appc,feature/conn25: conn25: send address assignments to connector

After we intercept a DNS response and assign magic and transit addresses we must communicate the assignment to our connector so that it can direct traffic when it arrives. Use the recently added peerapi endpoint to send the addresses. Updates tailscale/corp#34258 Signed-off-by: Fran Bull <fran@tailscale.com>
2026-02-27 14:31:43 -08:00
parent 6a19995f13
commit a4614d7d17
10 changed files with 486 additions and 37 deletions
@@ -8,6 +8,8 @@ import (
 	"reflect"
 	"testing"

+	"github.com/google/go-cmp/cmp"
+	"tailscale.com/ipn/ipnext"
 	"tailscale.com/tailcfg"
 	"tailscale.com/types/appctype"
 	"tailscale.com/types/opt"
@@ -131,3 +133,157 @@ func TestPickSplitDNSPeers(t *testing.T) {
 		})
 	}
 }
+
+type testNodeBackend struct {
+	ipnext.NodeBackend
+	peers []tailcfg.NodeView
+}
+
+func (nb *testNodeBackend) AppendMatchingPeers(base []tailcfg.NodeView, pred func(tailcfg.NodeView) bool) []tailcfg.NodeView {
+	for _, p := range nb.peers {
+		if pred(p) {
+			base = append(base, p)
+		}
+	}
+	return base
+}
+
+func (nb *testNodeBackend) PeerHasPeerAPI(p tailcfg.NodeView) bool {
+	return true
+}
+
+func TestPickConnector(t *testing.T) {
+	exampleApp := appctype.Conn25Attr{
+		Name:       "example",
+		Connectors: []string{"tag:example"},
+		Domains:    []string{"example.com"},
+	}
+
+	nvWithConnectorSet := func(id tailcfg.NodeID, isConnector bool, tags ...string) tailcfg.NodeView {
+		return (&tailcfg.Node{
+			ID:       id,
+			Tags:     tags,
+			Hostinfo: (&tailcfg.Hostinfo{AppConnector: opt.NewBool(isConnector)}).View(),
+		}).View()
+	}
+
+	nv := func(id tailcfg.NodeID, tags ...string) tailcfg.NodeView {
+		return nvWithConnectorSet(id, true, tags...)
+	}
+
+	for _, tt := range []struct {
+		name       string
+		candidates []tailcfg.NodeView
+		app        appctype.Conn25Attr
+		want       []tailcfg.NodeView
+	}{
+		{
+			name:       "empty-everything",
+			candidates: []tailcfg.NodeView{},
+			app:        appctype.Conn25Attr{},
+			want:       nil,
+		},
+		{
+			name:       "empty-candidates",
+			candidates: []tailcfg.NodeView{},
+			app:        exampleApp,
+			want:       nil,
+		},
+		{
+			name:       "empty-app",
+			candidates: []tailcfg.NodeView{nv(1, "tag:example")},
+			app:        appctype.Conn25Attr{},
+			want:       nil,
+		},
+		{
+			name:       "one-matches",
+			candidates: []tailcfg.NodeView{nv(1, "tag:example")},
+			app:        exampleApp,
+			want:       []tailcfg.NodeView{nv(1, "tag:example")},
+		},
+		{
+			name: "invalid-candidate",
+			candidates: []tailcfg.NodeView{
+				{},
+				nv(1, "tag:example"),
+			},
+			app: exampleApp,
+			want: []tailcfg.NodeView{
+				nv(1, "tag:example"),
+			},
+		},
+		{
+			name: "no-host-info",
+			candidates: []tailcfg.NodeView{
+				(&tailcfg.Node{
+					ID:   1,
+					Tags: []string{"tag:example"},
+				}).View(),
+				nv(2, "tag:example"),
+			},
+			app:  exampleApp,
+			want: []tailcfg.NodeView{nv(2, "tag:example")},
+		},
+		{
+			name:       "not-a-connector",
+			candidates: []tailcfg.NodeView{nvWithConnectorSet(1, false, "tag:example.com"), nv(2, "tag:example")},
+			app:        exampleApp,
+			want:       []tailcfg.NodeView{nv(2, "tag:example")},
+		},
+		{
+			name:       "without-matches",
+			candidates: []tailcfg.NodeView{nv(1, "tag:woo"), nv(2, "tag:example")},
+			app:        exampleApp,
+			want:       []tailcfg.NodeView{nv(2, "tag:example")},
+		},
+		{
+			name:       "multi-tags",
+			candidates: []tailcfg.NodeView{nv(1, "tag:woo", "tag:hoo"), nv(2, "tag:woo", "tag:example")},
+			app:        exampleApp,
+			want:       []tailcfg.NodeView{nv(2, "tag:woo", "tag:example")},
+		},
+		{
+			name:       "multi-matches",
+			candidates: []tailcfg.NodeView{nv(1, "tag:woo", "tag:hoo"), nv(2, "tag:woo", "tag:example"), nv(3, "tag:example1", "tag:example")},
+			app: appctype.Conn25Attr{
+				Name:       "example2",
+				Connectors: []string{"tag:example1", "tag:example"},
+				Domains:    []string{"example.com"},
+			},
+			want: []tailcfg.NodeView{nv(2, "tag:woo", "tag:example"), nv(3, "tag:example1", "tag:example")},
+		},
+		{
+			name: "bit-of-everything",
+			candidates: []tailcfg.NodeView{
+				nv(3, "tag:woo", "tag:hoo"),
+				{},
+				nv(2, "tag:woo", "tag:example"),
+				nvWithConnectorSet(4, false, "tag:example"),
+				nv(1, "tag:example1", "tag:example"),
+				nv(7, "tag:example1", "tag:example"),
+				nvWithConnectorSet(5, false),
+				nv(6),
+				nvWithConnectorSet(8, false, "tag:example"),
+				nvWithConnectorSet(9, false),
+				nvWithConnectorSet(10, false),
+			},
+			app: appctype.Conn25Attr{
+				Name:       "example2",
+				Connectors: []string{"tag:example1", "tag:example", "tag:example2"},
+				Domains:    []string{"example.com"},
+			},
+			want: []tailcfg.NodeView{
+				nv(1, "tag:example1", "tag:example"),
+				nv(2, "tag:woo", "tag:example"),
+				nv(7, "tag:example1", "tag:example"),
+			},
+		},
+	} {
+		t.Run(tt.name, func(t *testing.T) {
+			got := PickConnector(&testNodeBackend{peers: tt.candidates}, tt.app)
+			if diff := cmp.Diff(tt.want, got); diff != "" {
+				t.Fatalf("PickConnectors (-want, +got):\n%s", diff)
+			}
+		})
+	}
+}