mirror of
https://github.com/nspcc-dev/neo-go.git
synced 2024-11-23 03:38:35 +00:00
58ab3b5ad1
Not from DAO's items with storage.STNEP17Balances prefix, because changes are reflected there only after notifications processing. And this happens only after the transaction script is executed, but there might be cases when we need to get the balance that was updated earlier during the same transaction processing. Affects storage dumps.
331 lines
8.8 KiB
Go
331 lines
8.8 KiB
Go
package native
|
|
|
|
import (
|
|
"errors"
|
|
"fmt"
|
|
"math"
|
|
"math/big"
|
|
|
|
"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/interop/runtime"
|
|
"github.com/nspcc-dev/neo-go/pkg/core/state"
|
|
"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/util"
|
|
"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
|
|
)
|
|
|
|
// prefixAccount is the standard prefix used to store account data.
|
|
const prefixAccount = 20
|
|
|
|
// makeAccountKey creates a key from account script hash.
|
|
func makeAccountKey(h util.Uint160) []byte {
|
|
return makeUint160Key(prefixAccount, h)
|
|
}
|
|
|
|
// nep17TokenNative represents NEP-17 token contract.
|
|
type nep17TokenNative struct {
|
|
interop.ContractMD
|
|
symbol string
|
|
decimals int64
|
|
factor int64
|
|
incBalance func(*interop.Context, util.Uint160, *state.StorageItem, *big.Int) error
|
|
balFromBytes func(item *state.StorageItem) (*big.Int, error)
|
|
}
|
|
|
|
// totalSupplyKey is the key used to store totalSupply value.
|
|
var totalSupplyKey = []byte{11}
|
|
|
|
func (c *nep17TokenNative) Metadata() *interop.ContractMD {
|
|
return &c.ContractMD
|
|
}
|
|
|
|
func newNEP17Native(name string, id int32) *nep17TokenNative {
|
|
n := &nep17TokenNative{ContractMD: *interop.NewContractMD(name, id)}
|
|
n.Manifest.SupportedStandards = []string{manifest.NEP17StandardName}
|
|
|
|
desc := newDescriptor("symbol", smartcontract.StringType)
|
|
md := newMethodAndPrice(n.Symbol, 0, callflag.NoneFlag)
|
|
n.AddMethod(md, desc)
|
|
|
|
desc = newDescriptor("decimals", smartcontract.IntegerType)
|
|
md = newMethodAndPrice(n.Decimals, 0, callflag.NoneFlag)
|
|
n.AddMethod(md, desc)
|
|
|
|
desc = newDescriptor("totalSupply", smartcontract.IntegerType)
|
|
md = newMethodAndPrice(n.TotalSupply, 1<<15, callflag.ReadStates)
|
|
n.AddMethod(md, desc)
|
|
|
|
desc = newDescriptor("balanceOf", smartcontract.IntegerType,
|
|
manifest.NewParameter("account", smartcontract.Hash160Type))
|
|
md = newMethodAndPrice(n.balanceOf, 1<<15, callflag.ReadStates)
|
|
n.AddMethod(md, desc)
|
|
|
|
transferParams := []manifest.Parameter{
|
|
manifest.NewParameter("from", smartcontract.Hash160Type),
|
|
manifest.NewParameter("to", smartcontract.Hash160Type),
|
|
manifest.NewParameter("amount", smartcontract.IntegerType),
|
|
}
|
|
desc = newDescriptor("transfer", smartcontract.BoolType,
|
|
append(transferParams, manifest.NewParameter("data", smartcontract.AnyType))...,
|
|
)
|
|
md = newMethodAndPrice(n.Transfer, 1<<17, callflag.States|callflag.AllowCall|callflag.AllowNotify)
|
|
md.StorageFee = 50
|
|
n.AddMethod(md, desc)
|
|
|
|
n.AddEvent("Transfer", transferParams...)
