From 283157dd71de9441fa5b96c9a91d515a6341bdfb Mon Sep 17 00:00:00 2001
From: Christopher Jeffrey <chjjeffrey@gmail.com>
Date: Fri, 18 Dec 2015 17:50:51 -0800
Subject: [PATCH] add `allowEval` option.

---
 lib/bcoin/script.js | 41 ++++++++++++++++++++++++++++-------------
 1 file changed, 28 insertions(+), 13 deletions(-)

diff --git a/lib/bcoin/script.js b/lib/bcoin/script.js
index 0a4b0114..5a6fa6b0 100644
--- a/lib/bcoin/script.js
+++ b/lib/bcoin/script.js
@@ -198,7 +198,7 @@ script._next = function(to, s, pc) {
   return -1;
 };
 
-script.execute = function execute(s, stack, tx, index) {
+script.execute = function execute(s, stack, tx, index, recurse) {
   s = s.slice();
 
   if (s.length > constants.script.maxOps)
@@ -713,9 +713,6 @@ script.execute = function execute(s, stack, tx, index) {
       }
       case 'checklocktimeverify': {
         // OP_CHECKLOCKTIMEVERIFY = OP_NOP2
-        // input: [[], sig1, sig2, 1]
-        // prev_out: [[lock], 'checklocktimeverify', 'drop',
-        //            'dup', 'hash160', pubkey, 'equalverify', 'checksig']
         if (!tx || stack.length === 0)
           return false;
 
@@ -742,12 +739,30 @@ script.execute = function execute(s, stack, tx, index) {
       }
       case 'eval_': {
         // OP_EVAL = OP_NOP1
-        // var evalScript = script.decode(stack.pop());
-        // if (!Array.isArray(evalScript))
-        //   return false;
-        // var res = script.execute(evalScript, stack, tx, index);
-        // if (!res)
-        //   return false;
+        if (!script.allowEval)
+          break;
+
+        recurse = recurse || 0;
+
+        if (recurse++ > 2)
+          return false;
+
+        var evalScript = stack.pop();
+        if (!Array.isArray(evalScript))
+          return false;
+
+        evalScript = script.decode(evalScript);
+
+        var res = evalScript.some(function(op) {
+          return op === 'codesep';
+        });
+        if (res)
+          return false;
+
+        res = script.execute(evalScript, stack, tx, index, recurse);
+        if (!res)
+          return false;
+
         break;
       }
       default: {
@@ -763,10 +778,10 @@ script.execute = function execute(s, stack, tx, index) {
   return true;
 };
 
-script.exec = function(input, output, tx, i) {
+script.exec = function(input, output, tx, i, recurse) {
   var stack = [];
-  script.execute(input, stack, tx, i);
-  var res = script.execute(output, stack, tx, i);
+  script.execute(input, stack, tx, i, recurse);
+  var res = script.execute(output, stack, tx, i, recurse);
   // if (!res || stack.length === 0 || new bn(stack.pop()).cmp(0) !== 0)
   if (!res || stack.length === 0 || utils.isEqual(stack.pop(), [ 0 ]))
     return false;