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| from z3 import*
apple = 1
banana = 1
cherry = 1
s = Solver()
data = [0x00000010, 0x00000000, 0x00000008, 0x00000014, 0x0000000E, 0x0000000C, 0x00000012, 0x00000002, 0x00000016, 0x0000000A, 0x00000006, 0x00000004]
flag = [BitVec('%d' % i,32)for i in range(24)]
for i in range(24):
s.add(flag[i] <127)
s.add(flag[i] >=32)
def calc_1(x):
return ((x << 4) | (x >> 4))
def calc_2(x, y):
return ((x ^ y) & 0xff)
def calc_3(x, y):
return ((x & 0x55) | ((y & 0xaa) >> 1))
def calc_4(x, y):
return (((x * y) % 1257) & 0xff)
def calc_5(x):
return ((x << 1) | (x >> 7))
def calc_6(x):
return ((x << 3) ^ (x >> 5))
def calc_7(x, y):
return ((x << 4) ^ y)
def func_1(a, b, c, d):
return calc_1(calc_4(calc_5(calc_1(calc_3(calc_5(calc_2(a,b)),calc_5(calc_2(c,d))))),b))
def func_2(a, b):
return calc_5(calc_1(calc_2(a,b)))
def func_3(a, b):
return calc_7(b,calc_1(calc_2(a,b)))
def func_4(a, b):
return (a ^ b)
def check_a(a,b):
global apple
s.add(calc_4(calc_5(calc_1(a)),apple) == b)
apple += 1
def check_b(a,b):
global banana
s.add(calc_5(calc_1(a)) == b)
banana += 1
def check_c(a,b):
global cherry
s.add(calc_6(a) == b)
cherry += 1
if __name__ == '__main__':
input_len = 24
array_1st = [0] * 6
array_2nd = [0] * 6
array_3rd = [0] * 12
for i in range(0, input_len, 4):
if i < 12:
array_3rd[data[i + 3] // 2] = func_2(flag[data[i + 3]], flag[data[i + 3] + 1])
array_1st[i // 4] = func_4(func_3(flag[i * 2], flag[i * 2 + 2]), func_3(flag[i * 2 + 4], flag[i * 2 + 6]))
if i < 4:
array_2nd[i // 4] = func_1(flag[i], flag[i + 4], flag[i + 8], flag[i + 12])
array_1st[(i // 4) + 3] = func_4(func_3(flag[i * 2 + 1], flag[i * 2 + 3]), func_3(flag[i * 2 +5], flag[i *2+7]))
array_3rd[data[i+1]//2]=func_2(flag[data[i+1]],flag[data[i+1]+1])
array_3rd[data[i+2]//2]=func_2(flag[data[i+2]],flag[data[i+2]+1])
if i==4:
array_2nd[1]=func_1(flag[16],flag[20],flag[1],flag[5])
array_3rd[data[i]//2]=func_2(flag[data[i]],flag[data[i]+1])
else:
if i<16:
array_2nd[i//6]=func_1(flag[i-3],flag[i+1],flag[i+5],flag[i*2-3])
array_2nd[3]=func_1(flag[2],flag[6],flag[10],flag[14])
check_c(array_1st[0],0x202)
check_c(array_1st[1],0x1aa2)
check_c(array_1st[2],0x5a5)
array_2nd[4]=func_1(flag[cherry*2-apple-banana],flag[cherry*2+apple+banana],flag[apple*3],flag[banana*7])
array_2nd[5]=func_1(flag[cherry+apple],flag[cherry+5],flag[cherry*2-banana],flag[cherry*2+3])
check_a(array_2nd[0],0x5B)
check_a(array_2nd[1],0xD)
check_a(array_2nd[2],0x5D)
check_a(array_2nd[3],0XA4)
check_a(array_2nd[4],0X34)
check_a(array_2nd[5],0xDC)
check_b(array_3rd[0],0x1010)
check_b(array_3rd[1],0x2828)
check_b(array_3rd[2],0x3838)
check_b(array_3rd[3],0x7070)
check_b(array_3rd[4],0x12d2d)
check_b(array_3rd[5],0x10d0d)
check_b(array_3rd[6],0x4444)
check_b(array_3rd[7],0x1414)
check_b(array_3rd[8],0xc4c4)
check_b(array_3rd[9],0xDCDC)
check_b(array_3rd[10],0x16161)
check_b(array_3rd[11],0x17171)
check_b(func_2(flag[20],flag[23]),0x1010)
check_b(func_2(flag[14],flag[0]),0x16161)
check_c(array_1st[3],0x70F)
check_c(array_1st[4],0x3787)
check_c(array_1st[5],0x3111)
check = 0
for i in range(input_len):
check = (check * 251) ^ flag[i]
s.add(apple == 7)
s.add(banana == 15)
s.add(cherry == 13)
s.add(check == 0x4E6F76D0)
print(s.check())
if(s.check() == sat):
fin = s.model()
print(''.join([chr(fin[x].as_long()) for x in flag]))
else:
print("no ans")
|
