Merge pull request #982 from nspcc-dev/neo3/protocol/getblockdata

protocol: implement getblockdata p2p command

pkg/network/message.go

@@ -46,6 +46,7 @@ const (
 	CMDMempool      CommandType = 0x25
 	CMDInv          CommandType = 0x27
 	CMDGetData      CommandType = 0x28
+	CMDGetBlockData CommandType = 0x29
 	CMDUnknown      CommandType = 0x2a
 	CMDTX           CommandType = 0x2b
 	CMDBlock        CommandType = 0x2c
@@ -123,6 +124,8 @@ func (m *Message) decodePayload(br *io.BinReader) error {
 		fallthrough
 	case CMDGetHeaders:
 		p = &payload.GetBlocks{}
+	case CMDGetBlockData:
+		p = &payload.GetBlockData{}
 	case CMDHeaders:
 		p = &payload.Headers{}
 	case CMDTX:

pkg/network/message_string.go

@@ -20,6 +20,7 @@ func _() {
 	_ = x[CMDMempool-37]
 	_ = x[CMDInv-39]
 	_ = x[CMDGetData-40]
+	_ = x[CMDGetBlockData-41]
 	_ = x[CMDUnknown-42]
 	_ = x[CMDTX-43]
 	_ = x[CMDBlock-44]
@@ -38,11 +39,10 @@ const (
 	_CommandType_name_2 = "CMDPingCMDPong"
 	_CommandType_name_3 = "CMDGetHeadersCMDHeaders"
 	_CommandType_name_4 = "CMDGetBlocksCMDMempool"
-	_CommandType_name_5 = "CMDInvCMDGetData"
-	_CommandType_name_6 = "CMDUnknownCMDTXCMDBlockCMDConsensus"
-	_CommandType_name_7 = "CMDRejectCMDFilterLoadCMDFilterAddCMDFilterClear"
-	_CommandType_name_8 = "CMDMerkleBlock"
-	_CommandType_name_9 = "CMDAlert"
+	_CommandType_name_5 = "CMDInvCMDGetDataCMDGetBlockDataCMDUnknownCMDTXCMDBlockCMDConsensus"
+	_CommandType_name_6 = "CMDRejectCMDFilterLoadCMDFilterAddCMDFilterClear"
+	_CommandType_name_7 = "CMDMerkleBlock"
+	_CommandType_name_8 = "CMDAlert"
 )
 
 var (
@@ -51,9 +51,8 @@ var (
 	_CommandType_index_2 = [...]uint8{0, 7, 14}
 	_CommandType_index_3 = [...]uint8{0, 13, 23}
 	_CommandType_index_4 = [...]uint8{0, 12, 22}
-	_CommandType_index_5 = [...]uint8{0, 6, 16}
-	_CommandType_index_6 = [...]uint8{0, 10, 15, 23, 35}
-	_CommandType_index_7 = [...]uint8{0, 9, 22, 34, 48}
+	_CommandType_index_5 = [...]uint8{0, 6, 16, 31, 41, 46, 54, 66}
+	_CommandType_index_6 = [...]uint8{0, 9, 22, 34, 48}
 )
 
 func (i CommandType) String() string {
@@ -72,19 +71,16 @@ func (i CommandType) String() string {
 	case 36 <= i && i <= 37:
 		i -= 36
 		return _CommandType_name_4[_CommandType_index_4[i]:_CommandType_index_4[i+1]]
-	case 39 <= i && i <= 40:
+	case 39 <= i && i <= 45:
 		i -= 39
 		return _CommandType_name_5[_CommandType_index_5[i]:_CommandType_index_5[i+1]]
-	case 42 <= i && i <= 45:
-		i -= 42
-		return _CommandType_name_6[_CommandType_index_6[i]:_CommandType_index_6[i+1]]
 	case 47 <= i && i <= 50:
 		i -= 47
-		return _CommandType_name_7[_CommandType_index_7[i]:_CommandType_index_7[i+1]]
+		return _CommandType_name_6[_CommandType_index_6[i]:_CommandType_index_6[i+1]]
 	case i == 56:
-		return _CommandType_name_8
+		return _CommandType_name_7
 	case i == 64:
-		return _CommandType_name_9
+		return _CommandType_name_8
 	default:
 		return "CommandType(" + strconv.FormatInt(int64(i), 10) + ")"
 	}

