lego/providers/dns/gandi/gandi.go
2020-05-08 19:35:25 +02:00

224 lines
6.6 KiB
Go

// Package gandi implements a DNS provider for solving the DNS-01 challenge using Gandi DNS.
package gandi
import (
"errors"
"fmt"
"net/http"
"strings"
"sync"
"time"
"github.com/go-acme/lego/v3/challenge/dns01"
"github.com/go-acme/lego/v3/platform/config/env"
)
// Gandi API reference: http://doc.rpc.gandi.net/index.html
// Gandi API domain examples: http://doc.rpc.gandi.net/domain/faq.html
const (
// defaultBaseURL Gandi XML-RPC endpoint used by Present and CleanUp
defaultBaseURL = "https://rpc.gandi.net/xmlrpc/"
minTTL = 300
)
// Environment variables names.
const (
envNamespace = "GANDI_"
EnvAPIKey = envNamespace + "API_KEY"
EnvTTL = envNamespace + "TTL"
EnvPropagationTimeout = envNamespace + "PROPAGATION_TIMEOUT"
EnvPollingInterval = envNamespace + "POLLING_INTERVAL"
EnvHTTPTimeout = envNamespace + "HTTP_TIMEOUT"
)
// Config is used to configure the creation of the DNSProvider.
type Config struct {
BaseURL string
APIKey string
PropagationTimeout time.Duration
PollingInterval time.Duration
TTL int
HTTPClient *http.Client
}
// NewDefaultConfig returns a default configuration for the DNSProvider.
func NewDefaultConfig() *Config {
return &Config{
TTL: env.GetOrDefaultInt(EnvTTL, minTTL),
PropagationTimeout: env.GetOrDefaultSecond(EnvPropagationTimeout, 40*time.Minute),
PollingInterval: env.GetOrDefaultSecond(EnvPollingInterval, 60*time.Second),
HTTPClient: &http.Client{
Timeout: env.GetOrDefaultSecond(EnvHTTPTimeout, 60*time.Second),
},
}
}
// inProgressInfo contains information about an in-progress challenge.
type inProgressInfo struct {
zoneID int // zoneID of gandi zone to restore in CleanUp
newZoneID int // zoneID of temporary gandi zone containing TXT record
authZone string // the domain name registered at gandi with trailing "."
}
// DNSProvider implements the challenge.Provider interface.
type DNSProvider struct {
inProgressFQDNs map[string]inProgressInfo
inProgressAuthZones map[string]struct{}
inProgressMu sync.Mutex
config *Config
// findZoneByFqdn determines the DNS zone of an fqdn. It is overridden during tests.
findZoneByFqdn func(fqdn string) (string, error)
}
// NewDNSProvider returns a DNSProvider instance configured for Gandi.
// Credentials must be passed in the environment variable: GANDI_API_KEY.
func NewDNSProvider() (*DNSProvider, error) {
values, err := env.Get(EnvAPIKey)
if err != nil {
return nil, fmt.Errorf("gandi: %w", err)
}
config := NewDefaultConfig()
config.APIKey = values[EnvAPIKey]
return NewDNSProviderConfig(config)
}
// NewDNSProviderConfig return a DNSProvider instance configured for Gandi.
func NewDNSProviderConfig(config *Config) (*DNSProvider, error) {
if config == nil {
return nil, errors.New("gandi: the configuration of the DNS provider is nil")
}
if config.APIKey == "" {
return nil, errors.New("gandi: no API Key given")
}
if config.BaseURL == "" {
config.BaseURL = defaultBaseURL
}
return &DNSProvider{
config: config,
inProgressFQDNs: make(map[string]inProgressInfo),
inProgressAuthZones: make(map[string]struct{}),
findZoneByFqdn: dns01.FindZoneByFqdn,
}, nil
}
// Present creates a TXT record using the specified parameters. It
// does this by creating and activating a new temporary Gandi DNS
// zone. This new zone contains the TXT record.
func (d *DNSProvider) Present(domain, token, keyAuth string) error {
fqdn, value := dns01.GetRecord(domain, keyAuth)
if d.config.TTL < minTTL {
d.config.TTL = minTTL // 300 is gandi minimum value for ttl
}
// find authZone and Gandi zone_id for fqdn
authZone, err := d.findZoneByFqdn(fqdn)
if err != nil {
return fmt.Errorf("gandi: findZoneByFqdn failure: %w", err)
}
zoneID, err := d.getZoneID(authZone)
if err != nil {
return fmt.Errorf("gandi: %w", err)
}
// 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)
}
name := fqdn[:len(fqdn)-len("."+authZone)]
// acquire lock and check there is not a challenge already in
// progress for this value of authZone
d.inProgressMu.Lock()
defer d.inProgressMu.Unlock()
if _, ok := d.inProgressAuthZones[authZone]; ok {
return fmt.Errorf("gandi: challenge already in progress for authZone %s", authZone)
}
// perform API actions to create and activate new gandi zone
// containing the required TXT record
newZoneName := fmt.Sprintf("%s [ACME Challenge %s]", dns01.UnFqdn(authZone), time.Now().Format(time.RFC822Z))
newZoneID, err := d.cloneZone(zoneID, newZoneName)
if err != nil {
return err
}
newZoneVersion, err := d.newZoneVersion(newZoneID)
if err != nil {
return fmt.Errorf("gandi: %w", err)
}
err = d.addTXTRecord(newZoneID, newZoneVersion, name, value, d.config.TTL)
if err != nil {
return fmt.Errorf("gandi: %w", err)
}
err = d.setZoneVersion(newZoneID, newZoneVersion)
if err != nil {
return fmt.Errorf("gandi: %w", err)
}
err = d.setZone(authZone, newZoneID)
if err != nil {
return fmt.Errorf("gandi: %w", err)
}
// save data necessary for CleanUp
d.inProgressFQDNs[fqdn] = inProgressInfo{
zoneID: zoneID,
newZoneID: newZoneID,
authZone: authZone,
}
d.inProgressAuthZones[authZone] = struct{}{}
return nil
}
// CleanUp removes the TXT record matching the specified
// parameters. It does this by restoring the old Gandi DNS zone and
// removing the temporary one created by Present.
func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
fqdn, _ := dns01.GetRecord(domain, keyAuth)
// acquire lock and retrieve zoneID, newZoneID and authZone
d.inProgressMu.Lock()
defer d.inProgressMu.Unlock()
if _, ok := d.inProgressFQDNs[fqdn]; !ok {
// if there is no cleanup information then just return
return nil
}
zoneID := d.inProgressFQDNs[fqdn].zoneID
newZoneID := d.inProgressFQDNs[fqdn].newZoneID
authZone := d.inProgressFQDNs[fqdn].authZone
delete(d.inProgressFQDNs, fqdn)
delete(d.inProgressAuthZones, authZone)
// perform API actions to restore old gandi zone for authZone
err := d.setZone(authZone, zoneID)
if err != nil {
return fmt.Errorf("gandi: %w", err)
}
return d.deleteZone(newZoneID)
}
// Timeout returns the values (40*time.Minute, 60*time.Second) which
// are used by the acme package as timeout and check interval values
// when checking for DNS record propagation with Gandi.
func (d *DNSProvider) Timeout() (timeout, interval time.Duration) {
return d.config.PropagationTimeout, d.config.PollingInterval
}