Question

I need to use SQLCLR to make a stored procedure that uses stuff in .NET 3.5. If I don’t use PERMISSION_SET = UNSAFE I can’t do it, it will just die and give me this error:

Deploy error SQL01268: .Net SqlClient
Data Provider: Msg 6503, Level 16, State 12, Line 1
Assembly ‘system.core, version=3.5.0.0, culture=neutral, publickeytoken=b77a5c561934e089.’ was not found in the SQL catalog.
An error occurred while the batch was being executed.

So I found this article:

http://weblogs.asp.net/paulomorgado/archive/2009/06/13/playing-with-sql-server-clr-integration-part-iv-deploying-to-sql-server-2005.aspx

And the last line says this:

“Now the DBAs won’t definitely let me use this, but it was fun to build it.”

I am not sure if he was referring to the permissions being set to “unsafe”.

So, can some huge gaping hole happen if you do this?

Answer 1

There are three different permission_set options which restrict what the assembly can do

SAFE – Restricts the assembly to managed code

EXTERNAL_ACCESS – allows access to files, network resources, etc..

UNSAFE – Unrestricted access – including the execution of non-managed code

MSDN docs give the following guidance

Specifying UNSAFE enables the code in the assembly complete freedom to perform operations in the SQL Server process space that can potentially compromise the robustness of SQL Server. UNSAFE assemblies can also potentially subvert the security system of either SQL Server or the common language runtime. UNSAFE permissions should be granted only to highly trusted assemblies.

If your assembly only uses features of .NET 3.5, i don’t see why it would need UNSAFE access.

It’s possible you are using one of the types or members disallowed from the System.Core library. Microsoft has a list of these. Disallowed Types and Members in System.Core.dll

There is some more info here. Host Protection Attributes and CLR Integration Programming