From 642cfd01cd1bfcb157fb4a3646208c4fbf2e0a45 Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Mon, 19 Aug 2019 14:10:13 +0300
Subject: [PATCH] process new metadata format for whisper

Solidity >= 0.5.11 has new whisper metadata format
Metadata: Update the swarm hash to the current specification,
changes bzzr0 to bzzr1 and urls to use bzz-raw://

https://github.com/ethereum/solidity/blob/develop/Changelog.md#0511-2019-08-12
---
 .../lib/explorer/smart_contract/verifier.ex   |  8 ++++++
 .../verifier/constructor_arguments.ex         | 10 +++++++
 .../explorer/smart_contract/verifier_test.exs | 27 +++++++++++++++++++
 .../solidity_5.11_new_whisper_metadata.json   |  7 +++++
 4 files changed, 52 insertions(+)
 create mode 100644 apps/explorer/test/support/fixture/smart_contract/solidity_5.11_new_whisper_metadata.json

diff --git a/apps/explorer/lib/explorer/smart_contract/verifier.ex b/apps/explorer/lib/explorer/smart_contract/verifier.ex
index 7aa9957bab..4c2daa680c 100644
--- a/apps/explorer/lib/explorer/smart_contract/verifier.ex
+++ b/apps/explorer/lib/explorer/smart_contract/verifier.ex
@@ -115,6 +115,14 @@ defmodule Explorer.SmartContract.Verifier do
         |> Enum.reverse()
         |> :binary.list_to_bin()
 
+      # Solidity >= 0.5.11 https://github.com/ethereum/solidity/blob/develop/Changelog.md#0511-2019-08-12
+      # Metadata: Update the swarm hash to the current specification, changes bzzr0 to bzzr1 and urls to use bzz-raw://
+      "a265627a7a72315820" <>
+          <<_::binary-size(64)>> <> "64736f6c6343" <> <<_::binary-size(6)>> <> "0032" <> _constructor_arguments ->
+        extracted
+        |> Enum.reverse()
+        |> :binary.list_to_bin()
+
       <<next::binary-size(2)>> <> rest ->
         do_extract_bytecode([next | extracted], rest)
     end
diff --git a/apps/explorer/lib/explorer/smart_contract/verifier/constructor_arguments.ex b/apps/explorer/lib/explorer/smart_contract/verifier/constructor_arguments.ex
index 61167a4559..6e25b3cc52 100644
--- a/apps/explorer/lib/explorer/smart_contract/verifier/constructor_arguments.ex
+++ b/apps/explorer/lib/explorer/smart_contract/verifier/constructor_arguments.ex
@@ -48,6 +48,16 @@ defmodule Explorer.SmartContract.Verifier.ConstructorArguments do
           extract_constructor_arguments(constructor_arguments, passed_constructor_arguments)
         end
 
+      # Solidity >= 0.5.11 https://github.com/ethereum/solidity/blob/develop/Changelog.md#0511-2019-08-12
+      # Metadata: Update the swarm hash to the current specification, changes bzzr0 to bzzr1 and urls to use bzz-raw://
+      "a265627a7a72315820" <>
+          <<_::binary-size(64)>> <> "64736f6c6343" <> <<_::binary-size(6)>> <> "0032" <> constructor_arguments ->
+        if passed_constructor_arguments == constructor_arguments do
+          true
+        else
+          extract_constructor_arguments(constructor_arguments, passed_constructor_arguments)
+        end
+
       <<>> ->
         passed_constructor_arguments == ""
 
diff --git a/apps/explorer/test/explorer/smart_contract/verifier_test.exs b/apps/explorer/test/explorer/smart_contract/verifier_test.exs
index 9633804c60..fba0622964 100644
--- a/apps/explorer/test/explorer/smart_contract/verifier_test.exs
+++ b/apps/explorer/test/explorer/smart_contract/verifier_test.exs
@@ -56,6 +56,33 @@ defmodule Explorer.SmartContract.VerifierTest do
       assert abi != nil
     end
 
