Initial implementation of BIP0037.

Implement filteradd, filterclear, filterload, and merkleblock.

invvect.go

@@ -26,6 +26,7 @@ const (
 	InvTypeError         InvType = 0
 	InvTypeTx            InvType = 1
 	InvTypeBlock         InvType = 2
+	InvTypeFilteredBlock InvType = 3
 )
 
 // Map of service flags back to their constant names for pretty printing.
@@ -33,6 +34,7 @@ var ivStrings = map[InvType]string{
 	InvTypeError:         "ERROR",
 	InvTypeTx:            "MSG_TX",
 	InvTypeBlock:         "MSG_BLOCK",
+	InvTypeFilteredBlock: "MSG_FILTERED_BLOCK",
 }
 
 // String returns the InvType in human-readable form.

message.go

@@ -42,6 +42,10 @@ const (
 	cmdPong        = "pong"
 	cmdAlert       = "alert"
 	cmdMemPool     = "mempool"
+	cmdFilterAdd   = "filteradd"
+	cmdFilterClear = "filterclear"
+	cmdFilterLoad  = "filterload"
+	cmdMerkleBlock = "merkleblock"
 )
 
 // Message is an interface that describes a bitcoin message.  A type that
@@ -108,6 +112,18 @@ func makeEmptyMessage(command string) (Message, error) {
 	case cmdMemPool:
 		msg = &MsgMemPool{}
 
+	case cmdFilterAdd:
+		msg = &MsgFilterAdd{}
+
+	case cmdFilterClear:
+		msg = &MsgFilterClear{}
+
+	case cmdFilterLoad:
+		msg = &MsgFilterLoad{}
+
+	case cmdMerkleBlock:
+		msg = &MsgMerkleBlock{}
+
 	default:
 		return nil, fmt.Errorf("unhandled command [%s]", command)
 	}

message_test.go

@@ -68,6 +68,13 @@ func TestMessage(t *testing.T) {
 	msgHeaders := btcwire.NewMsgHeaders()
 	msgAlert := btcwire.NewMsgAlert([]byte("payload"), []byte("signature"))
 	msgMemPool := btcwire.NewMsgMemPool()
+	msgFilterAdd := btcwire.NewMsgFilterAdd([]byte{0x01})
+	msgFilterClear := btcwire.NewMsgFilterClear()
+	msgFilterLoad := btcwire.NewMsgFilterLoad([]byte{0x01}, 10, 0, btcwire.BloomUpdateNone)
+
+	//
+	bh := btcwire.NewBlockHeader(&btcwire.ShaHash{}, &btcwire.ShaHash{}, 0, 0)
+	msgMerkleBlock := btcwire.NewMsgMerkleBlock(bh)
 
 	tests := []struct {
 		in     btcwire.Message    // Value to encode
@@ -92,6 +99,10 @@ func TestMessage(t *testing.T) {
 		{msgHeaders, msgHeaders, pver, btcwire.MainNet, 25},
 		{msgAlert, msgAlert, pver, btcwire.MainNet, 42},
 		{msgMemPool, msgMemPool, pver, btcwire.MainNet, 24},
+		{msgFilterAdd, msgFilterAdd, pver, btcwire.MainNet, 26},
+		{msgFilterClear, msgFilterClear, pver, btcwire.MainNet, 24},
+		{msgFilterLoad, msgFilterLoad, pver, btcwire.MainNet, 35},
+		{msgMerkleBlock, msgMerkleBlock, pver, btcwire.MainNet, 110},
 	}
 
 	t.Logf("Running %d tests", len(tests))

msgfilteradd.go

@@ -0,0 +1,103 @@
+// Copyright (c) 2014 Conformal Systems LLC.
+// Use of this source code is governed by an ISC
+// license that can be found in the LICENSE file.
+
+package btcwire
+
+import (
+	"fmt"
+	"io"
+)
+
+const (
+	// MaxFilterAddDataSize is the maximum byte size of a data
+	// element to add to the Bloom filter.  It is equal to the
+	// maximum element size of a script.
+	MaxFilterAddDataSize = 520
+)
+
+// MsgFilterAdd implements the Message interface and represents a bitcoin filteradd
+// message which is used to add a data element to an existing Bloom filter.
+//
+// This message was not added until protocol version BIP0037Version.
+type MsgFilterAdd struct {
+	Data []byte
+}
+
+// BtcDecode decodes r using the bitcoin protocol encoding into the receiver.
+// This is part of the Message interface implementation.
+func (msg *MsgFilterAdd) BtcDecode(r io.Reader, pver uint32) error {
+	if pver < BIP0037Version {
+		str := fmt.Sprintf("filteradd message invalid for protocol "+
+			"version %d", pver)
+		return messageError("MsgFilterAdd.BtcDecode", str)
+	}
+
+	size, err := readVarInt(r, pver)
+	if err != nil {
+		return err
+	}
+
+	if size > MaxFilterAddDataSize {
+		str := fmt.Sprintf("filteradd size too large for message "+
+			"[size %v, max %v]", size, MaxFilterAddDataSize)
+		return messageError("MsgFilterAdd.BtcDecode", str)
+	}
+
+	msg.Data = make([]byte, size)
+	_, err = io.ReadFull(r, msg.Data)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// BtcEncode encodes the receiver to w using the bitcoin protocol encoding.
+// This is part of the Message interface implementation.
+func (msg *MsgFilterAdd) BtcEncode(w io.Writer, pver uint32) error {
+	if pver < BIP0037Version {
+		str := fmt.Sprintf("filteradd message invalid for protocol "+
+			"version %d", pver)
+		return messageError("MsgFilterAdd.BtcEncode", str)
+	}
+
+	size := len(msg.Data)
+	if size > MaxFilterAddDataSize {
+		str := fmt.Sprintf("filteradd size too large for message "+
+			"[size %v, max %v]", size, MaxFilterAddDataSize)
+		return messageError("MsgFilterAdd.BtcEncode", str)
+	}
+
+	err := writeVarInt(w, pver, uint64(size))
+	if err != nil {
+		return err
+	}
+
+	err = writeElement(w, msg.Data)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// Command returns the protocol command string for the message.  This is part
+// of the Message interface implementation.
+func (msg *MsgFilterAdd) Command() string {
+	return cmdFilterAdd
+}
+
+// MaxPayloadLength returns the maximum length the payload can be for the
+// receiver.  This is part of the Message interface implementation.
+func (msg *MsgFilterAdd) MaxPayloadLength(pver uint32) uint32 {
+	return MaxVarIntPayload + MaxFilterAddDataSize
+}
+
+// NewMsgFilterAdd returns a new bitcoin filteradd message that conforms to the Message
+// interface.  See MsgFilterAdd for details.
+func NewMsgFilterAdd(data []byte) *MsgFilterAdd {
+	return &MsgFilterAdd{
+		Data: data,
+	}
+}

