all: deprecate Node.Capabilities (more), remove PeerChange.Capabilities [capver 89]

First we had Capabilities []string. Then
https://tailscale.com/blog/acl-grants (#4217) brought CapMap, a
superset of Capabilities. Except we never really finished the
transition inside the codebase to go all-in on CapMap. This does so.

Notably, this coverts Capabilities on the wire early to CapMap
internally so the code can only deal in CapMap, even against an old
control server.

In the process, this removes PeerChange.Capabilities support, which no
known control plane sent anyway. They can and should use
PeerChange.CapMap instead.

Updates #11508
Updates #4217

Change-Id: I872074e226b873f9a578d9603897b831d50b25d9
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>

1 files changed, 2 insertions, 6 deletions

diff --git a/control/controlknobs/controlknobs.go b/control/controlknobs/controlknobs.go
index 6a36c9261..6e3a62967 100644
--- a/control/controlknobs/controlknobs.go
+++ b/control/controlknobs/controlknobs.go
@@ -6,7 +6,6 @@
 package controlknobs
 
 import (
-	"slices"
 	"sync/atomic"
 
 	"tailscale.com/syncs"
@@ -77,14 +76,11 @@ type Knobs struct {
 
 // UpdateFromNodeAttributes updates k (if non-nil) based on the provided self
 // node attributes (Node.Capabilities).
-func (k *Knobs) UpdateFromNodeAttributes(selfNodeAttrs []tailcfg.NodeCapability, capMap tailcfg.NodeCapMap) {
+func (k *Knobs) UpdateFromNodeAttributes(capMap tailcfg.NodeCapMap) {
 	if k == nil {
 		return
 	}
-	has := func(attr tailcfg.NodeCapability) bool {
-		_, ok := capMap[attr]
-		return ok || slices.Contains(selfNodeAttrs, attr)
-	}
+	has := capMap.Contains
 	var (
 		keepFullWG                    = has(tailcfg.NodeAttrDebugDisableWGTrim)
 		disableDRPO                   = has(tailcfg.NodeAttrDebugDisableDRPO)