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| import struct
from z3 import *
def exec(cin, a2):
start = False
v2 = buf[0]
if v2 < a2:
while True:
if (start):
buf[0] += 3
v2 = buf[0]
if (buf[0] >= a2):
break
if (not start):
start = True
for m in range(0, 3):
vm_body[m] &= 0xff
v6 = cin[v2]
v7 = cin[v2+1]
v8 = cin[v2+1]
v9 = cin[v2+2]
v10 = v9
if v6 == 0:
v11 = vm_body[v8]
vm_body[v8] = vm_body[v10]
vm_body[v10] = v11
elif v6 == 1:vm_body[v8] ^= vm_body[v9]
elif v6 == 2:vm_body[v8] += v9
elif v6 == 3:vm_body[v8] += vm_body[v9]
elif v6 == 4:vm_body[v8] -= v9
elif v6 == 5:vm_body[v8] -= vm_body[v9]
elif v6 == 6:vm_body[v8] *= v9
elif v6 == 7:vm_body[v8] *= vm_body[v9]
elif v6 == 8:vm_body[v8] = vm_body[v8] / v9
elif v6 == 9:vm_body[v8] = vm_body[v8] / vm_body[v9]
elif v6 == 10: vm_body[v8] = vm_body[v8] % v9
elif v6 == 11:vm_body[v8] = vm_body[v8] % vm_body[v9]
elif v6 == 12:
v12 = vm_body[v8]
vm_body[v8] = v12 << v9
elif v6 == 13:
v12 = vm_body[0]
vm_body[v8] = v12 << v9
elif v6 == 14:
v15 = vm_body[v8]
vm_body[buf[1] + 16] = v15
buf[1] += 1
elif v6 == 15:v13 = vm_body[v8]
elif v6 == 16:
v14 = buf[1] - 1
buf[1] -= 1
v13 = vm_body[v14 + 16]
elif v6 == 17:
if not vm_body[v8]:
buf[0] = v9
elif v6 == 18:
if vm_body[v8]:
buf[0] = v9
elif v6 == 19:
buf[0] = v7
elif v6 == 20:
v8 = vm_body[v8]
v15 = vm_body[v8]
vm_body[buf[1] + 16] = v15
buf[1] += 1
elif v6 == 21:
v16 = buf[1] - 1
buf[1] -= 1
vm_body[0] = vm_body[v16 + 16]
elif v6 == 22:
v15 = v7
vm_body[buf[1] + 16] = v15
buf[1] += 1
elif v6 == 23:
buf[0] -= 3
elif v6 == 24:
vm_body[0] = vm_body[2] | vm_body[1]
elif v6 == 25:
vm_body[v8] = vm_body[0] >> v9
elif v6 == 26:
vm_body[v8] = v9
else:
continue
buf[0] = 0
return
enc= [0xDF, 0xD5, 0xF1, 0xD1, 0xFF, 0xDB, 0xA1, 0xA5, 0x89, 0xBD,
0xE9, 0x95, 0xB3, 0x9D, 0xE9, 0xB3, 0x85, 0x99, 0x87, 0xBF,
0xE9, 0xB1, 0x89, 0xE9, 0x91, 0x89, 0x89, 0x8F, 0xAD]
num=[BitVec("num[%d]"%i,32) for i in range(29)]
solver=Solver()
for i in range(29):
vm_body = [0]*0x10
buf=[0]*2
out = [0]*30
vm_body[3:3+4] = 0xBEEDBEEF.to_bytes(4, byteorder="little")
a1 = 0
v2 = i+1
code = [0]*64
while (v2):
v2 -= 1
code[48:48+8] = 0x20D01011903001A.to_bytes(8, byteorder="little")
code[55:55+8] = 0x300010201180702.to_bytes(8, byteorder="little")
code[50] = num[a1]
exec(code[48:], 15)
code[32:32+8] = 0x20D02011903001A.to_bytes(8, byteorder="little")
code[39:39+8] = 0x400010201180602.to_bytes(8, byteorder="little")
code[34] = vm_body[0]
exec(code[32:], 15)
code[16:16+8] = 0x20D03011903001A.to_bytes(8, byteorder="little")
code[23:23+8] = 0x500010201180502.to_bytes(8, byteorder="little")
code[18] = vm_body[0]
exec(code[16:], 15)
code[0:0+8] = 0x20D04011903001A.to_bytes(8, byteorder="little")
code[7:7+8] = 0x600010201180402.to_bytes(8, byteorder="little")
code[2] = vm_body[0]
exec(code, 15)
out[a1] = ((vm_body[0] >> 5) | (vm_body[0] << 3)) & 0xff
a1 += 1
for i in range(29):
solver.add(out[i]==enc[i])
print(solver.check())
flag=[68,65,83,67,84,70,123,121,111,117,95,97,114,101,95,114,105,103,104,116,95,115,111,95,99,111,111,108,125]
for i in flag:
print(chr(i%128),end='')
|