msgfilteradd_test.go

@@ -0,0 +1,169 @@
+// Copyright (c) 2014 Conformal Systems LLC.
+// Use of this source code is governed by an ISC
+// license that can be found in the LICENSE file.
+
+package btcwire_test
+
+import (
+	"bytes"
+	"github.com/conformal/btcwire"
+	"io"
+	"testing"
+)
+
+// TestFilterCLearLatest tests the MsgFilterAdd API against the latest protocol version.
+func TestFilterAddLatest(t *testing.T) {
+	pver := btcwire.ProtocolVersion
+
+	data := []byte{0x01, 0x02}
+	msg := btcwire.NewMsgFilterAdd(data)
+
+	// Ensure the command is expected value.
+	wantCmd := "filteradd"
+	if cmd := msg.Command(); cmd != wantCmd {
+		t.Errorf("NewMsgFilterAdd: wrong command - got %v want %v",
+			cmd, wantCmd)
+	}
+
+	// Ensure max payload is expected value for latest protocol version.
+	wantPayload := uint32(529)
+	maxPayload := msg.MaxPayloadLength(pver)
+	if maxPayload != wantPayload {
+		t.Errorf("MaxPayloadLength: wrong max payload length for "+
+			"protocol version %d - got %v, want %v", pver,
+			maxPayload, wantPayload)
+	}
+
+	// Test encode with latest protocol version.
+	var buf bytes.Buffer
+	err := msg.BtcEncode(&buf, pver)
+	if err != nil {
+		t.Errorf("encode of MsgFilterAdd failed %v err <%v>", msg, err)
+	}
+
+	// Test decode with latest protocol version.
+	readmsg := btcwire.MsgFilterAdd{}
+	err = readmsg.BtcDecode(&buf, pver)
+	if err != nil {
+		t.Errorf("decode of MsgFilterAdd failed [%v] err <%v>", buf, err)
+	}
+
+	return
+}
+
+// TestFilterAddCrossProtocol tests the MsgFilterAdd API when encoding with the latest
+// protocol version and decoded with BIP0031Version.
+func TestFilterAddCrossProtocol(t *testing.T) {
+	data := []byte{0x01, 0x02}
+	msg := btcwire.NewMsgFilterAdd(data)
+
+	// Encode with old protocol version.
+	var buf bytes.Buffer
+	err := msg.BtcEncode(&buf, btcwire.BIP0037Version-1)
+	if err == nil {
+		t.Errorf("encode of MsgFilterAdd succeeded when it shouldn't have %v",
+			msg)
+	}
+
+	// Decode with old protocol version.
+	readmsg := btcwire.MsgFilterAdd{}
+	err = readmsg.BtcDecode(&buf, btcwire.BIP0031Version)
+	if err == nil {
+		t.Errorf("decode of MsgFilterAdd succeeded when it shouldn't have %v",
+			msg)
+	}
+}
+
+// TestFilterAddMaxDataSize tests the MsgFilterAdd API maximum data size.
+func TestFilterAddMaxDataSize(t *testing.T) {
+	data := bytes.Repeat([]byte{0xff}, 521)
+	msg := btcwire.NewMsgFilterAdd(data)
+
+	// Encode with latest protocol version.
+	var buf bytes.Buffer
+	err := msg.BtcEncode(&buf, btcwire.ProtocolVersion)
+	if err == nil {
+		t.Errorf("encode of MsgFilterAdd succeeded when it shouldn't have %v",
+			msg)
+	}
+
+	// Decode with latest protocol version.
+	readbuf := bytes.NewReader(data)
+	err = msg.BtcDecode(readbuf, btcwire.ProtocolVersion)
+	if err == nil {
+		t.Errorf("decode of MsgFilterAdd succeeded when it shouldn't have %v",
+			msg)
+	}
+}
+
+// TestFilterAddWireErrors performs negative tests against wire encode and decode
+// of MsgFilterAdd to confirm error paths work correctly.
+func TestFilterAddWireErrors(t *testing.T) {
+	pver := btcwire.ProtocolVersion
+
+	tests := []struct {
+		in       *btcwire.MsgFilterAdd // Value to encode
+		buf      []byte                // Wire encoding
+		pver     uint32                // Protocol version for wire encoding
+		max      int                   // Max size of fixed buffer to induce errors
+		writeErr error                 // Expected write error
+		readErr  error                 // Expected read error
+	}{
+		// Latest protocol version with intentional read/write errors.
+		{
+			&btcwire.MsgFilterAdd{Data: []byte{0x01, 0x02, 0x03, 0x04}},
+			[]byte{
+				0x05,             // Varint for size of data
+				0x02, 0x03, 0x04, // Data
+			},
+			pver,
+			2,
+			io.ErrShortWrite,
+			io.ErrUnexpectedEOF,
+		},
+		{
+			&btcwire.MsgFilterAdd{Data: []byte{0x01, 0x02, 0x03, 0x04}},
+			[]byte{
+				0x05,             // Varint for size of data
+				0x02, 0x03, 0x04, // Data
+			},
+			pver,
+			0,
+			io.ErrShortWrite,
+			io.EOF,
+		},
+		{
+			&btcwire.MsgFilterAdd{Data: []byte{0x01, 0x02, 0x03, 0x04}},
+			[]byte{
+				0x05,             // Varint for size of data
+				0x02, 0x03, 0x04, // Data
+			},
+			pver,
+			1,
+			io.ErrShortWrite,
+			io.EOF,
+		},
+	}
+
+	t.Logf("Running %d tests", len(tests))
+	for i, test := range tests {
+		// Encode to wire format.
+		w := newFixedWriter(test.max)
+		err := test.in.BtcEncode(w, test.pver)
+		if err != test.writeErr {
+			t.Errorf("BtcEncode #%d wrong error got: %v, want: %v",
+				i, err, test.writeErr)
+			continue
+		}
+
+		// Decode from wire format.
+		var msg btcwire.MsgFilterAdd
+		r := newFixedReader(test.max, test.buf)
+		err = msg.BtcDecode(r, test.pver)
+		if err != test.readErr {
+			t.Errorf("BtcDecode #%d wrong error got: %v, want: %v",
+				i, err, test.readErr)
+			continue
+		}
+	}
+}

