From 78387523524ce8719993e33b5b980e41a8a4eb59 Mon Sep 17 00:00:00 2001
From: Aayush Rajasekaran <arajasek94@gmail.com>
Date: Tue, 17 Nov 2020 01:34:06 -0500
Subject: [PATCH] Avoid sending messages to the zero BLS address

---
 build/params_shared_funcs.go     | 9 +++++++++
 build/params_shared_vals.go      | 3 +++
 build/params_testground.go       | 3 ++-
 chain/messagepool/messagepool.go | 4 ++--
 chain/sync.go                    | 2 +-
 chain/types/message.go           | 8 +++++++-
 6 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/build/params_shared_funcs.go b/build/params_shared_funcs.go
index 77fd9256d44..bcd82bb4821 100644
--- a/build/params_shared_funcs.go
+++ b/build/params_shared_funcs.go
@@ -19,3 +19,12 @@ func DhtProtocolName(netName dtypes.NetworkName) protocol.ID {
 func SetAddressNetwork(n address.Network) {
 	address.CurrentNetwork = n
 }
+
+func MustParseAddress(addr string) address.Address {
+	ret, err := address.NewFromString(addr)
+	if err != nil {
+		panic(err)
+	}
+
+	return ret
+}
diff --git a/build/params_shared_vals.go b/build/params_shared_vals.go
index 5070777bd6f..c84f558bfb1 100644
--- a/build/params_shared_vals.go
+++ b/build/params_shared_vals.go
@@ -61,6 +61,9 @@ const TicketRandomnessLookback = abi.ChainEpoch(1)
 
 const AddressMainnetEnvVar = "_mainnet_"
 
+// the 'f' prefix doesn't matter
+var ZeroAddress = MustParseAddress("f3yaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaby2smx7a")
+
 // /////
 // Devnet settings
 
diff --git a/build/params_testground.go b/build/params_testground.go
index 6a8e2abf321..eb3df1cd1e2 100644
--- a/build/params_testground.go
+++ b/build/params_testground.go
@@ -97,7 +97,8 @@ var (
 	NewestNetworkVersion       = network.Version5
 	ActorUpgradeNetworkVersion = network.Version4
 
-	Devnet = true
+	Devnet      = true
+	ZeroAddress = MustParseAddress("f3yaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaby2smx7a")
 )
 
 const BootstrapPeerThreshold = 1
diff --git a/chain/messagepool/messagepool.go b/chain/messagepool/messagepool.go
index d9a92073a17..a507b60cfd6 100644
--- a/chain/messagepool/messagepool.go
+++ b/chain/messagepool/messagepool.go
@@ -465,7 +465,7 @@ func (mp *MessagePool) verifyMsgBeforeAdd(m *types.SignedMessage, curTs *types.T
 	epoch := curTs.Height()
 	minGas := vm.PricelistByEpoch(epoch).OnChainMessage(m.ChainLength())
 
-	if err := m.VMMessage().ValidForBlockInclusion(minGas.Total()); err != nil {
+	if err := m.VMMessage().ValidForBlockInclusion(minGas.Total(), build.NewestNetworkVersion); err != nil {
 		return false, xerrors.Errorf("message will not be included in a block: %w", err)
 	}
 
@@ -546,7 +546,7 @@ func (mp *MessagePool) checkMessage(m *types.SignedMessage) error {
 	}
 
 	// Perform syntactic validation, minGas=0 as we check the actual mingas before we add it
-	if err := m.Message.ValidForBlockInclusion(0); err != nil {
+	if err := m.Message.ValidForBlockInclusion(0, build.NewestNetworkVersion); err != nil {
 		return xerrors.Errorf("message not valid for block inclusion: %w", err)
 	}
 
diff --git a/chain/sync.go b/chain/sync.go
index fabf8f37964..d5c6f73fd46 100644
--- a/chain/sync.go
+++ b/chain/sync.go
@@ -1075,7 +1075,7 @@ func (syncer *Syncer) checkBlockMessages(ctx context.Context, b *types.FullBlock
 
 		// Phase 1: syntactic validation, as defined in the spec
 		minGas := pl.OnChainMessage(msg.ChainLength())
-		if err := m.ValidForBlockInclusion(minGas.Total()); err != nil {
+		if err := m.ValidForBlockInclusion(minGas.Total(), syncer.sm.GetNtwkVersion(ctx, b.Header.Height)); err != nil {
 			return err
 		}
 
diff --git a/chain/types/message.go b/chain/types/message.go
index c53ecc7c160..4f6bb78224b 100644
--- a/chain/types/message.go
+++ b/chain/types/message.go
@@ -5,6 +5,8 @@ import (
 	"encoding/json"
 	"fmt"
 
+	"github.com/filecoin-project/go-state-types/network"
+
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/big"
 	"github.com/filecoin-project/lotus/build"
@@ -144,7 +146,7 @@ func (m *Message) EqualCall(o *Message) bool {
 	return (&m1).Equals(&m2)
 }
 
-func (m *Message) ValidForBlockInclusion(minGas int64) error {
+func (m *Message) ValidForBlockInclusion(minGas int64, version network.Version) error {
 	if m.Version != 0 {
 		return xerrors.New("'Version' unsupported")
 	}
@@ -153,6 +155,10 @@ func (m *Message) ValidForBlockInclusion(minGas int64) error {
 		return xerrors.New("'To' address cannot be empty")
 	}
 
+	if m.To == build.ZeroAddress && version >= network.Version7 {
+		return xerrors.New("invalid 'To' address")
+	}
+
 	if m.From == address.Undef {
 		return xerrors.New("'From' address cannot be empty")
 	}