solutions to the net levels of protostar
http://exploit-exercises.com/protostar/net0
import socket, re, struct
HOST = '127.0.0.1'
PORT = 2999
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((HOST, PORT))
# get the welcome message
data = s.recv(1024)
# extract the number an convert it
number = re.findall(r'\'[0-9]*\'',data)[0][1:-1:]
number_int = int(number)
number_pack = struct.pack('l',number_int)
# just some nice prints
print number
print number_int
print number_pack
# send the number back to the server
s.sendall(number_pack)
# check the answer
data = s.recv(1024)
print data
s.close()