Microsoft Networks SMB FILE SHARING PROTOCOL Document Version 6.0p January 1, 1996 Microsoft Corporatio Introduction 5 Resource Sharing Connections 5 Message Format 7 Sample Messge Flow 8 SMB Protocol Dialects 8 Message Transport 9 Reliable NetBIOS Transports 9 Connectionless IPX Transport 10 Naming On Ipx 12 Opportunistic Locks 12 Exclusive Oplocks 13 Batch Oplocks 14 Level II Oplocks 15 NAMED PIPES 15 Named Pipe Features 15 SMB MESSAGES AND FORMATS 16 SMB Header 16 Flags field 17 Flags2 Field 17 Tid Field 18 Pid Field 18 Mid Field 18 Status Field 19 Timeouts 19 Data Buffer (Buffer) and String Formats 19 Time And Date Encoding 20 Access Mode Encoding 20 File Attribute Encoding 21 “ANDX” SMB Messages 21 SMB MESSAGES 22 Valid SMB Messages by Negotiated Dialect 22 NEGOTIATE: Negotiate Protocol 23 SESSION_SETUP_ANDX: Session Setup And X 26 LOGOFF_ANDX: User Logoff And X 29 TREE_CONNECT: Tree Connect 29 TREE_CONNECT_ANDX: Tree Connect And X 30 TREE_DISCONNECT: Tree Disconnect 31 CREATE_DIRECTORY: Create Directory 31 DELETE_DIRECTORY: Delete Directory 32 CHECK_DIRECTORY: Check Directory 32 OPEN: Open File 32 CREATE: Create File 34 CLOSE: Close File 34 FLUSH: Flush File 35 DELETE: Delete File 35 RENAME: Rename File 36 QUERY_INFORMATION: Get File Attributes 37 SET_INFORMATION: Set File Attributes 37 READ: Read File 37 WRITE: Write Bytes 38 LOCK_BYTE_RANGE: Lock Bytes 39 UNLOCK_BYTE_RANGE: Unlock Bytes 40 CREATE_TEMPORARY: Create Temporary File 40 CREATE_NEW: Create File 40 PROCESS_EXIT: Process Exit 41 SEEK: Seek in File 41 SMB_QUERY_INFORMATION_DISK: Get Disk Attributes 42 SEARCH: Search Directory 43 OPEN_PRINT_FILE: Create Print Spool file 44 WRITE_PRINT_FILE: Write to Print File 45 CLOSE_PRINT_FILE: Close and Spool Print Job 45 GET_PRINT_QUEUE: Get Printer Queue Entries 45 LOCK_AND_READ: Lock and Read Bytes 47 WRITE_AND_UNLOCK: Write Bytes and Unlock Range 47 READ_RAW: Read Raw 48 READ_MPX: Read Block Multiplex 50 WRITE_RAW: Write Raw Bytes 51 WRITE_MPX: Write Block Multiplex 53 SET_INFORMATION2: Set File Information 55 QUERY_INFORMATION2: Get File Information 55 LOCKING_ANDX: Lock or UnLock Bytes 55 MOVE: Rename File 58 COPY: Copy File 59 ECHO: Ping the Server 60 WRITE_AND_CLOSE: Write Bytes and Close File 60 OPEN_ANDX: Open File And X 62 NT_CREATE_ANDX: Create File 64 READ_ANDX: Read Data 65 WRITE_ANDX: Write Bytes to file or resource 66 TRANSACTIONS 68 SMB_COM_TRANSACTION and SMB_COM_TRANSACTION2 Formats 68 SMB_COM_NT_TRANSACTION Formats 70 Functional Description 71 SMB_COM_TRANSACTION Operations 74 Mail Slot Transaction Protocol 74 Named Pipe Transaction Protocol 74 CallNamedPipe 75 WaitNamedPipe 75 PeekNamedPipe 75 GetNamedPipeHandleState 76 SetNamedPipeHandleState 76 GetNamedPipeInfo 77 TransactNamedPipe 77 RawReadNamedPipe 78 RawWriteNamedPipe 78 SMB_COM_TRANSACTION2 Operations 78 TRANS2_OPEN2 78 TRANS2_FIND_FIRST2 81 SMB_INFO_STANDARD 82 SMB_INFO_QUERY_EA_SIZE 82 SMB_INFO_QUERY_EAS_FROM_LIST 82 SMB_FIND_FILE_DIRECTORY_INFO 83 SMB_FIND_FILE_FULL_DIRECTORY_INFO 83 SMB_FIND_FILE_BOTH_DIRECTORY_INFO 83 SMB_FIND_FILE_NAMES_INFO 83 TRANS2_FIND_NEXT2 84 TRANS2_QUERY_FS_INFORMATION 84 SMB_INFO_ALLOCATION 86 SMB_INFO_VOLUME 86 TRANS2_QUERY_PATH_INFORMATION 86 SMB_INFO_STANDARD & SMB_INFO_QUERY_EA_SIZE 86 SMB_INFO_QUERY_EAS_FROM_LIST & SMB_INFO_QUERY_ALL_EAS 87 SMB_INFO_IS_NAME_VALID 87 TRANS2_SET_PATH_INFORMATION 87 SMB_INFO_STANDARD & SMB_INFO_QUERY_EA_SIZE 88 SMB_INFO_QUERY_ALL_EAS 88 TRANS2_QUERY_FILE_INFORMATION 88 TRANS2_SET_FILE_INFORMATION 88 TRANS2_CREATE_DIRECTORY 89 SMB_COM_NT_TRANSACTION Operations 89 NT_TRANSACT_CREATE 90 NT_TRANSACT_IOCTL 90 NT_TRANSACT_SET_SECURITY_DESC 91 NT_TRANSACT_NOTIFY_CHANGE 91 NT_TRANSACT_QUERY_SECURITY_DESC 92 NT_CANCEL: Cancel request 92 FIND_CLOSE2: Close Search 92 SMB COMMAND CODES 93 ERROR CODES AND CLASSES 94 Introduction This document describes the Lan Manager Server Message Block (SMB) file sharing protocol. Client systems use this protocol to request file, print, and communications service from server systems over a network. There are several different versions and sub-versions of this protocol, a particular version is referred to as a dialect. When two machines first come into network contact they negotiate the dialect to be used. For example, two NT systems would agree to use the NT-specific protocol dialect, while a Windows For Workgroups client communicating with an NT server might negotiate a Windows For Workgroups dialect. Different dialects can include both new messages as well as changes to the fields and semantics of existing messages in other dialects. Resource Sharing Connections Each server makes a set of resources available to clients on the network. A resource being shared may be a directory tree, named pipe, printer, etc. So far as clients are concerned, the server has no storage or service dependencies on any other servers; a client considers the server to be the sole provider of the file (or other resource) being accessed. The SMB protocol requires server authentication of users before file accesses are allowed, and each server authenticates its own users. A client system must send authentication information to the server before the server will allow access to its resources. The SMB protocol defines two methods which can be selected by the server for security: share level and user level: A share level server makes some directory on a disk device (or other resource) available. An optional password may be required to gain access. Thus any user on the network who knows the name of the server, the name of the resource and the password has access to the resource. Share level security servers may use different passwords for the same shared resource with different passwords allowing different levels of access. Windows for Workgroups and Windows 95 servers, for instance, implement the share level security model. A user level server makes some directory on a disk device (or other resource) available but in addition requires the client to provide a user name and corresponding user password to gain access. NT servers and LM/U servers implement this security model and do not support the share level model. User level servers are preferred over share level servers for any new server implementation, since corporations generally find user level servers easier to administer as employees come and go. When a user level server validates the account name and password presented by the client, an identifier representing that authenticated instance of the user is returned to the client in the Uid field of the response SMB. This Uid must be included in all further requests made on behalf of the user from that client. A share level server returns no useful information in the Uid field. The user level security model was added after the original dialect of the SMB protocol was issued, and subsequently some clients may not be capable of sending account name and passwords to the server. A server in user level security mode communicating with one of these clients will allow a client to connect to resources even if the client has not sent account name and password information: 1. If the client's computer name is identical to an account-name known on the server, and if the password supplied to connect to the shared resouce matches that account’s password, an implicit "user logon" will be performed using those values. If the above fails, the server may fail the request or assign a default account name of its choice. 2. The value of Uid in subsequent requests by the client will be ignored and all access will be validated assuming the account name selected above. The following examples illustrate a possible command line user interface for a server to offer a disk resource, and for a client to connect to and use that resource. a) NET SHARE The NET SHARE command, when executed on the server, specifies a directory name to be made available to clients on the network. A share name must be given, and this name is presented by clients wishing to access the directory. Examples: NET SHARE src=c:\dir1\src "bonzo" assigns password bonzo to all files within directory c:\dir1\src and its subdirectories with the share name src being the name used to connect to this resource. NET SHARE c=c:\ " " RO NET SHARE work=c:\work "flipper" RW offers read-only access to everything on the C drive. Offers read-write access to all files within the C:\work directory and its subdirectories. The above example is appropriate for servers operating as a share level server. A user level server would not require the permissions or password, since the combination of the client’s account name and specific access control lists on files is sufficient to govern access. b) NET USE Clients can gain access to one or more offered directories via the NET USE command. Once the NET USE command is issued the user can access the files freely without further special requirements. Examples: 1. NET USE d: \\Server1\src "bonzo" gains full access to the files and directories on Server1 matching the offer defined by the netname src with the password of bonzo. The user may now address files on Server1 c:\dir1\src by referencing d:. E.g. "type d:srcfile1.c". 2. NET USE e: \\Server1\c 3. NET USE f: \\Server1\work "flipper" Now any read request to any file on that node (drive c) is valid (e.g. "type e:\bin\foo.bat"). Read-write requests only succeed to files whose pathnames start with f: (e.g. "copy foo f:foo.tmp" copies foo to Server1 c:\work\foo.tmp). For user level servers, the client would not provide a password with the NET USE command. The client software must remember the drive identifier supplied with the NET USE request and associate it with the Tid value returned by the server in the SMB header. Subsequent requests using this Tid must include only the pathname relative to the connected subtree as the server treats the subtree as the root directory (virtual root). When the user references one of the remote drives, the client software looks through its list of drives for that node and includes the tree id associated with this drive in the Tid field of each request. Note that one shares a directory and all files underneath that directory are then affected. If a particu- lar file is within the range of multiple shares, connecting to any of the share ranges gains access to the file with the permissions specified for the offer named in the NET USE. The server will not check for nested directories with more restrictive permissions. Message Format Clients exchange messages with a server to access resources on that server. These messages are called Server Message Blocks (SMBs), and every SMB message has a common format: typedef unsigned char UCHAR; // 8 unsigned bits typedef unsigned short USHORT; // 16 unsigned bits typedef unsigned long ULONG; // 32 unsigned bits typedef struct { ULONG LowPart; LONG HighPart; } LARGE_INTEGER; // 64 bits of data typedef struct { ULONG LowTime; LONG HighTime; } TIME; typedef struct { UCHAR Protocol[4]; // Contains 0xFF,'SMB' UCHAR Command; // Command code union { struct { UCHAR ErrorClass; // Error class UCHAR Reserved; // Reserved for future use USHORT Error; // Error code } DosError; ULONG NtStatus; // NT-style 32-bit error code } Status; UCHAR Flags; // Flags USHORT Flags2; // More flags union { USHORT Pad[6]; // Ensure this section is 12 bytes struct { USHORT PidHigh; // High part of PID (NT Create And X) struct { ULONG HdrReserved; // Not used USHORT Sid; // Session ID USHORT SequenceNumber; // Sequence number } Connectionless; // IPX } }; USHORT Tid; // Tree identifier USHORT Pid; // Caller's process id USHORT Uid; // Unauthenticated user id USHORT Mid; // multiplex id UCHAR WordCount; // Count of parameter words USHORT ParameterWords[ WordCount ]; // The parameter words USHORT ByteCount; // Count of bytes UCHAR Buffer[ ByteCount ]; // The bytes } SMB_HEADER; All SMBs have identical format up to the ParameterWords fields. Different SMBs have a different number and interpretation of ParameterWords and Buffer. All reserved fields in the SMB header must be zero. All quantities are sent in native Intel format. Command is the operation code which this SMB is requesting, or responding to. Status.DosError.ErrorClass and Status.DosError.Error are set by the server and combine to give the error code of any failed server operation. If the client is capable of receiving 32 bit error returns, the status is returned in Status.NtStatus instead. When an error is returned, the server may choose to return only the header portion of the response SMB. Flags and Flags2 contain bits which, depending on the negotiated protocol dialect, indicate vairous client capabilities. PidHigh is used in the NtCreateAndX request SMB Connectionless. Sid, and Connectionless.SequenceNumber are used when the client to server connection is on a datagram oriented protocol such as IPX or UDP. StreamProtocol.SMBLength is used to frame this SMB when the client to server connection is on a byte stream protocol such as TCP. It is the entire length of the SMB from the initial 0xFF to the final byte. Tid identifies the subdirectory, or “tree”, on the server which the client is accessing. SMBs which do not reference a particular tree should set Tid to 0xFFFF Pid is the caller’s process id, and is generated by the client to uniquely identify a process within the client computer. Mid is reserved for multiplexing multiple messages on a single Virtual Circuit (VC). A response message will always contain the same value as the corresponding request message. Sample Messge Flow The following illustrates a typical message exchange for a client connecting to a user level server, opening a file, reading its data, closing the file, and disconnecting from the server. Client Command Server Response SMB_COM_NEGOTIATE Must be the first message sent by client to the server. Includes a list of SMB dialects supported by the client. Server response indicates which SMB dialect should be used. SMB_COM_SESSION_SETUP_ANDX Transmits the user’s name and credentials to the server for verification. Successful server response has Uid field set in SMB header used for subsequent SMBs on behalf of this user. SMB_COM_TREE_CONNECT Transmits the name of the disk share the client wants to access. Successful server response has Tid field set in SMB header used for subsequent SMBs referring to this resource. SMB_COM_OPEN Transmits the name of the file, relative to Tid, the client wants to open. Successful server response includes a file id (fid) the client should supply for subsequent operations on this file. SMB_COM_READ Client supplies Tid, fid, file offset, and number of bytes to read. Successful server response includes the requested file data SMB_COM_CLOSE Client closes the file represented by Tid and fid. Server responds with success code. SMB_COM_TREE_DISCONNECT Client disconnects from resource represented by Tid SMB Protocol Dialects The first message sent from an SMB client to an SMB server must be one whose Command field is SMB_COM_NEGOTIATE. The format of this client request includes an array of NULL terminated strings indicating the dialects of the SMB protocol which the client supports. The server compares this list against the list of dialects the server supports and returns the index of the chosen dialect in the response message. This is the list of SMB protocol dialects, ordered from least functional (earliest) version to most functional (most recent) version: Dialect Name Comment PC NETWORK PROGRAM 1.0 The original MSNET SMB protocol (otherwise known as the “core protocol” ) PCLAN1.0 Some versions of the original MSNET defined this as an alternate to the core protocol name MICROSOFT NETWORKS 1.03 This is used for the MS-NET 1.03 product. It defines Lock&Read, Write&Unlock, and a special version of raw read and raw write. MICROSOFT NETWORKS 3.0 This is the DOS LANMAN 1.0 specific protocol. It is equivilant to the LANMAN 1.0 protocol, except the server is required to map errors from the OS/2 error to an appropriate DOS error. LANMAN1.0 This is the first version of the full LANMAN 1.0 protocol LM1.2X002 This is the first version of the full LANMAN 2.0 protocol DOS LM1.2X002 This is the dos equivilant of the LM1.2X002 protocol. It is identical to the LM1.2X002 protocol, but the server will perform error mapping to appropriate DOS errors. DOS LANMAN2.1 DOS LANMAN2.1 LANMAN2.1 OS/2 LANMAN2.1 Windows for Workgroups 3.1a Windows for Workgroups Version 1.0 NT LM 0.12 The SMB protocol designed for NT. This has special SMBs which duplicate the NT semantics. SMB servers select the most recent version of the protocol known to both client and server. Any SMB server which supports dialects newer than the original core dialect must support all the messages and semantics of the dialects between the core dialect and the newer one. This is to say that a server which supports the NT LM 0.12 dialect must also support all of the messages of the previous 10 dialects. It is the client’s responsibility to ensure it only sends SMBs which are appropriate to the dialect negotiated. Message Transport Clients and servers exchange messages over either a reliable NetBIOS transport or a connectionless transport such as IPX. Reliable NetBIOS Transports The client and server can use NETBIOS to establish and maintain communications. The server ‘posts’ a name on the network and the client connects to that name. For compatibility with pre- Windows 95 and pre-Windows NT clients, a server’s NetBIOS name should comply with the standard DOS 8.3 format and be blank padded to the right. All NETBIOS-based SMB servers have a name whose 16-th character is 20 hex. When using such a reliable message-oriented transport, the SMB protocol makes no higher level attempts to ensure reliable sequenced delivery of messages between the client and server. The transport should have some mechanism to detect failures of either the client or server node, and to deliver such an indication to the client or server software so they can clean up state. When a reliable transport from a client terminates, all work in progress by that client is terminated and all resources open by that client are closed. The rules for reliable transport establishment and dissolution are: If a server receives a transport establishment request from a client with which it is already conversing, the server may terminate all other transport connections to that client. This is to recover from the situation where the client was suddenly rebooted and was unable to cleanly terminate its resource sharing activities with the server. A server may drop the transport connection to a client at any time if the client is generating malformed or illogical requests. However, wherever possible the server should first return an error code to the client indicating the cause of the abort. If a server gets a hard error on the transport (such as a send failure) the transport connection to that client may be aborted. A server may terminate the transport connection when the client has no open resources on the server, however, we recommend that the termination be performed only after some time has passed or if resouces are scarce on the server. This will help performance in that the transport connection will not need to be reestablished if activity soon begins anew. Client software is expected to be able to automatically reconnect to the server if this happens. Connectionless IPX Transport Unlike a traditional transport protocol, the connectionless SMB protocol is asymmetric. Wherever possible, processing overhead has been moved from the server to the client so that the server can scale to a large number of clients efficiently. For example, the server does not initiate retransmission of lost responses. It is entirely up to the client to resend the request in the case of lost packets in either direction. Five IPX sockets are used as follows: Socket Name Value Purpose SMB_SERVER_SOCKET 0x0550 SMB requests from clients SMB_NAME_SOCKET 0x0551 name claims and name query messages REDIR_SOCKET 0x0552 is used by the redirector for sending SMB requests and receiving SMB replies. MAILSLOT_SOCKET 0x0553 is used by the redirector and browser for mailslot datagrams. MESSENGER_SOCKET 0x0554 is used by the redirector to send messages from client to client (NetMessageBufferSend). The SMB header includes two fields specifically designed for use on IPX. Sid is the server's session ID and SequenceNumber is the message sequence number. The Sid value is generated by the server, and returned to the client in the Negotiate Protocol response. The client must use this Sid value in all future SMB exchanges with this server during this resource sharing session. SequenceNumber is supplied by the client. A valid SequenceNumber is either zero or one greater than the previous sequence number sent by the client. For unsequenced commands (i.e. SequenceNumber is 0) the redirector must use the Mid field to identify SMB responses. The redirector should take steps to generate relatively unique values for Mid for each request. In particular, the client must ensure that it never has two or more distinct requests outstanding to the server whose SequenceNumbers are 0 and whose Mids are identical. The maximum packet size for some IPX routers is 576 bytes including the IPX header. Because of this, the client must limit the size of the negotiated buffer size to 546 bytes when the server's network ID is not the same as the client's network ID. If desired, the client could dynamically determine the maximum packet size by sending echo SMBs to the server using various packet sizes and then selecting the largest size which worked correctly. Sequenced commands are used for operations which cause a state change on the server that cannot be repeated. For example, file open/close or record locking. Unsequenced commands are used for operations which can be performed as many times as necessary with the same result each time. For example, reading or writing to a disk file. The server maintains a small save area for each client to keep the response information from the previous sequenced command. Because the server has a limited amount of space available for this save area, the client must send all commands with a large response size as unsequenced. Such commands include file read and file search. If the response to a sequenced command is too large, the server will fail the request with a Status.DosError.ErrorClass set to SMB_ERR_CLASS_SERVER and Status.DosError.Error set to ERRerror. If the Sid value in incorrect, the server will fail the request with a Status.DosError.ErrorClass set to SMB_ERR_CLASS_SERVER and Status.DosError.Error set to SMB_ERR_BAD_SID. If the server has an SMB in progress which matches either SequenceNumber for sequenced commands or Mid for unsequenced commands, it will respond with Status.DosError.ErrorClass set to SMB_ERR_CLASS_SERVER and Status.DosError.Error set to SMB_ERR_WORKING. For sequenced commands, the server requires that the sequence numbers progress in order, S, S+1, S+2, ... The sequence number wraps to one (1) not zero. The wrap around progression is: 65534, 65535, 1, 2, ... Out of sequence commands are ignored by the server. The exceptions to the “large response requires unsequenced” rule are transaction SMBs. These SMBs are used both to retrieve bulk data from the server (EG: enumerate shares, enumerate servers, etc.) and to change the server's state (EG: add a new share, change file permissions, etc.) Transaction requests are also unusual because they can have a multiple part request and/or a multiple part response. For this reason, transactions are handled as a set of sequenced commands to the server. Each part of a request is sent as a sequenced command using the same Mid value and an increasing Seq value. The server responds to each request piece except the last one with a response indicating that the server is ready for the next piece. The last piece is responded to with the first piece of the result data. The client then sends a transaction secondary SMB with ParameterDisplacement set to the number of parameter bytes received so far and DataDisplacement set to the number of data bytes received so far and ParameterCount, ParameterOffset, DataCount, and DataOffset set to zero (0). The server responds with the next piece of the transaction result. The process is repeated until all of the response information has been received. When the transaction has been completed, the redirector must send another sequenced command (an echo SMB will do fine) to the server to allow the server to know that the final piece was received and that resources allocated to the transaction command may be released. The flow is as follows, where (S) is the SequenceNumber, (N) is the number of request packets to be sent from the client to the server, and (M) is the number of response packets to be sent by the server to the client: Client Server SMB(S) Transact ® OK (S) send more data [ repeat N-1 times: SMB(S+1) Transact secondary ® OK (S+1) send more data SMB(S+N-1) ] OK (S+N-1) transaction response (1) [ repeat M-1 times: SMB(S+N) Transact secondary ® OK (S+N) transaction response (2) SMB(S+N+M-2) Transact secondary ® OK (S+N+M-2] transaction response (M) ] SMB(S+N+M-1) Echo ® OK (S+N+M-1) echoed In order to allow the server to detect clients which have been powered off, have crashed, etc., the client must send commands to the server periodically. If nothing has been received from a client for awhile, the server will assume that the client is no longer running and disconnect the client. This includes closing any files that the client had open at the time and releasing any resources being used on behalf of the client. Clients should at least send an echo SMB to the server every four (4) minutes if there is nothing else to send. The server will disconnect clients after a configurable amount of time which cannot be less than five (5) minutes. The NT server has a default timeout value of 15 minutes. Naming On Ipx The name claim/query packet and mailslot datagram packets use the structure: struct ipxnm { uchar inm_route[32]; /* routing info (used by IPX routers) */ uchar inm_op; /* operation being requested */ uchar inm_type; /* type of name */ ushort inm_msgid; /* message ID for sender */ uchar inm_name[16]; /* name being sought or claimed */ uchar inm_srcname[16]; /* name of requesting machine */ }; Below are the values for inm_op: INAME_CLAIM 0xf1 // server name claim message INAME_DELETE 0xf2 // relinquish server name INAME_QUERY 0xf3 // locate server name INAME_FOUND 0xf4 // response to INAME_QUERY IMSG_HANGUP 0xf5 // Messenger Hangup (contained in SMB) IMSLOT_SEND 0xfc // packet contains mslot write, no resp needed IMSLOT_FIND 0xfd // find name for mslot write, no data included IMSLOT_NAME 0xfe // find name response The following are the values for inm_type: INTYPE_MACHINE 1 INTYPE_WKGROUP 2 INTYPE_BROWSER 3 When the server starts, it sends broadcasts a name claim (inm_type == INAME_CLAIM) packet five (5) times at 500 millisecond intervals. The server's name is put into both the inm_name and the inm_srcname fields. The IPX packet type is 32 (0x20) which IPX routers will forward through up to eight (8) hops. If no other machine responds within 500 milliseconds of the transmission of the last broadcast, the server claims the name as its own. When a client wishes to locate the address of a server, it broadcasts a name query (inm_type == INAME_QUERY) packet with the server's name in inm_name and its own name in inm_srcname. The first broadcast is an IPX type 4 packet which is not forwarded by routers. After 500 milliseconds, the client will perform an all nets broadcast (IPX type 32) four (4) times at 500 milliseconds intervals. The client extracts the server's address from the IPX header of the response packet. Once a client has the address of a server, it may open a circuit to the server by sending a negotiate SMB to the SMB_SERVER_SOCKET. In the negotiate request, smb_sid must be zero (0), smb_seq must be one (1) and two 16 bytes names are appended to the end of the SMB in NetBIOS name format. The size of the names is NOT included in the smb_bcc value. The first 16 bytes contains the client computer name space padded with a zero (0) in the 16th position. The second 16 bytes contains the remote server's name space padded to 16 bytes. The server retains the client's name for informational