;********************************************************
;*                                                      *
;*                 N W D r v                            *
;*                                                      *
;*  Function : NetWare driver for processing "SEND",    *
;*             and "RECEIVE" operation.                 *
;*             This function is interrupt handler       *
;*             with number 6eh.                         *
;*  Input:     In AH contains function code.            *
;*             Function code may be:                    *
;*             TEST - test if int 6f handler is         *
;*                    active;                           *
;*             OPEN - open the socket for I/O           *
;*                    operation, and activate           *
;*                    interface functions. In DS:DX's   *
;*                    address of Input_Control_Record   *
;*                    (see drvicr.inc for detailes);    *
;*             CLOSE - close the socket;                *
;*             SEND - send block,                       *
;*                    DS:DX points the block for        *
;*                    transmittion;                     *
;*             DEACT - deactivisation of driver (reset  *
;*                     old INT 6fh handler and free     *
;*                     allocated memory.                *
;*             DS:DX points appropriate memory block.   *
;*  Output:    Condition code in AX.                    *
;*  Last modification: 92-12-01 17:08.                  *
;*                                                      *
;* CopyRight 1995. Nicholas Poljakov all rights reserved.*
;*                                                      *
;********************************************************
.MODEL TINY
.DOSSEG

include c:\lu62\novell\inc\ipxhdr.inc
include c:\lu62\novell\inc\seg.inc
include c:\lu62\novell\inc\drvicr.inc
include c:\m61\include\macros.inc

EXTRN DrvSend : PROC
EXTRN OffInt6f: WORD
EXTRN SegInt6f: WORD
EXTRN MyPSP : WORD

PUBLIC  int6f, Rcv_Exit, Rcv_off, ipxProc, CheckAddr, ipxECB, CancelECB
PUBLIC  Rcv_seg, Codes, ExTable, bufArea, PStart, DrvOpen, OpExit
PUBLIC  DrvClose, Deact, Dummy, RcvESR, RcvContin, PrepECB, DrvTest
PUBLIC  ActLU, ActLuMsg, LocalS, StAddrCycl, CallDrvSend


OPEN     EQU   00h
SEND     EQU   01h
CLOSE    EQU   02h
DEACT    EQU   03h
CHKADDR  EQU   04h
TESTEX   EQU   33h


.CODE
int6f    PROC  FAR

         jmp   PStart

ipxProc  DD    0    ; IPX entry point
Rcv_Exit DD    0
         ORG   Rcv_Exit
Rcv_off  DW    ?
Rcv_seg  DW    ?

Codes    DB    OPEN,CLOSE,SEND,DEACT,CHKADDR,TESTEX,255
Count    EQU   $ - Codes
ExTable  DW    DrvOpen
         DW    DrvClose
         DW    DrvSend
         DW    Deact
         DW    CheckAddr
         DW    DrvTest
         DW    Dummy

ipxECB   IPXECB <>
ipxHDR   IPXHDR <>
ipxAddr  INTADDR <>     ; IPX internetwork address
ImmAddr  DB  6 DUP(?)   ; Immediate Address of node.
bufArea  DB 546 dup(0)

LocalS   DB    0        ; "Local_Send" indicator
MsgFrom  DB    0        ; First byte of Node Address
ActLuMsg SEGPRF <, 9, 0>
RQB      DB    16 dup(0) ; reserved RQD field
MsgTag   DB    1
NameLu   DB    0,0,0,0,0,0,0,0 ; Activate LU message

PStart:
         @SaveRegs ax,bx,cx,ds,dx,si,di,es,bp
         mov   bp, sp

         sti
         mov   cx, cs
         mov   ds, cx
         mov   cx, Count
         mov   di, OFFSET Codes
         push  cs
         pop   es
         mov   al, ah
         cld
         repne scasb
         sub   di,(OFFSET Codes)+1   ; Point to key
         shl   di,1                  ; Adjust pointer for word addresses
         call  ExTable[di]           ; Call procedure
         jc    IntExit               ; return code was already set.
         mov   WORD PTR [bp + 16], ax ; set RETURN CODE in AX

IntExit:
         @RestoreRegs
         iret

int6f    ENDP

DrvOpen  PROC
;***************************************************
;*    First, fetch address of IPX entry point      *
;***************************************************

         mov   ax, 7a00h
         int   2fh
         cmp   al, 0ffh
         je    IPXexist
         mov   ax, 0ffffh
         jmp   OpExit   ; in ax - bad return code
IPXexist:
         mov   ax, es
         mov   WORD PTR ipxProc, di
         mov   WORD PTR ipxProc + 2, ax

;   Set Rcv_Exit value

         les   bx, DWORD PTR [bp + 8]   ; input DX value
         mov   ax, WORD PTR es:[bx].RcvSbr
         mov   Rcv_off, ax
         mov   ax, WORD PTR es:[bx].RcvSbr + 2
         mov   Rcv_seg, ax

;***************************************************
;     Second, Open the socket...                   *
;***************************************************

         xor   bx, bx       ; open socket function
         mov   ax, 0ffffh   ; open until closed
         mov   dx, MY_SOCKET
         call  ipxProc
         and   ax, ax       ; is it O.K! ?
         jnz   OpExit       ; no... exit.

