go-ethereum/cmd/devp2p/internal/ethtest/conn.go
2024-02-08 15:49:19 +02:00

362 lines
11 KiB
Go

// Copyright 2023 The go-ethereum Authors
// This file is part of go-ethereum.
//
// go-ethereum is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// go-ethereum 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.
package ethtest
import (
"crypto/ecdsa"
"errors"
"fmt"
"net"
"reflect"
"time"
"github.com/davecgh/go-spew/spew"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/eth/protocols/eth"
"github.com/ethereum/go-ethereum/eth/protocols/snap"
"github.com/ethereum/go-ethereum/p2p"
"github.com/ethereum/go-ethereum/p2p/rlpx"
"github.com/ethereum/go-ethereum/rlp"
)
var (
pretty = spew.ConfigState{
Indent: " ",
DisableCapacities: true,
DisablePointerAddresses: true,
SortKeys: true,
}
timeout = 2 * time.Second
)
// dial attempts to dial the given node and perform a handshake, returning the
// created Conn if successful.
func (s *Suite) dial() (*Conn, error) {
key, _ := crypto.GenerateKey()
return s.dialAs(key)
}
// dialAs attempts to dial a given node and perform a handshake using the given
// private key.
func (s *Suite) dialAs(key *ecdsa.PrivateKey) (*Conn, error) {
fd, err := net.Dial("tcp", fmt.Sprintf("%v:%d", s.Dest.IP(), s.Dest.TCP()))
if err != nil {
return nil, err
}
conn := Conn{Conn: rlpx.NewConn(fd, s.Dest.Pubkey())}
conn.ourKey = key
_, err = conn.Handshake(conn.ourKey)
if err != nil {
conn.Close()
return nil, err
}
conn.caps = []p2p.Cap{
{Name: "eth", Version: 67},
{Name: "eth", Version: 68},
}
conn.ourHighestProtoVersion = 68
return &conn, nil
}
// dialSnap creates a connection with snap/1 capability.
func (s *Suite) dialSnap() (*Conn, error) {
conn, err := s.dial()
if err != nil {
return nil, fmt.Errorf("dial failed: %v", err)
}
conn.caps = append(conn.caps, p2p.Cap{Name: "snap", Version: 1})
conn.ourHighestSnapProtoVersion = 1
return conn, nil
}
// Conn represents an individual connection with a peer
type Conn struct {
*rlpx.Conn
ourKey *ecdsa.PrivateKey
negotiatedProtoVersion uint
negotiatedSnapProtoVersion uint
ourHighestProtoVersion uint
ourHighestSnapProtoVersion uint
caps []p2p.Cap
}
// Read reads a packet from the connection.
func (c *Conn) Read() (uint64, []byte, error) {
c.SetReadDeadline(time.Now().Add(timeout))
code, data, _, err := c.Conn.Read()
if err != nil {
return 0, nil, err
}
return code, data, nil
}
// ReadMsg attempts to read a devp2p message with a specific code.
func (c *Conn) ReadMsg(proto Proto, code uint64, msg any) error {
c.SetReadDeadline(time.Now().Add(timeout))
for {
got, data, err := c.Read()
if err != nil {
return err
}
if protoOffset(proto)+code == got {
return rlp.DecodeBytes(data, msg)
}
}
}
// Write writes a eth packet to the connection.
func (c *Conn) Write(proto Proto, code uint64, msg any) error {
c.SetWriteDeadline(time.Now().Add(timeout))
payload, err := rlp.EncodeToBytes(msg)
if err != nil {
return err
}
_, err = c.Conn.Write(protoOffset(proto)+code, payload)
return err
}
// ReadEth reads an Eth sub-protocol wire message.
func (c *Conn) ReadEth() (any, error) {
c.SetReadDeadline(time.Now().Add(timeout))
for {
code, data, _, err := c.Conn.Read()
if err != nil {
return nil, err
}
if code == pingMsg {
c.Write(baseProto, pongMsg, []byte{})
continue
}
if getProto(code) != ethProto {
// Read until eth message.
