fix: return an error when extracting record name (#1766)

challenge/dns01/domain.go

@@ -0,0 +1,24 @@
+package dns01
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/miekg/dns"
+)
+
+// ExtractSubDomain extracts the subdomain part from a domain and a zone.
+func ExtractSubDomain(domain, zone string) (string, error) {
+	canonDomain := dns.Fqdn(domain)
+	canonZone := dns.Fqdn(zone)
+
+	if canonDomain == canonZone {
+		return "", fmt.Errorf("no subdomain because the domain and the zone are identical: %s", canonDomain)
+	}
+
+	if !dns.IsSubDomain(canonZone, canonDomain) {
+		return "", fmt.Errorf("%s is not a subdomain of %s", canonDomain, canonZone)
+	}
+
+	return strings.TrimSuffix(canonDomain, "."+canonZone), nil
+}

challenge/dns01/domain_test.go

@@ -0,0 +1,104 @@
+package dns01
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestExtractSubDomain(t *testing.T) {
+	testCases := []struct {
+		desc     string
+		domain   string
+		zone     string
+		expected string
+	}{
+		{
+			desc:     "no FQDN",
+			domain:   "_acme-challenge.example.com",
+			zone:     "example.com",
+			expected: "_acme-challenge",
+		},
+		{
+			desc:     "no FQDN zone",
+			domain:   "_acme-challenge.example.com.",
+			zone:     "example.com",
+			expected: "_acme-challenge",
+		},
+		{
+			desc:     "no FQDN domain",
+			domain:   "_acme-challenge.example.com",
+			zone:     "example.com.",
+			expected: "_acme-challenge",
+		},
+		{
+			desc:     "FQDN",
+			domain:   "_acme-challenge.example.com.",
+			zone:     "example.com.",
+			expected: "_acme-challenge",
+		},
+		{
+			desc:     "multi-level subdomain",
+			domain:   "_acme-challenge.one.example.com.",
+			zone:     "example.com.",
+			expected: "_acme-challenge.one",
+		},
+	}
+
+	for _, test := range testCases {
+		test := test
+		t.Run(test.desc, func(t *testing.T) {
+			t.Parallel()
+
+			subDomain, err := ExtractSubDomain(test.domain, test.zone)
+			require.NoError(t, err)
+
+			assert.Equal(t, test.expected, subDomain)
+		})
+	}
+}
+
+func TestExtractSubDomain_errors(t *testing.T) {
+	testCases := []struct {
+		desc   string
+		domain string
+		zone   string
+	}{
+		{
+			desc:   "same domain",
+			domain: "example.com",
+			zone:   "example.com",
+		},
+		{
+			desc:   "same domain, no FQDN zone",
+			domain: "example.com.",
+			zone:   "example.com",
+		},
+		{
+			desc:   "same domain, no FQDN domain",
+			domain: "example.com",
+			zone:   "example.com.",
+		},
+		{
+			desc:   "same domain, FQDN",
+			domain: "example.com.",
+			zone:   "example.com.",
+		},
+		{
+			desc:   "zone and domain are unrelated",
+			domain: "_acme-challenge.example.com",
+			zone:   "example.org",
+		},
+	}
+
+	for _, test := range testCases {
+		test := test
+		t.Run(test.desc, func(t *testing.T) {
+			t.Parallel()
+
+			_, err := ExtractSubDomain(test.domain, test.zone)
+			require.Error(t, err)
+		})
+	}
+}

providers/dns/alidns/alidns.go

@@ -4,7 +4,6 @@ package alidns
 import (
 	"errors"
 	"fmt"
-	"strings"
 	"time"
 
 	"github.com/aliyun/alibaba-cloud-sdk-go/sdk"
@@ -269,9 +268,10 @@ func extractRecordName(fqdn, zone string) (string, error) {
 		return "", fmt.Errorf("fail to convert punycode: %w", err)
 	}
 
-	name := dns01.UnFqdn(fqdn)
-	if idx := strings.Index(name, "."+asciiDomain); idx != -1 {
-		return name[:idx], nil
+	subDomain, err := dns01.ExtractSubDomain(fqdn, asciiDomain)
+	if err != nil {
+		return "", err
 	}
-	return name, nil
+
+	return subDomain, nil
 }

providers/dns/arvancloud/arvancloud.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"fmt"
 	"net/http"
-	"strings"
 	"sync"
 	"time"
 
@@ -114,9 +113,14 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 		return err
 	}
 
+	subDomain, err := dns01.ExtractSubDomain(fqdn, authZone)
+	if err != nil {
+		return fmt.Errorf("arvancloud: %w", err)
+	}
+
 	record := internal.DNSRecord{
 		Type:          "txt",
-		Name:          extractRecordName(fqdn, authZone),
+		Name:          subDomain,
 		Value:         internal.TXTRecordValue{Text: value},
 		TTL:           d.config.TTL,
 		UpstreamHTTPS: "default",
@@ -176,11 +180,3 @@ func getZone(fqdn string) (string, error) {
 
 	return dns01.UnFqdn(authZone), nil
 }
-
-func extractRecordName(fqdn, zone string) string {
-	name := dns01.UnFqdn(fqdn)
-	if idx := strings.Index(name, "."+zone); idx != -1 {
-		return name[:idx]
-	}
-	return name
-}

providers/dns/civo/civo.go

@@ -4,7 +4,6 @@ package civo
 import (
 	"errors"
 	"fmt"
-	"strings"
 	"time"
 
