Fix Status Messages During Genesis (#6046)

* fix status messages * fix finalized checkpoint * remove code * Merge refs/heads/master into fixStatusMessages * Update beacon-chain/blockchain/service.go * Merge refs/heads/master into fixStatusMessages * Merge refs/heads/master into fixStatusMessages * Merge refs/heads/master into fixStatusMessages * fix * fix test * fix again * fix * Merge refs/heads/master into fixStatusMessages * Merge refs/heads/master into fixStatusMessages * Merge refs/heads/master into fixStatusMessages * Merge refs/heads/master into fixStatusMessages * Merge refs/heads/master into fixStatusMessages * Merge refs/heads/master into fixStatusMessages * Merge refs/heads/master into fixStatusMessages * Merge refs/heads/master into fixStatusMessages * Merge refs/heads/master into fixStatusMessages * Merge refs/heads/master into fixStatusMessages
prysmaticlabs · Jun 1, 2020 · e715339 · e715339
1 parent 4ed0e43
commit e715339
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Showing 6 changed files with 141 additions and 32 deletions.
diff --git a/beacon-chain/blockchain/chain_info.go b/beacon-chain/blockchain/chain_info.go
@@ -1,7 +1,6 @@
 package blockchain
 
 import (
-	"bytes"
 	"context"
 	"time"
 
@@ -79,12 +78,6 @@ func (s *Service) FinalizedCheckpt() *ethpb.Checkpoint {
 		return &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
 	}
 
-	// If head state exists but there hasn't been a finalized check point,
-	// the check point's root should refer to genesis block root.
-	if bytes.Equal(s.finalizedCheckpt.Root, params.BeaconConfig().ZeroHash[:]) {
-		return &ethpb.Checkpoint{Root: s.genesisRoot[:]}
-	}
-
 	return state.CopyCheckpoint(s.finalizedCheckpt)
 }
 
@@ -94,12 +87,6 @@ func (s *Service) CurrentJustifiedCheckpt() *ethpb.Checkpoint {
 		return &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
 	}
 
-	// If head state exists but there hasn't been a justified check point,
-	// the check point root should refer to genesis block root.
-	if bytes.Equal(s.justifiedCheckpt.Root, params.BeaconConfig().ZeroHash[:]) {
-		return &ethpb.Checkpoint{Root: s.genesisRoot[:]}
-	}
-
 	return state.CopyCheckpoint(s.justifiedCheckpt)
 }
 
@@ -109,12 +96,6 @@ func (s *Service) PreviousJustifiedCheckpt() *ethpb.Checkpoint {
 		return &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
 	}
 
-	// If head state exists but there hasn't been a justified check point,
-	// the check point root should refer to genesis block root.
-	if bytes.Equal(s.prevJustifiedCheckpt.Root, params.BeaconConfig().ZeroHash[:]) {
-		return &ethpb.Checkpoint{Root: s.genesisRoot[:]}
-	}
-
 	return state.CopyCheckpoint(s.prevJustifiedCheckpt)
 }
 

diff --git a/beacon-chain/blockchain/service.go b/beacon-chain/blockchain/service.go
@@ -353,9 +353,9 @@ func (s *Service) saveGenesisData(ctx context.Context, genesisState *stateTrie.B
 		return errors.Wrap(err, "could save genesis block root")
 	}
 
-	genesisCheckpoint := &ethpb.Checkpoint{Root: genesisBlkRoot[:]}
+	// Finalized checkpoint at genesis is a zero hash.
+	genesisCheckpoint := genesisState.FinalizedCheckpoint()
 
-	// Add the genesis block to the fork choice store.
 	s.justifiedCheckpt = stateTrie.CopyCheckpoint(genesisCheckpoint)
 	s.prevJustifiedCheckpt = stateTrie.CopyCheckpoint(genesisCheckpoint)
 	s.bestJustifiedCheckpt = stateTrie.CopyCheckpoint(genesisCheckpoint)

diff --git a/beacon-chain/rpc/beacon/blocks.go b/beacon-chain/rpc/beacon/blocks.go
@@ -15,6 +15,7 @@ import (
 	"github.com/prysmaticlabs/prysm/beacon-chain/state/stateutil"
 	"github.com/prysmaticlabs/prysm/shared/bytesutil"
 	"github.com/prysmaticlabs/prysm/shared/pagination"
+	"github.com/prysmaticlabs/prysm/shared/params"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
 )
@@ -246,24 +247,47 @@ func (bs *Server) chainHeadRetrieval(ctx context.Context) (*ethpb.ChainHead, err
 		return nil, status.Errorf(codes.Internal, "Could not get head block root: %v", err)
 	}
 
