传入1个数字参数
pop eax
pop edx
结果判断是edx和eax是否为0
005D80FB . 83FA 00 cmp edx, 0
005D80FE . 75 29 jnz short 005D8129 ; 不能跳
005D8100 . 83F8 00 cmp eax, 0
005D8103 . 75 24 jnz short 005D8129 ; 不能跳
函数入口
00405644 /$ 55 push ebp
00405645 |. 53 push ebx
00405646 |. 56 push esi
00405647 |. 57 push edi
00405648 |. 31FF xor edi, edi
0040564A |. 8B5C24 14 mov ebx, dword ptr [esp+14]
0040564E |. 8B4C24 18 mov ecx, dword ptr [esp+18]
00405652 |. 09C9 or ecx, ecx
00405654 |. 75 08 jnz short 0040565E
00405656 |. 09D2 or edx, edx
00405658 |. 74 5D je short 004056B7
0040565A |. 09DB or ebx, ebx
0040565C |. 74 59 je short 004056B7
0040565E |> 09D2 or edx, edx
00405660 |. 79 0A jns short 0040566C
00405662 |. F7DA neg edx
00405664 |. F7D8 neg eax
00405666 |. 83DA 00 sbb edx, 0
00405669 |. 83CF 01 or edi, 1
0040566C |> 09C9 or ecx, ecx
0040566E |. 79 07 jns short 00405677
00405670 |. F7D9 neg ecx
00405672 |. F7DB neg ebx
00405674 |. 83D9 00 sbb ecx, 0
00405677 |> 89CD mov ebp, ecx
00405679 |. B9 40000000 mov ecx, 40
0040567E |. 57 push edi
0040567F |. 31FF xor edi, edi
00405681 |. 31F6 xor esi, esi
00405683 |> D1E0 /shl eax, 1
00405685 |. D1D2 |rcl edx, 1
00405687 |. D1D6 |rcl esi, 1
00405689 |. D1D7 |rcl edi, 1
0040568B |. 39EF |cmp edi, ebp
0040568D |. 72 0B |jb short 0040569A
0040568F |. 77 04 |ja short 00405695
00405691 |. 39DE |cmp esi, ebx
00405693 |. 72 05 |jb short 0040569A
00405695 |> 29DE |sub esi, ebx
00405697 |. 19EF |sbb edi, ebp
00405699 |. 40 |inc eax
0040569A |>^ E2 E7 \loopd short 00405683
0040569C |. 89F0 mov eax, esi
0040569E |. 89FA mov edx, edi
004056A0 |. 5B pop ebx
004056A1 |. F7C3 01000000 test ebx, 1
004056A7 |. 74 07 je short 004056B0
004056A9 |. F7DA neg edx
004056AB |. F7D8 neg eax
004056AD |. 83DA 00 sbb edx, 0
004056B0 |> 5F pop edi
004056B1 |. 5E pop esi
004056B2 |. 5B pop ebx
004056B3 |. 5D pop ebp
004056B4 |. C2 0800 retn 8
004056B7 |> F7F3 div ebx
004056B9 |. 92 xchg eax, edx
004056BA |. 31D2 xor edx, edx
004056BC \.^ EB F2 jmp short 004056B0
004056BE . C3 retn
[课程]Android-CTF解题方法汇总！
