package smart_contract /* NeoFS Smart Contract for NEO3.0. Utility methods, executed once in deploy stage: - Init - InitConfig User related methods: - Deposit - Withdraw - Bind - Unbind Inner ring list related methods: - InnerRingList - InnerRingCandidates - IsInnerRing - InnerRingCandidateAdd - InnerRingCandidateRemove - InnerRingUpdate Config methods: - Config - ListConfig - SetConfig Other utility methods: - Version - Cheque */ import ( "github.com/nspcc-dev/neo-go/pkg/interop" "github.com/nspcc-dev/neo-go/pkg/interop/binary" "github.com/nspcc-dev/neo-go/pkg/interop/blockchain" "github.com/nspcc-dev/neo-go/pkg/interop/contract" "github.com/nspcc-dev/neo-go/pkg/interop/crypto" "github.com/nspcc-dev/neo-go/pkg/interop/iterator" "github.com/nspcc-dev/neo-go/pkg/interop/runtime" "github.com/nspcc-dev/neo-go/pkg/interop/storage" "github.com/nspcc-dev/neo-go/pkg/interop/util" ) type ( ballot struct { id []byte // id of the voting decision n [][]byte // already voted inner ring nodes block int // block with the last vote } node struct { pub []byte } cheque struct { id []byte } record struct { key []byte val []byte } ) const ( // native gas token script hash tokenHash = "\x20\x2a\x2d\xd3\xf6\xa6\xe8\xf4\xd3\xb5\xaf\x26\xa7\xfe\xde\xba\x4b\x80\xdf\xb5" defaultCandidateFee = 100 * 1_0000_0000 // 100 Fixed8 Gas candidateFeeConfigKey = "InnerRingCandidateFee" version = 3 innerRingKey = "innerring" voteKey = "ballots" candidatesKey = "candidates" cashedChequesKey = "cheques" blockDiff = 20 // change base on performance evaluation publicKeySize = 33 minInnerRingSize = 3 maxBalanceAmount = 9000 // Max integer of Fixed12 in JSON bound (2**53-1) // hardcoded value to ignore deposit notification in onReceive ignoreDepositNotification = "\x57\x0b" ) var ( configPrefix = []byte("config") ctx storage.Context ) func init() { // The trigger determines whether this smart-contract is being // run in 'verification' or 'application' mode. if runtime.GetTrigger() != runtime.Application { panic("contract has not been called in application node") } ctx = storage.GetContext() } // Init set up initial inner ring node keys. func Init(args [][]byte) bool { if storage.Get(ctx, innerRingKey) != nil { panic("neofs: contract already deployed") } var irList []node if len(args) < 3 { panic("neofs: at least three inner ring keys must be provided") } for i := 0; i < len(args); i++ { pub := args[i] if len(pub) != publicKeySize { panic("neofs: incorrect public key length") } irList = append(irList, node{pub: pub}) } // initialize all storage slices setSerialized(ctx, innerRingKey, irList) setSerialized(ctx, voteKey, []ballot{}) setSerialized(ctx, candidatesKey, []node{}) setSerialized(ctx, cashedChequesKey, []cheque{}) runtime.Log("neofs: contract initialized") return true } // InnerRingList returns array of inner ring node keys. func InnerRingList() []node { return getInnerRingNodes(ctx, innerRingKey) } // InnerRingCandidates returns array of inner ring candidate node keys. func InnerRingCandidates() []node { return getInnerRingNodes(ctx, candidatesKey) } // InnerRingCandidateRemove removes key from the list of inner ring candidates. func InnerRingCandidateRemove(key []byte) bool { if !runtime.CheckWitness(key) { panic("irCandidateRemove: you should be the owner of the public key") } nodes := []node{} // it is explicit declaration of empty slice, not nil candidates := getInnerRingNodes(ctx, candidatesKey) for i := range candidates { c := candidates[i] if !bytesEqual(c.pub, key) { nodes = append(nodes, c) } else { runtime.Log("irCandidateRemove: candidate has been removed") } } setSerialized(ctx, candidatesKey, nodes) return true } // InnerRingCandidateAdd adds key to the list of inner ring candidates. func InnerRingCandidateAdd(key []byte) bool { if !runtime.CheckWitness(key) { panic("irCandidateAdd: you should be the owner of the public key") } c := node{pub: key} candidates := getInnerRingNodes(ctx, candidatesKey) list, ok := addNode(candidates, c) if !ok { panic("irCandidateAdd: candidate already in the list") } from := contract.CreateStandardAccount(key) to := runtime.GetExecutingScriptHash() fee := getConfig(ctx, candidateFeeConfigKey).