client

import os
import socket
import threading
import select
import sys
import re

from comms import send, receive

from Crypto.PublicKey import RSA
from Crypto.Signature import PKCS1_PSS
from Crypto.Hash import SHA

exiting = False


def recv_loop(connection):
    while True:
        if exiting:
            print "Ending receive loop"
            return
        (readable, writable, errored) = select.select([connection], [], [connection], 0.1)
        if readable or errored:
            #message = connection.recv(1024)
            message = receive(connection)
            if not message:
                print "*** Disconnected from server ***"
                break
            else:
                if 'PLAIN' in message:
                    message = message.strip('PLAIN').strip()
                else:
                    message = decryptor.decrypt(message)
                print message


sckt = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
host = '127.0.0.1'
port = '5000'

#host = raw_input('Entra la IP del servidor >')
while not re.match(r"^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$",host):
    print ("Error! Segur que has escrit be la IP?")
    host = raw_input('Entra la IP del servidor >')
#port = raw_input('Entra el port del servidor >')
while not re.match(r"^[0-9]+$",port):
    print ("Error! Segur que has escrit be el port?")
    port = raw_input('Entra el port del servidor >')

try:
    print "Connecting to server..."

    client_privkey = RSA.generate(1024, os.urandom)
    client_pubkey = client_privkey.publickey()

    decryptor = client_privkey

    sckt.connect( (host, int(port)) )
#    sckt.send(client_pubkey.exportKey())
    send(sckt, client_pubkey.exportKey())
#    server_pubkey = sckt.recv(1024)
    server_pubkey = receive(sckt)
    encryptor = RSA.importKey(server_pubkey)
except socket.error:
    print 'No hem pogut establir connexio amb el servidor @ %s' % ('%s:%s' % sckt.getsockname())
    sys.exit(1)



print "Connectat! Tecleja l'ordre /help per veure la llista d'ordres"
print "== Introdueix el nom d'usuari: "


threading.Thread(target=recv_loop, args=[sckt]).start()

while True:
    message = raw_input()
    if message.lower() == '/exit':
        exiting = True
        sys.exit(0)
    else:
        try:
            #encrypt
            message = encryptor.encrypt(message, 0)
            message = message[0]

            #append client signature
            signkey = decryptor
            message_hash = SHA.new()
            message_hash.update(message)

            signer = PKCS1_PSS.new(signkey)
            signature = signer.sign(message_hash)
            message = '%s#^[[%s' % (message, signature)

        except ValueError:
            print 'Massa text, no s\'ha pogut encriptar ni enviar'
            message = None

        if message:
            #sckt.send(message)
            send(sckt, message)