pkg/network/payload/getblockdata.go

@@ -0,0 +1,39 @@
+package payload
+
+import (
+	"errors"
+
+	"github.com/nspcc-dev/neo-go/pkg/io"
+)
+
+// maximum number of blocks to query about
+const maxBlockCount = 500
+
+// GetBlockData payload
+type GetBlockData struct {
+	IndexStart uint32
+	Count      uint16
+}
+
+// NewGetBlockData returns GetBlockData payload with specified start index and count
+func NewGetBlockData(indexStart uint32, count uint16) *GetBlockData {
+	return &GetBlockData{
+		IndexStart: indexStart,
+		Count:      count,
+	}
+}
+
+// DecodeBinary implements Serializable interface.
+func (d *GetBlockData) DecodeBinary(br *io.BinReader) {
+	d.IndexStart = br.ReadU32LE()
+	d.Count = br.ReadU16LE()
+	if d.Count == 0 || d.Count > maxBlockCount {
+		br.Err = errors.New("invalid block count")
+	}
+}
+
+// EncodeBinary implements Serializable interface.
+func (d *GetBlockData) EncodeBinary(bw *io.BinWriter) {
+	bw.WriteU32LE(d.IndexStart)
+	bw.WriteU16LE(d.Count)
+}

pkg/network/payload/getblockdata_test.go

@@ -0,0 +1,25 @@
+package payload
+
+import (
+	"testing"
+
+	"github.com/nspcc-dev/neo-go/pkg/internal/testserdes"
+	"github.com/stretchr/testify/require"
+)
+
+func TestGetBlockDataEncodeDecode(t *testing.T) {
+	d := NewGetBlockData(123, 100)
+	testserdes.EncodeDecodeBinary(t, d, new(GetBlockData))
+
+	// invalid block count
+	d = NewGetBlockData(5, 0)
+	data, err := testserdes.EncodeBinary(d)
+	require.NoError(t, err)
+	require.Error(t, testserdes.DecodeBinary(data, new(GetBlockData)))
+
+	// invalid block count
+	d = NewGetBlockData(5, maxBlockCount+1)
+	data, err = testserdes.EncodeBinary(d)
+	require.NoError(t, err)
+	require.Error(t, testserdes.DecodeBinary(data, new(GetBlockData)))
+}

pkg/network/server.go

@@ -560,6 +560,19 @@ func (s *Server) handleGetBlocksCmd(p Peer, gb *payload.GetBlocks) error {
 	return p.EnqueueP2PMessage(msg)
 }
 
+// handleGetBlockDataCmd processes the getblockdata request.
+func (s *Server) handleGetBlockDataCmd(p Peer, gbd *payload.GetBlockData) error {
+	for i := gbd.IndexStart; i < gbd.IndexStart+uint32(gbd.Count); i++ {
+		b, err := s.chain.GetBlock(s.chain.GetHeaderHash(int(i)))
+		if err != nil {
+			return err
+		}
+		msg := NewMessage(CMDBlock, b)
+		return p.EnqueueP2PMessage(msg)
+	}
+	return nil
+}
+
 // handleGetHeadersCmd processes the getheaders request.
 func (s *Server) handleGetHeadersCmd(p Peer, gh *payload.GetBlocks) error {
 	count := gh.Count
@@ -685,6 +698,9 @@ func (s *Server) handleMessage(peer Peer, msg *Message) error {
 		case CMDGetBlocks:
 			gb := msg.Payload.(*payload.GetBlocks)
 			return s.handleGetBlocksCmd(peer, gb)
+		case CMDGetBlockData:
+			gbd := msg.Payload.(*payload.GetBlockData)
+			return s.handleGetBlockDataCmd(peer, gbd)
 		case CMDGetData:
 			inv := msg.Payload.(*payload.Inventory)
 			return s.handleGetDataCmd(peer, inv)