mirror of
https://github.com/tailscale/tailscale.git
synced 2024-11-25 19:15:34 +00:00
appc,ipn/ipnlocal,net/dns/resolver: add App Connector wiring when enabled in prefs
An EmbeddedAppConnector is added that when configured observes DNS responses from the PeerAPI. If a response is found matching a configured domain, routes are advertised when necessary. The wiring from a configuration in the netmap capmap is not yet done, so while the connector can be enabled, no domains can yet be added. Updates tailscale/corp#15437 Signed-off-by: James Tucker <james@tailscale.com>
This commit is contained in:
parent
e7482f0df0
commit
b48b7d82d0
@ -31,7 +31,7 @@ type target struct {
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Matching tailcfg.ProtoPortRange
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}
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// Server implements an App Connector.
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// Server implements an App Connector as expressed in sniproxy.
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type Server struct {
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mu sync.RWMutex // mu guards following fields
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connectors map[appctype.ConfigID]connector
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165
appc/embedded.go
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165
appc/embedded.go
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@ -0,0 +1,165 @@
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// Copyright (c) Tailscale Inc & AUTHORS
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// SPDX-License-Identifier: BSD-3-Clause
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// Package appc implements App Connectors. An AppConnector provides domain
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// oriented routing of traffic.
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package appc
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import (
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"net/netip"
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"slices"
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"strings"
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"sync"
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"golang.org/x/net/dns/dnsmessage"
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"tailscale.com/types/logger"
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)
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/*
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* TODO(raggi): the sniproxy servicing portions of this package will be moved
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* into the sniproxy or deprecated at some point, when doing so is not
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* disruptive. At that time EmbeddedAppConnector can be renamed to AppConnector.
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*/
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// RouteAdvertiser is an interface that allows the AppConnector to advertise
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// newly discovered routes that need to be served through the AppConnector.
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type RouteAdvertiser interface {
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// AdvertiseRoute adds a new route advertisement if the route is not already
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// being advertised.
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AdvertiseRoute(netip.Prefix) error
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}
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// EmbeddedAppConnector is an implementation of an AppConnector that performs
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// its function as a subsystem inside of a tailscale node. At the control plane
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// side App Connector routing is configured in terms of domains rather than IP
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// addresses.
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// The AppConnectors responsibility inside tailscaled is to apply the routing
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// and domain configuration as supplied in the map response.
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// DNS requests for configured domains are observed. If the domains resolve to
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// routes not yet served by the AppConnector the local node configuration is
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// updated to advertise the new route.
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type EmbeddedAppConnector struct {
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logf logger.Logf
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routeAdvertiser RouteAdvertiser
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// mu guards the fields that follow
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mu sync.Mutex
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// domains is a map of lower case domain names with no trailing dot, to a
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// list of resolved IP addresses.
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domains map[string][]netip.Addr
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}
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// NewEmbeddedAppConnector creates a new EmbeddedAppConnector.
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func NewEmbeddedAppConnector(logf logger.Logf, routeAdvertiser RouteAdvertiser) *EmbeddedAppConnector {
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return &EmbeddedAppConnector{
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logf: logger.WithPrefix(logf, "appc: "),
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routeAdvertiser: routeAdvertiser,
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}
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}
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// UpdateDomains replaces the current set of configured domains with the
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// supplied set of domains. Domains must not contain a trailing dot, and should
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// be lower case.
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func (e *EmbeddedAppConnector) UpdateDomains(domains []string) {
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e.mu.Lock()
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defer e.mu.Unlock()
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var old map[string][]netip.Addr
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old, e.domains = e.domains, make(map[string][]netip.Addr, len(domains))
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for _, d := range domains {
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d = strings.ToLower(d)
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e.domains[d] = old[d]
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}
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}
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// ObserveDNSResponse is a callback invoked by the DNS resolver when a DNS
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// response is being returned over the PeerAPI. The response is parsed and
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// matched against the configured domains, if matched the routeAdvertiser is
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// advised to advertise the discovered route.
