// getValueOrPeers queries a particular peer p for the value for
// key. It returns either the value or a list of closer peers.
// NOTE: it will update the dht's peerstore with any new addresses
// it finds for the given peer.
func (dht *IpfsDHT) getValueOrPeers(ctx context.Context, p peer.ID,
key key.Key) ([]byte, []peer.PeerInfo, error) {
pmes, err := dht.getValueSingle(ctx, p, key)
if err != nil {
return nil, nil, err
}
if record := pmes.GetRecord(); record != nil {
// Success! We were given the value
log.Debug("getValueOrPeers: got value")
// make sure record is valid.
err = dht.verifyRecordOnline(ctx, record)
if err != nil {
log.Info("Received invalid record! (discarded)")
return nil, nil, err
}
return record.GetValue(), nil, nil
}
// Perhaps we were given closer peers
peers := pb.PBPeersToPeerInfos(pmes.GetCloserPeers())
if len(peers) > 0 {
log.Debug("getValueOrPeers: peers")
return nil, peers, nil
}
log.Warning("getValueOrPeers: routing.ErrNotFound")
return nil, nil, routing.ErrNotFound
}
func (dht *IpfsDHT) getPublicKeyFromNode(ctx context.Context, p peer.ID) (ci.PubKey, error) {
// check locally, just in case...
pk := dht.peerstore.PubKey(p)
if pk != nil {
return pk, nil
}
pkkey := routing.KeyForPublicKey(p)
pmes, err := dht.getValueSingle(ctx, p, pkkey)
if err != nil {
return nil, err
}
// node doesn't have key :(
record := pmes.GetRecord()
if record == nil {
return nil, fmt.Errorf("Node not responding with its public key: %s", p)
}
// Success! We were given the value. we don't need to check
// validity because a) we can't. b) we know the hash of the
// key we're looking for.
val := record.GetValue()
log.Debug("DHT got a value from other peer")
pk, err = ci.UnmarshalPublicKey(val)
if err != nil {
return nil, err
}
id, err := peer.IDFromPublicKey(pk)
if err != nil {
return nil, err
}
if id != p {
return nil, fmt.Errorf("public key does not match id: %s", p)
}
// ok! it's valid. we got it!
log.Debugf("DHT got public key from node itself.")
return pk, nil
}