Server API for authorization

Question

Hello,
I'm looking for something similar to FOR LOGON trigger in SQL Server, but FOR/AFTER AUTHORIZATION. I prefer solution in T_SQL. If there is any SQL Server API, to hook on event like OnAuthorization it is also OK (C++, C#, etc).
Any idea?
Thanks in advance,
DG

Answer 1

I need to do some work just after authorization is finished - I guess SQL Server executes query in the following workflow:
Authorize --> If user not authorized than return Exception 
               --> Else Parse query --> execute query --> return result
Not really. Rather then interaction between client and server is:
Client (knocks on the door): May I come in?
Server: Show me you credentials.
Client: OK, here they are.
Server: (a) Ah welcome, please come in.
        (b) No, you don't belong here.
        (c) Your credentials were good, but the logon trigger threw you out.
Some time passes, could be microseconds, could be days.
Client: I have a query, please run it for me.
Server: (a) OK, here is the result.
        (b) Nice try, but you need to study the SQL syntax a little closer.
        (d) No, you are not permitted to perform that action or read           that data.
        (d) Oops, I ran into a serious problem, goodbye!
The above is repeated zero to N times and eventually:
Client: Oh, gotta rush! See you later!
Server: It was nice talking to you.
That is, once the user has logged in, no further authorisation takes place except for permission checks. But there are no hooks for permission checks. Furthermore, permission checks can be performed during execution. For instance if a stored procedure calls
a second procedure that has a different owner from the first procedure, the permission check does not occur until the EXEC statement is reached.
If you explain what your really want to achieve (rather the solution you think you have), maybe we can come up with something.
Erland Sommarskog, SQL Server MVP, [email protected]