hybrid-file-crypto.ipynb

{
 "cells": [
  {
   "cell_type": "code",
   "execution_count": 12,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "File Encryption Complete!\n"
     ]
    }
   ],
   "source": [
    "from Crypto.Cipher import Blowfish, PKCS1_OAEP, AES\n",
    "from Crypto.PublicKey import RSA\n",
    "from Crypto.Util.Padding import pad, unpad\n",
    "from binascii import hexlify , unhexlify\n",
    "import hashlib , json, string, random\n",
    "from stegano import lsb\n",
    "from datetime import datetime\n",
    "\n",
    "# Key Generator\n",
    "def key_generator(size, case=\"default\", punctuations=\"required\"):\n",
    "    if case==\"default\" and punctuations==\"required\":\n",
    "        return ''.join(random.choices(string.ascii_uppercase + string.ascii_lowercase + string.digits + string.punctuation, k = size))\n",
    "    elif case==\"upper-case-only\" and punctuations==\"required\":\n",
    "        return ''.join(random.choices(string.ascii_uppercase + string.digits + string.punctuation, k = size))\n",
    "    elif case==\"lower-case-only\"  and punctuations==\"required\":\n",
    "        return ''.join(random.choices(string.ascii_lowercase + string.digits + string.punctuation, k = size))\n",
    "    elif case==\"default\" and punctuations==\"none\":\n",
    "        return ''.join(random.choices(string.ascii_uppercase + string.digits + string.ascii_lowercase, k = size))\n",
    "    elif case==\"lower-case-only\"  and punctuations==\"none\":\n",
    "        return ''.join(random.choices(string.ascii_lowercase + string.digits , k = size))\n",
    "    elif case==\"upper-case-only\" and punctuations==\"none\":\n",
    "        return ''.join(random.choices(string.ascii_uppercase + string.digits, k = size))\n",
    "    \n",
    "# Plaintext Input\n",
    "with open('./test_files/testdoc006.jpg', 'rb') as file:\n",
    "    plaintext = file.read()\n",
    "    \n",
    "\n",
    "log_plaintext_length = len(hexlify(plaintext))\n",
    "\n",
    "# Password for Keys\n",
    "password = 'srm2017' #input('Enter Password: ')\n",
    "log_password_length = len(password)\n",
    "\n",
    "log_start_time = datetime.now()\n",
    "\n",
    "hash = hashlib.sha1()\n",
    "hash.update(password.encode())\n",
    "password_encryption_cipher = AES.new( hash.hexdigest()[:16].encode() , AES.MODE_CBC, iv= '16bitAESInitVect'.encode())\n",
    "\n",
    "# Dictionary of Keys\n",
    "keys_iv = {}\n",
    "\n",
    "# Blowfish Layer 1\n",
    "\n",
    "blowfish_key =  key_generator(size=16).encode()\n",
    "blowfish_cipher = Blowfish.new(blowfish_key, Blowfish.MODE_CBC)\n",
    "\n",
    "blowfish_ciphertext = blowfish_cipher.encrypt(pad(plaintext, Blowfish.block_size ))\n",
    "\n",
    "keys_iv['blowfish_iv'] = hexlify(blowfish_cipher.iv).decode()\n",
    "keys_iv['blowfish_key'] = hexlify(blowfish_key).decode()\n",
    "\n",
    "# RSA Layer 2\n",
    "\n",
    "rsa_key = RSA.generate(2048)\n",
    "rsa_private_key = rsa_key\n",
    "rsa_public_key = rsa_key.publickey()\n",
    "\n",
    "cipher_rsa = PKCS1_OAEP.new(rsa_public_key)\n",
    "rsa_plaintext = blowfish_ciphertext\n",
    "\n",
    "rsa_ciphertext = bytearray()\n",
    "for i in range(0, len(rsa_plaintext), 190):\n",
    "    rsa_ciphertext.extend(cipher_rsa.encrypt(rsa_plaintext[i:i+190]))\n",
    "\n",
    "keys_iv['rsa_n'] = rsa_private_key.n\n",
    "keys_iv['rsa_e'] = rsa_private_key.e\n",
    "keys_iv['rsa_d'] = rsa_private_key.d\n",
    "\n",
    "# AES Layer 3\n",
    "aes_key =  key_generator(size=16).encode()\n",
    "aes_cipher = AES.new(aes_key, AES.MODE_CBC)\n",
    "aes_plaintext = rsa_ciphertext\n",
    "\n",
    "aes_ciphertext = aes_cipher.encrypt(pad(aes_plaintext, AES.block_size))\n",
    "\n",
    "ciphertext = aes_ciphertext\n",
    "\n",
    "with open('./test_files/testdoc006_hyenc.encrypted', 'w') as file:\n",
    "    file.write(hexlify(ciphertext).decode())\n",
    "\n",
    "log_ciphertext_length = len(hexlify(ciphertext))\n",
    "\n",
    "keys_iv['aes_iv'] = hexlify(aes_cipher.iv).decode()\n",
    "keys_iv['aes_key'] = hexlify(aes_key).decode()\n",
    "\n",
    "\n",
    "# Encryption of Key and IV String\n",
    "encrypted_keys_and_iv = hexlify(password_encryption_cipher.encrypt(pad(json.dumps(keys_iv).encode(), AES.block_size)))\n",
    "\n",
    "#LSB Steg\n",
