From c89701016ae3b28f8d6e1099ac32cff5155722c9 Mon Sep 17 00:00:00 2001
From: Mark Spanbroek <mark@spanbroek.net>
Date: Mon, 3 Jul 2023 15:51:42 +0200
Subject: [PATCH] Fix EIP-155 signatures

---
 ethers/wallet.nim         |  7 +++++--
 testmodule/testWallet.nim | 36 +++++++++++++-----------------------
 2 files changed, 18 insertions(+), 25 deletions(-)

diff --git a/ethers/wallet.nim b/ethers/wallet.nim
index 32dc65a..3687b35 100644
--- a/ethers/wallet.nim
+++ b/ethers/wallet.nim
@@ -58,6 +58,10 @@ method getAddress(wallet: Wallet): Future[Address] {.async.} =
   return wallet.address
 
 proc signTransaction(tr: var SignableTransaction, pk: PrivateKey) =
+  # Temporary V value, used to signal to the hashing function the
+  # chain id that we'd like to use for an EIP-155 signature
+  tr.V = int64(uint64(tr.chainId)) * 2 + 35
+
   let h = tr.txHashNoSignature
   let s = sign(pk, SkMessage(h.data))
 
@@ -69,8 +73,7 @@ proc signTransaction(tr: var SignableTransaction, pk: PrivateKey) =
 
   case tr.txType:
   of TxLegacy:
-    #tr.V = int64(v) + int64(tr.chainId)*2 + 35  #TODO does not work, not sure why. Sending the tx results in error of too little funds. Maybe something wrong with signature and a wrong sender gets encoded?
-    tr.V = int64(v) + 27
+    tr.V = int64(v) + int64(uint64(tr.chainId))*2 + 35
   of TxEip1559:
     tr.V = int64(v)
   else:
diff --git a/testmodule/testWallet.nim b/testmodule/testWallet.nim
index 14f4c73..366a489 100644
--- a/testmodule/testWallet.nim
+++ b/testmodule/testWallet.nim
@@ -56,29 +56,19 @@ suite "Wallet":
     check $wallet.address == "0x328809bc894f92807417d2dad6b7c998c1afdac6"
 
   test "Can sign manually created transaction":
-    let wallet = Wallet.new(pk1)
-    let tx = Transaction(
-      to: wallet.address,
-      nonce: some 0.u256,
-      chainId: some 31337.u256,
-      gasPrice: some 1_000_000_000.u256,
-      gasLimit: some 21_000.u256,
+    # Example from EIP-155
+    let wallet = Wallet.new("0x4646464646464646464646464646464646464646464646464646464646464646")
+    let transaction = Transaction(
+      to: !Address.init("0x3535353535353535353535353535353535353535"),
+      nonce: some 9.u256,
+      chainId: some 1.u256,
+      gasPrice: some 20 * 10.u256.pow(9),
+      gasLimit: some 21000.u256,
+      value: 10.u256.pow(18),
+      data: @[]
     )
-    let signedTx = await wallet.signTransaction(tx)
-    check signedTx.toHex == "f86380843b9aca0082520894328809bc894f92807417d2dad6b7c998c1afdac680801ba04ae9b24cba72103bb30a1e91c016796fc2bf2d46d2b75ca80211fae0337c3c03a05e3c81ce9944a07f18b65142a1847c5b72f993c8e7c28d5d4360ff36a2fed049"
-
-  test "Can sign manually created contract call":
-    let wallet = Wallet.new(pk1)
-    let tx = Transaction(
-      to: wallet.address,
-      data: @[24.byte, 22, 13, 221], # Arbitrary Calldata for totalsupply()
-      nonce: some 0.u256,
-      chainId: some 31337.u256,
-      gasPrice: some 1_000_000_000.u256,
-      gasLimit: some 21_000.u256,
-    )
-    let signedTx = await wallet.signTransaction(tx)
-    check signedTx.toHex == "f86780843b9aca0082520894328809bc894f92807417d2dad6b7c998c1afdac6808418160ddd1ca029261fc74ffbbb5ce3d0a3b6eac9726f05d8a849e0f1535722e057bdd83b9659a044f857852bd8b7bb8c0c0a5a61c2c56fce42edacab73f42301b509edb7600ff1"
+    let signed = await wallet.signTransaction(transaction)
+    check signed.toHex == "f86c098504a817c800825208943535353535353535353535353535353535353535880de0b6b3a76400008025a028ef61340bd939bc2195fe537567866003e1a15d3c71ff63e1590620aa636276a067cbe9d8997f761aecb703304b3800ccf555c9f3dc64214b297fb1966a3b6d83"
 
   test "Can sign manually created tx with EIP1559":
     let wallet = Wallet.new(pk1)
@@ -104,7 +94,7 @@ suite "Wallet":
     )
     let signedTx = await wallet.signTransaction(tx)
     let txHash = await provider.sendTransaction(signedTx)
-    check txHash.hash == TransactionHash([167.byte, 105, 79, 222, 144, 123, 214, 138, 4, 199, 124, 181, 35, 236, 79, 93, 84, 4, 85, 172, 40, 50, 189, 187, 219, 6, 172, 98, 243, 196, 93, 64])
+    check txHash.hash != TransactionHash.default
 
   test "Can call state-changing function automatically":
     #TODO add actual token contract, not random address. Should work regardless