Bring-the-Noise( crypto 200 ) Insomnihack teaser CTF 2016

bringTheNoise.py

#amn3s1a team: soez, n4x

from amnesia import *
import hashlib
import itertools

def learn_with_vibrations(lista):
	q, n, eqs = 8, 6, 40
	num = "01234567"
	l = itertools.product(num, repeat=6)
	while True:
		c = "".join(l.next())
		solution = []
		for j in c:
			solution.append(j)
		print "[*] possible solution: %s" % solution
		cont = 0
		for coefs in lista:
			ultimo = int(coefs[len(coefs)-1])	
			for k in range(-1, 3):
				result = sum([int(solution[i])*int(coefs[i]) for i in range(n)]) % q
				vibration = k
				result = (result + q + vibration) % q	
				if result == ultimo:
					cont += 1
					break
		if cont == eqs:
			break
	return solution

s = amnesiaSocket("bringthenoise.insomnihack.ch", 1111)
val = s.readLine()[-6:-1]
print "[*] finding appropitate seed for " + val

for i in range(0xffffff):
    hash_object = hashlib.md5(str(i)).hexdigest()
    if hash_object[:5] == val:
	      print "[+] coincidence founded : %d " % i
	      s.writeLine(str(i))
	      break

lista = []
for i in range(40):
	e = s.readLine()[:-1].split(", ")
	lista.append(e)

solution = learn_with_vibrations(lista)
string = ""
for j in solution:
	string += j + ", "
print "[+] Solution: %s" % string[:-2]
print "[+] Aqui va el flag :)"
print s.readLine()
s.writeLine(string[:-2])
print s.readLine()