purposes and verifies that the server name matches its own name. If the server name does not match, the server will respond to the negotiate with an ERRSRV class error ERRnotme. The server returns a session identifier in smb_sid which the client must place in smb_sid in all subsequent requests sent to the server. Opportunistic Locks Network performance can be increased if the client can locally buffer file data. For example, the client does not have to write information into a file on the server if the client knows that no other process is accessing the data. Likewise, the client can buffer read-ahead data from the file if the client knows that no other process is writing the data. The mechanism which allows clients to dynamically alter their buffering strategy in a consistent manner is knows as “opportunistic locks”, or oplocks for short. Versions of the SMB file sharing protocol including and newer than the LANMAN1.0 dialect support oplocks. There are three different types of oplocks: 1. An exclusive oplock allows a client to open a file for exclusive access and allows the client to perform arbitrary buffering 2. A batch oplock allows a client to keep a file open on the server even though the local accessor on the client machine has closed the file. 3. A Level II oplock indicates there are multiple readers of a file, and no writers. Level II oplocks are supported if the negotiated dialect is NT LM 0.12 or later. When a client opens a file, it requests the server to grant it a particular type of oplock on the file. The response from the server indicates the type of oplock granted to the client. The client uses the granted oplock type to adjust its buffering policy. The SMB_COM_LOCKING_ANDX SMB is used to convey oplock break and response information. Oplocks are not supported over connectionless transports. Exclusive Oplocks If a client is granted an exclusive oplock, it may buffer lock information, read-ahead data, and write data on the client because the client knows that it is the only accessor to the file. The basic protocol is that the redirector on the client opens the file requesting that an oplock be given to the client. If the file is open by anyone else, then the client is refused the oplock and no local buffering may be performed on the local client. This also means that no readahead may be performed to the file, unless the redirector knows that it has the read ahead range locked. If the server grants the exclusive oplock, the client can perform certain optimizations for the file such as buffering lock, read, and write data. The exclusive oplock protocol is: Client Server A B Open (“foo”) ® Open OK. Exclusive oplock granted. Open(“foo”) ® oplock break to A lock(s) ® lock(s) response(s) write(s) ® write(s) response(s) close or done ® open response to B As can be seen, when client A opens the file, it can request an exclusive oplock. Provided no one else has the file open on the server, then the oplock is granted to client A. If, at some point in the future, another client, such as client B, requests an open to the same file, then the server must have client A break its oplock. Breaking the oplock involves client A sending the server any lock or write data that it has buffered, and then letting the server know that it has acknowledged that the oplock has been broken. This synchronization message informs the server that it is now permissible to allow client B to complete its open. Client A must also purge any readahead buffers that it has for the file. This is not shown in the above diagram since no network traffic is needed to do this. Batch Oplocks Batch oplocks are used where common programs on a client behave in such a way that causes the amount of network traffic on a wire to go beyond an acceptable level for the functionality provided by the program. For example, the command processor executes commands from within a command procedure by performing the following steps: o Opening the command procedure. o Seeking to the "next" line in the file. o Reading the line from the file. o Closing the file. o Executing the command. This process is repeated for each command executed from the command procedure file. As is obvious, this type of programming model causes an inordinate amount of processing of files, thereby creating a lot of network traffic that could otherwise be curtailed if the program were to simply open the file, read a line, execute the command, and then read the next line. Batch oplocking curtails the amount of network traffic by allowing the client to skip the extraneous open and close requests. When the command processor then asks for the next line in the file, the client can either ask for the next line from the server, or it may have already read the data from the file as readahead data. In either case, the amount of network traffic from the client is greatly reduced. If the server receives either a rename or a delete request for the file that has a batch oplock, it must inform the client that the oplock is to be broken. The client can then change to a mode where the file is repeadedly opened and closed. The batch oplock protocol is: Client Server A B Open( “foo” ) ® Open OK. Batch oplock granted. Read ® data ® read data Open(“foo”) ® Oplock break to A Close ® Close ok to A Open OK to B When client A opens the file, it can request an oplock. Provided no one else has the file open on the server, then the oplock is granted to client A. Client A, in this case, keeps the file open for its caller across multiple open/close operations. Data may be read ahead for the caller and other optimizations, such as buffering locks, can also be performed. When another client requests an open, rename, or delete operation to the server for the file, however, client A must cleanup its buffered data and synchronize with the server. Most of the time this involves actually closing the file, provided that client A's caller actually believes that he has closed the file. Once the file is actually closed, client B's open request can be completed. Level II Oplocks Level II oplocks allow multiple clients to have the same file open, providing that no client is performing write operations to the file. This is important for many environments because most compatibility mode opens from down-level clients map to an open request for shared read/write access to the file. While it makes sense to do this, it also tends to break oplocks for other clients even though neither client actually intends to write to the file. The Level II oplock protocol is: Client Server A B Open( “foo” ) ® Open OK. Exclusive oplock granted. Read ® data Open( “foo” ) ® Break to Level II oplock to A lock(s) ® lock(s) response(s) done ® Open OK. Oplock II oplock granted to B This sequence of events is very much like an exclusive oplock. The basic difference is that the server informs the client that it should break to a level II lock when no one has been writing the file. That is, client A, for example, may have opened the file for a desired access of READ, and a share access of READ/WRITE. This means, by definition, that client A will not performed any writes to the file. When client B opens the file, the server must synchronize with client A in case client A has any buffered locks. Once it is synchronized, client B's open request may be completed. Client B, however, is informed that he has a level II oplock, rather than an exclusive oplock to the file. In this case, no client that has the file open with a level II oplock may buffer any lock information on the local client machine. This allows the server to guarantee that if any write operation is performed, it need only notify the level II clients that the lock should be broken without having to synchronize all of the accessors of the file. The level II oplock may be broken to none, meaning that some client that had the file opened has now performed a write operation to the file. Because no level II client may buffer lock information, the server is in a consistent state. The writing client, for example, could not have written to a locked range, by definition. Read ahead data may be buffered in the client machines, however, thereby cutting down on the amount of network traffic required to the file. Once the level II oplock is broken, however, the buffering client must flush its buffers and degrade to performing all operations on the file across the network. No oplock break response is expected from a client when the server breaks a client from level II to none. NAMED PIPES Named pipes provide a facility which allows interprocess communications pipes to be named and act like full duplex virtual circuits between a pair of endpoints. Support of named pipes is server optional, and the earliest valid dialect supporting named pipes is LANMAN1.0. Named Pipe Features Pipes are named and accessed across a network. Once created, named pipes can be opened and read/written like standard files, i.e., using Open, Read, Write, and Close protocols. Named pipes support message as well as byte stream modes. Byte stream mode lets processes read and write byte streams, exactly like byte conventional pipes, except the pipe is full-duplex, emulating a virtual circuit. Message mode lets processes read and write streams of messages (as opposed to bytes). Message mode is optimized for peer-to-peer communication between remote as well as local processes. Named pipes can be serially re-used by different clients (closed and reopened by another process). A serving process can create multiple identically named pipes so that multiple clients opening to that name will get distinct pipes to the serving process. Named pipes are generally used to support some API requests to the server. In early incarnations of Lan Manager networking, use of named pipes for generalized client to server communications was encouraged. Microsoft subsequently provided tools and runtime support for generalized DCE compliant RPC exchanges between clients and servers. The RPC runtime can use named pipes, datagrams, or direct use of transport facilities to communicate between clients and servers, and the RPC MIDL complier allows high level expression of the messages to be exchanged between clients and servers. Developers are strongly encouraged to use the RPC tools to implement client and server protocols rather than coding directly to any named pipe interfaces. SMB Messages And Formats This section describes the entire set of SMB commands and responses exchanged between SMB clients and servers. It also details which SMBs are introduced into the protocol as higher dialect levels are negotiated. SMB Header While each SMB command has specific encodings, there are some fields in the SMB header which have meaning to all SMBs. These fields and considerations are described in the following sections. Flags field This field contains 8 individual flags, numbered from least significant to most significant, and have the following meanings: Bit Meaning Earliest Dialect 0 When set (returned) from the server in the SMB_COM_NEGOTIATE response SMB, this bit indicates that the server supports the "sub dialect" consisting of the Lockan- dRead and WriteandUnlock protocols defined later in this document. LANMAN1.0 1 When on (on an SMB request being sent to the server), the client guarantees that there is a receive buffer posted such that a send without acknowledgement can be used by the server to respond to the client's request. 2 Reserved (must be zero). 3 When on, all pathnames in this SMB must be treated as caseless. When off, the pathnames are case sensitive. LANMAN1.0 4 When on (in SMB_COM_SESSION_SETUP_ANDX defined later in this document), all paths sent to the server by the client are already canonicalized. This means that file/directory names are in upper case, are valid characters, . and .. have been removed, and single backslashes are used as separators. LANMAN1.0 5 When on (in SMB_COM_OPEN, SMB_COM_CREATE and SMB_COM_CREATE_NEW), this indicates that the consumer is requesting that the file be "opportunisticly" locked if this process is the only process which has the file open at the time of the open request. If the server "grants" this oplock request, then this bit should remain set in the coresponding response SMB to indicate to the consumer that the oplock request was granted. See the discussion of "oplock" in the sections defining the SMB_COM_OPEN_ANDX and SMB_COM_LOCKING_ANDX protocols later in this document (this bit has the same function as bit 1 of Flags if the SMB_COM_OPEN_ANDX SMB). LANMAN1.0 6 When on (in core protocols SMB_COM_OPEN_ANDX, SMB_COM_CREATE and SMB_COM_CREATE_NEW), this indicates that the server should notify the client on any action which can modify the file (delete, setattrib, rename, etc.) by another client. If not set, the server need only notify the client about another open request by a different client. See the discussion of "oplock" in the sections defining the SMB_COM_OPEN_ANDX and SMB_COM_LOCKING_ANDX SMBs later in this document (this bit has the same function as bit 2 of smb_flags of the SMB_COM_OPEN_ANDX SMB). Bit6 only has meaning if bit5 is set.. LANMAN1.0 7 When on, this SMB is being sent from the server in response to a client request. The Command field usually contains the same value in a protocol request from the consumer to the server as in the matching response from the server to the consumer. This bit unambiguously distinguishes the command request from the command response. PC NETWORK PROGRAM 1.0 Flags2 Field This field contains six individual flags, numbered from least significant bit to most significant bit, which are defined below. Flags which not defined must be set to zero. Bit Meaning Earilest Dialect 0 If set, the client knows how to handle names which do not conform to the MS-DOS 8.3 naming convention. 1 If set, the consumer is aware of extended attributes 2 If set, SMB_FLAGS2_IS_LONG_NAME 13 If set, indicates that a read will be permitted if the client does not have read permission but does have execute permission. This flag is only useful on a read request. 14 If set, specifies that the returned error code is a 32 bit error code in Status.NtStatus. Otherwise the Status.DosError.ErrorClass and Status.DosError.Error fields contain the DOS-style error information. When passing NT status codes is negotiated, this flag should be set for every SMB. NT LM 0.12 15 If set, any strings in this SMB message are encoded as UNICODE. Otherwise, all strings are in ASCII. NT LM 0.12 Tid Field Tid represents an instance of an authenticated connection to a server resource. Tid is returned by the server to the client when the client successfully connects to a resource, and the client uses Tid in subsequent requests referring to the resource. If the server is executing in a share level security mode, tid is the only thing used to allow access to the shared resource. Thus if the user is able to perform a successful connection to the server specifying the appropriate netname and passwd (if any) the resource may be accessed according to the access rights associated with the shared resource (same for all who gained access this way). If however the server is executing in user level security mode, access to the resource is based on the Uid (validated on the SMB_COM_SESSION_SETUP_ANDX request) and the Tid is NOT associated with access control but rather merely defines the resource (such as the shared directory tree). In most SMB requests, Tid must contain a valid value. Exceptions include prior to getting a Tid established including SMB_COM_NEGOTIATE, SMB_COM_TREE_CONNECT, SMB_COM_ECHO, and SMB_COM_SESSION_SETUP_ANDX. 0xFFFF should be used for Tid for these situations. The server is always responsible for enforcing use of a valid Tid where appropriate. Pid Field Pid uniquely identifies a client process. Clients inform servers of the creation of a new process by simply introducing a new Pid value into the dialogue for new processes. In the core protocol, the SMB_COM_PROCESS_EXIT SMB was used to indicate the catastrophic termination of a process on the client. In the single tasking DOS system, it was possible for hard errors to occur causing the destruction of the process with files remaining open. Thus a SMB_COM_PROCESS_EXIT SMB was sent for this occurrence to allow the server to close all files opened by that process. In the LANMAN 1.0 and newer dialects, no SMB_COM_PROCESS_EXIT SMB is sent. The client operating system must ensure that the appropriate close and cleanup SMBs will be sent when the last process referencing the file closes it. From the server's point of view, there is no concept of FIDs "belonging to" processes. A FID returned by the server to one process may be used by any other process using the same transport connection and Tid. There is no process creation SMB sent to the server; it is up to the client to ensure only valid client processes gain access to Fids (and Tids). On SMB_COM_TREE_DISCONNECT (or when the client and server session is terminated) the server will invalidate any files opened by any process on that client. Mid Field Clients using the LANMAN 1.0 and newer dialects will typically be multitasked and allow multiple asynchronous input/output requests per task. Therefore a multiplex ID (Mid) is used along with Pid to allow multiplexing the single client and server connection among the client’s multiple processes, threads, and requests per thread. Regardless of negotiated dialect, the server is responsible for ensuring that every response contains the same Mid and Pid values as its request. The client may then use the Mid and Pid values for associat- ing requests and responses and may have up to the negotiated number of requests outstanding at any time to a particular server. Status Field An SMB returns error information to the client in the Status field. Protocol dialects prior to NT LM 0.12 return status to the client using the combination of Status.DosError.ErrorClass and Status.DosError.Error. Beginning with NT LM 0.12 SMB servers can return 32 bit error information to clients using Status.NtStatus if the incomming client SMB has bit 14 set in the Flags2 field of the SMB header. Any valid NT status code may be returned in this case. The contents of response parameters is not guaranteed in the case of an error return, and must be ignored. For write behind activity, a subsequent write or close of the file may return the fact that a previous write failed. Normally write behind failures are limited to hard disk errors and device out of space. Timeouts In general, SMBs are not expected to block at the server; they should return “immediately”. But some SMB requests do indicate timeout periods for the completion of the request on the server. If a server implementation can not support timeouts, then an error can be returned just as if a timeout had occurred if the resource is not available immediately upon request. Data Buffer (Buffer) and String Formats The data portion of SMBs typically contains the data to be read or written, file paths, or directory paths. The format of the data portion depends on the message. All fields in the data portion have the same format. In every case it consists of an identifier byte followed by the data. Identifier Description Value Data Block Dialect Pathname ASCII Variable block See Below Null terminated String Null terminated String Null terminated String See Below 1 2 3 4 5 When the identifier indicates a data block or variable block then the format is a word indicating the length followed by the data. In all dialects prior to NT LM 0.12, all strings are encoded in ASCII. If the agreed dialect is NT LM 0.12 or later, Unicode strings may be exchanged. Unicode strings include file names, resource names, and user names. This applies to null-terminated strings, length specified strings and the type- prefixed strings. In all cases where a string is passed in Unicode format, the Unicode string must be word-aligned with respect to the beginning of the SMB. Should the string not naturally fall on a two- byte boundary, a null byte of padding will be inserted, and the Unicode string will begin at the next address. In the description of the SMBs, items that may be encoded in Unicode or ASCII are labelled as STRING. If the encoding is ASCII, even if the negotiatiated string is Unicode, the quantity is labelled as UCHAR. For type-prefixed Unicode strings, the padding byte is found after the type byte. The type byte is 4 (indicating SMB_FORMAT_ASCII) independent of whether the string is Ascii or Unicode. For strings whose start addresses are found using offsets within the fixed part of the SMB (as opposed to simply being found at the byte following the preceding field,) it is guaranteed that the offset will be properly aligned. Strings that are never passed in Unicode are: The protocol strings in the Negotiate SMB request. The service name string in the Tree Connect And X SMB. When Unicode is negotiated, bit 15 should be set in the Flags2 field of every SMB header. Despite the flexible encoding scheme, no field of a data portion may be omitted or included out of order. In addition, neither an WordCount nor ByteCount of value 0 at the end of a message may be omitted. Time And Date Encoding When SMB requests or responses encode time values, the following describes the encoding into 16 bits. struct { USHORT Day : 5; USHORT Month : 4; USHORT Year : 7; } SMB_DATE; The Year field has a range of 0-119, which represents years 1980 - 2099. The Month is encoded as 1- 12, and the day ranges from 1-31. struct { USHORT TwoSeconds : 5; USHORT Minutes : 6; USHORT Hours : 5; } SMB_TIME; Hours ranges from 0-23, Minutes range from 0-59, and TwoSeconds ranges from 0-29 representing two second increments within the minute. typedef struct { ULONG LowTime; LONG HighTime; } TIME; TIME indicates a signed 64-bit integer representing either an absolute time or a time interval. Times are specified in units of 100ns. A positive value expresses an absolute time, where the base time (the 64-bit integer with value 0) is the beginning of the year 1601 AD in the Gregorian calendar. A negative value expresses a time interval relative to some base time, usually the current time. Access Mode Encoding Various client requests and server responses, such as SMB_COM_OPEN, pass file access modes encoded into a USHORT. The encoding of these is as follows: 1111 11 5432 1098 7654 3210 rWrC rLLL rSSS rAAA where: W - Write through mode. No read ahead or write behind allowed on this file or device. When the response is returned, data is expected to be on the disk or device. S - Sharing mode: 0 - Compatibility mode 1 - Deny read/write/execute (exclusive) 2 - Deny write 3 - Deny read/execute 4 - Deny none A - Access mode 0 - Open for reading 1 - Open for writing 2 - Open for reading and writing 3 - Open for execute rSSSrAAA = 11111111 (hex FF) indicates FCB open C - Cache mode 0 - Normal file 1 - Do not cache this file L - Locality of reference 0 - Locality of reference is unknown 1 - Mainly sequential access 2 - Mainly random access 3 - Random access with some locality 4 to 7 - Currently undefined File Attribute Encoding When SMB messages exchange file attribute information, it is encoded in 16 bits as: Value Description 0x01 Read only file 0x02 Hidden file 0x04 System file 0x08 Volume 0x10 Directory 0x20 Archive file others Reserved - must be 0 “ANDX” SMB Messages LANMAN1.0 and later dialects of the SMB protocol allow multiple SMB requests to be sent in one message to the server. Messages of this type are called AndX SMBs, and they obey the following rules: 1. The embedded command does not repeat the SMB header information. Rather the next SMB starts at the WordCount field. 2. All multiple (chained) requests must fit within the negotiated transmit size. For example, if SMB_COM_TREE_CONNECT_ANDX included OPENandX SMB_COM_OPEN_ANDX which included SMB_COM_WRITE were sent, they would all have to fit within the negotiated buffer size. This would limit the size of the write. 3. There is one message sent containing the chained requests and there is one response message to the chained requests. The server may NOT elect to send separate responses to each of the chained requests. 4. All chained responses must fit within the negotiated transmit size. This limits the maximum value on an embedded SMB_COM_READ for example. It is the client's responsibility to not request more bytes than will fit within the multiple response. 5. The server will implicitly use the result of the first command in the "X" command. For example the Tid obtained via SMB_COM_TREE_CONNECT_ANDX would be used in the embedded SMB_COM_OPEN_ANDX and the Fid obtained in the SMB_COM_OPEN_ANDX would be used in the embedded SMB_COM_READ. 6. Each chained request can only reference the same Fid and Tid as the other commands in the combined request. The chained requests can be thought of as performing a single (multi-part) opera- tion on the same resource. 7. The first Command to encounter an error will stop all further processing of embedded commands. The server will not back out commands that succeeded. Thus if a chained request contained SMB_COM_OPEN_ANDX and SMB_COM_READ and the server was able to open the file successfully but the read encountered an error, the file would remain open. This is exactly the same as if the requests had been sent separately. 8. If an error occurs while processing chained requests, the last response (of the chained responses in the buffer) will be the one which encountered the error. Other unprocessed chained requests will have been ignored when the server encountered the error and will not be represented in the chained response. Actually the last valid AndXCommand (if any) will represent the SMB on which the error occurred. If no valid AndXCommand is present, then the error occurred on the first request/response and Command contains the command which failed. In all cases the error information are returned in the SMB header at the start of the response buffer. 