api

type Factory interface {
	// Name returns the name of the implementation.
	Name() string

	// New constructs a new keyed instance.
	New(key []byte) Instance
}

type Instance interface {
	// E authenticate and encrypts ad/msg with the nonce, and writes
	// ciphertext || tag to dst.
	E(nonce, dst, ad, msg []byte)

	// D decrypts and authenticates ad/ct with the nonce and writes
	// the plaintext to dst, and returns true iff the authentication
	// succeeds.
	//
	// Callers MUST scrub dst iff the call returns false.
	//
	// Note: dst is guaranteed NOT to alias with ct.
	D(nonce, dst, ad, ct []byte) bool
}