Method acquireNewLocked

lib/nat/service.go:276–318

(ctx context.Context, mapping *Mapping, nats map[string]Device)

}

func (s *Service) acquireNewLocked(ctx context.Context, mapping *Mapping, nats map[string]Device) (change bool) {
	leaseTime := time.Duration(s.cfg.Options().NATLeaseM) * time.Minute
	addrMap := mapping.extAddresses

	for id, nat := range nats {
		select {
		case <-ctx.Done():
			return false
		default:
		}

		if _, ok := addrMap[id]; ok {
			continue
		}

		// Only perform mappings on the nat's that have the right local IP
		// address
		localIP := nat.GetLocalIPv4Address()
		if !mapping.validGateway(localIP) && nat.SupportsIPVersion(IPv4Only) {
			l.Debugf("Skipping %s for %s because of IP mismatch. %s != %s", id, mapping, mapping.address.IP, localIP)
			continue
		}

		l.Debugf("Trying to open port %s on %s", mapping, id)

		if !nat.SupportsIPVersion(mapping.ipVersion) {
			l.Debugf("Skipping firewall traversal on gateway %s because it doesn't match the listener address family", nat.ID())
			continue
		}

		addrs, err := s.tryNATDevice(ctx, nat, mapping.address, 0, mapping.protocol, leaseTime)
		if err != nil {
			slog.WarnContext(ctx, "Failed to acquire open port", slog.String("mapping", mapping.String()), slog.String("id", id), slogutil.Error(err))
			continue
		}

		l.Debugf("Opened port %s -> %v on %s", mapping, addrs, id)
		mapping.setAddressLocked(id, addrs)
		change = true
	}

	return change
}

// tryNATDevice tries to acquire a port mapping for the given internal address to
// the given external port. If external port is 0, picks a pseudo-random port.