 	"github.com/civo/civogo"
@@ -104,8 +103,13 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 		return fmt.Errorf("civo: %w", err)
 	}
 
+	subDomain, err := dns01.ExtractSubDomain(fqdn, zone)
+	if err != nil {
+		return fmt.Errorf("civo: %w", err)
+	}
+
 	_, err = d.client.CreateDNSRecord(dnsDomain.ID, &civogo.DNSRecordConfig{
-		Name:  extractRecordName(fqdn, zone),
+		Name:  subDomain,
 		Value: value,
 		Type:  civogo.DNSRecordTypeTXT,
 		TTL:   d.config.TTL,
@@ -136,9 +140,14 @@ func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
 		return fmt.Errorf("civo: %w", err)
 	}
 
+	subDomain, err := dns01.ExtractSubDomain(fqdn, zone)
+	if err != nil {
+		return fmt.Errorf("civo: %w", err)
+	}
+
 	var dnsRecord civogo.DNSRecord
 	for _, entry := range dnsRecords {
-		if entry.Name == extractRecordName(fqdn, zone) && entry.Value == value {
+		if entry.Name == subDomain && entry.Value == value {
 			dnsRecord = entry
 			break
 		}
@@ -166,11 +175,3 @@ func getZone(fqdn string) (string, error) {
 
 	return dns01.UnFqdn(authZone), nil
 }
-
-func extractRecordName(fqdn, zone string) string {
-	name := dns01.UnFqdn(fqdn)
-	if idx := strings.Index(name, "."+zone); idx != -1 {
-		return name[:idx]
-	}
-	return name
-}

providers/dns/constellix/constellix.go

@@ -109,7 +109,10 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 		return fmt.Errorf("constellix: failed to get domain (%s): %w", authZone, err)
 	}
 
-	recordName := getRecordName(fqdn, authZone)
+	recordName, err := dns01.ExtractSubDomain(fqdn, authZone)
+	if err != nil {
+		return fmt.Errorf("constellix: %w", err)
+	}
 
 	records, err := d.client.TxtRecords.Search(dom.ID, internal.Exact, recordName)
 	if err != nil {
@@ -147,7 +150,10 @@ func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
 		return fmt.Errorf("constellix: failed to get domain (%s): %w", authZone, err)
 	}
 
-	recordName := getRecordName(fqdn, authZone)
+	recordName, err := dns01.ExtractSubDomain(fqdn, authZone)
+	if err != nil {
+		return fmt.Errorf("constellix: %w", err)
+	}
 
 	records, err := d.client.TxtRecords.Search(dom.ID, internal.Exact, recordName)
 	if err != nil {
@@ -262,7 +268,3 @@ func containsValue(record *internal.Record, value string) bool {
 
 	return false
 }
-
-func getRecordName(fqdn, authZone string) string {
-	return fqdn[0 : len(fqdn)-len(authZone)-1]
-}

providers/dns/desec/desec.go

@@ -109,7 +109,10 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 		return fmt.Errorf("desec: could not find zone for domain %q and fqdn %q : %w", domain, fqdn, err)
 	}
 
-	recordName := getRecordName(fqdn, authZone)
+	recordName, err := dns01.ExtractSubDomain(fqdn, authZone)
+	if err != nil {
+		return fmt.Errorf("desec: %w", err)
+	}
 
 	domainName := dns01.UnFqdn(authZone)
 
@@ -156,7 +159,10 @@ func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
 		return fmt.Errorf("desec: could not find zone for domain %q and fqdn %q : %w", domain, fqdn, err)
 	}
 
-	recordName := getRecordName(fqdn, authZone)
+	recordName, err := dns01.ExtractSubDomain(fqdn, authZone)
+	if err != nil {
+		return fmt.Errorf("desec: %w", err)
+	}
 
 	domainName := dns01.UnFqdn(authZone)
 
@@ -179,7 +185,3 @@ func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
 
 	return nil
 }
-
-func getRecordName(fqdn, authZone string) string {
-	return fqdn[0 : len(fqdn)-len(authZone)-1]
-}

providers/dns/dnsimple/dnsimple.go

@@ -6,7 +6,6 @@ import (
 	"errors"
 	"fmt"
 	"strconv"
-	"strings"
 	"time"
 
 	"github.com/dnsimple/dnsimple-go/dnsimple"
@@ -103,7 +102,11 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 		return fmt.Errorf("dnsimple: %w", err)
 	}
 
-	recordAttributes := newTxtRecord(zoneName, fqdn, value, d.config.TTL)
+	recordAttributes, err := newTxtRecord(zoneName, fqdn, value, d.config.TTL)
+	if err != nil {
+		return fmt.Errorf("dnsimple: %w", err)
+	}
+
 	_, err = d.client.Zones.CreateRecord(context.Background(), accountID, zoneName, recordAttributes)
 	if err != nil {
 		return fmt.Errorf("dnsimple: API call failed: %w", err)
@@ -186,9 +189,12 @@ func (d *DNSProvider) findTxtRecords(fqdn string) ([]dnsimple.ZoneRecord, error)
 		return nil, err
 	}
 
-	recordName := extractRecordName(fqdn, zoneName)
+	subDomain, err := dns01.ExtractSubDomain(fqdn, zoneName)
+	if err != nil {
+		return nil, err
+	}
 