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func (e *EmbeddedAppConnector) ObserveDNSResponse(res []byte) {
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var p dnsmessage.Parser
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if _, err := p.Start(res); err != nil {
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return
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}
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if err := p.SkipAllQuestions(); err != nil {
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return
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}
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for {
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h, err := p.AnswerHeader()
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if err == dnsmessage.ErrSectionDone {
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break
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}
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if err != nil {
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return
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}
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if h.Class != dnsmessage.ClassINET {
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if err := p.SkipAnswer(); err != nil {
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return
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}
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continue
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}
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if h.Type != dnsmessage.TypeA && h.Type != dnsmessage.TypeAAAA {
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if err := p.SkipAnswer(); err != nil {
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return
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}
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continue
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}
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domain := h.Name.String()
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if len(domain) == 0 {
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return
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}
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if domain[len(domain)-1] == '.' {
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domain = domain[:len(domain)-1]
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}
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domain = strings.ToLower(domain)
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e.logf("[v2] observed DNS response for %s", domain)
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e.mu.Lock()
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addrs, ok := e.domains[domain]
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e.mu.Unlock()
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if !ok {
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if err := p.SkipAnswer(); err != nil {
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return
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}
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continue
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}
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var addr netip.Addr
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switch h.Type {
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case dnsmessage.TypeA:
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r, err := p.AResource()
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if err != nil {
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return
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}
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addr = netip.AddrFrom4(r.A)
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case dnsmessage.TypeAAAA:
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r, err := p.AAAAResource()
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if err != nil {
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return
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}
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addr = netip.AddrFrom16(r.AAAA)
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default:
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if err := p.SkipAnswer(); err != nil {
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return
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}
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continue
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}
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if slices.Contains(addrs, addr) {
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continue
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}
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// TODO(raggi): check for existing prefixes
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if err := e.routeAdvertiser.AdvertiseRoute(netip.PrefixFrom(addr, addr.BitLen())); err != nil {
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e.logf("failed to advertise route for %v: %v", addr, err)
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continue
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}
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e.logf("[v2] advertised route for %v: %v", domain, addr)
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e.mu.Lock()
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e.domains[domain] = append(addrs, addr)
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e.mu.Unlock()
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}
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}
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118
appc/embedded_test.go
Normal file
118
appc/embedded_test.go
Normal file
@ -0,0 +1,118 @@
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// Copyright (c) Tailscale Inc & AUTHORS
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// SPDX-License-Identifier: BSD-3-Clause
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package appc
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import (
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"net/netip"
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"slices"
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"testing"
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xmaps "golang.org/x/exp/maps"
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"golang.org/x/net/dns/dnsmessage"
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"tailscale.com/util/must"
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)
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func TestUpdateDomains(t *testing.T) {
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a := NewEmbeddedAppConnector(t.Logf, nil)
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a.UpdateDomains([]string{"example.com"})
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if got, want := xmaps.Keys(a.domains), []string{"example.com"}; !slices.Equal(got, want) {
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t.Errorf("got %v; want %v", got, want)
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}
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addr := netip.MustParseAddr("192.0.0.8")
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a.domains["example.com"] = append(a.domains["example.com"], addr)
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a.UpdateDomains([]string{"example.com"})
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if got, want := a.domains["example.com"], []netip.Addr{addr}; !slices.Equal(got, want) {
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t.Errorf("got %v; want %v", got, want)
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}
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// domains are explicitly downcased on set.
