neoneo-go/pkg/core/interop_system.go
2021-03-16 16:59:23 +03:00

216 lines
6.2 KiB
Go

package core
import (
"crypto/elliptic"
"errors"
"fmt"
"math"
"github.com/nspcc-dev/neo-go/pkg/core/block"
"github.com/nspcc-dev/neo-go/pkg/core/interop"
"github.com/nspcc-dev/neo-go/pkg/core/native"
"github.com/nspcc-dev/neo-go/pkg/core/state"
"github.com/nspcc-dev/neo-go/pkg/core/transaction"
"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/smartcontract"
"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
)
const (
// MaxStorageKeyLen is the maximum length of a key for storage items.
MaxStorageKeyLen = 64
// MaxStorageValueLen is the maximum length of a value for storage items.
// It is set to be the maximum value for uint16.
MaxStorageValueLen = 65535
)
// StorageContext contains storing id and read/write flag, it's used as
// a context for storage manipulation functions.
type StorageContext struct {
ID int32
ReadOnly bool
}
// StorageFlag represents storage flag which denotes whether the stored value is
// a constant.
type StorageFlag byte
const (
// None is a storage flag for non-constant items.
None StorageFlag = 0
// Constant is a storage flag for constant items.
Constant StorageFlag = 0x01
)
// engineGetScriptContainer returns transaction or block that contains the script
// being run.
func engineGetScriptContainer(ic *interop.Context) error {
var item stackitem.Item
switch t := ic.Container.(type) {
case *transaction.Transaction:
item = native.TransactionToStackItem(t)
case *block.Block:
item = native.BlockToStackItem(t)
default:
return errors.New("unknown script container")
}
ic.VM.Estack().PushVal(item)
return nil
}
// storageDelete deletes stored key-value pair.
func storageDelete(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)
}
if stc.ReadOnly {
return errors.New("StorageContext is read only")
}
ic.VM.AddGas(ic.Chain.GetPolicer().GetStoragePrice())
key := ic.VM.Estack().Pop().Bytes()
return ic.DAO.DeleteStorageItem(stc.ID, key)
}
// storageGet returns stored key-value pair.
func storageGet(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)
}
key := ic.VM.Estack().Pop().Bytes()
si := ic.DAO.GetStorageItem(stc.ID, key)
if si != nil {
ic.VM.Estack().PushVal([]byte(si))
} else {
ic.VM.Estack().PushVal(stackitem.Null{})
}
return nil
}
// storageGetContext returns storage context (scripthash).
func storageGetContext(ic *interop.Context) error {
return storageGetContextInternal(ic, false)
}
// storageGetReadOnlyContext returns read-only context (scripthash).
func storageGetReadOnlyContext(ic *interop.Context) error {
return storageGetContextInternal(ic, true)
}
// storageGetContextInternal is internal version of storageGetContext and
// storageGetReadOnlyContext which allows to specify ReadOnly context flag.
func storageGetContextInternal(ic *interop.Context, isReadOnly bool) error {
contract, err := ic.GetContract(ic.VM.GetCurrentScriptHash())
if err != nil {
return err
}
sc := &StorageContext{
ID: contract.ID,
ReadOnly: isReadOnly,
}
ic.VM.Estack().PushVal(stackitem.NewInterop(sc))
return nil
}
func putWithContext(ic *interop.Context, stc *StorageContext, key []byte, value []byte) error {
if len(key) > MaxStorageKeyLen {
return errors.New("key is too big")
}
if len(value) > MaxStorageValueLen {
return errors.New("value is too big")
}
if stc.ReadOnly {
return errors.New("StorageContext is read only")
}
si := ic.DAO.GetStorageItem(stc.ID, key)
sizeInc := len(value)
if si == nil {
si = state.StorageItem{}
sizeInc = len(key) + len(value)
} else if len(value) != 0 {
if len(value) <= len(si) {
sizeInc = (len(value)-1)/4 + 1
} else if len(si) != 0 {
sizeInc = (len(si)-1)/4 + 1 + len(value) - len(si)
}
}
if !ic.VM.AddGas(int64(sizeInc) * ic.Chain.GetPolicer().GetStoragePrice()) {
return errGasLimitExceeded
}
return ic.DAO.PutStorageItem(stc.ID, key, value)
}
// storagePut puts key-value pair into the storage.
func storagePut(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)
}
key := ic.VM.Estack().Pop().Bytes()
value := ic.VM.Estack().Pop().Bytes()
return putWithContext(ic, stc, key, value)
}
// storageContextAsReadOnly sets given context to read-only mode.
func storageContextAsReadOnly(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)
}
if !stc.ReadOnly {
stx := &StorageContext{
ID: stc.ID,
ReadOnly: true,
}
stc = stx
}
ic.VM.Estack().PushVal(stackitem.NewInterop(stc))
return nil
}
// contractCreateMultisigAccount calculates multisig contract scripthash for a
// given m and a set of public keys.
func contractCreateMultisigAccount(ic *interop.Context) error {
m := ic.VM.Estack().Pop().BigInt()
if !m.IsInt64() || m.Int64() > math.MaxInt32 {
return errors.New("m should fit int32")
}
arr := ic.VM.Estack().Pop().Array()
pubs := make(keys.PublicKeys, len(arr))
for i, pk := range arr {
p, err := keys.NewPublicKeyFromBytes(pk.Value().([]byte), elliptic.P256())
if err != nil {
return err
}
pubs[i] = p
}
script, err := smartcontract.CreateMultiSigRedeemScript(int(m.Int64()), pubs)
if err != nil {
return err
}
ic.VM.Estack().PushVal(hash.Hash160(script).BytesBE())
return nil
}
// contractCreateStandardAccount calculates contract scripthash for a given public key.
func contractCreateStandardAccount(ic *interop.Context) error {
h := ic.VM.Estack().Pop().Bytes()
p, err := keys.NewPublicKeyFromBytes(h, elliptic.P256())
if err != nil {
return err
}
ic.VM.Estack().PushVal(p.GetScriptHash().BytesBE())
return nil
}
// contractGetCallFlags returns current context calling flags.
func contractGetCallFlags(ic *interop.Context) error {
ic.VM.Estack().PushVal(ic.VM.Context().GetCallFlags())
return nil
}