package native import ( "encoding/json" "errors" "fmt" "math" "math/big" "unicode/utf8" "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/contract" "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/core/storage" "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/callflag" "github.com/nspcc-dev/neo-go/pkg/smartcontract/manifest" "github.com/nspcc-dev/neo-go/pkg/smartcontract/nef" "github.com/nspcc-dev/neo-go/pkg/util" "github.com/nspcc-dev/neo-go/pkg/util/bitfield" "github.com/nspcc-dev/neo-go/pkg/vm" "github.com/nspcc-dev/neo-go/pkg/vm/stackitem" ) // Management is a contract-managing native contract. type Management struct { interop.ContractMD NEO *NEO Policy *Policy } type ManagementCache struct { contracts map[util.Uint160]*state.Contract // nep11 is a map of NEP11-compliant contracts which is updated with every PostPersist. nep11 map[util.Uint160]struct{} // nep17 is a map of NEP-17-compliant contracts which is updated with every PostPersist. nep17 map[util.Uint160]struct{} } const ( ManagementContractID = -1 prefixContract = 8 defaultMinimumDeploymentFee = 10_00000000 contractDeployNotificationName = "Deploy" contractUpdateNotificationName = "Update" contractDestroyNotificationName = "Destroy" ) var ( errGasLimitExceeded = errors.New("gas limit exceeded") keyNextAvailableID = []byte{15} keyMinimumDeploymentFee = []byte{20} ) var ( _ interop.Contract = (*Management)(nil) _ dao.NativeContractCache = (*ManagementCache)(nil) ) // Copy implements NativeContractCache interface. func (c *ManagementCache) Copy() dao.NativeContractCache { cp := &ManagementCache{ contracts: make(map[util.Uint160]*state.Contract), nep11: make(map[util.Uint160]struct{}), nep17: make(map[util.Uint160]struct{}), } // Copy the whole set of contracts is too expensive. We will create a separate map // holding the same set of pointers to contracts, and in case if some contract is // supposed to be changed, Management will create the copy in-place. for hash, ctr := range c.contracts { cp.contracts[hash] = ctr } for hash := range c.nep17 { cp.nep17[hash] = struct{}{} } for hash := range c.nep11 { cp.nep11[hash] = struct{}{} } return cp } // MakeContractKey creates a key from the account script hash. func MakeContractKey(h util.Uint160) []byte { return makeUint160Key(prefixContract, h) } // newManagement creates a new Management native contract. func newManagement() *Management { var m = &Management{ ContractMD: *interop.NewContractMD(nativenames.Management, ManagementContractID), } defer m.UpdateHash() desc := newDescriptor("getContract", smartcontract.ArrayType, manifest.NewParameter("hash", smartcontract.Hash160Type)) md := newMethodAndPrice(m.getContract, 1<<15, callflag.ReadStates) m.AddMethod(md, desc) desc = newDescriptor("deploy", smartcontract.ArrayType, manifest.NewParameter("nefFile", smartcontract.ByteArrayType), manifest.NewParameter("manifest", smartcontract.ByteArrayType)) md = newMethodAndPrice(m.deploy, 0, callflag.All) m.AddMethod(md, desc) desc = newDescriptor("deploy", smartcontract.ArrayType, manifest.NewParameter("nefFile", smartcontract.ByteArrayType), manifest.NewParameter("manifest", smartcontract.ByteArrayType), manifest.NewParameter("data", smartcontract.AnyType)) md = newMethodAndPrice(m.deployWithData, 0, callflag.All) m.AddMethod(md, desc) desc = newDescriptor("update", smartcontract.VoidType, manifest.NewParameter("nefFile", smartcontract.ByteArrayType), manifest.NewParameter("manifest", smartcontract.ByteArrayType)) md = newMethodAndPrice(m.update, 0, callflag.All) m.AddMethod(md, desc) desc = newDescriptor("update", smartcontract.VoidType, manifest.NewParameter("nefFile", smartcontract.ByteArrayType), manifest.NewParameter("manifest", smartcontract.ByteArrayType), manifest.NewParameter("data", smartcontract.AnyType)) md = newMethodAndPrice(m.updateWithData, 0, callflag.All) m.AddMethod(md, desc) desc = newDescriptor("destroy", smartcontract.VoidType) md = newMethodAndPrice(m.destroy, 1<<15, callflag.States|callflag.AllowNotify) m.AddMethod(md, desc) desc = newDescriptor("getMinimumDeploymentFee", smartcontract.IntegerType) md = newMethodAndPrice(m.getMinimumDeploymentFee, 1<<15, callflag.ReadStates) m.AddMethod(md, desc) desc = newDescriptor("setMinimumDeploymentFee", smartcontract.VoidType, manifest.NewParameter("value", smartcontract.IntegerType)) md = newMethodAndPrice(m.setMinimumDeploymentFee, 1<<15, callflag.States) m.AddMethod(md, desc) desc = newDescriptor("hasMethod", smartcontract.IntegerType, manifest.NewParameter("hash", smartcontract.Hash160Type), manifest.NewParameter("method", smartcontract.StringType), manifest.NewParameter("pcount", smartcontract.IntegerType)) md = newMethodAndPrice(m.hasMethod, 1<<15, callflag.ReadStates) m.AddMethod(md, desc) hashParam := manifest.NewParameter("Hash", smartcontract.Hash160Type) m.AddEvent(contractDeployNotificationName, hashParam) m.AddEvent(contractUpdateNotificationName, hashParam) m.AddEvent(contractDestroyNotificationName, hashParam) return m } func toHash160(si stackitem.Item) util.Uint160 { hashBytes, err := si.TryBytes() if err != nil { panic(err) } hash, err := util.Uint160DecodeBytesBE(hashBytes) if err != nil { panic(err) } return hash } // getContract is an implementation of public getContract method, it's run under // VM protections, so it's OK for it to panic instead of returning errors. func (m *Management) getContract(ic *interop.Context, args []stackitem.Item) stackitem.Item { hash := toHash160(args[0]) ctr, err := m.GetContract(ic.DAO, hash) if err != nil { if err == storage.ErrKeyNotFound { return stackitem.Null{} } panic(err) } return contractToStack(ctr) } // GetContract returns a contract with the given hash from the given DAO. func (m *Management) GetContract(d *dao.Simple, hash util.Uint160) (*state.Contract, error) { cache := d.GetROCache(m.ID).(*ManagementCache) cs, ok := cache.contracts[hash] if !ok { return nil, storage.ErrKeyNotFound } return cs, nil } func getLimitedSlice(arg stackitem.Item, max int) ([]byte, error) { _, isNull := arg.(stackitem.Null) if isNull { return nil, nil } b, err := arg.TryBytes() if err != nil { return nil, err } l := len(b) if l == 0 { return nil, errors.New("empty") } else if l > max { return nil, fmt.Errorf("len is %d (max %d)", l, max) } return b, nil } // getNefAndManifestFromItems converts input arguments into NEF and manifest // adding an appropriate deployment GAS price and sanitizing inputs. func (m *Management) getNefAndManifestFromItems(ic *interop.Context, args []stackitem.Item, isDeploy bool) (*nef.File, *manifest.Manifest, error) { nefBytes, err := getLimitedSlice(args[0], math.MaxInt32) // Upper limits are checked during NEF deserialization. if err != nil { return nil, nil, fmt.Errorf("invalid NEF file: %w", err) } manifestBytes, err := getLimitedSlice(args[1], manifest.MaxManifestSize) if err != nil { return nil, nil, fmt.Errorf("invalid manifest: %w", err) } gas := ic.BaseStorageFee() * int64(len(nefBytes)+len(manifestBytes)) if isDeploy { fee := m.minimumDeploymentFee(ic.DAO) if fee > gas { gas = fee } } if !ic.VM.AddGas(gas) { return nil, nil, errGasLimitExceeded } var resManifest *manifest.Manifest var resNef *nef.File if nefBytes != nil { nf, err := nef.FileFromBytes(nefBytes) if err != nil { return nil, nil, fmt.Errorf("invalid NEF file: %w", err) } resNef = &nf } if manifestBytes != nil { if !utf8.Valid(manifestBytes) { return nil, nil, errors.New("manifest is not UTF-8 compliant") } resManifest = new(manifest.Manifest) err := json.Unmarshal(manifestBytes, resManifest) if err != nil { return nil, nil, fmt.Errorf("invalid manifest: %w", err) } } return resNef, resManifest, nil } // deploy is an implementation of public 2-argument deploy method. func (m *Management) deploy(ic *interop.Context, args []stackitem.Item) stackitem.Item { return