(int) transferred := contract.Call([]byte(tokenHash), "transfer", from, to, fee, []byte(ignoreDepositNotification)).(bool) if !transferred { panic("irCandidateAdd: failed to transfer funds, aborting") } runtime.Log("irCandidateAdd: candidate has been added") setSerialized(ctx, candidatesKey, list) return true } // OnPayment is a callback for NEP-17 compatible native GAS contract. func OnPayment(from interop.Hash160, amount int, data interface{}) { rcv := data.(interop.Hash160) if bytesEqual(rcv, []byte(ignoreDepositNotification)) { return } caller := runtime.GetCallingScriptHash() if !bytesEqual(caller, []byte(tokenHash)) { panic("onPayment: only GAS can be accepted for deposit") } switch len(rcv) { case 20: case 0: rcv = from default: panic("onPayment: invalid data argument, expected Hash160") } runtime.Log("onPayment: funds have been transferred") tx := runtime.GetScriptContainer() runtime.Notify("Deposit", from, amount, rcv, tx.Hash) } // Deposit gas assets to this script-hash address in NeoFS balance contract. func Deposit(from interop.Hash160, amount int, rcv interop.Hash160) bool { if !runtime.CheckWitness(from) { panic("deposit: you should be the owner of the wallet") } if amount > maxBalanceAmount { panic("deposit: out of max amount limit") } if amount <= 0 { return false } amount = amount * 100000000 to := runtime.GetExecutingScriptHash() transferred := contract.Call([]byte(tokenHash), "transfer", from, to, amount, rcv).(bool) if !transferred { panic("deposit: failed to transfer funds, aborting") } return true } // Withdraw initialize gas asset withdraw from NeoFS balance. func Withdraw(user []byte, amount int) bool { if !runtime.CheckWitness(user) { panic("withdraw: you should be the owner of the wallet") } if amount < 0 { panic("withdraw: non positive amount number") } if amount > maxBalanceAmount { panic("withdraw: out of max amount limit") } amount = amount * 100000000 tx := runtime.GetScriptContainer() runtime.Notify("Withdraw", user, amount, tx.Hash) return true } // Cheque sends gas assets back to the user if they were successfully // locked in NeoFS balance contract. func Cheque(id, user []byte, amount int, lockAcc []byte) bool { irList := getInnerRingNodes(ctx, innerRingKey) threshold := len(irList)/3*2 + 1 cashedCheques := getCashedCheques(ctx) hashID := crypto.SHA256(id) irKey := innerRingInvoker(irList) if len(irKey) == 0 { panic("cheque: invoked by non inner ring node") } c := cheque{id: id} list, ok := addCheque(cashedCheques, c) if !ok { panic("cheque: non unique id") } n := vote(ctx, hashID, irKey) if n >= threshold { removeVotes(ctx, hashID) from := runtime.GetExecutingScriptHash() transferred := contract.Call([]byte(tokenHash), "transfer", from, user, amount, nil).(bool) if !transferred { panic("cheque: failed to transfer funds, aborting") } runtime.Log("cheque: funds have been transferred") setSerialized(ctx, cashedChequesKey, list) runtime.Notify("Cheque", id, user, amount, lockAcc) } return true } // Bind public key with user's account to use it in NeoFS requests. func Bind(user []byte, keys [][]byte) bool { if !runtime.CheckWitness(user) { panic("binding: you should be the owner of the wallet") } for i := 0; i < len(keys); i++ { pubKey := keys[i] if len(pubKey) != publicKeySize { panic("binding: incorrect public key size") } } runtime.Notify("Bind", user, keys) return true } // Unbind public key from user's account func Unbind(user []byte, keys [][]byte) bool { if !runtime.CheckWitness(user) { panic("unbinding: you should be the owner of the wallet") } for i := 0; i < len(keys); i++ { pubKey := keys[i] if len(pubKey) != publicKeySize { panic("unbinding: incorrect public key size") } } runtime.Notify("Unbind", user, keys) return true } // InnerRingUpdate updates list of inner ring nodes with provided list of // public keys. func InnerRingUpdate(chequeID []byte, args [][]byte) bool { if len(args) < minInnerRingSize { panic("irUpdate: bad