whisper/whisperv6: implement pow/bloom exchange protocol (#15802)

This is the main feature of v6.
This commit is contained in:
gluk256 2018-01-12 13:11:22 +02:00 committed by Felix Lange
parent 56152b31ac
commit fd869dc839
7 changed files with 452 additions and 76 deletions

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@ -116,12 +116,17 @@ func (api *PublicWhisperAPI) SetMaxMessageSize(ctx context.Context, size uint32)
return true, api.w.SetMaxMessageSize(size)
}
// SetMinPow sets the minimum PoW for a message before it is accepted.
// SetMinPow sets the minimum PoW, and notifies the peers.
func (api *PublicWhisperAPI) SetMinPoW(ctx context.Context, pow float64) (bool, error) {
return true, api.w.SetMinimumPoW(pow)
}
// MarkTrustedPeer marks a peer trusted. , which will allow it to send historic (expired) messages.
// SetBloomFilter sets the new value of bloom filter, and notifies the peers.
func (api *PublicWhisperAPI) SetBloomFilter(ctx context.Context, bloom hexutil.Bytes) (bool, error) {
return true, api.w.SetBloomFilter(bloom)
}
// MarkTrustedPeer marks a peer trusted, which will allow it to send historic (expired) messages.
// Note: This function is not adding new nodes, the node needs to exists as a peer.
func (api *PublicWhisperAPI) MarkTrustedPeer(ctx context.Context, enode string) (bool, error) {
n, err := discover.ParseNode(enode)

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@ -35,7 +35,6 @@ import (
)
const (
EnvelopeVersion = uint64(0)
ProtocolVersion = uint64(6)
ProtocolVersionStr = "6.0"
ProtocolName = "shh"
@ -52,11 +51,14 @@ const (
paddingMask = byte(3)
signatureFlag = byte(4)
TopicLength = 4
signatureLength = 65
aesKeyLength = 32
AESNonceLength = 12
keyIdSize = 32
TopicLength = 4 // in bytes
signatureLength = 65 // in bytes
aesKeyLength = 32 // in bytes
AESNonceLength = 12 // in bytes
keyIdSize = 32 // in bytes
bloomFilterSize = 64 // in bytes
EnvelopeHeaderLength = 20
MaxMessageSize = uint32(10 * 1024 * 1024) // maximum accepted size of a message.
DefaultMaxMessageSize = uint32(1024 * 1024)
@ -68,10 +70,8 @@ const (
expirationCycle = time.Second
transmissionCycle = 300 * time.Millisecond
DefaultTTL = 50 // seconds
SynchAllowance = 10 // seconds
EnvelopeHeaderLength = 20
DefaultTTL = 50 // seconds
DefaultSyncAllowance = 10 // seconds
)
type unknownVersionError uint64

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@ -42,9 +42,11 @@ type Envelope struct {
Data []byte
Nonce uint64
pow float64 // Message-specific PoW as described in the Whisper specification.
hash common.Hash // Cached hash of the envelope to avoid rehashing every time.
// Don't access hash directly, use Hash() function instead.
pow float64 // Message-specific PoW as described in the Whisper specification.
// the following variables should not be accessed directly, use the corresponding function instead: Hash(), Bloom()
hash common.Hash // Cached hash of the envelope to avoid rehashing every time.
bloom []byte
}
// size returns the size of envelope as it is sent (i.e. public fields only)
@ -227,3 +229,30 @@ func (e *Envelope) Open(watcher *Filter) (msg *ReceivedMessage) {
}
return msg
}
// Bloom maps 4-bytes Topic into 64-byte bloom filter with 3 bits set (at most).
