net/tstun: add inital support for NAT v4

This adds support in tstun to utitilize the SelfNodeV4MasqAddrForThisPeer and perform the necessary modifications to the packet as it passes through tstun. Currently this only handles ICMP, UDP and TCP traffic. Subnet routers and Exit Nodes are also unsupported. Updates tailscale/corp#8020 Co-authored-by: Melanie Warrick <warrick@tailscale.com> Signed-off-by: Maisem Ali <maisem@tailscale.com>
2023-03-23 16:54:12 -07:00
parent 535fad16f8
commit bb31fd7d1c
4 changed files with 384 additions and 7 deletions
@@ -1205,6 +1205,7 @@ func (e *userspaceEngine) SetNetworkMap(nm *netmap.NetworkMap) {
 	e.magicConn.SetNetworkMap(nm)
 	e.mu.Lock()
 	e.netMap = nm
+	e.tundev.SetNetMap(nm)
 	callbacks := make([]NetworkMapCallback, 0, 4)
 	for _, fn := range e.networkMapCallbacks {
 		callbacks = append(callbacks, fn)