DecryptAuth decrypts a given base64 encoded ciphertext byte array and IV byte array and returns the plaintext as byte array.

EncryptAuth encrypts a plaintext byte array with authentication data byte array and returns the IV and CipherText as byte array.

RandDuration returns a random time.Duration in u with a maximum value of the given n.

RandNum returns a random number with a maximum value of n.

RandomBytes uses the crypto/rand generator to generate random bytes.

RandomStringSecure returns a random, n long string of characters.