neo-go/pkg/core/state/contract.go
Roman Khimov f7c5ab4f43 state: check for array length in (*Contract).FromStackItem
Panicing here is not appropriate.
2022-08-16 17:19:47 +03:00

126 lines
3.3 KiB
Go

package state
import (
"errors"
"math"
"math/big"
"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
"github.com/nspcc-dev/neo-go/pkg/io"
"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/util"
"github.com/nspcc-dev/neo-go/pkg/vm/emit"
"github.com/nspcc-dev/neo-go/pkg/vm/opcode"
"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
)
// Contract holds information about a smart contract in the NEO blockchain.
type Contract struct {
ContractBase
UpdateCounter uint16 `json:"updatecounter"`
}
// ContractBase represents a part shared by native and user-deployed contracts.
type ContractBase struct {
ID int32 `json:"id"`
Hash util.Uint160 `json:"hash"`
NEF nef.File `json:"nef"`
Manifest manifest.Manifest `json:"manifest"`
}
// NativeContract holds information about the native contract.
type NativeContract struct {
ContractBase
UpdateHistory []uint32 `json:"updatehistory"`
}
// ToStackItem converts state.Contract to stackitem.Item.
func (c *Contract) ToStackItem() (stackitem.Item, error) {
rawNef, err := c.NEF.Bytes()
if err != nil {
return nil, err
}
m, err := c.Manifest.ToStackItem()
if err != nil {
return nil, err
}
return stackitem.NewArray([]stackitem.Item{
stackitem.Make(c.ID),
stackitem.Make(c.UpdateCounter),
stackitem.NewByteArray(c.Hash.BytesBE()),
stackitem.NewByteArray(rawNef),
m,
}), nil
}
// FromStackItem fills Contract's data from the given stack itemized contract
// representation.
func (c *Contract) FromStackItem(item stackitem.Item) error {
arr, ok := item.Value().([]stackitem.Item)
if !ok {
return errors.New("not an array")
}
if len(arr) != 5 {
return errors.New("invalid structure")
}
bi, ok := arr[0].Value().(*big.Int)
if !ok {
return errors.New("ID is not an integer")
}
if !bi.IsInt64() || bi.Int64() > math.MaxInt32 || bi.Int64() < math.MinInt32 {
return errors.New("ID not in int32 range")
}
c.ID = int32(bi.Int64())
bi, ok = arr[1].Value().(*big.Int)
if !ok {
return errors.New("UpdateCounter is not an integer")
}
if !bi.IsUint64() || bi.Uint64() > math.MaxUint16 {
return errors.New("UpdateCounter not in uint16 range")
}
c.UpdateCounter = uint16(bi.Uint64())
bytes, err := arr[2].TryBytes()
if err != nil {
return err
}
c.Hash, err = util.Uint160DecodeBytesBE(bytes)
if err != nil {
return err
}
bytes, err = arr[3].TryBytes()
if err != nil {
return err
}
c.NEF, err = nef.FileFromBytes(bytes)
if err != nil {
return err
}
m := new(manifest.Manifest)
err = m.FromStackItem(arr[4])
if err != nil {
return err
}
c.Manifest = *m
return nil
}
// CreateContractHash creates a deployed contract hash from the transaction sender
// and the contract script.
func CreateContractHash(sender util.Uint160, checksum uint32, name string) util.Uint160 {
w := io.NewBufBinWriter()
emit.Opcodes(w.BinWriter, opcode.ABORT)
emit.Bytes(w.BinWriter, sender.BytesBE())
emit.Int(w.BinWriter, int64(checksum))
emit.String(w.BinWriter, name)
if w.Err != nil {
panic(w.Err)
}
return hash.Hash160(w.Bytes())
}
// CreateNativeContractHash calculates the hash for the native contract with the
// given name.
func CreateNativeContractHash(name string) util.Uint160 {
return CreateContractHash(util.Uint160{}, 0, name)
}