+    test "verifies smart contract with new `whisper` metadata (bzz0 => bzz1) in solidity 0.5.11" do
+      contract_data =
+        "#{File.cwd!()}/test/support/fixture/smart_contract/solidity_5.11_new_whisper_metadata.json"
+        |> File.read!()
+        |> Jason.decode!()
+
+      compiler_version = contract_data["compiler_version"]
+      name = contract_data["name"]
+      optimize = false
+      contract = contract_data["contract"]
+      expected_bytecode = contract_data["bytecode"]
+      evm_version = contract_data["evm_version"]
+
+      contract_address = insert(:contract_address, contract_code: "0x" <> expected_bytecode)
+
+      params = %{
+        "contract_source_code" => contract,
+        "compiler_version" => compiler_version,
+        "evm_version" => evm_version,
+        "name" => name,
+        "optimization" => optimize
+      }
+
+      assert {:ok, %{abi: abi}} = Verifier.evaluate_authenticity(contract_address.hash, params)
+      assert abi != nil
+    end
+
     test "verifies smart contract with constructor arguments", %{
       contract_code_info: contract_code_info
     } do
diff --git a/apps/explorer/test/support/fixture/smart_contract/solidity_5.11_new_whisper_metadata.json b/apps/explorer/test/support/fixture/smart_contract/solidity_5.11_new_whisper_metadata.json
new file mode 100644
index 0000000000..bd0301ef78
--- /dev/null
+++ b/apps/explorer/test/support/fixture/smart_contract/solidity_5.11_new_whisper_metadata.json
@@ -0,0 +1,7 @@
+{
+  "bytecode": "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+  "compiler_version": "v0.5.11+commit.c082d0b4",
+  "contract": "/**\r\n *Submitted for verification at Etherscan.io on 2019-08-16\r\n*/\r\n\r\npragma solidity ^0.5.0;\r\n\r\n\r\n// ----------------------------------------------------------------------------\r\n\r\n// 'FIXED' 'Example Fixed Supply Token' token contract\r\n\r\n//\r\n\r\n// Symbol      : FIXED\r\n\r\n// Name        : Example Fixed Supply Token\r\n\r\n// Total supply: 1,000,000.000000000000000000\r\n\r\n// Decimals    : 18\r\n\r\n//\r\n\r\n// Enjoy.\r\n\r\n//\r\n\r\n// (c) BokkyPooBah / Bok Consulting Pty Ltd 2018. The MIT Licence.\r\n\r\n// ----------------------------------------------------------------------------\r\n\r\n\r\n\r\n// ----------------------------------------------------------------------------\r\n\r\n// Safe maths\r\n\r\n// ----------------------------------------------------------------------------\r\n\r\nlibrary SafeMath {\r\n\r\n    function add(uint a, uint b) internal pure returns (uint c) {\r\n\r\n        c = a + b;\r\n\r\n        require(c >= a);\r\n\r\n    }\r\n\r\n    function sub(uint a, uint b) internal pure returns (uint c) {\r\n\r\n        require(b <= a);\r\n\r\n        c = a - b;\r\n\r\n    }\r\n\r\n    function mul(uint a, uint b) internal pure returns (uint c) {\r\n\r\n        c = a * b;\r\n\r\n        require(a == 0 || c / a == b);\r\n\r\n    }\r\n\r\n    function div(uint a, uint b) internal pure returns (uint c) {\r\n\r\n        require(b > 0);\r\n\r\n        c = a / b;\r\n\r\n    }\r\n\r\n}\r\n\r\n\r\n\r\n// ----------------------------------------------------------------------------\r\n\r\n// ERC Token Standard #20 Interface\r\n\r\n// https://github.com/ethereum/EIPs/blob/master/EIPS/eip-20.md\r\n\r\n// ----------------------------------------------------------------------------\r\n\r\ncontract ERC20Interface {\r\n\r\n    function totalSupply() public view returns (uint);\r\n\r\n    function balanceOf(address tokenOwner) public view returns (uint balance);\r\n\r\n    function allowance(address tokenOwner, address spender) public view returns (uint remaining);\r\n\r\n    function transfer(address to, uint tokens) public returns (bool success);\r\n\r\n    function approve(address spender, uint tokens) public returns (bool success);\r\n\r\n    function transferFrom(address from, address to, uint tokens) public returns (bool success);\r\n\r\n\r\n    event Transfer(address indexed from, address indexed to, uint tokens);\r\n\r\n    event Approval(address indexed tokenOwner, address indexed spender, uint tokens);\r\n\r\n}\r\n\r\n\r\n\r\n// ----------------------------------------------------------------------------\r\n\r\n// Contract function to receive approval and execute function in one call\r\n\r\n//\r\n\r\n// Borrowed from MiniMeToken\r\n\r\n// ----------------------------------------------------------------------------\r\n\r\ncontract ApproveAndCallFallBack {\r\n\r\n    function receiveApproval(address from, uint256 tokens, address token, bytes memory data) public;\r\n\r\n}\r\n\r\n\r\n\r\n// ----------------------------------------------------------------------------\r\n\r\n// Owned contract\r\n\r\n// ----------------------------------------------------------------------------\r\n\r\ncontract Owned {\r\n\r\n    address public owner;\r\n\r\n    address public newOwner;\r\n\r\n\r\n    event OwnershipTransferred(address indexed _from, address indexed _to);\r\n\r\n\r\n    constructor() public {\r\n\r\n        owner = msg.sender;\r\n\r\n    }\r\n\r\n\r\n    modifier onlyOwner {\r\n\r\n        require(msg.sender == owner);\r\n\r\n        _;\r\n\r\n    }\r\n\r\n\r\n    function transferOwnership(address _newOwner) public onlyOwner {\r\n\r\n        newOwner = _newOwner;\r\n\r\n    }\r\n\r\n    function acceptOwnership() public {\r\n\r\n        require(msg.sender == newOwner);\r\n\r\n        emit OwnershipTransferred(owner, newOwner);\r\n\r\n        owner = newOwner;\r\n\r\n        newOwner = address(0);\r\n\r\n    }\r\n\r\n}\r\n\r\n\r\n\r\n// ----------------------------------------------------------------------------\r\n\r\n// ERC20 