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package file
import (
"fmt"
"log"
"os"
"path"
"strings"
"sync"
"github.com/miekg/coredns/middleware/file/tree"
"github.com/miekg/coredns/request"
"github.com/fsnotify/fsnotify"
"github.com/miekg/dns"
)
type Zone struct {
origin string
file string
*tree.Tree
Apex Apex
TransferTo []string
StartupOnce sync.Once
TransferFrom []string
Expired *bool
NoReload bool
reloadMu sync.RWMutex
// TODO: shutdown watcher channel
}
type Apex struct {
SOA *dns.SOA
NS []dns.RR
SIGSOA []dns.RR
SIGNS []dns.RR
}
// NewZone returns a new zone.
func NewZone(name, file string) *Zone {
z := &Zone{origin: dns.Fqdn(name), file: path.Clean(file), Tree: &tree.Tree{}, Expired: new(bool)}
*z.Expired = false
return z
}
// Copy copies a zone *without* copying the zone's content. It is not a deep copy.
func (z *Zone) Copy() *Zone {
z1 := NewZone(z.origin, z.file)
z1.TransferTo = z.TransferTo
z1.TransferFrom = z.TransferFrom
z1.Expired = z.Expired
z1.Apex = z.Apex
return z1
}
// Insert inserts r into z.
func (z *Zone) Insert(r dns.RR) error {
r.Header().Name = strings.ToLower(r.Header().Name)
switch h := r.Header().Rrtype; h {
case dns.TypeNS:
r.(*dns.NS).Ns = strings.ToLower(r.(*dns.NS).Ns)
if r.Header().Name == z.origin {
z.Apex.NS = append(z.Apex.NS, r)
return nil
}
case dns.TypeSOA:
r.(*dns.SOA).Ns = strings.ToLower(r.(*dns.SOA).Ns)
r.(*dns.SOA).Mbox = strings.ToLower(r.(*dns.SOA).Mbox)
z.Apex.SOA = r.(*dns.SOA)
return nil
case dns.TypeNSEC3, dns.TypeNSEC3PARAM:
return fmt.Errorf("NSEC3 zone is not supported, dropping RR: %s for zone: %s", r.Header().Name, z.origin)
case dns.TypeRRSIG:
x := r.(*dns.RRSIG)
switch x.TypeCovered {
case dns.TypeSOA:
z.Apex.SIGSOA = append(z.Apex.SIGSOA, x)
return nil
case dns.TypeNS:
if r.Header().Name == z.origin {
z.Apex.SIGNS = append(z.Apex.SIGNS, x)
return nil
}
}
case dns.TypeCNAME:
r.(*dns.CNAME).Target = strings.ToLower(r.(*dns.CNAME).Target)
case dns.TypeMX:
r.(*dns.MX).Mx = strings.ToLower(r.(*dns.MX).Mx)
case dns.TypeSRV:
r.(*dns.SRV).Target = strings.ToLower(r.(*dns.SRV).Target)
}
z.Tree.Insert(r)
return nil
}
// Delete deletes r from z.
func (z *Zone) Delete(r dns.RR) { z.Tree.Delete(r) }
// TransferAllowed checks if incoming request for transferring the zone is allowed according to the ACLs.
func (z *Zone) TransferAllowed(req request.Request) bool {
for _, t := range z.TransferTo {
if t == "*" {
return true
}
}
// TODO(miek): future matching against IP/CIDR notations
return false
}
// All returns all records from the zone, the first record will be the SOA record,
// otionally followed by all RRSIG(SOA)s.
func (z *Zone) All() []dns.RR {
z.reloadMu.RLock()
defer z.reloadMu.RUnlock()
records := []dns.RR{}
allNodes := z.Tree.All()
for _, a := range allNodes {
records = append(records, a.All()...)
}
if len(z.Apex.SIGNS) > 0 {
records = append(z.Apex.SIGNS, records...)
}
records = append(z.Apex.NS, records...)
if len(z.Apex.SIGSOA) > 0 {
records = append(z.Apex.SIGSOA, records...)
}
return append([]dns.RR{z.Apex.SOA}, records...)
}
func (z *Zone) Reload(shutdown chan bool) error {
if z.NoReload {
return nil
}
watcher, err := fsnotify.NewWatcher()
if err != nil {
return err
}
err = watcher.Add(path.Dir(z.file))
if err != nil {
return err
}
go func() {
// TODO(miek): needs to be killed on reload.
for {
select {
case event := <-watcher.Events:
if path.Clean(event.Name) == z.file {
reader, err := os.Open(z.file)
if err != nil {
log.Printf("[ERROR] Failed to open `%s' for `%s': %v", z.file, z.origin, err)
continue
}
z.reloadMu.Lock()
zone, err := Parse(reader, z.origin, z.file)
if err != nil {
log.Printf("[ERROR] Failed to parse `%s': %v", z.origin, err)
z.reloadMu.Unlock()
continue
}
// copy elements we need
z.Apex = zone.Apex
z.Tree = zone.Tree
z.reloadMu.Unlock()
log.Printf("[INFO] Successfully reloaded zone `%s'", z.origin)
z.Notify()
}
case <-shutdown:
watcher.Close()
return
}
}
}()
return nil
}
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