func (e *Envelope) Bloom() []byte {
if e.bloom == nil {
e.bloom = TopicToBloom(e.Topic)
}
return e.bloom
}
// TopicToBloom converts the topic (4 bytes) to the bloom filter (64 bytes)
func TopicToBloom(topic TopicType) []byte {
b := make([]byte, bloomFilterSize)
var index [3]int
for j := 0; j < 3; j++ {
index[j] = int(topic[j])
if (topic[3] & (1 << uint(j))) != 0 {
index[j] += 256
}
}
for j := 0; j < 3; j++ {
byteIndex := index[j] / 8
bitIndex := index[j] % 8
b[byteIndex] = (1 << uint(bitIndex))
}
return b
}

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@ -36,6 +36,7 @@ type Peer struct {
trusted bool
powRequirement float64
bloomFilter []byte // may contain nil in case of full node
known *set.Set // Messages already known by the peer to avoid wasting bandwidth
@ -74,8 +75,12 @@ func (p *Peer) handshake() error {
// Send the handshake status message asynchronously
errc := make(chan error, 1)
go func() {
errc <- p2p.Send(p.ws, statusCode, ProtocolVersion)
pow := p.host.MinPow()
powConverted := math.Float64bits(pow)
bloom := p.host.BloomFilter()
errc <- p2p.SendItems(p.ws, statusCode, ProtocolVersion, powConverted, bloom)
}()
// Fetch the remote status packet and verify protocol match
packet, err := p.ws.ReadMsg()
if err != nil {
@ -85,14 +90,42 @@ func (p *Peer) handshake() error {
return fmt.Errorf("peer [%x] sent packet %x before status packet", p.ID(), packet.Code)
}
s := rlp.NewStream(packet.Payload, uint64(packet.Size))
peerVersion, err := s.Uint()
_, err = s.List()
if err != nil {
return fmt.Errorf("peer [%x] sent bad status message: %v", p.ID(), err)
}
peerVersion, err := s.Uint()
if err != nil {
return fmt.Errorf("peer [%x] sent bad status message (unable to decode version): %v", p.ID(), err)
}
if peerVersion != ProtocolVersion {
return fmt.Errorf("peer [%x]: protocol version mismatch %d != %d", p.ID(), peerVersion, ProtocolVersion)
}
// Wait until out own status is consumed too
// only version is mandatory, subsequent parameters are optional
powRaw, err := s.Uint()
if err == nil {
pow := math.Float64frombits(powRaw)
if math.IsInf(pow, 0) || math.IsNaN(pow) || pow < 0.0 {
return fmt.Errorf("peer [%x] sent bad status message: invalid pow", p.ID())
}
p.powRequirement = pow
var bloom []byte
err = s.Decode(&bloom)
if err == nil {
sz := len(bloom)
if sz != bloomFilterSize && sz != 0 {
return fmt.Errorf("peer [%x] sent bad status message: wrong bloom filter size %d", p.ID(), sz)
}
if isFullNode(bloom) {
p.bloomFilter = nil
} else {
p.bloomFilter = bloom
}
}
}
if err := <-errc; err != nil {
return fmt.Errorf("peer [%x] failed to send status packet: %v", p.ID(), err)
}
@ -156,7 +189,7 @@ func (p *Peer) broadcast() error {
envelopes := p.host.Envelopes()
bundle := make([]*Envelope, 0, len(envelopes))
for _, envelope := range envelopes {
if !p.marked(envelope) && envelope.PoW() >= p.powRequirement {
if !p.marked(envelope) && envelope.PoW() >= p.powRequirement && p.bloomMatch(envelope) {
bundle = append(bundle, envelope)
}
}
@ -186,3 +219,16 @@ func (p *Peer) notifyAboutPowRequirementChange(pow float64) error {
i := math.Float64bits(pow)
return p2p.Send(p.ws, powRequirementCode, i)
}
func (p *Peer) notifyAboutBloomFilterChange(bloom []byte) error {
return p2p.Send(p.ws, bloomFilterExCode, bloom)
}
func (p *Peer) bloomMatch(env *Envelope) bool {
if p.bloomFilter == nil {
// no filter - full node, accepts all envelops
return true
}
return bloomFilterMatch(p.bloomFilter, env.Bloom())
}

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@ -20,6 +20,7 @@ import (
"bytes"
"crypto/ecdsa"
"fmt"
mrand "math/rand"
"net"
"sync"
"testing"
@ -87,6 +88,9 @@ var nodes [NumNodes]*TestNode
