neoneo-go/pkg/core/interop_neo.go
2020-11-27 21:47:08 +03:00

243 lines
7.2 KiB
Go

package core
import (
"bytes"
"encoding/base64"
"encoding/json"
"errors"
"fmt"
"math"
"sort"
"github.com/mr-tron/base58"
"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/state"
"github.com/nspcc-dev/neo-go/pkg/smartcontract"
"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/vm"
"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
)
const (
// MaxContractDescriptionLen is the maximum length for contract description.
MaxContractDescriptionLen = 65536
// MaxContractScriptSize is the maximum script size for a contract.
MaxContractScriptSize = 1024 * 1024
// MaxContractParametersNum is the maximum number of parameters for a contract.
MaxContractParametersNum = 252
// MaxContractStringLen is the maximum length for contract metadata strings.
MaxContractStringLen = 252
)
var errGasLimitExceeded = errors.New("gas limit exceeded")
// storageFind finds stored key-value pair.
func storageFind(ic *interop.Context) error {
stcInterface := ic.VM.Estack().Pop().Value()
stc, ok := stcInterface.(*StorageContext)
if !ok {
return fmt.Errorf("%T is not a StorageContext", stcInterface)
}
prefix := ic.VM.Estack().Pop().Bytes()
siMap, err := ic.DAO.GetStorageItemsWithPrefix(stc.ID, prefix)
if err != nil {
return err
}
filteredMap := stackitem.NewMap()
for k, v := range siMap {
filteredMap.Add(stackitem.NewByteArray(append(prefix, []byte(k)...)), stackitem.NewByteArray(v.Value))
}
sort.Slice(filteredMap.Value().([]stackitem.MapElement), func(i, j int) bool {
return bytes.Compare(filteredMap.Value().([]stackitem.MapElement)[i].Key.Value().([]byte),
filteredMap.Value().([]stackitem.MapElement)[j].Key.Value().([]byte)) == -1
})
item := vm.NewMapIterator(filteredMap)
ic.VM.Estack().PushVal(item)
return nil
}
// getNefAndManifestFromVM pops NEF and manifest from the VM's evaluation stack,
// does a lot of checks and returns deserialized structures if succeeds.
func getNefAndManifestFromVM(v *vm.VM) (*nef.File, *manifest.Manifest, error) {
// Always pop both elements.
nefBytes := v.Estack().Pop().BytesOrNil()
manifestBytes := v.Estack().Pop().BytesOrNil()
if err := checkNonEmpty(nefBytes, math.MaxInt32); err != nil { // Upper limits are checked during NEF deserialization.
return nil, nil, fmt.Errorf("invalid NEF file: %w", err)
}
if err := checkNonEmpty(manifestBytes, manifest.MaxManifestSize); err != nil {
return nil, nil, fmt.Errorf("invalid manifest: %w", err)
}
if !v.AddGas(int64(StoragePrice * (len(nefBytes) + len(manifestBytes)))) {
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 {
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
}
// contractCreate creates a contract.
func contractCreate(ic *interop.Context) error {
neff, manif, err := getNefAndManifestFromVM(ic.VM)
if err != nil {
return err
}
if neff == nil {
return errors.New("no valid NEF provided")
}
if manif == nil {
return errors.New("no valid manifest provided")
}
if ic.Tx == nil {
return errors.New("no transaction provided")
}
h := state.CreateContractHash(ic.Tx.Sender(), neff.Script)
contract, err := ic.DAO.GetContractState(h)
if contract != nil && err == nil {
return errors.New("contract already exists")
}
id, err := ic.DAO.GetAndUpdateNextContractID()
if err != nil {
return err
}
if !manif.IsValid(h) {
return errors.New("failed to check contract script hash against manifest")
}
newcontract := &state.Contract{
ID: id,
Hash: h,
Script: neff.Script,
Manifest: *manif,
}
if err := ic.DAO.PutContractState(newcontract); err != nil {
return err
}
cs, err := contractToStackItem(newcontract)
if err != nil {
return fmt.Errorf("cannot convert contract to stack item: %w", err)
}
ic.VM.Estack().PushVal(cs)
return callDeploy(ic, newcontract, false)
}
func checkNonEmpty(b []byte, max int) error {
if b != nil {
if l := len(b); l == 0 {
return errors.New("empty")
} else if l > max {
return fmt.Errorf("len is %d (max %d)", l, max)
}
}
return nil
}
// contractUpdate migrates a contract. This method assumes that Manifest and Script
// of the contract can be updated independently.
func contractUpdate(ic *interop.Context) error {
neff, manif, err := getNefAndManifestFromVM(ic.VM)
if err != nil {
return err
}
if neff == nil && manif == nil {
return errors.New("both NEF and manifest are nil")
}
contract, _ := ic.DAO.GetContractState(ic.VM.GetCurrentScriptHash())
if contract == nil {
return errors.New("contract doesn't exist")
}
// if NEF was provided, update the contract script
if neff != nil {
contract.Script = neff.Script
}
// if manifest was provided, update the contract manifest
if manif != nil {
contract.Manifest = *manif
if !contract.Manifest.IsValid(contract.Hash) {
return errors.New("failed to check contract script hash against new manifest")
}
}
contract.UpdateCounter++
if err := ic.DAO.PutContractState(contract); err != nil {
return fmt.Errorf("failed to update contract: %w", err)
}
return callDeploy(ic, contract, true)
}
func callDeploy(ic *interop.Context, cs *state.Contract, isUpdate bool) error {
md := cs.Manifest.ABI.GetMethod(manifest.MethodDeploy)
if md != nil {
return contract.CallExInternal(ic, cs, manifest.MethodDeploy,
[]stackitem.Item{stackitem.NewBool(isUpdate)}, smartcontract.All, vm.EnsureIsEmpty, nil)
}
return nil
}
// runtimeSerialize serializes top stack item into a ByteArray.
func runtimeSerialize(ic *interop.Context) error {
return vm.RuntimeSerialize(ic.VM)
}
// runtimeDeserialize deserializes ByteArray from a stack into an item.
func runtimeDeserialize(ic *interop.Context) error {
return vm.RuntimeDeserialize(ic.VM)
}
// runtimeEncodeBase64 encodes top stack item into a base64 string.
func runtimeEncodeBase64(ic *interop.Context) error {
src := ic.VM.Estack().Pop().Bytes()
result := base64.StdEncoding.EncodeToString(src)
ic.VM.Estack().PushVal([]byte(result))
return nil
}
// runtimeDecodeBase64 decodes top stack item from base64 string to byte array.
func runtimeDecodeBase64(ic *interop.Context) error {
src := ic.VM.Estack().Pop().String()
result, err := base64.StdEncoding.DecodeString(src)
if err != nil {
return err
}
ic.VM.Estack().PushVal(result)
return nil
}
// runtimeEncodeBase58 encodes top stack item into a base58 string.
func runtimeEncodeBase58(ic *interop.Context) error {
src := ic.VM.Estack().Pop().Bytes()
result := base58.Encode(src)
ic.VM.Estack().PushVal([]byte(result))
return nil
}
// runtimeDecodeBase58 decodes top stack item from base58 string to byte array.
func runtimeDecodeBase58(ic *interop.Context) error {
src := ic.VM.Estack().Pop().String()
result, err := base58.Decode(src)
if err != nil {
return err
}
ic.VM.Estack().PushVal(result)
return nil
}