/*++ Copyright (c) 1989 Microsoft Corporation Module Name: NpStruc.h Abstract: This module defines the data structures that make up the major internal part of the Named Pipe file system. Author: Gary Kimura [GaryKi] 20-Aug-1990 Revision History: --*/ #ifndef _NPSTRUC_ #define _NPSTRUC_ // // The VCB record is the top record in the Named Pipe file system in-memory // data structure. This structure must be allocated from non-paged pool // and immediately follows (in memory) the Device object for the named // pipe. Structurally the layout of the data structure is as follows // // +------------+ // |NPDO | // | | // +------------+ // |Vcb | // | | // | EventTable | // | WaitQueue | // | | // +------------+ // | ^ // | | // | | // v | // +-------------+ // |RootDcb | // | |<-+ // +-------------+ | // | | // v | // +-------------+ | // |NonPaged | | // | | | // +-------------+ | // : | // : | // : | // v | // +----------------+ +-------------------+ +---------+ // |Fcb | |Ccb | |ServerFO | // | |<---| | | | // | MaxInstances | | ServerFO |<-------|- 1| // | CurrentInst | | ClientFO | | | // | DefaultTimeOut |...>| |<-+ +--|- | // | | | | | | | | // +----------------+ +-------------------+ | | +---------+ // | | | | // v v | | // +----------------+ +-------------------+ | | +---------+ // |NonPagedFcb | |NonPagedCcb |<-|--+ |ClientFO | // | |<---| | | | | // | PipeConfig | | PipeState | +-----|- 0| // | PipeType | | ReadMode[2] | | | // | | | CompletionMode[2] |<-------|- | // | | | CreatorProcess | | | // | | | EventTabEnt[2] | +---------+ // | | | DataQueue[2] | // | | | | (low bit determines // +----------------+ +-------------------+ server/client) // // // Where there is only one Vcb for the entire Named Pipe file system, and // it contains a single pointer to the root dcb for the file system. Off // of the Dcb is a queue of Fcb's. There is one Fcb for every named pipe. // There is one Ccb for every instance of a named pipe. There are also // two additional ccb types for the vcb and the root dcb, and notify records // for the notify change operations. // // A newly initialized named pipe file system only contains the Vcb and // the root dcb. A new Fcb is created when a new named pipe is created // and then a ccb must also be created. The file object for the creater // (i.e., server end) points to the ccb and indicates that it is the server // end. When a user does an open on the named pipe its file object is // set to point to the same ccb and is also set to indicate that it is the // client end. This is denoted by using the last bit of the FsContext pointer // if the bit is 1 it is a server end file object, if the bit is 0 it is // the client end. // // A file object with a null pointer to the FsContext field is a closed or // disconnected pipe. // // The Ccb also contains back pointer to the file objects that have it opened // // // The following types are used to help during development by keeping the // data types distinct. The manifest contants that go in each is declared // in the ntioapi.h file // typedef ULONG NAMED_PIPE_TYPE; typedef NAMED_PIPE_TYPE *PNAMED_PIPE_TYPE; typedef ULONG READ_MODE; typedef READ_MODE *PREAD_MODE; typedef ULONG COMPLETION_MODE; typedef COMPLETION_MODE *PCOMPLETION_MODE; typedef ULONG NAMED_PIPE_CONFIGURATION; typedef NAMED_PIPE_CONFIGURATION *PNAMED_PIPE_CONFIGURATION; typedef ULONG NAMED_PIPE_STATE; typedef NAMED_PIPE_STATE *PNAMED_PIPE_STATE; typedef ULONG NAMED_PIPE_END; typedef NAMED_PIPE_END *PNAMED_PIPE_END; // // The following two types are used by the event table package. The first // is the event table itself which is just a generic table. It is protected // by the vcb resource, and the second structure is an event table entry. // typedef struct _EVENT_TABLE { RTL_GENERIC_TABLE Table; } EVENT_TABLE; typedef EVENT_TABLE *PEVENT_TABLE; // // The event table is a generic table of event table entries. Each Ccb // optionally contains a pointer to an event table entry for each direction. // The entries are part of the global event table defined off of the Vcb // typedef struct _EVENT_TABLE_ENTRY { // // The first two fields are used as keys in the generic table's // comparison