msgfilterclear.go

@@ -0,0 +1,58 @@
+// Copyright (c) 2014 Conformal Systems LLC.
+// Use of this source code is governed by an ISC
+// license that can be found in the LICENSE file.
+
+package btcwire
+
+import (
+	"fmt"
+	"io"
+)
+
+// MsgFilterClear implements the Message interface and represents a bitcoin filterclear
+// message which is used to reset a Bloom filter.
+//
+// This message was not added until protocol version BIP0037Version.
+type MsgFilterClear struct{}
+
+// BtcDecode decodes r using the bitcoin protocol encoding into the receiver.
+// This is part of the Message interface implementation.
+func (msg *MsgFilterClear) BtcDecode(r io.Reader, pver uint32) error {
+	if pver < BIP0037Version {
+		str := fmt.Sprintf("filterclear message invalid for protocol "+
+			"version %d", pver)
+		return messageError("MsgFilterClear.BtcDecode", str)
+	}
+
+	return nil
+}
+
+// BtcEncode encodes the receiver to w using the bitcoin protocol encoding.
+// This is part of the Message interface implementation.
+func (msg *MsgFilterClear) BtcEncode(w io.Writer, pver uint32) error {
+	if pver < BIP0037Version {
+		str := fmt.Sprintf("filterclear message invalid for protocol "+
+			"version %d", pver)
+		return messageError("MsgFilterClear.BtcEncode", str)
+	}
+
+	return nil
+}
+
+// Command returns the protocol command string for the message.  This is part
+// of the Message interface implementation.
+func (msg *MsgFilterClear) Command() string {
+	return cmdFilterClear
+}
+
+// MaxPayloadLength returns the maximum length the payload can be for the
+// receiver.  This is part of the Message interface implementation.
+func (msg *MsgFilterClear) MaxPayloadLength(pver uint32) uint32 {
+	return 0
+}
+
+// NewMsgFilterClear returns a new bitcoin filterclear message that conforms to the Message
+// interface.  See MsgFilterClear for details.
+func NewMsgFilterClear() *MsgFilterClear {
+	return &MsgFilterClear{}
+}

