neo-go/pkg/core/native/designate.go
2021-01-14 17:52:09 +03:00

283 lines
7.2 KiB
Go

package native
import (
"encoding/binary"
"errors"
"math"
"sort"
"sync/atomic"
"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/native/nativenames"
"github.com/nspcc-dev/neo-go/pkg/core/state"
"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
"github.com/nspcc-dev/neo-go/pkg/io"
"github.com/nspcc-dev/neo-go/pkg/smartcontract"
"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
"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"
)
// Designate represents designation contract.
type Designate struct {
interop.ContractMD
NEO *NEO
rolesChangedFlag atomic.Value
oracles atomic.Value
// p2pSigExtensionsEnabled defines whether the P2P signature extensions logic is relevant.
p2pSigExtensionsEnabled bool
}
type oraclesData struct {
nodes keys.PublicKeys
addr util.Uint160
height uint32
}
const (
designateContractID = -4
// maxNodeCount is the maximum number of nodes to set the role for.
maxNodeCount = 32
)
// Role represents type of participant.
type Role byte
// Role enumeration.
const (
RoleStateValidator Role = 4
RoleOracle Role = 8
RoleP2PNotary Role = 128
)
// Various errors.
var (
ErrAlreadyDesignated = errors.New("already designated given role at current block")
ErrEmptyNodeList = errors.New("node list is empty")
ErrInvalidIndex = errors.New("invalid index")
ErrInvalidRole = errors.New("invalid role")
ErrLargeNodeList = errors.New("node list is too large")
ErrNoBlock = errors.New("no persisting block in the context")
)
func (s *Designate) isValidRole(r Role) bool {
return r == RoleOracle || r == RoleStateValidator || (s.p2pSigExtensionsEnabled && r == RoleP2PNotary)
}
func newDesignate(p2pSigExtensionsEnabled bool) *Designate {
s := &Designate{ContractMD: *interop.NewContractMD(nativenames.Designation)}
s.ContractID = designateContractID
s.p2pSigExtensionsEnabled = p2pSigExtensionsEnabled
desc := newDescriptor("getDesignatedByRole", smartcontract.ArrayType,
manifest.NewParameter("role", smartcontract.IntegerType),
manifest.NewParameter("index", smartcontract.IntegerType))
md := newMethodAndPrice(s.getDesignatedByRole, 1000000, callflag.ReadStates)
s.AddMethod(md, desc)
desc = newDescriptor("designateAsRole", smartcontract.VoidType,
manifest.NewParameter("role", smartcontract.IntegerType),
manifest.NewParameter("nodes", smartcontract.ArrayType))
md = newMethodAndPrice(s.designateAsRole, 0, callflag.WriteStates)
s.AddMethod(md, desc)
return s
}
// Initialize initializes Oracle contract.
func (s *Designate) Initialize(ic *interop.Context) error {
return nil
}
// OnPersist implements Contract interface.
func (s *Designate) OnPersist(ic *interop.Context) error {
return nil
}
// PostPersist implements Contract interface.
func (s *Designate) PostPersist(ic *interop.Context) error {
if !s.rolesChanged() {
return nil
}
nodeKeys, height, err := s.GetDesignatedByRole(ic.DAO, RoleOracle, math.MaxUint32)
if err != nil {
return err
}
od := &oraclesData{
nodes: nodeKeys,
addr: oracleHashFromNodes(nodeKeys),
height: height,
}
s.oracles.Store(od)
s.rolesChangedFlag.Store(false)
return nil
}
// Metadata returns contract metadata.
