Files
weave/npc/rule.go
T

89 lines
2.3 KiB
Go

package npc
import (
"fmt"
"strings"
"k8s.io/apimachinery/pkg/types"
"github.com/weaveworks/weave/common"
"github.com/weaveworks/weave/npc/iptables"
)
type ruleSpec struct {
key string
args []string
}
func newRuleSpec(proto *string, srcHost *selectorSpec, dstHost *selectorSpec, dstPort *string) *ruleSpec {
args := []string{}
if proto != nil {
args = append(args, "-p", *proto)
}
srcComment := "anywhere"
if srcHost != nil {
args = append(args, "-m", "set", "--match-set", string(srcHost.ipsetName), "src")
if srcHost.nsName != "" {
srcComment = fmt.Sprintf("pods: namespace: %s, selector: %s", srcHost.nsName, srcHost.key)
} else {
srcComment = fmt.Sprintf("namespaces: selector: %s", srcHost.key)
}
}
dstComment := "anywhere"
if dstHost != nil {
args = append(args, "-m", "set", "--match-set", string(dstHost.ipsetName), "dst")
dstComment = fmt.Sprintf("pods: namespace: %s, selector: %s", dstHost.nsName, dstHost.key)
}
if dstPort != nil {
args = append(args, "--dport", *dstPort)
}
args = append(args, "-j", "ACCEPT")
args = append(args, "-m", "comment", "--comment", fmt.Sprintf("%s -> %s", srcComment, dstComment))
key := strings.Join(args, " ")
return &ruleSpec{key, args}
}
type ruleSet struct {
ipt iptables.Interface
users map[string]map[types.UID]struct{}
}
func newRuleSet(ipt iptables.Interface) *ruleSet {
return &ruleSet{ipt, make(map[string]map[types.UID]struct{})}
}
func (rs *ruleSet) deprovision(user types.UID, current, desired map[string]*ruleSpec) error {
for key, spec := range current {
if _, found := desired[key]; !found {
delete(rs.users[key], user)
if len(rs.users[key]) == 0 {
common.Log.Infof("deleting rule: %v", spec.args)
if err := rs.ipt.Delete(TableFilter, IngressChain, spec.args...); err != nil {
return err
}
delete(rs.users, key)
}
}
}
return nil
}
func (rs *ruleSet) provision(user types.UID, current, desired map[string]*ruleSpec) error {
for key, spec := range desired {
if _, found := current[key]; !found {
if _, found := rs.users[key]; !found {
common.Log.Infof("adding rule: %v", spec.args)
if err := rs.ipt.Append(TableFilter, IngressChain, spec.args...); err != nil {
return err
}
rs.users[key] = make(map[types.UID]struct{})
}
rs.users[key][user] = struct{}{}
}
}
return nil
}