kem

type PrivateKey interface {
	encoding.BinaryMarshaler

	// Returns the scheme for this private key
	Scheme() Scheme

	// Equal returns true if the two keys are equal.
	Equal(PrivateKey) bool

	// Public returns the public key related to this private key.
	Public() PublicKey
}

type PublicKey interface {
	encoding.TextMarshaler
	encoding.BinaryMarshaler

	// Returns the scheme for this public key
	Scheme() Scheme

	Equal(PublicKey) bool
}

type Scheme interface {
	// Name of the scheme
	Name() string

	// GenerateKeyPair creates a new key pair.
	GenerateKeyPair() (PublicKey, PrivateKey, error)

	// Encapsulate generates a shared key ss for the public key and
	// encapsulates it into a ciphertext ct.
	Encapsulate(pk PublicKey) (ct, ss []byte, err error)

	// Returns the shared key encapsulated in ciphertext ct for the
	// private key sk.
	Decapsulate(sk PrivateKey, ct []byte) ([]byte, error)

	// UnmarshalBinaryPublicKey unmarshals a PublicKey from the provided buffer.
	UnmarshalBinaryPublicKey([]byte) (PublicKey, error)

	// UnmarshalBinaryPrivateKey unmarshals a PrivateKey from the provided buffer.
	UnmarshalBinaryPrivateKey([]byte) (PrivateKey, error)

	// UnmarshalTextPublicKey unmarshals a PublicKey from the provided text.
	UnmarshalTextPublicKey([]byte) (PublicKey, error)

	// UnmarshalTextPrivateKey unmarshals a PrivateKey from the provided text.
	UnmarshalTextPrivateKey([]byte) (PrivateKey, error)

	// Size of encapsulated keys.
	CiphertextSize() int

	// Size of established shared keys.
	SharedKeySize() int

	// Size of packed private keys.
	PrivateKeySize() int

	// Size of packed public keys.
	PublicKeySize() int

	// DeriveKeyPair deterministicallly derives a pair of keys from a seed.
	// Panics if the length of seed is not equal to the value returned by
	// SeedSize.
	DeriveKeyPair(seed []byte) (PublicKey, PrivateKey)

	// Size of seed used in DeriveKey
	SeedSize() int
}