!==
!== cifsntdomain.txt for Samba release 2.2.0-alpha3 24 Mar 2001
!==
NT Domain Authentication
------------------------
Authors: - Luke Kenneth Casson Leighton (lkcl@switchboard.net)
-------- - Paul Ashton (paul@argo.demon.co.uk)
- Duncan Stansfield (duncans@sco.com)
Copyright (C) 1997 Luke Kenneth Casson Leighton
Copyright (C) 1997 Paul Ashton
Copyright (C) 1997 Duncan Stansfield
Version: 0.024 (01Nov97)
--------
Distribution: Unlimited and encouraged, for the purposes of implementation
------------- and comments. Feedback welcomed by the authors.
Liability: Absolutely none accepted implicitly or explicitly, direct
---------- or consequentially, for use, abuse, misuse, lack of use,
misunderstandings, mistakes, omissions, mis-information for
anything in or not in, related to or not related to, or
pertaining to this document, or anything else that a lawyer
can think of or not think of.
Warning: Please bear in mind that an incorrect implementation of this
-------- protocol can cause NT workstation to fail irrevocably, for
which the authors accept no liability (see above). Please
contact your vendor if you have any problems.
Sources: - Packet Traces from Netmonitor (Service Pack 1 and above)
-------- - Paul Ashton and Luke Leighton's other "NT Domain" doc.
- CIFS documentation - cifs6.txt
- CIFS documentation - cifsrap2.txt
Original: http://mailhost.cb1.com/~lkcl/cifsntdomain.txt.
--------- (Controlled copy maintained by lkcl@switchboard.net)
Credits: - Paul Ashton: loads of work with Net Monitor;
-------- understanding the NT authentication system;
reference implementation of the NT domain support on which
this document is originally based.
- Duncan Stansfield: low-level analysis of MSRPC Pipes.
- Linus Nordberg: producing c-code from Paul's crypto spec.
- Windows Sourcer development team
Contents:
---------
1) Introduction
2) Structures and notes
2.1) Notes
2.3) Enumerations
2.3) Structures
3) Transact Named Pipe Header/Tail
3.1) MSRPC Pipes
3.2) Header
3.3) Tail
4) NTLSA Transact Named Pipe
4.1) LSA Open Policy
4.2) LSA Query Info Policy
4.3) LSA Enumerate Trusted Domains
4.4) LSA Open Secret
4.5) LSA Close
4.6) LSA Lookup SIDS
4.7) LSA Lookup Names
5) NETLOGON rpc Transact Named Pipe
5.1) LSA Request Challenge
5.2) LSA Authenticate 2
5.3) LSA Server Password Set
5.4) LSA SAM Logon
5.5) LSA SAM Logoff
6) \\MAILSLOT\NET\NTLOGON
6.1) Query for PDC
6.2) SAM Logon
7) SRVSVC Transact Named Pipe
7.1) Net Share Enum
7.2) Net Server Get Info
Appendix:
---------
A1) Cryptographic side of NT Domain Authentication
A1.1) Definitions
A1.2) Protocol
A1.3) Comments
A2) SIDs and RIDs
A2.1) Well-known SIDs
A2.1.1) Universal well-known SIDs
A2.1.2) NT well-known SIDs
A2.2) Well-known RIDS
A2.2.1) Well-known RID users
A2.2.2) Well-known RID groups
A2.2.3) Well-known RID aliases
1) Introduction
---------------
This document contains information to provide an NT workstation with login
services, without the need for an NT server.
It should be possible to select a domain instead of a workgroup (in the NT
workstation's TCP/IP settings) and after the obligatory reboot, type in a
username, password, select a domain and successfully log in. I would
appreciate any feedback on your experiences with this process, and any
comments, corrections and additions to this document.
The packets described here can be easily derived from (and are probably
better understood using) Netmon.exe. You will need to use the version
of Netmon that matches your system, in order to correctly decode the
NETLOGON, lsarpc and srvsvc Transact pipes. This document is derived from
NT Service Pack 1 and its corresponding version of Netmon. It is intended
that an annotated packet trace be produced, which will likely be more
instructive than this document.
Also needed, to fully implement NT Domain Login Services, is the
document describing the cryptographic part of the NT authentication.
This document is available from comp.protocols.smb; from the ntsecurity.net
digest and from the samba digest, amongst other sources.
A copy is available from:
http://ntbugtraq.rc.on.ca/SCRIPTS/WA.EXE?A2=ind9708&L=ntbugtraq&O=A&P=2935
http://mailhost.cb1.com/~lkcl/crypt.html
A c-code implementation, provided by Linus Nordberg <linus@incolumitas.se>
of this protocol is available from:
http://samba.org/cgi-bin/mfs/01/digest/1997/97aug/0391.html
http://mailhost.cb1.com/~lkcl/crypt.txt
Also used to provide debugging information is the Check Build version of
NT workstation, and enabling full debugging in NETLOGON. This is
achieved by setting the following REG_SZ registry key to 0x1ffffff:
HKLM\SYSTEM\CurrentControlSet\Services\Netlogon\Parameters
- Incorrect direct editing of the registry can cause your machine to fail.
Then again, so can incorrect implementation of this protocol.
See "Liability:" above.
Bear in mind that each packet over-the-wire will have its origin in an
API call. Therefore, there are likely to be structures, enumerations
and defines that are usefully documented elsewhere.
This document is by no means complete or authoritative. Missing sections
include, but are not limited to:
- the meaning (and use by NT) of SIDs and RIDs.
- mappings of RIDs to usernames (and vice-versa).