routines. The pipe end will either be FILE_PIPE_CLIENT_END // or FILE_PIPE_SERVER_END. // struct _CCB *Ccb; NAMED_PIPE_END NamedPipeEnd; // // The following three fields are used to identify the event entry // to the named pipe user // HANDLE EventHandle; PVOID Event; ULONG KeyValue; PEPROCESS Process; } EVENT_TABLE_ENTRY; typedef EVENT_TABLE_ENTRY *PEVENT_TABLE_ENTRY; // // Each Ccb has two data queues for holding the outstanding in-bound and // out-bound read/write requests. The following type is used to determine // if the data queue contains read requests, write requests, or is empty. // typedef enum _QUEUE_STATE { ReadEntries, WriteEntries, Empty } QUEUE_STATE; // // The data queue is a structure that contains the queue state, quota // information, and the list head. The quota information is used to // maintain pipe quota. // typedef struct _DATA_QUEUE { // // This is the head of a queue of data entries (singly linked) // LIST_ENTRY Queue; // // The current state of what is contained in this data queue, // how many bytes of read/write data there are, and how many individual // requests there are in the queue that contain data (includes // close or flush requests). // QUEUE_STATE QueueState; ULONG BytesInQueue; ULONG EntriesInQueue; // // The following two fields denote who much quota was reserved for // this pipe direction and how much we've used up. This is only // the creator quota and not the user quota. // ULONG Quota; ULONG QuotaUsed; // // The following field indicates how far we've already processed // into the first entry in the data queue // ULONG NextByteOffset; } DATA_QUEUE; typedef DATA_QUEUE *PDATA_QUEUE; // // Each data entry has a type field that tells us if the operation // for the entry is buffered, unbuffered, flush, or a close entry. // typedef enum _DATA_ENTRY_TYPE { Buffered, Unbuffered, Flush, Close } DATA_ENTRY_TYPE; // // The following type is used to denote where we got the memory for the // data entry and possibly the data buffer. We either got the memory // from the pipe quota, the user quota, or it is part of the next IRP stack // location. // typedef enum _FROM { PipeQuota, UserQuota, InIrp } FROM; // // Each entry in the data queue is a data entry. Processing an IRP // has the potential of creating and inserting a new data entry. If the // memory for the entry is taken from the IRP we use the next stack // location. // typedef struct _DATA_ENTRY { // // The following field is how we connect into the queue of data entries // LIST_ENTRY Queue; // // The following field indicates if we still have an IRP associated // with this data entry that need to be completed when the remove // the data entry. Note that if From is InIrp that this IRP field // must not be null. // PIRP Irp; // // The following field is used to point to the client context if dynamic // impersonation is being used // PSECURITY_CLIENT_CONTEXT SecurityClientContext; // // The following field describe the type of data entry // ULONG DataEntryType; // // Record the amount of quota charged for this request. // ULONG QuotaCharged; // // The following field describes the size of the data // buffer described by this entry. // ULONG DataSize; // // Start of the data buffer if it exists // UCHAR DataBuffer[]; } DATA_ENTRY; typedef DATA_ENTRY *PDATA_ENTRY; // // The following type is used by the wait queue package // typedef struct _WAIT_QUEUE { LIST_ENTRY Queue; KSPIN_LOCK SpinLock; } WAIT_QUEUE; typedef WAIT_QUEUE *PWAIT_QUEUE; typedef struct _VCB { // // The type of this record (must be NPFS_NTC_VCB) // NODE_TYPE_CODE NodeTypeCode; // // The following field is used to check share access people who want // to open the named pipe driver // SHARE_ACCESS ShareAccess; // // A pointer to the root DCB for this volume // struct _FCB *RootDcb; // // A count of the number of file objects that have opened the \NamedPipe // object directly, and also a count of the number of file objects // that have opened a name pipe or the root directory. // CLONG OpenCount; // // A prefix table that is used for quick, prefix directed, lookup of // FCBs/DCBs that are part of this volume // UNICODE_PREFIX_TABLE PrefixTable; // // A resource variable to control