go-ethereum/p2p/discover/v5wire/msg.go

250 lines
7.6 KiB
Go

// Copyright 2020 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 v5wire
import (
"fmt"
"net"
"github.com/ethereum/go-ethereum/common/mclock"
"github.com/ethereum/go-ethereum/p2p/enode"
"github.com/ethereum/go-ethereum/p2p/enr"
"github.com/ethereum/go-ethereum/rlp"
)
// Packet is implemented by all message types.
type Packet interface {
Name() string // Name returns a string corresponding to the message type.
Kind() byte // Kind returns the message type.
RequestID() []byte // Returns the request ID.
SetRequestID([]byte) // Sets the request ID.
}
// Message types.
const (
PingMsg byte = iota + 1
PongMsg
FindnodeMsg
NodesMsg
TalkRequestMsg
TalkResponseMsg
RequestTicketMsg
TicketMsg
RegtopicMsg
RegconfirmationMsg
TopicQueryMsg
UnknownPacket = byte(255) // any non-decryptable packet
WhoareyouPacket = byte(254) // the WHOAREYOU packet
)
// Protocol messages.
type (
// Unknown represents any packet that can't be decrypted.
Unknown struct {
Nonce Nonce
}
// WHOAREYOU contains the handshake challenge.
Whoareyou struct {
ChallengeData []byte // Encoded challenge
Nonce Nonce // Nonce of request packet
IDNonce [16]byte // Identity proof data
RecordSeq uint64 // ENR sequence number of recipient
// Node is the locally known node record of recipient.
// This must be set by the caller of Encode.
Node *enode.Node
sent mclock.AbsTime // for handshake GC.
}
// PING is sent during liveness checks.
Ping struct {
ReqID []byte
ENRSeq uint64
}
// PONG is the reply to PING.
Pong struct {
ReqID []byte
ENRSeq uint64
ToIP net.IP // These fields should mirror the UDP envelope address of the ping
ToPort uint16 // packet, which provides a way to discover the external address (after NAT).
}
// FINDNODE is a query for nodes in the given bucket.
Findnode struct {
ReqID []byte
Distances []uint
}
// NODES is the reply to FINDNODE and TOPICQUERY.
Nodes struct {
ReqID []byte
Total uint8
Nodes []*enr.Record
}
// TALKREQ is an application-level request.
TalkRequest struct {
ReqID []byte
Protocol string
Message []byte
}
// TALKRESP is the reply to TALKREQ.
TalkResponse struct {
ReqID []byte
Message []byte
}
// REQUESTTICKET requests a ticket for a topic queue.
RequestTicket struct {
ReqID []byte
Topic []byte
}
// TICKET is the response to REQUESTTICKET.
Ticket struct {
ReqID []byte
Ticket []byte
}
// REGTOPIC registers the sender in a topic queue using a ticket.
Regtopic struct {
ReqID []byte
Ticket []byte
ENR *enr.Record
}
// REGCONFIRMATION is the reply to REGTOPIC.
Regconfirmation struct {
ReqID []byte
Registered bool
}
// TOPICQUERY asks for nodes with the given topic.
TopicQuery struct {
ReqID []byte
Topic []byte
}
)
// DecodeMessage decodes the message body of a packet.
