peer_name_mac.go

// The !peer_name_alternative effectively makes this the default,
// i.e. to choose an alternative, run "go build -tags
// 'peer_name_alternative peer_name_hash'"

// +build peer_name_mac !peer_name_alternative

// Let peer names be MACs...
//
// MACs need to be unique across our network, or bad things will
// happen anyway. So they make pretty good candidates for peer
// names. And doing so is pretty efficient both computationally and
// network overhead wise.
//
// Note that we do not mandate *what* MAC should be used as the peer
// name. In particular it doesn't actually have to be the MAC of, say,
// the network interface the peer is sniffing on.
package weave

import (
	"net"
)

// PeerName is used as a map key. Since net.HardwareAddr isn't
// suitable for that - it's a slice, and slices can't be map keys - we
// convert that to/from uint64.
type PeerName uint64

const (
	PeerNameFlavour = "mac"
	NameSize        = 6
	UnknownPeerName = PeerName(0)
)

func PeerNameFromUserInput(userInput string) (PeerName, error) {
	res, err := PeerNameFromString(userInput)
	return res, err
}

func PeerNameFromString(nameStr string) (PeerName, error) {
	mac, err := net.ParseMAC(nameStr)
	if err != nil {
		return UnknownPeerName, err
	}
	return PeerName(macint(mac)), nil
}

func PeerNameFromBin(nameByte []byte) PeerName {
	return PeerName(macint(net.HardwareAddr(nameByte)))
}

func (name PeerName) Bin() []byte {
	return intmac(uint64(name))
}

func (name PeerName) String() string {
	return intmac(uint64(name)).String()
}