- what a User ID is and what a Group ID is.
- the exact meaning/definition of various magic constants or enumerations.
- the reply error code and use of that error code when a workstation
becomes a member of a domain (to be described later). Failure to
return this error code will make the workstation report that it is
already a member of the domain.
- the cryptographic side of the NetrServerPasswordSet command, which would
allow the workstation to change its password. This password is used to
generate the long-term session key. [It is possible to reject this
command, and keep the default workstation password].
2) Notes and Structures
-----------------------
2.1) Notes
----------
- In the SMB Transact pipes, some "Structures", described here, appear to be
4-byte aligned with the SMB header, at their start. Exactly which
"Structures" need aligning is not precisely known or documented.
- In the UDP NTLOGON Mailslots, some "Structures", described here, appear to be
2-byte aligned with the start of the mailslot, at their start.
- Domain SID is of the format S-revision-version-auth1-auth2...authN.
e.g S-1-5-123-456-789-123-456. the 5 could be a sub-revision.
- any undocumented buffer pointers must be non-zero if the string buffer it
refers to contains characters. exactly what value they should be is unknown.
0x0000 0002 seems to do the trick to indicate that the buffer exists. a
NULL buffer pointer indicates that the string buffer is of zero length.
If the buffer pointer is NULL, then it is suspected that the structure it
refers to is NOT put into (or taken out of) the SMB data stream. This is
empirically derived from, for example, the LSA SAM Logon response packet,
where if the buffer pointer is NULL, the user information is not inserted
into the data stream. Exactly what happens with an array of buffer pointers
is not known, although an educated guess can be made.
- an array of structures (a container) appears to have a count and a pointer.
if the count is zero, the pointer is also zero. no further data is put
into or taken out of the SMB data stream. if the count is non-zero, then
the pointer is also non-zero. immediately following the pointer is the
count again, followed by an array of container sub-structures. the count
appears a third time after the last sub-structure.
2.2) Enumerations
-----------------
- MSRPC Header type. command number in the msrpc packet header
MSRPC_Request: 0x00
MSRPC_Response: 0x02
MSRPC_Bind: 0x0B
MSRPC_BindAck: 0x0C
- MSRPC Packet info. the meaning of these flags is undocumented
FirstFrag: 0x01
LastFrag: 0x02
NotaFrag: 0x04
RecRespond: 0x08
NoMultiplex: 0x10
NotForIdemp: 0x20
NotforBcast: 0x40
NoUuid: 0x80
2.3) Structures
---------------
- sizeof VOID* is 32 bits.
- sizeof char is 8 bits.
- UTIME is 32 bits, indicating time in seconds since 01jan1970. documented
in cifs6.txt (section 3.5 page, page 30).
- NTTIME is 64 bits. documented in cifs6.txt (section 3.5 page, page 30).
- DOM_SID (domain SID structure) :
UINT32 num of sub-authorities in domain SID
UINT8 SID revision number
UINT8 num of sub-authorities in domain SID
UINT8[6] 6 bytes for domain SID - Identifier Authority.
UINT16[n_subauths] domain SID sub-authorities
Note: the domain SID is documented elsewhere.
- STR (string) :
char[] null-terminated string of ascii characters.
- UNIHDR (unicode string header) :
UINT16 length of unicode string
UINT16 max length of unicode string
UINT32 4 - undocumented.
- UNIHDR2 (unicode string header plus buffer pointer) :
UNIHDR unicode string header
VOID* undocumented buffer pointer
- UNISTR (unicode string) :
UINT16[] null-terminated string of unicode characters.
- NAME (length-indicated unicode string) :
UINT32 length of unicode string
UINT16[] null-terminated string of unicode characters.
- UNISTR2 (aligned unicode string) :
UINT8[] padding to get unicode string 4-byte aligned
with the start of the SMB header.
UINT32 max length of unicode string
UINT32 0 - undocumented
UINT32 length of unicode string
UINT16[] string of uncode characters.
- OBJ_ATTR (object attributes) :
UINT32 0x18 - length (in bytes) including the length field.
VOID* 0 - root directory (pointer)
VOID* 0 - object name (pointer)
UINT32 0 - attributes (undocumented)
VOID* 0 - security descriptior (pointer)
UINT32 0 - security quality of service
- POL_HND (LSA policy handle) :
char[20] policy handle
- DOM_SID2 (domain SID structure, SIDS stored in unicode) :
UINT32 5 - SID type
UINT32 0 - undocumented
UNIHDR2 domain SID unicode string header
UNISTR domain SID unicode string
Note: there is a conflict between the unicode string header and the
unicode string itself as to which to use to indicate string
length. this will need to be resolved.
Note: the SID type indicates, for example, an alias; a well-known group etc.
this is documented somewhere.
- DOM_RID (domain RID structure) :
UINT32 5 - well-known SID. 1 - user SID (see ShowACLs)
UINT32 5 - undocumented
UINT32 domain RID
UINT32 0 - domain index out of above reference domains
- LOG_INFO (server, account, client structure) :
Note: logon server name starts with two '\' characters and is upper case.
Note: account name is the logon client name from the LSA Request Challenge,
with a $ on the end of it, in upper case.
VOID* undocumented buffer pointer
UNISTR2 logon server unicode string
UNISTR2 account name unicode string
UINT16 sec_chan - security channel type
UNISTR2 logon client machine unicode string
- CLNT_SRV (server, client names structure) :
Note: logon server name starts with two '\' characters and is upper case.
