dm

type DMCipher interface {
	// CiphertextOverhead returns the ciphertext overhead in bytes.
	CiphertextOverhead() int

	// Encrypt encrypts the given plaintext as an encrypted Direct message.
	Encrypt(plaintext []byte,
		senderStaticPrivKey nike.PrivateKey,
		partnerStaticPubKey nike.PublicKey,
		rng io.Reader,
		maxPayloadSize int) (ciphertext []byte)

	// Decrypt decrypts the given ciphertext encrypted as a Direct
	// message.
	Decrypt(ciphertext []byte, senderStaticPrivKey nike.PrivateKey) (
		partnerStaticPublicKey nike.PublicKey, plaintext []byte,
		err error)

	// IsSelfEncrypted will return whether the ciphertext provided has been
	// encrypted by the owner of the passed in private key. Returns true
	// if the ciphertext has been encrypted by the user.
	IsSelfEncrypted(data []byte, myPrivateKey nike.PrivateKey) bool

	// EncryptSelf will encrypt the passed plaintext. This will simulate the
	// encryption protocol in Encrypt, using just the user's public key.
	EncryptSelf(plaintext []byte, myPrivateKey nike.PrivateKey,
		partnerStaticPubKey nike.PublicKey,
		maxPayloadSize int) ([]byte, error)

	// DecryptSelf will decrypt the passed ciphertext. This will
	// check if the ciphertext is expected using IsSelfEncrypted.
	DecryptSelf(ciphertext []byte, myPrivateKey nike.PrivateKey) (
		partnerstaticPubKey nike.PublicKey, plaintext []byte, err error)
}

type NoiseCipher interface {
	// CiphertextOverhead returns the ciphertext overhead in bytes.
	CiphertextOverhead() int

	// Encrypt encrypts the given plaintext as a Noise X message.
	// - plaintext: The message to Encrypt
	// - partnerStaticPubKey: The public key of the target of the message
	// - rng: a cryptographically secure pseudo random number generator
	Encrypt(plaintext []byte,
		partnerStaticPubKey nike.PublicKey,
		rng io.Reader) []byte

	// Decrypt decrypts the given ciphertext as a Noise X message.
	Decrypt(ciphertext []byte,
		myStatic nike.PrivateKey) ([]byte, error)
}