CryptoChat P2P NSA Proof Chat Client

#!/usr/bin/python
# -*- coding: utf-8 -*-
#-------------------------------------------------------------------------------
# Name:        CryptoChat
# Purpose:     Secure P2P chat client
# Notes:       Encrypted with XOR + AES + base64
#              custom chat protocol
#
# Author:      Freak @ PopulusControl (aka sudoer)
#
# Created:     21/02/2015
# Last update: 14/07/2015
#
# Copyright:   (c) Freak 2015
# Licence:     GPLv3
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation, either version 3 of the License, or
#    (at your option) any later version.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
#-------------------------------------------------------------------------------
import sys
import socket
import base64
import random
import string
import hashlib
from Crypto.Cipher import AES
from Crypto import Random
from threading import Thread
import getpass
class CryptoClient():
    def __init__(self):
        print "Welcome to CryptoChat, a secure P2P chat client coded by Freak"
        print "if you dont know what your doing read the README.md!!!"
        self.IP = raw_input("Please enter the IP address you wish to chat with: ")
        self.PORT = int(raw_input("Enter the port for communication: "))
        print
        print "Now enter the keys for the different encryption methods, make sure they are different."
        print "Please note they will note be printed for your security."
        print
        self.EncryptKeyXOR = getpass.getpass("Enter desired key for XOR encryption: ")
        self.EncryptKeyAES = hashlib.md5(getpass.getpass("Enter a secure passphrase for AES: ")).hexdigest()
        print
        raw_input("Press enter when both clients are ready.")
        ###Shit for AES padding
        BS = 16
        self.pad = lambda s: s + (BS - len(s) % BS) * chr(BS - len(s) % BS)
        self.unpad = lambda s : s[:-ord(s[len(s)-1:])]
        ###Start chat server and client
        try:
            Thread(target=self.RecvMSG, args=()).start()
        except:
            print self.IP + " is not ready! Press enter when " + self.IP + " is ready."
            raw_input()
            Thread(target=self.RecvMSG, args=()).start()
        self.SendMSG()
    def EncryptAES(self,raw):
        raw = self.pad(raw)
        iv = Random.new().read( AES.block_size )
        cipher = AES.new( self.EncryptKeyAES, AES.MODE_CBC, iv )
        return base64.b64encode( iv + cipher.encrypt( raw ) )
    def DecryptAES(self,enc):
        enc = base64.b64decode(enc)
        iv = enc[:16]
        cipher = AES.new(self.EncryptKeyAES, AES.MODE_CBC, iv )
        return self.unpad(cipher.decrypt( enc[16:] ))
    def XOR(self,securekey,data,mode):
        if mode == 1:
            securekey=securekey[::-1]
        temp=''
        for char in securekey:
            for x in data:
                temp += chr(ord(x)^ord(char))
            data=temp
            temp=''
        return data
    def EncryptMSG(self,data):
        data = self.XOR(self.EncryptKeyXOR,data,0)
        data = self.EncryptAES(data)
        return data
    def DecryptMSG(self,data):
        data = self.DecryptAES(data)
        data = self.XOR(self.EncryptKeyXOR,data,1)
        return data
    def SendMSG(self):
        clientsock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) # UDP
        print
        print "You are now talking to '"+self.IP+"'"
        while 1:
            message = raw_input("")
            if message.startswith("/send"): #send file command
                self.SendFILE(message.split(" ")[1])
                continue
            if message=="/leave":
                message = self.EncryptMSG("\x03")
                clientsock.sendto(message, (self.IP, self.PORT))
                sys.exit(0)
            if message.startswith("/msg"):
                self.IP=message.split(" ")[1]
                print "[CLIENT] You are now talking to '"+self.IP+"'"
                continue
            else:
                message = self.EncryptMSG("\x01"+message)
                clientsock.sendto(message, (self.IP, self.PORT))
    def SendFILE(self,file_):
        if file_.startswith(".") or file_.startswith("/"): #added security measure.
            print "[CLIENT] For security and safety reasons, filenames starting with '.' or '/' will not be sent. Aborting."
        else:
            clientsock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) # UDP
            data="\x02"+file_+"\xFF"
            f=open(file_,"rb")
            data+=f.read()
            f.close()
            data = self.EncryptMSG(data)
            clientsock.sendto(data, (self.IP, self.PORT))
            print "[CLIENT] File Sent!"
    def RandStr(self,length):
        return ''.join(random.choice(string.letters) for _ in range(length))
    def RecvMSG(self):
        serversocket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) #UDP
        serversocket.bind(('', self.PORT))
        while 1:
            (data, addr) = serversocket.recvfrom(1073741824) # buffer size is 1 gbit (for large files/images)
            data = self.DecryptMSG(data)
            if data.startswith("\x02"):
                filename=''
                data=list(data)
                del data[0]
                for i in data:
                    if i=="\xFF":
                        break
                    else:
                        filename += i
                del data[0] # delete protocol char
                del data[:len(filename)] # delete file end char
                if filename.startswith(".") or filename.startswith("/"): #attempted exploit!
                    print "[!!!ALERT!!!] "+addr[0] + " has attempted to overwrite your " + filename
                else:
                    print "[CLIENT] " + addr[0] + " has sent " + filename
                    print "[CLIENT] Downloading..." #download dat shit
                    data=''.join(data)
                    f = open(filename,"wb")
                    f.write(data)
                    f.close()
                    print "[CLIENT] Saved."
            elif data.startswith("\x01"): # all messages start with "\x01" to prevent file spamming
                data=list(data)
                del data[0]
                data=''.join(data)
                print "["+addr[0]+"] >  |   "+data
            elif data.startswith("\x03"):
                print "[CLIENT] "+addr[0]+" has left."
                sys.exit(0)

if __name__=="__main__":
    CryptoClient()