From 429cc7827b23c943173affb579448895831d8e43 Mon Sep 17 00:00:00 2001
From: "zilong.dai" <2840478265@qq.com>
Date: Thu, 31 Oct 2024 18:46:54 +0800
Subject: [PATCH] limit 1 OP_CHECKZKPVERIFY per script

---
 src/script/interpreter.cpp | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/script/interpreter.cpp b/src/script/interpreter.cpp
index 7fe0eb8be01..b13e596936a 100644
--- a/src/script/interpreter.cpp
+++ b/src/script/interpreter.cpp
@@ -255,6 +255,7 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, un
     static const valtype vchFalse(0);
     static const valtype vchZero(0);
     static const valtype vchTrue(1, 1);
+    bool zkpOpIsUsed = false;
 
     CScript::const_iterator pc = script.begin();
     CScript::const_iterator pend = script.end();
@@ -1027,6 +1028,14 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, un
                 break;
                 case OP_CHECKZKPVERIFY:
                 {
+                    if (zkpOpIsUsed)
+                    {
+                        return set_error(serror, SCRIPT_ERR_BAD_OPCODE);
+                    }else
+                    {
+                        zkpOpIsUsed = true;
+                    }
+                    
                     // Ensure stack has enough elements for the groth16 proof verification
                     if (stack.size() < 12)
                         return set_error(serror, SCRIPT_ERR_INVALID_STACK_OPERATION);