Merge pull request #2639 from nspcc-dev/oracle-fix

Oracle fix

internal/contracts/contracts.go

@@ -21,8 +21,10 @@ var (
 	helper2ContractNEFPath      = filepath.Join("management_helper", "management_helper2.nef")
 	helper2ContractManifestPath = filepath.Join("management_helper", "management_helper2.manifest.json")
 
-	oracleContractNEFPath      = filepath.Join("oracle_contract", "oracle.nef")
-	oracleContractManifestPath = filepath.Join("oracle_contract", "oracle.manifest.json")
+	oracleContractModPath      = "oracle_contract"
+	oracleContractYAMLPath     = filepath.Join(oracleContractModPath, "oracle.yml")
+	oracleContractNEFPath      = filepath.Join(oracleContractModPath, "oracle.nef")
+	oracleContractManifestPath = filepath.Join(oracleContractModPath, "oracle.manifest.json")
 )
 
 // GetTestContractState reads 2 pre-compiled contracts generated by

internal/contracts/contracts_test.go

@@ -41,81 +41,10 @@ func TestGenerateHelperContracts(t *testing.T) {
 // Oracle and StdLib native hashes and saves the generated NEF and manifest to `oracle_contract` folder.
 // Set `saveState` flag to true and run the test to rewrite NEF and manifest files.
 func generateOracleContract(t *testing.T, saveState bool) {
-	bc, validator, committee := chain.NewMultiWithCustomConfig(t, func(c *config.ProtocolConfiguration) {
-		c.P2PSigExtensions = true
-	})
-	e := neotest.NewExecutor(t, bc, validator, committee)
-
-	oracleHash := e.NativeHash(t, nativenames.Oracle)
-	stdHash := e.NativeHash(t, nativenames.StdLib)
-
-	w := io.NewBufBinWriter()
-	emit.Int(w.BinWriter, 5)
-	emit.Opcodes(w.BinWriter, opcode.PACK)
-	emit.Int(w.BinWriter, int64(callflag.All))
-	emit.String(w.BinWriter, "request")
-	emit.Bytes(w.BinWriter, oracleHash.BytesBE())
-	emit.Syscall(w.BinWriter, interopnames.SystemContractCall)
-	emit.Opcodes(w.BinWriter, opcode.DROP)
-	emit.Opcodes(w.BinWriter, opcode.RET)
-
-	// `handle` method aborts if len(userData) == 2 and does NOT perform witness checks
-	// for the sake of contract code simplicity (the contract is used in multiple testchains).
-	offset := w.Len()
-
-	emit.Opcodes(w.BinWriter, opcode.OVER)
-	emit.Opcodes(w.BinWriter, opcode.SIZE)
-	emit.Int(w.BinWriter, 2)
-	emit.Instruction(w.BinWriter, opcode.JMPNE, []byte{3})
-	emit.Opcodes(w.BinWriter, opcode.ABORT)
-	emit.Int(w.BinWriter, 4) // url, userData, code, result
-	emit.Opcodes(w.BinWriter, opcode.PACK)
-	emit.Int(w.BinWriter, 1)                                            // 1 byte (args count for `serialize`)
-	emit.Opcodes(w.BinWriter, opcode.PACK)                              // 1 byte (pack args into array for `serialize`)
-	emit.AppCallNoArgs(w.BinWriter, stdHash, "serialize", callflag.All) // 39 bytes
-	emit.String(w.BinWriter, "lastOracleResponse")
-	emit.Syscall(w.BinWriter, interopnames.SystemStorageGetContext)
-	emit.Syscall(w.BinWriter, interopnames.SystemStoragePut)
-	emit.Opcodes(w.BinWriter, opcode.RET)
-
-	m := manifest.NewManifest("TestOracle")
-	m.ABI.Methods = []manifest.Method{
-		{
-			Name:   "requestURL",
-			Offset: 0,
-			Parameters: []manifest.Parameter{
-				manifest.NewParameter("url", smartcontract.StringType),
-				manifest.NewParameter("filter", smartcontract.StringType),
-				manifest.NewParameter("callback", smartcontract.StringType),
-				manifest.NewParameter("userData", smartcontract.AnyType),
-				manifest.NewParameter("gasForResponse", smartcontract.IntegerType),
-			},
-			ReturnType: smartcontract.VoidType,
-		},
-		{
-			Name:   "handle",
-			Offset: offset,
-			Parameters: []manifest.Parameter{
-				manifest.NewParameter("url", smartcontract.StringType),
-				manifest.NewParameter("userData", smartcontract.AnyType),
-				manifest.NewParameter("code", smartcontract.IntegerType),
-				manifest.NewParameter("result", smartcontract.ByteArrayType),
-			},
-			ReturnType: smartcontract.VoidType,
-		},
-	}
-
-	perm := manifest.NewPermission(manifest.PermissionHash, oracleHash)
-	perm.Methods.Add("request")
-	m.Permissions = append(m.Permissions, *perm)
-
-	// Generate NEF file.
-	script := w.Bytes()
-	ne, err := nef.NewFile(script)
-	require.NoError(t, err)
+	ctr := neotest.CompileFile(t, util.Uint160{}, oracleContractModPath, oracleContractYAMLPath)
 
