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transport.go
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transport.go
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package transport
import (
"bytes"
"context"
"crypto/ecdsa"
"database/sql"
"encoding/hex"
"fmt"
"sync"
"time"
"github.com/google/uuid"
"github.com/libp2p/go-libp2p/core/peer"
"github.com/pkg/errors"
"go.uber.org/zap"
"github.com/ethereum/go-ethereum/common"
"github.com/status-im/status-go/connection"
"github.com/status-im/status-go/eth-node/crypto"
"github.com/status-im/status-go/eth-node/types"
)
var (
// ErrNoMailservers returned if there is no configured mailservers that can be used.
ErrNoMailservers = errors.New("no configured mailservers")
)
type transportKeysManager struct {
waku types.Waku
// Identity of the current user.
privateKey *ecdsa.PrivateKey
passToSymKeyMutex sync.RWMutex
passToSymKeyCache map[string]string
}
func (m *transportKeysManager) AddOrGetKeyPair(priv *ecdsa.PrivateKey) (string, error) {
// caching is handled in waku
return m.waku.AddKeyPair(priv)
}
func (m *transportKeysManager) AddOrGetSymKeyFromPassword(password string) (string, error) {
m.passToSymKeyMutex.Lock()
defer m.passToSymKeyMutex.Unlock()
if val, ok := m.passToSymKeyCache[password]; ok {
return val, nil
}
id, err := m.waku.AddSymKeyFromPassword(password)
if err != nil {
return id, err
}
m.passToSymKeyCache[password] = id
return id, nil
}
func (m *transportKeysManager) RawSymKey(id string) ([]byte, error) {
return m.waku.GetSymKey(id)
}
type Option func(*Transport) error
// Transport is a transport based on Whisper service.
type Transport struct {
waku types.Waku
api types.PublicWakuAPI // only PublicWakuAPI implements logic to send messages
keysManager *transportKeysManager
filters *FiltersManager
logger *zap.Logger
cache *ProcessedMessageIDsCache
mailservers []string
envelopesMonitor *EnvelopesMonitor
quit chan struct{}
}
// NewTransport returns a new Transport.
// TODO: leaving a chat should verify that for a given public key
//
// there are no other chats. It may happen that we leave a private chat
// but still have a public chat for a given public key.
func NewTransport(
waku types.Waku,
privateKey *ecdsa.PrivateKey,
db *sql.DB,
sqlitePersistenceTableName string,
mailservers []string,
envelopesMonitorConfig *EnvelopesMonitorConfig,
logger *zap.Logger,
opts ...Option,
) (*Transport, error) {
filtersManager, err := NewFiltersManager(newSQLitePersistence(db, sqlitePersistenceTableName), waku, privateKey, logger)
if err != nil {
return nil, err
}
var envelopesMonitor *EnvelopesMonitor
if envelopesMonitorConfig != nil {
envelopesMonitor = NewEnvelopesMonitor(waku, *envelopesMonitorConfig)
envelopesMonitor.Start()
}
var api types.PublicWhisperAPI
if waku != nil {
api = waku.PublicWakuAPI()
}
t := &Transport{
waku: waku,
api: api,
cache: NewProcessedMessageIDsCache(db),
envelopesMonitor: envelopesMonitor,
quit: make(chan struct{}),
keysManager: &transportKeysManager{
waku: waku,
privateKey: privateKey,
passToSymKeyCache: make(map[string]string),
},
filters: filtersManager,
mailservers: mailservers,
logger: logger.With(zap.Namespace("Transport")),
}
for _, opt := range opts {
if err := opt(t); err != nil {
return nil, err
}
}
t.cleanFiltersLoop()
return t, nil
}
func (t *Transport) InitFilters(chatIDs []FiltersToInitialize, publicKeys []*ecdsa.PublicKey) ([]*Filter, error) {
return t.filters.Init(chatIDs, publicKeys)
}
func (t *Transport) InitPublicFilters(filtersToInit []FiltersToInitialize) ([]*Filter, error) {
return t.filters.InitPublicFilters(filtersToInit)
}
func (t *Transport) Filters() []*Filter {
return t.filters.Filters()
}
func (t *Transport) FilterByChatID(chatID string) *Filter {
return t.filters.FilterByChatID(chatID)
}
func (t *Transport) FilterByTopic(topic []byte) *Filter {
return t.filters.FilterByTopic(topic)
}
func (t *Transport) FiltersByIdentities(identities []string) []*Filter {
return t.filters.FiltersByIdentities(identities)
}
func (t *Transport) LoadFilters(filters []*Filter) ([]*Filter, error) {
return t.filters.InitWithFilters(filters)
}
func (t *Transport) InitCommunityFilters(communityFiltersToInitialize []CommunityFilterToInitialize, useShards bool) ([]*Filter, error) {
return t.filters.InitCommunityFilters(communityFiltersToInitialize, useShards)
}
func (t *Transport) RemoveFilters(filters []*Filter) error {
return t.filters.Remove(context.Background(), filters...)
