// NewFilter creates a new bloom filter instance, mainly to be used by SPV
// clients. The tweak parameter is a random value added to the seed value.
// The false positive rate is the probability of a false positive where 1.0 is
// "match everything" and zero is unachievable. Thus, providing any false
// positive rates less than 0 or greater than 1 will be adjusted to the valid
// range.
//
// For more information on what values to use for both elements and fprate,
// see https://en.wikipedia.org/wiki/Bloom_filter.
func NewFilter(elements, tweak uint32, fprate float64, flags wire.BloomUpdateType) *Filter {
// Massage the false positive rate to sane values.
if fprate > 1.0 {
fprate = 1.0
}
if fprate < 0 {
fprate = 1e-9
}
// Calculate the size of the filter in bytes for the given number of
// elements and false positive rate.
//
// Equivalent to m = -(n*ln(p) / ln(2)^2), where m is in bits.
// Then clamp it to the maximum filter size and convert to bytes.
dataLen := uint32(-1 * float64(elements) * math.Log(fprate) / ln2Squared)
dataLen = minUint32(dataLen, wire.MaxFilterLoadFilterSize*8) / 8
// Calculate the number of hash functions based on the size of the
// filter calculated above and the number of elements.
//
// Equivalent to k = (m/n) * ln(2)
// Then clamp it to the maximum allowed hash funcs.
hashFuncs := uint32(float64(dataLen*8) / float64(elements) * math.Ln2)
hashFuncs = minUint32(hashFuncs, wire.MaxFilterLoadHashFuncs)
data := make([]byte, dataLen)
msg := wire.NewMsgFilterLoad(data, hashFuncs, tweak, flags)
return &Filter{
msgFilterLoad: msg,
}
}
// TestFilterLoadMaxHashFuncsSize tests the MsgFilterLoad API maximum hash functions.
func TestFilterLoadMaxHashFuncsSize(t *testing.T) {
data := bytes.Repeat([]byte{0xff}, 10)
msg := wire.NewMsgFilterLoad(data, 61, 0, 0)
// Encode with latest protocol version.
var buf bytes.Buffer
err := msg.BtcEncode(&buf, wire.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.
readbuf := bytes.NewReader(newBuf)
err = msg.BtcDecode(readbuf, wire.ProtocolVersion)
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 := wire.NewMsgFilterLoad(data, 10, 0, 0)
// Encode with latest protocol version.
var buf bytes.Buffer
err := msg.BtcEncode(&buf, wire.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, wire.ProtocolVersion)
if err == nil {
t.Errorf("decode of MsgFilterLoad succeeded when it shouldn't "+
"have %v", msg)
}
}
// TestFilterLoadCrossProtocol tests the MsgFilterLoad API when encoding with
// the latest protocol version and decoding with BIP0031Version.
func TestFilterLoadCrossProtocol(t *testing.T) {
data := []byte{0x01, 0x02}
msg := wire.NewMsgFilterLoad(data, 10, 0, 0)
// Encode with latest protocol version.
var buf bytes.Buffer
err := msg.BtcEncode(&buf, wire.ProtocolVersion)
if err != nil {
t.Errorf("encode of NewMsgFilterLoad failed %v err <%v>", msg,
err)
}
// Decode with old protocol version.
var readmsg wire.MsgFilterLoad
err = readmsg.BtcDecode(&buf, wire.BIP0031Version)
if err == nil {
t.Errorf("decode of MsgFilterLoad succeeded when it shouldn't have %v",
msg)
}
}
// TestFilterCLearLatest tests the MsgFilterLoad API against the latest protocol
// version.
func TestFilterLoadLatest(t *testing.T) {
pver := wire.ProtocolVersion
data := []byte{0x01, 0x02}
msg := wire.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 payload is expected value for latest protocol version.
wantPayload := uint32(36012)
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 := wire.MsgFilterLoad{}
err = readmsg.BtcDecode(&buf, pver)
if err != nil {
t.Errorf("decode of MsgFilterLoad failed [%v] err <%v>", buf, err)
}
return
}
// TestMessage tests the Read/WriteMessage and Read/WriteMessageN API.
func TestMessage(t *testing.T) {
pver := wire.ProtocolVersion
// Create the various types of messages to test.