m.deployWithData(ic, append(args, stackitem.Null{})) } // deployWithData is an implementation of public 3-argument deploy method. // It's run under VM protections, so it's OK for it to panic instead of returning errors. func (m *Management) deployWithData(ic *interop.Context, args []stackitem.Item) stackitem.Item { neff, manif, err := m.getNefAndManifestFromItems(ic, args, true) if err != nil { panic(err) } if neff == nil { panic(errors.New("no valid NEF provided")) } if manif == nil { panic(errors.New("no valid manifest provided")) } if ic.Tx == nil { panic(errors.New("no transaction provided")) } newcontract, err := m.Deploy(ic.DAO, ic.Tx.Sender(), neff, manif) if err != nil { panic(err) } m.callDeploy(ic, newcontract, args[2], false) m.emitNotification(ic, contractDeployNotificationName, newcontract.Hash) return contractToStack(newcontract) } func markUpdated(d *dao.Simple, hash util.Uint160, cs *state.Contract) { cache := d.GetRWCache(ManagementContractID).(*ManagementCache) delete(cache.nep11, hash) delete(cache.nep17, hash) if cs == nil { delete(cache.contracts, hash) return } updateContractCache(cache, cs) } // Deploy creates a contract's hash/ID and saves a new contract into the given DAO. // It doesn't run _deploy method and doesn't emit notification. func (m *Management) Deploy(d *dao.Simple, sender util.Uint160, neff *nef.File, manif *manifest.Manifest) (*state.Contract, error) { h := state.CreateContractHash(sender, neff.Checksum, manif.Name) if m.Policy.IsBlocked(d, h) { return nil, fmt.Errorf("the contract %s has been blocked", h.StringLE()) } _, err := m.GetContract(d, h) if err == nil { return nil, errors.New("contract already exists") } id, err := m.getNextContractID(d) if err != nil { return nil, err } err = manif.IsValid(h) if err != nil { return nil, fmt.Errorf("invalid manifest: %w", err) } err = checkScriptAndMethods(neff.Script, manif.ABI.Methods) if err != nil { return nil, err } newcontract := &state.Contract{ ContractBase: state.ContractBase{ ID: id, Hash: h, NEF: *neff, Manifest: *manif, }, } err = PutContractState(d, newcontract) if err != nil { return nil, err } return newcontract, nil } func (m *Management) update(ic *interop.Context, args []stackitem.Item) stackitem.Item { return m.updateWithData(ic, append(args, stackitem.Null{})) } // update is an implementation of public update method, it's run under // VM protections, so it's OK for it to panic instead of returning errors. func (m *Management) updateWithData(ic *interop.Context, args []stackitem.Item) stackitem.Item { neff, manif, err := m.getNefAndManifestFromItems(ic, args, false) if err != nil { panic(err) } if neff == nil && manif == nil { panic(errors.New("both NEF and manifest are nil")) } contract, err := m.Update(ic.DAO, ic.VM.GetCallingScriptHash(), neff, manif) if err != nil { panic(err) } m.callDeploy(ic, contract, args[2], true) m.emitNotification(ic, contractUpdateNotificationName, contract.Hash) return stackitem.Null{} } // Update updates contract's script and/or manifest in the given DAO. // It doesn't run _deploy method and doesn't emit notification. func (m *Management) Update(d *dao.Simple, hash util.Uint160, neff *nef.File, manif *manifest.Manifest) (*state.Contract, error) { var contract state.Contract oldcontract, err := m.GetContract(d, hash) if err != nil { return nil, errors.New("contract doesn't exist") } if oldcontract.UpdateCounter == math.MaxUint16 { return nil, errors.New("the contract reached the maximum number of updates") } contract = *oldcontract // Make a copy, don't ruin (potentially) cached contract. // if NEF was provided, update the contract script if neff != nil { contract.NEF = *neff } // if manifest was provided, update the contract manifest if manif != nil { if manif.Name != contract.Manifest.Name { return nil, errors.New("contract name can't be changed") } err = manif.IsValid(contract.Hash) if err != nil { return