Skip to content

075-python-basics-10.md

Latest commit

 

History

History
28 lines (18 loc) · 848 Bytes

075-python-basics-10.md

File metadata and controls

28 lines (18 loc) · 848 Bytes

75 - Python Basics 10

Written by Emily Leng

Problem

args[0] is a result of XOR encryption on two hexadecimal strings. You only know one of the two original strings, args[1], can you find the other?

Clarification: after finding the second string you should print the ascii representation of it as the answer in the Python Editor.

Hint

The operation ^ in python only works on numbers. The built in functions ord() and chr() convert between characters and numbers.

Solution

def xor_strings(xs, ys):
    return "".join(chr(ord(x) ^ ord(y)) for x, y in zip(xs, ys))
a = ''.join([chr(int(''.join(c), 16)) for c in zip(args[0][0::2], args[0][1::2])])
b = ''.join([chr(int(''.join(c), 16)) for c in zip(args[1][0::2], args[1][1::2])])
c = xor_strings(a,b)
print c

Flag

x0r_encrypti0n_is_be_e4sy_t0_crack