// 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.
readbuf := bytes.NewReader(newBuf)
err = msg.BtcDecode(readbuf, btcwire.ProtocolVersion)
if err == nil {
t.Errorf("decode of MsgFilterLoad succeeded when it shouldn't have %v",
msg)
}
}
// 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 btcwire.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, btcwire.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, btcwire.MaxFilterLoadHashFuncs)
data := make([]byte, dataLen)
msg := btcwire.NewMsgFilterLoad(data, hashFuncs, tweak, flags)
return &Filter{
msgFilterLoad: 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)
}
}
// 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 := 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 NewMsgFilterLoad failed %v err <%v>", msg,
err)
}
// Decode with old protocol version.
var 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)
}
}
// 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 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 := btcwire.MsgFilterLoad{}
err = readmsg.BtcDecode(&buf, pver)
if err != nil {
t.Errorf("decode of MsgFilterLoad failed [%v] err <%v>", buf, err)
}
return
}
// 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
pverNoFilterLoad := btcwire.BIP0037Version - 1
btcwireErr := &btcwire.MessageError{}
baseFilter := []byte{0x01, 0x02, 0x03, 0x04}
baseFilterLoad := btcwire.NewMsgFilterLoad(baseFilter, 10, 0,
btcwire.BloomUpdateNone)
baseFilterLoadEncoded := append([]byte{0x04}, baseFilter...)
baseFilterLoadEncoded = append(baseFilterLoadEncoded,
0x00, 0x00, 0x00, 0x0a, // HashFuncs
0x00, 0x00, 0x00, 0x00, // Tweak
0x00) // Flags
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.
// 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, btcwireErr, btcwireErr,
},
}
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 btcwire.MessageError, check
// them for equality.
if _, ok := err.(*btcwire.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 btcwire.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 btcwire.MessageError, check
// them for equality.
if _, ok := err.(*btcwire.MessageError); !ok {
if err != test.readErr {
t.Errorf("BtcDecode #%d wrong error got: %v, "+
"want: %v", i, err, test.readErr)
continue
}
}
}
}