}
func (t *Transport) RemoveFilterByChatID(chatID string) (*Filter, error) {
return t.filters.RemoveFilterByChatID(chatID)
}
func (t *Transport) ResetFilters(ctx context.Context) error {
return t.filters.Reset(ctx)
}
func (t *Transport) ProcessNegotiatedSecret(secret types.NegotiatedSecret) (*Filter, error) {
filter, err := t.filters.LoadNegotiated(secret)
if err != nil {
return nil, err
}
return filter, nil
}
func (t *Transport) JoinPublic(chatID string) (*Filter, error) {
return t.filters.LoadPublic(chatID, "")
}
func (t *Transport) LeavePublic(chatID string) error {
chat := t.filters.Filter(chatID)
if chat != nil {
return nil
}
return t.filters.Remove(context.Background(), chat)
}
func (t *Transport) JoinPrivate(publicKey *ecdsa.PublicKey) (*Filter, error) {
return t.filters.LoadContactCode(publicKey)
}
func (t *Transport) JoinGroup(publicKeys []*ecdsa.PublicKey) ([]*Filter, error) {
var filters []*Filter
for _, pk := range publicKeys {
f, err := t.filters.LoadContactCode(pk)
if err != nil {
return nil, err
}
filters = append(filters, f)
}
return filters, nil
}
func (t *Transport) GetStats() types.StatsSummary {
return t.waku.GetStats()
}
func (t *Transport) RetrieveRawAll() (map[Filter][]*types.Message, error) {
result := make(map[Filter][]*types.Message)
logger := t.logger.With(zap.String("site", "retrieveRawAll"))
for _, filter := range t.filters.Filters() {
msgs, err := t.api.GetFilterMessages(filter.FilterID)
if err != nil {
logger.Warn("failed to fetch messages", zap.Error(err))
continue
}
// Don't pull from filters we don't listen to
if !filter.Listen {
for _, msg := range msgs {
t.waku.MarkP2PMessageAsProcessed(common.BytesToHash(msg.Hash))
}
continue
}
if len(msgs) == 0 {
continue
}
ids := make([]string, len(msgs))
for i := range msgs {
id := types.EncodeHex(msgs[i].Hash)
ids[i] = id
}
hits, err := t.cache.Hits(ids)
if err != nil {
logger.Error("failed to check messages exists", zap.Error(err))
return nil, err
}
for i := range msgs {
// Exclude anything that is a cache hit
if !hits[types.EncodeHex(msgs[i].Hash)] {
result[*filter] = append(result[*filter], msgs[i])
logger.Debug("message not cached", zap.String("hash", types.EncodeHex(msgs[i].Hash)))
} else {
logger.Debug("message cached", zap.String("hash", types.EncodeHex(msgs[i].Hash)))
t.waku.MarkP2PMessageAsProcessed(common.BytesToHash(msgs[i].Hash))
}
}
}
return result, nil
}
// SendPublic sends a new message using the Whisper service.
// For public filters, chat name is used as an ID as well as
// a topic.