9. Each chained request and response contains the offset (from the start of the SMB header) to the next chained request/response (in the AndXOffset field in the various "and X" protocols defined later e.g. SMB_COM_OPEN_ANDX). This allows building the requests unpacked. There may be space between the end of the previous request (as defined by WordCount and ByteCount) and the start of the next chained request. This simplifies the building of chained protocol requests. Note that because the consumer must know the size of the data being returned in order to post the correct number of receives (e.g. SMB_COM_TRANSACTION, SMB_COM_READ_MPX), the data in each response SMB is expected to be truncated to the maximum number of 512 byte blocks (sectors) which will fit (starting at a DWORD boundary) in the negotiated buffer size with the odd bytes remaining (if any) in the final buffer. SMB MESSAGES Valid SMB Messages by Negotiated Dialect The following SMB messages may be exchanged by SMB clients and servers if the PC NETWORK PROGRAM 1.0 dialect is negotiated: SMB_COM_CREATE_DIRECTORY SMB_COM_DELETE_DIRECTORY SMB_COM_OPEN SMB_COM_CREATE SMB_COM_CLOSE SMB_COM_FLUSH SMB_COM_DELETE SMB_COM_RENAME SMB_COM_QUERY_INFORMATION SMB_COM_SET_INFORMATION SMB_COM_READ SMB_COM_WRITE SMB_COM_LOCK_BYTE_RANGE SMB_COM_UNLOCK_BYTE_RANGE SMB_COM_CREATE_TEMPORARY SMB_COM_CREATE_NEW SMB_COM_CHECK_DIRECTORY SMB_COM_PROCESS_EXIT SMB_COM_SEEK SMB_COM_TREE_CONNECT SMB_COM_TREE_DISCONNECT SMB_COM_NEGOTIATE SMB_COM_QUERY_INFORMATION_DISK SMB_COM_SEARCH SMB_COM_OPEN_PRINT_FILE SMB_COM_WRITE_PRINT_FILE SMB_COM_CLOSE_PRINT_FILE SMB_COM_GET_PRINT_QUEUE If the LANMAN 1.0 dialect is negotiated, all of the messages in the previous list must be supported. Clients negotiating LANMAN 1.0 and higher dialects will probably no longer send SMB_COM_PROCESS_EXIT, and the response format for SMB_COM_NEGOTIATE is modified as well. New messages introduced with the LANMAN 1.0 dialect are: SMB_COM_LOCK_AND_READ SMB_COM_WRITE_AND_UNLOCK SMB_COM_READ_RAW SMB_COM_READ_MPX SMB_COM_WRITE_MPX SMB_COM_WRITE_RAW SMB_COM_WRITE_COMPLETE SMB_COM_WRITE_MPX_SECONDARY SMB_COM_SET_INFORMATION2 SMB_COM_QUERY_INFORMATION2 SMB_COM_LOCKING_ANDX SMB_COM_TRANSACTION SMB_COM_TRANSACTION_SECONDARY SMB_COM_IOCTL SMB_COM_IOCTL_SECONDARY SMB_COM_COPY SMB_COM_MOVE SMB_COM_ECHO SMB_COM_WRITE_AND_CLOSE SMB_COM_OPEN_ANDX SMB_COM_READ_ANDX SMB_COM_WRITE_ANDX SMB_COM_SESSION_SETUP_ANDX SMB_COM_TREE_CONNECT_ANDX SMB_COM_FIND SMB_COM_FIND_UNIQUE SMB_COM_FIND_CLOSE The LM1.2X002 dialect introduces these new SMBs: SMB_COM_TRANSACTION2 SMB_COM_TRANSACTION2_SECONDARY SMB_COM_FIND_CLOSE2 SMB_COM_LOGOFF_ANDX NT LM 0.12 dialect introduces: SMB_COM_NT_TRANSACT SMB_COM_NT_TRANSACT_SECONDARY SMB_COM_NT_CREATE_ANDX SMB_COM_NT_CANCEL NEGOTIATE: Negotiate Protocol Client Request Description UCHAR WordCount; // Count of parameter words = 0 USHORT ByteCount; // Count of data bytes; min = 2 struct { UCHAR BufferFormat; // 0x02 -- Dialect UCHAR DialectName[]; // ASCII null-terminated string } Dialects[]; The Client sends a list of dialects that it can communicate with. The response is a selection of one of those dialects (numbered 0 through n) or -1 (hex FFFF) indicating that none of the dialects were acceptable. The negotiate message is binding on the virtual circuit and must be sent. One and only one negotiate message may be sent, subsequent negotiate requests will be rejected with an error response and no action will be taken. The protocol does not impose any particular structure to the dialect strings. Implementors of particular protocols may choose to include, for example, version numbers in the string. If the server does not understand any of the dialect strings, or if PC NETWORK PROGRAM 1.0 is the chosen dialect, the response format is Server Response Description UCHAR WordCount; Count of parameter words = 1 USHORT DialectIndex; Index of selected dialect USHORT ByteCount; Count of data bytes = 0 If the chosen dialect is greater than core up to and including LANMAN2.1, the protocol response format is Server Response Description UCHAR WordCount; Count of parameter words = 13 USHORT DialectIndex; Index of selected dialect USHORT SecurityMode; Security mode: bit 0: 0 = share, 1 = user bit 1: 1 = encrypt passwords USHORT MaxBufferSize; Max transmit buffer size (>= 1024) USHORT MaxMpxCount; Max pending multiplexed requests USHORT MaxNumberVcs; Max VCs between client and server USHORT RawMode; Raw modes supported: bit 0: 1 = Read Raw supported bit 1: 1 = Write Raw supported ULONG SessionKey; Unique token identifying this session SMB_TIME ServerTime; Current time at server SMB_DATE ServerDate; Current date at server USHORT ServerTimeZone; Current time zone at server USHORT EncryptionKeyLength; MBZ if this is not LM2.1 USHORT Reserved; MBZ USHORT ByteCount Count of data bytes UCHAR EncryptionKey[]; The challenge encryption key STRING PrimaryDomain[]; The server's primary domain MaxBufferSize is the size of the largest message which the client can legitimately send to the server If bit0 of the Flags field is set in the negotiate response, this indicates the server supports the SMB_COM_LOCK_AND_READ and SMB_COM_WRITE_AND_UNLOCK client requests. If the SecurityMode field indicates the server is running in user mode, the client must send appropriate SMB_COM_SESSION_SETUP_ANDX requests before the server will allow the client to access resources. If the SecurityMode fields indicates the client should encrypt passwords, the client should use the EncryptionKey to encrypt transmitted passwords. Current servers specify an EncryptionKeyLength of 8. Clients should submit no more than MaxMpxCount distinct unanswered SMBs to the server. MICROSOFT NETWORKS 1.03 clients use a different form of raw reads than documented here, and servers are better off setting RawMode in this response to 0 for such sessions. If the negotiated dialect is DOS LANAMN2.1 or LANMAN2.1, then PrimaryDomain string should be included in this response. If the negotiated dialect is NT LM 0.12, the response format is Server Response Description UCHAR WordCount; Count of parameter words = 17 USHORT DialectIndex; Index of selected dialect UCHAR SecurityMode; Security mode: bit 0: 0 = share, 1 = user bit 1: 1 = encrypt passwords USHORT MaxMpxCount; Max pending multiplexed requests USHORT MaxNumberVcs; Max VCs between client and server ULONG MaxBufferSize; Max transmit buffer size ULONG MaxRawSize; Maximum raw buffer size ULONG SessionKey; Unique token identifying this session ULONG Capabilities; Server capabilities ULONG SystemTimeLow; System (UTC) time of the server (low). ULONG SystemTimeHigh; System (UTC) time of the server (high). USHORT ServerTimeZone; Time zone of server (min from UTC) UCHAR EncryptionKeyLength; Length of encryption key. USHORT ByteCount; Count of data bytes UCHAR EncryptionKey[]; The challenge encryption key UCHAR OemDomainName[]; The name of the domain (in OEM chars) In addition to the definitions above, MaxBufferSize is the size of the largest message which the client can legitimately send to the server. If the client is using a connectionless protocol, MaxBufferSize must be set to the smaller of the server’s internal buffer size and the amount of data which can be placed in a response packet. MaxRawSize specifies the maximum message size the server can send or receive for SMB_COM_WRITE_RAW or SMB_COM_READ_RAW Connectionless clients must set Sid to 0 in the SMB request header. Capabilities allows the server to tell the client what it supports. The bit definitions are: Capability Name Encoding Meaning CAP_RAW_MODE 0x0001 The server supports SMB_COM_READ_RAW and SMB_COM_WRITE_RAW CAP_MPX_MODE 0x0002 The server supports SMB_COM_READ_MPX and SMB_COM_WRITE_MPX CAP_UNICODE 0x0004 The server supports Unicode strings CAP_LARGE_FILES 0x0008 The server supports large files with 64 bit offsets CAP_NT_SMBS 0x0010 The server supports the SMBs particular to the NT LM 0.12 dialect CAP_RPC_REMOTE_APIS 0x0020 The sever supports remote API requests via RPC CAP_NT_STATUS 0x0040 The server can respond with 32 bit status codes in Status.NtStatus CAP_LEVEL_II_OPLOCKS 0x0080 The server supports level 2 oplocks CAP_LOCK_AND_READ 0x0100 The server supports the SMB_COM_LOCK_AND_READ SMB CAP_NT_FIND 0x0200 SESSION_SETUP_ANDX: Session Setup And X This SMB is used to further "Set up" the session normally just established via the negotiate protocol. One primary function is to perform a "user logon" in the case where the server is in user level security mode. The Uid in the SMB header is set by the client to be the userid desired for the AccountName and validated by the AccountPassword. If the negotiated protocol is prior to NT LM 0.12, the format of SMB_COM_SESSION_SETUP_ANDX is: Client Request Description UCHAR WordCount; Count of parameter words = 10 UCHAR AndXCommand; Secondary (X) command; 0xFF = none UCHAR AndXReserved; Reserved (must be 0) USHORT AndXOffset; Offset to next command WordCount USHORT MaxBufferSize; Consumer's maximum buffer size USHORT MaxMpxCount; Actual maximum multiplexed pending requests USHORT VcNumber; 0 = first (only), nonzero=additional VC number ULONG SessionKey; Session key (valid iff VcNumber != 0) USHORT PasswordLength; Account password size ULONG Reserved; Must be 0 USHORT ByteCount; Count of data bytes; min = 0 UCHAR AccountPassword[]; Account Password STRING AccountName[]; Account Name STRING PrimaryDomain[]; Client's primary domain STRING NativeOS[]; Client's native operating system STRING NativeLanMan[]; Client's native LAN Manager type and the response is: Server Response Description UCHAR WordCount; Count of parameter words = 3 UCHAR AndXCommand; Secondary (X) command; 0xFF = none UCHAR AndXReserved; Reserved (must be 0) USHORT AndXOffset; Offset to next command WordCount USHORT Action; Request mode: bit0 = logged in as GUEST USHORT ByteCount; Count of data bytes STRING NativeOS[]; Server's native operating system STRING NativeLanMan[]; Server's native LAN Manager type STRING PrimaryDomain[]; Server's primary domain Because AccountPassword may be encrypted, it is a variable length field with the length specified by PasswordLength (if password encryption is not being used, AccountPassword should be a null terminated ASCII string with PasswordLength set to the string size including the null). The password is case insensitive. The server validates the name and password supplied and if valid, it registers the user identifier on this session as representing the specified AccountName. The Uid field in the SMB header will then be used to validate access on subsequent SMB requests. The SMB requests where permission checks are required are those which refer to a symbolically named resource such as SMB_COM_OPEN, SMB_COM_RENAME, SMB_COM_DELETE, etc.. The value of the Uid is relative to a specific client/server session so it is possible to have the same Uid value represent two different users on two different sessions at the server. Multiple session setup commands may be sent to register additional users on this session. If the server receives an additional SMB_COM_SESSION_SETUP_ANDX, only theUid, AccountName and AccountPassword fields need contain valid values (the server will ignore the other fields). The client writes the name of its domain in PrimaryDomain if it knows what the domain name is. If the domain name is unknown, the client either encodes it as a NULL string, or as a question mark. If the server is in "share level security mode", the account name and passwd should be ignored by the server. If bit0 of Action is set, this informs the client that although the server did not recognize the AccountName, it logged the user in as a guest. This is optional behavior by the server, and in any case one would ordinarily expect guest privileges to limited. Another function of the Session Set Up protocol is to inform the server of the maximum values which will be utilized by this consumer. Here MaxBufferSize is the maximum message size which the con- sumer can receive. Thus although the server may support 16k buffers (as returned in the SMB_COM_NEGOTIATE response), if the consumer only has 4k buffers, the value of MaxBufferSize here would be 4096. The minimum allowable value for MaxBufferSize is 1024. The SMB_COM_NEGOTIATE response includes the server buffer size supported. Thus this is the max SMB message size which the consumer can send to the server. This size may be larger than the size returned to the server from the client via the SMB_COM_SESSION_SETUP_AND X protocol which is the maximum SMB message size which the server may send to the consumer. Thus if the server's buffer sizewere 4k and the consumer's buffer size were only 2K, the consumer could send up to 4k (standard) write requests but must only request up to 2k for (standard) read requests. The field, MaxMpxCount informs the server of the maximum number of requests which the client will have outstanding to the server simultaneously. The VcNumber field specifies whether the consumer wants this to be the first VC or an additional VC. The values for MaxBufferSize, MaxMpxCount, and VcNumber must be less than or equal to the maximum values supported by the server as returned in the SMB_COM_NEGOTIATE response. If the server gets a SMB_COM_SESSION_SETUP_ANDX request with VcNumber of 0 and other VCs are still connected to that client, they will be aborted thus freeing any resources held by the server. This condition could occur if the client was rebooted and reconnected to the server before the transport level had informed the server of the previous VC termination. If the negotiated SMB dialect is NT LM 0.12 or later, the format of the response SMB is unchanged, but the request is: Client Request Description UCHAR WordCount; Count of parameter words = 13 UCHAR AndXCommand; Secondary (X) command; 0xFF = none UCHAR AndXReserved; Reserved (must be 0) USHORT AndXOffset; Offset to next command WordCount USHORT MaxBufferSize; Consumer's maximum buffer size USHORT MaxMpxCount; Actual maximum multiplexed pending requests USHORT VcNumber; 0 = first (only), nonzero=additional VC number ULONG SessionKey; Session key (valid iff VcNumber != 0) USHORT CaseInsensitivePasswordLength; Account password size, ANSI USHORT CaseSensitivePasswordLength; Account password size, Unicode ULONG Reserved; must be 0 ULONG Capabilities; Client capabilities USHORT ByteCount; Count of data bytes; min = 0 UCHAR CaseInsensitivePassword[]; Account Password, ANSI UCHAR CaseSensitivePassword[]; Account Password, Unicode STRING AccountName[]; Account Name, Unicode STRING PrimaryDomain[]; Client's primary domain, Unicode STRING NativeOS[]; Client's native operating system, Unicode STRING NativeLanMan[]; Client's native LAN Manager type, Unicode The client expresses its capabilities to the server encoded in the Capabilities field: Capability Name Encoding Description CAP_UNICODE 0x0004 The client can use UNICODE strings CAP_LARGE_FILES 0x0008 The client can deal with files having 64 bit offsets CAP_NT_SMBS 0x0010 The client understands the SMBs introduced with the NT LM 0.12 dialect. Implies CAP_NT_FIND. CAP_NT_FIND 0x0200 CAP_NT_STATUS 0x0040 The client can receive 32 bit errors encoded in Status.NtStatus CAP_LEVEL_II_OPLOCKS 0x0080 The client understands Level II oplocks The entire message sent and received including the optional ANDX SMB must fit in the negotiated max transfer size. The following are the only valid SMB commands for AndXCommand for SMB_COM_SESSION_SETUP_ANDX SMB_COM_TREE_CONNECT_ANDX SMB_COM_OPEN SMB_COM_OPEN_ANDX SMB_COM_CREATE SMB_COM_CREATE_NEW SMB_COM_CREATE_DIRECTORY SMB_COM_DELETE SMB_COM_DELETE_DIRECTORY SMB_COM_FIND SMB_COM_FIND_UNIQUE SMB_COM_COPY SMB_COM_RENAME SMB_COM_NT_RENAME SMB_COM_CHECK_DIRECTORY SMB_COM_QUERY_INFORMATION SMB_COM_SET_INFORMATION SMB_COM_OPEN_PRINT_FILE SMB_COM_GET_PRINT_QUEUE SMB_COM_TRANSACTION SMB_COM_NO_ANDX_COMMAND LOGOFF_ANDX: User Logoff And X This SMB is the inverse of SMB_COM_SESSION_SETUP_ANDX. Client Request Description UCHAR WordCount; Count of parameter words = 2 UCHAR AndXCommand; Secondary (X) command; 0xFF = none UCHAR AndXReserved; Reserved (must be 0) USHORT AndXOffset; Offset to next command WordCount USHORT ByteCount; Count of data bytes = 0 Server Response Description UCHAR WordCount; Count of parameter words = 2 UCHAR AndXCommand; Secondary (X) command; 0xFF = none UCHAR AndXReserved; Reserved (must be 0) USHORT AndXOffset; Offset to next command WordCount USHORT ByteCount; Count of data bytes = 0 The user represented by Uid in the SMB header is logged off. The server closes all files currently open by this user, and invalidates any outstanding requests with this Uid. SMB_COM_SESSION_SETUP_ANDX is the only valid AndXCommand. for this SMB. TREE_CONNECT: Tree Connect When a client connects to a server resource, an SMB_COM_TREE_CONNECT message is generated to the server. Client Request Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes; min = 4 UCHAR BufferFormat1; 0x04 STRING Path[]; Server name and share name UCHAR BufferFormat2; 0x04 STRING Password[]; Password UCHAR BufferFormat3; 0x04 STRING Service[]; Service name The serving machine verifies the combination and returns an error code or an identifier. The full name is included in this request message and the identifier identifying the connection is returned in the Tid field of the SMB header. The Tid field in the client request is ignored. The meaning of this identifier (Tid) is server specific; the client must not associate any specific meaning to it. If the negotiated dialect is prior to LANMAN1.0 and the client has not sent a succesful SMB_COM_SESSION_SETUP_ANDX request when the tree connect arrives, a user level server must nevertheless validate the client’s credentials as discussed earlier in this document. If the negotiated dialect is LANMAN1.0 and later, then it is a protocol violation for the client to send this message prior to a successful SMB_COM_SESSION_SETUP_ANDX. Having received an SMB_COM_SESSION_SETUP_AND_X, the server ignores Password. Path follows UNC style syntax, that is to say it is encoded as \\server\share and it indicates the name of the resource the client wishes to connect to. If the server is paused, administrative privilege is required to connect to any share; if the server is not paused, admin privilege is required only for administrative shares (C$, etc.). Of course, the server can enforce whatever policy it desires to govern share access. Such policies may include valid times of day, software usage license limits, number of simultaneous server users or share users, etc. The Service component indicates the type of resource the client intends to access. Valid values are: Service Description Earliest Dialect Allowed A: disk share PC NETWORK PROGRAM 1.0 LPT1: printer PC NETWORK PROGRAM 1.0 IPC named pipe MICROSOFT NETWORKS 3.0 COMM communications device MICROSOFT NETWORKS 3.0 ????? any type of device MICROSOFT NETWORKS 3.0 The SMB server responds with: Server Response Description UCHAR WordCount; Count of parameter words = 2 USHORT MaxBufferSize; Max size message the server handles USHORT Tid; Tree ID USHORT ByteCount; Count of data bytes = 0 If the negotiated dialect is MICROSOFT NETWORKS 1.03 or earlier, MaxBufferSize in the response message indicates the maximum size message that the server can handle. The client should not generate messages, nor expect to receive responses, larger than this. This must be constant for a given server. For newer dialects, this field is ignored. Tid should be included in any future SMBs referencing this tree connection. TREE_CONNECT_ANDX: Tree Connect And X Client Request Description UCHAR WordCount; Count of parameter words = 4 UCHAR AndXCommand; Secondary (X) command; 0xFF = none UCHAR AndXReserved; Reserved (must be 0) USHORT AndXOffset; Offset to next command WordCount USHORT Flags; Additional information bit 0 set = disconnect Tid USHORT PasswordLength; Length of Password[] USHORT ByteCount; Count of data bytes; min = 3 UCHAR Password[]; Password STRING Path[]; Server name and share name STRING Service[]; Service name This message generally functions just as SMB_COM_TREE_CONNECT, except it allows an AndXCommand to follow. Because Password may be encrypted, it is a variable length field with the length specified by PasswordLength. If password encryption is not being used, Password should be a null terminated ASCII string with PasswordLength set to the string size including the terminating null. Service is as described for SMB_COM_TREE_CONNECT. If bit0 of Flags is set, the tree connection to Tid in the SMB header should be disconnected. If this tree disconnect fails, the error should be ignored. If the negotiated dialect is earlier than DOS LANMAN2.1, the response to this SMB is: Server Response Description UCHAR WordCount; Count of parameter words = 2 UCHAR AndXCommand; Secondary (X) command; 0xFF = none UCHAR AndXReserved; Reserved (must be 0) USHORT AndXOffset; Offset to next command WordCount USHORT ByteCount; Count of data bytes; min = 3 If the negotiated is DOS LANMAN2.1 or later, the response to this SMB is: Server Response Description UCHAR WordCount; Count of parameter words = 3 UCHAR AndXCommand; Secondary (X) command; 0xFF = none UCHAR AndXReserved; Reserved (must be 0) USHORT AndXOffset; Offset to next command WordCount USHORT OptionalSupport; Optional support bits USHORT ByteCount; Count of data bytes; min = 3 UCHAR Service[]; Service type connected to. Always ANSII STRING NativeFileSystem[]; Native file system for this tree NativeFileSystem is the name of the filesystem; values to be expected include FAT, NTFS, etc. OptionalSupport bits has the encoding: Name Encoding Description SMB_SUPPORT_SEARCH_BITS 0x0001 Valid AndX following commands are SMB_COM_OPEN SMB_COM_OPEN_ANDX SMB_COM_CREATE SMB_COM_CREATE_NEW SMB_COM_CREATE_DIRECTORY SMB_COM_DELETE SMB_COM_DELETE_DIRECTORY SMB_COM_FIND SMB_COM_FIND_UNIQUE SMB_COM_COPY SMB_COM_RENAME SMB_COM_NT_RENAME SMB_COM_CHECK_DIRECTORY SMB_COM_QUERY_INFORMATION SMB_COM_SET_INFORMATION SMB_COM_OPEN_PRINT_FILE SMB_COM_GET_PRINT_QUEUE SMB_COM_TRANSACTION SMB_COM_NO_ANDX_COMMAND TREE_DISCONNECT: Tree Disconnect This message informs the server that the client no longer wishes to access the resource connected to with a prior SMB_COM_TREE_CONNECT or SMB_COM_TREE_CONNECT_ANDX. Client Request Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 The resource sharing connection identified by Tid in the SMB header is logically disconnected from the server. Tid is invalidated; it will not be recognized if used by the client for subsequent requests. All locks, open files, etc. created on behalf of Tid are released. Server Response Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 CREATE_DIRECTORY: Create Directory The create directory message is sent to create a new directory. The appropriate Tid and additional pathname are passed. The directory must not exist for it to be created. Client Request Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes; min = 2 UCHAR BufferFormat; 0x04 STRING DirectoryName[]; Directory name Servers require clients to have at least create permission for the subtree containing the directory in order to create a new directory. The creator's access rights to the new directory are be determined by local policy on the server. Server Response Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 DELETE_DIRECTORY: Delete Directory The delete directory message is sent to delete an empty directory. The appropriate Tid and additional pathname are passed. The directory must be empty for it to be deleted. Client Request Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes; min = 2 UCHAR BufferFormat; 0x04 STRING DirectoryName[]; Directory name The directory to be deleted cannot be the root of the share specified by Tid. Server Response Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 CHECK_DIRECTORY: Check Directory This SMB is used to verify that a path exists and is a directory. No error is returned if the given path exists and the client has read access to it. Client machines which maintain a concept of a "working directory" will find this useful to verify the validity of a "change working directory" command. Note that the servers do NOT have a concept of working directory for a particular client. The client must always supply full pathnames relative to the Tid in the SMB header. Client Request Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes; min = 2 UCHAR BufferFormat; 0x04 STRING DirectoryPath[]; Directory path Server Response Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 DOS clients, in particular, depend on the SMB_ERR_BAD_PATH return code if the directory is not found. OPEN: Open File This message is sent to obtain a file handle for a data file. This returned Fid is used in subsequent client requests such as read, write, close, etc. Client Request Description UCHAR WordCount; Count of parameter words = 2 USHORT DesiredAccess; Mode - read/write/share USHORT SearchAttributes; USHORT ByteCount; Count of data bytes; min = 2 UCHAR BufferFormat; 0x04 STRING FileName[]; File name FileName is the fully qualified file name, relative to the root of the share specified in the Tid field of the SMB header. If Tid in the SMB header referrs to a print share, this SMB creates a new file which will be spooled to the printer when closed. In this case, FileName is ignored. SearchAttributes specifies the type of file desired. The encoding is described in the File Attribute Encoding section. DesiredAccess controls the mode under which the file is opened, and the file will be opened only if the client has the appropriate permissions. The encoding of DesiredAccess is discussed in the section entitled Access Mode Encoding. Server Response Description UCHAR WordCount; Count of parameter words = 7 USHORT Fid; File handle USHORT FileAttributes; Attributes of opened file SMB_DATE LastWriteTime; Time file was last written SMB_TIME LastWriteDate; Date file was last written ULONG DataSize; File size USHORT GrantedAccess; Access allowed USHORT ByteCount; Count of data bytes = 0 Fid is the handle value which should be used for subsequent file operations. FileAttributes specifies the type of file obtained. The encoding is described in the File Attribute Encoding section. GrantedAccess indicates the access permissions actually allowed, and may have one of the following values: 0 read-only 1 write-only 2 read/write File Handles (Fids) are scoped per client. A Pid may reference any Fid established by itself or any other Pid on the client (so far as the server is concerned). The actual accesses allowed through the Fid depends on the open and deny modes specified when the file was opened (see below). The MS-DOS compatibility mode of file open provides exclusion at the client level. A file open in compatibility mode may be opened (also in compatibility mode) any number of times for any combination of reading and writing (subject to the user's permissions) by any Pid on the same client. If the first client has the file open for writing, then the file may not be opened in any way by any other client. If the first client has the file open only for reading, then other clientss may open the file, in compatibility mode, for reading.. The above notwithstanding, if the filename has an extension of .EXE, .DLL, .SYM, or .COM other clients are permitted to open the file regardless of read/write open modes of other compatibility mode opens. However, once multiple clients have the file open for reading, no client is permitted to open the file for writing and no other client may open the file in any mode other than compatibility mode The other file exclusion modes (Deny read/write, Deny write, Deny read, Deny none) provide exclusion at the file level. A file opened in any "Deny" mode may be opened again only for the accesses allowed by the Deny mode (subject to the user's permissions). This is true regardless of the identity of the second opener -a different client, a Pid from the same client, or the Pid that already has the file open. For example, if a file is open in "Deny write" mode a second open may only obtain read permission to the file. Although Fids are available to all Pids on a client, Pids other than the owner may not have the full access rights specified in the open mode by the Fid's creator. If the open creating the Fid specified a deny mode, then any Pid using the Fid, other than the creating Pid, will have only those access rights determined by "anding" the open mode rights and the deny mode rights, i.e., the deny mode is checked on all file accesses. For example, if a file is opened for Read/Write in Deny write mode, then other clients may only read the file and cannot write; if a file is opened for Read in Deny read mode, then the other clients can neither read nor write the file. CREATE: Create File This message is sent to create a new data file or truncate an existing data file to length zero, and open the file. The handle returned can be used in subsequent read, write, lock, unlock and close messages. Client Request Description UCHAR WordCount; Count of parameter words = 3 USHORT FileAttributes; New file attributes SMB_TIME CreationTime; Time file was created SMB_DATE CreationDate; Date file was created USHORT ByteCount; Count of data bytes; min = 2 UCHAR BufferFormat; 0x04 STRING FileName[]; File name FileName is the fully qualified name of the file relative to Tid. FileAttributes are encoded as described in the File Attribute Encoding section. Server support of the CreationTime and CreationDate fields is optional. Encoding of these fields is discussed in the Time And Date Encoding section. Server Response Description UCHAR WordCount; Count of parameter words = 1 USHORT Fid; File handle USHORT ByteCount; Count of data bytes = 0 Clients must have write permission on the file's parent directory in order to create a new file, or write permission on the file itself in order to truncate it. The access permissions granted on a created file will be read/write permission for the creator. Access permissions for truncated files are not modified. The newly created or truncated file is opened in read/write/compatibility mode. CLOSE: Close File The close message is sent to invalidate a file handle for the requesting process. All locks or other resources held by the requesting process on the file should be released by the server. The requesting process can no longer use Fid for further file access requests. Client Request Description UCHAR WordCount; Count of parameter words = 3 USHORT Fid; File handle SMB_TIME LastWriteTime Time of last write SMB_DATE LastWriteDate; Date of last write USHORT ByteCount; Count of data bytes = 0 If LastWriteTime and LastWriteDate are 0, the server should allow its local operating system to set the file’s times. Otherwise, the server should set the time to the values requested. Failure to set the times, even if requested by the client in the request message, should not result in an error response from the server. If Fid refers to a print spool file, the file should be spooled to the printer at this time. Server Response Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 FLUSH: Flush File The flush SMB is sent to ensure all data and allocation information for the corresponding file has been written to stable storage. When the Fid has a value -1 (hex FFFF) the server performs a flush for all file handles associated with the client and Pid. The response is not sent until the writes are complete. Client Request Description UCHAR WordCount; Count of parameter words = 1 USHORT Fid; File handle USHORT ByteCount; Count of data bytes = 0 This client request is probably expensive to perform at the server, since the server’s operating system is generally scheduling disk writes is a way which is optimal for the system’s read and write activity integrated over the entire population of clients. This message from a client “interferes” with the server’s ability to optimally schedule the disk activity; clients are discouraged from overuse of this SMB request. Server Response Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 DELETE: Delete File The delete file message is sent to delete a data file. The appropriate Tid and additional pathname are passed. Read only files may not be deleted, the read-only attribute must be reset prior to file deletion. Client Request Description UCHAR WordCount; Count of parameter words = 1 USHORT SearchAttributes; USHORT ByteCount; Count of data bytes; min = 2 UCHAR BufferFormat; 0x04 STRING FileName[]; File name Multiple files may be deleted in response to a single request as SMB_COM_DELETE supports "wild cards" in the last component of FileName. "?" is the wild card for single characters, "*" or "null" matches any number of filename characters within a single part of the filename component. The filename is divided into two parts -an eight character name and a three character extension. The name and extension are divided by a ".". If a filename part commences with one or more "?"s then exactly that number of characters will be matched by the wildcards, e.g., "??x" equals "abx" but not "abcx" or "ax". When a filename part has trailing "?"s then it matches the specified number of characters or less, e.g., "x??" matches "xab", "xa" and "x", but not "xabc". If only "?"s are present in the filename part, then it is handled as for trailing "?"s "*" or "null" match entire pathname parts, thus "*.abc" or ".abc" matches any file with an extension of "abc". "*.