From 664aac28479c8af22cca5ca7325fa78c2f8f7e9d Mon Sep 17 00:00:00 2001
From: Dmitry <d@kozlov.ru>
Date: Thu, 29 Nov 2018 13:33:41 +0300
Subject: [PATCH] Fixed invalid signature from web3.js

---
 Sources/Convenience/LibSecp256k1Extension.swift | 10 +++++++++-
 Tests/SECP256K1Tests.swift                      | 14 ++++++++++++++
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/Sources/Convenience/LibSecp256k1Extension.swift b/Sources/Convenience/LibSecp256k1Extension.swift
index 4acf514..96f53af 100644
--- a/Sources/Convenience/LibSecp256k1Extension.swift
+++ b/Sources/Convenience/LibSecp256k1Extension.swift
@@ -258,7 +258,15 @@ struct SECP256K1 {
         try signature.checkSignatureSize()
         var recoverableSignature = secp256k1_ecdsa_recoverable_signature()
         let serializedSignature = Data(signature[0 ..< 64])
-        let v = Int32(signature[64])
+        var v = Int32(signature[64])
+        
+        /*
+         fix for web3.js signs
+         eth-lib code: vrs.v < 2 ? vrs.v : 1 - (vrs.v % 2)
+        https://github.com/MaiaVictor/eth-lib/blob/d959c54faa1e1ac8d474028ed1568c5dce27cc7a/src/account.js#L60
+        */
+        v = v < 2 ? v : 1 - (v % 2)
+        
         let result = serializedSignature.withUnsafeBytes { (serPtr: UnsafePointer<UInt8>) -> Int32 in
             withUnsafeMutablePointer(to: &recoverableSignature, { (signaturePointer: UnsafeMutablePointer<secp256k1_ecdsa_recoverable_signature>) in
                 secp256k1_ecdsa_recoverable_signature_parse_compact(context!, signaturePointer, serPtr, v)
diff --git a/Tests/SECP256K1Tests.swift b/Tests/SECP256K1Tests.swift
index 43f7793..12c546a 100644
--- a/Tests/SECP256K1Tests.swift
+++ b/Tests/SECP256K1Tests.swift
@@ -98,4 +98,18 @@ class SECP256K1Tests: XCTestCase {
             }
         }
     }
+
+    func testSomeSignatures() throws {
+        
+        let password = "Your password"
+        let keystore = try! BIP32Keystore(mnemonics: Mnemonics(), password: password)
+        
+        for i in 1...3 {
+            print("Signing \(i)/10")
+            let message = "\(i) Hello World \(i)".data
+            let signature = try! Web3Signer.signPersonalMessage(message, keystore: keystore, account: keystore.addresses[0], password: password)
+            let address = try! Web3.default.personal.ecrecover(personalMessage: message, signature: signature)
+            XCTAssertEqual(address,keystore.addresses[0])
+        }
+    }
 }