msgfilterclear_test.go

@@ -0,0 +1,72 @@
+// Copyright (c) 2014 Conformal Systems LLC.
+// Use of this source code is governed by an ISC
+// license that can be found in the LICENSE file.
+
+package btcwire_test
+
+import (
+	"bytes"
+	"github.com/conformal/btcwire"
+	"testing"
+)
+
+// TestFilterCLearLatest tests the MsgFilterClear API against the latest protocol version.
+func TestFilterClearLatest(t *testing.T) {
+	pver := btcwire.ProtocolVersion
+
+	msg := btcwire.NewMsgFilterClear()
+
+	// Ensure the command is expected value.
+	wantCmd := "filterclear"
+	if cmd := msg.Command(); cmd != wantCmd {
+		t.Errorf("NewMsgFilterClear: wrong command - got %v want %v",
+			cmd, wantCmd)
+	}
+
+	// Ensure max payload is expected value for latest protocol version.
+	wantPayload := uint32(0)
+	maxPayload := msg.MaxPayloadLength(pver)
+	if maxPayload != wantPayload {
+		t.Errorf("MaxPayloadLength: wrong max payload length for "+
+			"protocol version %d - got %v, want %v", pver,
+			maxPayload, wantPayload)
+	}
+
+	// Test encode with latest protocol version.
+	var buf bytes.Buffer
+	err := msg.BtcEncode(&buf, pver)
+	if err != nil {
+		t.Errorf("encode of MsgFilterClear failed %v err <%v>", msg, err)
+	}
+
+	// Test decode with latest protocol version.
+	readmsg := btcwire.NewMsgFilterClear()
+	err = readmsg.BtcDecode(&buf, pver)
+	if err != nil {
+		t.Errorf("decode of MsgFilterClear failed [%v] err <%v>", buf, err)
+	}
+
+	return
+}
+
+// TestFilterClearCrossProtocol tests the MsgFilterClear API when encoding with the latest
+// protocol version and decoded with BIP0031Version.
+func TestFilterClearCrossProtocol(t *testing.T) {
+	msg := btcwire.NewMsgFilterClear()
+
+	// Encode with old protocol version.
+	var buf bytes.Buffer
+	err := msg.BtcEncode(&buf, btcwire.BIP0037Version-1)
+	if err == nil {
+		t.Errorf("encode of MsgFilterClear succeeded when it shouldn't have %v",
+			msg)
+	}
+
+	// Decode with old protocol version.
+	readmsg := btcwire.NewMsgFilterClear()
+	err = readmsg.BtcDecode(&buf, btcwire.BIP0031Version)
+	if err == nil {
+		t.Errorf("decode of MsgFilterClear succeeded when it shouldn't have %v",
+			msg)
+	}
+}

