You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
tailscale/tstest/natlab/vnet/vip.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
}