*", "*" or "null" matches all files in a directory. SearchAttributes indicates the attributes that the target file(s) must have. If the attribute is zero then only normal files are deleted. If the system file or hidden attributes are specified then the delete is inclusive -both the specified type(s) of files and normal files are deleted. Attributes are described in the Attribute Encoding section of this document. If bit0 of the Flags2 field of the SMB header is set, a pattern is passed in, and the file has a long name, then the passed pattern much match the long file name for the delete to succeed. If bit0 is clear, a pattern is passed in, and the file has a long name, then the passed pattern must match the file’s short name for the deletion to succeed.j Server Response Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 RENAME: Rename File The rename file message is sent to change the name of a file. Client Request Description UCHAR WordCount; Count of parameter words = 1 USHORT SearchAttributes; Target file attributes USHORT ByteCount; Count of data bytes; min = 4 UCHAR BufferFormat1; 0x04 STRING OldFileName[]; Old file name UCHAR BufferFormat2; 0x04 STRING NewFileName[]; New file name Files OldFileName must exist and NewFileName must not. Both pathnames must be relative to the Tid specified in the request. Open files may be renamed. Multiple files may be renamed in response to a single request as Rename File supports "wild cards" in the file name (last component of the pathname). The wild card matching algorithm is described in the SMB_COM_DELETE description. SearchAttributes indicates the attributes that the target file(s) must have. If SearchAttributes is zero then only normal files are renamed. If the system file or hidden attributes are specified then the rename is inclusive -both the specified type(s) of files and normal files are renamed. The encoding of SearchAttributes is described in the Attribute Encoding section of this document. Server Response Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 QUERY_INFORMATION: Get File Attributes This request is sent to obtain information about a file. Client Request Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes; min = 2 UCHAR BufferFormat; 0x04 STRING FileName[]; File name FileName is the fully qualified name of the file relative to the Tid in the header. Server Response Description UCHAR WordCount; Count of parameter words = 10 USHORT FileAttributes; SMB_TIME LastWriteTime; Time of last write SMB_DATE LastWriteDate; Date of last write ULONG FileSize; File size USHORT Reserved [5]; Reserved - client should ignore USHORT ByteCount; Count of data bytes = 0 FileAttributes are as described in the Attributes Encoding section of this document. Note that FileSize is limited to 32 bits, this request is inappropriate for files whose size is too large. SET_INFORMATION: Set File Attributes This message is sent to change the information about a file. Client Request Description UCHAR WordCount; Count of parameter words = 8 USHORT FileAttributes; Attributes of the file SMB_TIME LastWriteTime; Time of last write SMB_DATE LastWriteDate; Date of last write USHORT Reserved [5]; Reserved (must be 0) USHORT ByteCount; Count of data bytes; min = 2 UCHAR BufferFormat; 0x04 STRING FileName[]; File name FileName is the fully qualified name of the file relative to the Tid. Support of all parameters is optional. A server which does not implement one of the parameters will ignore that field. If the LastWriteTime and LastWriteDate fields contain zero then the file's time is not changed. Server Response Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 READ: Read File The read message is sent to read bytes of a resource indicated by Fid in the SMB header. Client Request Description UCHAR WordCount; Count of parameter words = 5 USHORT Fid; File handle USHORT Count; Count of bytes being requested ULONG Offset; Offset in file of first byte to read USHORT Remaining; Estimate of bytes to read if nonzero USHORT ByteCount; Count of data bytes = 0 Count is used to specify the requested number of bytes. Offset specifies the offset in the file of the first byte to be read. Note that this offset is limited to 32 bits, so this client request is inappropriate for files having 64 bit offsets. Remaining is advisory. If the value is not zero, then it is taken as an estimate of the total number of bytes that will be read, including those read by this request. This additional information may be used by the server to optimize buffer allocation or read-ahead. Server Response Description UCHAR WordCount; Count of parameter words = 5 USHORT Count; Count of bytes actually returned USHORT Reserved [4]; Reserved (must be 0) USHORT ByteCount; Count of data bytes UCHAR BufferFormat; 0x01 -- Data block USHORT DataLength; Length of data ByteCount is the number of bytes actually being returned. If Fid referrs to a disk file, ByteCount may be less than the count requested only if a read specifies bytes beyond the current file size. In this case only the bytes that exist are returned. A read completely beyond the end of file results in a response of length zero. This is the only circumstance when a zero length response is generated. A count returned which is less than the count requested is the end of file indicator. If a Read requests more data than can be placed in a message of the max-xmit-size for the Tid specified, the server will abort the connection to the consumer. WRITE: Write Bytes The write message is sent to write bytes into the resource indicated by Fid in the SMB header. Client Request Description UCHAR WordCount; Count of parameter words = 5 USHORT Fid; File handle USHORT Count; Number of bytes to be written ULONG Offset; Offset in file to begin write USHORT Remaining; Bytes remaining to satisfy request USHORT ByteCount; Count of data bytes UCHAR BufferFormat; 0x01 -- Data block USHORT DataLength; Length of data UCHAR Data[ Count ]; The data to write Count specifies the number of bytes to be written. Offset is the offset in the file of the first byte to be written. Since offset is 32 bits, this request is inappropriate for general use in a very large file. Remaining is advisory: if the value is not zero, then it is taken as an estimate of the number of bytes that will be written -including those written by this request. This additional information may be used by the server to optimize cache behavior. When Fid represents a disk file and the request specifies a byte range beyond the current end of file, the file will be extended. Any bytes between the previous end of file and the requested offset are initialized to 0. When a write specifies a length of zero, the file is truncated (or extended) to the length specified by the offset. Server Response Description UCHAR WordCount; Count of parameter words = 1 USHORT Count; Count of bytes actually written USHORT ByteCount; Count of data bytes = 0 Count in the response indicates the actual number of bytes written, and for successful writes will always equal the count in the request message. If the number of bytes written differs from the number requested and no error is indicated, then the server has no resources available with which to satisfy the complete write. If a Write sends a message of length greater than the MaxBufferSize for the TID specified, the server may abort the connection to the client. LOCK_BYTE_RANGE: Lock Bytes The lock record message is sent to lock the given byte range. More than one non-overlapping byte range may be locked in a given file. Locks prevent prevent attempts to lock, read or write the locked portion of the file by other clients or Pids. Overlapping locks are not allowed. Offsets beyond the current end of file may be locked. Such locks will not cause allocation of file space. Since Offset is a 32 bit quantity, this request is inappropriate for general locking within a very large file. Client Request Description UCHAR WordCount; Count of parameter words = 5 USHORT Fid; File handle ULONG Count; Count of bytes to lock ULONG Offset; Offset from start of file USHORT ByteCount; Count of data bytes = 0 Locks may only be unlocked by the Pid that performed the lock. Server Response Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 This client request does not wait for the lock to be granted. If the lock can not be immediately granted (within 200-300 mS), the server should return failure to the client UNLOCK_BYTE_RANGE: Unlock Bytes This message is sent to unlock the given byte range. Offset, Count, and Pid must be identical to that specified in a prior successful lock. If an unlock references an address range that is not locked, no error is generated. Since Offset is a 32 bit quantity, this request is inappropriate for general locking within a very large file. Client Request Description UCHAR WordCount; Count of parameter words = 5 USHORT Fid; File handle ULONG Count; Count of bytes to unlock ULONG Offset; Offset from start of file USHORT ByteCount; Count of data bytes = 0 Server Response Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 CREATE_TEMPORARY: Create Temporary File The server creates a data file in Directory relative to Tid in the SMB header and assigns a unique name to it. Client Request Server Response UCHAR WordCount; Count of parameter words = 3 USHORT reserved; Ignored by the server SMB_TIME CreationTime; New file’s time stamp SMB_DATE CreationDate; New file’s date stamp USHORT ByteCount; Count of data bytes; min = 2 UCHAR BufferFormat; 0x04 STRING DirectoryName[]; Directory name Server Response Description UCHAR WordCount; Count of parameter words = 1 USHORT Fid; File handle USHORT ByteCount; Count of data bytes; min = 2 UCHAR BufferFormat; 0x04 STRING Filename[]; File name Fid is the returned handle for future file access. Filename is the name of the file which was created within the requested Directory. It is opened in compatibility mode with read/write access for the client. Support of CreationTime and CreationDate by the server is optional. CREATE_NEW: Create File This message is sent to create a new data file or truncate an existing data file to length zero, and open the file. Client Request Description UCHAR WordCount; Count of parameter words = 3 USHORT FileAttributes; New file attributes SMB_TIME CreationTime; Time of created file SMB_DATE CreationDate; Date for created file USHORT ByteCount; Count of data bytes; min = 2 UCHAR BufferFormat; 0x04 STRING FileName[]; File name FileAttributes specify the attributes of the newly created file, their encoding is described in the Attribute Encoding section of this document. CreationTime and CreationDate are the timestamp the file should be given, server support for these is optional. Server Response Description UCHAR WordCount; Count of parameter words = 1 USHORT Fid; File handle USHORT ByteCount; Count of data bytes = 0 The returned Fid can be used in subsequent Fid-related messages. The access permissions granted on a created file are read/write permission for the creator. Access permissions for truncated files are not modified. The newly created or truncated file is opened in read/write/compatibility mode. PROCESS_EXIT: Process Exit This command informs the server that a consumer process has terminated. The server must close all files opened by Pid in the SMB header. This must automatically release all locks the process holds. Client Request Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 Server Response Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 This SMB should not generate any errors from the server, unless the server is a user mode server and Uid in the SMB header is invalid. Clients are not required to send this SMB, they can do all cleanup necessary by sending close SMBs to the server to release resources. In fact, clients who have negotiated LANMAN 1.0 and later probably do not send this message at all. SEEK: Seek in File The seek message is sent to set the current file pointer for Fid. Client Request Description UCHAR WordCount; Count of parameter words = 4 USHORT Fid; File handle USHORT Mode; Seek mode: 0 = from start of file 1 = from current position 2 = from end of file LONG Offset; Relative offset USHORT ByteCount; Count of data bytes = 0 The starting point of the seek is set by Mode: 0 seek from start of file 1 seek from current file pointer 2 seek from end of file The “current position” reflects the offset plus data length specified in the previous read, write or seek request, and the pointer set by this command will be replaced by the offset specified in the next read, write or seek command. Server Response Description UCHAR WordCount; Count of parameter words = 2 ULONG Offset; Offset from start of file USHORT ByteCount; Count of data bytes = 0 The response returns the new file pointer in Offset which is expressed as the offset from the start of the file, and may be beyond the current end of file. An attempt to seek to before the start of file sets the current file pointer to start of the file. This request should generally only be issued by clients wishing to find the size of a file, since all read and write requests include the read or write file position as part of the SMB. This request is inappropriate for very large files, as the offsets specified are only 32 bits. A seek which results in an Offset which can not be expressed in 32 bits returns the least significant . SMB_QUERY_INFORMATION_DISK: Get Disk Attributes This command is used to determine the capacity and remaining free space on the drive hosting the directory structure indicated by Tid in the SMB header. Client Request Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 Server Response Description UCHAR WordCount; Count of parameter words = 5 USHORT TotalUnits; Total allocation units per server USHORT BlocksPerUnit; Blocks per allocation unit USHORT BlockSize; Block size (in bytes) USHORT FreeUnits; Number of free units USHORT Reserved; Reserved (client should ignore) USHORT ByteCount; Count of data bytes = 0 The blocking/allocation units used in this response may be independent of the actual physical or logical blocking/allocation algorithm(s) used internally by the server. However, they must accurately reflect the amount of space on the server. This SMB only returns 16 bits of information for each field, which may not be large enough for some disk systems. In particular TotalUnits is commonly > 64K. Fortunately, it turns out the all the client cares about is the total disk size, in bytes, and the free space, in bytes. So, it is reasonable for a server to adjust the relative values of BlocksPerUnit and BlockSize to accomodate. If after all adjustment, the numbers are still too high, the largest possible values for TotalUnit or FreeUnits (i.e. 0xFFFF) should be returned. SEARCH: Search Directory This command is used to search directories. Client Request Description UCHAR WordCount; Count of parameter words = 2 USHORT MaxCount; Number of dir. entries to return USHORT SearchAttributes; USHORT ByteCount; Count of data bytes; min = 5 UCHAR BufferFormat1; 0x04 -- ASCII UCHAR FileName[]; File name, may be null UCHAR BufferFormat2; 0x05 -- Variable block USHORT ResumeKeyLength; Length of resume key, may be 0 UCHAR ResumeKey[]; Resume key FileName specifies the file to be sought. SearchAttributes indicates the attributes that the file must have, and is described in the File Attribute Encoding section of this document. If SearchAttributes is zero then only normal files are returned. If the system file, hidden or directory attributes are specified then the search is inclusive-both the specified type(s) of files and normal files are returned. If the volume label attribute is specified then the search is exclusive, and only the volume label entry is returned. MaxCount specifies the number of directory entries to be returned. Server Response Description UCHAR WordCount; Count of parameter words = 1 USHORT Count; Number of entries returned USHORT ByteCount; Count of data bytes; min = 3 UCHAR BufferFormat; 0x05 -- Variable block USHORT DataLength; Length of data UCHAR DirectoryInformationData[]; Data The response will contain one or more directory entries as determined by the Count field. No more than MaxCount entries will be returned. Only entries that match the sought FileName and SearchAttributes combination will be returned. ResumeKey must be null (length = 0) on the initial search request. Subsequent search requests intended to continue a search must contain the ResumeKey field extracted from the last directory entry of the previous response. ResumeKey is self-contained, for on calls containing a non-zero ResumeKey neither the SearchAttributes or FileName fields will be valid in the request. ResumeKey has the following format: Resume Key Field Description UCHAR Reserved; bit 7 - comsumer use bits 5,6 - system use (must preserve) bits 0-4 - server use (must preserve) UCHAR FileName[11]; Name of the returned file UCHAR ReservedForServer[5]; Client must not modify UCHAR ReservedForConsumer[4]; Server must not modify FileName is 8.3 format, with the three character extension left justified into FileName[9-11]. If the client is prior to the LANMAN1.0 dialect, the returned FileName should be uppercased. SMB_COM_SEARCH terminates when either the requested maximum number of entries that match the named file are found, or the end of directory is reached without the maximum number of matches being found. A response containing no entries indicates that no matching entries were found between the starting point of the search and the end of directory. There may be multiple matching entries in response to a single request as SMB_COM_SEARCH supports "wild cards" in the last component of FileName of the initial request. The wild card matching algorithm is described in the SMB_COM_DELETE description. Returned directory entries in the DirectoryInformationData field of the response each have the following format: Directory Information Field Description SMB_RESUME_KEY ResumeKey; Described above UCHAR FileAttributes; Attributes of the found file SMB_TIME LastWriteTime; Time file was last written SMB_DATE LastWriteDate; Date file was last written ULONG FileSize; Size of the file UCHAR FileName[13]; ASCII, space-filled null terminated FileName must conform to 8.3 rules, and is padded after the extension with 0x20 characters if necessary. If the client has negotiated a dialect prior to the LANMAN1.0 dialect, or if bit0 of the Flags2 SMB header field of the request is clear, the returned FileName should be uppercased. As can be seen from the above structure, SMB_COM_SEARCH can not return long filenames, and can not return UNICODE filenames. Files which have a size greater than 2^32 bytes should have the least significant 32 bits of their size returned in FileSize. OPEN_PRINT_FILE: Create Print Spool file This message is sent to create a new printer file which will be deleted once it has been closed and printed. Client Request Description UCHAR WordCount; Count of parameter words = 2 USHORT SetupLength; Length of printer setup data USHORT Mode; 0 = Text mode (DOS expands TABs) 1 = Graphics mode USHORT ByteCount; Count of data bytes; min = 2 UCHAR BufferFormat; 0x04 STRING IdentifierString[]; Identifier string Tid in the SMB header must refer to a printer resource type. SetupLength is the number of bytes in the first part of the resulting print spool file which contains printer-specific control strings. Mode can have the following values: 0 Text mode. The server may optionally expand tabs to a series of spaces. 1 Graphics mode. No conversion of data should be done by the server. IdentifierString can be used by the server to provide some sort of per-client identifying component to the print file. Server Response Description UCHAR WordCount; Count of parameter words = 1 USHORT Fid; File handle USHORT ByteCount; Count of data bytes = 0 Fid is the returned handle which may be used by subsequent write and close operations. When the file is finally closed, it will be sent to the spooler and printed. WRITE_PRINT_FILE: Write to Print File This message is sent to write bytes into a print spool file. Client Request Description UCHAR WordCount; Count of parameter words = 1 USHORT Fid; File handle USHORT ByteCount; Count of data bytes; min = 4 UCHAR BufferFormat; 0x01 -- Data block USHORT DataLength; Length of data UCHAR Data[]; Data Fid indicates the print spool file to be written, it must refer to a print spool file. ByteCount specifies the number of bytes to be written, and must be less than MaxBufferSize for the Tid specified. Data contains the bytes to append to the print spool file. The first SetupLength bytes in the resulting print spool file contain printer setup data. SetupLength is specified in the SMB_COM_OPEN_PRINT_FILE SMB request. Server Response Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 Servers which negotiate a protocol dialect of LANMAN1.0 or later also support the application of normal write requests to print spool files. CLOSE_PRINT_FILE: Close and Spool Print Job This message invalidates the specified file handle and queues the file for printing. Client Request Description UCHAR WordCount; Count of parameter words = 1 USHORT Fid; File handle USHORT ByteCount; Count of data bytes = 0 Fid referrs to a file previously created with SMB_COM_OPEN_PRINT_FILE. On successful completion of this request, the file is queued for printing by the server. Server Response Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 Servers which negotiate dialects of LANMAN1.0 and newer allow all the other types of Fid closing requests to invalidate the Fid and begin spooling. GET_PRINT_QUEUE: Get Printer Queue Entries This message obtains a list of the elements currently in the print queue on the server. Client Request Description UCHAR WordCount; Count of parameter words = 2 USHORT MaxCount; Max number of entries to return USHORT StartIndex; First queue entry to return USHORT ByteCount; Count of data bytes = 0 StartIndex specifies the first entry in the queue to return. MaxCount specifies the maximum number of entries to return, this may be a positive or negative number. A positive number requests a forward search, a negative number indicates a backward search. Server Response Description UCHAR WordCount; Count of parameter words = 2 USHORT Count; Number of entries returned USHORT RestartIndex; Index of entry after last returned USHORT ByteCount; Count of data bytes; min = 3 UCHAR BufferFormat; 0x01 -- Data block USHORT DataLength; Length of data UCHAR Data[]; Queue elements Count indicates how many entries were actually returned. RestartIndex is the index of the entry following the last entry returned; it may be used as the StartIndex in a subsequent request to resume the queue listing. The format of each returned queue element is: Queue Element Member Description SMB_DATE FileDate; Date file was queued SMB_TIME FileTime; Time file was queued UCHAR Status; Entry status. One of: 01 = held or stopped 02 = printing 03 = awaiting print 04 = in intercept 05 = file had error 06 = printer error 07-FF = reserved USHORT SpoolFileNumber; Assigned by the spooler ULONG SpoolFileSize; Number of bytes in spool file UCHAR Reserved; UCHAR SpoolFileName[16]; Client which created the spool file SMB_COM_GET_PRINT_QUEUE will return less than the requested number of elements only when the top or end of the queue is encountered. Support for this SMB is server optional. In particular, no current Microsoft client software issues this request. LOCK_AND_READ: Lock and Read Bytes This request is used to lock and "read ahead" the specified bytes of the file indicated by Fid in the SMB header Client Request Description UCHAR WordCount; Count of parameter words = 5 USHORT Fid; File handle USHORT Count; Count of bytes being requested ULONG Offset; Offset in file of first byte to read USHORT Remaining; Estimate of bytes to read if nonzero USHORT ByteCount; Count of data bytes = 0 Fid must refer to a disk file. Count specifies the requested number of bytes. Offset specifies the offset in the file of the first byte to be locked then read. Note that this offset is limited to 32 bits, so this client request is inappropriate for files having 64 bit offsets. Remaining is advisory. If the value is not zero, then it is taken as an estimate of the total number of bytes that will be read, including those read by this request. This additional information may be used by the server to optimize buffer allocation or read-ahead. Remaining is not included in the byte range to be locked. Server Response Description UCHAR WordCount; Count of parameter words = 5 USHORT Count; Count of bytes actually returned USHORT Reserved [4]; Reserved (must be 0) USHORT ByteCount; Count of data bytes UCHAR BufferFormat; 0x01 -- Data block USHORT DataLength; Length of data ByteCount is the number of bytes actually being returned. ByteCount may be less than the count requested only if a read specifies bytes beyond the current file size. In this case only the bytes that exist are returned. A read completely beyond the end of file results in a response of length zero. This is the only circumstance when a zero length response is generated. A count returned which is less than the count requested is the end of file indicator. As in the core SMB_LOCK_BYTE_RANGE request, if the lock can not be immediately granted an error should be returned to the client. If an error occurs on the lock, the bytes should not be read. If a Read requests more data than can be placed in a message of the max-xmit-size for the Tid specified, the server will abort the connection to the consumer. WRITE_AND_UNLOCK: Write Bytes and Unlock Range This request is used