package acme import ( "context" "crypto/tls" "crypto/x509" "errors" "fmt" "net/url" "reflect" "strings" "sync" "time" "github.com/containous/traefik/v2/pkg/config/dynamic" "github.com/containous/traefik/v2/pkg/log" "github.com/containous/traefik/v2/pkg/rules" "github.com/containous/traefik/v2/pkg/safe" traefiktls "github.com/containous/traefik/v2/pkg/tls" "github.com/containous/traefik/v2/pkg/types" "github.com/containous/traefik/v2/pkg/version" "github.com/go-acme/lego/v4/certificate" "github.com/go-acme/lego/v4/challenge" "github.com/go-acme/lego/v4/challenge/dns01" "github.com/go-acme/lego/v4/lego" "github.com/go-acme/lego/v4/providers/dns" "github.com/go-acme/lego/v4/registration" ) // oscpMustStaple enables OSCP stapling as from https://github.com/go-acme/lego/issues/270. var oscpMustStaple = false // Configuration holds ACME configuration provided by users. type Configuration struct { Email string `description:"Email address used for registration." json:"email,omitempty" toml:"email,omitempty" yaml:"email,omitempty"` CAServer string `description:"CA server to use." json:"caServer,omitempty" toml:"caServer,omitempty" yaml:"caServer,omitempty"` PreferredChain string `description:"Preferred chain to use." json:"preferredChain,omitempty" toml:"preferredChain,omitempty" yaml:"preferredChain,omitempty"` Storage string `description:"Storage to use." json:"storage,omitempty" toml:"storage,omitempty" yaml:"storage,omitempty"` KeyType string `description:"KeyType used for generating certificate private key. Allow value 'EC256', 'EC384', 'RSA2048', 'RSA4096', 'RSA8192'." json:"keyType,omitempty" toml:"keyType,omitempty" yaml:"keyType,omitempty"` DNSChallenge *DNSChallenge `description:"Activate DNS-01 Challenge." json:"dnsChallenge,omitempty" toml:"dnsChallenge,omitempty" yaml:"dnsChallenge,omitempty" label:"allowEmpty"` HTTPChallenge *HTTPChallenge `description:"Activate HTTP-01 Challenge." json:"httpChallenge,omitempty" toml:"httpChallenge,omitempty" yaml:"httpChallenge,omitempty" label:"allowEmpty"` TLSChallenge *TLSChallenge `description:"Activate TLS-ALPN-01 Challenge." json:"tlsChallenge,omitempty" toml:"tlsChallenge,omitempty" yaml:"tlsChallenge,omitempty" label:"allowEmpty"` } // SetDefaults sets the default values. func (a *Configuration) SetDefaults() { a.CAServer = lego.LEDirectoryProduction a.Storage = "acme.json" a.KeyType = "RSA4096" } // CertAndStore allows mapping a TLS certificate to a TLS store. type CertAndStore struct { Certificate Store string } // Certificate is a struct which contains all data needed from an ACME certificate. type Certificate struct { Domain types.Domain `json:"domain,omitempty" toml:"domain,omitempty" yaml:"domain,omitempty"` Certificate []byte `json:"certificate,omitempty" toml:"certificate,omitempty" yaml:"certificate,omitempty"` Key []byte `json:"key,omitempty" toml:"key,omitempty" yaml:"key,omitempty"` } // DNSChallenge contains DNS challenge Configuration. type DNSChallenge struct { Provider string `description:"Use a DNS-01 based challenge provider rather than HTTPS." json:"provider,omitempty" toml:"provider,omitempty" yaml:"provider,omitempty"` DelayBeforeCheck types.Duration `description:"Assume DNS propagates after a delay in seconds rather than finding and querying nameservers." json:"delayBeforeCheck,omitempty" toml:"delayBeforeCheck,omitempty" yaml:"delayBeforeCheck,omitempty"` Resolvers []string `description:"Use following DNS servers to resolve the FQDN authority." json:"resolvers,omitempty" toml:"resolvers,omitempty" yaml:"resolvers,omitempty"` DisablePropagationCheck bool `description:"Disable the DNS propagation checks before notifying ACME that the DNS challenge is ready. [not recommended]" json:"disablePropagationCheck,omitempty" toml:"disablePropagationCheck,omitempty" yaml:"disablePropagationCheck,omitempty"` } // HTTPChallenge contains HTTP challenge Configuration. type HTTPChallenge struct { EntryPoint string `description:"HTTP challenge