arguments") } irList := getInnerRingNodes(ctx, innerRingKey) threshold := len(irList)/3*2 + 1 irKey := innerRingInvoker(irList) if len(irKey) == 0 { panic("innerRingUpdate: invoked by non inner ring node") } c := cheque{id: chequeID} cashedCheques := getCashedCheques(ctx) chequesList, ok := addCheque(cashedCheques, c) if !ok { panic("irUpdate: non unique chequeID") } oldNodes := 0 candidates := getInnerRingNodes(ctx, candidatesKey) newIR := []node{} loop: for i := 0; i < len(args); i++ { key := args[i] if len(key) != publicKeySize { panic("irUpdate: invalid public key in inner ring list") } // find key in actual inner ring list for j := 0; j < len(irList); j++ { n := irList[j] if bytesEqual(n.pub, key) { newIR = append(newIR, n) oldNodes++ continue loop } } // find key in candidates list candidates, newIR, ok = rmNodeByKey(candidates, newIR, key) if !ok { panic("irUpdate: unknown public key in inner ring list") } } if oldNodes < len(newIR)*2/3+1 { panic("irUpdate: inner ring change rate must not be more than 1/3 ") } hashID := crypto.SHA256(chequeID) n := vote(ctx, hashID, irKey) if n >= threshold { removeVotes(ctx, hashID) setSerialized(ctx, candidatesKey, candidates) setSerialized(ctx, innerRingKey, newIR) setSerialized(ctx, cashedChequesKey, chequesList) runtime.Notify("InnerRingUpdate", c.id, newIR) runtime.Log("irUpdate: inner ring list has been updated") } return true } // IsInnerRing returns 'true' if key is inside of inner ring list. func IsInnerRing(key []byte) bool { if len(key) != publicKeySize { panic("isInnerRing: incorrect public key") } irList := getInnerRingNodes(ctx, innerRingKey) for i := range irList { node := irList[i] if bytesEqual(node.pub, key) { return true } } return false } // Config returns value of NeoFS configuration with provided key. func Config(key []byte) interface{} { return getConfig(ctx, key) } // SetConfig key-value pair as a NeoFS runtime configuration value. func SetConfig(id, key, val []byte) bool { // check if it is inner ring invocation irList := getInnerRingNodes(ctx, innerRingKey) threshold := len(irList)/3*2 + 1 irKey := innerRingInvoker(irList) if len(irKey) == 0 { panic("setConfig: invoked by non inner ring node") } // check unique id of the operation c := cheque{id: id} cashedCheques := getCashedCheques(ctx) chequesList, ok := addCheque(cashedCheques, c) if !ok { panic("setConfig: non unique id") } // vote for new configuration value hashID := crypto.SHA256(id) n := vote(ctx, hashID, irKey) if n >= threshold { removeVotes(ctx, hashID) setConfig(ctx, key, val) setSerialized(ctx, cashedChequesKey, chequesList) runtime.Notify("SetConfig", id, key, val) runtime.Log("setConfig: configuration has been updated") } return true } // ListConfig returns array of all key-value pairs of NeoFS configuration. func ListConfig() []record { var config []record it := storage.Find(ctx, configPrefix) for iterator.Next(it) { key := iterator.Key(it).([]byte) val := iterator.Value(it).([]byte) r := record{key: key[len(configPrefix):], val: val} config = append(config, r) } return config } // InitConfig set up initial NeoFS key-value configuration. func InitConfig(args [][]byte) bool { if getConfig(ctx, candidateFeeConfigKey) != nil { panic("neofs: configuration already installed") } ln := len(args) if ln%2 != 0 { panic("initConfig: bad arguments") } setConfig(ctx, candidateFeeConfigKey, defaultCandidateFee) for i := 0; i < ln/2; i++ { key := args[i*2] val := args[i*2+1] setConfig(ctx, key, val) } runtime.Log("neofs: config has been installed") return true } // Version of contract. func Version() int { return version } // innerRingInvoker returns public key of inner ring node that invoked contract. func innerRingInvoker(ir []node) []byte { for i := 0; i < len(ir); i++ { node := ir[i] if runtime.CheckWitness(node.pub) { return node.pub } } return nil } // vote adds ballot for the decision with specific 'id' and returns amount // on unique voters for that decision. func vote(ctx storage.Context, id, from []byte) int { var ( newCandidates = []ballot{} // it is explicit