Write a program that can encrypt and decrypt files using DES. -- 2

There are 2 parts in this project. The first part is key generation. - The input key will be provided as a hexadecimal string which is equal to 64 bits. - Create the DES key structures. Ex: S-boxes. The second part is encryption and decryption using the first part for key generation. - The key will be provided to the program as a hexadecimal string. The plain text must be in binary form and should be multiples of 64. - Use the work from Part-1 to encrypt a file. - The cipher should operate in chained black cipher (CBC) mode. The initialization vector will be 0. - The input can be any length. You must be able to encrypt and decrypt multiple blocks. CBC requires complete blocks, so the program should pad incomplete final blocks. You may assume that input to encryption will be text-only and pad partial blocks with zeroes. This allows you to discard bytes with the values 0 while decrypting. - The program should run from a terminal and given options instructing the program to encrypt and decrypt and specifying the key, input file, and output file (Ex: "program -e 0x9ad5b4ef infile outfile"). Do not prompt for additional input.