Merge pull request #2816 from nspcc-dev/fix-pointer-serialization

Fix pointer serialization

cli/vm/cli.go

@@ -60,15 +60,22 @@ const (
 const (
 	verboseFlagFullName   = "verbose"
 	historicFlagFullName  = "historic"
+	gasFlagFullName       = "gas"
 	backwardsFlagFullName = "backwards"
 	diffFlagFullName      = "diff"
 )
 
-var historicFlag = cli.IntFlag{
+var (
+	historicFlag = cli.IntFlag{
 		Name: historicFlagFullName,
 		Usage: "Height for historic script invocation (for MPT-enabled blockchain configuration with KeepOnlyLatestState setting disabled). " +
 			"Assuming that block N-th is specified as an argument, the historic invocation is based on the storage state of height N and fake currently-accepting block with index N+1.",
-}
+	}
+	gasFlag = cli.Int64Flag{
+		Name:  gasFlagFullName,
+		Usage: "GAS limit for this execution (integer number, satoshi).",
+	}
+)
 
 var commands = []cli.Command{
 	{
@@ -143,8 +150,8 @@ Example:
 	{
 		Name:      "loadnef",
 		Usage:     "Load a NEF-consistent script into the VM optionally attaching to it provided signers with scopes",
-		UsageText: `loadnef [--historic <height>] <file> <manifest> [<signer-with-scope>, ...]`,
-		Flags:     []cli.Flag{historicFlag},
+		UsageText: `loadnef [--historic <height>] [--gas <int>] <file> <manifest> [<signer-with-scope>, ...]`,
+		Flags:     []cli.Flag{historicFlag, gasFlag},
 		Description: `<file> and <manifest> parameters are mandatory.
 
 ` + cmdargs.SignersParsingDoc + `
@@ -156,8 +163,8 @@ Example:
 	{
 		Name:      "loadbase64",
 		Usage:     "Load a base64-encoded script string into the VM optionally attaching to it provided signers with scopes",
-		UsageText: `loadbase64 [--historic <height>] <string> [<signer-with-scope>, ...]`,
-		Flags:     []cli.Flag{historicFlag},
+		UsageText: `loadbase64 [--historic <height>] [--gas <int>] <string> [<signer-with-scope>, ...]`,
+		Flags:     []cli.Flag{historicFlag, gasFlag},
 		Description: `<string> is mandatory parameter.
 
 ` + cmdargs.SignersParsingDoc + `
@@ -169,8 +176,8 @@ Example:
 	{
 		Name:      "loadhex",
 		Usage:     "Load a hex-encoded script string into the VM optionally attaching to it provided signers with scopes",
-		UsageText: `loadhex [--historic <height>] <string> [<signer-with-scope>, ...]`,
-		Flags:     []cli.Flag{historicFlag},
+		UsageText: `loadhex [--historic <height>] [--gas <int>] <string> [<signer-with-scope>, ...]`,
+		Flags:     []cli.Flag{historicFlag, gasFlag},
 		Description: `<string> is mandatory parameter.
 
 ` + cmdargs.SignersParsingDoc + `
@@ -182,8 +189,8 @@ Example:
 	{
 		Name:      "loadgo",
 		Usage:     "Compile and load a Go file with the manifest into the VM optionally attaching to it provided signers with scopes",
-		UsageText: `loadgo [--historic <height>] <file> [<signer-with-scope>, ...]`,
-		Flags:     []cli.Flag{historicFlag},
+		UsageText: `loadgo [--historic <height>] [--gas <int>] <file> [<signer-with-scope>, ...]`,
+		Flags:     []cli.Flag{historicFlag, gasFlag},
 		Description: `<file> is mandatory parameter.
 
 ` + cmdargs.SignersParsingDoc + `
@@ -195,10 +202,13 @@ Example:
 	{
 		Name:      "loadtx",
 		Usage:     "Load transaction into the VM from chain or from parameter context file",
-		UsageText: `loadtx [--historic <height>] <file-or-hash>`,
-		Flags:     []cli.Flag{historicFlag},
+		UsageText: `loadtx [--historic <height>] [--gas <int>] <file-or-hash>`,
+		Flags:     []cli.Flag{historicFlag, gasFlag},
 		Description: `Load transaction into the VM from chain or from parameter context file.
-The transaction script will be loaded into VM; the resulting execution context will use the provided transaction as script container including its signers, hash and nonce.
+   The transaction script will be loaded into VM; the resulting execution context
+   will use the provided transaction as script container including its signers,
+   hash and nonce. It'll also use transaction's system fee value as GAS limit if
+   --gas option is not used.
 
