neo-go/pkg/core/native/native_neo.go
Roman Khimov c16040aecc native: sort GetValidators result
As it's returned sorted now. Fixes state change mismatch for
NextValidators. It also partially reverts
2f8e7e4d33 and significantly changes the test
chain as the fees are no longer being sent to the same account.
2020-08-10 19:49:09 +03:00

543 lines
16 KiB
Go

package native
import (
"crypto/elliptic"
"errors"
"math/big"
"sort"
"strings"
"sync/atomic"
"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
"github.com/nspcc-dev/neo-go/pkg/core/dao"
"github.com/nspcc-dev/neo-go/pkg/core/interop"
"github.com/nspcc-dev/neo-go/pkg/core/interop/runtime"
"github.com/nspcc-dev/neo-go/pkg/core/state"
"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
"github.com/nspcc-dev/neo-go/pkg/encoding/bigint"
"github.com/nspcc-dev/neo-go/pkg/smartcontract"
"github.com/nspcc-dev/neo-go/pkg/smartcontract/manifest"
"github.com/nspcc-dev/neo-go/pkg/util"
"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
)
// NEO represents NEO native contract.
type NEO struct {
nep5TokenNative
GAS *GAS
validators atomic.Value
}
// keyWithVotes is a serialized key with votes balance. It's not deserialized
// because some uses of it imply serialized-only usage and converting to
// PublicKey is quite expensive.
type keyWithVotes struct {
Key string
Votes *big.Int
}
const (
neoName = "NEO"
neoContractID = -1
// NEOTotalSupply is the total amount of NEO in the system.
NEOTotalSupply = 100000000
// prefixCandidate is a prefix used to store validator's data.
prefixCandidate = 33
// prefixVotersCount is a prefix for storing total amount of NEO of voters.
prefixVotersCount = 1
// effectiveVoterTurnout represents minimal ratio of total supply to total amount voted value
// which is require to use non-standby validators.
effectiveVoterTurnout = 5
)
var (
// nextValidatorsKey is a key used to store validators for the
// next block.
nextValidatorsKey = []byte{14}
)
// makeValidatorKey creates a key from account script hash.
func makeValidatorKey(key *keys.PublicKey) []byte {
b := key.Bytes()
// Don't create a new buffer.
b = append(b, 0)
copy(b[1:], b[0:])
b[0] = prefixCandidate
return b
}
// NewNEO returns NEO native contract.
func NewNEO() *NEO {
n := &NEO{}
nep5 := newNEP5Native(neoName)
nep5.symbol = "neo"
nep5.decimals = 0
nep5.factor = 1
nep5.onPersist = chainOnPersist(nep5.OnPersist, n.OnPersist)
nep5.incBalance = n.increaseBalance
nep5.ContractID = neoContractID
n.nep5TokenNative = *nep5
n.validators.Store(keys.PublicKeys(nil))
onp := n.Methods["onPersist"]
onp.Func = getOnPersistWrapper(n.onPersist)
n.Methods["onPersist"] = onp
desc := newDescriptor("unclaimedGas", smartcontract.IntegerType,
manifest.NewParameter("account", smartcontract.Hash160Type),
manifest.NewParameter("end", smartcontract.IntegerType))
md := newMethodAndPrice(n.unclaimedGas, 3000000, smartcontract.AllowStates)
n.AddMethod(md, desc, true)
desc = newDescriptor("registerCandidate", smartcontract.BoolType,
manifest.NewParameter("pubkey", smartcontract.PublicKeyType))
md = newMethodAndPrice(n.registerCandidate, 5000000, smartcontract.AllowModifyStates)
n.AddMethod(md, desc, false)
desc = newDescriptor("unregisterCandidate", smartcontract.BoolType,
manifest.NewParameter("pubkey", smartcontract.PublicKeyType))
md = newMethodAndPrice(n.unregisterCandidate, 5000000, smartcontract.AllowModifyStates)
n.AddMethod(md, desc, false)
desc = newDescriptor("vote", smartcontract.BoolType,
manifest.NewParameter("account", smartcontract.Hash160Type),
manifest.NewParameter("pubkey", smartcontract.PublicKeyType))
md = newMethodAndPrice(n.vote, 500000000, smartcontract.AllowModifyStates)
n.AddMethod(md, desc, false)
desc = newDescriptor("getCandidates", smartcontract.ArrayType)
md = newMethodAndPrice(n.getCandidatesCall, 100000000, smartcontract.AllowStates)
n.AddMethod(md, desc, true)
desc = newDescriptor("getСommittee", smartcontract.ArrayType)
md = newMethodAndPrice(n.getCommittee, 100000000, smartcontract.AllowStates)
n.AddMethod(md, desc, true)
desc = newDescriptor("getValidators", smartcontract.ArrayType)
md = newMethodAndPrice(n.getValidators, 100000000, smartcontract.AllowStates)
n.AddMethod(md, desc, true)
desc = newDescriptor("getNextBlockValidators", smartcontract.ArrayType)
md = newMethodAndPrice(n.getNextBlockValidators, 100000000, smartcontract.AllowStates)
n.AddMethod(md, desc, true)
return n
}
// Initialize initializes NEO contract.