var sharedKey []byte = []byte("some arbitrary data here")
var sharedTopic TopicType = TopicType{0xF, 0x1, 0x2, 0}
var expectedMessage []byte = []byte("per rectum ad astra")
var masterBloomFilter []byte
var masterPow = 0.00000001
var round int = 1
func TestSimulation(t *testing.T) {
// create a chain of whisper nodes,
@ -104,8 +108,13 @@ func TestSimulation(t *testing.T) {
// check if each node have received and decrypted exactly one message
checkPropagation(t, true)
// send protocol-level messages (powRequirementCode) and check the new PoW requirement values
powReqExchange(t)
// check if Status message was correctly decoded
checkBloomFilterExchange(t)
checkPowExchange(t)
// send new pow and bloom exchange messages
resetParams(t)
round++
// node #1 sends one expected (decryptable) message
sendMsg(t, true, 1)
@ -113,18 +122,65 @@ func TestSimulation(t *testing.T) {
// check if each node (except node #0) have received and decrypted exactly one message
checkPropagation(t, false)
for i := 1; i < NumNodes; i++ {
time.Sleep(20 * time.Millisecond)
sendMsg(t, true, i)
}
// check if corresponding protocol-level messages were correctly decoded
checkPowExchangeForNodeZero(t)
checkBloomFilterExchange(t)
stopServers()
}
func resetParams(t *testing.T) {
// change pow only for node zero
masterPow = 7777777.0
nodes[0].shh.SetMinimumPoW(masterPow)
// change bloom for all nodes
masterBloomFilter = TopicToBloom(sharedTopic)
for i := 0; i < NumNodes; i++ {
nodes[i].shh.SetBloomFilter(masterBloomFilter)
}
}
func initBloom(t *testing.T) {
masterBloomFilter = make([]byte, bloomFilterSize)
_, err := mrand.Read(masterBloomFilter)
if err != nil {
t.Fatalf("rand failed: %s.", err)
}
msgBloom := TopicToBloom(sharedTopic)
masterBloomFilter = addBloom(masterBloomFilter, msgBloom)
for i := 0; i < 32; i++ {
masterBloomFilter[i] = 0xFF
}
if !bloomFilterMatch(masterBloomFilter, msgBloom) {
t.Fatalf("bloom mismatch on initBloom.")
}
}
func initialize(t *testing.T) {
initBloom(t)
var err error
ip := net.IPv4(127, 0, 0, 1)
port0 := 30303
for i := 0; i < NumNodes; i++ {
var node TestNode
b := make([]byte, bloomFilterSize)
copy(b, masterBloomFilter)
node.shh = New(&DefaultConfig)
node.shh.SetMinimumPowTest(0.00000001)
node.shh.SetMinimumPoW(masterPow)
node.shh.SetBloomFilter(b)
if !bytes.Equal(node.shh.BloomFilter(), masterBloomFilter) {
t.Fatalf("bloom mismatch on init.")
}
node.shh.Start(nil)
topics := make([]TopicType, 0)
topics = append(topics, sharedTopic)
@ -206,7 +262,7 @@ func checkPropagation(t *testing.T, includingNodeZero bool) {
for i := first; i < NumNodes; i++ {
f := nodes[i].shh.GetFilter(nodes[i].filerId)
if f == nil {
t.Fatalf("failed to get filterId %s from node %d.", nodes[i].filerId, i)
t.Fatalf("failed to get filterId %s from node %d, round %d.", nodes[i].filerId, i, round)
}
mail := f.Retrieve()
@ -332,34 +388,43 @@ func TestPeerBasic(t *testing.T) {
}
}
func powReqExchange(t *testing.T) {
for i, node := range nodes {
for peer := range node.shh.peers {
if peer.powRequirement > 1000.0 {
t.Fatalf("node %d: one of the peers' pow requirement is too big (%f).", i, peer.powRequirement)
}
}
}
const pow float64 = 7777777.0
nodes[0].shh.SetMinimumPoW(pow)
// wait until all the messages are delivered
time.Sleep(64 * time.Millisecond)
func checkPowExchangeForNodeZero(t *testing.T) {
cnt := 0
for i, node := range nodes {
for peer := range node.shh.peers {
if peer.peer.ID() == discover.PubkeyID(&nodes[0].id.PublicKey) {
cnt++
if peer.powRequirement != pow {
if peer.powRequirement != masterPow {
t.Fatalf("node %d: failed to set the new pow requirement.", i)
}
}
}
}
if cnt == 0 {
t.Fatalf("no matching peers found.")
