netcheck

Documentation

Overview

Package netcheck checks the network conditions from the current host.

Index

• type Client
  • func (c *Client) GetReport(ctx context.Context, dm *tailcfg.DERPMap) (_ *Report, reterr error)
  • func (c *Client) MakeNextReportFull()
  • func (c *Client) ReceiveSTUNPacket(pkt []byte, src netip.AddrPort)
• type Report
  • func (r *Report) AnyPortMappingChecked() bool
  • func (r *Report) Clone() *Report
• type STUNConn

Types

type Client

type Client struct {
	// Verbose enables verbose logging.
	Verbose bool

	// Logf optionally specifies where to log to.
	// If nil, log.Printf is used.
	Logf logger.Logf

	// TimeNow, if non-nil, is used instead of time.Now.
	TimeNow func() time.Time

	// GetSTUNConn4 optionally provides a func to return the
	// connection to use for sending & receiving IPv4 packets. If
	// nil, an ephemeral one is created as needed.
	GetSTUNConn4 func() STUNConn

	// GetSTUNConn6 is like GetSTUNConn4, but for IPv6.
	GetSTUNConn6 func() STUNConn

	// SkipExternalNetwork controls whether the client should not try
	// to reach things other than localhost. This is set to true
	// in tests to avoid probing the local LAN's router, etc.
	SkipExternalNetwork bool

	// UDPBindAddr, if non-empty, is the address to listen on for UDP.
	// It defaults to ":0".
	UDPBindAddr string

	// PortMapper, if non-nil, is used for portmap queries.
	// If nil, portmap discovery is not done.
	PortMapper *portmapper.Client // lazily initialized on first use
	// contains filtered or unexported fields
}

Client generates a netcheck Report.

func (*Client) GetReport

func (c *Client) GetReport(ctx context.Context, dm *tailcfg.DERPMap) (_ *Report, reterr error)

GetReport gets a report.

It may not be called concurrently with itself.

func (*Client) MakeNextReportFull

func (c *Client) MakeNextReportFull()

MakeNextReportFull forces the next GetReport call to be a full (non-incremental) probe of all DERP regions.

func (*Client) ReceiveSTUNPacket

func (c *Client) ReceiveSTUNPacket(pkt []byte, src netip.AddrPort)

type Report

type Report struct {
	UDP         bool // a UDP STUN round trip completed
	IPv6        bool // an IPv6 STUN round trip completed
	IPv4        bool // an IPv4 STUN round trip completed
	IPv6CanSend bool // an IPv6 packet was able to be sent
	IPv4CanSend bool // an IPv4 packet was able to be sent
	OSHasIPv6   bool // could bind a socket to ::1
	ICMPv4      bool // an ICMPv4 round trip completed

	// MappingVariesByDestIP is whether STUN results depend which
	// STUN server you're talking to (on IPv4).
	MappingVariesByDestIP opt.Bool

	// HairPinning is whether the router supports communicating
	// between two local devices through the NATted public IP address
	// (on IPv4).
	HairPinning opt.Bool

	// UPnP is whether UPnP appears present on the LAN.
	// Empty means not checked.
	UPnP opt.Bool
	// PMP is whether NAT-PMP appears present on the LAN.
	// Empty means not checked.
	PMP opt.Bool
	// PCP is whether PCP appears present on the LAN.
	// Empty means not checked.
	PCP opt.Bool

	PreferredDERP   int                   // or 0 for unknown
	RegionLatency   map[int]time.Duration // keyed by DERP Region ID
	RegionV4Latency map[int]time.Duration // keyed by DERP Region ID
	RegionV6Latency map[int]time.Duration // keyed by DERP Region ID

	GlobalV4 string // ip:port of global IPv4
	GlobalV6 string // [ip]:port of global IPv6

	// CaptivePortal is set when we think there's a captive portal that is
	// intercepting HTTP traffic.
	CaptivePortal opt.Bool
}

func (*Report) AnyPortMappingChecked

func (r *Report) AnyPortMappingChecked() bool

AnyPortMappingChecked reports whether any of UPnP, PMP, or PCP are non-empty.

func (*Report) Clone

func (r *Report) Clone() *Report

type STUNConn

type STUNConn interface {
	WriteToUDPAddrPort([]byte, netip.AddrPort) (int, error)
	WriteTo([]byte, net.Addr) (int, error)
	ReadFrom([]byte) (int, net.Addr, error)
}

STUNConn is the interface required by the netcheck Client when reusing an existing UDP connection.