-	result, err := d.client.Zones.ListRecords(context.Background(), accountID, zoneName, &dnsimple.ZoneRecordListOptions{Name: &recordName, Type: dnsimple.String("TXT"), ListOptions: dnsimple.ListOptions{}})
+	result, err := d.client.Zones.ListRecords(context.Background(), accountID, zoneName, &dnsimple.ZoneRecordListOptions{Name: &subDomain, Type: dnsimple.String("TXT"), ListOptions: dnsimple.ListOptions{}})
 	if err != nil {
 		return nil, fmt.Errorf("API call has failed: %w", err)
 	}
@@ -196,23 +202,18 @@ func (d *DNSProvider) findTxtRecords(fqdn string) ([]dnsimple.ZoneRecord, error)
 	return result.Data, nil
 }
 
-func newTxtRecord(zoneName, fqdn, value string, ttl int) dnsimple.ZoneRecordAttributes {
-	name := extractRecordName(fqdn, zoneName)
+func newTxtRecord(zoneName, fqdn, value string, ttl int) (dnsimple.ZoneRecordAttributes, error) {
+	subDomain, err := dns01.ExtractSubDomain(fqdn, zoneName)
+	if err != nil {
+		return dnsimple.ZoneRecordAttributes{}, err
+	}
 
 	return dnsimple.ZoneRecordAttributes{
 		Type:    "TXT",
-		Name:    &name,
+		Name:    &subDomain,
 		Content: value,
 		TTL:     ttl,
-	}
-}
-
-func extractRecordName(fqdn, zone string) string {
-	name := dns01.UnFqdn(fqdn)
-	if idx := strings.Index(name, "."+zone); idx != -1 {
-		return name[:idx]
-	}
-	return name
+	}, nil
 }
 
 func (d *DNSProvider) getAccountID() (string, error) {

providers/dns/dnspod/dnspod.go

@@ -6,7 +6,6 @@ import (
 	"fmt"
 	"net/http"
 	"strconv"
-	"strings"
 	"time"
 
 	"github.com/go-acme/lego/v4/challenge/dns01"
@@ -94,7 +93,11 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 		return err
 	}
 
-	recordAttributes := d.newTxtRecord(zoneName, fqdn, value, d.config.TTL)
+	recordAttributes, err := d.newTxtRecord(zoneName, fqdn, value, d.config.TTL)
+	if err != nil {
+		return err
+	}
+
 	_, _, err = d.client.Records.Create(zoneID, *recordAttributes)
 	if err != nil {
 		return fmt.Errorf("API call failed: %w", err)
@@ -157,40 +160,38 @@ func (d *DNSProvider) getHostedZone(domain string) (string, string, error) {
 	return hostedZone.ID.String(), hostedZone.Name, nil
 }
 
-func (d *DNSProvider) newTxtRecord(zone, fqdn, value string, ttl int) *dnspod.Record {
-	name := extractRecordName(fqdn, zone)
+func (d *DNSProvider) newTxtRecord(zone, fqdn, value string, ttl int) (*dnspod.Record, error) {
+	subDomain, err := dns01.ExtractSubDomain(fqdn, zone)
+	if err != nil {
+		return nil, err
+	}
 
 	return &dnspod.Record{
 		Type:  "TXT",
-		Name:  name,
+		Name:  subDomain,
 		Value: value,
 		Line:  "默认",
 		TTL:   strconv.Itoa(ttl),
-	}
+	}, nil
 }
 
 func (d *DNSProvider) findTxtRecords(fqdn, zoneID, zoneName string) ([]dnspod.Record, error) {
-	recordName := extractRecordName(fqdn, zoneName)
+	subDomain, err := dns01.ExtractSubDomain(fqdn, zoneName)
+	if err != nil {
+		return nil, err
+	}
 
 	var records []dnspod.Record
-	result, _, err := d.client.Records.List(zoneID, recordName)
+	result, _, err := d.client.Records.List(zoneID, subDomain)
 	if err != nil {
 		return records, fmt.Errorf("API call has failed: %w", err)
 	}
 
 	for _, record := range result {
-		if record.Name == recordName {
+		if record.Name == subDomain {
 			records = append(records, record)
 		}
 	}
 
 	return records, nil
 }
-
-func extractRecordName(fqdn, zone string) string {
-	name := dns01.UnFqdn(fqdn)
-	if idx := strings.Index(name, "."+zone); idx != -1 {
-		return name[:idx]
-	}
-	return name
-}

providers/dns/exoscale/exoscale.go

@@ -254,8 +254,10 @@ func (d *DNSProvider) findZoneAndRecordName(fqdn string) (string, string, error)
 
 	zone = dns01.UnFqdn(zone)
 
-	name := dns01.UnFqdn(fqdn)
-	name = name[:len(name)-len("."+zone)]
+	subDomain, err := dns01.ExtractSubDomain(fqdn, zone)
+	if err != nil {
+		return "", "", err
+	}
 
-	return zone, name, nil
+	return zone, subDomain, nil
 }

providers/dns/gandi/gandi.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"fmt"
 	"net/http"
-	"strings"
 	"sync"
 	"time"
 
@@ -131,11 +130,10 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 	}
 
 	// determine name of TXT record
-	if !strings.HasSuffix(
-		strings.ToLower(fqdn), strings.ToLower("."+authZone)) {
-		return fmt.Errorf("gandi: unexpected authZone %s for fqdn %s", authZone, fqdn)
+	subDomain, err := dns01.ExtractSubDomain(fqdn, authZone)
+	if err != nil {
+		return fmt.Errorf("gandi: %w", err)
 	}
-	name := fqdn[:len(fqdn)-len("."+authZone)]
 
