Merge pull request #7952 from blockscout/np-sourcify-constructor-args

Add parsing constructor arguments for sourcify contracts

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 ### Features
 
+- [#7952](https://github.com/blockscout/blockscout/pull/7952) - Add parsing constructor arguments for sourcify contracts
 - [#6190](https://github.com/blockscout/blockscout/pull/6190) - Add EIP-1559 support to gas price oracle
 - [#7977](https://github.com/blockscout/blockscout/pull/7977) - GraphQL: extend schema with new field for existing objects
 

apps/block_scout_web/lib/block_scout_web/templates/address_contract/index.html.eex

@@ -43,7 +43,7 @@
       <% end %>
       <%= if smart_contract_verified || (!smart_contract_verified && metadata_for_verification) do %>
         <% target_contract = if smart_contract_verified, do: @address.smart_contract, else: metadata_for_verification %>
-        <%= if @address.smart_contract.partially_verified && smart_contract_verified do %>
+        <%= if @address.smart_contract.verified_via_sourcify && @address.smart_contract.partially_verified && smart_contract_verified do %>
           <div class="mb-4">
             <i style="color: #f7b32b;" class="fa fa-info-circle"></i><span> <%= gettext("This contract has been partially verified via Sourcify.") %>
         <% else %>

apps/explorer/lib/explorer/chain.ex

@@ -98,6 +98,7 @@ defmodule Explorer.Chain do
   alias Explorer.Market.MarketHistoryCache
   alias Explorer.{PagingOptions, Repo}
   alias Explorer.SmartContract.Helper
+  alias Explorer.SmartContract.Solidity.Verifier
   alias Explorer.Tags.{AddressTag, AddressToTag}
 
   alias Dataloader.Ecto, as: DataloaderEcto
@@ -1913,7 +1914,7 @@ defmodule Explorer.Chain do
           if smart_contract do
             CheckBytecodeMatchingOnDemand.trigger_check(address_result, smart_contract)
             LookUpSmartContractSourcesOnDemand.trigger_fetch(address_result, smart_contract)
-            address_result
+            check_and_update_constructor_args(address_result)
           else
             LookUpSmartContractSourcesOnDemand.trigger_fetch(address_result, nil)
 
@@ -1936,6 +1937,36 @@ defmodule Explorer.Chain do
     end
   end
 
+  defp check_and_update_constructor_args(
+         %SmartContract{address_hash: address_hash, constructor_arguments: nil, verified_via_sourcify: true} =
+           smart_contract
+       ) do
+    if args = Verifier.parse_constructor_arguments_for_sourcify_contract(address_hash, smart_contract.abi) do
+      smart_contract |> SmartContract.changeset(%{constructor_arguments: args}) |> Repo.update()
+      %SmartContract{smart_contract | constructor_arguments: args}
+    else
+      smart_contract
+    end
+  end
+
+  defp check_and_update_constructor_args(
+         %Address{
+           hash: address_hash,
+           contract_code: deployed_bytecode,
+           smart_contract: %SmartContract{constructor_arguments: nil, verified_via_sourcify: true} = smart_contract
+         } = address
+       ) do
+    if args =
+         Verifier.parse_constructor_arguments_for_sourcify_contract(address_hash, smart_contract.abi, deployed_bytecode) do
+      smart_contract |> SmartContract.changeset(%{constructor_arguments: args}) |> Repo.update()
+      %Address{address | smart_contract: %SmartContract{smart_contract | constructor_arguments: args}}
+    else
+      address
+    end
+  end
+
+  defp check_and_update_constructor_args(other), do: other
+
   defp add_twin_info_to_contract(address_result, address_verified_twin_contract, _hash)
        when is_nil(address_verified_twin_contract),
        do: address_result
@@ -4310,7 +4341,7 @@ defmodule Explorer.Chain do
       verified_contract_twin_additional_sources = get_contract_additional_sources(verified_contract_twin, options)
 
