add sni handler

cmd/gost/main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"crypto/tls"
 	"flag"
 	"fmt"
 	"net/http"
@@ -8,6 +9,7 @@ import (
 	"os"
 	"runtime"
 
+	tls_util "github.com/go-gost/gost/pkg/common/util/tls"
 	"github.com/go-gost/gost/pkg/config"
 	"github.com/go-gost/gost/pkg/logger"
 )
@@ -64,6 +66,8 @@ func main() {
 
 	normConfig(cfg)
 
+	log = logFromConfig(cfg.Log)
+
 	if outputCfgFile != "" {
 		if err := cfg.WriteFile(outputCfgFile); err != nil {
 			log.Fatal(err)
@@ -71,8 +75,6 @@ func main() {
 		os.Exit(0)
 	}
 
-	log = logFromConfig(cfg.Log)
-
 	if cfg.Profiling != nil && cfg.Profiling.Enabled {
 		go func() {
 			addr := cfg.Profiling.Addr
@@ -83,6 +85,31 @@ func main() {
 			log.Fatal(http.ListenAndServe(addr, nil))
 		}()
 	}
+
+	tlsCfg := cfg.TLS
+	if tlsCfg == nil {
+		tlsCfg = &config.TLSConfig{
+			Cert: "cert.pem",
+			Key:  "key.pem",
+			CA:   "ca.crt",
+		}
+	}
+	tlsConfig, err := tls_util.LoadTLSConfig(tlsCfg.Cert, tlsCfg.Key, tlsCfg.CA)
+	if err != nil {
+		// generate random self-signed certificate.
+		cert, err := tls_util.GenCertificate()
+		if err != nil {
+			log.Fatal(err)
+		}
+		tlsConfig = &tls.Config{
+			Certificates: []tls.Certificate{cert},
+		}
+		log.Warn("load TLS certificate files failed, use random generated certificate")
+	} else {
+		log.Debug("load TLS certificate files OK")
+	}
+	tls_util.DefaultConfig = tlsConfig
+
 	services := buildService(cfg)
 	for _, svc := range services {
 		go svc.Run()

cmd/gost/out.yml

@@ -1,40 +1,27 @@
+log:
+  level: debug
 services:
 - name: service-0
-  url: ss://abc:123@:18338/:18338
+  url: udp://:10053/192.168.8.8:53,192.168.8.1:53
-  addr: :18338
+  addr: :10053
   chain: chain-0
   listener:
-    type: tcp
+    type: udp
-    metadata:
-      users:
-      - abc:123
   handler:
-    type: tcp
+    type: udp
-    metadata:
-      users:
-      - abc:123
   forwarder:
     targets:
-    - :18338
+    - 192.168.8.8:53
+    - 192.168.8.1:53
 chains:
 - name: chain-0
   hops:
   - name: hop-0
     nodes:
     - name: node-0
-      url: socks://abc:123@:11080?type=abc&key=value
+      url: relay://:8420
-      addr: :11080
+      addr: :8420
       dialer:
         type: tcp
-        metadata:
-          key: value
-          type: abc
-          user:
-          - abc:123
       connector:
-        type: socks
+        type: relay
-        metadata:
-          key: value
-          type: abc
-          user:
-          - abc:123

cmd/gost/register.go

@@ -20,6 +20,7 @@ import (
 	_ "github.com/go-gost/gost/pkg/handler/forward/remote"
 	_ "github.com/go-gost/gost/pkg/handler/http"
 	_ "github.com/go-gost/gost/pkg/handler/relay"
+	_ "github.com/go-gost/gost/pkg/handler/sni"
 	_ "github.com/go-gost/gost/pkg/handler/socks/v4"
 	_ "github.com/go-gost/gost/pkg/handler/socks/v5"
 	_ "github.com/go-gost/gost/pkg/handler/ss"

go.mod

@@ -9,6 +9,7 @@ require (
 	github.com/go-gost/gosocks4 v0.0.1
 	github.com/go-gost/gosocks5 v0.3.1-0.20211109033403-d894d75b7f09
 	github.com/go-gost/relay v0.1.1-0.20211123134818-8ef7fd81ffd7
+	github.com/go-gost/tls-dissector v0.0.2-0.20211125135007-2b5d5bd9c07e
 	github.com/gobwas/glob v0.2.3
 	github.com/golang/snappy v0.0.3
 	github.com/google/gopacket v1.1.19 // indirect