func (n *NEO) Initialize(ic *interop.Context) error {
if err := n.nep5TokenNative.Initialize(ic); err != nil {
return err
}
if n.nep5TokenNative.getTotalSupply(ic.DAO).Sign() != 0 {
return errors.New("already initialized")
}
h, err := getStandbyValidatorsHash(ic)
if err != nil {
return err
}
n.mint(ic, h, big.NewInt(NEOTotalSupply))
err = ic.DAO.PutStorageItem(n.ContractID, []byte{prefixVotersCount}, &state.StorageItem{Value: []byte{}})
if err != nil {
return err
}
return nil
}
// OnPersist implements Contract interface.
func (n *NEO) OnPersist(ic *interop.Context) error {
pubs, err := n.GetValidatorsInternal(ic.Chain, ic.DAO)
if err != nil {
return err
}
si := new(state.StorageItem)
si.Value = pubs.Bytes()
return ic.DAO.PutStorageItem(n.ContractID, nextValidatorsKey, si)
}
func (n *NEO) increaseBalance(ic *interop.Context, h util.Uint160, si *state.StorageItem, amount *big.Int) error {
acc, err := state.NEOBalanceStateFromBytes(si.Value)
if err != nil {
return err
}
if amount.Sign() == -1 && acc.Balance.Cmp(new(big.Int).Neg(amount)) == -1 {
return errors.New("insufficient funds")
}
if err := n.distributeGas(ic, h, acc); err != nil {
return err
}
if amount.Sign() == 0 {
si.Value = acc.Bytes()
return nil
}
if err := n.ModifyAccountVotes(acc, ic.DAO, amount, modifyVoteTransfer); err != nil {
return err
}
if acc.VoteTo != nil {
if err := n.modifyVoterTurnout(ic.DAO, amount); err != nil {
return err
}
}
acc.Balance.Add(&acc.Balance, amount)
if acc.Balance.Sign() != 0 {
si.Value = acc.Bytes()
} else {
si.Value = nil
}
return nil
}
func (n *NEO) distributeGas(ic *interop.Context, h util.Uint160, acc *state.NEOBalanceState) error {
if ic.Block == nil || ic.Block.Index == 0 {
return nil
}
gen := ic.Chain.CalculateClaimable(&acc.Balance, acc.BalanceHeight, ic.Block.Index)
acc.BalanceHeight = ic.Block.Index
n.GAS.mint(ic, h, gen)
return nil
}
func (n *NEO) unclaimedGas(ic *interop.Context, args []stackitem.Item) stackitem.Item {
u := toUint160(args[0])
end := uint32(toBigInt(args[1]).Int64())
bs, err := ic.DAO.GetNEP5Balances(u)
if err != nil {
panic(err)
}
tr := bs.Trackers[n.ContractID]
gen := ic.Chain.CalculateClaimable(&tr.Balance, tr.LastUpdatedBlock, end)
return stackitem.NewBigInteger(gen)
}
func (n *NEO) registerCandidate(ic *interop.Context, args []stackitem.Item) stackitem.Item {
pub := toPublicKey(args[0])
ok, err := runtime.CheckKeyedWitness(ic, pub)
if err != nil {
panic(err)
} else if !ok {
return stackitem.NewBool(false)
}
err = n.RegisterCandidateInternal(ic, pub)
return stackitem.NewBool(err == nil)
}
// RegisterCandidateInternal registers pub as a new candidate.
func (n *NEO) RegisterCandidateInternal(ic *interop.Context, pub *keys.PublicKey) error {
key := makeValidatorKey(pub)
si := ic.DAO.GetStorageItem(n.ContractID, key)
if si == nil {
c := &candidate{Registered: true}
si = &state.StorageItem{Value: c.Bytes()}
} else {
c := new(candidate).FromBytes(si.Value)
c.Registered = true
si.Value = c.Bytes()
}
return ic.DAO.PutStorageItem(n.ContractID, key, si)
}
func (n *NEO) unregisterCandidate(ic *interop.Context, args []stackitem.Item) stackitem.Item {
pub := toPublicKey(args[0])
ok, err := runtime.CheckKeyedWitness(ic, pub)
if err != nil {
panic(err)
} else if !ok {
return stackitem.NewBool(false)
}
err = n.UnregisterCandidateInternal(ic, pub)
return stackitem.NewBool(err == nil)
}
// UnregisterCandidateInternal unregisters pub as a candidate.
