[client] Unify peer and route ACL filtering with multi-source rules (#6322)

* Unify peer and route ACL filtering with multi-source peer rules

* Remove partial userspace firewall mode and open foreign chains via a table-less allower

* Snapshot iptables rule maps before persisting state

* Scope userspace firewall wildcard source rules per address family

* Install nftables peer filter and mangle rules in a single transaction

* Share the iptables jump rule spec between install and cleanup

* Fix legacy ACL source wildcard and keep rollback tracking on delete failure

* Fix CI: recognize multi-value port set lookups in tests and correct PeerIP lint suppression

* Fall back to per-prefix filter rules when ipset is unavailable

* Annotate legacy PeerIP usages in ACL tests and fix import formatting

* Keep firewall rule bookkeeping in step with the kernel on replace and teardown

* Release the routing reference when the route manager shuts down

* Keep set references and rule tracking consistent when a routing rule fails

client/firewall/nftables/ipsetstore_linux.go

@@ -1,85 +0,0 @@
-package nftables
-
-import (
-	"net"
-)
-
-type ipsetStore struct {
-	ipsetReference map[string]int
-	ipsets         map[string]map[string]struct{} // ipsetName -> list of ips
-}
-
-func newIpsetStore() *ipsetStore {
-	return &ipsetStore{
-		ipsetReference: make(map[string]int),
-		ipsets:         make(map[string]map[string]struct{}),
-	}
-}
-
-func (s *ipsetStore) ips(ipsetName string) (map[string]struct{}, bool) {
-	r, ok := s.ipsets[ipsetName]
-	return r, ok
-}
-
-func (s *ipsetStore) newIpset(ipsetName string) map[string]struct{} {
-	s.ipsetReference[ipsetName] = 0
-	ipList := make(map[string]struct{})
-	s.ipsets[ipsetName] = ipList
-	return ipList
-}
-
-func (s *ipsetStore) deleteIpset(ipsetName string) {
-	delete(s.ipsetReference, ipsetName)
-	delete(s.ipsets, ipsetName)
-}
-
-func (s *ipsetStore) DeleteIpFromSet(ipsetName string, ip net.IP) {
-	ipList, ok := s.ipsets[ipsetName]
-	if !ok {
-		return
-	}
-	delete(ipList, ip.String())
-}
-
-func (s *ipsetStore) AddIpToSet(ipsetName string, ip net.IP) {
-	ipList, ok := s.ipsets[ipsetName]
-	if !ok {
-		return
-	}
-	ipList[ip.String()] = struct{}{}
-}
-
-func (s *ipsetStore) IsIpInSet(ipsetName string, ip net.IP) bool {
-	ipList, ok := s.ipsets[ipsetName]
-	if !ok {
-		return false
-	}
-	_, ok = ipList[ip.String()]
-	return ok
-}
-
-func (s *ipsetStore) AddReferenceToIpset(ipsetName string) {
-	s.ipsetReference[ipsetName]++
-}
-
-func (s *ipsetStore) DeleteReferenceFromIpSet(ipsetName string) {
-	r, ok := s.ipsetReference[ipsetName]
-	if !ok {
-		return
-	}
-	if r == 0 {
-		return
-	}
-	s.ipsetReference[ipsetName]--
-}
-
-func (s *ipsetStore) HasReferenceToSet(ipsetName string) bool {
-	if _, ok := s.ipsetReference[ipsetName]; !ok {
-		return false
-	}
-	if s.ipsetReference[ipsetName] == 0 {
-		return false
-	}
-
-	return true
-}