CSCAMP CTF 2012 - Crypto 400

This is the solution script:

import re, requests, string

def main():
print "Solver for CScamp Crypto 400"
print "by amonn"

print "Decomposing raw crypto data..."
parsed = parse_raw()
print "Parsed data: %s." % "".join(i + ", " for i in parsed)[:-2]

print "Working on grabbing keys using lowercase alpha set..."
keyset = build_key()
print "Keys retrieved."

print "Decrypting parsed data with keyset..."
print "Decrypted key is %s." % decrypt(parsed, keyset).upper() # the key is
required in uppercase

def decrypt(parsed, key_dict):
decrypt = ""
for i in parsed:
    decrypt += key_dict[i]
    return decrypt

    def build_key():

    def request_key(letter):
    url = "http://176.9.193.13/CrYpt0ch4l12554222426.php"
    payload = {'key': letter}
    r = requests.get(url, params=payload)
    p = re.compile("([01]{2})
    ([01]{2})
    ([01]{2})

    ")
    s = p.search(r.text)
    if s:
        key = "".join(i for i in s.groups()).encode("ascii", "ignore")
        print "%s: %s" % (letter, key)
        return key
        else:
            return None

            key_dict = {}
            for i in string.ascii_lowercase:
                key_dict[request_key(i)] = i

                return key_dict

                def parse_raw():
                raw_search=["011001011001111010101010011111111110111101101110111010",
                "110010110010000010101010100101010011011011011100000101",
                "001110100010100010100010001000110010111010100000100011"
                ]

# Assuming that there is no sequential rule for each character, we simply
# extract the bits of a specific encoded letter through this scheme:
# 01
# 23
# 45

the_list = []
for i in raw_search:
    em = [h+k for h,k in zip(i[0::2], i[1::2])]
    for j in range(len(em)):
        if len(the_list) < j + 1: the_list.append("")
            the_list[j] += em[j]

            return the_list

if __name__ == "__main__":
    main()