tailscale/wgengine/router/router.go
David Anderson 89198b1691 wgengine/router: rewrite netfilter and routing logic.
New logic installs precise filters for subnet routes,
plays nice with other users of netfilter, and lays the
groundwork for fixing routing loops via policy routing.

Signed-off-by: David Anderson <danderson@tailscale.com>
2020-05-06 22:13:38 +00:00

60 lines
1.8 KiB
Go

// Copyright (c) 2020 Tailscale Inc & AUTHORS All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package router presents an interface to manipulate the host network
// stack's state.
package router
import (
"fmt"
"github.com/tailscale/wireguard-go/device"
"github.com/tailscale/wireguard-go/tun"
"github.com/tailscale/wireguard-go/wgcfg"
"tailscale.com/types/logger"
)
// Router is responsible for managing the system network stack.
//
// There is typically only one instance of this interface per process.
type Router interface {
// Up brings the router up.
Up() error
// SetRoutes is called regularly on network map updates.
// It's how you kernel route table entries are populated for
// each peer.
SetRoutes(RouteSettings) error
// Close closes the router.
Close() error
}
// New returns a new Router for the current platform, using the
// provided tun device.
func New(logf logger.Logf, wgdev *device.Device, tundev tun.Device) (Router, error) {
return newUserspaceRouter(logf, wgdev, tundev)
}
// RouteSettings is the full WireGuard config data (set of peers keys,
// IP, etc in wgcfg.Config) plus the things that WireGuard doesn't do
// itself, like DNS stuff.
type RouteSettings struct {
LocalAddr wgcfg.CIDR // TODO: why is this here? how does it differ from wgcfg.Config's info?
DNS []wgcfg.IP
DNSDomains []string
SubnetRoutes []wgcfg.CIDR // subnets being advertised to other Tailscale nodes
Cfg *wgcfg.Config
}
// OnlyRelevantParts returns a string minimally describing the route settings.
func (rs *RouteSettings) OnlyRelevantParts() string {
var peers [][]wgcfg.CIDR
for _, p := range rs.Cfg.Peers {
peers = append(peers, p.AllowedIPs)
}
return fmt.Sprintf("%v %v %v %v %v",
rs.LocalAddr, rs.DNS, rs.DNSDomains, rs.SubnetRoutes, peers)
}