REdo2

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main:
lea ecx, [esp+4]
and esp, -16
push DWORD PTR [ecx-4]
push ebp
mov ebp, esp
push ebx
push ecx
sub esp, 32
mov ebx, ecx
cmp DWORD PTR [ebx], 2
je .L2
mov eax, 1
jmp .L3
.L2:
mov DWORD PTR [ebp-12], 0
jmp .L4
.L6:
mov eax, DWORD PTR [ebx+4]
add eax, 4
mov edx, DWORD PTR [eax]
mov eax, DWORD PTR [ebp-12]
add eax, edx
movzx eax, BYTE PTR [eax]
test al, al
jne .L5
mov eax, 1
jmp .L3
.L5:
add DWORD PTR [ebp-12], 1
.L4:
cmp DWORD PTR [ebp-12], 28
jle .L6
sub esp, 12
push 29
call malloc #初始化 29 推测密钥长度29
add esp, 16
mov DWORD PTR [ebp-32], eax
mov DWORD PTR [ebp-16], 0
jmp .L7
.L8:
mov eax, DWORD PTR [ebx+4]
add eax, 4
mov edx, DWORD PTR [eax]
mov eax, DWORD PTR [ebp-16]
add eax, edx
mov ecx, DWORD PTR [ebp-16]
mov edx, DWORD PTR [ebp-32]
add edx, ecx
movzx eax, BYTE PTR [eax]
mov BYTE PTR [edx], al
mov edx, DWORD PTR [ebp-16]
mov eax, DWORD PTR [ebp-32]
add eax, edx
movzx eax, BYTE PTR [eax]
lea ecx, [eax-49] #数值减49
mov edx, DWORD PTR [ebp-16]
mov eax, DWORD PTR [ebp-32]
add eax, edx
mov edx, ecx
mov BYTE PTR [eax], dl
add DWORD PTR [ebp-16], 1
.L7:
cmp DWORD PTR [ebp-16], 28
jle .L8
mov eax, DWORD PTR [ebp-32]
movzx edx, BYTE PTR [eax]

