tlsmanager: fix autocert autogeneration

As the getConfig() function would previously overwrite the
GetCertificateFunction of the tls config, the autocert manager would
never be used.

tls_manager.go

@@ -94,7 +94,7 @@ func NewTLSManager(cfg *TLSManagerCfg) *TLSManager {
 // getConfig returns a TLS configuration for the gRPC server and credentials
 // and a proxy destination for the REST reverse proxy.
 func (t *TLSManager) getConfig() ([]grpc.ServerOption, []grpc.DialOption,
-	func(net.Addr) (net.Listener, error), error) {
+	func(net.Addr) (net.Listener, error), func(), error) {
 
 	var (
 		keyBytes, certBytes []byte
@@ -108,19 +108,19 @@ func (t *TLSManager) getConfig() ([]grpc.ServerOption, []grpc.DialOption,
 			t.cfg.TLSCertPath, t.cfg.TLSKeyPath,
 		)
 		if err != nil {
-			return nil, nil, nil, err
+			return nil, nil, nil, nil, err
 		}
 	}
 
 	certData, _, err := cert.LoadCertFromBytes(certBytes, keyBytes)
 	if err != nil {
-		return nil, nil, nil, err
+		return nil, nil, nil, nil, err
 	}
 
 	if t.tlsReloader == nil {
 		tlsr, err := cert.NewTLSReloader(certBytes, keyBytes)
 		if err != nil {
-			return nil, nil, nil, err
+			return nil, nil, nil, nil, err
 		}
 		t.tlsReloader = tlsr
 	}
@@ -128,6 +128,10 @@ func (t *TLSManager) getConfig() ([]grpc.ServerOption, []grpc.DialOption,
 	tlsCfg := cert.TLSConfFromCert(certData)
 	tlsCfg.GetCertificate = t.tlsReloader.GetCertificateFunc()
 
+	// If Let's Encrypt is enabled, we need to set up the autocert manager
+	// and override the TLS config's GetCertificate function.
+	cleanUp := t.setUpLetsEncrypt(&certData, tlsCfg)
+
 	// If we're using the ephemeral certificate, we need to use the
 	// ephemeral cert path.
 	certPath := t.cfg.TLSCertPath
@@ -141,7 +145,7 @@ func (t *TLSManager) getConfig() ([]grpc.ServerOption, []grpc.DialOption,
 		certPath, "",
 	)
 	if err != nil {
-		return nil, nil, nil, err
+		return nil, nil, nil, nil, err
 	}
 
 	serverCreds := credentials.NewTLS(tlsCfg)
@@ -171,40 +175,39 @@ func (t *TLSManager) getConfig() ([]grpc.ServerOption, []grpc.DialOption,
 		return lncfg.TLSListenOnAddress(addr, tlsCfg)
 	}
 
-	return serverOpts, restDialOpts, restListen, nil
+	return serverOpts, restDialOpts, restListen, cleanUp, nil
 }
 
 // generateOrRenewCert generates a new TLS certificate if we're not using one
 // yet or renews it if it's outdated.
-func (t *TLSManager) generateOrRenewCert() (*tls.Config, func(), error) {
+func (t *TLSManager) generateOrRenewCert() (*tls.Config, error) {
 	// Generete a TLS pair if we don't have one yet.
 	var emptyKeyRing keychain.SecretKeyRing
 	err := t.generateCertPair(emptyKeyRing)
 	if err != nil {
-		return nil, nil, err
+		return nil, err
 	}
 
 	certData, parsedCert, err := cert.LoadCert(
 		t.cfg.TLSCertPath, t.cfg.TLSKeyPath,
 	)
 	if err != nil {
-		return nil, nil, err
+		return nil, err
 	}
 
 	// Check to see if the certificate needs to be renewed. If it does, we
 	// return the newly generated certificate data instead.
 	reloadedCertData, err := t.maintainCert(parsedCert)
 	if err != nil {
-		return nil, nil, err
+		return nil, err
 	}
 	if reloadedCertData != nil {
 		certData = *reloadedCertData
 	}
 
 	tlsCfg := cert.TLSConfFromCert(certData)
-	cleanUp := t.setUpLetsEncrypt(&certData, tlsCfg)
 
-	return tlsCfg, cleanUp, nil
+	return tlsCfg, nil
 }
 
 // generateCertPair creates and writes a TLS pair to disk if the pair
@@ -474,7 +477,6 @@ func (t *TLSManager) SetCertificateBeforeUnlock() ([]grpc.ServerOption,
 	[]grpc.DialOption, func(net.Addr) (net.Listener, error), func(),
 	error) {
 
-	var cleanUp func()
 	if t.cfg.TLSEncryptKey {
 		_, err := t.loadEphemeralCertificate()
 		if err != nil {
@@ -482,15 +484,14 @@ func (t *TLSManager) SetCertificateBeforeUnlock() ([]grpc.ServerOption,
 				"ephemeral certificate: %v", err)
 		}
 	} else {
-		_, cleanUpFunc, err := t.generateOrRenewCert()
+		_, err := t.generateOrRenewCert()
 		if err != nil {
 			return nil, nil, nil, nil, fmt.Errorf("unable to "+
 				"generate or renew TLS certificate: %v", err)
 		}
-		cleanUp = cleanUpFunc
 	}
 
-	serverOpts, restDialOpts, restListen, err := t.getConfig()
+	serverOpts, restDialOpts, restListen, cleanUp, err := t.getConfig()
 	if err != nil {
 		return nil, nil, nil, nil, fmt.Errorf("unable to load TLS "+
 			"credentials: %v", err)

tls_manager_test.go

@@ -53,9 +53,9 @@ func TestGenerateOrRenewCert(t *testing.T) {
 		TLSCertDuration: testTLSCertDuration,
 	}
 	tlsManager := NewTLSManager(cfg)
-	_, cleanUp, err := tlsManager.generateOrRenewCert()
+	_, err := tlsManager.generateOrRenewCert()
 	require.NoError(t, err)
-	_, _, _, err = tlsManager.getConfig()
+	_, _, _, cleanUp, err := tlsManager.getConfig()
 	require.NoError(t, err, "couldn't retrieve TLS config")
 	t.Cleanup(cleanUp)
 
@@ -86,7 +86,7 @@ func TestTLSManagerGenCert(t *testing.T) {
 	}
 	tlsManager := NewTLSManager(cfg)
 
-	_, _, err := tlsManager.generateOrRenewCert()
+	_, err := tlsManager.generateOrRenewCert()
 	require.NoError(t, err, "failed to generate new certificate")
 
 	// After this is run, a new certificate should be created and written