go-ethereum/cmd/devp2p/rlpxcmd.go

95 lines
2.4 KiB
Go

// Copyright 2020 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 main
import (
"fmt"
"net"
"github.com/ethereum/go-ethereum/common/hexutil"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/p2p"
"github.com/ethereum/go-ethereum/p2p/rlpx"
"github.com/ethereum/go-ethereum/rlp"
"gopkg.in/urfave/cli.v1"
)
var (
rlpxCommand = cli.Command{
Name: "rlpx",
Usage: "RLPx Commands",
Subcommands: []cli.Command{
rlpxPingCommand,
},
}
rlpxPingCommand = cli.Command{
Name: "ping",
Usage: "Perform a RLPx handshake",
ArgsUsage: "<node>",
Action: rlpxPing,
}
)
func rlpxPing(ctx *cli.Context) error {
n := getNodeArg(ctx)
fd, err := net.Dial("tcp", fmt.Sprintf("%v:%d", n.IP(), n.TCP()))
if err != nil {
return err
}
conn := rlpx.NewConn(fd, n.Pubkey())
ourKey, _ := crypto.GenerateKey()
_, err = conn.Handshake(ourKey)
if err != nil {
return err
}
code, data, _, err := conn.Read()
if err != nil {
return err
}
switch code {
case 0:
var h devp2pHandshake
if err := rlp.DecodeBytes(data, &h); err != nil {
return fmt.Errorf("invalid handshake: %v", err)
}
fmt.Printf("%+v\n", h)
case 1:
var msg []p2p.DiscReason
if rlp.DecodeBytes(data, &msg); len(msg) == 0 {
return fmt.Errorf("invalid disconnect message")
}
return fmt.Errorf("received disconnect message: %v", msg[0])
default:
return fmt.Errorf("invalid message code %d, expected handshake (code zero)", code)
}
return nil
}
// devp2pHandshake is the RLP structure of the devp2p protocol handshake.
type devp2pHandshake struct {
Version uint64
Name string
Caps []p2p.Cap
ListenPort uint64
ID hexutil.Bytes // secp256k1 public key
// Ignore additional fields (for forward compatibility).
Rest []rlp.RawValue `rlp:"tail"`
}