sundae
use your python skills to finish making the sundae and get the flag
challenge file:
solution:
we are provided with two challenge files one is an ASCII text which has 1's and 0's and other is a .pyc file which is compiles python byte-code.....
when I tries to run the .pyc file I got something like this
So, seeing this first I tried to find strings in the .pyc file and I found a few
I found few interesting like sugar,Chocolate_ice_cream.... but nothing worked.so I stared to find the source code of the .pyc file
searching around I found this amazing tool online which converts the byte-code to a plain text code....
so using this tool I converted it and volaa!.....
syrup = 4
sauce = [66666, 55555, 44444, 33333]
cream = []
gg = []
mix = []
def cmp(a, b):
return (a > b) - (a < b)
def Whipped_cream(Butter, key):
for i in key:
Butter[3] = (Butter[3] ^ i) - 117
for i in key:
Butter[6] = (Butter[6] ^ i) + 43
for i in key:
Butter[9] = (Butter[9] ^ i) - 99
for i in key:
Butter[12] = (Butter[12] ^ i) - 10
for i in key:
Butter[15] = (Butter[15] ^ i) + 115
for i in key:
Butter[18] = (Butter[18] ^ i) + 75
for i in key:
Butter[21] = (Butter[21] ^ i) - 22
for i in key:
Butter[24] = (Butter[24] ^ i) - 118
for i in key:
Butter[27] = (Butter[27] ^ i) + 38
for i in key:
Butter[30] = (Butter[30] ^ i) + 66
for i in key:
Butter[2] = (Butter[2] ^ i) - 117
for i in key:
Butter[4] = (Butter[4] ^ i) + 43
for i in key:
Butter[8] = (Butter[8] ^ i) - 99
for i in key:
Butter[10] = (Butter[10] ^ i) - 10
for i in key:
Butter[14] = (Butter[14] ^ i) + 115
for i in key:
Butter[16] = (Butter[16] ^ i) + 75
for i in key:
Butter[20] = (Butter[20] ^ i) - 22
for i in key:
Butter[22] = (Butter[22] ^ i) - 118
for i in key:
Butter[26] = (Butter[26] ^ i) + 38
for i in key:
Butter[28] = (Butter[28] ^ i) + 66
return Butter
def Vanilla_Essence():
for i in range(len(sauce)):
mix.append(int(bin(sauce[i])[3:], 2) ^ 7)
return mix
def CoCoAAA(inp):
for i in range(0, len(inp)):
cream.append((ord(inp[i]) & 15) >> 4 | ord(inp[i]) << 4)
gg.append(cream[i] ^ 45)
return gg
def Chocolate_ice_cream(choco, s):
result = []
for i in range(len(choco)):
char = choco[i]
if char.isnumeric():
result.append(chr(ord(char) + 2))
elif char.isupper():
result.append(chr((ord(char) + syrup - 65) % 26 + 65))
elif char.islower():
result.append(chr((ord(char) + syrup - 97) % 26 + 97))
else:
result.append(char)
return result
def main():
flag = 0
sugar = input('Enter ingredient: ')
if len(sugar) < 30:
print 'Did you even check out the code ? lol'
exit()
CHOCOLATE_SUNDAE = Whipped_cream(CoCoAAA(Chocolate_ice_cream(sugar, syrup)), Vanilla_Essence())
bowl = open('book', 'r')
Chocolate_Wafers = bowl.readlines()
for i in range(0, len(CHOCOLATE_SUNDAE)):
if cmp(CHOCOLATE_SUNDAE[i], int(Chocolate_Wafers[i], 2)) == 0:
flag += 1
if flag == 31:
print (
'Good Work ! \nTake your flag : ', sugar)
else:
print 'meh!'
if __name__ == '__main__':
main()
This code is performing several BITWISE &,| and ^(XOR) and comparing it to the one in the book named file which is the other file I was taking about
from this we can say that the length of key is 30 or above:
if len(sugar) < 30:
print 'Did you even check out the code ? lol'
and we need to change a little piece of code like:
def main():
A=[0]*31
flag = 0
for j in range(42,127):
sugar = [chr(j)]*30
CHOCOLATE_SUNDAE = Whipped_cream(CoCoAAA(Chocolate_ice_cream(sugar, syrup)), Vanilla_Essence())
bowl = open('book', 'r')
Chocolate_Wafers = bowl.readlines()
for i in range(0, len(CHOCOLATE_SUNDAE)):
if cmp(CHOCOLATE_SUNDAE[i], int(Chocolate_Wafers[i], 2)) == 0:
A[i]=chr(j)
print(A)
This change will give you the flag
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