Exemplo n.º 1
0
func routeHandle(route *Route, req *nl.NetlinkRequest) error {
	if (route.Dst == nil || route.Dst.IP == nil) && route.Src == nil && route.Gw == nil {
		return fmt.Errorf("one of Dst.IP, Src, or Gw must not be nil")
	}

	msg := nl.NewRtMsg()
	msg.Scope = uint8(route.Scope)
	family := -1
	var rtAttrs []*nl.RtAttr

	if route.Dst != nil && route.Dst.IP != nil {
		dstLen, _ := route.Dst.Mask.Size()
		msg.Dst_len = uint8(dstLen)
		dstFamily := nl.GetIPFamily(route.Dst.IP)
		family = dstFamily
		var dstData []byte
		if dstFamily == FAMILY_V4 {
			dstData = route.Dst.IP.To4()
		} else {
			dstData = route.Dst.IP.To16()
		}
		rtAttrs = append(rtAttrs, nl.NewRtAttr(syscall.RTA_DST, dstData))
	}

	if route.Src != nil {
		srcFamily := nl.GetIPFamily(route.Src)
		if family != -1 && family != srcFamily {
			return fmt.Errorf("source and destination ip are not the same IP family")
		}
		family = srcFamily
		var srcData []byte
		if srcFamily == FAMILY_V4 {
			srcData = route.Src.To4()
		} else {
			srcData = route.Src.To16()
		}
		// The commonly used src ip for routes is actually PREFSRC
		rtAttrs = append(rtAttrs, nl.NewRtAttr(syscall.RTA_PREFSRC, srcData))
	}

	if route.Gw != nil {
		gwFamily := nl.GetIPFamily(route.Gw)
		if family != -1 && family != gwFamily {
			return fmt.Errorf("gateway, source, and destination ip are not the same IP family")
		}
		family = gwFamily
		var gwData []byte
		if gwFamily == FAMILY_V4 {
			gwData = route.Gw.To4()
		} else {
			gwData = route.Gw.To16()
		}
		rtAttrs = append(rtAttrs, nl.NewRtAttr(syscall.RTA_GATEWAY, gwData))
	}

	msg.Family = uint8(family)

	req.AddData(msg)
	for _, attr := range rtAttrs {
		req.AddData(attr)
	}

	var (
		b      = make([]byte, 4)
		native = nl.NativeEndian()
	)
	native.PutUint32(b, uint32(route.LinkIndex))

	req.AddData(nl.NewRtAttr(syscall.RTA_OIF, b))

	_, err := req.Execute(syscall.NETLINK_ROUTE, 0)
	return err
}
Exemplo n.º 2
0
// RouteAdd will add a route to the system.
// Equivalent to: `ip route add $route`
func RouteAdd(route *Route) error {
	req := nl.NewNetlinkRequest(syscall.RTM_NEWROUTE, syscall.NLM_F_CREATE|syscall.NLM_F_EXCL|syscall.NLM_F_ACK)
	return routeHandle(route, req, nl.NewRtMsg())
}