}
}
func checkPowExchange(t *testing.T) {
for i, node := range nodes {
for peer := range node.shh.peers {
if peer.peer.ID() != discover.PubkeyID(&nodes[0].id.PublicKey) {
if peer.powRequirement != masterPow {
t.Fatalf("node %d: failed to exchange pow requirement in round %d; expected %f, got %f",
i, round, masterPow, peer.powRequirement)
}
}
}
}
}
func checkBloomFilterExchange(t *testing.T) {
for i, node := range nodes {
for peer := range node.shh.peers {
if !bytes.Equal(peer.bloomFilter, masterBloomFilter) {
t.Fatalf("node %d: failed to exchange bloom filter requirement in round %d. \n%x expected \n%x got",
i, round, masterBloomFilter, peer.bloomFilter)
}
}
}
}

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@ -48,9 +48,12 @@ type Statistics struct {
}
const (
minPowIdx = iota // Minimal PoW required by the whisper node
maxMsgSizeIdx = iota // Maximal message length allowed by the whisper node
overflowIdx = iota // Indicator of message queue overflow
maxMsgSizeIdx = iota // Maximal message length allowed by the whisper node
overflowIdx // Indicator of message queue overflow
minPowIdx // Minimal PoW required by the whisper node
minPowToleranceIdx // Minimal PoW tolerated by the whisper node for a limited time
bloomFilterIdx // Bloom filter for topics of interest for this node
bloomFilterToleranceIdx // Bloom filter tolerated by the whisper node for a limited time
)
// Whisper represents a dark communication interface through the Ethereum
@ -76,7 +79,7 @@ type Whisper struct {
settings syncmap.Map // holds configuration settings that can be dynamically changed
reactionAllowance int // maximum time in seconds allowed to process the whisper-related messages
syncAllowance int // maximum time in seconds allowed to process the whisper-related messages
statsMu sync.Mutex // guard stats
stats Statistics // Statistics of whisper node
@ -91,15 +94,15 @@ func New(cfg *Config) *Whisper {
}
whisper := &Whisper{
privateKeys: make(map[string]*ecdsa.PrivateKey),
symKeys: make(map[string][]byte),
envelopes: make(map[common.Hash]*Envelope),
expirations: make(map[uint32]*set.SetNonTS),
peers: make(map[*Peer]struct{}),
messageQueue: make(chan *Envelope, messageQueueLimit),
p2pMsgQueue: make(chan *Envelope, messageQueueLimit),
quit: make(chan struct{}),
reactionAllowance: SynchAllowance,
privateKeys: make(map[string]*ecdsa.PrivateKey),
symKeys: make(map[string][]byte),
envelopes: make(map[common.Hash]*Envelope),
expirations: make(map[uint32]*set.SetNonTS),
peers: make(map[*Peer]struct{}),
messageQueue: make(chan *Envelope, messageQueueLimit),
p2pMsgQueue: make(chan *Envelope, messageQueueLimit),
quit: make(chan struct{}),
syncAllowance: DefaultSyncAllowance,
}
whisper.filters = NewFilters(whisper)
@ -126,11 +129,55 @@ func New(cfg *Config) *Whisper {
return whisper
}
// MinPow returns the PoW value required by this node.
func (w *Whisper) MinPow() float64 {
val, _ := w.settings.Load(minPowIdx)
val, exist := w.settings.Load(minPowIdx)
if !exist || val == nil {
return DefaultMinimumPoW
}
v, ok := val.(float64)
if !ok {
log.Error("Error loading minPowIdx, using default")
return DefaultMinimumPoW
}
return v
}
// MinPowTolerance returns the value of minimum PoW which is tolerated for a limited
// time after PoW was changed. If sufficient time have elapsed or no change of PoW
// have ever occurred, the return value will be the same as return value of MinPow().
func (w *Whisper) MinPowTolerance() float64 {
val, exist := w.settings.Load(minPowToleranceIdx)
if !exist || val == nil {
return DefaultMinimumPoW
}
return val.(float64)
}
// BloomFilter returns the aggregated bloom filter for all the topics of interest.
