interfaces

Documentation

Overview

Package interfaces contains helpers for looking up system network interfaces.

Index

• func ForeachInterfaceAddress(fn func(Interface, net.IP)) error
• func HTTPOfListener(ln net.Listener) string
• func HaveIPv6GlobalAddress() (bool, error)
• func IsTailscaleIP(ip net.IP) bool
• func LocalAddresses() (regular, loopback []string, err error)
• func Tailscale() (net.IP, *net.Interface, error)
• type Interface
  • func (i Interface) IsLoopback() bool
  • func (i Interface) IsUp() bool
• type State
  • func GetState() (*State, error)
  • func (s *State) Equal(s2 *State) bool
  • func (s *State) RemoveTailscaleInterfaces()

Functions

func ForeachInterfaceAddress

func ForeachInterfaceAddress(fn func(Interface, net.IP)) error

ForeachInterfaceAddress calls fn for each interface's address on the machine.

func HTTPOfListener

func HTTPOfListener(ln net.Listener) string

HTTPOfListener returns the HTTP address to ln. If the listener is listening on the unspecified address, it it tries to find a reasonable interface address on the machine to use.

func HaveIPv6GlobalAddress

func HaveIPv6GlobalAddress() (bool, error)

HaveIPv6GlobalAddress reports whether the machine appears to have a global scope unicast IPv6 address.

It only returns an error if there's a problem querying the system interfaces.

func IsTailscaleIP

func IsTailscaleIP(ip net.IP) bool

IsTailscaleIP reports whether ip is an IP in a range used by Tailscale virtual network interfaces.

func LocalAddresses

func LocalAddresses() (regular, loopback []string, err error)

LocalAddresses returns the machine's IP addresses, separated by whether they're loopback addresses.

func Tailscale

func Tailscale() (net.IP, *net.Interface, error)

Tailscale returns the current machine's Tailscale interface, if any. If none is found, all zero values are returned. A non-nil error is only returned on a problem listing the system interfaces.

Types

type Interface

type Interface struct {
	*net.Interface
}

Interface is a wrapper around Go's net.Interface with some extra methods.

func (Interface) IsLoopback

func (i Interface) IsLoopback() bool

func (Interface) IsUp

func (i Interface) IsUp() bool

type State

type State struct {
	InterfaceIPs map[string][]net.IP
	InterfaceUp  map[string]bool

	// IsExpensive is whether the current network interface is
	// considered "expensive", which currently means LTE/etc
	// instead of Wifi. This field is not populated by GetState.
	IsExpensive bool
}

State is intended to store the state of the machine's network interfaces, routing table, and other network configuration. For now it's pretty basic.

func GetState

func GetState() (*State, error)

GetState returns the state of all the current machine's network interfaces.

It does not set the returned State.IsExpensive. The caller can populate that.

func (*State) Equal

func (s *State) Equal(s2 *State) bool

func (*State) RemoveTailscaleInterfaces

func (s *State) RemoveTailscaleInterfaces()

RemoveTailscaleInterfaces modifes s to remove any interfaces that are owned by this process. (TODO: make this true; currently it makes the Linux-only assumption that the interface is named /^tailscale/)