smartcontract: require manifest serialization in (*Manifest).IsValid

Port the restrictive part of https://github.com/neo-project/neo/pull/2948.

Signed-off-by: Anna Shaleva <shaleva.ann@nspcc.ru>

pkg/smartcontract/manifest/manifest.go

@@ -118,7 +118,19 @@ func (m *Manifest) IsValid(hash util.Uint160) error {
 			return errors.New("duplicate trusted contracts")
 		}
 	}
-	return Permissions(m.Permissions).AreValid()
+	err = Permissions(m.Permissions).AreValid()
+	if err != nil {
+		return err
+	}
+	si, err := m.ToStackItem()
+	if err != nil {
+		return fmt.Errorf("failed to check manifest serialisation: %w", err)
+	}
+	_, err = stackitem.Serialize(si)
+	if err != nil {
+		return fmt.Errorf("manifest is not serializable: %w", err)
+	}
+	return nil
 }
 
 // IsStandardSupported denotes whether the specified standard is supported by the contract.

pkg/smartcontract/manifest/manifest_test.go

@@ -2,6 +2,7 @@ package manifest
 
 import (
 	"encoding/json"
+	"fmt"
 	"math/big"
 	"testing"
 
@@ -243,6 +244,18 @@ func TestIsValid(t *testing.T) {
 			require.Error(t, m.IsValid(contractHash))
 		})
 	})
+	m.Groups = m.Groups[:0]
+
+	t.Run("invalid, unserializable", func(t *testing.T) {
+		for i := 0; i < stackitem.MaxSerialized; i++ {
+			m.ABI.Events = append(m.ABI.Events, Event{
+				Name:       fmt.Sprintf("Event%d", i),
+				Parameters: []Parameter{},
+			})
+		}
+		err := m.IsValid(contractHash)
+		require.ErrorIs(t, err, stackitem.ErrTooBig)
+	})
 }
 
 func TestManifestToStackItem(t *testing.T) {