multi: change cfilter Extended bool to FilterType uint8

The cfilter BIP specifies that the filter type is a uint8. The
current code encodes it correctly on the wire, but everywhere else,
it's treated as a boolean (false for basic filter, true for
extended). This commit corrects that to account for possible
additional filter types in the future. All package changes are
done in one commit as they're all interdependent. The following
packages are updated:

* blockchain/indexers
* btcjson
* peer
* wire
* main (server.go and rpcserver.go)

blockchain/indexers/cfindex.go

@@ -30,21 +30,21 @@ var (
 	// the index. The rest of the buckets live below this bucket.
 	cfIndexParentBucketKey = []byte("cfindexparentbucket")
 
-	// cfBasicIndexKey is the name of the db bucket used to house the
+	// cfIndexKeys is an array of db bucket names used to house indexes of
-	// block hash -> basic cf index (cf#0).
+	// block hashes to cfilters.
-	cfBasicIndexKey = []byte("cf0byhashidx")
+	cfIndexKeys = [][]byte{
+		[]byte("cf0byhashidx"),
+		[]byte("cf1byhashidx"),
+	}
 
-	// cfBasicHeaderKey is the name of the db bucket used to house the
+	// cfHeaderKeys is an array of db bucket names used to house indexes of
-	// block hash -> basic cf header index (cf#0).
+	// block hashes to cf headers.
-	cfBasicHeaderKey = []byte("cf0headerbyhashidx")
+	cfHeaderKeys = [][]byte{
+		[]byte("cf0headerbyhashidx"),
+		[]byte("cf1headerbyhashidx"),
+	}
 
-	// cfExtendedIndexKey is the name of the db bucket used to house the
+	maxFilterType = uint8(len(cfHeaderKeys) - 1)
-	// block hash -> extended cf index (cf#1).
-	cfExtendedIndexKey = []byte("cf1byhashidx")
-
-	// cfExtendedHeaderKey is the name of the db bucket used to house the
-	// block hash -> extended cf header index (cf#1).
-	cfExtendedHeaderKey = []byte("cf1headerbyhashidx")
 )
 
 // dbFetchFilter retrieves a block's basic or extended filter. A filter's
@@ -131,27 +131,25 @@ func (idx *CfIndex) Create(dbTx database.Tx) error {
 	if err != nil {
 		return err
 	}
-	_, err = cfIndexParentBucket.CreateBucket(cfBasicIndexKey)
+
+	for _, bucketName := range cfIndexKeys {
+		_, err = cfIndexParentBucket.CreateBucket(bucketName)
 		if err != nil {
 			return err
 		}
-	_, err = cfIndexParentBucket.CreateBucket(cfBasicHeaderKey)
+	}
+
+	for _, bucketName := range cfHeaderKeys {
+		_, err = cfIndexParentBucket.CreateBucket(bucketName)
 		if err != nil {
 			return err
 		}
-	_, err = cfIndexParentBucket.CreateBucket(cfExtendedIndexKey)
-	if err != nil {
-		return err
-	}
-	_, err = cfIndexParentBucket.CreateBucket(cfExtendedHeaderKey)
-	if err != nil {
-		return err
 	}
 
 	firstHeader := make([]byte, chainhash.HashSize)
 	err = dbStoreFilterHeader(
 		dbTx,
-		cfBasicHeaderKey,
+		cfHeaderKeys[0],
 		&idx.chainParams.GenesisBlock.Header.PrevBlock,
 		firstHeader,
 	)
@@ -161,7 +159,7 @@ func (idx *CfIndex) Create(dbTx database.Tx) error {
 
 	return dbStoreFilterHeader(
 		dbTx,
-		cfExtendedHeaderKey,
+		cfHeaderKeys[1],
 		&idx.chainParams.GenesisBlock.Header.PrevBlock,
 		firstHeader,
 	)
@@ -170,15 +168,14 @@ func (idx *CfIndex) Create(dbTx database.Tx) error {
 // storeFilter stores a given filter, and performs the steps needed to
 // generate the filter's header.
 func storeFilter(dbTx database.Tx, block *btcutil.Block, f *gcs.Filter,
-	extended bool) error {
+	filterType uint8) error {
+	if filterType > maxFilterType {
+		return errors.New("unsupported filter type")
+	}
 