// MsgVersion.
addrYou := &net.TCPAddr{IP: net.ParseIP("192.168.0.1"), Port: 8333}
you, err := wire.NewNetAddress(addrYou, wire.SFNodeNetwork)
if err != nil {
t.Errorf("NewNetAddress: %v", err)
}
you.Timestamp = time.Time{} // Version message has zero value timestamp.
addrMe := &net.TCPAddr{IP: net.ParseIP("127.0.0.1"), Port: 8333}
me, err := wire.NewNetAddress(addrMe, wire.SFNodeNetwork)
if err != nil {
t.Errorf("NewNetAddress: %v", err)
}
me.Timestamp = time.Time{} // Version message has zero value timestamp.
msgVersion := wire.NewMsgVersion(me, you, 123123, 0)
msgVerack := wire.NewMsgVerAck()
msgGetAddr := wire.NewMsgGetAddr()
msgAddr := wire.NewMsgAddr()
msgGetBlocks := wire.NewMsgGetBlocks(&wire.ShaHash{})
msgBlock := &blockOne
msgInv := wire.NewMsgInv()
msgGetData := wire.NewMsgGetData()
msgNotFound := wire.NewMsgNotFound()
msgTx := wire.NewMsgTx()
msgPing := wire.NewMsgPing(123123)
msgPong := wire.NewMsgPong(123123)
msgGetHeaders := wire.NewMsgGetHeaders()
msgHeaders := wire.NewMsgHeaders()
msgAlert := wire.NewMsgAlert([]byte("payload"), []byte("signature"))
msgMemPool := wire.NewMsgMemPool()
msgFilterAdd := wire.NewMsgFilterAdd([]byte{0x01})
msgFilterClear := wire.NewMsgFilterClear()
msgFilterLoad := wire.NewMsgFilterLoad([]byte{0x01}, 10, 0, wire.BloomUpdateNone)
bh := wire.NewBlockHeader(&wire.ShaHash{}, &wire.ShaHash{}, 0, 0)
msgMerkleBlock := wire.NewMsgMerkleBlock(bh)
msgReject := wire.NewMsgReject("block", wire.RejectDuplicate, "duplicate block")
tests := []struct {
in wire.Message // Value to encode
out wire.Message // Expected decoded value
pver uint32 // Protocol version for wire encoding
btcnet wire.BitcoinNet // Network to use for wire encoding
bytes int // Expected num bytes read/written
}{
{msgVersion, msgVersion, pver, wire.MainNet, 125},
{msgVerack, msgVerack, pver, wire.MainNet, 24},
{msgGetAddr, msgGetAddr, pver, wire.MainNet, 24},
{msgAddr, msgAddr, pver, wire.MainNet, 25},
{msgGetBlocks, msgGetBlocks, pver, wire.MainNet, 61},
{msgBlock, msgBlock, pver, wire.MainNet, 239},
{msgInv, msgInv, pver, wire.MainNet, 25},
{msgGetData, msgGetData, pver, wire.MainNet, 25},
{msgNotFound, msgNotFound, pver, wire.MainNet, 25},
{msgTx, msgTx, pver, wire.MainNet, 34},
{msgPing, msgPing, pver, wire.MainNet, 32},
{msgPong, msgPong, pver, wire.MainNet, 32},
{msgGetHeaders, msgGetHeaders, pver, wire.MainNet, 61},
{msgHeaders, msgHeaders, pver, wire.MainNet, 25},
{msgAlert, msgAlert, pver, wire.MainNet, 42},
{msgMemPool, msgMemPool, pver, wire.MainNet, 24},
{msgFilterAdd, msgFilterAdd, pver, wire.MainNet, 26},
{msgFilterClear, msgFilterClear, pver, wire.MainNet, 24},
{msgFilterLoad, msgFilterLoad, pver, wire.MainNet, 35},
{msgMerkleBlock, msgMerkleBlock, pver, wire.MainNet, 110},
{msgReject, msgReject, pver, wire.MainNet, 79},
}
t.Logf("Running %d tests", len(tests))
for i, test := range tests {
// Encode to wire format.
var buf bytes.Buffer
nw, err := wire.WriteMessageN(&buf, test.in, test.pver, test.btcnet)
if err != nil {
t.Errorf("WriteMessage #%d error %v", i, err)
continue
}
// Ensure the number of bytes written match the expected value.
if nw != test.bytes {
t.Errorf("WriteMessage #%d unexpected num bytes "+
"written - got %d, want %d", i, nw, test.bytes)
}
// Decode from wire format.