continue
}
code -= baseProtoLen
var msg any
switch int(code) {
case eth.StatusMsg:
msg = new(eth.StatusPacket)
case eth.GetBlockHeadersMsg:
msg = new(eth.GetBlockHeadersPacket)
case eth.BlockHeadersMsg:
msg = new(eth.BlockHeadersPacket)
case eth.GetBlockBodiesMsg:
msg = new(eth.GetBlockBodiesPacket)
case eth.BlockBodiesMsg:
msg = new(eth.BlockBodiesPacket)
case eth.NewBlockMsg:
msg = new(eth.NewBlockPacket)
case eth.NewBlockHashesMsg:
msg = new(eth.NewBlockHashesPacket)
case eth.TransactionsMsg:
msg = new(eth.TransactionsPacket)
case eth.NewPooledTransactionHashesMsg:
msg = new(eth.NewPooledTransactionHashesPacket)
case eth.GetPooledTransactionsMsg:
msg = new(eth.GetPooledTransactionsPacket)
case eth.PooledTransactionsMsg:
msg = new(eth.PooledTransactionsPacket)
default:
panic(fmt.Sprintf("unhandled eth msg code %d", code))
}
if err := rlp.DecodeBytes(data, msg); err != nil {
return nil, fmt.Errorf("unable to decode eth msg: %v", err)
}
return msg, nil
}
}
// ReadSnap reads a snap/1 response with the given id from the connection.
func (c *Conn) ReadSnap() (any, error) {
c.SetReadDeadline(time.Now().Add(timeout))
for {
code, data, _, err := c.Conn.Read()
if err != nil {
return nil, err
}
if getProto(code) != snapProto {
// Read until snap message.
continue
}
code -= baseProtoLen + ethProtoLen
var msg any
switch int(code) {
case snap.GetAccountRangeMsg:
msg = new(snap.GetAccountRangePacket)
case snap.AccountRangeMsg:
msg = new(snap.AccountRangePacket)
case snap.GetStorageRangesMsg:
msg = new(snap.GetStorageRangesPacket)
case snap.StorageRangesMsg:
msg = new(snap.StorageRangesPacket)
case snap.GetByteCodesMsg:
msg = new(snap.GetByteCodesPacket)
case snap.ByteCodesMsg:
msg = new(snap.ByteCodesPacket)
case snap.GetTrieNodesMsg:
msg = new(snap.GetTrieNodesPacket)
case snap.TrieNodesMsg:
msg = new(snap.TrieNodesPacket)
default:
panic(fmt.Errorf("unhandled snap code: %d", code))
}
if err := rlp.DecodeBytes(data, msg); err != nil {
return nil, fmt.Errorf("could not rlp decode message: %v", err)
}
return msg, nil
}
}
// peer performs both the protocol handshake and the status message
// exchange with the node in order to peer with it.
func (c *Conn) peer(chain *Chain, status *eth.StatusPacket) error {
if err := c.handshake(); err != nil {
return fmt.Errorf("handshake failed: %v", err)
}
if err := c.statusExchange(chain, status); err != nil {
return fmt.Errorf("status exchange failed: %v", err)
}
return nil
}
// handshake performs a protocol handshake with the node.
func (c *Conn) handshake() error {
// Write hello to client.
pub0 := crypto.FromECDSAPub(&c.ourKey.PublicKey)[1:]
ourHandshake := &protoHandshake{
Version: 5,
Caps: c.caps,
ID: pub0,
}
if err := c.Write(baseProto, handshakeMsg, ourHandshake); err != nil {
return fmt.Errorf("write to connection failed: %v", err)
}
// Read hello from client.
code, data, err := c.Read()
if err != nil {
return fmt.Errorf("erroring reading handshake: %v", err)
}
switch code {
case handshakeMsg:
msg := new(protoHandshake)
if err := rlp.DecodeBytes(data, &msg); err != nil {
return fmt.Errorf("error decoding handshake msg: %v", err)
}
// Set snappy if version is at least 5.