 	// Figure out which buckets to use.
-	fkey := cfBasicIndexKey
+	fkey := cfIndexKeys[filterType]
-	hkey := cfBasicHeaderKey
+	hkey := cfHeaderKeys[filterType]
-	if extended {
-		fkey = cfExtendedIndexKey
-		hkey = cfExtendedHeaderKey
-	}
 
 	// Start by storing the filter.
 	h := block.Hash()
@@ -218,7 +215,7 @@ func (idx *CfIndex) ConnectBlock(dbTx database.Tx, block *btcutil.Block,
 		return err
 	}
 
-	if err := storeFilter(dbTx, block, f, false); err != nil {
+	if err := storeFilter(dbTx, block, f, 0); err != nil {
 		return err
 	}
 
@@ -227,7 +224,7 @@ func (idx *CfIndex) ConnectBlock(dbTx database.Tx, block *btcutil.Block,
 		return err
 	}
 
-	return storeFilter(dbTx, block, f, true)
+	return storeFilter(dbTx, block, f, 1)
 }
 
 // DisconnectBlock is invoked by the index manager when a block has been
@@ -236,26 +233,34 @@ func (idx *CfIndex) ConnectBlock(dbTx database.Tx, block *btcutil.Block,
 func (idx *CfIndex) DisconnectBlock(dbTx database.Tx, block *btcutil.Block,
 	view *blockchain.UtxoViewpoint) error {
 
-	err := dbDeleteFilter(dbTx, cfBasicIndexKey, block.Hash())
+	for _, key := range cfIndexKeys {
+		err := dbDeleteFilter(dbTx, key, block.Hash())
 		if err != nil {
 			return err
 		}
+	}
 
-	return dbDeleteFilter(dbTx, cfExtendedIndexKey, block.Hash())
+	for _, key := range cfHeaderKeys {
+		err := dbDeleteFilterHeader(dbTx, key, block.Hash())
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
 }
 
 // FilterByBlockHash returns the serialized contents of a block's basic or
 // extended committed filter.
-func (idx *CfIndex) FilterByBlockHash(h *chainhash.Hash, extended bool) ([]byte, error) {
+func (idx *CfIndex) FilterByBlockHash(h *chainhash.Hash, filterType uint8) ([]byte, error) {
 	var f []byte
 	err := idx.db.View(func(dbTx database.Tx) error {
-		var err error
+		if filterType > maxFilterType {
-		key := cfBasicIndexKey
+			return errors.New("unsupported filter type")
-		if extended {
-			key = cfExtendedIndexKey
 		}
 
-		f, err = dbFetchFilter(dbTx, key, h)
+		var err error
+		f, err = dbFetchFilter(dbTx, cfIndexKeys[filterType], h)
 		return err
 	})
 	return f, err
@@ -263,16 +268,15 @@ func (idx *CfIndex) FilterByBlockHash(h *chainhash.Hash, extended bool) ([]byte,
 
 // FilterHeaderByBlockHash returns the serialized contents of a block's basic
 // or extended committed filter header.
-func (idx *CfIndex) FilterHeaderByBlockHash(h *chainhash.Hash, extended bool) ([]byte, error) {
+func (idx *CfIndex) FilterHeaderByBlockHash(h *chainhash.Hash, filterType uint8) ([]byte, error) {
 	var fh []byte
 	err := idx.db.View(func(dbTx database.Tx) error {
-		var err error
+		if filterType > 1 {
-		key := cfBasicHeaderKey
+			return errors.New("unsupported filter type")
-		if extended {
-			key = cfExtendedHeaderKey
 		}
 