VOID* undocumented buffer pointer
UNISTR2 logon server unicode string
VOID* undocumented buffer pointer
UNISTR2 logon client machine unicode string
- CREDS (credentials + time stamp)
char[8] credentials
UTIME time stamp
- CLNT_INFO2 (server, client structure, client credentials) :
Note: whenever this structure appears in a request, you must take a copy
of the client-calculated credentials received, because they will be
used in subsequent credential checks. the presumed intention is to
maintain an authenticated request/response trail.
CLNT_SRV client and server names
UINT8[] ???? padding, for 4-byte alignment with SMB header.
VOID* pointer to client credentials.
CREDS client-calculated credentials + client time
- CLNT_INFO (server, account, client structure, client credentials) :
Note: whenever this structure appears in a request, you must take a copy
of the client-calculated credentials received, because they will be
used in subsequent credential checks. the presumed intention is to
maintain an authenticated request/response trail.
LOG_INFO logon account info
CREDS client-calculated credentials + client time
- ID_INFO_1 (id info structure, auth level 1) :
VOID* ptr_id_info_1
UNIHDR domain name unicode header
UINT32 param control
UINT64 logon ID
UNIHDR user name unicode header
UNIHDR workgroup name unicode header
char[16] arc4 LM OWF Password
char[16] arc4 NT OWF Password
UNISTR2 domain name unicode string
UNISTR2 user name unicode string
UNISTR2 workstation name unicode string
- SAM_INFO (sam logon/logoff id info structure) :
Note: presumably, the return credentials is supposedly for the server to
verify that the credential chain hasn't been compromised.
CLNT_INFO2 client identification/authentication info
VOID* pointer to return credentials.
CRED return credentials - ignored.
UINT16 logon level
UINT16 switch value
switch (switch_value)
case 1:
{
ID_INFO_1 id_info_1;
}
- GID (group id info) :
UINT32 group id
UINT32 user attributes (only used by NT 3.1 and 3.51)
- DOM_REF (domain reference info) :
VOID* undocumented buffer pointer.
UINT32 num referenced domains?
VOID* undocumented domain name buffer pointer.
UINT32 32 - max number of entries
UINT32 4 - num referenced domains?
UNIHDR2 domain name unicode string header
UNIHDR2[num_ref_doms-1] referenced domain unicode string headers
UNISTR domain name unicode string
DOM_SID[num_ref_doms] referenced domain SIDs
- DOM_INFO (domain info, levels 3 and 5 are the same)) :
UINT8[] ??? padding to get 4-byte alignment with start of SMB header
UINT16 domain name string length * 2
UINT16 domain name string length * 2
VOID* undocumented domain name string buffer pointer
VOID* undocumented domain SID string buffer pointer
UNISTR2 domain name (unicode string)
DOM_SID domain SID
- USER_INFO (user logon info) :
Note: it would be nice to know what the 16 byte user session key is for.
NTTIME logon time
NTTIME logoff time
NTTIME kickoff time
NTTIME password last set time
NTTIME password can change time
NTTIME password must change time
UNIHDR username unicode string header
UNIHDR user's full name unicode string header
UNIHDR logon script unicode string header
UNIHDR profile path unicode string header
UNIHDR home directory unicode string header
UNIHDR home directory drive unicode string header
UINT16 logon count
UINT16 bad password count
UINT32 User ID
UINT32 Group ID
UINT32 num groups
VOID* undocumented buffer pointer to groups.
UINT32 user flags
char[16] user session key
UNIHDR logon server unicode string header
UNIHDR logon domain unicode string header
VOID* undocumented logon domain id pointer
char[40] 40 undocumented padding bytes. future expansion?
UINT32 0 - num_other_sids?
VOID* NULL - undocumented pointer to other domain SIDs.
UNISTR2 username unicode string
UNISTR2 user's full name unicode string
UNISTR2 logon script unicode string
UNISTR2 profile path unicode string
UNISTR2 home directory unicode string
UNISTR2 home directory drive unicode string
UINT32 num groups
GID[num_groups] group info
UNISTR2 logon server unicode string
UNISTR2 logon domain unicode string
DOM_SID domain SID
DOM_SID[num_sids] other domain SIDs?
- SH_INFO_1_PTR (pointers to level 1 share info strings):
Note: see cifsrap2.txt section5, page 10.
0 for shi1_type indicates a Disk.
1 for shi1_type indicates a Print Queue.
2 for shi1_type indicates a Device.
3 for shi1_type indicates an IPC pipe.
0x8000 0000 (top bit set in shi1_type) indicates a hidden share.
VOID* shi1_netname - pointer to net name
UINT32 shi1_type - type of share. 0 - undocumented.
VOID* shi1_remark - pointer to comment.
- SH_INFO_1_STR (level 1 share info strings) :
UNISTR2 shi1_netname - unicode string of net name
UNISTR2 shi1_remark - unicode string of comment.
- SHARE_INFO_1_CTR :
share container with 0 entries:
UINT32 0 - EntriesRead
UINT32 0 - Buffer
share container with > 0 entries:
UINT32 EntriesRead
UINT32 non-zero - Buffer
UINT32 EntriesRead
SH_INFO_1_PTR[EntriesRead] share entry pointers
SH_INFO_1_STR[EntriesRead] share entry strings
UINT8[] padding to get unicode string 4-byte
aligned with start of the SMB header.
UINT32 EntriesRead
UINT32 0 - padding
- SERVER_INFO_101 :
Note: see cifs6.txt section 6.4 - the fields described therein will be
of assistance here. for example, the type listed below is the
same as fServerType, which is described in 6.4.1.