nil, fmt.Errorf("invalid manifest: %w", err) } contract.Manifest = *manif } err = checkScriptAndMethods(contract.NEF.Script, contract.Manifest.ABI.Methods) if err != nil { return nil, err } contract.UpdateCounter++ err = PutContractState(d, &contract) if err != nil { return nil, err } return &contract, nil } // destroy is an implementation of destroy update method, it's run under // VM protections, so it's OK for it to panic instead of returning errors. func (m *Management) destroy(ic *interop.Context, sis []stackitem.Item) stackitem.Item { hash := ic.VM.GetCallingScriptHash() err := m.Destroy(ic.DAO, hash) if err != nil { panic(err) } m.emitNotification(ic, contractDestroyNotificationName, hash) return stackitem.Null{} } // Destroy drops the given contract from DAO along with its storage. It doesn't emit notification. func (m *Management) Destroy(d *dao.Simple, hash util.Uint160) error { contract, err := m.GetContract(d, hash) if err != nil { return err } key := MakeContractKey(hash) d.DeleteStorageItem(m.ID, key) d.DeleteContractID(contract.ID) d.Seek(contract.ID, storage.SeekRange{}, func(k, _ []byte) bool { d.DeleteStorageItem(contract.ID, k) return true }) m.Policy.blockAccountInternal(d, hash) markUpdated(d, hash, nil) return nil } func (m *Management) getMinimumDeploymentFee(ic *interop.Context, args []stackitem.Item) stackitem.Item { return stackitem.NewBigInteger(big.NewInt(m.minimumDeploymentFee(ic.DAO))) } // minimumDeploymentFee returns the minimum required fee for contract deploy. func (m *Management) minimumDeploymentFee(dao *dao.Simple) int64 { return getIntWithKey(m.ID, dao, keyMinimumDeploymentFee) } func (m *Management) setMinimumDeploymentFee(ic *interop.Context, args []stackitem.Item) stackitem.Item { value := toBigInt(args[0]) if value.Sign() < 0 { panic("MinimumDeploymentFee cannot be negative") } if !m.NEO.checkCommittee(ic) { panic("invalid committee signature") } ic.DAO.PutStorageItem(m.ID, keyMinimumDeploymentFee, bigint.ToBytes(value)) return stackitem.Null{} } func (m *Management) callDeploy(ic *interop.Context, cs *state.Contract, data stackitem.Item, isUpdate bool) { md := cs.Manifest.ABI.GetMethod(manifest.MethodDeploy, 2) if md != nil { err := contract.CallFromNative(ic, m.Hash, cs, manifest.MethodDeploy, []stackitem.Item{data, stackitem.NewBool(isUpdate)}, false) if err != nil { panic(err) } } } func contractToStack(cs *state.Contract) stackitem.Item { si, err := cs.ToStackItem() if err != nil { panic(fmt.Errorf("contract to stack item: %w", err)) } return si } func (m *Management) hasMethod(ic *interop.Context, args []stackitem.Item) stackitem.Item { cHash := toHash160(args[0]) method, err := stackitem.ToString(args[1]) if err != nil { panic(err) } pcount := int(toInt64((args[2]))) cs, err := m.GetContract(ic.DAO, cHash) if err != nil { return stackitem.NewBool(false) } return stackitem.NewBool(cs.Manifest.ABI.GetMethod(method, pcount) != nil) } // Metadata implements the Contract interface. func (m *Management) Metadata() *interop.ContractMD { return &m.ContractMD } // updateContractCache saves the contract in the common and NEP-related caches. It's // an internal method that must be called with m.mtx lock taken. func updateContractCache(cache *ManagementCache, cs *state.Contract) { cache.contracts[cs.Hash] = cs if cs.Manifest.IsStandardSupported(manifest.NEP11StandardName) { cache.nep11[cs.Hash] = struct{}{} } if cs.Manifest.IsStandardSupported(manifest.NEP17StandardName) { cache.nep17[cs.Hash] = struct{}{} } } // OnPersist implements the Contract interface. func (m *Management) OnPersist(ic *interop.Context) error { var cache *ManagementCache for _, native := range ic.Natives { md := native.Metadata() history := md.UpdateHistory if len(history) == 0 || history[0] != ic.Block.Index { continue } cs := &state.Contract{ ContractBase: md.ContractBase, } if err := native.Initialize(ic); err != nil { return fmt.Errorf("initializing %s native contract: %w", md.Name, err) } err := putContractState(ic.DAO, cs, false) // Perform cache update manually. if err != nil { return err } if cache == nil { cache = ic.DAO.GetRWCache(m.ID).