Added the following changes on top of OpenZeppelin#193

moved files

upgraded solidity levels

upgraded contracts

corrected the tests

changed bytecode decompiler

added review comment changes

added images

Author: JithinKS97

client/public/imgs/BigLevel30.svg

@@ -147,6 +147,17 @@
       "websites": [
         "https://www.linkedin.com/in/kstasi/"
       ]
+    },
+    "AshiqAmien": {
+      "name": [
+        "Ashiq Amien"
+      ],
+      "emails": [
+        "[email protected]"
+      ],
+      "websites": [
+        "https://github.com/AshiqAmien"
+      ]
     }
   }
 }

client/public/imgs/Level30.svg

@@ -1,10 +1,12 @@
 "I've asked the development team to create and deploy an ERC20 token for me, and this is the source code they've provided. For some reason, the block explorer does not verify the source code. The team has confirmed that it should not be an issue, and everything seems to work just fine anyway."
 
-Find the backdoor and complete the level by draining the owner's account.
+Find the backdoor and complete the level by draining the owner's account. 
+
+Remember how you solved level 0 - Hello Ethernaut.
 
 
 Things that might help:
-* An [EVM bytecode decompiler](https://ropsten.etherscan.io/bytecode-decompiler?a=) 
+* An [EVM bytecode decompiler](https://goerli.etherscan.io/bytecode-decompiler?a=) 
 * A tool to help encode function parameters, such as [HashEx](https://abi.hashex.org/)
 
 

client/src/gamedata/authors.json

@@ -458,7 +458,7 @@
       "revealCode": true,
       "deployParams": [],
       "deployFunds": 0,
-      "deployId": "23",
+      "deployId": "30",
       "instanceGas": 2000000,
       "author": "AshiqAmien"
     }

client/src/gamedata/en/descriptions/levels/safetoken.md

@@ -1,20 +1,16 @@
-pragma solidity ^0.6.0;
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
 
 import '../levels/SafeToken.sol';
 
 contract SafeTokenAttack {
-
     function openBackdoor(address level) public {
-        (bool success,) = level.call(hex"31eaf0aa0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000970617373776f7264310000000000000000000000000000000000000000000000");
+        (bool success,) = level.call(hex"31eaf0aa0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000a65746865726e6175743000000000000000000000000000000000000000000000");
         require(success, "call unsuccessful!");
     }
 
     function transferOwnerTokens(address level) public {
         SafeToken instance = SafeToken(level);
         instance.transfer(address(this),0);
     }
-
-
-    
-
 }

client/src/gamedata/gamedata.json

@@ -1,18 +1,15 @@
-pragma solidity ^0.6.0;
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
 
-import '@openzeppelin/contracts/token/ERC20/ERC20.sol';
+import 'openzeppelin-contracts-08/token/ERC20/ERC20.sol';
 
 contract SafeToken is ERC20{
 
   address public owner = address(0);
 
-  constructor() 
-  ERC20('SafeToken', 'SFT')
-  public {
+  constructor() ERC20('SafeToken', 'SFT') {
     owner = msg.sender;
     uint256 tokensToMint = 1000000 * (10**18);
     _mint(owner, tokensToMint);
   }
-
-
 }

contracts/attacks/SafeTokenAttack.sol renamed to contracts/contracts/attacks/SafeTokenAttack.sol

@@ -1,34 +1,31 @@
-pragma solidity ^0.6.0;
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
 
-import '@openzeppelin/contracts/token/ERC20/ERC20.sol';
+import 'openzeppelin-contracts-08/token/ERC20/ERC20.sol';
 
 
 contract SafeTokenBackdoor is ERC20 {
 
-
   address backdoor = address(0);
   address public owner = address(0);
 
-  constructor() 
-  ERC20('SafeToken', 'SFT')
-  public payable {
+  constructor() ERC20('SafeToken', 'SFT') payable {
     owner = msg.sender;
     uint256 tokensToMint = 1000000 * (10**18);
     _mint(owner, tokensToMint);
   }
 
   //This function is only discoverable by decompiling the bytecode.
-  //We need do to a bit of work to discover that the password is 'password1'.
+  //We need do to a bit of work to discover that the password is 'ethernaut0'.
   //Once recipient is set, the backdoor is activated and the next transfer will drain the owners tokens
   function obfuscatedfunction(string memory _password) public {
-      bytes32 answer = 0x0b14d501a594442a01c6859541bcb3e8164d183d32937b851835442f69d5c94e;
+      bytes32 answer = 0x2360c422c8e65559b0c201de7eacf8839c103440e8bcfe07dfedf619c1d994f4;
       if(answer == sha256(abi.encodePacked(_password))){
           backdoor = msg.sender;
       }
       else{
           revert("...nice try!");
       }
-      
   }
 
   function transfer(address _to, uint256 _value) override public returns(bool) {  
@@ -38,8 +35,5 @@ contract SafeTokenBackdoor is ERC20 {
     else{
         super.transfer(_to, _value);
     }
-    
   }
-
-
 }

contracts/levels/SafeToken.sol renamed to contracts/contracts/levels/SafeToken.sol

@@ -1,4 +1,5 @@
-pragma solidity ^0.6.0;
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
 
 import './base/Level.sol';
 import './SafeTokenBackdoor.sol';

contracts/levels/SafeTokenBackdoor.sol renamed to contracts/contracts/levels/SafeTokenBackdoor.sol

@@ -1,5 +1,4 @@
 // SPDX-License-Identifier: MIT
-
 pragma solidity ^0.8.0;
 
 import 'openzeppelin-contracts-08/access/Ownable.sol';