Refactor TLS

common/tls/std_server.go

@@ -0,0 +1,224 @@
+package tls
+
+import (
+	"context"
+	"crypto/tls"
+	"net"
+	"os"
+
+	"github.com/sagernet/sing-box/adapter"
+	"github.com/sagernet/sing-box/log"
+	"github.com/sagernet/sing-box/option"
+	"github.com/sagernet/sing/common"
+	E "github.com/sagernet/sing/common/exceptions"
+
+	"github.com/fsnotify/fsnotify"
+)
+
+type STDServerConfig struct {
+	config          *tls.Config
+	logger          log.Logger
+	acmeService     adapter.Service
+	certificate     []byte
+	key             []byte
+	certificatePath string
+	keyPath         string
+	watcher         *fsnotify.Watcher
+}
+
+func NewServer(ctx context.Context, logger log.Logger, options option.InboundTLSOptions) (ServerConfig, error) {
+	if !options.Enabled {
+		return nil, nil
+	}
+	var tlsConfig *tls.Config
+	var acmeService adapter.Service
+	var err error
+	if options.ACME != nil && len(options.ACME.Domain) > 0 {
+		tlsConfig, acmeService, err = startACME(ctx, common.PtrValueOrDefault(options.ACME))
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		tlsConfig = &tls.Config{}
+	}
+	if options.ServerName != "" {
+		tlsConfig.ServerName = options.ServerName
+	}
+	if len(options.ALPN) > 0 {
+		tlsConfig.NextProtos = append(tlsConfig.NextProtos, options.ALPN...)
+	}
+	if options.MinVersion != "" {
+		minVersion, err := ParseTLSVersion(options.MinVersion)
+		if err != nil {
+			return nil, E.Cause(err, "parse min_version")
+		}
+		tlsConfig.MinVersion = minVersion
+	}
+	if options.MaxVersion != "" {
+		maxVersion, err := ParseTLSVersion(options.MaxVersion)
+		if err != nil {
+			return nil, E.Cause(err, "parse max_version")
+		}
+		tlsConfig.MaxVersion = maxVersion
+	}
+	if options.CipherSuites != nil {
+	find:
+		for _, cipherSuite := range options.CipherSuites {
+			for _, tlsCipherSuite := range tls.CipherSuites() {
+				if cipherSuite == tlsCipherSuite.Name {
+					tlsConfig.CipherSuites = append(tlsConfig.CipherSuites, tlsCipherSuite.ID)
+					continue find
+				}
+			}
+			return nil, E.New("unknown cipher_suite: ", cipherSuite)
+		}
+	}
+	var certificate []byte
+	var key []byte
+	if acmeService == nil {
+		if options.Certificate != "" {
+			certificate = []byte(options.Certificate)
+		} else if options.CertificatePath != "" {
+			content, err := os.ReadFile(options.CertificatePath)
+			if err != nil {
+				return nil, E.Cause(err, "read certificate")
+			}
+			certificate = content
+		}
+		if options.Key != "" {
+			key = []byte(options.Key)
+		} else if options.KeyPath != "" {
+			content, err := os.ReadFile(options.KeyPath)
+			if err != nil {
+				return nil, E.Cause(err, "read key")
+			}
+			key = content
+		}
+		if certificate == nil {
+			return nil, E.New("missing certificate")
+		}
+		if key == nil {
+			return nil, E.New("missing key")
+		}
+		keyPair, err := tls.X509KeyPair(certificate, key)
+		if err != nil {
+			return nil, E.Cause(err, "parse x509 key pair")
+		}
+		tlsConfig.Certificates = []tls.Certificate{keyPair}
+	}
+	return &STDServerConfig{
+		config:          tlsConfig,
+		logger:          logger,
+		acmeService:     acmeService,
+		certificate:     certificate,
+		key:             key,
+		certificatePath: options.CertificatePath,
+		keyPath:         options.KeyPath,
+	}, nil
+}
+
+func (c *STDServerConfig) Config() (*STDConfig, error) {
+	return c.config, nil
+}
+
+func (c *STDServerConfig) Client(conn net.Conn) Conn {
+	return tls.Client(conn, c.config)
+}
+
+func (c *STDServerConfig) Server(conn net.Conn) Conn {
+	return tls.Server(conn, c.config)
+}
+
+func (c *STDServerConfig) Start() error {
+	if c.acmeService != nil {
+		return c.acmeService.Start()
+	} else {
+		if c.certificatePath == "" && c.keyPath == "" {
+			return nil
+		}
+		err := c.startWatcher()
+		if err != nil {
+			c.logger.Warn("create fsnotify watcher: ", err)
+		}
+		return nil
+	}
+}
+
+func (c *STDServerConfig) startWatcher() error {
+	watcher, err := fsnotify.NewWatcher()
+	if err != nil {
+		return err
+	}
+	if c.certificatePath != "" {
+		err = watcher.Add(c.certificatePath)
+		if err != nil {
+			return err
+		}
+	}
+	if c.keyPath != "" {
+		err = watcher.Add(c.keyPath)
+		if err != nil {
+			return err
+		}
+	}
+	c.watcher = watcher
+	go c.loopUpdate()
+	return nil
+}
+
+func (c *STDServerConfig) loopUpdate() {
+	for {
+		select {
+		case event, ok := <-c.watcher.Events:
+			if !ok {
+				return
+			}
+			if event.Op&fsnotify.Write != fsnotify.Write {
+				continue
+			}
+			err := c.reloadKeyPair()
+			if err != nil {
+				c.logger.Error(E.Cause(err, "reload TLS key pair"))
+			}
+		case err, ok := <-c.watcher.Errors:
+			if !ok {
+				return
+			}
+			c.logger.Error(E.Cause(err, "fsnotify error"))
+		}
+	}
+}
+
+func (c *STDServerConfig) reloadKeyPair() error {
+	if c.certificatePath != "" {
+		certificate, err := os.ReadFile(c.certificatePath)
+		if err != nil {
+			return E.Cause(err, "reload certificate from ", c.certificatePath)
+		}
+		c.certificate = certificate
+	}
+	if c.keyPath != "" {
+		key, err := os.ReadFile(c.keyPath)
+		if err != nil {
+			return E.Cause(err, "reload key from ", c.keyPath)
+		}
+		c.key = key
+	}
+	keyPair, err := tls.X509KeyPair(c.certificate, c.key)
+	if err != nil {
+		return E.Cause(err, "reload key pair")
+	}
+	c.config.Certificates = []tls.Certificate{keyPair}
+	c.logger.Info("reloaded TLS certificate")
+	return nil
+}
+
+func (c *STDServerConfig) Close() error {
+	if c.acmeService != nil {
+		return c.acmeService.Close()
+	}
+	if c.watcher != nil {
+		return c.watcher.Close()
+	}
+	return nil
+}