 	// acquire lock and check there is not a challenge already in
 	// progress for this value of authZone
@@ -160,7 +158,7 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 		return fmt.Errorf("gandi: %w", err)
 	}
 
-	err = d.addTXTRecord(newZoneID, newZoneVersion, name, value, d.config.TTL)
+	err = d.addTXTRecord(newZoneID, newZoneVersion, subDomain, value, d.config.TTL)
 	if err != nil {
 		return fmt.Errorf("gandi: %w", err)
 	}

providers/dns/gandiv5/gandiv5.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"fmt"
 	"net/http"
-	"strings"
 	"sync"
 	"time"
 
@@ -120,11 +119,10 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 	}
 
 	// determine name of TXT record
-	if !strings.HasSuffix(
-		strings.ToLower(fqdn), strings.ToLower("."+authZone)) {
-		return fmt.Errorf("gandiv5: unexpected authZone %s for fqdn %s", authZone, fqdn)
+	subDomain, err := dns01.ExtractSubDomain(fqdn, authZone)
+	if err != nil {
+		return fmt.Errorf("gandiv5: %w", err)
 	}
-	name := fqdn[:len(fqdn)-len("."+authZone)]
 
 	// acquire lock and check there is not a challenge already in
 	// progress for this value of authZone
@@ -132,7 +130,7 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 	defer d.inProgressMu.Unlock()
 
 	// add TXT record into authZone
-	err = d.addTXTRecord(dns01.UnFqdn(authZone), name, value, d.config.TTL)
+	err = d.addTXTRecord(dns01.UnFqdn(authZone), subDomain, value, d.config.TTL)
 	if err != nil {
 		return err
 	}
@@ -140,7 +138,7 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 	// save data necessary for CleanUp
 	d.inProgressFQDNs[fqdn] = inProgressInfo{
 		authZone:  authZone,
-		fieldName: name,
+		fieldName: subDomain,
 	}
 	return nil
 }

providers/dns/glesys/glesys.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"fmt"
 	"net/http"
-	"strings"
 	"sync"
 	"time"
 
@@ -107,12 +106,10 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 		return fmt.Errorf("glesys: findZoneByFqdn failure: %w", err)
 	}
 
-	// determine name of TXT record
-	if !strings.HasSuffix(
-		strings.ToLower(fqdn), strings.ToLower("."+authZone)) {
-		return fmt.Errorf("glesys: unexpected authZone %s for fqdn %s", authZone, fqdn)
+	subDomain, err := dns01.ExtractSubDomain(fqdn, authZone)
+	if err != nil {
+		return fmt.Errorf("glesys: %w", err)
 	}
-	name := fqdn[:len(fqdn)-len("."+authZone)]
 
 	// acquire lock and check there is not a challenge already in
 	// progress for this value of authZone
@@ -121,7 +118,7 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 
 	// add TXT record into authZone
 	// TODO(ldez) replace domain by FQDN to follow CNAME.
-	recordID, err := d.addTXTRecord(domain, dns01.UnFqdn(authZone), name, value, d.config.TTL)
+	recordID, err := d.addTXTRecord(domain, dns01.UnFqdn(authZone), subDomain, value, d.config.TTL)
 	if err != nil {
 		return err
 	}

providers/dns/godaddy/godaddy.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"fmt"
 	"net/http"
-	"strings"
 	"time"
 
 	"github.com/go-acme/lego/v4/challenge/dns01"
@@ -110,9 +109,12 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 		return fmt.Errorf("godaddy: failed to get zone: %w", err)
 	}
 
-	recordName := extractRecordName(fqdn, domainZone)
+	subDomain, err := dns01.ExtractSubDomain(fqdn, domainZone)
+	if err != nil {
+		return fmt.Errorf("godaddy: %w", err)
+	}
 
-	records, err := d.client.GetRecords(domainZone, "TXT", recordName)
+	records, err := d.client.GetRecords(domainZone, "TXT", subDomain)
 	if err != nil {
 		return fmt.Errorf("godaddy: failed to get TXT records: %w", err)
 	}
@@ -126,13 +128,13 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 
 	record := internal.DNSRecord{
 		Type: "TXT",
-		Name: recordName,
+		Name: subDomain,
 		Data: value,
 		TTL:  d.config.TTL,
 	}
 	newRecords = append(newRecords, record)
 
-	err = d.client.UpdateTxtRecords(newRecords, domainZone, recordName)
+	err = d.client.UpdateTxtRecords(newRecords, domainZone, subDomain)
 	if err != nil {
 		return fmt.Errorf("godaddy: failed to add TXT record: %w", err)
 	}
@@ -149,9 +151,12 @@ func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
 		return fmt.Errorf("godaddy: failed to get zone: %w", err)
 	}
 
-	recordName := extractRecordName(fqdn, domainZone)
+	subDomain, err := dns01.ExtractSubDomain(fqdn, domainZone)
+	if err != nil {
+		return fmt.Errorf("godaddy: %w", err)
+	}
 
-	records, err := d.client.GetRecords(domainZone, "TXT", recordName)
+	records, err := d.client.GetRecords(domainZone, "TXT", subDomain)
 	if err != nil {
 		return fmt.Errorf("godaddy: failed to get TXT records: %w", err)
 	}
@@ -186,14 +191,6 @@ func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
 	return nil
 }
 
