From e2f81236375fa86c4fdb415f5b0954cd1cdf5cd3 Mon Sep 17 00:00:00 2001
From: David Murdoch <187813+davidmurdoch@users.noreply.github.com>
Date: Fri, 15 Sep 2023 16:22:31 -0400
Subject: [PATCH] fix eth_sign

---
 packages/ethereum/ethereum/src/api.ts           |  2 +-
 .../ethereum/tests/api/eth/sign.test.ts         | 17 ++++++++++++++++-
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/packages/ethereum/ethereum/src/api.ts b/packages/ethereum/ethereum/src/api.ts
index 93d5674e8a..c4289b6825 100644
--- a/packages/ethereum/ethereum/src/api.ts
+++ b/packages/ethereum/ethereum/src/api.ts
@@ -2079,7 +2079,7 @@ export default class EthereumApi implements Api {
 
     const messageHash = hashPersonalMessage(Data.toBuffer(message));
     const { v, r, s } = ecsign(messageHash, privateKey.toBuffer());
-    return toRpcSig(v, r, s);
+    return toRpcSig(v + 27n, r, s);
   }
 
   /**
diff --git a/packages/ethereum/ethereum/tests/api/eth/sign.test.ts b/packages/ethereum/ethereum/tests/api/eth/sign.test.ts
index ecfab32d06..f57726ba4e 100644
--- a/packages/ethereum/ethereum/tests/api/eth/sign.test.ts
+++ b/packages/ethereum/ethereum/tests/api/eth/sign.test.ts
@@ -8,6 +8,7 @@ import {
 } from "@ethereumjs/util";
 import getProvider from "../../helpers/getProvider";
 import { Data, Quantity } from "@ganache/utils";
+import { sign } from "crypto";
 
 describe("api", () => {
   describe("eth", () => {
@@ -37,10 +38,17 @@ describe("api", () => {
         const msgHash = hashPersonalMessage(msg);
 
         const address = accounts[0];
-        let sgn = await provider.send("eth_sign", [
+        let sgn: string = await provider.send("eth_sign", [
           address,
           Data.toString(msg)
         ]);
+
+        assert.strictEqual(
+          sgn.substring(sgn.length - 2),
+          "1c", // 28 in hex
+          "eth_sign should produce a v value of 27 or 28"
+        );
+
         const { v, r, s } = fromRpcSig(sgn);
 
         const pub = ecrecover(msgHash, v, r, s);
@@ -59,7 +67,14 @@ describe("api", () => {
 
         let sgn = await provider.send("eth_sign", [accounts[0], msgHex]);
 
+        assert.strictEqual(
+          sgn.substring(sgn.length - 2),
+          "1c", // 28 in hex
+          "eth_sign should produce a v value of 27 or 28"
+        );
+
         const { v, r, s } = fromRpcSig(sgn);
+
         const pub = ecrecover(msgHash, v, r, s);
         const addr = fromSigned(pubToAddress(pub));
         const strAddr = Data.toString(Quantity.toBuffer(addr), 20);