Token, with the addition of symbol, name and decimals and a\r\n\r\n// fixed supply\r\n\r\n// ----------------------------------------------------------------------------\r\n\r\ncontract FixedSupplyToken is ERC20Interface, Owned {\r\n\r\n    using SafeMath for uint;\r\n\r\n\r\n    string public symbol;\r\n\r\n    string public  name;\r\n\r\n    uint8 public decimals;\r\n\r\n    uint _totalSupply;\r\n\r\n\r\n    mapping(address => uint) balances;\r\n\r\n    mapping(address => mapping(address => uint)) allowed;\r\n\r\n\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    // Constructor\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    constructor() public {\r\n\r\n        symbol = \"TEST\";\r\n\r\n        name = \"Test Token\";\r\n\r\n        decimals = 18;\r\n\r\n        _totalSupply = 1000000 * 10**uint(decimals);\r\n\r\n        balances[owner] = _totalSupply;\r\n\r\n        emit Transfer(address(0), owner, _totalSupply);\r\n\r\n    }\r\n\r\n\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    // Total supply\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    function totalSupply() public view returns (uint) {\r\n\r\n        return _totalSupply.sub(balances[address(0)]);\r\n\r\n    }\r\n\r\n\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    // Get the token balance for account `tokenOwner`\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    function balanceOf(address tokenOwner) public view returns (uint balance) {\r\n\r\n        return balances[tokenOwner];\r\n\r\n    }\r\n\r\n\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    // Transfer the balance from token owner's account to `to` account\r\n\r\n    // - Owner's account must have sufficient balance to transfer\r\n\r\n    // - 0 value transfers are allowed\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    function transfer(address to, uint tokens) public returns (bool success) {\r\n\r\n        balances[msg.sender] = balances[msg.sender].sub(tokens);\r\n\r\n        balances[to] = balances[to].add(tokens);\r\n\r\n        emit Transfer(msg.sender, to, tokens);\r\n\r\n        return true;\r\n\r\n    }\r\n\r\n\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    // Token owner can approve for `spender` to transferFrom(...) `tokens`\r\n\r\n    // from the token owner's account\r\n\r\n    //\r\n\r\n    // https://github.com/ethereum/EIPs/blob/master/EIPS/eip-20-token-standard.md\r\n\r\n    // recommends that there are no checks for the approval double-spend attack\r\n\r\n    // as this should be implemented in user interfaces\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    function approve(address spender, uint tokens) public returns (bool success) {\r\n\r\n        allowed[msg.sender][spender] = tokens;\r\n\r\n        emit Approval(msg.sender, spender, tokens);\r\n\r\n        return true;\r\n\r\n    }\r\n\r\n\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    // Transfer `tokens` from the `from` account to the `to` account\r\n\r\n    //\r\n\r\n    // The calling account must already have sufficient tokens approve(...)-d\r\n\r\n    // for spending from the `from` account and\r\n\r\n    // - From account must have sufficient balance to transfer\r\n\r\n    // - Spender must have sufficient allowance to transfer\r\n\r\n    // - 0 value transfers are allowed\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    function transferFrom(address from, address to, uint tokens) public returns (bool success) {\r\n\r\n        balances[from] = balances[from].sub(tokens);\r\n\r\n        allowed[from][msg.sender] = allowed[from][msg.sender].sub(tokens);\r\n\r\n        balances[to] = balances[to].add(tokens);\r\n\r\n        emit Transfer(from, to, tokens);\r\n\r\n        return true;\r\n\r\n    }\r\n\r\n\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    // Returns the amount of tokens approved by the owner that can be\r\n\r\n    // transferred to the spender's account\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    function allowance(address tokenOwner, address spender) public view returns (uint remaining) {\r\n\r\n        return allowed[tokenOwner][spender];\r\n\r\n    }\r\n\r\n\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    // Token owner can approve for `spender` to transferFrom(...) `tokens`\r\n\r\n    // from the token owner's account. The `spender` contract function\r\n\r\n    // `receiveApproval(...)` is then executed\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    function approveAndCall(address spender, uint tokens, bytes memory data) public returns (bool success) {\r\n\r\n        allowed[msg.sender][spender] = tokens;\r\n\r\n        emit Approval(msg.sender, spender, tokens);\r\n\r\n        ApproveAndCallFallBack(spender).receiveApproval(msg.sender, tokens, address(this), data);\r\n\r\n        return true;\r\n\r\n    }\r\n\r\n\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    // Don't accept ETH\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    function () external payable {\r\n\r\n        revert();\r\n\r\n    }\r\n\r\n\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    // Owner can transfer out any accidentally sent ERC20 tokens\r\n\r\n    // ------------------------------------------------------------------------\r\n\r\n    function transferAnyERC20Token(address tokenAddress, uint tokens) public onlyOwner returns (bool success) {\r\n\r\n        return ERC20Interface(tokenAddress).transfer(owner, tokens);\r\n\r\n    }\r\n\r\n}",
+  "name": "FixedSupplyToken",
+  "evm_version": "byzantium"
+}