Invalid_argument if argument is not keybytes bytes long
Invalid_argument if argument is not keybytes bytes long
val genkey : unit -> keygenkey () generates a secretbox key.
secretbox key nonce msg cmsg encrypts and authenticates the data in msg using key and nonce and outputs the authentication tag and the ciphertext in one buffer cmsg. For this reason, csmg needs to be tagbytes longer than msg.
secretbox_open key nonce cmsg msg verifies and decrypts cmsg using key and nonce and outputs the plaintext in msg. As above, msg is expected to be tagbytes shorter than cmsg. Returns true if operation has succeeded, false otherwise.