rpc: extract sender address from msg signature (#217)

* extract real from address in rpc tx query api

Closes: #210

* Update x/evm/types/msg.go

Co-authored-by: Federico Kunze Küllmer <31522760+fedekunze@users.noreply.github.com>

Co-authored-by: Federico Kunze Küllmer <31522760+fedekunze@users.noreply.github.com>

ethereum/rpc/backend/backend.go

@@ -49,15 +49,21 @@ type EVMBackend struct {
 	clientCtx   client.Context
 	queryClient *types.QueryClient // gRPC query client
 	logger      log.Logger
+	chainID     *big.Int
 }
 
 // NewEVMBackend creates a new EVMBackend instance
 func NewEVMBackend(clientCtx client.Context) *EVMBackend {
+	chainID, err := ethermint.ParseChainID(clientCtx.ChainID)
+	if err != nil {
+		panic(err)
+	}
 	return &EVMBackend{
 		ctx:         context.Background(),
 		clientCtx:   clientCtx,
 		queryClient: types.NewQueryClient(clientCtx),
 		logger:      log.WithField("module", "evm-backend"),
+		chainID:     chainID,
 	}
 }
 
@@ -151,9 +157,13 @@ func (e *EVMBackend) EthBlockFromTendermint(
 
 		hash := msg.AsTransaction().Hash()
 		if fullTx {
+			from, err := msg.GetSender(e.chainID)
+			if err != nil {
+				from = common.HexToAddress(msg.From)
+			}
 			ethTx, err := types.NewTransactionFromData(
 				msg.Data,
-				common.HexToAddress(msg.From),
+				from,
 				hash,
 				common.BytesToHash(block.Hash()),
 				uint64(block.Height),

ethereum/rpc/namespaces/eth/api.go

@@ -723,9 +723,13 @@ func (e *PublicAPI) GetTransactionByHash(hash common.Hash) (*rpctypes.RPCTransac
 		return nil, fmt.Errorf("invalid tx type: %T", tx)
 	}
 
+	from, err := msg.GetSender(e.chainIDEpoch)
+	if err != nil {
+		return nil, err
+	}
 	return rpctypes.NewTransactionFromData(
 		msg.Data,
-		common.HexToAddress(msg.From),
+		from,
 		hash,
 		common.BytesToHash(resBlock.Block.Hash()),
 		uint64(res.Height),
@@ -880,7 +884,10 @@ func (e *PublicAPI) GetTransactionReceipt(hash common.Hash) (map[string]interfac
 		status = hexutil.Uint(ethtypes.ReceiptStatusFailed)
 	}
 
-	from := common.HexToAddress(msg.From)
+	from, err := msg.GetSender(e.chainIDEpoch)
+	if err != nil {
+		return nil, err
+	}
 
 	resLogs, err := e.queryClient.TxLogs(e.ctx, &evmtypes.QueryTxLogsRequest{Hash: hash.Hex()})
 	if err != nil {

x/evm/types/msg.go

@@ -216,3 +216,14 @@ func (msg MsgEthereumTx) AsTransaction() *ethtypes.Transaction {
 func (msg MsgEthereumTx) AsMessage(signer ethtypes.Signer) (core.Message, error) {
 	return msg.AsTransaction().AsMessage(signer)
 }
+
+// GetSender extracts the sender address from the signature values using the latest signer for the given chainID.
+func (msg *MsgEthereumTx) GetSender(chainID *big.Int) (common.Address, error) {
+	signer := ethtypes.LatestSignerForChainID(chainID)
+	from, err := signer.Sender(msg.AsTransaction())
+	if err != nil {
+		return common.Address{}, err
+	}
+	msg.From = from.Hex()
+	return from, nil
+}

x/evm/types/msg_test.go

@@ -183,9 +183,7 @@ func (suite *MsgsTestSuite) TestMsgEthereumTx_Sign() {
 		if tc.expectPass {
 			suite.Require().NoError(err, "valid test %d failed: %s", i, tc.msg)
 
-			tx := tc.tx.AsTransaction()
+			sender, err := tc.tx.GetSender(suite.chainID)
-
-			sender, err := ethtypes.Sender(tc.ethSigner, tx)
 			suite.Require().NoError(err, tc.msg)
 			suite.Require().Equal(tc.tx.From, sender.Hex(), tc.msg)
 		} else {