declaration of empty slice, not nil candidates = getBallots(ctx) found = -1 blockHeight = blockchain.GetHeight() ) for i := 0; i < len(candidates); i++ { cnd := candidates[i] if bytesEqual(cnd.id, id) { voters := cnd.n for j := range voters { if bytesEqual(voters[j], from) { return len(voters) } } voters = append(voters, from) cnd = ballot{id: id, n: voters, block: blockHeight} found = len(voters) } // do not add old ballots, they are invalid if blockHeight-cnd.block <= blockDiff { newCandidates = append(newCandidates, cnd) } } if found < 0 { found = 1 voters := [][]byte{from} newCandidates = append(newCandidates, ballot{ id: id, n: voters, block: blockHeight}) } setSerialized(ctx, voteKey, newCandidates) return found } // removeVotes clears ballots of the decision that has been accepted by // inner ring nodes. func removeVotes(ctx storage.Context, id []byte) { var ( newCandidates = []ballot{} // it is explicit declaration of empty slice, not nil candidates = getBallots(ctx) ) for i := 0; i < len(candidates); i++ { cnd := candidates[i] if !bytesEqual(cnd.id, id) { newCandidates = append(newCandidates, cnd) } } setSerialized(ctx, voteKey, newCandidates) } // setSerialized serializes data and puts it into contract storage. func setSerialized(ctx storage.Context, key interface{}, value interface{}) { data := binary.Serialize(value) storage.Put(ctx, key, data) } // getInnerRingNodes returns deserialized slice of inner ring nodes from storage. func getInnerRingNodes(ctx storage.Context, key string) []node { data := storage.Get(ctx, key) if data != nil { return binary.Deserialize(data.([]byte)).([]node) } return []node{} } // getInnerRingNodes returns deserialized slice of used cheques. func getCashedCheques(ctx storage.Context) []cheque { data := storage.Get(ctx, cashedChequesKey) if data != nil { return binary.Deserialize(data.([]byte)).([]cheque) } return []cheque{} } // getInnerRingNodes returns deserialized slice of vote ballots. func getBallots(ctx storage.Context) []ballot { data := storage.Get(ctx, voteKey) if data != nil { return binary.Deserialize(data.([]byte)).([]ballot) } return []ballot{} } // getConfig returns installed neofs configuration value or nil if it is not set. func getConfig(ctx storage.Context, key interface{}) interface{} { postfix := key.([]byte) storageKey := append(configPrefix, postfix...) return storage.Get(ctx, storageKey) } // setConfig sets neofs configuration value in the contract storage. func setConfig(ctx storage.Context, key, val interface{}) { postfix := key.([]byte) storageKey := append(configPrefix, postfix...) storage.Put(ctx, storageKey, val) } // addCheque returns slice of cheques with appended cheque 'c' and bool flag // that set to false if cheque 'c' is already presented in the slice 'lst'. func addCheque(lst []cheque, c cheque) ([]cheque, bool) { for i := 0; i < len(lst); i++ { if bytesEqual(c.id, lst[i].id) { return nil, false } } lst = append(lst, c) return lst, true } // addNode returns slice of nodes with appended node 'n' and bool flag // that set to false if node 'n' is already presented in the slice 'lst'. func addNode(lst []node, n node) ([]node, bool) { for i := 0; i < len(lst); i++ { if bytesEqual(n.pub, lst[i].pub) { return nil, false } } lst = append(lst, n) return lst, true } // rmNodeByKey returns slice of nodes without node with key 'k', // slices of nodes 'add' with node with key 'k' and bool flag, // that set to false if node with a key 'k' does not exists in the slice 'lst'. func rmNodeByKey(lst, add []node, k []byte) ([]node, []node, bool) { var ( flag bool newLst = []node{} // it is explicit declaration of empty slice, not nil ) for i := 0; i < len(lst); i++ { if bytesEqual(k, lst[i].pub) { add = append(add, lst[i]) flag = true } else { newLst = append(newLst, lst[i]) } } return newLst, add, flag } // bytesEqual compares two slice of bytes by wrapping them into strings, // which is necessary with new util.Equal interop behaviour, see neo-go#1176. func bytesEqual(a []byte, b []byte) bool { return util.Equals(string(a), string(b)) }