func (n *NEO) UnregisterCandidateInternal(ic *interop.Context, pub *keys.PublicKey) error {
key := makeValidatorKey(pub)
si := ic.DAO.GetStorageItem(n.ContractID, key)
if si == nil {
return nil
}
n.validators.Store(keys.PublicKeys(nil))
c := new(candidate).FromBytes(si.Value)
if c.Votes.Sign() == 0 {
return ic.DAO.DeleteStorageItem(n.ContractID, key)
}
c.Registered = false
si.Value = c.Bytes()
return ic.DAO.PutStorageItem(n.ContractID, key, si)
}
func (n *NEO) vote(ic *interop.Context, args []stackitem.Item) stackitem.Item {
acc := toUint160(args[0])
var pub *keys.PublicKey
if _, ok := args[1].(stackitem.Null); !ok {
pub = toPublicKey(args[1])
}
err := n.VoteInternal(ic, acc, pub)
return stackitem.NewBool(err == nil)
}
// VoteInternal votes from account h for validarors specified in pubs.
func (n *NEO) VoteInternal(ic *interop.Context, h util.Uint160, pub *keys.PublicKey) error {
ok, err := runtime.CheckHashedWitness(ic, h)
if err != nil {
return err
} else if !ok {
return errors.New("invalid signature")
}
key := makeAccountKey(h)
si := ic.DAO.GetStorageItem(n.ContractID, key)
if si == nil {
return errors.New("invalid account")
}
acc, err := state.NEOBalanceStateFromBytes(si.Value)
if err != nil {
return err
}
if (acc.VoteTo == nil) != (pub == nil) {
val := &acc.Balance
if pub == nil {
val = new(big.Int).Neg(val)
}
if err := n.modifyVoterTurnout(ic.DAO, val); err != nil {
return err
}
}
if err := n.ModifyAccountVotes(acc, ic.DAO, new(big.Int).Neg(&acc.Balance), modifyVoteOld); err != nil {
return err
}
acc.VoteTo = pub
if err := n.ModifyAccountVotes(acc, ic.DAO, &acc.Balance, modifyVoteNew); err != nil {
return err
}
si.Value = acc.Bytes()
return ic.DAO.PutStorageItem(n.ContractID, key, si)
}
const (
modifyVoteTransfer = iota
modifyVoteOld
modifyVoteNew
)
// ModifyAccountVotes modifies votes of the specified account by value (can be negative).
// typ specifies if this modify is occuring during transfer or vote (with old or new validator).
func (n *NEO) ModifyAccountVotes(acc *state.NEOBalanceState, d dao.DAO, value *big.Int, typ int) error {
if acc.VoteTo != nil {
key := makeValidatorKey(acc.VoteTo)
si := d.GetStorageItem(n.ContractID, key)
if si == nil {
return errors.New("invalid validator")
}
cd := new(candidate).FromBytes(si.Value)
cd.Votes.Add(&cd.Votes, value)
switch typ {
case modifyVoteOld:
if !cd.Registered && cd.Votes.Sign() == 0 {
return d.DeleteStorageItem(n.ContractID, key)
}
case modifyVoteNew:
if !cd.Registered {
return errors.New("validator must be registered")
}
}
n.validators.Store(keys.PublicKeys(nil))
si.Value = cd.Bytes()
return d.PutStorageItem(n.ContractID, key, si)
}
return nil
}
func (n *NEO) getCandidates(d dao.DAO) ([]keyWithVotes, error) {
siMap, err := d.GetStorageItemsWithPrefix(n.ContractID, []byte{prefixCandidate})
if err != nil {
return nil, err
}
arr := make([]keyWithVotes, 0, len(siMap))
for key, si := range siMap {
c := new(candidate).FromBytes(si.Value)
if c.Registered {
arr = append(arr, keyWithVotes{key, &c.Votes})
}
}
sort.Slice(arr, func(i, j int) bool { return strings.Compare(arr[i].Key, arr[j].Key) == -1 })
return arr, nil
}
// GetCandidates returns current registered validators list with keys
// and votes.
func (n *NEO) GetCandidates(d dao.DAO) ([]state.Validator, error) {
kvs, err := n.getCandidates(d)
if err != nil {
return nil, err
}
arr := make([]state.Validator, len(kvs))
for i := range kvs {
arr[i].Key, err = keys.NewPublicKeyFromBytes([]byte(kvs[i].Key), elliptic.P256())
if err != nil {
return nil, err
}
arr[i].Votes = kvs[i].Votes
}
return arr, nil
}
func (n *NEO) getCandidatesCall(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
validators, err := n.getCandidates(ic.DAO)
if err != nil {
panic(err)
}
arr := make([]stackitem.Item, len(validators))
for i := range validators {
arr[i] = stackitem.NewStruct([]stackitem.Item{
stackitem.NewByteArray([]byte(validators[i].Key)),
stackitem.NewBigInteger(validators[i].Votes),
})
}
return stackitem.NewArray(arr)
}
// GetValidatorsInternal returns a list of current validators.
