Homework 2 - Permutation Cipher in C++ The permutation ciphers are used to generate a ciphertext (encrypted text) by re-arranging the position of the letters in a given plaintext

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Homework 2 - Permutation Cipher in C++ The permutation ciphers are used to generate a ciphertext (encrypted text) by re-arranging the position of the letters in a given plaintext. How does it work? 1. Select the block size (n) and a permutation. 2. Divide a given plaintext into blocks of n letters and use ‘x’ as padding, if necessary. 3. Apply a permutation to each block and generate the encrypted ciphertext. For example, for n = 4 and permutation of (2, 1, 4, 3) Unencrypted plaintext is gentlemen do not read each other’s mail [1] 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 gent leme n do not rea d ea ch o ther ’s m ailx 2143 2143 2143 2143 2143 2143 2143 2143 2143 2143 egtn elem nod n to r ae dae hco htre s’m iaxl Encrypted ciphertext is egtnelem nodn tor ae daehco htres’m iaxl The program needs to get the following information from the user: • To encrypt: a text file that includes the plaintext, and a block size and the permutation information via standard input (keyboard). • To decrypt: a binary file that includes an encrypted ciphertext, and a block size and the permutation information via standard input (keyboard). Here's what a sample run should look like: > ./PermCipher Usage: ./PermCipher option -i InputFileName -o OutputFileName Options: -e Encrypt -d Decrypt > ./PermCipher -e -i PlaintextFile -o CiphertextFile Welcome to the Permutation Cipher Selected Mode: Encrypt Input File: PlaintextFile Output File: CiphertextFile Please enter the block size (2-8) and the permutation (e.g., 4 2413): 4 2143 Encrypted ciphertext file: egtnelem nodn tor ae daehco htres’m iaxl > ./PermCipher -d -i CiphertextFile -o PlaintextFile Welcome to the Permutation Cipher Selected Mode: Decrypt Input File: CiphertextFile Output File: PlaintextFile Please enter the block size (2-8) and the permutation (e.g., 4 2413): 4 2143 Decrypted ciphertext file: gentlemen do not read each other’s mail The program should be able to process up to 8 characters at each block with a minimum of 2 characters. Submit your makefile, source code (encrypt.h encrypt.cpp, decrypt.h, decrypt.cpp, main.cpp) and test files to your BitBucket repository csci221-HW02. [1]