go-waku/waku/v2/protocol/enr/localnode.go

131 lines
3.4 KiB
Go

package enr
import (
"crypto/ecdsa"
"encoding/binary"
"errors"
"math"
"math/rand"
"net"
"time"
"github.com/ethereum/go-ethereum/p2p/enode"
"github.com/ethereum/go-ethereum/p2p/enr"
"github.com/multiformats/go-multiaddr"
)
func NewLocalnode(priv *ecdsa.PrivateKey) (*enode.LocalNode, error) {
db, err := enode.OpenDB("")
if err != nil {
return nil, err
}
return enode.NewLocalNode(db, priv), nil
}
type ENROption func(*enode.LocalNode) error
func WithMultiaddress(multiaddrs ...multiaddr.Multiaddr) ENROption {
return func(localnode *enode.LocalNode) (err error) {
// Randomly shuffle multiaddresses
rand.Seed(time.Now().UnixNano())
rand.Shuffle(len(multiaddrs), func(i, j int) { multiaddrs[i], multiaddrs[j] = multiaddrs[j], multiaddrs[i] })
// Adding extra multiaddresses. Should probably not exceed the enr max size of 300bytes
failedOnceWritingENR := false
couldWriteENRatLeastOnce := false
successIdx := -1
for i := len(multiaddrs) - 1; i >= 0; i-- {
err = writeMultiaddressField(localnode, multiaddrs[0:i])
if err == nil {
couldWriteENRatLeastOnce = true
successIdx = i
break
} else {
failedOnceWritingENR = true
}
}
if failedOnceWritingENR && couldWriteENRatLeastOnce {
// Could write a subset of multiaddresses but not all
err = writeMultiaddressField(localnode, multiaddrs[0:successIdx])
if err != nil {
return errors.New("could not write new ENR")
}
}
return nil
}
}
func WithCapabilities(lightpush, filter, store, relay bool) ENROption {
return func(localnode *enode.LocalNode) (err error) {
wakuflags := NewWakuEnrBitfield(lightpush, filter, store, relay)
return WithWakuBitfield(wakuflags)(localnode)
}
}
func WithWakuBitfield(flags WakuEnrBitfield) ENROption {
return func(localnode *enode.LocalNode) (err error) {
localnode.Set(enr.WithEntry(WakuENRField, flags))
return nil
}
}
func WithIP(ipAddr *net.TCPAddr) ENROption {
return func(localnode *enode.LocalNode) (err error) {
localnode.SetStaticIP(ipAddr.IP)
localnode.Set(enr.TCP(uint16(ipAddr.Port))) // TODO: ipv6?
return nil
}
}
func WithUDPPort(udpPort uint) ENROption {
return func(localnode *enode.LocalNode) (err error) {
if udpPort > math.MaxUint16 {
return errors.New("invalid udp port number")
}
localnode.SetFallbackUDP(int(udpPort))
return nil
}
}
func Update(localnode *enode.LocalNode, enrOptions ...ENROption) error {
for _, opt := range enrOptions {
err := opt(localnode)
if err != nil {
return err
}
}
return nil
}
func writeMultiaddressField(localnode *enode.LocalNode, addrAggr []multiaddr.Multiaddr) (err error) {
defer func() {
if e := recover(); e != nil {
// Deleting the multiaddr entry, as we could not write it succesfully
localnode.Delete(enr.WithEntry(MultiaddrENRField, struct{}{}))
err = errors.New("could not write enr record")
}
}()
var fieldRaw []byte
for _, addr := range addrAggr {
maRaw := addr.Bytes()
maSize := make([]byte, 2)
binary.BigEndian.PutUint16(maSize, uint16(len(maRaw)))
fieldRaw = append(fieldRaw, maSize...)
fieldRaw = append(fieldRaw, maRaw...)
}
if len(fieldRaw) != 0 && len(fieldRaw) <= 100 { // Max length for multiaddr field before triggering the 300 bytes limit
localnode.Set(enr.WithEntry(MultiaddrENRField, fieldRaw))
}
// This is to trigger the signing record err due to exceeding 300bytes limit
_ = localnode.Node()
return nil
}