-		fh, err = dbFetchFilterHeader(dbTx, key, h)
+		var err error
+		fh, err = dbFetchFilterHeader(dbTx, cfHeaderKeys[filterType], h)
 		return err
 	})
 	return fh, err

btcjson/chainsvrcmds.go

@@ -278,33 +278,34 @@ func NewGetBlockTemplateCmd(request *TemplateRequest) *GetBlockTemplateCmd {
 		Request: request,
 	}
 }
+
 // GetCFilterCmd defines the getcfilter JSON-RPC command.
 type GetCFilterCmd struct {
 	Hash       string
-	Extended bool
+	FilterType uint8
 }
 
 // NewGetCFilterCmd returns a new instance which can be used to issue a
 // getcfilter JSON-RPC command.
-func NewGetCFilterCmd(hash string, extended bool) *GetCFilterCmd {
+func NewGetCFilterCmd(hash string, filterType uint8) *GetCFilterCmd {
 	return &GetCFilterCmd{
 		Hash:       hash,
-		Extended: extended,
+		FilterType: filterType,
 	}
 }
 
 // GetCFilterHeaderCmd defines the getcfilterheader JSON-RPC command.
 type GetCFilterHeaderCmd struct {
 	Hash       string
-	Extended bool
+	FilterType uint8
 }
 
 // NewGetCFilterHeaderCmd returns a new instance which can be used to issue a
 // getcfilterheader JSON-RPC command.
-func NewGetCFilterHeaderCmd(hash string, extended bool) *GetCFilterHeaderCmd {
+func NewGetCFilterHeaderCmd(hash string, filterType uint8) *GetCFilterHeaderCmd {
 	return &GetCFilterHeaderCmd{
 		Hash:       hash,
-		Extended: extended,
+		FilterType: filterType,
 	}
 }
 

btcjson/chainsvrcmds_test.go

@@ -320,10 +320,10 @@ func TestChainSvrCmds(t *testing.T) {
 		{
 			name: "getcfilter",
 			newCmd: func() (interface{}, error) {
-				return btcjson.NewCmd("getcfilter", "123", false)
+				return btcjson.NewCmd("getcfilter", "123", 0)
 			},
 			staticCmd: func() interface{} {
-				return btcjson.NewGetCFilterCmd("123", false)
+				return btcjson.NewGetCFilterCmd("123", 0)
 			},
 			marshalled: `{"jsonrpc":"1.0","method":"getcfilter","params":["123",false],"id":1}`,
 			unmarshalled: &btcjson.GetCFilterCmd{
@@ -333,10 +333,10 @@ func TestChainSvrCmds(t *testing.T) {
 		{
 			name: "getcfilterheader",
 			newCmd: func() (interface{}, error) {
-				return btcjson.NewCmd("getcfilterheader", "123", false)
+				return btcjson.NewCmd("getcfilterheader", "123", 0)
 			},
 			staticCmd: func() interface{} {
-				return btcjson.NewGetCFilterHeaderCmd("123", false)
+				return btcjson.NewGetCFilterHeaderCmd("123", 0)
 			},
 			marshalled: `{"jsonrpc":"1.0","method":"getcfilterheader","params":["123",false],"id":1}`,
 			unmarshalled: &btcjson.GetCFilterHeaderCmd{

peer/peer_test.go

@@ -536,7 +536,7 @@ func TestPeerListeners(t *testing.T) {
 		},
 		{
 			"OnGetCFilter",
-			wire.NewMsgGetCFilter(&chainhash.Hash{}, false),
+			wire.NewMsgGetCFilter(&chainhash.Hash{}, 0),
 		},
 		{
 			"OnGetCFHeaders",
@@ -544,7 +544,7 @@ func TestPeerListeners(t *testing.T) {
 		},
 		{
 			"OnCFilter",
-			wire.NewMsgCFilter(&chainhash.Hash{}, true,
+			wire.NewMsgCFilter(&chainhash.Hash{}, 1,
 				[]byte("payload")),
 		},
 		{

rpcserver.go

@@ -2163,7 +2163,7 @@ func handleGetCFilter(s *rpcServer, cmd interface{}, closeChan <-chan struct{})
 		return nil, rpcDecodeHexError(c.Hash)
 	}
 
