exit

type Exit struct {

	// ID is the identifier that will be embedded with the response to this message
	// relayed from the exit service.
	ID nonce.ID

	// Ciphers is a set of 3 symmetric ciphers that are to be used in their
	// given order over the reply message from the service.
	crypto.Ciphers

	// Nonces are the nonces to use with the cipher when creating the
	// encryption for the reply message,
	// they are common with the crypts in the header.
	crypto.Nonces

	// Port identifies the type of service as well as being the port used by the
	// service to be relayed to. This should be the well-known protocol associated
	// with the port number, eg 80 for HTTP, 53 for DNS, etc.
	Port uint16

	// Bytes are the message to be passed to the exit service.
	slice.Bytes

	// Onion contains the rest of the message, in this case the reply RoutingHeader.
	ont.Onion
}

type ExitPoint struct {

	// Routing contains all the information required to generate a RoutingHeader and
	// cipher/nonce set.
	*Routing

	// ReturnPubs are the public keys of the session payload, which are not in the
	// message but previously shared to create a session.
	ReturnPubs crypto.Pubs
}

type Params struct {
	Port       uint16
	Payload    slice.Bytes
	ID         nonce.ID
	Alice, Bob *sessions.Data
	S          sessions.Circuit
	KS         *crypto.KeySet
}

type Routing struct {

	// Sessions that the RoutingHeader is using.
	Sessions [3]*sessions.Data

	// Keys being used to form the other ECDH half for the encryption.
	Keys crypto.Privs

	// The three nonces that match up with each of the three session RoutingHeader
	// Crypt nonces.
	crypto.Nonces
}