to first write the specified bytes and then unlock them. The locked portion of a file is "safe" to write behind because no other process can access the locked bytes until this process unlocks the bytes. Thus the consumer can buffer the locked bytes locally while they are being updated, then when the unlock request is received submit this protocol to both write and then unlock bytes. Whether or not this SMB is supported (along with SMB_COM_READ_AND_LOCK) is returned in bit0 of the Flags field of the negotiate response. Client Request Description UCHAR WordCount; Count of parameter words = 5 USHORT Fid; File handle USHORT Count; Number of bytes to be written ULONG Offset; Offset in file to begin write USHORT Remaining; Bytes remaining to satisfy request USHORT ByteCount; Count of data bytes UCHAR BufferFormat; 0x01 -- Data block USHORT DataLength; Length of data Count specifies the number of bytes to be written. Offset is the offset in the file of the first byte to be written. Since offset is 16 bits, this request is inappropriate for general use in a very large file. Remaining is advisory: if the value is not zero, then it is taken as an estimate of the number of bytes that will be written -including those written by this request. This additional information may be used by the server to optimize cache behavior. A value of 0 for Count is an error. If the request specifies a byte range beyond the current end of file, the file will be extended. Any bytes between the previous end of file and the requested offset are initialized to 0. Server Response Description UCHAR WordCount; Count of parameter words = 1 USHORT Count; Count of bytes actually written USHORT ByteCount; Count of data bytes = 0 Count in the response indicates the actual number of bytes written, and for successful writes will always equal the count in the request message. If the number of bytes written differs from the number requested and no error is indicated, then the server has no resources available with which to satisfy the complete write. If a Write sends a message of length greater than the MaxBufferSize for the TID specified, the server may abort the connection to the client. If an error occurs on the write, the bytes remain locked. READ_RAW: Read Raw The SMB_COM_READ_RAW protocol is used to maximize the performance of reading a large block of data from the server to the consumer. This request can be applied to files and named pipes. Client Request Description UCHAR WordCount; Count of parameter words = 8 USHORT Fid; File handle ULONG Offset; Offset in file to begin read USHORT MaxCount; Max bytes to return (max 65535) USHORT MinCount; Min bytes to return (normally 0) ULONG Timeout; Wait time if named pipe USHORT Reserved; USHORT ByteCount; Count of data bytes = 0 Fid identifies the resource being read, and may refer to a disk file or a named pipe. Timeout is the number of milliseconds to wait for completion Fid referrs to a named pipe. When the client issues this request, the client must guarantee that there is (and will be) no other request to the server for the duration of the SMB_COM_READ_RAW. The server will respond, in one send, with the raw data being read. Thus the client is able to request up to 65,535 bytes of data and receive it directly into the user’s buffer, since the server response has no header or trailer. Note that the amount of data requested is expected to be larger than the negotiated buffer size for this protocol. The reason that no other requests can be active on the client’s connection to the server for the duration of the request is that if other receives are present, there is normally no way to guarantee that the data will be received into the user space, rather the data may fill one (or more) of the other buffers. The number of bytes actually returned is determined by the length of the message the client receives as reported by the transport layer. If the request is to read more bytes than are present in the file, the read response will be of the length actually read from the file. If none of the requested bytes exist (EOF) or an error occurs on the read, the server responds with a zero byte send. Upon receipt of a zero length response, the client should send a different type of request to the server. The response to that read will then tell the client that EOF was hit or identify the error condition. The number of bytes returned may be less than the number requested only if a read specifies bytes beyond the current file size. In this case only the bytes that exist are returned. A read completely beyond the end of file results in a response of zero length. If the number of bytes returned is less than the number of bytes requested, this indicates end of file (if reading other than a standard blocked disk file, only ZERO bytes returned indicates end of file). The transport layer guarantees delivery of all response bytes to the client. Thus no SMB level confirmation protocol is required. If an error should occur at the clients end, all bytes must be received and thrown away. There is no need to inform the server of the error. This message was introduced with the LANMAN1.0 SMB dialect. Whether or not this request is supported is returned in the response to SMB_COM_NEGOTIATE. The flow for reading a sequential file using SMB_COM_READ_BOCK_RAW is: Client Request Server Response SMB_COM_OPEN file Success SMB_COM_READ_RAW raw data returned SMB_COM_READ_RAW more raw data returned SMB_COM_READ_RAW short (or 0 length) response returned SMB_COM_READ 0 bytes returned indicating EOF SMB_COM_CLOSE Success SMB_COM_READ_RAW has no way to return errors. Because the response is raw data only, a zero length response indicates EOF, a read error or that the server is temporarily out of large buffers. The consumer should then retry using a dofferent type of read request. This request will then either return the EOF condition, an error if the read is still failing, or will work if the problem was due to a temporary server condition. If the negotiated dialect is NT LM 0.12 or later, and the response to the SMB_COM_NEGOTIATE SMB has CAP_LARGE_FILES set in the Capabilities field, a new format of the SMB_COM_READ_RAW request is allowed which accomodates very large files having 64 bit offsets. Client Request Server Response UCHAR WordCount; Count of parameter words = 10 USHORT Fid; File handle ULONG Offset; Offset in file to begin read USHORT MaxCount; Max bytes to return (max 65535) USHORT MinCount; Min bytes to return (normally 0) ULONG Timeout; Wait time if named pipe USHORT Reserved; ULONG OffsetHigh; Upper 32 bits of offset USHORT ByteCount; Count of data bytes = 0 This form of the request is differented from the previous form of the request by the WordCount field. In this case, the final offset to read from is used by combining OffsetHigh and Offset, the resulting value can not be negative or the request will be rejected by the server. SMB_COM_READ_RAW can not be used over connectionless transports. READ_MPX: Read Block Multiplex The Read Block Multiplexed protocol is used to maximize the performance of reading a large block of data from the server to the client while still allowing other operations to take place between the client and server in the meantime. The NT server supports SMB_COM_READ_MPX only over connectionless transports. Client Request Description UCHAR WordCount; Count of parameter words = 8 USHORT Fid; File handle ULONG Offset; Offset in file to begin read USHORT MaxCount; Max bytes to return (max 65535) USHORT MinCount; Min bytes to return (normally 0) ULONG Reserved1; USHORT Reserved2; USHORT ByteCount; Count of data bytes = 0 Fid identifies the resource being read, and may refer to a disk file or a spooled printer. Timeout is the number of milliseconds to wait for completion Fid referrs to a named pipe. Server Response Description UCHAR WordCount; Count of parameter words = 8 ULONG Offset; Offset in file where data read USHORT Count; Total bytes being returned USHORT Reserved; USHORT DataCompactionMode; USHORT Reserved; USHORT DataLength; Number of data bytes this buffer USHORT DataOffset; Offset (from header start) to data USHORT ByteCount; Count of data bytes UCHAR Pad[]; Pad to SHORT or LONG UCHAR Data[]; Data (size = DataLength) Other requests may be active between the client and server. The server responds with the one or more response messages as defined above until the requested data amount has been returned. Each response contains the Pid and Mid of the original request and the Offset and Count of describing the placement of the data within the file. The client knows the maximum amount of data bytes which the server may return (from MaxCount of the request). Thus the client initializes its bytes expected variable to this value. The server then informs the client of the actual amount being returned via each part of the response in Count. The server may reduce the expected bytes by lowering the total number of bytes expected in Count in any response. When the amount of data bytes received (sum of the DataLength fields) equals the total amount of data bytes expected (smallest Count received), then the consumer has received all the data bytes. This allows the protocol to work even if the responses are received out of sequence. Note that DataLength being returned here can not be larger than the smaller of the consumer's buffer size (as specified in MaxBufferSize on the COM_SESSION_SETUP_AND_X client request SMB) or the server's buffer size (as specified in MaxBufferSize of the COM_NEGOTIATE server response SMB). As is true in SMB_COM_READ, the total number of bytes returned may be be less than the number requested only if a read specifies bytes beyond the current file size and Fid refers to a disk file. In this case only the bytes that exist are returned. A read completely beyond the end of file will result in a single response with a zero value in Count. If the total number of bytes returned is less than the number of bytes requested, this indicates end of file (if reading other than a standard blocked disk file, only ZERO bytes returned indicates end of file). Once started, the Read Block Multiplexed operation is expected to go to completion. The client is expected to receive all the responses generated by the server. Conflicting commands (such as file close) must not be sent to the server while a multiplexed operation is in progress. The flow for the SMB_COM_READ_MPX protocol is: consumer -----------------------------> Read MPX. request >------------------------------> server consumer <--------------------< Read MPX response 1 with data <----------------------- server consumer <--------------------< Read MPX response 2 with data <----------------------- server . . . consumer <--------------------< Read MPX response n with data <---------------------- server WRITE_RAW: Write Raw Bytes The Write Block Raw protocol is used to maximize the performance of writing a large block of data from the consumer to the server. The Write Block Raw command's scope includes files, Named Pipes, and spooled output (can be used in place COM_WRITE_PRINT_FILE ). Client Request Description UCHAR WordCount; Count of parameter words = 12 USHORT Fid; File handle USHORT Count; Total bytes, including this buffer USHORT Reserved; ULONG Offset; Offset in file to begin write ULONG Timeout; USHORT WriteMode; Write mode: bit 0 - complete write to disk and send final result response bit 1 - return Remaining (pipe/dev) (see WriteAndX for #defines) ULONG Reserved2; USHORT DataLength; Number of data bytes this buffer USHORT DataOffset; Offset (from header start) to data USHORT ByteCount; Count of data bytes UCHAR Pad[]; Pad to SHORT or LONG UCHAR Data[]; Data (# = DataLength) First Server Response Description UCHAR WordCount; Count of parameter words = 1 USHORT Remaining; Bytes remaining to be read if pipe USHORT ByteCount; Count of data bytes = 0 Final Server Response Description UCHAR Command (in SMB header) SMB_COM_WRITE_COMPLETE UCHAR WordCount; Count of parameter words = 1 USHORT Count; Total number of bytes written USHORT ByteCount; Count of data bytes = 0 The first response format will be that of the final server response in the case where the server gets an error while writing the data sent along with the request. Thus Count is the number of bytes which did get written any time an error is returned. If an error occurs after the first response has been sent allowing the client to send the remaining data, the final response should not be sent unless write through is set. Rather the server should return this "write behind" error on the next access to the Fid. The client must guarantee that there is (and will be) no other request on the connection for the duration of this request. The server will reserve enough resources to receive the data and respond with a response SMB as defined above. The client then sends the raw data in one send. Thus the server is able to receive up to 65,535 bytes of data directly into the server buffer. The amount of data transferred is expected to be larger than the negotiated buffer size for this protocol. The reason that no other requests can be active on the connection for the duration of the request is that if other receives are present on the connection, there is normally no way to guarantee that the data will be received into the correct server buffer, rather the data may fill one (or more) of the other buffers. Also if the client is sending other requests on the connection, a request may land in the buffer that the server has allocated for the this SMB’s data. Whether or not SMB_COM_WRITE_RAW is supported is returned in the response to SMB_COM_NEGOTIATE. SMB_COM_WRITE_RAW is not supported for connectionless clients. When write through is not specified ((WriteMode & 01) == 0) this SMB is assumed to be a form of write behind. The transport layer guarantees delivery of all secondary requests from the client. Thus no "got the data you sent" SMB is needed. If an error should occur at the server end, all bytes must be received and thrown away. If an error occurs while writing data to disk such as disk full, the next access of the file handle (another write, close, read, etc.) will return the fact that the error occurred. If write through is specified ((WriteMode & 01) != 0), the server will receive the data, write it to disk and then send a final response indicating the result of the write. The total number of bytes written is also returned in this response in the Count field. The flow for the SMB_COM_WRITE_RAW SMB is: client -----------> SMB_COM_WRITE_RAW request (optional data) >----------> server client <------------------------< OK send (more) data <--------------------------- server client -------------------------------> raw data >----------------------------------> server client <-------------< data on disk or error (write through only) <-------------- server This protocol is set up such that the SMB_COM_WRITE_RAW request may also carry data. This is an optimization in that up to the server's buffer size (MaxCount from SMB_COM_NEGOTIATE response), minus the size of the SMB_COM_WRITE_RAW SMB request, may be sent along with the request. Thus if the server is busy and unable to support the raw write of the remaining data, the data sent along with the request has been delivered and need not be sent again. The server will write any data sent in the request (and wait for it to be on the disk or device if write through is set), prior to sending the response. The specific responses error class ERRSRV, error codes ERRusempx and ERRusestd, indicate that the server is temporarily out of the resources needed to support the raw write of the remaining data, but that any data sent along with the request has been successfully written. The client should then write the remaining data using a different type of SMB write request, or delay and retry using SMB_COM_WRITE_RAW. If a write error occurs writing the initial data, it will be returned and the write raw request is implicitly denied. The return field Remaining is returned for named pipes only. It is used to return the number of bytes currently available in the pipe. This information can then be used by the client to know when a subsequent (non blocking) read of the pipe may return some data. Of course when the read request is actually received by the server there may be more or less actual data in the pipe (more data has been written to the pipe / device or another reader drained it). If the information is currently not available or the request is NOT for a pipe or the server does not support this feature, a -1 value should be returned. If the negotiated dialect is NT LM 0.12 or later, and the response to the SMB_COM_NEGOTIATE SMB has CAP_LARGE_FILES set in the Capabilities field, an additional request format is allowed which accomodates very large files having 64 bit offsets: Client Request Description UCHAR WordCount; Count of parameter words = 14 USHORT Fid; File handle USHORT Count; Total bytes, including this buffer USHORT Reserved; ULONG Offset; Offset in file to begin write ULONG Timeout; USHORT WriteMode; Write mode: bit 0 - complete write to disk and send final result response bit 1 - return Remaining (pipe/dev) ULONG Reserved2; USHORT DataLength; Number of data bytes this buffer USHORT DataOffset; Offset (from header start) to data ULONG OffsetHigh; Upper 32 bits of offset USHORT ByteCount; Count of data bytes UCHAR Pad[]; Pad to SHORT or LONG UCHAR Data[]; Data (# = DataLength) In this case the final offset in the file is formed by combining OffsetHigh and Offset, the resulting offset must not be negative. WRITE_MPX: Write Block Multiplex Client Request Description UCHAR WordCount; Count of parameter words = 12 USHORT Fid; File handle USHORT Count; Total bytes, including this buffer USHORT Reserved; ULONG Offset; Offset in file to begin write ULONG Timeout; milliseconds to wait for completion USHORT WriteMode; Write mode: bit 0 - complete write to disk and send final result response bit 1 - return Remaining bit 7 - Connectionless mode ULONG RequestMask; Connectionless mode mask USHORT DataLength; Number of data bytes this buffer USHORT DataOffset; Offset (from header start) to data USHORT ByteCount; Count of data bytes UCHAR Pad[]; Pad to SHORT or LONG UCHAR Data[]; Data (# = DataLength) Server Response Description UCHAR WordCount; Count of parameter words = 1 ULONG ResponseMask; OR of all masks received USHORT ByteCount; Count of data bytes = 0 SMB_COM_WRITE_MPX is used to maximize the performance of writing a large block of data from the consumer to the server. The NT server supports SMB_COM_WRITE_MPX only over connectionless transports, consequently bit7 of WriteMode in the request must be set. Fid in the request must refer to either a file or a spooled printer. Mask contains a bit mask indicating where in the transfer that the SMB belongs. The response which contains the logical OR of all of the Mask values received and is always generated. All in this exchange use the same SMB header Mid value but only final message is a connectionless sequenced request (SequenceNumber is non-zero). The server keeps a ResponseMask which is the logical or-ing of the RequestMask value contained in each SMB_COM_WRITE_MPX received since the last sequenced SMB_COM_WRITE_MPX. The server only responds to the final (sequenced) command, and this response contains the accumulated ResponseMask. The client uses the ResponseMask received to determine which packets, if any, must be retransmitted. The server imposes no restrictions on the values in the mask nor upon the order or contiguity of the data being sent. The client uses this behavior to only send the missing parts in the next write sequence when retransmitting. The next SMB_COM_WRITE_MPX sequence sent must use a new SequenceNumber value or the server will incorrectly respond with the mask from the previous SMB_COM_WRITE_MPX command. The flow is: Client Sequence Number Server SMB_COM_WRITE_MP X 0 ® SMB_COM_WRITE_MP X 0 ® ... SMB_COM_WRITE_MP X S ® S SMB_COM_WRITE_MPX OK SMB_COM_WRITE_MP X 0 ® SMB_COM_WRITE_MP X 0 ® .... SMB_COM_WRITE_MP X S+1 ® S+1 SMB_COM_WRITE_MPX OK Other SMB requests can intervene during this protocol exchange. A server response will be generated only after the sequenced SMB_COM_WRITE_MPX has been received unless this SMB is received over a connection oriented transport (in which case the error response is immediately sent). At the time of the request, the client knows the number of data bytes expected to be sent and passes this information to the server in Count. The server can use this information to reserve buffer space, if possible. If bit0 of WriteMode is clear, the request assumed to be a form of write behind on the part of the client. If an error occurs while writing data to disk such as disk full, the next access of the file handle (another write, close, read, etc.) will return the fact that the error occurred. If bit0 of WriteMode is set, the server will collect all the data, write it to disk and then send a final response indicating the result of the write . The total number of bytes written is also returned in this response. SET_INFORMATION2: Set File Information Client Request Description UCHAR WordCount; Count of parameter words = 7 USHORT Fid; File handle SMB_DATE CreationDate; SMB_TIME CreationTime; SMB_DATE LastAccessDate; SMB_TIME LastAccessTime; SMB_DATE LastWriteDate; SMB_TIME LastWriteTime; USHORT ByteCount; Count of data bytes = 0 SMB_COM_SET_INFORMATION2 sets information about the file represented by Fid. The target file is updated from the values specified. A date or time value or zero indicates to leave that specific date and time unchanged. Server Response Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 Fid must be open with (at least) write permission. QUERY_INFORMATION2: Get File Information This SMB is gets information about the file represented by Fid. Client Request Description UCHAR WordCount; Count of parameter words = 2 USHORT Fid; File handle USHORT ByteCount; Count of data bytes = 0 Server Response Description UCHAR WordCount; Count of parameter words = 11 SMB_DATE CreationDate; SMB_TIME CreationTime; SMB_DATE LastAccessDate; SMB_TIME LastAccessTime; SMB_DATE LastWriteDate; SMB_TIME LastWriteTime; ULONG FileDataSize; File end of data ULONG FileAllocationSize; File allocation size USHORT FileAttributes; USHORT ByteCount; Count of data bytes; min = 0 The file being interrogated is specified by Fid, which must possess at least read permission. FileAttributes are described in the File Attribute Encoding section elsewhere in this document. LOCKING_ANDX: Lock or UnLock Bytes SMB_COM_LOCKING_ANDX allows both locking and/or unlocking of file range(s). Client Request Description UCHAR WordCount; Count of parameter words = 8 UCHAR AndXCommand; Secondary (X) command; 0xFF = none UCHAR AndXReserved; Reserved (must be 0) USHORT AndXOffset; Offset to next command WordCount USHORT Fid; File handle UCHAR LockType; See LockType table below UCHAR OplockLevel; The new oplock level ULONG Timeout; Milliseconds to wait for unlock USHORT NumberOfUnlocks; Num. unlock range structs following USHORT NumberOfLocks; Num. lock range structs following USHORT ByteCount; Count of data bytes LOCKING_ANDX_RANGE Unlocks[]; Unlock ranges LOCKING_ANDX_RANGE Locks[]; Lock ranges LockType Flag Name Value Description LOCKING_ANDX_SHARED_LOCK 0x01 Readonly lock LOCKING_ANDX_OPLOCK_RELEASE 0x02 Oplock break notification LOCKING_ANDX_CHANGE_LOCKTYPE 0x04 Change lock type LOCKING_ANDX_CANCEL_LOCK 0x08 Cancel outstanding request LOCKING_ANDX_LARGE_FILES 0x10 Large file locking format LOCKING_ANDX_RANGE Format USHORT Pid; PID of process "owning" lock ULONG Offset; Ofset to bytes to [un]lock ULONG Length; Number of bytes to [un]lock Large File LOCKING_ANDX_RANGE Format USHORT Pid; PID of process "owning" lock USHORT Pad; Pad to DWORD align (mbz) ULONG OffsetHigh; Ofset to bytes to [un]lock (high) ULONG OffsetLow; Ofset to bytes to [un]lock (low) ULONG LengthHigh; Number of bytes to [un]lock (high) ULONG LengthLow; Number of bytes to [un]lock (low) Server Response Description UCHAR WordCount; Count of parameter words = 2 UCHAR AndXCommand; Secondary (X) command; 0xFF = none UCHAR AndXReserved; Reserved (must be 0) USHORT AndXOffset; Offset to next command WordCount USHORT ByteCount; Count of data bytes = 0 Locking is a simple mechanism for excluding other processes read/write access to regions of a file. The locked regions can be anywhere in the logical file. Locking beyond endof-file is permitted. Any process using the Fid specified in this request’s Fid has access to the locked bytes, other processes will be denied the locking of the same bytes. The proper method for using locks is not to rely on being denied read or write access on any of the read/write protocols but rather to attempt the locking protocol and proceed with the read/write only if the locks succeeded. Locking a range of bytes will fail if any subranges or overlapping ranges are locked. In other words, if any of the specified bytes are already locked, the lock will fail. If NumberOfUnlocks is non-zero, the Unlocks vector contains NumberOfUnlocks elements. Each element requests that a lock at Offset of Length be released. If NumberOfLocks is nonzero, the Locks vector contains NumberOfLocks elements. Each element requests the acquisition of a lock at Offset of Length. Timeout is the maximum amount of time to wait for the byte range(s) specified to become unlocked. A timeout value of 0 indicates that the server should fail immediately if any lock range specified is locked. A timeout value of -1 indicates that the server should wait as long as it takes for each byte range specified to become unlocked so that it may be again locked by this protocol. Any other value of smb_timeout specifies the maximum number of milliseconds to wait for all lock range(s) specified to become available. If any of the lock ranges timeout because of the area to be locked is already locked (or the lock fails), the other ranges in the protocol request which were successfully locked as a result of this protocol will be unlocked (either all requested ranges will be locked when this protocol returns to the consumer or none). If LockType has the LOCKING_ANDX_SHARED_LOCK flag set, the lock is specified as a shared lock. Locks for both read and write (where LOCKING_ANDX_SHARED_LOCK is clear) should be prohibited, but other shared locks should be permitted. If shared locks can not be supported by a server, the server should map the lock to a lock for both read and write. Closing a file with locks still in force causes the locks to be released in no defined order. If LockType has the LOCKING_ANDX_LARGE_FILES flag set and if the negotiated protocol is NT LM 0.12 or later, then the Locks and Unlocks vectors are in the Large File LOCKING_ANDX_RANGE format. This allows specification of 64 bit offsets for very large files. If the one and only member of the Locks vector has the LOCKING_ANDX_CANCEL_LOCK flag set in the LockType field, the client is requesting the server to cancel a previously requested, but not yet responded to, lock. If LockType has the LOCKING_ANDX_CHANGE_LOCKTYPE flag set, the client is requesting that the server atomically change the lock type from a shared lock to an exclusive lock or vice versa. If the server can not do this in an atomic fashion, the server must reject this request. NT and W95 servers do not support this capability. Oplocks are described in the Opportunistic Locks section elsewhere in this document. A client requests an oplock by setting the appropriate bit in the SMB_COM_OPEN_ANDX request when the file is being opened in a mode which is not exclusive. The server responds by setting the appropriate bit in the response SMB indicating whether or not the oplock was granted. By granting the oplock, the server tells the client the file is currently only being used by this one client process at the current time. The client can therefore safely do read ahead and write behind as well as local caching of file locks knowing that the file will not be accessed/changed in any way by another process while the oplock is in effect. The client will be notified when any other process attempts to open or modify the oplocked file. When another user attempts to open or otherwise modify the file which a client has oplocked, the server