if msg.Version >= 5 {
c.SetSnappy(true)
}
c.negotiateEthProtocol(msg.Caps)
if c.negotiatedProtoVersion == 0 {
return fmt.Errorf("could not negotiate eth protocol (remote caps: %v, local eth version: %v)", msg.Caps, c.ourHighestProtoVersion)
}
// If we require snap, verify that it was negotiated.
if c.ourHighestSnapProtoVersion != c.negotiatedSnapProtoVersion {
return fmt.Errorf("could not negotiate snap protocol (remote caps: %v, local snap version: %v)", msg.Caps, c.ourHighestSnapProtoVersion)
}
return nil
default:
return fmt.Errorf("bad handshake: got msg code %d", code)
}
}
// negotiateEthProtocol sets the Conn's eth protocol version to highest
// advertised capability from peer.
func (c *Conn) negotiateEthProtocol(caps []p2p.Cap) {
var highestEthVersion uint
var highestSnapVersion uint
for _, capability := range caps {
switch capability.Name {
case "eth":
if capability.Version > highestEthVersion && capability.Version <= c.ourHighestProtoVersion {
highestEthVersion = capability.Version
}
case "snap":
if capability.Version > highestSnapVersion && capability.Version <= c.ourHighestSnapProtoVersion {
highestSnapVersion = capability.Version
}
}
}
c.negotiatedProtoVersion = highestEthVersion
c.negotiatedSnapProtoVersion = highestSnapVersion
}
// statusExchange performs a `Status` message exchange with the given node.
func (c *Conn) statusExchange(chain *Chain, status *eth.StatusPacket) error {
loop:
for {
code, data, err := c.Read()
if err != nil {
return fmt.Errorf("failed to read from connection: %w", err)
}
switch code {
case eth.StatusMsg + protoOffset(ethProto):
msg := new(eth.StatusPacket)
if err := rlp.DecodeBytes(data, &msg); err != nil {
return fmt.Errorf("error decoding status packet: %w", err)
}
if have, want := msg.Head, chain.blocks[chain.Len()-1].Hash(); have != want {
return fmt.Errorf("wrong head block in status, want: %#x (block %d) have %#x",
want, chain.blocks[chain.Len()-1].NumberU64(), have)
}
if have, want := msg.TD.Cmp(chain.TD()), 0; have != want {
return fmt.Errorf("wrong TD in status: have %v want %v", have, want)
}
if have, want := msg.ForkID, chain.ForkID(); !reflect.DeepEqual(have, want) {
return fmt.Errorf("wrong fork ID in status: have %v, want %v", have, want)
}
if have, want := msg.ProtocolVersion, c.ourHighestProtoVersion; have != uint32(want) {
return fmt.Errorf("wrong protocol version: have %v, want %v", have, want)
}
break loop
case discMsg:
var msg []p2p.DiscReason
if rlp.DecodeBytes(data, &msg); len(msg) == 0 {
return errors.New("invalid disconnect message")
}
return fmt.Errorf("disconnect received: %v", pretty.Sdump(msg))
case pingMsg:
// TODO (renaynay): in the future, this should be an error
// (PINGs should not be a response upon fresh connection)
c.Write(baseProto, pongMsg, nil)
default:
return fmt.Errorf("bad status message: code %d", code)
}
}
// make sure eth protocol version is set for negotiation
if c.negotiatedProtoVersion == 0 {
return errors.New("eth protocol version must be set in Conn")
}
if status == nil {
// default status message
status = &eth.StatusPacket{
ProtocolVersion: uint32(c.negotiatedProtoVersion),
NetworkID: chain.config.ChainID.Uint64(),
TD: chain.TD(),
Head: chain.blocks[chain.Len()-1].Hash(),
Genesis: chain.blocks[0].Hash(),
ForkID: chain.ForkID(),
}
}
if err := c.Write(ethProto, eth.StatusMsg, status); err != nil {
return fmt.Errorf("write to connection failed: %v", err)
}
return nil
}