msgfilterload.go

@@ -0,0 +1,160 @@
+// Copyright (c) 2014 Conformal Systems LLC.
+// Use of this source code is governed by an ISC
+// license that can be found in the LICENSE file.
+
+package btcwire
+
+import (
+	"fmt"
+	"io"
+)
+
+type BloomUpdateType uint8
+
+const (
+	// BloomUpdateNone indicates the filter is not adjusted when a match is found.
+	BloomUpdateNone BloomUpdateType = 0
+
+	// BloomUpdateAll indicates if the filter matches any data element in a
+	// scriptPubKey, the outpoint is serialized and inserted into the filter.
+	BloomUpdateAll BloomUpdateType = 1
+
+	// BloomUpdateP2PubkeyOnly indicates if the filter matches a data element in
+	// a scriptPubkey and the script is of the standard payToPybKey or payToMultiSig,
+	// the outpoint is inserted into the filter.
+	BloomUpdateP2PubkeyOnly BloomUpdateType = 2
+)
+
+const (
+	// MaxFilterLoadHashFuncs is the maximum number of hash functions to load
+	// into the Bloom filter.
+	MaxFilterLoadHashFuncs = 50
+
+	// MaxFilterLoadFilterSize is the maximum size in bytes a filter may be.
+	MaxFilterLoadFilterSize = 36000
+)
+
+// MsgFilterLoad implements the Message interface and represents a bitcoin filterload
+// message which is used to reset a Bloom filter.
+//
+// This message was not added until protocol version BIP0037Version.
+type MsgFilterLoad struct {
+	Filter    []byte
+	HashFuncs uint32
+	Tweak     uint32
+	Flags     BloomUpdateType
+}
+
+// BtcDecode decodes r using the bitcoin protocol encoding into the receiver.
+// This is part of the Message interface implementation.
+func (msg *MsgFilterLoad) BtcDecode(r io.Reader, pver uint32) error {
+	if pver < BIP0037Version {
+		str := fmt.Sprintf("filterload message invalid for protocol "+
+			"version %d", pver)
+		return messageError("MsgFilterLoad.BtcDecode", str)
+	}
+
+	// Read num filter and limit to max.
+	size, err := readVarInt(r, pver)
+	if err != nil {
+		return err
+	}
+	if size > MaxFilterLoadFilterSize {
+		str := fmt.Sprintf("filterload filter size too large for message "+
+			"[size %v, max %v]", size, MaxFilterLoadFilterSize)
+		return messageError("MsgFilterLoad.BtcDecode", str)
+	}
+
+	msg.Filter = make([]byte, size)
+	_, err = io.ReadFull(r, msg.Filter)
+	if err != nil {
+		return err
+	}
+
+	err = readElements(r, &msg.HashFuncs, &msg.Tweak, &msg.Flags)
+	if err != nil {
+		return err
+	}
+
+	if msg.HashFuncs > MaxFilterLoadHashFuncs {
+		str := fmt.Sprintf("too many filter hash functions for message "+
+			"[count %v, max %v]", msg.HashFuncs, MaxFilterLoadHashFuncs)
+		return messageError("MsgFilterLoad.BtcDecode", str)
+	}
+
+	return nil
+}
+
+// BtcEncode encodes the receiver to w using the bitcoin protocol encoding.
+// This is part of the Message interface implementation.
+func (msg *MsgFilterLoad) BtcEncode(w io.Writer, pver uint32) error {
+	if pver < BIP0037Version {
+		str := fmt.Sprintf("filterload message invalid for protocol "+
+			"version %d", pver)
+		return messageError("MsgFilterLoad.BtcEncode", str)
+	}
+
+	size := len(msg.Filter)
+	if size > MaxFilterLoadFilterSize {
+		str := fmt.Sprintf("filterload filter size too large for message "+
+			"[size %v, max %v]", size, MaxFilterLoadFilterSize)
+		return messageError("MsgFilterLoad.BtcEncode", str)
+	}
+
+	if msg.HashFuncs > MaxFilterLoadHashFuncs {
+		str := fmt.Sprintf("too many filter hash functions for message "+
+			"[count %v, max %v]", msg.HashFuncs, MaxFilterLoadHashFuncs)
+		return messageError("MsgFilterLoad.BtcEncode", str)
+	}
+
+	err := writeVarInt(w, pver, uint64(size))
+	if err != nil {
+		return err
+	}
+	err = writeElements(w, msg.Filter, msg.HashFuncs, msg.Tweak, msg.Flags)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// Serialize encodes the transaction to w using a format that suitable for
+// long-term storage such as a database while respecting the Version field in
+// the transaction.  This function differs from BtcEncode in that BtcEncode
+// encodes the transaction to the bitcoin wire protocol in order to be sent
+// across the network.  The wire encoding can technically differ depending on
+// the protocol version and doesn't even really need to match the format of a
+// stored transaction at all.  As of the time this comment was written, the
+// encoded transaction is the same in both instances, but there is a distinct
+// difference and separating the two allows the API to be flexible enough to
+// deal with changes.
+func (msg *MsgFilterLoad) Serialize(w io.Writer) error {
+	// At the current time, there is no difference between the wire encoding
+	// at protocol version 0 and the stable long-term storage format.  As
+	// a result, make use of BtcEncode.
+	return msg.BtcEncode(w, BIP0037Version)
+}
+
+// Command returns the protocol command string for the message.  This is part
+// of the Message interface implementation.
+func (msg *MsgFilterLoad) Command() string {
+	return cmdFilterLoad
+}
+
+// MaxPayloadLength returns the maximum length the payload can be for the
+// receiver.  This is part of the Message interface implementation.
+func (msg *MsgFilterLoad) MaxPayloadLength(pver uint32) uint32 {
+	return MaxVarIntPayload + MaxFilterLoadFilterSize + 4 + 4 + 1
+}
+
+// NewMsgFilterLoad returns a new bitcoin filterload message that conforms to the Message
+// interface.  See MsgFilterLoad for details.
+func NewMsgFilterLoad(filter []byte, hashFuncs uint32, tweak uint32, flags BloomUpdateType) *MsgFilterLoad {
+	return &MsgFilterLoad{
+		Filter:    filter,
+		HashFuncs: hashFuncs,
+		Tweak:     tweak,
+		Flags:     flags,
+	}
+}