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a.UpdateDomains([]string{"UP.EXAMPLE.COM"})
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if got, want := xmaps.Keys(a.domains), []string{"up.example.com"}; !slices.Equal(got, want) {
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t.Errorf("got %v; want %v", got, want)
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}
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}
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func TestObserveDNSResponse(t *testing.T) {
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rc := &routeCollector{}
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a := NewEmbeddedAppConnector(t.Logf, rc)
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// a has no domains configured, so it should not advertise any routes
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a.ObserveDNSResponse(dnsResponse("example.com.", "192.0.0.8"))
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if got, want := rc.routes, ([]netip.Prefix)(nil); !slices.Equal(got, want) {
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t.Errorf("got %v; want %v", got, want)
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}
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wantRoutes := []netip.Prefix{netip.MustParsePrefix("192.0.0.8/32")}
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a.UpdateDomains([]string{"example.com"})
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a.ObserveDNSResponse(dnsResponse("example.com.", "192.0.0.8"))
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if got, want := rc.routes, wantRoutes; !slices.Equal(got, want) {
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t.Errorf("got %v; want %v", got, want)
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}
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wantRoutes = append(wantRoutes, netip.MustParsePrefix("2001:db8::1/128"))
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a.ObserveDNSResponse(dnsResponse("example.com.", "2001:db8::1"))
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if got, want := rc.routes, wantRoutes; !slices.Equal(got, want) {
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t.Errorf("got %v; want %v", got, want)
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}
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// don't re-advertise routes that have already been advertised
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a.ObserveDNSResponse(dnsResponse("example.com.", "2001:db8::1"))
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if !slices.Equal(rc.routes, wantRoutes) {
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t.Errorf("got %v; want %v", rc.routes, wantRoutes)
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}
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}
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// dnsResponse is a test helper that creates a DNS response buffer for the given domain and address
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func dnsResponse(domain, address string) []byte {
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addr := netip.MustParseAddr(address)
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b := dnsmessage.NewBuilder(nil, dnsmessage.Header{})
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b.EnableCompression()
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b.StartAnswers()
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switch addr.BitLen() {
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case 32:
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b.AResource(
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dnsmessage.ResourceHeader{
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Name: dnsmessage.MustNewName(domain),
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Type: dnsmessage.TypeA,
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Class: dnsmessage.ClassINET,
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TTL: 0,
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},
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dnsmessage.AResource{
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A: addr.As4(),
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},
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)
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case 128:
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b.AAAAResource(
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dnsmessage.ResourceHeader{
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Name: dnsmessage.MustNewName(domain),
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Type: dnsmessage.TypeAAAA,
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Class: dnsmessage.ClassINET,
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TTL: 0,
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},
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dnsmessage.AAAAResource{
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AAAA: addr.As16(),
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},
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)
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default:
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panic("invalid address length")
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}
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return must.Get(b.Finish())
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}
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// routeCollector is a test helper that collects the list of routes advertised
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type routeCollector struct {
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routes []netip.Prefix
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}
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// routeCollector implements RouteAdvertiser
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var _ RouteAdvertiser = (*routeCollector)(nil)
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func (rc *routeCollector) AdvertiseRoute(pfx netip.Prefix) error {
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rc.routes = append(rc.routes, pfx)
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return nil
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}
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@ -216,11 +216,13 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
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gvisor.dev/gvisor/pkg/tcpip/transport/udp from tailscale.com/net/tstun+
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gvisor.dev/gvisor/pkg/waiter from gvisor.dev/gvisor/pkg/context+
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inet.af/peercred from tailscale.com/ipn/ipnauth
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inet.af/tcpproxy from tailscale.com/appc
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W 💣 inet.af/wf from tailscale.com/wf
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nhooyr.io/websocket from tailscale.com/derp/derphttp+
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nhooyr.io/websocket/internal/errd from nhooyr.io/websocket
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nhooyr.io/websocket/internal/xsync from nhooyr.io/websocket
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tailscale.com from tailscale.com/version
