From 3060994b7264998050145d2ae87f2f843262a776 Mon Sep 17 00:00:00 2001
From: Alex <alex.luu@mail.utoronto.ca>
Date: Thu, 28 Sep 2023 14:03:15 -0400
Subject: [PATCH] 6344 - normalize v on recover  (#6462)

* recover function accepts both v < 27 and v>= 27

* update changelog

* update linter
---
 packages/web3-eth-accounts/CHANGELOG.md              | 6 +++++-
 packages/web3-eth-accounts/src/account.ts            | 7 +++++--
 packages/web3-eth-accounts/test/fixtures/account.ts  | 5 +++++
 packages/web3-eth-accounts/test/unit/account.test.ts | 7 +++++++
 4 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/packages/web3-eth-accounts/CHANGELOG.md b/packages/web3-eth-accounts/CHANGELOG.md
index 9c11ba18dd4..1c3a8291f2e 100644
--- a/packages/web3-eth-accounts/CHANGELOG.md
+++ b/packages/web3-eth-accounts/CHANGELOG.md
@@ -137,4 +137,8 @@ Documentation:
 -   Fixed "The `r` and `s` returned by `sign` to does not always consist of 64 characters" (#6411)
 
 
-## [Unreleased]
\ No newline at end of file
+## [Unreleased]
+
+### Fixed
+
+-   Fixed `recover` function, `v` will be normalized to value 0,1 (#6344) 
\ No newline at end of file
diff --git a/packages/web3-eth-accounts/src/account.ts b/packages/web3-eth-accounts/src/account.ts
index 4a3deec6dd5..bb07577cd52 100644
--- a/packages/web3-eth-accounts/src/account.ts
+++ b/packages/web3-eth-accounts/src/account.ts
@@ -341,10 +341,13 @@ export const recover = (
 	const V_INDEX = 130; // r = first 32 bytes, s = second 32 bytes, v = last byte of signature
 	const hashedMessage = prefixedOrR ? data : hashMessage(data);
 
-	const v = signatureOrV.substring(V_INDEX); // 0x + r + s + v
+	let v = parseInt(signatureOrV.substring(V_INDEX),16); // 0x + r + s + v
+	if (v > 26) {
+		v -= 27;
+	}
 
 	const ecPublicKey = secp256k1.Signature.fromCompact(signatureOrV.slice(2, V_INDEX))
-		.addRecoveryBit(parseInt(v, 16) - 27)
+		.addRecoveryBit(v)
 		.recoverPublicKey(hashedMessage.replace('0x', ''))
 		.toRawBytes(false);
 
diff --git a/packages/web3-eth-accounts/test/fixtures/account.ts b/packages/web3-eth-accounts/test/fixtures/account.ts
index 4638b6e2717..6e64595c28b 100644
--- a/packages/web3-eth-accounts/test/fixtures/account.ts
+++ b/packages/web3-eth-accounts/test/fixtures/account.ts
@@ -381,6 +381,11 @@ export const invalidEncryptData: [
 	],
 ];
 
+export const validRecover: [string, string][] = [
+	[ "I hereby confirm that I am the sole beneficial owner of the assets involved in the business relationship with Fiat24. \nI hereby undertake to inform Fiat24 proactively of any changes to the information contained herein.", "0xec4f73260ac14882e65995a09359896a0ae8f16bd0d28b0d9171655b4e85271e07cda040be059fdcbf52709e3c993eb50a89ce33f41617dc090dc80a583e3c4f00",], // v < 27
+	["test", "0xefb42c22baa0143b322e93b24b0903a0ef47a64b716fbb77debbea55a93dec3e4417aff7dce845723240916c6e34cf17c674828b3addfb0afad966334df5b6311b"] // v >= 27
+]
+
 export const invalidKeyStore: [[any, string]][] = [
 	[
 		// invalid keystore error, missing id field
diff --git a/packages/web3-eth-accounts/test/unit/account.test.ts b/packages/web3-eth-accounts/test/unit/account.test.ts
index b2614137a0d..1f61b74c5f7 100644
--- a/packages/web3-eth-accounts/test/unit/account.test.ts
+++ b/packages/web3-eth-accounts/test/unit/account.test.ts
@@ -42,6 +42,7 @@ import {
 	validHashMessageData,
 	validPrivateKeytoAccountData,
 	validPrivateKeyToAddressData,
+	validRecover,
 } from '../fixtures/account';
 import { TransactionFactory } from '../../src/tx/transactionFactory';
 import { TxData } from '../../src/tx/types';
@@ -215,5 +216,11 @@ describe('accounts', () => {
 				await expect(result).rejects.toThrow(Web3ValidatorError);
 			});
 		});
+
+		describe('valid signatures for recover', () => {
+			it.each(validRecover)('&s', (data, signature) => {
+				recover(data, signature)
+			})
+		})
 	});
 });