diff options
Diffstat (limited to 'pkg/tcpip/stack/route.go')
| -rw-r--r-- | pkg/tcpip/stack/route.go | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/pkg/tcpip/stack/route.go b/pkg/tcpip/stack/route.go index 5c8b7977a..0b09e6517 100644 --- a/pkg/tcpip/stack/route.go +++ b/pkg/tcpip/stack/route.go @@ -59,6 +59,8 @@ func makeRoute(netProto tcpip.NetworkProtocolNumber, localAddr, remoteAddr tcpip loop = PacketLoop } else if multicastLoop && (header.IsV4MulticastAddress(remoteAddr) || header.IsV6MulticastAddress(remoteAddr)) { loop |= PacketLoop + } else if remoteAddr == header.IPv4Broadcast { + loop |= PacketLoop } return Route{ @@ -208,10 +210,17 @@ func (r *Route) Clone() Route { return *r } -// MakeLoopedRoute duplicates the given route and tweaks it in case of multicast. +// MakeLoopedRoute duplicates the given route with special handling for routes +// used for sending multicast or broadcast packets. In those cases the +// multicast/broadcast address is the remote address when sending out, but for +// incoming (looped) packets it becomes the local address. Similarly, the local +// interface address that was the local address going out becomes the remote +// address coming in. This is different to unicast routes where local and +// remote addresses remain the same as they identify location (local vs remote) +// not direction (source vs destination). func (r *Route) MakeLoopedRoute() Route { l := r.Clone() - if header.IsV4MulticastAddress(r.RemoteAddress) || header.IsV6MulticastAddress(r.RemoteAddress) { + if r.RemoteAddress == header.IPv4Broadcast || header.IsV4MulticastAddress(r.RemoteAddress) || header.IsV6MulticastAddress(r.RemoteAddress) { l.RemoteAddress, l.LocalAddress = l.LocalAddress, l.RemoteAddress l.RemoteLinkAddress = l.LocalLinkAddress } |