CRACK Solution

All Flipped

CRACK bitwise NOT

In-game screenshot of All Flipped
In-game view
FamilyCRACK Graph0.227 DifficultyEasy Ring02 IDllama_not

Prerequisites

THREE STEP

Unlocks

FRAMER

Accepted input KEY
Techniquebitwise NOT Rulenonzero SampleKEY

Walkthrough

Recover the accepted input below, then submit it to the CRACK verifier.

Reject Samples

  • KE
  • KEYS
  • key
  • LEY
Verifier Listing 
; llama_not: bitwise NOT cipher. Each input byte is inverted (NOT, the same as
; XOR 0xFF) and compared to a stored inverted target. NOT is self-inverse, so the
; same op decodes. Technique: bitwise NOT. r0 = 1 on accept. Accept rule: nonzero.
;
; targets = 0xB4 0xBA 0xA6  (after NOT)  ->  password "KEY".

        len   r1
        cmp   r1, 3
        jnz   bad           ; exactly 3 bytes

        mov   r7, 0
        ldb   r0, [r7]
        not   r0
        cmp   r0, 0xb4
        jnz   bad
        inc   r7
        ldb   r0, [r7]
        not   r0
        cmp   r0, 0xba
        jnz   bad
        inc   r7
        ldb   r0, [r7]
        not   r0
        cmp   r0, 0xa6
        jnz   bad

        mov   r0, 1
        ret
bad:    mov   r0, 0
        ret