CIFS proxy using VFS

[Jeremy Allison]

On Thu, Jun 16, 2016 at 05:03:22PM +0100, Chris Miller wrote:
> 
> Hi,
> 
> I asked a question back in Jan about getting vfs_cifs proxy working (in the NTVFS codebase). I did get it working, also using kerberos forwarding and was interested to know if it would be feasible/possible to write a similar proxy module in the normal vfs codebase/style without the NTVFS codebase.
> 
> https://lists.samba.org/archive/samba-technical/2016-January/111832.html <https://lists.samba.org/archive/samba-technical/2016-January/111832.html>
> 
> My question, if it is feasible to build an SMB/SMB2 proxy in vfs, is it possible to use the same S42UProxy forwarding mechanism that was used in the original vfs_cifs? is support already available for this in the other codebase?

It's a little better than it was, in that the Create call
is now passed in pretty much unchanged. Having said
that the correct place to catch these is probably
to add a struct that catches the calls at the
smbd_smb2_request_process_XXX() call level.

These are the relevent calls:

source3/smbd/globals.h:NTSTATUS smbd_smb2_request_process_negprot(struct smbd_smb2_request *req);
source3/smbd/globals.h:NTSTATUS smbd_smb2_request_process_sesssetup(struct smbd_smb2_request *req);
source3/smbd/globals.h:NTSTATUS smbd_smb2_request_process_logoff(struct smbd_smb2_request *req);
source3/smbd/globals.h:NTSTATUS smbd_smb2_request_process_tcon(struct smbd_smb2_request *req);
source3/smbd/globals.h:NTSTATUS smbd_smb2_request_process_tdis(struct smbd_smb2_request *req);
source3/smbd/globals.h:NTSTATUS smbd_smb2_request_process_create(struct smbd_smb2_request *req);
source3/smbd/globals.h:NTSTATUS smbd_smb2_request_process_close(struct smbd_smb2_request *req);
source3/smbd/globals.h:NTSTATUS smbd_smb2_request_process_flush(struct smbd_smb2_request *req);
source3/smbd/globals.h:NTSTATUS smbd_smb2_request_process_read(struct smbd_smb2_request *req);
source3/smbd/globals.h:NTSTATUS smbd_smb2_request_process_write(struct smbd_smb2_request *req);
source3/smbd/globals.h:NTSTATUS smbd_smb2_request_process_lock(struct smbd_smb2_request *req);
source3/smbd/globals.h:NTSTATUS smbd_smb2_request_process_ioctl(struct smbd_smb2_request *req);
source3/smbd/globals.h:NTSTATUS smbd_smb2_request_process_keepalive(struct smbd_smb2_request *req);
source3/smbd/globals.h:NTSTATUS smbd_smb2_request_process_query_directory(struct smbd_smb2_request *req);
source3/smbd/globals.h:NTSTATUS smbd_smb2_request_process_notify(struct smbd_smb2_request *req);
source3/smbd/globals.h:NTSTATUS smbd_smb2_request_process_getinfo(struct smbd_smb2_request *req);
source3/smbd/globals.h:NTSTATUS smbd_smb2_request_process_setinfo(struct smbd_smb2_request *req);
source3/smbd/globals.h:NTSTATUS smbd_smb2_request_process_break(struct smbd_smb2_request *req);

called from smbd_smb2_request_dispatch(). If you can
ignore SMB1 requests that would be best.