func (n *NEO) GetValidatorsInternal(bc blockchainer.Blockchainer, d dao.DAO) (keys.PublicKeys, error) {
if vals := n.validators.Load().(keys.PublicKeys); vals != nil {
return vals.Copy(), nil
}
result, err := n.getCommitteeMembers(bc, d)
if err != nil {
return nil, err
}
count := bc.GetConfig().ValidatorsCount
if len(result) < count {
count = len(result)
}
result = result[:count]
sort.Sort(result)
n.validators.Store(result)
return result, nil
}
func (n *NEO) getValidators(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
result, err := n.GetValidatorsInternal(ic.Chain, ic.DAO)
if err != nil {
panic(err)
}
return pubsToArray(result)
}
func (n *NEO) getCommittee(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
pubs, err := n.getCommitteeMembers(ic.Chain, ic.DAO)
if err != nil {
panic(err)
}
sort.Sort(pubs)
return pubsToArray(pubs)
}
func (n *NEO) modifyVoterTurnout(d dao.DAO, amount *big.Int) error {
key := []byte{prefixVotersCount}
si := d.GetStorageItem(n.ContractID, key)
if si == nil {
return errors.New("voters count not found")
}
votersCount := bigint.FromBytes(si.Value)
votersCount.Add(votersCount, amount)
si.Value = bigint.ToBytes(votersCount)
return d.PutStorageItem(n.ContractID, key, si)
}
func (n *NEO) getCommitteeMembers(bc blockchainer.Blockchainer, d dao.DAO) (keys.PublicKeys, error) {
key := []byte{prefixVotersCount}
si := d.GetStorageItem(n.ContractID, key)
if si == nil {
return nil, errors.New("voters count not found")
}
votersCount := bigint.FromBytes(si.Value)
// votersCount / totalSupply must be >= 0.2
votersCount.Mul(votersCount, big.NewInt(effectiveVoterTurnout))
voterTurnout := votersCount.Div(votersCount, n.getTotalSupply(d))
if voterTurnout.Sign() != 1 {
return bc.GetStandByValidators(), nil
}
cs, err := n.getCandidates(d)
if err != nil {
return nil, err
}
sbVals := bc.GetStandByValidators()
count := len(sbVals)
if len(cs) < count {
return sbVals, nil
}
sort.Slice(cs, func(i, j int) bool {
// The most-voted validators should end up in the front of the list.
cmp := cs[i].Votes.Cmp(cs[j].Votes)
if cmp != 0 {
return cmp > 0
}
// Ties are broken with public keys.
return strings.Compare(cs[i].Key, cs[j].Key) == -1
})
pubs := make(keys.PublicKeys, count)
for i := range pubs {
pubs[i], err = keys.NewPublicKeyFromBytes([]byte(cs[i].Key), elliptic.P256())
if err != nil {
return nil, err
}
}
return pubs, nil
}
func (n *NEO) getNextBlockValidators(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
result, err := n.getNextBlockValidatorsInternal(ic.Chain, ic.DAO)
if err != nil {
panic(err)
}
return pubsToArray(result)
}
// GetNextBlockValidatorsInternal returns next block validators.
func (n *NEO) GetNextBlockValidatorsInternal(bc blockchainer.Blockchainer, d dao.DAO) (keys.PublicKeys, error) {
pubs, err := n.getNextBlockValidatorsInternal(bc, d)
if err != nil {
return nil, err
}
return pubs.Copy(), nil
}
// getNextBlockValidatorsInternal returns next block validators.
func (n *NEO) getNextBlockValidatorsInternal(bc blockchainer.Blockchainer, d dao.DAO) (keys.PublicKeys, error) {
si := d.GetStorageItem(n.ContractID, nextValidatorsKey)
if si == nil {
return n.GetValidatorsInternal(bc, d)
}
pubs := keys.PublicKeys{}
err := pubs.DecodeBytes(si.Value)
if err != nil {
return nil, err
}
return pubs, nil
}
func pubsToArray(pubs keys.PublicKeys) stackitem.Item {
arr := make([]stackitem.Item, len(pubs))
for i := range pubs {
arr[i] = stackitem.NewByteArray(pubs[i].Bytes())
}
return stackitem.NewArray(arr)
}
func toPublicKey(s stackitem.Item) *keys.PublicKey {
buf, err := s.TryBytes()
if err != nil {
panic(err)
}
pub := new(keys.PublicKey)
if err := pub.DecodeBytes(buf); err != nil {
panic(err)
}
return pub
}