// Copyright 2014 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 eth
import (
"fmt"
"io"
"math/big"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/event"
"github.com/ethereum/go-ethereum/rlp"
)
// Constants to match up protocol versions and messages
const (
eth62 = 62
eth63 = 63
)
// protocolName is the official short name of the protocol used during capability negotiation.
const protocolName = "eth"
// ProtocolVersions are the supported versions of the eth protocol (first is primary).
var ProtocolVersions = []uint{eth63}
// protocolLengths are the number of implemented message corresponding to different protocol versions.
var protocolLengths = map[uint]uint64{eth63: 17, eth62: 8}
const protocolMaxMsgSize = 10 * 1024 * 1024 // Maximum cap on the size of a protocol message
// eth protocol message codes
const (
// Protocol messages belonging to eth/62
StatusMsg = 0x00
NewBlockHashesMsg = 0x01
TxMsg = 0x02
GetBlockHeadersMsg = 0x03
BlockHeadersMsg = 0x04
GetBlockBodiesMsg = 0x05
BlockBodiesMsg = 0x06
NewBlockMsg = 0x07
// Protocol messages belonging to eth/63
GetNodeDataMsg = 0x0d
NodeDataMsg = 0x0e
GetReceiptsMsg = 0x0f
ReceiptsMsg = 0x10
)
type errCode int
const (
ErrMsgTooLarge = iota
ErrDecode
ErrInvalidMsgCode
ErrProtocolVersionMismatch
ErrNetworkIdMismatch
ErrGenesisBlockMismatch
ErrNoStatusMsg
ErrExtraStatusMsg
ErrSuspendedPeer
)
func (e errCode) String() string {
return errorToString[int(e)]
}
// XXX change once legacy code is out
var errorToString = map[int]string{
ErrMsgTooLarge: "Message too long",
ErrDecode: "Invalid message",
ErrInvalidMsgCode: "Invalid message code",
ErrProtocolVersionMismatch: "Protocol version mismatch",
ErrNetworkIdMismatch: "NetworkId mismatch",
ErrGenesisBlockMismatch: "Genesis block mismatch",
ErrNoStatusMsg: "No status message",
ErrExtraStatusMsg: "Extra status message",
ErrSuspendedPeer: "Suspended peer",
}
type txPool interface {
// AddRemotes should add the given transactions to the pool.
AddRemotes([]*types.Transaction) []error
// Pending should return pending transactions.
// The slice should be modifiable by the caller.
Pending() (map[common.Address]types.Transactions, error)
// SubscribeNewTxsEvent should return an event subscription of
// NewTxsEvent and send events to the given channel.
SubscribeNewTxsEvent(chan<- core.NewTxsEvent) event.Subscription
}
// statusData is the network packet for the status message.
type statusData struct {
ProtocolVersion uint32
NetworkId uint64
TD *big.Int
CurrentBlock common.Hash
GenesisBlock common.Hash
}
// newBlockHashesData is the network packet for the block announcements.
type newBlockHashesData []struct {
Hash common.Hash // Hash of one particular block being announced
Number uint64 // Number of one particular block being announced
}
// getBlockHeadersData represents a block header query.
type getBlockHeadersData struct {
Origin hashOrNumber // Block from which to retrieve headers
Amount uint64 // Maximum number of headers to retrieve
Skip uint64 // Blocks to skip between consecutive headers
Reverse bool // Query direction (false = rising towards latest, true = falling towards genesis)
}
// hashOrNumber is a combined field for specifying an origin block.
type hashOrNumber struct {
Hash common.Hash // Block hash from which to retrieve headers (excludes Number)
Number uint64 // Block hash from which to retrieve headers (excludes Hash)
}
// EncodeRLP is a specialized encoder for hashOrNumber to encode only one of the
// two contained union fields.
func (hn *hashOrNumber) EncodeRLP(w io.Writer) error {
if hn.Hash == (common.Hash{}) {
return rlp.Encode(w, hn.Number)
}
if hn.Number != 0 {
return fmt.Errorf("both origin hash (%x) and number (%d) provided", hn.Hash, hn.Number)
}
return rlp.Encode(w, hn.Hash)
}
// DecodeRLP is a specialized decoder for hashOrNumber to decode the contents
// into either a block hash or a block number.
func (hn *hashOrNumber) DecodeRLP(s *rlp.Stream) error {
_, size, _ := s.Kind()
origin, err := s.Raw()
if err == nil {
switch {
case size == 32:
err = rlp.DecodeBytes(origin, &hn.Hash)
case size <= 8:
err = rlp.DecodeBytes(origin, &hn.Number)
default:
err = fmt.Errorf("invalid input size %d for origin", size)
}
}
return err
}
// newBlockData is the network packet for the block propagation message.
type newBlockData struct {
Block *types.Block
TD *big.Int
}
// sanityCheck verifies that the values are reasonable, as a DoS protection
func (request *newBlockData) sanityCheck() error {
if err := request.Block.SanityCheck(); err != nil {
return err
}
//TD at mainnet block #7753254 is 76 bits. If it becomes 100 million times
// larger, it will still fit within 100 bits
if tdlen := request.TD.BitLen(); tdlen > 100 {
return fmt.Errorf("too large block TD: bitlen %d", tdlen)
}
return nil
}
// blockBody represents the data content of a single block.
type blockBody struct {
Transactions []*types.Transaction // Transactions contained within a block
Uncles []*types.Header // Uncles contained within a block
}
// blockBodiesData is the network packet for block content distribution.
type blockBodiesData []*blockBody