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tailscale.com/appc from tailscale.com/ipn/ipnlocal
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tailscale.com/atomicfile from tailscale.com/ipn+
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LD tailscale.com/chirp from tailscale.com/cmd/tailscaled
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tailscale.com/client/tailscale from tailscale.com/derp+
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@ -269,7 +271,7 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
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tailscale.com/net/dns/publicdns from tailscale.com/net/dns/resolver+
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tailscale.com/net/dns/recursive from tailscale.com/net/dnsfallback
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tailscale.com/net/dns/resolvconffile from tailscale.com/net/dns+
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tailscale.com/net/dns/resolver from tailscale.com/ipn/ipnlocal+
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tailscale.com/net/dns/resolver from tailscale.com/net/dns
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tailscale.com/net/dnscache from tailscale.com/control/controlclient+
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tailscale.com/net/dnsfallback from tailscale.com/control/controlclient+
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tailscale.com/net/flowtrack from tailscale.com/net/packet+
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@ -319,6 +321,7 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
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tailscale.com/tstime/mono from tailscale.com/net/tstun+
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tailscale.com/tstime/rate from tailscale.com/wgengine/filter+
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tailscale.com/tsweb/varz from tailscale.com/cmd/tailscaled
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tailscale.com/types/appctype from tailscale.com/appc
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tailscale.com/types/dnstype from tailscale.com/ipn/ipnlocal+
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tailscale.com/types/empty from tailscale.com/ipn+
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tailscale.com/types/flagtype from tailscale.com/cmd/tailscaled
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@ -32,6 +32,7 @@
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"go4.org/netipx"
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xmaps "golang.org/x/exp/maps"
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"gvisor.dev/gvisor/pkg/tcpip"
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"tailscale.com/appc"
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"tailscale.com/client/tailscale/apitype"
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"tailscale.com/control/controlclient"
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"tailscale.com/control/controlknobs"
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@ -203,9 +204,10 @@ type LocalBackend struct {
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conf *conffile.Config // latest parsed config, or nil if not in declarative mode
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pm *profileManager // mu guards access
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filterHash deephash.Sum
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httpTestClient *http.Client // for controlclient. nil by default, used by tests.
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ccGen clientGen // function for producing controlclient; lazily populated
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sshServer SSHServer // or nil, initialized lazily.
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httpTestClient *http.Client // for controlclient. nil by default, used by tests.
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ccGen clientGen // function for producing controlclient; lazily populated
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sshServer SSHServer // or nil, initialized lazily.
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appConnector *appc.EmbeddedAppConnector // or nil, initialized when configured.
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webClient webClient
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notify func(ipn.Notify)
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cc controlclient.Client
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@ -2995,6 +2997,9 @@ func (b *LocalBackend) setPrefsLockedOnEntry(caller string, newp *ipn.Prefs) ipn
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oldHi := b.hostinfo
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newHi := oldHi.Clone()
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if newHi == nil {
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newHi = new(tailcfg.Hostinfo)
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}
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b.applyPrefsToHostinfoLocked(newHi, newp.View())
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b.hostinfo = newHi
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hostInfoChanged := !oldHi.Equal(newHi)
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@ -3240,6 +3245,10 @@ func (b *LocalBackend) authReconfig() {
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disableSubnetsIfPAC := hasCapability(nm, tailcfg.NodeAttrDisableSubnetsIfPAC)
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dohURL, dohURLOK := exitNodeCanProxyDNS(nm, b.peers, prefs.ExitNodeID())
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dcfg := dnsConfigForNetmap(nm, b.peers, prefs, b.logf, version.OS())
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// If the current node is an app connector, ensure the app connector machine is started
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if prefs.AppConnector().Advertise && b.appConnector == nil {
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b.appConnector = appc.NewEmbeddedAppConnector(b.logf, b)
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}
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b.mu.Unlock()
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if blocked {
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@ -4812,6 +4821,14 @@ func (b *LocalBackend) OfferingExitNode() bool {
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return def4 && def6
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}
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// OfferingAppConnector reports whether b is currently offering app
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// connector services.
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func (b *LocalBackend) OfferingAppConnector() bool {
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b.mu.Lock()
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defer b.mu.Unlock()
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return b.appConnector != nil
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}
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// allowExitNodeDNSProxyToServeName reports whether the Exit Node DNS
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// proxy is allowed to serve responses for the provided DNS name.
