// Copyright 2018 The dexon-consensus Authors
// This file is part of the dexon-consensus library.
//
// The dexon-consensus 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 dexon-consensus 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 dexon-consensus library. If not, see
// <http://www.gnu.org/licenses/>.
package dex
import (
"crypto/ecdsa"
"encoding/hex"
"fmt"
"math/big"
"strconv"
"strings"
"github.com/dexon-foundation/dexon/accounts/abi"
"github.com/dexon-foundation/dexon/common"
"github.com/dexon-foundation/dexon/core/types"
"github.com/dexon-foundation/dexon/crypto"
"github.com/dexon-foundation/dexon/params"
"github.com/dexon-foundation/dexon/rlp"
"github.com/onrik/ethrpc"
)
const numConfirmation = 1
const recoveryABI = `
[
{
"constant": true,
"inputs": [
{
"name": "",
"type": "uint256"
},
{
"name": "",
"type": "address"
}
],
"name": "voted",
"outputs": [
{
"name": "",
"type": "bool"
}
],
"payable": false,
"stateMutability": "view",
"type": "function"
},
{
"constant": false,
"inputs": [],
"name": "renounceOwnership",
"outputs": [],
"payable": false,
"stateMutability": "nonpayable",
"type": "function"
},
{
"constant": true,
"inputs": [],
"name": "owner",
"outputs": [
{
"name": "",
"type": "address"
}
],
"payable": false,
"stateMutability": "view",
"type": "function"
},
{
"constant": true,
"inputs": [],
"name": "isOwner",
"outputs": [
{
"name": "",
"type": "bool"
}
],
"payable": false,
"stateMutability": "view",
"type": "function"
},
{
"constant": true,
"inputs": [],
"name": "depositValue",
"outputs": [
{
"name": "",
"type": "uint256"
}
],
"payable": false,
"stateMutability": "view",
"type": "function"
},
{
"constant": true,
"inputs": [
{
"name": "",
"type": "uint256"
},
{
"name": "",
"type": "uint256"
}
],
"name": "votes",
"outputs": [
{
"name": "",
"type": "address"
}
],
"payable": false,
"stateMutability": "view",
"type": "function"
},
{
"constant": true,
"inputs": [
{
"name": "",
"type": "address"
}
],
"name": "withdrawable",
"outputs": [
{
"name": "",
"type": "uint256"
}
],
"payable": false,
"stateMutability": "view",
"type": "function"
},
{
"constant": false,
"inputs": [
{
"name": "newOwner",
"type": "address"
}
],
"name": "transferOwnership",
"outputs": [],
"payable": false,
"stateMutability": "nonpayable",
"type": "function"
},
{
"anonymous": false,
"inputs": [
{
"indexed": true,
"name": "height",
"type": "uint256"
},
{
"indexed": false,
"name": "voter",
"type": "address"
}
],
"name": "VotedForRecovery",
"type": "event"
},
{
"anonymous": false,
"inputs": [
{
"indexed": true,
"name": "owner",
"type": "address"
},
{
"indexed": false,
"name": "amount",
"type": "uint256"
}
],
"name": "Withdrawn",
"type": "event"
},
{
"anonymous": false,
"inputs": [
{
"indexed": true,
"name": "previousOwner",
"type": "address"
},
{
"indexed": true,
"name": "newOwner",
"type": "address"
}
],
"name": "OwnershipTransferred",
"type": "event"
},
{
"constant": false,
"inputs": [
{
"name": "DepositValue",
"type": "uint256"
}
],
"name": "setDeposit",
"outputs": [],
"payable": false,
"stateMutability": "nonpayable",
"type": "function"
},
{
"constant": false,
"inputs": [
{
"name": "height",
"type": "uint256"
},
{
"name": "value",
"type": "uint256"
}
],
"name": "refund",
"outputs": [],
"payable": false,
"stateMutability": "nonpayable",
"type": "function"
},
{
"constant": false,
"inputs": [],
"name": "withdraw",
"outputs": [],
"payable": false,
"stateMutability": "nonpayable",
"type": "function"
},
{
"constant": false,
"inputs": [
{
"name": "height",
"type": "uint256"
}
],
"name": "voteForSkipBlock",
"outputs": [],
"payable": true,
"stateMutability": "payable",
"type": "function"
},
{
"constant": false,
"inputs": [
{
"name": "height",
"type": "uint256"
}
],
"name": "numVotes",
"outputs": [
{
"name": "",
"type": "uint256"