 <file-or-hash> is mandatory parameter.
 
@@ -209,8 +219,8 @@ Example:
 	{
 		Name:      "loaddeployed",
 		Usage:     "Load deployed contract into the VM from chain optionally attaching to it provided signers with scopes",
-		UsageText: `loaddeployed [--historic <height>] <hash-or-address-or-id>  [<signer-with-scope>, ...]`,
-		Flags:     []cli.Flag{historicFlag},
+		UsageText: `loaddeployed [--historic <height>] [--gas <int>] <hash-or-address-or-id>  [<signer-with-scope>, ...]`,
+		Flags:     []cli.Flag{historicFlag, gasFlag},
 		Description: `Load deployed contract into the VM from chain optionally attaching to it provided signers with scopes.
 If '--historic' flag specified, then the historic contract state (historic script and manifest) will be loaded.
 
@@ -640,12 +650,22 @@ func handleSlots(c *cli.Context) error {
 // prepareVM retrieves --historic flag from context (if set) and resets app state
 // (to the specified historic height if given).
 func prepareVM(c *cli.Context, tx *transaction.Transaction) error {
+	var err error
 	if c.IsSet(historicFlagFullName) {
 		height := c.Int(historicFlagFullName)
-		return resetState(c.App, tx, uint32(height))
+		err = resetState(c.App, tx, uint32(height))
+	} else {
+		err = resetState(c.App, tx)
 	}
-
-	return resetState(c.App, tx)
+	if err != nil {
+		return err
+	}
+	if c.IsSet(gasFlagFullName) {
+		gas := c.Int64(gasFlagFullName)
+		v := getVMFromContext(c.App)
+		v.GasLimit = gas
+	}
+	return nil
 }
 
 func handleLoadNEF(c *cli.Context) error {
@@ -812,6 +832,9 @@ func handleLoadTx(c *cli.Context) error {
 		return err
 	}
 	v := getVMFromContext(c.App)
+	if v.GasLimit == -1 {
+		v.GasLimit = tx.SystemFee
+	}
 	fmt.Fprintf(c.App.Writer, "READY: loaded %d instructions\n", v.Context().LenInstr())
 	changePrompt(c.App)
 	return nil
@@ -856,7 +879,9 @@ func handleLoadDeployed(c *cli.Context) error {
 		return err
 	}
 	ic = getInteropContextFromContext(c.App) // fetch newly-created IC.
+	gasLimit := ic.VM.GasLimit
 	ic.ReuseVM(ic.VM) // clear previously loaded program and context.
+	ic.VM.GasLimit = gasLimit
 	ic.VM.LoadScriptWithHash(cs.NEF.Script, cs.Hash, callflag.All)
 	fmt.Fprintf(c.App.Writer, "READY: loaded %d instructions\n", ic.VM.Context().LenInstr())
 	setManifestInContext(c.App, &cs.Manifest)