go.sum

@@ -113,10 +113,12 @@ github.com/go-gost/gosocks4 v0.0.1 h1:+k1sec8HlELuQV7rWftIkmy8UijzUt2I6t+iMPlGB2
 github.com/go-gost/gosocks4 v0.0.1/go.mod h1:3B6L47HbU/qugDg4JnoFPHgJXE43Inz8Bah1QaN9qCc=
 github.com/go-gost/gosocks5 v0.3.1-0.20211109033403-d894d75b7f09 h1:A95M6UWcfZgOuJkQ7QLfG0Hs5peWIUSysCDNz4pfe04=
 github.com/go-gost/gosocks5 v0.3.1-0.20211109033403-d894d75b7f09/go.mod h1:1G6I7HP7VFVxveGkoK8mnprnJqSqJjdcASKsdUn4Pp4=
-github.com/go-gost/relay v0.1.1-0.20211122150329-54ee406ea49d h1:rzGVzkSvxuDZg8PoYmOR+tvcAg9Dr8whgV19kzuO4YA=
-github.com/go-gost/relay v0.1.1-0.20211122150329-54ee406ea49d/go.mod h1:lcX+23LCQ3khIeASBo+tJ/WbwXFO32/N5YN6ucuYTG8=
 github.com/go-gost/relay v0.1.1-0.20211123134818-8ef7fd81ffd7 h1:itaaJhQJ19kUXEB4Igb0EbY8m+1Py2AaNNSBds/9gk4=
 github.com/go-gost/relay v0.1.1-0.20211123134818-8ef7fd81ffd7/go.mod h1:lcX+23LCQ3khIeASBo+tJ/WbwXFO32/N5YN6ucuYTG8=
+github.com/go-gost/tls-dissector v0.0.1 h1:cySZTSa7o5aOg/bqZXVFzi3NMudsiLwkzArFoxjUWCY=
+github.com/go-gost/tls-dissector v0.0.1/go.mod h1:8CmRTbp7v4Ebd/lewu/Y/4dEJOP9ke6nwumyJ9WlOec=
+github.com/go-gost/tls-dissector v0.0.2-0.20211125135007-2b5d5bd9c07e h1:73NGqAs22ey3wJkIYVD/ACEoovuIuOlEzQTEoqrO5+U=
+github.com/go-gost/tls-dissector v0.0.2-0.20211125135007-2b5d5bd9c07e/go.mod h1:/9QfdewqmHdaE362Hv5nDaSWLx3pCmtD870d6GaquXs=
 github.com/go-task/slim-sprig v0.0.0-20210107165309-348f09dbbbc0 h1:p104kn46Q8WdvHunIJ9dAyjPVtrBPhSr3KT2yUst43I=
 github.com/go-task/slim-sprig v0.0.0-20210107165309-348f09dbbbc0/go.mod h1:fyg7847qk6SyHyPtNmDHnmrv/HOrqktSC+C9fM+CJOE=
 github.com/gobwas/glob v0.2.3 h1:A4xDbljILXROh+kObIiy5kIaPYD8e96x1tgBhUI5J+Y=

pkg/common/util/tls/tls.go

@@ -1,10 +1,21 @@
 package tls
 
 import (
+	"crypto/rand"
+	"crypto/rsa"
 	"crypto/tls"
 	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/pem"
 	"errors"
 	"io/ioutil"
+	"math/big"
+	"time"
+)
+
+var (
+	// DefaultConfig is a default TLS config for global use.
+	DefaultConfig *tls.Config
 )
 
