[cifs-protocol] Re: Create Access Mask

tridge at samba.org tridge at samba.org
Sat Jun 7 03:20:57 GMT 2008

Hi Sebastian,

 > I was wondering if you were able to review the information that I
 > provided to you about the matter.

sorry for the slow reply, I've been a bit busy at the plugfest this

 > I've been reviewing the info on the document and I would need a little clarification from you.
 >  The mask that you are using 0D F0 FE 00, includes one bit that's described on the document (ACCESS_SYSTEM_SECURITY 0x01000000).
 >  It's not clear to us that you need this mask. Can you clarify what you're doing that you need it or I'd suggest dropping the bit from the mask as I state next...
 > If not, I would suggest to run your test with the following mask:  0C F0 FE 00

The test sends a separate SMB2 CREATE request for each bit, so it
sends 32 separate CREATE calls. Have a look at this capture:


Start at frame 33. There you see it trying a create with a access_mask
of 1. Then at frame 37 it tries it with an access_mask of 2, and so on
up to frame 129 where 0x80000000 is tried.

The test put together all the single bits that give ACCESS_DENIED or
PRIVILEGE_NOT_HELD, and gets this mask 0x0df0fe00.

Many of these bits are not explained in of MS-SMB2, but if
they return ACCESS_DENIED or PRIVILEGE_NOT_HELD then that indicates
they are not ignored, and must have some meaning. 

So, I think you need to document what the meaning of the bits in
0x0df0fe00 that are not in the table in mean. Some of them
are documented (as you noticed, 0x01000000 is documented), but many of
them aren't. They all should be.

Cheers, Tridge

More information about the cifs-protocol mailing list