Python/cryptography/des_key_generation.ipynb

{
 "cells": [
  {
   "cell_type": "code",
   "execution_count": 1,
   "id": "1057a613",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<style>.container{width:100%}</style>\n"
      ],
      "text/plain": [
       "<IPython.core.display.HTML object>"
      ]
     },
     "metadata": {},
     "output_type": "display_data"
    }
   ],
   "source": [
    "%%HTML\n",
    "<style>.container{width:100%}</style>"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "040e1454",
   "metadata": {},
   "source": [
    "## Key generation for DES for 16 rounds"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "id": "7bd02a30",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "['1B02EFFC7072',\n",
       " '79AED9DBC9E5',\n",
       " '55FC8A42CF99',\n",
       " '72ADD6DB351D',\n",
       " '7CEC07EB53A8',\n",
       " '63A53E507B2F',\n",
       " 'EC84B7F618BC',\n",
       " 'F78A3AC13BFB',\n",
       " 'E0DBEBEDE781',\n",
       " 'B1F347BA464F',\n",
       " '215FD3DED386',\n",
       " '7571F59467E9',\n",
       " '97C5D1FABA41',\n",
       " '5F43B7F2E73A',\n",
       " 'BF918D3D3F0A',\n",
       " 'CB3D8B0E17F5']"
      ]
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "import random\n",
    "def r64():\n",
    "    r64 = ''\n",
    "    for i in range(8):\n",
    "        r = str(bin(random.randint(0,2**8)))[2:]\n",
    "        if(len(r)<8):\n",
    "            r = '0'*(8-len(r)) + r\n",
    "        r64 +=r\n",
    "    return r64\n",
    "def hex2bin(hexa):\n",
    "    binstr = bin(int(hexa,16))[2:]\n",
    "    binstr = binstr.zfill(len(hexa)*4)\n",
    "    return binstr\n",
    "\n",
    "def bin2hex(binary):\n",
    "    binary = binary.zfill(len(binary) +( 4-len(binary)%4)%4)\n",
    "    hexa = hex(int(binary,2))[2:].upper()\n",
    "    return hexa\n",
    "\n",
    "\n",
    "def key_gen(bit64):\n",
    "    bit64 = '#'+bit64\n",
    "    PC_1 = [57,49,41,33, 25,17,9,1,\n",
    "            58,50,42,34, 26,18,10, \n",
    "            2,59,51,43, 35,27,19,11,\n",
    "            3,60,52,44, 36,63,55,47,\n",
    "            39,31,23,15, 7,62,54,46,\n",
    "            38,30,22,14, 6,61,53,45,\n",
    "            37,29,21,13, 5,28,20,12,4]\n",
    "    \n",
    "    PC_2 = [14,17,11,24, 1,5,3,28,\n",
    "            15,6,21,10, 23,19,12,4,\n",
    "            26,8,16,7, 27,20,13,2, 41,52,31,37, 47,55,30,40,51,45,33,48, 44,49,39,56,34,53,46,42, 50,36,29,32]\n",
    "    bit56 = ''\n",
    "    for i in PC_1:\n",
    "        bit56 +=bit64[i]\n",
    "    L,R = bit56[:28],bit56[28:]\n",
    "    round_keys = []\n",
    "    ones = [1,2,9,16]\n",
    "    for i in range(1,17):\n",
    "        if(i in ones):\n",
    "            l = L[1:]+L[:1]\n",
    "            r = R[1:]+R[:1]\n",
    "        else:\n",
    "            l = L[2:]+L[:2]\n",
    "            r = R[2:]+R[:2]\n",
    "        k = '#'+l+r\n",
    "        sub_key = ''\n",
    "        for i in PC_2:\n",
    "            sub_key += k[i]\n",
    "        L,R = l,r\n",
    "#         print(len(k),len(sub_key))\n",
    "        round_keys.append(sub_key)\n",
    "    return round_keys\n",
    "\n",
    "test = \"133457799BBCDFF1\"\n",
    "subkeys = key_gen(hex2bin(test))\n",
    "[bin2hex(i) for i in subkeys]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "64b7d8da",
   "metadata": {},
   "outputs": [],
   "source": []
  }
 ],
 "metadata": {
  "kernelspec": {
   "display_name": "Python 3 (ipykernel)",
   "language": "python",
   "name": "python3"
  },
  "language_info": {
   "codemirror_mode": {
    "name": "ipython",
    "version": 3
   },
   "file_extension": ".py",
   "mimetype": "text/x-python",
   "name": "python",
   "nbconvert_exporter": "python",
   "pygments_lexer": "ipython3",
   "version": "3.12.3"
  }
 },
 "nbformat": 4,
 "nbformat_minor": 5
}