tsaddr

Documentation

Overview

Package tsaddr handles Tailscale-specific IPs and ranges.

Index

• Constants
• func AllIPv4() netip.Prefix
• func AllIPv6() netip.Prefix
• func CGNATRange() netip.Prefix
• func ChromeOSVMRange() netip.Prefix
• func ContainsExitRoutes(rr views.Slice[netip.Prefix]) bool
• func ContainsNonExitSubnetRoutes(rr views.Slice[netip.Prefix]) bool
• func ExitRoutes() []netip.Prefix
• func FilterPrefixesCopy(in views.Slice[netip.Prefix], f func(netip.Prefix) bool) []netip.Prefix
• func IsTailscaleIP(ip netip.Addr) bool
• func IsViaPrefix(p netip.Prefix) bool
• func MapVia(siteID uint32, v4 netip.Prefix) (via netip.Prefix, err error)
• func NewContainsIPFunc(addrs []netip.Prefix) func(ip netip.Addr) bool
• func PrefixIs4(p netip.Prefix) bool
• func PrefixIs6(p netip.Prefix) bool
• func PrefixesContainsIP(ipp []netip.Prefix, ip netip.Addr) bool
• func SortPrefixes(p []netip.Prefix)
• func Tailscale4To6(ipv4 netip.Addr) netip.Addr
• func Tailscale4To6Placeholder() netip.Addr
• func Tailscale4To6Range() netip.Prefix
• func Tailscale6to4(ipv6 netip.Addr) (netip.Addr, bool)
• func TailscaleEphemeral6Range() netip.Prefix
• func TailscaleServiceIP() netip.Addr
• func TailscaleServiceIPv6() netip.Addr
• func TailscaleULARange() netip.Prefix
• func TailscaleViaRange() netip.Prefix
• func UnmapVia(ip netip.Addr) netip.Addr

Constants

const (
	TailscaleServiceIPString   = "100.100.100.100"
	TailscaleServiceIPv6String = "fd7a:115c:a1e0::53"
)

Functions

func AllIPv4

func AllIPv4() netip.Prefix

AllIPv4 returns 0.0.0.0/0.

func AllIPv6

func AllIPv6() netip.Prefix

AllIPv6 returns ::/0.

func CGNATRange

func CGNATRange() netip.Prefix

CGNATRange returns the Carrier Grade NAT address range that is the superset range that Tailscale assigns out of. See https://tailscale.com/s/cgnat Note that Tailscale does not assign out of the ChromeOSVMRange.

func ChromeOSVMRange

func ChromeOSVMRange() netip.Prefix

ChromeOSVMRange returns the subset of the CGNAT IPv4 range used by ChromeOS to interconnect the host OS to containers and VMs. We avoid allocating Tailscale IPs from it, to avoid conflicts.

func ContainsExitRoutes

func ContainsExitRoutes(rr views.Slice[netip.Prefix]) bool

ContainsExitRoutes reports whether rr contains both the IPv4 and IPv6 /0 route.

func ContainsNonExitSubnetRoutes

func ContainsNonExitSubnetRoutes(rr views.Slice[netip.Prefix]) bool

ContainsNonExitSubnetRoutes reports whether v contains Subnet Routes other than ExitNode Routes.

func ExitRoutes

func ExitRoutes() []netip.Prefix

ExitRoutes returns a slice containing AllIPv4 and AllIPv6.

func FilterPrefixesCopy

func FilterPrefixesCopy(in views.Slice[netip.Prefix], f func(netip.Prefix) bool) []netip.Prefix

FilterPrefixes returns a new slice, not aliasing in, containing elements of in that match f.

func IsTailscaleIP

func IsTailscaleIP(ip netip.Addr) bool

IsTailscaleIP reports whether ip is an IP address in a range that Tailscale assigns from.

func IsViaPrefix

func IsViaPrefix(p netip.Prefix) bool

IsViaPrefix reports whether p is a CIDR in the Tailscale "via" range. See TailscaleViaRange.

func MapVia

func MapVia(siteID uint32, v4 netip.Prefix) (via netip.Prefix, err error)

MapVia returns an IPv6 "via" route for an IPv4 CIDR in a given siteID.

func NewContainsIPFunc

func NewContainsIPFunc(addrs []netip.Prefix) func(ip netip.Addr) bool

NewContainsIPFunc returns a func that reports whether ip is in addrs.

It's optimized for the cases of addrs being empty and addrs containing 1 or 2 single-IP prefixes (such as one IPv4 address and one IPv6 address).

Otherwise the implementation is somewhat slow.

func PrefixIs4

func PrefixIs4(p netip.Prefix) bool

PrefixIs4 reports whether p is an IPv4 prefix.

func PrefixIs6

func PrefixIs6(p netip.Prefix) bool

PrefixIs6 reports whether p is an IPv6 prefix.

func PrefixesContainsIP

func PrefixesContainsIP(ipp []netip.Prefix, ip netip.Addr) bool

PrefixesContainsIP reports whether any prefix in ipp contains ip.

func SortPrefixes

func SortPrefixes(p []netip.Prefix)

SortPrefixes sorts the prefixes in place.

func Tailscale4To6

func Tailscale4To6(ipv4 netip.Addr) netip.Addr

Tailscale4To6 returns a Tailscale IPv6 address that maps 1:1 to the given Tailscale IPv4 address. Returns a zero IP if ipv4 isn't a Tailscale IPv4 address.

func Tailscale4To6Placeholder

func Tailscale4To6Placeholder() netip.Addr

Tailscale4To6Placeholder returns an IP address that can be used as a source IP when one is required, but a netmap didn't provide any. This address never gets allocated by the 4-to-6 algorithm in control.

Currently used to work around a Windows limitation when programming IPv6 routes in corner cases.

func Tailscale4To6Range

func Tailscale4To6Range() netip.Prefix

Tailscale4To6Range returns the subset of TailscaleULARange used for auto-translated Tailscale ipv4 addresses.

func Tailscale6to4

func Tailscale6to4(ipv6 netip.Addr) (netip.Addr, bool)

Tailscale6to4 returns the IPv4 address corresponding to the given tailscale IPv6 address within the 4To6 range. The IPv4 address and true are returned if the given address was in the correct range, false if not.

func TailscaleEphemeral6Range

func TailscaleEphemeral6Range() netip.Prefix

TailscaleEphemeral6Range returns the subset of TailscaleULARange used for ephemeral IPv6-only Tailscale nodes.

func TailscaleServiceIP

func TailscaleServiceIP() netip.Addr

TailscaleServiceIP returns the IPv4 listen address of services provided by Tailscale itself such as the MagicDNS proxy.

For IPv6, use TailscaleServiceIPv6.

func TailscaleServiceIPv6

func TailscaleServiceIPv6() netip.Addr

TailscaleServiceIPv6 returns the IPv6 listen address of the services provided by Tailscale itself such as the MagicDNS proxy.

For IPv4, use TailscaleServiceIP.

func TailscaleULARange

func TailscaleULARange() netip.Prefix

TailscaleULARange returns the IPv6 Unique Local Address range that is the superset range that Tailscale assigns out of.

func TailscaleViaRange

func TailscaleViaRange() netip.Prefix

TailscaleViaRange returns the IPv6 Unique Local Address subset range TailscaleULARange that's used for IPv4 tunneling via IPv6.

func UnmapVia

func UnmapVia(ip netip.Addr) netip.Addr

UnmapVia returns the IPv4 address that corresponds to the provided Tailscale "via" IPv4-in-IPv6 address.

If ip is not a via address, it returns ip unchanged.