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func (b *LocalBackend) allowExitNodeDNSProxyToServeName(name string) bool {
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@ -5398,6 +5415,39 @@ func (b *LocalBackend) DebugBreakDERPConns() error {
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return b.magicConn().DebugBreakDERPConns()
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}
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// ObserveDNSResponse passes a DNS response from the PeerAPI DNS server to the
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// App Connector to enable route discovery.
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func (b *LocalBackend) ObserveDNSResponse(res []byte) {
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var appConnector *appc.EmbeddedAppConnector
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b.mu.Lock()
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if b.appConnector == nil {
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b.mu.Unlock()
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return
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}
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appConnector = b.appConnector
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b.mu.Unlock()
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appConnector.ObserveDNSResponse(res)
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}
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// AdvertiseRoute implements the appc.RouteAdvertiser interface. It sets a new
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// route advertisement if one is not already present in the existing routes.
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func (b *LocalBackend) AdvertiseRoute(ipp netip.Prefix) error {
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currentRoutes := b.Prefs().AdvertiseRoutes()
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// TODO(raggi): check if the new route is a subset of an existing route.
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if currentRoutes.ContainsFunc(func(r netip.Prefix) bool { return r == ipp }) {
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return nil
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}
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routes := append(currentRoutes.AsSlice(), ipp)
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_, err := b.EditPrefs(&ipn.MaskedPrefs{
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Prefs: ipn.Prefs{
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AdvertiseRoutes: routes,
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},
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AdvertiseRoutesSet: true,
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})
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return err
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}
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// mayDeref dereferences p if non-nil, otherwise it returns the zero value.
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func mayDeref[T any](p *T) (v T) {
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if p == nil {
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|
@ -10,10 +10,13 @@
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"net/http"
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"net/netip"
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"reflect"
|
||||
"slices"
|
||||
"testing"
|
||||
"time"
|
||||
|
||||
"go4.org/netipx"
|
||||
"golang.org/x/net/dns/dnsmessage"
|
||||
"tailscale.com/appc"
|
||||
"tailscale.com/control/controlclient"
|
||||
"tailscale.com/ipn"
|
||||
"tailscale.com/ipn/store/mem"
|
||||
@ -30,6 +33,7 @@
|
||||
"tailscale.com/types/ptr"
