bsc/les/enr_entry.go
Felföldi Zsolt a72fa88a0d
les: switch to new discv5 (#21940)
This PR enables running the new discv5 protocol in both LES client
and server mode. In client mode it mixes discv5 and dnsdisc iterators
(if both are enabled) and filters incoming ENRs for "les" tag and fork ID.
The old p2p/discv5 package and all references to it are removed.

Co-authored-by: Felix Lange <fjl@twurst.com>
2021-01-26 21:41:35 +01:00

73 lines
2.4 KiB
Go

// Copyright 2019 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package les
import (
"github.com/ethereum/go-ethereum/core/forkid"
"github.com/ethereum/go-ethereum/p2p"
"github.com/ethereum/go-ethereum/p2p/dnsdisc"
"github.com/ethereum/go-ethereum/p2p/enode"
"github.com/ethereum/go-ethereum/rlp"
)
// lesEntry is the "les" ENR entry. This is set for LES servers only.
type lesEntry struct {
// Ignore additional fields (for forward compatibility).
_ []rlp.RawValue `rlp:"tail"`
}
func (lesEntry) ENRKey() string { return "les" }
// ethEntry is the "eth" ENR entry. This is redeclared here to avoid depending on package eth.
type ethEntry struct {
ForkID forkid.ID
_ []rlp.RawValue `rlp:"tail"`
}
func (ethEntry) ENRKey() string { return "eth" }
// setupDiscovery creates the node discovery source for the eth protocol.
func (eth *LightEthereum) setupDiscovery(cfg *p2p.Config) (enode.Iterator, error) {
it := enode.NewFairMix(0)
// Enable DNS discovery.
if len(eth.config.EthDiscoveryURLs) != 0 {
client := dnsdisc.NewClient(dnsdisc.Config{})
dns, err := client.NewIterator(eth.config.EthDiscoveryURLs...)
if err != nil {
return nil, err
}
it.AddSource(dns)
}
// Enable DHT.
if cfg.DiscoveryV5 && eth.p2pServer.DiscV5 != nil {
it.AddSource(eth.p2pServer.DiscV5.RandomNodes())
}
forkFilter := forkid.NewFilter(eth.blockchain)
iterator := enode.Filter(it, func(n *enode.Node) bool { return nodeIsServer(forkFilter, n) })
return iterator, nil
}
// nodeIsServer checks whether n is an LES server node.
func nodeIsServer(forkFilter forkid.Filter, n *enode.Node) bool {
var les lesEntry
var eth ethEntry
return n.Load(&les) == nil && n.Load(&eth) == nil && forkFilter(eth.ForkID) == nil
}