rbuf := bytes.NewReader(buf.Bytes())
nr, msg, _, err := wire.ReadMessageN(rbuf, test.pver, test.btcnet)
if err != nil {
t.Errorf("ReadMessage #%d error %v, msg %v", i, err,
spew.Sdump(msg))
continue
}
if !reflect.DeepEqual(msg, test.out) {
t.Errorf("ReadMessage #%d\n got: %v want: %v", i,
spew.Sdump(msg), spew.Sdump(test.out))
continue
}
// Ensure the number of bytes read match the expected value.
if nr != test.bytes {
t.Errorf("ReadMessage #%d unexpected num bytes read - "+
"got %d, want %d", i, nr, test.bytes)
}
}
// Do the same thing for Read/WriteMessage, but ignore the bytes since
// they don't return them.
t.Logf("Running %d tests", len(tests))
for i, test := range tests {
// Encode to wire format.
var buf bytes.Buffer
err := wire.WriteMessage(&buf, test.in, test.pver, test.btcnet)
if err != nil {
t.Errorf("WriteMessage #%d error %v", i, err)
continue
}
// Decode from wire format.
rbuf := bytes.NewReader(buf.Bytes())
msg, _, err := wire.ReadMessage(rbuf, test.pver, test.btcnet)
if err != nil {
t.Errorf("ReadMessage #%d error %v, msg %v", i, err,
spew.Sdump(msg))
continue
}
if !reflect.DeepEqual(msg, test.out) {
t.Errorf("ReadMessage #%d\n got: %v want: %v", i,
spew.Sdump(msg), spew.Sdump(test.out))
continue
}
}
}
// TestFilterLoadWireErrors performs negative tests against wire encode and decode
// of MsgFilterLoad to confirm error paths work correctly.
func TestFilterLoadWireErrors(t *testing.T) {
pver := wire.ProtocolVersion
pverNoFilterLoad := wire.BIP0037Version - 1
wireErr := &wire.MessageError{}
baseFilter := []byte{0x01, 0x02, 0x03, 0x04}
baseFilterLoad := wire.NewMsgFilterLoad(baseFilter, 10, 0,
wire.BloomUpdateNone)
baseFilterLoadEncoded := append([]byte{0x04}, baseFilter...)
baseFilterLoadEncoded = append(baseFilterLoadEncoded,
0x00, 0x00, 0x00, 0x0a, // HashFuncs
0x00, 0x00, 0x00, 0x00, // Tweak
0x00) // Flags
tests := []struct {
in *wire.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.
// Force error in filter size.
{
baseFilterLoad, baseFilterLoadEncoded, pver, 0,
io.ErrShortWrite, io.EOF,
},
// Force error in filter.
{
baseFilterLoad, baseFilterLoadEncoded, pver, 1,
io.ErrShortWrite, io.EOF,
},
// Force error in hash funcs.
{
baseFilterLoad, baseFilterLoadEncoded, pver, 5,
io.ErrShortWrite, io.EOF,
},
// Force error in tweak.
{
baseFilterLoad, baseFilterLoadEncoded, pver, 9,
io.ErrShortWrite, io.EOF,
},
// Force error in flags.
{
baseFilterLoad, baseFilterLoadEncoded, pver, 13,
io.ErrShortWrite, io.EOF,
},
// Force error due to unsupported protocol version.
{
baseFilterLoad, baseFilterLoadEncoded, pverNoFilterLoad,
10, wireErr, wireErr,
},
}
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 reflect.TypeOf(err) != reflect.TypeOf(test.writeErr) {
t.Errorf("BtcEncode #%d wrong error got: %v, want: %v",
i, err, test.writeErr)
continue
}
// For errors which are not of type wire.MessageError, check
// them for equality.
if _, ok := err.(*wire.MessageError); !ok {
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 wire.MsgFilterLoad
r := newFixedReader(test.max, test.buf)
err = msg.BtcDecode(r, test.pver)
if reflect.TypeOf(err) != reflect.TypeOf(test.readErr) {
t.Errorf("BtcDecode #%d wrong error got: %v, want: %v",
i, err, test.readErr)
continue
}
// For errors which are not of type wire.MessageError, check
// them for equality.
if _, ok := err.(*wire.MessageError); !ok {
if err != test.readErr {
t.Errorf("BtcDecode #%d wrong error got: %v, "+
"want: %v", i, err, test.readErr)
continue
}
}
}
}