 // LoadTLSConfig loads the certificate from cert & key files and optional client CA file.
@@ -38,3 +49,48 @@ func loadCA(caFile string) (cp *x509.CertPool, err error) {
 	}
 	return
 }
+
+func GenCertificate() (cert tls.Certificate, err error) {
+	rawCert, rawKey, err := generateKeyPair()
+	if err != nil {
+		return
+	}
+	return tls.X509KeyPair(rawCert, rawKey)
+}
+
+func generateKeyPair() (rawCert, rawKey []byte, err error) {
+	// Create private key and self-signed certificate
+	// Adapted from https://golang.org/src/crypto/tls/generate_cert.go
+
+	priv, err := rsa.GenerateKey(rand.Reader, 2048)
+	if err != nil {
+		return
+	}
+	validFor := time.Hour * 24 * 365 * 10 // ten years
+	notBefore := time.Now()
+	notAfter := notBefore.Add(validFor)
+	serialNumberLimit := new(big.Int).Lsh(big.NewInt(1), 128)
+	serialNumber, _ := rand.Int(rand.Reader, serialNumberLimit)
+	template := x509.Certificate{
+		SerialNumber: serialNumber,
+		Subject: pkix.Name{
+			Organization: []string{"gost"},
+			CommonName:   "gost.run",
+		},
+		NotBefore: notBefore,
+		NotAfter:  notAfter,
+
+		KeyUsage:              x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
+		ExtKeyUsage:           []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth},
+		BasicConstraintsValid: true,
+	}
+	derBytes, err := x509.CreateCertificate(rand.Reader, &template, &template, &priv.PublicKey, priv)
+	if err != nil {
+		return
+	}
+
+	rawCert = pem.EncodeToMemory(&pem.Block{Type: "CERTIFICATE", Bytes: derBytes})
+	rawKey = pem.EncodeToMemory(&pem.Block{Type: "RSA PRIVATE KEY", Bytes: x509.MarshalPKCS1PrivateKey(priv)})
+
+	return
+}

pkg/config/config.go

@@ -31,6 +31,12 @@ type ProfilingConfig struct {
 	Enabled bool
 }
 
+type TLSConfig struct {
+	Cert string
+	Key  string
+	CA   string
+}
+
 type SelectorConfig struct {
 	Strategy    string
 	MaxFails    int
@@ -59,12 +65,12 @@ type ForwarderConfig struct {
 
 type DialerConfig struct {
 	Type     string
-	Metadata map[string]interface{}
+	Metadata map[string]interface{} `yaml:",omitempty"`
 }
 
 type ConnectorConfig struct {
 	Type     string
-	Metadata map[string]interface{}
+	Metadata map[string]interface{} `yaml:",omitempty"`
 }
 
 type ServiceConfig struct {
@@ -102,6 +108,7 @@ type NodeConfig struct {
 type Config struct {
 	Log       *LogConfig       `yaml:",omitempty"`
 	Profiling *ProfilingConfig `yaml:",omitempty"`
+	TLS       *TLSConfig       `yaml:",omitempty"`
 	Services  []*ServiceConfig
 	Chains    []*ChainConfig  `yaml:",omitempty"`
 	Bypasses  []*BypassConfig `yaml:",omitempty"`

pkg/handler/auto/handler.go

@@ -102,16 +102,16 @@ func (h *autoHandler) Handle(ctx context.Context, conn net.Conn) {
 		return
 	}
 
-	cc := handler.NewBufferReaderConn(conn, br)
+	conn = handler.NewBufferReaderConn(conn, br)
 	switch b[0] {
 	case gosocks4.Ver4: // socks4
-		h.socks4Handler.Handle(ctx, cc)
+		h.socks4Handler.Handle(ctx, conn)
 	case gosocks5.Ver5: // socks5
-		h.socks5Handler.Handle(ctx, cc)
+		h.socks5Handler.Handle(ctx, conn)
 	case relay.Version1: // relay
-		h.relayHandler.Handle(ctx, cc)
+		h.relayHandler.Handle(ctx, conn)
 	default: // http
-		h.httpHandler.Handle(ctx, cc)
+		h.httpHandler.Handle(ctx, conn)
 	}
 