EntryPoint" json:"entryPoint,omitempty" toml:"entryPoint,omitempty" yaml:"entryPoint,omitempty"` } // TLSChallenge contains TLS challenge Configuration. type TLSChallenge struct{} // Provider holds configurations of the provider. type Provider struct { *Configuration ResolverName string Store Store `json:"store,omitempty" toml:"store,omitempty" yaml:"store,omitempty"` ChallengeStore ChallengeStore certificates []*CertAndStore account *Account client *lego.Client certsChan chan *CertAndStore configurationChan chan<- dynamic.Message tlsManager *traefiktls.Manager clientMutex sync.Mutex configFromListenerChan chan dynamic.Configuration pool *safe.Pool resolvingDomains map[string]struct{} resolvingDomainsMutex sync.RWMutex } // SetTLSManager sets the tls manager to use. func (p *Provider) SetTLSManager(tlsManager *traefiktls.Manager) { p.tlsManager = tlsManager } // SetConfigListenerChan initializes the configFromListenerChan. func (p *Provider) SetConfigListenerChan(configFromListenerChan chan dynamic.Configuration) { p.configFromListenerChan = configFromListenerChan } // ListenConfiguration sets a new Configuration into the configFromListenerChan. func (p *Provider) ListenConfiguration(config dynamic.Configuration) { p.configFromListenerChan <- config } // Init for compatibility reason the BaseProvider implements an empty Init. func (p *Provider) Init() error { ctx := log.With(context.Background(), log.Str(log.ProviderName, p.ResolverName+".acme")) logger := log.FromContext(ctx) if len(p.Configuration.Storage) == 0 { return errors.New("unable to initialize ACME provider with no storage location for the certificates") } var err error p.account, err = p.Store.GetAccount(p.ResolverName) if err != nil { return fmt.Errorf("unable to get ACME account: %w", err) } // Reset Account if caServer changed, thus registration URI can be updated if p.account != nil && p.account.Registration != nil && !isAccountMatchingCaServer(ctx, p.account.Registration.URI, p.CAServer) { logger.Info("Account URI does not match the current CAServer. The account will be reset.") p.account = nil } p.certificates, err = p.Store.GetCertificates(p.ResolverName) if err != nil { return fmt.Errorf("unable to get ACME certificates : %w", err) } // Init the currently resolved domain map p.resolvingDomains = make(map[string]struct{}) return nil } func isAccountMatchingCaServer(ctx context.Context, accountURI, serverURI string) bool { logger := log.FromContext(ctx) aru, err := url.Parse(accountURI) if err != nil { logger.Infof("Unable to parse account.Registration URL: %v", err) return false } cau, err := url.Parse(serverURI) if err != nil { logger.Infof("Unable to parse CAServer URL: %v", err) return false } return cau.Hostname() == aru.Hostname() } // Provide allows the file provider to provide configurations to traefik // using the given Configuration channel. func (p *Provider) Provide(configurationChan chan<- dynamic.Message, pool *safe.Pool) error { ctx := log.With(context.Background(), log.Str(log.ProviderName, p.ResolverName+".acme")) p.pool = pool p.watchCertificate(ctx) p.watchNewDomains(ctx) p.configurationChan = configurationChan p.refreshCertificates() p.renewCertificates(ctx) ticker := time.NewTicker(24 * time.Hour) pool.GoCtx(func(ctxPool context.Context) { for { select { case <-ticker.C: p.renewCertificates(ctx) case <-ctxPool.Done(): ticker.Stop() return } } }) return nil } func (p *Provider) getClient() (*lego.Client, error) { p.clientMutex.Lock() defer p.clientMutex.Unlock() ctx := log.With(context.Background(), log.Str(log.ProviderName, p.ResolverName+".acme")) logger := log.FromContext(ctx) if p.client != nil { return p.client, nil } account, err := p.initAccount(ctx) if err != nil { return nil, err } logger.Debug("Building ACME client...") caServer := lego.LEDirectoryProduction if len(p.CAServer) > 0 { caServer = p.CAServer } logger.Debug(caServer) config := lego.NewConfig(account) config.CADirURL = caServer config.Certificate.KeyType = account.KeyType