(*ManagementCache) } updateContractCache(cache, cs) } return nil } // InitializeCache initializes contract cache with the proper values from storage. // Cache initialization should be done apart from Initialize because Initialize is // called only when deploying native contracts. func (m *Management) InitializeCache(d *dao.Simple) error { cache := &ManagementCache{ contracts: make(map[util.Uint160]*state.Contract), nep11: make(map[util.Uint160]struct{}), nep17: make(map[util.Uint160]struct{}), } var initErr error d.Seek(m.ID, storage.SeekRange{Prefix: []byte{prefixContract}}, func(_, v []byte) bool { var cs = new(state.Contract) initErr = stackitem.DeserializeConvertible(v, cs) if initErr != nil { return false } updateContractCache(cache, cs) return true }) if initErr != nil { return initErr } d.SetCache(m.ID, cache) return nil } // PostPersist implements the Contract interface. func (m *Management) PostPersist(ic *interop.Context) error { return nil } // GetNEP11Contracts returns hashes of all deployed contracts that support NEP-11 standard. The list // is updated every PostPersist, so until PostPersist is called, the result for the previous block // is returned. func (m *Management) GetNEP11Contracts(d *dao.Simple) []util.Uint160 { cache := d.GetROCache(m.ID).(*ManagementCache) result := make([]util.Uint160, 0, len(cache.nep11)) for h := range cache.nep11 { result = append(result, h) } return result } // GetNEP17Contracts returns hashes of all deployed contracts that support NEP-17 standard. The list // is updated every PostPersist, so until PostPersist is called, the result for the previous block // is returned. func (m *Management) GetNEP17Contracts(d *dao.Simple) []util.Uint160 { cache := d.GetROCache(m.ID).(*ManagementCache) result := make([]util.Uint160, 0, len(cache.nep17)) for h := range cache.nep17 { result = append(result, h) } return result } // Initialize implements the Contract interface. func (m *Management) Initialize(ic *interop.Context) error { setIntWithKey(m.ID, ic.DAO, keyMinimumDeploymentFee, defaultMinimumDeploymentFee) setIntWithKey(m.ID, ic.DAO, keyNextAvailableID, 1) cache := &ManagementCache{ contracts: make(map[util.Uint160]*state.Contract), nep11: make(map[util.Uint160]struct{}), nep17: make(map[util.Uint160]struct{}), } ic.DAO.SetCache(m.ID, cache) return nil } // PutContractState saves given contract state into given DAO. func PutContractState(d *dao.Simple, cs *state.Contract) error { return putContractState(d, cs, true) } // putContractState is an internal PutContractState representation. func putContractState(d *dao.Simple, cs *state.Contract, updateCache bool) error { key := MakeContractKey(cs.Hash) if err := putConvertibleToDAO(ManagementContractID, d, key, cs); err != nil { return err } if updateCache { markUpdated(d, cs.Hash, cs) } if cs.UpdateCounter != 0 { // Update. return nil } d.PutContractID(cs.ID, cs.Hash) return nil } func (m *Management) getNextContractID(d *dao.Simple) (int32, error) { si := d.GetStorageItem(m.ID, keyNextAvailableID) if si == nil { return 0, errors.New("nextAvailableID is not initialized") } id := bigint.FromBytes(si) ret := int32(id.Int64()) id.Add(id, intOne) d.PutBigInt(m.ID, keyNextAvailableID, id) return ret, nil } func (m *Management) emitNotification(ic *interop.Context, name string, hash util.Uint160) { ic.AddNotification(m.Hash, name, stackitem.NewArray([]stackitem.Item{addrToStackItem(&hash)})) } func checkScriptAndMethods(script []byte, methods []manifest.Method) error { l := len(script) offsets := bitfield.New(l) for i := range methods { if methods[i].Offset >= l { continue } offsets.Set(methods[i].Offset) } return vm.IsScriptCorrect(script, offsets) }