-func extractRecordName(fqdn, zone string) string {
-	name := dns01.UnFqdn(fqdn)
-	if idx := strings.Index(name, "."+zone); idx != -1 {
-		return name[:idx]
-	}
-	return name
-}
-
 func getZone(fqdn string) (string, error) {
 	authZone, err := dns01.FindZoneByFqdn(fqdn)
 	if err != nil {

providers/dns/hetzner/hetzner.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"fmt"
 	"net/http"
-	"strings"
 	"time"
 
 	"github.com/go-acme/lego/v4/challenge/dns01"
@@ -111,9 +110,14 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 		return fmt.Errorf("hetzner: %w", err)
 	}
 
+	subDomain, err := dns01.ExtractSubDomain(fqdn, zone)
+	if err != nil {
+		return fmt.Errorf("hetzner: %w", err)
+	}
+
 	record := internal.DNSRecord{
 		Type:   "TXT",
-		Name:   extractRecordName(fqdn, zone),
+		Name:   subDomain,
 		Value:  value,
 		TTL:    d.config.TTL,
 		ZoneID: zoneID,
@@ -140,9 +144,12 @@ func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
 		return fmt.Errorf("hetzner: %w", err)
 	}
 
-	recordName := extractRecordName(fqdn, zone)
+	subDomain, err := dns01.ExtractSubDomain(fqdn, zone)
+	if err != nil {
+		return fmt.Errorf("hetzner: %w", err)
+	}
 
-	record, err := d.client.GetTxtRecord(recordName, value, zoneID)
+	record, err := d.client.GetTxtRecord(subDomain, value, zoneID)
 	if err != nil {
 		return fmt.Errorf("hetzner: %w", err)
 	}
@@ -154,14 +161,6 @@ func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
 	return nil
 }
 
-func extractRecordName(fqdn, zone string) string {
-	name := dns01.UnFqdn(fqdn)
-	if idx := strings.Index(name, "."+zone); idx != -1 {
-		return name[:idx]
-	}
-	return name
-}
-
 func getZone(fqdn string) (string, error) {
 	authZone, err := dns01.FindZoneByFqdn(fqdn)
 	if err != nil {

providers/dns/infomaniak/infomaniak.go

@@ -122,8 +122,13 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 	d.domainIDs[token] = ikDomain.ID
 	d.domainIDsMu.Unlock()
 
+	subDomain, err := dns01.ExtractSubDomain(fqdn, ikDomain.CustomerName)
+	if err != nil {
+		return fmt.Errorf("infomaniak: %w", err)
+	}
+
 	record := internal.Record{
-		Source: extractRecordName(fqdn, ikDomain.CustomerName),
+		Source: subDomain,
 		Target: value,
 		Type:   "TXT",
 		TTL:    d.config.TTL,
@@ -184,9 +189,3 @@ func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
 func (d *DNSProvider) Timeout() (timeout, interval time.Duration) {
 	return d.config.PropagationTimeout, d.config.PollingInterval
 }
-
-func extractRecordName(fqdn, domain string) string {
-	name := dns01.UnFqdn(fqdn)
-
-	return name[:len(name)-len(domain)-1]
-}

providers/dns/mythicbeasts/mythicbeasts.go

@@ -114,7 +114,10 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 		return fmt.Errorf("mythicbeasts: %w", err)
 	}
 
-	leaf := fqdn[:len(fqdn)-(len(authZone)+1)]
+	subDomain, err := dns01.ExtractSubDomain(fqdn, authZone)
+	if err != nil {
+		return fmt.Errorf("mythicbeasts: %w", err)
+	}
 
 	authZone = dns01.UnFqdn(authZone)
 
@@ -123,7 +126,7 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 		return fmt.Errorf("mythicbeasts: %w", err)
 	}
 
-	err = d.createTXTRecord(authZone, leaf, value)
+	err = d.createTXTRecord(authZone, subDomain, value)
 	if err != nil {
 		return fmt.Errorf("mythicbeasts: %w", err)
 	}
@@ -140,7 +143,10 @@ func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
 		return fmt.Errorf("mythicbeasts: %w", err)
 	}
 
-	leaf := fqdn[:len(fqdn)-(len(authZone)+1)]
+	subDomain, err := dns01.ExtractSubDomain(fqdn, authZone)
+	if err != nil {
+		return fmt.Errorf("mythicbeasts: %w", err)
+	}
 
 	authZone = dns01.UnFqdn(authZone)
 
@@ -149,7 +155,7 @@ func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
 		return fmt.Errorf("mythicbeasts: %w", err)
 	}
 
-	err = d.removeTXTRecord(authZone, leaf, value)
+	err = d.removeTXTRecord(authZone, subDomain, value)
 	if err != nil {
 		return fmt.Errorf("mythicbeasts: %w", err)
 	}

providers/dns/namedotcom/namedotcom.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"fmt"
 	"net/http"
-	"strings"
 	"time"
 
 	"github.com/go-acme/lego/v4/challenge/dns01"
@@ -111,13 +110,18 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 	// TODO(ldez) replace domain by FQDN to follow CNAME.
 	domainDetails, err := d.client.GetDomain(&namecom.GetDomainRequest{DomainName: domain})
 	if err != nil {
-		return fmt.Errorf("namedotcom API call failed: %w", err)
+		return fmt.Errorf("namedotcom: API call failed: %w", err)
+	}
+
+	subDomain, err := dns01.ExtractSubDomain(fqdn, domainDetails.DomainName)
+	if err != nil {
+		return fmt.Errorf("namedotcom: %w", err)
 	}
 