SV_TYPE_WORKSTATION 0x00000001 All workstations
SV_TYPE_SERVER 0x00000002 All servers
SV_TYPE_SQLSERVER 0x00000004 Any server running with SQL
server
SV_TYPE_DOMAIN_CTRL 0x00000008 Primary domain controller
SV_TYPE_DOMAIN_BAKCTRL 0x00000010 Backup domain controller
SV_TYPE_TIME_SOURCE 0x00000020 Server running the timesource
service
SV_TYPE_AFP 0x00000040 Apple File Protocol servers
SV_TYPE_NOVELL 0x00000080 Novell servers
SV_TYPE_DOMAIN_MEMBER 0x00000100 Domain Member
SV_TYPE_PRINTQ_SERVER 0x00000200 Server sharing print queue
SV_TYPE_DIALIN_SERVER 0x00000400 Server running dialin service.
SV_TYPE_XENIX_SERVER 0x00000800 Xenix server
SV_TYPE_NT 0x00001000 NT server
SV_TYPE_WFW 0x00002000 Server running Windows for
SV_TYPE_SERVER_NT 0x00008000 Windows NT non DC server
SV_TYPE_POTENTIAL_BROWSER 0x00010000 Server that can run the browser
service
SV_TYPE_BACKUP_BROWSER 0x00020000 Backup browser server
SV_TYPE_MASTER_BROWSER 0x00040000 Master browser server
SV_TYPE_DOMAIN_MASTER 0x00080000 Domain Master Browser server
SV_TYPE_LOCAL_LIST_ONLY 0x40000000 Enumerate only entries marked
"local"
SV_TYPE_DOMAIN_ENUM 0x80000000 Enumerate Domains. The pszServer
and pszDomain parameters must be
NULL.
UINT32 500 - platform_id
VOID* pointer to name
UINT32 5 - major version
UINT32 4 - minor version
UINT32 type (SV_TYPE_... bit field)
VOID* pointer to comment
UNISTR2 sv101_name - unicode string of server name
UNISTR2 sv_101_comment - unicode string of server comment.
UINT8[] padding to get unicode string 4-byte
aligned with start of the SMB header.
3) MSRPC over Transact Named Pipe
---------------------------------
For details on the SMB Transact Named Pipe, see cifs6.txt
3.1) MSRPC Pipes
----------------
The MSRPC is conducted over an SMB Transact Pipe with a name of "\PIPE\".
You must first obtain a 16 bit file handle, by sending a SMBopenX with the
pipe name "\PIPE\srvsvc" for example. You can then perform an SMB Trans,
and must carry out an SMBclose on the file handle once you are finished.
Trans Requests must be sent with two setup UINT16s, no UINT16 params (none
known about), and UINT8 data parameters sufficient to contain the MSRPC
header, and MSRPC data. The first UINT16 setup parameter must be either
0x0026 to indicate an RPC, or 0x0001 to indicate Set Named Pipe Handle
state. The second UINT16 parameter must be the file handle for the pipe,
obtained above.
The Data section for an API Command of 0x0026 (RPC pipe) in the Trans
Request is the RPC Header, followed by the RPC Data. The Data section for
an API Command of 0x0001 (Set Named Pipe Handle state) is two bytes. The
only value seen for these two bytes is 0x00 0x43.
MSRPC Responses are sent as response data inside standard SMB Trans
responses, with the MSRPC Header, MSRPC Data and MSRPC tail.
It is suspected that the Trans Requests will need to be at least 2-byte
aligned (probably 4-byte). This is standard practice for SMBs. It is also
independent of the observed 4-byte alignments with the start of the MSRPC
header, including the 4-byte alignment between the MSRPC header and the
MSRPC data.
First, an SMBtconX connection is made to the IPC$ share. The connection
must be made using encrypted passwords, not clear-text. Then, an SMBopenX
is made on the pipe. Then, a Set Named Pipe Handle State must be sent,
after which the pipe is ready to accept API commands. Lastly, and SMBclose
is sent.
To be resolved:
lkcl/01nov97 there appear to be two additional bytes after the null-
terminated \PIPE\ name for the RPC pipe. Values seen so far are
listed below:
initial SMBopenX request: RPC API command 0x26 params:
"\\PIPE\\lsarpc" 0x65 0x63; 0x72 0x70; 0x44 0x65;
"\\PIPE\\srvsvc" 0x73 0x76; 0x4E 0x00; 0x5C 0x43;
3.2) Header
-----------
[section to be rewritten, following receipt of work by Duncan Stansfield]
Interesting note: if you set packed data representation to 0x0100 0000
then all 4-byte and 2-byte word ordering is turned around!
The start of each of the NTLSA and NETLOGON named pipes begins with:
00 UINT8 5 - RPC major version
01 UINT8 0 - RPC minor version
02 UINT8 2 - RPC response packet
03 UINT8 3 - (FirstFrag bit-wise or with LastFrag)
04 UINT32 0x1000 0000 - packed data representation
08 UINT16 fragment length - data size (bytes) inc header and tail.
0A UINT16 0 - authentication length
0C UINT32 call identifier. matches 12th UINT32 of incoming RPC data.
10 UINT32 allocation hint - data size (bytes) minus header and tail.
14 UINT16 0 - presentation context identifier
16 UINT8 0 - cancel count
17 UINT8 in replies: 0 - reserved; in requests: opnum - see #defines.
18 ...... start of data (goes on for allocation_hint bytes)
RPC_Packet for request, response, bind and bind acknowledgement.
