From ffde45d164f5cbdc4c1472dc2c2453c94d886a9d Mon Sep 17 00:00:00 2001
From: Pavel Karpy <carpawell@nspcc.ru>
Date: Thu, 9 Sep 2021 14:41:04 +0300
Subject: [PATCH] [#807] morph/container: Add opcode check

Parsers return error if unexpected opcode
returns.

Signed-off-by: Pavel Karpy <carpawell@nspcc.ru>
---
 pkg/morph/event/container/put_notary.go | 14 +++++++++++---
 pkg/morph/event/notary.go               |  9 +++++++++
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/pkg/morph/event/container/put_notary.go b/pkg/morph/event/container/put_notary.go
index 0fa4cb5fc..82eee70e6 100644
--- a/pkg/morph/event/container/put_notary.go
+++ b/pkg/morph/event/container/put_notary.go
@@ -50,20 +50,28 @@ var errUnexpectedArgumentAmount = fmt.Errorf("unexpected arguments amount in %s
 
 // ParsePutNotary from NotaryEvent into container event structure.
 func ParsePutNotary(ne event.NotaryEvent) (event.Event, error) {
-	var ev Put
+	var (
+		ev        Put
+		currentOp opcode.Opcode
+	)
 
 	fieldNum := 0
 
 	for _, op := range ne.Params() {
-		switch op.Code() {
-		case opcode.PUSHDATA1, opcode.PUSHDATA2, opcode.PUSHDATA4:
+		currentOp = op.Code()
+
+		switch {
+		case opcode.PUSHDATA1 <= currentOp && currentOp <= opcode.PUSHDATA4:
 			if fieldNum == expectedItemNumPut {
 				return nil, errUnexpectedArgumentAmount
 			}
 
 			fieldSetters[fieldNum](&ev, op.Param())
 			fieldNum++
+		case opcode.PUSH0 <= currentOp && currentOp <= opcode.PUSH16 || currentOp == opcode.PACK:
+			// array packing opcodes. do nothing with it
 		default:
+			return nil, event.UnexpectedOpcode(PutNotaryEvent, op.Code())
 		}
 	}
 
diff --git a/pkg/morph/event/notary.go b/pkg/morph/event/notary.go
index cbb2c5f0d..0319158c2 100644
--- a/pkg/morph/event/notary.go
+++ b/pkg/morph/event/notary.go
@@ -1,8 +1,11 @@
 package event
 
 import (
+	"fmt"
+
 	"github.com/nspcc-dev/neo-go/pkg/network/payload"
 	"github.com/nspcc-dev/neo-go/pkg/util"
+	"github.com/nspcc-dev/neo-go/pkg/vm/opcode"
 )
 
 // NotaryType is a notary event enumeration type.
@@ -39,3 +42,9 @@ func NotaryTypeFromBytes(data []byte) NotaryType {
 func NotaryTypeFromString(str string) NotaryType {
 	return NotaryType(str)
 }
+
+// UnexpectedOpcode returns error when notary parsers
+// get unexpected opcode in contract call.
+func UnexpectedOpcode(method string, op opcode.Opcode) error {
+	return fmt.Errorf("unexpected opcode in %s call: %s", method, op)
+}