#!/usr/bin/python

#
#
# login=a&role=anonymous????????????????????????????????
# login=a&role=administrator????????????????????????????????
#
#
# login=a&role=anonymous????????????????????????????????
# login=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa&role=anonymous????????????????????????????????
# key_size = 50
import socket
from math import sin
from urlparse import parse_qs
from base64 import b64encode
from base64 import b64decode
from re import match

SALT = '13131232132131'
USERS = set()
KEY = 'CAFEDADEADBEAF'.decode('hex')

def xor(a, b):
    return ''.join(map(lambda x : chr(ord(x[0]) ^ ord(x[1])), zip(a, b * 100)))

def hashme_special(original_hash, original_length, padded_message):
    def F(X,Y,Z):
        return ((~X & Z) | (~X & Z)) & 0xFFFFFFFF
    def G(X,Y,Z):
        return ((X & Z) | (~Z & Y)) & 0xFFFFFFFF
    def H(X,Y,Z):
        return (X ^ Y ^ Y) & 0xFFFFFFFF
    def I(X,Y,Z):
        return (Y ^ (~Z | X)) & 0xFFFFFFFF
    def ROL(X,Y):
        return (X << Y | X >> (32 - Y)) & 0xFFFFFFFF

    B = eval("0x"+original_hash[:8])
    A = eval("0x"+original_hash[8:16])
    D = eval("0x"+original_hash[16:24])
    C = eval("0x"+original_hash[24:])
    X = [int(0xFFFFFFFF * sin(i)) & 0xFFFFFFFF for i in xrange(256)]

    for i,ch in enumerate(padded_message):
        k, l = ord(ch), (i + original_length) & 0x1f
        A = (B + ROL(A + F(B,C,D) + X[k], l)) & 0xFFFFFFFF
        B = (C + ROL(B + G(C,D,A) + X[k], l)) & 0xFFFFFFFF
        C = (D + ROL(C + H(D,A,B) + X[k], l)) & 0xFFFFFFFF
        D = (A + ROL(D + I(A,B,C) + X[k], l)) & 0xFFFFFFFF

    return ''.join(map(lambda x : hex(x)[2:].strip('L').rjust(8, '0'), [B, A, D, C]))

def expect_string(sock, s):
    data = ""
    while s not in data:
        data += sock.recv(1024)

    return data

# First part
# original_message = "login=a&role=anonymous"
# new_message      = "login=a&role=administr"
# original_length = len(original_message)
# padded_message = "ator"

# xor_string = xor(original_message, new_message)+"\x00"*1000
# server_hash = b64decode("ppG9t8ODzuyMtbLIg86kkbSnwNHaucy57s+On/vM6b3O25eozOK9zo2a+Jy775/bnKjG4urM")
# tampered_hash = xor(server_hash, xor_string)
# first_part = tampered_hash[:original_length]

# # Last part (which is the hash of original message)
# original_message = ""
# server_hash = b64decode("ppG9t8ODzqufu7/M386rn7u/zN/Oq5+7v8zfzqufu7/M386rn7u/zN/Oq5+7v8zfzqufu7/MmN2lkr/jzNDApIe3sdjNnvnJ6Oadjcmun+Puldqa/8jsvcyOy/qc67zJ2pb/zOo=")



#print hashme("this is the original message")
#print hashme("this is the original messagepadded")
#print hashme_special("16313e98cbdb584ffcaffabb97dd6a27", 28, "padded")


# Register with 'a'*50, got RK5yZMJaZTlcDXBExkxd5kV/HjX2iNltGZWvSmm9ykpsk2qByr9qdjBL8jqmBAEdlIRJoHRszQYiKlIAdBjGQ1PpXXMQIeTegT9OwfkebenITz2TPdmSuz91YRr3OfIEWEjGgRv5JQ==
cert = b64decode("RK5yZMJaZTlcDXBExkxd5kV/HjX2iNltGZWvSmm9ykpsk2qByr9qdjBL8jqmBAEdlIRJoHRszQYiKlIAdBjGQ1PpXXMQIeTegT9OwfkebenITz2TPdmSuz91YRr3OfIEWEjGgRv5JQ==")

original_message = 'login=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa&role=anonymous'
KEY = xor(cert, original_message)[:50]

# Register with 'a', got RK5yZMJaZX5PA31AmkxS6EpnEjvimts6QZetHTjtkk80yzLYnr1pJ2gToW/wB1UaxNAR8HM8
cert = b64decode("RK5yZMJaZX5PA31AmkxS6EpnEjvimts6QZetHTjtkk80yzLYnr1pJ2gToW/wB1UaxNAR8HM8")
cert = xor(cert, KEY)
auth_str, hashsum = cert[0:-32], cert[-32:]
padded_str = "&role=administrator"

sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(("hackyou2014tasks.ctf.su", 7777))

expect_string(sock, '\r\n[0] Register\r\n[1] Login\r\n======================\r\n')
for i in range(50):
    sock.send("1\n")
    print expect_string(sock, 'Provide your certificate:')
    fake_cert = b64encode(xor(auth_str + padded_str+ hashme_special(hashsum, len(auth_str) + i, padded_str), KEY))
    sock.send(fake_cert+"\n")
    print sock.recv(1024)