 	// TODO(ldez) replace domain by FQDN to follow CNAME.
 	request := &namecom.Record{
 		DomainName: domain,
-		Host:       extractRecordName(fqdn, domainDetails.DomainName),
+		Host:       subDomain,
 		Type:       "TXT",
 		TTL:        uint32(d.config.TTL),
 		Answer:     value,
@@ -183,11 +187,3 @@ func (d *DNSProvider) getRecords(domain string) ([]*namecom.Record, error) {
 
 	return records, nil
 }
-
-func extractRecordName(fqdn, zone string) string {
-	name := dns01.UnFqdn(fqdn)
-	if idx := strings.Index(name, "."+zone); idx != -1 {
-		return name[:idx]
-	}
-	return name
-}

providers/dns/namesilo/namesilo.go

@@ -4,7 +4,6 @@ package namesilo
 import (
 	"errors"
 	"fmt"
-	"strings"
 	"time"
 
 	"github.com/go-acme/lego/v4/challenge/dns01"
@@ -94,10 +93,15 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 		return fmt.Errorf("namesilo: %w", err)
 	}
 
+	subdomain, err := dns01.ExtractSubDomain(fqdn, zoneName)
+	if err != nil {
+		return fmt.Errorf("namesilo: %w", err)
+	}
+
 	_, err = d.client.DnsAddRecord(&namesilo.DnsAddRecordParams{
 		Domain: zoneName,
 		Type:   "TXT",
-		Host:   getRecordName(fqdn, zoneName),
+		Host:   subdomain,
 		Value:  value,
 		TTL:    d.config.TTL,
 	})
@@ -121,10 +125,14 @@ func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
 		return fmt.Errorf("namesilo: %w", err)
 	}
 
+	subdomain, err := dns01.ExtractSubDomain(fqdn, zoneName)
+	if err != nil {
+		return fmt.Errorf("namesilo: %w", err)
+	}
+
 	var lastErr error
-	name := getRecordName(fqdn, zoneName)
 	for _, r := range resp.Reply.ResourceRecord {
-		if r.Type == "TXT" && (r.Host == name || r.Host == dns01.UnFqdn(fqdn)) {
+		if r.Type == "TXT" && (r.Host == subdomain || r.Host == dns01.UnFqdn(fqdn)) {
 			_, err := d.client.DnsDeleteRecord(&namesilo.DnsDeleteRecordParams{Domain: zoneName, ID: r.RecordID})
 			if err != nil {
 				lastErr = fmt.Errorf("namesilo: %w", err)
@@ -147,7 +155,3 @@ func getZoneNameByDomain(domain string) (string, error) {
 	}
 	return dns01.UnFqdn(zone), nil
 }
-
-func getRecordName(domain, zone string) string {
-	return strings.TrimSuffix(dns01.ToFqdn(domain), "."+dns01.ToFqdn(zone))
-}

providers/dns/nearlyfreespeech/nearlyfreespeech.go

@@ -115,8 +115,13 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 		return fmt.Errorf("nearlyfreespeech: could not determine zone for domain %q: %w", fqdn, err)
 	}
 
+	recordName, err := dns01.ExtractSubDomain(fqdn, authZone)
+	if err != nil {
+		return fmt.Errorf("nearlyfreespeech: %w", err)
+	}
+
 	record := internal.Record{
-		Name: getRecordName(fqdn, authZone),
+		Name: recordName,
 		Type: "TXT",
 		Data: value,
 		TTL:  d.config.TTL,
@@ -139,8 +144,13 @@ func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
 		return fmt.Errorf("nearlyfreespeech: could not determine zone for domain %q: %w", fqdn, err)
 	}
 
+	recordName, err := dns01.ExtractSubDomain(fqdn, authZone)
+	if err != nil {
+		return fmt.Errorf("nearlyfreespeech: %w", err)
+	}
+
 	record := internal.Record{
-		Name: getRecordName(fqdn, authZone),
+		Name: recordName,
 		Type: "TXT",
 		Data: value,
 	}
@@ -152,7 +162,3 @@ func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
 
 	return nil
 }
-
-func getRecordName(fqdn, authZone string) string {
-	return fqdn[0 : len(fqdn)-len(authZone)-1]
-}

providers/dns/ovh/ovh.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"fmt"
 	"net/http"
-	"strings"
 	"sync"
 	"time"
 
@@ -132,7 +131,11 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 	}
 
 	authZone = dns01.UnFqdn(authZone)
-	subDomain := extractRecordName(fqdn, authZone)
+
+	subDomain, err := dns01.ExtractSubDomain(fqdn, authZone)
+	if err != nil {
+		return fmt.Errorf("ovh: %w", err)
+	}
 
 	reqURL := fmt.Sprintf("/domain/zone/%s/record", authZone)
 	reqData := Record{FieldType: "TXT", SubDomain: subDomain, Target: value, TTL: d.config.TTL}
@@ -204,11 +207,3 @@ func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
 func (d *DNSProvider) Timeout() (timeout, interval time.Duration) {
 	return d.config.PropagationTimeout, d.config.PollingInterval
 }
-
-func extractRecordName(fqdn, zone string) string {
-	name := dns01.UnFqdn(fqdn)
-	if idx := strings.Index(name, "."+zone); idx != -1 {
-		return name[:idx]
-	}
-	return ""
-}

providers/dns/sakuracloud/client.go

@@ -3,7 +3,6 @@ package sakuracloud
 import (
 	"context"
 	"fmt"
-	"strings"
 	"sync"
 