cli/vm/cli_test.go

@@ -1118,6 +1118,8 @@ func TestLoadtx(t *testing.T) {
 	e.runProg(t,
 		"loadtx "+tx.Hash().StringLE(), // hash LE
 		"run",
+		"loadtx --gas 10000 "+tx.Hash().StringLE(), // with GAS
+		"run",
 		"loadtx 0x"+tx.Hash().StringLE(), //  hash LE with 0x prefix
 		"run",
 		"loadtx '"+tmp+"'", // Tx from parameter context file.
@@ -1128,6 +1130,8 @@ func TestLoadtx(t *testing.T) {
 	e.checkNextLine(t, "READY: loaded \\d+ instructions")
 	e.checkStack(t, 1)
 	e.checkNextLine(t, "READY: loaded \\d+ instructions")
+	e.checkError(t, errors.New("at instruction 3 (PACK): gas limit is exceeded"))
+	e.checkNextLine(t, "READY: loaded \\d+ instructions")
 	e.checkStack(t, 1)
 	e.checkNextLine(t, "READY: loaded \\d+ instructions")
 	e.checkStack(t, 1)
@@ -1147,6 +1151,8 @@ func TestLoaddeployed(t *testing.T) {
 	e.runProg(t,
 		"loaddeployed "+h.StringLE(), // hash LE
 		"run get 1",
+		"loaddeployed --gas 420000 "+h.StringLE(), // gas-limited
+		"run get 1",
 		"loaddeployed 0x"+h.StringLE(), //  hash LE with 0x prefix
 		"run get 1",
 		"loaddeployed 1", // contract ID
@@ -1172,6 +1178,8 @@ func TestLoaddeployed(t *testing.T) {
 	e.checkNextLine(t, "READY: loaded \\d+ instructions")
 	e.checkStack(t, []byte{2})
 	e.checkNextLine(t, "READY: loaded \\d+ instructions")
+	e.checkError(t, errors.New("at instruction 63 (SYSCALL): failed to invoke syscall 837311890: insufficient amount of gas"))
+	e.checkNextLine(t, "READY: loaded \\d+ instructions")
 	e.checkStack(t, []byte{2})
 	e.checkNextLine(t, "READY: loaded \\d+ instructions")
 	e.checkStack(t, []byte{2})

pkg/vm/stackitem/serialization.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/nspcc-dev/neo-go/pkg/encoding/bigint"
 	"github.com/nspcc-dev/neo-go/pkg/io"
+	"github.com/nspcc-dev/neo-go/pkg/util"
 )
 
 // MaxDeserialized is the maximum number one deserialized item can contain
@@ -168,6 +169,13 @@ func (w *SerializationContext) serialize(item Item) error {
 		} else {
 			return fmt.Errorf("%w: Interop", ErrUnserializable)
 		}
+	case *Pointer:
+		if w.allowInvalid {
+			w.data = append(w.data, byte(PointerT))
+			w.appendVarUint(uint64(t.pos))
+		} else {
+			return fmt.Errorf("%w: Pointer", ErrUnserializable)
+		}
 	case *Array:
 		w.data = append(w.data, byte(ArrayT))
 		if err := w.writeArray(item, t.value, start); err != nil {
@@ -311,6 +319,12 @@ func (r *deserContext) decodeBinary() Item {
 			return NewInterop(nil)
 		}
 		fallthrough
+	case PointerT:
+		if r.allowInvalid {
+			pos := int(r.ReadVarUint())
+			return NewPointerWithHash(pos, nil, util.Uint160{})
+		}
+		fallthrough
 	default:
 		if t == InvalidT && r.allowInvalid {
 			return nil

pkg/vm/stackitem/serialization_test.go

@@ -76,6 +76,7 @@ func TestSerialize(t *testing.T) {
 	})
 	t.Run("invalid", func(t *testing.T) {
 		testSerialize(t, ErrUnserializable, NewInterop(42))
+		testSerialize(t, ErrUnserializable, NewPointer(42, []byte{}))
 		testSerialize(t, ErrUnserializable, nil)
 
 		t.Run("protected interop", func(t *testing.T) {
@@ -93,6 +94,22 @@ func TestSerialize(t *testing.T) {
 			require.NoError(t, r.Err)
 			require.IsType(t, (*Interop)(nil), item)
 		})
+		t.Run("protected pointer", func(t *testing.T) {
+			w := io.NewBufBinWriter()
+			EncodeBinaryProtected(NewPointer(42, []byte{}), w.BinWriter)
+			require.NoError(t, w.Err)
+
+			data := w.Bytes()
+			r := io.NewBinReaderFromBuf(data)
+			DecodeBinary(r)
+			require.Error(t, r.Err)
+
+			r = io.NewBinReaderFromBuf(data)
+			item := DecodeBinaryProtected(r)
+			require.NoError(t, r.Err)
+			require.IsType(t, (*Pointer)(nil), item)
+			require.Equal(t, 42, item.Value())
+		})
 		t.Run("protected nil", func(t *testing.T) {
 			w := io.NewBufBinWriter()
 			EncodeBinaryProtected(nil, w.BinWriter)