func DecodeMessage(ptype byte, body []byte) (Packet, error) {
var dec Packet
switch ptype {
case PingMsg:
dec = new(Ping)
case PongMsg:
dec = new(Pong)
case FindnodeMsg:
dec = new(Findnode)
case NodesMsg:
dec = new(Nodes)
case TalkRequestMsg:
dec = new(TalkRequest)
case TalkResponseMsg:
dec = new(TalkResponse)
case RequestTicketMsg:
dec = new(RequestTicket)
case TicketMsg:
dec = new(Ticket)
case RegtopicMsg:
dec = new(Regtopic)
case RegconfirmationMsg:
dec = new(Regconfirmation)
case TopicQueryMsg:
dec = new(TopicQuery)
default:
return nil, fmt.Errorf("unknown packet type %d", ptype)
}
if err := rlp.DecodeBytes(body, dec); err != nil {
return nil, err
}
if dec.RequestID() != nil && len(dec.RequestID()) > 8 {
return nil, ErrInvalidReqID
}
return dec, nil
}
func (*Whoareyou) Name() string { return "WHOAREYOU/v5" }
func (*Whoareyou) Kind() byte { return WhoareyouPacket }
func (*Whoareyou) RequestID() []byte { return nil }
func (*Whoareyou) SetRequestID([]byte) {}
func (*Unknown) Name() string { return "UNKNOWN/v5" }
func (*Unknown) Kind() byte { return UnknownPacket }
func (*Unknown) RequestID() []byte { return nil }
func (*Unknown) SetRequestID([]byte) {}
func (*Ping) Name() string { return "PING/v5" }
func (*Ping) Kind() byte { return PingMsg }
func (p *Ping) RequestID() []byte { return p.ReqID }
func (p *Ping) SetRequestID(id []byte) { p.ReqID = id }
func (*Pong) Name() string { return "PONG/v5" }
func (*Pong) Kind() byte { return PongMsg }
func (p *Pong) RequestID() []byte { return p.ReqID }
func (p *Pong) SetRequestID(id []byte) { p.ReqID = id }
func (*Findnode) Name() string { return "FINDNODE/v5" }
func (*Findnode) Kind() byte { return FindnodeMsg }
func (p *Findnode) RequestID() []byte { return p.ReqID }
func (p *Findnode) SetRequestID(id []byte) { p.ReqID = id }
func (*Nodes) Name() string { return "NODES/v5" }
func (*Nodes) Kind() byte { return NodesMsg }
func (p *Nodes) RequestID() []byte { return p.ReqID }
func (p *Nodes) SetRequestID(id []byte) { p.ReqID = id }
func (*TalkRequest) Name() string { return "TALKREQ/v5" }
func (*TalkRequest) Kind() byte { return TalkRequestMsg }
func (p *TalkRequest) RequestID() []byte { return p.ReqID }
func (p *TalkRequest) SetRequestID(id []byte) { p.ReqID = id }
func (*TalkResponse) Name() string { return "TALKRESP/v5" }
func (*TalkResponse) Kind() byte { return TalkResponseMsg }
func (p *TalkResponse) RequestID() []byte { return p.ReqID }
func (p *TalkResponse) SetRequestID(id []byte) { p.ReqID = id }
func (*RequestTicket) Name() string { return "REQTICKET/v5" }
func (*RequestTicket) Kind() byte { return RequestTicketMsg }
func (p *RequestTicket) RequestID() []byte { return p.ReqID }
func (p *RequestTicket) SetRequestID(id []byte) { p.ReqID = id }
func (*Regtopic) Name() string { return "REGTOPIC/v5" }
func (*Regtopic) Kind() byte { return RegtopicMsg }
func (p *Regtopic) RequestID() []byte { return p.ReqID }
func (p *Regtopic) SetRequestID(id []byte) { p.ReqID = id }
func (*Ticket) Name() string { return "TICKET/v5" }
func (*Ticket) Kind() byte { return TicketMsg }
func (p *Ticket) RequestID() []byte { return p.ReqID }
func (p *Ticket) SetRequestID(id []byte) { p.ReqID = id }
func (*Regconfirmation) Name() string { return "REGCONFIRMATION/v5" }
func (*Regconfirmation) Kind() byte { return RegconfirmationMsg }
func (p *Regconfirmation) RequestID() []byte { return p.ReqID }
func (p *Regconfirmation) SetRequestID(id []byte) { p.ReqID = id }
func (*TopicQuery) Name() string { return "TOPICQUERY/v5" }
func (*TopicQuery) Kind() byte { return TopicQueryMsg }
func (p *TopicQuery) RequestID() []byte { return p.ReqID }
func (p *TopicQuery) SetRequestID(id []byte) { p.ReqID = id }