neoneo-go/pkg/core/interop/runtime/engine.go
2022-12-07 17:29:09 +03:00

171 lines
5.3 KiB
Go

package runtime
import (
"errors"
"fmt"
"math/big"
"github.com/nspcc-dev/neo-go/pkg/core/interop"
"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
"github.com/nspcc-dev/neo-go/pkg/vm"
"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
"go.uber.org/zap"
)
type itemable interface {
ToStackItem() stackitem.Item
}
const (
// MaxEventNameLen is the maximum length of a name for event.
MaxEventNameLen = 32
// MaxNotificationSize is the maximum length of a runtime log message.
MaxNotificationSize = 1024
// SystemRuntimeLogMessage represents log entry message used for output
// of the System.Runtime.Log syscall.
SystemRuntimeLogMessage = "runtime log"
)
// GetExecutingScriptHash returns executing script hash.
func GetExecutingScriptHash(ic *interop.Context) error {
return ic.VM.PushContextScriptHash(0)
}
// GetCallingScriptHash returns calling script hash.
// While Executing and Entry script hashes are always valid for non-native contracts,
// Calling hash is set explicitly when native contracts are used, because when switching from
// one native to another, no operations are performed on invocation stack.
func GetCallingScriptHash(ic *interop.Context) error {
h := ic.VM.GetCallingScriptHash()
ic.VM.Estack().PushItem(stackitem.NewByteArray(h.BytesBE()))
return nil
}
// GetEntryScriptHash returns entry script hash.
func GetEntryScriptHash(ic *interop.Context) error {
return ic.VM.PushContextScriptHash(len(ic.VM.Istack()) - 1)
}
// GetScriptContainer returns transaction or block that contains the script
// being run.
func GetScriptContainer(ic *interop.Context) error {
c, ok := ic.Container.(itemable)
if !ok {
return errors.New("unknown script container")
}
ic.VM.Estack().PushItem(c.ToStackItem())
return nil
}
// Platform returns the name of the platform.
func Platform(ic *interop.Context) error {
ic.VM.Estack().PushItem(stackitem.NewByteArray([]byte("NEO")))
return nil
}
// GetTrigger returns the script trigger.
func GetTrigger(ic *interop.Context) error {
ic.VM.Estack().PushItem(stackitem.NewBigInteger(big.NewInt(int64(ic.Trigger))))
return nil
}
// Notify should pass stack item to the notify plugin to handle it, but
// in neo-go the only meaningful thing to do here is to log.
func Notify(ic *interop.Context) error {
name := ic.VM.Estack().Pop().String()
elem := ic.VM.Estack().Pop()
args := elem.Array()
if len(name) > MaxEventNameLen {
return fmt.Errorf("event name must be less than %d", MaxEventNameLen)
}
curHash := ic.VM.GetCurrentScriptHash()
ctr, err := ic.GetContract(curHash)
if err != nil {
return errors.New("notifications are not allowed in dynamic scripts")
}
ev := ctr.Manifest.ABI.GetEvent(name)
if ev == nil {
ic.Log.Info("bad notification", zap.String("contract", curHash.StringLE()), zap.String("event", name), zap.Error(fmt.Errorf("event %s does not exist", name)))
} else {
err = ev.CheckCompliance(args)
if err != nil {
ic.Log.Info("bad notification", zap.String("contract", curHash.StringLE()), zap.String("event", name), zap.Error(err))
}
}
// But it has to be serializable, otherwise we either have some broken
// (recursive) structure inside or an interop item that can't be used
// outside of the interop subsystem anyway.
bytes, err := ic.DAO.GetItemCtx().Serialize(elem.Item(), false)
if err != nil {
return fmt.Errorf("bad notification: %w", err)
}
if len(bytes) > MaxNotificationSize {
return fmt.Errorf("notification size shouldn't exceed %d", MaxNotificationSize)
}
ic.AddNotification(curHash, name, stackitem.DeepCopy(stackitem.NewArray(args), true).(*stackitem.Array))
return nil
}
// LoadScript takes a script and arguments from the stack and loads it into the VM.
func LoadScript(ic *interop.Context) error {
script := ic.VM.Estack().Pop().Bytes()
fs := callflag.CallFlag(int32(ic.VM.Estack().Pop().BigInt().Int64()))
if fs&^callflag.All != 0 {
return errors.New("call flags out of range")
}
args := ic.VM.Estack().Pop().Array()
err := vm.IsScriptCorrect(script, nil)
if err != nil {
return fmt.Errorf("invalid script: %w", err)
}
fs = ic.VM.Context().GetCallFlags() & callflag.ReadOnly & fs
ic.VM.LoadDynamicScript(script, fs)
for e, i := ic.VM.Estack(), len(args)-1; i >= 0; i-- {
e.PushItem(args[i])
}
return nil
}
// Log logs the message passed.
func Log(ic *interop.Context) error {
state := ic.VM.Estack().Pop().String()
if len(state) > MaxNotificationSize {
return fmt.Errorf("message length shouldn't exceed %v", MaxNotificationSize)
}
var txHash string
if ic.Tx != nil {
txHash = ic.Tx.Hash().StringLE()
}
ic.Log.Info(SystemRuntimeLogMessage,
zap.String("tx", txHash),
zap.String("script", ic.VM.GetCurrentScriptHash().StringLE()),
zap.String("msg", state))
return nil
}
// GetTime returns timestamp of the block being verified, or the latest
// one in the blockchain if no block is given to Context.
func GetTime(ic *interop.Context) error {
ic.VM.Estack().PushItem(stackitem.NewBigInteger(new(big.Int).SetUint64(ic.Block.Timestamp)))
return nil
}
// BurnGas burns GAS to benefit Neo ecosystem.
func BurnGas(ic *interop.Context) error {
gas := ic.VM.Estack().Pop().BigInt()
if !gas.IsInt64() {
return errors.New("invalid GAS value")
}
g := gas.Int64()
if g <= 0 {
return errors.New("GAS must be positive")
}
if !ic.VM.AddGas(g) {
return errors.New("GAS limit exceeded")
}
return nil
}