net/tsdial: start of new package to unify all outbound dialing complexity

For now this just deletes the net/socks5/tssocks implementation (and
the DNSMap stuff from wgengine/netstack) and moves it into net/tsdial.

Then initialize a Dialer early in tailscaled, currently only use for the
outbound and SOCKS5 proxies. It will be plumbed more later. Notably, it
needs to get down into the DNS forwarder for exit node DNS forwading
in netstack mode. But it will also absorb all the peerapi setsockopt
and netns Dial and tlsdial complexity too.

Updates #1713

Change-Id: Ibc6d56ae21a22655b2fa1002d8fc3f2b2ae8b6df
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This commit is contained in:
Brad Fitzpatrick
2021-11-30 15:53:34 -08:00
committed by Brad Fitzpatrick
parent 3ae6f898cf
commit d5405c66b7
12 changed files with 221 additions and 198 deletions

View File

@@ -33,10 +33,10 @@ import (
"inet.af/netstack/waiter"
"tailscale.com/net/packet"
"tailscale.com/net/tsaddr"
"tailscale.com/net/tsdial"
"tailscale.com/net/tstun"
"tailscale.com/types/logger"
"tailscale.com/types/netmap"
"tailscale.com/util/dnsname"
"tailscale.com/wgengine"
"tailscale.com/wgengine/filter"
"tailscale.com/wgengine/magicsock"
@@ -79,7 +79,7 @@ type Impl struct {
atomicIsLocalIPFunc atomic.Value // of func(netaddr.IP) bool
mu sync.Mutex
dns DNSMap
dns tsdial.DNSMap
// connsOpenBySubnetIP keeps track of number of connections open
// for each subnet IP temporarily registered on netstack for active
// TCP connections, so they can be unregistered when connections are
@@ -179,59 +179,10 @@ func (ns *Impl) Start() error {
return nil
}
// DNSMap maps MagicDNS names (both base + FQDN) to their first IP.
// It should not be mutated once created.
type DNSMap map[string]netaddr.IP
func DNSMapFromNetworkMap(nm *netmap.NetworkMap) DNSMap {
ret := make(DNSMap)
suffix := nm.MagicDNSSuffix()
have4 := false
if nm.Name != "" && len(nm.Addresses) > 0 {
ip := nm.Addresses[0].IP()
ret[strings.TrimRight(nm.Name, ".")] = ip
if dnsname.HasSuffix(nm.Name, suffix) {
ret[dnsname.TrimSuffix(nm.Name, suffix)] = ip
}
for _, a := range nm.Addresses {
if a.IP().Is4() {
have4 = true
}
}
}
for _, p := range nm.Peers {
if p.Name == "" {
continue
}
for _, a := range p.Addresses {
ip := a.IP()
if ip.Is4() && !have4 {
continue
}
ret[strings.TrimRight(p.Name, ".")] = ip
if dnsname.HasSuffix(p.Name, suffix) {
ret[dnsname.TrimSuffix(p.Name, suffix)] = ip
}
break
}
}
for _, rec := range nm.DNS.ExtraRecords {
if rec.Type != "" {
continue
}
ip, err := netaddr.ParseIP(rec.Value)
if err != nil {
continue
}
ret[strings.TrimRight(rec.Name, ".")] = ip
}
return ret
}
func (ns *Impl) updateDNS(nm *netmap.NetworkMap) {
ns.mu.Lock()
defer ns.mu.Unlock()
ns.dns = DNSMapFromNetworkMap(nm)
ns.dns = tsdial.DNSMapFromNetworkMap(nm)
}
func (ns *Impl) addSubnetAddress(ip netaddr.IP) {
@@ -347,49 +298,6 @@ func (ns *Impl) updateIPs(nm *netmap.NetworkMap) {
}
}
// Resolve resolves addr into an IP:port using first the MagicDNS contents
// of m, else using the system resolver.
func (m DNSMap) Resolve(ctx context.Context, addr string) (netaddr.IPPort, error) {
ipp, pippErr := netaddr.ParseIPPort(addr)
if pippErr == nil {
return ipp, nil
}
host, port, err := net.SplitHostPort(addr)
if err != nil {
// addr is malformed.
return netaddr.IPPort{}, err
}
if net.ParseIP(host) != nil {
// The host part of addr was an IP, so the netaddr.ParseIPPort above should've
// passed. Must've been a bad port number. Return the original error.
return netaddr.IPPort{}, pippErr
}
port16, err := strconv.ParseUint(port, 10, 16)
if err != nil {
return netaddr.IPPort{}, fmt.Errorf("invalid port in address %q", addr)
}
// Host is not an IP, so assume it's a DNS name.
// Try MagicDNS first, else otherwise a real DNS lookup.
ip := m[host]
if !ip.IsZero() {
return netaddr.IPPortFrom(ip, uint16(port16)), nil
}
// No MagicDNS name so try real DNS.
var r net.Resolver
ips, err := r.LookupIP(ctx, "ip", host)
if err != nil {
return netaddr.IPPort{}, err
}
if len(ips) == 0 {
return netaddr.IPPort{}, fmt.Errorf("DNS lookup returned no results for %q", host)
}
ip, _ = netaddr.FromStdIP(ips[0])
return netaddr.IPPortFrom(ip, uint16(port16)), nil
}
func (ns *Impl) DialContextTCP(ctx context.Context, addr string) (*gonet.TCPConn, error) {
ns.mu.Lock()
dnsMap := ns.dns

