Пример #1
0
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
}
Пример #2
0
func (dht *IpfsDHT) GetPublicKey(ctx context.Context, p peer.ID) (ci.PubKey, error) {
	log.Debugf("getPublicKey for: %s", p)

	// check locally.
	pk := dht.peerstore.PubKey(p)
	if pk != nil {
		return pk, nil
	}

	// ok, try the node itself. if they're overwhelmed or slow we can move on.
	ctxT, cancelFunc := ctxfrac.WithDeadlineFraction(ctx, 0.3)
	defer cancelFunc()
	if pk, err := dht.getPublicKeyFromNode(ctx, p); err == nil {
		err := dht.peerstore.AddPubKey(p, pk)
		if err != nil {
			return pk, err
		}
		return pk, nil
	}

	// last ditch effort: let's try the dht.
	log.Debugf("pk for %s not in peerstore, and peer failed. Trying DHT.", p)
	pkkey := routing.KeyForPublicKey(p)

	val, err := dht.GetValue(ctxT, pkkey)
	if err != nil {
		log.Warning("Failed to find requested public key.")
		return nil, err
	}

	pk, err = ci.UnmarshalPublicKey(val)
	if err != nil {
		log.Debugf("Failed to unmarshal public key: %s", err)
		return nil, err
	}

	return pk, dht.peerstore.AddPubKey(p, pk)
}