My colleague has been working on a web part in an FBA environment. Among other things, the web part pulls some data from SQL server. The grand plan for this project dictates that a DBA configures data level security in SQL (as opposed to embedding a user ID in a SQL query or some other approach).

The problem is that SQL server doesn’t know anything about our FBA environment so it can’t trust us. We solved this problem by, for lack of a better word, manually impersonating an AD user so that we could connect to SQL such that SQL data level security works.

Even though FBA is an ASP.NET feature, we SharePoint Nation people have taught the various search engines that if you’re querying for FBA, you must mean you want know how to configure FBA in SharePoint. I failed to find find any information on how to enable an FBA oriented ASP.NET application to communicate with SQL in the way we needed.

In the course of researching this, we re-read this article: ASP.NET Impersonation

More research led us to this codproject article: http://www.codeproject.com/KB/cs/cpimpersonation1.aspx

That helped us write our code, which I’ve included below. It’s not the most elegant stuff, but it worked. I hope you find it helpful.

در اینجا کدی که برای ما کار می کرد:

محفوظ void btnSearchCarrier_Click(object sender, EventArgs e)
 {
 امتحان
 {
 ImpersonateUser iU = جدید ImpersonateUser();
 // TODO: Replace credentials
 iU.Impersonate("DomainName", "UserName", "Password");

//
 CODE
//

 iU.Undo();
 }
 گرفتن (سابق استثنا)
 {

 }
 }

// Using Impersonation class as mentioned below.

عمومی کلاس ImpersonateUser
 {
 [DllImport("advapi32.dll", SetLastError = درست)]
 عمومی ایستا extern bool LogonUser(
 String lpszUsername,
 String lpszDomain,
 String lpszPassword,
 int dwLogonType,
 int dwLogonProvider,
 ref IntPtr phToken);

 [DllImport("kernel32.dll", CharSet = CharSet.Auto)]
 خصوصی extern ایستا bool CloseHandle(IntPtr handle);

 خصوصی ایستا IntPtr tokenHandle = جدید IntPtr(0);
 خصوصی ایستا WindowsImpersonationContext impersonatedUser;

 // If you incorporate this code into a DLL, be sure to demand that it
 // runs with FullTrust.
 [PermissionSetAttribute(SecurityAction.Demand, Name = "FullTrust")]
 عمومی void Impersonate(string domainName, string userName, string password)
 {
 امتحان
 {

 // Use the unmanaged LogonUser function to get the user token for
 // the specified user, domain, and password.
 const int LOGON32_PROVIDER_DEFAULT = 0;

 // Passing this parameter causes LogonUser to create a primary token.
 const int LOGON32_LOGON_INTERACTIVE = 2;
 tokenHandle = IntPtr.Zero;

 // Step -1 Call LogonUser to obtain a handle to an access token.
 bool returnValue = LogonUser(
 userName,
 domainName,
 password,
 LOGON32_LOGON_INTERACTIVE,
 LOGON32_PROVIDER_DEFAULT,
 ref tokenHandle); // tokenHandle - new security token

 اگر (false == returnValue)
 {
 int ret = Marshal.GetLastWin32Error();
 مثلا عدم("LogonUser call failed with error code : " +
 ret);
 پرتاب new System.ComponentModel.Win32Exception(ret);
 }

 // Step - 2
 WindowsIdentity newId = جدید WindowsIdentity(tokenHandle);
 // Step -3
 impersonatedUser = newId.Impersonate();

 }
 گرفتن (سابق استثنا)
 {
 مثلا عدم("Exception occurred. " + ex.Message);
 }
 }


 /// <خلاصه>
 /// Stops impersonation
 /// </خلاصه>
 عمومی void Undo()
 {
 impersonatedUser.Undo();
 // Free the tokens.
 اگر (tokenHandle != IntPtr.Zero)
 CloseHandle(tokenHandle);
 }
 }

</پایان>

مشترک شدن در وبلاگ من.

چند هفته قبل, I was working with my developer colleague on a project involving SQL Server Reporting Services plug-in for MOSS. He was developing a web part that provides a fancy front-end to the report proper (از ویژگی های اصلی مراجعه هوشمندانه بر روی یک پارامتر با ارزش چند هزار جستجو در پشت آن).

This was working great in the development environment but in the user acceptance testing (UAT) محیط, it wouldn’t work. Firing up the debugger, we would see exception details like this:

The permissions granted to user ‘UAT_domain\mosssvc’ are insufficient for performing this operation.(rsAccessDenied).

If you do a live search on the above error, you find it’s quite common. Scarily common. The worst kind of common because it has many different potential root causes and everyone’s suggested solution "feels" راست. We probably tried them all.

In our case, the problem was that we had done a backup/restore of DEV to UAT. Somewhere in the data, something was still referring to "DEV_domain" (instead of the updated "UAT_Domain"). We created a new site, added the web part and that solved our problem.

Hopefully this will save someone an hour or two down the line.

</پایان>

مشترک شدن در وبلاگ من.