delays the second attempt and notifies the client via an SMB_LOCKING_ANDX SMB asynchronously sent from the server to the client. This message has the LOCKING_ANDX_OPLOCK_RELEASE flag set indicating to the client that the oplock is being broken. OplockLevel indicates the type of oplock the client now owns. If OplockLevel is 0, the client possesses no oplocks on the file at all, if OplockLevel is 1 the client possesses a Level II oplock. The client is expected to flush any dirty buffers to the server, submit any file locks and respond to the server with either an SMB_LOCKING_ANDX SMB having the LOCKING_ANDX_OPLOCK_RELEASE flag set, or with a file close if the file is no longer in use by the client. If the client sends an SMB_LOCKING_ANDX SMB with the LOCKING_ANDX_OPLOCK_RELEASE flag set and NumberOfLocks is zero, the server does not send a response. Since a close being sent to the server and break oplock notification from the server could cross on the wire, if the client gets an oplock notification on a file which it does not have open, that notification should be ignored. Due to timing, the client could get an “oplock broken” notification in a user's data buffer as a result of this notification crossing on the wire with a SMB_COM_READ_RAW request. The client must detect this (use length of msg, "FFSMB", MID of -1 and Command of SMB_COM_LOCKING_ANDX) and honor the “oplock broken” notification as usual. The server must also note on receipt of an SMB_COM_READ_RAW request that there is an outstanding (unanswered) "oplock broken” notification to the client and return a zero length response denoting failure of the read raw request. The client should (after responding to the “oplock broken” notification), use a standard read protocol to redo the read request. This allows a file to actually contain data matching an “oplock broken” notification and still be read correctly. The entire message sent and received including the optional second protocol must fit in the negotiated max transfer size. The following are the only valid SMB commands for AndXCommand for SMB_COM_LOCKING_ANDX: SMB_COM_READ SMB_COM_READ_ANDX SMB_COM_WRITE SMB_COM_WRITE_ANDX SMB_COM_FLUSH MOVE: Rename File The source file is copied to the destination and the source is subsequently deleted. Client Request Description UCHAR WordCount; Count of parameter words = 3 USHORT Tid2; Second (target) file id USHORT OpenFunction; what to do if target file exists USHORT Flags; Flags to control move operations: 0 - target must be a file 1 - target must be a directory 2 - reserved (must be 0) 3 - reserved (must be 0) 4 - verify all writes USHORT ByteCount; Count of data bytes; min = 2 UCHAR Format1; 0x04 STRING OldFileName[]; Old file name UCHAR FormatNew; 0x04 STRING NewFileName[]; New file name OldFileName is copied to NewFileName, then OldFileName is deleted. Both OldFileName and NewFileName must refer to paths on the same server. NewFileName can refer to either a file or a directory. All file components except the last must exist; directories will not be created. NewFileName can be required to be a file or a directory by the Flags field. The Tid in the header is associated with the source while Tid2 is associated with the destination. These fields may contain the same or differing valid values. Tid2 can be set to -1 indicating that this is to be the same Tid as in the SMB header. This allows use of the move protocol with SMB_TREE_CONNECT_ANDX. Server Response Description UCHAR WordCount; Count of parameter words = 1 USHORT Count; Number of files moved USHORT ByteCount; Count of data bytes; min = 0 UCHAR ErrorFileFormat; 0x04 (only if error) STRING ErrorFileName[]; Pathname of file where error occurred The source path must refer to an existing file or files. Wildcards are permitted. Source files specified by wildcards are processed until an error is encountered. If an error is encountered, the expanded name of the file is returned in ErrorFileName. Wildcards are not permitted in NewFileName. OpenFunction controls what should happen if the destination file exists. If (OpenFunction & 0x30) == 0, the operation should fail if the destination exists. If (OpenFunction & 0x30) == 0x20, the destination file should be overwritten. COPY: Copy File Client Request Description UCHAR WordCount; Count of parameter words = 3 USHORT Tid2; Second (target) path TID USHORT OpenFunction; What to do if target file exists USHORT Flags; Flags to control copy operation: bit 0 - target must be a file bit 1 - target must ba a dir. bit 2 - copy target mode: 0 = binary, 1 = ASCII bit 3 - copy source mode: 0 = binary, 1 = ASCII bit 4 - verify all writes bit 5 - tree copy USHORT ByteCount; Count of data bytes; min = 2 UCHAR SourceFileNameFormat; 0x04 STRING SourceFileName; Pathname of source file UCHAR TargetFileNameFormat; 0x04 STRING TargetFileName; Pathname of target file The file at SourceName is copied to TargetFileName, both of which must refer to paths on the same server. The Tid in the header is associated with the source while Tid2 is associated with the destination. These fields may contain the same or differing valid values. Tid2 can be set to -1 indicating that this is to be the same Tid as in the SMB header. This allows use of the move protocol with SMB_TREE_CONNECT_ANDX. Server Response Description UCHAR WordCount; Count of parameter words = 1 USHORT Count; Number of files copied USHORT ByteCount; Count of data bytes; min = 0 UCHAR ErrorFileFormat; 0x04 (only if error) STRING ErrorFileName; The source path must refer to an existing file or files. Wildcards are permitted. Source files specified by wildcards are processed until an error is encountered. If an error is encountered, the expanded name of the file is returned in ErrorFileName. Wildcards are not permitted in TargetFileName. TargetFileName can refer to either a file or a directory. The destination can be required to be a file or a directory by the bits in Flags. If neither bit0 nor bit1 are set, the destination may be either a file or a directory. Flags also controls the copy mode. In a binary copy for the source, the copy stops the first time an EOF (control-Z) is encountered. In a binary copy for the target, the server must make sure that there is exactly one EOF in the target file and that it is the last character of the file. OpenFunction controls what should happen if the destination file exists, and has the following bit mapping: bits: 1111 11 5432 1098 7654 3210 rrrr rrrr rrrC rrOO where: O - Open (action to be taken if destination file exists). 0 - Fail. 1 - Append file. 2 - Truncate file. r - reserved (must be zero). C - Create (action to be taken if destination file does not exist). 0 -- Fail. 1 -- Create file. If the destination is a file and the source contains wildcards, the destination file will either be truncated or appended to at the start of the operation depending on bits in OpenFunction . Subsequent files will then be appended to the file. If the negotiated dialect is LM1.2X002 or later, bit5 of Flags is used to specify a tree copy on the remote server. When this option is selected the destination must not be an existing file and the source mode must be binary. A request with bit5 set and either bit0 or bit3 set is therefore an error. When the tree copy mode is selected, the Count field in the server response is undefined. ECHO: Ping the Server This request is used to test the connection to the server, and to see if the server is still responding. Client Request Description UCHAR WordCount; Count of parameter words = 1 USHORT EchoCount; Number of times to echo data back USHORT ByteCount; Count of data bytes; min = 1 UCHAR Buffer[1]; Data to echo Server Response Description UCHAR WordCount; Count of parameter words = 1 USHORT SequenceNumber; Sequence number of this echo USHORT ByteCount; Count of data bytes; min = 4 UCHAR Buffer[1]; Echoed data Each response echos the data sent, though ByteCount may indicate no data If EchoCount is zero, no response is sent. Tid in the SMB header is ignored, so this request may be sent to the server even if there are no valid tree connections to the server. The flow for the ECHO protocol is: Client Request Server Response Echo Request (EchoCount == n) ® Echo Response 1 Echo Response 2 Echo Response n If a client is communicating to the server over a connectionless transport, this SMB can be used to ensure there is some activity on the connection as required in the Connectionless Transports section elsewhere in this document. WRITE_AND_CLOSE: Write Bytes and Close File This request is used to first write the specified bytes and then close the file. Client Request Description UCHAR WordCount; Count of parameter words = 6 USHORT Fid; File handle USHORT Count; Number of bytes to write ULONG Offset; Offset in file of first byte to write SMB_TIME LastWriteTime; Time of last write USHORT ByteCount; 1 (for pad) + value of Count UCHAR Pad; To force to doubleword boundary UCHAR Buffer[ Count ]; Data to write Client Request Description UCHAR WordCount; Count of parameter words = 12 USHORT Fid; File handle USHORT Count; Number of bytes to write ULONG Offset; Offset in file of first byte to write SMB_TIME LastWriteTime; Time of last write SMB_DATE LastWriteDate; Date of last write ULONG Reserved[3]; Reserved, must be 0 USHORT ByteCount; 1 (for pad) + value of Count UCHAR Pad; To force to doubleword boundary UCHAR Buffer[Count]; Data to write Server Response Description UCHAR WordCount; Count of parameter words = 1 USHORT Count; Count of bytes actually written USHORT ByteCount; Count of data bytes = 0 Since clients can formulate the request in either of two ways, WordCount must be used in order to correctly locate the data to be written. Count specifies the number of bytes to be written. Offset is the offset in the file of the first byte to be written. Since Offset is 32 bits, this request is inappropriate for general use in a very large file. If LastWriteTime and LastWriteDate are 0, the server should allow its local operating system to set the file’s times. Otherwise, the server should set the time to the values requested. Failure to set the times, even if requested by the client in this message, should not result in an error response from the server. If Count is 0, the file is truncated (or extended) to Offset. If an error occurs on the write, the file should still be closed. OPEN_ANDX: Open File And X Client Request Description UCHAR WordCount; Count of parameter words = 15 UCHAR AndXCommand; Secondary (X) command; 0xFF = none UCHAR AndXReserved; Reserved (must be 0) USHORT AndXOffset; Offset to next command WordCount USHORT Flags; Additional information: bit set- 0 - return additional info 1 - exclusive oplock requested 2 - batch oplock requested USHORT DesiredAccess; File open mode USHORT SearchAttributes; USHORT FileAttributes; SMB_TIME CreationTime; SMB_DATE CreationDate; USHORT OpenFunction; Action to take if file exists ULONG AllocationSize; Bytes to reserve on create or truncate ULONG Reserved[2]; Must be 0 USHORT ByteCount; Count of data bytes; min = 1 UCHAR BufferFormat 0x04 STRING FileName; Server Response Description UCHAR WordCount; Count of parameter words = 15 UCHAR AndXCommand; Secondary (X) command; 0xFF = none UCHAR AndXReserved; Reserved (must be 0) USHORT AndXOffset; Offset to next command WordCount USHORT Fid; File handle USHORT FileAttributes; SMB_TIME LastWriteTime; SMB_DATE LastWriteDate; ULONG DataSize; Current file size USHORT GrantedAccess; Access permissions actually allowed USHORT FileType; Type of file opened USHORT DeviceState; State of the named pipe USHORT Action; Action taken ULONG ServerFid; Server unique file id USHORT Reserved; Reserved (must be 0) USHORT ByteCount; Count of data bytes = 0 DesiredAccess describes the access the client desires for the file; the encoding of this field is described in the Access Mode Encoding section elsewhere in this document. OpenFunction specifies the action to be taken depending on whether or not the file exists. This word has the following format: bits: 1111 11 5432 1098 7654 3210 rrrr rrrr rrrC rrOO where: C - Create (action to be taken if file does not exist). 0 -- Fail. 1 -- Create file. r - reserved (must be zero). O - Open (action to be taken if file exists). 0 - Fail. 1 - Open file. 2 - Truncate file. Action in the response specifies the action as a result of the Open request. It has the following format: bits: 1111 11 5432 1098 7654 3210 Lrrr rrrr rrrr rrOO where: L - Lock (single user total file lock status). 0 -- file opened by another user (or mode not supported by server). 1 -- file is opened only by this user at the present time. r - reserved (must be zero). O - Open (action taken on Open). 1 - The file existed and was opened. 2 - The file did not exist but was created. 3 - The file existed and was truncated. SearchAttributes indicates the attributes that the file must have to be found while searching to see if it exists. The encoding of this field is described in the File Attribute Encoding section elsewhere in this document. If SearchAttributes is zero then only normal files are returned. If the system file, hidden or directory attributes are specified then the search is inclusive -- both the specified type(s) of files and normal files are returned. FileType returns the kind of resource actually opened: Name Value Description FileTypeDisk 0 Disk file or directory as defined in the attribute field FileTypeByteModePipe 1 Named pipe in byte mode FileTypeMessageModePipe 2 Named pipe in message mode FileTypePrinter 3 Spooled printer FileTypeUnknown 0xFFFF Unrecognized resource type DeviceState is applicable only if the FileType is FileTypeByteModePipe or FileTypeMessageModePipe and is encoded as follows: 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 B E * * T T R R where: B - Blocking - 0 => reads/writes block if no data available 1 => reads/writes return immediately if no data E - Endpoint - 0 => consumer end of pipe 1 => server end of pipe TT - Type of pipe - 00 => pipe is a byte stream pipe 01 => pipe is a message pipe RR - Read Mode - 00 => Read pipe as a byte stream 01 => Read messages from pipe If bit0 of Flags is clear, the FileAttributes, LastWriteTime, LastWriteDate, DataSize, FileType, and DeviceState have indeterminate values in the response. This SMB can request an oplock on the opened file. Oplocks are fully described in the Oplocks section elsewhere in this document, and there is also discussion of oplocks in the SMB_COM_LOCKING_ANDX SMB description. Bit1 and bit2 of the Flags field are used to request oplocks during open. The following SMBs may follow SMB_COM_OPEN_ANDX: SMB_COM_READ SMB_COM_READ_ANDX SMB_COM_IOCTL NT_CREATE_ANDX: Create File This command is used to create or open a file or a directory. Many of the parameters are passed directly to the NT open functions. Client Request Description UCHAR WordCount; Count of parameter words = 24 UCHAR AndXCommand; Secondary command; 0xFF = None UCHAR AndXReserved; Reserved (must be 0) USHORT AndXOffset; Offset to next command wordcount UCHAR Reserved; Reserved (must be 0) USHORT NameLength; Length of Name[] in bytes ULONG Flags; Create bit set: 0x02 - Request an oplock 0x04 - Request a batch oplock 0x08 - Target of open must be directory ULONG RootDirectoryFid; If non-zero, open is relative to this directory ACCESS_MASK DesiredAccess; NT access desired LARGE_INTEGER AllocationSize; Initial allocation size ULONG FileAttributes; File attributes for creation ULONG ShareAccess; Type of share access ULONG CreateDisposition; Action to take if file exists or not ULONG CreateOptions; Options to use if creating a file ULONG ImpersonationLevel; Security QOS information UCHAR SecurityFlags; Security QOS information 1 - Dynamic Tracking 2 - Effective only USHORT ByteCount; Length of byte parameters STRING Name[]; File to open or create Server Response Description UCHAR WordCount; Count of parameter words = 26 UCHAR AndXCommand; Secondary command; 0xFF = None UCHAR AndXReserved; MBZ USHORT AndXOffset; Offset to next command wordcount UCHAR OplockLevel; The oplock level granted USHORT Fid; The file ID ULONG CreateAction; The action taken TIME CreationTime; The time the file was created TIME LastAccessTime; The time the file was accessed TIME LastWriteTime; The time the file was last written TIME ChangeTime; The time the file was last changed ULONG FileAttributes; The file attributes LARGE_INTEGER AllocationSize; The number of byes allocated LARGE_INTEGER EndOfFile; The end of file offset USHORT FileType; USHORT DeviceState; state of IPC device (e.g. pipe) BOOLEAN Directory; TRUE if this is a directory USHORT ByteCount; = 0 The following SMBs may follow SMB_COM_NT_CREATE_ANDX: SMB_COM_READ SMB_COM_READ_ANDX SMB_COM_IOCTL READ_ANDX: Read Data Client Request Description UCHAR WordCount; Count of parameter words = 10 UCHAR AndXCommand; Secondary (X) command; 0xFF = none UCHAR AndXReserved; Reserved (must be 0) USHORT AndXOffset; Offset to next command WordCount USHORT Fid; File handle ULONG Offset; Offset in file to begin read USHORT MaxCount; Max number of bytes to return USHORT MinCount; Min number of bytes to return ULONG Reserved; Must be 0 USHORT Remaining; Bytes remaining to satisfy request USHORT ByteCount; Count of data bytes = 0 Large File Client Request Description UCHAR WordCount; Count of parameter words = 12 UCHAR AndXCommand; Secondary (X) command; 0xFF = none UCHAR AndXReserved; Reserved (must be 0) USHORT AndXOffset; Offset to next command WordCount USHORT Fid; File handle ULONG Offset; Offset in file to begin read USHORT MaxCount; Max number of bytes to return USHORT MinCount; Min number of bytes to return ULONG Reserved; Must be 0 USHORT Remaining; Bytes remaining to satisfy request ULONG OffsetHigh; Upper 32 bits of offset USHORT ByteCount; Count of data bytes = 0 Server Response Description UCHAR WordCount; Count of parameter words = 12 UCHAR AndXCommand; Secondary (X) command; 0xFF = none UCHAR AndXReserved; Reserved (must be 0) USHORT AndXOffset; Offset to next command WordCount USHORT Remaining; Bytes remaining to be read USHORT DataCompactionMode; USHORT Reserved; Reserved (must be 0) USHORT DataLength; Number of data bytes (min = 0) USHORT DataOffset; Offset (from header start) to data USHORT Reserved[5]; Reserved (must be 0) USHORT ByteCount; Count of data bytes UCHAR Pad[]; UCHAR Data[ DataLength]; Data from resource If the negotiated dialect is NT LM 0.12 or later, the client may use the Large File version of the request. This version allows specification of 64 bit file offsets. MinCount in the request is valid only if Fid refers to a named pipe. MinCount informs the server that at least MinCount bytes should be returned, if possible. Remaining in the response is valid for pipes only. It is used to return the number of bytes currently available in the pipe excluding the bytes returned in this response. This information can then be used by the client to know when a subsequent (non blocking) read of the pipe may return some data. When a future read request is actually received by the server there may be more or less actual data in the pipe (more data has been written to the pipe or another reader drained it). If the information is currently not available or the request is NOT for a pipe, a -1 value should be returned. DataCompactionMode. SMB_COM_CLOSE is the only valid command for AndXCommand. WRITE_ANDX: Write Bytes to file or resource Client Request Description UCHAR WordCount; Count of parameter words = 12 UCHAR AndXCommand; Secondary (X) command; 0xFF = none UCHAR AndXReserved; Reserved (must be 0) USHORT AndXOffset; Offset to next command WordCount USHORT Fid; File handle ULONG Offset; Offset in file to begin write ULONG Reserved; Must be 0 USHORT WriteMode; Write mode: 0 - write through 1 - return Remaining 2 - use WriteRawNamedPipe (n. pipes) 3 - "this is the start of the msg" USHORT Remaining; Bytes remaining to satisfy request USHORT Reserved; USHORT DataLength; Number of data bytes in buffer (>=0) USHORT DataOffset; Offset to data bytes USHORT ByteCount; Count of data bytes UCHAR Pad[]; Pad to SHORT or LONG UCHAR Data[DataLength]; Data to write Large File Client Request Description UCHAR WordCount; Count of parameter words = 14 UCHAR AndXCommand; Secondary (X) command; 0xFF = none UCHAR AndXReserved; Reserved (must be 0) USHORT AndXOffset; Offset to next command WordCount USHORT Fid; File handle ULONG Offset; Offset in file to begin write ULONG Reserved; Must be 0 USHORT WriteMode; Write mode bits: 0 - write through 1 - return Remaining 2 - use WriteRawNamedPipe (n. pipes) 3 - "this is the start of the msg" USHORT Remaining; Bytes remaining to satisfy request USHORT Reserved; USHORT DataLength; Number of data bytes in buffer (>=0) USHORT DataOffset; Offset to data bytes ULONG OffsetHigh; Upper 32 bits of offset USHORT ByteCount; Count of data bytes UCHAR Pad[]; Pad to SHORT or LONG UCHAR Data[DataLength]; Data to write Server Response Description UCHAR WordCount; Count of parameter words = 6 UCHAR AndXCommand; Secondary (X) command; 0xFF = none UCHAR AndXReserved; Reserved (must be 0) USHORT AndXOffset; Offset to next command WordCount USHORT Count; Number of bytes written USHORT Remaining; Bytes remaining to be read in pipe ULONG Reserved; USHORT ByteCount; Count of data bytes = 0 A ByteCount of 0 does not truncate the file. Rather a zero length write merely transfers zero bytes of information to the file. A request such as SMB_COM_WRITE must be used to truncate the file. If WriteMode has bit0 set in the request and Fid refers to a disk file, the response is not sent from the server until the data is on stable storage. If Fid refers to a named pipe, it is possible that the client wishes to transfer more data to the named pipe than the negotiated client and server buffer sizes permit. In this case, the data will arrive at the server in multiple SMB_COM_WRITE_ANDX messages. If WriteMode Bit2 and Bit3 are set, this is the first SMB of the sequence, and the total number of bytes which will be written are the sum of DataLength and Remaining. Subsequent SMB_COM_WRITE_ANDX messages having WriteMode Bit2 set and possessing the same Pid and Fid will be gathered up in the server until DataLength+Remaining bytes have been received, at which time all the data is written to the named pipe in one message. The return field Remaining is valid only if Fid refers to a named pipe, and WriteMode has Bit1 set in the request. It is used to return the number of bytes currently available in the pipe. This information can then be used by the client to know when a subsequent (non blocking) read of the pipe may return some data. When the read request is actually received by the server there may be more or less actual data in the pipe (more data has been written to the pipe / device or another reader drained it). If the negotiated dialect is NT LM 0.12 or later, the Large File format of this SMB may be used to access portions of files requiring offsets expressed as 64 bits. The following are the only valid AndXCommand values for this SMB: SMB_COM_READ SMB_COM_READ_ANDX SMB_COM_LOCK_AND_READ SMB_COM_WRITE_ANDX SMB_COM_CLOSE TRANSACTIONS SMB_COM_TRANSACTION performs a symbolically named transaction. This transaction is known only by a name (no file handle used). SMB_COM_TRANSACTION2 likewise performs a transaction, but a word parameter is used to identify the transaction instead of a name. SMB_COM_NT_TRANSACTION is used for commands that potentially need to transfer a large amount of data (greater than 64K bytes). SMB_COM_TRANSACTION and SMB_COM_TRANSACTION2 Formats Primary Client Request Description Command SMB_COM_TRANSACTION or SMB_COM_TRANSACTION2 UCHAR WordCount; Count of parameter words; value = (14 + SetupCount) USHORT TotalParameterCount; Total parameter bytes being sent USHORT TotalDataCount; Total data bytes being sent USHORT MaxParameterCount; Max parameter bytes to return USHORT MaxDataCount; Max data bytes to return UCHAR MaxSetupCount; Max setup words to return UCHAR Reserved; USHORT Flags; Additional information: bit 0 - also disconnect TID in Tid bit 1 - one-way transacion (no resp) ULONG Timeout; USHORT Reserved2; USHORT ParameterCount; Parameter bytes sent this buffer USHORT ParameterOffset; Offset (from header start) to params USHORT DataCount; Data bytes sent this buffer USHORT DataOffset; Offset (from header start) to data UCHAR SetupCount; Count of setup words UCHAR Reserved3; Reserved (pad above to word) USHORT Setup[SetupCount]; Setup words (# = SetupWordCount) USHORT ByteCount; Count of data bytes STRING Name[]; Name of transaction (NULL if SMB_COM_TRANSACTION2) UCHAR Pad[]; Pad to SHORT or LONG UCHAR Parameters[ ParameterCount]; Parameter bytes (# = ParameterCount) UCHAR Pad1[]; Pad to SHORT or LONG UCHAR Data[ DataCount ]; Data bytes (# = DataCount) Interim Server Response Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 Secondary Client Request Description Command SMB_COM_TRANSACTION_SECONDARY UCHAR WordCount; Count of parameter words = 8 USHORT TotalParameterCount; Total parameter bytes being sent USHORT TotalDataCount; Total data bytes being sent USHORT ParameterCount; Parameter bytes sent this buffer USHORT ParameterOffset; Offset (from header start) to params USHORT ParameterDisplacement; Displacement of these param bytes USHORT DataCount; Data bytes sent this buffer USHORT DataOffset; Offset (from header start) to data USHORT DataDisplacement; Displacement of these data bytes USHORT Fid; Fid for handle based requests, else 0xFFFF. This field is present only if this is an SMB_COM_TRANSACTION2 request. USHORT ByteCount; Count of data bytes UCHAR Pad[]; Pad to SHORT or LONG UCHAR Parameters[ParameterCount]; Parameter bytes (# = ParameterCount) UCHAR Pad1[]; Pad to SHORT or LONG UCHAR Data[DataCount]; Data bytes (# = DataCount) Server Response Description UCHAR WordCount; Count of data bytes; value = 10 + SetupCount USHORT TotalParameterCount; Total parameter bytes being sent USHORT TotalDataCount; Total data bytes being sent USHORT Reserved; USHORT ParameterCount; Parameter bytes sent this buffer USHORT ParameterOffset; Offset (from header start) to params USHORT ParameterDisplacement; Displacement of these param bytes USHORT DataCount; Data bytes sent this buffer USHORT DataOffset; Offset (from header start) to data USHORT DataDisplacement; Displacement of these data bytes UCHAR SetupCount; Count of setup words UCHAR Reserved2; Reserved (pad above to word) USHORT Setup[SetupWordCount]; Setup words (# = SetupWordCount) USHORT ByteCount; Count of data bytes UCHAR Pad[]; Pad to SHORT or LONG UCHAR Parameters[ParameterCount]; Parameter bytes (# = ParameterCount) UCHAR Pad1[]; Pad to SHORT or LONG UCHAR Data[DataCount]; Data bytes (# = DataCount) SMB_COM_NT_TRANSACTION Formats Primary Client Request Description UCHAR WordCount; Count of parameter words; value = (19 + SetupCount) UCHAR MaxSetupCount; Max setup words to return USHORT Reserved; ULONG TotalParameterCount; Total parameter bytes being sent ULONG TotalDataCount; Total data bytes being sent ULONG MaxParameterCount; Max parameter bytes to return ULONG MaxDataCount; Max data bytes to return ULONG ParameterCount; Parameter bytes sent this buffer ULONG ParameterOffset; Offset (from header start) to params ULONG DataCount; Data bytes sent this buffer ULONG DataOffset; Offset (from header start) to data UCHAR SetupCount; Count of setup words USHORT Function; The transaction function code UCHAR Buffer[1]; USHORT Setup[SetupWordCount]; Setup words USHORT ByteCount; Count of data bytes UCHAR Pad1[]; Pad to LONG UCHAR Parameters[ParameterCount]; Parameter bytes UCHAR Pad2[]; Pad to LONG UCHAR Data[DataCount]; Data bytes Interim Server Response Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 Secondary Client Request Description UCHAR WordCount; Count of parameter words = 18 UCHAR Reserved[3]; MBZ ULONG TotalParameterCount; Total parameter bytes being sent ULONG TotalDataCount; Total data bytes being sent ULONG ParameterCount; Parameter bytes sent this buffer ULONG ParameterOffset; Offset (from header start) to params ULONG ParameterDisplacement; Specifies the offset from the start of the overall parameter block to the parameter bytes that are contained in this message ULONG DataCount; Data bytes sent this buffer ULONG DataOffset; Offset (from header start) to data ULONG DataDisplacement; Specifies the offset from the