}
],
"payable": false,
"stateMutability": "nonpayable",
"type": "function"
}
]
`
var abiObject abi.ABI
func init() {
var err error
abiObject, err = abi.JSON(strings.NewReader(recoveryABI))
if err != nil {
panic(err)
}
}
type Recovery struct {
gov *DexconGovernance
contract common.Address
confirmation int
privateKey *ecdsa.PrivateKey
nodeAddress common.Address
client *ethrpc.EthRPC
}
func NewRecovery(config *params.RecoveryConfig, networkRPC string,
gov *DexconGovernance, privKey *ecdsa.PrivateKey) *Recovery {
client := ethrpc.New(networkRPC)
return &Recovery{
gov: gov,
contract: config.Contract,
confirmation: config.Confirmation,
privateKey: privKey,
nodeAddress: crypto.PubkeyToAddress(privKey.PublicKey),
client: client,
}
}
func (r *Recovery) genVoteForSkipBlockTx(height uint64) (*types.Transaction, error) {
netVersion, err := r.client.NetVersion()
if err != nil {
return nil, err
}
networkID, err := strconv.Atoi(netVersion)
if err != nil {
return nil, err
}
data, err := abiObject.Pack("depositValue")
if err != nil {
return nil, err
}
res, err := r.client.EthCall(ethrpc.T{
From: r.nodeAddress.String(),
To: r.contract.String(),
Data: "0x" + hex.EncodeToString(data),
}, "latest")
if err != nil {
return nil, err
}
resBytes, err := hex.DecodeString(res[2:])
if err != nil {
return nil, err
}
var depositValue *big.Int
err = abiObject.Unpack(&depositValue, "depositValue", resBytes)
if err != nil {
return nil, err
}
data, err = abiObject.Pack("voteForSkipBlock", new(big.Int).SetUint64(height))
if err != nil {
return nil, err
}
gasPrice, err := r.client.EthGasPrice()
if err != nil {
return nil, err
}
nonce, err := r.client.EthGetTransactionCount(r.nodeAddress.String(), "pending")
if err != nil {
return nil, err
}
// Increase gasPrice to 3 times of suggested gas price to make sure it will
// be included in time.
useGasPrice := new(big.Int).Mul(&gasPrice, big.NewInt(3))
tx := types.NewTransaction(
uint64(nonce),
r.contract,
depositValue,
uint64(100000),
useGasPrice,
data)
signer := types.NewEIP155Signer(big.NewInt(int64(networkID)))
return types.SignTx(tx, signer, r.privateKey)
}
func (r *Recovery) ProposeSkipBlock(height uint64) error {
tx, err := r.genVoteForSkipBlockTx(height)
if err != nil {
return err
}
txData, err := rlp.EncodeToBytes(tx)
if err != nil {
return err
}
_, err = r.client.EthSendRawTransaction("0x" + hex.EncodeToString(txData))
return err
}
func (r *Recovery) Votes(height uint64) (uint64, error) {
data, err := abiObject.Pack("numVotes", new(big.Int).SetUint64(height))
if err != nil {
return 0, err
}
bn, err := r.client.EthBlockNumber()
if err != nil {
return 0, err
}
snapshotHeight := bn - numConfirmation
res, err := r.client.EthCall(ethrpc.T{
From: r.nodeAddress.String(),
To: r.contract.String(),
Data: "0x" + hex.EncodeToString(data),
}, fmt.Sprintf("0x%x", snapshotHeight))
if err != nil {
return 0, err
}
resBytes, err := hex.DecodeString(res[2:])
if err != nil {
return 0, err
}
votes := new(big.Int)
err = abiObject.Unpack(&votes, "numVotes", resBytes)
if err != nil {
return 0, err
}
notarySet, err := r.gov.NotarySetAddresses(r.gov.Round())
if err != nil {
return 0, err
}
count := uint64(0)
for i := uint64(0); i < votes.Uint64(); i++ {
data, err = abiObject.Pack(
"votes", new(big.Int).SetUint64(height), new(big.Int).SetUint64(i))
if err != nil {
return 0, err
}
res, err = r.client.EthCall(ethrpc.T{
From: r.nodeAddress.String(),
To: r.contract.String(),
Data: "0x" + hex.EncodeToString(data),
}, fmt.Sprintf("0x%x", snapshotHeight))
if err != nil {
return 0, err
}
resBytes, err := hex.DecodeString(res[2:])
if err != nil {
return 0, err
}
var addr common.Address
err = abiObject.Unpack(&addr, "votes", resBytes)
if err != nil {
return 0, err
}
if _, ok := notarySet[addr]; ok {
count += 1
}
}
return count, nil
}