-	filterBytes, err := s.cfg.CfIndex.FilterByBlockHash(hash, c.Extended)
+	filterBytes, err := s.cfg.CfIndex.FilterByBlockHash(hash, c.FilterType)
 	if err != nil {
 		rpcsLog.Debugf("Could not find committed filter for %v: %v",
 			hash, err)
@@ -2192,7 +2192,7 @@ func handleGetCFilterHeader(s *rpcServer, cmd interface{}, closeChan <-chan stru
 		return nil, rpcDecodeHexError(c.Hash)
 	}
 
-	headerBytes, err := s.cfg.CfIndex.FilterHeaderByBlockHash(hash, c.Extended)
+	headerBytes, err := s.cfg.CfIndex.FilterHeaderByBlockHash(hash, c.FilterType)
 	if len(headerBytes) > 0 {
 		rpcsLog.Debugf("Found header of committed filter for %v", hash)
 	} else {

server.go

@@ -747,7 +747,7 @@ func (sp *serverPeer) OnGetCFilter(_ *peer.Peer, msg *wire.MsgGetCFilter) {
 	}
 
 	filterBytes, err := sp.server.cfIndex.FilterByBlockHash(&msg.BlockHash,
-		msg.Extended)
+		msg.FilterType)
 
 	if len(filterBytes) > 0 {
 		peerLog.Tracef("Obtained CF for %v", msg.BlockHash)
@@ -756,7 +756,7 @@ func (sp *serverPeer) OnGetCFilter(_ *peer.Peer, msg *wire.MsgGetCFilter) {
 			err)
 	}
 
-	filterMsg := wire.NewMsgCFilter(&msg.BlockHash, msg.Extended,
+	filterMsg := wire.NewMsgCFilter(&msg.BlockHash, msg.FilterType,
 		filterBytes)
 	sp.QueueMessage(filterMsg, nil)
 }
@@ -789,7 +789,7 @@ func (sp *serverPeer) OnGetCFHeaders(_ *peer.Peer, msg *wire.MsgGetCFHeaders) {
 		// Fetch the raw committed filter header bytes from the
 		// database.
 		headerBytes, err := sp.server.cfIndex.FilterHeaderByBlockHash(
-			&msg.HashStop, msg.Extended)
+			&msg.HashStop, msg.FilterType)
 		if (err != nil) || (len(headerBytes) == 0) {
 			peerLog.Warnf("Could not obtain CF header for %v: %v",
 				msg.HashStop, err)
@@ -808,7 +808,7 @@ func (sp *serverPeer) OnGetCFHeaders(_ *peer.Peer, msg *wire.MsgGetCFHeaders) {
 		headersMsg := wire.NewMsgCFHeaders()
 		headersMsg.AddCFHeader(&header)
 		headersMsg.StopHash = msg.HashStop
-		headersMsg.Extended = msg.Extended
+		headersMsg.FilterType = msg.FilterType
 		sp.QueueMessage(headersMsg, nil)
 		return
 	}
@@ -849,7 +849,7 @@ func (sp *serverPeer) OnGetCFHeaders(_ *peer.Peer, msg *wire.MsgGetCFHeaders) {
 		// Fetch the raw committed filter header bytes from the
 		// database.
 		headerBytes, err := sp.server.cfIndex.FilterHeaderByBlockHash(
-			&hashList[i], msg.Extended)
+			&hashList[i], msg.FilterType)
 		if (err != nil) || (len(headerBytes) == 0) {
 			peerLog.Warnf("Could not obtain CF header for %v: %v",
 				hashList[i], err)
@@ -868,7 +868,7 @@ func (sp *serverPeer) OnGetCFHeaders(_ *peer.Peer, msg *wire.MsgGetCFHeaders) {
 		headersMsg.AddCFHeader(&header)
 	}
 
