@ -7,6 +7,7 @@ package ipn
import (
"bytes"
"encoding/json"
"errors"
"fmt"
"io/ioutil"
"log"
@ -18,10 +19,12 @@ import (
"inet.af/netaddr"
"tailscale.com/atomicfile"
"tailscale.com/ipn/ipnstate"
"tailscale.com/net/tsaddr"
"tailscale.com/tailcfg"
"tailscale.com/types/persist"
"tailscale.com/types/preftype"
"tailscale.com/util/dnsname"
)
//go:generate go run tailscale.com/cmd/cloner -type=Prefs -output=prefs_clone.go
@ -31,6 +34,12 @@ import (
// The default control plane is the hosted version run by Tailscale.com.
const DefaultControlURL = "https://controlplane.tailscale.com"
var (
// ErrExitNodeIDAlreadySet is returned from (*Prefs).SetExitNodeIP when the
// Prefs.ExitNodeID field is already set.
ErrExitNodeIDAlreadySet = errors . New ( "cannot set ExitNodeIP when ExitNodeID is already set" )
)
// IsLoginServerSynonym reports whether a URL is a drop-in replacement
// for the primary Tailscale login server.
func IsLoginServerSynonym ( val interface { } ) bool {
@ -467,6 +476,109 @@ func (p *Prefs) SetAdvertiseExitNode(runExit bool) {
netaddr . IPPrefixFrom ( netaddr . IPv6Unspecified ( ) , 0 ) )
}
// peerWithTailscaleIP returns the peer in st with the provided
// Tailscale IP.
func peerWithTailscaleIP ( st * ipnstate . Status , ip netaddr . IP ) ( ps * ipnstate . PeerStatus , ok bool ) {
for _ , ps := range st . Peer {
for _ , ip2 := range ps . TailscaleIPs {
if ip == ip2 {
return ps , true
}
}
}
return nil , false
}
func isRemoteIP ( st * ipnstate . Status , ip netaddr . IP ) bool {
for _ , selfIP := range st . TailscaleIPs {
if ip == selfIP {
return false
}
}
return true
}
// ClearExitNode sets the ExitNodeID and ExitNodeIP to their zero values.
func ( p * Prefs ) ClearExitNode ( ) {
p . ExitNodeID = ""
p . ExitNodeIP = netaddr . IP { }
}
// ExitNodeLocalIPError is returned when the requested IP address for an exit
// node belongs to the local machine.
type ExitNodeLocalIPError struct {
hostOrIP string
}
func ( e ExitNodeLocalIPError ) Error ( ) string {
return fmt . Sprintf ( "cannot use %s as an exit node as it is a local IP address to this machine" , e . hostOrIP )
}
func exitNodeIPOfArg ( s string , st * ipnstate . Status ) ( ip netaddr . IP , err error ) {
if s == "" {
return ip , os . ErrInvalid
}
ip , err = netaddr . ParseIP ( s )
if err == nil {
// If we're online already and have a netmap, double check that the IP
// address specified is valid.
if st . BackendState == "Running" {
ps , ok := peerWithTailscaleIP ( st , ip )
if ! ok {
return ip , fmt . Errorf ( "no node found in netmap with IP %v" , ip )
}
if ! ps . ExitNodeOption {
return ip , fmt . Errorf ( "node %v is not advertising an exit node" , ip )
}
}
if ! isRemoteIP ( st , ip ) {
return ip , ExitNodeLocalIPError { s }
}
return ip , nil
}
match := 0
for _ , ps := range st . Peer {
baseName := dnsname . TrimSuffix ( ps . DNSName , st . MagicDNSSuffix )
if ! strings . EqualFold ( s , baseName ) {
continue
}
match ++
if len ( ps . TailscaleIPs ) == 0 {
return ip , fmt . Errorf ( "node %q has no Tailscale IP?" , s )
}
if ! ps . ExitNodeOption {
return ip , fmt . Errorf ( "node %q is not advertising an exit node" , s )
}
ip = ps . TailscaleIPs [ 0 ]
}
switch match {
case 0 :
return ip , fmt . Errorf ( "invalid value %q for --exit-node; must be IP or unique node name" , s )
case 1 :
if ! isRemoteIP ( st , ip ) {
return ip , ExitNodeLocalIPError { s }
}
return ip , nil
default :
return ip , fmt . Errorf ( "ambiguous exit node name %q" , s )
}
}
// SetExitNodeIP validates and sets the ExitNodeIP from a user-provided string
// specifying either an IP address or a MagicDNS base name ("foo", as opposed to
// "foo.bar.beta.tailscale.net"). This method does not mutate ExitNodeID and
// will fail if ExitNodeID is already set.
func ( p * Prefs ) SetExitNodeIP ( s string , st * ipnstate . Status ) error {
if ! p . ExitNodeID . IsZero ( ) {
return ErrExitNodeIDAlreadySet
}
ip , err := exitNodeIPOfArg ( s , st )
if err == nil {
p . ExitNodeIP = ip
}
return err
}
// PrefsFromBytes deserializes Prefs from a JSON blob. If
// enforceDefaults is true, Prefs.RouteAll and Prefs.AllowSingleHosts
// are forced on.
Aaron Klotz
3 years ago