;***************************************************
;*   Then  send "Activate_LU" broadcasting message *
;*   and set "listening" request                   *
;***************************************************

         call  ActLU
         call  PrepECB

;  And exit...

OpExit:
         clc
         ret
DrvOpen  ENDP

DrvClose PROC

;  Close my socket

         mov   bx, 1
         mov   dx, MY_SOCKET
         call  ipxProc

         clc
         ret
DrvClose ENDP

;***************************************************
;*                                                 *
;*     Deactivation LU procedure.                  *
;*                                                 *
;*  Function : 1). Sends broadcasting message      *
;*                 "Deactivate_LU".                *
;*             2). Close socket.                   *
;*             3). Restore pointer to old INT 6fh  *
;*                 handler.                        *
;*             4) And free the memory allocated for*
;*                this program.                    *
;*                                                 *
;***************************************************
Deact    PROC
;*
;*  Send broadcasting "Deactivisation_LU" message
;*
         mov   ipxHDR.PType, 0    ; control packet
         mov   MsgTag, 2
         call  ActLU

;*  Close my socket

         mov   bx, 1
         mov   dx, MY_SOCKET
         call  ipxProc
;*
;*  Restory Old Int6fh vector
;*
         cli
         mov   ax, 10h
         mov   es, ax
         mov   ax, OffInt6f
         mov   WORD PTR es:[0bch], ax  ; Old INT6f, offset
         mov   ax, SegInt6f
         mov   WORD PTR es:[0beh], ax  ; Old INT6f, segment
         sti

;*
;*  And free program segment...
;*
         mov   ax, MyPSP
         mov   es, ax
         mov   ax, 4900h
         int   21h        ; Free code segment

         clc
         ret
Deact    ENDP

Dummy    PROC
         clc
         ret
Dummy    ENDP

CheckAddr PROC
;***************************************************
;*                                                 *
;*   Check Node address before send block to it.   *
;*                                                 *
;***************************************************

          les  bx, DWORD PTR [bp + 8]  ; input DS:DX values

;         Prepare Address buffer

          mov  ax, WORD PTR es:[bx]
          mov  WORD PTR ipxAddr.NodeAddr, ax
          mov  ax, WORD PTR es:[bx + 2]
          mov  WORD PTR ipxAddr.NodeAddr + 2, ax
          mov  ax, WORD PTR es:[bx + 4]
          mov  WORD PTR ipxAddr.NodeAddr + 4, ax
          mov  si, OFFSET ipxAddr
          mov  di, OFFSET ImmAddr
          mov  bx, cs
          mov  es, bx
          mov  bx, 2
          call ipxProc  ; get local target for input node address
          xor  ah, ah
          and  ax, ax   ; check return code from IPX
          jnz  ChkExit  ; bad return code... exit.

          mov  di, WORD PTR [bp + 8]   ; input DX value
          mov  ax, WORD PTR [bp + 12]  ; input DS value
          mov  es, ax
          mov  si, OFFSET ImmAddr
          mov  cx, cs
          mov  ds, cx
          mov  cx, 6
          cld
          rep  movsb    ; copy returned address to field
                        ; that pointes by input DS:DX
          xor  ax, ax   ; O.K! return code

ChkExit:
          clc
          ret
CheckAddr ENDP


;***************************************************
;*                                                 *
;*   ESR for receiving incoming packet.            *
;*   ES:SI points to appropriate ECB.              *
;*   AX - source indicator                         *
;*                                                 *
;***************************************************
RcvESR   PROC  FAR
         cli
         mov   cx, cs
         mov   ds, cx