// The nodes are required to send only messages that match the advertised bloom filter.
// If a message does not match the bloom, it will tantamount to spam, and the peer will
// be disconnected.
func (w *Whisper) BloomFilter() []byte {
val, exist := w.settings.Load(bloomFilterIdx)
if !exist || val == nil {
return nil
}
return val.([]byte)
}
// BloomFilterTolerance returns the bloom filter which is tolerated for a limited
// time after new bloom was advertised to the peers. If sufficient time have elapsed
// or no change of bloom filter have ever occurred, the return value will be the same
// as return value of BloomFilter().
func (w *Whisper) BloomFilterTolerance() []byte {
val, exist := w.settings.Load(bloomFilterToleranceIdx)
if !exist || val == nil {
return nil
}
return val.([]byte)
}
// MaxMessageSize returns the maximum accepted message size.
func (w *Whisper) MaxMessageSize() uint32 {
val, _ := w.settings.Load(maxMsgSizeIdx)
@ -180,18 +227,40 @@ func (w *Whisper) SetMaxMessageSize(size uint32) error {
return nil
}
// SetBloomFilter sets the new bloom filter
func (w *Whisper) SetBloomFilter(bloom []byte) error {
if len(bloom) != bloomFilterSize {
return fmt.Errorf("invalid bloom filter size: %d", len(bloom))
}
b := make([]byte, bloomFilterSize)
copy(b, bloom)
w.settings.Store(bloomFilterIdx, b)
w.notifyPeersAboutBloomFilterChange(b)
go func() {
// allow some time before all the peers have processed the notification
time.Sleep(time.Duration(w.syncAllowance) * time.Second)
w.settings.Store(bloomFilterToleranceIdx, b)
}()
return nil
}
// SetMinimumPoW sets the minimal PoW required by this node
func (w *Whisper) SetMinimumPoW(val float64) error {
if val < 0.0 {
return fmt.Errorf("invalid PoW: %f", val)
}
w.settings.Store(minPowIdx, val)
w.notifyPeersAboutPowRequirementChange(val)
go func() {
// allow some time before all the peers have processed the notification
time.Sleep(time.Duration(w.reactionAllowance) * time.Second)
w.settings.Store(minPowIdx, val)
time.Sleep(time.Duration(w.syncAllowance) * time.Second)
w.settings.Store(minPowToleranceIdx, val)
}()
return nil
@ -199,21 +268,13 @@ func (w *Whisper) SetMinimumPoW(val float64) error {
// SetMinimumPoW sets the minimal PoW in test environment
func (w *Whisper) SetMinimumPowTest(val float64) {
w.notifyPeersAboutPowRequirementChange(val)
w.settings.Store(minPowIdx, val)
w.notifyPeersAboutPowRequirementChange(val)
w.settings.Store(minPowToleranceIdx, val)
}
func (w *Whisper) notifyPeersAboutPowRequirementChange(pow float64) {
arr := make([]*Peer, len(w.peers))
i := 0
w.peerMu.Lock()
for p := range w.peers {
arr[i] = p
i++
}
w.peerMu.Unlock()
arr := w.getPeers()
for _, p := range arr {
err := p.notifyAboutPowRequirementChange(pow)
if err != nil {
@ -221,11 +282,37 @@ func (w *Whisper) notifyPeersAboutPowRequirementChange(pow float64) {
err = p.notifyAboutPowRequirementChange(pow)
}
if err != nil {
log.Warn("oversized message received", "peer", p.ID(), "error", err)
log.Warn("failed to notify peer about new pow requirement", "peer", p.ID(), "error", err)
}
}
}
func (w *Whisper) notifyPeersAboutBloomFilterChange(bloom []byte) {
arr := w.getPeers()
for _, p := range arr {
err := p.notifyAboutBloomFilterChange(bloom)
if err != nil {
// allow one retry
err = p.notifyAboutBloomFilterChange(bloom)
}
if err != nil {
log.Warn("failed to notify peer about new bloom filter", "peer", p.ID(), "error", err)
}
}
}
func (w *Whisper) getPeers() []*Peer {
arr := make([]*Peer, len(w.peers))
i := 0
w.peerMu.Lock()
for p := range w.peers {
arr[i] = p
i++
}
w.peerMu.Unlock()
return arr
}
// getPeer retrieves peer by ID
func (w *Whisper) getPeer(peerID []byte) (*Peer, error) {
w.peerMu.Lock()
@ -459,7 +546,28 @@ func (w *Whisper) GetSymKey(id string) ([]byte, error) {
// Subscribe installs a new message handler used for filtering, decrypting
// and subsequent storing of incoming messages.
