Files
weave/server/zone.go
T
2014-10-14 17:01:13 +01:00

102 lines
2.1 KiB
Go

package weavedns
import (
"github.com/miekg/dns"
"log"
"net"
"sync"
)
type Zone interface {
AddRecord(string, string, net.IP, net.IP, *net.IPNet) error
DeleteRecord(ident string, weave_ip net.IP) error
MatchLocal(string) (net.IP, error)
}
type Record struct {
Ident string
Name string
Ip net.IP
WeaveIp net.IP
Subnet *net.IPNet
}
type ZoneDb struct {
mx sync.RWMutex
recs []Record
}
type LookupError string
func (ops LookupError) Error() string {
return "Unable to find " + string(ops)
}
type DuplicateError struct {
Name string
WeaveIp net.IP
Ident string
}
func (err DuplicateError) Error() string {
return "Duplicate " + err.Name + "," + err.WeaveIp.String() + " in container " + err.Ident
}
// Stop gap.
func (zone *ZoneDb) match(name string) (net.IP, error) {
for _, r := range zone.recs {
log.Printf("%s == %s ?", r.Name, name)
if r.Name == name {
return r.WeaveIp, nil
}
}
return nil, LookupError(name)
}
func (zone *ZoneDb) indexOfNameAddr(name string, addr net.IP) int {
for i, r := range zone.recs {
if r.Name == name && r.WeaveIp.Equal(addr) {
return i
}
}
return -1
}
func (zone *ZoneDb) indexOfIdentAddr(ident string, addr net.IP) int {
for i, r := range zone.recs {
if r.Ident == ident && r.WeaveIp.Equal(addr) {
return i
}
}
return -1
}
func (zone *ZoneDb) MatchLocal(name string) (net.IP, error) {
zone.mx.Lock()
defer zone.mx.Unlock()
return zone.match(name)
}
func (zone *ZoneDb) AddRecord(identifier string, name string, ip net.IP, weave_ip net.IP, weave_subnet *net.IPNet) error {
zone.mx.Lock()
defer zone.mx.Unlock()
fqdn := dns.Fqdn(name)
if index := zone.indexOfNameAddr(fqdn, weave_ip); index != -1 {
return DuplicateError{fqdn, weave_ip, zone.recs[index].Ident}
}
zone.recs = append(zone.recs, Record{identifier, fqdn, ip, weave_ip, weave_subnet})
return nil
}
func (zone *ZoneDb) DeleteRecord(ident string, weave_ip net.IP) error {
zone.mx.Lock()
defer zone.mx.Unlock()
if index := zone.indexOfIdentAddr(ident, weave_ip); index == -1 {
return LookupError(ident)
} else {
zone.recs = append(zone.recs[:index], zone.recs[index+1:]...)
}
return nil
}