{
UINT8 versionmaj # reply same as request (0x05)
UINT8 versionmin # reply same as request (0x00)
UINT8 type # one of the MSRPC_Type enums
UINT8 flags # reply same as request (0x00 for Bind, 0x03 for Request)
UINT32 representation # reply same as request (0x00000010)
UINT16 fraglength # the length of the data section of the SMB trans packet
UINT16 authlength
UINT32 callid # call identifier. (e.g. 0x00149594)
* stub USE TvPacket # the remainder of the packet depending on the "type"
}
# the interfaces are numbered. as yet I haven't seen more than one interface
# used on the same pipe name
# srvsvc
# abstract (0x4B324FC8, 0x01D31670, 0x475A7812, 0x88E16EBF, 0x00000003)
# transfer (0x8A885D04, 0x11C91CEB, 0x0008E89F, 0x6048102B, 0x00000002)
RPC_Iface RW
{
UINT8 byte[16] # 16 bytes of number
UINT32 version # the interface number
}
# the remainder of the packet after the header if "type" was Bind
# in the response header, "type" should be BindAck
RPC_ReqBind RW
{
UINT16 maxtsize # maximum transmission fragment size (0x1630)
UINT16 maxrsize # max receive fragment size (0x1630)
UINT32 assocgid # associated group id (0x0)
UINT32 numelements # the number of elements (0x1)
UINT16 contextid # presentation context identifier (0x0)
UINT8 numsyntaxes # the number of syntaxes (has always been 1?)(0x1)
UINT8[] # 4-byte alignment padding, against SMB header
* abstractint USE RPC_Iface # num and vers. of interface client is using
* transferint USE RPC_Iface # num and vers. of interface to use for replies
}
RPC_Address RW
{
UINT16 length # length of the string including null terminator
* port USE string # the string above in single byte, null terminated form
}
# the response to place after the header in the reply packet
RPC_ResBind RW
{
UINT16 maxtsize # same as request
UINT16 maxrsize # same as request
UINT32 assocgid # zero
* secondaddr USE RPC_Address # the address string, as described earlier
UINT8[] # 4-byte alignment padding, against SMB header
UINT8 numresults # the number of results (0x01)
UINT8[] # 4-byte alignment padding, against SMB header
UINT16 result # result (0x00 = accept)
UINT16 reason # reason (0x00 = no reason specified)
* transfersyntax USE RPC_Iface # the transfer syntax from the request
}
# the remainder of the packet after the header for every other other
# request
RPC_ReqNorm RW
{
UINT32 allochint # the size of the stub data in bytes
UINT16 prescontext # presentation context identifier (0x0)
UINT16 opnum # operation number (0x15)
* stub USE TvPacket # a packet dependent on the pipe name
# (probably the interface) and the op number)
}
# response to a request
RPC_ResNorm RW
{
UINT32 allochint # size of the stub data in bytes
UINT16 prescontext # presentation context identifier (same as request)
UINT8 cancelcount # cancel count? (0x0)
UINT8 reserved # 0 - one byte padding
* stub USE TvPacket # the remainder of the reply
}
3.3) Tail
---------
The end of each of the NTLSA and NETLOGON named pipes ends with:
...... end of data
UINT32 return code
3.4 RPC Bind / Bind Ack
-----------------------
RPC Binds are the process of associating an RPC pipe (e.g \PIPE\lsarpc)
with a "transfer syntax" (see RPC_Iface structure). The purpose for doing
this is unknown.
Note: The RPC_ResBind SMB Transact request is sent with two uint16 setup
parameters. The first is 0x0026; the second is the file handle
returned by the SMBopenX Transact response.
Note: The RPC_ResBind members maxtsize, maxrsize and assocgid are the
same in the response as the same members in the RPC_ReqBind. The
RPC_ResBind member transfersyntax is the same in the response as
the
Note: The RPC_ResBind response member secondaddr contains the name
of what is presumed to be the service behind the RPC pipe. The
mapping identified so far is:
initial SMBopenX request: RPC_ResBind response:
"\\PIPE\\srvsvc" "\\PIPE\\ntsvcs"
"\\PIPE\\samr" "\\PIPE\\lsass"
"\\PIPE\\lsarpc" "\\PIPE\\lsass"
"\\PIPE\\wkssvc" "\\PIPE\\wksvcs"
"\\PIPE\\NETLOGON" "\\PIPE\\NETLOGON"
Note: The RPC_Packet fraglength member in both the Bind Request and Bind
Acknowledgment must contain the length of the entire RPC data,
including the RPC_Packet header.
Request:
RPC_Packet
RPC_ReqBind
Response:
RPC_Packet
RPC_ResBind
4) NTLSA Transact Named Pipe
----------------------------
The sequence of actions taken on this pipe are:
- Establish a connection to the IPC$ share (SMBtconX). use encrypted passwords.
- Open an RPC Pipe with the name "\\PIPE\\lsarpc". Store the file handle.
- Using the file handle, send a Set Named Pipe Handle state to 0x4300.
- Send an LSA Open Policy request. Store the Policy Handle.
- Using the Policy Handle, send LSA Query Info Policy requests, etc.
- Using the Policy Handle, send an LSA Close.
- Close the IPC$ share.
Defines for this pipe, identifying the query are:
- LSA Open Policy: 0x2c
- LSA Query Info Policy: 0x07
- LSA Enumerate Trusted Domains: 0x0d
- LSA Open Secret: 0xff
- LSA Lookup SIDs: 0xfe
- LSA Lookup Names: 0xfd
- LSA Close: 0x00
4.1) LSA Open Policy
--------------------
Note: The policy handle can be anything you like.
