Simtel MSDOS 1992 June

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/ Simtel MSDOS 1992 June / SIMTEL_0692.cdr / msdos / sysutl / passwrd9.arc / PWINT.ASM < prev next >

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Assembly Source File | 1989-03-15 | 13.4 KB | 443 lines

;============================================================================ ; Title - PWINIT DATE: 3/15/89 ; This program is used with PASSWORD.ASM ; and its resulting file PASSWORD.BIN after ; compiling with MASM and converting it ; to a binary image file using EXE2BIN.EXE. ; ; The resulting EXE file will take an uninitialized ; PASSWORD.BIN file and insert the password of ; your choice and then encode the resulting ; PASSWORD.SYS file to transfer under whatever ; name you desire (as long as the name in CONFIG.SYS ; matches ie:DEVICE=PASSWORD.SYS) to your boot disk. ; I would suggest using a different name to conceal ; your intentions! ;============================================================================ Dos equ 21h ;============================================================================ code segment ; Define code segment ;============================================================================ main proc far assume cs:code,ds:data,es:file start: ; Main starting address ; Set ds to our data segment mov ax,data ;Data segment address mov ds,ax ;Move into ds register mov ax,file ;Get File segment mov es,ax ;Set es: to file segment call check_video ;See what type of monitor mov dx,offset org_file_name ;Point to Uninit file name call open_file ;Open file for read only mov old_handle,ax ;Store the handle mov bx,ax ;Set up for read mov dx,offset ds:file_buffer ;Point to file buffer area mov cx,800h ;Set number of characters push bx ;Save the file handle call read_file ;Read file into buffer mov file_size,ax ;Store number of bytes in file pop bx ;Restore the file handle call close_file ;Close the old file call clear_screen ;Clear the CRT call input_word ;Ask user for PASSWORD call box ;Clear the entry box call off_screen ;Get cursor out of box mov ax,word ptr ds:file_buffer+22 ;Get count of char to encode mov scramble_count,ax ;Store it for later mov ax,offset es:file+24 ;Point to PASSWORD address mov pass_location,ax ;Store the offset mov di,ax ;Move offset to di push di ;Save it for the moment xor cx,cx ;Zero the counter mov cl,password+1 ;Get user entered char. count inc cl ;Account for char. count mov ax,offset password+1 ;Point to user password mov si,ax ;Move pointer into si rep movsb ;Move the PASSWORD into the ;new file area pop di ;Restore es:offset to new ;file password area mov cx,scramble_count ;Load the char count to encode push ds ;Save original data segment push es pop ds ;Make ds=es mov si,di ;Make di & si point to the scramble: ;same bytes lodsb ;Get a byte sub al,40h ;Remove 40h stosb ;Store the byte loop scramble ;Loop until done pop ds ;Restore the original ds mov dx,offset new_file_name ;Point to the new file name call create_file ;Create it mov bx,ax ;Get the file handle into bx push bx ;Save it mov cx,file_size ;Load the cx with the file ;size mov dx,offset ds:file_buffer ;Point to the file buffer call write_file ;Write the new file pop bx ;Restore the file handle call close_file ;Close the new file mov ah,8fh ;Set attribute for display mov bx,offset msg_4 ;Point to the complete msg. mov cx,msg_4_len ;Length of message mov dx,0d1ch ;Location to write it call write_crt ;Display message done: mov ax,4c00h int dos ;Return to DOS main endp ;End of main program ;============================================================================ check_video proc near ;See where video RAM is mov ah,0fh ;via video ROM int 10h cmp al,07h ;See if Mono card installed jz set_mono ;Jump to monochrome routine mov video_location,0b800h ;If not mono then Color RAM jmp video_done ;Exit routine set_mono: mov video_location,0b000h ;Set location to Mono RAM video_done: ret check_video endp ;============================================================================ ;The following routines are the direct CRT display code ;============================================================================ write_crt proc near push es ;Save original es push dx ;Save location to write push ax ;Save the attribute push cx ;Save the character count push dx ;Save for the moment mov cx,02h ;Set the multiplier mov ax,video_location ;Get the address of video RAM mov es,ax ;Set the es register to RAM mov si,bx ;Point si to the message xor ax,ax ;Zero the ax mov al,dl ;Move to al the column sub al,1 ;Adjust the al imul cx ;Times to for actual column pop dx ;Get the original location mov dl,al ;Store column in dl mov al,dh ;Move into ax the row push dx ;Save for the moment sub ax,1 ;Adjust the ax mov cx,160 ;80 times 2 for actual offset imul cx pop dx ;Get dx back and dh,00h ;Zero the dh add ax,dx ;Add the column offset to the mov di,ax ;row and move di to the actual ;memory position pop cx ;Restore character count pop ax ;Restore the attribute write_crt_1: lodsb ;Load a byte of message stosw ;Store byte & attribute to RAM loop write_crt_1 ;Loop until cx=0 pop dx ;Restore original dx pop es ;restore original es ret ;And return write_crt endp ;============================================================================ write_cursor proc near off_screen: xor bx,bx ;Zero bx (page 0) and set xor dx,dx ;position to upper left corner position_cursor: mov ah,02h ;Have DOS reset the cursor int 10h ;where we want it ret ;And return clear_screen: mov ax,0600h ;Use DOS scroll to clear CRT mov bh,07 ;Set attribute xor cx,cx ;Upper left corner 0,0 mov dx,184fh ;Lower right 24,79 int 10h ret ;And return write_cursor endp ;============================================================================ ;Area to get the user password ;============================================================================ input_word proc near call box ;Make input display box mov ah,0fh ;Set attribute for display mov bx,offset msg_1 ;Point to opening mess. mov cx,msg_1_len ;Set message length mov dx,0d19h ;Location on CRT call write_crt ;Display it mov dx,0c27h ;Address for cursor xor bx,bx ;Zero bx : Page 0 call position_cursor ;set cursor to entry position mov ax,0c0ah ;Set up to use DOS buffer mov dx,offset password ;input routine (point to ;our buffer int DOS ;Get input string call box ;Clear the box mov ah,0fh ;Load attribute mov bx,offset msg_2 ;Point to next message mov cx,msg_2_len ;Load the length mov dx,0c19h ;Load where to display it call write_crt ;Write the display xor cx,cx ;Zero the count register mov cl,password+1 ;Load # of char entered mov bx,offset password+2 ;Point to the string mov dx,0c27h ;Address to display mov ah,8fh ;Load attribute call write_crt ;Display entered password ;for conformation mov ah,0fh ;Load attribute mov bx,offset msg_3 ;Point to confirm message mov cx,msg_3_len ;Length mov dx,0e19h ;Location for display call write_crt ;Display message char_loop: mov dx,0d33h ;Location for cursor xor bx,bx ;Page 0 call position_cursor ;Position cursor for input ;of a Y or N answer mov ah,0ah ;Write a blank at the cursor mov al,' ' ;to erase a answer that is mov cx,01h ;not a Y or N int 10h mov ah,01h ;Get one character int DOS and al,5fh ;Convert to upper case cmp al,'Y' ;If PASSWORD confirmed then je ok ;jump to a return cmp al,'N' ;If not, then ask for new je input_word ;password mov ax,0e07h ;If neither then ring bell int 10h ;and ask for Y or N jmp char_loop ok: ret ;PASSWORD ok. Set up ;PASSWORD.SYS input_word endp ;============================================================================ ;============================================================================ ;This routine draws a box for an entry window ;============================================================================ box proc near mov ah,04h ;Set attribute for box mov bx,offset msg_5 ;Point to Upper portion mov cx,34 ;Horizontal Length mov dx,0b17h ;Start at line 11, col 23 call write_crt ;Draw it mov bx,offset msg_6 ;Middle portion mov cx,34 ;Length mov dx,0c17h ;Start next at 12 and 23 call write_crt ;Draw it mov cx,34 ;Length mov dx,0d17h ;Start next at 13 and 23 call write_crt ;Draw it mov cx,34 mov dx,0e17h call write_crt mov bx,offset msg_7 ;Bottom portion mov cx,34 ;length mov dx,0f17h ;Start next at 