msgfilterload_test.go

@@ -0,0 +1,223 @@
+// Copyright (c) 2014 Conformal Systems LLC.
+// Use of this source code is governed by an ISC
+// license that can be found in the LICENSE file.
+
+package btcwire_test
+
+import (
+	"bytes"
+	"github.com/conformal/btcwire"
+	"io"
+	"testing"
+)
+
+// TestFilterCLearLatest tests the MsgFilterLoad API against the latest protocol version.
+func TestFilterLoadLatest(t *testing.T) {
+	pver := btcwire.ProtocolVersion
+
+	data := []byte{0x01, 0x02}
+	msg := btcwire.NewMsgFilterLoad(data, 10, 0, 0)
+
+	// Ensure the command is expected value.
+	wantCmd := "filterload"
+	if cmd := msg.Command(); cmd != wantCmd {
+		t.Errorf("NewMsgFilterLoad: wrong command - got %v want %v",
+			cmd, wantCmd)
+	}
+
+	// Ensure max payadd is expected value for latest protocol version.
+	wantPayload := uint32(36018)
+	maxPayload := msg.MaxPayloadLength(pver)
+	if maxPayload != wantPayload {
+		t.Errorf("MaxPayLoadLength: wrong max payload length for "+
+			"protocol version %d - got %v, want %v", pver,
+			maxPayload, wantPayload)
+	}
+
+	// Test encode with latest protocol version.
+	var buf bytes.Buffer
+	err := msg.BtcEncode(&buf, pver)
+	if err != nil {
+		t.Errorf("encode of MsgFilterLoad failed %v err <%v>", msg, err)
+	}
+
+	// Test decode with latest protocol version.
+	readmsg := btcwire.MsgFilterLoad{}
+	err = readmsg.BtcDecode(&buf, pver)
+	if err != nil {
+		t.Errorf("decode of MsgFilterLoad failed [%v] err <%v>", buf, err)
+	}
+
+	return
+}
+
+// TestFilterLoadCrossProtocol tests the MsgFilterLoad API when encoding with the latest
+// protocol version and decoded with BIP0031Version.
+func TestFilterLoadCrossProtocol(t *testing.T) {
+	data := []byte{0x01, 0x02}
+	msg := btcwire.NewMsgFilterLoad(data, 10, 0, 0)
+
+	// Encode with old protocol version.
+	var buf bytes.Buffer
+	err := msg.BtcEncode(&buf, btcwire.BIP0037Version-1)
+	if err == nil {
+		t.Errorf("encode of MsgFilterLoad succeeded when it shouldn't have %v",
+			msg)
+	}
+
+	// Decode with old protocol version.
+	readmsg := btcwire.MsgFilterLoad{}
+	err = readmsg.BtcDecode(&buf, btcwire.BIP0031Version)
+	if err == nil {
+		t.Errorf("decode of MsgFilterLoad succeeded when it shouldn't have %v",
+			msg)
+	}
+}
+
+// TestFilterLoadMaxFilterSize tests the MsgFilterLoad API maximum filter size.
+func TestFilterLoadMaxFilterSize(t *testing.T) {
+	data := bytes.Repeat([]byte{0xff}, 36001)
+	msg := btcwire.NewMsgFilterLoad(data, 10, 0, 0)
+
+	// Encode with latest protocol version.
+	var buf bytes.Buffer
+	err := msg.BtcEncode(&buf, btcwire.ProtocolVersion)
+	if err == nil {
+		t.Errorf("encode of MsgFilterLoad succeeded when it shouldn't have %v",
+			msg)
+	}
+
+	// Decode with latest protocol version.
+	readbuf := bytes.NewReader(data)
+	err = msg.BtcDecode(readbuf, btcwire.ProtocolVersion)
+	if err == nil {
+		t.Errorf("decode of MsgFilterLoad succeeded when it shouldn't have %v",
+			msg)
+	}
+}
+
+// TestFilterLoadMaxHashFuncsSize tests the MsgFilterLoad API maximum hash functions.
+func TestFilterLoadMaxHashFuncsSize(t *testing.T) {
+	data := bytes.Repeat([]byte{0xff}, 10)
+	msg := btcwire.NewMsgFilterLoad(data, 61, 0, 0)
+
+	// Encode with latest protocol version.
+	var buf bytes.Buffer
+	err := msg.BtcEncode(&buf, btcwire.ProtocolVersion)
+	if err == nil {
+		t.Errorf("encode of MsgFilterLoad succeeded when it shouldn't have %v",
+			msg)
+	}
+
+	newBuf := []byte{
+		0x0a,                                                       // filter size
+		0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, // filter
+		0x3d, 0x00, 0x00, 0x00, // max hash funcs
+		0x00, 0x00, 0x00, 0x00, // tweak
+		0x00, // update Type
+	}
+	// Decode with latest protocol version.
+	buf1 := bytes.NewBuffer(newBuf)
+	readbuf := bytes.NewReader(buf1.Bytes())
+	err = msg.BtcDecode(readbuf, btcwire.ProtocolVersion)
+	if err == nil {
+		t.Errorf("decode of MsgFilterLoad succeeded when it shouldn't have %v",
+			msg)
+	}
+}
+
+// TestFilterLoadWireErrors performs negative tests against wire encode and decode
+// of MsgFilterLoad to confirm error paths work correctly.
+func TestFilterLoadWireErrors(t *testing.T) {
+	pver := btcwire.ProtocolVersion
+
+	tests := []struct {
+		in       *btcwire.MsgFilterLoad // Value to encode
+		buf      []byte                 // Wire encoding
+		pver     uint32                 // Protocol version for wire encoding
+		max      int                    // Max size of fixed buffer to induce errors
+		writeErr error                  // Expected write error
+		readErr  error                  // Expected read error
+	}{
+		// Latest protocol version with intentional read/write errors.
+		{
+			&btcwire.MsgFilterLoad{
+				Filter:    []byte{0x01, 0x02, 0x03, 0x04},
+				HashFuncs: 10,
+				Tweak:     0,
+				Flags:     btcwire.BloomUpdateNone,
+			},
+			[]byte{
+				0x04,                   // Varint for size of Filter
+				0x01, 0x02, 0x03, 0x04, // Filter
+				0x00, 0x0a, // HashFuncs
+				0x00, 0x00, // Tweak
+				0x00, // Flags
+			},
+			pver,
+			2,
+			io.ErrShortWrite,
+			io.ErrUnexpectedEOF,
+		},
+		{
+			&btcwire.MsgFilterLoad{
+				Filter:    []byte{0x01, 0x02, 0x03, 0x04},
+				HashFuncs: 10,
+				Tweak:     0,
+				Flags:     btcwire.BloomUpdateNone,
+			},
+			[]byte{
+				0x04,                   // Varint for size of Filter
+				0x01, 0x02, 0x03, 0x04, // Filter
+				0x00, 0x0a, // HashFuncs
+				0x00, 0x00, // Tweak
+				0x00, // Flags
+			},
+			pver,
+			0,
+			io.ErrShortWrite,
+			io.EOF,
+		},
+		{
+			&btcwire.MsgFilterLoad{
+				Filter:    []byte{0x01, 0x02, 0x03, 0x04},
+				HashFuncs: 10,
+				Tweak:     0,
+				Flags:     btcwire.BloomUpdateNone,
+			},
+			[]byte{
+				0x04,                   // Varint for size of Filter
+				0x01, 0x02, 0x03, 0x04, // Filter
+				0x00, 0x0a, // HashFuncs
+				0x00, 0x00, // Tweak
+				0x00, // Flags
+			},
+			pver,
+			10,
+			io.ErrShortWrite,
+			io.ErrUnexpectedEOF,
+		},
+	}
+
+	t.Logf("Running %d tests", len(tests))
+	for i, test := range tests {
+		// Encode to wire format.
+		w := newFixedWriter(test.max)
+		err := test.in.BtcEncode(w, test.pver)
+		if err != test.writeErr {
+			t.Errorf("BtcEncode #%d wrong error got: %v, want: %v",
+				i, err, test.writeErr)
+			continue
+		}
+
+		// Decode from wire format.
+		var msg btcwire.MsgFilterLoad
+		r := newFixedReader(test.max, test.buf)
+		err = msg.BtcDecode(r, test.pver)
+		if err != test.readErr {
+			t.Errorf("BtcDecode #%d wrong error got: %v, want: %v",
+				i, err, test.readErr)
+			continue
+		}
+	}
+}