Request:
VOID* buffer pointer
UNISTR2 server name - unicode string starting with two '\'s
OBJ_ATTR object attributes
UINT32 1 - desired access
Response:
POL_HND LSA policy handle
return 0 - indicates success
4.2) LSA Query Info Policy
--------------------------
Note: The info class in response must be the same as that in the request.
Request:
POL_HND LSA policy handle
UINT16 info class (also a policy handle?)
Response:
VOID* undocumented buffer pointer
UINT16 info class (same as info class in request).
switch (info class)
case 3:
case 5:
{
DOM_INFO domain info, levels 3 and 5 (are the same).
}
return 0 - indicates success
4.3) LSA Enumerate Trusted Domains
----------------------------------
Request:
no extra data
Response:
UINT32 0 - enumeration context
UINT32 0 - entries read
UINT32 0 - trust information
return 0x8000 001a - "no trusted domains" success code
4.4) LSA Open Secret
--------------------
Request:
no extra data
Response:
UINT32 0 - undocumented
UINT32 0 - undocumented
UINT32 0 - undocumented
UINT32 0 - undocumented
UINT32 0 - undocumented
return 0x0C00 0034 - "no such secret" success code
4.5) LSA Close
--------------
Request:
POL_HND policy handle to be closed
Response:
POL_HND 0s - closed policy handle (all zeros)
return 0 - indicates success
4.6) LSA Lookup SIDS
--------------------
Note: num_entries in response must be same as num_entries in request.
Request:
POL_HND LSA policy handle
UINT32 num_entries
VOID* undocumented domain SID buffer pointer
VOID* undocumented domain name buffer pointer
VOID*[num_entries] undocumented domain SID pointers to be looked up.
DOM_SID[num_entries] domain SIDs to be looked up.
char[16] completely undocumented 16 bytes.
Response:
DOM_REF domain reference response
UINT32 num_entries (listed above)
VOID* undocumented buffer pointer
UINT32 num_entries (listed above)
DOM_SID2[num_entries] domain SIDs (from Request, listed above).
UINT32 num_entries (listed above)
return 0 - indicates success
4.7) LSA Lookup Names
---------------------
Note: num_entries in response must be same as num_entries in request.
Request:
POL_HND LSA policy handle
UINT32 num_entries
UINT32 num_entries
VOID* undocumented domain SID buffer pointer
VOID* undocumented domain name buffer pointer
NAME[num_entries] names to be looked up.
char[] undocumented bytes - falsely translated SID structure?
Response:
DOM_REF domain reference response
UINT32 num_entries (listed above)
VOID* undocumented buffer pointer
UINT32 num_entries (listed above)
DOM_RID[num_entries] domain SIDs (from Request, listed above).
UINT32 num_entries (listed above)
return 0 - indicates success
5) NETLOGON rpc Transact Named Pipe
-----------------------------------
The sequence of actions taken on this pipe are:
- Establish a connection to the IPC$ share (SMBtconX). use encrypted passwords.
- Open an RPC Pipe with the name "\\PIPE\\NETLOGON". Store the file handle.
- Using the file handle, send a Set Named Pipe Handle state to 0x4300.
- Create Client Challenge. Send LSA Request Challenge. Store Server Challenge.
- Calculate Session Key. Send an LSA Auth 2 Challenge. Store Auth2 Challenge.
- Calc/Verify Client Creds. Send LSA Srv PW Set. Calc/Verify Server Creds.
- Calc/Verify Client Creds. Send LSA SAM Logon . Calc/Verify Server Creds.
- Calc/Verify Client Creds. Send LSA SAM Logoff. Calc/Verify Server Creds.
- Close the IPC$ share.
Defines for this pipe, identifying the query are:
- LSA Request Challenge: 0x04
- LSA Server Password Set: 0x06
- LSA SAM Logon: 0x02
- LSA SAM Logoff: 0x03
- LSA Auth 2: 0x0f
- LSA Logon Control: 0x0e
5.1) LSA Request Challenge
--------------------------
Note: logon server name starts with two '\' characters and is upper case.
Note: logon client is the machine, not the user.
Note: the initial LanManager password hash, against which the challenge
is issued, is the machine name itself (lower case). there will be
calls issued (LSA Server Password Set) which will change this, later.
refusing these calls allows you to always deal with the same password
(i.e the LM# of the machine name in lower case).
Request:
VOID* undocumented buffer pointer
UNISTR2 logon server unicode string
UNISTR2 logon client unicode string
char[8] client challenge
Response:
char[8] server challenge
return 0 - indicates success
5.2) LSA Authenticate 2
-----------------------
Note: in between request and response, calculate the client credentials,
and check them against the client-calculated credentials (this
process uses the previously received client credentials).
Note: neg_flags in the response is the same as that in the request.
Note: you must take a copy of the client-calculated credentials received
here, because they will be used in subsequent authentication packets.
Request:
LOG_INFO client identification info
char[8] client-calculated credentials
UINT8[] padding to 4-byte align with start of SMB header.
UINT32 neg_flags - negotiated flags (usual value is 0x0000 01ff)
Response:
char[8] server credentials.
UINT32 neg_flags - same as neg_flags in request.
return 0 - indicates success. failure value unknown.
5.3) LSA Server Password Set
----------------------------
Note: the new password is suspected to be a DES encryption using the old
password to generate the key.
Note: in between request and response, calculate the client credentials,
and check them against the client-calculated credentials (this
process uses the previously received client credentials).
Note: the server credentials are constructed from the client-calculated
credentials and the client time + 1 second.
