Open Questions about RPCNetlogon

Windows servers repond to 46 functions on the RPCNetlogon interface, of which we names and at least paritial decoding information for 30 in Samba4's IDL.

Padding fields

A number of the calls on this pipe have a series of 32-bit fields and strings as 'expansion room' in a way not seen on other similar DCE/RPC interfaces. While we know these exist, we do not know if they have some as-yet unknown meaning.

For example, in the calls DatabaseDeltas (op 0x07) and DatabaseDeltas (op 0x08), we are returned a list of deltas. Many of the delta levels (such as DELTA_USER, switch level 0x5) contain 4 strings and 4 integers as apparent 'padding'.

ServerAuthenticate2/3 flags

The ServerAuthenticate2 (op 0x0f) and ServerAuthencate3 (op 0x1a) functions on this DCE/RPC interface have an in/out negotiate_flags field. We know of only 3 valid flags:

While the pattern is interesting, it is unclear if these are the only valid flags, as others are sent. The other oddity with this feild is that the server uses it to detect 'NT4' clients. Which bit Win2k client set to indicate 'not NT4' is unclear, but an overall pattern of 0x0701ff seems to be 'not NT4'.

SamLogon parameters

The SamLogon call is used to log users onto a client workstation, or for the validation of an attempted network access. It has 3 variations: SamLogon (op 0x02), SamLogonEx (op 0x27) and SamLogonWithFlags (op 0x2d). All permit multiple logon levels, but we do not know how to perform some things:

RPCNetlogon/OpenQuestions (last edited 2008-04-12 17:51:37 by localhost)