windows-nt/Source/XPSP1/NT/net/rras/ndis/asyncmac/frame.h

/*++

Copyright (c) 1992  Microsoft Corporation

Module Name:

    frame.h

Abstract:

Author:

    Thomas J. Dimitri  (TommyD) 08-May-1992

Environment:

    Kernel Mode - Or whatever is the equivalent on OS/2 and DOS.

Revision History:


--*/

// first, some default values

// the ethernet max frame size is 1500+6+6+2  = 1514

/* Note that this only applies to non-PPP framing.  See below.
*/
#define DEFAULT_MAX_FRAME_SIZE  1514

/* The hard-coded PPP maximum frame sizes for send and receive paths.
**
** Note:  TommyD had these hard-coded.  I have simply made this more explicit
**        by removing their attachment to MaxFrameSize which was causing
**        problems for NT31 RAS compression.  The doubling is for PPP
**        byte-stuffing, the PPP_PADDING to adjust for possible VJ expansion,
**        and the 100...well, ask TommyD...and the 14 to limit exposure, i.e.
**        wind up with the exact number TommyD was using.
*/
#define DEFAULT_PPP_MAX_FRAME_SIZE          1500
#define DEFAULT_EXPANDED_PPP_MAX_FRAME_SIZE ((DEFAULT_PPP_MAX_FRAME_SIZE*2)+PPP_PADDING+100+14)

// ChuckL says 5 is a good default irp stack size
// perhaps we should lower this though since it's typically just 1
// but what if the com port is redirected??
#define DEFAULT_IRP_STACK_SIZE  5

#define SLIP_END_BYTE       192
#define SLIP_ESC_BYTE       219
#define SLIP_ESC_END_BYTE   220
#define SLIP_ESC_ESC_BYTE   221


#define PPP_FLAG_BYTE       0x7e
#define PPP_ESC_BYTE        0x7d


// define the number of framesPerPort

/* The NT35 setting, where sends are IRPed directly from the input buffer
** passed down from NDISWAN.
*/
#define DEFAULT_FRAMES_PER_PORT 1

// define if xon/xoff capability is on by default (off)
#define DEFAULT_XON_XOFF    0

// the mininmum timeout value per connection in ms
#define DEFAULT_TIMEOUT_BASE 500

// the multiplier based on the baud rate tacked on to the base in ms
#define DEFAULT_TIMEOUT_BAUD 28800

// the timeout to use if we drop a frame in ms
#define DEFAULT_TIMEOUT_RESYNC 500


typedef struct ASYNC_FRAME_HEADER ASYNC_FRAME_HEADER, *PASYNC_FRAME_HEADER;

struct ASYNC_FRAME_HEADER {
    UCHAR   SyncByte;           // 0x16
    UCHAR   FrameType;          // 0x01, 0x02 (directed vs. multicast)
                                // 0x08 compression
    UCHAR   HighFrameLength;
    UCHAR   LowFrameLength;
};

typedef struct ASYNC_FRAME_TRAILER ASYNC_FRAME_TRAILER, *PASYNC_FRAME_TRAILER;

struct ASYNC_FRAME_TRAILER {
    UCHAR   EtxByte;            // 0x03
    UCHAR   LowCRCByte;
    UCHAR   HighCRCByte;
};

typedef ULONG  FRAME_ID;

typedef struct ASYNC_ADAPTER ASYNC_ADAPTER, *PASYNC_ADAPTER;
typedef struct ASYNC_INFO ASYNC_INFO, *PASYNC_INFO;
typedef struct ASYNC_FRAME ASYNC_FRAME, *PASYNC_FRAME;

struct ASYNC_FRAME {

    // For PPP/SLIP.

    ULONG       WaitMask;               // Mask bits when IRP completes
#if 0
    PIRP        Irp;                    // Irp allocated based on DefaultIrpStackSize.
#if DBG
    ULONG       Line;
    CHAR       *File;
#endif
#endif

    UINT        FrameLength;            // Size of Frame allocated.
    PUCHAR      Frame;                  // Buffer allocated based on
                                        // DefaultFrameSize

    WORK_QUEUE_ITEM WorkItem;           // For stack overflow reads

    PASYNC_ADAPTER      Adapter;        // back ptr to adapter
    PASYNC_INFO         Info;           // back ptr to info field

    NDIS_HANDLE     MacBindingHandle;
    NDIS_HANDLE     NdisBindingContext;
};

NTSTATUS
AsyncGetFrameFromPool(
    IN  PASYNC_INFO  Info,
    OUT PASYNC_FRAME *NewFrame );