; $Id: mytkExecPgm.asm,v 1.10 2000-02-23 16:53:04 bird Exp $ ; ; mytkExecPgm - tkExecPgm overload ; ; Copyright (c) 2000 knut st. osmundsen (knut.stange.osmundsen@pmsc.no) ; ; Project Odin Software License can be found in LICENSE.TXT ; .386p ; ; Include files ; include devsegdf.inc ; ; Imported Functions ; extrn _g_tkExecPgm:PROC extrn AcquireBuffer:PROC extrn ReleaseBuffer:PROC extrn QueryBufferSegmentOffset:PROC ; Scans strings until empy-string is reached. ; input: bx:di ; uses: nearly all (save bp) ; return: cx size - CF clear ; ax error- CF set extrn _f_FuStrLenZ:PROC ; Stringlength ; input: bx:di ; uses: nearly all (save bp) ; return: cx size - CF clear ; ax error- CF set extrn _f_FuStrLen:PROC ;memcpy ;input: bx:si pointer to source ; es:di pointer to target ; cx count of bytes to copy ;uses: nearly all (save bp), es, ds ;return: success CF clear ; failure CF set extrn _f_FuBuff:PROC ; ; Exported symbols ; public mytkExecPgm CODE32 SEGMENT ;; ; ; @returns same as tkExecPgm: eax, edx and carry flag ; @param ax Exec flag ; ds:dx Filename address. (String) ; es:bx Environment address. (String) ; di:si Argument address. (String) ; @uses all - bp ; @sketch Copy the filename and arguments into a buffer we ; may modify later if this is a UNIX shellscript or ; a PE-file started by pe.exe. ; @status ; @author knut st. osmundsen (knut.stange.osmundsen@pmsc.no) ; @remark ; ; The buffer we are using is a C struct as follows. ; struct Buffer ; { ; char szFilename[261]; /* offset 0 */ ; char achArg[1536-261]; /* offset 261 */ ; }; ; mytkExecPgm PROC FAR pBuffer = dword ptr -04h SegBuffer = -08h OffBuffer = -0Ch cchFilename = dword ptr -10h cchArgs = dword ptr -14h ;usExecFlag = -18h ;SegFilename = -1ch ;OffFilename = -1eh ;SegEnv = -20h ;OffEnv = -22h ;SegArg = -24h ;OffArg = -26h ASSUME CS:CODE32, DS:NOTHING, SS:NOTHING ; int 3 push ebp mov ebp, esp lea esp, [ebp + cchArgs] push eax push ecx push ds push es push edi ; parameter validations mov ax, ds ; pointer to filename cmp ax, 4 jb mytkExecPgm_CalltkExecPgm_X1 ; ; filename length ; mov ax, ds mov es, ax pushad push es push ds mov bx, ds mov di, dx ; es:di is now filename address (ds:dx). push cs ; Problem calling far into the calltab segement. call near ptr FLAT:_f_FuStrLen movzx ecx, cx mov [ebp+cchFilename], ecx pop ds pop es popad jc mytkExecPgm_CalltkExecPgm_X1; If the FuStrLen call failed we bail out! ; ; if filename length is more that CCHMAXPATH then we don't do anything!. ; cmp [ebp+cchFilename], 260 jae mytkExecPgm_CalltkExecPgm_X1; length >= 260 ; ; args length ; Note: the arguments are a series of ASCIIZs ended by an empty string (ie. '\0'). ; pop edi push edi xor ecx, ecx cmp di, 4 ; The argument might me a invalid pointer... jb mytkExecPgm_CalltkExecPgm_1 pushad push es push ds mov bx, di ; mov di, si ; bx:di -> arguments push cs ; Problem calling far into the calltab segement. call near ptr FLAT:_f_FuStrLenZ movzx ecx, cx mov [ebp+cchArgs], ecx pop ds pop es popad jc mytkExecPgm_CalltkExecPgm_X1 mytkExecPgm_CalltkExecPgm_1: mov ecx, [ebp+cchArgs] add ecx, [ebp+cchFilename] ; filename add ecx, 3 + 260 ; 260 = new argument from a scrip file or