From dd707f00784dff2e3abe94d86f2cd6b6eacc627f Mon Sep 17 00:00:00 2001
From: Richard Meissner <msc.meissner@gmail.com>
Date: Tue, 2 Oct 2018 15:48:56 +0200
Subject: [PATCH] add check if nonce or code at address

---
 lib/opFns.js   | 11 ++++++----
 lib/runCall.js | 55 ++++++++++++++++++++++++++++++++------------------
 package.json   |  2 +-
 3 files changed, 43 insertions(+), 25 deletions(-)

diff --git a/lib/opFns.js b/lib/opFns.js
index 039530de5b..2d94414b20 100644
--- a/lib/opFns.js
+++ b/lib/opFns.js
@@ -520,7 +520,7 @@ module.exports = {
     checkOutOfGas(runState, options)
     makeCall(runState, options, localOpts, done)
   },
-  CREATE2: function (value, offset, length, runState, done) {
+  CREATE2: function (value, offset, length, salt, runState, done) {
     if (!runState._common.gteHardfork('constantinople')) {
       trap(ERROR.INVALID_OPCODE)
     }
@@ -534,17 +534,20 @@ module.exports = {
     // set up config
     var options = {
       value: value,
-      data: data
+      data: data,
+      salt: salt.toBuffer('be', 32)
     }
 
     var localOpts = {
       inOffset: offset,
       inLength: length,
       outOffset: new BN(0),
-      outLength: new BN(0),
-      salt: salt
+      outLength: new BN(0)
     }
 
+    // Deduct gas costs for hashing
+    // TODO this is not yet part of the tests
+    // subGas(runState, new BN(runState._common.param('gasPrices', 'sha3Word')).imul(length.divCeil(new BN(32))))
     checkCallMemCost(runState, options, localOpts)
     checkOutOfGas(runState, options)
     makeCall(runState, options, localOpts, done)
diff --git a/lib/runCall.js b/lib/runCall.js
index bdc23750b4..709cd1e488 100644
--- a/lib/runCall.js
+++ b/lib/runCall.js
@@ -5,6 +5,7 @@ const BN = ethUtil.BN
 const exceptions = require('./exceptions.js')
 
 const ERROR = exceptions.ERROR
+const EMPTY_CODE_HASH = ethUtil.keccak256()
 
 /**
  * runs a CALL operation
@@ -69,39 +70,53 @@ module.exports = function (opts, cb) {
       code = txData
       txData = undefined
       var newNonce = new BN(account.nonce).subn(1)
-       
+      
       if (salt) {
         createdAddress = toAddress = ethUtil.generateAddress2(caller, salt, code)
       } else {
         createdAddress = toAddress = ethUtil.generateAddress(caller, newNonce.toArray())
       }
 
-      stateManager.clearContractStorage(createdAddress, function (err) {
+      stateManager.getAccount(createdAddress, function (err, account) {
         if (err) {
           done(err)
+          return
         }
 
-        async.series([
-          newContractEvent,
-          getAccount
-        ], done)
-
-        function newContractEvent (callback) {
-          self.emit('newContract', {
-            address: createdAddress,
-            code: code
-          }, callback)
+        if ((account.nonce && new BN(account.nonce) > 0) || account.codeHash.compare(EMPTY_CODE_HASH) != 0) {
+          done(ERROR.INVALID_OPCODE)
+          return
         }
 
-        function getAccount (callback) {
-          stateManager.getAccount(createdAddress, function (err, account) {
-            toAccount = account
-            const NONCE_OFFSET = 1
-            toAccount.nonce = new BN(toAccount.nonce).addn(NONCE_OFFSET).toArrayLike(Buffer)
-            callback(err)
-          })
-        }
+        stateManager.clearContractStorage(createdAddress, function (err) {
+          if (err) {
+            done(err)
+            return
+          }
+  
+          async.series([
+            newContractEvent,
+            getAccount
+          ], done)
+  
+          function newContractEvent (callback) {
+            self.emit('newContract', {
+              address: createdAddress,
+              code: code
+            }, callback)
+          }
+  
+          function getAccount (callback) {
+            stateManager.getAccount(createdAddress, function (err, account) {
+              toAccount = account
+              const NONCE_OFFSET = 1
+              toAccount.nonce = new BN(toAccount.nonce).addn(NONCE_OFFSET).toArrayLike(Buffer)
+              callback(err)
+            })
+          }
+        })
       })
+      
     } else {
       // else load the `to` account
       toAccount = stateManager.cache.get(toAddress)
diff --git a/package.json b/package.json
index 3f1e5c9229..0767b4385c 100644
--- a/package.json
+++ b/package.json
@@ -39,7 +39,7 @@
     "ethereumjs-account": "^2.0.3",
     "ethereumjs-block": "~2.0.1",
     "ethereumjs-common": "~0.4.0",
-    "ethereumjs-util": "git+https://github.com/ethereumjs/ethereumjs-util#create2",
+    "ethereumjs-util": "git+https://github.com/ethereumjs/ethereumjs-util.git#create2",
     "fake-merkle-patricia-tree": "^1.0.1",
     "functional-red-black-tree": "^1.0.1",
     "merkle-patricia-tree": "^2.1.2",