Note: you must take a copy of the client-calculated credentials received
here, because they will be used in subsequent authentication packets.
Request:
CLNT_INFO client identification/authentication info
char[] new password - undocumented.
Response:
CREDS server credentials. server time stamp appears to be ignored.
return 0 - indicates success; 0xC000 006a indicates failure
5.4) LSA SAM Logon
------------------
Note: valid_user is True iff the username and password hash are valid for
the requested domain.
Request:
SAM_INFO sam_id structure
Response:
VOID* undocumented buffer pointer
CREDS server credentials. server time stamp appears to be ignored.
if (valid_user)
{
UINT16 3 - switch value indicating USER_INFO structure.
VOID* non-zero - pointer to USER_INFO structure
USER_INFO user logon information
UINT32 1 - Authoritative response; 0 - Non-Auth?
return 0 - indicates success
}
else
{
UINT16 0 - switch value. value to indicate no user presumed.
VOID* 0x0000 0000 - indicates no USER_INFO structure.
UINT32 1 - Authoritative response; 0 - Non-Auth?
return 0xC000 0064 - NT_STATUS_NO_SUCH_USER.
}
5.5) LSA SAM Logoff
--------------------
Note: presumably, the SAM_INFO structure is validated, and a (currently
undocumented) error code returned if the Logoff is invalid.
Request:
SAM_INFO sam_id structure
Response:
VOID* undocumented buffer pointer
CREDS server credentials. server time stamp appears to be ignored.
return 0 - indicates success. undocumented failure indication.
6) \\MAILSLOT\NET\NTLOGON
-------------------------
Note: mailslots will contain a response mailslot, to which the response
should be sent. the target NetBIOS name is REQUEST_NAME<20>, where
REQUEST_NAME is the name of the machine that sent the request.
6.1) Query for PDC
------------------
Note: NTversion, LMNTtoken, LM20token in response are the same as those
given in the request.
Request:
UINT16 0x0007 - Query for PDC
STR machine name
STR response mailslot
UINT8[] padding to 2-byte align with start of mailslot.
UNISTR machine name
UINT32 NTversion
UINT16 LMNTtoken
UINT16 LM20token
Response:
UINT16 0x000A - Respose to Query for PDC
STR machine name (in uppercase)
UINT8[] padding to 2-byte align with start of mailslot.
UNISTR machine name
UNISTR domain name
UINT32 NTversion (same as received in request)
UINT16 LMNTtoken (same as received in request)
UINT16 LM20token (same as received in request)
6.2) SAM Logon
--------------
Note: machine name in response is preceded by two '\' characters.
Note: NTversion, LMNTtoken, LM20token in response are the same as those
given in the request.
Note: user name in the response is presumably the same as that in the request.
Request:
UINT16 0x0012 - SAM Logon
UINT16 request count
UNISTR machine name
UNISTR user name
STR response mailslot
UINT32 alloweable account
UINT32 domain SID size
char[sid_size] domain SID, of sid_size bytes.
UINT8[] ???? padding to 4? 2? -byte align with start of mailslot.
UINT32 NTversion
UINT16 LMNTtoken
UINT16 LM20token
Response:
UINT16 0x0013 - Response to SAM Logon
UNISTR machine name
UNISTR user name - workstation trust account
UNISTR domain name
UINT32 NTversion
UINT16 LMNTtoken
UINT16 LM20token
7) SRVSVC Transact Named Pipe
-----------------------------
Defines for this pipe, identifying the query are:
- Net Share Enum : 0x0f
- Net Server Get Info : 0x15
7.1) Net Share Enum
------------------
Note: share level and switch value in the response are presumably the
same as those in the request.
Note: cifsrap2.txt (section 5) may be of limited assistance here.
Request:
VOID* pointer (to server name?)
UNISTR2 server name
UINT8[] padding to get unicode string 4-byte aligned
with the start of the SMB header.
UINT32 share level
UINT32 switch value
VOID* pointer to SHARE_INFO_1_CTR
SHARE_INFO_1_CTR share info with 0 entries
UINT32 preferred maximum length (0xffff ffff)
Response:
UINT32 share level
UINT32 switch value
VOID* pointer to SHARE_INFO_1_CTR
SHARE_INFO_1_CTR share info (only added if share info ptr is non-zero)
return 0 - indicates success
7.2) Net Server Get Info
------------------
Note: level is the same value as in the request.
Request:
UNISTR2 server name
UINT32 switch level
Response:
UINT32 switch level
VOID* pointer to SERVER_INFO_101
SERVER_INFO_101 server info (only added if server info ptr is non-zero)
return 0 - indicates success
Appendix
--------
A1) Cryptographic side of NT Domain Authentication
--------------------------------------------------
A1.1) Definitions
-----------------
Add(A1,A2): Intel byte ordered addition of corresponding 4 byte words
in arrays A1 and A2
E(K,D): DES ECB encryption of 8 byte data D using 7 byte key K
lmowf(): Lan man hash
ntowf(): NT hash
PW: md4(machine_password) == md4(lsadump $machine.acc) ==
pwdump(machine$) (initially) == md4(lmowf(unicode(machine)))
ARC4(K,Lk,D,Ld): ARC4 encryption of data D of length Ld with key K of
length Lk
v[m..n(,l)]: subset of v from bytes m to n, optionally padded with
zeroes to length l
Cred(K,D): E(K[7..7,7],E(K[0..6],D)) computes a credential
Time(): 4 byte current time
Cc,Cs: 8 byte client and server challenges Rc,Rs: 8 byte client and
server credentials
A1.2) Protocol
--------------
C->S ReqChal,Cc S->C Cs
C & S compute session key Ks = E(PW[9..15],E(PW[0..6],Add(Cc,Cs)))
C: Rc = Cred(Ks,Cc) C->S Authenticate,Rc S: Rs = Cred(Ks,Cs),
assert(Rc == Cred(Ks,Cc)) S->C Rs C: assert(Rs == Cred(Ks,Cs))
On joining the domain the client will optionally attempt to change its
password and the domain controller may refuse to update it depending
on registry settings. This will also occur weekly afterwards.
