From ba1c0f0639e563a486e37b6ef40702f6a9f1f8b9 Mon Sep 17 00:00:00 2001
From: Fridrik Asmundsson <fridrik01@gmail.com>
Date: Tue, 6 Jun 2023 17:17:15 -0500
Subject: [PATCH] Add new lotus-shed command for computing eth hash for a given
 message cid

---
 cmd/lotus-shed/eth.go | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/cmd/lotus-shed/eth.go b/cmd/lotus-shed/eth.go
index 1ebe2fb59aa..fde4f96f68f 100644
--- a/cmd/lotus-shed/eth.go
+++ b/cmd/lotus-shed/eth.go
@@ -9,6 +9,7 @@ import (
 	"github.com/filecoin-project/go-state-types/abi"
 
 	"github.com/filecoin-project/lotus/chain/types"
+	"github.com/filecoin-project/lotus/chain/types/ethtypes"
 	lcli "github.com/filecoin-project/lotus/cli"
 )
 
@@ -23,6 +24,7 @@ var ethCmd = &cli.Command{
 	},
 	Subcommands: []*cli.Command{
 		checkTipsetsCmd,
+		computeEthHashCmd,
 	},
 }
 
@@ -70,3 +72,36 @@ var checkTipsetsCmd = &cli.Command{
 		return nil
 	},
 }
+
+var computeEthHashCmd = &cli.Command{
+	Name:  "compute-eth-hash",
+	Usage: "Compute the eth hash for a given message CID",
+	Action: func(cctx *cli.Context) error {
+		if cctx.NArg() != 1 {
+			return lcli.IncorrectNumArgs(cctx)
+		}
+
+		msg, err := messageFromString(cctx, cctx.Args().First())
+		if err != nil {
+			return err
+		}
+
+		switch msg := msg.(type) {
+		case *types.SignedMessage:
+			tx, err := ethtypes.EthTxFromSignedEthMessage(msg)
+			if err != nil {
+				return fmt.Errorf("failed to convert from signed message: %w", err)
+			}
+
+			tx.Hash, err = tx.TxHash()
+			if err != nil {
+				return fmt.Errorf("failed to call TxHash: %w", err)
+			}
+			fmt.Println(tx.Hash)
+		default:
+			return fmt.Errorf("not a signed message")
+		}
+
+		return nil
+	},
+}