prysm-pulse/beacon-chain/p2p/fork.go
Raul Jordan f3d6dbcc1e
Move Shared/Params Into Config/Params (#9642)
* config params into pkg

* gaz

Co-authored-by: prylabs-bulldozer[bot] <58059840+prylabs-bulldozer[bot]@users.noreply.github.com>
2021-09-21 19:59:25 +00:00

129 lines
4.1 KiB
Go

package p2p
import (
"bytes"
"fmt"
"time"
"github.com/ethereum/go-ethereum/p2p/enode"
"github.com/ethereum/go-ethereum/p2p/enr"
"github.com/pkg/errors"
"github.com/prysmaticlabs/prysm/beacon-chain/core"
"github.com/prysmaticlabs/prysm/config/params"
"github.com/prysmaticlabs/prysm/network/forks"
pb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
prysmTime "github.com/prysmaticlabs/prysm/time"
"github.com/sirupsen/logrus"
)
// ENR key used for Ethereum consensus-related fork data.
var eth2ENRKey = params.BeaconNetworkConfig().ETH2Key
// ForkDigest returns the current fork digest of
// the node according to the local clock.
func (s *Service) currentForkDigest() ([4]byte, error) {
if !s.isInitialized() {
return [4]byte{}, errors.New("state is not initialized")
}
return forks.CreateForkDigest(s.genesisTime, s.genesisValidatorsRoot)
}
// Compares fork ENRs between an incoming peer's record and our node's
// local record values for current and next fork version/epoch.
func (s *Service) compareForkENR(record *enr.Record) error {
currentRecord := s.dv5Listener.LocalNode().Node().Record()
peerForkENR, err := forkEntry(record)
if err != nil {
return err
}
currentForkENR, err := forkEntry(currentRecord)
if err != nil {
return err
}
enrString, err := SerializeENR(record)
if err != nil {
return err
}
// Clients SHOULD connect to peers with current_fork_digest, next_fork_version,
// and next_fork_epoch that match local values.
if !bytes.Equal(peerForkENR.CurrentForkDigest, currentForkENR.CurrentForkDigest) {
return fmt.Errorf(
"fork digest of peer with ENR %s: %v, does not match local value: %v",
enrString,
peerForkENR.CurrentForkDigest,
currentForkENR.CurrentForkDigest,
)
}
// Clients MAY connect to peers with the same current_fork_version but a
// different next_fork_version/next_fork_epoch. Unless ENRForkID is manually
// updated to matching prior to the earlier next_fork_epoch of the two clients,
// these type of connecting clients will be unable to successfully interact
// starting at the earlier next_fork_epoch.
if peerForkENR.NextForkEpoch != currentForkENR.NextForkEpoch {
log.WithFields(logrus.Fields{
"peerNextForkEpoch": peerForkENR.NextForkEpoch,
"peerENR": enrString,
}).Trace("Peer matches fork digest but has different next fork epoch")
}
if !bytes.Equal(peerForkENR.NextForkVersion, currentForkENR.NextForkVersion) {
log.WithFields(logrus.Fields{
"peerNextForkVersion": peerForkENR.NextForkVersion,
"peerENR": enrString,
}).Trace("Peer matches fork digest but has different next fork version")
}
return nil
}
// Adds a fork entry as an ENR record under the Ethereum consensus EnrKey for
// the local node. The fork entry is an ssz-encoded enrForkID type
// which takes into account the current fork version from the current
// epoch to create a fork digest, the next fork version,
// and the next fork epoch.
func addForkEntry(
node *enode.LocalNode,
genesisTime time.Time,
genesisValidatorsRoot []byte,
) (*enode.LocalNode, error) {
digest, err := forks.CreateForkDigest(genesisTime, genesisValidatorsRoot)
if err != nil {
return nil, err
}
currentSlot := core.SlotsSince(genesisTime)
currentEpoch := core.SlotToEpoch(currentSlot)
if prysmTime.Now().Before(genesisTime) {
currentEpoch = 0
}
nextForkVersion, nextForkEpoch, err := forks.NextForkData(currentEpoch)
if err != nil {
return nil, err
}
enrForkID := &pb.ENRForkID{
CurrentForkDigest: digest[:],
NextForkVersion: nextForkVersion[:],
NextForkEpoch: nextForkEpoch,
}
enc, err := enrForkID.MarshalSSZ()
if err != nil {
return nil, err
}
forkEntry := enr.WithEntry(eth2ENRKey, enc)
node.Set(forkEntry)
return node, nil
}
// Retrieves an enrForkID from an ENR record by key lookup
// under the Ethereum consensus EnrKey
func forkEntry(record *enr.Record) (*pb.ENRForkID, error) {
sszEncodedForkEntry := make([]byte, 16)
entry := enr.WithEntry(eth2ENRKey, &sszEncodedForkEntry)
err := record.Load(entry)
if err != nil {
return nil, err
}
forkEntry := &pb.ENRForkID{}
if err := forkEntry.UnmarshalSSZ(sszEncodedForkEntry); err != nil {
return nil, err
}
return forkEntry, nil
}