mirror of
https://github.com/tailscale/tailscale.git
synced 2024-11-30 05:25:35 +00:00
82 lines
2.1 KiB
Go
82 lines
2.1 KiB
Go
|
// Copyright (c) Tailscale Inc & AUTHORS
|
||
|
|
// SPDX-License-Identifier: BSD-3-Clause
|
||
|
|
|
||
|
|
package vnet
|
||
|
|
|
||
|
|
import (
|
||
|
|
"fmt"
|
||
|
|
"net/netip"
|
||
|
|
)
|
||
|
|
|
||
|
|
var vips = map[string]virtualIP{} // DNS name => details
|
||
|
|
|
||
|
|
var (
|
||
|
|
fakeDNS = newVIP("dns", "4.11.4.11", "2000:4:11::4:11")
|
||
|
|
fakeProxyControlplane = newVIP("controlplane.tailscale.com", 1)
|
||
|
|
fakeTestAgent = newVIP("test-driver.tailscale", 2)
|
||
|
|
fakeControl = newVIP("control.tailscale", 3)
|
||
|
|
fakeDERP1 = newVIP("derp1.tailscale", "33.4.0.1") // 3340=DERP; 1=derp 1
|
||
|
|
fakeDERP2 = newVIP("derp2.tailscale", "33.4.0.2") // 3340=DERP; 2=derp 2
|
||
|
|
fakeLogCatcher = newVIP("log.tailscale.io", 4)
|
||
|
|
fakeSyslog = newVIP("syslog.tailscale", 9)
|
||
|
|
)
|
||
|
|
|
||
|
|
type virtualIP struct {
|
||
|
|
name string // for DNS
|
||
|
|
v4 netip.Addr
|
||
|
|
v6 netip.Addr
|
||
|
|
}
|
||
|
|
|
||
|
|
func (v virtualIP) Match(a netip.Addr) bool {
|
||
|
|
return v.v4 == a.Unmap() || v.v6 == a
|
||
|
|
}
|
||
|
|
|
||
|
|
// newVIP returns a new virtual IP.
|
||
|
|
//
|
||
|
|
// opts may be an IPv4 an IPv6 (in string form) or an int (bounded by uint8) to
|
||
|
|
// use IPv4 of 52.52.0.x.
|
||
|
|
//
|
||
|
|
// If the IPv6 is omitted, one is derived from the IPv4.
|
||
|
|
//
|
||
|
|
// If an opt is invalid or the DNS name is already used, it panics.
|
||
|
|
func newVIP(name string, opts ...any) (v virtualIP) {
|
||
|
|
if _, ok := vips[name]; ok {
|
||
|
|
panic(fmt.Sprintf("duplicate VIP %q", name))
|
||
|
|
}
|
||
|
|
v.name = name
|
||
|
|
for _, o := range opts {
|
||
|
|
switch o := o.(type) {
|
||
|
|
case string:
|
||
|
|
if ip, err := netip.ParseAddr(o); err == nil {
|
||
|
|
if ip.Is4() {
|
||
|
|
v.v4 = ip
|
||
|
|
} else if ip.Is6() {
|
||
|
|
v.v6 = ip
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
panic(fmt.Sprintf("unsupported string option %q", o))
|
||
|
|
}
|
||
|
|
case int:
|
||
|
|
if o <= 0 || o > 255 {
|
||
|
|
panic(fmt.Sprintf("bad octet %d", o))
|
||
|
|
}
|
||
|
|
v.v4 = netip.AddrFrom4([4]byte{52, 52, 0, byte(o)})
|
||
|
|
default:
|
||
|
|
panic(fmt.Sprintf("unknown option type %T", o))
|
||
|
|
}
|
||
|
|
}
|
||
|
|
if !v.v6.IsValid() && v.v4.IsValid() {
|
||
|
|
// Map 1.2.3.4 to 2052::0102:0304
|
||
|
|
a := [16]byte{0: 2, 2: 5, 3: 2} // 2052::
|
||
|
|
copy(a[12:], v.v4.AsSlice())
|
||
|
|
v.v6 = netip.AddrFrom16(a)
|
||
|
|
}
|
||
|
|
for _, b := range vips {
|
||
|
|
if b.Match(v.v4) || b.Match(v.v6) {
|
||
|
|
panic(fmt.Sprintf("VIP %q collides with %q", name, v.name))
|
||
|
|
}
|
||
|
|
}
|
||
|
|
vips[name] = v
|
||
|
|
return v
|
||
|
|
}
|