package native import ( "encoding/binary" "errors" "math" "sort" "sync/atomic" "github.com/nspcc-dev/neo-go/pkg/core/blockchainer/services" "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 stateVals atomic.Value notaries atomic.Value // p2pSigExtensionsEnabled defines whether the P2P signature extensions logic is relevant. p2pSigExtensionsEnabled bool OracleService atomic.Value // NotaryService represents Notary node module. NotaryService atomic.Value } type roleData struct { nodes keys.PublicKeys addr util.Uint160 height uint32 } const ( designateContractID = -6 // 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, 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 } if err := s.updateCachedRoleData(&s.oracles, ic.DAO, RoleOracle); err != nil { return err } if err := s.updateCachedRoleData(&s.stateVals, ic.DAO, RoleStateValidator); err != nil { return err } if s.p2pSigExtensionsEnabled { if err := s.updateCachedRoleData(&s.notaries, ic.DAO, RoleP2PNotary); err != nil { return err } } 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 (s *Designate) hashFromNodes(r Role, nodes keys.PublicKeys) util.Uint160 { if len(nodes) == 0 { return util.Uint160{} } var script []byte switch r { case RoleOracle: script, _ = smartcontract.CreateDefaultMultiSigRedeemScript(nodes.Copy()) case RoleP2PNotary: script, _ = smartcontract.CreateMultiSigRedeemScript(1, nodes.Copy()) default: script, _ = smartcontract.CreateMajorityMultiSigRedeemScript(nodes.Copy()) } return hash.Hash160(script) } func (s *Designate) updateCachedRoleData(v *atomic.Value, d dao.DAO, r Role) error { nodeKeys, height, err := s.GetDesignatedByRole(d, r, math.MaxUint32) if err != nil { return err } v.Store(&roleData{ nodes: nodeKeys, addr: s.hashFromNodes(r, nodeKeys), height: height, }) switch r { case RoleOracle: if orc, _ := s.OracleService.Load().(services.Oracle); orc != nil { orc.UpdateOracleNodes(nodeKeys.Copy()) } case RoleP2PNotary: if ntr, _ := s.NotaryService.Load().(services.Notary); ntr != nil { ntr.UpdateNotaryNodes(nodeKeys.Copy()) } } return nil } func (s *Designate) getCachedRoleData(r Role) *roleData { var val interface{} switch r { case RoleOracle: val = s.oracles.Load() case RoleStateValidator: val = s.stateVals.Load() case RoleP2PNotary: val = s.notaries.Load() } if val != nil { return val.(*roleData) } return nil } // GetLastDesignatedHash returns last designated hash of a given role. func (s *Designate) GetLastDesignatedHash(d dao.DAO, r Role) (util.Uint160, error) { if !s.isValidRole(r) { return util.Uint160{}, ErrInvalidRole } if !s.rolesChanged() { if val := s.getCachedRoleData(r); val != nil { return val.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 s.hashFromNodes(r, 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 !s.rolesChanged() { if val := s.getCachedRoleData(r); val != nil && val.height <= index { return val.nodes.Copy(), val.height, nil } } kvs, err := d.GetStorageItemsWithPrefix(s.ID, []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 stackitem.Null{} } // 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.ID, 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.ID, 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)) }