config.UserAgent = fmt.Sprintf("containous-traefik/%s", version.Version) client, err := lego.NewClient(config) if err != nil { return nil, err } // New users will need to register; be sure to save it if account.GetRegistration() == nil { logger.Info("Register...") reg, errR := client.Registration.Register(registration.RegisterOptions{TermsOfServiceAgreed: true}) if errR != nil { return nil, errR } account.Registration = reg } // Save the account once before all the certificates generation/storing // No certificate can be generated if account is not initialized err = p.Store.SaveAccount(p.ResolverName, account) if err != nil { return nil, err } if (p.DNSChallenge == nil || len(p.DNSChallenge.Provider) == 0) && (p.HTTPChallenge == nil || len(p.HTTPChallenge.EntryPoint) == 0) && p.TLSChallenge == nil { return nil, errors.New("ACME challenge not specified, please select TLS or HTTP or DNS Challenge") } if p.DNSChallenge != nil && len(p.DNSChallenge.Provider) > 0 { logger.Debugf("Using DNS Challenge provider: %s", p.DNSChallenge.Provider) var provider challenge.Provider provider, err = dns.NewDNSChallengeProviderByName(p.DNSChallenge.Provider) if err != nil { return nil, err } err = client.Challenge.SetDNS01Provider(provider, dns01.CondOption(len(p.DNSChallenge.Resolvers) > 0, dns01.AddRecursiveNameservers(p.DNSChallenge.Resolvers)), dns01.WrapPreCheck(func(domain, fqdn, value string, check dns01.PreCheckFunc) (bool, error) { if p.DNSChallenge.DisablePropagationCheck { return true, nil } if p.DNSChallenge.DelayBeforeCheck > 0 { logger.Debugf("Delaying %d rather than validating DNS propagation now.", p.DNSChallenge.DelayBeforeCheck) time.Sleep(time.Duration(p.DNSChallenge.DelayBeforeCheck)) } return check(fqdn, value) }), ) if err != nil { return nil, err } } if p.HTTPChallenge != nil && len(p.HTTPChallenge.EntryPoint) > 0 { logger.Debug("Using HTTP Challenge provider.") err = client.Challenge.SetHTTP01Provider(&challengeHTTP{Store: p.ChallengeStore}) if err != nil { return nil, err } } if p.TLSChallenge != nil { logger.Debug("Using TLS Challenge provider.") err = client.Challenge.SetTLSALPN01Provider(&challengeTLSALPN{Store: p.ChallengeStore}) if err != nil { return nil, err } } p.client = client return p.client, nil } func (p *Provider) initAccount(ctx context.Context) (*Account, error) { if p.account == nil || len(p.account.Email) == 0 { var err error p.account, err = NewAccount(ctx, p.Email, p.KeyType) if err != nil { return nil, err } } // Set the KeyType if not already defined in the account if len(p.account.KeyType) == 0 { p.account.KeyType = GetKeyType(ctx, p.KeyType) } return p.account, nil } func (p *Provider) resolveDomains(ctx context.Context, domains []string, tlsStore string) { if len(domains) == 0 { log.FromContext(ctx).Debug("No domain parsed in provider ACME") return } log.FromContext(ctx).Debugf("Try to challenge certificate for domain %v found in HostSNI rule", domains) var domain types.Domain if len(domains) > 0 { domain = types.Domain{Main: domains[0]} if len(domains) > 1 { domain.SANs = domains[1:] } safe.Go(func() { if _, err := p.resolveCertificate(ctx, domain, tlsStore); err != nil { log.FromContext(ctx).Errorf("Unable to obtain ACME certificate for domains %q: %v", strings.Join(domains, ","), err) } }) } } func (p *Provider) watchNewDomains(ctx context.Context) { p.pool.GoCtx(func(ctxPool context.Context) { for { select { case config := <-p.configFromListenerChan: if config.TCP != nil { for routerName, route := range config.TCP.Routers { if route.TLS == nil || route.TLS.CertResolver != p.ResolverName { continue } ctxRouter := log.With(ctx, log.Str(log.RouterName, routerName), log.Str(log.Rule, route.Rule)) logger := log.FromContext(ctxRouter) tlsStore := "default" if len(route.TLS.Domains) > 0 { for _, domain := range route.TLS.Domains { if domain.Main != dns01.UnFqdn(domain.Main) { logger.Warnf("FQDN detected, please remove the trailing dot: %s", domain.Main) } for _, san := range domain.SANs { if san != dns01.UnFqdn(san) { logger.Warnf("FQDN detected, please remove the trailing dot: %s", san) } } } domains := deleteUnnecessaryDomains(ctxRouter, route.TLS.Domains) for i := 0; i < len(domains); i++ { domain := domains[i] safe.Go(func() { if _, err := p.resolveCertificate(ctx, domain, tlsStore); err != nil { log.WithoutContext().WithField(log.ProviderName, p.ResolverName+".acme"). Errorf("Unable to obtain ACME certificate for domains %q : %v", strings.Join(domain.ToStrArray(), ","), err) } }) } } else { domains, err := rules.ParseHostSNI(route.Rule) if err != nil { logger.Errorf("Error parsing domains in provider ACME: %v", err) continue } p.resolveDomains(ctxRouter, domains, tlsStore) } } } for routerName, route := range config.HTTP.Routers { if route.TLS == nil || route.TLS.CertResolver != p.ResolverName { continue } ctxRouter := log.With(ctx, log.Str(log.RouterName, routerName), log.Str(log.Rule, route.Rule)) tlsStore := "default" if len(route.TLS.Domains) > 0 { domains := deleteUnnecessaryDomains(ctxRouter, route.TLS.Domains) for i := 0; i < len(domains); i++ { domain := domains[i] safe.Go(func() { if _, err := p.resolveCertificate(ctx, domain, tlsStore); err != nil { log.WithoutContext().WithField(log.ProviderName, p.ResolverName+".acme"). Errorf("Unable to obtain ACME certificate for domains %q : %v", strings.Join(domain.ToStrArray(), ","), err) } }) } } else { domains, err := rules.ParseDomains(route.Rule) if err != nil { log.FromContext(ctxRouter).Errorf("Error parsing domains in provider ACME: %v", err) continue } p.resolveDomains(ctxRouter, domains, tlsStore) } } case <-ctxPool.Done(): return } } }) } func (p *Provider) resolveCertificate(ctx context.Context, domain types.Domain, tlsStore string) (*certificate.Resource, error) { domains, err := p.getValidDomains(ctx, domain) if err != nil { return nil, err } // Check if provided certificates are not already in progress and lock them if needed uncheckedDomains := p.getUncheckedDomains(ctx, domains, tlsStore) if len(uncheckedDomains) == 0 { return nil, nil } defer p.removeResolvingDomains(uncheckedDomains) logger := log.FromContext(ctx) logger.Debugf("Loading ACME certificates %+v...", uncheckedDomains) client, err := p.getClient() if err != nil { return nil, fmt.Errorf("cannot get ACME client %w", err) } request := certificate.ObtainRequest{ Domains: domains, Bundle: true, MustStaple: oscpMustStaple, } cert, err := client.Certificate.Obtain(request) if err != nil { return nil, fmt.Errorf("unable to generate a certificate for the domains %v: %w", uncheckedDomains, err) } if cert == nil { return nil, fmt.Errorf("domains %v do not generate a certificate", uncheckedDomains) } if len(cert.Certificate) == 0 || len(cert.PrivateKey) == 0 { return nil, fmt.Errorf("domains %v generate certificate with no value: %v", uncheckedDomains, cert) } logger.Debugf("Certificates obtained for domains %+v", uncheckedDomains) if len(uncheckedDomains) > 1 { domain = types.Domain{Main: uncheckedDomains[0], SANs: uncheckedDomains[1:]} } else { domain = types.Domain{Main: uncheckedDomains[0]} } p.addCertificateForDomain(domain, cert.Certificate, cert.PrivateKey, tlsStore) return cert, nil } func (p *Provider) removeResolvingDomains(resolvingDomains []string) { p.resolvingDomainsMutex.Lock() defer p.resolvingDomainsMutex.Unlock() for _, domain := range resolvingDomains { delete(p.resolvingDomains, domain) } } func (p *Provider) addCertificateForDomain(domain types.Domain, certificate, key []byte, tlsStore string) { p.certsChan <- &CertAndStore{Certificate: Certificate{Certificate: certificate, Key: key, Domain: domain}, Store: tlsStore} } // deleteUnnecessaryDomains deletes from the configuration : // - Duplicated domains // - Domains which are checked by wildcard domain. func deleteUnnecessaryDomains(ctx context.Context, domains []types.Domain) []types.Domain { var newDomains []types.Domain logger := log.FromContext(ctx) for idxDomainToCheck, domainToCheck := range