msgmerkleblock.go

@@ -0,0 +1,163 @@
+// Copyright (c) 2014 Conformal Systems LLC.
+// Use of this source code is governed by an ISC
+// license that can be found in the LICENSE file.
+
+package btcwire
+
+import (
+	"fmt"
+	"io"
+)
+
+// MsgMerkleBlock implements the Message interface and represents a bitcoin merkleblock
+// message which is used to reset a Bloom filter.
+//
+// This message was not added until protocol version BIP0037Version.
+type MsgMerkleBlock struct {
+	Header       BlockHeader
+	Transactions uint32
+	Hashes       []*ShaHash
+	Flags        []byte
+}
+
+// AddTxHash adds a new transaction hash to the message.
+func (msg *MsgMerkleBlock) AddTxHash(hash *ShaHash) error {
+	if len(msg.Hashes)+1 > maxTxPerBlock {
+		str := fmt.Sprintf("too many tx hashes for message [max %v]",
+			maxTxPerBlock)
+		return messageError("MsgMerkleBlock.AddTxHash", str)
+	}
+
+	msg.Hashes = append(msg.Hashes, hash)
+	return nil
+}
+
+// BtcDecode decodes r using the bitcoin protocol encoding into the receiver.
+// This is part of the Message interface implementation.
+func (msg *MsgMerkleBlock) BtcDecode(r io.Reader, pver uint32) error {
+	if pver < BIP0037Version {
+		str := fmt.Sprintf("merkleblock message invalid for protocol "+
+			"version %d", pver)
+		return messageError("MsgMerkleBlock.BtcDecode", str)
+	}
+
+	err := readBlockHeader(r, pver, &msg.Header)
+	if err != nil {
+		return err
+	}
+
+	err = readElement(r, &msg.Transactions)
+	if err != nil {
+		return err
+	}
+
+	// Read num block locator hashes and limit to max.
+	count, err := readVarInt(r, pver)
+	if err != nil {
+		return err
+	}
+	if count > maxTxPerBlock {
+		str := fmt.Sprintf("too many transaction hashes for message "+
+			"[count %v, max %v]", count, maxTxPerBlock)
+		return messageError("MsgMerkleBlock.BtcDecode", str)
+	}
+
+	msg.Hashes = make([]*ShaHash, 0, count)
+	for i := uint64(0); i < count; i++ {
+		sha := ShaHash{}
+		err := readElement(r, &sha)
+		if err != nil {
+			return err
+		}
+		msg.AddTxHash(&sha)
+	}
+
+	count, err = readVarInt(r, pver)
+	if err != nil {
+		return err
+	}
+
+	msg.Flags = make([]byte, 0, count)
+	err = readElement(r, &msg.Flags)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// BtcEncode encodes the receiver to w using the bitcoin protocol encoding.
+// This is part of the Message interface implementation.
+func (msg *MsgMerkleBlock) BtcEncode(w io.Writer, pver uint32) error {
+	if pver < BIP0037Version {
+		str := fmt.Sprintf("merkleblock message invalid for protocol "+
+			"version %d", pver)
+		return messageError("MsgMerkleBlock.BtcEncode", str)
+	}
+
+	// Read num transaction hashes and limit to max.
+	count := len(msg.Hashes)
+	if count > maxTxPerBlock {
+		str := fmt.Sprintf("too many transaction hashes for message "+
+			"[count %v, max %v]", count, maxTxPerBlock)
+		return messageError("MsgMerkleBlock.BtcDecode", str)
+	}
+
+	err := writeBlockHeader(w, pver, &msg.Header)
+	if err != nil {
+		return err
+	}
+
+	err = writeElement(w, msg.Transactions)
+	if err != nil {
+		return err
+	}
+
+	err = writeVarInt(w, pver, uint64(count))
+	if err != nil {
+		return err
+	}
+
+	for _, hash := range msg.Hashes {
+		err = writeElement(w, hash)
+		if err != nil {
+			return err
+		}
+	}
+
+	count = len(msg.Flags)
+	err = writeVarInt(w, pver, uint64(count))
+	if err != nil {
+		return err
+	}
+
+	err = writeElement(w, msg.Flags)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// Command returns the protocol command string for the message.  This is part
+// of the Message interface implementation.
+func (msg *MsgMerkleBlock) Command() string {
+	return cmdMerkleBlock
+}
+
+// MaxPayloadLength returns the maximum length the payload can be for the
+// receiver.  This is part of the Message interface implementation.
+func (msg *MsgMerkleBlock) MaxPayloadLength(pver uint32) uint32 {
+	return MaxBlockPayload
+}
+
+// NewMsgMerkleBlock returns a new bitcoin merkleblock message that conforms to the Message
+// interface.  See MsgMerkleBlock for details.
+func NewMsgMerkleBlock(bh *BlockHeader) *MsgMerkleBlock {
+	return &MsgMerkleBlock{
+		Header:       *bh,
+		Transactions: 0,
+		Hashes:       make([]*ShaHash, 0),
+		Flags:        make([]byte, 0),
+	}
+}