-	headersMsg.Extended = msg.Extended
+	headersMsg.FilterType = msg.FilterType
 	headersMsg.StopHash = hashList[len(hashList)-1]
 	sp.QueueMessage(headersMsg, nil)
 }

wire/message_test.go

@@ -69,9 +69,9 @@ func TestMessage(t *testing.T) {
 	bh := NewBlockHeader(1, &chainhash.Hash{}, &chainhash.Hash{}, 0, 0)
 	msgMerkleBlock := NewMsgMerkleBlock(bh)
 	msgReject := NewMsgReject("block", RejectDuplicate, "duplicate block")
-	msgGetCFilter := NewMsgGetCFilter(&chainhash.Hash{}, false)
+	msgGetCFilter := NewMsgGetCFilter(&chainhash.Hash{}, 0)
 	msgGetCFHeaders := NewMsgGetCFHeaders()
-	msgCFilter := NewMsgCFilter(&chainhash.Hash{}, true, []byte("payload"))
+	msgCFilter := NewMsgCFilter(&chainhash.Hash{}, 1, []byte("payload"))
 	msgCFHeaders := NewMsgCFHeaders()
 
 	tests := []struct {

wire/msgcfheaders.go

@@ -28,7 +28,7 @@ const (
 // MsgGetCFHeaders for details on requesting the headers.
 type MsgCFHeaders struct {
 	StopHash     chainhash.Hash
-	Extended     bool
+	FilterType   uint8
 	HeaderHashes []*chainhash.Hash
 }
 
@@ -53,8 +53,8 @@ func (msg *MsgCFHeaders) BtcDecode(r io.Reader, pver uint32, _ MessageEncoding)
 		return err
 	}
 
-	// Read extended flag
+	// Read filter type
-	err = readElement(r, &msg.Extended)
+	err = readElement(r, &msg.FilterType)
 	if err != nil {
 		return err
 	}
@@ -97,8 +97,8 @@ func (msg *MsgCFHeaders) BtcEncode(w io.Writer, pver uint32, _ MessageEncoding)
 		return err
 	}
 
-	// Write extended flag
+	// Write filter type
-	err = writeElement(w, msg.Extended)
+	err = writeElement(w, msg.FilterType)
 	if err != nil {
 		return err
 	}

wire/msgcfilter.go

@@ -18,7 +18,7 @@ const (
 
 type MsgCFilter struct {
 	BlockHash  chainhash.Hash
-	Extended  bool
+	FilterType uint8
 	Data       []byte
 }
 
@@ -31,8 +31,8 @@ func (msg *MsgCFilter) BtcDecode(r io.Reader, pver uint32, _ MessageEncoding) er
 	if err != nil {
 		return err
 	}
-	// Read extended flag
+	// Read filter type
-	err = readElement(r, &msg.Extended)
+	err = readElement(r, &msg.FilterType)
 	if err != nil {
 		return err
 	}
@@ -57,7 +57,7 @@ func (msg *MsgCFilter) BtcEncode(w io.Writer, pver uint32, _ MessageEncoding) er
 		return err
 	}
 
-	err = writeElement(w, msg.Extended)
+	err = writeElement(w, msg.FilterType)
 	if err != nil {
 		return err
 	}
@@ -96,11 +96,11 @@ func (msg *MsgCFilter) MaxPayloadLength(pver uint32) uint32 {
 
 // NewMsgCFilter returns a new bitcoin cfilter message that conforms to the
 // Message interface. See MsgCFilter for details.
-func NewMsgCFilter(blockHash *chainhash.Hash, extended bool,
+func NewMsgCFilter(blockHash *chainhash.Hash, filterType uint8,
 	data []byte) *MsgCFilter {
 	return &MsgCFilter{
 		BlockHash:  *blockHash,
-		Extended:  extended,
+		FilterType: filterType,
 		Data:       data,
 	}
 }

wire/msggetcfheaders.go

@@ -12,13 +12,13 @@ import (
 )
 