|
|
|
|
return n
|
|
}
|
|
|
|
func (c *nep17TokenNative) Initialize(_ *interop.Context) error {
|
|
return nil
|
|
}
|
|
|
|
func (c *nep17TokenNative) Symbol(_ *interop.Context, _ []stackitem.Item) stackitem.Item {
|
|
return stackitem.NewByteArray([]byte(c.symbol))
|
|
}
|
|
|
|
func (c *nep17TokenNative) Decimals(_ *interop.Context, _ []stackitem.Item) stackitem.Item {
|
|
return stackitem.NewBigInteger(big.NewInt(c.decimals))
|
|
}
|
|
|
|
func (c *nep17TokenNative) TotalSupply(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
|
|
return stackitem.NewBigInteger(c.getTotalSupply(ic.DAO))
|
|
}
|
|
|
|
func (c *nep17TokenNative) getTotalSupply(d dao.DAO) *big.Int {
|
|
si := d.GetStorageItem(c.ID, totalSupplyKey)
|
|
if si == nil {
|
|
return big.NewInt(0)
|
|
}
|
|
return bigint.FromBytes(si)
|
|
}
|
|
|
|
func (c *nep17TokenNative) saveTotalSupply(d dao.DAO, supply *big.Int) error {
|
|
return d.PutStorageItem(c.ID, totalSupplyKey, bigint.ToBytes(supply))
|
|
}
|
|
|
|
func (c *nep17TokenNative) Transfer(ic *interop.Context, args []stackitem.Item) stackitem.Item {
|
|
from := toUint160(args[0])
|
|
to := toUint160(args[1])
|
|
amount := toBigInt(args[2])
|
|
err := c.TransferInternal(ic, from, to, amount, args[3])
|
|
return stackitem.NewBool(err == nil)
|
|
}
|
|
|
|
func addrToStackItem(u *util.Uint160) stackitem.Item {
|
|
if u == nil {
|
|
return stackitem.Null{}
|
|
}
|
|
return stackitem.NewByteArray(u.BytesBE())
|
|
}
|
|
|
|
func (c *nep17TokenNative) postTransfer(ic *interop.Context, from, to *util.Uint160, amount *big.Int,
|
|
data stackitem.Item, callOnPayment bool) {
|
|
c.emitTransfer(ic, from, to, amount)
|
|
if to == nil || !callOnPayment {
|
|
return
|
|
}
|
|
cs, err := ic.GetContract(*to)
|
|
if err != nil {
|
|
return
|
|
}
|
|
|
|
fromArg := stackitem.Item(stackitem.Null{})
|
|
if from != nil {
|
|
fromArg = stackitem.NewByteArray((*from).BytesBE())
|
|
}
|
|
args := []stackitem.Item{
|
|
fromArg,
|
|
stackitem.NewBigInteger(amount),
|
|
data,
|
|
}
|
|
if err := contract.CallFromNative(ic, c.Hash, cs, manifest.MethodOnNEP17Payment, args, false); err != nil {
|
|
panic(err)
|
|
}
|
|
}
|
|
|
|
func (c *nep17TokenNative) emitTransfer(ic *interop.Context, from, to *util.Uint160, amount *big.Int) {
|
|
ne := state.NotificationEvent{
|
|
ScriptHash: c.Hash,
|
|
Name: "Transfer",
|
|
Item: stackitem.NewArray([]stackitem.Item{
|
|
addrToStackItem(from),
|
|
addrToStackItem(to),
|
|
stackitem.NewBigInteger(amount),
|
|
}),
|
|
}
|
|
ic.Notifications = append(ic.Notifications, ne)
|
|
}
|
|
|
|
func (c *nep17TokenNative) updateAccBalance(ic *interop.Context, acc util.Uint160, amount *big.Int) error {
|
|
key := makeAccountKey(acc)
|
|
si := ic.DAO.GetStorageItem(c.ID, key)
|
|
if si == nil {
|
|
if amount.Sign() <= 0 {
|
|
return errors.New("insufficient funds")
|
|
}
|
|
si = state.StorageItem{}
|
|
}
|
|
|
|
err := c.incBalance(ic, acc, &si, amount)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
if si == nil {
|
|
err = ic.DAO.DeleteStorageItem(c.ID, key)
|
|
} else {
|
|
err = ic.DAO.PutStorageItem(c.ID, key, si)
|
|
}
|
|
return err
|
|
}
|
|
|
|
// TransferInternal transfers NEO between accounts.