func (t *Transport) SendPublic(ctx context.Context, newMessage *types.NewMessage, chatName string) ([]byte, error) {
if err := t.addSig(newMessage); err != nil {
return nil, err
}
filter, err := t.filters.LoadPublic(chatName, newMessage.PubsubTopic)
if err != nil {
return nil, err
}
newMessage.SymKeyID = filter.SymKeyID
newMessage.Topic = filter.ContentTopic
newMessage.PubsubTopic = filter.PubsubTopic
return t.api.Post(ctx, *newMessage)
}
func (t *Transport) SendPrivateWithSharedSecret(ctx context.Context, newMessage *types.NewMessage, publicKey *ecdsa.PublicKey, secret []byte) ([]byte, error) {
if err := t.addSig(newMessage); err != nil {
return nil, err
}
filter, err := t.filters.LoadNegotiated(types.NegotiatedSecret{
PublicKey: publicKey,
Key: secret,
})
if err != nil {
return nil, err
}
newMessage.SymKeyID = filter.SymKeyID
newMessage.Topic = filter.ContentTopic
newMessage.PubsubTopic = filter.PubsubTopic
newMessage.PublicKey = nil
return t.api.Post(ctx, *newMessage)
}
func (t *Transport) SendPrivateWithPartitioned(ctx context.Context, newMessage *types.NewMessage, publicKey *ecdsa.PublicKey) ([]byte, error) {
if err := t.addSig(newMessage); err != nil {
return nil, err
}
filter, err := t.filters.LoadPartitioned(publicKey, t.keysManager.privateKey, false)
if err != nil {
return nil, err
}
newMessage.PubsubTopic = filter.PubsubTopic
newMessage.Topic = filter.ContentTopic
newMessage.PublicKey = crypto.FromECDSAPub(publicKey)
return t.api.Post(ctx, *newMessage)
}
func (t *Transport) SendPrivateOnPersonalTopic(ctx context.Context, newMessage *types.NewMessage, publicKey *ecdsa.PublicKey) ([]byte, error) {
if err := t.addSig(newMessage); err != nil {
return nil, err
}
filter, err := t.filters.LoadPersonal(publicKey, t.keysManager.privateKey, false)
if err != nil {
return nil, err
}
newMessage.PubsubTopic = filter.PubsubTopic
newMessage.Topic = filter.ContentTopic
newMessage.PublicKey = crypto.FromECDSAPub(publicKey)
return t.api.Post(ctx, *newMessage)
}
func (t *Transport) PersonalTopicFilter() *Filter {
return t.filters.PersonalTopicFilter()
}
func (t *Transport) LoadKeyFilters(key *ecdsa.PrivateKey) (*Filter, error) {
return t.filters.LoadEphemeral(&key.PublicKey, key, true)
}
func (t *Transport) SendCommunityMessage(ctx context.Context, newMessage *types.NewMessage, publicKey *ecdsa.PublicKey) ([]byte, error) {
if err := t.addSig(newMessage); err != nil {
return nil, err
}
// We load the filter to make sure we can post on it
filter, err := t.filters.LoadPublic(PubkeyToHex(publicKey)[2:], newMessage.PubsubTopic)
if err != nil {
return nil, err
}
newMessage.PubsubTopic = filter.PubsubTopic
newMessage.Topic = filter.ContentTopic
newMessage.PublicKey = crypto.FromECDSAPub(publicKey)
t.logger.Debug("SENDING message", zap.Binary("topic", filter.ContentTopic[:]))
return t.api.Post(ctx, *newMessage)
}
func (t *Transport) cleanFilters() error {
return t.filters.RemoveNoListenFilters()
}
func (t *Transport) addSig(newMessage *types.NewMessage) error {
sigID, err := t.keysManager.AddOrGetKeyPair(t.keysManager.privateKey)
if err != nil {
return err
}
newMessage.SigID = sigID
return nil
}
func (t *Transport) Track(identifier []byte, hashes [][]byte, newMessages []*types.NewMessage) {
t.TrackMany([][]byte{identifier}, hashes, newMessages)
}
func (t *Transport) TrackMany(identifiers [][]byte, hashes [][]byte, newMessages []*types.NewMessage) {
if t.envelopesMonitor == nil {
return
}
envelopeHashes := make([]types.Hash, len(hashes))
for i, hash := range hashes {
envelopeHashes[i] = types.BytesToHash(hash)
}
err := t.envelopesMonitor.Add(identifiers, envelopeHashes, newMessages)
if err != nil {
t.logger.Error("failed to track messages", zap.Error(err))
}
}
// GetCurrentTime returns the current unix timestamp in milliseconds
func (t *Transport) GetCurrentTime() uint64 {
return uint64(t.waku.GetCurrentTime().UnixNano() / int64(time.Millisecond))
}
func (t *Transport) MaxMessageSize() uint32 {
return t.waku.MaxMessageSize()
}
func (t *Transport) Stop() error {
close(t.quit)
if t.envelopesMonitor != nil {
t.envelopesMonitor.Stop()
}
return nil
}
// cleanFiltersLoop cleans up the topic we create for the only purpose
// of sending messages.
// Whenever we send a message we also need to listen to that particular topic
// but in case of asymettric topics, we are not interested in listening to them.
