspx

msdn Impersonation explained

http://msdn.microsoft.com/en-us/library/aa543158(v=office.14).aspx

http://msdn.microsoft.com/en-gb/library/windows/desktop/ms691341(v=vs.85).aspx

for the op, I would suggest as others and use RunWithElevatedPrivileges as it should be more than enough :)

hope this helps :)

Answer 3

You should wrap your code in SPSecurity.RunWithElevatedPrivileges:

SPSecurity.RunWithElevatedPrivileges(delegate
{
    /// your code here
});

The code inside RunWithElevatedPrivileges executes under current application pool account instead of logged in user account, so make sure that this pool account has access to local file system.

Answer 4

Why do you need to store files on file system? Will blob storage be better?