domains { keepDomain := true for idxDomain, domain := range domains { if idxDomainToCheck == idxDomain { continue } if reflect.DeepEqual(domain, domainToCheck) { if idxDomainToCheck > idxDomain { logger.Warnf("The domain %v is duplicated in the configuration but will be process by ACME provider only once.", domainToCheck) keepDomain = false } break } // Check if CN or SANS to check already exists // or can not be checked by a wildcard var newDomainsToCheck []string for _, domainProcessed := range domainToCheck.ToStrArray() { if idxDomain < idxDomainToCheck && isDomainAlreadyChecked(domainProcessed, domain.ToStrArray()) { // The domain is duplicated in a CN logger.Warnf("Domain %q is duplicated in the configuration or validated by the domain %v. It will be processed once.", domainProcessed, domain) continue } else if domain.Main != domainProcessed && strings.HasPrefix(domain.Main, "*") && isDomainAlreadyChecked(domainProcessed, []string{domain.Main}) { // Check if a wildcard can validate the domain logger.Warnf("Domain %q will not be processed by ACME provider because it is validated by the wildcard %q", domainProcessed, domain.Main) continue } newDomainsToCheck = append(newDomainsToCheck, domainProcessed) } // Delete the domain if both Main and SANs can be validated by the wildcard domain // otherwise keep the unchecked values if newDomainsToCheck == nil { keepDomain = false break } domainToCheck.Set(newDomainsToCheck) } if keepDomain { newDomains = append(newDomains, domainToCheck) } } return newDomains } func (p *Provider) watchCertificate(ctx context.Context) { p.certsChan = make(chan *CertAndStore) p.pool.GoCtx(func(ctxPool context.Context) { for { select { case cert := <-p.certsChan: certUpdated := false for _, domainsCertificate := range p.certificates { if reflect.DeepEqual(cert.Domain, domainsCertificate.Certificate.Domain) { domainsCertificate.Certificate = cert.Certificate certUpdated = true break } } if !certUpdated { p.certificates = append(p.certificates, cert) } err := p.saveCertificates() if err != nil { log.FromContext(ctx).Error(err) } case <-ctxPool.Done(): return } } }) } func (p *Provider) saveCertificates() error { err := p.Store.SaveCertificates(p.ResolverName, p.certificates) p.refreshCertificates() return err } func (p *Provider) refreshCertificates() { conf := dynamic.Message{ ProviderName: p.ResolverName + ".acme", Configuration: &dynamic.Configuration{ HTTP: &dynamic.HTTPConfiguration{ Routers: map[string]*dynamic.Router{}, Middlewares: map[string]*dynamic.Middleware{}, Services: map[string]*dynamic.Service{}, }, TLS: &dynamic.TLSConfiguration{}, }, } for _, cert := range p.certificates { certConf := &traefiktls.CertAndStores{ Certificate: traefiktls.Certificate{ CertFile: traefiktls.FileOrContent(cert.Certificate.Certificate), KeyFile: traefiktls.FileOrContent(cert.Key), }, Stores: []string{cert.Store}, } conf.Configuration.TLS.Certificates = append(conf.Configuration.TLS.Certificates, certConf) } p.configurationChan <- conf } func (p *Provider) renewCertificates(ctx context.Context) { logger := log.FromContext(ctx) logger.Info("Testing certificate renew...") for _, cert := range p.certificates { crt, err := getX509Certificate(ctx, &cert.Certificate) // If there's an error, we assume the cert is broken, and needs update // <= 30 days left, renew certificate if err != nil || crt == nil || crt.NotAfter.Before(time.Now().Add(24*30*time.Hour)) { client, err := p.getClient() if err != nil { logger.Infof("Error renewing certificate from LE : %+v, %v", cert.Domain, err) continue } logger.Infof("Renewing certificate from LE : %+v", cert.Domain) renewedCert, err := client.Certificate.Renew(certificate.Resource{ Domain: cert.Domain.Main, PrivateKey: cert.Key, Certificate: cert.Certificate.Certificate, }, true, oscpMustStaple, p.PreferredChain) if err != nil { logger.Errorf("Error renewing certificate from LE: %v, %v", cert.Domain, err) continue } if len(renewedCert.Certificate) == 0 || len(renewedCert.PrivateKey) == 0 { logger.Errorf("domains %v renew certificate with no value: %v", cert.Domain.ToStrArray(), cert) continue } p.addCertificateForDomain(cert.Domain, renewedCert.Certificate, renewedCert.PrivateKey, cert.Store) } } } // Get provided certificate which check a domains list (Main and SANs) // from static and dynamic provided certificates. func (p *Provider) getUncheckedDomains(ctx context.Context, domainsToCheck []string, tlsStore string) []string { p.resolvingDomainsMutex.Lock() defer p.resolvingDomainsMutex.Unlock() log.FromContext(ctx).Debugf("Looking for provided certificate(s) to validate %q...", domainsToCheck) allDomains := p.tlsManager.GetStore(tlsStore).GetAllDomains() // Get ACME certificates for _, cert := range p.certificates { allDomains = append(allDomains, strings.Join(cert.Domain.ToStrArray(), ",")) } // Get currently resolved domains for domain := range p.resolvingDomains { allDomains = append(allDomains, domain) } uncheckedDomains := searchUncheckedDomains(ctx, domainsToCheck, allDomains) // Lock domains that will be resolved by this routine for _, domain := range uncheckedDomains { p.resolvingDomains[domain] = struct{}{} } return uncheckedDomains } func searchUncheckedDomains(ctx context.Context, domainsToCheck, existentDomains []string) []string { var uncheckedDomains []string for _, domainToCheck := range domainsToCheck { if !isDomainAlreadyChecked(domainToCheck, existentDomains) { uncheckedDomains = append(uncheckedDomains, domainToCheck) } } logger := log.FromContext(ctx) if len(uncheckedDomains) == 0 { logger.Debugf("No ACME certificate generation required for domains %q.", domainsToCheck) } else { logger.Debugf("Domains %q need ACME certificates generation for domains %q.", domainsToCheck, strings.Join(uncheckedDomains, ",")) } return uncheckedDomains } func getX509Certificate(ctx context.Context, cert *Certificate) (*x509.Certificate, error) { logger := log.FromContext(ctx) tlsCert, err := tls.X509KeyPair(cert.Certificate, cert.Key) if err != nil { logger.Errorf("Failed to load TLS key pair from ACME certificate for domain %q (SAN : %q), certificate will be renewed : %v", cert.Domain.Main, strings.Join(cert.Domain.SANs, ","), err) return nil, err } crt := tlsCert.Leaf if crt == nil { crt, err = x509.ParseCertificate(tlsCert.Certificate[0]) if err != nil { logger.Errorf("Failed to parse TLS key pair from ACME certificate for domain %q (SAN : %q), certificate will be renewed : %v", cert.Domain.Main, strings.Join(cert.Domain.SANs, ","), err) } } return crt, err } // getValidDomains checks if given domain is allowed to generate a ACME certificate and return it. func (p *Provider) getValidDomains(ctx context.Context, domain types.Domain) ([]string, error) { domains := domain.ToStrArray() if len(domains) == 0 { return nil, errors.New("unable to generate a certificate in ACME provider when no domain is given") } if strings.HasPrefix(domain.Main, "*") { if p.DNSChallenge == nil { return nil, fmt.Errorf("unable to generate a wildcard certificate in ACME provider for domain %q : ACME needs a DNSChallenge", strings.Join(domains, ",")) } if strings.HasPrefix(domain.Main, "*.*") { return nil, fmt.Errorf("unable to generate a wildcard certificate in ACME provider for domain %q : ACME does not allow '*.*' wildcard domain", strings.Join(domains, ",")) } } var cleanDomains []string for _, domain := range domains { canonicalDomain := types.CanonicalDomain(domain) cleanDomain := dns01.UnFqdn(canonicalDomain) if canonicalDomain != cleanDomain { log.FromContext(ctx).Warnf("FQDN detected, please remove the trailing dot: %s", canonicalDomain) } cleanDomains = append(cleanDomains, cleanDomain) } return cleanDomains, nil } func isDomainAlreadyChecked(domainToCheck string, existentDomains []string) bool { for _, certDomains := range existentDomains { for _, certDomain := range strings.Split(certDomains, ",") { if types.MatchDomain(domainToCheck, certDomain) { return true } } } return false }