 }

pkg/handler/sni/handler.go

@@ -0,0 +1,183 @@
+package sni
+
+import (
+	"bufio"
+	"context"
+	"encoding/base64"
+	"encoding/binary"
+	"errors"
+	"hash/crc32"
+	"io"
+	"net"
+	"time"
+
+	"github.com/go-gost/gost/pkg/bypass"
+	"github.com/go-gost/gost/pkg/chain"
+	"github.com/go-gost/gost/pkg/handler"
+	http_handler "github.com/go-gost/gost/pkg/handler/http"
+	"github.com/go-gost/gost/pkg/logger"
+	md "github.com/go-gost/gost/pkg/metadata"
+	"github.com/go-gost/gost/pkg/registry"
+	dissector "github.com/go-gost/tls-dissector"
+)
+
+func init() {
+	registry.RegisterHandler("sni", NewHandler)
+}
+
+type sniHandler struct {
+	httpHandler handler.Handler
+	chain       *chain.Chain
+	bypass      bypass.Bypass
+	logger      logger.Logger
+	md          metadata
+}
+
+func NewHandler(opts ...handler.Option) handler.Handler {
+	options := &handler.Options{}
+	for _, opt := range opts {
+		opt(options)
+	}
+
+	log := options.Logger
+	if log == nil {
+		log = logger.Default()
+	}
+
+	h := &sniHandler{
+		bypass: options.Bypass,
+		logger: log,
+	}
+
+	v := append(opts,
+		handler.LoggerOption(log.WithFields(map[string]interface{}{"type": "http"})))
+	h.httpHandler = http_handler.NewHandler(v...)
+
+	return h
+}
+
+func (h *sniHandler) Init(md md.Metadata) (err error) {
+	if err = h.parseMetadata(md); err != nil {
+		return
+	}
+	if err = h.httpHandler.Init(md); err != nil {
+		return
+	}
+
+	return nil
+}
+
+// WithChain implements chain.Chainable interface
+func (h *sniHandler) WithChain(chain *chain.Chain) {
+	h.chain = chain
+}
+
+func (h *sniHandler) Handle(ctx context.Context, conn net.Conn) {
+	defer conn.Close()
+
+	start := time.Now()
+	h.logger = h.logger.WithFields(map[string]interface{}{
+		"remote": conn.RemoteAddr().String(),
+		"local":  conn.LocalAddr().String(),
+	})
+
+	h.logger.Infof("%s <> %s", conn.RemoteAddr(), conn.LocalAddr())
+	defer func() {
+		h.logger.WithFields(map[string]interface{}{
+			"duration": time.Since(start),
+		}).Infof("%s >< %s", conn.RemoteAddr(), conn.LocalAddr())
+	}()
+
+	br := bufio.NewReader(conn)
+	hdr, err := br.Peek(dissector.RecordHeaderLen)
+	if err != nil {
+		h.logger.Error(err)
+		return
+	}
+
+	conn = handler.NewBufferReaderConn(conn, br)
+
+	if hdr[0] != dissector.Handshake {
+		// We assume it is an HTTP request
+		h.httpHandler.Handle(ctx, conn)
+		return
+	}
+
+	host, err := h.decodeHost(conn)
+	if err != nil {
+		h.logger.Error(err)
+		return
+	}
+	target := net.JoinHostPort(host, "443")
+
+	h.logger = h.logger.WithFields(map[string]interface{}{
+		"dst": target,
+	})
+	h.logger.Infof("%s >> %s", conn.RemoteAddr(), target)
+
+	if h.bypass != nil && h.bypass.Contains(target) {
+		h.logger.Info("bypass: ", target)
+		return
+	}
+
+	r := (&chain.Router{}).
+		WithChain(h.chain).
+		WithRetry(h.md.retryCount).
+		WithLogger(h.logger)
+	cc, err := r.Dial(ctx, "tcp", target)
+	if err != nil {
+		return
+	}
+	defer cc.Close()
+
+	t := time.Now()
+	h.logger.Infof("%s <-> %s", conn.RemoteAddr(), target)
+	handler.Transport(conn, cc)
+	h.logger.
+		WithFields(map[string]interface{}{
+			"duration": time.Since(t),
+		}).
+		Infof("%s >-< %s", conn.RemoteAddr(), target)
+}
+
+func (h *sniHandler) decodeHost(r io.Reader) (host string, err error) {
+	record, err := dissector.ReadRecord(r)
+	if err != nil {
+		return
+	}
+	clientHello := &dissector.ClientHelloMsg{}
+	if err = clientHello.Decode(record.Opaque); err != nil {
+		return
+	}
+
+	for _, ext := range clientHello.Extensions {
+		if ext.Type() == 0xFFFE {
+			b, _ := ext.Encode()
+			return h.decodeServerName(string(b))
+		}
+
+		if ext.Type() == dissector.ExtServerName {
+			snExtension := ext.(*dissector.ServerNameExtension)
+			host = snExtension.Name
+		}
+	}
+	return
+}
+
+func (h *sniHandler) decodeServerName(s string) (string, error) {
+	b, err := base64.RawURLEncoding.DecodeString(s)
+	if err != nil {
+		return "", err
+	}
+	if len(b) < 4 {
+		return "", errors.New("invalid name")
+	}
+	v, err := base64.RawURLEncoding.DecodeString(string(b[4:]))
+	if err != nil {
+		return "", err
+	}
+	if crc32.ChecksumIEEE(v) != binary.BigEndian.Uint32(b[:4]) {
+		return "", errors.New("invalid name")
+	}
+	return string(v), nil
+}

