IPN: Update ServeConfig to accept configuration for Services.

This commit updates ServeConfig to allow configuration to Services (VIPServices for now) via Serve.
The scope of this commit is only adding the Services field to ServeConfig. The field doesn't actually
allow packet flowing yet. The purpose of this commit is to unblock other work on k8s end.

Updates #22953

Signed-off-by: KevinLiang10 <[email protected]>

Author: KevinLiang10

ipn/doc.go

@@ -1,7 +1,7 @@
 // Copyright (c) Tailscale Inc & AUTHORS
 // SPDX-License-Identifier: BSD-3-Clause
 
-//go:generate go run tailscale.com/cmd/viewer -type=Prefs,ServeConfig,TCPPortHandler,HTTPHandler,WebServerConfig
+//go:generate go run tailscale.com/cmd/viewer -type=Prefs,ServeConfig,ServiceConfig,TCPPortHandler,HTTPHandler,WebServerConfig
 
 // Package ipn implements the interactions between the Tailscale cloud
 // control plane and the local network stack.

ipn/ipn_clone.go

@@ -24,6 +24,23 @@ func ServeConfigKey(profileID ProfileID) StateKey {
 	return StateKey("_serve/" + profileID)
 }
 
+// ServiceConfig contains the config information for a single service.
+// it contains a bool to indicate if the service is in Tun mode (L3 forwarding).
+// If the service is not in Tun mode, the service is configured by the L4 forwarding
+// (TCP ports) and/or the L7 forwarding (http handlers) information.
+type ServiceConfig struct {
+	// TCP are the list of TCP port numbers that tailscaled should handle for
+	// the Tailscale IP addresses. (not subnet routers, etc)
+	TCP map[uint16]*TCPPortHandler `json:",omitempty"`
+
+	// Web maps from "$SNI_NAME:$PORT" to a set of HTTP handlers
+	// keyed by mount point ("/", "/foo", etc)
+	Web map[HostPort]*WebServerConfig `json:",omitempty"`
+
+	// Tun determines if the service should be using L3 forwarding (Tun mode).
+	Tun bool `json:",omitempty"`
+}
+
 // ServeConfig is the JSON type stored in the StateStore for
 // StateKey "_serve/$PROFILE_ID" as returned by ServeConfigKey.
 type ServeConfig struct {
@@ -35,6 +52,10 @@ type ServeConfig struct {
 	// keyed by mount point ("/", "/foo", etc)
 	Web map[HostPort]*WebServerConfig `json:",omitempty"`
 
+	// Services maps from service name to a ServiceConfig. Which describes the
+	// L3, L4, and L7 forwarding information for the service.
+	Services map[string]*ServiceConfig `json:",omitempty"`
+
 	// AllowFunnel is the set of SNI:port values for which funnel
 	// traffic is allowed, from trusted ingress peers.
 	AllowFunnel map[HostPort]bool `json:",omitempty"`