From be8fd869ff9197b9c2e4467b5398dc3a3255b531 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Federico=20Kunze=20K=C3=BCllmer?=
 <31522760+fedekunze@users.noreply.github.com>
Date: Mon, 22 Nov 2021 16:39:25 +0100
Subject: [PATCH] rpc: fix default signer (#769)

* rpc: fix default signer

* changelog
---
 CHANGELOG.md                       |  6 ++++++
 rpc/ethereum/namespaces/eth/api.go | 11 ++++++++---
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index c9500c32bd..e1eb6abc1e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -35,6 +35,12 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 # Changelog
 
+## Unreleased
+
+### Bug Fixes
+
+* (rpc) [tharsis#769](https://github.com/tharsis/ethermint/pull/769) Fix default Ethereum signer for JSON-RPC.
+
 ## [v0.8.0] - 2021-11-17
 
 ### State Machine Breaking
diff --git a/rpc/ethereum/namespaces/eth/api.go b/rpc/ethereum/namespaces/eth/api.go
index d52ea534c3..d46b4edcd4 100644
--- a/rpc/ethereum/namespaces/eth/api.go
+++ b/rpc/ethereum/namespaces/eth/api.go
@@ -56,7 +56,7 @@ func NewPublicAPI(
 	backend backend.Backend,
 	nonceLock *rpctypes.AddrLocker,
 ) *PublicAPI {
-	epoch, err := ethermint.ParseChainID(clientCtx.ChainID)
+	eip155ChainID, err := ethermint.ParseChainID(clientCtx.ChainID)
 	if err != nil {
 		panic(err)
 	}
@@ -80,13 +80,18 @@ func NewPublicAPI(
 
 	// The signer used by the API should always be the 'latest' known one because we expect
 	// signers to be backwards-compatible with old transactions.
-	signer := ethtypes.LatestSigner(backend.ChainConfig())
+	cfg := backend.ChainConfig()
+	if cfg == nil {
+		cfg = evmtypes.DefaultChainConfig().EthereumConfig(eip155ChainID)
+	}
+
+	signer := ethtypes.LatestSigner(cfg)
 
 	api := &PublicAPI{
 		ctx:          context.Background(),
 		clientCtx:    clientCtx,
 		queryClient:  rpctypes.NewQueryClient(clientCtx),
-		chainIDEpoch: epoch,
+		chainIDEpoch: eip155ChainID,
 		logger:       logger.With("client", "json-rpc"),
 		backend:      backend,
 		nonceLock:    nonceLock,