mirror of
https://github.com/tailscale/tailscale.git
synced 2024-11-30 05:25:35 +00:00
93 lines
2.9 KiB
Go
93 lines
2.9 KiB
Go
// Copyright (c) 2021 Tailscale Inc & AUTHORS All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
package dns
|
|
|
|
import (
|
|
"errors"
|
|
|
|
"inet.af/netaddr"
|
|
"tailscale.com/util/dnsname"
|
|
)
|
|
|
|
// An OSConfigurator applies DNS settings to the operating system.
|
|
type OSConfigurator interface {
|
|
// SetDNS updates the OS's DNS configuration to match cfg.
|
|
// If cfg is the zero value, all Tailscale-related DNS
|
|
// configuration is removed.
|
|
// SetDNS must not be called after Close.
|
|
SetDNS(cfg OSConfig) error
|
|
// SupportsSplitDNS reports whether the configurator is capable of
|
|
// installing a resolver only for specific DNS suffixes. If false,
|
|
// the configurator can only set a global resolver.
|
|
SupportsSplitDNS() bool
|
|
// GetBaseConfig returns the OS's "base" configuration, i.e. the
|
|
// resolver settings the OS would use without Tailscale
|
|
// contributing any configuration.
|
|
// GetBaseConfig must return the tailscale-free base config even
|
|
// after SetDNS has been called to set a Tailscale configuration.
|
|
// Only works when SupportsSplitDNS=false.
|
|
|
|
// Implementations that don't support getting the base config must
|
|
// return ErrGetBaseConfigNotSupported.
|
|
GetBaseConfig() (OSConfig, error)
|
|
// Close removes Tailscale-related DNS configuration from the OS.
|
|
Close() error
|
|
}
|
|
|
|
// OSConfig is an OS DNS configuration.
|
|
type OSConfig struct {
|
|
// Nameservers are the IP addresses of the nameservers to use.
|
|
Nameservers []netaddr.IP
|
|
// SearchDomains are the domain suffixes to use when expanding
|
|
// single-label name queries. SearchDomains is additive to
|
|
// whatever non-Tailscale search domains the OS has.
|
|
SearchDomains []dnsname.FQDN
|
|
// MatchDomains are the DNS suffixes for which Nameservers should
|
|
// be used. If empty, Nameservers is installed as the "primary" resolver.
|
|
// A non-empty MatchDomains requests a "split DNS" configuration
|
|
// from the OS, which will only work with OSConfigurators that
|
|
// report SupportsSplitDNS()=true.
|
|
MatchDomains []dnsname.FQDN
|
|
}
|
|
|
|
func (o OSConfig) IsZero() bool {
|
|
return len(o.Nameservers) == 0 && len(o.SearchDomains) == 0 && len(o.MatchDomains) == 0
|
|
}
|
|
|
|
func (a OSConfig) Equal(b OSConfig) bool {
|
|
if len(a.Nameservers) != len(b.Nameservers) {
|
|
return false
|
|
}
|
|
if len(a.SearchDomains) != len(b.SearchDomains) {
|
|
return false
|
|
}
|
|
if len(a.MatchDomains) != len(b.MatchDomains) {
|
|
return false
|
|
}
|
|
|
|
for i := range a.Nameservers {
|
|
if a.Nameservers[i] != b.Nameservers[i] {
|
|
return false
|
|
}
|
|
}
|
|
for i := range a.SearchDomains {
|
|
if a.SearchDomains[i] != b.SearchDomains[i] {
|
|
return false
|
|
}
|
|
}
|
|
for i := range a.MatchDomains {
|
|
if a.MatchDomains[i] != b.MatchDomains[i] {
|
|
return false
|
|
}
|
|
}
|
|
|
|
return true
|
|
}
|
|
|
|
// ErrGetBaseConfigNotSupported is the error
|
|
// OSConfigurator.GetBaseConfig returns when the OSConfigurator
|
|
// doesn't support reading the underlying configuration out of the OS.
|
|
var ErrGetBaseConfigNotSupported = errors.New("getting OS base config is not supported")
|