router

Documentation

Overview

Package router presents an interface to manipulate the host network stack's state.

Index

• Variables
• func Cleanup(logf logger.Logf, interfaceName string)
• type Config
• type DNSConfig
  • func (lhs DNSConfig) EquivalentTo(rhs DNSConfig) bool
• type NetfilterMode
  • func (m NetfilterMode) String() string
• type Router
  • func New(logf logger.Logf, wgdev *device.Device, tundev tun.Device) (Router, error)
  • func NewFake(logf logger.Logf, _ *device.Device, _ tun.Device) (Router, error)

Variables

var SetRoutesFunc func(cfg *Config) error

SetRoutesFunc applies the given router settings to the OS network stack. cfg is guaranteed to be non-nil.

This is logically part of the router_darwin.go implementation, and should not be used on other platforms.

The code to reconfigure the network stack on MacOS and iOS is in the non-open `ipn-go-bridge` package, which bridges between the Go and Swift pieces of the application. The ipn-go-bridge sets SetRoutesFunc at startup.

So why isn't this in router_darwin.go? Because in the non-oss repository, we build ipn-go-bridge when developing on Linux as well as MacOS, so that we don't have to wait until the Mac CI to discover that we broke it. So this one definition needs to exist in both the darwin and linux builds. Hence this file and build tag.

Functions

func Cleanup

func Cleanup(logf logger.Logf, interfaceName string)

Cleanup restores the system network configuration to its original state in case the Tailscale daemon terminated without closing the router. No other state needs to be instantiated before this runs.

Types

type Config

type Config struct {
	LocalAddrs []netaddr.IPPrefix
	Routes     []netaddr.IPPrefix // routes to point into the Tailscale interface

	DNSConfig

	SubnetRoutes     []netaddr.IPPrefix // subnets being advertised to other Tailscale nodes
	SNATSubnetRoutes bool               // SNAT traffic to local subnets
	NetfilterMode    NetfilterMode      // how much to manage netfilter rules
}

Config is the subset of Tailscale configuration that is relevant to the OS's network stack.

type DNSConfig

type DNSConfig struct {
	// Nameservers are the IP addresses of the nameservers to use.
	Nameservers []netaddr.IP
	// Domains are the search domains to use.
	Domains []string
}

DNSConfig is the subset of Config that contains DNS parameters.

func (DNSConfig) EquivalentTo

func (lhs DNSConfig) EquivalentTo(rhs DNSConfig) bool

EquivalentTo determines whether its argument and receiver represent equivalent DNS configurations (then DNS reconfig is a no-op).

type NetfilterMode

type NetfilterMode int

NetfilterMode is the firewall management mode to use when programming the Linux network stack.

const (
	NetfilterOff      NetfilterMode = iota // remove all tailscale netfilter state
	NetfilterNoDivert                      // manage tailscale chains, but don't call them
	NetfilterOn                            // manage tailscale chains and call them from main chains
)

func (NetfilterMode) String

func (m NetfilterMode) String() string

type Router

type Router interface {
	// Up brings the router up.
	Up() error

	// Set updates the OS network stack with a new Config. It may be
	// called multiple times with identical Configs, which the
	// implementation should handle gracefully.
	Set(*Config) error

	// Close closes the router.
	Close() error
}

Router is responsible for managing the system network stack.

There is typically only one instance of this interface per process.

func New

func New(logf logger.Logf, wgdev *device.Device, tundev tun.Device) (Router, error)

New returns a new Router for the current platform, using the provided tun device.

func NewFake

func NewFake(logf logger.Logf, _ *device.Device, _ tun.Device) (Router, error)

NewFakeRouter returns a Router that does nothing when called and always returns nil errors.