support ipblock in npc

NOTE(brb): This commit is cherry-picked from the kitt1987/ipblock
branch.

npc/ipblock.go

@@ -0,0 +1,120 @@
+package npc
+
+import (
+	"github.com/weaveworks/weave/common"
+	"github.com/weaveworks/weave/npc/ipset"
+	networkingv1 "k8s.io/api/networking/v1"
+	"k8s.io/apimachinery/pkg/types"
+	"net"
+	"sort"
+	"strings"
+)
+
+type ipBlock struct {
+	ipsetName ipset.Name // generated ipset name
+	spec      *networkingv1.IPBlock
+}
+
+func newIPBlock(ipb *networkingv1.IPBlock, ns string) (b *ipBlock, err error) {
+	if _, _, err = net.ParseCIDR(ipb.CIDR); err != nil {
+		return
+	}
+
+	for _, ex := range ipb.Except {
+		if _, _, err = net.ParseCIDR(ex); err != nil {
+			return
+		}
+	}
+
+	b = &ipBlock{spec: ipb}
+
+	if len(ipb.Except) > 0 {
+		sortedExcept := ipb.Except
+		sort.Strings(sortedExcept)
+		b.ipsetName = ipset.Name(IpsetNamePrefix + shortName("except:"+strings.Join(sortedExcept, "")))
+	}
+
+	return
+}
+
+//func (ipb ipBlock) GetRuleSpec() (spec *ruleSpec) {
+//	spec = &ruleSpec{
+//		chain: IngressIPBlockChain,
+//	}
+//
+//	if len(ipb.spec.Except) == 0 {
+//		spec.args = append(spec.args, "-s", ipb.spec.CIDR)
+//		spec.comment = fmt.Sprintf("cidr: %s", ipb.spec.CIDR)
+//	} else {
+//		spec.args = append(spec.args, "-s", ipb.spec.CIDR, "-m", "set", "!", "--match-set",
+//			string(ipb.ipsetName), "src")
+//		spec.comment = fmt.Sprintf("cidr: %s except [%s]", ipb.spec.CIDR,
+//			strings.Join(ipb.spec.Except, `,`))
+//	}
+//	return
+//}
+
+type ipBlockSet struct {
+	ips   ipset.Interface
+	users map[string]int
+}
+
+func newIPBlockSet(ips ipset.Interface) *ipBlockSet {
+	return &ipBlockSet{
+		ips:   ips,
+		users: make(map[string]int),
+	}
+}
+
+func (s *ipBlockSet) deprovision(uid types.UID, current *ipBlock) (err error) {
+	if current == nil || len(current.ipsetName) == 0 {
+		return
+	}
+
+	key := string(current.ipsetName)
+	if _, found := s.users[key]; !found {
+		return
+	}
+
+	s.users[key]--
+	if s.users[key] == 0 {
+		if err = s.ips.Destroy(current.ipsetName); err != nil {
+			return
+		}
+
+		delete(s.users, key)
+	}
+
+	return
+}
+
+func (s *ipBlockSet) provision(uid types.UID, desired *ipBlock) (err error) {
+	if desired == nil || len(desired.ipsetName) == 0 {
+		return
+	}
+
+	key := string(desired.ipsetName)
+	if _, found := s.users[key]; found {
+		common.Log.Debug()
+		s.users[key]++
+		return
+	}
+
+	err = s.ips.Create(desired.ipsetName, ipset.HashNet)
+	if err != nil {
+		return
+	}
+
+	comment := `excepted from ` + desired.spec.CIDR
+	for _, excepted := range desired.spec.Except {
+		if err = s.ips.AddEntry(uid, desired.ipsetName, excepted, comment); err != nil {
+			if details := s.ips.Destroy(desired.ipsetName); details != nil {
+				common.Log.Warn("can't destroy ipset ", desired.ipsetName, ":", details)
+			}
+			return
+		}
+	}
+
+	s.users[key] = 1
+	return
+}