 	// Write NEF file.
-	bytes, err := ne.Bytes()
+	bytes, err := ctr.NEF.Bytes()
 	require.NoError(t, err)
 	if saveState {
 		err = os.WriteFile(oracleContractNEFPath, bytes, os.ModePerm)
@@ -123,7 +52,7 @@ func generateOracleContract(t *testing.T, saveState bool) {
 	}
 
 	// Write manifest file.
-	mData, err := json.Marshal(m)
+	mData, err := json.Marshal(ctr.Manifest)
 	require.NoError(t, err)
 	if saveState {
 		err = os.WriteFile(oracleContractManifestPath, mData, os.ModePerm)

internal/contracts/oracle_contract/go.mod

@@ -0,0 +1,5 @@
+module github.com/nspcc-dev/neo-go/examples/oracle
+
+go 1.17
+
+require github.com/nspcc-dev/neo-go/pkg/interop v0.0.0-20220809123759-3094d3e0c14b

internal/contracts/oracle_contract/go.sum

@@ -0,0 +1,2 @@
+github.com/nspcc-dev/neo-go/pkg/interop v0.0.0-20220809123759-3094d3e0c14b h1:J7QZNmnO84esVuPbBo88fwAG4XVnDjlSTiO1ewLNCkQ=
+github.com/nspcc-dev/neo-go/pkg/interop v0.0.0-20220809123759-3094d3e0c14b/go.mod h1:23bBw0v6pBYcrWs8CBEEDIEDJNbcFoIh8pGGcf2Vv8s=

internal/contracts/oracle_contract/oracle.go

@@ -0,0 +1,42 @@
+package oraclecontract
+
+import (
+	"github.com/nspcc-dev/neo-go/pkg/interop"
+	"github.com/nspcc-dev/neo-go/pkg/interop/contract"
+	"github.com/nspcc-dev/neo-go/pkg/interop/native/oracle"
+	"github.com/nspcc-dev/neo-go/pkg/interop/native/std"
+	"github.com/nspcc-dev/neo-go/pkg/interop/runtime"
+	"github.com/nspcc-dev/neo-go/pkg/interop/storage"
+	"github.com/nspcc-dev/neo-go/pkg/interop/util"
+)
+
+// RequestURL accepts a complete set of parameters to make an oracle request and
+// performs it.
+func RequestURL(url string, filter []byte, callback string, userData interface{}, gasForResponse int) {
+	oracle.Request(url, filter, callback, userData, gasForResponse)
+}
+
+// Handle is a response handler that writes response data to the storage.
+func Handle(url string, data interface{}, code int, res []byte) {
+	// ABORT if len(data) == 2, some tests use this feature.
+	if data != nil && len(data.(string)) == 2 {
+		util.Abort()
+	}
+	params := []interface{}{url, data, code, res}
+	storage.Put(storage.GetContext(), "lastOracleResponse", std.Serialize(params))
+}
+
+// HandleRecursive invokes oracle.finish again to test Oracle reentrance.
+func HandleRecursive(url string, data interface{}, code int, res []byte) {
+	// Regular safety check.
+	callingHash := runtime.GetCallingScriptHash()
+	if !callingHash.Equals(oracle.Hash) {
+		panic("not called from oracle contract")
+	}
+
+	runtime.Notify("Invocation")
+	if runtime.GetInvocationCounter() == 1 {
+		// We provide no wrapper for finish in interops, it's not usually needed.
+		contract.Call(interop.Hash160(oracle.Hash), "finish", contract.All)
+	}
+}

