CLR Stored Procedure "Failed to get permission to execute"

Hello All,
This is variant/continuation of a problem I've discussed on the
sqlserver.programming group (Thanks to Erland for a lot of help over there).
I thought it might benefit me to raise the issue here as well.
In a nutshell:
I have a C# stored procedure (called SProc, in cs.dll, but "imported" as
"csfn") that uses PInvoke to access a function in a C++ dll (called
cpp.dll). The function is __declspec(dllexport)'d. If the C++ dll is
UNMANAGED this now seems to work OK. (Thank again to Erland helping me get
this far). Now, if I add some managed code to the C++ dll (leaving the
unmanaged entry point unchanged, but now compiling with /clr) I get a
"Failed to get permisssion to execute" message as below.
I've tried all the obvious (to me anyway) ways of adding the appropriate
permissions. I've used the "Trust Assembly" node of the .Net 2.0
Configuration tool to give "Full Trust" to both cs.dll AND cpp.dll but it
still fails. I've confirmed that I can call the C++ dll from a c# EXE from
the command line, and that works OK.
I'd really appreciate any help.
/john
Error text follows.
Msg 6522, Level 16, State 1, Procedure csfn, Line 0
A .NET Framework error occurred during execution of user defined routine or
aggregate 'csfn':
System.IO.FileLoadException: Could not load file or assembly 'cpp,
Version=11.0.1.0, Culture=neutral, PublicKeyToken=eb5ebc232de94dcf' or one
of its dependencies. Failed to grant permission to execute. (Exception from
HRESULT: 0x80131418) --> System.Security.Policy.PolicyException: Execution
permission cannot be acquired.
System.Security.Policy.PolicyException:
at System.Security.SecurityManager.ResolvePolicy(Evidence evidence,
PermissionSet reqdPset, PermissionSet optPset, PermissionSet denyPset,
PermissionSet& denied, Boolean checkExecutionPermission)
at System.Security.SecurityManager.ResolvePolicy(Evidence evidence,
PermissionSet reqdPset, PermissionSet optPset, PermissionSet denyPset,
PermissionSet& denied, Int32& securitySpecialFlags, Boolean
checkExecutionPermission)
System.IO.FileLoadException:
at DotNetFun.SqlServer.SProc.CPPTest()
at DotNetFun.SqlServer.SProc.CPPTest()
at DotNetFun.SqlServer.SProc.PrintMessage(String Message)
.Hello Eric,
The consensus is (I think), that you can use pInvoke to call an
unmanaged DLL from a managed stored procedure. However, it looks like
calling a MIXED (ie managed and unmanaged) DLL is not going to work. You can
look at the thread I started on the sqlserver.programming group for more
information.
It seems that mixed and/or managed DLLs need to be added to SQL with
CREATE ASSEMBLY, and this fails on a mixed dll, even if set it as UNSAFE.
I'd like to establish if that is expected to work, but I suspect it is
failing for good reason.
/john
"Eric" wrote in message news:200762618736eric_hackett@.kindermorg
an.com...
> Did you find any satisfaction for this? I have a nearly identical problem.
> Using a third party dll, wrapping it with my own dll, and then writing CLR
> stored proc to use wrapped function. Other functions in the stored proc
> dll work. Only the ones that need external resources are choking.
> Please reply here if you get this working.
> EggHeadCafe.com - .NET Developer Portal of Choice
> http://www.eggheadcafe.com