coredns/plugin/sign/file.go
Nathan Currier 626333a1b3
Fix zone parser error handling (#6680)
Signed-off-by: Nathan Currier <nathan.currier@broadcom.com>
2024-07-01 11:27:50 -04:00

92 lines
2.2 KiB
Go

package sign
import (
"fmt"
"io"
"os"
"path/filepath"
"github.com/coredns/coredns/plugin/file"
"github.com/coredns/coredns/plugin/file/tree"
"github.com/miekg/dns"
)
// write writes out the zone file to a temporary file which is then moved into the correct place.
func (s *Signer) write(z *file.Zone) error {
f, err := os.CreateTemp(s.directory, "signed-")
if err != nil {
return err
}
if err := write(f, z); err != nil {
f.Close()
return err
}
f.Close()
return os.Rename(f.Name(), filepath.Join(s.directory, s.signedfile))
}
func write(w io.Writer, z *file.Zone) error {
if _, err := io.WriteString(w, z.Apex.SOA.String()); err != nil {
return err
}
w.Write([]byte("\n")) // RR Stringer() method doesn't include newline, which ends the RR in a zone file, write that here.
for _, rr := range z.Apex.SIGSOA {
io.WriteString(w, rr.String())
w.Write([]byte("\n"))
}
for _, rr := range z.Apex.NS {
io.WriteString(w, rr.String())
w.Write([]byte("\n"))
}
for _, rr := range z.Apex.SIGNS {
io.WriteString(w, rr.String())
w.Write([]byte("\n"))
}
err := z.Walk(func(e *tree.Elem, _ map[uint16][]dns.RR) error {
for _, r := range e.All() {
io.WriteString(w, r.String())
w.Write([]byte("\n"))
}
return nil
})
return err
}
// Parse parses the zone in filename and returns a new Zone or an error. This
// is similar to the Parse function in the *file* plugin. However when parsing
// the record types DNSKEY, RRSIG, CDNSKEY and CDS are *not* included in the returned
// zone (if encountered).
func Parse(f io.Reader, origin, fileName string) (*file.Zone, error) {
zp := dns.NewZoneParser(f, dns.Fqdn(origin), fileName)
zp.SetIncludeAllowed(true)
z := file.NewZone(origin, fileName)
seenSOA := false
for rr, ok := zp.Next(); ok; rr, ok = zp.Next() {
switch rr.(type) {
case *dns.DNSKEY, *dns.RRSIG, *dns.CDNSKEY, *dns.CDS:
continue
case *dns.SOA:
seenSOA = true
if err := z.Insert(rr); err != nil {
return nil, err
}
default:
if err := z.Insert(rr); err != nil {
return nil, err
}
}
}
if !seenSOA {
return nil, fmt.Errorf("file %q has no SOA record", fileName)
}
if err := zp.Err(); err != nil {
return nil, err
}
return z, nil
}