start of the overall data block to the data bytes that are contained in this message. UCHAR Reserved1; USHORT ByteCount; Count of data bytes UCHAR Pad1[]; Pad to LONG UCHAR Parameters[ParameterCount]; Parameter bytes UCHAR Pad2[]; Pad to LONG UCHAR Data[DataCount]; Data bytes Server Response Description UCHAR WordCount; Count of data bytes; value = 18 + SetupCount UCHAR Reserved[3]; ULONG TotalParameterCount; Total parameter bytes being sent ULONG TotalDataCount; Total data bytes being sent ULONG ParameterCount; Parameter bytes sent this buffer ULONG ParameterOffset; Offset (from header start) to Parameters ULONG ParameterDisplacement; Specifies the offset from the start of the overall parameter block to the parameter bytes that are contained in this message ULONG DataCount; Data bytes sent this buffer ULONG DataOffset; Offset (from header start) to data ULONG DataDisplacement; Specifies the offset from the start of the overall data block to the data bytes that are contained in this message. UCHAR SetupCount; Count of setup words USHORT Setup[SetupWordCount]; Setup words USHORT ByteCount; Count of data bytes UCHAR Pad1[]; Pad to LONG UCHAR Parameters[ParameterCount]; Parameter bytes UCHAR Pad2[]; Pad to SHORT or LONG UCHAR Data[DataCount]; Data bytes Functional Description The SMB_COM_TRANSACTION command's scope includes named pipes and mailslots. Where the resource is unidirectional (such as class 2 writes to mailslots), bit1 of Flags in the request can be set indicating that no response is needed. The other transactions accommodate IOCTL requests and file system requests which require the transfer of an extended attribute list. The transaction Setup information and/or Parameters define functions specific to a particular resource on a particular server. Therefore the functions supported are not defined by the protocol, but by client and server implementations. The transaction protocol simply provides a means of delivering them and retrieving the results. The number of bytes needed in order to perform the transaction request may be more than will fit in a single buffer. At the time of the request, the client knows the number of parameter and data bytes expected to be sent and passes this information to the server via the primary request (TotalParameterCount and TotalDataCount). This may be reduced by lowering the total number of bytes expected (TotalParameterCount and TotalDataCount) in each (if any) secondary request. When the amount of parameter bytes received (total of each ParameterCount) equals the total amount of parameter bytes expected (smallest TotalParameterCount) received, then the server has received all the parameter bytes. Likewise, when the amount of data bytes received (total of each DataCount) equals the total amount of data bytes expected (smallest TotalDataCount) received, then the server has received all the data bytes. The parameter bytes should normally be sent first followed by the data bytes. However, the server knows where each begins and ends in each buffer by the offset fields (ParameterOffset and DataOffset) and the length fields (ParameterCount and DataCount). The displacement of the bytes (relative to start of each) is also known (ParameterDisplacement and DataDisplacement). Thus the server is able to reasemble the parameter and data bytes should the individual requests be received out of sequence. If all parameter bytes and data bytes fit into a single buffer, then no interim response is expected and no secondary request is sent. The client knows the maximum amount of data bytes and parameter bytes which the server may return (from MaxParameterCount and MaxDataCount of the request). Thus the client initializes its bytes expected variables to these values. The server then informs the client of the actual amounts being returned via each message of the server response (TotalParameterCount and TotalDataCount). The server may reduce the expected bytes by lowering the total number of bytes expected (TotalParameterCount and/or TotalDataCount) in each (any) response. When the amount of parameter bytes received (total of each ParameterCount) equals the total amount of parameter bytes expected (smallest TotalParameterCount) received, then the client has received all the parameter bytes. Likewise, when the amount of data bytes received (total of each DataCount) equals the total amount of data bytes expected (smallest TotalDataCount) received, then the client has received all the data bytes. The parameter bytes should normally be returned first followed by the data bytes. However, the client knows where each begins and ends in each buffer by the offset fields (ParameterOffset and DataOffset) and the length fields (ParameterCount and DataCount). The displacement of the bytes (relative to start of each) is also known (ParameterDisplacement and DataDisplacement). The client is able to reasemble the parameter and data bytes should the server responses be received out of sequence. If a connectionless transport is being used, the transaction requests must be properly sequenced in the Connectionless.SequenceNumber SMB header field. The Mid of any secondary client requests must match the Mid of the primary client request. The server responds to each request piece except the last one with a response indicating that the server is ready for the next piece. The last piece is responded to with the first piece of the result data. The client then sends an SMB_COM_TRANSACTION_SECONDARY SMB with ParameterDisplacement set to the number of parameter bytes received so far and DataDisplacement set to the number of data bytes received so far and ParameterCount, ParameterOffset, DataCount, and DataOffset set to zero (0). The server responds with the next piece of the transaction result. The process is repeated until all of the response information has been received. When the transaction has been completed, the client must send another sequenced command (such as an SMB_COM_ECHO) to the server to allow the server to know that the final piece was received and that resources allocated to the transaction command may be released. The flow for these transactions over a connection oriented transport is: 1. The client sends the primary client request identifying the total bytes (both parameters and data) which are expected to be sent and contains the set up words and as many of the parameter and data bytes bytes as will fit in a negotiated size buffer. This request also identifies the maximum number of bytes (setup, parameters and data) the server is to return on the transaction completion. If all the bytes fit in the single buffer, skip to step 4. 2. The server responds with a single interim response meaning "ok, send the remainder of the bytes" or (if error response) terminate the transaction. 3. The client then sends another buffer full of bytes to the server. This step is repeated until all of the bytes are sent and received. 4. The Server sets up and performs the transaction with the information provided. 5. Upon completion of the transaction, the server sends back (up to) the number of parameter and data bytes requested (or as many as will fit in the negotiated buffer size). This step is repeated until all result bytes have been returned. The flow for the transaction protocol when the request parameters and data do not all fit in a single buffer is: Client Server Primary TRANSACTION request ® Interim Server Response Secondary TRANSACTION request 1 ® Secondary TRANSACTION request 2 ® Secondary TRANSACTION request N ® TRANSACTION response 1 TRANSACTION response 2 TRANSACTION response m The flow for the transaction protocol when the request parameters and data does all fit in a single buffer is: Client Server Primary TRANSACTION request ® TRANSACTION response 1 TRANSACTION response 2 TRANSACTION response m The flow for the transaction protocol over a connectionless transport is: 1. The client sends the primary client request identifying the total bytes (both parameters and data) which are expected to be sent and contains the set up words and as many of the parameter and data bytes bytes as will fit in a negotiated size buffer. This request also identifies the maximum number of bytes (setup, parameters and data) the server is to return on completion. If all the bytes fit in the single buffer, skip to step 4. 2. The server responds with a single interim response meaning "ok, send the remainder of the bytes" or (if error response) terminate the transaction. 3. The client then sends another buffer full of bytes to the server. The server responds with an interim server response. This step is repeated until all of the bytes are sent and received. 4. The Server sets up and performs the transaction with the information provided. 5. Upon completion of the transaction, the server sends back (up to) the number of parameter and data bytes requested (or as many as will fit in the negotiated buffer size). 6. The client responds with a transaction secondary request. The server sends back more response data. This step is repeated until all result bytes have been returned. 7. The client sends a sequenced request to the server such as SMB_COM_ECHO The primary transaction request through the final response make up the complete transaction exchange, thus the Tid, Pid, Uid and Mid must remain constant and can be used as appropriate by both the server and the client. Of course, other SMB requests may intervene as well. SMB_COM_TRANSACTION Operations Mail Slot Transaction Protocol The only transaction allowed to a mailslot is a mailslot write. The following table shows the interpretation of parameters for a mailslot transaction: Name Value Description Command SMB_COM_TRANSACTION Name \MAILSLOT\ STRING Name of mail slot to write SetupCount 3 Setup[0] 1 Command code == write mailslot Setup[1] Ignored Setup[2] Ignored TotalDataCount n Size of data to write to the mailslot Data[ n ] The data to write to the mailslot Named Pipe Transaction Protocol A named pipe SMB_COM_TRANSACTION is used to wait for the specified named pipe to become available (WaitNmPipe) or perform a logical "open ® write ® read ® close" of the pipe (CallNmPipe), along with other functions defined below. The identifier "\PIPE\" denotes a named pipe transaction, where the is the pipe name to apply the transaction against. Name Value Description Command SMB_COM_TRANSACTION Name \PIPE\ Name of pipe for operation SetupCount 2 Setup[0] See Below Subcommand code Setup[1] Fid of pipe If required TotalDataCount n Size of data Data[ n ] If required The subcommand codes, placed in Setup[0], for named pipe operations are: SubCommand Code Value Description CallNamedPipe 0x54 open/write/read/close pipe WaitNamedPipe 0x53 wait for pipe to be nonbusy PeekNmPipe 0x23 read but don't remove data QNmPHandState 0x21 query pipe handle modes SetNmPHandState 0x01 set pipe handle modes QNmPipeInfo 0x22 query pipe attributes TransactNmPipe 0x26 write/read operation on pipe RawReadNmPipe 0x11 read pipe in "raw" (non message mode) RawWriteNmPipe 0x31 write pipe "raw" (non message mode) */ CallNamedPipe This command is used to implement the Win32 CallNamedPipe() API remotely. The CallNamedPipe function connects to a message-type pipe (and waits if an instance of the pipe is not available), writes to and reads from the pipe, and then closes the pipe. This form of the transaction protocol sends no parameter bytes, thus the bytes to be written to the pipe are sent as data bytes and the bytes read from the pipe are returned as data bytes. The number of bytes being written is defined by TotalDataCount and the max number of bytes to return is defined by MaxDataCount. On the response TotalParameterCount is 0 (no param bytes to return), TotalDataCount indicates the amount of databytes being returned in total and DataCount identifies the amount of data being retuned in each buffer. Note that the full form of the Transaction protocol can be used to write and read up to 65,535 bytes each utilizing the secondary requests and responses. WaitNamedPipe The command is used to implement the Win32 WaitNamedPipe() API remotely. The WaitNamedPipe function waits until either a time-out interval elapses or an instance of the specified named pipe is available to be connected to (that is, the pipe's server process has a pending ConnectNamedPipe operation on the pipe). The server will wait up to Timeout milliseconds for a pipe of the name given to become available. Note that although the timeout is specified in milliseconds, by the time that the timeout occurs and the client receives the timed out response much more time than specified may have occurred. This form of the transaction protocol sends no data or parameter bytes. The response also contains no data or parameters. If the transaction response indicates success, the pipe may now be available. However, this request does not reserve the pipe, thus all waiting programs may race to get the pipe now available. The losers will get an error on the pipe open attempt. PeekNamedPipe This form of the pipe Transaction protocol is used to implement the Win32 PeekNamePipe() API remotely. The PeekNamedPipe function copies data from a named or anonymous pipe into a buffer without removing it from the pipe. It also returns information about data in the pipe. TotalParameterCount and TotalDataCount should be 0 for this request. The Fid of the pipe to which this request should be applied is in Setup[1]. MaxParameterCount should be set to 6, requesting 3 words of information about the pipe, and MaxDataCount should be set to the number of bytes to “peek”. The response contains the following Parameter words: Name Description Parameters[0, 1] Total number of bytes available to be read from the pipe Parameters[2,3] Total number of bytes remaining in the message at the “head” of the pipe Parameters[4,5] Pipe status. 1 Disconnected by server 2 Listening 3 Connection to server is OK 4 Server end of pipe is closed The Data portion of the response is the data peeked from the named pipe. GetNamedPipeHandleState This form of the pipe transaction protocol is used to implement the Win32 GetNamedPipeHandleState() API. The GetNamedPipeHandleState function retrieves information about a specified named pipe. The information returned can vary during the lifetime of an instance of the named pipe. This request sends no parameters and no data. The Fid of the pipe to which this request should be applied is in Setup[1]. MaxParameterCount should be set to 2 (requesting the 1 word of information about the pipe) and MaxDataCount should be 0 (not reading the pipe). The response returns one parameter of pipe state information interpreted as: Pipe Handle State Bits 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 B E * * T T R R |--- Icount --| where: B - Blocking - 0 => reads/writes block if no data available 1 => reads/writes return immediately if no data E - Endpoint - 0 => consumer end of pipe 1 => server end of pipe TT - Type of pipe - 00 => pipe is a byte stream pipe 01 => pipe is a message pipe RR - Read Mode - 00 => Read pipe as a byte stream 01 => Read messages from pipe Icount - 8-bit count to control pipe instancing The E (endpoint) bit is 0 because this handle is the client end of a pipe. SetNamedPipeHandleState This form of the pipe transaction protocol is used to implement the Win32 SetNamedPipeHandleState() API. The SetNamedPipeHandleState function sets the read mode and the blocking mode of the specified named pipe. This request sends 1 parameter word (TotalParameterCount = 2) which is the pipe state to be set. The Fid of the pipe to which this request should be applied is in Setup[1]. The response contains no data or parameters. The interpretation of the input parameter word is: Pipe Handle State Bits 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 B * * * * * R R 0 0 0 0 0 0 0 0 where: B - Blocking - 0 => reads/writes block if no data available 1 => reads/writes return immediately if no data RR - Read Mode - 00 => Read pipe as a byte stream 01 => Read messages from pipe Note that only the read mode (byte or message) and blocking/nonblocking mode of a named pipe can be changed. Some combinations of parameters may be illegal and will be rejected as an error. GetNamedPipeInfo This form of the pipe transaction protocol is used to implement the Win32 GetNamedPipeInfo() API. The GetNamedPipeInfo function retrieves information about the specified named pipe. The request sends 1 parameter word (TotalParameterCount = 2) which is the information level requested and must be set to 1. The Fid of the pipe to which this request should be applied is in Setup[1]. MaxDataCount should be set to the size of the buffer specified by the user in which to receive the pipe information. Pipe information is returned in the data area of the response, up to the number of bytes specified. The information is returned in the following format: Name Size Description OutputBufferSize USHORT actual size of buffer for outgoing (server) I/O InputBufferSize USHORT actual size of buffer for incoming (client) I/O MaximumInstances UCHAR Maximum allowed number of instances CurrentInstances UCHAR Current number of instances PipeNameLength UCHAR Length of pipe name (including the null) PipeName STRING Name of pipe (NOT including \\NodeName - \\NodeName is prepended to this string by the client before passing back to the user) TransactNamedPipe This form of the pipe transaction protocol is used to implement the Win32 TransactNamedPipe() API. The TransactNamedPipe function combines into a single network operation the functions that write a message to and read a message from the specified named pipe. It provides an optimum way to implement transaction-oriented dialogs. TransactNamedPipe will fail if the pipe currently contains any unread data or is not in message read mode. Otherwise the call will write the entire request data bytes to the pipe and then read a response from the pipe and return it in the data bytes area of the response protocol. In the transaction request, Setup[1] must contain the Fid of the pipe. If Name is \PIPE\LANMAN, this is a server API request. The request encoding is: Request Field Description Parameters[0®1] API # Parameters[2®N] ASCIIZ RAP description of input structure Parameters[N®X] The input structure The response is formatted as: Response Field Description Parameters[0®1] Result Status Parameters[2®3] Offset to result structure The state of blocking/nonblocking has no effect on this protocol (TransactNamedPipe does not return until a message has been read into the response protocol). If MaxDataCount is too small to contain the response message, an error is returned. RawReadNamedPipe RawReadNamedPipe reads bytes directly from a pipe, regardless of whether it is a message or byte pipe. For a byte pipe, this is exactly like SMB_COM_READ. For a message pipe, this is exactly like reading the pipe in byte read mode, except message headers will also be returned in the buffer (note that message headers will always be returned in toto--never split at a byte boundary). This request sends no parameters or data to the server, and Setup[1] must contain the Fid of the pipe to read. MaxDataCount should contain the number of bytes to read raw. The response will return 0 parameters, and DataCount will be set to the number of bytes read. RawWriteNamedPipe RawWriteNamedPipe puts bytes directly into a pipe, regardless of whether it is a message or byte pipe. The data will include message headers if it is a message pipe. This call ignores the blocking/nonblocking state and always acts in a blocking manner. It returns only after all bytes have been written. The request sends no parameters. Setup[1] must contain the Fid of the pipe to write. TotalDataCount is the total amount of data to write to the pipe. Writing zero bytes to a pipe is an error unless the pipe is in message mode. The response contains no data and one parameter word. If no error is returned, the one parameter word indicates the number of the requested bytes that have been "written raw" to the specified pipe. SMB_COM_TRANSACTION2 Operations The subcommand code for SMB_COM_TRANSACTION2 request is placed in Setup[0]. The parameters associated with any particular request are placed in the Parameters vector of the request. The defined subcommand codes are: Setup[0] Transaction2 Subcommand Code Value Description TRANS2_OPEN2 0x00 Create file with extended attributes TRANS2_FIND_FIRST2 0x01 Begin search for files TRANS2_FIND_NEXT2 0x02 Resume search for files TRANS2_QUERY_FS_INFORMATION 0x03 Get file system information 0x04 Reserved TRANS2_QUERY_PATH_INFORMATION 0x05 Get information about a named file or directory TRANS2_SET_PATH_INFORMATION 0x06 Set information about a named file or directory TRANS2_QUERY_FILE_INFORMATION 0x07 Get information about a handle TRANS2_SET_FILE_INFORMATION 0x08 Set information by handle TRANS2_FSCTL 0x09 Not implemented by NT server TRANS2_IOCTL2 0x0A Not implemented by NT server TRANS2_FIND_NOTIFY_FIRST 0x0B Not implemented by NT server TRANS2_FIND_NOTIFY_NEXT 0x0C Not implemented by NT server TRANS2_CREATE_DIRECTORY 0x0D Create directory with extended attributes TRANS2_SESSION_SETUP 0x0E Session setup with extended security information TRANS2_OPEN2 This transaction is used to open or create a file having extended attributes. Client Request Value WordCount 15 TotalDataCount Total size of extended attribute list DataOffset Offset to extended attribute list in this request SetupCount 1 Setup[0] TRANS2_OPEN2 Parameter Block Encoding Description USHORT Flags; Additional information: bit set- 0 - return additional info 1 - exclusive oplock requested 2 - batch oplock requested 3 - return total length of EAs USHORT DesiredAccess; Requested file access USHORT Reserved1; Ought to be zero. Ignored by the server. USHORT FileAttributes; Attributes for file if create SMB_TIME CreationTime; Creation time to apply to file if create SMB_DATE CreationDate; Creation date to apply to file if create USHORT OpenFunction; Open function ULONG AllocationSize; Bytes to reserve on create or truncate USHORT Reserved [5]; Must be zero STRING FileName; Name of file to open or create UCHAR Data[ TotalDataCount ] FEAList structure for file to be created If secondary requests are required, they must contain 0 parameter bytes, and the Fid in the secondary request is 0xFFFF. DesiredAccess is encoded as described in the Access Mode Encoding section elsewhere in this document. FileAttributes are encoded as described in the File Attribute Encoding section elsewhere in this document. OpenFunction specifies the action to be taken depending on whether or not the file exists. This word has the following format: bits: 1111 11 5432 1098 7654 3210 rrrr rrrr rrrC rrOO where: C - Create (action to be taken if file does not exist). 0 -- Fail. 1 -- Create file. r - reserved (must be zero). O - Open (action to be taken if file exists). 0 - Fail. 1 - Open file. 2 - Truncate file. Action in the response specifies the action as a result of this request. It has the following format: bits: 1111 11 5432 1098 7654 3210 Lrrr rrrr rrrr rrOO where: L - Lock (single user total file lock status). 0 -- file opened by another user (or mode not supported by server). 1 -- file is opened only by this user at the present time. r - reserved (must be zero). O - Open (action taken on Open). 1 - The file existed and was opened. 2 - The file did not exist but was created. 3 - The file existed and was truncated. Response Parameter Block Description USHORT Fid; File handle USHORT FileAttributes; Attributes of file SMB_TIME CreationTime; Last modification time SMB_DATE CreationDate; Last modification date ULONG DataSize; Current file size USHORT GrantedAccess; Access permissions actually allowed USHORT FileType; Type fo file USHORT DeviceState; State of IPC device (e.g. pipe) USHORT Action; Action taken ULONG Reserved; USHORT EaErrorOffset; Offset into EA list if EA error ULONG EaLength; Total EA length for opened file FileType returns the kind of resource actually opened: Name Value Description FileTypeDisk 0 Disk file or directory as defined in the attribute field FileTypeByteModePipe 1 Named pipe in byte mode FileTypeMessageModePipe 2 Named pipe in message mode FileTypePrinter 3 Spooled printer FileTypeUnknown 0xFFFF Unrecognized resource type DeviceState is applicable only if the FileType is FileTypeByteModePipe or FileTypeMessageModePipe and is encoded as follows: 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 B E * * T T R R where: B - Blocking - 0 => reads/writes block if no data available 1 => reads/writes return immediately if no data E - Endpoint - 0 => consumer end of pipe 1 => server end of pipe TT - Type of pipe - 00 => pipe is a byte stream pipe 01 => pipe is a message pipe RR - Read Mode - 00 => Read pipe as a byte stream 01 => Read messages from pipe If an error was detected in the incomming EA list, the offset of the error is returned in EaErrorOffset. If bit0 of Flags in the request is clear, the FileAttributes, CreationTime, CreationDate, DataSize, GrantedAccess, FileType, and DeviceState have indeterminate values in the response. Similarly, if bit3 of the request is clear, EaLength in the response has an indeterminate value in the response. This SMB can request an oplock on the opened file. Oplocks are fully described in the Oplocks section elsewhere in this document, and there is also discussion of oplocks in the SMB_COM_LOCKING_ANDX SMB description. Bit1 and bit2 of the Flags field are used to request oplocks during open. TRANS2_FIND_FIRST2 Client Request Value WordCount 15 TotalDataCount Total size of extended attribute list SetupCount 1 Setup[0] TRANS2_FIND_FIRST2 Parameter Block Encoding Description USHORT SearchAttributes; USHORT SearchCount; Maximum number of entries to return USHORT Flags; Additional information: Bit 0 - close search after this request Bit 1 - close search if end of search reached Bit 2 - return resume keys for each entry found Bit 3 - continue search from previous ending place Bit 4 - find with backup intent USHORT InformationLevel; ULONG SearchStorageType; STRING FileName; Pattern for the search UCHAR Data[ TotalDataCount ] FEAList if InformationLevel is QUERY_EAS_FROM_LIST Response Parameter Block Description USHORT Sid; Search handle USHORT SearchCount; Number of entries returned USHORT EndOfSearch; Was last entry returned? USHORT EaErrorOffset; Offset into EA list if EA error USHORT LastNameOffset; Offset into data to file name of last entry, if server needs it to resume search; else 0 UCHAR Data[ TotalDataCount ] Level dependent info about the matches found in the search This request allows the client to search for the file(s) which match the file specification. The search can be continued if necessary with TRANS2_FIND_NEXT2. There are numerous levels of information which may be obtained for the returned files, the desired level is specified in the InformationLevel field of the request. InformationLevel Name Value SMB_INFO_STANDARD 1 SMB_INFO_QUERY_EA_SIZE 2 SMB_INFO_QUERY_EAS_FROM_LIST 3 SMB_FIND_FILE_DIRECTORY_INFO 0x101 SMB_FIND_FILE_FULL_DIRECTORY_INFO 0x102 SMB_FIND_FILE_NAMES_INFO 0x103 SMB_FIND_FILE_BOTH_DIRECTORY_INFO 0x104 Information levels whose values are greater than 0x101 are mapped to corresponding calls to NtQueryInformationFile calls by the server. The three levels below 0x101 are described below. The requested information is placed in the Data portion of the transaction response. A client which does not support long names can only request SMB_INFO_STANDARD. The following sections detail the data returned for each InformationLevel. SMB_INFO_STANDARD Response Field Description SMB_DATE CreationDate; Date when file was created SMB_TIME CreationTime; Time when file was created SMB_DATE LastAccessDate; Date of last file access SMB_TIME LastAccessTime; Time of last file access SMB_DATE LastWriteDate; Date of last write to the file SMB_TIME LastWriteTime; Time of last write to the file ULONG DataSize; File Size ULONG AllocationSize; Size of filesystem allocation unit USHORT Attributes; File Attributes UCHAR FileNameLength; Length of filename in bytes STRING FileName; Name of found file SMB_INFO_QUERY_EA_SIZE Response Field Description SMB_DATE CreationDate; Date when file was created SMB_TIME CreationTime; Time when file was created SMB_DATE LastAccessDate; Date of last file access SMB_TIME LastAccessTime; Time