// Copyright 2016 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 les implements the Light Ethereum Subprotocol.
package les
import (
"fmt"
"io"
"math/big"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/rlp"
)
// Constants to match up protocol versions and messages
const (
lpv1 = 1
)
// Supported versions of the les protocol (first is primary).
var ProtocolVersions = []uint{lpv1}
// Number of implemented message corresponding to different protocol versions.
var ProtocolLengths = []uint64{15}
const (
NetworkId = 1
ProtocolMaxMsgSize = 10 * 1024 * 1024 // Maximum cap on the size of a protocol message
)
// les protocol message codes
const (
// Protocol messages belonging to LPV1
StatusMsg = 0x00
AnnounceMsg = 0x01
GetBlockHeadersMsg = 0x02
BlockHeadersMsg = 0x03
GetBlockBodiesMsg = 0x04
BlockBodiesMsg = 0x05
GetReceiptsMsg = 0x06
ReceiptsMsg = 0x07
GetProofsMsg = 0x08
ProofsMsg = 0x09
GetCodeMsg = 0x0a
CodeMsg = 0x0b
SendTxMsg = 0x0c
GetHeaderProofsMsg = 0x0d
HeaderProofsMsg = 0x0e
)
type errCode int
const (
ErrMsgTooLarge = iota
ErrDecode
ErrInvalidMsgCode
ErrProtocolVersionMismatch
ErrNetworkIdMismatch
ErrGenesisBlockMismatch
ErrNoStatusMsg
ErrExtraStatusMsg
ErrSuspendedPeer
ErrUselessPeer
ErrRequestRejected
ErrUnexpectedResponse
ErrInvalidResponse
ErrTooManyTimeouts
ErrHandshakeMissingKey
)
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",
ErrRequestRejected: "Request rejected",
ErrUnexpectedResponse: "Unexpected response",
ErrInvalidResponse: "Invalid response",
ErrTooManyTimeouts: "Too many request timeouts",
ErrHandshakeMissingKey: "Key missing from handshake message",
}
type chainManager interface {
GetBlockHashesFromHash(hash common.Hash, amount uint64) (hashes []common.Hash)
GetBlock(hash common.Hash) (block *types.Block)
Status() (td *big.Int, currentBlock common.Hash, genesisBlock common.Hash)
}
// announceData is the network packet for the block announcements.
type announceData struct {
Hash common.Hash // Hash of one particular block being announced
Number uint64 // Number of one particular block being announced
Td *big.Int // Total difficulty of one particular block being announced
ReorgDepth uint64
Update keyValueList
haveHeaders uint64 // we have the headers of the remote peer's chain up to this number
headKnown bool
requested bool
next *announceData
}
type blockInfo struct {
Hash common.Hash // Hash of one particular block being announced
Number uint64 // Number of one particular block being announced
Td *big.Int // Total difficulty of one particular block being announced
}
// getBlockHashesData is the network packet for the hash based hash retrieval.
type getBlockHashesData struct {
Hash common.Hash
Amount uint64
}
// 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
}
// blockBodiesData is the network packet for block content distribution.
type blockBodiesData []*types.Body
// CodeData is the network response packet for a node data retrieval.
type CodeData []struct {
Value []byte
}
type proofsData [][]rlp.RawValue