|
|
func (c *nep17TokenNative) TransferInternal(ic *interop.Context, from, to util.Uint160, amount *big.Int, data stackitem.Item) error {
|
|
if amount.Sign() == -1 {
|
|
return errors.New("negative amount")
|
|
}
|
|
|
|
caller := ic.VM.GetCallingScriptHash()
|
|
if caller.Equals(util.Uint160{}) || !from.Equals(caller) {
|
|
ok, err := runtime.CheckHashedWitness(ic, from)
|
|
if err != nil {
|
|
return err
|
|
} else if !ok {
|
|
return errors.New("invalid signature")
|
|
}
|
|
}
|
|
isEmpty := from.Equals(to) || amount.Sign() == 0
|
|
inc := amount
|
|
if isEmpty {
|
|
inc = big.NewInt(0)
|
|
} else {
|
|
inc = new(big.Int).Neg(inc)
|
|
}
|
|
if err := c.updateAccBalance(ic, from, inc); err != nil {
|
|
return err
|
|
}
|
|
|
|
if !isEmpty {
|
|
if err := c.updateAccBalance(ic, to, amount); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
c.postTransfer(ic, &from, &to, amount, data, true)
|
|
return nil
|
|
}
|
|
|
|
func (c *nep17TokenNative) balanceOf(ic *interop.Context, args []stackitem.Item) stackitem.Item {
|
|
h := toUint160(args[0])
|
|
key := makeAccountKey(h)
|
|
si := ic.DAO.GetStorageItem(c.ID, key)
|
|
if si == nil {
|
|
return stackitem.NewBigInteger(big.NewInt(0))
|
|
}
|
|
balance, err := c.balFromBytes(&si)
|
|
if err != nil {
|
|
panic(fmt.Errorf("can not deserialize balance state: %w", err))
|
|
}
|
|
return stackitem.NewBigInteger(balance)
|
|
}
|
|
|
|
func (c *nep17TokenNative) mint(ic *interop.Context, h util.Uint160, amount *big.Int, callOnPayment bool) {
|
|
if amount.Sign() == 0 {
|
|
return
|
|
}
|
|
c.addTokens(ic, h, amount)
|
|
c.postTransfer(ic, nil, &h, amount, stackitem.Null{}, callOnPayment)
|
|
}
|
|
|
|
func (c *nep17TokenNative) burn(ic *interop.Context, h util.Uint160, amount *big.Int) {
|
|
if amount.Sign() == 0 {
|
|
return
|
|
}
|
|
c.addTokens(ic, h, new(big.Int).Neg(amount))
|
|
c.postTransfer(ic, &h, nil, amount, stackitem.Null{}, false)
|
|
}
|
|
|
|
func (c *nep17TokenNative) addTokens(ic *interop.Context, h util.Uint160, amount *big.Int) {
|
|
if amount.Sign() == 0 {
|
|
return
|
|
}
|
|
|
|
key := makeAccountKey(h)
|
|
si := ic.DAO.GetStorageItem(c.ID, key)
|
|
if si == nil {
|
|
si = state.StorageItem{}
|
|
}
|
|
if err := c.incBalance(ic, h, &si, amount); err != nil {
|
|
panic(err)
|
|
}
|
|
var err error
|
|
if si == nil {
|
|
err = ic.DAO.DeleteStorageItem(c.ID, key)
|
|
} else {
|
|
err = ic.DAO.PutStorageItem(c.ID, key, si)
|
|
}
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
|
|
supply := c.getTotalSupply(ic.DAO)
|
|
supply.Add(supply, amount)
|
|
err = c.saveTotalSupply(ic.DAO, supply)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
}
|
|
|
|
func newDescriptor(name string, ret smartcontract.ParamType, ps ...manifest.Parameter) *manifest.Method {
|
|
return &manifest.Method{
|
|
Name: name,
|
|
Parameters: ps,
|
|
ReturnType: ret,
|
|
}
|
|
}
|
|
|
|
func newMethodAndPrice(f interop.Method, cpuFee int64, flags callflag.CallFlag) *interop.MethodAndPrice {
|
|
return &interop.MethodAndPrice{
|
|
Func: f,
|
|
CPUFee: cpuFee,
|
|
RequiredFlags: flags,
|
|
}
|
|
}
|
|
|
|
func toBigInt(s stackitem.Item) *big.Int {
|
|
bi, err := s.TryInteger()
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
return bi
|
|
}
|
|
|
|
func toUint160(s stackitem.Item) util.Uint160 {
|
|
buf, err := s.TryBytes()
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
u, err := util.Uint160DecodeBytesBE(buf)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
return u
|
|
}
|
|
|
|
func toUint32(s stackitem.Item) uint32 {
|
|
bigInt := toBigInt(s)
|
|
if !bigInt.IsInt64() {
|
|
panic("bigint is not an int64")
|
|
}
|
|
int64Value := bigInt.Int64()
|
|
if int64Value < 0 || int64Value > math.MaxUint32 {
|
|
panic("bigint does not fit into uint32")
|
|
}
|
|
return uint32(int64Value)
|
|
}
|