func (s *Designate) Metadata() *interop.ContractMD {
return &s.ContractMD
}
func (s *Designate) getDesignatedByRole(ic *interop.Context, args []stackitem.Item) stackitem.Item {
r, ok := s.getRole(args[0])
if !ok {
panic(ErrInvalidRole)
}
ind, err := args[1].TryInteger()
if err != nil || !ind.IsUint64() {
panic(ErrInvalidIndex)
}
index := ind.Uint64()
if index > uint64(ic.Chain.BlockHeight()+1) {
panic(ErrInvalidIndex)
}
pubs, _, err := s.GetDesignatedByRole(ic.DAO, r, uint32(index))
if err != nil {
panic(err)
}
return pubsToArray(pubs)
}
func (s *Designate) rolesChanged() bool {
rc := s.rolesChangedFlag.Load()
return rc == nil || rc.(bool)
}
func oracleHashFromNodes(nodes keys.PublicKeys) util.Uint160 {
if len(nodes) == 0 {
return util.Uint160{}
}
script, _ := smartcontract.CreateMajorityMultiSigRedeemScript(nodes.Copy())
return hash.Hash160(script)
}
func (s *Designate) getLastDesignatedHash(d dao.DAO, r Role) (util.Uint160, error) {
if !s.isValidRole(r) {
return util.Uint160{}, ErrInvalidRole
}
if r == RoleOracle && !s.rolesChanged() {
odVal := s.oracles.Load()
if odVal != nil {
od := odVal.(*oraclesData)
return od.addr, nil
}
}
nodes, _, err := s.GetDesignatedByRole(d, r, math.MaxUint32)
if err != nil {
return util.Uint160{}, err
}
// We only have hashing defined for oracles now.
return oracleHashFromNodes(nodes), nil
}
// GetDesignatedByRole returns nodes for role r.
func (s *Designate) GetDesignatedByRole(d dao.DAO, r Role, index uint32) (keys.PublicKeys, uint32, error) {
if !s.isValidRole(r) {
return nil, 0, ErrInvalidRole
}
if r == RoleOracle && !s.rolesChanged() {
odVal := s.oracles.Load()
if odVal != nil {
od := odVal.(*oraclesData)
if od.height <= index {
return od.nodes, od.height, nil
}
}
}
kvs, err := d.GetStorageItemsWithPrefix(s.ContractID, []byte{byte(r)})
if err != nil {
return nil, 0, err
}
var ns NodeList
var bestIndex uint32
var resSi *state.StorageItem
for k, si := range kvs {
if len(k) < 4 {
continue
}
siInd := binary.BigEndian.Uint32([]byte(k))
if (resSi == nil || siInd > bestIndex) && siInd <= index {
bestIndex = siInd
resSi = si
}
}
if resSi != nil {
reader := io.NewBinReaderFromBuf(resSi.Value)
ns.DecodeBinary(reader)
if reader.Err != nil {
return nil, 0, reader.Err
}
}
return keys.PublicKeys(ns), bestIndex, err
}
func (s *Designate) designateAsRole(ic *interop.Context, args []stackitem.Item) stackitem.Item {
r, ok := s.getRole(args[0])
if !ok {
panic(ErrInvalidRole)
}
var ns NodeList
if err := ns.fromStackItem(args[1]); err != nil {
panic(err)
}
err := s.DesignateAsRole(ic, r, keys.PublicKeys(ns))
if err != nil {
panic(err)
}
return pubsToArray(keys.PublicKeys(ns))
}
// DesignateAsRole sets nodes for role r.
func (s *Designate) DesignateAsRole(ic *interop.Context, r Role, pubs keys.PublicKeys) error {
length := len(pubs)
if length == 0 {
return ErrEmptyNodeList
}
if length > maxNodeCount {
return ErrLargeNodeList
}
if !s.isValidRole(r) {
return ErrInvalidRole
}
h := s.NEO.GetCommitteeAddress()
if ok, err := runtime.CheckHashedWitness(ic, h); err != nil || !ok {
return ErrInvalidWitness
}
if ic.Block == nil {
return ErrNoBlock
}
var key = make([]byte, 5)
key[0] = byte(r)
binary.BigEndian.PutUint32(key[1:], ic.Block.Index+1)
si := ic.DAO.GetStorageItem(s.ContractID, key)
if si != nil {
return ErrAlreadyDesignated
}
sort.Sort(pubs)
s.rolesChangedFlag.Store(true)
si = &state.StorageItem{Value: NodeList(pubs).Bytes()}
return ic.DAO.PutStorageItem(s.ContractID, key, si)
}
func (s *Designate) getRole(item stackitem.Item) (Role, bool) {
bi, err := item.TryInteger()
if err != nil {
return 0, false
}
if !bi.IsUint64() {
return 0, false
}
u := bi.Uint64()
return Role(u), u <= math.MaxUint8 && s.isValidRole(Role(u))
}