func (w *Whisper) Subscribe(f *Filter) (string, error) {
return w.filters.Install(f)
s, err := w.filters.Install(f)
if err == nil {
w.updateBloomFilter(f)
}
return s, err
}
// updateBloomFilter recalculates the new value of bloom filter,
// and informs the peers if necessary.
func (w *Whisper) updateBloomFilter(f *Filter) {
aggregate := make([]byte, bloomFilterSize)
for _, t := range f.Topics {
top := BytesToTopic(t)
b := TopicToBloom(top)
aggregate = addBloom(aggregate, b)
}
if !bloomFilterMatch(w.BloomFilter(), aggregate) {
// existing bloom filter must be updated
aggregate = addBloom(w.BloomFilter(), aggregate)
w.SetBloomFilter(aggregate)
}
}
// GetFilter returns the filter by id.
@ -592,7 +700,21 @@ func (wh *Whisper) runMessageLoop(p *Peer, rw p2p.MsgReadWriter) error {
}
p.powRequirement = f
case bloomFilterExCode:
// to be implemented
var bloom []byte
err := packet.Decode(&bloom)
if err == nil && len(bloom) != bloomFilterSize {
err = fmt.Errorf("wrong bloom filter size %d", len(bloom))
}
if err != nil {
log.Warn("failed to decode bloom filter exchange message, peer will be disconnected", "peer", p.peer.ID(), "err", err)
return errors.New("invalid bloom filter exchange message")
}
if isFullNode(bloom) {
p.bloomFilter = nil
} else {
p.bloomFilter = bloom
}
case p2pMessageCode:
// peer-to-peer message, sent directly to peer bypassing PoW checks, etc.
// this message is not supposed to be forwarded to other peers, and
@ -633,7 +755,7 @@ func (wh *Whisper) add(envelope *Envelope) (bool, error) {
sent := envelope.Expiry - envelope.TTL
if sent > now {
if sent-SynchAllowance > now {
if sent-DefaultSyncAllowance > now {
return false, fmt.Errorf("envelope created in the future [%x]", envelope.Hash())
} else {
// recalculate PoW, adjusted for the time difference, plus one second for latency
@ -642,7 +764,7 @@ func (wh *Whisper) add(envelope *Envelope) (bool, error) {
}
if envelope.Expiry < now {
if envelope.Expiry+SynchAllowance*2 < now {
if envelope.Expiry+DefaultSyncAllowance*2 < now {
return false, fmt.Errorf("very old message")
} else {
log.Debug("expired envelope dropped", "hash", envelope.Hash().Hex())
@ -655,11 +777,22 @@ func (wh *Whisper) add(envelope *Envelope) (bool, error) {
}
if envelope.PoW() < wh.MinPow() {
log.Debug("envelope with low PoW dropped", "PoW", envelope.PoW(), "hash", envelope.Hash().Hex())
return false, nil // drop envelope without error for now
// maybe the value was recently changed, and the peers did not adjust yet.