+	isGenesis := func(cp *ethpb.Checkpoint) bool {
+		return bytesutil.ToBytes32(cp.Root) == params.BeaconConfig().ZeroHash && cp.Epoch == 0
+	}
+	// Retrieve genesis block in the event we have genesis checkpoints.
+	genBlock, err := bs.BeaconDB.GenesisBlock(ctx)
+	if err != nil || genBlock == nil || genBlock.Block == nil {
+		return nil, status.Error(codes.Internal, "Could not get genesis block")
+	}
+
+	var b *ethpb.SignedBeaconBlock
+
 	finalizedCheckpoint := bs.FinalizationFetcher.FinalizedCheckpt()
-	b, err := bs.BeaconDB.Block(ctx, bytesutil.ToBytes32(finalizedCheckpoint.Root))
-	if err != nil || b == nil || b.Block == nil {
-		return nil, status.Error(codes.Internal, "Could not get finalized block")
+	if isGenesis(finalizedCheckpoint) {
+		b = genBlock
+	} else {
+		b, err = bs.BeaconDB.Block(ctx, bytesutil.ToBytes32(finalizedCheckpoint.Root))
+		if err != nil || b == nil || b.Block == nil {
+			return nil, status.Error(codes.Internal, "Could not get finalized block")
+		}
 	}
 	finalizedSlot := b.Block.Slot
 
 	justifiedCheckpoint := bs.FinalizationFetcher.CurrentJustifiedCheckpt()
-	b, err = bs.BeaconDB.Block(ctx, bytesutil.ToBytes32(justifiedCheckpoint.Root))
-	if err != nil || b == nil || b.Block == nil {
-		return nil, status.Error(codes.Internal, "Could not get justified block")
+	if isGenesis(justifiedCheckpoint) {
+		b = genBlock
+	} else {
+		b, err = bs.BeaconDB.Block(ctx, bytesutil.ToBytes32(justifiedCheckpoint.Root))
+		if err != nil || b == nil || b.Block == nil {
+			return nil, status.Error(codes.Internal, "Could not get justified block")
+		}
 	}
 	justifiedSlot := b.Block.Slot
 
 	prevJustifiedCheckpoint := bs.FinalizationFetcher.PreviousJustifiedCheckpt()
-	b, err = bs.BeaconDB.Block(ctx, bytesutil.ToBytes32(prevJustifiedCheckpoint.Root))
-	if err != nil || b == nil || b.Block == nil {
-		return nil, status.Error(codes.Internal, "Could not get prev justified block")
+	if isGenesis(prevJustifiedCheckpoint) {
+		b = genBlock
+	} else {
+		b, err = bs.BeaconDB.Block(ctx, bytesutil.ToBytes32(prevJustifiedCheckpoint.Root))
+		if err != nil || b == nil || b.Block == nil {
+			return nil, status.Error(codes.Internal, "Could not get prev justified block")
+		}
 	}
 	prevJustifiedSlot := b.Block.Slot
 

diff --git a/beacon-chain/rpc/beacon/blocks_test.go b/beacon-chain/rpc/beacon/blocks_test.go
@@ -374,6 +374,18 @@ func TestServer_GetChainHead_NoFinalizedBlock(t *testing.T) {
 		t.Fatal(err)
 	}
 
+	genBlock := &ethpb.SignedBeaconBlock{Block: &ethpb.BeaconBlock{Slot: 0, ParentRoot: []byte{'G'}}}
+	if err := db.SaveBlock(context.Background(), genBlock); err != nil {
+		t.Fatal(err)
+	}
+	gRoot, err := stateutil.BlockRoot(genBlock.Block)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := db.SaveGenesisBlockRoot(context.Background(), gRoot); err != nil {
+		t.Fatal(err)
+	}
+
 	bs := &Server{
 		BeaconDB:    db,
 		HeadFetcher: &chainMock.ChainService{Block: &ethpb.SignedBeaconBlock{}, State: s},
@@ -405,6 +417,18 @@ func TestServer_GetChainHead_NoHeadBlock(t *testing.T) {
 func TestServer_GetChainHead(t *testing.T) {
 	db := dbTest.SetupDB(t)
 
+	genBlock := &ethpb.SignedBeaconBlock{Block: &ethpb.BeaconBlock{Slot: 0, ParentRoot: []byte{'G'}}}
+	if err := db.SaveBlock(context.Background(), genBlock); err != nil {
+		t.Fatal(err)
+	}
+	gRoot, err := stateutil.BlockRoot(genBlock.Block)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := db.SaveGenesisBlockRoot(context.Background(), gRoot); err != nil {
+		t.Fatal(err)
+	}
+
 	finalizedBlock := &ethpb.SignedBeaconBlock{Block: &ethpb.BeaconBlock{Slot: 1, ParentRoot: []byte{'A'}}}
 	if err := db.SaveBlock(context.Background(), finalizedBlock); err != nil {
 		t.Fatal(err)
@@ -522,6 +546,18 @@ func TestServer_StreamChainHead_ContextCanceled(t *testing.T) {
 func TestServer_StreamChainHead_OnHeadUpdated(t *testing.T) {
 	db := dbTest.SetupDB(t)
 