 	"github.com/go-acme/lego/v4/challenge/dns01"
@@ -21,17 +20,21 @@ func (d *DNSProvider) addTXTRecord(fqdn, value string, ttl int) error {
 
 	zone, err := d.getHostedZone(fqdn)
 	if err != nil {
-		return fmt.Errorf("%w", err)
+		return err
 	}
 
-	name := extractRecordName(fqdn, zone.Name)
+	subDomain, err := dns01.ExtractSubDomain(fqdn, zone.Name)
+	if err != nil {
+		return err
+	}
 
 	records := append(zone.Records, &iaas.DNSRecord{
-		Name:  name,
+		Name:  subDomain,
 		Type:  "TXT",
 		RData: value,
 		TTL:   ttl,
 	})
+
 	_, err = d.client.UpdateSettings(context.Background(), zone.ID, &iaas.DNSUpdateSettingsRequest{
 		Records:      records,
 		SettingsHash: zone.SettingsHash,
@@ -52,11 +55,14 @@ func (d *DNSProvider) cleanupTXTRecord(fqdn, value string) error {
 		return err
 	}
 
-	recordName := extractRecordName(fqdn, zone.Name)
+	subDomain, err := dns01.ExtractSubDomain(fqdn, zone.Name)
+	if err != nil {
+		return err
+	}
 
 	var updRecords iaas.DNSRecords
 	for _, r := range zone.Records {
-		if !(r.Name == recordName && r.Type == "TXT" && r.RData == value) {
+		if !(r.Name == subDomain && r.Type == "TXT" && r.RData == value) {
 			updRecords = append(updRecords, r)
 		}
 	}
@@ -104,11 +110,3 @@ func (d *DNSProvider) getHostedZone(domain string) (*iaas.DNS, error) {
 
 	return nil, fmt.Errorf("zone %s not found", zoneName)
 }
-
-func extractRecordName(fqdn, zone string) string {
-	name := dns01.UnFqdn(fqdn)
-	if idx := strings.Index(name, "."+zone); idx != -1 {
-		return name[:idx]
-	}
-	return name
-}

providers/dns/servercow/servercow.go

@@ -109,7 +109,10 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 		return fmt.Errorf("servercow: %w", err)
 	}
 
-	recordName := getRecordName(fqdn, authZone)
+	recordName, err := dns01.ExtractSubDomain(fqdn, authZone)
+	if err != nil {
+		return fmt.Errorf("servercow: %w", err)
+	}
 
 	record := findRecords(records, recordName)
 
@@ -162,7 +165,10 @@ func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
 		return fmt.Errorf("servercow: failed to get TXT records: %w", err)
 	}
 
-	recordName := getRecordName(fqdn, authZone)
+	recordName, err := dns01.ExtractSubDomain(fqdn, authZone)
+	if err != nil {
+		return fmt.Errorf("servercow: %w", err)
+	}
 
 	record := findRecords(records, recordName)
 	if record == nil {
@@ -231,7 +237,3 @@ func containsValue(record *internal.Record, value string) bool {
 
 	return false
 }
-
-func getRecordName(fqdn, authZone string) string {
-	return fqdn[0 : len(fqdn)-len(authZone)-2]
-}

providers/dns/stackpath/stackpath.go

@@ -8,7 +8,6 @@ import (
 	"fmt"
 	"net/http"
 	"net/url"
-	"strings"
 	"time"
 
 	"github.com/go-acme/lego/v4/challenge/dns01"
@@ -120,8 +119,13 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 		return fmt.Errorf("stackpath: %w", err)
 	}
 
+	subDomain, err := dns01.ExtractSubDomain(fqdn, zone.Domain)
+	if err != nil {
+		return fmt.Errorf("stackpath: %w", err)
+	}
+
 	record := Record{
-		Name: extractRecordName(fqdn, zone.Domain),
+		Name: subDomain,
 		Type: "TXT",
 		TTL:  d.config.TTL,
 		Data: value,
@@ -139,9 +143,12 @@ func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
 		return fmt.Errorf("stackpath: %w", err)
 	}
 
-	recordName := extractRecordName(fqdn, zone.Domain)
+	subDomain, err := dns01.ExtractSubDomain(fqdn, zone.Domain)
+	if err != nil {
+		return fmt.Errorf("stackpath: %w", err)
+	}
 
-	records, err := d.getZoneRecords(recordName, zone)
+	records, err := d.getZoneRecords(subDomain, zone)
 	if err != nil {
 		return err
 	}
@@ -161,11 +168,3 @@ func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
 func (d *DNSProvider) Timeout() (timeout, interval time.Duration) {
 	return d.config.PropagationTimeout, d.config.PollingInterval
 }
-
-func extractRecordName(fqdn, zone string) string {
-	name := dns01.UnFqdn(fqdn)
-	if idx := strings.Index(name, "."+zone); idx != -1 {
-		return name[:idx]
-	}
-	return name
-}

providers/dns/tencentcloud/client.go

@@ -3,7 +3,6 @@ package tencentcloud
 import (
 	"errors"
 	"fmt"
-	"strings"
 
 	"github.com/go-acme/lego/v4/challenge/dns01"
 	"github.com/tencentcloud/tencentcloud-sdk-go/tencentcloud/common"
@@ -84,9 +83,10 @@ func extractRecordName(fqdn, zone string) (string, error) {
 		return "", fmt.Errorf("fail to convert punycode: %w", err)
 	}
 