of last file access SMB_DATE LastWriteDate; Date of last write to the file SMB_TIME LastWriteTime; Time of last write to the file ULONG DataSize; File Size ULONG AllocationSize; Size of filesystem allocation unit USHORT Attributes; File Attributes ULONG EaSize; Size of file’s EA information UCHAR FileNameLength; Length of filename in bytes STRING FileName; Name of found file SMB_INFO_QUERY_EAS_FROM_LIST This request returns the same information as SMB_INFO_QUERY_EA_SIZE, but only for files which have an EA list which match the EA information in the Data part of the request. SMB_FIND_FILE_DIRECTORY_INFO Response Field Description ULONG NextEntryOffset; Offset from this structure to beginning of next one ULONG FileIndex; LARGE_INTEGER CreationTime; file creation time LARGE_INTEGER LastAccessTime; last access time LARGE_INTEGER LastWriteTime; last write time LARGE_INTEGER ChangeTime; last attribute change time LARGE_INTEGER EndOfFile; file size LARGE_INTEGER AllocationSize; size of filesystem allocation information ULONG FileAttributes; NT style encoding of file attributes ULONG FileNameLength; Length of filename in bytes STRING FileName; Name of the file SMB_FIND_FILE_FULL_DIRECTORY_INFO Response Field Description ULONG NextEntryOffset; Offset from this structure to beginning of next one ULONG FileIndex; LARGE_INTEGER CreationTime; file creation time LARGE_INTEGER LastAccessTime; last access time LARGE_INTEGER LastWriteTime; last write time LARGE_INTEGER ChangeTime; last attribute change time LARGE_INTEGER EndOfFile; file size LARGE_INTEGER AllocationSize; size of filesystem allocation information ULONG FileAttributes; NT style encoding of file attributes ULONG FileNameLength; Length of filename in bytes ULONG EaSize; Size of file’s extended attributes STRING FileName; Name of the file SMB_FIND_FILE_BOTH_DIRECTORY_INFO Response Field Description ULONG NextEntryOffset; Offset from this structure to beginning of next one ULONG FileIndex; LARGE_INTEGER CreationTime; file creation time LARGE_INTEGER LastAccessTime; last access time LARGE_INTEGER LastWriteTime; last write time LARGE_INTEGER ChangeTime; last attribute change time LARGE_INTEGER EndOfFile; file size LARGE_INTEGER AllocationSize; size of filesystem allocation information ULONG FileAttributes; NT style encoding of file attributes ULONG FileNameLength; Length of FileName in bytes ULONG EaSize; Size of file’s extended attributes UCHAR ShortNameLength; Length of file’s short name in bytes WCHAR ShortName[12]; File’s 8.3 conformant name in Unicode STRING FileName; Files full length name SMB_FIND_FILE_NAMES_INFO Response Field Description ULONG NextEntryOffset; Offset from this structure to beginning of next one ULONG FileIndex; ULONG FileNameLength; Length of FileName in bytes STRING FileName; Files full length name TRANS2_FIND_NEXT2 This request resumes a search which was begun with a previous TRANS2_FIND_FIRST2 request. Client Request Value WordCount 15 SetupCount 1 Setup[0] TRANS2_FIND_NEXT2 Parameter Block Encoding Description USHORT Sid; Search handle USHORT SearchCount; Maximum number of entries to return USHORT InformationLevel; Levels described in TRANS2_FIND_FIRST2 request ULONG ResumeKey; Value returned by previous find2 call USHORT Flags; Additional information: bit set- 0 - close search after this request 1 - close search if end of search reached 2 - return resume keys for each entry found 3 - resume/continue from previous ending place 4 - find with backup intent STRING FileName; Resume file name Sid is the value returned by a previous successful TRANS2_FIND_FIRST2 call. If Bit3 of Flags is set, then FileName may be the NULL string, since the search is continued from the previous TRANS2_FIND request. Otherwise, FileName must not be more than 256 characters long. Response Parameter Block Description USHORT SearchCount; Number of entries returned USHORT EndOfSearch; Was last entry returned? USHORT EaErrorOffset; Offset into EA list if EA error USHORT LastNameOffset; Offset into data to file name of last entry, if server needs it to resume search; else 0 UCHAR Data[TotalDataCount] Level dependent info about the matches found in the search TRANS2_QUERY_FS_INFORMATION This transaction requests information about a filesystem on the server. Client Request Value WordCount; 15 TotalParameterCount; 2 or 4 MaxSetupCount; 0 SetupCount; 1 or 2 Setup[0]; TRANS2_QUERY_FS_INFORMATION Parameter Block Encoding Description USHORT Information Level; Level of information requested If the transaction request is TRANS2_QUERY_FS_INFORMATION, the filesystem is identified by Tid in the SMB header. MaxDataCount in the transaction request must be large enough to accommodate the response. The encoding of the response parameter block depends on the InformationLevel requested. Information levels whose values are greater than 0x102 are mapped to corresponding calls to NtQueryVolumeInformatinFile calls by the server. The two levels below 0x102 are described below. The requested information is placed in the Data portion of the transaction response. InformationLevel Value NtQueryVolumeInformationFile equivalent SMB_INFO_ALLOCATION 1 SMB_INFO_VOLUME 2 SMB_QUERY_FS_VOLUME_INFO 0x102 FileFsVolumeInformation SMB_QUERY_FS_SIZE_INFO 0x103 FileFsSizeInformation SMB_QUERY_FS_DEVICE_INFO 0x104 FileFsDeviceInformation SMB_QUERY_FS_ATTRIBUTE_INFO 0x105 FileFsAttributeInformation The following sections describe the InformationLevel dependent encoding of the data part of the transaction response for the non-NT-equivalent information levels. SMB_INFO_ALLOCATION Data Block Encoding Description ULONG idFileSystem; File system identifier. NT server always returns 0 ULONG cSectorUnit; Number of sectors per allocation unit ULONG cUnit; Total number of allocation units ULONG cUnitAvail; Total number of available allocation units USHORT cbSector; Number of bytes per sector SMB_INFO_VOLUME Data Block Encoding Description ULONG ulVsn; Volume serial number UCHAR cch; Number of characters in Label STRING Label; The volume label TRANS2_QUERY_PATH_INFORMATION This request is used to get information about a specific file or subdirectory. Client Request Value WordCount 15 MaxSetupCount 0 SetupCount 1 Setup[0] TRANS2_QUERY_PATH_INFORMATION Parameter Block Encoding Description USHORT InformationLevel; Level of information requested ULONG Reserved; Must be zero STRING FileName; File or directory name The following InformationLevels may be requested: Information Level Value NtQueryInformationFile Equivalent SMB_INFO_STANDARD 1 SMB_INFO_QUERY_EA_SIZE 2 SMB_INFO_QUERY_EAS_FROM_LIST 3 SMB_INFO_QUERY_ALL_EAS 4 SMB_INFO_IS_NAME_VALID 6 SMB_QUERY_FILE_BASIC_INFO 0x101 FileBasicInformation SMB_QUERY_FILE_STANDARD_INFO 0x102 FileStandardInformation SMB_QUERY_FILE_EA_INFO 0x103 FileEaInformation SMB_QUERY_FILE_NAME_INFO 0x104 FileNameInformation SMB_QUERY_FILE_ALL_INFO 0x107 FileAllInformation SMB_QUERY_FILE_ALT_NAME_INFO 0x108 FileAlternateNameInformation SMB_QUERY_FILE_STREAM_INFO 0x109 FileStreamInformation SMB_QUERY_FILE_COMPRESSION_INFO 0x10B FileCompressionInformation Information levels whose values are greater than 0x101 are mapped to corresponding calls to NtQueryInformationFile calls by the server. The five levels below 0x101 are described below. The requested information is placed in the Data portion of the transaction response. For the NT equivalent responses, the transaction response has 1 parameter word which should be ignored by the client. SMB_INFO_STANDARD & SMB_INFO_QUERY_EA_SIZE Data Block Encoding Description SMB_DATE CreationDate; Date when file was created SMB_TIME CreationTime; Time when file was created SMB_DATE LastAccessDate; Date of last file access SMB_TIME LastAccessTime; Time of last file access SMB_DATE LastWriteDate; Date of last write to the file SMB_TIME LastWriteTime; Time of last write to the file ULONG DataSize; File Size ULONG AllocationSize; Size of filesystem allocation unit USHORT Attributes; File Attributes ULONG EaSize; Size of file’s EA information (SMB_INFO_QUERY_EA_SIZE) SMB_INFO_QUERY_EAS_FROM_LIST & SMB_INFO_QUERY_ALL_EAS Response Field Value MaxDataCount Length of FEAlist found (minimum value is 4) Parameter Block Encoding Description USHORT EaErrorOffset Offset into EAList of EA error Data Block Encoding Description ULONG ListLength; Length of the remaining data UCHAR EaList[] The extended attributes list SMB_INFO_IS_NAME_VALID This requests checks to see if the name of the file contained in the request’s Data field has a valid path syntax. No parameters or data are returned on this information request. An error is returned if the syntax of the name is incorrect. Success indicates the server accepts the path syntax, but it does not ensure the file or directory actually exists. TRANS2_SET_PATH_INFORMATION This request is used to set information about a specific file or subdirectory. Client Request Value WordCount 15 MaxSetupCount 0 SetupCount 1 Setup[0] TRANS2_SET_PATH_INFORMATION Parameter Block Encoding Description USHORT InformationLevel; Level of information to set ULONG Reserved; Must be zero STRING FileName; File or directory name The following InformationLevels may be set: Information Level Value SMB_INFO_STANDARD 1 SMB_INFO_QUERY_EA_SIZE 2 SMB_INFO_QUERY_ALL_EAS 4 The response formats are: SMB_INFO_STANDARD & SMB_INFO_QUERY_EA_SIZE Parameter Block Encoding Description USHORT Reserved 0 Data Block Encoding Description SMB_DATE CreationDate; Date when file was created SMB_TIME CreationTime; Time when file was created SMB_DATE LastAccessDate; Date of last file access SMB_TIME LastAccessTime; Time of last file access SMB_DATE LastWriteDate; Date of last write to the file SMB_TIME LastWriteTime; Time of last write to the file ULONG DataSize; File Size ULONG AllocationSize; Size of filesystem allocation unit USHORT Attributes; File Attributes ULONG EaSize; Size of file’s EA information (SMB_INFO_QUERY_EA_SIZE) SMB_INFO_QUERY_ALL_EAS Response Field Value MaxDataCount Length of FEAlist found (minimum value is 4) Parameter Block Encoding Description USHORT EaErrorOffset Offset into EAList of EA error Data Block Encoding Description ULONG ListLength; Length of the remaining data UCHAR EaList[] The extended attributes list TRANS2_QUERY_FILE_INFORMATION This request is used to get information about a specific file or subdirectory given a handle to it. Client Request Value WordCount 15 MaxSetupCount 0 SetupCount 1 Setup[0] TRANS2_QUERY_FILE_INFORMATION Parameter Block Encoding Description USHORT Fid; Handle of file for request USHORT InformationLevel; Level of information requested The avaliable information levels, as well as the format of the response are identical to TRANS2_QUERY_PATH_INFORMATION. TRANS2_SET_FILE_INFORMATION This request is used to set information about a specific file or subdirectory given a handle to the file or subdirectory. Client Request Value WordCount 15 MaxSetupCount 0 SetupCount 1 Setup[0] TRANS2_SET_FILE_INFORMATION Parameter Block Encoding Description USHORT Fid; Handle of file for request USHORT InformationLevel; Level of information requested USHORT Reserved; Ignored by the server The following InformationLevels may be set: Information Level Value NtSetFileInformation equiv SMB_INFO_STANDARD 1 SMB_INFO_QUERY_EA_SIZE 2 SMB_SET_FILE_BASIC_INFO 0x101 FileBasicInformation SMB_SET_FILE_DISPOSITION_INFO 0x102 FileDispositionInformation SMB_SET_FILE_ALLOCATION_INFO 0x103 FileAllocationInformation SMB_SET_FILE_END_OF_FILE_INFO 0x104 FileEndOfFileInformation Information levels whose values are greater than 0x100 are mapped to corresponding calls to NtSetInformationFile calls by the server. The two levels below 0x100 are as described in the NT_SET_PATH_INFORMATION transaction. The requested information is placed in the Data portion of the transaction response. For the NT equivalent responses, the transaction response has 1 parameter word which should be ignored by the client. TRANS2_CREATE_DIRECTORY This requests the server to create a directory relative to Tid in the SMB header, optionally assigning extended attributes to it. Client Request Value WordCount 15 MaxSetupCount 0 SetupCount 1 Setup[0] TRANS2_CREATE_DIRECTORY Parameter Block Encoding Description ULONG Reserved; Reserved--must be zero STRING Name[]; Directory name to create UCHAR Data[]; Optional FEAList for the new directory Response Parameter Block Description USHORT EaErrorOffset Offset into FEAList of first error which occurred while setting EAs SMB_COM_NT_TRANSACTION Operations For these transactions, Function in the primary client request indicates the operation to be performed. It may assume one of the following values: SubCommand Code Value Description NT_TRANSACT_CREATE 1 File open/create NT_TRANSACT_IOCTL 2 Device IOCTL NT_TRANSACT_SET_SECURITY_DESC 3 Set security descriptor NT_TRANSACT_NOTIFY_CHANGE 4 Start directory watch NT_TRANSACT_RENAME 5 Reserved (Handle-based rename) NT_TRANSACT_QUERY_SECURITY_DESC 6 Retrieve security descriptor info The following sections describe these requests. NT_TRANSACT_CREATE This command is used to create or open a file or a directory, when EAs or an SD must be applied to the file. Request Parameter Block Encoding Description ULONG Flags; Creation flags (see below) ULONG RootDirectoryFid; Optional directory for relative open ACCESS_MASK DesiredAccess; Desired access (NT format) LARGE_INTEGER AllocationSize; The initial allocation size in bytes, if file created ULONG FileAttributes; The file attributes, (NT format) ULONG ShareAccess; The share access (NT format) ULONG CreateDisposition; Action to take if file exists or not (NT format) ULONG CreateOptions; Options for creating a new file (NT format) ULONG SecurityDescriptorLength; Length of SD in bytes ULONG EaLength; Length of EA in bytes ULONG NameLength; Length of name in characters ULONG ImpersonationLevel; Security QOS information (NT format) UCHAR SecurityFlags; Security QOS information (NT format) STRING Name[NameLength]; The name of the file (not NULL terminated) Data Block Encoding Description UCHAR SecurityDescriptor[ SecurityDescriptorLength]; UCHAR ExtendedAttributes[ EaLength ]; Creation Flag Name Value Description NT_CREATE_REQUEST_OPLOCK 0x02 Level I oplock requested NT_CREATE_REQUEST_OPBATCH 0x04 Batch oplock requested NT_CREATE_OPEN_TARGET_DIR 0x08 Target for open is a directory Output Parameter Block Encoding Description UCHAR OplockLevel; The oplock level granted 0 - No oplock granted 1 - Exclusive oplock granted 2 - Batch oplock granted 3 - Level II oplock granted UCHAR Reserved; USHORT Fid; The file ID ULONG CreateAction; The action taken ULONG EaErrorOffset; Offset of the EA error TIME CreationTime; The time the file was created TIME LastAccessTime; The time the file was accessed TIME LastWriteTime; The time the file was last written TIME ChangeTime; The time the file was last changed ULONG FileAttributes; The file attributes LARGE_INTEGER AllocationSize; The number of byes allocated LARGE_INTEGER EndOfFile; The end of file offset USHORT FileType; USHORT DeviceState; state of IPC device (e.g. pipe) BOOLEAN Directory; TRUE if this is a directory The above parameters are in native NT format. NT_TRANSACT_IOCTL This command allows device and file system control functions to be transferred transparently from client to server. Setup Words Encoding Description ULONG FunctionCode; NT device or file system control code USHORT Fid; Handle for io or fs control. Unless bit0 of IsFlags is set. BOOLEAN IsFsctl; Indicates whether the command is a device control (FALSE) or a file system control (TRUE). UCHAR IsFlags; bit0 - command is to be applied to share root handle. Share must be a DFS share. Data Block Encoding Description Data[ TotalDataCount ] Passed to the Fsctl or Ioctl Server Response Description SetupCount 1 Setup[0] Length of information returned by io or fs control DataCount Length of information returned by io or fs control Data[ DataCount ] The results of the io or fs control NT_TRANSACT_SET_SECURITY_DESC This command allows the client to change the security descriptor on a file. Client Parameter Block Encoding Description USHORT Fid; FID of target USHORT Reserved; MBZ ULONG SecurityInformation; Fields of SD that to set Data Block Encoding Description Data[TotalDataCount] Security Descriptor information Data is passed directly to NtSetSecurityObject(), with SecurityInformation describing which information to set. The transaction response contains no parameters or data. NT_TRANSACT_NOTIFY_CHANGE Client Setup Words Description ULONG CompletionFilter; Specifies operation to monitor (NT format) USHORT Fid; Fid of directory to monitor BOOLEAN WatchTree; TRUE = watch all subdirectories too UCHAR Reserved; MBZ This command notifies the client when the directory specified by Fid is modified. It also returns the name(s) of the file(s) that changed. The command completes once the directory has been modified based on the supplied CompletionFilter. The command is a "single shot" and therefore needs to be reissued to watch for more directory changes. A directory file must be opened before this command may be used. Once the directory is open, this command may be used to begin watching files and subdirectories in the specified directory for changes. The first time the command is issued, the MaxParameterCount field in the transact header determines the size of the buffer that will be used at the server to buffer directory change information between issuances of the notify change commands. When a change that is in the CompletionFilter is made to the directory, the command completes. The names of the files that have changed since the last time the command was issued are returned to the client. The ParameterCount field of the response indicates the number of bytes that are being returned. If too many files have changed since the last time the command was issued, then zero bytes are returned and an alternate status code is returned in the Status field of the response. Server Response Description ParameterCount # of bytes of change data Parameters[ ParameterCount ] FILE_NOTIFY_INFORMATION structures The response contains FILE_NOTIFY_INFORMATION structures, as defined in ntioapi.h. The NextEntryOffset field of the structure specifies the offset, in bytes, from the start of the current entry to the next entry in the list. If this is the last entry in the list, this field is zero. Each entry in the list must be longword aligned, so NextEntryOffset must be a multiple of four. NT_TRANSACT_QUERY_SECURITY_DESC This command allows the client to retrieve the security descriptor on a file. Client Parameter Block Description USHORT Fid; FID of target USHORT Reserved; MBZ ULONG SecurityInformation; Fields of descriptor to set NtQuerySecurityObject() is called, requesting SecurityInformation. The result of the call is returned to the client in the Data part of the transaction response. NT_CANCEL: Cancel request This SMB allows a client to cancel a request currently pending at the server. Client Request Description UCHAR WordCount; No words are sent (== 0) USHORT ByteCount; No bytes (==0) The Sid, Uid, Pid, Tid, and Mid fields of the SMB are used to locate an pending server request from this session. If a pending request is found, it is “hurried along” which may result in success or failure of the original request. No other response is generated for this SMB. FIND_CLOSE2: Close Search This SMB closes a search started by the TRANS2_FIND_FIRST2 transaction request. Client Request Description UCHAR WordCount; Count of parameter words = 1 USHORT Sid; Find handle USHORT ByteCount; Count of data bytes = 0 Server Response Description UCHAR WordCount; Count of parameter words = 0 USHORT ByteCount; Count of data bytes = 0 SMB Command Codes The following values have been assigned for the SMB Commands. SMB_COM_CREATE_DIRECTORY 0x00 SMB_COM_DELETE_DIRECTORY 0x01 SMB_COM_OPEN 0x02 SMB_COM_CREATE 0x03 SMB_COM_CLOSE 0x04 SMB_COM_FLUSH 0x05 SMB_COM_DELETE 0x06 SMB_COM_RENAME 0x07 SMB_COM_QUERY_INFORMATION 0x08 SMB_COM_SET_INFORMATION 0x09 SMB_COM_READ 0x0A SMB_COM_WRITE 0x0B SMB_COM_LOCK_BYTE_RANGE 0x0C SMB_COM_UNLOCK_BYTE_RANGE 0x0D SMB_COM_CREATE_TEMPORARY 0x0E SMB_COM_CREATE_NEW 0x0F SMB_COM_CHECK_DIRECTORY 0x10 SMB_COM_PROCESS_EXIT 0x11 SMB_COM_SEEK 0x12 SMB_COM_LOCK_AND_READ 0x13 SMB_COM_WRITE_AND_UNLOCK 0x14 SMB_COM_READ_RAW 0x1A SMB_COM_READ_MPX 0x1B SMB_COM_READ_MPX_SECONDARY 0x1C SMB_COM_WRITE_RAW 0x1D SMB_COM_WRITE_MPX 0x1E SMB_COM_WRITE_COMPLETE 0x20 SMB_COM_SET_INFORMATION2 0x22 SMB_COM_QUERY_INFORMATION2 0x23 SMB_COM_LOCKING_ANDX 0x24 SMB_COM_TRANSACTION 0x25 SMB_COM_TRANSACTION_SECONDARY 0x26 SMB_COM_IOCTL 0x27 SMB_COM_IOCTL_SECONDARY 0x28 SMB_COM_COPY 0x29 SMB_COM_MOVE 0x2A SMB_COM_ECHO 0x2B SMB_COM_WRITE_AND_CLOSE 0x2C SMB_COM_OPEN_ANDX 0x2D SMB_COM_READ_ANDX 0x2E SMB_COM_WRITE_ANDX 0x2F SMB_COM_CLOSE_AND_TREE_DISC 0x31 SMB_COM_TRANSACTION2 0x32 SMB_COM_TRANSACTION2_SECONDARY 0x33 SMB_COM_FIND_CLOSE2 0x34 SMB_COM_FIND_NOTIFY_CLOSE 0x35 SMB_COM_TREE_CONNECT 0x70 SMB_COM_TREE_DISCONNECT 0x71 SMB_COM_NEGOTIATE 0x72 SMB_COM_SESSION_SETUP_ANDX 0x73 SMB_COM_LOGOFF_ANDX 0x74 SMB_COM_TREE_CONNECT_ANDX 0x75 SMB_COM_QUERY_INFORMATION_DISK 0x80 SMB_COM_SEARCH 0x81 SMB_COM_FIND 0x82 SMB_COM_FIND_UNIQUE 0x83 SMB_COM_NT_TRANSACT 0xA0 SMB_COM_NT_TRANSACT_SECONDARY 0xA1 SMB_COM_NT_CREATE_ANDX 0xA2 SMB_COM_NT_CANCEL 0xA4 SMB_COM_OPEN_PRINT_FILE 0xC0 SMB_COM_WRITE_PRINT_FILE 0xC1 SMB_COM_CLOSE_PRINT_FILE 0xC2 SMB_COM_GET_PRINT_QUEUE 0xC3 Error Codes and Classes This section lists all of the valid values for Status.DosError.ErrorClass, and most of the error codes for Status.DosError.Error. The following error classes may be returned by the server to the client. Class Code Comment SUCCESS 0 The request was successful. ERRDOS 0x01 Error is from the core DOS operating system set. ERRSRV 0x02 Error is generated by the server network file manager. ERRHRD 0x03 Error is an hardware error. ERRCMD 0xFF Command was not in the "SMB" format. The following error codes may be generated with the SUCCESS error class. Class Code Comment SUCCESS 0 The request was successful. The following error codes may be generated with the ERRDOS error class. When an SMB dialect greater than equal to LANMAN 1.0 has been negotiated, all of the error codes below may be generated plus any of the error codes defined for OS/2 (see OS/2 operating system documentation for complete list of OS/2 error codes). When an earlier dialect has been negotiated, the server must map additional OS/2 (or OS/2 like) errors to the errors listed below. Error Code Description ERRbadfunc 1 Invalid function. The server did not recognize or could not perform a system call generated by the server, e.g., set the DIRECTORY attribute on a data file, invalid seek mode. ERRbadfile 2 File not found. The last component of a file's pathname could not be found. ERRbadpath 3 Directory invalid. A directory component in a pathname could not be found. ERRnofids 4 Too many open files. The server has no file handles available. ERRnoaccess 5 Access denied, the client's context does not permit the requested function. This includes the following conditions: invalid rename command write to fid open for read only read on fid open for write only attempt to delete a non-empty directory ERRbadfid 6 Invalid file handle. The file handle specified was not recognized by the server. ERRbadmcb 7 Memory control blocks destroyed. ERRnomem 8 Insufficient server memory to perform the requested function. ERRbadmem 9 Invalid memory block address. ERRbadenv 10 Invalid environment. ERRbadformat 11 Invalid format. ERRbadaccess 12 Invalid open mode. ERRbaddata 13 Invalid data (generated only by IOCTL calls within the server). ERRbaddrive 15 Invalid drive specified. ERRremcd 16 A Delete Directory request attempted to remove the server's current directory. ERRdiffdevice 17 Not same device (e.g., a cross volume rename was attempted) ERRnofiles 18 A File Search command can find no more files matching the specified criteria. ERRbadshare 32 The sharing mode specified for an Open conflicts with existing FIDs on the file. ERRlock 33 A Lock request conflicted with an existing lock or specified an invalid mode, or an Unlock requested attempted to remove a lock held by another process. ERRfilexists 80 The file named in a Create Directory, Make New File or Link request already exists. The error may also be generated in the Create and Rename transaction. ERRbadpipe 230 Pipe invalid. ERRpipebusy 231 All instances of the requested pipe are busy. ERRpipeclosing 232 Pipe close in progress. ERRnotconnected 233 No process on other end of pipe. ERRmoredata 234 There is more data to be returned. The following error codes may be generated with the ERRSRV error class. Error Code Description ERRerror 1 Non-specific error code. It is returned under the following conditions: resource other than disk space exhausted (e.g. TIDs) first SMB command was not negotiate multiple negotiates attempted internal server error ERRbadpw 2 Bad password - name/password pair in a Tree Connect or Session Setup are invalid. ERRaccess 4 The client does not have the necessary access rights within the specified context for the requested function. ERRinvnid 5 The Tid specified in a command was invalid. ERRinvnetname 6 Invalid network name in tree connect. ERRinvdevice 7 Invalid device - printer request made to non-printer connection or non- printer request made to printer connection. ERRqfull 49 Print queue full (files) -- returned by open print file. ERRqtoobig 50 Print queue full -- no space. ERRqeof 51 EOF on print queue dump. ERRinvpfid 52 Invalid print file FID. ERRsmbcmd 64 The server did not recognize the command received. ERRsrverror 65 The server encountered an internal error, e.g., system file unavailable. ERRfilespecs 67 The Fid and pathname parameters contained an invalid combination of values. ERRbadpermits 69 The access permissions specified for a file or directory are not a valid combination. The server cannot set the requested attribute. ERRsetattrmode 71 The attribute mode in the Set File Attribute request is invalid. ERRpaused 81 Server is paused. (reserved for messaging) ERRmsgoff 82 Not receiving messages. (reserved for messaging). ERRnoroom 83 No room to buffer message. (reserved for messaging). ERRrmuns 87 Too many remote user names. (reserved for messaging). ERRtimeout 88 Operation timed out. ERRnoresource 89 No resources currently available for request. ERRtoomanyuids 90 Too many Uids active on this session. ERRbaduid 91 The Uid is not known as a valid user identifier on this session. ERRusempx 250 Temporarily unable to support Raw, use MPX mode. ERRusestd 251 Temporarily unable to support Raw, use standard read/write. ERRcontmpx 252 Continue in MPX mode. ERRnosupport 65535 Function not supported. The following error codes may be generated with the ERRHRD error class. Error Code Description ERRnowrite 19 Attempt to write on write-protected media ERRbadunit 20 Unknown unit. ERRnotready 21 Drive not ready. ERRbadcmd 22 Unknown command. ERRdata 23 Data error (CRC). ERRbadreq 24 Bad request structure length. ERRseek 25 Seek error. ERRbadmedia 26 Unknown media type. ERRbadsector 27 Sector not found. ERRnopaper 28 Printer out of paper. ERRwrite 29 Write fault. ERRread 30 Read fault. ERRgeneral 31 General failure. ERRbadshare 32 A open conflicts with an existing open. ERRlock 33 A Lock request conflicted with an existing lock or specified an invalid mode, or an Unlock requested attempted to remove a lock held by another process. ERRwrongdisk 34 The wrong disk was found in a drive. ERRFCBUnavail 35 No FCBs are available to process request. ERRsharebufexc 36 A sharing buffer has been exceeded. - 97 - DRAFT This document is an early release of the final specification. It is meant to specify and accompany software that is still in development. Some of the information in this documentation may be inaccurate or may not be an accurate representation of the functionality of the final specification or software. Microsoft assumes no responsibility for any damages that might occur either directly or indirectly from these inaccuracies. Microsoft may have trademarks, copyrights, patents or pending patent applications, or other intellectual property rights covering subject matter in this document. The furnishing of this document does not give you a license to these trademarks, copyrights, patents, or other intellectual property rights