lego/providers/dns/gandiv5/gandiv5.go
2020-03-11 23:51:10 +01:00

179 lines
5.1 KiB
Go

// Package gandiv5 implements a DNS provider for solving the DNS-01 challenge using Gandi LiveDNS api.
package gandiv5
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.livedns.gandi.net/
const (
// defaultBaseURL endpoint is the Gandi API endpoint used by Present and CleanUp.
defaultBaseURL = "https://dns.api.gandi.net/api/v5"
minTTL = 300
)
// Environment variables names.
const (
envNamespace = "GANDIV5_"
EnvAPIKey = envNamespace + "API_KEY"
EnvTTL = envNamespace + "TTL"
EnvPropagationTimeout = envNamespace + "PROPAGATION_TIMEOUT"
EnvPollingInterval = envNamespace + "POLLING_INTERVAL"
EnvHTTPTimeout = envNamespace + "HTTP_TIMEOUT"
)
// inProgressInfo contains information about an in-progress challenge
type inProgressInfo struct {
fieldName string
authZone string
}
// 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, 20*time.Minute),
PollingInterval: env.GetOrDefaultSecond(EnvPollingInterval, 20*time.Second),
HTTPClient: &http.Client{
Timeout: env.GetOrDefaultSecond(EnvHTTPTimeout, 10*time.Second),
},
}
}
// DNSProvider is an implementation of the
// challenge.ProviderTimeout interface that uses Gandi's LiveDNS
// API to manage TXT records for a domain.
type DNSProvider struct {
config *Config
inProgressFQDNs map[string]inProgressInfo
inProgressMu sync.Mutex
// 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: GANDIV5_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("gandiv5: the configuration of the DNS provider is nil")
}
if config.APIKey == "" {
return nil, errors.New("gandiv5: no API Key given")
}
if config.BaseURL == "" {
config.BaseURL = defaultBaseURL
}
if config.TTL < minTTL {
return nil, fmt.Errorf("gandiv5: invalid TTL, TTL (%d) must be greater than %d", config.TTL, minTTL)
}
return &DNSProvider{
config: config,
inProgressFQDNs: make(map[string]inProgressInfo),
findZoneByFqdn: dns01.FindZoneByFqdn,
}, nil
}
// Present creates a TXT record using the specified parameters.
func (d *DNSProvider) Present(domain, token, keyAuth string) error {
fqdn, value := dns01.GetRecord(domain, keyAuth)
// find authZone
authZone, err := d.findZoneByFqdn(fqdn)
if err != nil {
return fmt.Errorf("gandiv5: findZoneByFqdn failure: %w", err)
}
// 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)
}
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()
// add TXT record into authZone
err = d.addTXTRecord(dns01.UnFqdn(authZone), name, value, d.config.TTL)
if err != nil {
return err
}
// save data necessary for CleanUp
d.inProgressFQDNs[fqdn] = inProgressInfo{
authZone: authZone,
fieldName: name,
}
return nil
}
// CleanUp removes the TXT record matching the specified parameters.
func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
fqdn, _ := dns01.GetRecord(domain, keyAuth)
// acquire lock and retrieve 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
}
fieldName := d.inProgressFQDNs[fqdn].fieldName
authZone := d.inProgressFQDNs[fqdn].authZone
delete(d.inProgressFQDNs, fqdn)
// delete TXT record from authZone
err := d.deleteTXTRecord(dns01.UnFqdn(authZone), fieldName)
if err != nil {
return fmt.Errorf("gandiv5: %w", err)
}
return nil
}
// Timeout returns the values (20*time.Minute, 20*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
}