From fb7dd53112ae4e3ba47fedeeae4abcf1a9669e9d Mon Sep 17 00:00:00 2001
From: poma <semenov.roma@gmail.com>
Date: Wed, 16 Jun 2021 02:49:38 +0300
Subject: [PATCH] add solidity asserts

---
 contracts/TornadoPool.sol | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/contracts/TornadoPool.sol b/contracts/TornadoPool.sol
index 22d5ba9..b759789 100644
--- a/contracts/TornadoPool.sol
+++ b/contracts/TornadoPool.sol
@@ -121,9 +121,12 @@ contract TornadoPool is ReentrancyGuard {
     int256 extAmount = calculateExternalAmount(_extAmount);
     if (extAmount > 0) {
       require(msg.value == uint256(extAmount), "Incorrect amount of ETH sent on deposit");
-    } else {
+    } else if (extAmount < 0) {
       require(msg.value == 0, "Sent ETH amount should be 0 for withdrawal");
+      require(_extData.recipient != address(0), "Can't withdraw to zero address");
       _extData.recipient.transfer(uint256(-extAmount));
+    } else {
+      require(msg.value == 0, "Sent ETH amount should be 0 for transaction");
     }
 
     if (_fee > 0) {