View File

@@ -1,112 +0,0 @@
// 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 netstack
import (
"reflect"
"testing"
"inet.af/netaddr"
"tailscale.com/tailcfg"
"tailscale.com/types/netmap"
)
func TestDNSMapFromNetworkMap(t *testing.T) {
pfx := netaddr.MustParseIPPrefix
ip := netaddr.MustParseIP
tests := []struct {
name string
nm *netmap.NetworkMap
want DNSMap
}{
{
name: "self",
nm: &netmap.NetworkMap{
Name: "foo.tailnet",
Addresses: []netaddr.IPPrefix{
pfx("100.102.103.104/32"),
pfx("100::123/128"),
},
},
want: DNSMap{
"foo": ip("100.102.103.104"),
"foo.tailnet": ip("100.102.103.104"),
},
},
{
name: "self_and_peers",
nm: &netmap.NetworkMap{
Name: "foo.tailnet",
Addresses: []netaddr.IPPrefix{
pfx("100.102.103.104/32"),
pfx("100::123/128"),
},
Peers: []*tailcfg.Node{
{
Name: "a.tailnet",
Addresses: []netaddr.IPPrefix{
pfx("100.0.0.201/32"),
pfx("100::201/128"),
},
},
{
Name: "b.tailnet",
Addresses: []netaddr.IPPrefix{
pfx("100::202/128"),
},
},
},
},
want: DNSMap{
"foo": ip("100.102.103.104"),
"foo.tailnet": ip("100.102.103.104"),
"a": ip("100.0.0.201"),
"a.tailnet": ip("100.0.0.201"),
"b": ip("100::202"),
"b.tailnet": ip("100::202"),
},
},
{
name: "self_has_v6_only",
nm: &netmap.NetworkMap{
Name: "foo.tailnet",
Addresses: []netaddr.IPPrefix{
pfx("100::123/128"),
},
Peers: []*tailcfg.Node{
{
Name: "a.tailnet",
Addresses: []netaddr.IPPrefix{
pfx("100.0.0.201/32"),
pfx("100::201/128"),
},
},
{
Name: "b.tailnet",
Addresses: []netaddr.IPPrefix{
pfx("100::202/128"),
},
},
},
},
want: DNSMap{
"foo": ip("100::123"),
"foo.tailnet": ip("100::123"),
"a": ip("100::201"),
"a.tailnet": ip("100::201"),
"b": ip("100::202"),
"b.tailnet": ip("100::202"),
},
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
got := DNSMapFromNetworkMap(tt.nm)
if !reflect.DeepEqual(got, tt.want) {
t.Errorf("mismatch:\n got %v\nwant %v\n", got, tt.want)
}
})
}
}