mov eax, DWORD PTR [ebp-32] #等同于第0
add eax, 2
; movzx eax, BYTE PTR [eax]
cmp dl, al
je .L9
mov eax, 1
jmp .L3
.L9:
mov eax, DWORD PTR [ebp-32]
add eax, 1
movzx eax, BYTE PTR [eax]#
cmp al, 56 # 8
je .L10
mov eax, 1
jmp .L3
.L10:
mov eax, DWORD PTR [ebp-32]
movzx eax, BYTE PTR [eax]
cmp al, 54 # 6
je .L11
mov eax, 1
jmp .L3
.L11:
mov eax, DWORD PTR [ebp-32]
add eax, 3
movzx eax, BYTE PTR [eax]
cmp al, 52
je .L12
mov eax, 1
jmp .L3
.L12:
mov eax, DWORD PTR [ebp-32]
add eax, 28
movzx eax, BYTE PTR [eax]
movsx eax, al
mov edx, DWORD PTR [ebp-32]
add edx, 5
movzx edx, BYTE PTR [edx]
movsx edx, dl
add edx, 2
cmp eax, edx #第五位和第28位相等
je .L13
mov eax, 1
jmp .L3
.L13:
mov eax, DWORD PTR [ebp-32]
add eax, 5
movzx eax, BYTE PTR [eax]
cmp al, 74
je .L14
mov eax, 1
jmp .L3
.L14:
mov eax, DWORD PTR [ebp-32]
add eax, 4
movzx eax, BYTE PTR [eax]
cmp al, 60
je .L15
mov eax, 1
jmp .L3
.L15:
mov DWORD PTR [ebp-20], 0
jmp .L16
.L18:
mov eax, DWORD PTR [ebp-20]
lea edx, [eax+6]
mov eax, DWORD PTR [ebp-32]
add eax, edx
movzx eax, BYTE PTR [eax]
cmp al, 48
je .L17
mov eax, 1
jmp .L3
.L17:
add DWORD PTR [ebp-20], 1
.L16:
cmp DWORD PTR [ebp-20], 2
jle .L18
mov DWORD PTR [ebp-24], 0
jmp .L19
.L21:
mov eax, DWORD PTR [ebp-24]
lea edx, [eax+10]
mov eax, DWORD PTR [ebp-32]
add eax, edx
movzx eax, BYTE PTR [eax]
cmp al, 49
je .L20
mov eax, 1
jmp .L3
.L20:
add DWORD PTR [ebp-24], 1
.L19:
cmp DWORD PTR [ebp-24], 3
jle .L21
mov DWORD PTR [ebp-28], 0
jmp .L22
.L24:
mov eax, DWORD PTR [ebp-28]
lea edx, [eax+15]
mov eax, DWORD PTR [ebp-32]
add eax, edx
movzx eax, BYTE PTR [eax]
cmp al, 50
je .L23
mov eax, 1
jmp .L3
.L23:
add DWORD PTR [ebp-28], 1
.L22:
cmp DWORD PTR [ebp-28], 4
jle .L24
mov eax, DWORD PTR [ebp-32]
add eax, 21
movzx eax, BYTE PTR [eax]
movsx eax, al
mov edx, DWORD PTR [ebp-32]
add edx, 15
movzx edx, BYTE PTR [edx]
movsx edx, dl
add edx, 1
cmp eax, edx
je .L25
mov eax, 1
jmp .L3
.L25:
mov eax, DWORD PTR [ebp-32]
add eax, 9
movzx edx, BYTE PTR [eax]
mov eax, DWORD PTR [ebp-32]
add eax, 14
movzx eax, BYTE PTR [eax]
cmp dl, al
je .L26
mov eax, 1
jmp .L3
.L26:
mov eax, DWORD PTR [ebp-32]
add eax, 9
movzx edx, BYTE PTR [eax]
mov eax, DWORD PTR [ebp-32]
add eax, 20
movzx eax, BYTE PTR [eax]
cmp dl, al
je .L27
mov eax, 1
jmp .L3
.L27:
mov eax, DWORD PTR [ebp-32]
add eax, 9
movzx edx, BYTE PTR [eax]
mov eax, DWORD PTR [ebp-32]
add eax, 22
movzx eax, BYTE PTR [eax]
cmp dl, al
je .L28
mov eax, 1
jmp .L3
.L28:
mov eax, DWORD PTR [ebp-32]
add eax, 9
movzx eax, BYTE PTR [eax]
cmp al, 46
je .L29
mov eax, 1
jmp .L3
.L29:
mov eax, DWORD PTR [ebp-32]
add eax, 27
movzx eax, BYTE PTR [eax]
cmp al, 1
je .L30
mov eax, 1
jmp .L3
.L30:
mov eax, DWORD PTR [ebp-32]
add eax, 26
movzx eax, BYTE PTR [eax]
cmp al, 2
je .L31
mov eax, 1
jmp .L3
.L31:
mov eax, DWORD PTR [ebp-32]
add eax, 23
movzx eax, BYTE PTR [eax]
cmp al, 3
je .L32
mov eax, 1
jmp .L3
.L32:
mov eax, DWORD PTR [ebp-32]
add eax, 24
movzx eax, BYTE PTR [eax]
cmp al, 4
je .L33
mov eax, 1
jmp .L3
.L33:
mov eax, DWORD PTR [ebp-32]
add eax, 25
movzx eax, BYTE PTR [eax]
movsx eax, al
.L3:
lea esp, [ebp-8]
pop ecx
pop ebx
pop ebp
lea esp, [ecx-4]
ret

整个题目先看数值比较部分,cmp后对应数值和对应偏移

5=J

8=7=6=0

13,12,11,10=1

15,16,17,18,19=2

28=L

15+1=21

9=14=20=22=’.’

得出数据串

6864<J000.1111.22222.3.34021L

在 L8位置有一个数值减去49,加回来就好了

gigem{aaa_bbbb_ccccc_d_45132}