|
||||
"tailscale.com/util/dnsname"
|
||||
"tailscale.com/util/mak"
|
||||
"tailscale.com/util/must"
|
||||
"tailscale.com/util/set"
|
||||
"tailscale.com/wgengine"
|
||||
"tailscale.com/wgengine/filter"
|
||||
@ -1142,6 +1146,47 @@ type tc struct {
|
||||
}
|
||||
}
|
||||
|
||||
func TestOfferingAppConnector(t *testing.T) {
|
||||
b := newTestBackend(t)
|
||||
if b.OfferingAppConnector() {
|
||||
t.Fatal("unexpected offering app connector")
|
||||
}
|
||||
b.appConnector = appc.NewEmbeddedAppConnector(t.Logf, nil)
|
||||
if !b.OfferingAppConnector() {
|
||||
t.Fatal("unexpected not offering app connector")
|
||||
}
|
||||
}
|
||||
|
||||
func TestRouteAdvertiser(t *testing.T) {
|
||||
b := newTestBackend(t)
|
||||
testPrefix := netip.MustParsePrefix("192.0.0.8/32")
|
||||
|
||||
ra := appc.RouteAdvertiser(b)
|
||||
must.Do(ra.AdvertiseRoute(testPrefix))
|
||||
|
||||
routes := b.Prefs().AdvertiseRoutes()
|
||||
if routes.Len() != 1 || routes.At(0) != testPrefix {
|
||||
t.Fatalf("got routes %v, want %v", routes, []netip.Prefix{testPrefix})
|
||||
}
|
||||
}
|
||||
|
||||
func TestObserveDNSResponse(t *testing.T) {
|
||||
b := newTestBackend(t)
|
||||
|
||||
// ensure no error when no app connector is configured
|
||||
b.ObserveDNSResponse(dnsResponse("example.com.", "192.0.0.8"))
|
||||
|
||||
rc := &routeCollector{}
|
||||
b.appConnector = appc.NewEmbeddedAppConnector(t.Logf, rc)
|
||||
b.appConnector.UpdateDomains([]string{"example.com"})
|
||||
|
||||
b.ObserveDNSResponse(dnsResponse("example.com.", "192.0.0.8"))
|
||||
wantRoutes := []netip.Prefix{netip.MustParsePrefix("192.0.0.8/32")}
|
||||
if !slices.Equal(rc.routes, wantRoutes) {
|
||||
t.Fatalf("got routes %v, want %v", rc.routes, wantRoutes)
|
||||
}
|
||||
}
|
||||
|
||||
func resolversEqual(t *testing.T, a, b []*dnstype.Resolver) bool {
|
||||
if a == nil && b == nil {
|
||||
return true
|
||||
@ -1176,3 +1221,50 @@ func routesEqual(t *testing.T, a, b map[dnsname.FQDN][]*dnstype.Resolver) bool {
|
||||
}
|
||||
return true
|
||||
}
|
||||
|
||||
// dnsResponse is a test helper that creates a DNS response buffer for the given domain and address
|
||||
func dnsResponse(domain, address string) []byte {
|
||||
addr := netip.MustParseAddr(address)
|
||||
b := dnsmessage.NewBuilder(nil, dnsmessage.Header{})
|
||||
b.EnableCompression()
|
||||
b.StartAnswers()
|
||||
switch addr.BitLen() {
|
||||
case 32:
|
||||
b.AResource(
|
||||
dnsmessage.ResourceHeader{
|
||||
Name: dnsmessage.MustNewName(domain),
|
||||
Type: dnsmessage.TypeA,
|
||||
Class: dnsmessage.ClassINET,
|
||||
TTL: 0,
|
||||
},
|
||||
dnsmessage.AResource{
|
||||
A: addr.As4(),
|
||||
},
|
||||
)
|
||||
case 128:
|
||||
b.AAAAResource(
|
||||
dnsmessage.ResourceHeader{
|
||||
Name: dnsmessage.MustNewName(domain),
|
||||
Type: dnsmessage.TypeAAAA,
|
||||
Class: dnsmessage.ClassINET,
|
||||
TTL: 0,
|
||||
},
|
||||
dnsmessage.AAAAResource{
|
||||
AAAA: addr.As16(),
|
||||
},
|
||||
)
|
||||
default:
|
||||
panic("invalid address length")
|
||||
}
|
||||
return must.Get(b.Finish())
|
||||
}
|
||||
|
||||
// routeCollector is a test helper that collects the list of routes advertised
|
||||
type routeCollector struct {
|
||||
routes []netip.Prefix
|
||||
}
|
||||
|
||||
func (rc *routeCollector) AdvertiseRoute(pfx netip.Prefix) error {
|
||||
rc.routes = append(rc.routes, pfx)
|
||||
return nil
|
||||
}
|
||||
|
@ -32,7 +32,6 @@
|
||||
"tailscale.com/health"
|
||||
"tailscale.com/hostinfo"
|
||||
"tailscale.com/ipn"
|
||||
"tailscale.com/net/dns/resolver"
|
||||
"tailscale.com/net/interfaces"
|
||||
"tailscale.com/net/netaddr"
|
||||
"tailscale.com/net/netutil"
|
||||
@ -51,9 +50,14 @@
|
||||
// ("cleartext" HTTP/2) support to the peerAPI.
|
||||
var addH2C func(*http.Server)
|
||||
|
||||
// peerDNSQueryHandler is implemented by tsdns.Resolver.