 // MsgGetCFHeaders is a message similar to MsgGetHeaders, but for committed
-// filter headers. It allows to set the Extended field to get headers in the
+// filter headers. It allows to set the FilterType field to get headers in the
-// chain of basic (false) or extended (true) headers.
+// chain of basic (0x00) or extended (0x01) headers.
 type MsgGetCFHeaders struct {
 	ProtocolVersion    uint32
 	BlockLocatorHashes []*chainhash.Hash
 	HashStop           chainhash.Hash
-	Extended           bool
+	FilterType         uint8
 }
 
 // AddBlockLocatorHash adds a new block locator hash to the message.
@@ -70,7 +70,7 @@ func (msg *MsgGetCFHeaders) BtcDecode(r io.Reader, pver uint32, _ MessageEncodin
 		return err
 	}
 
-	return readElement(r, &msg.Extended)
+	return readElement(r, &msg.FilterType)
 }
 
 // BtcEncode encodes the receiver to w using the bitcoin protocol encoding.
@@ -106,7 +106,7 @@ func (msg *MsgGetCFHeaders) BtcEncode(w io.Writer, pver uint32, _ MessageEncodin
 		return err
 	}
 
-	return writeElement(w, msg.Extended)
+	return writeElement(w, msg.FilterType)
 }
 
 // Command returns the protocol command string for the message.  This is part
@@ -119,7 +119,7 @@ func (msg *MsgGetCFHeaders) Command() string {
 // receiver.  This is part of the Message interface implementation.
 func (msg *MsgGetCFHeaders) MaxPayloadLength(pver uint32) uint32 {
 	// Version 4 bytes + num block locator hashes (varInt) + max allowed
-	// block locators + hash stop + Extended flag 1 byte.
+	// block locators + hash stop + filter type 1 byte.
 	return 4 + MaxVarIntPayload + (MaxBlockLocatorsPerMsg *
 		chainhash.HashSize) + chainhash.HashSize + 1
 }

wire/msggetcfilter.go

@@ -12,7 +12,7 @@ import (
 
 type MsgGetCFilter struct {
 	BlockHash  chainhash.Hash
-	Extended  bool
+	FilterType uint8
 }
 
 func (msg *MsgGetCFilter) BtcDecode(r io.Reader, pver uint32, _ MessageEncoding) error {
@@ -20,7 +20,7 @@ func (msg *MsgGetCFilter) BtcDecode(r io.Reader, pver uint32, _ MessageEncoding)
 	if err != nil {
 		return err
 	}
-	return readElement(r, &msg.Extended)
+	return readElement(r, &msg.FilterType)
 }
 
 // BtcEncode encodes the receiver to w using the bitcoin protocol encoding.
@@ -30,7 +30,7 @@ func (msg *MsgGetCFilter) BtcEncode(w io.Writer, pver uint32, _ MessageEncoding)
 	if err != nil {
 		return err
 	}
-	return writeElement(w, msg.Extended)
+	return writeElement(w, msg.FilterType)
 }
 
 // Command returns the protocol command string for the message.  This is part
@@ -42,16 +42,16 @@ func (msg *MsgGetCFilter) Command() string {
 // MaxPayloadLength returns the maximum length the payload can be for the
 // receiver.  This is part of the Message interface implementation.
 func (msg *MsgGetCFilter) MaxPayloadLength(pver uint32) uint32 {
-	// Block hash + Extended flag.
+	// Block hash + filter type.
 	return chainhash.HashSize + 1
 }
 
 // NewMsgGetCFilter returns a new bitcoin getcfilter message that conforms to
 // the Message interface using the passed parameters and defaults for the
 // remaining fields.
-func NewMsgGetCFilter(blockHash *chainhash.Hash, extended bool) *MsgGetCFilter {
+func NewMsgGetCFilter(blockHash *chainhash.Hash, filterType uint8) *MsgGetCFilter {
 	return &MsgGetCFilter{
 		BlockHash:  *blockHash,
-		Extended:  extended,
+		FilterType: filterType,
 	}
 }