// We therefore periodically clean them up so we don't receive unnecessary data.
func (t *Transport) cleanFiltersLoop() {
ticker := time.NewTicker(5 * time.Minute)
go func() {
for {
select {
case <-t.quit:
ticker.Stop()
return
case <-ticker.C:
err := t.cleanFilters()
if err != nil {
t.logger.Error("failed to clean up topics", zap.Error(err))
}
}
}
}()
}
func (t *Transport) WakuVersion() uint {
return t.waku.Version()
}
func (t *Transport) PeerCount() int {
return t.waku.PeerCount()
}
func (t *Transport) Peers() map[string]types.WakuV2Peer {
return t.waku.Peers()
}
func (t *Transport) createMessagesRequestV1(
ctx context.Context,
peerID []byte,
from, to uint32,
previousCursor []byte,
topics []types.TopicType,
waitForResponse bool,
) (cursor []byte, err error) {
r := createMessagesRequest(from, to, previousCursor, nil, "", topics, 1000)
events := make(chan types.EnvelopeEvent, 10)
sub := t.waku.SubscribeEnvelopeEvents(events)
defer sub.Unsubscribe()
err = t.waku.SendMessagesRequest(peerID, r)
if err != nil {
return
}
if !waitForResponse {
return
}
var resp *types.MailServerResponse
resp, err = t.waitForRequestCompleted(ctx, r.ID, events)
if err == nil && resp != nil && resp.Error != nil {
err = resp.Error
} else if err == nil && resp != nil {
cursor = resp.Cursor
}
return
}
func (t *Transport) createMessagesRequestV2(
ctx context.Context,
peerID []byte,
from, to uint32,
previousStoreCursor *types.StoreRequestCursor,
pubsubTopic string,
contentTopics []types.TopicType,
limit uint32,
waitForResponse bool,
processEnvelopes bool,
) (storeCursor *types.StoreRequestCursor, envelopesCount int, err error) {
r := createMessagesRequest(from, to, nil, previousStoreCursor, pubsubTopic, contentTopics, limit)
if waitForResponse {
resultCh := make(chan struct {
storeCursor *types.StoreRequestCursor
envelopesCount int
err error
})
go func() {
storeCursor, envelopesCount, err = t.waku.RequestStoreMessages(ctx, peerID, r, processEnvelopes)
resultCh <- struct {
storeCursor *types.StoreRequestCursor
envelopesCount int
err error
}{storeCursor, envelopesCount, err}
}()
select {
case result := <-resultCh:
return result.storeCursor, result.envelopesCount, result.err
case <-ctx.Done():
return nil, 0, ctx.Err()
}
} else {
go func() {
_, _, err = t.waku.RequestStoreMessages(ctx, peerID, r, false)
if err != nil {
t.logger.Error("failed to request store messages", zap.Error(err))
}
}()
}
return
}
func (t *Transport) SendMessagesRequestForTopics(
ctx context.Context,
peerID []byte,
from, to uint32,
previousCursor []byte,
previousStoreCursor *types.StoreRequestCursor,
pubsubTopic string,
contentTopics []types.TopicType,
limit uint32,
waitForResponse bool,
processEnvelopes bool,
) (cursor []byte, storeCursor *types.StoreRequestCursor, envelopesCount int, err error) {
switch t.waku.Version() {
case 2:
storeCursor, envelopesCount, err = t.createMessagesRequestV2(ctx, peerID, from, to, previousStoreCursor, pubsubTopic, contentTopics, limit, waitForResponse, processEnvelopes)
case 1:
cursor, err = t.createMessagesRequestV1(ctx, peerID, from, to, previousCursor, contentTopics, waitForResponse)
default:
err = fmt.Errorf("unsupported version %d", t.waku.Version())
}
return
}
func createMessagesRequest(from, to uint32, cursor []byte, storeCursor *types.StoreRequestCursor, pubsubTopic string, topics []types.TopicType, limit uint32) types.MessagesRequest {
aUUID := uuid.New()
// uuid is 16 bytes, converted to hex it's 32 bytes as expected by types.MessagesRequest
id := []byte(hex.EncodeToString(aUUID[:]))
var topicBytes [][]byte
for idx := range topics {
topicBytes = append(topicBytes, topics[idx][:])
}
return types.MessagesRequest{
ID: id,
From: from,
To: to,