       %{
-        :verified_contract => verified_contract_twin,
+        :verified_contract => check_and_update_constructor_args(verified_contract_twin),
         :additional_sources => verified_contract_twin_additional_sources
       }
     else

apps/explorer/lib/explorer/smart_contract/solidity/verifier.ex

@@ -11,8 +11,10 @@ defmodule Explorer.SmartContract.Solidity.Verifier do
   import Explorer.SmartContract.Helper,
     only: [cast_libraries: 1, prepare_bytecode_for_microservice: 3, contract_creation_input: 1]
 
+  # import  Explorer.Chain.SmartContract, only: [:function_description]
   alias ABI.{FunctionSelector, TypeDecoder}
   alias Explorer.Chain
+  alias Explorer.Chain.{Data, Hash, SmartContract}
   alias Explorer.SmartContract.RustVerifierInterface
   alias Explorer.SmartContract.Solidity.CodeCompiler
 
@@ -533,4 +535,53 @@ defmodule Explorer.SmartContract.Solidity.Verifier do
   def parse_boolean(false), do: false
 
   def parse_boolean(_), do: false
+
+  @doc """
+    Function tries to parse constructor args from smart contract creation input.
+      1. using `extract_meta_from_deployed_bytecode/1` we derive CBOR metadata string
+      2. using metadata we split creation_tx_input and try to decode resulting constructor arguments
+       2.1. if we successfully decoded args using constructor's abi, then return constructor args
+       2.2 otherwise return nil
+  """
+  @spec parse_constructor_arguments_for_sourcify_contract(Hash.Address.t(), SmartContract.abi()) :: nil | binary
+  def parse_constructor_arguments_for_sourcify_contract(address_hash, abi) do
+    parse_constructor_arguments_for_sourcify_contract(address_hash, abi, Chain.smart_contract_bytecode(address_hash))
+  end
+
+  @doc """
+    Clause for cases when we already can pass deployed bytecode to this function (in order to avoid excessive read DB accesses)
+  """
+  @spec parse_constructor_arguments_for_sourcify_contract(
+          Hash.Address.t(),
+          SmartContract.abi(),
+          binary | Explorer.Chain.Data.t()
+        ) :: nil | binary
+  def parse_constructor_arguments_for_sourcify_contract(address_hash, abi, deployed_bytecode)
+      when is_binary(deployed_bytecode) do
+    creation_tx_input =
+      case Chain.smart_contract_creation_tx_bytecode(address_hash) do
+        %{init: init, created_contract_code: _created_contract_code} ->
+          "0x" <> init_without_0x = init
+          init_without_0x
+
+        _ ->
+          nil
+      end
+
+    with true <- has_constructor_with_params?(abi),
+         check_function <- parse_constructor_and_return_check_function(abi),
+         false <- is_nil(creation_tx_input) || deployed_bytecode == "0x",
+         {meta, meta_length} <- extract_meta_from_deployed_bytecode(deployed_bytecode),
+         [_bytecode, constructor_args] <- String.split(creation_tx_input, meta <> meta_length),
+         ^constructor_args <- check_function.(constructor_args) do
+      constructor_args
+    else
+      _ ->
+        nil
+    end
+  end
+
+  def parse_constructor_arguments_for_sourcify_contract(address_hash, abi, deployed_bytecode) do
+    parse_constructor_arguments_for_sourcify_contract(address_hash, abi, Data.to_string(deployed_bytecode))
+  end
 end

apps/explorer/test/explorer/chain/csv_export/address_log_csv_exporter_test.exs

@@ -1,6 +1,7 @@
 defmodule Explorer.Chain.AddressLogCsvExporterTest do
   use Explorer.DataCase
 
+  alias Explorer.Chain.Address
   alias Explorer.Chain.CSVExport.AddressLogCsvExporter
 
   describe "export/3" do
@@ -74,7 +75,7 @@ defmodule Explorer.Chain.AddressLogCsvExporterTest do
       assert result.index == to_string(log.index)
       assert result.block_number == to_string(log.block_number)
       assert result.block_hash == to_string(log.block_hash)
-      assert result.address == String.downcase(to_string(log.address))
+      assert result.address == Address.checksum(log.address.hash)
       assert result.data == to_string(log.data)
       assert result.first_topic == to_string(log.first_topic)
       assert result.second_topic == to_string(log.second_topic)