+	genBlock := &ethpb.SignedBeaconBlock{Block: &ethpb.BeaconBlock{Slot: 0, ParentRoot: []byte{'G'}}}
+	if err := db.SaveBlock(context.Background(), genBlock); err != nil {
+		t.Fatal(err)
+	}
+	gRoot, err := stateutil.BlockRoot(genBlock.Block)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := db.SaveGenesisBlockRoot(context.Background(), gRoot); err != nil {
+		t.Fatal(err)
+	}
+
 	finalizedBlock := &ethpb.SignedBeaconBlock{Block: &ethpb.BeaconBlock{Slot: 1, ParentRoot: []byte{'A'}}}
 	if err := db.SaveBlock(context.Background(), finalizedBlock); err != nil {
 		t.Fatal(err)

diff --git a/beacon-chain/sync/rpc_status.go b/beacon-chain/sync/rpc_status.go
@@ -250,6 +250,7 @@ func (r *Service) validateStatusMessage(ctx context.Context, msg *pb.Status, str
 	}
 	genesis := r.chain.GenesisTime()
 	finalizedEpoch := r.chain.FinalizedCheckpt().Epoch
+	finalizedRoot := r.chain.FinalizedCheckpt().Root
 	maxEpoch := slotutil.EpochsSinceGenesis(genesis)
 	// It would take a minimum of 2 epochs to finalize a
 	// previous epoch
@@ -265,6 +266,12 @@ func (r *Service) validateStatusMessage(ctx context.Context, msg *pb.Status, str
 	if finalizedEpoch < msg.FinalizedEpoch {
 		return nil
 	}
+	finalizedAtGenesis := (finalizedEpoch == msg.FinalizedEpoch) && finalizedEpoch == 0
+	rootIsEqual := bytes.Equal(finalizedRoot, msg.FinalizedRoot)
+	// If both peers are at genesis with the same root hash, then exit.
+	if finalizedAtGenesis && rootIsEqual {
+		return nil
+	}
 	if !r.db.IsFinalizedBlock(context.Background(), bytesutil.ToBytes32(msg.FinalizedRoot)) {
 		return errInvalidFinalizedRoot
 	}

diff --git a/beacon-chain/sync/rpc_status_test.go b/beacon-chain/sync/rpc_status_test.go
@@ -24,7 +24,7 @@ import (
 	"github.com/prysmaticlabs/prysm/shared/testutil"
 )
 
-func TestHelloRPCHandler_Disconnects_OnForkVersionMismatch(t *testing.T) {
+func TestStatusRPCHandler_Disconnects_OnForkVersionMismatch(t *testing.T) {
 	p1 := p2ptest.NewTestP2P(t)
 	p2 := p2ptest.NewTestP2P(t)
 	p1.Connect(p2)
@@ -99,7 +99,68 @@ func TestHelloRPCHandler_Disconnects_OnForkVersionMismatch(t *testing.T) {
 	}
 }
 
-func TestHelloRPCHandler_ReturnsHelloMessage(t *testing.T) {
+func TestStatusRPCHandler_ConnectsOnGenesis(t *testing.T) {
+	p1 := p2ptest.NewTestP2P(t)
+	p2 := p2ptest.NewTestP2P(t)
+	p1.Connect(p2)
+	if len(p1.Host.Network().Peers()) != 1 {
+		t.Error("Expected peers to be connected")
+	}
+	root := [32]byte{}
+
+	r := &Service{p2p: p1,
+		chain: &mock.ChainService{
+			Fork: &pb.Fork{
+				PreviousVersion: params.BeaconConfig().GenesisForkVersion,
+				CurrentVersion:  params.BeaconConfig().GenesisForkVersion,
+			},
+			FinalizedCheckPoint: &ethpb.Checkpoint{
+				Epoch: 0,
+				Root:  params.BeaconConfig().ZeroHash[:],
+			},
+			Genesis:        time.Now(),
+			ValidatorsRoot: [32]byte{'A'},
+		}}
+	pcl := protocol.ID("/testing")
+
+	var wg sync.WaitGroup
+	wg.Add(1)
+	p2.Host.SetStreamHandler(pcl, func(stream network.Stream) {
+		defer wg.Done()
+		expectSuccess(t, r, stream)
+		out := &pb.Status{}
+		if err := r.p2p.Encoding().DecodeWithLength(stream, out); err != nil {
+			t.Fatal(err)
+		}
+		if !bytes.Equal(out.FinalizedRoot, root[:]) {
+			t.Errorf("Expected finalized root of %#x but got %#x", root, out.FinalizedRoot)
+		}
+	})
+
+	stream1, err := p1.Host.NewStream(context.Background(), p2.Host.ID(), pcl)
+	if err != nil {
+		t.Fatal(err)
+	}
+	digest, err := r.forkDigest()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = r.statusRPCHandler(context.Background(), &pb.Status{ForkDigest: digest[:], FinalizedRoot: params.BeaconConfig().ZeroHash[:]}, stream1)
+	if err != nil {
+		t.Errorf("Expected no error but got %v", err)
+	}
+
+	if testutil.WaitTimeout(&wg, 1*time.Second) {
+		t.Fatal("Did not receive stream within 1 sec")
+	}
+
+	if len(p1.Host.Network().Peers()) != 1 {
+		t.Error("handler disconnected with peer")
+	}
+}
+
+func TestStatusRPCHandler_ReturnsHelloMessage(t *testing.T) {
 	p1 := p2ptest.NewTestP2P(t)
 	p2 := p2ptest.NewTestP2P(t)
 	p1.Connect(p2)