Add command line client with SOCKS

cmd/client/socks2ss.go

@@ -0,0 +1,204 @@
+// Copyright 2022 Jigsaw Operations LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main
+
+import (
+ "encoding/base64"
+ "errors"
+ "flag"
+ "fmt"
+ "net"
+ "net/url"
+ "os"
+ "os/signal"
+ "strconv"
+ "strings"
+ "syscall"
+
+ "github.com/Jigsaw-Code/outline-ss-server/client"
+ onet "github.com/Jigsaw-Code/outline-ss-server/net"
+ "github.com/op/go-logging"
+ "github.com/shadowsocks/go-shadowsocks2/socks"
+ "golang.org/x/crypto/ssh/terminal"
+)
+
+var logger *logging.Logger
+
+func init() {
+ var prefix = "%{level:.1s}%{time:2006-01-02T15:04:05.000Z07:00} %{pid} %{shortfile}]"
+ if terminal.IsTerminal(int(os.Stderr.Fd())) {
+ // Add color only if the output is the terminal
+ prefix = strings.Join([]string{"%{color}", prefix, "%{color:reset}"}, "")
+ }
+ logging.SetFormatter(logging.MustStringFormatter(strings.Join([]string{prefix, " %{message}"}, "")))
+ logging.SetBackend(logging.NewLogBackend(os.Stderr, "", 0))
+ logger = logging.MustGetLogger("")
+}
+
+type sessionConfig struct {
+ host string
+ port int
+ cipher string
+ secret string
+}
+
+func parseAccessKey(k string) (sessionConfig, error) {
+ u, err := url.Parse(k)
+ if err != nil {
+ return sessionConfig{}, err
+ }
+
+ port, err := strconv.Atoi(u.Port())
+ if err != nil {
+ return sessionConfig{}, fmt.Errorf("invalid port: %v", err)
+ }
+
+ cipherAndSecret := u.User.String()
+
+ // If we see a ":" in the string, assume its not base64 encoded and skip decoding
+ if !strings.Contains(cipherAndSecret, ":") {
+ // Attempt to decode with padding
+ b, err := base64.StdEncoding.DecodeString(cipherAndSecret)
+ if err != nil {
+ // Attempt to decode without padding
+ b, err = base64.RawStdEncoding.DecodeString(cipherAndSecret)
+ if err != nil {
+ return sessionConfig{}, fmt.Errorf("invalid password in key: %v", err)
+ }
+ }
+ cipherAndSecret = string(b)
+ }
+
+ p := strings.Split(cipherAndSecret, ":")
+ if len(p) != 2 {
+ return sessionConfig{}, fmt.Errorf("invalid password in key")
+ }
+
+ return sessionConfig{
+ host: u.Hostname(),
+ port: port,
+ cipher: p[0],
+ secret: p[1],
+ }, nil
+}
+
+type SocksToSS struct {
+ config sessionConfig
+ listener *net.TCPListener
+}
+
+// RunSocksToSS starts a SOCKS server which proxies connections to the specified shadowsocks server.
+func RunSocksToSS(bindAddr string, listenPort int, config sessionConfig) (*SocksToSS, error) {
+ listener, err := net.ListenTCP("tcp", &net.TCPAddr{IP: net.ParseIP(bindAddr), Port: listenPort})
+ if err != nil {
+ return nil, fmt.Errorf("listenTCP failed: %v", err)
+ }
+ logger.Infof("Listenting at %v", listener.Addr())
+
+ ssClient, err := client.NewClient(config.host, config.port, config.secret, config.cipher)
+ if err != nil {
+ return nil, fmt.Errorf("failed connecting to server: %v", err)
+ }
+
+ go func() {
+ for {
+ clientConn, err := listener.AcceptTCP()
+ if err != nil {
+ if errors.Is(err, net.ErrClosed) {
+ logger.Info("SOCKS listener closed")
+ } else {
+ logger.Errorf("Accepting SOCKS connection failed: %v\n", err)
+ }
+ break
+ }
+ go func() {
+ defer clientConn.Close()
+
+ tgtAddr, err := socks.Handshake(clientConn)
+ if err != nil {
+ logger.Errorf("SOCKS handshake failed: %v", err)
+ return
+ }
+
+ logger.Debugf("Opening connection for %s", tgtAddr)
+ targetConn, err := ssClient.DialTCP(nil, tgtAddr.String())
+ if err != nil {
+ logger.Errorf("Failed to dial: %v", err)
+ return
+ }
+ defer targetConn.Close()
+ _, _, err = onet.Relay(clientConn, targetConn)
+ if err != nil {
+ logger.Errorf("Relay failed: %v", err)
+ return
+ }
+ logger.Debugf("Connection closed %s", tgtAddr)
+ }()
+ }
+ }()
+ return &SocksToSS{listener: listener}, nil
+}
+
+// ListenAddr returns the listening address used by the SOCKS server
+func (s *SocksToSS) ListenAddr() net.Addr {
+ return s.listener.Addr()
+}
+
+// Stop stops the SOCKS server
+func (s *SocksToSS) Stop() error {
+ return s.listener.Close()
+}
+
+func main() {
+ var flags struct {
+ BindAddr string
+ ListenPort int
+ AccessKey string
+ Verbose bool
+ }
+
+ flag.StringVar(&flags.BindAddr, "bind", "127.0.0.1", "Local address to bind to.")
+ flag.IntVar(&flags.ListenPort, "port", 1080, "Local port to listen on.")
+ flag.StringVar(&flags.AccessKey, "key", "", "Access key specifying how to connect to the server. Only ss:// links are accepted.")
+ flag.BoolVar(&flags.Verbose, "verbose", false, "Enables verbose logging output")
+
+ flag.Parse()
+
+ if flags.Verbose {
+ logging.SetLevel(logging.DEBUG, "")
+ } else {
+ logging.SetLevel(logging.INFO, "")
+ }
+
+ if flags.AccessKey == "" {
+ flag.Usage()
+ return
+ }
+
+ sc, err := parseAccessKey(flags.AccessKey)
+ if err != nil {
+ logger.Fatalf("Invalid key: %v", err)
+ }
+
+ // TODO: add UDP support for ScoksToSS
+ _, err = RunSocksToSS(flags.BindAddr, flags.ListenPort, sc)
+ if err != nil {
+ logger.Fatalf("Failed running client: %v", err)
+ }
+
+ sigCh := make(chan os.Signal, 1)
+ signal.Notify(sigCh, syscall.SIGINT, syscall.SIGTERM)
+ <-sigCh
+}