access to the volume specific data // structures // ERESOURCE Resource; // // The following table is used to hold the named pipe events // EVENT_TABLE EventTable; // // The following field is a queue of waiting IRPS of type WaitForNamedPipe // WAIT_QUEUE WaitQueue; } VCB; typedef VCB *PVCB; // // The Named Pipe Device Object is an I/O system device object with // additional workqueue parameters appended to the end. There is only // one of these records created for the entire system during system // initialization. // typedef struct _NPFS_DEVICE_OBJECT { DEVICE_OBJECT DeviceObject; // // This is the file system specific volume control block. // VCB Vcb; } NPFS_DEVICE_OBJECT; typedef NPFS_DEVICE_OBJECT *PNPFS_DEVICE_OBJECT; // // The Fcb/Dcb record corresponds to every opened named pipe and directory, // and to every directory on an opened path. // // The structure is really divided into two parts. FCB can be allocated // from paged pool which the NONPAGED_FCB must be allocated from non-paged // pool. // typedef struct _FCB { // // Type of this record (must be NPFS_NTC_FCB, or // NPFS_NTC_ROOT_DCB) // NODE_TYPE_CODE NodeTypeCode; // // The links for the queue of all fcbs for a specific dcb off of // Dcb.ParentDcbQueue. For the root directory this queue is empty // LIST_ENTRY ParentDcbLinks; // // A pointer to the Dcb that is the parent directory containing // this fcb. If this record itself is the root dcb then this field // is null. // struct _FCB *ParentDcb; // // A pointer to the Vcb containing this fcb // PVCB Vcb; // // A count of the number of file objects that have opened // this file/directory. For a pipe this is also the number of instances // created for the pipe. // CLONG OpenCount; // // A count of the number of server end file objects that have opened // this pipe. ServerOpenCount is incremented when OpenCount is // incremented (when the server end creates an instance), but is // decremented when the server end handle is closed, where OpenCount // isn't decremented until both side's handles are closed. When // ServerOpenCount is 0, a client's attempt to open a named pipe is // met with STATUS_OBJECT_NAME_NOT_FOUND, not STATUS_PIPE_NOT_AVAILABLE, // based on an assumption that since the server doesn't think it has // any instances open, the pipe really doesn't exist anymore. An // example of when this distinction is useful is when the server // process exits, but the client processes haven't closed their // handles yet. // CLONG ServerOpenCount; // // The following field points to the security descriptor for this named pipe // PSECURITY_DESCRIPTOR SecurityDescriptor; // // The following union is cased off of the node type code for the fcb. // There is a seperate case for the directory versus file fcbs. // union { // // A Directory Control Block (Dcb) // struct { // // A queue of the notify IRPs that will be completed when any // change is made to a file in the directory. Enqueued using // the Tail.Overlay.ListEntry of the Irp. // LIST_ENTRY NotifyFullQueue; // // A queue of the notify IRPs that will be completed only if a // file is added, deleted, or renamed in the directory. Enqueued // using the Tail.Overlay.ListEntry of the Irp. // LIST_ENTRY NotifyPartialQueue; // // A queue of all the fcbs/dcbs that are opened under this // Dcb. // LIST_ENTRY ParentDcbQueue; // // The following field is used to check share access people // who want to open the directory. // SHARE_ACCESS ShareAccess; } Dcb; // // An File Control Block (Fcb) // struct { // // This is the maximum number of instances we can have for the // named pipe and the current number of instances is the open // count for the fcb (note that the current number also // correspondsto the number of Ccbs) // ULONG MaximumInstances; // // The assigned pipe configuration (FILE_PIPE_INBOUND, // FILE_PIPE_OUTBOUND, or FILE_PIPE_FULL_DUPLEX) and pipe // type (FILE_PIPE_MESSAGE_TYPE or // FILE_PIPE_BYTE_STREAM_TYPE). // NAMED_PIPE_CONFIGURATION NamedPipeConfiguration : 16; NAMED_PIPE_TYPE NamedPipeType : 16; // // The following field is the default timeout assigned to the // named pipe // LARGE_INTEGER DefaultTimeOut; // // The Following field is a queue head for