corCTF 2024：位运算虚拟机及gpu hash爆破

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FizzBuzz101 was innocently writing a new, top-secret compiler when his computer was Crowdstriked. Worse, the recovery key is behind a hasher that he wrote and compiled himself, and he can't remember how the bits work! Can you help him get his life's work back? FizzBuzz101 正在无辜地编写一个新的绝密编译器，这时他的电脑遭到了 Crowdstriked。更糟糕的是，恢复密钥在他自己编写和编译的哈希器后面，他不记得这些位是如何工作的！你能帮他找回他一生的工作吗？ 一 初步分析 0x1290~0xED853有一坨mov byte导致main函数f5不了 0x1290~0x136F： mov byte ptr [rax+x], 1 ，x范围是120h到13Fh 0x1370~0x16EF： mov byte ptr [rax+x], 0 ，x范围是0FA0h到101Fh 0x16F0~0x1E6E：or运算 mov cl, [rax+0FA0h] or cl, [rax+100h] mov [rax+0], cl 0x1E6F~0x566E： mov byte ptr [rax+x], y ，赋值0或1 0x566F~0x57EE：and运算 0x57EF~0x59CE：xor运算 0x59CF~0x5BAE：and运算 ... 一直持续到0xED853。 猜测 ………………………………