// in this case the previous value is retrieved by MinPowTolerance()
// for a short period of peer synchronization.
if envelope.PoW() < wh.MinPowTolerance() {
return false, fmt.Errorf("envelope with low PoW received: PoW=%f, hash=[%v]", envelope.PoW(), envelope.Hash().Hex())
}
}
// once the status message includes the PoW requirement, an error should be returned here:
//return false, fmt.Errorf("envelope with low PoW dropped: PoW=%f, hash=[%v]", envelope.PoW(), envelope.Hash().Hex())
if !bloomFilterMatch(wh.BloomFilter(), envelope.Bloom()) {
// maybe the value was recently changed, and the peers did not adjust yet.
// in this case the previous value is retrieved by BloomFilterTolerance()
// for a short period of peer synchronization.
if !bloomFilterMatch(wh.BloomFilterTolerance(), envelope.Bloom()) {
return false, fmt.Errorf("envelope does not match bloom filter, hash=[%v], bloom: \n%x \n%x \n%x",
envelope.Hash().Hex(), wh.BloomFilter(), envelope.Bloom(), envelope.Topic)
}
}
hash := envelope.Hash()
@ -897,3 +1030,40 @@ func GenerateRandomID() (id string, err error) {
id = common.Bytes2Hex(buf)
return id, err
}
func isFullNode(bloom []byte) bool {
if bloom == nil {
return true
}
for _, b := range bloom {
if b != 255 {
return false
}
}
return true
}
func bloomFilterMatch(filter, sample []byte) bool {
if filter == nil {
// full node, accepts all messages
return true
}
for i := 0; i < bloomFilterSize; i++ {
f := filter[i]
s := sample[i]
if (f | s) != f {
return false
}
}
return true
}
func addBloom(a, b []byte) []byte {
c := make([]byte, bloomFilterSize)
for i := 0; i < bloomFilterSize; i++ {
c[i] = a[i] | b[i]
}
return c
}

View File

@ -843,3 +843,64 @@ func TestSymmetricSendKeyMismatch(t *testing.T) {
t.Fatalf("received a message when keys weren't matching")
}
}
func TestBloom(t *testing.T) {
topic := TopicType{0, 0, 255, 6}
b := TopicToBloom(topic)
x := make([]byte, bloomFilterSize)
x[0] = byte(1)
x[32] = byte(1)
x[bloomFilterSize-1] = byte(128)
if !bloomFilterMatch(x, b) || !bloomFilterMatch(b, x) {
t.Fatalf("bloom filter does not match the mask")
}
_, err := mrand.Read(b)
if err != nil {
t.Fatalf("math rand error")
}
_, err = mrand.Read(x)
if err != nil {
t.Fatalf("math rand error")
}
if !bloomFilterMatch(b, b) {
t.Fatalf("bloom filter does not match self")
}
x = addBloom(x, b)
if !bloomFilterMatch(x, b) {
t.Fatalf("bloom filter does not match combined bloom")
}
if !isFullNode(nil) {
t.Fatalf("isFullNode did not recognize nil as full node")
}
x[17] = 254
if isFullNode(x) {
t.Fatalf("isFullNode false positive")
}
for i := 0; i < bloomFilterSize; i++ {
b[i] = byte(255)
}
if !isFullNode(b) {
t.Fatalf("isFullNode false negative")
}
if bloomFilterMatch(x, b) {
t.Fatalf("bloomFilterMatch false positive")
}
if !bloomFilterMatch(b, x) {
t.Fatalf("bloomFilterMatch false negative")
}
w := New(&DefaultConfig)
f := w.BloomFilter()
if f != nil {
t.Fatalf("wrong bloom on creation")
}
err = w.SetBloomFilter(x)
if err != nil {
t.Fatalf("failed to set bloom filter: %s", err)
}
f = w.BloomFilter()
if !bloomFilterMatch(f, x) || !bloomFilterMatch(x, f) {
t.Fatalf("retireved wrong bloom filter")
}
}