a list of ccbs // that are opened under us // LIST_ENTRY CcbQueue; } Fcb; } Specific; // // The following field is the fully qualified file name for this FCB/DCB // starting from the root of the volume, and last file name in the // fully qualified name. // UNICODE_STRING FullFileName; UNICODE_STRING LastFileName; // // The following field contains a prefix table entry that is used when // searching a volume for a name (or longest matching prefix) // UNICODE_PREFIX_TABLE_ENTRY PrefixTableEntry; } FCB, DCB, ROOT_DCB; typedef FCB *PFCB; typedef DCB *PDCB; typedef ROOT_DCB *PROOT_DCB; typedef struct _CLIENT_INFO { PVOID ClientSession; USHORT ClientComputerNameLength; WCHAR ClientComputerBuffer[]; } CLIENT_INFO, *PCLIENT_INFO; // // The Ccb record is allocated for every opened instance of a named pipe. // There are two parts to a ccb a paged part and a Nonpaged part. Both // parts are pointed at by the FsContext and FsContext2 field of a file // object. // typedef struct _CCB { // // Type of this record (must be NPFS_NTC_CCB). // NODE_TYPE_CODE NodeTypeCode; // // Pipe state indicates the current state of the pipe // (FILE_PIPE_DISCONNECTED_STATE, FILE_PIPE_LISTENING_STATE, // FILE_PIPE_CONNECTED_STATE, or FILE_PIPE_CLOSING_STATE). // UCHAR NamedPipeState; // // read mode (FILE_PIPE_MESSAGE_MODE or FILE_PIPE_BYTE_STREAM_MODE), // and completion mode (FILE_PIPE_QUEUE_OPERATION or // FILE_PIPE_COMPLETE_OPERATION) describe how to handle requests to the // pipe. Both of these fields are indexed by either FILE_PIPE_SERVER_END // or FILE_PIPE_CLIENT_END. // struct { UCHAR ReadMode : 1; UCHAR CompletionMode : 1; } ReadCompletionMode[2]; // // Stored client impersonation level // SECURITY_QUALITY_OF_SERVICE SecurityQos; // // The following field is a list entry for the list of ccb that we // are a member of // LIST_ENTRY CcbLinks; // // A pointer to the paged Fcb, or Vcb that we are tied to // PFCB Fcb; // // Back pointers to the server and client file objects that have us // opened. This is indexed by either FILE_PIPE_CLIENT_END or // FILE_PIPE_SERVER_END. // PFILE_OBJECT FileObject[2]; // // The following fields contain the session and process IDs of the // client side of the named pipe instance. They are originally set // to NULL (indicating local session) and the real client process // ID but can be changed via FsCtl calls. // PVOID ClientProcess; PCLIENT_INFO ClientInfo; // // A pointer to the Nonpaged part of the ccb // struct _NONPAGED_CCB *NonpagedCcb; // // The following data queues are used to contain the buffered information // for each direction in the pipe. They array is indexed by // PIPE_DIRECTION. // DATA_QUEUE DataQueue[2]; // // Stored client security for impersonation // PSECURITY_CLIENT_CONTEXT SecurityClientContext; // // A queue of waiting listening IRPs. They are linked into the // Tail.Overlay.ListEntry field in the Irp. // LIST_ENTRY ListeningQueue; } CCB; typedef CCB *PCCB; typedef struct _NONPAGED_CCB { // // Type of this record (must be NPFS_NTC_NONPAGED_CCB) // NODE_TYPE_CODE NodeTypeCode; // // The following pointers denote the events we are to signal for the // server and client ends of the named pipe. The actual entry // is stored in the event table, and referenced here for easy access. // The client end is signaled if ever a read/write occurs to the client // of the pipe, and likewise for the server end. The array is // indexed by either FILE_PIPE_SERVER_END or FILE_PIPE_CLIENT_END. // PEVENT_TABLE_ENTRY EventTableEntry[2]; // // Resource for synchronizing access // ERESOURCE Resource; } NONPAGED_CCB; typedef NONPAGED_CCB *PNONPAGED_CCB; // // The Root Dcb Ccb record is allocated for every opened instance of the // root dcb. This record is pointed at by FsContext2. // typedef struct _ROOT_DCB_CCB { // // Type of this record (must be NPFS_NTC_ROOT_DCB_CCB). // NODE_TYPE_CODE NodeTypeCode; // // The following field is a count of the last index returned // by query directory. // ULONG IndexOfLastCcbReturned; // // The following string is used as a query template for directory // query operations // PUNICODE_STRING QueryTemplate; } ROOT_DCB_CCB; typedef ROOT_DCB_CCB *PROOT_DCB_CCB; #endif // _NPSTRUC_