|
||||
type peerDNSQueryHandler interface {
|
||||
HandlePeerDNSQuery(context.Context, []byte, netip.AddrPort, func(name string) bool) (res []byte, err error)
|
||||
}
|
||||
|
||||
type peerAPIServer struct {
|
||||
b *LocalBackend
|
||||
resolver *resolver.Resolver
|
||||
resolver peerDNSQueryHandler
|
||||
|
||||
taildrop *taildrop.Manager
|
||||
}
|
||||
@ -861,9 +865,9 @@ func (h *peerAPIHandler) replyToDNSQueries() bool {
|
||||
return true
|
||||
}
|
||||
b := h.ps.b
|
||||
if !b.OfferingExitNode() {
|
||||
// If we're not an exit node, there's no point to
|
||||
// being a DNS server for somebody.
|
||||
if !b.OfferingExitNode() && !b.OfferingAppConnector() {
|
||||
// If we're not an exit node or app connector, there's
|
||||
// no point to being a DNS server for somebody.
|
||||
return false
|
||||
}
|
||||
if !h.remoteAddr.IsValid() {
|
||||
@ -927,7 +931,7 @@ func (h *peerAPIHandler) handleDNSQuery(w http.ResponseWriter, r *http.Request)
|
||||
|
||||
ctx, cancel := context.WithTimeout(r.Context(), arbitraryTimeout)
|
||||
defer cancel()
|
||||
res, err := h.ps.resolver.HandleExitNodeDNSQuery(ctx, q, h.remoteAddr, h.ps.b.allowExitNodeDNSProxyToServeName)
|
||||
res, err := h.ps.resolver.HandlePeerDNSQuery(ctx, q, h.remoteAddr, h.ps.b.allowExitNodeDNSProxyToServeName)
|
||||
if err != nil {
|
||||
h.logf("handleDNS fwd error: %v", err)
|
||||
if err := ctx.Err(); err != nil {
|
||||
@ -937,6 +941,13 @@ func (h *peerAPIHandler) handleDNSQuery(w http.ResponseWriter, r *http.Request)
|
||||
}
|
||||
return
|
||||
}
|
||||
// TODO(raggi): consider pushing the integration down into the resolver
|
||||
// instead to avoid re-parsing the DNS response for improved performance in
|
||||
// the future.
|
||||
if h.ps.b.OfferingAppConnector() {
|
||||
h.ps.b.ObserveDNSResponse(res)
|
||||
}
|
||||
|
||||
if pretty {
|
||||
// Non-standard response for interactive debugging.
|
||||
w.Header().Set("Content-Type", "application/json")
|
||||
|
@ -5,6 +5,7 @@
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"context"
|
||||
"fmt"
|
||||
"io"
|
||||
"io/fs"
|
||||
@ -14,11 +15,14 @@
|
||||
"net/netip"
|
||||
"os"
|
||||
"path/filepath"
|
||||
"slices"
|
||||
"strings"
|
||||
"testing"
|
||||
|
||||
"github.com/google/go-cmp/cmp"
|
||||
"go4.org/netipx"
|
||||
"golang.org/x/net/dns/dnsmessage"
|
||||
"tailscale.com/appc"
|
||||
"tailscale.com/client/tailscale/apitype"
|
||||
"tailscale.com/ipn"
|
||||
"tailscale.com/ipn/store/mem"
|
||||
@ -680,3 +684,63 @@ func TestPeerAPIReplyToDNSQueries(t *testing.T) {
|
||||
t.Errorf("unexpectedly IPv6 deny; wanted to be a DNS server")
|
||||
}
|
||||
}
|
||||
|
||||
func TestPeerAPIReplyToDNSQueriesAreObserved(t *testing.T) {
|
||||
var h peerAPIHandler
|
||||
h.remoteAddr = netip.MustParseAddrPort("100.150.151.152:12345")
|
||||
|
||||
rc := &routeCollector{}
|
||||
eng, _ := wgengine.NewFakeUserspaceEngine(logger.Discard, 0)
|
||||
pm := must.Get(newProfileManager(new(mem.Store), t.Logf))
|
||||