    "lsb_stegano_image = lsb.hide(\"./cover_image.png\", encrypted_keys_and_iv.decode())\n",
    "lsb_stegano_image.save(\"./stego_image.png\") \n",
    "\n",
    "log_end_time = datetime.now()\n",
    "\n",
    "log_duration = str(log_end_time - log_start_time)\n",
    "\n",
    "with open('./logs/encryption-log.txt', 'a+') as log_file:\n",
    "    log_file.write( \"\\n| \"   +str(log_plaintext_length)\n",
    "                   +\"          | \"+str(log_ciphertext_length)\n",
    "                   +\"          | \"+str(log_password_length)\n",
    "                   +\"         | \"+log_start_time.strftime(\"%H:%M:%S\")\n",
    "                   +\"   | \"+log_end_time.strftime(\"%H:%M:%S\")\n",
    "                   +\"  | \"+str(log_duration)\n",
    "                   +\" |\"\n",
    "                  )\n",
    "    \n",
    "print('File Encryption Complete!')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 13,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "File Decryption Complete!\n"
     ]
    }
   ],
   "source": [
    "# Password for Keys\n",
    "password = 'srm2017' #input('Enter Password: ')\n",
    "\n",
    "with open('./test_files/testdoc006_hyenc.encrypted', 'r') as file:\n",
    "    ciphertext = file.read()\n",
    "\n",
    "log_password_length = len(password)\n",
    "log_ciphertext_length = len(ciphertext)\n",
    "\n",
    "log_start_time = datetime.now()\n",
    "\n",
    "# LSB Steg\n",
    "unhide_encrypted_keys_and_iv = lsb.reveal(\"./stego_image.png\").encode()\n",
    "\n",
    "hash = hashlib.sha1()\n",
    "hash.update(password.encode())\n",
    "password_decryption_cipher = AES.new( hash.hexdigest()[:16].encode() , AES.MODE_CBC, iv= '16bitAESInitVect'.encode())\n",
    "\n",
    "decrypted_keys_iv = json.loads(unpad(password_decryption_cipher.decrypt(unhexlify(unhide_encrypted_keys_and_iv)), AES.block_size))\n",
    "\n",
    "#Initializations\n",
    "decryption_key_aes = unhexlify(decrypted_keys_iv['aes_key'])\n",
    "decryption_iv_aes = unhexlify(decrypted_keys_iv['aes_iv'])\n",
    "decryption_key_rsa = RSA.construct(rsa_components = (decrypted_keys_iv['rsa_n'] , decrypted_keys_iv['rsa_e'] , decrypted_keys_iv['rsa_d']))\n",
    "decryption_iv_blowfish = unhexlify(decrypted_keys_iv['blowfish_iv'])\n",
    "decryption_key_blowfish = unhexlify(decrypted_keys_iv['blowfish_key'])\n",
    "\n",
    "\n",
    "aes_cipher_decryption = AES.new(decryption_key_aes, AES.MODE_CBC, iv=decryption_iv_aes)\n",
    "rsa_cipher_decryption = PKCS1_OAEP.new(decryption_key_rsa)\n",
    "blowfish_cipher_decryption = Blowfish.new(decryption_key_blowfish, Blowfish.MODE_CBC, iv=decryption_iv_blowfish)\n",
    "\n",
    "# AES DECRYPTION\n",
    "ciphertext_rsa = unpad(aes_cipher_decryption.decrypt(unhexlify(ciphertext)), AES.block_size)\n",
    "# RSA DECRYPTION\n",
    "ciphertext_blowfish = bytearray()\n",
    "for i in range(0, len(ciphertext_rsa),256):\n",
    "    ciphertext_rsa_segment = ciphertext_rsa[i:i+256]\n",
    "    ciphertext_blowfish.extend(rsa_cipher_decryption.decrypt(ciphertext_rsa_segment))\n",
    "    \n",
    "# BLOWFISH DECRYPTION\n",
    "decrypted_plaintext = unpad(blowfish_cipher_decryption.decrypt(ciphertext_blowfish), Blowfish.block_size)\n",
    "\n",
    "log_end_time = datetime.now()\n",
    "log_duration = str(log_end_time - log_start_time)\n",
    "log_plaintext_length = len(hexlify(decrypted_plaintext))\n",
    "\n",
    "with open('./logs/decryption-log.txt', 'a+') as log_file:\n",
    "    log_file.write( \"\\n| \"   +str(log_ciphertext_length)\n",
    "                   +\"          | \"+str(log_plaintext_length)\n",
    "                   +\"          | \"+str(log_password_length)\n",
    "                   +\"         | \"+log_start_time.strftime(\"%H:%M:%S\")\n",
    "                   +\"   | \"+log_end_time.strftime(\"%H:%M:%S\")\n",
    "                   +\"  | \"+str(log_duration)\n",
    "                   +\" |\"\n",
    "                  )\n",
    "\n",
    "with open('./test_files/testdoc006_hydec.jpg', 'wb') as file:\n",
    "    file.write(decrypted_plaintext)\n",
    "    \n",
    "#print(\"Decrypted Ciphertext: \", decrypted_plaintext.decode())\n",
    "print('File Decryption Complete!')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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