         cmp   ipxECB.RetCode,0 ; is it normal receive ?
         jne   RcvContin
         les   di, ipxECB.SAddr ; address of data block
         mov   cl, BYTE PTR es:[di] ; first byte of Network Address
         mov   MsgFrom, cl      ; Save first byte of Node address
         lea   si, ipxECB.PAddr ; pointer to partner address field
         mov   cx, 6
         cld
         rep   movsb            ; mov p. addr. in SEGPRF.PAddr
         les   si, ipxECB.FAddr ; ES:SI pointes to IPX header
         mov   cx, es:[si].PLt  ; total length of received data block
         xchg  ch, cl
         sub   cx, 30           ; length of data block
         mov   dx, WORD PTR ipxECB.SAddr
         mov   ax, WORD PTR ipxECB.SAddr + 2
         xor   bh, bh
         mov   bl, ipxHDR.PType ; packet type
         push  ds
         mov   ds, ax           ; DS:DX now points to input buffer
         mov   ax,  bx          ; message type indicator
         pushf                  ; Call "_interrupt" function for read block
         call  Rcv_Exit
         pop   ds
         and   bx, bx           ; is it a control message ?
         jnz   RcvContin        ; no...
         les   bx, ipxECB.SAddr ; ES:BX points to message field
         cmp   BYTE PTR es:[bx + PRFLT], 2  ; is it "Deactivate_LU" message ?
         je    RcvContin
         cmp   MsgFrom, 0ffh    ; is it broadcasting message ?
         jne   RcvContin
         mov   si, bx
         mov   di, OFFSET ActLuMsg
         mov   cx, 6
         cld
         rep   movsb            ; set address of source of message
         call  ActLU            ; send response to "Activate_Lu"
                                ; message

RcvContin:
         call  PrepECB

         ret
RcvESR   ENDP

PrepECB  PROC

;     Prepare ECB for receivig packets

         cmp   ipxECB.InUse, 0feh          ; is ECB in listening mode?
         je    PrepExit
         mov   ax, OFFSET RcvESR
         mov   WORD PTR ipxECB.ESR, ax     ; set ESR address
         mov   ax, cs                      ; for
         mov   WORD PTR ipxECB.ESR + 2, ax ; block receiving
         mov   ipxECB.SocNum, MY_SOCKET
         mov   bx, OFFSET ipxHDR
         mov   WORD PTR ipxECB.FAddr, bx   ; set ipx header address
         mov   WORD PTR ipxECB.FAddr + 2, ax
         mov   ipxECB.FLt, 30              ; length of ipx header
         mov   bx, OFFSET bufArea
         mov   WORD PTR ipxECB.SAddr, bx   ; set address of data block
         mov   WORD PTR ipxECB.SAddr + 2, ax
         mov   ipxECB.SLt, 546             ; length of data block
         mov   ipxECB.FragNum, 2           ; two fragments

         mov   bx, cs
         mov   es, bx
         mov   bx, 4
         mov   si, offset ipxECB
         call  ipxProc

PrepExit:
         ret
PrepECB  ENDP

DrvTest  PROC
         mov   WORD PTR [bp + 16], 5555h ; set output AX value
                                         ; 5555h - indicates that
                                         ; int 6fh is exist.
         xor   ax, ax                    ; local return code
         stc                             ; to prevent reset
                                         ; global return code
         ret
DrvTest  ENDP

CancelECB PROC
	 @SaveRegs ax,bx,cx,si,es
CnPrep:
         mov   si, cs
         mov   es, si
         mov   si, OFFSET ipxECB
         mov   bx, 6    ; cancel request
         call  ipxProc
         and   al, al
         jz    CnExit
         cmp   al, 0ffh
         je    CnExit
         cmp   al, 0ffh
         jne   CnExit

         mov   cx, 0ffffh
         sti
WaitCycl:
         loop  WaitCycl ; wait for end of transmittion
         jmp   short CnPrep

CnExit:
	 @RestoreRegs
         ret
CancelECB ENDP

;***************************************************
;*                                                 *
;*         Activate LU procedure.                  *
;* Function: Send broadcasting "Activate_LU"       *
;*           message.                              *
;*                                                 *
;***************************************************

ActLU    PROC

; Set address of broadcasting message.

         cmp   ipxHDR.PType, 0    ; is it response to control message?
         je    CallDrvSend        ; yes, skip address and name setting

         mov   bx, OFFSET ActLuMsg
         mov   cx, 6
StAddrCycl:
         mov   BYTE PTR cs:[bx], 0ffh
         inc   bx
         loop  StAddrCycl

; Set Lu_Name field in "Activate_LU" message.

         lds   si, DWORD PTR [bp + 8]  ; input DS:DX values
         lea   si, ds:[si].LuName
         mov   di, cs
         mov   es, di
         mov   di, OFFSET NameLu
         mov   cx, 8
         cld
         rep   movsb        ; move LU name begins to RH + 1 location
         mov   ax, cs
         mov   ds, ax

; Call "DrvSend function".

CallDrvSend:
         mov   LocalS, 1     ; ON a "local_send" operation
         call  DrvSend
         mov   LocalS, 0     ; OFF a "local_send" operation

         ret
ActLU    ENDP

         END