14 and 23 call write_crt ;Draw it ret ;And return box endp ;============================================================================ disk_routines proc near ;============================================================================ open_file: ;Uses standard DOS function mov ax,3d00h ;to open the file int DOS ;PASSWORD.BIN jc error_1 ;Jump if does not exist ret close_file: ;Uses standard DOS function mov ah,3eh ;to close files int DOS jc error_2 ;Jump if error in closing ret write_file: ;Uses standard DOS function mov ah,40h ;to write buffer to file int DOS jc error_3 ;Jump if error writing cmp ax,cx ;See if bytes written equal jne disk_full ;filesize, if not then disk ret ;is full read_file: ;Uses standard DOS function mov ah,3fh ;to read file int DOS jc error_4 ;Jump if error in reading ret create_file: ;Uses standard DOS function mov ah,3ch ;to create a file mov cx,0 ;Set normal attribute int DOS jc error_5 ;Jump if error creating file ret error_1: call error_set_up mov dx,offset e_msg_1 jmp error_exit error_2: call error_set_up mov dx,offset e_msg_2 jmp error_exit error_3: call error_set_up mov dx,offset e_msg_3 jmp error_exit error_4: call error_set_up mov dx,offset e_msg_4 jmp error_exit error_5: call error_set_up mov dx,offset e_msg_5 jmp error_exit disk_full: call error_set_up mov dx,offset e_msg_6 jmp error_exit error_exit: mov ah,09h int DOS call off_screen mov ax,4c01h int DOS error_set_up: call box mov cx,30 mov dx,0c19h mov bx,offset disk_error mov ah,8fh call write_crt mov cx,30 mov dx,0d19h mov bx,offset blanks call write_crt mov cx,30 mov dx,0e19h mov bx,offset terminate call write_crt xor bx,bx mov dx,0c18h call position_cursor ret disk_routines endp ;============================================================================ ;============================================================================ code ends ;End of code segment ;============================================================================ ; Program Stack Area ;============================================================================ st_seg segment stack ; Define Stack Area ;============================================================================ db 20 dup ('Stack ') ;============================================================================ st_seg ends ;============================================================================ ; Data Storage areas ;============================================================================ data segment 'DATA' ; Define Data Segment ;============================================================================ msg_1 db 'Enter Password:',15 dup(20h) ;Enter Password msg_1_len dw $-msg_1 msg_2 db 'Password is : ';Password Accepted msg_2_len dw $-msg_2 msg_3 db 'Password Correct ? (Y/N) : ';Wrong Password msg_3_len dw $-msg_3 msg_4 db 'Password.SYS is complete' ;Access Denied msg_4_len dw $-msg_4 msg_5 db 201,32 dup(205),187 ;Screen Box msg_6 db 186,32 dup(20h),186 ;Screen Box msg_7 db 200,32 dup(205),188 ;Screen Box blanks db ' ' e_msg_1 db ' Opening A File$' e_msg_2 db ' Closing A File$' e_msg_3 db ' Writing A File$' e_msg_4 db ' Reading A File$' e_msg_5 db ' Creating A File$' e_msg_6 db ' Disk Full$' disk_error db ' Disk Error Occurred On ' terminate db ' Program Terminated ' ;============================================================================ password db 16,00,16 dup(0) scramble_count dw 0 pass_location dw 0 org_file_name db 'PASSWORD.BIN',0 new_file_name db 'PASSWORD.SYS',0 old_handle dw 0 new_handle dw 0 video_location dw 0 file_size dw 0 ;============================================================================ data ends ;============================================================================ ; File Buffer Area for PASSWORD.BIN ;============================================================================ file segment para 'DATA' ;============================================================================ file_buffer db 800h dup(?) ;============================================================================ file ends ;============================================================================ end start ;End of assembly