Limit: limit,
Cursor: cursor,
PubsubTopic: pubsubTopic,
ContentTopics: topicBytes,
StoreCursor: storeCursor,
}
}
func (t *Transport) waitForRequestCompleted(ctx context.Context, requestID []byte, events chan types.EnvelopeEvent) (*types.MailServerResponse, error) {
for {
select {
case ev := <-events:
if !bytes.Equal(ev.Hash.Bytes(), requestID) {
continue
}
if ev.Event != types.EventMailServerRequestCompleted {
continue
}
data, ok := ev.Data.(*types.MailServerResponse)
if ok {
return data, nil
}
case <-ctx.Done():
return nil, ctx.Err()
}
}
}
// ConfirmMessagesProcessed marks the messages as processed in the cache so
// they won't be passed to the next layer anymore
func (t *Transport) ConfirmMessagesProcessed(ids []string, timestamp uint64) error {
t.logger.Debug("confirming message processed", zap.Any("ids", ids), zap.Any("timestamp", timestamp))
return t.cache.Add(ids, timestamp)
}
// CleanMessagesProcessed clears the messages that are older than timestamp
func (t *Transport) CleanMessagesProcessed(timestamp uint64) error {
return t.cache.Clean(timestamp)
}
func (t *Transport) SetEnvelopeEventsHandler(handler EnvelopeEventsHandler) error {
if t.envelopesMonitor == nil {
return errors.New("Current transport has no envelopes monitor")
}
t.envelopesMonitor.handler = handler
return nil
}
func (t *Transport) ClearProcessedMessageIDsCache() error {
t.logger.Debug("clearing processed messages cache")
t.waku.ClearEnvelopesCache()
return t.cache.Clear()
}
func (t *Transport) BloomFilter() []byte {
return t.api.BloomFilter()
}
func PubkeyToHex(key *ecdsa.PublicKey) string {
return types.EncodeHex(crypto.FromECDSAPub(key))
}
func (t *Transport) StartDiscV5() error {
return t.waku.StartDiscV5()
}
func (t *Transport) StopDiscV5() error {
return t.waku.StopDiscV5()
}
func (t *Transport) ListenAddresses() ([]string, error) {
return t.waku.ListenAddresses()
}
func (t *Transport) AddStorePeer(address string) (peer.ID, error) {
return t.waku.AddStorePeer(address)
}
func (t *Transport) AddRelayPeer(address string) (peer.ID, error) {
return t.waku.AddRelayPeer(address)
}
func (t *Transport) DialPeer(address string) error {
return t.waku.DialPeer(address)
}
func (t *Transport) DialPeerByID(peerID string) error {
return t.waku.DialPeerByID(peerID)
}
func (t *Transport) DropPeer(peerID string) error {
return t.waku.DropPeer(peerID)
}
func (t *Transport) ProcessingP2PMessages() bool {
return t.waku.ProcessingP2PMessages()
}
func (t *Transport) MarkP2PMessageAsProcessed(hash common.Hash) {
t.waku.MarkP2PMessageAsProcessed(hash)
}
func (t *Transport) SubscribeToConnStatusChanges() (*types.ConnStatusSubscription, error) {
return t.waku.SubscribeToConnStatusChanges()
}
func (t *Transport) ConnectionChanged(state connection.State) {
t.waku.ConnectionChanged(state)
}
// Subscribe to a pubsub topic, passing an optional public key if the pubsub topic is protected
func (t *Transport) SubscribeToPubsubTopic(topic string, optPublicKey *ecdsa.PublicKey) error {
if t.waku.Version() == 2 {
return t.waku.SubscribeToPubsubTopic(topic, optPublicKey)
}
return nil
}
// Unsubscribe from a pubsub topic
func (t *Transport) UnsubscribeFromPubsubTopic(topic string) error {
if t.waku.Version() == 2 {
return t.waku.UnsubscribeFromPubsubTopic(topic)
}
return nil
}
func (t *Transport) StorePubsubTopicKey(topic string, privKey *ecdsa.PrivateKey) error {
return t.waku.StorePubsubTopicKey(topic, privKey)
}
func (t *Transport) RetrievePubsubTopicKey(topic string) (*ecdsa.PrivateKey, error) {
return t.waku.RetrievePubsubTopicKey(topic)
}
func (t *Transport) RemovePubsubTopicKey(topic string) error {
if t.waku.Version() == 2 {
return t.waku.RemovePubsubTopicKey(topic)
}
return nil
}