/CS457_2021

Primary LanguageC

# Assignment 1

Run the programm as follows:

	crypto MODE TESTFILE

where MODE is:

	1. 'O' --> One Time Pad(OTP)
	2. 'C' --> Caesar's Cipher
	3. 'A' --> Affine Cipher
	4. 'P' --> Playfair Cipher
	5. 'F' --> Feistel Cipher

and TESTFILE is the name of the testfile for encrpyption/decryption.

Extra Functions:

	1. generateKey(long int size) / Generates a random key of size = size
	 using /dev/urandom for use in OTP encryption/decryption.
	
	2. removeIllegal(uint8_t *plaintext) / Removes illegal chars 
	(anything other than a-zA-z0-9) from plaintext. 

	3. removeAffineIllegal(uint8_t* plaintext); / Removes illegal chars 
	(anything other than a-zA-z) from plaintext. 

	4. removeDup(char* key); / Removes duplicate letters from key.