go-ethereum/p2p/discover/node.go

134 lines
3.6 KiB
Go

// Copyright 2015 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 discover
import (
"crypto/ecdsa"
"crypto/elliptic"
"errors"
"math/big"
"slices"
"sort"
"time"
"github.com/ethereum/go-ethereum/common/math"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/p2p/enode"
)
type BucketNode struct {
Node *enode.Node `json:"node"`
AddedToTable time.Time `json:"addedToTable"`
AddedToBucket time.Time `json:"addedToBucket"`
Checks int `json:"checks"`
Live bool `json:"live"`
}
// tableNode is an entry in Table.
type tableNode struct {
*enode.Node
revalList *revalidationList
addedToTable time.Time // first time node was added to bucket or replacement list
addedToBucket time.Time // time it was added in the actual bucket
livenessChecks uint // how often liveness was checked
isValidatedLive bool // true if existence of node is considered validated right now
}
type encPubkey [64]byte
func encodePubkey(key *ecdsa.PublicKey) encPubkey {
var e encPubkey
math.ReadBits(key.X, e[:len(e)/2])
math.ReadBits(key.Y, e[len(e)/2:])
return e
}
func decodePubkey(curve elliptic.Curve, e []byte) (*ecdsa.PublicKey, error) {
if len(e) != len(encPubkey{}) {
return nil, errors.New("wrong size public key data")
}
p := &ecdsa.PublicKey{Curve: curve, X: new(big.Int), Y: new(big.Int)}
half := len(e) / 2
p.X.SetBytes(e[:half])
p.Y.SetBytes(e[half:])
if !p.Curve.IsOnCurve(p.X, p.Y) {
return nil, errors.New("invalid curve point")
}
return p, nil
}
func (e encPubkey) id() enode.ID {
return enode.ID(crypto.Keccak256Hash(e[:]))
}
func unwrapNodes(ns []*tableNode) []*enode.Node {
result := make([]*enode.Node, len(ns))
for i, n := range ns {
result[i] = n.Node
}
return result
}
func (n *tableNode) String() string {
return n.Node.String()
}
// nodesByDistance is a list of nodes, ordered by distance to target.
type nodesByDistance struct {
entries []*enode.Node
target enode.ID
}
// push adds the given node to the list, keeping the total size below maxElems.
func (h *nodesByDistance) push(n *enode.Node, maxElems int) {
ix := sort.Search(len(h.entries), func(i int) bool {
return enode.DistCmp(h.target, h.entries[i].ID(), n.ID()) > 0
})
end := len(h.entries)
if len(h.entries) < maxElems {
h.entries = append(h.entries, n)
}
if ix < end {
// Slide existing entries down to make room.
// This will overwrite the entry we just appended.
copy(h.entries[ix+1:], h.entries[ix:])
h.entries[ix] = n
}
}
type nodeType interface {
ID() enode.ID
}
// containsID reports whether ns contains a node with the given ID.
func containsID[N nodeType](ns []N, id enode.ID) bool {
for _, n := range ns {
if n.ID() == id {
return true
}
}
return false
}
// deleteNode removes a node from the list.
func deleteNode[N nodeType](list []N, id enode.ID) []N {
return slices.DeleteFunc(list, func(n N) bool {
return n.ID() == id
})
}