h.ps = &peerAPIServer{
|
||||
b: &LocalBackend{
|
||||
e: eng,
|
||||
pm: pm,
|
||||
store: pm.Store(),
|
||||
appConnector: appc.NewEmbeddedAppConnector(t.Logf, rc),
|
||||
},
|
||||
}
|
||||
h.ps.b.appConnector.UpdateDomains([]string{"example.com"})
|
||||
|
||||
h.ps.resolver = &fakeResolver{}
|
||||
f := filter.NewAllowAllForTest(logger.Discard)
|
||||
h.ps.b.setFilter(f)
|
||||
|
||||
if !h.ps.b.OfferingAppConnector() {
|
||||
t.Fatal("expecting to be offering app connector")
|
||||
}
|
||||
if !h.replyToDNSQueries() {
|
||||
t.Errorf("unexpectedly deny; wanted to be a DNS server")
|
||||
}
|
||||
|
||||
w := httptest.NewRecorder()
|
||||
h.handleDNSQuery(w, httptest.NewRequest("GET", "/dns-query?q=true&t=example.com.", nil))
|
||||
if w.Code != http.StatusOK {
|
||||
t.Errorf("unexpected status code: %v", w.Code)
|
||||
}
|
||||
|
||||
wantRoutes := []netip.Prefix{netip.MustParsePrefix("192.0.0.8/32")}
|
||||
if !slices.Equal(rc.routes, wantRoutes) {
|
||||
t.Errorf("got %v; want %v", rc.routes, wantRoutes)
|
||||
}
|
||||
}
|
||||
|
||||
type fakeResolver struct{}
|
||||
|
||||
func (f *fakeResolver) HandlePeerDNSQuery(ctx context.Context, q []byte, from netip.AddrPort, allowName func(name string) bool) (res []byte, err error) {
|
||||
b := dnsmessage.NewBuilder(nil, dnsmessage.Header{})
|
||||
b.EnableCompression()
|
||||
b.StartAnswers()
|
||||
b.AResource(
|
||||
dnsmessage.ResourceHeader{
|
||||
Name: dnsmessage.MustNewName("example.com."),
|
||||
Type: dnsmessage.TypeA,
|
||||
Class: dnsmessage.ClassINET,
|
||||
TTL: 0,
|
||||
},
|
||||
dnsmessage.AResource{
|
||||
A: [4]byte{192, 0, 0, 8},
|
||||
},
|
||||
)
|
||||
return b.Finish()
|
||||
}
|
||||
|
@ -314,9 +314,9 @@ func parseExitNodeQuery(q []byte) *response {
|
||||
return p.response()
|
||||
}
|
||||
|
||||
// HandleExitNodeDNSQuery handles a DNS query that arrived from a peer
|
||||
// via the peerapi's DoH server. This is only used when the local
|
||||
// node is being an exit node.
|
||||
// HandlePeerDNSQuery handles a DNS query that arrived from a peer
|
||||
// via the peerapi's DoH server. This is used when the local
|
||||
// node is being an exit node or an app connector.
|
||||
//
|
||||
// The provided allowName callback is whether a DNS query for a name
|
||||
// (as found by parsing q) is allowed.
|
||||
@ -325,7 +325,7 @@ func parseExitNodeQuery(q []byte) *response {
|
||||
// still result in a response DNS packet (saying there's a failure)
|
||||
// and a nil error.
|
||||
// TODO: figure out if we even need an error result.
|
||||
func (r *Resolver) HandleExitNodeDNSQuery(ctx context.Context, q []byte, from netip.AddrPort, allowName func(name string) bool) (res []byte, err error) {
|
||||
func (r *Resolver) HandlePeerDNSQuery(ctx context.Context, q []byte, from netip.AddrPort, allowName func(name string) bool) (res []byte, err error) {
|
||||
metricDNSExitProxyQuery.Add(1)
|
||||
ch := make(chan packet, 1)
|
||||
|
||||
|
Loading…
Reference in New Issue
Block a user