-	name := dns01.UnFqdn(fqdn)
-	if idx := strings.Index(name, "."+asciiDomain); idx != -1 {
-		return name[:idx], nil
+	subDomain, err := dns01.ExtractSubDomain(fqdn, asciiDomain)
+	if err != nil {
+		return "", err
 	}
-	return name, nil
+
+	return subDomain, nil
 }

providers/dns/vkcloud/vkcloud.go

@@ -144,9 +144,12 @@ func (r *DNSProvider) Present(domain, _, keyAuth string) error {
 		return fmt.Errorf("vkcloud: cant find dns zone %s in VK Cloud", authZone)
 	}
 
-	name := fqdn[:len(fqdn)-len(authZone)-1]
+	subDomain, err := dns01.ExtractSubDomain(fqdn, authZone)
+	if err != nil {
+		return fmt.Errorf("vkcloud: %w", err)
+	}
 
-	err = r.upsertTXTRecord(zoneUUID, name, value)
+	err = r.upsertTXTRecord(zoneUUID, subDomain, value)
 	if err != nil {
 		return fmt.Errorf("vkcloud: %w", err)
 	}
@@ -182,9 +185,12 @@ func (r *DNSProvider) CleanUp(domain, _, keyAuth string) error {
 		return nil
 	}
 
-	name := fqdn[:len(fqdn)-len(authZone)-1]
+	subDomain, err := dns01.ExtractSubDomain(fqdn, authZone)
+	if err != nil {
+		return fmt.Errorf("vkcloud: %w", err)
+	}
 
-	err = r.removeTXTRecord(zoneUUID, name, value)
+	err = r.removeTXTRecord(zoneUUID, subDomain, value)
 	if err != nil {
 		return fmt.Errorf("vkcloud: %w", err)
 	}

providers/dns/vultr/vultr.go

@@ -105,10 +105,13 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 		return fmt.Errorf("vultr: %w", err)
 	}
 
-	name := extractRecordName(fqdn, zoneDomain)
+	subDomain, err := dns01.ExtractSubDomain(fqdn, zoneDomain)
+	if err != nil {
+		return fmt.Errorf("vultr: %w", err)
+	}
 
 	req := govultr.DomainRecordReq{
-		Name:     name,
+		Name:     subDomain,
 		Type:     "TXT",
 		Data:     `"` + value + `"`,
 		TTL:      d.config.TTL,
@@ -196,6 +199,11 @@ func (d *DNSProvider) findTxtRecords(ctx context.Context, domain, fqdn string) (
 		return "", nil, err
 	}
 
+	subDomain, err := dns01.ExtractSubDomain(fqdn, zoneDomain)
+	if err != nil {
+		return "", nil, err
+	}
+
 	listOptions := &govultr.ListOptions{PerPage: 25}
 
 	var records []govultr.DomainRecord
@@ -205,9 +213,8 @@ func (d *DNSProvider) findTxtRecords(ctx context.Context, domain, fqdn string) (
 			return "", records, fmt.Errorf("API call has failed: %w", err)
 		}
 
-		recordName := extractRecordName(fqdn, zoneDomain)
 		for _, record := range result {
-			if record.Type == "TXT" && record.Name == recordName {
+			if record.Type == "TXT" && record.Name == subDomain {
 				records = append(records, record)
 			}
 		}
@@ -221,11 +228,3 @@ func (d *DNSProvider) findTxtRecords(ctx context.Context, domain, fqdn string) (
 
 	return zoneDomain, records, nil
 }
-
-func extractRecordName(fqdn, zone string) string {
-	name := dns01.UnFqdn(fqdn)
-	if idx := strings.Index(name, "."+zone); idx != -1 {
-		return name[:idx]
-	}
-	return name
-}

providers/dns/yandexcloud/yandexcloud.go

@@ -128,9 +128,12 @@ func (r *DNSProvider) Present(domain, _, keyAuth string) error {
 		return fmt.Errorf("yandexcloud: cant find dns zone %s in yandex cloud", authZone)
 	}
 
-	name := fqdn[:len(fqdn)-len(authZone)-1]
+	subDomain, err := dns01.ExtractSubDomain(fqdn, authZone)
+	if err != nil {
+		return fmt.Errorf("yandexcloud: %w", err)
+	}
 
-	err = r.upsertRecordSetData(ctx, zoneID, name, value)
+	err = r.upsertRecordSetData(ctx, zoneID, subDomain, value)
 	if err != nil {
 		return fmt.Errorf("yandexcloud: %w", err)
 	}
@@ -166,9 +169,12 @@ func (r *DNSProvider) CleanUp(domain, _, keyAuth string) error {
 		return nil
 	}
 
-	name := fqdn[:len(fqdn)-len(authZone)-1]
+	subDomain, err := dns01.ExtractSubDomain(fqdn, authZone)
+	if err != nil {
+		return fmt.Errorf("yandexcloud: %w", err)
+	}
 
-	err = r.removeRecordSetData(ctx, zoneID, name, value)
+	err = r.removeRecordSetData(ctx, zoneID, subDomain, value)
 	if err != nil {
 		return fmt.Errorf("yandexcloud: %w", err)
 	}

providers/dns/zoneee/zoneee.go

@@ -108,7 +108,7 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 	fqdn, value := dns01.GetRecord(domain, keyAuth)
 
 	record := txtRecord{
-		Name:        fqdn[:len(fqdn)-1],
+		Name:        dns01.UnFqdn(fqdn),
 		Destination: value,
 	}