something. ; 3 = two '\0's and a space after added argument. cmp ecx, 1536 ; 1536 = Buffersize. FIXME! Define this!!! jae mytkExecPgm_CalltkExecPgm_X1; jmp if argument + file + new file > buffer size ; ; Aquire a buffer ; call AcquireBuffer or eax, eax jz mytkExecPgm_CalltkExecPgm_X1; Failed to get buffer. mov [ebp+pBuffer], eax ; ; Get Segment and offset for the buffer ; call QueryBufferSegmentOffset mov cx, es mov [ebp+OffBuffer], ax mov [ebp+SegBuffer], es test eax, 000570000h jnz mytkExecPgm_CalltkExecPgm_X2 ; ; Copy filename to pBuffer. ; pushad push es push ds mov di, ax ; es:di pBuffer mov si, dx mov bx, ds ; bx:si Filename pointer (input ds:dx) mov ecx, [ebp+cchFilename] push cs ; Problem calling far into the calltab segement. call near ptr FLAT:_f_FuBuff pop ds pop es popad jc mytkExecPgm_CalltkExecPgm_X2 ; ; Copy Args to pBuffer + 261 ; ; stack: edi, es, ds, ecx, eax pop edi push edi add eax, 261 ; we'll use eax in the branch cmp di, 4 jb mytkExecPgm_CalltkExecPgm_2 pushad push es push ds mov ecx, [ebp+cchArgs] mov bx, di ; ds:si -> arguments mov di, ax ; es:di -> buffer + 261 push cs ; Problem calling far into the calltab segement. call near ptr FLAT:_f_FuBuff pop ds pop es popad jc mytkExecPgm_CalltkExecPgm_X2 jmp mytkExecPgm_CalltkExecPgm_3 mytkExecPgm_CalltkExecPgm_2: mov word ptr es:[eax], 0 ; Terminate the empty string! ; ; Restore variables pushed on the stack ; ; stack: edi, es, ds, ecx, eax mytkExecPgm_CalltkExecPgm_3: pop edi pop es pop ds pop ecx pop eax ; ; Set new input parameters (call _g_tkExecPgm) ; ; ds:dx is to become SegBuffer:OffBuffer ; di:si is to become SegBuffer:OffBuffer+261 ; ; The some of the old values are stored on the stack (for the time being) push ds push edi push esi mov di, [ebp+SegBuffer] mov ds, di mov si, [ebp+OffBuffer] mov dx, si ; ds:dx SegBuffer:OffBuffer add si, 261 ; di:si SegBuffer:OffBuffer+261 ; ; Call _g_tkExecPgm ; push cs ; Problem calling far into the calltab segement. call near ptr FLAT:_g_tkExecPgm pushfd ; ; Release buffer ; push eax mov eax, [ebp + pBuffer] call ReleaseBuffer mov [ebp + pBuffer], 0 pop eax ; ; Return ; popfd pop esi pop edi pop ds leave retf mytkExecPgm_CalltkExecPgm_X2: ; ; Release buffer ; mov eax, [ebp + pBuffer] call ReleaseBuffer mov [ebp + pBuffer], 0 mytkExecPgm_CalltkExecPgm_X1: pop edi pop es pop ds pop ecx pop eax mytkExecPgm_CalltkExecPgm: push cs call near ptr FLAT:_g_tkExecPgm leave retf mytkExecPgm ENDP CODE32 ENDS if 0 ; alternate implementation. mytkExecPgm PROC FAR pBuffer = dword ptr -04h SegBuffer = -08h OffBuffer = -0Ch cchFilename = -10h cchArgs = -14h usExecFlag = -18h SegFilename = -1ch OffFilename = -1eh SegEnv = -20h OffEnv = -22h SegArg = -24h OffArg = -26h ASSUME CS:CODE32, DS:NOTHING, SS:NOTHING push ebp mov ebp, esp lea esp, [ebp + OffArg] ; save input parameters mov [ebp + usExecFlag], ax mov ax, es mov [ebp + SegEnv], ax mov [ebp + OffEnv], bx mov [ebp + SegArg], di mov [ebp + OffArg], si mov ax, ds mov [ebp + SegFilename], ax mov [ebp + OffFilename], dx ; parameter validations cmp ax, 4 ; pointer to filename jb mytkExecPgm_CalltkExecPgm_X1 ; ; filename length ; mov bx, ax mov di, dx ; bx:di is now