C: Tc = Time(), Rc' = Cred(Ks,Rc+Tc) C->S ServerPasswordSet,Rc',Tc,
arc4(Ks[0..7,16],lmowf(randompassword()) C: Rc = Cred(Ks,Rc+Tc+1) S:
assert(Rc' == Cred(Ks,Rc+Tc)), Ts = Time() S: Rs' = Cred(Ks,Rs+Tc+1)
S->C Rs',Ts C: assert(Rs' == Cred(Ks,Rs+Tc+1)) S: Rs = Rs'
User: U with password P wishes to login to the domain (incidental data
such as workstation and domain omitted)
C: Tc = Time(), Rc' = Cred(Ks,Rc+Tc) C->S NetLogonSamLogon,Rc',Tc,U,
arc4(Ks[0..7,16],16,ntowf(P),16), arc4(Ks[0..7,16],16,lmowf(P),16) S:
assert(Rc' == Cred(Ks,Rc+Tc)) assert(passwords match those in SAM) S:
Ts = Time()
S->C Cred(Ks,Cred(Ks,Rc+Tc+1)),userinfo(logon script,UID,SIDs,etc) C:
assert(Rs == Cred(Ks,Cred(Rc+Tc+1)) C: Rc = Cred(Ks,Rc+Tc+1)
A1.3) Comments
--------------
On first joining the domain the session key could be computed by
anyone listening in on the network as the machine password has a well
known value. Until the machine is rebooted it will use this session
key to encrypt NT and LM one way functions of passwords which are
password equivalents. Any user who logs in before the machine has been
rebooted a second time will have their password equivalent exposed. Of
course the new machine password is exposed at this time anyway.
None of the returned user info such as logon script, profile path and
SIDs *appear* to be protected by anything other than the TCP checksum.
The server time stamps appear to be ignored.
The client sends a ReturnAuthenticator in the SamLogon request which I
can't find a use for. However its time is used as the timestamp
returned by the server.
The password OWFs should NOT be sent over the network reversibly
encrypted. They should be sent using ARC4(Ks,md4(owf)) with the server
computing the same function using the owf values in the SAM.
A2) SIDs and RIDs
-----------------
SIDs and RIDs are well documented elsewhere.
A SID is an NT Security ID (see DOM_SID structure). They are of the form:
S-revision-NN-SubAuth1-SubAuth2-SubAuth3...
S-revision-0xNNNNNNNNNNNN-SubAuth1-SubAuth2-SubAuth3...
currently, the SID revision is 1.
The Sub-Authorities are known as Relative IDs (RIDs).
A2.1) Well-known SIDs
---------------------
A2.1.1) Universal well-known SIDs
---------------------------------
Null SID S-1-0-0
World S-1-1-0
Local S-1-2-0
Creator Owner ID S-1-3-0
Creator Group ID S-1-3-1
Creator Owner Server ID S-1-3-2
Creator Group Server ID S-1-3-3
(Non-unique IDs) S-1-4
A2.1.2) NT well-known SIDs
--------------------------
NT Authority S-1-5
Dialup S-1-5-1
Network S-1-5-2
Batch S-1-5-3
Interactive S-1-5-4
Service S-1-5-6
AnonymousLogon S-1-5-7 (aka null logon session)
Proxy S-1-5-8
ServerLogon S-1-5-8 (aka domain controller account)
(Logon IDs) S-1-5-5-X-Y
(NT non-unique IDs) S-1-5-0x15-...
(Built-in domain) s-1-5-0x20
A2.2) Well-known RIDS
---------------------
A RID is a sub-authority value, as part of either a SID, or in the case
of Group RIDs, part of the DOM_GID structure, in the USER_INFO_1
structure, in the LSA SAM Logon response.
A2.2.1) Well-known RID users
----------------------------
DOMAIN_USER_RID_ADMIN 0x0000 01F4
DOMAIN_USER_RID_GUEST 0x0000 01F5
A2.2.2) Well-known RID groups
----------------------------
DOMAIN_GROUP_RID_ADMINS 0x0000 0200
DOMAIN_GROUP_RID_USERS 0x0000 0201
DOMAIN_GROUP_RID_GUESTS 0x0000 0202
A2.2.3) Well-known RID aliases
------------------------------
DOMAIN_ALIAS_RID_ADMINS 0x0000 0220
DOMAIN_ALIAS_RID_USERS 0x0000 0221
DOMAIN_ALIAS_RID_GUESTS 0x0000 0222
DOMAIN_ALIAS_RID_POWER_USERS 0x0000 0223
DOMAIN_ALIAS_RID_ACCOUNT_OPS 0x0000 0224
DOMAIN_ALIAS_RID_SYSTEM_OPS 0x0000 0225
DOMAIN_ALIAS_RID_PRINT_OPS 0x0000 0226
DOMAIN_ALIAS_RID_BACKUP_OPS 0x0000 0227
DOMAIN_ALIAS_RID_REPLICATOR 0x0000 0228