pkg/handler/sni/metadata.go

@@ -0,0 +1,23 @@
+package sni
+
+import (
+	"time"
+
+	md "github.com/go-gost/gost/pkg/metadata"
+)
+
+type metadata struct {
+	readTimeout time.Duration
+	retryCount  int
+}
+
+func (h *sniHandler) parseMetadata(md md.Metadata) (err error) {
+	const (
+		readTimeout = "readTimeout"
+		retryCount  = "retry"
+	)
+
+	h.md.readTimeout = md.GetDuration(readTimeout)
+	h.md.retryCount = md.GetInt(retryCount)
+	return
+}

pkg/listener/tls/listener.go

@@ -5,7 +5,6 @@ import (
 	"net"
 
 	"github.com/go-gost/gost/pkg/common/util"
-	tls_util "github.com/go-gost/gost/pkg/common/util/tls"
 	"github.com/go-gost/gost/pkg/listener"
 	"github.com/go-gost/gost/pkg/logger"
 	md "github.com/go-gost/gost/pkg/metadata"
@@ -55,17 +54,3 @@ func (l *tlsListener) Init(md md.Metadata) (err error) {
 	l.Listener = ln
 	return
 }
-
-func (l *tlsListener) parseMetadata(md md.Metadata) (err error) {
-	l.md.tlsConfig, err = tls_util.LoadTLSConfig(
-		md.GetString(certFile),
-		md.GetString(keyFile),
-		md.GetString(caFile),
-	)
-	if err != nil {
-		return
-	}
-
-	l.md.keepAlivePeriod = md.GetDuration(keepAlivePeriod)
-	return
-}

pkg/listener/tls/metadata.go

@@ -3,16 +3,39 @@ package tls
 import (
 	"crypto/tls"
 	"time"
-)
 
-const (
+	tls_util "github.com/go-gost/gost/pkg/common/util/tls"
-	certFile        = "certFile"
+	md "github.com/go-gost/gost/pkg/metadata"
-	keyFile         = "keyFile"
-	caFile          = "caFile"
-	keepAlivePeriod = "keepAlivePeriod"
 )
 
 type metadata struct {
 	tlsConfig       *tls.Config
 	keepAlivePeriod time.Duration
 }
+
+func (l *tlsListener) parseMetadata(md md.Metadata) (err error) {
+	const (
+		certFile        = "certFile"
+		keyFile         = "keyFile"
+		caFile          = "caFile"
+		keepAlivePeriod = "keepAlivePeriod"
+	)
+
+	if md.GetString(certFile) != "" ||
+		md.GetString(keyFile) != "" ||
+		md.GetString(caFile) != "" {
+		l.md.tlsConfig, err = tls_util.LoadTLSConfig(
+			md.GetString(certFile),
+			md.GetString(keyFile),
+			md.GetString(caFile),
+		)
+		if err != nil {
+			return
+		}
+	} else {
+		l.md.tlsConfig = tls_util.DefaultConfig
+	}
+
+	l.md.keepAlivePeriod = md.GetDuration(keepAlivePeriod)
+	return
+}