filename address push cs ; Problem calling far into the calltab segement. call near ptr FLAT:_f_FuStrLen jc mytkExecPgm_CalltkExecPgm_X1; If the FuStrLen call failed we bail out! ; ; if filename length is more that CCHMAXPATH then we don't do anything!. ; cmp cx, 260 jae mytkExecPgm_CalltkExecPgm_X1; length >= 260 mov [ebp+cchFilename], cx ; ; args length ; Note: the arguments are a series of ASCIIZs ended by an empty string (ie. '\0'). ; mov bx, [ebp+SegArg] cmp bx, 4 ; The argument might me an NULL pointer xor cx, cx jb mytkExecPgm_CalltkExecPgm_1 mov di, [ebp+OffArg] ; bx:di -> arguments push cs ; Problem calling far into the calltab segement. call near ptr FLAT:_f_FuStrLenZ mov [ebp+cchArgs], cx jc mytkExecPgm_CalltkExecPgm_X1 mytkExecPgm_CalltkExecPgm_1: add cx, [ebp+cchFilename] ; filename length add cx, 3 + 260 ; 260 = new argument from a scrip file or something. ; 3 = two '\0's and a space after added argument. cmp ecx, 1536 ; 1536 = Buffersize. FIXME! Define this!!! jae mytkExecPgm_CalltkExecPgm_X1; jmp if argument + file + new file > buffer size ; ; Aquire a buffer ; call AcquireBuffer mov [ebp+pBuffer], eax or eax, eax jz mytkExecPgm_CalltkExecPgm_X1; Failed to get buffer. ; ; Get Segment and offset for the buffer ; call QueryBufferSegmentOffset mov cx, es mov [ebp+OffBuffer], ax mov [ebp+SegBuffer], es test eax, 000570000h jnz mytkExecPgm_CalltkExecPgm_X2 ; ; Copy filename to pBuffer. ; mov di, ax ; es:di pBuffer mov si, dx mov bx, ds ; bx:si Filename pointer (input ds:dx) mov cx, [ebp+cchFilename] ; cx = length of area to copy push cs ; Problem calling far into the calltab segement. call near ptr FLAT:_f_FuBuff jc mytkExecPgm_CalltkExecPgm_X2 ; ; Copy Args to pBuffer + 261 ; mov si, [ebp+SegArg] cmp si, 4 jb mytkExecPgm_CalltkExecPgm_2 mov ds, si mov si, [ebp+OffArg] ; ds:si -> arguments mov di, [ebp+SegBuffer] mov es, di mov di, [ebp+OffBuffer] add di, 261 ; es:di -> buffer + 261 mov cx, [ebp+cchArgs] ; cx = length of area to copy push cs ; Problem calling far into the calltab segement. call near ptr FLAT:_f_FuBuff jc mytkExecPgm_CalltkExecPgm_X2 jmp mytkExecPgm_CalltkExecPgm_3 mytkExecPgm_CalltkExecPgm_2: mov word ptr es:[eax], 0 ; Terminate the empty string! ; ; Set new input parameters (call _g_tkExecPgm) ; ; ds:dx is to become SegBuffer:OffBuffer ; di:si is to become SegBuffer:OffBuffer+261 ; mytkExecPgm_CalltkExecPgm_3: mov di, [ebp+SegBuffer] mov ds, di mov si, [ebp+OffBuffer] mov dx, si ; ds:dx SegBuffer:OffBuffer add si, 261 ; di:si SegBuffer:OffBuffer+261 mov bx, [ebp+SegEnv] mov es, bx mov bx, [ebp+SegEnv] ; ; Call _g_tkExecPgm ; push cs ; Problem calling far into the calltab segement. call near ptr FLAT:_g_tkExecPgm pushfd ; ; Release buffer ; push eax mov eax, [ebp + pBuffer] call ReleaseBuffer mov [ebp + pBuffer], 0 pop eax ; ; Return ; push [ebp + SegFilename] pop ds push [ebp + SegEnv] pop es popfd leave retf mytkExecPgm_CalltkExecPgm_X2: ; ; Release buffer ; mov eax, [ebp + pBuffer] call ReleaseBuffer mov [ebp + pBuffer], 0 mytkExecPgm_CalltkExecPgm_X1: pop ds mytkExecPgm_CalltkExecPgm: push cs call near ptr FLAT:_g_tkExecPgm leave retf mytkExecPgm ENDP CODE32 ENDS endif END