internal/contracts/oracle_contract/oracle.manifest.json

@@ -1 +1 @@
-{"name":"TestOracle","abi":{"methods":[{"name":"requestURL","offset":0,"parameters":[{"name":"url","type":"String"},{"name":"filter","type":"String"},{"name":"callback","type":"String"},{"name":"userData","type":"Any"},{"name":"gasForResponse","type":"Integer"}],"returntype":"Void","safe":false},{"name":"handle","offset":41,"parameters":[{"name":"url","type":"String"},{"name":"userData","type":"Any"},{"name":"code","type":"Integer"},{"name":"result","type":"ByteArray"}],"returntype":"Void","safe":false}],"events":[]},"features":{},"groups":[],"permissions":[{"contract":"0xfe924b7cfe89ddd271abaf7210a80a7e11178758","methods":["request"]}],"supportedstandards":[],"trusts":[],"extra":null}
+{"name":"Oracle test","abi":{"methods":[{"name":"handle","offset":14,"parameters":[{"name":"url","type":"String"},{"name":"data","type":"Any"},{"name":"code","type":"Integer"},{"name":"res","type":"ByteArray"}],"returntype":"Void","safe":false},{"name":"handleRecursive","offset":89,"parameters":[{"name":"url","type":"String"},{"name":"data","type":"Any"},{"name":"code","type":"Integer"},{"name":"res","type":"ByteArray"}],"returntype":"Void","safe":false},{"name":"requestURL","offset":0,"parameters":[{"name":"url","type":"String"},{"name":"filter","type":"ByteArray"},{"name":"callback","type":"String"},{"name":"userData","type":"Any"},{"name":"gasForResponse","type":"Integer"}],"returntype":"Void","safe":false}],"events":[{"name":"Invocation","parameters":null}]},"features":{},"groups":[],"permissions":[{"contract":"*","methods":["request","finish"]}],"supportedstandards":[],"trusts":[],"extra":null}

internal/contracts/oracle_contract/oracle.yml

@@ -0,0 +1,7 @@
+name: "Oracle test"
+sourceurl: https://github.com/nspcc-dev/neo-go/
+supportedstandards: []
+events:
+  - name: Invocation
+permissions:
+  - methods: ["request", "finish"]

pkg/core/native/native_test/oracle_test.go

@@ -15,6 +15,7 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
 	"github.com/nspcc-dev/neo-go/pkg/neotest"
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract/trigger"
 	"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
 	"github.com/stretchr/testify/require"
 )
@@ -151,6 +152,15 @@ func TestOracle_Request(t *testing.T) {
 		require.Error(t, err)
 		require.True(t, strings.Contains(err.Error(), "oracle tx points to invalid request"))
 	})
+	t.Run("Reentrant", func(t *testing.T) {
+		putOracleRequest(t, helperValidatorInvoker, "url", nil, "handleRecursive", []byte{}, gasForResponse)
+		tx := prepareResponseTx(t, 2)
+		e.AddNewBlock(t, tx)
+		e.CheckFault(t, tx.Hash(), "Oracle.finish called from non-entry script")
+		aer, err := e.Chain.GetAppExecResults(tx.Hash(), trigger.Application)
+		require.NoError(t, err)
+		require.Equal(t, 2, len(aer[0].Events)) // OracleResponse + Invocation
+	})
 	t.Run("BadRequest", func(t *testing.T) {
 		t.Run("non-UTF8 url", func(t *testing.T) {
 			putOracleRequest(t, helperValidatorInvoker, "\xff", nil, "", []byte{1, 2}, gasForResponse, "invalid value: not UTF-8")

pkg/core/native/oracle.go

@@ -276,6 +276,12 @@ func (o *Oracle) finish(ic *interop.Context, _ []stackitem.Item) stackitem.Item
 
 // FinishInternal processes an oracle response.
 func (o *Oracle) FinishInternal(ic *interop.Context) error {
+	if ic.VM.Istack().Len() != 2 {
+		return errors.New("Oracle.finish called from non-entry script")
+	}
+	if ic.Invocations[o.Hash] != 1 {
+		return errors.New("Oracle.finish called multiple times")
+	}
 	resp := getResponse(ic.Tx)
 	if resp == nil {
 		return ErrResponseNotFound