netbird/client/internal/routemanager/server_nonandroid.go
Givi Khojanashvili 246abda46d
Add default firewall rule to allow netbird traffic (#1056)
Add a default firewall rule to allow netbird traffic to be handled 
by the access control managers.

Userspace manager behavior:
- When running on Windows, a default rule is add on Windows firewall
- For Linux, we are using one of the Kernel managers to add a single rule
- This PR doesn't handle macOS

Kernel manager behavior:
- For NFtables, if there is a filter table, an INPUT rule is added
- Iptables follows the previous flow if running on kernel mode. If running 
on userspace mode, it adds a single rule for INPUT and OUTPUT chains

A new checkerFW package has been introduced to consolidate checks across
route and access control managers.
It supports a new environment variable to skip nftables and allow iptables tests
2023-09-05 21:07:32 +02:00

126 lines
2.8 KiB
Go

//go:build !android
package routemanager
import (
"context"
"fmt"
"sync"
log "github.com/sirupsen/logrus"
"github.com/netbirdio/netbird/iface"
"github.com/netbirdio/netbird/route"
)
type defaultServerRouter struct {
mux sync.Mutex
ctx context.Context
routes map[string]*route.Route
firewall firewallManager
wgInterface *iface.WGIface
}
func newServerRouter(ctx context.Context, wgInterface *iface.WGIface) (serverRouter, error) {
firewall, err := newFirewall(ctx)
if err != nil {
return nil, err
}
return &defaultServerRouter{
ctx: ctx,
routes: make(map[string]*route.Route),
firewall: firewall,
wgInterface: wgInterface,
}, nil
}
func (m *defaultServerRouter) updateRoutes(routesMap map[string]*route.Route) error {
serverRoutesToRemove := make([]string, 0)
if len(routesMap) > 0 {
err := m.firewall.RestoreOrCreateContainers()
if err != nil {
return fmt.Errorf("couldn't initialize firewall containers, got err: %v", err)
}
}
for routeID := range m.routes {
update, found := routesMap[routeID]
if !found || !update.IsEqual(m.routes[routeID]) {
serverRoutesToRemove = append(serverRoutesToRemove, routeID)
}
}
for _, routeID := range serverRoutesToRemove {
oldRoute := m.routes[routeID]
err := m.removeFromServerNetwork(oldRoute)
if err != nil {
log.Errorf("unable to remove route id: %s, network %s, from server, got: %v",
oldRoute.ID, oldRoute.Network, err)
}
delete(m.routes, routeID)
}
for id, newRoute := range routesMap {
_, found := m.routes[id]
if found {
continue
}
err := m.addToServerNetwork(newRoute)
if err != nil {
log.Errorf("unable to add route %s from server, got: %v", newRoute.ID, err)
continue
}
m.routes[id] = newRoute
}
if len(m.routes) > 0 {
err := enableIPForwarding()
if err != nil {
return err
}
}
return nil
}
func (m *defaultServerRouter) removeFromServerNetwork(route *route.Route) error {
select {
case <-m.ctx.Done():
log.Infof("not removing from server network because context is done")
return m.ctx.Err()
default:
m.mux.Lock()
defer m.mux.Unlock()
err := m.firewall.RemoveRoutingRules(routeToRouterPair(m.wgInterface.Address().String(), route))
if err != nil {
return err
}
delete(m.routes, route.ID)
return nil
}
}
func (m *defaultServerRouter) addToServerNetwork(route *route.Route) error {
select {
case <-m.ctx.Done():
log.Infof("not adding to server network because context is done")
return m.ctx.Err()
default:
m.mux.Lock()
defer m.mux.Unlock()
err := m.firewall.InsertRoutingRules(routeToRouterPair(m.wgInterface.Address().String(), route))
if err != nil {
return err
}
m.routes[route.ID] = route
return nil
}
}
func (m *defaultServerRouter) cleanUp() {
m.firewall.CleanRoutingRules()
}