From 6886991ca67f2c2148429ba87bf7d782f8cb12c8 Mon Sep 17 00:00:00 2001
From: Erik Zhang <erik@neo.org>
Date: Mon, 12 Oct 2020 11:01:22 +0800
Subject: [PATCH] Fix VerifyWitnesses() of native contracts (#1998)

---
 src/neo/SmartContract/Helper.cs | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/src/neo/SmartContract/Helper.cs b/src/neo/SmartContract/Helper.cs
index 0cecf54f8f..d3f841b84d 100644
--- a/src/neo/SmartContract/Helper.cs
+++ b/src/neo/SmartContract/Helper.cs
@@ -4,6 +4,7 @@
 using Neo.Network.P2P.Payloads;
 using Neo.Persistence;
 using Neo.SmartContract.Manifest;
+using Neo.SmartContract.Native;
 using Neo.VM;
 using System;
 using System.Buffers.Binary;
@@ -169,6 +170,7 @@ internal static bool VerifyWitnesses(this IVerifiable verifiable, StoreView snap
                 }
                 else
                 {
+                    if (NativeContract.IsNative(hashes[i])) return false;
                     if (hashes[i] != verifiable.Witnesses[i].ScriptHash) return false;
                     offset = 0;
                 }
@@ -176,7 +178,17 @@ internal static bool VerifyWitnesses(this IVerifiable verifiable, StoreView snap
                 {
                     CallFlags callFlags = verifiable.Witnesses[i].StateDependent ? CallFlags.AllowStates : CallFlags.None;
                     ExecutionContext context = engine.LoadScript(verification, callFlags, offset);
-                    if (init != null) engine.LoadContext(context.Clone(init.Offset), false);
+                    if (NativeContract.IsNative(hashes[i]))
+                    {
+                        using ScriptBuilder sb = new ScriptBuilder();
+                        sb.Emit(OpCode.DEPTH, OpCode.PACK);
+                        sb.EmitPush("verify");
+                        engine.LoadScript(sb.ToArray(), CallFlags.None);
+                    }
+                    else if (init != null)
+                    {
+                        engine.LoadContext(context.Clone(init.Offset), false);
+                    }
                     engine.LoadScript(verifiable.Witnesses[i].InvocationScript, CallFlags.None);
                     if (engine.Execute() == VMState.FAULT) return false;
                     if (engine.ResultStack.Count != 1 || !engine.ResultStack.Pop().GetBoolean()) return false;