From 493dabe8ce8176b5c7cb278fe99ed235a5758c7e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Kripalani?= <raul@protocol.ai>
Date: Sat, 11 Feb 2023 14:16:50 +0000
Subject: [PATCH] delegated signature: allow it to carry MethodSend before
 nv20.

---
 chain/consensus/filcns/filecoin.go       | 2 +-
 chain/messagepool/messagepool.go         | 7 ++++++-
 chain/signatures.go                      | 6 +++++-
 chain/types/ethtypes/eth_transactions.go | 8 +++++++-
 node/impl/full/eth.go                    | 7 +++++++
 5 files changed, 26 insertions(+), 4 deletions(-)

diff --git a/chain/consensus/filcns/filecoin.go b/chain/consensus/filcns/filecoin.go
index 2cd680746..7f94e4806 100644
--- a/chain/consensus/filcns/filecoin.go
+++ b/chain/consensus/filcns/filecoin.go
@@ -592,7 +592,7 @@ func (filec *FilecoinEC) checkBlockMessages(ctx context.Context, b *types.FullBl
 			return xerrors.Errorf("failed to resolve key addr: %w", err)
 		}
 
-		if err := chain.AuthenticateMessage(m, kaddr); err != nil {
+		if err := chain.AuthenticateMessage(m, kaddr, nv); err != nil {
 			return xerrors.Errorf("failed to validate signature: %w", err)
 		}
 
diff --git a/chain/messagepool/messagepool.go b/chain/messagepool/messagepool.go
index dabd2cb33..e30d8c5e3 100644
--- a/chain/messagepool/messagepool.go
+++ b/chain/messagepool/messagepool.go
@@ -794,7 +794,12 @@ func (mp *MessagePool) VerifyMsgSig(m *types.SignedMessage) error {
 		return nil
 	}
 
-	if err := chain.AuthenticateMessage(m, m.Message.From); err != nil {
+	nv, err := mp.getNtwkVersion(mp.curTs.Height())
+	if err != nil {
+		return xerrors.Errorf("failedl to get network version: %w", err)
+	}
+	
+	if err := chain.AuthenticateMessage(m, m.Message.From, nv); err != nil {
 		return xerrors.Errorf("failed to validate signature: %w", err)
 	}
 
diff --git a/chain/signatures.go b/chain/signatures.go
index 1dc67fd2c..0074bc42f 100644
--- a/chain/signatures.go
+++ b/chain/signatures.go
@@ -1,6 +1,7 @@
 package chain
 
 import (
+	"github.com/filecoin-project/go-state-types/builtin"
 	"golang.org/x/xerrors"
 
 	"github.com/filecoin-project/go-address"
@@ -16,12 +17,15 @@ import (
 // SignedMessage was signed by the indicated Address, computing the correct
 // signature payload depending on the signature type. The supplied Address type
 // must be recognized by the registered verifier for the signature type.
-func AuthenticateMessage(msg *types.SignedMessage, signer address.Address) error {
+func AuthenticateMessage(msg *types.SignedMessage, signer address.Address, nv network.Version) error {
 	var digest []byte
 
 	typ := msg.Signature.Type
 	switch typ {
 	case crypto.SigTypeDelegated:
+		if msg.Message.Method == builtin.MethodSend && nv >= network.Version20 {
+			return xerrors.Errorf("nv20 and above no longer admits method 0 on messages with Ethereum delegated signatures")
+		}
 		txArgs, err := ethtypes.EthTxArgsFromUnsignedEthMessage(&msg.Message)
 		if err != nil {
 			return xerrors.Errorf("failed to reconstruct eth transaction: %w", err)
diff --git a/chain/types/ethtypes/eth_transactions.go b/chain/types/ethtypes/eth_transactions.go
index 7c065928e..4f350c4ca 100644
--- a/chain/types/ethtypes/eth_transactions.go
+++ b/chain/types/ethtypes/eth_transactions.go
@@ -117,7 +117,13 @@ func EthTxArgsFromUnsignedEthMessage(msg *types.Message) (EthTxArgs, error) {
 		default:
 			return EthTxArgs{}, fmt.Errorf("unsupported EAM method")
 		}
-	} else if msg.Method == builtintypes.MethodsEVM.InvokeContract {
+	} else if msg.Method == builtintypes.MethodsEVM.InvokeContract || msg.Method == builtintypes.MethodSend {
+		// < nv20 (Hyperspace): The condition here is technically too lenient.
+		// The correct behavior would be to _only_ allow MethodSend on < nv20.
+		// However, snaking through the network version here is too expensive, and not worth it,
+		// given that the transition period will only last for ~24h anyway.
+		// AuthenticateMessage is the _crucial_ spot, and it's already applying a stricter check.
+		// The Eth API endpoint is also selecting the right method depending on the network version.
 		addr, err := EthAddressFromFilecoinAddress(msg.To)
 		if err != nil {
 			return EthTxArgs{}, err
diff --git a/node/impl/full/eth.go b/node/impl/full/eth.go
index 8401d7d51..6122143f8 100644
--- a/node/impl/full/eth.go
+++ b/node/impl/full/eth.go
@@ -10,6 +10,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/filecoin-project/go-state-types/network"
 	"github.com/google/uuid"
 	"github.com/ipfs/go-cid"
 	cbg "github.com/whyrusleeping/cbor-gen"
@@ -768,6 +769,12 @@ func (a *EthModule) ethCallToFilecoinMessage(ctx context.Context, tx ethtypes.Et
 		}
 
 		method = builtintypes.MethodsEVM.InvokeContract
+
+		// < nv20 (Hyperspace): reset method to MethodSend if no params.
+		nv := a.StateManager.GetNetworkVersion(ctx, a.Chain.GetHeaviestTipSet().Height())
+		if nv < network.Version20 && len(tx.Data) == 0 {
+			method = builtintypes.MethodSend
+		}
 	}
 
 	return &types.Message{