msgmerkleblock_test.go

@@ -0,0 +1,109 @@
+// Copyright (c) 2014 Conformal Systems LLC.
+// Use of this source code is governed by an ISC
+// license that can be found in the LICENSE file.
+
+package btcwire_test
+
+import (
+	"bytes"
+	"crypto/rand"
+	"github.com/conformal/btcwire"
+	"testing"
+)
+
+// TestMerkleBlock tests the MsgMerkleBlock API.
+func TestMerkleBlock(t *testing.T) {
+	pver := btcwire.ProtocolVersion
+	pverOld := btcwire.BIP0037Version - 1
+
+	// Block 1 header.
+	prevHash := &blockOne.Header.PrevBlock
+	merkleHash := &blockOne.Header.MerkleRoot
+	bits := blockOne.Header.Bits
+	nonce := blockOne.Header.Nonce
+	bh := btcwire.NewBlockHeader(prevHash, merkleHash, bits, nonce)
+
+	// Ensure the command is expected value.
+	wantCmd := "merkleblock"
+	msg := btcwire.NewMsgMerkleBlock(bh)
+	if cmd := msg.Command(); cmd != wantCmd {
+		t.Errorf("NewMsgBlock: wrong command - got %v want %v",
+			cmd, wantCmd)
+	}
+
+	// Ensure max payload is expected value for latest protocol version.
+	// Num addresses (varInt) + max allowed addresses.
+	wantPayload := uint32(1000000)
+	maxPayload := msg.MaxPayloadLength(pver)
+	if maxPayload != wantPayload {
+		t.Errorf("MaxPayloadLength: wrong max payload length for "+
+			"protocol version %d - got %v, want %v", pver,
+			maxPayload, wantPayload)
+	}
+
+	// Load maxTxPerBlock hashes
+	data := make([]byte, 32)
+	for i := 0; i < (btcwire.MaxBlockPayload/10)+1; i++ {
+		rand.Read(data)
+		hash, err := btcwire.NewShaHash(data)
+		if err != nil {
+			t.Errorf("NewShaHash failed: %v\n", err)
+			return
+		}
+
+		if err = msg.AddTxHash(hash); err != nil {
+			t.Errorf("AddTxHash failed: %v\n", err)
+			return
+		}
+	}
+
+	// Add one more Tx to test failure
+	rand.Read(data)
+	hash, err := btcwire.NewShaHash(data)
+	if err != nil {
+		t.Errorf("NewShaHash failed: %v\n", err)
+		return
+	}
+
+	if err = msg.AddTxHash(hash); err == nil {
+		t.Errorf("AddTxHash succeeded when it should have failed")
+		return
+	}
+
+	// Test encode with latest protocol version.
+	var buf bytes.Buffer
+	err = msg.BtcEncode(&buf, pver)
+	if err != nil {
+		t.Errorf("encode of MsgMerkleBlock failed %v err <%v>", msg, err)
+	}
+
+	// Test encode with old protocol version.
+	if err = msg.BtcEncode(&buf, pverOld); err == nil {
+		t.Errorf("encode of MsgMerkleBlock succeeded with old protocol " +
+			"version when it should have failed")
+		return
+	}
+
+	// Test decode with latest protocol version.
+	readmsg := btcwire.MsgMerkleBlock{}
+	err = readmsg.BtcDecode(&buf, pver)
+	if err != nil {
+		t.Errorf("decode of MsgMerkleBlock failed [%v] err <%v>", buf, err)
+	}
+
+	// Test decode with old protocol version.
+	if err = readmsg.BtcDecode(&buf, pverOld); err == nil {
+		t.Errorf("decode of MsgMerkleBlock successed with old protocol " +
+			"version when it should have failed")
+		return
+	}
+
+	// Force extra hash to test maxTxPerBlock
+	msg.Hashes = append(msg.Hashes, hash)
+	err = msg.BtcEncode(&buf, pver)
+	if err == nil {
+		t.Errorf("encode of MsgMerkleBlock succeeded with too many tx hashes " +
+			"when it should have failed")
+		return
+	}
+}