go-ethereum/p2p/discover/node.go
Felix Lange 94a8b296e4
p2p/discover: refactor node and endpoint representation (#29844)
Here we clean up internal uses of type discover.node, converting most code to use
enode.Node instead. The discover.node type used to be the canonical representation of
network hosts before ENR was introduced. Most code worked with *node to avoid conversions
when interacting with Table methods. Since *node also contains internal state of Table and
is a mutable type, using *node outside of Table code is prone to data races. It's also
cleaner not having to wrap/unwrap *enode.Node all the time.

discover.node has been renamed to tableNode to clarify its purpose.

While here, we also change most uses of net.UDPAddr into netip.AddrPort. While this is
technically a separate refactoring from the *node -> *enode.Node change, it is more
convenient because *enode.Node handles IP addresses as netip.Addr. The switch to package
netip in discovery would've happened very soon anyway.

The change to netip.AddrPort stops at certain interface points. For example, since package
p2p/netutil has not been converted to use netip.Addr yet, we still have to convert to
net.IP/net.UDPAddr in a few places.
2024-05-29 15:02:26 +02:00

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
})
}