caddy/modules/caddytls/dnssolver.go
Matthew Holt 8e42661060
caddytls: Finish upgrading to libdns DNS providers for ACME challenges
Until we finish the migration to the new acme library, we have to bring
the solver type in-house. It's small and temporary.
2020-05-02 17:23:36 -06:00

114 lines
2.9 KiB
Go

// Copyright 2015 Matthew Holt and The Caddy Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package caddytls
import (
"context"
"fmt"
"sync"
"time"
"github.com/go-acme/lego/v3/challenge"
"github.com/go-acme/lego/v3/challenge/dns01"
"github.com/libdns/libdns"
)
// TODO: this is borrowed from https://github.com/mholt/acme - once we
// switch to that acme library, this file will go away
// solver is a type that makes libdns providers usable as ACME challenge solvers.
type solver struct {
recordManager
TTL time.Duration
txtRecords map[string]libdns.Record // keyed by challenge token
txtRecordsMu sync.Mutex
}
func (s *solver) Present(domain, token, keyAuth string) error {
fqdn, value := dns01.GetRecord(domain, keyAuth)
rec := libdns.Record{
Type: "TXT",
Name: fqdn,
Value: value,
TTL: s.TTL,
}
zone, err := dns01.FindZoneByFqdn(fqdn)
if err != nil {
return fmt.Errorf("could not determine zone for domain %q: %v", fqdn, err)
}
results, err := s.recordManager.AppendRecords(context.TODO(), zone, []libdns.Record{rec})
if err != nil {
return err
}
if len(results) != 1 {
return fmt.Errorf("expected one record, got %d: %v", len(results), results)
}
// keep this record handy so we can clean it up more efficiently
s.txtRecordsMu.Lock()
if s.txtRecords == nil {
s.txtRecords = make(map[string]libdns.Record)
}
s.txtRecords[keyAuth] = results[0]
s.txtRecordsMu.Unlock()
// TODO: check for record propagation before continuing (accordig to config)
return nil
}
func (s *solver) CleanUp(domain, token, keyAuth string) error {
fqdn, _ := dns01.GetRecord(domain, keyAuth)
authZone, err := dns01.FindZoneByFqdn(fqdn)
if err != nil {
return err
}
// retrieve the record we created
s.txtRecordsMu.Lock()
txtRec, ok := s.txtRecords[keyAuth]
if !ok {
s.txtRecordsMu.Unlock()
return fmt.Errorf("no memory of presenting a DNS record for %v", domain)
}
s.txtRecordsMu.Unlock()
// clean up the record
_, err = s.recordManager.DeleteRecords(context.TODO(), authZone, []libdns.Record{txtRec})
if err != nil {
return err
}
// once it has been successfully cleaned up, we can forget about it
s.txtRecordsMu.Lock()
delete(s.txtRecords, keyAuth)
s.txtRecordsMu.Unlock()
return nil
}
// recordManager defines the set of operations required for ACME challenges.
type recordManager interface {
libdns.RecordAppender
libdns.RecordDeleter
}
var _ challenge.Provider = (*solver)(nil)