caddytls: Regularly reload static certificates

Author: pascalgn

modules/caddytls/storageloader.go

@@ -72,17 +72,16 @@ func (sl *StorageLoader) Provision(ctx caddy.Context) error {
 	return nil
 }
 
-// LoadCertificates returns the certificates to be loaded by sl.
-func (sl StorageLoader) LoadCertificates() ([]Certificate, error) {
+func (sl StorageLoader) Initialize(updateCertificates func(add []Certificate, remove []string) error) error {
 	certs := make([]Certificate, 0, len(sl.Pairs))
 	for _, pair := range sl.Pairs {
 		certData, err := sl.storage.Load(sl.ctx, pair.Certificate)
 		if err != nil {
-			return nil, err
+			return err
 		}
 		keyData, err := sl.storage.Load(sl.ctx, pair.Key)
 		if err != nil {
-			return nil, err
+			return err
 		}
 
 		var cert tls.Certificate
@@ -94,21 +93,21 @@ func (sl StorageLoader) LoadCertificates() ([]Certificate, error) {
 			// if the start of the key file looks like an encrypted private key,
 			// reject it with a helpful error message
 			if strings.Contains(string(keyData[:40]), "ENCRYPTED") {
-				return nil, fmt.Errorf("encrypted private keys are not supported; please decrypt the key first")
+				return fmt.Errorf("encrypted private keys are not supported; please decrypt the key first")
 			}
 
 			cert, err = tls.X509KeyPair(certData, keyData)
 
 		default:
-			return nil, fmt.Errorf("unrecognized certificate/key encoding format: %s", pair.Format)
+			return fmt.Errorf("unrecognized certificate/key encoding format: %s", pair.Format)
 		}
 		if err != nil {
-			return nil, err
+			return err
 		}
 
 		certs = append(certs, Certificate{Certificate: cert, Tags: pair.Tags})
 	}
-	return certs, nil
+	return updateCertificates(certs, []string{})
 }
 
 // Interface guard

modules/caddytls/tls.go

@@ -122,15 +122,13 @@ type TLS struct {
 	DNSRaw json.RawMessage `json:"dns,omitempty" caddy:"namespace=dns.providers inline_key=name"`
 	dns    any             // technically, it should be any/all of the libdns interfaces (RecordSetter, RecordAppender, etc.)
 
-	magic                *certmagic.Config
-	certificateLoaders   []CertificateLoader
-	unmanagedCertsTicker *time.Ticker
-	automateNames        []string
-	ctx                  caddy.Context
-	storageCleanTicker   *time.Ticker
-	storageCleanStop     chan struct{}
-	logger               *zap.Logger
-	events               *caddyevents.App
+	certificateLoaders []CertificateLoader
+	automateNames      []string
+	ctx                caddy.Context
+	storageCleanTicker *time.Ticker
+	storageCleanStop   chan struct{}
+	logger             *zap.Logger
+	events             *caddyevents.App
 
 	serverNames   map[string]struct{}
 	serverNamesMu *sync.Mutex
@@ -240,7 +238,7 @@ func (t *TLS) Provision(ctx caddy.Context) error {
 	// certificates have been manually loaded, and also so that
 	// commands like validate can be a better test
 	certCacheMu.RLock()
-	t.magic = certmagic.New(certCache, certmagic.Config{
+	magic := certmagic.New(certCache, certmagic.Config{
 		Storage: ctx.Storage(),
 		Logger:  t.logger,
 		OnEvent: t.onEvent,
@@ -251,13 +249,13 @@ func (t *TLS) Provision(ctx caddy.Context) error {
 	})
 	certCacheMu.RUnlock()
 
-	unmanaged, err := t.loadUnmanagedCertificates(ctx)
-	if err != nil {
-		return err
-	}
-
-	if unmanaged > 0 {
-		t.regularlyReloadUnmanagedCertificates()
+	for _, loader := range t.certificateLoaders {
+		err := loader.Initialize(func(add []Certificate, remove []string) error {
+			return t.updateCertificates(ctx, magic, add, remove)
+		})
+		if err != nil {
+			return fmt.Errorf("loading certificates: %v", err)
+		}
 	}
 
 	// on-demand permission module
@@ -718,58 +716,17 @@ func (t *TLS) HasCertificateForSubject(subject string) bool {
 	return false
 }
 
-func (t *TLS) loadUnmanagedCertificates(ctx caddy.Context) (int, error) {
-	cached := 0
-	for _, loader := range t.certificateLoaders {
-		certs, err := loader.LoadCertificates()
-		if err != nil {
-			return 0, fmt.Errorf("loading certificates: %v", err)
-		}
-		for _, cert := range certs {
-			hash, err := t.magic.CacheUnmanagedTLSCertificate(ctx, cert.Certificate, cert.Tags)
-			if err != nil {
-				return 0, fmt.Errorf("caching unmanaged certificate: %v", err)
-			}
-			t.loaded[hash] = ""
-		}
-	}
-	return cached, nil
-}
-
-func (t *TLS) regularlyReloadUnmanagedCertificates() {
-	t.unmanagedCertsTicker = time.NewTicker(2 * time.Hour)
-	go func() {
-		defer func() {
-			if err := recover(); err != nil {
-				log.Printf("[PANIC] unmanaged certificates reloader: %v\n%s", err, debug.Stack())
-			}
-		}()
-		t.reloadUnmanagedCertificates()
-		for {
-			select {
-			case <-t.storageCleanStop:
-				return
-			case <-t.storageCleanTicker.C:
-				t.cleanStorageUnits()
-			}
-		}
-	}()
-}
-
-func (t *TLS) reloadUnmanagedCertificates() error {
-	for _, loader := range t.certificateLoaders {
-		certs, err := loader.LoadCertificates()
+func (t *TLS) updateCertificates(ctx caddy.Context, magic *certmagic.Config, add []Certificate, remove []string) error {
+	for _, cert := range add {
+		hash, err := magic.CacheUnmanagedTLSCertificate(ctx, cert.Certificate, cert.Tags)
 		if err != nil {
-			return fmt.Errorf("loading certificates: %v", err)
-		}
-		for _, cert := range certs {
-			hash, err := t.magic.CacheUnmanagedTLSCertificate(t.ctx, cert.Certificate, cert.Tags)
-			if err != nil {
-				return fmt.Errorf("caching unmanaged certificate: %v", err)
-			}
-			t.loaded[hash] = ""
+			return fmt.Errorf("caching unmanaged certificate: %v", err)
 		}
+		t.loaded[hash] = ""
 	}
+	certCacheMu.Lock()
+	certCache.Remove(remove)
+	certCacheMu.Unlock()
 	return nil
 }
 
@@ -878,7 +835,7 @@ func (t *TLS) onEvent(ctx context.Context, eventName string, data map[string]any
 // CertificateLoader is a type that can load certificates.
 // Certificates can optionally be associated with tags.
 type CertificateLoader interface {
-	LoadCertificates() ([]Certificate, error)
+	Initialize(updateCertificates func(add []Certificate, remove []string) error) error
 }
 
 // Certificate is a TLS certificate, optionally