flag = "w3lc0m3_70_345yc7f"
alphabet = "abcdefghijklmnopqrstuvwxyz"
def get_problem(random):
n = random.randint(1, 25)
salt = "".join([random.choice("0123456789abcdef") for i in range(6)])
return (n, salt)
def generate(random):
n, salt = get_problem(random)
trans = str.maketrans(alphabet, alphabet[n:] + alphabet[:n])
ciphertext = ("easyctf{%s}" % "{}_{}".format(flag, salt)).translate(trans)
return dict(variables=dict(
ciphertext=ciphertext
))
def grade(random, key):
_, salt = get_problem(random)
if(key.find("{}_{}".format(flag, salt)) != -1):
return True, "Great! We hope you enjoy the competition."
return False, "Try again."
